let-7a通过抑制Fas/FasL抑制缺氧缺血性新生大鼠脑组织的细胞凋亡

let-7a Inhibits Cell Apoptosis in Hypoxic-Ischemic Neonatal Rat Brain Tissue by Inhibiting Fas/FasL

该文旨在探究let-7a是否通过抑制Fas/FasL减轻缺氧缺血性新生大鼠脑组织的细胞凋亡。通过结扎颈动脉建立新生大鼠缺氧缺血性模型。将60只SPF级SD新生大鼠随机分为:假手术组(Sham组)、模型组(Model组)、let-7a激动剂(agomir)组、阴性对照(NC)agomir组、let-7a agomir+Fas激活剂组,每组12只。造模后进行药物注射,Sham组和Model组注射等量生理盐水。给药结束后,使用神经功能缺损程度评分法(NDS)评价各组大鼠神经功能。HE染色观察各组大鼠脑组织的病理学变化。RT-qPCR法测定各组大鼠脑组织中let-7a、Fas和FasL mRNA表达水平;Western blot检测各组大鼠脑组织中Fas/FasL信号通路及凋亡相关蛋白表达水平;TUNEL染色检测各组大鼠脑组织中细胞凋亡率;双荧光素酶报告基因实验检测let-7a与Fas、FasL的靶向关系。与Sham组相比,Model组大鼠NSD评分,细胞凋亡率,脑组织中Fas、FasL mRNA表达水平,Fas、FasL、Bax和Caspase-3蛋白表达水平显著升高(P<0.05),脑组织病理损伤严重。与Model组相比,NC agomir组大鼠各项指标均无显著性差异(P>0.05);let-7a agomir组大鼠NSD评分,脑组织的细胞凋亡及Fas、FasL表达水平显著减少(P<0.05),病理损伤有所减轻。Fas激活剂减弱了过表达let-7a对缺氧缺血性新生大鼠脑组织细胞凋亡的抑制作用(P<0.05)。let-7a与Fas、FasL均存在靶向关系。let-7a可能通过抑制Fas/FasL减轻缺氧缺血性新生大鼠脑组织的细胞凋亡。

This study was to explore whether let-7a alleviated the cell apoptosis in hypoxic-ischemic neonatal rat brain tissue by inhibiting Fas/FasL.A hypoxic-ischemic model of neonatal rats was established by ligating the carotid artery.Sixty SPF SD neonatal rats were randomly grouped into:sham operation group(Sham group),Model group,let-7a agonist(agomir)group,negative control(NC)agomir group,and let-7a agomir+Fas activator group,12 animals per group.After modeling,drug injection was performed,and the Sham group and the Model group were injected with the same amount of normal saline.After the administration,the neurological function of the rats in each group was evaluated by the NDS(neurological deficit scale).HE staining was used to observe the pathological changes of the brain tissue of the rats in each group.RT-qPCR method was used to determine the expression levels of let-7a,Fas and FasL mRNA in the brain tissue of rats in each group;Western blot was used to determine the expression of Fas/FasL signaling pathway and apoptosis-related proteins in the brain tissue of rats in each group;TUNEL staining was used to detect the apoptosis rate in the brain tissue of rats in each group;the targeting relationship between let-7a and Fas and FasL was detected by dual-luciferase reporter gene assay.Compared with the Sham group,the NSD score,cell apoptosis rate,the mRNA expression level of Fas and FasL,and the protein expression level of Fas,FasL,Bax and Caspase-3 in the Model group were obviously increased(P<0.05);the brain tissue pathological damage was serious.Compared with the Model group,there was no obvious difference in the indicators of the rats in the NC agomir group(P>0.05);the NSD score,apoptosis of brain tissue and the expression level of Fas and FasL were obviously decreased in let-7a agomir group(P<0.05),and the pathological damage was alleviated to some extent.Fas activator attenuated the inhibitory effect of overexpression of let-7a on apoptosis of brain tissue in hypoxicischemic neonatal rats(P<0.05).There was a targeting relationship between let-7a and Fas,FasL.let-7a may reduce the cell apoptosis of hypoxic-ischemic neonatal rat brain tissue by inhibiting Fas/FasL.