BCH
Professeur
Scientific activity
Researcher profile
Faculty researcher at the University of Yaoundé I. Grade: Professeur.
Scientific publications
Arnaud Fondjo Kouam, Cromwel Tepap Zemnou, Armel Jackson Seukep, Babayemi Olawale Oladejo, Fredy Brice Nemg Simo, Kerinyuy Juliene Kongnyuy and 4 more
Fitoterapia
Arnaud Fondjo Kouam, Saturine Mengwe Mofor, Madeleine Yvanna Nyangono Essam, Armelle Gaelle Kwesseu Fepa, Elisabeth Menkem Zeuko’o, Armel Jackson Seukep and 4 more
PLoS ONE
The prevalence of type 2 Diabetes Mellitus (T2DM) is increasing globally. Besides the traditional complications associated with T2DM, such as diabetic retinopathy, neuropathy, and kidney diseases, new complications including liver diseases, are increasingly being documented. This study aimed to examine serum biomarkers of liver injury and the related risk factors in T2DM patients at the Buea Regional Hospital, Cameroon. The sociodemographic, clinical, and behavioral characteristics of patients with T2DM were captured using a structured questionnaire. Anthropometric parameters were measured, and the Body Mass Index was calculated. Blood samples were analyzed for biomarkers of liver damage (ALT, AST, GGT, and ALP), considering a liver enzyme profile abnormal if it had more than 2 abnormally elevated values. Bivariate and multivariate logistic regressions analysis were used to identify risk factors, with significance set at P < 0.05. Among the 170 participants recruited, 75.9% were female. The median age was 62 years. Over half (52.9%) were married, 64.7% attended primary school and 55.3% were retired. Also, 59.4% had diabetes for over five years and all reported knowledge of diabetes care. About 73.3% adhered to their medication, 64.7% consumed alcohol, 28.8% smoked tobacco, with 22.4% engaged in physical activity and 77.6% with comorbidities. Blood sugar monitoring was practiced by 80%, with 66.5% having high blood pressure. Healthy weight individuals were 31.2% while 41.2% were obese and 56.5% had abnormal liver enzyme profiles. Five factors: duration of illness, physical inactivity, tobacco smoking, comorbidities and overweight/obesity were significantly (P < 0.05) associated with abnormal liver enzyme profile. Our findings identify risk factors linked to elevated liver enzyme markers indicating liver injury in T2DM patients.
Ridel Mbiandou Njami, Ferdinand Kouoh Elombo, Sylvain Nsangou Pechangou, Bradley W. Bolling, Frédéric Nico Njayou, Paul Fewou Moundipa
Journal of Pharmacognosy and Phytochemistry
A concentrated phenolic compounds extract (KPE) from the plant Khaya grandifoliola was assessed in vitro for antioxidant and anti-inflammatory properties and its effect on erythrocytes Plasma Membrane Redox System (PMRS). Phenolic compounds quantity per g of dry matter (DM) were total phenols (57. 93±0.42mg EGA) and flavonoids (2.84±0.04 mg EQ). Antiradicalar half scavenging concentrations were 6.25±0. 07 μg/mL and 11.65±0.92 μg/mL for DPPH° and HO° tests, respectively. Total Antioxidant Capacity was 76.82±0.35 mgEq AA/g DM and half inhibitory concentrations (IC50) of 8.50±0.14 µg/mL, 8.7±0.14 µg/mL and 71.05±1.20 µg/mL found for inhibition of lipids and proteins oxidation and TNFα production in Jurkat T cells, respectively. KPE activated erythrocytes PMRS with an EC50 of 5.90±0.00 µg/mL. Conclusively, KPE may be suggested as potential ingredient of functional foods against health conditions involving oxidative stress and inflammation.
Jacqueline Manjia Njikam, Emmanuel Mfotie Njoya, Anandaram Harishchander, Aristide Mfifen Munvera, Frank Abimbola Ogundolie, Pierre Mkounga and 3 more
Research Square
Fils Armand Ella, Simon Ngamli Fewou, Mario Robillard Didier Koloko, Pascal Owona, Frédéric Nico Njayou, Paul Fewou Moundipa
American Journal of Biomedical and Life Sciences
Alzheimer’s disease (AD) is a multifactorial, progressive neurodegenerative disorder with dementia and persistent impairment of cognitive functions as the main clinical characteristics. Although signs of progress are being made in developing AD therapy, there is no effective drug capable of stopping and/or slowing down the progression of the disease. We have previously indicated in an in vitro setting of AD that <i>Khaya grandifololia</i> (KG) crude extract possesses antioxidant, anti-inflammatory, and neuroprotective activities. In the current work, we have evaluated the activity of KG hydroethanolic (KG-HE) extract in preventing cognitive impairment and promoting memory improvement in vivo. Results from behavioral tests indicated a significant improvement in memory performance and a delay in depression-like behavior upon treatment of rats with KG-HE extract (5, 25, and 50 mg/kg) or donepezil (1 mg/kg) as standard. Because scopolamine (1 mg/kg) impaired cognitive performance in the tail suspension test, Morris Water Maze test, and Novelty Suppressed Feeding Test, KG-HE extract (5, 25, and 50 mg/kg) or donepezil (1 mg/kg) treatment prevented scopolamine-induced performance impairment. Moreover, both KG-HE extract (5, 25, and 50 mg/kg) and donepezil (1 mg/kg) prevented the scopolamine-induced cognitive impairment by inhibiting the acetylcholinesterase activity. In addition, the brain parameters of stress oxidation (SOD, CAT, and GSH) reduced by scopolamine treatment were regulated by the administration of KG-HE extract or the standard drug donepezil. An increase in the MDA level and the phosphatase activity both in the serum and brain due to scopolamine treatment was restored by the administration of KG-HE extract or donepezil. Taken together, these results suggest that KG-HE extract improves cognition and relieves the scopolamine-induced cognitive impairment via activation of the cholinergic and anti-oxidation systems in rats.
Arnauld Efon Ekangouo, Hugues C. Nana-Djeunga, Guilhem Sempéré, Joseph Kamgno, Flobert Njiokou, Paul Fewou Moundipa and 1 more
Pathogens
Vector control using larvicides is the main alternative strategy to address limits of preventive chemotherapy using ivermectin for the control of onchocerciasis. However, it remains substantially limited by implementation difficulties, ecological concerns and the resistance of vector populations. Therefore, efficient and environmentally safe alternative control strategies are still needed. This study explores the composition of the blackfly bacteriome and its variability in the presence of Onchocerca volvulus infection, in order to determine their potential as a novel vector control-based approach to fight onchocerciasis. An entomological survey of a collection of samples was performed in the Bafia health district, a historical endemic focus for onchocerciasis in Cameroon. A total of 1270 blackflies were dissected and the infection rate was 10.1%, indicative of ongoing transmission of onchocerciasis in the surveyed communities. Sequencing process of blackflies’ gut DNA for bacteria screening revealed 14 phyla and 123 genera, highlighting the diversity of gut blackflies bacterial communities. Eight bacteria formed the core of blackfly bacteriome and Wolbachia was the predominant genus with 73.4% of relative abundance of blackflies’ gut bacterial communities. Acidomonas and Roseanomas genera were significantly abundant among infected blackflies (p = 0.01), whereas other genera such as Brevibacterium and Fructobacillus were associated with the absence of infection (p = 0.0009). Differences in gut bacterial distribution of blackflies according to their infection status by the parasite suggest a causal relationship between the bacteriome composition and the onset of blackflies’ infection by O. volvulus or vice versa. Blackfly native bacteria are then potentially involved in infection by O. volvulus, either by facilitating or preventing the parasite infestation of the vector. These bacteria represent an interesting potential as a biological tool/target for a novel approach of vector control to fight onchocerciasis.
Pascal Dieudonné Djamen Chuisseu, Boris R.G. Tietcheu, Nelly C.K. Younang, Arnaud Fondjo Kouam, Brice Fredy Nemg Simo, Angèle N. Tchana and 5 more
Investigational Medicinal Chemistry and Pharmacology
Background: Desmodium adscendens (DA) is an herbaceous plant found in Africa and South America and used in traditional medicine against liver-related diseases. In the present study, the aqueous decoctions from DA were tested for its antioxidant and hepato-(protective and curative) properties on CCl4-induced acute injury on primary culture rats’ hepatocytes. We also investigated its […]
Wilfred A. Abia, Angèle N. Tchana, Doumani Djonabaye, Bojan Šarkanj, Euloge Yiagnigni Mfopou, Chibundu N. Ezekiel and 6 more
Abstract Background In Cameroon dietary staples are contaminated with diverse toxic fungal metabolites, known as mycotoxins. Aflatoxins and fumonisins are of particular public health concern, particularly in relation to cancer and/or early life stunting. Mixtures of these toxins are predicted from food measures, and in this work, the levels and frequencies of urinary mycotoxin biomarkers are reported in Cameroonian adults. Methods A single first void urine sample was collected from 89 adults (aged range: 28–85, male 39, female 50) from the city of Yaoundé, Centre Region, Cameroon. Urines were tested for eight distinct mycotoxins using measures of both parent compounds and/or their metabolites by Liquid Chromatography tandem mass spectrometry (LC-MS/MS). Results Altogether seven distinct mycotoxins, aflatoxin, fumonisin, deoxynivalenol, zearalenone, nivalenol, ochratoxin A and citrinin, (or their metabolites) were observed in urine samples. At least one mycotoxin was detected in all of the urine samples, 87 (97.8%) of which were above the method’s quantification limit. Aflatoxin M 1 was detected in 42% (n.d. − 0.21 µg L − 1 ) of samples of which about a quarter additionally contained fumonisin B 1 . Of the remaining toxins deoxynivalenol, zearalenone, ochratoxin A, nivalenol and citrinin were present in 78%, 99% 95%, 53%, and 87% of the samples respectively. Alternariol was not detected in any sample. Mixtures of mycotoxins in the samples were frequently observed with 64 samples (72%) containing more than five mycotoxins. Estimates of intake exceeded the TDIs for fumonisin (n = 4), deoxynivalenol (n = 1) and zearalenone (n = 2), no TDI is set for aflatoxin. Conclusions This study reveals frequent co-exposure of Cameroonian individuals to a complex mixture of toxic and carcinogenic mycotoxins, with mixtures of aflatoxin and fumonisin a particular priority from a public health standpoint.
Viviane L. Ndam Ngoungoure, Emmanuel Mfotie Njoya, Simon Ngamli Fewou, Armand Fils Ella, Lyndy J. McGaw, Paul Fewou Moundipa
Investigational Medicinal Chemistry and Pharmacology
Background: Besides the principal hallmark of Alzheimer’s disease (AD) and Parkinson’s disease (PD) which is accumulation of mis-folding protein in the brain; cholinergic deficit, neuro-inflammation and oxidative stress are also implicated the pathogenesis of the above-mentioned diseases. In the present study, different plant parts were collected in an ethnopharmacological survey carried out in the […]
Faustin Pascal Tsagué Manfo, C. Harthé, Edouard Akono Nantia, H. Déchaud, Angèle N. Tchana, Marie-Tthérèse Zabot and 2 more
Toxicology and Industrial Health
The consequences of bisphenol A (BPA) exposure on male reproductive function were studied in two populations from Cameroon, farmers using agro pesticides in Djutitsa (rural area) and townsmen in Yaoundé (urban area, Centre region). Urinary BPA concentration from all participants was measured, and the values were correlated with biochemical markers of male reproductive function. The data showed that BPA could be detected in 92.6% of urine participants, with an average concentration of 2.18 ± 1.97 µg/g creatinine but with no significant difference between the urinary BPA concentration from rural and urban populations. From BPA urinary concentration, the BPA average daily intake was estimated to be 0.06 ± 0.05 μg/kg/day (3.51 µg/day per individual) in the Cameroon population. Interestingly, free and bioavailable testosterone concentrations and estradiol/testosterone ratio correlated with BPA levels in the overall population. When data were analysed according to residence, BPA correlated with total testosterone levels ( r = -0.433) and estradiol/testosterone ratio ( r = 0.338) in the urban residents only, while the rural population exhibited significant increases in sex-hormone-binding globulin with increased BPA exposure. Our data showed that the male Cameroon population is exposed to BPA but that inconstant BPA association to endocrine reproductive markers suggests that other environmental factors in combination with BPA exposure might influence testicular function.
Emmanuel Mfotie Njoya, Melanie F. G. Kamini, Wilfred A. Abia, Sylvain Nsangou Pechangou, Frderic Njayou, Angle Tchana and 1 more
Journal of Complementary Medicine Research
Background/Aim: The decoction of Codiaeum variegatum leaves is used by Cameroonian local population in the treatment of amoebic dysentery. The present study was carried out to investigate the safety of the aqueous extract of Codiaeum variegatum leaves on mice and rats of both sexes. Methods: For the acute toxicity study, seven groups of 8 Wistar mice (4 males and 4 females) received orally once distilled water (10 mL.Kg-1) and the aqueous extract in a single dose of 2, 4, 8, 12, 16, and 24 g.Kg-1. These mice were observed for mortality after 48 hours and thereafter for clinical signs daily for 14 days. In the subchronic toxicity evaluation, four groups of 12 Wistar rats (6 males and 6 females) received distilled water (10 mL.Kg-1) and the aqueous extract at doses of 50, 100, and 200 mg.Kg-1 by oral gavage for 28 consecutive days. The body weight was evaluated every 2 days for each animal and after sacrifice, the relative weight of vital organs was determined. Blood serum was used for the analysis of biochemical markers of renal and hepatic toxicity. Results: The administration of the aqueous extract in both acute and subchronic toxicity evaluation did not cause neither significant visible signs of toxicity nor mortality and no significant changes were observed on body weight, relative organ weight and biochemical parameters in treated groups compared to the control groups respectively. Conclusion: These results demonstrated that the aqueous extract of Codiaeum variegatum leaves is non-toxic and may be safely used for its therapeutic application.
Marie Amougou Atsama, Paul Jean Adrien Atangana, Dominique Noah Noah, Paul Fewou Moundipa, Pascal Pineau, Richard Njouom
International Journal of Infectious Diseases
OBJECTIVES: To determine the seroprevalence of hepatitis E virus (HEV) infection in patients with chronic hepatitis and/or hepatocellular carcinoma (HCC) and to assess its potential consequences for disease progression. METHODS: We conducted a prospective case-control study on patients with HCC hepatitis B or C related and non-HCC patients including patients with CLD and patients without clinical evidence of liver disease. Anti-HEV IgG and IgM were tested by ELISA using commercially available kits. Liver damage was assessed by alanine aminotransferase, aspartate aminotransferase, platelets and prothrombin measurements. RESULTS: We observed a significant anti-HEV IgG carriage in HCC patients compared to non-HCC subjects with CLD (41.8% vs 12.6%; P=9.1 E-6; OR=4.8, 95%CI: 2.3-10.6). HCC patients with HEV infection display more profound alterations of circulating liver enzymes, platelets count and prothrombin time than HCC patients without sero-reactivity to HEV. CONCLUSION: Overall, this study indicates a high prevalence of HEV infection in Cameroonian patients with CLD and HCC. These data suggest either that patients with liver tumors are more susceptible to hepeviral infection or that, in a tropical context, HEV might promote the progression of liver diseases towards tumor.
Marie Atsama Amougou, Dominique Noah Noah, Paul Fewou Moundipa, Pascal Pineau, Richard Njouom
BMC Infectious Diseases
BACKGROUND: Hepatocellular Carcinoma (HCC) is one of the commonest cancers in Central Africa, a region with the unusual peculiarity to be hyperendemic for infections with Hepatitis B, C and D viruses. However, data estimating the respective proportions of HCC cases attributable to these viruses are still limited in this area. The current study was undertaken to determine the role of these viruses in HCC compared to non-HCC Cameroonian patients. METHODS: A case-control study was conducted in the Gastroenterology Unit of Central Hospital of Yaounde in collaboration with Centre Pasteur of Cameroon. Blood samples of all HCC cases (n = 88) and matched control individuals without known liver disease (n = 85) were tested for serological markers of Hepatitis B, C and D viral infections using commercially available enzyme immune-assay kits. Hepatitis B and C viral loads were quantified for positive patients by real-time PCR using commercial kits. RESULTS: ). The risk factors analysis showed that both HBV and HCV infections were strongly associated with HCC development in Cameroon with crude odds ratios of 15.98 (95 % CI 6.19-41.25) and 7.33 (95 % CI 2.09-25.77), respectively. Furthermore, the risk of developing HCC increased even more significantly in case of HBV and HDV co-infections with the odd ratio of 29.3 (95 % CI, 4.1-1231). HBV-DNA level was significantly higher in HBsAg-positive HCC-patients than in HBsAg-positive controls with (6.3 Log IU/mL and 5.7 Log IU/mL) respectively (P < 0.05). CONCLUSION: HBV and HCV infections are the mains factors of HCC development in Cameroon. Our results show that patients co-infected with HDV are at very high risk to develop HCC. An active surveillance program of patients and, foremost, an easier access to antivirals and primary prevention measures are crucial steps to reduce the incidence of HCC in this country. Due to the lack of truly efficient antiviral therapy, the fate of HDV-infected patients remains, however, particularly worrying.
Wilfred A. Abiaa, Chibundu N. Ezekiel, Benedikt Warth, Michael Sulyok, Paul C. Turner, Rudolf Krska and 1 more
World Academy of Science, Engineering and Technology, International Journal of Medical and Health Sciences
Frédéric Nico Njayou, A. Amougou, Romeo Fouemene Tsayem, Jacqueline Njikam Manjia, Swetha Rudraiah, Bradley W. Bolling and 2 more
Cell Stress and Chaperones
The in vitro antioxidant properties, cytoprotective activity, and ability to induce nuclear translocation of nuclear factor E2-related factor-2 (Nrf-2) of five solvent fractions of the methylene chloride/methanol (1:1 v/v) extract of Khaya grandifoliola (Meliaceae) and Entada africana (Fabaceae) were evaluated. Five antioxidant endpoints were used in the antioxidant activity investigation. The total phenolic content of the fractions was assessed as to the Folin-Ciocalteu method and the profile of interesting fractions analyzed by high-performance liquid chromatography (HPLC). The cytoprotective activity of fractions was determined by H2O2-induced oxidative stress in HC-04 cells by measuring lactate dehydrogenase (LDH) leakage into culture medium. HC-04 cells were used to investigate the ability to induce nuclear translocation of Nrf2. For both plants, the methylene chloride/methanol (90/10; v/v) fraction (F10), methylene chloride/methanol (75/25; v/v) (F25), and the methanolic fraction (F100) were found to have the highest total polyphenol content and exhibited high antioxidant activity strongly correlated with total polyphenol content. The cytoprotective activity of fraction F25 from both plants was comparable to that of quercetin (3.40 ± 0.05 μg/mL), inhibiting LDH leakage with a low half inhibition concentration (IC50) of 4.05 ± 0.03 and 3.8 ± 0.02 μg/mL for K. grandifoliola and E. africana, respectively. Lastly, fraction F25 of K. grandifoliola significantly (P < 0.05) induced nuclear Nrf2 translocation by sixfold, whereas that from E. africana and quercetin was only twofold. The results indicate for the first time that fraction F25 of the studied plants is more antioxidant and cytoprotective and induces nuclear translocation of Nrf2 in a human hepatocyte cell line.
Borris Rosnay Galani Tietcheu, Gabriele Sass, Nico Fréderic Njayou, Pierre Mkounga, Gisa Tiegs, Paul Fewou Moundipa
The American Journal of Chinese Medicine
Entada africana (Ea) is a medicinal plant from the family of Fabaceae, used in Western and Central Africa regions to treat liver diseases. Antiviral properties of this plant were reported against Hepatitis B virus, while effects against Hepatitis C virus (HCV) remained unknown. This study reports for the first time, the effects of Ea crude extract and fractions on HCV replication. Furthermore, the effect of one Ea fraction on the transcriptional expression of two interferon-stimulated genes (ISGs) was also investigated. A methylene chloride-methanol (MCM) stem bark crude extract and different MCM fractions (EaF0, EaF5, EaF10, EaF25, and EaF100) were prepared and tested on LucUbiNeo-ET and Huh 5.15 cells lines used as genotype 1b (GT1b) replicon systems. The cells were incubated with crude extract and fractions at various concentrations. Then, the antiviral activity was assessed by luciferase reporter assay and the cell viability by MTT assay. Gene expression was also analyzed using quantitative real time RT-PCR. Results showed that the Ea crude extract dose-dependently inhibited HCV replication after 24 and 72 h of incubation. The MCM fraction (EaF10) exhibited the strongest anti-HCV properties with an IC50 = 0.453 ± 0.00117 mg/ml and no reduction of cell viability at antiviral concentrations. This fraction also significantly induced the expression of heme oxygenase-1 (HO-1) (5.36-fold), and 2'-5' oligoadenylate synthetase-3 (OAS-3) by 4.46-fold after 6 h and 2.31-fold after 24 h at the mRNA levels. Taken altogether, these results suggest that Ea may contain ingredients that indirectly regulate HCV replication.
Brice Ayissi Owona, Nico Fréderic Njayou, Stefan Laufer, Paul Fewou Moundipa, Hermann J. Schluesener
Journal of Ethnopharmacology
Faustin Pascal Tsagué Manfo, R. Jubendradass, Edouard Akono Nantia, Paul Fewou Moundipa, Premendu P. Mathur
Reviews of Environmental Contamination and Toxicology
Wilfred A. Abia, Benedikt Warth, Michael Sulyok, Rudolf Krska, Angèle N. Tchana, Patrick Berka Njobeh and 2 more
Food Control
Landry Lienou Lienou, Bruno Phélix Telefo, Balé Bayala, Didiane Mefokou Yemele, Richard Simo Tagne, Stephanie Chekem Goka and 3 more
BMC Complementary and Alternative Medicine
BACKGROUND: Senecio biafrae (Asteraceae) is a medicinal plant widely used by traditional healers in the western region of Cameroon for the treatment of female infertility. This experiment was designed to evaluate the effect of the aqueous extract from leaves and stems of S. biafrae (AESb) on the onset of puberty and some biochemical and physiological parameters of reproduction in immature Wistar female rats. METHODS: Different doses of AESb were daily and orally administered to immature female rats (13 animals/group) for 30 days. At the end of the treatment period, six animal of each experimental group were sacrificed and their body, ovarian, uterus weight; uterine, ovarian protein or cholesterol level as well as data on puberty onset recorded. The remaining animals of each group were used for the fertility test and some gestational parameters recorded. RESULTS: A linear increase in the growth rate of all animals was observed. The body weight gain in animals treated at the dose of 8 mg/kg of AESb significantly increased (p < 0.05) after 25 days of treatment while those receiving the doses of 32 and 64 mg/kg presented a significantly low body weight gain starting from the 19th day till the end of the treatment period. The ages (days) of animals at vaginal opening (VO) was significantly reduced (p < 0.05) in those treated with the doses of 32 (41.25 ± 0.51) and 64 mg/kg (41.42 ± 0.54) as compared to control animals (43.33 ± 0.73). AESb significantly increased (p < 0.05) the ovarian weight and the number of corpora lutea in animals treated with 8 mg/kg as well as the uterine weight and protein levels irrespective of the dose. No significant effect of the extract on various fertility and gestational parameters was registered. CONCLUSION: The overall results of the present study provide evidence on the puberty onset induction and ovarian folliculogenesis effect of AESb in immature female rat.
Edouard Akono Nantia, P. F. T. Manfo, Nathalie Beboy, Carine Travert, Serge Carreau, Thomas K. Monsees and 1 more
Andrologia
We evaluated the effect of the methanol extract of Basella alba (MEBa) on testosterone level and fecundity/fertility in male rats exposed in utero to flutamide - an androgen receptor antagonist. For this purpose, 1.5- and 2.5 -month-old male rats exposed in utero to flutamide were treated with the MEBa (1 mg kg(-1) ) for 2 and 1 month respectively. Five days before the end of treatment, rats were housed with females to assess their fecundity/fertility. Thereafter, rats were sacrificed and blood collected for the quantification of testosterone. Flutamide-exposed male rats showed a decrease in their ano-genital distance (AGD, P < 0.05) and were infertile. In normal (methylcellulose-exposed) animals, MEBa provoked an increase in testosterone level in 1.5- (P < 0.008) and 2.5 -month-old rats (P < 0.01) concomitantly with the improvement in their fecundity by 25%. In flutamide-exposed male rats, MEBa increased testosterone level in 1.5 -month-old rats (P < 0.001) without any effect on their fecundity; while in 2.5- month-old rats, MEBa did not affect the testosterone level but improved fecundity (by 25%) and fertility (P < 0.001). This study demonstrated the positive effect of MEBa to enhance fecundity/fertility in normal male rats and in rats exposed to the antiandrogen flutamide during their foetal life.
Angèle N. Tchana, Paul Fewou Moundipa, Félicité Mbiapo Tchouanguep
International Journal of Environmental Research and Public Health
Aflatoxins are food contaminants usually associated with hepatitis, immunodepression, impairment of fertility and cancer. The present work was to determine the presence of aflatoxins in eggs, milk, urine, and blood samples that were collected from various sources and periods; and hepatitis B virus antigen in blood samples. Aflatoxin was found in eggs (45.2%), cow raw milk (15.9%), breast milk (4.8%), urine from kwashiorkor and marasmic kwashiorkor children (45.5%), and sera from primary liver cancer patients (63.9%); HbsAg was also detected in 69.4% of the serum samples, but there was no association between both factors. Both AF and hepatitis B virus seem to be risk factors that could increase the incidence and prevalence rates of malnutrition and cancer in Cameroon.
