Quercitrin exhibits important effect on P-selectin exposure and
αIIbβ3 integrin activation following agonist stimulation
Next, we investigated the effects of quercitrin on P-selectin exposure
and αIIbβ3 integrin activation, which are key processes driving the
positive feedback cycle of platelet activation. Because quercitrin
prevented platelet aggregation and ADP secretion induced by CRP and
U46619 stimulation, we examined P-selectin exposure and αIIbβ3 integrin
activation using CRP (0.1 µg/ml) or U46619 (3 µM). Following 10 minutes
of pre-incubation, quercitrin significantly inhibited CRP- or
U46619-induced P-selectin exposure (Figure 2A and 2C) and αIIbβ3
integrin activation (Figure 2B and 2D) in a concentration-dependent
manner (10, 20, and 30 µM), whereas quercitrin failed to block the
effects of thrombin stimulation (Figure S3). These results suggest that
quercitrin selectively inhibits platelet activation through effects on
granule secretion and αIIbβ3 integrin activation.