Antithrombotic potential of grape juice and red wine for preventing heart attacks

Epidemiologic studies have shown an inverse col relation between the intake of dietary flavonoids and death from coronary artery disease. This is often attributed to the antioxidant properties of flavonoids found in wine and other fruit beverages. We have previously shown that the flavonoids in red but not white wine and purple grape juice significantly inhibit in vivo platelet activity in a canine model of arterial stenosis with intimal damage and periodic thrombosis. We then tested the platelet inhibitory effects of red and white wine and purple grape juice in 10 healthy human subjects. Blood samples were obtained for whole blood aggregometry before and after each fasting subject consumed 5 ml/kg of either a French red wine, French white wine, or 12 mg/kg of purple grape juice. There was a 7-day washout period between consumption of each beverage. In the 10 subjects, whole blood platelet aggregation in response to collagen decreased by 39 +/- 11% (p < 0.01) and by 28 +/- 106% (p < 0.05) in response to ADP after the red wine but there were no significant changes after the white wine. Blood alcohol content averaged 0.06 g/dl after both wines. The purple grape juice decreased collagen-induced platelet aggregation by 34 +/- 11% (p < 0.03) and ADP-induced aggregation by 24 +/- 12% (p < 0.05). Many of the same polyphenolic compounds occur in wine and purple grape juice although there are significantly more of these compounds in red wine and purple grape than in white wine. Red wine and purple grape juice also have significantly higher amounts of antioxidant substances than white wine. It may be that the antiplatelet/antioxidant polyphenolic compounds in red wine or purple grape juice can reduce the rate of progression of the atherosclerotic process, and reduce the incidence of acute occlusive platelet mediated coronary thrombosis.