miR-1307-3p suppresses the chondrogenic differentiation of human adipose-derived stem cells by targeting BMPR2

MicroRNAs (miRs) are involved in several physiological processes, including chondrogenic differentiation, however, their expression and roles in the chondrogenic differentiation of human adipose-derived stem cells (hADSCs) remain to be fully elucidated to date. Our previous study showed that miR-1307-3p was significantly downregulated during chondrogenic differentiation by microarray and northern blot analysis. The present study aimed to investigate the effects of miR-1307-3p on chondrogenic differentiation and the underlying mechanisms. First, the decreased expression of miR-1307-3p was confirmed by reverse transcription-quantitative polymerase chain reaction analysis. Subsequently, gain- and loss-of-function of miR-1307-3p experiments showed that the overexpression of miR-1307-3p suppressed the deposition of cartilage matrix proteoglycans and decreased the expression of cartilage-related markers, including sex determining region Y-box 9, collagen type II α1 chain and aggrecan, whereas the knockdown of miR-1307-3p had the opposite effect. In addition, bone morphogenetic protein receptor type 2 (BMPR2) was identified as a target of miR-1307-3p. Further mechanistic investigations showed that miR-1307-3p attenuated the chondrogenic differentiation of hADSCs at least partly by inhibiting BMPR2-mothers against decapentaplegic signaling pathways. In conclusion, the findings revealed that miR-1307-3p inhibited the chondrogenic differentiation of hADSCs by targeting BMPR2 and its down-stream signaling pathway, which may provide novel therapeutic clues for the treatment of cartilage injury.