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The endothelial cells' dysfunction linked to the development of atherosclerosis plays an important role in the regulation of inflammatory responses. Previous studies demonstrated the antiatherogenic effects of Garcinia kola seed extracts based on their lipid lowering effects. Our recent studies showed the in vitro antioxidant and anti-inflammatory activities of the ethanolic extract of Garcinia kola stem barks (EE). For more insight on the antiatherogenic effect of EE, we investigated its activity on some key points of the atherosclerosis process. The cytotoxicity of EE as well as its effects on LDL-uptake, LPS-induced InterCellular Adhesion Molecule (ICAM-1) and Annexin-1 (Anxa-1) expression and LPSinduced DNA damage were evaluated in Human Umbilical Vein Endothelial Cells (HUVECs). EE significantly (p<0.0001) increased the cell viability in both naive and LPS-treated HUVECs. At the concentrations of 50 and 100 µg/ml, EE significantly reduced LDL-uptake by endothelial cells stimulated with LPS. The immunohistochemistry results showed a significant (p<0.01) decrease in the ICAM-1 expression at the EE concentration of 250 µg/ml. EE also showed a significant (p<0.0001) concentration-dependent reduction of Annexin-1 expression in LPS-treated HUVECs. Besides, EE exhibited significant inhibition on LPS-induced genotoxicity marked by a decrease in tail DNA expression (p<0.0001) and tail movement expression (p<0.001) for the concentrations of 50 and 100 µg/ml. These findings showed that EE may mitigate the atherogenic process by reducing LDL-uptake and the expression of adhesion molecules. Thus, the EE of Garcinia kola turns out to be a potential candidate for the treatment of atherosclerosis with a lower risk of toxicity. [ABSTRACT FROM AUTHOR]

Background: Stephania abyssinica (Dillon & A. Rich) Walp (Menispermaceae) is a medicinal plant used in the west region of Cameroon to treat arterial hypertension. The present study evaluated the vasorelaxant effects of the aqueous (AESA) and methanol (MESA) extracts from the fresh leaves of S. abyssinica on aorta rings isolated from Wistar rats. Methods: Aorta rings with intact endothelium were contracted with KCl (60 mM) or phenylephrine (10−5 M) and exposed to cumulative concentrations of each extract, ranging from 10 to 1,000 µg/mL. The vasorelaxant effects of AESA were further evaluated in presence of Nω-nitro-L-arginine methyl ester ( L-NAME, 10−4 M), tetraethylammonium (TEA, 5 µM), glibenclamide (5 µM), propranolol (5 µM), and the association glibenclamide-propranolol (AGP). In another set of experiments, the effect of AESA was evaluated on calcium-induced contraction in a hyperpotassic milieu. Results: AESA and MESA exhibited a concentration-dependent vasorelaxation on KCl-contracted aortic rings with respective EC50 of 160.10 and 346.50 µg/mL. AESA similarly relaxed aortic rings contracted with phenylephrine (EC50, 176.80 µg/mL). The vasorelaxant activity of AESA was not significantly affected by L-NAME but was markedly reduced by TEA, glibenclamide, propranolol, and AGP. AESA strongly inhibited the Ca2+-induced contraction by 95%. Conclusions: These results support the use of S. abyssinica against arterial hypertension and suggest that the vasorelaxant effect of AESA is not mediated via the endothelium/nitric oxide pathway. AESA relaxant properties might be due to an inhibition of Ca2+ influx and/or the activation of ATP-sensitive K+ channels probably via the stimulation of β-adrenergic receptors. [ABSTRACT FROM AUTHOR]

