The Relationship Between MiR-27a And SIRT1 During Myocardial Ischemia-Reperfusion Injury In Rats

Objective: To investigate the relationship between miR-27 a and SIRT1 during myocardial ischemia-reperfusion injury in rats.Methods: Forty clean grade healthy SD male rats,weighing 280-320 g.The rats were divided into 4 groups(n=10)according to the random number table method: sham-operated group(Sham group),ischemia-reperfusion group(I/R group),AAV9-miR-27 a overexpression group(AAV+I/R group),and AAV-9 miR-27 a negative control group(NC+I/R group).A model of myocardial ischemia-reperfusion injury was prepared by ligating the anterior descending branch of the left coronary artery for 30 min and reperfusing for 120 min.miR-27 a overexpression was achieved by tail vein injection of adeno-associated virus in the AAV+I/R group.At the end of 120 min of reperfusion,myocardial tissues from the left ventricular ischemia-reperfusion area were stained with TTC to calculate myocardial infarct area,blood was collected from the abdominal aorta,and serum cTn-T,CK-MB and LDH concentrations were measured by ELISA,myocardial glutathione(GSH),superoxide dismutase(SOD)and propylene glycol(MDA)levels were measured by ELISA,and western blot method to determine the expression of Sirt1 in myocardial tissues.Results: Compared with the Sham group,myocardial infarct area,serum cTn-T,CK-MB,and LDH concentrations were increased,myocardial tissue GSH and SOD levels were decreased,MDA levels were increased,and SIRT1 expression was downregulated in the I/R group;compared with the I/R group,myocardial infarct area,serum cTn-T,CK-MB,and LDH concentrations were increased,and myocardial tissue GSH and SOD levels were decreased,MDA levels were increased,and SIRT1 expression was downregulated in the AAV+I/R group.Myocardial tissue GSH and SOD levels decreased,MDA levels increased,and SIRT1 expression was downregulated(P < 0.05);compared with the I/R group,myocardial infarct area,serum cTn-T,CK-MB,LDH concentrations,myocardial tissue GSH,SOD and MDA levels,and Sirt1 expression in the NC+I/R group were not statistically significant(P>0.05)Conclusion: miR-27 a may aggravate myocardial ischemia-reperfusion injury in rats by inhibiting SIRT1 protein expression.