Effects of Ginkgo biloba extract on production of ROS in human coronary artery endothelial cells induced by activated platelets

GOU Xuerui; LI Zhongdong; WANG Zhaohao; SHI Erlan; WANG Jianchang

Abstract：ObjectiveTo establish a model of oxidative stress invitro via HCAECs induced by activated-platelets in order to explore whether different dosages of Ginkgo biloba extract (EGb) might synergistically suppress reactive oxygen species (ROS) produced in HCAECs by regulating the expression of NOX4 and RhoA in HCAECs.MethodsHCAECs stressed with activated platelets 2×108/ml, were divided into 4 groups: activated platelets group, 4, 40, 400μg /ml EGb groups. In addition, HCAECs served as the control group. EGb (4, 40 or 400μg/ml) was treated for 12 h. ROS in HCAECs was measured with a DCFH-DA probe and observed by fluorescence microscopy. The expression of NOX4 and RhoA was examined by Western Blot.ResultsThe results of fluorescence microscopy showed that in HCAECs, intracellular ROS was markedly increased (P<0.05), after stimulation of activated platelets, compared with HCAECs control group. Compared with activated platelets group, EGb inhibited ROS in HCAECs in a dosage dependent manner (P<0.05). By Western blot analysis, we found that cowpared with HCAECS control group, the expression of NOX4 and RhoA in HCAECs stresscd by activated platelets was markedly enhanced (P<0.05 ). Compared with activated platelet group, EGb reduced the expression of NOX4 in a dosage dependent manner (P<0.05).ConclusionEGb can attenuate the expression of ROS, NOX4 and RhoA in HCAECs induced by activated platelets in vitro. That the mechanism of EGb in the treatment of coronary atherosclerotic heart disease may be correlated with the inhibition of ROS production by suppressing NOX4 and RhoA expression.