Effects of Antioxidant Nutrient Supplementation on the Lipid Peroxidation and Antioxidative Enzyme Activities in Patients with Coronary Heart Disease

This study was carried out to evaluate whether antioxidant nutrient suppplementation with $\alpha$-tocopherol, vitamin C, $\beta$-carotene, and selenium reduces the lipid peroxide levels and increases the antioxidative enzyme activities in patients with coronary hart disease. Eighty nine patients participated in a randomized, double-blind, placebo-controlled trial. The antioxidant group (45 patients) was given daily doses of $\alpha$-tocopherol (400 IU), vitamin C (50 mg), $\beta$-carotene (15 mg), and selenium (50 $\mu\textrm{g}$) and forty four patients received a placebo. Thirty eight subjects (84.4%) of the antioxidant group and thirty nine subjects (88.6%) of the placebo group completed the three-month supplementation. Serum levels of tocopherol, vitamin C and $\beta$-carotene significantly increased in the antioxidant group compared with the baseline (p<0.05). Thiobarbituric acid-reactive substances(TBARS) decreased significantly (0.6 nmol MDA/mL) in the antioxidant group compared with that (0.09 nmol MDA/mL) in the placebo group (p=0.03). However, antioxidant supplementation did not affect the level of oxidized-LDL measured as autoantibodies against oxidized-LDL. The superoxide dimutase activity in red blood cells increased in the antioxidant group compared with the baseline (p<0.05). However, glutathione peroxidase activities did not change after supplementation in both groups, and catalase activity significantly decreased in the placebo group (p<0.05). These results suggest that antioxidant supplementation for 3 months with $\alpha$-tocopherol, vitamin C, $\beta$-carotene and selenium in patients with coronary heat disease may be partially protective against oxidative stress.