Triflavin, an αiIβ3 disintegrin, inhibits cell adhesion and protein kinase C-α translocation in vascular smooth muscle cells

Vascular smooth muscle cell (VSMC) adhesion and migration play important roles in atherosclerosis and intimal hyperplasia. In our previous study, we found that triflavin, a nonspecific Arg-Gly-Asp (RGD)-containing peptide (also named αIIβ3 disintegrin), may have dual beneficial effects in preventing neointimal formation by acting on both platelets and VSMCs, which has created new incentives for the development of drugs with this combined action. In the present study, triflavin (10, 20, and 50μg/mL) concentration- dependently inhibited VSMC adhesion to immobilized fibronectin (50μg/mL). In the flow cytometric study, we found that FITCtriflavin (5μg/mL) bound directly to VSMC membranes. In a confocal microscopic study, fibronectin (50μg/mL) markedly stimulated protein kinase C (PKC)-α translocation from the cytosol to the membranes, which was abolished in the presence of triflavin (10μg/mL). In conclusion, the most important findings of this study suggest that triflavin, an αIIβ3 disintegrin, inhibited immobilized fibronectin-induced cell adhesion and PKC-α translocation in VSMCs.