APOE and atherosclerosis: Studies from Schafer et al. (2003) pointed that oxidative stress was important in the process of thrombosis by observation that ROS upregulated the expression level of PAI-I in endothelial cells, and enhanced PAI-1 expression in vasculature promotes prothrombotic phenotype and atherosclerosis in ApoE–/– mice, which is consistent with the improved coagulation parameters following NAC administration in this study.