Dioscin improves postmenopausal osteoporosis through inducing bone formation and inhibiting apoptosis in ovariectomized rats

Postmenopausal osteoporosis (PMO) has become a public health problem worldwide. Hormonal replacement therapy (HRT) is the most popular treatment for PMO at present, but the side effects, including increased risk of endometrial cancer and breast cancer, limit its clinical use. Therefore, finding a new medication with high efficiency and less side-effects is urgently required. Dioscin is the main ingredient of some medicinal plants such as Dioscorea nipponica Makino and Dioscorea zingiberensis Wrigh. It is reported that dioscin has anti-tumoral and anti-atherosclerotic activity as well as an inhibitory effect on hepatic fibrosis. In this study, the effects of dioscin on PMO were examined and the mechanisms were analyzed. The results indicated that the bone mineral density and ultimate load of PMO rats were increased after being treated with dioscin. H&E staining and immunohistochemical staining showed the bone trabeculae formation and bone differentiation of PMO rats were promoted by dioscin. Western blots revealed that dioscin could activate the PI3K/P38/AKT signaling pathway and inhibit the apoptosis signaling pathway in bone tissue cells of PMO rats. In addition, MTT assays showed that MC3T3-E1 cell viability could be improved by dioscin. These results suggest dioscin is a potential therapeutic reagent for osteoporosis and deserves further investigation.