RÉSUMÉ
Objective:To explore the effect of anemarrhena asphodeloside BⅡ (TBⅡ) on the expressions of nuclear transcription factor-κB receptor activator factor ligand （RANKL）, RANK and C-FOS genes during osteoclast differentiation. Method:Molecular docking software LeDock was used to score the docking of TBⅡ with RANKL, RANK and C-FOS. RAW264.7 was treated with soluble RANKL（sRANKL） and divided into control group, sRANKL group (model group), Icariin (Ica) group, low-dose TBIⅡ group (2 μmol·L-1), medium-dose TBⅡ group (4 μmol·L-1), and high-dose TBⅡ group (8 μmol·L-1). The corresponding kit was used to detect iconic enzyme (TRAP) of osteoclast differentiation. Total RNA was extracted by trizol method, Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) was used to detect the expressions of C-FOS, upstream RANKL/RANK and downstream nuclear factor of activated T-cells cytoplasmic 1 (NFATC1), and osteoprotegerin OPG. Result:The molecular docking score were -11.86, -11.38, -12.34 kcal·mol-1, and there might be multiple binding sites between TBII as well as RANKL, RANK and C-FOS. Compared with the control group, the content of TRAP in model group increased significantly (P<0.01), and compared with model group, the content of TRAP in each administration group decreased significantly (P<0.01), and TBⅡ decreased the content of TRAP in a dose-dependent manner. Compared with the control group, the expressions of RANKL, RANK, C-FOS and NFATC1 increased (P<0.01), whereas the expression of OPG decreased (P<0.01) in model group. Compared with model group, the expressions of RANKL, RANK, C-FOS and NFATC1 decreased (P<0.01), while the expression of OPG increased (P<0.01) in each administration group. Conclusion:TBⅡ may inhibit the differentiation of osteoclast precursors into osteoclasts, inhibit osteoclast activity, reduce bone resorption and improve osteoporosis by regulating RANKL/RANK/C-FOS signal pathway.