Buqi-Tongluo Decoction inhibits osteoclastogenesis and alleviates bone loss in ovariectomized rats by attenuating NFATc1, MAPK, NF-κB signaling

Osteoporosis (OP) is the most common skeletal condition that is characterized by decreased bone mass and bone strength and increased fragility. Buqi-Tongluo (BQTL) decoction is a traditional Chinese medicine (TCM) prescription and its role in treating bone diseases such as OP has yet to be determined. We utilized MTS assay to determine whether BQTL, at certain concentrations, has any proliferative or toxic effects on Bone Marrow Macrophages (BMMs), and combined it with TRAcP experiments to investigate the impact of BQTL on OC differentiation. RT-PCR and Western blot were employed to assess the relative expression levels of osteoclast-specific genes and proteins under BQTL stimulation.In this study, BQTL was found to suppress RANKL-induced osteoclastogenesis and OC resorption activity in vitro dose-dependently without any observable cytotoxicity. The inhibitory effects of BQTL on OC formation and function were mainly through attenuating the MAPK, NF-κB, and Calcineurin signaling pathways. BQTL’s inhibitory capability was also examined in vivo using an ovariectomized rat model, in which our results demonstrated that BQTL had strong protective effect against bone loss.BQTL may be an effective therapeutic TCM to treat postmenopausal OP and alleviate bone loss-induced estrogen deficiency and related diseases