不同浓度骨碎补总黄酮对模型大鼠的组织蛋白酶K及骨矿含量的影响

The Influence of Different-concentration Drynaria Total Flavonoids on Cathepsin K and Bone Mineral Content in Ovariectomized Rats

目的:用不同浓度的骨碎补总黄酮对去卵巢雌性大鼠进行干预,观察其对大鼠右股骨骨矿含量(BMC)的影响以及对右胫骨干骺端中组织蛋白酶K(Cathepsin K)基因表达的影响,初步研究骨碎补总黄酮防治骨质疏松症的机制。方法:选取3月龄雌性SD大鼠72只,随机分为6组:低剂量组、中剂量组、高剂量组、雌激素组、假手术组、正常组。去卵巢造模成功后予灌胃,并于造模成功后即刻、3个月、6个月每组处死4只大鼠,取右股骨标本,用MEDILINK OSTEO-CORE-2给予测定BMC,取右胫骨近端干骺端标本,荧光定量PCR测定Cathepsin K mRNA表达量,用SPSS17.0软件进行数据分析。结果:治疗6月后各治疗组及雌激素组与造模成功时骨矿密度比较差异有统计学意义(P<0.05);治疗6月后各治疗组及雌激素组与正常组及假手术组比较差异无统计学意义(P>0.05);各治疗组与雌激素组右胫骨干骺端Ca-thepsin K mRNA表达量相比差异有统计学意义(P<0.05);各治疗组与假手术组及正常组右胫骨干骺端Cathepsin KmRNA表达量比较差异有统计学意义(P<0.01)。结论:骨碎补总黄酮能提高模型大鼠BMC,可能是通过降低骨组织中Cathepsin K mRNA表达量的方式作为其防治骨质疏松症的机制。

To observe gene expression of cathepsin K in right tibial metaphysic and bone mineral content （BMC） in right thighbone of ovariectomized rats treated with different-concentration drynaria total flavonoids, and to investigate the mechanism of drynaria total flavonoids in preventing osteoporosis. Methods.. Seventy-two three-month old female SD rats were randomly divide into 6 groups, low-dose total flavonoids group, middle-dose total flavonoids group, high-dose to- tal flavonoids group, estrogen group, sham operation group, and normal group. After the model was successfully estab lished, intragastric administration of total flavonoids was performed. Immediately after modeling, 3, and 6 months after modeling, 4 rats of each group were sacrificed for determination of right thighbone BMC by MEDILINK OSTEOCORE-2. Meanwhile, cathepsin K mRNA expression levels in right tibial metaphysic bone tissue was assayed by fluorescence quanti- tative PCR. SPSS17.0 software was applied for statistical analysis. Results.. After 6 months treatment, right thighbone BMC in the treatment groups and estrogen group was obviously increased compared with before treatment （P〈0. 05）. There was no significant difference in BMC between treatment groups, estrogen group and normal group and sham opera tion group （P〈0.05）. （he gene expression of cathepsin K mRNA in right tibial metaphysic bone tissue was significantly declined between the treatment groups and the estrogen group （P〈0.05）. Remarkable difference was found in cathepsin K mRNA expression between treatment groups and sham operation group and normal group （P〈0.01）. Conclusion：Drynaria total flavonoids can improve BMC by inhibiting Cathepsin K mRNA gene expression in bone tissue. This may be a way for the treatment of osteoporosis.