International Journal of COPD (Mar 2022)
Prohibitin Protects Pulmonary Microvascular Endothelial Cells Against Cigarette Smoke Extract-Induced Cell Apoptosis and Inflammation
Abstract
Yating Peng,1– 3 Wei Cheng,1– 3 Jiaxi Duan,1– 3 Yiyang Zhao,1– 3 Zijing Zhou,1– 3 Aiyuan Zhou,1– 3 Minhua Deng,1– 4 Hong Peng,1– 3 Ruoyun Ouyang,1– 3 Yan Chen,1– 3 Ping Chen1– 3 1Department of Pulmonary and Critical Care Medicine, Second Xiang Ya Hospital, Central South University, Changsha, Hunan, 410011, People’s Republic of China; 2Institute of Respiratory Disease, Central South University, Changsha, Hunan, 410011, People’s Republic of China; 3Hunan Centre for Diagnosis and Treatment of Respiratory Disease, Changsha, Hunan, 410011, People’s Republic of China; 4Department of Respiratory, PLA Rocket Force Characteristic Medical Center, Beijing, 100088, People’s Republic of ChinaCorrespondence: Ping Chen, Email [email protected]: Prohibitin has been identified to play roles in cell survival and apoptosis. Here, this study aimed to clarify the role of prohibitin in cigarette smoke extract (CSE)-induced endothelial cell apoptosis.Methods: The protein level of prohibitin was assessed by Western blot in lung tissues from emphysema and control mice. CSE-induced human pulmonary microvascular endothelial cells (hPMECs) were applied to mimic smoke-related cell apoptosis in vitro. Prohibitin was overexpressed in hPMECs with or without CSE. Mitochondrial function was analyzed by JC-1 staining and ATP assay kits. Oxidative stress was assessed by flow cytometry, fluorescence staining and immunocytochemistry. Apoptosis was analyzed by flow cytometry, Western blot and caspase-3 activity assays. In addition, the expression of inflammatory markers was assessed by Western blot and real-time polymerase chain reaction (PCR). The secretion of inflammatory cytokines was measured by ELISA.Results: Prohibitin was downregulated in emphysema mouse tissues compared with control experiments. Consistently, CSE inhibited both the protein and RNA levels of prohibitin in hPMECs in a dose-dependent manner. Gain-of-function experiments indicated that CSE induced collapse of mitochondrial membrane potential (MMP) and loss of ATP, while prohibitin improved mitochondrial function. CSE induced robust ROS production and oxidative DNA damage, while prohibitin decreased this damage. Upregulation of prohibitin protected the apoptosis of hPMECs from CSE. Overexpression of prohibitin significantly reduced the levels of the main proinflammatory cytokines. Finally, prohibitin inhibited nuclear factor-kappa B (NF-κB) p65 accumulation and IκBα degradation induced by CSE.Conclusion: The current findings suggest that CSE-mediated mitochondrial dysfunction, oxidative stress, cell apoptosis and inflammation in hPMECs were reduced by overexpression of prohibitin. We identified prohibitin as a novel regulator of endothelial cell apoptosis and survival in the context of CSE exposure.Keywords: prohibitin, hPMECs, CSE, apoptosis, mitochondrial, inflammation