靶向JAG1调控ESCs分化促进DM慢性创面愈合的研究

Abnormal proliferation and differentiation of epidermal stem cells (ESCs) is the main reason for delayed healing in diabetes mellitus(DM) chronic wound. In our prophase study, Jagged1(JAG1) is involved in the regulation of proliferation and differentiation of ESCs which is similar to other studies. However, concrete details of JAG1 responsible for the action of ESCs and mechanisms in regulation of wound healing process are not completely clear. This study is to observe spatial and temporal changes of JAG1 and Notch acceptor expression; to investigate the relationship of the above and relative repair gene during the process of DM wound healing in vivo and in vitro; to intervene JAG1 expression and to observe the effect of the overexpression and downregulation of JAG1 to the proliferation, differentiation, adhesion and migration of ESCs and DM wound repair on the GOF/LOF strategies of transfection; to establish JAG1 transgenic mice model by microinjection and to test the effect of JAG1 to DM wound healing in transgenic mice and further elucidate the related mechanism of JAG1 in regulation of action of ESCs and wound repair in diabetic mice. We hope our effort can provide new theoretical basis and new target for the treatment of DM chronic wound by intervening JAG1 mediated Notch signaling pathway.

表皮干细胞（ESCs）的增殖和分化异常是糖尿病（DM）患者伤口不愈的重要原因。文献和我们前期研究发现Jagged1(JAG1)参与ESCs增殖分化的调控，但对于JAG1如何调控ESCs的增殖和分化，继而影响DM创面愈合的机制仍然不清楚。本项目拟在体皮肤和离体模型系统研究DM创面愈合过程中JAG1及受体Notch的时空表达和修复相关基因的相互关系；GOF/LOF干预策略研究过表达或敲低JAG1对ESCs增殖、分化、黏附与迁移能力的变化及对创面愈合的影响作用；受精卵显微注射法构建JAG1表达功能型和缺失型的转基因小鼠，在体验证JAG1对转基因DM小鼠创面愈合的影响，阐明JAG1调控ESCs增殖分化和DM创面愈合的机制，为临床探索通过干预JAG1介导的Notch信号治疗DM创面提供理论基础和新靶点。

慢性难愈性创面是糖尿病的主要并发症之一。表皮干细胞（ESCs）的增殖和分化异常是糖尿病（DM）患者伤口不愈的重要原因。文献和我们前期研究发现Jagged1(JAG1)参与ESCs增殖分化的调控，但对于JAG1如何调控ESCs的增殖和分化，继而影响DM创面愈合的机制仍然不清楚。本项目在体皮肤和离体模型系统研究DM创面愈合过程中JAG1及受体Notch的时空表达和修复相关基因的相互关系；GOF/LOF干预策略研究过表达或敲低JAG1对ESCs增殖、分化、黏附与迁移能力的变化及对创面愈合的影响作用；构建JAG1表达功能型和缺失型的转基因小鼠，在体验证JAG1对转基因DM小鼠创面愈合的影响。研究发现，在糖尿病小鼠创面边缘，Notch信号通路的JAG1配体、Notch1受体和Notch靶基因增强子Hes1的蛋白及mRNA水平均显著升高；此外，我们也观察到JAG1在ESCs高表达。在体外实验中我们发现，JAG1过表达能促进ESCs迁移，而JAG1基因敲除后ESCs迁移能力显著降低。进一步在体实验研究也发现JAG1过表达的表皮干细胞能促进糖尿病创面的愈合。这些结果为表皮干细胞可能通过Notch信号通路促进糖尿病创面愈合提供了证据，阐明JAG1调控ESCs增殖分化和DM创面愈合的机制，为临床探索通过干预JAG1介导的Notch信号治疗DM创面提供理论基础和新靶点。