beta-carotene and Thrombosis

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.. 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.. 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.. 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.

Topics: 6-Ketoprostaglandin F1 alpha; Antioxidants; Arteriosclerosis; beta Carotene; Biomarkers; Dietary Supplements; Dose-Response Relationship, Drug; Double-Blind Method; Female; Humans; Male; Middle Aged; Patient Compliance; Platelet Activation; Prostaglandins I; Selenium; Thrombosis; Thromboxane B2; Thromboxanes; Trace Elements; Vitamins; Zinc

Recent data have shown an association between polymorphisms of prostaglandin-endoperoxide synthase-2 gene (PTGS2; alias COX-2), and prostaglandin-E receptor-2 gene (PTGER2) and risk of atherothrombotic disorders.. We evaluated two PTGS2 (rs20417, rs689470), and three PTGER2 (rs708494/uS5, rs708495/uS7, and chr14: 50 764 013/uS10) gene polymorphisms among 600 Caucasian male participants of the Physicians' Health Study with incident myocardial infarction (MI) or ischemic stroke and 600 age- and smoking-matched controls who remained free of all reported cardiovascular disease.. Genotype distributions were in Hardy-Weinberg equilibrium in the control groups. Genotype and allele distribution were similar between cases and controls. The polymorphisms tested were in linkage disequilibrium. Results from the adjusted haplotype-based conditional logistic regression analysis showed a modest association of the PTGER2 2-1-1 haplotype with reduced risk of MI (odds ratio = 0.50, 95% CI; CI = 0.26-0.97, P = 0.04), and the 2-2-1 haplotype with reduced risk of ischemic stroke (odds ratio = 0.68, 95% CI = 0.47-0.99, P = 0.048). In contrast to prior data, we found no evidence for an association of the PTGS2 polymorphisms/haplotypes tested with risk of incident MI nor with ischemic stroke. However, we found suggestive evidence for an association of specific PTGER2 haplotypes with reduced risk of these outcomes.. Although these prospective data implicate the potential involvement of prostaglandin-E receptor-2 gene variation in atherothrombosis, external validation of our findings is needed.

Topics: Adult; Aged; Aged, 80 and over; Aspirin; beta Carotene; C-Reactive Protein; Case-Control Studies; Cyclooxygenase 2; Double-Blind Method; Female; Genotype; Humans; Male; Membrane Proteins; Middle Aged; Placebos; Polymorphism, Genetic; Receptors, Prostaglandin E; Thrombosis