let-7a通过抑制MAP4K3/MKK4/JNK信号通路减少脑出血大鼠神经元调亡  

let-7a inhibits MAP4K3/MKK4/JNK signaling pathway to decrease neu⁃ronal apoptosis in rats with intracerebral hemorrhage

作　　者：杨慧[1] 万广[2] 高绚照[1] 柳毅[1] 王守春[3] YANG Hui;WAN Guang;GAO Xuan-zhao;LIU Yi;WANG Shou-chun(Department of Neurology,Xinxiang Central Hospital,First Affiliated Hospital of Xinxiang Medical College,Xinxiang 53100,China;Department of Orthopedics,First Affiliated Hospital of Xinxiang Medical College,Xinxiang 53100,China;The First Hospital of Jilin University,Changchun 130000,China)

机构地区：[1]新乡市中心医院神经内科,河南新乡453100 [2]新乡医学院第一附属医院骨科,河南新乡453100 [3]吉林大学第一医院,吉林长春130000

出　　处：《中国病理生理杂志》2020年第6期1055-1062,共8页Chinese Journal of Pathophysiology

基　　金：河南省医学科技攻关计划项目(No.201602114)。

摘　　要：目的:研究微小RNA let-7a对脑出血(ICH)大鼠神经元凋亡的影响及其分子机制。方法:从48只健康SD大鼠中随机选取8只作为假手术组,将2μLⅦ型胶原酶注入其余大鼠苍白球以构建ICH模型。将造模后的大鼠随机分为模型(2μL生理盐水)组、let-7a激动剂(agomir)组、阴性对照(NC)agomir组、let-7a拮抗剂(antagomir)组和NC antagomir组,每组8只,在侧脑室注射相应药物。7 d后进行神经功能评分;HE染色观察病理损伤;RT-qPCR和Western blot检测相关蛋白表达水平;TUNEL染色检测神经元凋亡情况;利用生物信息学软件预测let-7a与丝裂原活化的蛋白激酶激酶激酶激酶3(MAP4K3)的靶向关系,并在HEK293T细胞中用双萤光素酶报告基因实验进一步验证。结果:动物实验中,let-7a过表达时,神经功能评分降低,病理损伤减轻,胶质细胞原纤维酸性蛋白(GFAP)低表达,神经元凋亡减少,cleaved caspase-3和cleaved PARP低表达(P<0. 05)。细胞实验中,MAP4K3是let-7a的靶基因之一,且两者为负向调控;let-7a过表达抑制MAP4K3/MKK4/JNK的表达。结论:let-7a通过抑制MAP4K3/MKK4/JNK信号通路,减少ICH大鼠神经元凋亡。AIM:To investigate the effect of microRNA let-7a on neuronal apoptosis in a rat model of intrace⁃rebral hemorrhage(ICH).METHODS:Forty-eight healthy SD rats were selected,8 of which served as sham group,and 2μL of type VII collagenase was injected into globus pallidus of the remaining rats to construct ICH model.These ICH rats were randomly divided into model(2μL normal saline)group,let-7a agomir group,NC agomir group,let-7a an⁃tagomir group and NC antagomir group,with 8 rats in each group,and the corresponding drugs were injected into the lateral ventricle.After 7 d,the neurological function scoring was performed,and HE staining was used to observe the pathological damage.RT-qPCR and Western blot were used to detect the expression of related proteins.TUNEL staining was used to detect neuronal apoptosis.The targeting relationship between let-7a and mitogen-activated protein kinase ki⁃nase kinase kinase 3(MAP4K3)was predicted by bioinfomatic software,and further verified by dual-luciferase reporter assay.RESULTS:In animal experiments,when let-7a was over-expressed,neurological function scores were reduced,and the pathological damage was alleviated.Glial fibrillary acidic protein(GFAP)expression was down-regulated,neuro⁃nal apoptosis was reduced,and the protein levels of cleaved caspase-3 and cleaved PARP were decreased(P<0.05).In cell assays,MAP4K3 was one of the target genes of let-7a,and MAP4K3 was negatively regulated by let-7a.let-7a overexpression inhibited the expression of MAP4K3/MKK4/JNK.CONCLUSION:let-7a reduces neuronal apoptosis in ICH rats by inhibiting the MAP4K3/MKK4/JNK signaling pathway.

关 键 词：脑出血 微小RNA let-7a MAP4K3/MKK4/JNK信号通路 神经元 细胞凋亡 

分 类 号：R743.34[医药卫生—神经病学与精神病学] R363.2[医药卫生—临床医学]