Polydatin alleviates osteoporosis by enhancing the osteogenic differentiation of osteoblasts.

OBJECTIVE: Osteoporosis is a severe degenerative chronic metabolic bone disease associated with high fracture risk. Polydatin (PD), a major bioactive component of Polygonum cuspidatum, has antioxidant and anti-inflammatory effects. This study investigated the anti-osteoporotic activity of PD in ovariectomized (OVX) mice and elucidated its underlying molecular mechanisms. SUBJECTS AND METHODS: An osteoporosis mouse model was established using OVX mice. OVX mice were then administered 10 or 40 mg/kg of PD for 60 days. Micro-CT and three-point bending tests were used to determine the therapeutic activities of PD in OVX mice. H&E staining was used to determine whether PD induced hepatorenal toxicity. In addition, the cellular and molecular mechanisms underlying the functionality of PD were elucidated. RESULTS: Micro-CT results showed that compared to control mice, the bone mass of OVX mice was significantly reduced due to estrogen deficiency; however, PD administration significantly elevated bone mass. Furthermore, PD substantially improved the trabecular microstructure parameters of the femur and enhanced bone strength compared with OVX mice. Hepatorenal toxicity was not observed in liver and kidney samples stained with H&E. PD significantly increased the proliferation of pre-osteoblast MC3T3-E1 cells and upregulated the expression of osteogenic differentiation markers compared to those in controls, as determined by qRT-PCR and western blotting. CONCLUSIONS: PD exerted a significant anti-osteoporotic effect in OVX mice by promoting osteogenesis. PD has great potential as a therapeutic option for osteoporosis.