Guy R. Njitchouang, Flobert Njiokou, H. C. Nana Djeunga, Paul Fewou Moundipa, T Asonganyi, G Cuny and 1 more
Journal of Cell and Animal Biology
To better understand the epidemiology of sleeping sickness in two Human African Trypanosomiasis (HAT) sub foci (central and northern sub foci) of the Fontem focus where diversity in the prevalence of Trypanosoma bucei. gambiense was reported in domestic animals and man, 397 domestic animals were sampled in eight villages. Parasitological tests revealed trypanosomes in 86 (21.60%) animals. The CATT test was positive in 254 (64%) animals with the lowest value in dogs. The PCR test revealed T. b. gambiense in 11.55% of pigs, 3.45% of goats and 15.38% of sheep. The T. b. gambiense infection rates were not significantly different between the two sub foci. However, T. b. gambiense was found in animals from all villages of the Northern sub focus while only animals from Menji and Nsoko (Central sub focus) revealed this infection. The detection of T. b. gambiense in animals of the central sub focus was in line with results of medical surveys where HAT patients were detected in the same villages. The absence of patients in the northern sub focus despite the circulation of T. b. gambiense in animals from all villages of this sub focus since several years is surprising and needed more investigations. Key words: Domestic animals, T. b. gambiense, sleeping sickness, animal reservoir
Paul Fewou Moundipa, Thomas K. Monsees, Nathalie Sara E. Beboy, Serge Carreau, Edouard Akono Nantia
African Journal of Traditional Complementary and Alternative Medicines
Hibiscus macranthus and Basella alba leaves are mixed in a remedy given, in western Cameroon, to the new king for some weeks during initiation period to sustain his sexual performance. This plant extracts enhanced blood testosterone level in male rats. They were further studied for androgenic activity since they could be used to alleviate male infertility or to treat androgen deficiency in ageing male. Using rat testis slices, methanol extract of both plants significantly induced testosterone synthesis. In primary Leydig cell cultures of bull and rat, extracts from B. alba significantly enhanced testosterone levels in a dose dependant manner. H. macranthus showed no androgenic activity. Phytochemical screening and HPLC study of B. alba extracts revealed presence of terpenoids, limonoides and coumarins. This extract also modulated aromatase gene activity in Leydig cell cultures. In vivo, methanol extract (1 mg/kg) given to adult male rats significantly increased serum testosterone level after 30 days (p<0.0005). This dose was found to be efficient whereas higher dosages of extract were ineffective. No sign of toxicity was detected in liver and kidney during acute or chronic studies. Acknowledgment: IFS, AUF, Universities of Giessen and Caen (FRG, France)
Gilbert Deccaux Wabo Fotso Kapche, Christian D. Fozing, Jean Hubert Donfack, Ghislain W. Fotso, Amadou Dawé, Angèle N. Tchana and 4 more
ChemInform
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Jean Hubert Donfack, Frederic Njayou Nico, Barthélémy Ngameni, Angèle N. Tchana, Paola Vita Finzi, Bonaventure T. Ngadjui and 1 more
亚洲传统医药
Summary The 40% hydroethanolic stem bark extract (HE40) from Erythrina senegalensis was subjected to purification by repeated column chromatographies. Three diprenylated isoflavonoids were isolated and identified as 2,3-dihydro-2’-hydroxyosajin (1), osajin (2) and 6,8-diprenylgenistein (3). These compounds were tested for hepatoprotective activities against in vitro CCl4-induced hepatitis in rat liver slices. The following four model systems were used to measure the antioxidant activity of these three isoflavones: 2,4-dinitrophenyl-1-picrylhydrazyl (DPPH) radical scavenging activities, sCarotene-Linoleic Acid Model System (s-CLAMS), Ferric-Reducing Antioxidant Power (FRAP) assay and microsomal lipid peroxidation. The obtained hepatoprotective percentages of compounds (1) (2) (3) were respectively 71.8±1.45, 67.54±3.56 and 69.41±2.56. By comparison to compound (2) and (3), compound (1) showed significant antioxidant effect with EC50 values of 41.28±1.2, 31.27± 2.14, 19.17±1.2 and 15.99±0.49 µg/ml respectively for the radical-scavenging action, inhibition of microsomal lipid peroxidation, s-CLAMS and FRAP assays. The hepatoprotective activity of silymarin used as reference compound was lower than the activities of isolated compounds. The results obtained provide promising baseline information for the potential use of this crude extract as well as some of the isolated compounds for their hepatoprotective and antioxidant activities. It is also worth noting that these results validate, by in vitro tests, the therapeutic use of the plant in traditional medicine.
Edouard Akono Nantia, Paul Fewou Moundipa, Nathalie Sara E. Beboy, Thomas K. Monsees, Serge Carreau
Andrologie
Phélix Bruno Téléfo, Maria-Teresa Pellicer-Rubio, Paul Fewou Moundipa, Félicité Mbiapo Tchouanguep, Benoît Malpaux, C Tchouanguep
HAL (Le Centre pour la Communication Scientifique Directe)
International audience
Paul Fewou Moundipa, Silvère Augustin Ngouela, Georges Alain Tchamba, Nico Fréderic Njayou, Pascal Dieudonné Djamen Chuisseu, Fabien Zelefack and 1 more
International Journal of Pharmacology
Paul Fewou Moundipa, Silvère Ngouela, Pièrre Kamtchouing, Etienne Tsamo, Félicité Mbiapo Tchouanguep, Serge Carreau
Asian Journal of Andrology
AIM: To find an in vitro system for the measurement of the androgenic effects of different extracts of Hibiscus macranthus (Malvaceae) and Basella alba (Basellaceae). METHODS: The production of testosterone from testes slices incubated in two media, either Krebs-Henseleit buffer containing 0.5% Bovine serum albumin (BSA) or Dubecco's Modified Eagle's medium-F12 Ham nutrient mixture (DME/Ham F12), under a mixture of 5% CO2 in 95% air was determined either in the presence or absence of cofactors and Hibiscus macranthus plus Basella alba (HMBA) extracts. RESULTS: The testosterone production was increased in testes slices incubated in DME/Ham F12 medium in response to the cofactors (49%) and aqueous extracts (34%-60% according to dilutions). Under the same atmospheric conditions, there was no positive response of the testes slices to either cofactor or HMBA extract stimulation in Krebs-Henseleit buffer containing 0.5% BSA. In further investigations related to the effect of HMBA, the DME/Ham F12 medium was used. The results obtained from the in vitro test showed that the activity was present mainly in methylene chloride and methanol, since these extracts induced an increase in testosterone production by testes slices. CONCLUSION: The testes slice system is suitable to be used for further in vitro investigations of the isolation of androgenic bioactive components of plants.
Paul Fewou Moundipa, Kamini G. Melanie Flore, Charles Félix Bilong Bilong, Iris Bruchhaus
African Journal of Traditional Complementary and Alternative Medicines
Fifty five medicinal plants belonging to different families selected on the basis of their traditional use against jaundice and various liver disorders were tested for their amoebicidal activities. They were extracted and tested for their antiamoebic activity in vitro using polyxenic culture of Entamoebic histolytica. As the result, 14 exhibited an antiamoebic activity at a dose of 100μg/ml from the second to the fourth day of incubation. The 14 extracts selected extracts were additionnaly tested for 6 days at 10, 100 and 500μg/ml of concentration, and only the leaves extract of Codiaeum variegatum exhibited a clear antiamoebic activity (EC50=10,74 the second day), and had a more pronounced activity than metronidazole the reference product. Key Words: Medicinal plants; Codiaeum variegatum; In vitro; amoebicidal; Bamun;.Cameroon Afr. J. Trad. CAM (2005) 2 (2): 113-121
Paul Fewou Moundipa, Nathalie Sara E. Beboy, Fabien Zelefack, Silvére Ngouela, Etienne Tsamo, Wolf‐Bernhard Schill and 1 more
Asian Journal of Andrology
AIM: To determine the androgenic effects of Basella alba and Hibiscus macranthus extracts in the rat and the bull, and to develop a novel in vitro test system using Leydig cells from bull testes. METHODS: The effect of methanol extracts from both plants on testosterone production in isolated Leydig cells from the rat and the bull was analyzed using 125I-radioimmunoassay (125I-RIA). Rat Leydig cells were obtained by common methods, whereas a novel technique was used to purify Leydig cells from bull testes. RESULTS: Bull testes from the slaughter house were a cheap source of pure Leydig cells. In culture, these cells produced testosterone for 5-6 days, which can be stimulated by human chorionic gonadotrophin (hCG). Basella alba extracts significantly enhanced testosterone production in bull and rat Leydig cells in a concentration-dependent manner. Hibiscus macranthus showed no androgenic effect but was shown to inhibit testosterone production at higher concentrations. CONCLUSION: Leydig cells purified from bull testes can be used as an alternative tool in experimental animal research. Certain fractions of Basella alba extract demonstrated androgenic potential whereas Hibiscus macranthus extracts did not.
Pierre Watcho, Pièrre Kamtchouing, Sélestin Dongmo Sokeng, Paul Fewou Moundipa, Justine K. Tantchou, J. L. Essame and 1 more
PubMed
AIM: To determine the effect of the aqueous extract of Mondia whitei (Periplocaceae) roots on testosterone production and fertility of male rats. METHODS: Adult male Wistar rats were used. In the acute study, 20 rats were randomly divided into 5 groups of 4 animals each. Four treated groups were administered orally a single dose of Mondia whitei (400 mg/kg) and the controls received a similar amount of distilled water. One group of animals were sacrificed by cervical dislocation 1, 2, 4 and 6 h after treatment, respectively. The controls were sacrificed at 6 h. Testicular testosterone was determined by radioimmunoassay. In the chronic study, 28 rats were divided at random into 4 groups of 7 animals each: Groups 1, 2 and 3 were given orally the plant extract (400 mg.kg(-1).day(-1)) for 2, 4 and 8 days, respectively. The animals of Groups 1 and 2 were sacrificed 24 hours after the last dosing. The controls (Group 4) received the same amount of distilled water for 8 days. The fertility was assessed only in Groups 3 and 4 and after that, the animals were sacrificed and the epididymal sperm density, the serum testosterone and the testicular testosterone and 17 beta-estradiol were assayed. The serum, testicular and epidydimal protein contents were also determined. RESULTS: In the acute treatment groups, the serum and testicular concentrations of testosterone remained unchanged at all the time points. Chronic treatment for 8 days induced a significant increase in the testicular weight, the serum and testicular testosterone, the testicular protein content and the sperm density (P < 0.05-0.01), but did not affect the accessory gland weights, the serum protein contents, the testicular concentration of 17beta -estradiol and the fertility compared to the controls. CONCLUSION: Mondia whitei root extract possesses an androgenic property.
Phélix Bruno Téléfo, Paul Fewou Moundipa, Félicité Mbiapo Tchouanguep
Fitoterapia
Pierre Watcho, Pièrre Kamtchouing, Sélestin Dongmo Sokeng, Paul Fewou Moundipa, Justine K. Tantchou, J. L. Essame and 1 more
Phytotherapy Research
Chronic administration of Mondia whitei L. root bark extract (400 mg/kg/day) for 55 days caused testicular lesions resulting in the cessation of spermatogenesis, degenerative changes in the seminiferous tubules and epididymides. The wet weight of the seminal vesicle increased, whereas the weights of testes, epididymides and ventral prostate were unchanged. The treatment also resulted in a partial antifertility effect, and an increase in the protein content of the testes and epididymides. The cholesterol contents of the testes were significantly elevated after 55 days, whereas testosterone and 17beta-oestradiol contents of the testes were unchanged. Serum protein was elevated but serum testosterone was unchanged. A recovery period resulted in normal spermatogenesis and fertility, suggesting reversible antispermatogenic and antifertility effects of the plant.
Clergé Tchiégang, Paul Fewou Moundipa, Virginie Kapchie Noutchougoue
Journal of Food Engineering
Phélix Bruno Téléfo, Paul Fewou Moundipa, Angèle N. Tchana, C Tchouanguep Dzickotze, Félicité Tchouanguep Mbiapo
Journal of Ethnopharmacology
Pièrre Kamtchouing, Sélestin Dongmo Sokeng, Paul Fewou Moundipa, Pierre Watcho, Hermine Boukeng Jatsa, D. Lontsi
Journal of Ethnopharmacology
Félicité Tchouanguep Mbiapo, Paul Fewou Moundipa
Nutrition Research
Felicite Mbiapo Anqele Tchana, Paul Fewou Moundipa
The Indian Journal of Nutrition and Dietetics
Aflatoxin M 1 (AFM) is one of of many animals biotransformation products of aflatoxin B 1 (AFB); The role of AFB 1 as well as that of AFM 1 as a potent hepatotoxic agent and hepatocarcinogen have been demonstrated. Ruminates and other iactating animals have been shown to secrete AFM 1 in milk after been fed AFB 1 -Contaminated feed. About 1 to 3 per cent of AFB 1 is recovered in the milk as AFM. AFM 1 distribution in dairy products seems to be due to its strong binding to the casein fraction of milk.
Paul Fewou Moundipa, F. Domngang
British Journal Of Nutrition
Wistar albino female rats were maintained for 10 d on diets containing various levels of the vegetable Solanum nigrum. Simultaneously, they received daily intraperitoneal injections of aflatoxin B1 (AFB1) (either 0.2 or 0.4 mg/kg body-weight) diluted in propylene glycol. At the end of the experiment, all animals were killed and their serum and hepatic microsomes were prepared for assay of enzymes. Results showed that aminopyrine N-demethylase activity increased 2.5-fold with 200 (S200) and 600 (S600) g S. nigrum/kg diets. Activity of uridine diphosphate glucuronyltransferase (UDPGT) (EC 2.4.1.17) also increased twofold. Similar results were obtained with glutathione S-transferase (EC 2.5.1.18) activity which increased by 60% with diet S600. After AFB1 treatment, a general increase in the activities of the above enzymes was found, except for UDPGT in the group fed on diet S600. When rats were fed on the diet without S. nigrum, AFB1 induced an increase in alkaline phosphatase (ALP) (EC 3.1.3.1), aspartate aminotransferase (AST) (EC 2.6.1.1) and gamma-glutamyltransferase (gamma-GT) (EC 2.3.2.2) levels in the serum. AFB1 also induced increases in serum ALP and gamma-GT levels when rats were fed on diet S600.
Arnaud Fondjo Kouam, Saturine Mengwe Mofor, Madeleine Yvanna Nyangono Essam, Armelle Gaelle Kwesseu Fepa, Elisabeth Zeuko’o Menkem, Armel Jackson Seukep and 4 more
Research Square
Jr Nyambi Nkiackmenyi Ramin, Arnaud Fondjo Kouam, Elisabeth Zeuko’o Menkem, Armel Jackson Seukep, Armelle Gaelle Kwesseu Fepa, Fils Armand Ella and 4 more
medRxiv
Abstract Cigarette smoking in developing countries like Cameroon is increasing with unspecified exposure levels to cadmium, a known toxic chemical. This study conducted in Buea (Southwest Region, Cameroon) aimed to estimate the risk exposure to cadmium inhalation from smoking and its association with the abnormal level of liver and kidney function biomarkers in apparently healthy smokers. A survey recruited smokers to collect data on smoking habits. Cadmium contents in the major cigarette brands selected served to estimate the cadmium Daily Exposure (DE), Weekly Inhalational Exposure (WIE) and the percentage contribution to the Tolerable Weekly Intake (TWI) of cadmium. Serum alanine aminotransferase (ALT) activity, urea, creatinine contents, and urinary albuminuria and glucosuria were measured in blood and urine samples from active and nonsmokers. The 102 smokers enrolled were categorized respectively as light (37.3%; 38/102), moderate (38.2%; 39/102), and heavy (24.5%; 25/102) smokers, smoking an average number of 4.7 ± 0.5, 9.1 ± 1.5, and 19.1 ± 3.0 cigarettes/day, respectively. Cadmium levels in cigarette brands ranged from 0.72-1.08 µg Cd per gram of tobacco removed from the cigarette. Heavy smokers exceeded the permitted cadmium No Significant Risk Level (NSRL) by up to 28-fold, contributing 4-8% to the cadmium TWI. Serum ALT activity and creatinine content were significantly higher ( P <0.05) in smokers groups compared to non-smokers. Also, moderate and heavy smokers were at a significantly higher risk (relative risk 6.90–13.32; P <0.05) of displaying abnormal elevated serum urea content, positive albuminuria and glucosuria. Our findings demonstrated that healthy active smokers are highly exposed to cadmium inhalation and are at higher risk of displaying abnormally increased levels of biochemical markers of liver and kidney functions, indicating risks of organ damage.
Brice Ayissi Owona, Viviane Ndam Ngoungoure, Jordas Tchana Tchamba, Frédéric Nico Njayou, Paul Fewou Moundipa
Metabolic Brain Disease
Arnaud Fondjo Kouam, Philipe Herman Nfombouot Njitoyap, Fredy Brice Nemg Simo, Tepap Cromwell Zemnou, Kerinyuy Juliene Kongnyuy, Elisabeth Menkem Zeuko’o and 2 more
SSRN Electronic Journal
Arnaud Fondjo Kouam, Cromwel Tepap Zemnou, Eléonore Ngounou, Felicité Syntia Douanla Somene, Elisabeth Zeuko’o Menkem, Amih Elvis Ofon and 2 more
Journal of Ethnopharmacology
Arnaud Fondjo Kouam, Tepap Cromwell Zemnou, Eléonore Ngounou, Felicité Syntia Douanla Somene, Elisabeth Menkem Zeuko’o, Amih Elvis Ofon and 2 more
SSRN Electronic Journal
Wilfred A. Abia, Brandy Perkwang Taty, Kellybright Enih Fokwen, Eucharia A. Abia, Angèle N. Tchana, Paul Fewou Moundipa
Archiv für Lebensmittelhygiene
Foods are frequently contaminated by natural toxins or toxic substances that have been illegally added, some of which are carcinogenic and pose potential cancer risks to consumers, particularly in low- and middle-income countries. This scoping review maps commonly reported food carcinogens and summarizes existing evidence on the role of these additives as risk factors for various cancers, such as breast, liver, lung, stomach, and colorectal (BLLSCr) cancers. Key findings highlight naturally occurring carcinogenic food contaminants (e.g., aflatoxins, heavy metals, bisphenol A, pesticide residues, polycyclic aromatic hydrocarbons (PAHs) from food processing) and economically motivated adulterants (e.g., Sudan dyes in palm oil, formaldehyde in meat) that frequently contaminate staple foods. There is evidence that these contaminants serve as a risk factor for certain cancers, especially BLLSCr cancers. Moreover, gender and socioeconomic disparities influence cancer prevalence, with men at higher risk for liver, lung, and gastric cancers, while breast cancer incidence rises among women in high-income settings. This review highlights two major contamination pathways: natural toxins and economically motivated adulterants. Meanwhile, strategies to prevent or control/reduce food contamination and associated dietary exposures to these carcinogens have been proposed. Exposure to nutritional carcinogens, as drivers of BLLSCr cancers, represents a food safety and public health challenge globally.
Arnaud Fondjo Kouam, Mayelle Mepa Mokam, Eléonore Ngounou, Ferdinand Elombo Kouoh, Rodrigue Fifen, Kerinyuy Juliene Kongnyuy and 6 more
PubMed
Objective: against gentamicin-induced hepato-renal toxicity. Materials and Methods: antioxidant activities. Then, their cytoprotective effects were assessed against gentamicin-induced cytotoxicity in primary mouse hepatocytes. Finally, mice were administered with gentamicin (20 mg/kg) and co-treated with HAG for 14 days, and histopathology, biochemical and molecular parameters related to gentamicin-induced toxicity were evaluated. Results: HAG exhibited outstanding chemical antioxidant activities and preserved hepatocytes from gentamicin-induced cytotoxicity. HAG relieved liver and kidney histopathological and biochemical changes, and enhanced the mRNA level of Nrf2 and its target gene HO-1 in gentamicin-intoxicated mice. Conclusion: HAG attenuates hepato-renal injuries induced by 14-days administration of gentamicin in mice through the activation of Nrf2-antioxidant signaling pathways.
Roméo Tsayem Fouéméné, Madjid Morsli, Thierry Ngouana Kammalac, Chloé Magnan, Cassandra Pouget, Catherine Dunyach‐Remy and 4 more
Research Square
Arnaud Fondjo Kouam, Aristide Mfifen Munvera, Jordas Casares Tchana Tchamba, Elisabeth Menkem Zeuko’o, Armelle Gaelle Kwesseu Fepa, Brice Fredy Nemg Simo and 6 more
Pharmacological Research - Reports
Jeannette Nina Magoudjou Pekam, Noella Molisa Efange, Lakshminarayana Misro, Rodrigue Keumoe, Bruno Lenta Ndjakou, Lawrence Ayong and 3 more
International Journal for Parasitology Drugs and Drug Resistance
Antimalarial resistance is a primary challenge in the treatment of malaria. The ongoing search for novel drug sources remains a critical strategy for addressing this issue. This study evaluated the blood stage antiplasmodial and cytotoxic activities of the crude extract and fractions obtained from Lepidobotrys staudtii . The crude extract and all fractions exhibited promising antiplasmodial activity (IC 50 <10 μg/mL) against all the tested Plasmodium falciparum strains ( Pf 3D7 drug-sensitive and Pf INDO resistant). Notably, the hexane and ethyl acetate fractions exhibited the highest potency, with IC 50 values of 3.73 and 3.4 μg/mL ( Pf 3D7), respectively. No cytotoxic effects were observed at concentrations of up to 500 μg/mL. The ethyl acetate fraction displayed rapid action (12 h of exposure) against the Pf 3D7 and Pf INDO strains. The ring stage parasites were particularly susceptible to the fractions, with IC 50 values ranging from 2.17 to 4.87 μg/mL ( Pf 3D7) and 2.27 to 6.27 μg/mL ( Pf INDO). Additionally, combining the fraction with standard antimalarials at fixed sub-inhibitory concentrations significantly reduced IC 50 values. Only the hexane and crude extracts stimulated reactive oxygen species (ROS) production, whereas the other fractions neutralized the ROS. The most potent ethyl acetate fraction arrested parasite developmental progression and merozoite egress. Phytochemical analyses revealed the presence of phenols, flavonoids, tannins, alkaloids, saponins, carbohydrates, glycosides, and proteins. Reverse Phase High Performance Liquid Chromatography (RP-HPLC) analysis revealed that the fractions comprised a diverse array of compounds, resulting in varying levels of parasite-killing. This study emphasizes the blood-stage antiplasmodial properties of the stem bark extract and fractions of L. staudtii , underscoring their potential as a promising source of antimalarial agents.
Fils Armand Ella, Bruno Dupon Akamba Ambamba, Frédéric Nico Njayou, Paul Fewou Moundipa
IBRO Neuroscience Reports
Background Treatment for complex multifactorial neurological disorders may benefit more from multifunctional chemicals. Dysregulation of monoaminergic pathways and neuroinflammation are typical confluence points in a range of neuropsychiatric and neurodegenerative illnesses. Polypharmacological medications that affect neuroinflammatory and monoaminergic pathways were investigated as potential targets for these diseases. The aim of this study was to investigate the in vitro and in silico multi-target neuroprotective activity of Khaya grandifololia . Methods Decoction and hydro-ethanolic extracts were prepared and screened for their ability to inhibit enzymes related to inflammation (15-lipoxygenase, LOX), neurodegeneration (monoamine oxidase, MAO), and protein glycation and fibrillation using enzymological fluorimetric assays and docking simulations. Results All extracts were able to strongly inhibit the activity of MAO as well as the glycation and fibrillation activities. Also, these extracts moderately inhibited 15-LOX activity. Conclusion These results extend the knowledge on the potential use of Khaya grandifololia to combat multifactorial disorders, giving new approaches into therapeutic avenues for neurodegenerative disease such as Alzheimer's disease.
Laure Viviane Ndam Ngoungoure, Wilfred A. Abia, Brice Vincent Ayissi Owona, Yacouba Foupouapouognigni, Ferdinand Kouoh Elombo, Herman Philipe Njitoyap Nfombouot and 4 more
Developmental Neurobiology
This comprehensive literature review was conducted to identify relevant studies on mycotoxins and brain development in children. Existing studies suggest that mycotoxin exposure during critical periods of brain development may lead to neurocognitive impairments in children. Some studies have reported associations between mycotoxin exposure and reduced cognitive abilities, impaired motor skills, and behavioral problems. Additionally, mycotoxins have been shown to disrupt neural signaling pathways and interfere with neurotransmitter function, potentially contributing to neurodevelopmental disorders. This comprehensive review has provided a comprehensive overview of the possible evidence on the association between mycotoxin exposure and brain development in children and identified areas for future research.
Marie Atsama Amougou, Fredy Brice Nemg Simo, Cedric Fossi Tchinda, Marie Moukam, Marcel Tongo‐Passo, Paul Fewou Moundipa
Health Science Reports
ABSTRACT Background Hepatitis B virus (HBV) infection is preventable through vaccination. However, healthcare workers (HCWs) are at increased risk of HBV transmission due to occupational exposure. Aims This study investigates the prevalence of HBV markers of exposure and infection, HBV genotypes, and immunity among HCWs at Yaoundé General Hospital. Methods We conducted a prospective, cross‐sectional study based on self‐administered questionnaires and blood samples collected from HCWs. HBV markers (HBsAg, anti‐HBs, anti‐HBc) and genotypes were analyzed using ELISA MONOLISA kits and hemi‐nested amplification and sequencing focusing on the HBV S region. Results Among 173 HCWs, 46.8% (81/173) were exposed (positive for anti‐HBc), 14.8% (12/81) of exposed participants were infected (HBsAg). A 9.8% (17/173) were naturally immunized (positive for anti‐HBc and anti‐HBs) and 60.7% (105/173) had acquired immunity (anti‐HBs only). Phylogenetic analysis revealed the prevalence of only HBV genotype E. Exposure to HBV and current infection was significantly associated with age group, with a significant p < 0.05 ( p = 0.0032) predominance in the 20–29 age group 60.1% (104/173) and 32.9% (57/173), respectively. Notably, low vaccine response was closely associated with function, with nurses being at higher risk (OR = 8.52; 95% CI: 3.250–10.567), whereas high vaccine immunity was observed in those who had received all 3 doses of HBV vaccine (OR = 15.861; 95% CI: 0.971–45.591). Conclusion This study revealed a significant burden of HBV infection among HCWs in Yaounde General Hospital, Cameroon. Our results highlight the ongoing risk of HBV transmission among HCWs and emphasize the importance of an active, multi‐faced approach, including vaccination programs, precautionary measures, and additional strategies, to effectively contain HBV exposure among HCWs in Cameroon.
Madeleine Yvanna Nyangono Essam, Arnaud Fondjo Kouam, Armelle Gaelle Kwesseu Fepa, Armel Jackson Seukep, Elisabeth Zeuko’o Menkem, Felicité Syntia Douanla Somene and 3 more
medRxiv
Abstract Malaria and typhoid fever remain major health issues in developing countries like Cameroon, with frequent co-infections. The potential liver damage caused by their respective causative pathogens is overlooked in health management, posing a significant risk of severe liver injury and worsening patient conditions. Accordingly, this study investigated the risk factors associated to liver damage in febrile patients with malaria, typhoid fever, or co-infection at the Obili District Medical Center and Mvog-Betsi Dominican Hospital Center, Yaoundé, Cameroon. During 8 months, 350 febrile patients were evaluated for their adherence to preventive measures concerning malaria and typhoid fever using a structured questionnaire. Blood samples were analyzed for Plasmodium species and Salmonella antibodies and liver enzyme levels were measured. Liver damage was assessed employing the Roussel Uclaf Causality Assessment Method. Risk factors for infections and liver damage were identified using Fisher’s Exact and Chi-Square tests, with significance set at P<0.05. Among participants tested, 129 (36.86%) and 106 (30.29%) were positive for malaria and typhoid, respectively, while 56 (16.00%) were co-infected. Men (58/118 and 44/118) were more affected than women (71/232 and 62/232) for both malaria and typhoid. Participants aged between 20 and 40 years were the most affected by malaria (21.4%) and typhoid fever (17.4%). The non-use of mosquito nets, presence of standing water, bushes, and garbage dumps near residences were significant risk factors (Relative risk: RR>2.1; P<0.0001) for contracting malaria or typhoid fever. The co-infection status (Chi-2 = 18.30; P<0.0001), parasite density (Chi-2 = 9.8; P=0.0074), and delay before consulting (Chi-2 = 13.23; P=0.0013) were significant risk factors for the occurrence of liver injuries. Our findings demonstrated that the alteration of liver enzyme activities, reflecting liver damages among patients with malaria, typhoid, or malaria-typhoid co-infection, is a reality and should be considered during the patient’s treatment.
