Circ_0062582 promotes osteogenic differentiation of human bone marrow mesenchymal stem cells in vitro by elevating SMAD5 expression through sponging miR-197-3p

Circular RNAs (circRNAs) play crucial roles in many human diseases. However, the functions of circRNAs in osteoporosis (OP) are barely reported. In this study, we aimed to explore the function of circ_0062582 in osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) in vitro. Circ_0062582 and SMAD5 were downregulated and miR-197-3p was upregulated in OP patients and increased in osteoblast medium (OM)-induced hBMSCs in vitro. Circ_0062582 knockdown inhibited the viability and osteogenic differentiation of hBMSCs. Circ_0062582 directly targeted miR-197-3p and miR-197-3p inhibition reversed the effects of circ_0062582 on hBMSC viability and osteogenic differentiation. SMAD5 was the target gene of miR-197-3p. SMAD5 overexpression promoted the viability and osteogenic differentiation of hBMSCs and attenuated miR-197-3p-mediated suppressive roles in hBMSC viability and osteogenic differentiation. In conclusion, circ_0062582 sponged miR-197-3p to elevate SMAD5 expression, thereby inducing hBMSC proliferation and osteogenic differentiation in vitro.