The Protective Effects Of Capsaicin In Cardiomyocytes From Anoxia/Reoxygenation Injury Are Mediated By SIRT1

Objective:Capsaicin is the active ingredient of chili pepers and gives the charactrastic pungent flavor.A beneficial role of capsaicin has been reported in cardiovascular in recent studies.SIRT1,an ubiquitous NAD(+)-dependent deacetylase that plays a role in myocardial anoxia/reoxygenation injury.In our study,we have established the cultured neonatal rat primary cardiomyocytes model with the acute myocardial anoxia/reoxygenation(A/R)injury model.We aim to explore the relationship between the protective effect of capsaicin against myocardial anoxia/reoxygenation injury and the mechanism of SIRT1 cardioprotection.Method:The cultured newborn rat of two or three days myocardiocytes were randomly divided into four groups,each group repeated six times:(1)Control group;(2)A/R group;(3)Cap+A/R group;(4)Cap+Sirtinol+A/R group.Western blotting analysis assayed the expression of SIRT,antiapoptotic Bcl-2 proteins,apoptosis-regulated factor Cytochrome C and apoptosis-regulated gene caspase-3;The cell viability was detected by MTS;According to the kit,the activity of LDH,CPK,SOD,GSH-Px,MDA and caspase-3 activity was analyzed with UV spectrophotometer;The standard of intracellular ROS,the mitochondrial membrane potential and the apoptosis were detected by flow cytometry.Results:1.Preconditioning with capsaicn,the expression of SIRT1 protein were increased compared to A/R group,preprocessing 20μM capsaicin was significantly raised compared to A/R group(p<0.01).2.a.After A/R injury,all indicators were significant differences(p<0.01),which indicated A/R model was success.b.In Cap+A/R group,the LDH and CPK were decreased,cell viability was increased,MDA was decreased,SOD and GSH-Px were increased;decreased Cyt C(cytoplasm)and cleaved Caspase-3 along with elevated expression of Bcl-2;the ROS production was decreased,the stability of mitochondria membrane was increased and the apoptosis was decreased.Compared to A/R group,all indicators were significant differences(p<0.01);c.All indicators in the Cap+Sirtinol+A/R group were significant differences when compared to Cap+A/R group(p<0.01),but no significant differences when compared to A/R group(p>0.05).Conclusion:Capsaicin against myocardial anoxia-reoxygenation injury are involved in SIRT1 pathway,and at least partly SIRT1-dependent.