miR-148a促进人诱导性多能干细胞向心肌样细胞的分化

文题释义：人诱导性多能干细胞来源的心肌样细胞：在体外直接将人诱导性多能干细胞定向诱导分化为心肌样细胞具有供者个体基因的特异性，不仅可以进行发病机制的深入研究，还可以进行个体化药物治疗测试，为精准个性化治疗带来希望。来自于患者自身体细胞的心肌细胞扩增速度快，没有免疫排斥和伦理问题，但目前的主要问题是来自于人诱导性多能干细胞的心肌样细胞成熟程度不佳，分化的细胞不具备成人心肌细胞的电生理活动，且纯化有一定困难。微小RNA的调节作用：微小RNA是一类内源性的非编码单链RNA，通常含有19-22个核苷酸，可通过靶向结合mRNA而使其降解或抑制其翻译，发挥对靶基因的转录后调控作用。近年来，基于芯片分析技术发现有多个miRNA在心肌分化发育或干细胞向心肌样细胞定向分化过程中发挥调控作用，有正向调控也有负向调控。背景：研究发现，miR-148a可以促进人骨髓间充质干细胞定向分化为成熟心肌样细胞，但关于miR-148a对人诱导性多能干细胞向心肌样细胞分化的影响则未见报道。目的：探讨miR-148a对人诱导性多能干细胞向心肌样细胞分化的影响。方法：将人诱导性多能干细胞分为3组向心肌样细胞诱导分化，对照组细胞不做处理，低表达组细胞用miR-148a抑制物处理28 d，高表达组细胞用miR-148a模拟物处理28 d；另取常规培养28 d的人诱导性多能干细胞为空白对照组。CCK-8检测细胞增殖活力，qRT-PCR检测miR-148amRNA的表达，免疫荧光染色和Western blot检测MHC和cTnT蛋白的表达。结果与结论：①低表达组细胞内miR-148a mRNA表达、细胞增殖活力低于空白对照组和对照组，高表达组高于其他3组(P < 0.01)；②空白对照组无MHC和cTnT的阳性表达，对照组、低表达组和高表达组均有MHC和cTnT的阳性表达；③低表达组细胞MHC和cTnT蛋白表达低于对照组，高表达组高于其他3组(P < 0.01)；④以上结果提示，miR-148a可促进人诱导性多能干细胞向心肌样细胞分化。ORCID: 0000-0003-1698-4393(毛庆)中国组织工程研究杂志出版内容重点：干细胞；骨髓干细胞；造血干细胞；脂肪干细胞；肿瘤干细胞；胚胎干细胞；脐带脐血干细胞；干细胞诱导；干细胞分化；组织工程

miRNA-148a promotes the differentiation of human induced pluripotent stem cells into cardiomyocyte-like cells

BACKGROUND:Studies have shown that miRNA-148a can promote human bone marrow mesenchymal stem cells to differentiate into mature cardiomyocyte-like cells,but the effect of miRNA-148a on the differentiation of human induced pluripotent stem cells into cardiomyocyte-like cells has not been reported.OBJECTIVE:To investigate the effect of miRNA-148a on the differentiation of human induced pluripotent stem cells into cardiomyocyte-like cells.METHODS:Human induced pluripotent stem cells differentiating into cardiomyocyte-like cells were divided into three groups.Cells in the control group were not treated.Cells in the low expression group were treated with miRNA-148a for 28 days,and those in the high expression group were treated with mimics of miRNA-148a for 28 days.In addition,human induced pluripotent stem cells cultured for 28 days were taken as the blank control group.CCK-8 was used to detect cell proliferation activity.qRT-PCR was used to detect the expression of miRNA-148a.Immunofluorescence staining and western blot analysis were performed to detect the expression of MHC and cTnT protein.RESULTS AND CONCLUSION:The expression of intracellular miR-148a mRNA and cell proliferation activity in the low expression group were lower than those in the blank control and control groups,while those in the high expression group were significantly higher than those in the other three groups(P<0.01).There were no positive expression of MHC and cTnT in the blank control group.There were positive expressions of MHC and cTnT in the control,low expression and high expression groups.The expression of MHC and cTnT protein in the low expression group was significantly lower than that in the control group,and that in the high expression group was significantly higher than that in the other three groups(P<0.01).These results suggest that miRNA-148a can promote the differentiation of human induced pluripotent stem cells into cardiomyocyte-like cells.