Wu Chin-Chung, Wu Chung-I, Wang Wei-Ya, Wu Yang-Chang
Graduate Institute of Nature Products, Kaohsiung Medical University, Kaohsiung City, Taiwan, ROC.
Planta Med. 2007 May;73(5):439-43. doi: 10.1055/s-2007-967173.
Resveratrol, a polyphenolic compound found in grapes and other fruits, is thought to contribute to the cardioprotective effect of red wine. While resveratrol exhibits some antiplatelet effect in vitro, the concentrations needed are much higher than those in plasma after consumption of red wine. In the present study, we investigate if resveratrol is able to potentiate the effect of endogenous antiplatelet substances--prostaglandin (PG) I2 and PGE1. In human platelet suspension resveratrol at relatively low concentrations (2 or 5 microM), which did not affect platelet function, significantly enhanced the inhibitory activity of PGs on platelet aggregation caused by collagen. The mechanisms underlying this effect may be associated with the inhibition of protein kinase C activation and protein tyrosine phosphorylation, but not with cyclic nucleotide levels and intracellular calcium mobilization in platelets. Our results might provide a possible explanation for the in vivo antiplatelet effect of resveratrol despite the poor bioavailability and the weak in vitro activity.
白藜芦醇是一种存在于葡萄和其他水果中的多酚类化合物，被认为对红酒的心脏保护作用有贡献。虽然白藜芦醇在体外表现出一定的抗血小板作用，但所需浓度远高于饮用红酒后血浆中的浓度。在本研究中，我们探究白藜芦醇是否能够增强内源性抗血小板物质——前列腺素（PG）I2和PGE1的作用。在人血小板悬液中，相对低浓度（2或5微摩尔）的白藜芦醇不影响血小板功能，但能显著增强PGs对胶原蛋白引起的血小板聚集的抑制活性。这种作用的潜在机制可能与抑制蛋白激酶C活化和蛋白酪氨酸磷酸化有关，而与血小板中的环核苷酸水平和细胞内钙动员无关。尽管白藜芦醇的生物利用度差且体外活性弱，但我们的结果可能为其体内抗血小板作用提供一种可能的解释。
