Ping Luo1, Wei-Fang Zhang2, Zhao-Xin Qian3, Ling-Fang Xiao4, Hui Wang5, Tian-Tian Zhu5, Feng Li6, Chang-Ping Hu7, Zheng Zhang8. 1. Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, Hunan 410078, China; Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China. 2. Department of Pharmacy, The Second Affiliated Hospital, Nanchang University, Nanchang, Jiangxi 330006, China. 3. Department of Emergency, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China. 4. Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China. 5. Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, Hunan 410078, China. 6. Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, Hunan 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, Central South University, Changsha, Hunan 410078, China. 7. Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, Hunan 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, Central South University, Changsha, Hunan 410078, China. Electronic address: huchangping@yahoo.com. 8. Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, Hunan 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, Central South University, Changsha, Hunan 410078, China. Electronic address: zzhang@csu.edu.cn.
Abstract
BACKGROUND: Endothelial cell apoptosis contributes to cardiovascular diseases such as hypertension, atherosclerosis. MicroRNA regulates endothelial cell function but its role in endothelial cell apoptosis remains to be fully elucidated. This study aims to investigate the role of miR-590-5p in endothelial cell apoptosis and dissect the underlying mechanisms. METHODS: Flow cytometric analysis, Hoechst 33258 staining and Western blotting were performed to evaluate human umbilical vein endothelial cell (HUVEC) apoptosis induced by Angiotensin (Ang) II. Western blotting and real-time quantitative PCR were conducted to assess the expression of LOX-1. DCFH-DA staining was carried out to measure the generation of reactive oxygen species (ROS). RESULTS: Ang II-induced HUVEC apoptosis was accompanied by downregulation of miR-590-5p; administration of miR-590-5p mimics attenuated HUVEC apoptosis and decreased ROS generation, as indicated by reduced fraction of apoptotic HUVECs and decreased caspase-3 activity. LOX-1 expression was increased by Ang II, and miR-590-5p mimics reduced LOX-1 expression in HUVECs in the absence or presence of Ang II. Pharmacologic or genetic block of LOX-1 with small interference RNA or TS92 (LOX-1 neutralizing antibody) significantly ameliorated HUVEC apoptosis, as evidenced by reduced number of apoptotic HUVECs, inhibited caspase-3 activation and suppressed mitochondrial cytochrome C release. Moreover, LOX-1 siRNA or TS92 treatment dramatically reduced ROS production in HUVECs treated with Ang II. CONCLUSION: Our data demonstrated that miR-590-5p downregulation promoted Ang II-induced endothelial cell apoptosis by elevating LOX-1 expression and consequently increasing ROS generation. Thus, restoration of miR-590-5p or block of LOX-1 could be therapeutically exploited to alleviate endothelial cell apoptosis.
BACKGROUND: Endothelial cell apoptosis contributes to cardiovascular diseases such as hypertension, atherosclerosis. MicroRNA regulates endothelial cell function but its role in endothelial cell apoptosis remains to be fully elucidated. This study aims to investigate the role of miR-590-5p in endothelial cell apoptosis and dissect the underlying mechanisms. METHODS: Flow cytometric analysis, Hoechst 33258 staining and Western blotting were performed to evaluate human umbilical vein endothelial cell (HUVEC) apoptosis induced by Angiotensin (Ang) II. Western blotting and real-time quantitative PCR were conducted to assess the expression of LOX-1. DCFH-DA staining was carried out to measure the generation of reactive oxygen species (ROS). RESULTS: Ang II-induced HUVEC apoptosis was accompanied by downregulation of miR-590-5p; administration of miR-590-5p mimics attenuated HUVEC apoptosis and decreased ROS generation, as indicated by reduced fraction of apoptotic HUVECs and decreased caspase-3 activity. LOX-1 expression was increased by Ang II, and miR-590-5p mimics reduced LOX-1 expression in HUVECs in the absence or presence of Ang II. Pharmacologic or genetic block of LOX-1 with small interference RNA or TS92 (LOX-1 neutralizing antibody) significantly ameliorated HUVEC apoptosis, as evidenced by reduced number of apoptotic HUVECs, inhibited caspase-3 activation and suppressed mitochondrial cytochrome C release. Moreover, LOX-1 siRNA or TS92 treatment dramatically reduced ROS production in HUVECs treated with Ang II. CONCLUSION: Our data demonstrated that miR-590-5p downregulation promoted Ang II-induced endothelial cell apoptosis by elevating LOX-1 expression and consequently increasing ROS generation. Thus, restoration of miR-590-5p or block of LOX-1 could be therapeutically exploited to alleviate endothelial cell apoptosis.