Therapeutic Potential of Cytosolic PLA2 Isoform–Specific Inhibitor Arachidonyl Trifluromethyl Ketone in Cigarette Smoke Condensate–Induced Pathological Conditions in Alveolar Type I and II Epithelial Cells

Abstract

Background: Cigarette smoking is responsible for various lung pathologies including chronic lung inflammation, emphysema, chronic obstructive pulmonary disease (COPD), cancer, and annually causes almost 10 million deaths globally. During smoke exposure, most affected cells are the alveolar epithelial cells where as a repair mechanism, activation of cytosolic phospholipase A2 enzymes takes place. High free radicals and cPLA2 activity due to continuous exposure of smoke exposure leads to elevated levels of secondary metabolites and various pathophysiologic conditions such as chronic inflammation, oxidative stress and cancer. To reduce the burden of chronic inflammation as well as oxidative stress, and higher levels of secondary metabolites whose role is well defined in progression of cancer, we checked the therapeutic potential of cPLA2 inhibitor arachidonyl trifluromethyl ketone (ATK) by pharmacologically targeting the most expressible cPLA2 during continuous exposure of cigarette smoke. Aim: To check the therapeutic potential of cytosolic PLA2 isoform specific inhibitor arachidonyl trifluromethyl ketone in cigarette smoke condensate–induced pathologic conditions in alveolar type I and II epithelial cells. Methods: Effect of cPLA2 inhibitor on CSC-induced cPLA2 activity were checked using colorimetric assay, cell viability using MTT assay, FDA uptake assay using fluorescence microscopy, ROS levels and apoptosis markers through flow cytometry, and ERK levels using ELISA, in both type of alveolar epithelial cells. Results: ATK significantly mimicked CSC-induced cPLA2 activity, free radicals, primary apoptosis, ratio of apoptotic/apoptotic proteins and levels of ERK whereas protected cells from loss of cell viability and membrane integrity. Conclusion: Current observations revealed cPLA2s as a potential therapeutic target and their inhibitor ATK as a potential therapeutic agent in Cigarette smoke induced pathological conditions in alveolar type I and II epithelial cells.