Chinese Herbal Tanshinol Prevents Osteoporosis via Coordinately Promoting Osteogenesis and Inhibiting Osteoclastogenesis

Abstract Background: Osteoporosis severely affects patients’ life quality due to increased risks of fragility fractures. Tanshinol is a primary water-soluble compound purified from the Chinese herb Salvia Miltiorrhiza, which exhibits potent antioxidant and anti-inflammatory properties. However, whether Tanshinol functions in preventing and protecting osteoporosis remains unknown. Thus, current study proposed to systematically investigate the protective effects and the underlying mechanisms of Tanshinol in bone marrow mesenchymal stem cells (BM-MSCs) and ovariectomized (OVX) mice model. Materials and methods: Different concentrations of Tanshinol were given to induce differentiation of BM-MSCs respectively, and detected the expression of key markers of osteoclast and osteogenesis. The C57BL/6 mice were divided into control group, model group, low (80 mg/kg×day, i.g), medium (160 mg/kg×day, i.g) and high (240 mg/kg×day, i.g) concentrations Tanshinol groups. After 6 weeks treatment of Tanshinol, mice distal femurs were taken to measure bone mineral density (BMD) and three dimension parameters.Results: In the present study, we for the first time showed that Tanshinol could promote osteogenesis in the mouse BM-MSCs, as seen from the increase of the osteogenic markers such as ALP activity and collagen I. Meanwhile, Tanshinol inhibited the RANKL induced osteoclastogenesis in the bone marrow monocytes (BMMs). Animal studies showed that oral delivery of Tanshinol could attenuate in ovariectomy induced osteoporosis. Molecularly, Tanshinol activated Wnt signal pathway in MSCs while inhibited Akt in BMMs, suggesting these pathways might be involved in the osteoporosis protective role of Tanshinol. Conclusions: our study has revealed a potential application of Salvia miltiorrhiza derivative Tanshinol in the treatment of osteoporosis.