Effect of low dose antioxidant vitamin and trace element supplementation on the urinary concentrations of thromboxane and prostacyclin metabolites

Objective: This trial evaluated the effect of antioxidant supplementation on the urinary excretion of 11-dehydro TXB2/2,3 dinor 6 keto PGF(1 alpha) ratio, a marker of the pathogenesis of thrombosis and arteriosclerosis. Methods: This study was a randomised, double-blind, placebo-coninolled trial involving 186 presumably healthy volunteers. One hundred received a multi-antioxidant supplementation and 86 a placebo for two years. Blood zinc, selenium, beta-carotene, vitamin C and E and urinary excretion of 11-dehydroTXB(2) and 2,3 dinor 6 keto PGF(1)alpha were measured. Results: Baseline subject characteristics did not differ between the two groups. Blood zinc, selenium, and beta-carotene concentrations significantly increased between baseline and two years in the multi-antioxidant supplementation group supporting subject compliance (p < 0.05). At two years, the median urinary 11-dehydro TXB2/2,3 dinor 6 keto PGF(1 alpha) ratio was significantly lower in the multi-antioxidant supplementation group (3.4 versus 2.78, p = 0.015). Serum selenium concentration was the only antioxidant studied that was significantly related to the urinary 11-dehydro TXB2/2,3 dinor 6 keto PGF(1)alpha ratio. Conclusions: These results support the hypothesis that a low-dose multi-antioxidant supplementation may contributes to a reduction in platelet activation which is beneficial for cardiovascular function.