Madeleine Yvanna Nyangono Essam, Arnaud Fondjo Kouam, Armelle Gaelle Kwesseu Fepa, Armel Jackson Seukep, Elisabeth Menkem Zeuko’o, Felicité Syntia Douanla Somene and 3 more
PLoS ONE
Malaria and typhoid fever remain major health issues in developing countries like Cameroon, with frequent co-infections. The potential liver damage caused by their respective causative pathogens is overlooked in health management, posing a significant risk of severe liver injury and worsening patient conditions. Accordingly, this study investigated the risk factors associated with liver damage in febrile patients with malaria, typhoid fever, or co-infection at the Obili District Medical Center and Mvog-Betsi Dominican Hospital Center, Yaoundé, Cameroon. Over 8 months, 350 febrile patients were evaluated for their adherence to preventive measures concerning malaria and typhoid fever using a structured questionnaire. Blood samples were analyzed for Plasmodium species and Salmonella antibodies and liver enzyme levels were measured. Liver damage was assessed using the Roussel Uclaf Causality Assessment Method. Risk factors for infections and liver damage were identified using Fisher's Exact and Chi-Square tests, with significance set at P < 0.05. Among participants tested, 129 (36.86%) and 106 (30.29%) were positive for malaria and typhoid, respectively, while 56 (16.00%) were co-infected. Men (49.2% and 37.3%) were more affected than women (30.6% and 26.7%) for both malaria and typhoid, respectively. Participants aged between 20 and 40 years were the most affected by malaria (21.4%) and typhoid fever (17.4%). The non-use of mosquito nets, presence of standing water, bushes, and garbage dumps near residences were significant risk factors (Relative risk: RR > 2.1; P < 0.0001) for contracting malaria or typhoid fever. The co-infection status (Chi-2 = 18.30; P < 0.0001), parasite density (Chi-2 = 9.8; P = 0.0074), and delay before consulting (Chi-2 = 13.23; P = 0.0013) were significant risk factors for the occurrence of liver injuries. Our findings demonstrated that the alteration of liver enzyme activity, reflecting liver damage among patients with malaria, typhoid, or malaria-typhoid co-infection, is a reality and should be considered during the patient treatment.
Doriane Perlise Lienou, Corinne Raïssa Ngnameko, Fils Armand Ella, Marie Atsama Amougou, Arnaud Fondjo Kouam, Jacqueline Njikam Manjia and 3 more
Exon.
Urease is an enzyme that plays a significant role in the pathogenesis of Helicobacter pylori responsible for numerous health issues, among which chronic gastritis, peptic ulcer disease, gastric neoplasia and even stomach cancer. Therefore, targeting urease represents a key strategy to attenuate gastritis induced by H. pylori. Khaya grandifoliola (KG) and Entada africana (EA) were prepared using methylene chloride/methanol (1:1, v/v). After that, the extracts were fractionated using a gradient of solvent and the anti-urease activities of crude extracts and fractions was evaluated. Mechanism of inhibition of urease by the most active fractions was determined using kinetic method. Polyphenols and flavonoids contents were determined. Extracts and fractions of KG and EA exhibited a significant inhibition of urease activity. The half inhibitory concentration (IC50) of KG (31.61 ± 0.23 µg/mL) and EA (35.70 ± 0.14 µg/mL) showed no significantly difference (P > 0.05) to the reference Thiourea (30.37 ± 0.30 µg/mL). In addition, the kinetic study revealed that the methanolic fraction (FMeOH) of KG and EA strongly inhibited the activity of urease with IC50 values of 31.60 ± 1.25 and 29.00 ± 1.05 µg/mL respectively. These fractions exhibited mixed-type inhibition with Kic and Kia values of 9.96 and 91.15 µg/mL for KG and 13.24 and 226.59 µg/mL for EA respectively. Both extracts contain phenolic compounds. Overall, this study indicated a high anti-urease activity of the methanolic fraction of KG and EA. Each fraction exerts a mixed inhibition on urease activity.
Younous Yaya Charfadine, Rodolphe Koularambaye, Sara Nathalie Edjenguèlè Béboy, Rodrigue Fifen, Yannick Sani Jignoua, Paul Désiré Djomeni Dzeufiet and 1 more
Journal of Drug Delivery and Therapeutics
Background: Androgen deficiency is the most common disorder of reproductive function and can lead to male sexual disorders. Objective: This study was designed to evaluate the androgenic effects of Pycnanthus angolensis (Welw.) Warb in hemicastrated rats. Materials and methods: Forty-two male rats were divided into 6 groups of 7 rats each, including a group of uncastrated rats that received distilled water (10 ml/kg); a group of castrated rats that received 10 ml/kg of distilled water; a group of castrated rats that received testosterone enanthate (3 mg/kg BW) per week intramuscularly; and 3 groups of castrated rats that received 43, 86 and 172 mg/kg of the aqueous extract of Pycnanthus angolensis, respectively. After 14 days of oral treatment, the rats were killed by decapitation. The blood was collected and the androgen-dependent organs were collected for histological sectioning, and biochemical analysis. The tail of the epididymis was used to assess sperm quality. Results: Treatment with the aqueous extract at doses of 43 and 86 mg/kg, significantly improved the sexual behavior of castrated rats, with increases of 25.92% and 22.74% intromissions frequency, and 67.06% and 56.46% mount frequency, compared to those in the castrated rats which did not receive any treatment. The extract also enhanced sperm quality in castrated rats. Both doses also significantly increased serum testosterone levels with rates of 45.07% and 49.00%, respectively; compared to those in the negative control group. Conclusion: In view of the aforesaid results, Pycnanthus angolensis (Welw.) Warb could be considered as a promising natural agent in hypogonadism management. Keywords: Androgen, hypogonadism, castrated male rats, unilateral castration, Pycnanthus angolensis (Welw.) Warb
Rodolphe Koularambaye, Sara Nathalie Edjenguèlè Béboy, Yannick Sani Jignoua, Alfloditte Flore Feudjio, Arnaud Cyrille Choupo, Fabiola Jenny Massah and 2 more
Journal of Complementary and Alternative Medical Research
Aims: Pycnanthus angolensis (Welw.) Warb. also known as “Etengué” in the Baka language, is a medicinal plant used by the Baka Pygmies of Cameroon to treat erectile dysfunction. This study aimed to evaluate the androgenic activity and subchronic toxicity of the aqueous extract of Pycnanthus angolensis wood. Study Design: Experimental design. Place and Duration of Study: Laboratory of Biochemistry, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, between November 2022 and October 2023. Methodology: Twenty-five male Wistar strain rats were divided into 5 groups of 5 rats each including a positive control group that received testosterone enanthate (5 mg/kg) intramuscularly once a week; a normal control group that received distilled water (10 ml/kg) and three test groups which received 134 and 267 and 533 mg/kg of the aqueous extract of Pycnanthus angolensis daily per os. On the 29th day, the animals were killed, and several biochemical parameters were assessed for androgenic properties. Results: At a dose of 134 mg/kg, the extract significantly increased (p<0.05) the levels of testicular cholesterol, testosterone and serum prostatic acid phosphatase activity compared to those of the normal control. A toxicity study showed that at doses of 134 and 267 mg/kg, the extract did not induce any significant variation (p>0.05) in the creatinine level, but a significant reduction (p<0.05) in of aspartate and alanine aminotransferase activities was recorded. Histopathology revealed destruction of testicular spermatozoa at a dose of 533 mg/kg compared to that of the controls. Conclusion: These results showed that at a dose of 134 mg/kg, the aqueous extract of Pycnanthus angolensis (Welw.) Warb. wood is capable of stimulating the production of androgens and is tolerated by the rat's body. Our results justified the traditional use of this plant for the treatment of male infertility and erectile dysfunction.
Jacqueline N. Manjia, Emmanuel Mfotie Njoya, Harishchander Anandaram, Aristide Mfifen Munvera, Frank Abimbola Ogundolie, Pierre Mkounga and 3 more
Revista Brasileira de Farmacognosia
Yannick Sani Jignoua, Sara Nathalie Edjenguèlè Béboy, Paulin Teko Keumedjio, Marie Louise Coute-Chère Mbog, Paul Fewou Moundipa
Asian Journal of Pharmacy and Pharmacology
Objective: Aluminum chloride can induce toxicity of the reproductive system leading to infertility which is a real public health problem.This study was undertaken to investigate the effect of Engl.& Diels in vivo Terminalia superba aqueous extract on aluminum chloride-induced reprotoxicity in male rats.Thirty male Materials and methods: Wistar rats of 12 weeks each, weighing 160 -180 g were intraperitoneally administered aluminum chloride (20 mg/kg, body weight) for 56 days.The rats were subsequently orally treated for 56 days with Engl.& Diels Terminalia superba aqueous bark extract at doses of 43 and 86 mg/kg and a coadministration of vitamin E (100 mg/kg) and zinc (50 mg/kg).Then, the rats were killed, and blood, testes, epididymis, seminal vesicle and prostate were removed for histological and biochemical analysis.Aluminum chloride caused significant decreases in the sexual performance of the male Results: rats, sperm quality, catalase activity and glutathione levels (P < 0.05).The serum testosterone and fructose levels were also significantly lower in the intoxicated group (P <0.05) than in the normal control group, with decreases of 91.25 % and 8.80 % respectively.In addition, histological lesions were observed in the testes, epididymis and prostate of the intoxicated group.Our results revealed that the aluminum chloride-induced reprotoxicity was reversed by the aqueous extract of Engl.& Diels.Oral administration of an aqueous extract of Terminalia superba Terminalia Conclusion: superba ; Engl.& Diels at the dose of 86 mg/kg, can alleviate the aluminum chloride-induced reprotoxicity in male rats.
Sara Nathalie Edjenguèlè Béboy, Paulin Teko Keumedjio, Sylvain Nsangou Pechangou, Yannick Sani Jignoua, Dieudonné Pascal Djamen Chuisseu, Paul Fewou Moundipa
Asian Journal of Research in Medical and Pharmaceutical Sciences
In the Southern region of Cameroon, some medicinal plants are used for the treatment of the male reproductive system disorders; including Palisota ambigua, Rauvolfia macrophylla, Terminalia superba, Pycnanthus angolensis, Pausynistalia yohimbe and Schumanniophyton magnificum. The aim of our study was to investigate the antioxidant properties of the ethanolic extracts of these plants, as well as their phytochemical constituents and their effects on nitric oxide release. Rat peritoneal macrophages were isolated and used to assess in vitro effects of plant extracts on nitric oxide release. Then, antioxidant properties of alcoholic extracts of the plants were screened through 2,2-diphenyl-1-picrylhydrazyle test, total antioxidant capacity test and ferric reducing power test and lipid peroxidation inhibition test. Phytochemical constituents, total phenol and flavonoid contents were also investigated. Results showed that only the extracts of T. superba and P. yohimbe were found to be strong 2,2-diphenyl-1-picrylhydrazyle free radical scavengers with low EC50 (8.40 [8.31, 8.53]; 17.73 [17.67, 17.74] µg of plant extract/mol 2,2-diphenyl-1-picrylhydrazyle). The plants extracts exhibited better inhibitions of the lipid peroxidation in concentration-dependent manner; especially R. macrophylla with an IC50 of 2.38 (2.13, 4.92) µg/mL. No significance difference was observed neither among the total phenolic nor flavonoids contents of the plant extracts. Extract of T. superba exhibited strong antioxidant properties. Though, the extracts of R. macrophylla and P. angolensis and S. magnificum were also able to protect against lipid peroxidation and free radicals. The phytochemical screening revealed the presence of alkaloids, flavonoids, phenols, tannins, coumarins, glycosids in most of the plants extracts. These properties sustain their use for treatment of male infertility and erectile dysfunction.
Sara Nathalie Edjenguèlè Béboy, Louise Marie Coûte-Chère Mbog, Yannick Sani Jignoua, Paulin Teko Keumedjio, Patrick Kevin Motto Feune, Paul Fewou Moundipa
The Journal of Phytopharmacology
Background: Erectile dysfunction is the inability to achieve and maintain an adequate erection for sexual performance. Pycnanthus angolensis (Welw.) Warb. is a medicinal plant used by the traditional healers of the Southern region of Cameroon to manage male infertility and especially erectile dysfunction. Aim and objectives: This study aimed at investigating the effects of aqueous extract of Pycnanthus angolensis wood were investigated on paroxetine-induced erectile dysfunction in male rats. Material and methods: Thirty Wistar albino male rats (160-180 g) were randomly distributed into six groups of five animals each. Erectile dysfunction was induced in 5 groups for 21 days by oral administration of paroxetine (10 mg/kg), once a day. After induction, rats were orally treated during 14 days with three doses of plant extract (43, 86 and 172 mg/kg) except 2 groups which were given distilled water and sildenafil (5 mg/kg), respectively. Sexual behaviors were monitored on days 1, 4, 7, and 14 by pairing male rats to receptive females. After 14 days- treatment, the rats were killed by decapitation under ether anesthesia. The reproductive organs were collected for histological and biochemical analysis. Results: Paroxetine induced erectile dysfunction characterized by a significant decrease (p<0.05) in sexual arousal and performance of male rats. Nevertheless, this erectile dysfunction was improved by administration of the aqueous extract of Pycnanthus angolensis at the different doses. The administration of paroxetine significantly (p<0.05) reduced the nitric oxide level by 66.67% when compared to the distilled water-group. After 14 days-treatment, the extract induced significant increases (p<0.05) in the sexual performance parameters (mounts, intromissions and ejaculations frequency) as well as in the sexual arousal of the male rats. Results were markedly pronounced with the plant extract at the doses of 86 and 172 mg/kg. The nitric oxide levels in the erectile dysfunction-induced rats with paroxetine were restored after treatment with the plant extract. The degenerated seminiferous tubules and the low density of spermatozoa observed in the histological sections of the erectile dysfunction-induced rats with paroxetine, were restored after treatments with sildenafil and the aqueous extract at either doses (43, 86 and 172 mg/kg). Conclusions: Aqueous extract of Pycnanthus angolensis (Welw.) Warb alleviated the paroxetine-related erectile dysfunction by enhancing sexual behavior and the production of nitric oxide. In view of the abovementioned results, Pycnanthus angolensis (Welw.) Warb could be considered as an alternative treatment in the erection dysfunction management.
Sandra Olivia Magne Ghomsi, Sylvain Nsangou Pechangou, Regine Sandra Maafo, Hippolyte Tene Mouafo, Agbor Kingsley Etchu, Felix Charles Bilong Bilong and 1 more
Veterinary and Animal Science
The study aimed to assess the digestibility, growth performance, and selected biochemical and hematological parameters of Bandjock Local pigs (BLP) and Duroc X Large White pigs (DLW). We hypothesize that the use of local ingredients in diet formulation associated to improved rearing conditions, enhance the growth performance, digestibility, biochemical and hematological parameters of BLP. The trial involved dividing twenty-four eight-week-old weaner pigs into two groups. Each group was randomly assigned to separate pig units. Animal management and feeding were consistent between both groups. The trial lasted for 120 days during which the growth performance, the digestibility of ingested nutrients, and biochemical and hematological parameters were evaluated. The results indicate that DLW pigs registered a weight gain (46.56±5.19 kg) significantly higher than BLP pigs (34.02), with a statistically similar feed conversion ratio. Except for albumin which was significantly higher in DLW and urea in BLP, there were no significant differences (p>0.05) in total protein, cholesterol, globulin, triglycerides, creatinine, AST, and ALT as well as hematological parameters between the breeds. However, the exotic DLW had a relatively high mean blood platelets and white blood cell concentration. Although the fecal nitrogen was higher in BLP and the urinary nitrogen was lower in the DLW, there were significant differences (p<0.05) for urine, fecal, and total excreted nitrogen in both breeds. The lowest scores in nutrient digestibility were recorded with BLP compared to DWL, except for crude fibers. The results of this study demonstrated that using diet formulated with local ingredients and improved rearing conditions, Cameroonian local indigenous pigs have a better productivity compared to exotic breeds. It suggests that efforts should be made by authorities to promote and valorize the rearing of indigenous pigs in complement to exotic pig breeds in view of strengthening the Cameroonian pig industry.
Wilfred A. Abia, Angèle N. Tchana, Doumani Djonabaye, Bojan Šarkanj, Euloge Yiagnigni Mfopou, Chibundu N. Ezekiel and 6 more
World Mycotoxin Journal
Abstract In Cameroon, dietary staples are frequently contaminated with diverse toxic fungal metabolites, known as mycotoxins. Aflatoxins and fumonisins are a public health concern, particularly concerning cancer and/or early life stunting. Mycotoxin mixtures are predicted from food measures; and this study reports the levels and frequencies of urinary mycotoxin biomarkers in Cameroonian adults. A single first void urine sample was collected from 89 adults from Yaoundé, Cameroon. Urine samples were tested for eight distinct mycotoxins using measures of both parent compounds and/or their metabolites by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Altogether, seven distinct mycotoxins, aflatoxin, fumonisin, deoxynivalenol, zearalenone, nivalenol, ochratoxin A, and citrinin, (or their metabolites) were observed in urine samples. At least one mycotoxin was detected in all of the urine samples, 87 (98%) of which were above the limit of quantitation. Aflatoxin M 1 was detected in 42% (n.d.-0.21 μg/l) of samples of which about a quarter additionally contained fumonisin B 1 . Of the remaining toxins deoxynivalenol (78%), zearalenone (99%), ochratoxin A (95%), nivalenol (53%), and citrinin (87%) were present in the samples. Alternariol was not detected in any sample. Mixtures of mycotoxins in the samples were frequently observed with 64 samples (72%) containing more than five mycotoxin exposure biomarkers. Estimates of intake exceeded the TDIs for fumonisin B 1 (n = 4), deoxynivalenol (n = 1) and zearalenone (n = 2), no TDI is set for aflatoxin. This study reveals frequent co-exposure of Cameroonian individuals to a complex mixture of toxic and carcinogenic mycotoxins, with mixtures of aflatoxin and fumonisin being a particular priority from a public health standpoint.
Brice Ayissi Owona, Arnaud Mary, Angélique Nicolas Messi, Kishore Aravind Ravichandran, Joséphine Ngo Mbing, Emmanuel Pegnyemb and 2 more
Molecular Neurobiology
Jacqueline Njikam Manjia, Apeksha Joshi, Emmanuel Mfotie Njoya, Kapil K. Upadhyay, Corinne Raïssa Ngnameko, Lyndy J. McGaw and 3 more
Current Drug Research Reviews
`Background: Harungana madagascariensis (HM) and Psorospermum aurantiacum (PA), used traditionally for skin care, have been reported to upregulate the expression of intracellular antioxidant genes, thereby preventing melanoma and protecting fibroblast cell lines from Ultraviolet B (UVB)-induced intracellular oxidative stress. Aims: This investigation aimed to identify major compounds in bioactive fractions using bioassay- guided fractionation. Methods: The anti-inflammatory effect of fractions was determined by measuring their inhibitory activity on 15-lipoxygenase and nitric oxide (NO) in lipopolysaccharide-stimulated RAW 264.7 macrophage cells. Additionally, the anti-aging efficacy of the fractions was determined by assessing the expression of markers for the aging process, i.e., expression of tyrosinase (TYR), tyrosinase-related protein-1 (TRP-1), procollagen type-1 (COL1A1), and matrix metalloproteinase- 1 (MMP-1) in UVB-induced photoaging in skin cell-lines. Furthermore, UHPLCMS- based identification of the bioactive compounds from the most prominent fraction was also carried out. Results: Hexane fraction of HM significantly inhibited (p < 0.05) the 15-lipoxygenase (IC50 = 46.80 μg/mL) and NO production (IC50 = 66.55 μg/mL), whereas hexane fraction of PA was effective (p < 0.05) in inhibiting 15-lipoxygenase activity (IC50 = 27.55 μg/mL). Furthermore, the hexane fraction of HM and methanol fraction of PA were significantly effective (p < 0.05) in reverting the UVB-mediated altered expressions of MMP-1, TYR, TRP-1, and COL1A1. Furthermore, hexane fraction of HM revealed the presence of harunganin and betulinic acid, whereas vismion D, vismin, kenganthranol B, and bianthrone 1a were identified from the methanol fraction of PA. Conclusion: Overall, the hexane fraction of HM and methanol fraction of PA displayed effective anti-aging activities, with additional anti-inflammatory effects.
Fredy Brice Nemg Simo, Urmes C. Teagho, Serika Marshall Atako, Brice Tiwa Lontsi, Brice Vincent Ayissi Owona, Maurice Demanou and 7 more
Acta Tropica
Arnaud Fondjo Kouam, Ibrahim Njingou, Nina Jeannette Pekam Magoudjou, Hamed Bechir Ngoumbe, Philipe Herman Nfombouot Njitoyap, Elisabeth Menkem Zeuko'o and 2 more
Pharmaceutical Science Advances
The use of N-acetylcysteine against acetaminophen(APAP)-induced hepatotoxicity, a leading cause of liver injury, has several drawbacks, including short therapeutic windows. Khaya grandifoliola (Meliaceae) has been traditionally used to manage liver-related diseases, and many reports have confirmed its hepatoprotective properties. However, its therapeutic potential as an antidote against APAP-induced hepatotoxicity has yet to be proven in a clinically relevant model. This study aimed to verify the efficacy of delayed treatment with the hydroethanolic extract of K. grandifoliola (KgE) in suppressing the early injury phase of APAP pathophysiology. KgE was analyzed using HPLC/UV. Acute oral toxicity tests were conducted in mice to determine the therapeutic dose of KgE. Mice were treated with 300 mg/kg APAP; 1h and 12h later, they were treated with either predetermined doses of KgE or 20 mg/kg c-Jun N-Terminal Kinase (JNK) inhibitor SP600125, which served as a reference antidote. At 6h and 24h after APAP treatment, the parameters of liver damage and mitochondrial dysfunction, phosphorylation of JNK, and mitochondrial translocation were assessed. KgE at a dose of 5000 mg/kg was safe for mice. Accordingly, 100, 200, and 400 mg/kg were selected as curative treatments. Delayed administration of KgE reversed the histopathological changes in the liver, inhibited serum levels of alanine aminotransferase, reduced the liver content of nitric oxide and malondialdehyde, and restored hepatic glutathione pools and superoxide dismutase and catalase activities in APAP-intoxicated mice. Moreover, KgE prevented APAP-induced JNK phosphorylation and p-JNK mitochondrial translocation and rescued the activities of mitochondrial enzyme complexes II and V. HPLC/UV analysis revealed the presence of gallic acid, Quercetin and Silibinin, with retention times of 3.77, 11.63 and 11.95 min as the major active ingredients present in KgE. Our findings demonstrate that post-treatment with KgE protects the mouse liver from APAP-hepatotoxicity through the inhibition of JNK activation and mitochondrial dysfunction.
Faustin Pascal Tsagué Manfo, Collins Nimako, Edouard Akono Nantia, Christian Fusi Suh, Shu Policap Chenwi, Fidelis Cho‐Ngwa and 4 more
Environmental Toxicology and Chemistry
Pesticides, especially the newly developed neonicotinoids, are increasingly used in many countries around the world, including Cameroon, to control pests involved in crop destruction or disease transmission. Unfortunately, the pesticides also pose tremendous environmental problems because a predominant amount of their residues enter environmental matrices to affect other nontargeted species including humans. This therefore calls for continuous biomonitoring of these insecticides in human populations. The present study sought to assess the neonicotinoid insecticide exposures in two agrarian regions of Cameroon, the South-West region and Littoral region. The study involved 188 men, including 125 farmers and 63 nonfarmers. Spot urine samples were obtained from these subjects and subjected to liquid chromatographic-tandem mass spectrometric analysis for concentrations of neonicotinoid compounds, including acetamiprid, clothianidin, dinotefuran, imidacloprid, thiacloprid, nitenpyram, thiamethoxam, and N-dm-acetamiprid. Neonicotinoid compounds were detected in all study participants, and residues of all the screened pesticides were detected among participants. N-dm-Acetamiprid and imidacloprid were the most prevalent among the subjects (100.0% and 93.1%, respectively), whereas nitenpyram was less common (3.2%). The median values of imidacloprid and total urinary neonicotinoid concentrations were elevated among farmers (0.258 vs. 0.126 µg/L and 0.829 vs. 0.312 µg/L, respectively). Altogether the findings showed that both the farmer and nonfarmer study populations of Cameroon were exposed to multiple residues of neonicotinoids, with relatively higher levels of pesticides generally recorded among farmers. Although exposure levels of the neonicotinoids were generally lower than their respective reference doses, these results warrant further research on the health risk evaluation of multiple residues of the pesticides and reinforcement of control measures to minimize the exposure risks, especially among farmers. Environ Toxicol Chem 2024;43:952-964. © 2024 SETAC.
Joseph Tchamgoue, Sylvain Nsangou Pechangou, Abdul Rashid Issahaku, Yvan Anderson T. Ngandjui, Anke Wilhelm, Eutrophe Le Doux Kamto and 2 more
ChemistrySelect
Abstract Numerous anti‐inflammatory agents are used nowadays to relieve daily aches and pain. However, their severe side effects often limit their therapeutic use. In this study, we investigate the anti‐inflammatory activity of the crude leaves extract of Mallotus oppositifolius and five of its phloroglucinol derivatives ( MO1 – MO5 ). From spectroscopic and spectrometric analysis, the compounds were identified as mallotojaponin B ( MO1 ), mallotojaponin D ( MO2 ), acronyculatin U ( MO3 ), acronyculatin T ( MO4 ), and mallotojaponin C ( MO5 ). A primary macrophage culture activated by Saccharomyces cereviseae (SC) was used to evaluate the anti‐inflammatory activity of the crude extract and isolated compounds which were found to be nontoxic to primary macrophages at concentrations ranging from 0.1–50 µg/mL. In addition, the tested samples inhibited the 5‐lipoxygenase activity, nitric oxide (NO), and tumor necrosis factor alpha (TNF‐α) production by viable primary mouse macrophages in a concentration‐dependent manner with MO1 and MO3 exhibiting the highest in vitro anti‐inflammatory activities. Moreover, in silico studies were performed with the isolated compounds to evaluate their binding capacities/scores against the main enzymes involved in inflammation mediation in human cells. The compounds showed good binding affinities to critical anti‐inflammation targets particularly mallotojaponin C ( MO5 ) (−44.55 Kcal/mol) and acronyculatin T ( MO4 ) (−41.44 Kcal/mol) which showed the highest affinity for 5‐lipoxygenase.
