葛根素对去卵巢大鼠骨代谢平衡的影响

Influence of Puerarin on Bone Metabolic Equilibrium in Ovariectomized Rats

目的:探讨葛根素对去卵巢大鼠骨代谢平衡的影响。方法:将SPF级雌性Wistar大鼠60只按随机数字表法分为空白组、模型组、雌二醇组及葛根素组各15只。除空白组外,其余大鼠采用去卵巢法建立骨质疏松模型。造模成功后,空白组和模型组均皮下注射生理盐水,雌二醇组皮下注射雌二醇,葛根素组皮下注射葛根素,各组均每天注射1次,连续4周。4周后采用酶联免疫法检测各组大鼠血清骨代谢标志物骨特异性碱性磷酸酶(bone specific alkaline phosphatase,BALP)、核结合因子α1(core binding factorα1,CBF-α1)、Ⅰ型胶原羧基末端肽(Cterminal typeⅠcollagen telopeptide,CTX-I)、Ⅰ型前胶原氨基端前肽(procollagen typeⅠamino-terminal peptide,PINP)、骨钙素(osteocalcin,OC)含量;采用显微CT影像观察各组大鼠股骨远端骨密度水平及骨小梁微结构,并进行计量学分析;采用WB法检测各组大鼠股骨及下丘脑组织骨形态发生蛋白2(bone morphogenet protein-2,BMP-2)和血管内皮生长因子(vascular endothelial growth factor,VEGF)蛋白表达。结果:与空白组相比,模型组大鼠骨密度降低,骨代谢标志物BALP、CBF-α1、CTX-I、PINP、OC含量均减少(P<0.05);股骨远端相对骨体积分数(BV/TV)、骨小梁数量(Tb.N)、骨小梁厚度(Tb.Th)、连接密度(Conn.D)、骨小梁分离度(Tb.Sp)均减少(P<0.05),结构模型指数(SMI)均增加(P<0.05);股骨及下丘脑组织BMP-2均减少(P<0.05),VEGF蛋白均增加(P<0.05)。干预4周后,与模型组比较,雌二醇组与葛根素组大鼠骨密度、骨小梁微结构及骨代谢标志物均改善(P<0.05),骨强度及弹性均增加(P<0.05);骨组织BMP-2蛋白表达升高(P<0.05),VEGF蛋白表达降低(P<0.05)。雌二醇组和葛根素组大鼠骨密度、骨代谢标志物含量、骨小梁结构参数、股骨及下丘脑组织中BMP-2和VEGF各指标比较差异无统计学意义(P>0.05)。结论:葛根素能够改善去卵巢大鼠骨代谢水平,增加骨量,改善骨小梁微结构,效果与雌二醇相当。

Objective:To discuss the effects of puerarin on bone metabolic equilibrium in ovariectomized rats.Methods:Sixty SPF grade female Wistar rats were divided into the blank group,the model group,estradiol group and puerarin group in light of random number table method,with 15 ones in each group.Except for the blank group,the other rats were prepared into osteoporosis models by ovariectomy.After successfully modeling,the blank group and the model group accepted subcutaneous injection of physiological saline,estradiol group subcutaneous injection of estradiol and puerarin group subcutaneous injection of puerarin,all the groups were injected once a day for four consecutive weeks.ELISA method was used to detect the contents of serum bone metabolism markers including BALP,CBF-α1,CTX-1,PINP and OC of the rats in in different groups after four weeks;microscopic CT imaging was adopted to observe bone mineral density(BMD)and trabecular microstructure of distal femur of the rats in different groups,and to carry out metrology analysis;WB method was utilized to measure the expressions of BMP-2 and VEGF in femur and hypothalamic tissue of the rats in different groups.Results:Compared with the blank group,BMD of the rats lowered in the model group,the contents of bone metabolism markers such as BALP,CBF-α1,CTX-1,PINP and OC reduced(P<0.05);bone volume/total volume of distal femur(BV/TV),the number of bone trabecula(Tb.N),bone trabecular thickness(Tb.Th),connectivity density(Conn.D)and trabecular separation(Tb.Sp)decreased(P<0.05),structural model index(SMI)increased(P<0.05);the expressions of BMP-2 lowered in femur and hypothalamic tissue(P<0.05),VEGF protein increased(P<0.05).After four weeks of intervention,compared with the model group,BMD,trabecular microstructure and bone metabolic markers improved in estradiol group and puerarin group(P<0.05),bone strength and elasticity enhanced(P<0.05);the expressions of BMP-2 protein increased in bone tissue(P<0.05),the expressions of VEGF protein reduced(P<0.05).The difference had no statistical meaning in BMD,the corolehts of bone metabolism markers,the structural parameters of the trabecular bone,the levels of BMP-2 and VEGF in femur and hypothelamic between estradiol group and puerarin group(P>0.05).Conclusion:Puerarin could improve the levels of bone metabolism in ovariectomized rats,increase bone mass,and improve trabecular microstructure,its effects are equivalent to estradiol(P>0.05).