MicroRNAs-26 and related osteogenic target genes could play pivotal roles in Photobiomodulation and adipose-derived stem cells-based healing of critical size foot defects in the rat model

Abstract

Background Photobiomodulation therapy (PBMT) and human adipose-derived stem cells (hADSs) treatment are relatively invasive methods for treating bone defects. Specific and oriented cellular and molecular functions can be induced by applying an appropriate type of PBMT and ADSs. In this study, we aimed to explore the role of MicroRNAs pathways in the PBMT, hADS, and PBM+hADS based on promoting critical size fracture healing.MethodsA critical size femoral defect (CSFD) is induced in the right and left femoral bones of 24 rats. Then a human demineralized bone matrix scaffold (hDBMS) was engrafted into the CSFDs of all rats. Experiments are performed on 4 groups (12 rats per group): (1) Control (hDBMS); (2) hDBMS+hADS, hADS was engrafted into CSFDs; (3) hDBMS+PBM, the CSFD was exposed to PBM(810 nm wavelength, 1.2 J/cm2 energy density); (4) hDBMS+(hADS+PBM), hADSs were implanted into CSFD then were exposed to PBM. At 42 days after CSFD induction, the rats were killed and, the left and right CSFDs were removed for the mechanical compression tests, and molecular and cellular studies, respectively.ResultsThe results indicate that miRNA-26a, BMP, SMAD, RUNX, and OSTREX were more expressed in the treated groups than in the control group. Furthermore, the biomechanical and histological properties of CSFDs in treated groups were better than the control group. The correlation tests revealed a positive relationship between microRNA and improving biomechanical and cellular parameters of CSFDs in the rat model.ConclusionWe concluded that the MicroRNA-26 signaling pathway plays a significant role in the hADS, PBM, and hADS+PBM-based healing of CSFDs in rats.