This study evaluates the vasorelaxant and antihypertensive effects of the aqueous extract from the stem bark of M. africana (AEMA). AEMA was tested in vitro on intact or endothelium-denuded rats' aorta rings precontracted with KCl or norepinephrine in absence or in presence of L-NA ME or glibenclamide. The effect of a single concentration (300 μg/mL) of AEMA was also examined on the concentration-response curve of KCl. In vivo, the antihypertensive effects of AEMA (200 mg/kg/day) were evaluated in maleWistar rats treated with L-NA ME (40mg/kg/day) for 4 weeks. AEMA relaxed aorta rings precontracted with NE or KCl with respective EC50 values of 0.36 μg/mL and 197.60 μg/mL. The destruction of endothelium or pretreatment of aorta rings with L-NA ME shifted the EC50 of AEMA from 0.36 μg/mL to 40.65 μg/mL and 20.20 μg/mL, respectively. The vasorelaxant activity of M. africana was significantly inhibited in presence of glibenclamide. AEMA also significantly inhibited the concentrationresponse curve of KCl. Administered orally, AEMA induced acute and chronic antihypertensive effects and normalized renal NO level. These results show that the vasorelaxant activity of AEMA might be mediated by the activation of the NO-cG MP-ATPdependent potassium channels pathway and might predominantly account for its antihypertensive effect. [ABSTRACT FROM AUTHOR]

The aqueous, hexane, acetone, and methanol extracts of the stem bark of Anthocleista vogelii Planch. (Loganiaceae) were screened for antiulcerogenic activity using HCl/ethanol gastric necrotizing solution. The methanol extract showed 100% inhibition at a dose of 500 mg/kg compared with the aqueous, hexane, and acetone extracts, which produced 87.91%, 61.39%, and 76.89%, respectively. The methanol and aqueous extracts were further tested against ulceration induced by indomethacin (30 mg/kg) and pylorus ligation at doses of 125, 250, and 500 mg/kg. The aqueous extract at a dose of 500 mg/kg significantly (p ≤ 0.01) reduced indomethacin-induced gastric lesions by 78.62% while the methanol extract at the same dose completely inhibited the action of indomethacin. The aqueous extract of A. vogelii at doses of 250 and 500 mg/kg induced a decrease of about 15% and 40%, respectively, of the surface area in the pylorus-ligated rats. Similarly, the methanol extract at doses 250 and 500 mg/kg produced a decrease of almost 25% and 70%, respectively. The gastric juice secretion increased significantly (p ≤ 0.05) at a dose of 500 mg/kg in the aqueous extract while the gastric acidity significantly (p ≤ 0.01) decreased at doses of 125 and 500 mg/kg in aqueous and methanol extracts as compared with the control group. These findings show that the aqueous and organic extracts of the stem bark of Anthocleista vogelii possess potent antiulcer properties thereby lending support to the ethnomedical uses of the plant in the treatment of stomachache. [ABSTRACT FROM AUTHOR]

Introduction: the paucity of data on hepatitis' epidemiology in Menoua Division, west region, Cameroon, prompted us to assess the prevalence of viral and non-viral hepatitis in this area. Methods: a retrospective exhaustive study based on records of patients from January 2008 to June 2014 was conducted in 9 health centres in Menoua Division. Targeted subjects were patients who did not receive hepatitis vaccines for the past year and have been screened for hepatitis B virus (HBV), hepatitis C virus (HCV) and/or a blood transaminase. Associations between variables were quantified with odd ratios (OR) and 95% confidence interval (CI). Cochran-Armitage test of linear trend was used for testing proportions of ordinal variables. Fisher's exact test was used for testing the association between 2 qualitative variables when expected counts were less than 5. Results: the overall prevalence were 9.6% and 6.7% for HBV and HCV respectively. HBV mostly infected people aged 21-30 (12.4%) while the prevalence of HCV increased with age up to 35.4% (p=0.03). A 0.6% co-infection was observed. Thirty percent of positive HBV or HCV had high transaminase while 13% of patients with elevated transaminase showed negative viral serology. Conclusion: these results show that hospital-based prevalence of HCV and HBV in Menoua Division is under the Cameroon's national range but point out the fact that non-viral hepatitis might be a serious case of concern in this area. There is therefore, a need to identify the risk-factors of non-viral hepatitis. [ABSTRACT FROM AUTHOR]