Angelica sinensis extract inhibits RANKL-mediated osteoclastogenesis by down-regulated the expression of NFATc1 in mouse bone marrow cells

Background: Destructive erosion of bone or osteolysis is a major complication of inflammatory conditions such as rheumatoid arthritis (RA), periodontal disease, and periprosthetic osteolysis. Natural plant-derived products have received recent attention as potential therapeutic and preventative drugs in human disease. Methods: The effect of Angelica sinensis (AS) extract on RANKL-induced osteoclast differentiation was examined in this study. The osteoclast precursor cell line bone marrow macrophages (BMMs) was cultured and stimulated with RANKL followed by treatment with AS at several doses. Gene expression profiles of c-Fos, c-Jun, NFATc1, TRAP, and OSCAR were sequentially evaluated. Results: AS extract inhibited RANKL-mediated osteoclast differentiation in BMMs in a dose-dependent manner without any evidence of cytotoxicity. AS extract strongly inhibited p38, ERK, JNK, p65 phosphorylation and I-kappa B degradation in RANKL-stimulated BMMs. AS extract also inhibited the mRNA expression of c-Fos, c-Jun, NFATc1, TRAP, and OSCAR in RANKL-treated BMMs. Moreover, RANKL-induced c-Fos, c-Jun and NFATc1 protein expression was suppressed by AS extract. Conclusions: These results collectively suggested that AS extract demonstrated inhibitory effects on RANKL-mediated osteoclast differentiation in bone marrow macrophages in vitro, indicating that AS may therefore serve as a useful drug in the prevention of bone loss.