High-fat diet-induced platelet hyperreactivity in mice is dependent on Fyn/Vav1 signaling axis. (A) Platelets from WT and vav1^−/− mice on chow or western diet for 2 weeks were stimulated with 2μM ADP. Aggregation was assessed turbidimetrically with a dual-channel aggregometer. Shown are representative curves. (B) Aggregation amplitude of platelets from WT or vav1^−/− mice on chow or western diet or fyn^−/− mice on western diet for 2 weeks incubated with 2 or 5μM ADP as indicated. (C) Platelets from WT and vav1^−/−;Vav3^−/− mice on chow or western diet for 2 weeks were treated with 1μM ADP. Aggregation was assessed turbidimetrically with a dual-channel aggregometer. Aggregation amplitudes were shown as indicated. (D) Platelets from WT and vav1^−/−;Vav3^−/− mice were column purified and incubated with 40 μg/mL native LDL or oxLDL. After 20 minutes, platelets were further incubated with or without 1μM ADP and with JonA Ab for 10 minutes and then fixed before subject to flow cytometric analysis. Percentage increases in MFI of stained platelets treated with ADP and oxLDL in comparison to that of platelets treated with ADP and native LDL were shown.