title: Platelet aggregation induced by the C-terminal peptide of thrombospondin-1 (4N1-1) is inhibited by epigallocatechin gallate but not by prostaglandin E1.
abstract: The C-terminal peptide of thrombospondin (4N1-1) stimulates distinct signalling pathways but induces an activation-independent platelet aggregation. This study demonstrates inhibitory effects of epigallocatechin gallate (EGCG), a major flavonoid component of green tea, on 4N1-1-induced aggregation of washed human platelets. Thrombin (0.1 U/ml)-induced platelet aggregation was completely inhibited by prostaglandin E1 (PGE1, 300 nM). In contrast, platelet aggregation induced by 4N1-1 (100 microM) was not affected by PGE1. However, epigallocatechin gallate (EGCG), but not other catechins from green tea, concentration-dependently inhibited 4N1-1-induced platelet aggregation. Thus, dietary components, such as EGCG, may inhibit platelet function even under conditions, when 'classical' platelet inhibitors, such as cAMP-elevating agents, are not effective.
authors.affiliation: Medizinische Universitätspoliklinik Bonn, Bonn, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Neuhaus
authors.forename: Simone
authors.initials: S
authors.lastname: Voit
authors.forename: Gereon
authors.initials: G
authors.lastname: Lill
authors.forename: Hans
authors.initials: H
authors.lastname: Vetter
authors.forename: Karsten
authors.initials: K
authors.lastname: Schrör
authors.forename: Artur-Aron
authors.initials: AA
authors.lastname: Weber
mesh_terms: D000527:Alprostadil / Q000494:pharmacology*; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002478:Cells, Cultured; D006801:Humans; D010455:Peptides / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D010979:Platelet Function Tests; D011480:Protease Inhibitors / Q000494:pharmacology*; D019700:Thrombospondin 1 / Q000494:pharmacology*
chemical_list: D010455:Peptides; D010975:Platelet Aggregation Inhibitors; D011480:Protease Inhibitors; D019700:Thrombospondin 1; D002392:Catechin; C045651:epigallocatechin gallate; D000527:Alprostadil