微小RNA-449a对骨髓间充质干细胞向神经元样细胞分化的影响  

Effect of miR-449a on differentiation of bone marrow mesenchymal stem cells into neuron-like cells

作　　者：王洪娇 周洁信[1] 母玉元 梁春明[1] 邸辞寒 Wang Hongjiao;Zhou Jiexin;Mu Yuyuan;Liang Chunming;Di Cihan(Department of Neurology,Second Affiliated Hospital of Qiqihar Medical College,Qiqihaer 161200,Heilongjiang Province,China)

机构地区：[1]齐齐哈尔医学院附属第二医院神经内科,161200

出　　处：《中华老年心脑血管病杂志》2020年第7期757-761,共5页Chinese Journal of Geriatric Heart,Brain and Vessel Diseases

摘　　要：目的探究微小RNA(microRNA,miR)-449a通过靶向Notch1调节自噬对骨髓间充质干细胞(bone mesenchymal stem cell,BMSC)向神经元样细胞分化的机制。方法人BMSC分为对照组、miR-449a类似物(mimic)组、mimic+Notch1组和Notch1组。通过质粒转染过表达miR-449a和(或)Notch1。qPCR检测miR-449a和Notch1 mRNA。免疫荧光染色检测神经元特异性烯醇化酶(neuron-specific enolase,NSE),并分析BMSC向神经元样细胞分化情况。Western blot检测Notch胞内结构域(NICD)、酵母ATG6同源物(Beclin1)蛋白水平。结果与对照组比较,mimic组Notch1 mRNA及蛋白表达明显降低,差异有统计学意义(P<0.05)。与mimic组比较,mimic+Notch1组Notch1 mRNA及蛋白表达明显升高,差异有统计学意义(P<0.05)。与对照组比较,mimic组NSE和微管相关蛋白2水平明显升高,Notch1组NSE和微管相关蛋白2水平明显降低,差异有统计学意义(P<0.05)。与mimic组比较,mimic+Notch1组NSE和微管相关蛋白2水平明显降低,差异有统计学意义(P<0.05)。与对照组比较,mimic组NICD和Beclin1水平明显降低,Notch1组NICD和Beclin1水平明显升高,差异有统计学意义(P<0.05)。与mimic组比较,mimic+Notch1组NICD和Beclin1水平明显升高(1.17±0.12 vs 0.92±0.07,2.38±0.25 vs 1.21±0.11,P<0.05)。结论上调BMSC中miR-449a会通过下调Notch1相关通路抑制自噬,促进神经元标志蛋白NSE和微管相关蛋白2表达,使BMSC向神经元样细胞分化。Objective To study the mechanism of microRNA(miR)-449 a underlying the differen-tiation of Notch 1-targeted bone marrow mesenchymal stem cells(BMSC)into neuron-like cells by regulating their autophagy.Methods Human BMSC were divided into control group,miR-449 a mimic group,miR-449 a mimic+Notch 1 group,and Notch-1 group.The plasmid-transfected miR-449 a and/or Notch 1 were overexpressed.The expressions of miR-449 a and Notch 1 mRNA and protein were detected by RT-qPCR.The neuron specific enolase(NSE)was detected with immunofluorescence staining.The differentiation of BMSC into neuron-like cells was analyzed.The serum Notch 1 intracellular domain(NICD)and Beclin 1 protein levels were measured by Western blot.Results The expression levels of Notch 1 mRNA and protein were significantly lower in miR-449 a mimic group than in control group(P<0.05)and significantly higher in miR-449 a mimic+Notch 1 group than in miR-449 a mimic group(P<0.05).The serum levels of NSE and MAP-2 were significantly higher in miR-449 a mimic group than in control group and significantly lower in Notch 1 group than in control group and in miR-449 a mimic+Notch 1 group than in miR-449 a mimic group(P<0.05).The serum levels of NSE and MAP-2 were significantly lower in miR-449 a mimic group than in control group while those of NICD and Beclin 1 were significantly higher in Notch 1 group than in control group(P<0.05)and in miR-449 a mimic+Notch 1 group than in miR-449 a mimic group(1.17±0.12 vs 0.92±0.07,2.38±0.25 vs 1.21±0.11,P<0.05).Conclusion Upregulated miR-449 a in BMSC can inhibit their autophagy by downregulating the Notch 1-related signaling pathway,promote the expressions of NSE and MAP-2,thus simulating the differentiation of BMSC into neuron-like cells.

关 键 词：微RNAS 间充质基质细胞 神经元 细胞分化 自噬 微管相关蛋白质类 

分 类 号：R329.2[医药卫生—人体解剖和组织胚胎学]