Complex effects of different green tea catechins on human platelets

FEBS Letters

Weber, Artur-Aron¹  Schrör, Karsten¹  Voit, Simone¹  Lill, Gereon¹ 

[1] Institut für Pharmakologie und Klinische Pharmakologie, Universitätsklinikum Düsseldorf, Moorenstr. 5, D-40225 Düsseldorf, Germany

关键词: Green tea;    Catechin;    Epigallocatechin gallate;    Platelet;    Aggregation;   

DOI  :  10.1016/S0014-5793(03)00599-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Epigallocatechin gallate (EGCG), a major component of green tea, has been previously shown to inhibit platelet aggregation. The effects of other green tea catechins on platelet function are not known. Pre-incubation with EGCG concentration-dependently inhibited thrombin-induced aggregation and phosphorylation of p38 mitogen-activated protein kinase and extracellular signal-regulated kinases-1/2. In contrast EGCG stimulated tyrosine phosphorylation of platelet proteins, including Syk and SLP-76 but inhibited phosphorylation of focal adhesion kinase. Other catechins did not inhibit platelet aggregation. Interestingly, when EGCG was added to stirred platelets, a tyrosine kinase-dependent stimulation of platelet aggregation was observed. The two other catechins containing a galloyl group in the 3′ position (catechin gallate, epicatechin gallate) also stimulated platelet aggregation, while catechins without a galloyl group (catechin, epicatechin) or the catechin with a galloyl group in the 2′ position (epigallocatechin) did not.

【 授权许可】

Unknown