%A Ma Zetao, Zeng Hui, Wang Deli, Weng Jian, Feng Song %T MicroRNA-138-5p regulates chondrocyte proliferation and autophagy %0 Journal Article %D 2021 %J Chinese Journal of Tissue Engineering Research %R 10.3969/j.issn.2095-4344.2997 %P 674-678 %V 25 %N 5 %U {https://www.cjter.com/CN/abstract/article_16199.shtml} %8 2021-02-18 %X BACKGROUND: Abnormal autophagy in chondrocytes often leads to cartilage degeneration, thereby triggering osteoarthritis. Recent studies have found that microRNAs play an important role in chondrocyte autophagy; however, the molecular mechanism is yet unclear. 
OBJECTIVE: To investigate the role of microRNA-138-5p (miR-138-5p) in the regulation of chondrocyte proliferation and autophagy activities, and to reveal its mechanisms. 
METHODS: Chondrosarcoma cell line SW1353 were cultured in vitro and transfected with negative control miRNA or miR-138-5p mimic. Cell proliferation activity was measured by cell counting kit-8 assay, the expression of matrix metalloproteinases 1, 3, and 13 mRNA was measured by fluorogenic quantitative PCR. The endogenous LC3 subcellular location was detected by immunofluorescence staining. The miR-138-5p and SIRTI mRNA target sites were predicted using TargetScan 7.1 online tool. Autophagy-related proteins and AMPK signal proteins were detected by immunoblotting assay. 
RESULTS AND CONCLUSION: Cells transfected with miR-138-5p mimic, compared with those transfected with negative control miRNA, showed lower proliferation activity, less LC3 puncta, and reduced expression of SIRT1, LC3-II, p-AMPK, but increased protein expression of p62 and increased mRNA expression of matrix metalloproteinases 1, 3, 13. There was a conserved miR-138-5p binding site in the 3’UTR region of SIRT1 mRNA. To conclude, miR-138-5p regulates SW1353 cell autophagy and proliferation through the SIRT1/AMPK signaling pathway. The up-regulated expression of miR-138-5p promotes the secretion of matrix metalloproteinases from chondrocytes, indicating that miR-138-5p plays an important role in the progression of osteoarthritis.