双膦酸盐对破骨细胞分化中组织蛋白酶K及骨吸收功能的影响

背景：有研究表明双膦酸盐可抑制破骨细胞的骨吸收功能，但对其骨吸收功能关键细胞因子组织蛋白酶K是否产生作用，至今少有报道。目的：观察双膦酸盐对破骨细胞分化中组织蛋白酶K及骨吸收功能影响。方法：用小鼠单核巨噬细胞RAW264.7诱导培养破骨细胞。实验分2组：对照组加入质量浓度100μg/L核因子κB受体活化因子配体进行诱导至收获细胞，双膦酸盐组在对照组的基础上加入10-7 mol/L阿仑膦酸盐处理至收获细胞。培养第7天检测各组破骨细胞生成和骨吸收功能，培养72 h免疫荧光检测两组组织蛋白酶K表达差异，Western blot检测组织蛋白酶K蛋白表达情况。结果与结论：两组均有抗酒石酸酸性磷酸酶阳性多核破骨细胞生成，并在牙本质磨片上形成吸收陷窝；但对照组抗酒石酸酸性磷酸酶阳性多核细胞数目、吸收陷窝数目及陷窝面积均大于双膦酸盐组（P〈0.01）。免疫荧光检测组织蛋白酶K表达对照组强于双膦酸盐组（P〈0.01）；Western blot检测组织蛋白酶K表达双膦酸盐组低于对照组（P〈0.01）。结果证实，双膦酸盐通过抑制组织蛋白酶K因子的表达，阻碍破骨细胞的骨吸收功能。

Bisphosphonate effects on capthesin K and bone resorption function during osteoclast differentiation

BACKGROUND：Studies have shown that bisphosphonates inhibit osteoclast resorption, but whether cathepsin K, a key cytokine of bone resorption, plays an effect has rarely been reported. OBJECTIVE：To study the effect of bisphosphonate on capthesin K and bone resorption function during osteoclast differentiation. METHODS：Osteoclasts were cultured by mouse monocyte-macrophage cellline-RAW264.7. The cells were divided into two groups：control group, treated with 100μg/L receptor activator of nuclear factorκB ligand factor;alendronate group, treated with 100μg/L receptor activator of nuclear factorκB ligand factor＋10-7 mol/L alendronate. Osteoclastogenesis and resorption function of osteoclasts were examined at 7 days of culture and gene expression of capthesin K was detected by immunofluorescence method at 72 hours of culture. Western blot assay was used to detect capthesin K protein expression at 72 hours of culture. RESULTS AND CONCLUSION：Tartrate-resistant acid phosphatase positive multinuclear cells were observed and resorption lacunae formed in two groups. Control group showed the higher number of tartrate-resistant acid phosphatase positive multinuclear cells and larger size of resorption lacunae than the alendronate group （P〈0.01）. Immunofluorescence showed expression of capthesin K was higher in the control group than the alendronate group （P〈0.01）;furthermore, the protein expression of capthesin K was also lower in the alendronate group than the control group （P〈0.01）. These findings indicate that bisphosphonates could strongly inhibit osteoclastogenesis and its resorption function by inhibiting gene expression of capthesin K.