Abstract:Objective: Platelet activation induced by oxidized low-density lipoprotein (ox-LDL) its mediation by Src/Syk/ROS signaling plays a key role in thrombus formation during hyperlipidemia. Sulforaphane (SFN), a phytochemical belonging to the family of isothiocyanates enriched in cruciferous vegetables, exhibits a variety of biological activities. The current study would like to determine the effects of SFN on ox-LDL-induced platelet activation and its possible mechanism. Methods: Purified human platelets were treated with SFN (1, 2.5, 5 μmol/L) for 40 minutes in vitro, and then stimulated by ox-LDL for additional 20 minutes. The levels of platelet CD62P expression and intracellular PF4 and CCL5 release were measured to determine the effects of SFN on platelet activation. Moreover, the phosphorylation of sarcoma tyrosine kinase (Src) and its downstream spleen tyrosine Kinase (Syk) were measured by Western blot. Reactive oxygen species (ROS) assay kit was used to measure the levels of total intracellular ROS generation. Results: Ox-LDL-increased platelet CD62P expression and PF4 and CCL5 release were significantly inhibited by SFN when compared with the control group (P < 0.05). SFN treatment greatly down-regulated Src and Syk phosphorylation and ROS generation stimulated by ox-LDL (P < 0.05). Furthermore, ox-LDL-increased the expression of CD62P and release of PF4 and CCL5 were significantly abolished by PP2, a specific inhibitor of Src family kinases, which, nevertheless, showed no synergistic effects when combined with SFN (P > 0.05). In addition, the inhibitory effects of SFN on platelet activation induced by ox-LDL were reversed by an activator of Src family kinases MLR-1023. Conclusions: SFN attenuates platelet activation induced by ox-LDL possibly by down-regulating Src/Syk/ROS pathway.