淫羊藿定对骨质疏松大鼠的治疗作用及机制研究

Effect of epimedium on osteoporosis in rats and its mechanism

目的观察淫羊藿定对去双侧卵巢导致骨质疏松症大鼠的治疗作用,并探讨其可能的作用机制。方法雌性SD大鼠48只,手术切除双侧卵巢,术后恢复4周,复制骨质疏松大鼠模型。随机分为4组,即淫羊藿定高剂量组(800 mg/kg)、低剂量组(200 mg/kg),骨化三醇组(1μg/kg)和模型组(等量蒸馏水)。另取12只大鼠,开腹腔剥离卵巢但不切除作为假手术组(等量蒸馏水)。各组大鼠连续给药12周后处死,取大鼠股骨,骨密度仪测定干骺端骨密度;切片观察骨组织形态改变;荧光定量PCR检测骨组织中OPG、RANK、RANKL mRNA表达。结果淫羊藿定显著提高了骨质疏松大鼠股骨上干骺端骨密度,使骨小梁密集,排列较整齐,且提高了成骨细胞数量。同时,还明显提高了骨组织中OPG mRNA表达,降低了RANK mRNA的表达。结论淫羊藿定对骨质疏松大鼠具有明显的治疗作用,其作用机制与提高骨组织中OPG mRNA表达,降低RANK mRNA的表达有关。

Objective To observe the therapeutic effect of epimedium on rats with osteoporosis caused by bilateral ovary and to explore its possible mechanism. Methods Forty-eight female Sprague-Dawley rats suffered removing bilateral ovaries and recovered for four weeks postoperatively to replicate a rat model of osteoporosis. They were randomly divided into four groups, namely epimedium high-dose group （800 mg/kg）, low-dose group （200 mg/kg） , calcitriol group （1 μg/kg） and model group （equal distilled water）. Another 12 rats were surgically stripped of the ovary but no ovaries were removed as a sham group （ equal distilled water）. Rats in each group were sacrificed after 12 weeks of continuous administration. The rat femur was taken and the bone density of the metaphyseal tip was measured with a bone densitometer. The change of bone tissue morphology was observed. Fluorescence quantitative PCR was used to detect the expression of OPG, RANK and RANKL mRNA in bone tissues. Results Epimedium significantly increased the bone density of the femoral metaphysis in rats with osteoporosis, which the trabecular bone densely distributed and neatly arranged, and increased the number of osteoblasts. At the same time, epimedium also significantly increased the OPG mRNA expression in bone tissue and decreased the RANK mRNA expression. Conclusion Epimedium has a significant therapeutic effect on osteoporotic rats. The mechanism is related to increasing the expression of OPG mRNA in bone tissue and reducing the expression of RANK mRNA.