Arnaud Fondjo Kouam, Florence Déclaire Mabou, Lifeng Fu, Roméol Romain Koagne, Yan Li, Brice Ayissi Owona and 7 more
South African Journal of Botany
Highly pathogenic coronaviruses, including the Middle East Respiratory Syndrome Coronavirus (Mers-CoV) and Severe Acute Respiratory Syndrome Coronavirus-2 (Sars-CoV2), have recently emerged and represent a serious threat to global health. Accordingly, a search for potent inhibitors against coronavirus diseases is warranted. Therefore, this study aimed at identifying potential inhibitors from Crinum distichum against the papain-like protease (PLpro), an important antiviral target due to its essential role in viral replication. A bacterial expression system was used for the recombinant expression of Mers-CoV-PLpro and Sars-CoV2-PLpro which was used to assess the inhibitory effect of compounds isolated from C. distichum against their proteolytic and deubiquitinating (DUB) activities. Then, the inhibition mechanism of hit compounds was determined through enzyme kinetic studies. Protein-ligand stability was assessed by Differential Scanning Fluorometry and Molecular docking was used to predict the possible molecular interactions. Five compounds, namely (2 S )-4´,7-dimethoxyflavan (CDS1), (2 S )-4´‑hydroxy-7-methoxyflavan (CDS2), Hippadine (CDS3), (2 R )-4´‑hydroxy-5,7-dimethoxyflavan (CDS4) and Hippacine (CDS5) were tested in this study. They markedly inhibited both the proteolytic and deubiquitinating activities of CoV-PLpro. Their IC 50 values were in the low micromolar range. The most potent inhibitors were CDS3 and CDS4, with IC 50 values of 9.28 and 6.45 µM, and 11.63 and 6.10 µM against the proteolytic and DUB activities of Mers-CoV-PLpro and Sars-CoV2-PLpro, respectively. They exert their inhibitory effect through competitive and non-competitive inhibition mechanisms. These compounds induced the instability of the enzymes by reducing their melting temperature and molecular docking analysis revealed several molecular interactions between the compounds and various amino acids of the enzymes. Overall, our findings suggest C. distichum active constituents to be promising candidates for development into potential inhibitors against coronavirus .
Espérance Argentine Mbompieze Téfandjam, Sylvain Nsangou Pechangou, Sara Nathalie Edjenguèlè Béboy, Brice Enang, Cynthia Paola Demeni Emoh, Jean Paul Assam Assam and 1 more
The Journal of Phytopharmacology
Intestinal amoebiasis (IA) remains a global public health concern. It is often confused with an inflammatory bowel disease, and is caused by Entamoeba histolytica. Although it is more widespread in tropical countries, IA is increasingly becoming a subject of concern in so-called developed countries. The limits of conventional therapy and the concern to promote phytotherapy in a sustainable and ecological manner inspired this work, during which the anti-amoebic and anti-inflammatory potential of endophyte fungi extracts isolated from Codiaeum variegatum were evaluated. C. variegatum leaves and bark was harvested at the University of Yaounde 1. Those two fragments undergo surface decontamination then were placed in petri dishes containing PDA (Potato Agar Dextrose) supplemented with amoxicillin. The cultures obtained were then subcultured in SDA (Sabouraud Dextrose Agar) and CZA (CZapek dextrose Agar) media. The resulting growth was observed using an optical microscope with an x40 objective for grouping on the basis of macroscopic and microscopic characteristics. Screening of extracts of these fungi by the Trypan blue counting method on clinical isolates of E. histolytica, made it possible to retain 4 extracts (6, 8, 14, 18) of fungi with anti-amoebic activity. Subsequently, the anti-inflammatory potential of these extracts was evaluated on a primary culture of macrophages activated by Saccharomyces cerevisiae through the inhibition of nitric oxide (NO) production, NADPH oxidase activity, and activation of alkaline phosphatase (ALP). From that culture, 28 endophytic fungi were isolated, 13 belonging to 7 genus (Absidia sp, Alternaria sp, Aspergillus sp, Trametes sp, Trichoderma sp, Fusarium sp and Geotrichum sp). Anti-amoebic tests showed that extract 14 was the most active with an inhibitory concentration 50 (IC50) of 289.87±18.57; 207.73±22.36 and 87.79±12.51µg/mL respectively after 24, 48 and 72 hours of incubation. Chemical screening of the extracts revealed the majority presence of flavonoids in the 4 extracts (6, 8, 14, and 18). The anti-inflammatory tests of these 4 extracts revealed better anti-inflammatory activity in extract 6 (IC50= 95.94 ± 21.07 µg/mL for NO; IC50= 11.78±0.27 µg/mL for NADPH oxidase). Extract 14 had the best effect on the inhibition of NO production (IC50 = 8.56±2.13 µg/mL) and on the inhibition of the growth of trophozoites. Endophytic fungi extract from C. variegatum have demonstrated promising anti-amoebic and anti-inflammatory potential and therefore deserve special attention for the development of natural and ecological alternative treatment.
Yannick Sani Jignoua, Sara Nathalie Edjenguèlè Béboy, Sylvain Nsangou Pechangou, Angèle N. Tchana, Paul Fewou Moundipa
Journal of Complementary and Alternative Medical Research
Aims: Terminalia superba Engl. & Diels, also known as “Mbonga”, is a medicinal plant used by the “Baka” Pygmies of Cameroon for the management of male infertility. Many studies have demonstrated its anti-inflammatory, antiulcerative, antidiabetic and antioxidant properties. No scientific evidence to date has been provided on this treatment. Aluminium chloride is an endocrine disruptor that can induce male infertility through various mechanisms. The present study was designed to assess the protective effect of the bark-aqueous extract of Terminalia superba against aluminium chloride-induced reproductive toxicity in male rats. Study Design: Experimental design. Place and Duration of Study: Laboratory of Pharmacology and Toxicology, Faculty of Science, University of Yaoundé I, between November 2021 and October 2022. Methodology: Thirty-five Wistar albino rats were divided into groups of 5 animals each including untreated group. After induction of reprotoxicity by an intraperitoneal administration of aluminum chloride (20 mg/kg, body weight) for 56 days, 20 rats were subsequently orally treated for 56 days with the bark-aqueous extract at doses of 43 and 86 mg/kg as well as a co-administration of vitamin E (100 mg/kg) and zinc (50 mg/kg). The first group served as the normal control group and the last groups received only the extract (43 and 86 mg/kg). On the last day, sexual behaviour tests were performed, then rats were killed the next day. Assessment of biochemical markers of oxidative stress, histopathological studies and sperm analysis were performed. Results: Aluminium chloride induced significant decreases (P <0.05) in sperm quality, sexual performance of the male rats, catalase activity and glutathione levels. The aqueous extract of Terminalia superba reversed the toxic effects of aluminium chloride by improving the sexual behaviour of male rats and increasing the level of reduced glutathione as well as the catalase activity in their testis and epididymis. Conclusion: Terminalia superba has an enhancing effect against aluminium chloride-induced toxicity in male rats, and could therefore be an alternative to solve reprotoxicity problems.
Arnauld Efon-Ekangouo, Hugues C. Nana-Djeunga, Philippe Nwane, Narcisse Nzune-Toche, Jeanne C Sondi-Dissake, Guilhem Sempéré and 5 more
Infection Genetics and Evolution
Arthropod microbiota plays an important role in host physiology, and there is growing interest in using vector symbionts to modify vector competence and control parasite transmission. This study aims to characterise the blackfly Simulium damnosum s.l. gut microbiota and to explore possible associations with various bio-ecological determinants of the Onchocerca volvulus establishment and the transmission in blackfly. Adult female blackflies were caught in three Cameroonian health districts belonging to different bioecological zones endemic for onchocerciasis. Flies were dissected and qPCR screened for Onchocerca volvulus infection. The diversity of the blackflies gut microbiota was assessed by high-throughput sequencing of the V3-V4 hypervariable region of the bacterial 16S ribosomal RNA. Subsequent metataxo-genomic, multivariate, and association analysis were used to investigate the variables that influence the microbiota diversity. Transmission index rates ranging from 20.7 to 6.0 % and 6.2to 2.0 % for infection and infectivity rates, respectively, indicate ongoing transmission of onchocerciasis across all surveyed health districts. The identified bacterial taxa were clustered into four phyla, five classes, and 23 genera. The S. damnosum s.l. gut microbiota was dominated by Wolbachia and by Rosenbergiella in Wolbachia-free Simulium. Significant differences were observed in the diversity of S. damnosum s.l. microbiota concerning parity status (P = 0.007), health district of origin (P = 0.001), and the presence of the Onchocerca volvulus. Simulium from the Bafia health district also showed increased bacterial diversity between two consecutive years (P = 0.001). Four bacterial taxa, including Serratia, were associated with the absence of the O. volvulus infection. These results indicate that S. damnosum s.l. from different onchocerciasis foci in Cameroon, exhibit distinguishable gut microbial compositions which are dynamic over time. Some bacterial species are associated with the O. volvulus infection and could be further investigated as biological target/tool for vector modified-based onchocerciasis control.
Patrick Kevin Moto Feune, Paulin Teko Keumedjio, Sara Nathalie Edjenguèlè Béboy, Yannick Sani Jignoua, Fabiola Jenny Massah, Sylvestre Tsila Saidou and 3 more
Journal of Ethnopharmacology
Christian Fusi Suh, Faustin Pascal Tsagué Manfo, Edouard Akono Nantia, Ndie Ngalame Dionysius, Jude Nkeng Fombele, Daisy Lum Suh and 3 more
Drug and Chemical Toxicology
The use of agrochemicals as plant growth regulators, pesticides, and soil fertilizers can result in insults among farmers and other non-targeted organisms. The adverse effects of agrochemicals are of global concern, though limited studies have delineated their toxicity on blood cells and inflammatory parameters in Fako division in Cameroon. This study examined the impact of occupational exposure on haematological and inflammatory parameters among farmers in Fako division. Briefly, 165 farmers who occupationally applied agrochemicals and a reference population of 75 non-farmers were interviewed on types of agrochemicals used, knowledge and safety during use of agrochemicals, as well as related symptoms of exposure. Serum cholinesterase (acetylcholinesterase and butyrylcholinesterase) activities were measured as biomarkers of exposure to agrochemicals. Complete blood count and serum levels of interleukin-6 (IL-6) and nitric oxide (NO) were determined as haematological and inflammatory biomarkers. Results disclosed frequent use of insecticides, fungicides, herbicides and fertilizers with neglect of personal protective equipment. Reported symptoms of exposure to agrochemicals were consistent with decrease in cholinesterase activities. Exposure to agrochemicals decreased erythrocyte count and red cell distribution width, as well as increased mean cell volume, mean corpuscular hemoglobin, serum levels of NO and IL-6 in farmers; suggesting anemia and increased cellular inflammation. In conclusion, the use of agrochemicals resulted in inhibited cholinesterase activities, induced anemia, and promoted cell inflammation in farmers. These findings call for more sensitization and training of the farmers to minimize agrochemical exposure and related health hazards.
Marie Louise Medoua, Sylvain Nsangou Pechangou, Brice Enang, Assam Assam Jean Paul, Emmanuel Mfotie Njoya, Frédéric Nico Njayou and 1 more
Asian Journal of Research in Medical and Pharmaceutical Sciences
Aims: The present work aimed to evaluate the anti-amoebic, antibacterial, and anti-inflammatory potential of three natural polyketides from Phomopsis sp. CAM212.
 Study Design: Clinical isolates of E.histolytica, E.coli ATCC25922 strain, primary peritoneal mouse macrophages and three polyketides were used.
 Places and Duration of Study: Laboratory of Pharmacology and Toxicology, Laboratory of Medical Microbiology, Faculty of Science, University of Yaounde 1 between May and December 2022.
 Methodology: During this work, we evaluated the ability of three natural polyketides from Phomopsis sp to inhibit the growth of germs responsible for amoebic and bacillary dysentery. First, the anti-amoebic activity was carried out on clinical isolates of E. histolytica in polyxenic culture. Subsequently, we evaluated the antibacterial potential on a strain of E. coli ATCC25922. Finally, the anti-inflammatory potentials were evaluated on a primary culture of SC activated macrophages through inhibition of nitric oxide (NO) production, activation of phosphatase alcaline (ALP) and inhibition of 5-lipoxygenase (5-LOX).
 Results: It emerges from this work that among compounds, phomopsinin B, presented the highest anti-amoebic potential (84.4 % inhibition after 72h) and the highest antibacterial potential (MIC=12.5µg/mL and MBC/MIC=2). Phomopsini A and phomopsini A acetate showed moderate anti amoebic and antibacterial potentials. However, all these activities remain lower than that of metronidazole and ciprofloxacin (90% of amoebic inhibition after 72h; MIC=0.72µg/mL and MBC/MIC=4). Subsequently, all tested compounds were nontoxic on primary macrophages. Phomopsinin B exhibited a great anti-inflammatory potential through the inhibition of NO production (IC50=1.72±0.91µg/mL); inihibition of 5-LOX activity (IC50=36.97±7.12µg/mL) and activation of ALP activity (IC50=0.13±0.01µg/mL) as compared to Baicalin the standard. The anti-inflammatory potential of phomopsinin A and phomopsinin A acetate were lower compared to baicalin.
 Conclusion: Ultimately, among compounds tested, phomopsinin B exhibited the best anti-amoebic, antibacterial and ant-inflammatory potential similar to the respective standards within the limits of the tests carried out.
Sylvain Nsangou Pechangou, Charifa Ngbetkom Mandou, Carine Matsigang Fondjou, Vigny Sayal Ngohoba, Edie Brice Enang, Ibrahim Njingou and 3 more
Journal of Biosciences and Medicines
Codiaeum variegatum has been widely investigated for its biological proprieties ranging from the antiamoebic potential to the phytochemical analysis. The aim of the present study was to evaluate the anti-inflammatory potential of C. variegatum leaf extracts and fractions. A primary macrophage culture activated by Saccharomyces cereviseae (SC) was used to evaluate cell cytotoxicity and anti-inflammatory potential of the plant extracts and fractions. Macrophages were treated with different concentrations (0.1; 1; 10 and 100 μg/mL) of the extracts/fractions for the inhibition of 5-lipoxygenase activity, nitric oxide (NO) and Tumor Necrosis Factor Alpha (TNF-α) production. No significant difference was observed on cell viability in the presence of extracts and fractions at tested concentration during the incubation period. Extracts and fractions of C. variegatum inhibited the 5-lipoxygenase activity, NO and TNF-α production by viable primary mouse macrophages in a concentration-dependent manner. The fractionation process increased anti-inflammatory activity. Among fractions, HEF2, HEF3, HEF5, EEF1, EEF3 and EEF5 exhibited the best anti-inflammatory potential. C. variegatum extracts and fractions exhibited a greater anti-inflammatory potential throughout the inhibition of pro-inflammatory mediators such as NO, 5-Lox and TNF-α.
Marie Ange Djeungoue Petga, Arnaud Fondjo Kouam, Rosine Désirée Chougouo Kengne, Borris Rosnay Galani Tietcheu, Josué Simo Louokdom, Claude Bérenger Ngantchouko Ngalemo and 2 more
Metabolism Open
Artesunate (ART) is a semi-synthetized molecule from Artemisinin, an active compound isolated from the medicinal plant Artemisia annua, widely used for the treatment of malaria. Previous studies reported that ART may exert a dual effect on the liver. Accordingly, this study investigated the potential protective action of ART against Acetaminophen (APAP) and Carbon tetrachloride (CCl4)-induced hepatotoxicity in primary mice hepatocytes, in comparison to that of flavonoid extracted from A. annua (FAA). In addition, the antioxidant properties of FAA were also assessed. The antioxidant activities of FAA and Ascorbic acid (ASC) (0.01–100 μg/mL) were assessed through inhibition of lipid peroxidation, reduction of ferric and phosphomolydenum, and hydroxyl and DPPH radicals scavenging assays. The hepatoprotective effects of FAA and ART (0.1–100 μg/mL) were evaluated against APAP (11 mM) or CCl4 (4 mM) induced oxidative damage in primary mouse hepatocytes. Biochemical parameters associated with hepatotoxicity assessed include cell viability, cell membrane integrity, cellular glutathione, and antioxidant enzyme activities. The obtained finding revealed FAA displayed a remarkable antioxidant activities as evidenced by the low IC50/EC50 values (3.85–19.32 μg/mL), comparable to that of ASC (3.26–18.04 μg/mL). When tested at 10 μg/mL, both FAA and ART significantly (p˂0.05) preserved cell viability, inhibited alanine aminotransferase leakage and lipid membrane peroxidation, and restored superoxide dismutase and catalase activities and glutathione content induced by APAP or CCl4 in a similar way as Silymarin. However, ART showed a significant (p˂0.05) cytotoxic effect on hepatocytes at 100 and 1000 μg/mL and did not confer obvious protection at 100 μg/mL. Overall, our data demonstrated that ART harms mice hepatocytes at high concentration while conferring relative protection against APAP and CCl4-hepatotoxicity at low concentration. In contrast, FAA effectively protects liver cells without cytotoxicity effect, event at 100 μg/mL. Accordingly, ART should be given to the patient only under a medical prescription.
Sylvain Pechangou Nsangou, Roukayatou Ndiandoukoue Ndam, Emmanuel Mfotie Njoya, Brice Enang, Frédéric Nico Njayou, Paul Fewou Moundipa
Investigational Medicinal Chemistry and Pharmacology
Background: Sida rhombifolia (L) is a medicinal plant from tropical regions belonging to the Malvaceae family and the plantea kingdom. It is known for its multiple pharmacological properties. The aim of this work was to evaluate the anti-amoebic, and anti-inflammatory potential of Sida rhombifolia aqueous and ethanolic leaf and stem extracts harvested in two localities of Cameroon (Yaoundé and Massangam in the Centre and West regions, respectively). Methods: The anti-amoebic activity was evaluated on a polyxenic culture of Entamoeba histolytica. A primary macrophage culture activated by Saccharomyces cereviseae (SC) was used to evaluate anti-inflammatory potential of the plant extracts. Macrophages were treated with different concentrations (1; 10; 100 and 500 μg/mL) of the extracts for the inhibition of nitric oxide (NO) production and 5-lipoxygenase activity. Methods: The anti-amoebic activity was evaluated on a polyxenic culture of Entamoeba histolytica. A primary macrophage culture activated by Saccharomyces cereviseae (SC) was used to evaluate the anti-inflammatory potential of the plant extracts. Macrophages were treated with different concentrations (1; 10; 100 and 500 μg/mL) of the extracts for the inhibition of nitric oxide (NO) production and 5-lipoxygenase activity. Results: No significant difference was found between the anti-amoebic activity of the ethanolic extract of Yaoundé (Centre region, IC50 = 7.71 μg/mL) and that of ethanolic leaf extract from Massagam (West region IC50 = 7.77 μg/mL) after 72 hours. Among the extracts, ethanolic leaf extracts exhibited the highest anti-amoebic activity after 72 hours of treatment. Metronidazole showed better activity (IC50 = 5.96 µg/mL) in the same periods of time. Phenolic compounds and flavonoid contents were higher in Yaoundé (Centre region) ethanolic leaf extract, proving that these extracts can prevent certain damages linked to a state of oxidative stress. The ethanolic extracts of the leaves significantly inhibited NO production and 5-lipoxygenase activity in macrophages (IC50 of 3.85 µg/mL; 3.99 µg/mL and 36.64 µg/mL; 73.22 µg/mL respectively). Conclusion: This preliminary study shows that the ethanolic extract of S. rhombifolia possesses better anti-amoebic properties and can act at the level of the intestinal mucosa in order to fight against the damage linked to the dysfunction of the inflammatory cells.
Olivia Sandra Magne Ghomsi, Regine Sandra Maafo, N.S. Pechangou, Flore Eliane Eyenga, Hippolyte Tene Mouafo, Kinglsey Agbor Etchu and 1 more
Research Square
Abstract The study aimed to investigate the impact of breed on the carcass, meat quality, and sensory properties of two pig breeds, the Bandjock Local Pig (BLP) and crossbred Duroc X Large White (DLW) pigs. The experiments involved dividing 24 eight-week-old weaners into two groups, each randomly assigned to six two-pig units. The animals received similar feeding and management, while the study lasted for 120 days. The study found that carcass weight and backfat thickness were greater in DLW in comparison to BLP (p<0.05). DLW demonstrated significantly higher values in fat content and cooking loss than BLP (p<0.05). Both BLP and DLW displayed similar levels of lightness, redness, and yellowness in the meat (p>0.05). Furthermore, BLP exhibited decreased pH levels at 45 minutes and 24 hours compared to DLW (p<0.05). Significant high scores in meat quality (loin, ham, and shoulder) were achieved by sensory panelists for BLP compared to DLW, respectively (p<0.05). However, other sensory traits did not differ between breeds. These results imply that carcass characteristics improved in DLW than BLP, but BLP had better sensory properties. This study provides fundamental data on the meat quality of BLP and DLW.
Sara Nathalie Edjenguèlè Béboy, Louise Marie Coûte-Chère Mbog, Yannick Sani Jignoua, Paulin Teko Keumedjio, Patrick Kevin Motto Feune, Paul Fewou Moundipa
Zenodo (CERN European Organization for Nuclear Research)
Erectile dysfunction is a major public health problem leading to harmful consequences for couples. Hence the need to find adequate treatments using medicinal plants such as <em>Pycnanthus angolensis</em>, a Cameroonian plant used to treat erectile dysfunction. The effects of aqueous extract of <em>Pycnanthus angolensis</em> wood were evaluated on male rat sexual behavior and nitric oxide release. Adult male <em>Wistar </em>rats were divided into 4 groups of 5 each that included a group receiving orally: distilled water (10 ml/Kg BW), plant extract treatment (43 or 86 or 172 mg/kg BW). Sexual behaviors were monitored on days 1, 4, 7, and 14 by pairing male rats to receptive females and nitric oxide levels were assessed in penile homogenate. At the end of the 14 days of treatment, rats were killed and sexual organs weighed. No significant effect was observed on sexual organs weights. When administered at a dose of 43 mg/Kg, body weight; the plant extract significantly increased (p<0.05) the sexual performance as well as the libido of male rats. Nitric oxide release was significantly increased (p<0.05) in that group of extract-treated rats, while compared to the control group. The study demonstrates that <em>Pycnanthus angolensis</em> is a medicinal plant which can enhance the sexual behaviors of male rat. Hence, it can be used for the management of erectile dysfunction, mainly at a dose of 43 mg/Kg, body weight.
Sara Nathalie Edjenguèlè Béboy, Louise Marie Coûte-Chère Mbog, Yannick Sani Jignoua, Paulin Teko Keumedjio, Patrick Kevin Motto Feune, Paul Fewou Moundipa
World Journal of Advanced Research and Reviews
Erectile dysfunction is a major public health problem leading to harmful consequences for couples. Hence the need to find adequate treatments using medicinal plants such as Pycnanthus angolensis, a Cameroonian plant used to treat erectile dysfunction. The effects of aqueous extract of Pycnanthus angolensis wood were evaluated on male rat sexual behavior and nitric oxide release. Adult male Wistar rats were divided into 4 groups of 5 each that included a group receiving orally: distilled water (10 ml/Kg BW), plant extract treatment (43 or 86 or 172 mg/kg BW). Sexual behaviors were monitored on days 1, 4, 7, and 14 by pairing male rats to receptive females and nitric oxide levels were assessed in penile homogenate. At the end of the 14 days of treatment, rats were killed and sexual organs weighed. No significant effect was observed on sexual organs weights. When administered at a dose of 43 mg/Kg, body weight; the plant extract significantly increased (p<0.05) the sexual performance as well as the libido of male rats. Nitric oxide release was significantly increased (p<0.05) in that group of extract-treated rats, while compared to the control group. The study demonstrates that Pycnanthus angolensis is a medicinal plant which can enhance the sexual behaviors of male rat. Hence, it can be used for the management of erectile dysfunction, mainly at a dose of 43 mg/Kg, body weight.
Paul V. Mboumwa, Modeste Wankeu‐Nya, Théodore Sala Béyemé, Zacharie Nde, Emma F. Bend, Frantz Ngalle Epoupa and 6 more
Open Journal of Epidemiology
Sexual dysfunction is a group of diseases, disorders or difficulties experienced by men or women during any stage of normal sexual activity. In Africa in general and Cameroon in particular, statistical data concerning the prevelance and the main causes of male sexual dysfunction are rare due to socio-cultural and religious burdens and sometimes self-medication. The objective of this work was to determine the prevalences, comorbidities and the risk factors of the main sexual dysfunction in some hospitals in city of Douala. Through a descriptive retrospective study carried out from Novembre 2019 to June 2021, sociodemographic parameter, reasons of consultation, risk factors and type of male sexual dysfunction (erectile dysfunction or erectile dysfunction (ED), ejaculation disorders (EjD), libido disorders (LD) and disorders of sexual activity with pain or painful sexual intercourse (PSI)) were collected in the medical files of patients who have made urological consultation between 2016 and 2020 at the Deido District hospital, Laquintinie Douala Hospital and Douala General hospital respectively. At the end of our data collection, out of a total of 24995 consultations, 2743 (10.98%) patients were suffering from at least one male sexual dysfunction. Moreover, sexual disorders were the 2nd reason of urological consultation (13.69%) after urinary disorders (33.85%). Among sexual disorders, erectile (76%) and ejaculatory (20%) disorders were the predominant pathologies recorded with the prevalences of 9.79 et 2.62% respectively, and were mostly represented in patients from [41 - 50] for erectile dysfunction, and [18 - 30] years old for ejaculative dysfunction. In addition, the number of patients with ejaculatory and erectile dysfunctions was more important in patients from [18 - 30] and [31 - 40] years old respectively. Among patients presenting sexual disorders, several risk factors or pathologies were associated with the dysfunction: benign prostatic hyperplasia and metabolic syndrome (in patients over 50 years old); psychosocial problems, infections, and alcohol (in patients under 50 years old). These findings could be useful in the elaboration of therapeutic strategies for the management of the Cameroonian population suffering from sexual dysfunctions.
