CYP2C8-derived Epoxyeicosatrienoic Acids Decrease Oxidative Stress-induced Endothelial Apoptosis in Development of Atherosclerosis:Role of Nrf2 Activation

摘要

The aim of the present study is to investigate how cytochrome P450 enzymes(CYP) 2C8-derived epoxyeicosatrienoic acids(EETs) regulate the nuclear factor erythroid 2-related factor 2(Nrf2) signaling pathway and protect against oxidative stress-induced endothelial injuries in the development and progression of atherosclerosis. In this study,cultured human umbilical vein endothelial cells(HUVECs) were transfected with CYP2C8 or pretreated with exogenous EETs(1 μmol/L) before TNF-α(20 ng/m L) stimulation. Apoptosis and intracellular ROS production were determined by flow cytometry. The expression levels of ROS-associated NAD(P)H subunits gp91 and p47,the anti-oxidative enzyme catalase(CAT),Nrf2,heme oxygenase-1(HO-1) and endothelial nitric oxide synthase(e NOS) were detected by Western blotting. The results showed that CYP2C8-derived EETs decreased apoptosis of HUVECs treated with TNF-α. Pretreatment with 11,12-EET also significantly blocked TNF-α-induced ROS production. In addition,11,12-EET decreased oxidative stress-induced apoptosis. Furthermore,the ability of 11,12-EET to protect cells against TNF-α-induced apoptosis via oxidative stress was abrogated by transient transfection with Nrf2-specific small interfering RNA(si RNA). In conclusion,CYP2C8-derived EETs prevented TNF-α-induced HUVECs apoptosis via inhibition of oxidative stress associated with the Nrf2 signaling.