小鼠脑缺血时自噬相关基因5的抗损伤作用  

Knockdown of Atg5 aggravates cerebral ischemia and reperfusion injury in mice

作　　者：彭志锋[1] 王喜英[2] 杨靖辉[1] 

机构地区：[1]山西大同大学医学院生理教研室,山西大同037009 [2]山西大同大学医学院微生物与免疫学研究所,山西大同037009

出　　处：《中国病理生理杂志》2016年第1期64-68,共5页Chinese Journal of Pathophysiology

基　　金：山西大同大学博士科研启动经费;山西省基础研究项目(No.2015021178)

摘　　要：目的:观察自噬相关基因5(Atg5)在小鼠脑缺血再灌注损伤中的抗损伤作用。方法:将雄性BALB/c小鼠随机分为假手术(sham)组、缺血再灌注(I/R)组、Atg5 siRNA组和control siRNA组。I/R组采用大脑中动脉阻塞(MCAO)60 min后再灌注24 h。Atg5 siRNA组和control siRNA组将5μL Atg5 siRNA或scrambled siRNA在MCAO前24 h侧脑室注射。实时荧光定量PCR和Western blot检测Atg5的表达;2,3,5-氯化三苯基四氮唑(TTC)染色法检测抑制Atg5对缺血再灌注损伤后脑梗死面积和水肿率的影响;神经行为学评分法检测抑制Atg5对缺血再灌注损伤后神经症状的影响。结果:MCAO后再灌24 h,缺血半影区Atg5 mRNA和蛋白水平显著增高(P<0.05);Atg5 siRNA明显降低缺血再灌后Atg5 mRNA和蛋白的表达(P<0.05);侧脑室给予Atg5 siRNA能显著增加脑梗死面积和水肿率,并加重神经行为学损伤(P<0.05)。结论:沉默Atg5加重小鼠脑缺血再灌损伤,提示MCAO后诱导的Atg5可减轻小鼠局灶性脑缺血再灌注损伤。AIM： To study the role of autophagy-related gene 5（ Atg5） in cerebral ischemia and reperfusion injury in mice. METHODS： BALB / c male mice（ weighing 18 ~ 22 g） were randomly divided into sham group,ischemia /reperfusion（ I / R） group,Atg5 siRNA group and control siRNA group. Focal cerebral ischemia was performed using the method of middle cerebral artery occlusion（ MCAO） for 60 min and reperfusion for 24 h. In siRNA group and control group,5 μL Atg5 siRNA or scrambled siRNA was administered by intracerebroventricular injection 24 h before MCAO.The expression of Atg5 at mRNA and protein levels in ischemic cortex at 24 h after reperfusion was determined by real-time PCR and Western blot. The infarct volume and edema were evaluated by TTC staining,and motor deficits were evaluated by neurological scoring. RESULTS： The expression of Atg5 at mRNA and protein levels was significantly increased 24 h after reperfusion in I / R group compared with sham group. Atg5 siRNA obviously decreased the expression of Atg5 at mRNA and protein levels induced by I / R. Inhibition of Atg5 exacerbated the infarct volume and ameliorated the neurological symptoms. CONCLUSION： Atg5 has neuroprotective effect on focal cerebral ischemia and reperfusion injury.

关 键 词：自噬相关基因5 自噬 缺血再灌注损伤 

分 类 号：R363.1[医药卫生—病理学]