Sylvain Nsangou Pechangou, Carine Matsingang Fondjou, Charifa Ngbetnkom Mandou, Sunil Kumar, Mfotie Njoya Emmanuel, Frédéric Nico Njayou and 2 more
American Journal of Plant Sciences
Amoebiasis, classified as the third intestinal parasitic infection, represents a public health problem in low-income countries where hygiene and sanitation conditions are poor. With the resurgence of resistant pathogenic strains as well as ancestral considerations in developing countries such as Cameroon, many people rely on medicinal plants to treat a plethora of diseases. This work aimed to highlight the anti-amoebic and anti-oxidant potential of Codiaeum variegatum extracts and fractions. The anti-amoebic potential of C. variegatum was assayed on the polyxenic culture of the clinical isolates of E. histolytica. Then, the anti-oxidant potential of the ethanolic/hydroethanolic extracts and fractions was evaluated through DPPH radical scavenging, iron reduction (FRAP), lipid peroxidation inhibitory potential and total antioxidant capacity tests followed by the determination of phenolic compound and flavonoid content. It was found that the fractionation process decreased the amoebicidal activities of C. variegatum leaf extracts. However hydroethanolic extract (CI50: 10.08 ± 0.42, 5.18 ± 0.09, 5.18 ± 0.09 μg/mL respectively after 24, 48 and 72 hours) was more active than ethanolic extract (CI50: 15.59 ± 6.17; 9.61 ± 2.37; 6.26 ± 3.22 μg/mL respectively after 24, 48 and 72 hours). Interestingly, the activities of hydroethanolic extract were significantly non-different compared to metronidazole CI50: 8.42 ± 0.44, 6.45 ± 0.22 and 3.42 ± 0.33 μg/mL, respectively after 24, 48 and 72 hours). Ethanolic extract and EF5 showed higher Phenolic compound contents and higher antioxidant activity than hydroethanolic extract and other fractions through DPPH radical scavenging power (EC50 = 311.50 ± 4.12 μg/mL) and total antioxidant capacity (44 ± 0.07 mgEAA/gF). However, these activities are significantly lower than those of ascorbic acid (EC50 = 31.20 ± 4.39 μg/mL, and 61.34 ± 4.42 μg/mL respectively). This low antioxidant activity was confirmed by poor phenolic and flavonoid compounds contents found in the extracts and fractions. The present result brings a new approach to the ethnopharmacological uses of C. variegatum against dysentery in cases associated with Amoebiasis in Cameroun.
Paulin Teko Keumedjio, Sara Nathalie Edjenguèlè Béboy, Paul Fewou Moundipa
Investigational Medicinal Chemistry and Pharmacology
Background: Male infertility and erectile dysfunction are the main conditions associated with male reproductive function disorders. Testosterone is the main hormone that regulates male reproductive function, while nitric oxide is a potent vasodilator involved in the erectile process. Methods: This study was conducted to evaluate in vitro the potential of the aqueous extract of six Cameroonian medicinal plants traditionally used for male reproductive function: Palisota ambigua, Terminalia superba, Rauvolfia macrophylla, Pycnanthus angolensis, Pausynistalia yohimbe, and Shumanniophyton magnificum. Results: Their effect on testosterone and nitric oxide production was evaluated using rat interstitial and macrophage cells, respectively. Then, the antioxidant properties, flavonoids, and total phenolic content were assessed. The phytochemical screening was also performed. Conclusion: Each plant extract significantly increased (p<0.05) testosterone production. At 100 µg/mL, the extract of Schumanniophyton magnificum showed the highest level (3.730 ng/mL). Each plant extract significantly increased (p<0.05) the production of nitric oxide. The aqueous extract of Rauvolfia macrophylla showed the highest level of nitric oxide with an EC50 = 8.554 µg/mL. For antioxidant activities, Terminalia superba showed the highest antiradical activity (SC50 = 4.796 µg/mL), the highest reducing power (OD = 2.235 at 700 nm), and the highest total antioxidant capacity (276.035 mgEAA/g of plant extract) and while Pausynistalia yohimbe, showed the highest inhibition on lipid peroxidation (15.170 µg/mL). Terminalia superba also showed the highest flavonoid (13.419 mgEQ/g) and total phenolic (300.813 mgEGA/g) content. The phytochemical screening of the plant extracts showed many active secondary metabolites such as alkaloids, phenols, flavonoids, saponins, and glycosides. All the extracts showed androgenic effects and antioxidant activities without significant cytotoxicity, thus supporting the use of these medicinal plants by traditional healers for managing male infertility.
Arnaud Fondjo Kouam, Noé Auguste Nseké Ngoumé, Armelle Gaelle Kwesseu Fepa, Zerubabel Wainfen, Eléonore Ngounou, Borris Rosnay Galani Tietcheu and 4 more
Egyptian Liver Journal
Abstract Background Malaria is an endemic mosquito-borne disease in sub-Saharan regions, including Cameroon. Due to the obligatory hepatic stage of its pathogenic agents, malaria can induce liver damage if not properly treated. Hence, we assessed the impact of malaria infection on liver transaminases among febrile patients consulting at the Deido District Hospital, Douala-Cameroon, in regard to their attitude towards the practice of preventive measures, treatment, and management of malaria. Methods Over 10 weeks, 150 febrile patients and 28 healthy individuals serving as the control group were enrolled and their blood samples screened for Plasmodium species by Giemsa Staining and liver injury evaluated by measuring the serum level of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities. The socio-demographic characteristics of participants and their attitude towards the practice of preventive measures, treatment, and management of malaria were collected using a structured- questionnaire. Results Among tested febrile patients, 113 (75%) were malaria-positive. Females were more affected (65.5%) than males; the most affected age group were adults between 30-60 years (55.8%). A significant association (p˂0.05; relative risk [RR] = 1.424 or p˂0.05; RR = 1.947) was found between malaria infection and non-use of mosquito nets or insecticides, respectively. The serum level of ALT and AST activities in malaria-positive were significantly ( p <0.05) increased, compared to healthy or malaria-negative individuals. Furthermore, transaminase activity was significantly ( p <0.05) elevated in non-practitioners of preventive measures; and in patients who engaged in auto-medication or traditional medication, compared to those who sought treatment from health centers. Conclusion Our findings demonstrated that non-practice of preventive measures, improper treatment and management of malaria infection can lead to an abnormal increase in serum level of transaminases which may reflect liver injury.
Brice Enang, Sylvain Nsangou Pechangou, Frédéric Nico Njayou, Marie Louise Medoua, Paul Fewou Moundipa
Zenodo (CERN European Organization for Nuclear Research)
<strong>Background</strong>: Wild edible fruits are good source of phenolic compounds such as anthocyanins. Those compounds are known for their anti-inflammatory potential. They interact with many mediators of the physiopathological pathway such as NF-kB which is at a central position in the inflammatory response in macrophages. This study aimed to determine the anti-inflammatory and antioxidant potential of ten wild edible fruits aqueous extracts. <strong>Methods: </strong>The antioxidant potential was evaluate through the DPPH, ABTS and OH radical scavenging activity; the ferric reducing agent power and the total antioxidant capacity assessment. Also, the total phenolic and flavonoids, anthocyanins compounds and vitamin C content were assayed. For the anti-inflammatory activity, a primary macrophage culture was used. Inflammatory mediators such as nitric oxide (NO), alkaline phosphatase, NADPH oxidase and 5-lipoxigenase activity was assayed. <strong>Results: </strong><em>Alchornea cordifolia</em> and <em>Pentaclethra macrophylla </em>extracts showed the greatest antioxidant activity respectively (Antiradical power (AP)=5.82 mol of DPPH/mg of extract and AP=5.05 mol of DPPH/mg of extract for DPPH scavenging assay); (IC<sub>50</sub>=1.62µg/ml and IC<sub>50</sub>=1.60µg/ml for ABTS radical scavenging assay); (IC<sub>50</sub>=32.67µg/ml and IC<sub>50</sub>=70.01µg/ml for OH radical scavenging assay) and (EC<sub>50</sub>=54.06µg/ml and EC<sub>50</sub>=17.46µg/ml for ferric reducing antioxidant power) with a non-significant difference with the reference compound. For the anti-inflammatory activity, firstly it has been observed that <em>Alchornea cordifolia’s </em>extract exhibits the greatest potential against NADPH oxidase activity inhibition (IC<sub>50</sub>=36.20µg/ml); alkaline phosphatase activation (EC<sub>50</sub>=0.27µg/ml) with non-significant difference with the reference compound. Secondly, <em>Pentaclethra macrophylla’s</em> extract demonstrated a high ability to inhibit NO production (IC<sub>50</sub>=5.79µg/ml) and 5-lipoxigenase (IC<sub>50</sub>=1.41µg/ml). <strong>Conclusion: </strong>From the results obtained the assessed wild fruit extracts appears to be good sources for anti-inflammatory and antioxidant bioactive molecules. They could be beneficial for the research of new modulators for the management of inflammatory disorders.
Brice Enang, Sylvain Nsangou Pechangou, Frédéric Nico Njayou, Marie Louise Medoua, Paul Fewou Moundipa
World Journal of Advanced Research and Reviews
Background: Wild edible fruits are good source of phenolic compounds such as anthocyanins. Those compounds are known for their anti-inflammatory potential. They interact with many mediators of the physiopathological pathway such as NF-kB which is at a central position in the inflammatory response in macrophages. This study aimed to determine the anti-inflammatory and antioxidant potential of ten wild edible fruits aqueous extracts. Methods: The antioxidant potential was evaluate through the DPPH, ABTS and OH radical scavenging activity; the ferric reducing agent power and the total antioxidant capacity assessment. Also, the total phenolic and flavonoids, anthocyanins compounds and vitamin C content were assayed. For the anti-inflammatory activity, a primary macrophage culture was used. Inflammatory mediators such as nitric oxide (NO), alkaline phosphatase, NADPH oxidase and 5-lipoxigenase activity was assayed. Results: Alchornea cordifolia and Pentaclethra macrophylla extracts showed the greatest antioxidant activity respectively (Antiradical power (AP)=5.82 mol of DPPH/mg of extract and AP=5.05 mol of DPPH/mg of extract for DPPH scavenging assay); (IC50=1.62µg/ml and IC50=1.60µg/ml for ABTS radical scavenging assay); (IC50=32.67µg/ml and IC50=70.01µg/ml for OH radical scavenging assay) and (EC50=54.06µg/ml and EC50=17.46µg/ml for ferric reducing antioxidant power) with a non-significant difference with the reference compound. For the anti-inflammatory activity, firstly it has been observed that Alchornea cordifolia’s extract exhibits the greatest potential against NADPH oxidase activity inhibition (IC50=36.20µg/ml); alkaline phosphatase activation (EC50=0.27µg/ml) with non-significant difference with the reference compound. Secondly, Pentaclethra macrophylla’s extract demonstrated a high ability to inhibit NO production (IC50=5.79µg/ml) and 5-lipoxigenase (IC50=1.41µg/ml). Conclusion: From the results obtained the assessed wild fruit extracts appears to be good sources for anti-inflammatory and antioxidant bioactive molecules. They could be beneficial for the research of new modulators for the management of inflammatory disorders.
Youchahou Ndam Njankouo, Maximilienne Ascension Nyegue, Ibrahim Njingou, Paul Fewou Moundipa, Pauline Mounjouenpou
Dose-Response
The present work aimed to evaluate acute and sub-acute toxicity of cortex cassava crude extract containing scopoletin and cyanide. The limit test method of OECD at 2000 mg/kg was used to determine the LD 50 of the crude extract in female Wistar rats, and the sub-acute toxicity was conducted in broilers by incorporating their feed with the cortex powder at 2 mg, 4 mg and 8 mg of powder per 100 g of standard food, corresponding to MIC, 2MIC and 4MIC: those concentrations, respectively, corresponded to .07 μg, .14 μg and .28 μg of scopoletin and 2.8 μg, 5.6 μg and 11.2 μg of cyanide. An oral LD 50 greater than 2000 mg/kg was obtained, and the effective antifungal dose was non-toxic. No changes were observed in the rate of biochemical parameters and relative weight of the liver, kidneys and brain of broilers. Any damages were not observed after the histopathological exams of these organs regardless the diet considered, compared to the control group. All results ranging from efficacy and safety of cassava cortex extract containing scopoletin and cyanide allowed us to consider it as biopesticide for staple food preservation against post-harvest losses.
Olivia Sandra Magne Ghomsi, Paddy Daniel Wuld Mveng, Valentine Petentsebenkwange Nchinda, Kingsley Agbor Etchu, Charles Félix Bilong Bilong, Paul Fewou Moundipa
International Journal of Biological and Chemical Sciences
A socio-economic characterization of the indigenous pig farming systems, performance analysis, and constraints were carried out in three agro-ecological areas of Cameroon such as Sudano-Sahelian (SSA), Western highland (WHA) and Humid forest with bimodal rainfall Areas (HBA). A questionnaire was administered to 157 farmers. The data were analyzed using the descriptive statistics procedure. The results showed that pig farming was mainly practised by men over forty year old (79.1%), with a low level of technical supervision and having reached the level of primary education (44.6%). The production systems in HBA and SSA are mostly extensive whereas in WHA these systems were mostly semi-intensive. The piggeries were made with wooden pens (61.1%). The farms were more prone to feed shortages in the SSA and WHA. The animals were mostly fed once (45.8%) or twice (38.9%) a day. Animals were largely unvaccinated (40.8%) and not dewormed (59.9%). The SSA farming system was the least efficient in terms of gross added value per sow per year (GVA /sow/year = 398 USD) while the WHA and HBA (GVA/ sow/year in the WHA = 1305 USD and GVA /sow/year in the HBA= 1210 USD). This characterization is important for future improvements in livestock management, especially with the indigenous pig farming system in Cameroon.
Sylvain Nsangou Pechangou, Brice Enang, Vigny Sayal Ngohoba, Emmanuel Mfotie Njoya, Frédéric Nico Njayou, Paul Fewou Moundipa
Journal of Exploratory Research in Pharmacology
Codiaeum variegatum (C. variegatum), which is commonly known as garden croton, is a medicinal plant used for the treatment of amoebiasis in Cameroon and some Asian countries. The present study aims to evaluate the antioxidant and anti-inflammatory activities of the stem crude extracts of C. variegatum.
Anirban Mandal, Banasri Hazra, Vijay Kumar Prajapati, Paul Fewou Moundipa
Frontiers in Pharmacology
Editorial on the Research Topic Plant products for antiviral therapeuticsDiseases caused by microbial infections continue to pose major public health challenges despite the enormous modernization of therapeutic strategies to alleviate human health disorders.From time to time, numerous such afflictions due to HIV, hepatitis B & C, herpes simplex, dengue, Ebola, and influenza viruses raised universal concern, underscored by the recent COVID-19 pandemic caused by SARS-CoV-2 (Mandal et al., 2021).Although some antiviral drugs or cocktails of drugs are available to combat these viruses, nevertheless, most of these medications showed side effects and other drawbacks like low antiviral activity, genotype-dependent efficacy, and the emergence of drug-resistant mutants.Therefore, the development of more suitable therapeutics in this field is certainly a need of the hour.Historically, medicinal herbs and natural products are the mainstay of general healthcare systems around the globe and are considered an integral part of the cultural heritage of mankind.Truly, the plant kingdom is an invaluable repository of countless phytochemicals with distinctive molecular frameworks, which provide clues on the core structures as templates for the development of novel drug molecules.Thus, quite a number of such traditional medicinal plants yielded a variety of drugs enlisted in the modern pharmacopeia.In fact, a substantial number of FDA-approved drugs are based on natural products or their derivatives (Atanasov et al., 2021).Time-honoured herbal prescriptions practised worldwide, such as Traditional Chinese Medicines (TCM), Indian Ayurvedic and Middle-eastern Unani systems, and various regional folkloric treatments in Africa and elsewhere continue to fulfil basic healthcare requirements in developing countries (Mandal et al., 2020).As for the Western people, a resurgence in popularity of natural products for health promotion have been observed in the past few decades (World Health Organization, 2019).In fact, many medicinal plant extracts are now prescribed for the treatment of chronic ailments.Therefore, a strategic approach to combat viral infections would be to explore the
Emma F. Bend, Brice L. Koloko, Sylvin Benjamin Ateba, Modeste Wankeu‐Nya, Marie I. Ngaha Njila, Zacharie Nde and 6 more
Pharmacology & Pharmacy
In recent years, the rate of infertility has not stopped increasing in the world. The aim of the present study was to evaluate the effects of the aqueous extract of Schumanniophyton magnificum (Rubiaceae) on cyclicity, ovulation and gestation in mature rats. Methods: After a qualitative phytochemical analysis of these aqueous extracts, the experimental studies carried out were based on the evaluation of the pro-fertility effects of this extract in mature rats. For this purpose, 35 rats were used for the estrous cyclicity test and treated for 21 days at the end of which vaginal smears were taken and the duration, as well as the frequency of the appearance of the phases of the cycle, were evaluated. The ovulation test was performed on 80 female rats, which were divided into two groups of 40 animals and treated respectively in the morning and evening with distilled water, β-oestradiol or plant extract at doses of 200, 400 and 800 mg/kg. At the end of estrus, the rats were sacrificed, the ovaries were removed and weighed, the hemorrhagic points counted and the blood samples were taken for hormonal studies. The last phase of the study consisted in evaluating the effects of these plant extracts on the evolution of gestation. Thus, 42 mature rats were treated during the periods from the 1st to the 10th day (1st stage), and from the 11th to the 17th day (2nd stage). At the end of these two phases, a laparotomy was performed and the number of implantation sites and corpus luteum was counted. And finally, at parturition, from the 18th to the 22nd day (3rd stage), the number of living pups was performed and the gestational parameters were calculated. Results: Administration at the beginning of prœstrus allowed a significant increase (p S. magnificum extract. On the other hand, a significant decrease in progesterone levels (p S. magnificum at doses of 200, 800 mg/kg (p S. magnificum when compared to the control (23 ± 0.16 d). Conclusion: It appears from all these investigations that the aqueous extract of S. magnificum promotes fertility in the rat but represents a danger for the good development of gestation. All these results obtained would be closely related to the presence of certain chemical compounds contained in these various extracts; which would justify their use in traditional medicine for the treatment of certain cases of female infertility in Cameroon.
Raoul Kenfack‐Momo, Sébastien Kenmoe, Guy Roussel Takuissu, Jean Thierry Ebogo‐Belobo, Cyprien Kengne-Ndé, Donatien Serge Mbaga and 16 more
PLoS ONE
INTRODUCTION: Due to their common routes of transmission, human immunodeficiency virus (HIV) coinfection with hepatitis B virus (HBV) and/or hepatitis C virus (HCV) has become a major public health problem worldwide, particularly in Africa, where these viruses are endemic. Few systematic reviews report the epidemiological data of HBV and/or HCV coinfection with HIV in Africa, and none provided data on the case fatality rate (CFR) associated with this coinfection. This study was conducted to investigate the prevalence and case fatality rate of HBV and/or HCV infections among people living with human immunodeficiency virus (PLHIV) in Africa. METHODS: We conducted a systematic review of published articles in PubMed, Web of Science, African Journal Online, and African Index Medicus up to January 2022. Manual searches of references from retrieved articles and grey literature were also performed. The meta-analysis was performed using a random-effects model. Sources of heterogeneity were investigated using subgroup analysis, while funnel plots and Egger tests were performed to assess publication bias. RESULTS: Of the 4388 articles retrieved from the databases, 314 studies met all the inclusion criteria. The overall HBV case fatality rate estimate was 4.4% (95% CI; 0.7-10.3). The overall seroprevalences of HBV infection, HCV infection, and HBV/HCV coinfection in PLHIV were 10.5% [95% CI = 9.6-11.3], 5.4% [95% CI = 4.6-6.2], and 0.7% [95% CI = 0.3-1.0], respectively. The pooled seroprevalences of current HBsAg, current HBeAg, and acute HBV infection among PLHIV were 10.7% [95% CI = 9.8-11.6], 7.0% [95% CI = 4.7-9.7], and 3.6% [95% CI = 0.0-11.0], respectively. Based on HBV-DNA and HCV-RNA detection, the seroprevalences of HBV and HCV infection in PLHIV were 17.1% [95% CI = 11.5-23.7] and 2.5% [95% CI = 0.9-4.6], respectively. Subgroup analysis showed substantial heterogeneity. CONCLUSIONS: In Africa, the prevalence of hepatotropic viruses, particularly HBV and HCV, is high in PLHIV, which increases the case fatality rate. African public health programs should emphasize the need to apply and comply with WHO guidelines on viral hepatitis screening and treatment in HIV-coinfected patients. REVIEW REGISTRATION: PROSPERO, CRD42021237795.
Arnaud Fondjo Kouam, Micheline Masso, Ferdinand Elombo Kouoh, Rodrigue Fifen, Ibrahim Njingou, Angèle N. Tchana and 2 more
Heliyon
People living in developing countries are exposed to hepato-renal injuries induced by heavy metals like lead (Pb), cadmium (Cd), and mercury (Hg) since drinking water supplied is often polluted with a high concentration of those metals. Accordingly, it is necessary to search for antidotes against heavy metals poisoning. Hence, medicinal plants bearing anti-hepatotoxic properties represent a credible option; and such plant is Khaya grandifoliola . However, there is a paucity of knowledge regarding its protective effect on heavy metals-induced hepato-renal toxicity. Thus, this study was designed to assess the protective effect of the hydro-ethanolic stem bark extract of K. grandifoliola (HKG) against hepato-renal injuries induced by chronic consumption of drinking water containing high contents of Pb, Cd, and Hg; in addition to the investigation of the chemical antioxidant properties of HKG. For the antioxidant assays, HKG was tested as a potential inhibitor of lipid peroxidation, reducer of ferric and phosphomolybdenum, and scavenger of hydroxyl and 2,2- Diphenyl-Picryl-Hydrazyl radicals. Its protective effects were evaluated by daily co-treating rats with heavy metals solution (10 mL/kg b.w) containing 0.9, 0.58, and 1.13 ppm respectively for Pb, Cd and Hg and HKG (25 or 100 mg/kg b.w) for five consecutive months; and biochemical parameters associated to liver and kidneys functions, oxidative stress and metals bioaccumulation were assessed. HKG displayed a strong antioxidant capacity (IC50/EC50 range 3.95–17.17 μg/mL) correlated to its polyphenols content and comparable to that of Ascorbic acid. Serum levels of alkaline phosphatase, alanine/aspartate aminotransferase, and creatinine; renal and hepatic content of Cd and Pb, malondialdehyde and glutathione, activities of superoxide dismutase and catalase showed the protective effect of HKG, further evidenced by histopathological analysis. Taking together, these results demonstrated that HKG alleviates heavy metals-induced hepato-renal injuries in rats by reducing oxidative stress and metals-bioaccumulation.
Brice Ayissi Owona, Frédéric Nico Njayou, Pierre Mkounga, Paul Fewou Moundipa
In Silico Pharmacology
Frédy Brice Simo Nemg, Saikat De, Supriya Suman Keshry, Prabhudutta Mamidi, Frédéric Nico Njayou, Maurice Demanou and 2 more
Journal of Ethnopharmacology
Fredy Brice Nemg Simo, Saikat De, Supriya Suman Keshry, Prabhudutta Mamidi, Frédéric Nico Njayou, Maurice Demanou and 2 more
SSRN Electronic Journal
Emmanuel Mfotie Njoya, Paul Fewou Moundipa, Timo H. J. Niedermeyer
Journal of Ethnopharmacology
Ashok Agarwal, Dulce E. Alarcón‐Yaquetto, Roodabeh Bahramsoltani, Saptaparna Chakraborty, Rima Dada, Anandan Das and 25 more
Elsevier eBooks
Corinne Raïssa Ngnameko, Jean Jacques Noubiap, Freddy Brice Simo Nemg, Mohamadou Abdou Galdima, Guy Roussel Takuissu-Nguemto, Sophie Ngo-Boumso and 3 more
medRxiv
Abstract Objectives Although global epidemiology of Helicobacter pylori (HP) infection is well characterized, country-specific figure is more accurate for context-specific tailored interventions. The aim was to determine the prevalence, factors associated with infection, antibiotic resistance profile, and genotypes of HP in Cameroon. Design A systematic review with meta-analysis. Participants People living in Cameroon regardless of their clinical profile. Data sources and synthesis Observational studies published in PubMed, EMBASE, African Index Medicus, African Journals Online, and Health Sciences and Diseases up to October 12 th , 2020. Study selection, data extraction, and methodological quality assessment were done by two independent authors. Random-effect meta-analysis served to pool prevalence data. Results Fifteen studies were included. None investigated the genotypes of HP. Among symptomatic patients, the most common used test, urea breath test on gastric biopsy, yielded a prevalence 57.8% (95% confidence interval (CI): 34.3-79.5) of HP infection. This prevalence significantly varied between 47.0% (95%CI: 43.0-51.0) for antigen test in stool samples and 71.2% (95%CI: 59.1-81.9) for Giemsa on gastric biopsy; p = 0.0006. One study in asymptomatic children reported the prevalence of 52.3% (95%CI: 44.9-59.6) using antigen test for stool samples. Among the six studies investigating factors associated with HP infection, one performed a multivariable model and identified being student as protective factor compared to being employed (Odds ratio: 0.09; 95%CI: 0.02–0.49). For antibiotics used for first line treatment, HP was resistant to amoxicillin (85.6-97.1%), metronidazole (93.2-97.9%), and clarithromycin (13.6-44.7%) as reported in two studies. Limitation Data were from six of the ten regions of Cameroon, hindering the generalizability of the findings to the country. Conclusion This study depicted a high prevalence of HP infection and a worrying resistance profile to first-line antibiotics. When waiting for well-conducted studies, updated guidelines are needed for clinical practice for first-line antibiotic treatment. Registration PROSPERO, CRD42020220084. Strengths and limitations of this study Not all the 10 regions of the country were represented in this study, hindering the generalizability of the findings. We were not able to substantially investigate sources of heterogeneity in the prevalence of Helicobacter pylori infection due to scarcity of data. Evidence investigating factors associated with Helicobacter pylori infection are weak and there was scarcity on data exploring antibiotic resistance profile of Helicobacter pylori . This study is the first to provide an estimate of the epidemiology and resistance profile of Helicobacter pylori in Cameroon.
Chinyerum S. Opuwari, Paul Fewou Moundipa
Elsevier eBooks
Borris Rosnay Galani Tietcheu, Vincent Brice Ayissi Owona, Roméo Joel Guemmogne Temdie, Karoline Metzger, Marie Atsama Amougou, Pascal Dieudonné Djamen Chuisseu and 5 more
In Silico Pharmacology
Ella Fils Armand, Manjula Shantaram, Simon Ngamli Fewou, Frédéric Nico Njayou, Sayali Chandrashekhar Deolankar, Prashant Kumar Modi and 1 more
International Journal of Phytomedicine
Alzheimer’s disease (AD) belongs to the class of neurodegenerative disorder and is biochemically characterized by amyloid-β (Aβ) plaques deposition, accumulation of neurofibrillary tangles (NFTs) accumulation and ultimately neuronal loss. Even though, the progress made in developing efficient AD therapy, there is no effective drug capable to stop and/or slow down AD progression. In the current article, we investigated the neuroprotective effect of Khaya grandifololia crude extract and fraction 2 against Aβ 42 -induced cytotoxicity and hyperphosphorylation of tau protein in differentiated neuronal cells (IMR32). Reactive oxygen species production, apoptosis and mitochondrial dynamics and function, synaptic protein, and tau phosphorylation were evaluated using fluorescence microscopy and immunoblotting. Cell viability was assessed using the MTT assay. Findings revealed that exposure of differentiated IMR32 cells to Aβ 42 alone induced the impairment of mitochondrial dynamics, decrease synaptic protein expression and increase hyperphosphorylation of tau protein (phospho tau181). In contrast, the presence of crude extract and KGf2 significantly inhibited the cleavage of Caspase-3 activation. In addition, the levels of synaptic proteins (Symptosomal associated protein 25 and Synaptosin) and superoxide dismutase were restored upon treatment with crude extract and fraction 2. Hyperphosphorylation of tau protein (Thr181) and ERK (Thr202/Tyr205) activities were also significantly reduced after treatment with crude extract and fraction 2. Our findings suggest that KG extract is a potential source for candidate drug against AD and may contribute to the development of efficient therapeutic strategy against AD.
