Betanin-enriched red beet extract attenuated platelet activation and aggregation by suppressing Akt and P38 Mitogen-activated protein kinases phosphorylation

Betanin, a water-soluble nitrogenous pigment, is found to exert various health benefits including anti-oxidative, anti-inflammatory, anti-hyperglycemic and cardioprotective effects. However, the roles of betanin in platelet function is completely unknown. In the present study we investigated the effects of betanin-enriched red beet extract on human platelet physiology in vitro and explored the underlying mechanism. The results showed that betanin significantly and dose-dependently reduced platelet P-selectin, CD63, CD40L expression and PAC-1 binding, inhibited ATP secretion and platelet aggregation. Meanwhile, betanin didn’t prolong tail bleeding time in C57BL/6 mice. Western blot results demonstrated that betanin attenuated platelet Akt and P38 MAPK phosphorylation induced by thrombin. Taken together, betanin could attenuate platelet function without affecting bleeding time, and this effect is potentially mediated by inhibition of Akt and P38 MAPK phosphorylation. Our findings suggest that betanin could be considered as a candidate agent for the prevention of platelet-associated thromboembolic CVDs.