埋线预处理对缺血再灌注损伤ZDF大鼠心肌ATG9A及p62蛋白表达的影响

Effects of catgut implantation preconditioning on expressions of ATG9A and p62 protein in myocardial ischemia reperfusion injury in ZDF rats

目的:以自噬相关蛋白9A(ATG9A)及p62为关键点,探讨埋线预处理防治心肌缺血再灌注损伤的作用机制。方法:ZDF大鼠随机分为:正常组、模型组、缺血预处理组和埋线预处理组。以推管法制备缺血再灌注损伤模型。电镜观察心肌组织超微结构;测定乳酸脱氢酶(LDH)和肌酸激酶同工酶(CK-MB)的活性变化;Western blot法检测ATG9A及p62蛋白表达的水平。结果:电镜下,缺血预处理组及埋线预处理组自噬泡数量较模型组明显增多,心肌超微结构损伤较轻;与模型组比较,缺血预处理组和埋线预处理组血清LDH、CK-MB值均明显下降(P<0.01),心肌ATG9A蛋白表达显著上升(P<0.01),p62蛋白水平下降(P<0.01)。结论:埋线预处理可能通过上调心肌中ATG9A、下调p62的表达水平激活自噬,从而有效对抗缺血再灌注损伤。

Objective: To explore the mechanism of catgut implantation pretreatment against myocardial ischemiareperfusion injury by using autophagy-related proteins ATG9 A and p62 as key points.Methods: ZDF rats were randomly divided into normal group,model group,ischemic preconditioning group and catgut implantation pretreatment group.The model of ischemia-reperfusion injury was established by pushing tube method.The ultrastructure of myocardium was observed by electron microscope.The changes of lactate dehydrogenase(LDH) and creatine kinase isoenzyme(CK-MB) were measured.The expressions of ATG9 A and p62 protein were detected by Western blot.Results: The number of autophagic vacuoles in ischemic preconditioning group and catgut implantation pretreatment group were significantly higher than that in model group,and the ultrastructural damage was lighter.Compared with the model group,the levels of serum LDH and CK-MB in ischemic preconditioning group and catgut implantation pretreatment group were significantly decreased(P<0.01),the expression of ATG9 A protein was increased(P<0.01) and the level of p62 protein decreased(P<0.01).Conclusion: Catgut implantation pretreatment may activate autophagy by up-regulating the expression of ATG9 A in myocardium and down-regulating the expression of p62,so as to effectively antagonize ischemia-reperfusion injury.