Arnauld Efon-Ekangouo, Hugues C. Nana-Djeunga, Guilhem Sempéré, Joseph Kamgno, Flobert Njiokou, Paul Fewou Moundipa and 1 more
bioRxiv (Cold Spring Harbor Laboratory)
Abstract Background Vector control using larvicides is the main alternative strategy to address limits of preventive chemotherapy using ivermectin to fight onchocerciasis. However, it remains substantially limited by implementation difficulties, ecological concerns and resistance of vector populations. Therefore, efficient and environmentally safe alternative control strategies are still needed. This study explores the role of blackfly bacterial communities both on vector competence and refractoriness to O. volvulus infection in order to determine their potential as a novel vector control-based approach to fight onchocerciasis. Principal findings A total of 1,270 blackflies were dissected and the infection rate was 10.1%, indicative of ongoing transmission of onchocerciasis in the surveyed communities. Sequencing process revealed 19 phyla and 210 genera, highlighting the diversity of gut blackflies bacterial communities. Wolbachia was the predominant genus with 70% of relative abundance of blackflies gut bacterial communities. Serratia sp and Acidomonas genera were significantly abundant among infected blackflies (p=0.043 and p=0.027, respectively), whereas other genera as Brevibacterium were associated with the absence of infection (p=0.008). Conclusion/Significance This study revealed that blackfly native bacteria are potentially involved in infection by O. volvulus , either by facilitating or preventing the parasite infestation of the vector. These bacteria represent an interesting potential as a biological target for a novel approach of vector control to fight onchocerciasis. Author summary Studies of arthropods involved in vector-borne diseases (tsetse flies, mosquitoes, and drosophila) demonstrated the importance of their native bacteria either to ease infection and transmission of human pathogenic microorganisms including parasites or on the contrary to induce host protective effects against these parasites. Indeed, some native bacteria of arthropod vectors are now recognized to be associated either with the resistance of their hosts to parasitic infections, or the reduction of their host’s viability in case of the parasite infestation, thus highlighting the potential of such bacteria to be used as biological tool for vector control strategies. However, such bacteria have never been described on blackfly, an arthropod transmitting Onchocerca volvulus , which is the parasite responsible of onchocerciasis commonly known as river blindness. This study aimed to fill this gap by investigating the bacterial diversity of blackfly bacteriome and describing the possible role of bacteria communities in susceptibility/resistance features of the blackflies to O. volvulus infection, and therefore their potential as biological targets or tool for vector control. The screening of these blackflies’ native bacteria during this study, highlighted some bacteria genera of interest with significant association either with the absence of O. volvulus in blackfly or with vector infection.
Faustin Pascal Tsagué Manfo, Sharon Asukia Mboe, Edouard Akono Nantia, Ferdinand Ngoula, Phélix Bruno Téléfo, Paul Fewou Moundipa and 1 more
Journal of Toxicology
Agro pesticides are increasingly used worldwide to increase crop production. However, health hazards resulting from human exposure to these chemicals, especially from agricultural areas of developing countries have been a growing concern. The objective of this study was to evaluate the impact of occupational exposure to agro pesticides on the health of farmers in the Buea subdivision, which is one of the major agrarian areas in Cameroon. The study was transversal and involved 90 participants including 58 farmers using pesticides and a reference population of 32 men not involved in occupational use of agro pesticides. The participants were interviewed on agro pesticide use and their health status. Thereafter, blood samples were collected from the participants and used for the assessment of biochemical markers of the liver (alanine aminotransferase and aspartate aminotransferase) and the kidney (creatinine and uric acid) function. Results revealed that farmers frequently used insecticides, fungicides, and herbicides in their farming activities. Farmers reported several acute health symptoms related to pesticides use with the common ones being skin rash, eye irritation, and face burn. When compared to the reference population, the farmers showed significantly elevated (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mrow><mml:mi>p</mml:mi><mml:mo><</mml:mo><mml:mn>0.01</mml:mn></mml:mrow></mml:math>) alanine aminotransferase activity. However, other parameters investigated were not affected significantly. These results suggested that farmers were exposed to 3 different classes of agro pesticides, which induced eye and skin affections. Pesticides exposure resulted in alterations of the liver function hence the increased serum alanine aminotransferase activity. Therefore, there is a need to sensitize the farmers on toxicity and liver alteration potential of agro pesticides and the importance of appropriate protective equipment that may minimize exposure.
Borris Rosnay Galani Tietcheu, Brice Ayissi Owona, Dieudonné Pascal Djamen Chuisseu, Esaïe Machewere, Claude Beranger Ngalemo Ngantchouko, Paul Fewou Moundipa
BioMed Research International
Background and Objectives . Leptadenia hastata is a liana from the family of Asclepiadaceae used in tropical Africa to treat diabetes mellitus. In this study, we investigated its hepatoprotective mechanisms on acetaminophen‐ (APAP‐) induced toxicity through in vivo and in silico approaches. Materials and Methods . Various aqueous extracts were prepared from this plant and preadministered per os to albino mice 3 h before APAP administration, once daily for one week. Animals from the normal group were given only distilled water while those from negative control received only APAP 250 mg/kg. After treatment, mice were sacrificed, the liver was collected for histopathology analysis, and different biochemical markers (alanine aminotransferase (ALT), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), malondialdehyde (MDA), and tumor necrosis factor‐alpha (TNF α )) were measured. The content of the active extract was analyzed by HPLC/UV. Molecular docking was conducted using iGEMDOCK software, and the drug‐likeness and pharmacokinetic profiles were evaluated using Swiss ADME. Results . APAP administration significantly increased ( p < 0.001) ALT in liver homogenates when compared to normal controls whereas the stem decoction at 250 mg/kg significantly ( p < 0.001) reduced this activity to a normal value comparable to silymarin 50 mg/kg which is better than leaf and root extracts. Moreover, the stem decoction also significantly reduced the MDA levels ( p < 0.05) and increased those of GSH, SOD, and CAT ( p < 0.001) at doses of 250 and 500 mg/kg compared to the negative control. A significant ( p < 0.001) decrease of TNF α levels and leukocyte infiltration was observed following treatment with this extract. The HPLC/UV analysis of the decoction revealed the presence of dihydroxycoumarin, quinine, and scopoletin with the following retention times: 2.6, 5.1, and 7.01 min, respectively. In silico studies showed that quinine and dihydroxycoumarin had great potentials to be orally administered drugs and possessed strong binding affinities with TNF α , TNF receptor, cyclooxygenase‐2, iNOS, cytochrome P450 2E1, and GSH reductase. Conclusion . Based on these results, L. hastata could be considered a source of promising hepatoprotective compounds with antioxidant and anti‐inflammatory properties.
Arnaud Fondjo Kouam, Brice Ayissi Owona, Rodrigue Fifen, Frédéric Nico Njayou, Paul Fewou Moundipa
Heliyon
Entada africana is used in non-conventional medicine for the management of liver ailments. A fraction, designated EaF10 (methylene chloride/methanol 90:10, v/v) with promising hepatoprotective activity has been isolated. Since the mechanisms underlying EaF10 hepatoprotective action remain unknown, this study was undertaken to investigate the anti-hepatotoxic mechanism of the fraction against carbon tetrachloride (CCl 4 )-induced hepatotoxicity and its antioxidant properties. Antioxidant activities of EaF10 were assessed through four chemical antioxidant assays and its anti-hepatotoxic effect evaluated in vivo and in vitro by post-treatment (25 or 100 mg/Kg) or co-treatment (6.25–100 μg/mL) in CCl 4 -intoxicated mice and normal human liver cells line L-02 hepatocytes respectively; and biochemical and molecular parameters assessed respectively by spectrophotometry, and by quantitative real-time polymerase chain reaction and western blot analysis. EaF10 exhibited strong antioxidant activities correlated with its polyphenol content. Serum levels of alanine/aspartate aminotransferase (AST/ALT) and nitrite oxide, liver contents of glutathione (GSH) protein carbonylation and malondialdehyde (MDA), liver activities of catalase (CAT), glutathione-S-transferase (GST) and superoxide dismutase (SOD) and cell viability showed the anti-hepatotoxic effect of EaF10, supported by histopathological observations. The fraction decreased the protein level of Cytochrome P450 2E1 (CYP2E1) and Kelch-like ECH-associated protein-1 (Keap-1), induced nuclear translocation of Nuclear factor-erythroid 2-related factor-2 (Nrf2) coupled to an increase of the mRNA levels of CAT, SOD1 and GST in CCl 4 -intoxicated L-02 hepatocytes. These findings evidenced that the studied plant fraction possesses a strong antioxidant capacity and prevents CCl 4 -induced hepatotoxicity, likely through inhibition of CYP2E1 and activation of the Nrf2 signaling pathway.
Borris Rosnay Galani Tietcheu, Danielle W. Mapouokam, Fredy Brice Nemg Simo, Hassimi Mohamadou, Pascal Dieudonné Djamen Chuisseu, Nicolas Yanou Njintang and 1 more
Journal of Medical Virology
This study aimed at evaluating the seroprevalence of dengue among malarious patients consulting at the Ngaoundere Regional Hospital. During 2 months and a half, 174 participants were recruited and their blood samples were screened for Plasmodium spp and then for Dengue virus (DENV) infection using rapid diagnostic tests. Also, hematological asparameters were measured using a hematology autoanalyzer. Among patients tested, 134 (77.01%) were malaria-positive, and 12/134 (8.95%) were coinfected. In this population, 8/12 (66.67%) were only anti-DENV IgM-positive, 3/12 (25%) were both NS1 and anti-DENV IgM positive, and 1/12 (8.33%) were anti-DENV IgG-positive. Furthermore, women were more affected (58.3%) than men (41.7%). The most affected age groups were young people aged less than or equal to 15 years (33.3%) and adults aged between 30 and 45 years (33.3%). A significant association (p < .05; odds ratio [OR] = 5.16) was found between the age range (30-45) and dengue-malaria coinfection. Similarly, we noted a significant association between the coinfection, and joint pain (p < .05; OR = 6.15), fatigue (p < .01; OR = 5.74), and chills (p < .05; OR = 0). Analysis of hematologic parameters showed a significant decrease (p < .001) in platelets in coinfected patients compared with monoinfected patients. In conclusion, dengue-malaria coinfection is a reality in Ngaoundere city and associated with the appearance of clinical features which predict the disease severity.
Brice Ayissi Owona, Wilfred A. Abia, Paul Fewou Moundipa
International Immunopharmacology
Corinne Raïssa Ngnameko, Lucia Marchetti, Barbara Zambelli, Antonio Quotadamo, Davide Roncarati, Davide Bertelli and 5 more
Antibiotics
The medicinal plant Spathodea campanulata P. Beauv. (Bignoniaceae) has been traditionally applied for the prevention and treatment of diseases of the kidney and urinary system, the skin, the gastrointestinal tract, and inflammation in general. The present work shows for the first time how chemical components from this plant inhibit Helicobacter pylori growth by urease inhibition and modulation of virulence factors. The crude extract and the main fractions of S. campanulata bark were tested on H. pylori isolated strains and the active ones were further fractionated. Fractions and sub-fractions of the plant crude extract were characterized by ultra-high-performance liquid chromatographic tandem high resolution-mass spectrometry detection (UHPLC-HRMS). Several phenolics and triterpenoids were identified. Among the sub-fractions obtained, SB2 showed the capacity to inhibit H. pylori urease in a heterologous bacterial model. One additional sub-fraction (SE3) was able to simultaneously modulate the expression of two adhesins (HopZ and BabA) and one cytotoxin (CagA). The flavonol kaempferol was identified as the most interesting compound that deserves further investigation as a new hit for its capacity to modulate H. pylori virulence factors.
Faustin Pascal Tsagué Manfo, Christian Fusi Suh, Edouard Akono Nantia, Paul Fewou Moundipa, Fidelis Cho‐Ngwa
Toxicology Research
The efficiency of agro pesticides and fertilizers in eliminating pests and scaling up crop yield has motivated farmers to increase their use. Unfortunately, health hazards caused on farmers by these agrochemicals are of growing concern, though not well elucidated. In order to evaluate the effects of occupational exposure to agrochemicals on some key parameters of male farmers' health in Buea Subdivision, Cameroon, a total of 101 men, including 62 farmers using the agrochemicals and a reference population of 39 men not involved in occupational utilization of the agrochemicals, were interviewed on use of protective equipment, exposure symptoms and reproductive health status. Thereafter, serum cholinesterase [acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)] activities, total antioxidant capacity and reproductive hormones [follicle-stimulating hormone (FSH), luteinizing hormone and testosterone] were assessed. Results revealed that farmers mainly used insecticides followed by fungicides, herbicides and fertilizers, but with inadequate protective measures. The use of agrochemicals resulted in several exposure symptoms including weakness, itches, burning sensation, headache, sneezing, coughing and vomiting, as well as decrease in serum AChE activity when compared to the reference population. The agrochemicals impacted negatively on the farmers' reproductive health as evidenced by increased FSH levels. Taken altogether, these results suggested that exposure to agrochemicals adversely affects farmers' health. Therefore, there is a need to further sensitize the farmers on the use of protective equipment to mitigate the exposure and resulting health hazards.
André-Ledoux Njouonkou, Sandrine Appolonie Balla Ekobo, Frédéric Nico Njayou, Olivier Raspé, Paul Fewou Moundipa, Jérôme Degreef
Czech Mycology
Termitomyces species are among the most utilised mushrooms in tropical Africa and Asia, with some species having putative medicinal properties. However, data on their diversity, distribution, ethnomycology, biological activities and metabolites are still to be completed, especially in central Africa. During field surveys in the Western Highlands of Cameroon, basidiomes of a species of this fungal genus were collected and morphologically described. The extracts were used to screen and measure some antioxidant compounds and their respective activities, including polyphenols, flavonoids, thiols, DPPH radicals scavenging activity, ferric reducing power (FRAP) and the superoxide dismutase-like (SOD-like) activity in comparison to that of vitamin C. Morphological features allowed identifying this fungal species as Termitomyces reticulatus , which is here reported for the first time from Cameroon. This species is used by locals as food. Mycochemical antioxidant analyses revealed polyphenols as the major antioxidant compounds, followed by flavonoids and thiols. Extracts also showed significant DPPH, FRAP and SOD-like activities, although less strongly than those of vitamin C. The global antioxidant potential of this species is comparable to that of many mushroom species, such as T. heimii and T. microcarpus . Extensive work on other metabolites and biological activities of T. reticulatus are needed for a better description of its potential health benefits, especially in the fight against various human oxidative stress-related diseases.
Ghislaine Ndonkeu Mangoumou, Julienne Nguefack, Joseph Blaise Dongmo Lekagne, Charles Dakolé Daboy, Jean Claude Nguepsi, Paul Fewou Moundipa
International Journal of Environment Agriculture and Biotechnology
The impact of the combination of plant (Tithonia diversifolia) (Td) plus cow dung (Cd) as biofertilizer and aqueous extract of Callistemon citrinus (CAL) leaves as biofungicide on physicochemical properties, and the microbial biomass in carbon (MBC) and nitrogen (MBN) of soil and on tomato yield were assessed under field condition. The experimental design was a complete block design with 2 factors (soil amendment and plant sprays) and 3 repetitions. The soil treatment included organic amendment (OA): Td + Cd at the ratio of 3:4 (w/w)/plant; inorganic amendment (IA): 21:8:8 NPK (26.2g/plant) and potassium sulfate (4g/plant); and control (unamended soil). The field treatments were plants sprayed with: 5% (w/v) CAL; 5% (w/v) Mancozeb (M); and water (W). All amendments except IA did not significantly modify the soil organic matter (˂2.4mg.kg-1) and organic carbon content. An increase of 23.15% and 30.60% of calcium concentration and cation exchangeable capacity (CEC) respectively, was recorded in OA soil compared to the soil before cultivation (SBC) (P˂0.05). Copper and zinc contents in OA soil were reduced respectively by 49% and 48.5% compared to SBC. The highest concentration of MBC was recorded in OA.M plot. The different combine treatments (OA.CAL, IA.M, and OA.M) increased tomato yield by 3.4; 3; and 5.3 fold, respectively compared to their controls. This study provided new information about the organic amendment on soil and plant sprayed with C. citrinus extract as a green alternative to conventional input that might improve soil quality and crop yield.
Antoine Kada Sanda, Akono Edouard Nantia, T. F. Pascal Manfo, Romi T. Toboh, Roxane Essame Abende, Sterling Adaibum and 2 more
Drug and Chemical Toxicology
Parastar is an insecticide formulation of lambda-cyhalothrin and imidacloprid largely used for crop protection in North West Region of Cameroon. In the present study, we evaluated the behavioral activities and motor function of Wistar male rats after subchronic treatment with the pesticide formulation. To this end, three groups of adult rats were administered Parastar at doses 1.25, 2.49 and 6.23 mg/kg, respectively, for 35 days. A control group was included and received distilled water. At the end of the treatment, the animals were submitted to behavioral and functional tests (open field test, elevated plus maze test, light-dark box test, forced swimming test, tail suspension test, beam-walking test, grid suspension test and wire hang test) for estimation of anxiety, exploration, depression and motor coordination. Results revealed that Parastar, at the higher doses tested, 2.49 and 6.23 mg/kg, induced anxiogenic-like pattern behavior in rats in all behavioral assays including open field test (total distance moved, total lines crossed, frequency and total time in center square were all reduced), elevated plus maze (decreased total time spent in open arms and the number of entries in open arms of the elevated plus maze), and light-dark box (the dark box duration increased, while light box duration time and frequency of transition between dark and light box decreased). Treatment with 2.49 and 6.23 mg/kg Parastar increased the immobility time of animals in both forced swimming test and tail suspension test. The insecticide induced decrease in the distance traveled, foot slip and number of turns of animals in the beam walking test. Parastar also decreased the animal suspension time in both grid suspension grip-strength test and the wire hang test. Taken altogether, these results suggest that subchronic administration of Parastar at the doses of 2.49 and 6.23 mg/kg induced anxiety-like and depressive-like behavior as well as impaired motor coordination and muscle strength in male rats.
Marie Amougou‐Atsama, Paul Jean Adrien Atangana, Dominique Noah Noah, Paul Fewou Moundipa, Pascal Pineau, Richard Njouom
Journal of Viral Hepatitis
BACKGROUND: Hepatitis C virus (HCV) infection is known to be an important risk factor for hepatocellular carcinoma (HCC) in Cameroon. However, the effect of HCV-related factors on HCC development still remains unknown in the Central Africa. In this study, we investigated the role of HCV genotypes and core mutations in HCC development in Cameroonian patients. METHODS: A case-control study was conducted using patients with HCV-related HCC and matched controls individuals with chronic HCV infection but without HCC. HCV genotypes and mutations were determined using a hemi-nested amplification and sequencing analysis focus on the core and NS5B HCV regions. RESULTS: We identify HCV genotype 1, 2 and 4 in both groups. Interestingly, genotype 4 was significantly more prevalent in HCC patients (53.3%). Overall, distribution of genotypes was very different between cases and controls (P = 4.2 E-7). The risk factors analysis showed that infection with HCV-4 is strongly associated with HCC development with odd ratio, 95% confidence interval and p-values of 7.4 (95% CI: 2.08-26.6; P = .001). Furthermore, the risk of developing HCC increased even more significantly in case of infection with HCV subtype 4f with the odd ratio of 20.8 (95% CI, 4.1-66.8; P < .001). Mutations K10R, T72E, K74R and G77A were significantly more frequent in patients with HCC. Remarkably, HCV-4f isolates from HCC patients carried significantly more mutations when compared to controls with HCV-4f or others genotypes (P = .0001). CONCLUSIONS: Our results indicate that patients infected with HCV-4f or with selected variants affecting HCV core gene are at increased risk to develop HCC.
Fredy Brice Nemg Simo, Jean Joël Bigna, Sébastien Kenmoe, Marie S. Ndangang, Elvis Temfack, Paul Fewou Moundipa and 1 more
Scientific Reports
Abstract Better knowledge of the face of the current dengue virus (DENV) epidemiology in Africa can help to implement efficient strategies to curb the burden of dengue fever. We conducted this systematic review and meta-analysis to determine the prevalence of DENV infection in Africa. We searched PubMed, EMBASE, African Journals Online, and Africa Index Medicus from January 1 st , 2000 to June 10 th , 2019 without any language restriction. We used a random-effects model to pool studies. A total of 76 studies (80,977 participants; 24 countries) were included. No study had high risk of bias. Twenty-two (29%) had moderate and 54 (71%) had low risk of bias. In apparently healthy individuals, the pooled prevalence of DENV was 15.6% (95% confidence interval 9.9–22.2), 3.5% (0.8–7.8), and 0.0% (0.0–0.5) respectively for immunoglobulins (Ig) G, IgM, and for ribonucleic acid (RNA) in apparently healthy populations. In populations presenting with fever, the prevalence was 24.8% (13.8–37.8), 10.8% (3.8–20.6k) and 8.4% (3.7–14.4) for IgG, IgM, and for RNA respectively. There was heterogeneity in the distribution between different regions of Africa. The prevalence of DENV infection is high in the African continent. Dengue fever therefore deserves more attention from healthcare workers, researchers, and health policy makers.
Marie Atsama Amougou, Agnès Marchio, Berthold Bivigou‐Mboumba, Dominique Noah Noah, Robert Banaï, Paul Jean Adrien Atangana and 3 more
Journal of Viral Hepatitis
Worldwide, the development of hepatocellular carcinoma (HCC) is known to be influenced by several hepatitis B viral factors. However, the effect of hepatitis B virus (HBV) genotypes and a landscape of nucleotide changes affecting the precore (PC) and basal core promoter (BCP) during infection leading to HCC remain largely unknown in the Central Africa region. Thus, we performed a case-control study on patients with HBV-related HCC and matched controls without HCC but with chronic HBV infection. Genotypes and mutation spectrums were evaluated using a hemi-nested amplification and sequencing analysis focused on the BCP and PC regions. We identified the co-circulation of HBV quasi-subgenotype A3 (QS-A3) and genotype E in both groups. Interestingly, HBV-QS-A3 was significantly more prevalent in patients with HCC (80.0%) than in controls (31.9%, P = 4.5 E-7, OR = 11.5, 95% CI: 3.8-38.5). HBV mutation spectra and nucleotide changes were significantly more polymorphic in patients with HCC. Remarkably, HCC patients infected with HBV-QS-A3 were significantly more mutated compared to patients infected with genotype E (P < 0.0001). In addition, G:C>T:A transversions, generally associated with aflatoxin B1 exposure in tropical regions, were significantly more prevalent in HCC patients infected either with HBV-QS-A3 or HBV genotype E (P = 2.2 E-05) when compared to controls. In conclusion, our results indicate that patients infected with HBV-QS-A3 are at increased risk to develop HCC. In addition, viral genomes isolated for patients with tumour are more heavily altered than those found in controls. Preferential targeting of these patients for antiviral treatment is of paramount importance to reduce future HCC incidence in Cameroon.
Corinne Raïssa Ngnameko, Frédéric Nico Njayou, Muinah Fowora, Frédy Brice Simo Nemg, Paul Fewou Moundipa, Stella Smith
European Journal of Integrative Medicine
Viviane L. Ndam Ngoungoure, Patricia Muñoz, Yousef Tizabi, R Valdés, Paul Fewou Moundipa, Juan Segura‐Aguilar
Europe PMC (PubMed Central)
Aminochrome, an endogenous compound formed during dopamine oxidation can induce neurotoxicity under certain aberrant conditions and induce Parkinson-like syndrome. Glutathione transferase M2 (GSTM2) activity of astrocytes by catalysing the conjugation of aminochrome with glutathione, can offer protection against aminochrome toxicity. Some medicinal toxicity through this plants may exert protective effect against aminochrome mechanism.In the present study, extracts from plants native to Cameroon, such as Alchornea laxiflora (leaves), Dacryodes edulis (barks), Annona muricata (seeds), Annona senegalensis (barks) were evaluated for their protection against aminochrome-induced toxicity in human glioblastoma/ astrocytoma U373MG wild type and U373MGsiGT6 cells in which GSTM2 expression was 74% silenced. The cells were pre-incubated with the plant extracts for 2 hr before addition of aminochrome (75 μM) and measurement of cell death/viability by flow cytometry after 24 hr incubation.The extract of A. laxiflora (1 μg/ml), D. edulis (25 μg/ml), A. muricata (25 μg/ml) and A. senegalensis (25μg/ml) significantly decreased aminochrome-induced toxicity in U373siGST6 and U373MG cells. However, only A. laxiflora and A. muricata significantly increased the mitochondria membrane potential in U373siGST6 cells following aminochrome treatment.The results indicate that extracts of some Cameroon plants can provide protection against aminochrome-induced toxicity and mitochondria dysfunction in human glioblastoma/astrocytoma cells. Although further identification of active components of these extracts is needed, potential usefulness of these compounds in Parkinson's disease may be suggested.
Angèle N. Tchana, Nina D. Kamnang, Arielle T. Maliedje, Faustin Pascal Tsagué Manfo, Frederic N. Njayou, Wilfred A. Abia and 2 more
Journal of Pharmacy and Pharmacology
This study reports on the dietary exposure of people in Yaound, Cameroon to heavy metals: lead (Pb), cadmium (Cd), mercury (Hg), copper (Cu) and zinc (Zn). One hundred and fifty table-ready food, water and soft drink samples were collected from households and street restaurants in Yaound and analyzed for heavy metals contents using atomic absorption spectrophotometer. Lead (93%, range 0.019-1.77 ppm), Cd (70%, range 0.01-4.68 ppm), Hg (81%, range 0.03-10.56 ppm), Cu (90%, range 0.004-40.32 ppm) and Zn (87%, range 0.014-2,447.04 ppm) were detected in studied samples. Maximum level of each metal exceeded its corresponding European Commissions legislative limits. Samples from street restaurants were most tainted with heavy metals. The highest average daily intakes (ADIs) of Pb (0.96 mg/day) and Hg (1.84 mg/day) were through tap water, while Cd (1.15 mg/day), Cu (5.42 mg/day) and Zn (601.6 mg/day) were through rice/peanut sauce mixed food. The ADI for Cd and Hg was each higher than its respective PTDI (provisional tolerable daily intake) as defined by JECFA (Joint FAO/WHO Expert Committee on Food Additives) and EVM (Expert Group on Vitamins and Minerals). The estimated average daily exposure dose of each detected metal significantly (p = 0.001) exceeded its corresponding PTDI. However, the health risk index was < 1 for all studied samples and it was found to be safe, indicating there is a relative absence of health risks associated with the ingestion of contaminated foods, water and soft drinks. Notwithstanding, the detected levels and ADI being higher than legislative limits and PTDI respectively speculates need for awareness raising towards reducing exposure levels to heavy metals in Cameroon.
