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 TXB(2)/2,3 dinor 6 keto PGF(1alpha) ratio, a marker of the pathogenesis of thrombosis and arteriosclerosis.

METHODS

This study was a randomised, double-blind, placebo-controlled 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-dehydro TXB(2) and 2,3 dinor 6 keto PGF(1alpha) 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 TXB(2)/2,3 dinor 6 keto PGF(1alpha) 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 TXB(2)/2,3 dinor 6 keto PGF(1alpha) 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.