Luo Ziwei, Xie Jinqi, Ye Haoxiang, Zhang Jie, Liu Yangping, Ma Chunmei, Cao Jiahui, Pan Hao, Liu Xiaosheng, Zhou Xianxi, Kong Jiechen, Chen Dongfeng, Liu Aijun
Traditional Chinese Medicine Innovation Research Center, Shenzhen Hospital of Integrated Traditional Chinese and Western Medicine, Shenzhen, P.R. China.
Research Centre of Basic Integrative Medicine, School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, P.R. China.
Cartilage. 2023 Nov 24:19476035231207778. doi: 10.1177/19476035231207778.
MicroRNAs (miRNAs) play a key role in the differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) into chondrocytes. Our previous study found that novel-miR-81 can relieve osteoarthritis, but its role in chondrogenic differentiation of BMSCs remains unclear. The purpose of this study was to explore the role of novel-miR-81 in chondrogenic differentiation of BMSCs.
We used a model in which transforming growth factor (TGF)-β3-induced BMSCs differentiation into chondrocytes. We detected the expression Sox9, Collagen Ⅱ, Aggrecan, novel-miR-81, and Rac2 by real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Western blot was performed to detect the expression of Sox9, Collagen Ⅱ, and Rac2. Dual-luciferase reporter gene assay confirmed that the association between novel-miR-81 and Rac2. In addition, the ectopic chondrocyte differentiation of BMSCs was performed subcutaneously in nude mice. The effect of novel-miR-81 and Rac2 on ectopic chondrogenic differentiation of BMSCs was determined by immunohistochemical staining.
Novel-miR-81 upregulated in chondrogenic differentiation of BMSCs. Rac2 was a key target of novel-miR-81. Mimic novel-miR-81 and siRac2 upregulated the expression of Sox9, Collagen Ⅱ, and Aggrecan.
Novel-miR-81 promotes the chondrocytes differentiation of BMSCs by inhibiting the expression of target gene Rac2, which provides potential targets for BMSCs transplantation to repair cartilage defects.
微小RNA（miRNA）在骨髓间充质干细胞（BMSC）向软骨细胞分化过程中起关键作用。我们之前的研究发现新型miR-81可缓解骨关节炎，但其在BMSC软骨形成分化中的作用仍不清楚。本研究旨在探讨新型miR-81在BMSC软骨形成分化中的作用。
我们使用转化生长因子（TGF）-β3诱导BMSC分化为软骨细胞的模型。通过实时逆转录定量聚合酶链反应（RT-qPCR）检测Sox9、Ⅱ型胶原蛋白、聚集蛋白聚糖、新型miR-81和Rac2的表达。进行蛋白质免疫印迹法检测Sox9、Ⅱ型胶原蛋白和Rac2的表达。双荧光素酶报告基因检测证实新型miR-81与Rac2之间的关联。此外，在裸鼠皮下进行BMSC的异位软骨细胞分化。通过免疫组织化学染色确定新型miR-81和Rac2对BMSC异位软骨形成分化的影响。
新型miR-81在BMSC软骨形成分化中上调。Rac2是新型miR-81的关键靶点。模拟新型miR-81和siRac2上调Sox9、Ⅱ型胶原蛋白和聚集蛋白聚糖的表达。
新型miR-81通过抑制靶基因Rac2的表达促进BMSC向软骨细胞分化，这为BMSC移植修复软骨缺损提供了潜在靶点。
