Mechanism Of Pretreatment With Ferulic Acid Against Lipopolysaccharide-induced Myocardial Injury Mediated By AMPKα2

Objective:To explore the protective effects of Ferulic acid pretreatment against septic cardiomyopathy by upregulating AMPKα2.Methods:1.In vitro H9c2 cells were established LPS/Nigericin injury model.The pretreatment concentration of FA was determined through detecting cell viability and LDH activity.The levels of inflammatory cytokines,including TNF-α and IL-1β,were measured using ELASA kits.The activities of related antioxidant enzymes such as GSH-Px,CAT,SOD and MDA content were estimated.The DHE staining was used to assess the level of ROS.The related proteins including AMPKα2,p-AMPKα,Bcl-2,Bax and Cleaved Caspase-3 were studied using Western blot.Both Annexin V-FITC/ PI assay kit and TUNEL kit were applied to determine apoptosis.2.In vivo C57/BL6 mice were induced septic cardiomyopathy via intraperitoneal injection of LPS.The cardiac function of mice was assessed by using echocardiography and HE staining kit and detecting the activities of CK and LDH in serum.The levels of inflammatory cytokines in serum,including TNF-α and IL-1β,were measured using ELASA kits.The activities of related antioxidant enzymes such as GSH-Px,CAT,SOD and MDA content were estimated.The related proteins including AMPKα2,p-AMPKα,Bcl-2,Bax and Cleaved Caspase-3 were studied using Western blot.Enzyme labeling was performed to detect Caspase-3 activity in cardiac tissue.TUNEL kit was performed to determine apoptosis.Results:Research results in vitro indicated FA pretreatment inhibited over-secretion of inflammatory factors,oxidative stress and reduced apoptotic rate through upregulating AMPKα2 expression and AMPKα phosphorylation level in LPS/Nigericin-induced H9c2 cells.However,Compound C(AMPK inhibitor)could reverse those protective effects of FA.Research results in vivo indicated FA decreased the levels of inflammatory factors in serum,strengthened antioxidant activities,inhibited the formation of apoptotic bodies and improved cardiac systolic and diastolic function by upregulating AMPKα2 expression and AMPKα phosphorylation level.However,Compound C could suppress those protective effects of FA.Conclusion:FA pretreatment reduced oxidative stress,inhibited apoptosis and inflammatory response through upregulating AMPKα2 expression to protect cardiomyocytes against lipopolysaccharide injury.