MicroRNA-145调节骨关节炎软骨胞外基质代谢失衡的作用及机制研究

项目名称： MicroRNA-145调节骨关节炎软骨胞外基质代谢失衡的作用及机制研究

项目编号： No.81201431

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 医学四处

项目作者： 杨波

作者单位： 中国人民解放军第三军医大学

项目金额： 23万元

中文摘要： 关节软骨细胞外基质（ECM）代谢失衡是导致骨关节炎（OA）软骨退变的重要原因之一。我们发现OA关节软骨细胞中miR-145表达上调，抑制其能促进OA样软骨细胞表达特征型ECM基因，提示其参与调控OA关节软骨ECM代谢失衡，但机制不明。在证实miR-145调控Sox9蛋白表达的基础上，基于Sox9的辅激活因子Smad3是miR-145预测靶基因，且Smad3与OA病程进展相关，推测miR-145通过调节Sox9蛋白表达，同时经Smad3调节Sox9与靶基因的结合，参与调控OA关节软骨ECM代谢。拟通过双荧光素酶、原位杂交明确Smad3是miR-145靶基因；在体小鼠OA模型和离体细胞中干预miR-145表达，观察其对Sox9、Smad3、关节软骨ECM代谢和OA病程的影响，免疫共沉淀明确其参与Smad3介导Sox9与靶基因的结合的机制，阐明上述假说。本研究将为OA病因学和临床治疗提供新线索。

中文关键词： microRNA；骨关节炎；胞外基质；关节软骨；代谢

英文摘要： Osteoarthritis (OA) is a progressive disease of the joints characterized by degradation of articular cartilage. Although disease initiation may be multi-factorial, the cartilage destruction appears to be a result of the failure of the chondrocytes to maintain a balance between extracellular matrix (ECM) anabolism and catabolism. However, the molecular mechanisms involved in OA remain unclear. In previous study, we found that microRNA-145 was significantly up-regulated in OA cartilage by quantitative PCR. To investigate the function of miR-145 in OA cartilage, we performed the loss of miR-145 function study to examine whether the expression of the OA-related genes regulated by miR-145, when chondrocytes were stimulated with IL-1β. The results showed that the expression of MMP-13 and ADAMTS-5 with IL-1β stimulation was significantly reduced by anti-miR-145. Conversely, the expression of Aggrecan , Col2a1 and COMP was significantly increased. The results suggest that miR-145 plays an important role in regulating the balance between anabolism and catabolism of ECM. Sox9 and Smad3, as an essential co-activator of Sox9, are both important factors in OA pathogenesis. Based on our previous study that miR-145 directly regulates Sox9 expression on protein level and Smad3 is also a potential target of miR-145, we propose a

英文关键词： microRNA；Osteoarthritis；extracellular matrix；articular cartilage；metabolism