β-ecdysone promotes osteogenic differentiation of bone marrow mesenchymal stem cells

Background beta-ecdysone (beta Ecd) has numerous pharmacological effects, although its role in the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) has not yet been explored. Methods In cell experiments, BMSCs were induced to differentiate by osteogenic induction medium (OIM) or beta Ecd. In animal experiments, an osteonecrosis of the femoral head (ONFH) rat model was established using lipopolysaccharide plus methylprednisolone and treating the rats with beta Ecd. The osteogenic differentiation capacity of human BMSCs (hBMSCs) was analyzed by alkaline phosphatase and alizarin red S staining. Histopathological changes in rat femoral head tissues were observed by hematoxylin and eosin staining. The expression levels of RUNX2, COL1A1, OCN and phosphorylated Akt in BMSCs from rat femoral head tissues were measured by a quantitative real-time polymerase chain reaction or western blot analysis. Results Alkaline phosphatase activity and calcium nodules in the beta Ecd-treated BMSC group dose-dependently increased compared to those in the control and OIM groups. The hematoxylin and eosin staining results indicated that femoral head tissues of ONFH rats showed typical osteonecrosis, which could be ameliorated by beta Ecd. Western blot, quantitative real-time polymerase chain reaction and immunohistochemistry assays demonstrated that the expression levels of RUNX2, COL1A1 and OCN in hBMSCs and femoral head tissue models were obviously increased after beta Ecd treatment, and phosphoinositide 3-kinase and Akt phosphorylation were also increased. Conclusions beta Ecd may be beneficial for the recovery of ONFH patients by accelerating osteogenic differentiation of BMSCs, which may be a novel therapy for related diseases.