病证结合骨质疏松模型大鼠骨骼的生物力学性能分析

Biomechanical analysis of the bones in a rat model of osteoporosis based on the combination of disease and syndrome

背景:肾虚是骨质疏松症的最主要病机,对肾阳虚、肾阴虚与骨质疏松的关系研究有利于病证结合临床诊疗模式的发展。目的:评价右归丸对肾阳虚、肾阴虚大鼠股骨生物力学性能的影响差异,从生物力学角度论证骨质疏松症病证结合、因证施药的科学性。方法:手术摘除60只雌性SD大鼠双侧卵巢建立骨质疏松模型,10周后将大鼠随机分为肾阴虚组(n=30)和肾阳虚组(n=30),肾阳虚组臀部肌肉注射氢化可的松注射液,肾阴虚组灌胃甲状腺片混悬药液,1次/d,连续14 d。造模结束后,每组取20只灌胃右归丸混悬液,1次/d,连续12周,剩余10只作为对照不灌胃。灌胃结束后使用Micro-CT扫描测量股骨微结构参数,在力学试验机上对股骨分别进行三点弯曲、有限元仿真、股骨头压缩及表面压痕分布实验。结果与结论:①Micro-CT扫描显示,与肾阴虚组比较,肾阴虚+右归丸组股骨骨密度、骨体积分数、骨表面密度、骨小梁数量、骨小梁分离度升高(P<0.05);与肾阳虚组比较,肾阳虚+右归丸组股骨骨体积分数、骨表面密度、骨小梁数量及骨小梁厚度升高(P<0.05);②三点弯曲实验显示,与肾阳虚组相比,肾阳虚+右归丸组股骨弹性模量、最大抗弯强度和弯曲断裂强度均降低(P<0.05),韧性提高(P<0.05);③有限元仿真显示,右归丸能显著提高肾阳虚组大鼠股骨抗骨折能力,对肾阴虚组大鼠不产生明显作用;股骨头压缩实验显示,右归丸可增强肾阳虚组大鼠股骨头抵抗形变的能力,但右归丸对肾阴虚组和肾阳虚组大鼠股骨头表面性能的影响无显著区别;④结果表明,右归丸可增强肾阳虚骨质疏松骨骼生物力学性能,但对肾阴虚骨质疏松骨骼无显著影响。

BACKGROUND:Kidney deficiency is the main pathogenesis of osteoporosis.To study the relationship between the two major syndrome types of kidney deficiency,Kidney-Yang deficiency and Kidney-Yin deficiency,is beneficial for the development of clinical diagnosis and treatments based on the combination of disease and syndrome.OBJECTIVE:To evaluate the biomechanical differences of the rat femurs with Kidney-Yang deficiency and Kidney-Yin deficiency caused by Yougui pills,and to demonstrate the scientific efficacy of medication based on the combination of disease and syndrome in osteoporosis from a biomechanical perspective.METHODS:The bilateral ovaries of 60 female Sprague-Dawley rats were surgically removed to establish an ovariectomized osteoporosis model.At 10 weeks after modeling,all the rats were randomly divided into a Kidney-Yang deficiency group(n=30)and a Kidney-Yin deficiency group(n=30).Rats with Kidney-Yang deficiency were given gluteal intramuscular injection of hydrocortisone,while rats with Kidney-Yin deficiency were orally administered with thyroid tablet suspension,once a day,for 14 consecutive days.After successful modeling,20 rats in each group were given a suspension of Yougui pills by gavage once a day for 12 consecutive weeks and the remaining 10 rats were used as the control group without intervention.After gavage,the microstructural parameters of the bone were measured using Micro-CT scanning.Three-point bending,finite element simulation,femoral head compression,and surface indentation distribution experiments of the femurs were performed on a mechanical testing machine.RESULTS AND CONCLUSION:Micro-CT revealed that the femoral bone density,bone volume fraction,bone surface density,trabecular number,and trabecular separation were improved in the Kidney-Yin deficiency+Yougui pills group compared with the Kidney-Yin deficiency group(P<0.05);the femoral bone volume fraction,bone surface density,trabecular number,and trabecular thickness were improved in the Kidney-Yang deficiency+Yougui pills group compared with the Kidney-Yang deficiency group(P<0.05).The three-point bending experiment showed that the femur elastic modulus,maximum bending strength and bending fracture strength were decreased(P<0.05)and toughness was increased(P<0.05)in the Kidney-Yang deficiency+Yougui pills group compared with the Kidney-Yang deficiency group.Finite element simulation showed that Yougui pills could significantly improve the bending resistance of the femurs in the Kidney-Yang deficiency group,but had no significant effect on the Kidney-Yin deficiency group.The femoral head compression experiments showed that Yougui pills could enhance the ability of the femoral head to resist deformation in the Kidney-Yang deficiency group,but there was no significant difference in the effect of Yougui pills on the surface properties of the femoral head in the Kidney-Yin deficiency group and the Kidney-Yang deficiency group.To conclude,Yougui pills can significantly enhance the biomechanical properties of the osteoporotic bones with Kidney-Yang deficiency,but have no significant effect on the osteoporotic bone with Kidney-Yin deficiency.