Hepatoprotective effects of Vernonia amygdalina (astereaceae) in rats treated with carbon tetrachloride.

The possible modulatory effect of methanolic extract of Vernonia amygdalina (MEVA), a plant widely consumed in the tropics and used locally in the treatment of fever, jaundice, stomach disorders and diabetes on the toxicity of CCl(4), was investigated in male rats. Oral administration of CCl(4) at a dose of 1.2g/kg body weight 3 times a week for 3 weeks significantly induced marked hepatic injury as revealed by increased activity of the serum enzymes ALT, AST, SALP and gamma-GT. Methanolic extract of V. amygdalina administered 5 times a week for 2 weeks before CCl(4) treatment at 250 and 500 mg/kg doses of the extract ameliorated the increase in the activities of these enzymes. Likewise the methanolic extract of V. amygdalina reduced the CCl(4)-induced increase in the concentrations of cholesterol, triglyceride and phospholipid by 37.8%, 30.6% and 8.5%, respectively, and a reduction in the cholesterol/phospholipids ratio. These parameters were however increased at 750 mg/kg extract pretreatment. CCl(4)-induced lipid peroxidation was likewise attenuated by 57.2% at 500 mg/kg dose of the methanolic extract of V. amygdalina. Similarly, administration of the extract increased the activities of the antioxidant enzymes: superoxide dismutase, glutathione S-transferase and reduced glutathione concentration significantly at 500 mg/kg (P<0.05) and catalase activity at 500-1000 mg/kg doses. These results suggest that methanolic extract of V. amygdalina leaves posseses protective effect against CCl(4)-induced hepatotoxicity by the antioxidant mechanism of action.