Liwei Hang1,2,3,4,5, Yan Peng6, Rui Xiang7, Xiangdong Li8, Zhiliang Li1,2,3,4. 1. Department of Cardiology, Heart Center, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510280, People's Republic of China. 2. Laboratory of Heart Center and Department of Cardiology, Heart Center, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510280, People's Republic of China. 3. Guangdong Provincial Biomedical Engineering Technology Research Center for Cardiovascular Disease, Guangdong, Guangdong 510280, People's Republic of China. 4. Sino-Japanese Cooperation Platform for Translational Research in Heart Failure, Guangzhou, Guangdong 510280, People's Republic of China. 5. Department of Cardiology, Dongsheng People's Hospital, Erdos City, Inner Mongolia 017000, People's Republic of China. 6. Department of Critical Care Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, People's Republic of China. 7. Department of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, People's Republic of China. 8. Fuwai Hospital, National Center of Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, People's Republic of China.
Abstract
OBJECTIVE: This study was to investigate the mechanism of inflammatory pathology modification induced by ox-LDL in endothelial cells. METHODOLOGY: In this study, we firstly investigated the efflux of cholesterol of endothelial cells under the treatment of ox-LDL, and cell proliferation, ROS production, cell apoptosis was measured. Further, proteins of ASK1, NLRP3 inflammasomes and endoplasmic reticulum stress response were detected. Afterwards, ASK1 inhibitor (GS-4997) or endoplasmic reticulum stress (ERS) inhibitor (4-PBA) was used to measure the performance of endothelial cells. RESULTS: In this study, endothelial cells were treated with ox-LDLs alone or in combination with a GS-4997 or 4-PBA. Results showed that ox-LDLs attenuated the efflux of cholesterol from endothelial cells in a dose-dependent manner. Ox-LDLs inhibited the proliferation of endothelial cells, and induced their apoptosis and production of reactive oxygen species (ROS). Additionally, ox-LDLs upregulated the levels of phosphorylated ASK1, ERS-related proteins (chop, p-PERK, GRP78, and p-IRE-1), and inflammation-associated proteins (NLRP3, IL-1β, and caspase 1) in endothelial cells. Moreover, we proved that GS-4997 could partly reverse ox-LDL-mediated cell proliferation, apoptosis, ROS production, and inflammation in endothelial cells, and increase cholesterol efflux. We also found that 4-PBA could attenuate the effects of ox-LDLs on endothelial cell cholesterol efflux, proliferation, apoptosis, ROS production, and inflammation. CONCLUSION: Our results suggest that cholesterol efflux from endothelial cells is reduced by ox-LDLs, and these reductions in cholesterol efflux are accompanied by increased NLRP3 inflammasome signaling, ASK1 and higher levels of endoplasmic reticulum stress. Our results suggest this axis as potential targets for treating atherosclerosis.
OBJECTIVE: This study was to investigate the mechanism of inflammatory pathology modification induced by ox-LDL in endothelial cells. METHODOLOGY: In this study, we firstly investigated the efflux of cholesterol of endothelial cells under the treatment of ox-LDL, and cell proliferation, ROS production, cell apoptosis was measured. Further, proteins of ASK1, NLRP3 inflammasomes and endoplasmic reticulum stress response were detected. Afterwards, ASK1 inhibitor (GS-4997) or endoplasmic reticulum stress (ERS) inhibitor (4-PBA) was used to measure the performance of endothelial cells. RESULTS: In this study, endothelial cells were treated with ox-LDLs alone or in combination with a GS-4997 or 4-PBA. Results showed that ox-LDLs attenuated the efflux of cholesterol from endothelial cells in a dose-dependent manner. Ox-LDLs inhibited the proliferation of endothelial cells, and induced their apoptosis and production of reactive oxygen species (ROS). Additionally, ox-LDLs upregulated the levels of phosphorylated ASK1, ERS-related proteins (chop, p-PERK, GRP78, and p-IRE-1), and inflammation-associated proteins (NLRP3, IL-1β, and caspase 1) in endothelial cells. Moreover, we proved that GS-4997 could partly reverse ox-LDL-mediated cell proliferation, apoptosis, ROS production, and inflammation in endothelial cells, and increase cholesterol efflux. We also found that 4-PBA could attenuate the effects of ox-LDLs on endothelial cell cholesterol efflux, proliferation, apoptosis, ROS production, and inflammation. CONCLUSION: Our results suggest that cholesterol efflux from endothelial cells is reduced by ox-LDLs, and these reductions in cholesterol efflux are accompanied by increased NLRP3 inflammasome signaling, ASK1 and higher levels of endoplasmic reticulum stress. Our results suggest this axis as potential targets for treating atherosclerosis.