miR-31-5p靶向Notch1调节骨关节炎软骨细胞增殖和凋亡的作用

目的明确miR-31-5p在骨关节炎软骨细胞中的作用。方法采用Hulth法进行大鼠骨关节炎造模,并分离原代软骨细胞,白细胞介素(interleukin,IL)-1β诱导体外模型,检测miR-31-5p的表达变化;进一步通过在线数据库预测miR-31-5p靶点并验证,细胞增殖检测试剂盒(cell counting kit-8,CCK-8)和流式细胞术检测miR-31-5p对原代软骨细胞增殖和凋亡的影响。结果骨关节炎大鼠中miR-31-5p表达下调;miR-31-5p mimics促进软骨细胞增殖,而miR-31-5p inhibitor诱导软骨细胞凋亡增加;此外,miR-31-5p inhibitor促进IL-6和基质金属蛋白酶13(matrix metalloprotein,MMP-13)表达增加;荧光素酶报告基因实验证实Notch1是miR-31-5p的直接靶点,Notch1过表达质粒会部分抵消miR-31-5p mimics对软骨细胞的增殖保护作用。结论miR-31-5p下调表达介导骨关节炎软骨细胞增殖受限和凋亡发生,可能参与骨关节炎的发病。

Effects of miR-31-5p on Proliferation and Apoptosis of Osteoarthritis Chondrocytes by Targeting Notch1

Objective To identify the effects of miR-31-5p on osteoarthritis chondrocytes.Methods Osteoarthritis models of rats were established according to Hulth method,and primary chondrocytes were isolated and treated by interleukin 1β(IL-1β).The expression of miR-31-5p was evaluated by qRT-PCR.The potential target of miR-31-5p was predicted by TargetScanHuman database,and verified by luciferase reporter assay.Effects of miR-31-5p on proliferation and apoptosis of primary chondrocytes were determined by Cell Counting Kit-8(CCK-8)and Flow Cytometry.Results The expression of miR-31-5p was downregulated in osteoarthritis models of rats.miR-31-5p mimics promoted proliferation of chondrocytes,and miR-31-5p inhibitor led to apoptosis of chondrocytes.Moreover,miR-31-5p inhibitor promoted expression of IL-6 and matrix metalloprotein 13(MMP-13).Further investigation revealed Notch1 was the direct target of miR-31-5p,and Notch1 overexpression partially limited the protective role of miR-31-5p mimics in chondrocytes.Conclusion The downregulated miR-31-5p mediated apoptosis and limited proliferation of chondrocytes in osteoarthritis,which might contribute to pathogenesis of osteoarthritis.