Therapeutic effects of bone mesenchymal stem cells on oral and maxillofacial defects: a novel signaling pathway involving miR-31/CXCR4/Akt axis.

Context: Although bone mesenchymal stem cells (BMSCs) have been used for the treatment of oral and maxillofacial defects, the survival rate and limited proliferation reduces the therapeutic efficiency of BMSC. Objective: The aim of our study is to explore the role of miR-31 in regulating survival, proliferation, and migration of BMSC in vitro . Materials and methods: LPS was used in vitro to induce BMSC damage and then miR-31 was used to incubate with BMSC. Subsequently, BMSC proliferation, survival, and migration were determined via ELISA, qPCR, western blots, and immunofluorescence. Results: The expression of miR-31 was downregulated in response to LPS stress. Interestingly, supplementation of miR-31 could reverse the survival, proliferation and migration of BMSC under LPS. Mechanically, miR-31 treatment inhibited the activation of caspase, and thus promoted BMSC survival. Besides, miR-31 upregulated the genes related to cell proliferation, an effect that was followed by an increase in the levels of migratory factors. Further, we found that miR-31 treatment activated the CXCR4/Akt pathway and blockade of CXCR4/Akt could abolish the beneficial effects of miR-31 on BMSC proliferation, survival, and migration. Conclusions: miR-31 could increase the therapeutic efficiency of BMSC via the CXCR4/Akt pathway.