Effect of low-level laser therapy and oxytocin on osteoporotic bone marrow-derived mesenchymal stem cells

Postmenopausal osteoporosis (OP) is a major concern for public health. Low-level laser therapy (LLLT) has a positive effect on the health of bone marrow mesenchymal stem cells (BMMSCs). The purpose of this study is to evaluate the influence of LLLT and oxytocin (OT) incubation-individually and in combination-on osteoporotic BMMSCs in ovariectomized rats. Twelve female rats were randomized into two groups to undergo either a sham surgery (sham group) or ovariectomy-induced osteoporosis (OVX group). MSCs harvested from the BM of healthy and OVX rats underwent culture expansion. There were five groups. In Groups one (sham-BMMSC) and two (OVX-BMMSC) the cells were held in osteogenic condition medium without any intervention. In the group three (OT), OT incubation with optimum dose was performed for 48 h (two times, 10^-12 molar). In Group four, laser-treated-OVX-BMMSCs were treated with optimum protocol of LLLT (one time, 1.2 J/cm² ). In Group five (laser + OT group), the OT incubation plus the laser irradiation was performed. The biostimulatory effect of LLLT is demonstrated by a significant increase in the viability of OVX-BMMSCs, cell cycle, and extracellular levels of Transforming growth factor beta (TGF-β), insulin-like growth factor-I (IGF-I), and Alkaline phosphatase (ALP) compared to control OVX-BMMSCs and/or the sham group. OT incubation and laser + OT incubation have a positive effect on OVX-BMMSCs. However, LLLT is more effective statistically. We conclude that LLLT significantly improved cell viability, enhanced the osteogenic potential of the OVX-BMMSCs, and increased the extracellular levels of the TGF-β, IGF-I, and ALP.