背景:复方生脉成骨胶囊治疗早期激素性股骨头坏死的疗效佳,但具体治疗机制尚不完全明确. 目的:观察复方生脉成骨胶囊干预对激素性股骨头坏死大鼠骨组织中岩藻糖基转移酶8、成骨基因及Wnt/β-catenin信号通路蛋白表达的影响. 方法:取60只雄性SD大鼠,采用随机数字表法分为空白组、模型组、中药低剂量组、中药中剂量组及中药高剂量组,每组12只.模型组和中药低、中、高剂量组通过皮下注射咪喹莫特(每2周一次,共2次)与臀肌注射甲强龙(1次/周,共4次)的方法建立激素性股骨头坏死模型,末次造模给药后第2天,中药低、中、高剂量组分别灌胃给予1.89,3.78,7.56 g/(kg·d)的复方生脉成骨胶囊溶液,模型组灌胃给予等量生理盐水,连续给药8周.给药结束后,分别进行股骨头micro-CT扫描、组织学染色、压缩实验、RT-qPCR及Western blot检测. 结果与结论:①micro-CT扫描显示,与空白组比较,模型组大鼠骨小梁体积分数、骨小梁数量及骨小梁厚度减少(P<0.05),骨小梁离散度增加(P<0.05);与模型组比较,中药低、中、高剂量组骨小梁体积分数、骨小梁数量及骨小梁厚度增加(P<0.05),骨小梁离散度减少(P<0.05),且呈剂量依赖性.②苏木精-伊红染色显示,与模型组比较,中药低、中、高剂量组空骨陷窝率减少(P<0.05),且呈剂量依赖性;免疫组化染色显示,与空白组比较,模型组岩藻糖基转移酶8、Runx2、骨形态发生蛋白2的蛋白表达降低(P<0.05);与模型组比较,中药低、中、高剂量组岩藻糖基转移酶8、Runx2、骨形态发生蛋白2的蛋白表达升高(P<0.05),且呈剂量依赖性.③压缩实验显示,与模型组相比,中药低、中、高剂量组股骨头最大载荷及弹性模量升高(P<0.05),且呈剂量依赖性;④RT-qPCR及Western blot检测显示,与空白组相比,模型组岩藻糖基转移酶8、Runx2、碱性磷酸酶、骨钙素、成骨细胞特异性转录因子及骨形态发生蛋白2的mRNA与蛋白表达降低(P<0.05);与模型组相比,中药低、中、高剂量组上述指标的mRNA与蛋白表达升高(P<0.05),且呈剂量依赖性.与空白组比较,模型组Wnt2、低密度脂蛋白受体相关蛋白5及β-连环蛋白的mRNA与蛋白表达降低(P<0.05),糖原合成酶激酶3β的mRNA与蛋白表达升高(P<0.05);与模型组比较,中药低、中、高剂量组Wnt2、低密度脂蛋白受体相关蛋白5及β-连环蛋白的mRNA与蛋白表达升高(P<0.05),糖原合成酶激酶3β的mRNA与蛋白表达降低(P<0.05),且呈剂量依赖性.⑤结果表明,复方生脉成骨胶囊治疗激素性股骨头坏死的机制可能是通过上调岩藻糖基转移酶8表达来激活Wnt/β-catenin信号通路,促进骨形成.
BACKGROUND:Compound Shengmai Chenggu capsule has good therapeutic effects on early steroid-induced osteonecrosis of the femoral head,but the exact mechanism of treatment is not fully understood. OBJECTIVE:To observe the effect of compound Shengmai Chenggu capsule on fucosyltransferase 8,osteogenic gene and Wnt/β-catenin in bone tissue of rats with steroid-induced osteonecrosis of the femoral head. METHODS:Sixty Sprague-Dawley rats were randomized into blank group,model group,low-,middle-,and high-dose drug groups(n=12 per group).In the latter four groups,animal models of steroid-induced osteonecrosis of the femoral head were established by subcutaneous injection of imiquimod(once every 2 weeks,2 times in total)and gluteal muscle injection of methylprednisolone(once a week,4 times in total).The low-,middle-and high-dose drug groups were given 1.89,3.78 and 7.56 g/kg per day compound Shengmai Chenggu capsule solution by gavage respectively on the second day after the last modeling.The same amount of saline was given by gavage to the model group.Administration lasted 8 weeks.After the administration,micro-CT scan,histological staining,compression test,RT-qPCR and western blot were performed on the femoral head. RESULTS AND CONCLUSION:Micro-CT scan results showed that compared with the blank group,trabecular volume fraction,trabecular number and trabecular thickness were significantly decreased(P<0.05),while trabecular separation was increased in the model group(P<0.05).Compared with the model group,the compound Shengmai Chenggu capsule could increase trabecular volume fraction,trabecular number and trabecular thickness(P<0.05),and decrease trabecular separation(P<0.05)in a dose-dependent manner.Hematoxylin-eosin staining results showed that compared with the model group,the rate of empty bone lacunae was reduced in a dose-dependent group in the low-,middle-,and high-dose compound Shengmai Chenggu capsule groups(P<0.05).Immunohistochemical staining results showed that compared with the blank group,the protein expression of fucosyltransferase 8,Runx2 and bone morphogenetic protein 2 was reduced in the model group(P<0.05);compared with the model group,the compound Shengmai Chenggu capsule increased the protein expression of fucosyltransferase 8,Runx2 and bone morphogenetic protein 2 in a dose-dependent manner(P<0.05).Results from the compression test showed that there was a dose-dependent increase in the maximum load and elastic modulus of the femoral head in the low-,middle-,and high-dose compound Shengmai Chenggu capsule groups compared with the model group(P<0.05).RT-qPCR and western blot results showed that the mRNA and protein expressions of fucosyltransferase 8,Runx2,alkaline phosphatase,osteocalcin,osteoblast-specific transcription factor and bone morphogenetic protein 2 were decreased in the model group compared with the blank group(P<0.05);compared with the model group,there was a dose-dependent increase in the mRNA and protein expressions of the above indicators in the low-,middle-,and high-dose compound Shengmai Chenggu capsule groups compared with the model group(P<0.05).Compared with the blank group,the mRNA and protein expression of Wnt2,low-density lipoprotein receptor-related protein 5 and β-catenin were decreased(P<0.05)and the mRNA and protein expressions of glycogen synthase kinase 3β were increased(P<0.05)in the model group;compared with the model group,there was a dose-dependent increase in the mRNA and protein expressions of Wnt2,low-density lipoprotein receptor-related protein 5 and β-catenin(P<0.05)but a dose-dependent decrease in the mRNA and protein expressions of lycogen synthase kinase 3β(P<0.05)in the low-,middle-,and high-dose compound Shengmai Chenggu capsule groups.To conclude,the mechanism by which the compound Shengmai Chenggu capsule treats steroid-induced osteonecrosis of the femoral head may activate the Wnt/β-catenin signaling pathway through the up-regulation of fucosyltransferase 8,thereby promoting bone formation.