Hepatoprotective effect of aqueous extract of Aframomum melegueta on ethanol-induced toxicity in rats.

Nutritional and Industrial Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria.
Acta biochimica Polonica (Impact Factor: 1.19). 08/2011; 58(3):355-8.
Source: PubMed

ABSTRACT In recent years there have been remarkable developments in the prevention of diseases, especially with regards to the role of free radicals and antioxidants. Ethanol-induced oxidative stress appears to be one mechanism by which ethanol causes liver injury. The protective effect of aqueous plant extract of Aframomum melegueta on ethanol-induced toxicity was investigated in male Wistar rats. The rats were treated with 45 % ethanol (4.8 g/kg b.w.t.) for 16 days to induce alcoholic diseases in the liver. The activities of alanine aminotransferase, aspartate aminotransferase and triglyceride were monitored and the histological changes in liver examined in order to evaluate the protective effects of the plant extract. Hepatic malondialdehyde and reduced glutathione, as well as superoxide dismutase and glutathione-S-transferase activities were determined for the antioxidant status. Chronic ethanol administration resulted in a statistically significant elevation of serum alanine aminotransferases and triglyceride levels, as well as a decrease in reduced glutathione and superoxide dismutase which was dramatically attenuated by the co-administration of the plant extract. Histological changes were related to these indices. Co-administration of the plant extract suppressed the elevation of lipid peroxidation, restored the reduced glutathion, and enhanced the superoxide dismutase activity. These results highlight the ability of Aframomum melegueta to ameliorate oxidative damage in the liver and the observed effects are associated with its antioxidant activities.

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