Fredy Brice Nemg Simo, Jean Joël Bigna, Estelle Amandine Well, Sébastien Kenmoe, F.B.Y. Sado, Scott C. Weaver and 2 more
Public Health
Marie Atsama Amougou, Paul Jean Adrien Atangana, Alice Ghislaine Ndoumba Afouba, Paul Fewou Moundipa, Pascal Pineau, Richard Njouom
BMC Research Notes
OBJECTIVE: This study evaluates the occurrence of the various morphological subtypes of hepatocellular carcinoma (HCC) and their connections with some risk factors in Cameroonian patients. The database of the 360 liver biopsies received and associated medical records were reviewed for histological and demographic analysis. Archival formalin-fixed and paraffin embedded liver biopsy specimens or slide were re-evaluated in malignancies patients. HCC classification was determined according to the World Health Organization criteria. RESULTS: Malignancies were confirmed in 24.7% (89/360) of liver biopsies. Primary liver tumors consisted in 80 cases of HCC and one case of hepatoblastoma. The distribution of the morphological variants of HCC was trabecular pattern (n = 45/80, 56.25%), acinar/pseudoglandular (32.5%) or scirrhous (11.2%). Remarkably, liver steatosis was present in 60.0% (48/80) of patients with HCC, most of them infected with hepatitis C virus (75.8%). Well-differentiated trabecular tumors were significantly associated with important fibrotic and necro-inflammatory activities in livers (P = 0.008) whereas acinar pattern was more frequent on fatty livers (P = 0.02). Our finding indicates that in Middle Africa the morphology of HCC subtypes correlates with changes affecting non-tumor liver tissue. Trabecular subtype is installed by strong liver injury whereas acinar pattern is more often associated with lipid metabolism defects.
Emma F. Bend, Pierre C. Oundoum Oundoum, Marie I. Ngaha Njila, Brice L. Koloko, Camille D. Nyonseu, Samuel Honoré Mandenguè and 3 more
Pharmacology & Pharmacy
The aim of the study was to bring scientific evidence of the curative action of the stem bark aqueous extract of Schumanniophyton magnificum (ASMa) on the sexual maturation and fertility of the immature female Wistar rat. Forty immature female rats were randomized and divided into 4 groups of ten animals each and orally treated with the ASMa at doses of 0 (distilled water), 200 mg/kg, 400 mg/kg and 800 mg/kg /BW/day for 30 consecutive days. Body weight and food intake were recorded throughout the experimental period. The precocity of the puberty onset in treated animals was evaluated through the determination of their age at vaginal opening. At the end of the experimental period, 5 animals in each group were sacrificed and blood samples were collected for hormonal assay. Their ovaries and uteri were removed, blotted, weighted and prepared for biochemical analysis. The remaining rats (5 per group) were crossed with males of proven fertility. After laparotomy (ten days after mating) and delivery, fertility and gestational parameters were recorded. It was noticed that, body weight gain increased significantly at all doses although there was no significant difference in food intake. The sexual maturation of treated animal was reduced to 5 days when compared to control. This was associated with the simultaneous elevation of FSH and LH (p mg/kg. However, the ovarian cholesterol significantly decreased (p mg/kg and 800 mg/kg. The animal treated at doses of 400 mg/kg and 800 mg/kg exhibited an early fertilization (2 - 3 days) when compared to the control one (9 - 14 days). The number of implantation site significantly increased (p mg/kg and 800 mg/kg) after laparotomy as well as the number of alive fetuses after delivery and gestational rate (80% and 100%) respectively. These results provide the strong evidence on the induction of the onset puberty and gonadotropin synthesis, the improvement of the ovarian folliculogenesis and the fertility effect of ASMa in immature rats.
Arnaud Fondjo Kouam, Fei Yuan, Frédéric Nico Njayou, Hongtao He, Romeo Fouemene Tsayem, Babayemi Olawale Oladejo and 3 more
Frontiers in Pharmacology
Drug-induced liver injury (DILI) is a major clinical problem where natural compounds hold promise for its abrogation. Khaya grandifoliola (Meliaceae) is used in Cameroonian traditional medicine for the treatment of liver related diseases and has been studied for its hepatoprotective properties. Till date, reports showing the hepatoprotective molecular mechanism of the plant are lacking. The aim of this study was therefore to identify compounds from the plant bearing hepatoprotective activity and the related molecular mechanism by assessing their effects against acetaminophen (APAP)-induced hepatotoxicity in normal human liver L-02 cells line. The cells were exposed to APAP (10mM) or co-treated with phytochemical compounds (40 μM) over a period of 36h and, biochemical and molecular parameters assessed. Three known limonoids namely 17-epi-methyl-6-hydroxylangolensate, 7-deacetoxy-7-oxogedunin and deacetoxy-7R-hydroxygedunin were identified. The results of cells viability and membrane integrity, reactive oxygen species generation and lipid membrane peroxidation assays, cellular glutathione content determination as well as expression of cytochrome P450 2E1 demonstrated the protective action of the limonoids. Immunoblotting analysis revealed that limonoids inhibited APAP-induced c-Jun N-terminal Kinase phosphorylation (p-JNK), mitochondrial translocation of p-JNK and Bcl2-associated X Protein, and the release of Apoptosis-inducing Factor into the cytosol. Interestingly, limonoids increased the expression of Mitogen-activated Protein Kinase Phosphatase (Mkp)-1, an endogenous inhibitor of JNK phosphorylation and, induced the nuclear translocation of Nuclear Factor Erythroid 2-related Factor-2 (Nrf2) and decreased the expression of Kelch-like ECH-associated Protein-1. The limonoids also reversed the APAP-induced decreased mRNA levels of Catalase, Superoxide Dismutase-1, Glutathione-S-Transferase and Methionine Adenosyltransferase-1A. The obtained results suggest that the isolated limonoids protect L-02 hepatocytes against APAP-induced hepatotoxicity mainly through increase expression of Mkp-1 and nuclear translocation of Nrf2. Thus, these compounds are in part responsible of the hepatoprotective activity of K. grandifoliola and further analysis including in vivo and toxicological studies are needed to select the most potent compound that may be useful as therapeutic agents against DILI.
Frédéric Nico Njayou, Arnaud Fondjo Kouam, Brice Fredy Nemg Simo, Angèle N. Tchana, Paul Fewou Moundipa
BMC Complementary and Alternative Medicine
BACKGROUND: Khaya grandifoliola (Meliaceae) and Entada africana (Fabaceae) are traditionally used in Bamun (a western tribe of Cameroon) traditional medicine for the treatment of liver related diseases. In this study, the synergistic hepatoprotective effect of respective active fractions of the plants were investigated against paracetamol-induced toxicity in primary cultures of rat hepatocytes. METHODS: Paracetamol conferred hepatocyte toxicity, as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay, alanine aminotransferase (ALT), superoxide dismutase (SOD), catalase (CAT) activities, malondialdehyde (MDA) and glutathione (GSH) content assays. The crude extracts were fractionated by flash chromatography and fractions were tested for hepato-(protective and curative) activities. The most active fractions of both plants were tested individually, and in combination based on their respective half effective concentration (EC50). RESULTS: The methylene chloride/methanol fractions of K. grandifoliola (75:25 v/v) (KgF25) and E. africana (90:10 v/v) (EaF10) were found to be the most hepato-protective with EC50 values of 10.30 ± 1.66 μg/ml and 13.47 ± 2.06 μg/ml respectively, comparable with that of silymarin (13.71 ± 3.87 μg/ml). These fractions and their combination significantly (P <0.05) improved cell viability, inhibited ALT leakage and MDA formation, and restored cellular CAT, SOD activities and GSH content. The combination was more effective in restoring biochemical parameters with coefficients of drugs interaction (CDI) less than 1. CONCLUSION: These findings demonstrate that the active fractions have synergistic action in the protection of rat hepatocytes against paracetamol-induced damage and suggest that their hepatoprotective properties may be maximized by using them in combination.
Edouard Akono Nantia, David Moreno‐González, Faustin Pascal Tsagué Manfo, Sonchieu Jean, Paul Fewou Moundipa, Ana M. Garcı́a-Campaña and 1 more
Analytical Letters
With the increased use of chemicals in agriculture for crop protection and improvement of yield, the contamination of water is currently a serious health concern. This study used solid-phase extraction with ultra-high-performance liquid chromatography–tandem mass spectrometry to evaluate the presence of 23 carbamate pesticides in waters from Cameroon. The separation was achieved in 5.5 min using a C18 column (50 × 2.1 mm, 1.8 µm) with a mobile phase composed of water and methanol each containing 0.01% formic acid. The analytes were determined in positive multiple reaction monitoring mode. The recoveries for fortified water were from 75 to 99%, with relative standard deviations below 13%. The limits of detection ranged from 0.003 to 0.397 µg L−1. The reported method is simple, sensitive, and accurate, and is a suitable alternative for routine monitoring of pesticide residues at ultra-trace levels. The analysis revealed the presence of propoxur at a concentration of 0.072 µg L−1 in stream water.
Borris Rosnay Galani Tietcheu, Richard Njouom, Paul Fewou Moundipa
Journal of Translational Internal Medicine
Chronic hepatitis C is a major public health problem in sub-Saharan countries and particularly in Cameroon where the prevalence rate is around 7.6% in the age group of 55-59 years. Recent investigations into this infection allowed defining a national seroprevalence, characterizing virological and biological profiles of infected patients and identifying medicinal plants of potential interest in hepatitis C therapy. However, in Cameroon, no existing report currently presents a good overview of hepatitis C research in relation to these parameters. This review seeks to discuss major findings published since 2001 that have significantly advanced our understanding of the epidemiology and treatment of hepatitis C in Cameroonian patients and highlight the major challenges that remain to overcome. We performed a systematic search in Pubmed and Google Scholar. Studies evaluating prevalence, treatment, coinfection, and genetic diversity of HCV infection in Cameroon were included. Studies suggest that HCV prevalence in Cameroon would be low (around 1.1%) with a lot of disparities according to regions and age of participants. Elders, pregnant women, blood donors, health care workers, patients on hemodialysis, and homozygous sickle cell patients have been identified as risk groups. Moreover, HCV/HBV coinfection was found more prevalent than HCV/HIV coinfection. Phylogenic studies reported circulation of three main genotypes such genotypes 1, 2, and 4 but little is known about antiviral candidates from the Cameroonian pharmacopeia. In conclusion, some epidemiological data prove that hepatitis C in Cameroon is well known but efforts are still necessary to prevent or control this infection.
Ida Marlene Guiatau Tamo, Marceline Djuidje Ngounoue, Axel Cyriaque Ambassa, Paul Fewou Moundipa
Journal of the Cameroon academy of sciences
Viral infection continues to be a major cause of morbidity and mortality in the world in particular those caused by the Hepatitis C virus (HCV) and the Human Immunodeficiency virus (HIV). The aim of this study was to evaluate the importance of the biochemical exploration of the liver function in the control of disease progression in people living with HIV/AIDS and co-infected by HIV and hepatitis C virus. Sera from 75 patients positive for HIV were screened for HCV antibody by immuno-chromatographic test in Yaounde central hospital, from November 2015 to February 2016. The biochemical parameters (AST, ALT, CB, TB, γ-GT, ALP and creatinin), as well as CD4 T cell level determination were assessed following standard procedures. A second blood sample was taken from HIV mono-infected and HIV/ HCV co-infected after three months. Socio-demographic data were also collected. The data were entered and analyzed using SPSS version 22.1 statistical software and p<0.05 was considered as statistically significant. Amongst 75 study patients, 10 (13.3%) were HIV/HCV co-infected. The results obtained showed that, the activity of γ-GT was significantly higher (P <0.0001) in HIV/HCV co-infected patients compared to HIV mono-infected patients. The concentration of total bilirubin was also significantly higher in HIV/HCV co-infected patients (P = 0.015). Biochemical analysis using the second blood sample carried out 3 months later, after first sample, showed a significant increase of creatinin observed in HIV monoinfected patients, but no significant increase of some biochemical parameters (ALT, Creatinin, total Bilirubin, conjugated Bilirubin) was observed in HIV/HCV co-infected patients. In HIV / HCV co-infected patients, the first blood sample showed a significant increase of γ-GT (118.36±75.95 IU) compared to HIV mono-infected patients, in the Yaounde Central Hospital. From this observation, hepatic damage should be evaluated by analyzing biochemical parameters. Key words : Liver enzyme, Co-infection, HIV, HCV, control
Borris Rosnay Galani Tietcheu, Marie-Emmanuelle Sahuc, Gabriele Sass, Frédéric Nico Njayou, Christine E. Loscher, Pierre Mkounga and 6 more
Archives of Virology
Richard Simo Tagne, Bruno Phélix Telefo, Emmanuel Talla, Jean Noël Nyemb, Sylvain Nguedia Njina, Muhammad Asrar and 5 more
Asian Pacific Journal of Tropical Disease
To investigate the anticancer and antioxidant potential of methanol bark extract of Ziziphus mauritiana (Z. mauritiana), which is used by traditional healers to cure some cases of cancer in Cameroon. The methanol crude extract of Z. mauritiana has the antiproliferative activity on four cancer cell lines and its antioxidant activity. The extract was partitioned in five different solvents, and each fraction was tested. The effect of the most antiproliferative fraction on cell cycle was determined. Bio-guided fractionation was performed on the fraction with the highest antiproliferative and the highest antioxidant activities. Z. mauritiana methanol extract was active on all tested cells, and showed promising antioxidant activity. All fractions except hexane fraction were active with the dichloromethane fraction being the most active and showed S and G2-M phase arrest (P<0.01) on cell cycle progression of NCI-H460 and MCF-7, respectively. Bio-guided fractionation of the dichloromethane fraction led to lupeol and betulinic acid. The greatest antioxidant activity was recorded with ethyl acetate fraction and its fractionation led to catechin and epigallocatechin. Overall, this study showed that Z. mauritiana barks has benefits as a chemoprevention agent cancer.
Marceline Djuidje Ngounoue, Appolinaire Djikeng, David Spiro, Madeleine Mbangue, Honoré Fotso Kuate, Paul Fewou Moundipa and 1 more
Journal of the Cameroon academy of sciences
Background: RNA virus infections represent a significant cause of illness and death in vertebrates. Specifically in humans, RNA viruses are responsible for a wide range of acute, chronic, emerging and re-emerging infections. HIV and HCV rank as some of the most severe RNA viruse infections facing Africa. Methods: To determine genotypes and subtypes of HIV and HCV among co-infected patients in Cameroon, viral RNA was isolated from HIV/HCV co-infected individuals, in Douala, Cameroon. A total of 36 HIV/HCV co-infected isolates (22 from volunteer blood donors and 14 from people living with HIV/AIDS not yet on antiretroviral treatment) were analyzed using molecular biology techniques that involved RT-PCR, gene/TOPO cloning, DNA sequencing, and bioinformatics tools for sequence management and analysis. Epidemiological data were examined as well. Results: Results show that HIV strains isolated belong to the circulating recombinant forms CRF02_AG, whereas HCV isolates from Cameroon belong to genotypes 1, 2, and 4. The corresponding HCV subtypes investigated were 1a, 1b, 1c, 2a, 2c, 2k, and 4a. Subtypes 1a and 1b, most frequently found in developed countries, also circulate in Cameroon. Epidemiologic data show that HIV/HCV co-infected patients are older than HIV mono-infected patients. Conclusions: These results indicate that HIV/HCV co-infection represent a significant threat in Cameroon. There is evidence of genetic diversity of HIV and HCV; virulent hepatitis C virus subtypes 1a and 1b circulate in Cameroon. An epidemiological and molecular database on HIV and HCV is necessary for the development of further intervention in Cameroon as an imperative for monitoring disease progression. Key words: HIV; HCV; Co-infection ; Genotypes ; Virulent.
Didiane Mefokou Yemele, Bruno Phélix Telefo, Stephanie Chekem Goka, Benoit Telesphore Nguelefack, Pierre Simeon chegaing Fodouop, Richard Simo Tagne and 3 more
International Journal of Phytomedicine
Normal 0 21 false false false FR X-NONE X-NONE MicrosoftInternetExplorer4 In Cameroon, many plants are used in traditional medicine for the treatment of pregnancy and childbirth complaints. However, toxicological potential of most of these plants have not been investigated. In order to evaluate the degree of safety of their users, in vitro cytotoxic potentials of sixteen of these medicinal plants were subjected to the assay using the brine shrimp lethality assay. From this study, the aqueous extract of plant Rauvolfia vomitoria bark was found to be cytotoxic and that of Ageratum conyzoides stem and leaves slightly cytotoxic, with LC 50 values of 17.62 and 99.17µg/ml, respectively. The least toxic plant extracts were Aloe buttneri, Commelina benghalensis, Ipomoea tenuirostris and Nelsonia canescens, (LC50 value > 10 5 µg/ml). Overall fourteen extracts were found to be non-toxic. Most herbal remedies were non cytotoxic but it would be necessary to complete these cyto-toxicological information by mutagenicity, teratogenicity tests as welle as in vivo toxicological tests on animals. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tableau Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-fareast-language:EN-US;}
Borris Rosnay Galani Tietcheu, Marie-Emmanuelle Sahuc, Frédéric Nico Njayou, Gaspard Deloison, Pierre Mkounga, William F. Feudjou and 5 more
Frontiers in Microbiology
According to some recent studies, Cameroon is one of the sub-Saharan African countries most affected by hepatitis C, with low access to the standard therapy based on the combination of pegylated interferon and ribavirin. A first ethnobotanical survey, conducted in the Western region of Cameroon, reported the use of several medicinal plants in traditional medicine for the healing of liver-related disorders. Crude organic extracts of five plants surveyed were prepared and their effect against hepatitis C virus (HCV) infection investigated. The HCV JFH1 strain cell culture system HCVcc was used. The antiviral activity was quantified by immunofluorescent labeling of HCV E1 envelope protein at 30 h post-infection in the presence of the plant extracts. Active compounds were then tested in time course infection experiments. Dose-response and cellular toxicity assays were also determined. Three extracts, methanol extracts from roots of Trichilia dregeana, stems of Detarium microcarpum and leaves of Phragmanthera capitata, showed anti-HCV activity, with half-maximal inhibitory concentration of 16.16, 1.42, and 13.17 μg/mL, respectively. Huh-7 cells were incubated with the extracts for 72 h and it appears that T. dregeana extract is not toxic up to 200 μg/mL, D. microcarpum up to 100 μg/mL and P. capitata up to 800 μg/mL. All the three extracts showed a strong inhibition of HCV entry and no effect on replication or secretion. Taken together, these results showed that extracts from Cameroonian medicinal plants are promising sources of anti-HCV agents.
Richard Simo Tagne, Bruno Phélix Telefo, Jean Noël Nyemb, Didiane Mefokou Yemele, Sylvain Nguedia Njina, Stéphanie Marie Chekem Goka and 4 more
Asian Pacific Journal of Tropical Medicine
OBJECTIVE: To obtain a scientific basis of the use of plant-derived preparations by many rural people in Cameroon, for their primary health care needs in the treatment of diseases such as cancer. METHODS: The antiproliferative effect of 11 plants methanol crude extracts on four cancer cells using sulforhodamine-B assay and their antioxidant activities using 1-diphenyl-2-picrylhydrazyl radical and nitric oxide radical scavenging ability were investigated. The Ekebergia senegalensis (E. senegalensis) and Protea elliotii (P. elliotii) extracts were selected based on their antioxidant and anticancer activities, and partition in hexane, dichloromethane, ethyl acetate, butanol and methanol was done. Each fraction was submitted to antioxidant and anticancer activities, and the effect of the dichloromethane fraction (the most antiproliferative fraction) on NCI-H460 cell cycle was determined by flow cytometry. RESULTS: The most antiproliferative substances were found for the extracts from E. senegalensis, P. elliotii, Terminalia macroptera and Vitellaria paradoxa. Whereas the most antioxidant substances were found for the extracts from Cissus populnea, E. senegalensis, P. elliotii, Terminalia macroptera, Vitellaria paradoxa, and Gardenia aqualla. Dichloromethane fraction of P. elliotii was found to be highly antiproliferative to NCI-H460 cancer cells and showed S phase arrest cell cycle progression. Ethyl acetate n-butanol and methanol fractions showed quite strong antioxidant activity for both E. senegalensis and P. elliotii, as compared to that of gallic acid. CONCLUSIONS: Overall, the antiproliferative and antioxidant activities of some of the extracts lend some support to their use in the traditional medicine of Adamawa Region, Cameroon to treat cancer.
Emmanuel Mfotie Njoya, Christian Weber, Nora Adriana Hernández‐Cuevas, Chung-Chau Hon, Yves L. Janin, Melanie F. G. Kamini and 2 more
PLoS neglected tropical diseases
Leaves of Codiaeum variegatum ("garden croton") are used against bloody diarrhoea by local populations in Cameroon. This study aims to search for the active components from C. variegatum against Entamoeba histolytica, and thereby initiate the study of their mechanism of action. A bioassay-guided screening of the aqueous extracts from C. variegatum leaves and various fractions was carried out against trophozoites of E. histolytica axenic culture. We found that the anti-amoebic activity of extracts changed with respect to the collection criteria of leaves. Thereby, optimal conditions were defined for leaves' collection to maximise the anti-amoebic activity of the extracts. A fractionation process was performed, and we identified several sub-fractions (or isolated compounds) with significantly higher anti-amoebic activity compared to the unfractionated aqueous extract. Anti-amoebic activity of the most potent fraction was confirmed with the morphological characteristics of induced death in trophozoites, including cell rounding and lysis. Differential gene expression analysis using high-throughput RNA sequencing implies the potential mechanism of its anti-amoebic activity by targeting ceramide, a bioactive lipid involved in disturbance of biochemical processes within the cell membrane including differentiation, proliferation, cell growth arrest and apoptosis. Regulation of ceramide biosynthesis pathway as a target for anti-amoebic compounds is a novel finding which could be an alternative for drug development against E. histolytica.
Dieudonné Massoma Lembè, Brice Koloko, Emma F. Bend, Judith Domkam, P. Oundoum Oundoum, Marie Ngaha Njila and 3 more
Journal of Experimental and Integrative Medicine
Objectives: Medicinal plants are of great value in the field of treatment and cure of diseases, beside their strategic value in drug supply. This study has investigated the effects of Rauvolfia vomitoria bark extract on reproductive functions of male rats. Methods: Thirty adult male rats were randomly assigned into 5 groups and orally treated with vehicle, 25, 50, 100, 200 mg/kg body weight per day of Rauvolfia vomitoria aqueous extract for 21 days. At the end of treatment, animals were sacrificed. Hormone and biochemical analysis were done. Testis and accessory organs were removed and weighed. Sperm count, transit and motility were also evaluated. Results: After 21 days of treatment, body weight was slightly reduced dose-dependently. The relative weight of testis significantly increased at high doses (100 and 200 mg/kg), while the relative weight of the prostate and seminal vesicles also significantly increased in all treated animals. The daily sperm production at high doses as well as the sperm count in epididymis and vas deferens at low doses (25 and 50 mg/kg), showed a significant difference between experimental groups and control group. The sperm motility and transit was significantly higher at low doses when compared to control. Testicular and epididymal protein significantly increased at low doses, while the testicular cholesterol significantly increased at all doses when compared to control. The highest effect on testosterone level was observed at the dose of 200 mg/kg of Rauvolfia vomitoria. Conclusion: These results indicate that treatment with the aqueous extract of Rauvolfia vomitoria could improve the fertility of male rats.
Emmanuel Mfotie Njoya, Paul Fewou Moundipa, Helga Stopper
Journal of Ethnopharmacology
Richard Simo Tagne, Bruno Phélix Telefo, Sylvain Nguedia Njina, B. Vasantha bala, Stéphanie Marie Chekem Goka, Didiane Mefokou Yemele and 5 more
Asian Pacific Journal of Tropical Disease
To evaluate the in vivo anti-androgenic, antioxidant activity and anti-estrogenic activities of Eremomastax speciosa (E. speciosa) in order to find new method for fighting against chronic diseases such as cancer. Evaluations of antiandrogenic and antioxidant activities were carried out on male rate receiving simultaneous daily administration of testosterone and different doses of aqueous extract of E. speciosa, during a period of 10 d. The evaluation of antiestrogenic activity was carried out on mature ovariectomized female rats receiving simultaneous daily administration of estradiol and different doses of extract, for a week. Then reproductive organs were weighted, levels of prostatic acid phosphatase, superoxide dismutase and catalase as well as some hematologic parameters were measured. The treatment significantly reduced (P<0.01) the weight of ventral prostate, penis, Cowper's gland and the level of serum prostatic acid phosphatase; while a significant decrease (P<0.01) of the catalase activity was observed. A significant increase (P<0.05) in the lymphocyte number and significant decrease of monocyte (P<0.05) were noticed. The uterine relative weight were significantly reduced (P<0.01). Generally, these results denote the antiandrogenic, antiestrogenic and immunomodulatory potential of E. speciosa.
Viviane L. Ndam Ngoungoure, Jan Kevin Schluesener, Paul Fewou Moundipa, Hermann J. Schluesener
Molecular Nutrition & Food Research
Polyphenols are a large group of phytonutrients found in herbal beverages and foods. They have manifold biological activities, including antioxidative, antimicrobial, and anti-inflammatory properties. Interestingly, some polyphenols bind to amyloid and substantially ameliorate amyloid diseases. Misfolding, aggregation, and accumulation of amyloid fibrils in tissues or organs leads to a group of disorders, called amyloidoses. Prominent diseases are Alzheimer's, Parkinson's, and Huntington's disease, but there are other, less well-known diseases wherein accumulation of misfolded protein is a prominent feature. Amyloidoses are a major burden to public health. In particular, Alzheimer's disease shows a strong increase in patient numbers. Accelerated development of effective therapies for amyloidoses is a necessity. A viable strategy can be the prevention or reduction of protein misfolding, thus reducing amyloid build-up by restoring the cellular aggretome. Amyloid-binding polyphenols affect amyloid formation on various levels, e.g. by inhibiting fibril formation or steering oligomer formation into unstructured, nontoxic pathways. Consequently, preclinical studies demonstrate reduction of amyloid-formation by polyphenols. Amyloid-binding polyphenols might be suitable lead structures for development of imaging agents for early detection of disease and monitoring amyloid deposition. Intake of dietary polyphenols might be relevant to the prevention of amyloidoses. Nutraceutical strategies might be a way to reduce amyloid diseases.
