基于MicroRNA右归饮促骨髓间充质干细胞成软骨分化机理及联合组织工程修复关节软骨缺损的研究

Repairing articular cartilage defect is one of the difficult problems of medicine and tissue engineering opens a new way for it. Bone marrow mesenchymal stem cells ( BMSCs ) have been proposed as the ideal seed cells for cartilage tissue engineering. How to regulate the chondrogenic differentiation of BMSCs is the primary problem of cartilage tissue engineering，and little is known about it. MicroRNAs，a class of non coding RNA that regulate the gene expression at the post transcription levels, have been found playing an important role in the differentiation of stem cells , but there is little study on regulation of chondrogenic differentiation of BMSCs. Our previous study found that tonifying kidney herbs Yougui Yin could promote the differentiation and proliferation of BMSCs to cartilage cell，but the mechanism remains unknown. The main purpose of this project is to study the miRNA regulation mechanism of chondrogenic differentiation of mesenchymal stem cells，and find target of Yougui Yin by using miRNAarray and tissue engineering technology. The results will be confirmed by experiment on repairing rat articular cartilage defects combined bone marrow mesenchymal stem cells gel complex with YouguiYin. This study is promised to gain new understanding and breakthrough of molecular mechanism about chondrogenic differentiation of MSCs，and to provide reliable theoretical basis of treatment of cartilage defects for TCM.

软骨缺损修复是医学难题之一，组织工程开辟了新的途径。骨髓间充质干细胞（BMSCs）被认为是软骨组织工程理想的种子细胞。如何调控BMSCs成软骨分化是软骨组织工程的首要问题。然而目前分化调控机制还不完全清楚。miRNA是一类具有基因调控功能的小RNA，近年研究发现miRNA在干细胞的干性维持及分化中具有重要的功能，但关于miRNA调控BMSCs成软骨分化机制的研究较少，miRNA在这一细胞事件中扮演着怎样的角色亟待我们去探索。我们前期研究发现，补肾中药右归饮可促进BMSCs向软骨细胞分化与增殖，但机理不明。本项目拟采用miRNA芯片、组织工程等技术，探讨miRNA在BMSCs成软骨分化中的调控机制及右归饮的作用靶点，并以右归饮联合BMSCs-藻酸盐凝胶修复关节软骨缺损实验加以验证。本研究可望在阐释BMSCs成软骨分化的分子机制方面取得新的认识和突破，为中医药治疗软骨缺损提供可靠的理论依据。

软骨缺损修复是医学难题之一，中医药及组织工程技术开辟了新的途径，项目组前期研究发现补肾中药右归饮可促进BMSCs向软骨细胞分化与增殖，但机理不明；同时与BMSCs联合治疗兔软骨缺损有良好的疗效。MiRNA在干细胞分化中扮演着重要角色，但右归饮促进BMSCs成软骨分化过程中，miRNA的调控机制研究甚少。本项目利用右归饮含药血清干预BMSCs，证实右归饮含药血清能促进TGF-β1诱导的BMSCs成软骨细胞分化，并通过miRNA芯片检测及生物信息学分析发现，右归饮含药血清能上调17个microRNA，下调2个microRNA；其中miR-24-3p、MAPK信号通路及MAPK13、MAPK14、TRAF6、MAP3K7基因被预测为关键microRNA、信号通路及靶基因。右归饮含药血清可能通过上调miR-24-3p阻断MAPK信号通路促进BMSCs成软骨分化；同时，利用组织工程技术实验证实右归饮联合骨髓间充质干细胞-藻酸盐复合体治疗软骨缺损的治疗效果明显，本项目的研究成果是对软骨缺损修复提供了新的认识和突破，也为中医药治疗软骨缺损提供新的实验依据和思路。