唑来膦酸对破骨细胞分化中钙调蛋白、钙调磷酸酶表达的影响

The effect of zoledronate on gene expression of calmodulin and calcineurin during osteoclast differentiation

目的 :探讨唑来膦酸(zoledronate,ZOL)对破骨细胞分化中钙调蛋白(calmodulin)和钙调磷酸酶(calcineurin)基因表达的影响。方法:小鼠RAW264.7细胞分为A、B两组,均用100 ng/m L核因子κB受体激活蛋白配体(RANKL)诱导4 d;B组细胞在RANKL诱导第2天加入1×10-6mol/L ZOL处理48 h。RANKL诱导4 d后收获细胞,检测破骨细胞生成及calmodulin、calcineurin基因表达情况。结果 :B组多核破骨细胞数、吸收陷窝数目及面积分别为(8.8±2.3)个、(6.7±1.2)个和(997.1±14.8)μm^2,均显著低于A组的(19.7±2.9)个、(13.3±1.5)个和(1 676.9±24.9)μm^2(P<0.01)。B组calmodulin mRNA及蛋白水平较A组分别降低了51.0%和78.7%(P<0.05),calcineurin则分别下降了37.0%和69.5%(P<0.01)。免疫荧光细胞化学显示,B组calmodulin、calcineurin的荧光强度较A组也明显下降。结论:ZOL可显著抑制破骨细胞生成,并下调破骨细胞分化中calmodulin和calcineurin的m RNA和蛋白水平,而calmodulin、calcineurin可能参与了ZOL对破骨细胞形成和功能的抑制。

Objective：The study is aimed to examine the effects of zoledronate（ZOL） on gene expression of calmodulin and calcineurin during differentiation of osteoclasts. Methods：RAW264.7 cells were divided into 2 groups,group A and group B. The cells in both groups were induced with 100 ng / ml RANKL（ligand of receptor activator of nuclear factor κB）for 4 d for osteoclast differentiation. At the second day of RANKL induction,cells in group B also treated with 1×10^（-6）mol / L ZOL for 48 h. Four days later,the cells were harvested and examined for osteoclastogenesis,as well as gene expression of both calmodulin and calcineurin. Results： TRAP positive multinuclear cells,number and size of resorption lacunaes in group B were 8.8 ± 2.3,6.7 ± 1.2 and 997.1 ± 14.8 μm^2 respevtively,which were significantly lower than those（19.7 ± 2.9,13.3 ± 1.5 and 1676.9 ± 24.9 μm^2）in group A（P〈0.01）. mRNA and protein level of calmodulin in group B decreased about 51% and 78.7%,respectively when compared with group A（P〈0.05）,and those of calcineurin also decreased about 37% and 69.5%,respectively（P〈0.05）. Immunofluorescent cytochemistry showed obvious decrease of fluorescent intensity of calmodulin and calcineurin protein in group B when compared with group A. Conclusion：ZOL significantly inhibits osteoclastogenesis and down-regulates gene expression of calmodulin and calcineurin,which may play a role in ZOL-induced inhibition of osteoclastogenesis.