目的 探讨漆黄素对去卵巢大鼠骨质疏松症的影响.方法 将50 只雌性SD大鼠采取双侧卵巢切除法构建骨质疏松症模型,分为模型组、漆黄素10、20、40 mg/kg组及阳性对照组,每组 10 只.漆黄素组给予不同浓度漆黄素干预,阳性对照组给予雌二醇(E2)干预,连续8 周.另选10 只大鼠作为假手术组.检测各组大鼠血清碱性磷酸酶(ALP)、骨钙素(OCN)、E2、Ⅰ型胶原羧基 C 端交联肽(CTX-Ⅰ)、骨 γ-羧基谷氨酸蛋白(BGP)以及骨密度(BMD),HE染色观察骨组织形态学,采用Micro-CT测定骨指标[骨体积分数(BV/TV)、骨小梁厚度(Tb.Th)、骨小梁分离度(Tb.Sp)、骨小梁数目(Tb.N)],采用生物力学材料实验机检测骨生物力学参数(股骨颈加载力、胫骨轴强度、腰椎压缩力),Western-blot 检测 Runt 相关转录因子 2(Runx2)、低密度脂蛋白受体相关蛋白-5(Lrp-5)、β-联蛋白(β-catenin)和成骨细胞特异性转录因子Osterix(Osx)表达水平.结果 与假手术组比较,模型组ALP、OCN、Tb.Sp、CTX-Ⅰ显著升高,E2、BMD、BV/TV、Tb.Th、Tb.N、BGP、股骨颈加载力、胫骨轴强度、腰椎压缩力、Runx2、Lrp-5、β-catenin、Osx水平显著降低(P<0.05);HE染色显示股骨骨小梁排列疏松、网状结构破坏、小梁数减少且断裂点增多.与模型组比较,漆黄素40 mg/kg组及阳性对照组ALP、OCN、Tb.Sp、CTX-Ⅰ显著降低,E2、BMD、BV/TV、Tb.Th、Tb.N、BGP、股骨颈加载力、胫骨轴强度、腰椎压缩力、Runx2、Lrp-5、β-catenin、Osx水平显著升高(P<0.05);HE染色显示股骨骨小梁排列及网状结构明显恢复,有较高的骨连接.结论 漆黄素可提高去势骨质疏松大鼠骨应力,其作用机制可能与促进Wnt/β-catenin蛋白通路、降低大鼠体内高骨转换速率有关.
Objective To investigate the effects of Fisetin on osteoporosis in rats undergoing ovariectomy.Methods A total of 50 female SD rats were treated with bilateral ovariectomy to construct a model of osteoporosis,and divided into model group,Fisetin 10 mg/kg group,Fisetin 20 mg/kg group,Fisetin 40 mg/kg group and positive control group,with 10 rats in each group.Fisetin group was given different concentrations of Fisetin intervention,and the positive control group was given estradiol(E2)for 8 consecutive weeks.Another 10 rats were selected as sham operation group.Serum alkaline phos-phatase(ALP),osteocalcin(OCN),E2,carboxyl C-terminal cross-linked peptide of type Ⅰ collagen(CTX-Ⅰ),bone γ-carboxyl glutamate protein(BGP)and bone mineral density(BMD)were detected in each group.Bone morphology was ob-served by HE staining.Bone indexes[bone volume fraction(BV/TV),trabecular thickness(Tb.Th),trabecular separation(Tb.Sp),trabecular number(Tb.N)]were detected by micro-CT,and bone biomechanical parameters(femoral neck load-ing force,strength of tibial axis,lumbar compression force)were detected by Micro-CT.The expression levels of Runt-associ-ated transcription factor 2(Runx2),low-density lipoprotein receptor-associated protein-5(Lrp-5),β-catenin and osteoblast-specific transcription factor Osterix(Osx)were detected by Western blot.Results Compared with sham operation group,ALP,OCN,Tb.Sp and CTX-Ⅰ in model group were significantly increased.The levels of E2,BMD,BV/TV,Tb.Th,Tb.N,BGP,femoral neck loading force,strength of tibial axis,lumbar compression force,Runx2,Lrp-5,β-catenin and Osx were significantly decreased(P<0.05).HE staining showed loose arrangement of trabeculae,destruction of reticular struc-ture,reduction of trabecular number and increase of fracture points.Compared with model group,ALP,OCN,Tb.Sp and CTX-Ⅰin Fisetin 40 mg/kg group and positive control group were significantly decreased.The levels of E2,BMD,BV/TV,Tb.Th,Tb.N,BGP,femoral neck loading force,strength of tibial axis,lumbar compression force,Runx2,Lrp-5,β-catenin and Osx were significantly increased(P<0.05).HE staining showed that the trabecular arrangement and reticular structure of the femoral bone were obviously restored,and there were higher bone connections.Conclusion Fisetin can improve bone stress in osteoporosis rats after ovariectomy,and its mechanism of action is related to promoting Wnt/β-catenin pathways and reducing rate of high bone turnover.