Abstract
Purpose: To investigate the modulating effects of ascorbic acid (AA) and/or f -tocopherol (AT) at various doses in the generation of hepatic lipid peroxidation (LPO) and the antioxidant defence system in normal Balb/c mice. Design: Biochemical investigations in supplemented vs control laboratory animals. Materials and Methods: The various groups of animals were fed orally different doses of AA (2 or 50 mg/100 gm b.wt), AT (5 or 35 I.U./kg b.wt) or both AA and AT (2 mg/100 gm b.wt + 5 I.U./kg b.wt or 50 mg AA/100 gm b.wt + 35 I.U. AT/kg b.wt respectively) for 8 weeks. Various antioxidant enzymes, glutathione (GSH) and LPO levels were estimated spectrophotometrically in the livers. Results: The results showed a significant decline in LPO in all the treated groups except for the group which received 50 mg AA/100 gm b.wt. The decline in LPO was significant in the groups of animals treated with both AA and AT revealing their synergistic effects. Glutathione content in the hepatic tissue increased in all groups except for the group which received 2 mg AA/100 gm b.wt. Liver glutathione reductase (GR) increased in all the treated groups as compared to their controls. Cu-Zn superoxide dismutase (SOD) activity increased significantly in all the treated groups except for the group treated with 2 mg AA/100 gm b.wt or 5 I.U.AT/kg b.wt. At lower doses of AA or AT, liver glutathione peroxidase (GSH-Px) showed a significant decrease while at higher doses of AA + AT a significant increase in GSH-Px activity was observed. Catalase activity in the liver remained unchanged in all the groups studied. Conclusion: The study indicates that the combination of AA and AT at the lower dose is quite effective in combating oxidative stress in the liver.