Pdx1激活Ngn3和Pax6诱导iPS细胞向胰岛β细胞分化的实验研究  

Study role of Pdx1 and its mechanism in activating Ngn3 and Pax6 to induce differentiation of iPSCs into islet β cells

作　　者：占小波 肖亮[2,3] 韩冬[1,2] 蒋经柱 赵杭芬 周汉新[1,2] 

机构地区：[1]广州医科大学,广东广州518082 [2]深圳市第二人民医院肝胆外科,广东深圳518035 [3]深圳市第二人民医院肿瘤生物治疗科,广东深圳518035

出　　处：《中国现代普通外科进展》2014年第8期589-593,共5页Chinese Journal of Current Advances in General Surgery

基　　金：深圳市战略性新兴产业发展专项资金项目(JCYJ20120614085530935);深圳市科技计划项目(医疗卫生类)

摘　　要：目的:探讨胰十二指肠同源盒基因-1(Pdx1)在诱导多潜能干细胞(i PSCs)分化为胰岛β细胞中的作用及其机制。方法:体外培养人皮肤成纤维细胞来源的i PSCs,将该i PSCs定向诱导分化20 d;RT-PCR检测胰岛素相关基因的表达情况;比较诱导前后几个重要转录因子的表达情况;Ch IP检测胰岛β细胞发育过程中最重要的转录因子Pdx1结合启动子区域的具体位点。结果:体外成功培养人皮肤来源的i PSCs;胰岛素相关基因Maf A、insulin、Glut2、Nkx6.1、Glucokinase和Tcf1均呈现不同程度的表达增强,并在第20 d时表达基本达到高峰;实验组转录因子Pdx1、Ngn3与Pax6表达较对照组明显增强;Pdx1通过结合Insulin-P、Ngn3-P、Pax6-P区域激活下游基因Ngn3和Pax6。结论:Pdx1激活下游基因Ngn3和Pax6可能是其促进i PSCs定向诱导分化为胰岛β细胞的机制之一。Objective：To investigate role of pancreatic and duodenal homeobox factor 1 （Pdx1）and its mechanism in differentiating induced pluripotent stem cell （iPSCs）into islet β cells.Methods：iPSCs deriving from human skin fibroblasts were cultured in vitro and directionally induced to differentiate for 20 days.The expression of insulin-related genes was detected by RT-PCR.Then,the expression of some important transcription factors,was compared before and after the differentiation process.Specific sites of the promoter regions which were combined with Pdx 1,the most pivotal transcription factor in the islet β cells development process,were detected by ChIP.Results：iPSCs deriving from human skin fibroblasts were cultured successfully in vitro.Insulin-related genes that were MafA,insulin,Glut2,Nkx6.1,Glucokinase and Tcf1 showed varying degrees of enhanced expression,and the expression almost reached a peak on the 20th day.The expression of transcription factors Pdx 1,Ngn 3 and Pax 6 in the experimental group was strengthened compared with that of control group.ChIP assay confirmed that Pdx1 activates the expression of the downstream transcription factors Ngn 3 and Pax 6 by combined with Insulin-P、Ngn3-P and Pax6-P.Conclusion：That Pdx1 activates downstream transcription factors Ngn 3 and Pax 6 may be one of the mechanisms that promotes directional inducing differentiation of iPSCs into islet β cells.

关 键 词：诱导多潜能干细胞 胰岛Β细胞 胰腺十二指肠同源盒基因1 神经元素3 成对盒基因6 胰岛素 

分 类 号：R329.26[医药卫生—人体解剖和组织胚胎学]