MicroRNA-23a-5p regulates osteogenic differentiation of human bone marrow-derived mesenchymal stem cells by targeting mitogen-activated protein kinase-13.

The molecular mechanisms of osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) remain to be fully elucidated. MicroRNAs (miRs) serve vital roles in the process of regulating osteogenic differentiation of BMSCs. The present study aimed to investigate the role of miR‑23a‑5p in osteogenic differentiation of human (h)BMSCs, and the underlying molecular mechanism. The results of reverse transcription‑quantitative polymerase chain reaction demonstrated that miR‑23a‑5p was significantly downregulated in the process of osteogenic differentiation. Upregulation of miR‑23a‑5p inhibited osteogenic differentiation of hBMSCs, and down‑regulated expression of miR‑23a‑5p enhanced this process, which was confirmed by alkaline phosphatase (ALP) and Alizarin Red S staining. A dual‑luciferase reporter assay confirmed that mitogen‑activated protein kinase 13 (MAPK13) was a direct target of miR‑23a‑5p. In addition, knockdown of MAPK13 inhibited osteogenic differentiation of hBMSCs, similar to the effect of upregulation of miR‑23a‑5p. Finally, the knockdown of MAPK13 also blocked the effect of miR‑23a‑5p in osteogenic differentiation of hBMSCs, which was also confirmed by ALP and Alizarin Red S staining. These results indicated that by targeting MAPK13, miR‑23a‑5p serves a vital role in osteogenic differentiation of hBMSCs, which may provide novel clinical treatments for bone injury however, further studies are required.