We investigated the anti-platelet activity of THSG on platelet aggregation induced by collagen (2 渭g/mL), thrombin(0.04U/mL), U46619 (3 渭M) and ADP (2 渭M). ATP secretion induced by collagen (2 渭g/mL) was also investigated. P-selectin expression and PAC-1 binding were measured by flow cytometry. In addition, human platelet spreading on immobilized fibrinogen and immunoblotting were also tested.
THSG dose-dependently inhibited platelet aggregation and ATP secretion induced by collagen. It inhibited platelet P-selectin expression and PAC-1 binding induced by thrombin(0.1U/mL). THSG also inhibited human platelet spreading on immobilized fibrinogen, a process mediated by platelet outside-in signaling. Western blot analysis showed that THSG could inhibit platelet Fc 纬 RIIa, Akt(Ser473)and GSK3尾(Ser9) phosphorylation.
Our study indicates that THSG has potent anti-platelet activity to collagen induced aggregation. THSG is likely to exert protective effects in platelet-associated thromboembolic disorders by modulating human platelet.