Effects of dietary vitamin E, C and soybean oil supplementation on antioxidant enzyme activities in liver and muscles of rats

The effect of elevated levels of dietary vitamin E, C and a combination of vitamin E and C (E & C) with soybean oil on activities of antioxidant (AOE) enzymes important in the protection against lipid peroxidation was studied in male rats fed with vitamin C (12 mg/g), vitamin E (3.68 mg/g) or E & C (3.68 mg/kg + 12 mg/g) supplemented diets for 28 days. Catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) activity in liver, pectoralis major (PM) and sartorius (S) muscles was increased significantly in rats fed with dietary vitamin C, E separately, and vitamin C & E combination, except, superoxide dismutase (SOD), which showed no alterations. These results clearly indicated that vitamin E & C separately and E & C together increased AOE activity in liver, PM and S muscle of rats. However, vitamin E and C combination enhanced AOE activity more significantly and our findings suggest the possible role of vitamin C & E and their combination in reducing the risk of chronic diseases related to oxidative stress.