Effects of de.alcoholated red wine and its phenolic fractions on platelet aggregation.

Background and Aim: Platelet aggregation is involved in atherosclerosis and pharmacological inhibition of platelet activity may reduce the risk of coronary thrombosis and myocardial infarction. Red wine polyphenols may reduce platelet aggregability. This study evaluates the effect of de-alcoholated red wine (DRW) and its phenolic fractions on rat platelet aggregation and cyclic AMP (c-AMP) content. Methods and Results: DRW was fractionated into four classes of phenolic compounds: phenolic acids (fraction 1), procyanidins, catechins and monomeric anthocyanidins (fraction 2), flavonols and resveratrol (fraction 3) and polymeric anthocyanidins (fraction 4). The effect of each fraction on ADP-induced rat platelet aggregation and c-AMP content was compared with that of DRW and pure phenolic compounds (quercetin, catechin, resveratrol, caffeic acid). DRW completely inhibited ADP-induced platelet aggregation. Fraction 2 also showed a significant anti-aggregating activity, whereas the effects of fractions 3 and 4 and the pure phenolics were not significant. A significant increase in platelet c-AMP content was observed after the addition of DRW and fraction 2. Conclusions: Our data indicate that DRW and its catechin-anthocyanidin fraction exert a significant effect on platelet aggregation in vitro, perhaps by enhancing platelet c-AMP levels.