Mol Nutr Food Res. 2016 Mar 23
Propolis is thought to help prevent thrombotic and related cardiovascular diseases in humans. Chrysin, a bioflavonoids compound found in high levels in propolis and in honey, has been reported to possess antiplatelet activity. However, the mechanism by which it inhibits platelet function is unclear.
The effects of chrysin on agonist-activated platelet-aggregation, granule-secretion and integrin αIIbβ3 activation were examined. Its effects on the phosphorylation of Akt, GSK3β, MAPKs and several proteins of the glycoprotein VI (GPVI)-signaling pathway were also studied on collaged-activated platelets. In addition, human platelet spreading on immobilized fibrinogen was also tested.
We found that chrysin dose-dependently inhibited platelet aggregation and granule secretion induced by collagen, as well as platelet aggregation induced by ADP, thrombin and U46619. Chrysin also markedly reduced the number of adherent platelets and the single platelet spreading area on immobilized fibrinogen. Biochemical analysis revealed that chrysin inhibited collagen-induced activation of Syk, PLCγ2, PKC, as well as the phosphorylation of Akt and ERK1/2. Additionally, chrysin attenuated phosphorylation of molecules such as FcγRIIa, FAK, Akt and GSK3β in platelet spreading on immobilized fibrinogen.
CONCLUSIONS AND GENERAL SIGNIFICANCE:
Our findings indicate that chrysin suppresses not only integrin αIIbβ3-mediated "inside-out" signaling, but also the "outside-in" signal transmission. This implies that chrysin may represent a potential candidate for an antiplatelet agent. This article is protected by copyright.