摘要
目的探讨凋亡抑制剂zVAD对脑缺血再灌注小鼠线粒体DNA拷贝数的影响。方法 80只雄性25~30gC57BL/6小鼠,随机分为大脑中动脉栓塞(MCAO)模型组(3组共24只)、模型给药组(3组共24只)、假手术组(3组共24只)和对照组(8只)。MCAO模型组应用线栓法,构建小鼠大脑中动脉栓塞模型并在1h后进行再灌注,模型给药组在再灌注前腹腔注射10mmol/L的ZVAD10mL/kg,假手术组暴露颈内动脉后缝合皮肤,对照组不进行任何操作。分别于再灌注后不同时间点(24、48、72h),对经手术操作的每组各8只小鼠进行改良神经功能损伤评分(mNSS),评分后取血约200μL并提取外周血基因组DNA,real-time PCR法检测相对线粒体DNA拷贝数。结果 MCAO模型组和模型给药组术后24、48和72h的mNSS评分均明显高于相应对照组(P〈0.05),术后48、72h,模型给药组mNSS评分均明显低于相应MCAO模型组(P〈0.05);术后24、48 h,MCAO模型组和模型给药组线粒体DNA拷贝数均高于对照组或假手术组,模型给药组高于MCAO模型组(P〈0.05);术后72h,各组的线粒体DNA拷贝数差异无统计学意义(F=1.58,P〉0.05)。结论凋亡抑制剂zVAD对脑缺血再灌注小鼠可起到一定的脑保护作用,这可能由于zVAD抑制了线粒体介导的凋亡通路,并通过端粒—线粒体途径促进了外周血线粒体DNA拷贝数的升高。
Objective To explore the influence of the apoptosis inhibitor zVAD on peripheral mitochondrial DNA copy number in cerebral ischemia reperfusion mice.Methods 80 male C57BL/6 mice were randomly divided into middle cerebral artery occlusion(MCAO) group(24 mice divided into 3 group equally),drug given group(24mice divided into 3 group equally),sham group(24 mice divided into 3 group equally) and control group(8mice).MCAO group were conducted by the intraluminal filament technics and reperfusion was made 1 h later.Drug given group was given 10 mmol/L zVAD 10 mL/kg by peritoneal injection.Sham group were conducted with an incision on skin of neck and sewed it immediately,no operations were carried out in control group.At different time after operation(24 h,48 h,72 h),neurological function was evaluated according to the modified Neurological Severity Score(mNSS),genomic DNA was extracted from 200 μl blood.Mitochondrial DNA copy number was measured by real-time PCR.Results The mNSS of either MCAO group or drug given group were higher than sham group at 24 h 48 h and 72 h(all P 〈0.05).The mNSS of drug given group were significantly lower than MCAO group at 48 h and 72 h(all P〈0.05).At 24 h and 48 h,the mitochondrial DNA copy number of MCAO group and drug given group mice were increased when compared with sham group or control group,with the drug given group was the highest among the four groups(all P 〈0.05),but there was no significant difference among the four groups at 72h(P 〉0.05).Conclusion The apoptosis inhibitor zVAD can play a protective role on neurological function in cerebral ischemia reperfusion mice.The potential reason may be that zVAD inhibited the mitochondria-mediated apoptotic pathway,as well as promoted the increase of mitochondrial DNA copy number via telomeres-mitochondria pathway.
出处
《遵义医学院学报》
2016年第6期593-596,共4页
Journal of Zunyi Medical University
基金
天津市卫生局科技基金资助项目(NO:2015KZ126)
天津市卫生和计划生育委员会中医中西医结合科研课题(NO:2015155)
天津市神经创伤修复重点实验室开放基金资助项目(NO:WYKFZ201602)
武装警察部队后勤学院基础研究项目(NO:WHJ2015013)
武装警察部队后勤学院附属医院种子基金资助项目(NO:FYM201517
NO:FYQ201560)
关键词
凋亡抑制剂
脑缺血再灌注
线粒体DNA拷贝数
改良神经功能损伤评分
apoptosis inhibitor
cerebral ischemia and reperfusion
mitochondrial DNA copy number
Modified Neurological Severity Score(mNSS)