摘要
目的探究过表达miR-27a对急性脑梗死大鼠海马神经元损伤的影响及可能机制。方法将60只SD大鼠随机分为假手术组(Sham组)、模型组(Model组)、Agomir阴性对照组(Agomir-NC组)和miR-27a agomir组(Agomir组),每组15只。采用改良Longa线栓法构建急性脑梗死大鼠模型,于造模前1天和造模成功时,分别经侧脑室注射15 mg/kg的agomir-NC或miR-27a agomir。术后72 h,采用Zea-Longa评分法对大鼠神经功能缺损进行评分;采用氯化三苯基四氮唑染色法(TTC)测量大鼠脑梗死面积;原位缺口末端标记法(TUNEL)检测大鼠海马组织细胞凋亡水平;qRT-PCR法检测各组大鼠海马组织miR-27a的表达水平;流式细胞术(FCM)检测各组大鼠海马组织中Iba-1^(+)/CD68^(+)小胶质细胞所占百分比;酶联免疫吸附实验(ELISA)检测各组大鼠海马组织IL-1β、IL-6、TNF-α及iNOS的表达水平;Western blotting检测大鼠海马组织中TLR4信号通路相关蛋白TLR4、MyD88、p-NF-κB p65及NF-κB p65表达情况。结果与Sham组相比,Model组大鼠海马组织细胞凋亡水平及Iba-1^(+)/CD68^(+)小胶质细胞水平均显著增加(均P<0.001),海马组织中IL-1β、IL-6、TNF-α水平和iNOS活性及TLR4、MyD88、p-NF-κB p65蛋白表达水平均显著升高(P<0.05),海马组织中miR-27a表达水平显著降低(P<0.001)。与Model组比,Agomir组大鼠神经功能缺损评分、脑梗死面积、海马组织细胞凋亡水平及Iba-1^(+)/CD68^(+)小胶质细胞水平均显著降低(均P<0.001),海马组织中IL-1β、IL-6、TNF-α水平和iNOS活性及TLR4、MyD88、p-NF-κB p65蛋白表达水平均显著下降(P<0.05),海马组织miR-27a表达水平显著上升(P<0.001)。结论过表达miR-27a通过抑制小胶质细胞M1型极化减轻急性脑梗死大鼠海马神经元损伤,其机制可能与抑制TLR4/NF-κB信号通路活化有关。
Objective To investigate the effects of miR-27 a overexpression on hippocampal neuron injury in rats with acute cerebral infarction(ACI)and its possible mechanism.Methods A total of 60 SD rats were randomly divided into sham operation group(Sham group),Model group,agomir negative control group(Agomir-NC group)and miR-27 a agomir group(Agomir group),with 15 rats in each group.Modified Longa thread embolization method was used to establish the rat models of ACI.One day before modeling and the time when modeling was successful,15 mg/kg agomir-NC or miR-27 a agomir were injected through the lateral ventricle.The neurological deficits of rats were evaluated with Zea-Longa score 72 h after operation.The cerebral infarct size of rats was measured with triphenyltetrazole chloride(TTC)staining.The apoptosis level of hippocampal tissue was detected with TUNEL.The expression of miR-27 a in the hippocampus was detected with qRT-PCR.The percentage of Iba-1^(+)/CD68^(+)microglia in the hippocampus was detected with flow cytometry(FCM).The levels of IL-1β,IL-6,TNF-αand iNOS in hippocampus were detected with enzyme-linked immunosorbent assay(ELISA).The expressions of toll-like receptor 4(TLR4)signaling pathway related proteins including TLR4,MyD88,p-NF-κB p65 and NF-κB p65 in hippocampus were detected with Western blotting.Results Compared with Sham group,the Model group had significantly increased apoptosis of hippocampal cells and level of Iba-1^(+)/CD68^(+)microglia(P<0.001),and significantly increased levels of IL-1β,IL-6,TNF-αand iNOS and protein expressions of TLR4,MyD88 and p-NF-κB p65(P<0.05),but significantly decreased expression of miR-27 a(P<0.001).Compared with Model group,the agomir group had significantly decreased neurological deficits score,cerebral infarction area,apoptosis level of hippocampal cells and level of Iba-1^(+)/CD68^(+)microglia(P<0.001),and significantly decreased levels of IL-1β,IL-6,TNF-αand iNOS and protein expressions of TLR4,MyD88 and p-NF-κB p65(P<0.05),but significantly increased ex
作者
邹品衡
陈添果
胡康
李伟才
ZOU Pinheng;CHEN Tianguo;HU Kang;LI Weicai(Department of Clinical Laboratory,The Third Affiliated Hospital of Hengyang Medical College,University of South China,Hengyang 421900,Hunan,China;Department of Internal Medicine-Neurology,The Third Affiliated Hospital of Hengyang Medical College,University of South China,Hengyang 421900,Hunan,China;Department of Emergency,The Third Affiliated Hospital of Hengyang Medical College,University of South China,Hengyang 421900,Hunan,China)
出处
《山东大学学报（医学版）》
CAS
北大核心
2022年第9期59-66,共8页
Journal of Shandong University:Health Sciences
基金
湖南省教育厅科学研究项目(20C1596)
衡阳市科技局指导性项目(2020jh042741)
