Hepato-protective, antioxidant activities and acute toxicity of a stem bark extract of Erythrina senegalensis DC.

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

Human Immunodeficiency Virus and Hepatitis C Virus Co-infection in Cameroon: Investigation of the Genetic Diversity and Virulent Circulating Strains

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 HIVmono-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

Hepatoprotective and antioxidant activities of stem bark extract of Khaya grandifoliola (Welw) CDC and Entada africana Guill. et Perr

ABSTRACT Khaya grandifoliola (Meliaceae) and Entada africana (Fabaceae) are traditionally used as source of medicines against liver related diseases. But the most efficient solvent to extract the plants bioactive compounds has not yet been found. This work aimed at evaluating and comparing the hepatoprotective 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 lactate dehydrogenase (LDH) leakage as toxicity marker. The antioxidant activity was assessed by using 2, 4-diphenyl-1-picryl-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 tested 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 antioxidant study, the MCME and WE extracts of both plants performed well in inhibiting 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 compounds including polyphenols were tested positive in the MCME extracts. From the interesting activity of these extracts, it might be concluded that methylenechloride-methanol (1:1v/v) mixture is the most efficient solvent to extract hepatoprotective and antioxidant active principles from K. grandifoliola and E. africana stem bark

A new transmission risk index for human African trypanosomiasis and its application in the identification of sites of high transmission of sleeping sickness in the Fontem focus of southwest Cameroon

A new index for the risk for transmission of human African trypanosomiasis was developed from an earlier index by adding terms for the proportion of tsetse infected with Trypanosoma brucei gambiense group 1 and the contribution of animals to tsetse diet. The validity of the new index was then assessed in the Fontem focus of southwest Cameroon. Averages of 0.66 and 4.85 Glossina palpalis palpalis (Diptera: Glossinidae) were caught per trap/day at the end of one rainy season (November) and the start of the next (April), respectively. Of 1596 tsetse flies examined, 4.7% were positive for Trypanosoma brucei s.l. midgut infections and 0.6% for T. b. gambiense group 1. Among 184 bloodmeals identified, 55.1% were from pigs, 25.2% from humans, 17.6% from wild animals and 1.2% from goats. Of the meals taken from humans, 81.5% were taken at sites distant from pigsties. At the end of the rainy season, catches were low and similar between biotopes distant from and close to pigsties, but the risk for transmission was greatest at sites distant from the sties, suggesting that the presence of pigs reduced the risk to humans. At the beginning of the rainy season, catches of tsetse and risk for transmission were greatest close to the sties. In all seasons, there was a strong correlation between the old and new indices, suggesting that both can be used to estimate the level of transmission, but as the new index is the more comprehensive, it may be more accurate

Effect of methanol extract of Basella alba L. (Basellaceae) on the fecundity and testosterone level in male rats exposed to flutamide in utero

International audienceWe 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

BASELLA ALBA (BASELLACEAE) AND MALE REPRODUCTIVE FUNCTION

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 (

Profil Des Hormones Thyroidiennes Chez Les Femmes Enceintes: Analyse de 125 cas a l\'Hôpital Général de Yaoundé, Cameroun

Ce travail a pour but de déterminer le profil des hormones thyroïdiennes chez des femmes enceintes en milieu Camerounais. De Janvier 2005 à Janvier 2006, cent vingt cinq femmes ont été prospectivement incluses dans l\'étude à l\'Hôpital Général de Yaoundé. Pour chaque patiente, selon un protocole préétabli, on recueillait les données cliniques et Gynéco-Obstétrique avec l\'âge de la grossesse, et on faisait un prélèvement sanguin en vu du dosage des hormones thyroïdiennes (thyroïde T4 et triiodothyronine T3) et de la thyréostimuline hypophysaire (TSH). La lecture des résultats des taux hormonaux a été effectuée à 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\'étude ont été reparties en quatre groupes composés respectivement de 32 femmes non gravides (groupe I, témoins), 33 femmes enceintes au premier trimestre (groupe II), 30 femmes au deuxième trimestre (groupe III), et 30 femmes enceintes à la grossesse du troisième trimestre (groupe IV). Le taux moyen de la T4 comme de la T3 sanguin est plus élevé chez les femmes enceintes que chez les témoins quelque soit l\'âge de la grossesse. L\'évolution des taux montre une élévation au premier trimestre de la grossesse avec une baisse au deuxième trimestre et au troisième. Le taux de la TSH hypophysaire a une cinétique contraire avec un effondrement au premier trimestre et une remontée au deuxième et troisième trimestre. En conclusion, ce travail montre qu\'il y a une variation du taux sanguin des hormones thyroïdiennes 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. 917-92

ANTIFUNGAL COMPOUNDS ISOLATED FROM DIOSPYROS BIPINDENSIS

Diospyros bipindensis (Gürke) stem barks are used in Cameroon by pygmies Baka for the treatment of pulmonary diseases. One hypothesis was that this type of diseases could be caused by fungi. Thus the antifungal activity of the traditional preparation as well as that of different extracts was tested against Candida albicans. Some extracts presented a significant antifungal activity. The bioguided isolation was undertaken using HPLC-microfractionation in 96 well plates combined with bioautography in order to localize the active compounds in the HPLC profiling of the extracts. In a second step, medium pressure chromatography was used to isolate the active compounds. Using this approach seventeen compounds were isolated, nine of them are new natural products. The structures of the isolated compounds were elucidated by classical spectroscopic methods including UV, NMR and HR-MS