Further evidence for zinc as a hepatoprotective agent in rat liver toxicity.

The present study was envisaged to investigate the protective effects of zinc treatment on the activities of various drug metabolizing enzymes, reduced glutathione content, and extent of lipid peroxidation in the livers of male albino rats subjected to long-term carbontetrachloride (CCl4) toxicity. It was observed that the activities of cytochrome P450, cytochrome b5, NADPH-cytochrome-c-reductase, and glutathione concentrations were significantly depressed following treatment with CCl4 for 6 weeks. At the same time, a marked elevation was seen in the extent of NADPH-dependent lipid peroxidation after CCl4 toxicity. Moreover, significantly depressed concentrations of zinc (Zn2+) were observed in both serum and liver after 6 weeks of the CCl4 administration. However, simultaneous zinc treatment to CCl4-intoxicated rats resulted in significant improvement in the activities of most of the drug metabolizing enzymes as well as the glutathione levels. Similarly, zinc treatment also normalized the CCl4-induced increase in the extent of NADPH-dependent lipid peroxidation. We conclude that zinc supplementation considerably attenuates the liver injury induced by chronic CCl4 treatment to rats.