毛蕊花糖苷与^99Tc-MDP联合治疗糖皮质激素诱导大鼠骨质疏松的效果及其分子机制研究

目的探索毛蕊花糖苷(verbascoside,Ver)联合^99 Tc-亚甲基双膦酸盐(^99-Technetium-methylene diphosphonate,^99 Tc-MDP)对糖皮质激素诱导大鼠骨质疏松(glucocorticoid-induced osteoporosis,GIO)的治疗作用,及其分子机制。方法SD大鼠连续8周肌肉注射地塞米松(dexamethasone,Dex)磷酸钠(1 mg/kg,1周2次)建立GIO模型。Dex造模同时,Ver组、联合组、^99 Tc-MDP组、模型组大鼠分别给与Ver(30 mg/kg)、联合^99 Tc-MDP(5 mg/kg)、Ver联合^99 Tc-MDP(5 mg/kg)、生理盐水,对照组大鼠不予造模。给药8周后检测相关指标。结果与对照组比较,模型组的大鼠的体重、股骨干重明显降低,骨代谢相关血液指标明显异常;双能X线吸收法(dual-energy X-ray absorption,DXA)结果显示:模型组的大鼠全身、腰椎体及股骨骨密度均明显降低;股骨三点弯曲实验最大载荷、弹性载荷、弹性位移及弹性模量等参数也都明显降低;进一步RT-PCR结果显示,模型组骨组织中USP10及FLT3表达明显高于对照组。而毛蕊花糖苷及联合^99 Tc-MDP治疗均明显改善上述症状。进一步研究发现毛蕊花糖苷组和联合用药组的USP10/FLT3表达明显低于^99 Tc-MDP组及模型组,而^99 Tc-MDP组与模型组之间的表达差异无统计学意义。结论毛蕊花糖苷可以抑制大鼠骨组织USP10/FLT3通路的活性,进而改善GIO;毛蕊花糖苷和^99 Tc-MDP治疗GIO大鼠具有良好的药理协同作用,并且是通过作用不同的分子靶点而完成的。

Therapeutic effect and molecular mechanism of verbascoside combined with 99Tc-MDP on glucocorticoid-induced osteoporosis in rats

Objective To explore the therapeutic effect of verbascoside (Ver) combined with 99Tc-methylenediphosphate (99Tc-MDP) on glucocorticoid-induced osteoporosis (GIO) in rats and its molecular mechanism. Methods SD rats received muscular injection of dexamethasone (Dex) sodium phosphate (1mg/kg, twice a week) for 8 weeks to establish GIO model. After GIO model was established, rats in Ver group, combined group, 99Tc-MDP group, and model group received Ver (30mg/kg), Ver combined 99Tc-MDP (5mg/kg) 99Tc-MDP (5mg/kg), or normal saline, respectively. Rats in the control group were not modeled. The related indexes were detected after 8 weeks of the drug administration. Results Compared with those in rats of the control group, the body weight and weight of the femoral shaft in rats of the model group reduced significantly, and the blood indexes related to bone metabolism were obviously abnormal. The results of dual-energy X-ray absorption (DXA) showed that bone mineral density of the whole body, the lumbar spine, and the femur in the model group decreased significantly. The maximum load, elastic load, elastic displacement, and elastic modulus of the three-point bending test of the femur also reduced significantly. RT-PCR results showed that the expressions of USP10 and FLT3 in the bone tissue of the model group were higher than those in the control group. The above symptoms were relieved after the treatment with Ver and 99Tc-MDP. Further study showed that USP10/FLT3 expression in the Ver group and the combination group was significantly lower than that in the 99Tc-MDP group and the model group, but there was no significant difference between the 99Tc-MDP group and the model group. Conclusion Ver inhibits the activity of USP10/FLT3 pathway in rat bone tissue and relieves GIO. Ver and 99Tc-MDP have a good pharmacological synergistic effect on the treatment GIO rats. This is accomplished by acting on different molecular targets.