I. Cesari, Mélanie Hoerlé, Cláudia A. Simões‐Pires, Pietro Grisoli, Emerson Ferreira Queiroz, Cesare Dacarro and 7 more
Journal of Ethnopharmacology
Wilfred A. Abia, Benedikt Warth, Michael Sulyok, Rudolf Krska, Angèle N. Tchana, Patrick Berka Njobeh and 5 more
Food and Chemical Toxicology
Wilfred A. Abia, Grace Nella Simo, Benedikt Warth, Michael Sulyok, Rudolf Krska, Angèle N. Tchana and 1 more
PubMed
For the first time in Cameroon, this paper reports on multiple mycotoxins occurrences in poultry feeds. Twenty feed samples collected from different poultry farms were analyzed for 320 fungal metabolites by liquid chromatography electrospray ionization tandem mass spectrometry. Results showed feeds contamination by 68 metabolites including 18 mycotoxins/metabolites currently regulated in the European Union such as fumonisins B1 (FB1), B2, and B3; deoxynevalenol (DON); and beta-zearalenol recovered in all samples. FB1 reported highest FB mean level of 468 (range 16-1930) microg kg(-1). Levels of DON and ZEN were mostly concentrated in feeds from western-highlands conversely for FBs and aflatoxins concentrations in Yaounde. Aflatoxin B1 mean level of 40 microg kg(-1) exceeded the worldwide permitted limit for aflatoxins in feed and generally inversely proportional to weight gain in chicken.
Brice Ayissi Owona, Nico Fréderic Njayou, Stefan Laufer, Hermann J. Schluesener, Paul Fewou Moundipa
BMC Complementary and Alternative Medicine
BACKGROUND: Inflammatory response in the CNS mediated by microglia cells play an important role in host defense and is implicated in the pathology of neurodegenerative diseases. We investigated the capacity of Entada africana to protect microglia from inflammatory insults by exploring the effect of the CH₂Cl₂/MEOH 5% fraction (Ea5) on pro-inflammatory cytokines mRNA expression. Finally, we studied the effect of Ea5 on the inhibition of p38 MAPK Kinase. The results were compared to those obtained with Baicalin, a well reported anti-inflammatory flavonoid. METHODS: Barks from E. africana were harvested in 2010, in the west region of Cameroon. A crude extract was prepared using CH₂Cl₂/MEOH 1:1 V/V. The crude extract obtained was further fractionated by flash chromatography. A mouse microglia cell line (N9) was stimulated by LPS with or without different concentrations of Baicalin and Ea5. The release of NO was evaluated using the Griess method. The expression of pro-inflammatory cytokines mRNA (TNFα, IL-1β, IL-6) and iNOS/NO were measured by RT- PCR. The inhibition of p38 MAPK Kinase was assessed using ELISA. RESULTS: We found that Ea5, as well as Baicalin inhibited LPS-induced NO production in a dose dependent manner. Ea5 was most active in term of NO inhibition (87.07%), in comparison to Baicalin (70.85%). The expression of TNFα, IL-1β, IL-6 and iNOS was strongly suppressed by Ea5 in microglia. Ea5 also inhibited the activity of p38MAPK Kinase, up to 30% for the concentrations tested, whereas a prominent inhibition was obtained with Baicalin. CONCLUSION: These results suggest that E. africana may contain promising compounds useful for the treatment of diseases cause by over-activation of microglia such as Alzheimer disease and other neurological diseases.
I. Cesari, Emerson Ferreira Queiroz, Quentin Favre-Godal, Laurence Marcourt, Gabriele Caccialanza, Paul Fewou Moundipa and 2 more
Phytochemistry
Frédéric Nico Njayou, E. C. E. Aboudi, M. K. Tandjang, A. K. Tchana, B.T. Ngadjui, Paul Fewou Moundipa
Khaya grandifoliola (Meliaceae) and Entada africana (Fabaceae ) are traditionally used as source of medicines against liver related d iseases. But the most efficient solvent to extract the plants bioactive compounds h as not yet been found. This work aimed at evaluating and comparing the hepatoprotect ive and antioxidant activities of Hexane (HE), methylenechloride-methanol (MCME) and water (WE) extracts of the plants stem bark. The hepatoprotective activity was evaluated by acetaminopheninduced damage in rat liver slices in measuring lac tate dehydrogenase (LDH) leakage as toxicity marker. The antioxidant activity was as sessed by using 2, 4-diphenyl-1picryl-hydrazil (DPPH), β-carotene-linoleic acid system ( β-CLAMS) and microsomal lipid peroxidation (MLP) assays. The MCME extract of both plants efficiently decreased LDH leakage from liver slices. At the tes ted concentration of 100µg/ml, the hepatoprotective percentage of the extract of K. grandifoliola (87.15%) and that of silymarine (93.73%) were comparable. In the antioxi dant study, the MCME and WE extracts of both plants performed well in inhibitin g MLP assay but, the MCME extracts were the more antioxidant with IC 50 values of 2.7±0.05µg/ml and 0.50±0.07µg/ml comparable with Trolox (2.27±0.52µg/ml) for K. grandifoliola and E. africana , respectively. Phytochemically, many classes of co mpounds including polyphenols were tested positive in the MCME extracts. From the interesting activity of these extracts, it might be concluded that methy lenechloride-methanol (1:1v/v) mixture is the most efficient solvent to extract he patoprotective and antioxidant active principles from K. grandifoliola and E. africana stem bark.
Edouard Akono Nantia, Faustin Pascal Tsagué Manfo, Nathalie Beboy, Paul Fewou Moundipa
Oxidants and Antioxidants in Medical Science
The methanol extract of Basella alba (MEBa) has been shown to improve male fertility. In order to further understand its action mechanism, its antioxidant effect was investigated in vitro. To this respect, the extract was tested on antioxidant enzyme activities and lipid peroxidation using rat testicular homogenate. Furthermore, the effect of the MEBa on oxidation of β-carotene, reduction of ferric ions and scavenging of free radicals was investigated; in addition, phytochemical analyses were performed. The MEBa slightly reduced diphenyl-picrylhydrazyl (DPPH) radical, and inhibited lipid peroxidation and β-carotene oxidation. The MEBa also reduced ferric ions and stimulated the activities of glutathione reductase, catalase and superoxide dismutase. These findings suggest antioxidant properties of MEBa, that could be attributed to phenolic compounds revealed by phytochemical studies of the extract. The MEBa antioxidant properties may thus sustain its various biological activities, such as improvement of male reproductive function.
Faustin Pascal Tsagué Manfo, Edouard Akono Nantia, H. Déchaud, Angèle N. Tchana, M. T. Zabot, Michel Pugeat and 1 more
Pharmaceutical Biology
CONTEXT: Male infertility is one of the leading causes of social frustration and marginalization, mainly in the developing world. It is attributed to many factors including exposure to agropesticides such as manganese ethylenebis (dithiocarbamate) (maneb), which is one of the most frequently used fungicides in Cameroon. Previous reports support efficiency of some medicinal plants commonly used in Cameroonian folk medicine for the treatment of this disorder. OBJECTIVE: The present study was aimed at assessing the protective effect of extracts from selected plant species, namely Basella alba L. (Basellaceae) (MEBa) and Carpolobia alba G. Don (Polygalaceae) (AECa), in alleviating the maneb-induced impairment of male reproductive function in Wistar albino rats. MATERIALS AND METHODS: The rats were treated with vehicle, plant extract (MEBa or AECa), maneb and maneb plus plant extract, respectively, and their fertility was assessed. Animals were thereafter sacrificed and organs (liver, kidneys and reproductive organs) were dissected out and weighed. Serum androgens together with alanine aminotransferase, liver glutathione and thiobarbituric acid reactive species (TBARS) were also measured. RESULTS AND DISCUSSION: From this study, both plant extracts stimulated testosterone and improved fertility. Administration of MEBa plus maneb prevented fertility reduction by maneb and minimized the inhibitory effect of maneb on testosterone levels. AECa also improved fertility of the maneb-exposed rats, though without restoring testosterone levels, and other investigated parameters remained unaffected by different treatments. CONCLUSION: These findings emphasized the beneficial effects of B. alba and C. alba extracts on male fertility, and suggest their protective effect against maneb-induced toxicity in male reproductive function.
Faustin Pascal Tsagué Manfo, Wen-Fang Chao, Paul Fewou Moundipa, Michel Pugeat, Paulus S. Wang
Drug and Chemical Toxicology
Maneb (Manganese ethylene-bis-dithiocarbamate) is a widely used fungicide in agriculture. In order to investigate its effect on male reproductive function, rats were intraperitonealy injected with maneb (1 and 4 mg/kg) for 9 or 18 days. After 6 and 14 days of treatment, the animals received human chorionic gonadotropin (hCG) via a jugular catheter and blood samples were collected at several intervals subsequent to the challenge. They were thereafter decapitated after 9 or 18 days, and organs (i.e., liver, seminal vesicles, and kidneys) were weighed. Leydig cells prepared from rats after 18 days of treatment were incubated with or without different stimulators or precursors [hCG, A23187, 25-OH-cholesterol (25-OH-C), or androstenedione] for 1 hour, and the media were analyzed for testosterone or pregnenolone. Liver glutathione and thiobarbituric acid reactive substances (TBARS) as well as serum alanine aminotransferase (ALT) activity were also measured. Further, Leydig cells and testicular interstitial cells (TICs) prepared from normal rats were incubated with maneb (3-100 µM) for 1 or 2 hours, and testosterone release was assessed. The results showed that administration of maneb (4 mg/kg) for 9 and 18 days did not alter liver function, but resulted in a decrease of basal level of plasma testosterone (P < 0.01). In addition, basal testosterone and pregnenolone release by Leydig cells prepared from maneb 18-day treated animals were significantly reduced (P < 0.05). However, acute in vitro exposure of TIC or Leydig cells to maneb did not alter their testosterone release. These results suggested that maneb alters testosterone production, at least in part, through inhibition of CYP11A1 activitiy.
Edouard Akono Nantia, Carine Travert, Faustin Pascal Tsagué Manfo, Serge Carreau, Thomas K. Monsees, Paul Fewou Moundipa
International Journal of Molecular Sciences
In this study, Leydig cells were purified from 70 day-old Sprague Dawley male rats and incubated with 10 and 100 μg/mL of methanol extract of Basella alba (MEBa) for 4 hours followed by the evaluation of cell viability, steroid (testosterone and estradiol) production, and the level of aromatase mRNA. Results showed that MEBa did not affect Leydig cell viability. At the concentration of 10 μg/mL, MEBa significantly stimulated testosterone and estradiol production (p < 0.01 and p < 0.03, respectively), and enhanced aromatase mRNA level (p < 0.04). These observations suggest that MEBa directly stimulated testosterone, estradiol and aromatase mRNA levels in isolated Leydig cells.
Faustin Pascal Tsagué Manfo, Edouard Akono Nantia, Angèle N. Tchana, Thomas K. Monsees, Paul Fewou Moundipa
Journal of Applied Animal Research
In order to assess the effect of Carpolobia alba on male reproductive function, its aqueous extract was tested on lactate release by rat Sertoli cell cultures. The extract was administered daily to adult male rats. After 60 days of treatment, the animals were sacrificed and weight of organs (liver, kidneys, testes, epididymides, seminal vesicles and prostate) recorded. Liver glutathione levels and aniline hydroxylase activity, epididymal α-glycosidase activity, as well as serum testosterone level and aminotransferase activities were also assessed. Carpolobia alba extract at the doses 0.01 and 0.1 mg/kg significantly increased serum testosterone levels (P<0.01) in male rats, while other investigated parameters on serum and Sertoli cells remained unchanged. These results proved the androgenic effect of C. alba and thereby, sustain its use in the management of male infertility.
Hubert J. Donfack, Rodrigue T. Kengap, B. Ngameni, Pascal Dieudonné Djamen Chuisseu, Angèle N. Tchana, Daniela Buonocore and 3 more
Pharmacologia
Gilbert Deccaux Wabo Fotso Kapche, Amadou Dawé, Pierre Waffo‐Téguo, Jean Hubert Donfack, Christian D. Fozing, Dominique Harakat and 5 more
Planta Medica
The chemical investigation of the twigs of Morus mesozygia resulted in the isolation of three new prenylated 2-arylbenzofurans, named moracin KM, LM, and SC (1-3), nine known 2-arylbenzofurans (4-12), and two known flavonoids (13-14). The structures of the new compounds were established as [2'',3'':6,7]-(6-(S)-hydroxymethyl-6-methylpyrano)-2-(3,5-dihydroxyphenyl)benzofuran-5-ol (1), [2'',3'':6,7]-(4,7-dihydro-6-methyloxepine)-2-(3-hydroxy-5-methoxyphenyl)benzofuran-5-ol (2), and [2'',3'':6,7]-(6,6-dimethylpyrano)-2-(3,5-dihydroxyphenyl)benzofuran (3). One of the new compounds, moracin LM (2), displayed modest antioxidant activity, whereas known compounds 4, 13, and 14 showed significant hepatoprotective and antioxidant activities.
Jean Hubert Donfack, Christophe Colombe Fotso Simo, Bathélémy Ngameni, Angèle N. Tchana, Philip G. Kerr, Paola Vita Finzi and 6 more
Natural Product Communications
Free radicals, in particular radical oxygen species (ROS), play an important role in the aetiology and pathogenesis of various diseases. Current research in many countries focuses on the use of local medicinal plants as a promising source of liver protective agents. This paper describes the hepatoprotective effects of the methanol extract and four isolated compounds from Ficus chlamydocarpa on CCl4-induced liver damage, as well as the possible antioxidant mechanisms involved in this protection. The DPPH test, along with the beta-Carotene-Linoleic Acid Model System and Ferric-Reducing Antioxidant Power assays, as well as the inhibition of microsomal lipid peroxidation were used to measure radical-scavenging and antioxidant activities. Pretreatment of rats with the methanol extract of F. chlamydocarpa before CCl4 administration, significantly prevented serum increase of hepatic enzyme markers, glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT), in a dose-dependent manner. The hepatoprotection was also associated with a significant enhancement in hepatic reduced glutathione (GSH) and a marked decrease of liver malondialdehyde (MDA). Among the four compounds 1-4, isolated from the methanol extract, alpha-amyrin acetate (1) and luteolin (4) showed a significant hepatoprotective activity, as indicated by their ability to prevent liver cell death and lactate dehydrogenase (LDH) leakage during CCl4 intoxication.
Faustin Pascal Tsagué Manfo, Paul Fewou Moundipa, H. Déchaud, Ang`le Nkouatchoua Tchana, Edouard Akono Nantia, M. T. Zabot and 1 more
Environmental Toxicology
This study aimed at investigating the effect of agropesticides on male reproductive function in farmers in Djutitsa (West Cameroon). To this end, 47 farmers in Djutitsa were asked questions on their health status and pesticide use in agriculture. Thereafter, their blood samples were collected for assessment of sex hormones including serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), androstenedione, testosterone, as well as sex hormone binding globulin (SHBG). Their serum triiodothyronine (T3) and thyroxine (T4) levels were also measured. Thirty seven men not exposed to agropesticides were recruited as control group. Fifty six pesticides containing 25 active substances were currently used by farmers enrolled in our study, and most of their symptoms were related to spread/use of these chemicals. Compared to the control group, there was no significant difference in FSH, LH, SHBG, estradiol, and thyroid hormones (T3 and T4) levels. Farmers had significantly lower serum testosterone (20.93 ± 1.03 nM vs. 24.32 ± 1.32 nM; P < 0.05) and higher androstenedione level (3.83 ± 0.20 nM vs. 2.80 ± 0.15 nM; P < 0.001). Their serum free testosterone as well as bioavailable testosterone were unchanged, while estradiol/testosterone and androstenedione/testosterone ratios were significantly increased (0.45 ± 0.03% vs. 0.33 ± 0.02%; P < 0.01 and 12.26 ± 3.64 vs 19.31 ± 6.82; P < 0.001, respectively). Our results suggest that male farmers of Djutitsa (West Cameroon) are exposed to agropesticides due to improper protective tool, and this exposure may impair their reproductive function through inhibition of testosterone synthesis; probably by inhibition of testicular 17β- hydroxysteroid dehydrogenase (17HSD3) and induction of aromatase (CYP19).
Frédéric Nico Njayou, Paul Fewou Moundipa, Jean Hubert Donfack, Ddp Chuisseu, A. K. Tchana, B.T. Ngadjui and 1 more
International Journal of Biological and Chemical Sciences
This study aimed at evaluating the in vitro antioxidant and hepatoprotective activities of different stem bark extracts of Erythrina senegalensis prepared with ethanol, and the in vivo hepatoprotective activity and acute toxicity of the best extract. The 2, 4-diphenyl-1-picryl-hydrazil (DPPH) and microsomal lipid peroxidation (MLP) models, and the rat liver slices system were respectively used for the in vitro study. The Methylene chloride/methanol (1:1 v/v) (Emc) and 40% ethanolic (E40) extracts were more efficient in inhibiting MLP and in scavenging DPPH radical. However, E40 was most effective with regards to lactate dehydrogenase (LDH) leakage inhibition from rat liver slices intoxicated with carbon tetrachloride (CCl4). The in vivo hepatoprotective activity was evaluated against CCl4-induced hepatotoxicity in rats. The E40 extract (100 mg/Kg) significantly reduced the increase in ALT, AST and lipid peroxidation in liver homogenate, showing that the extract is as protective as silymarin at the same dose. Acute toxicity was evaluated in mice and E40 did not produce any behavioural changes or mortality even at an oral dose of 16 g/kg. The extract was found to contain antioxidant classes of compounds (flavonoids and polyphenols). In conclusion, the E40 extract of E. senegalensis could be an important source of hepatoprotective compounds.Key words: Erythrina senegalensis, stem bark extract, antioxidant, hepatoprotective, carbon tetrachloride.
Jean Hubert Donfack, Ghislain W. Fotso, B. Ngameni, Florence Tsofack Ngueguim, Abdou Tchoukoua, P. Ambassa and 9 more
亚洲传统医药
The in vitro hepatoprotective effect of the methanolic extract from Irvingia gabonensis (Aubry Lecomte ex O’Rorke) on CCl4induced liver cell damage as well as the possible antioxidant mechanisms involved in this protective effect were investigated. The phytochemical investigation of this methanolic extract led to the isolation of seven compounds identified as: 3-friedelanone (1); betulinic acid (2); oleanolic acid (3); 3, 3’, 4’-tri-O-trimethylellagic acid (4); methyl gallate (5); hardwickiic acid (6) and 3-β-acetoxyursolic acid (7). The hepatoprotective activity of these compounds was tested in vitro against CCl4-induced damage in rat hepatoma cells. Compounds (3), (7), (5) and (2) showed significant hepatoprotective activity as indicated by their ability to prevent liver cell death and LDH leakage during CCl4 intoxication. In addition, 2, 4-dinitrophenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, the β-Carotene-Linoleic Acid Model System (β-CLAMS), the Ferric-Reducing Antioxidant Parameter (FRAP) and microsomal lipid peroxidation assays were used to measure the antioxidant activity of the crude extract and isolated compounds. Compared with compounds (1), (2), (4), and (6), compounds (3), (5) and (7) showed significant antioxidant effects involving radicalscavenging action, inhibition of microsomal lipid peroxidation, β-CLAMS and FRAP assays. These results suggest that the protective effects of the crude extract of Irvingia gabonensis against CCl4-induced hepatotoxicity possibly involve the antioxidant effect of these compounds.
K. Melanie, N. Bilong, Paul Fewou Moundipa
African Journal of Traditional Complementary and Alternative Medicines
Water extracts of Myrnthamnus flabellifolius (shoot) and Ozoroa paniculosa (roots, stem, leaves) and their combinations called “Dankatso” (equal proportion of the above plant extracts) are being used extensively in eastern Botswana traditional medicine. These plants have reputable use as antidiabetic preparations. M. flabellifolius is used to alleviate symptoms of diabetes mellitus, stroke and hypertension. O. paniculosa is used to alleviate menstrual pain and in asthma (Motlhanka, 2008). The study is part of an ongoing project to search for novel drugs from vast array of medicinal plants from Botswana, which have not been studied extensively (Motlhanka et al., 2005), The antioxidant capacity of the extracts together with their combinations was assessed spectrophotometrically using DPPH free radical scavenging assay. At 25 µg/ml the scavenging power of the extracts were as follows: M. flabellifolius alone (66%); O. paniculosa root alone (49%); O. paniculosa stem alone (81%); O. paniculosa leaf alone (79%). At the same concentration (25 µg/ml), combinations: [M. flabellifolius+O. paniculosa root] (85%); [M. flabelllifolius + O. paniculosa stem] (91%); [M. flabellifolius + O. paniculosa leaf] (91%). At 100 µg/ml and above there were no significant differences between scavenging potencies for individual extracts and their combinations (“Dankatso”). The scavenging potencies were in magnitudes of 90-91% for individual extracts and their combinations. This study suggests that the presence of antioxidant compounds in water extracts of the studied plants may be responsible for their anti-diabetic properties as advocated in traditional medicine. Acknowledgements: Traditional healers for supplying the plants. References: Motlhanka D.M et al. (2005) J. of Pharm. & Pharmacol. Vol: 57 S-7. Motlhanka, D.M (2008) Pakistan J of Biol. Sci. Vol:11 (5) 805-808
Edouard Akono Nantia, Paul Fewou Moundipa, Thomas K. Monsees, Serge Carreau
Basic and Clinical Andrology
Abstract For millions of couples, the inability to have a child is a personal tragedy and a large proportion of childless people are confronted with social stigmatization (blame) and personal frustration. Formerly assigned to women, infertility of a couple is nowadays equitably distributed between the two sexes. Among the methods used to treat male infertility problems, medicinal plants have been used empirically as extracts, decoctions, fractions or semi-purified compounds. These herbal products are used in the treatment of a dysfunctioning of the libido, sexual asthenia, erection, and sperm disorders. Pharmacological activities of many of these plants have been shown in vitro using cells, in vivo (on laboratory animals) and human studies. For instance, extracts of Panax ginseng, Panax quinquefolius and Lepidium meyenii have shown positive effects on sexual desire; while extracts of Astragalus membranaceus, Asparagus racemous, Withania somnifera, Andrographis paniculata and Acanthopanax senticosus improved sperm parameters. Plants provide a treatment option that is affordable and available for infertile couples, and phytotherapy is an essential form of treatment in our health system. However, herbal products are still anarchically used in many regions and countries, and a great proportion of medicinal plants used traditionally to solve male reproductive disorders have not yet been scientifically evaluated. Therefore in this review, we have summarized most of the data dealing with the effects of plant extracts on mammalian reproductive functions.
Gilbert Deccaux Wabo Fotso Kapche, Christian D. Fozing, Jean Hubert Donfack, Ghislain W. Fotso, Amadou Dawé, Angèle N. Tchana and 4 more
Phytochemistry
DA Zock, NE Moukouri, Christophe Nouedoui, MF Etongue, Paul Fewou Moundipa, P. H. Amvam Zollo and 2 more
clinics in Mother and Child Health
Ce travail a pour but de determiner le profil des hormones thyroidiennes chez des femmes enceintes en milieu Camerounais. De Janvier 2005 a Janvier 2006, cent vingt cinq femmes ont ete prospectivement incluses dans l\'etude a l\'Hopital General de Yaounde. Pour chaque patiente, selon un protocole preetabli, on recueillait les donnees cliniques et Gyneco-Obstetrique avec l\'âge de la grossesse, et on faisait un prelevement sanguin en vu du dosage des hormones thyroidiennes (thyroide T4 et triiodothyronine T3) et de la thyreostimuline hypophysaire (TSH). La lecture des resultats des taux hormonaux a ete effectuee a l\'aide d\'un compteur Gamma 12 puis d\' «Oakfield Health Care Product» muni de Logiciel RIASTAT d\' «Oakfield Instrument Ltd» London. Les 125 femmes de l\'etude ont ete reparties en quatre groupes composes respectivement de 32 femmes non gravides (groupe I, temoins), 33 femmes enceintes au premier trimestre (groupe II), 30 femmes au deuxieme trimestre (groupe III), et 30 femmes enceintes a la grossesse du troisieme trimestre (groupe IV). Le taux moyen de la T4 comme de la T3 sanguin est plus eleve chez les femmes enceintes que chez les temoins quelque soit l\'âge de la grossesse. L\'evolution des taux montre une elevation au premier trimestre de la grossesse avec une baisse au deuxieme trimestre et au troisieme. Le taux de la TSH hypophysaire a une cinetique contraire avec un effondrement au premier trimestre et une remontee au deuxieme et troisieme trimestre. En conclusion, ce travail montre qu\'il y a une variation du taux sanguin des hormones thyroidiennes et de la TSH chez la femme enceinte et que ce taux varie avec l\'âge de la grossesse. This study was aimed at determining the evolution and the kinetics of thyroid hormones in a sub-population of pregnant women in Cameroon. We carried out a prospective study (from January 2005 to January 2006) on 125 consenting pregnant women at the Yaounde General Hospital. Clinical and gynaeco-obstetric data with the gestational age were noted on a pre-designed questionnaire. Blood samples were drawn for serum assay of thyroxine (T4), triiodothyronine (T3) and thyroid stimulating hormone(TSH). The results were read with the «Oakfield Health Care» Gamma – 12 counter using the RIASTAT software. The patients were sub divided into 4 groups: 32 non pregnant women in the control group, 33 pregnant women in the first trimester, 30 pregnant women in the second trimester, and 30 pregnant women in the third trimester. The mean serum levels of T3 and T4 were relatively high in all the pregnant women (irrespective of the gestational age) than in the control group. Serum levels of T3 and T4 were raised the first trimester and progressively reduced in second and third. On the other hand, TSH levels progressively increased from the second trimester and attained a maximum in the third trimester. We can therefore conclude that blood levels of thyroid hormone as well as TSH vary during pregnancy and differ in titres with respect to the gestational age. Keywords : Thyroid hormones - TSH - Pregnancy - Radio immunoassay. Clinics in Mother and Child Health Vol. 5 (2) 2008: pp. 917-920
Paul Fewou Moundipa, Kamini G. Melanie Flore, Charles Félix Bilong Bilong, Iris Bruchhau
TSpace (University of Toronto)
Fifty five medicinal plants belonging to different families selected on \nthe basis of their traditional use against jaundice and various liver \ndisorders were tested for their amoebicidal activities. They were \nextracted and tested for their antiamoebic activity in vitro using \npolyxenic culture of Entamoebic histolytica . As the result, 14 \nexhibited an antiamoebic activity at a dose of 100μg/ml from the \nsecond to the fourth day of incubation. The 14 extracts selected \nextracts were additionnaly tested for 6 days at 10, 100 and \n500μg/ml of concentration, and only the leaves extract of Codiaeum \nvariegatum exhibited a clear antiamoebic activity (EC50=10,74 \nthe second day), and had a more pronounced activity than metronidazole \nthe reference product.
Frédéric Nico Njayou, Paul Fewou Moundipa, Angèle N. Tchana, Félicité Mbiapo Tchouanguep
Journal of the Cameroon academy of sciences
PB Telefo, MT Rubio Pellicer, Paul Fewou Moundipa, M. F. Tchouanguep, B. Malpaux, C Tchouanguep
HAL (Le Centre pour la Communication Scientifique Directe)
International audience
Phélix Bruno Téléfo, Paul Fewou Moundipa, Félicité Mbiapo Tchouanguep
Journal of Ethnopharmacology
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