补肾通络方对去卵巢大鼠破骨细胞组织蛋白酶K表达的影响

Effect of Bushen Tongluo Prescription on Osteoclast Cathepsin K in Ovariectomized Rats

【目的】探讨组织蛋白酶K(cathepsin K,CK)在骨质疏松症发病中的意义,观察补肾通络方对去卵巢大鼠破骨细胞CK表达的影响。【方法】选用30只雌性SD大鼠随机分成3组:假手术组、模型组及补肾通络方组(中药组,剂量为12.46 g.kg-1.d-1);后2组切除双侧卵巢,4周后中药组给予补肾通络方灌胃。分别于第6、12周测定各组大鼠全身骨密度(BMD),并采用Western blot及逆转录—聚合酶链反应(RT-PCR)法测定体外分离培养破骨细胞中CK的蛋白及基因表达。【结果】体外分离培养椎骨来源的破骨细胞具有成熟破骨细胞的表型特征,去卵巢模型大鼠骨密度在时效上与CK的表达呈现负相关;补肾通络方以时效方式下调CK蛋白及CK mRNA的表达水平(均P<0.05)。【结论】CK的过度表达是导致骨密度下降的重要原因,是骨质疏松症发生的潜在危险因子;以时效方式下调CK蛋白及CK mRNA的表达进而治疗骨质疏松症可能是补肾通络方的作用机制之一。

Objective To approach the effect of cathepsin K（CK） on the onset of osteoporosis,and to study the influence of Bushen Tongluo Prescription（BTP,with the actions of invigorating the kidney and dredging the meridians） on osteoclast CK in ovariectomized rats.Methods Thirty female SD rats were divided into three groups randomly： sham-operation group,model group and BTP（12.46g.kg-1.d-1） group.The bilateral ovaries in rats of the model group and BTP group were removed.Four weeks later,BTP group were given gastric gavage of BTP.On the 6th and 12th weeks,we detected the general bone density of rats,examined CK expressionin osteoclasts with Western blot and reverse transcription-polymerase chain reaction（RT-PCR） methods.ResultsThe in-vitro cultured cells had the phenotype feature of mature osteoclasts.The bone mineral density of ovariectomized rats was negatively correlated with CK expression in time-effect manner.BTP down-regulated the CK protein and CK mRNA expression（P〈0.05） in time-effect manner.Conclusion CK overexpression contributes to the decrease of bone mineral density,which is one of the potential risk factors of osteoporosis.Down-regulation of CK protein and CK mRNA expression in time-effect manner is probably one of the therapeutic mechanisms of BTP for osteoporosis.