中文摘要：

目的：研究年龄相关microRNA-486-5p（miR-486-5p）对人骨髓间充质干细胞（h MSCs）衰老的调控作用。方法：通过microRNA芯片和real-time PCR检测供体年龄对h MSCs中miR-486-5p表达的影响;通过转染miR-486-5p模拟物或抑制物,过表达miR-486-5p或抑制其表达;用β-半乳糖苷酶染色检测miR-486-5p对h MSCs衰老的影响;通过siRNA研究沉默信息调节因子1（SIRT1）对h MSCs端粒酶逆转录酶（TERT）、端粒酶活性及衰老的影响。结果：随供体年龄增加,h MSCs中miR-486-5p的表达增加。过表达miR-486-5p可促进h MSCs衰老。相反,抑制miR-486-5p的表达可减少h MSCs的衰老。SIRT1及TERT随供体年龄增加而表达下降,直接抑制SIRT1的表达可减少TERT表达,抑制端粒酶活性,促进细胞衰老。同时抑制miR-486-5p和SIRT1的表达,使miR-486-5p失去对h MSCs端粒酶活性及衰老的调控作用。结论：miR-486-5p通过抑制SIRT1,减少h MSCs端粒酶活性,促进h MSCs衰老。

英文摘要：

AIM：To investigate the effects of microRNA-486-5p （miR-486-5p） on the senescence of human mesenchymal stem cells （ hMSCs）.METHODS： The expression of miR-486-5p was determined by miRNA arrays and real-time PCR.By transfection of miR-486-5p mimic or inhibitor, up-regulation or down-regulation of miR-486-5p expres-sion in hMSCs was established.The effect of miR-486-5p and silence information regulator 1 （SIRT1） on hMSC telomerase activity and senescence were detected byβ-galactosidase staining.RESULTS：The expression of miR-486-5p was up-regu-lated in the old hMSCs compared with the young hMSCs.Up-regulation of miR-486-5p resulted in increasing senescence of hMSCs.Conversely, down-regulation of miR-486-5p resulted in decreasing cell senescence.The expression of SIRT1 and telomerase reverse transcriptase （ TERT） was down-regulated in the old hMSCs compared with the young hMSCs.Directly repression of SIRT1 expression inhibited the hMSC TERT protein expression and telomerase activity, but increased cell se-nescence.The regulation of miR-486-5p on hMSC senescence was attenuated by inhibiting the expression of miR-486-5p and SIRT1 together.CONCLUSION：miR-486-5p enhances senescence of hMSCs by decreasing the expression of SIRT1 and telomerase activity.