葛根素缓解镉对大鼠股骨胫骨中成骨细胞分化的抑制作用

Puerarin Alleviates the Inhibitory Effect of Cadmium on the Femoral and Tibial Osteoblast Differentiation of Rat

旨在探究葛根素对镉(cadmium,Cd)抑制大鼠股骨胫骨中成骨细胞(osteoblast,OB)分化的缓解效应。选取40只3周龄SD雄性大鼠,随机分为4组,分别为对照组(CON)、镉组(Cd)、葛根素组(Pur)和镉+葛根素组(Cd+Pur),每组10只。其中,对照组和镉组大鼠灌服超纯水,连续5周;含葛根素组(葛根素组和镉+葛根素组)大鼠每日灌服葛根素溶液(200 mg·kg-1BW),连续5周;从第5周开始,对照组与葛根素组大鼠每日腹腔注射生理盐水,含镉组(镉组和镉+葛根素组)大鼠每日腹腔注射醋酸镉(2.5 mg·kg^(-1)BW),连续1周。通过原子吸收光谱法检测大鼠股骨胫骨中Cd、钙(Ca)与磷(P)的含量,qRT-PCR方法检测OB标志基因(RUNX2、OCN、ALP和OSX)的水平,Western blot检测Wnt/β-catenin信号通路相关蛋白(β-catenin、Wnt3A、LEF1和TCF1)的表达。结果显示,与对照组相比,镉组股骨和胫骨中镉含量极显著上调(P<0.01),OB标志基因均下调,Wnt/β-catenin信号通路相关蛋白极显著下调(P<0.01),但Ca和P含量无显著变化(P>0.05);葛根素组股骨胫骨中镉、Ca与P含量无显著变化(P>0.05),OB标志基因(RUNX2、ALP和OCN)极显著上调(P<0.01),Wnt/β-catenin信号通路相关蛋白极显著上调(P<0.01);与镉组相比,镉+葛根素组股骨胫骨中镉含量极显著下调(P<0.01),OB标志基因极显著上调(P<0.01),Wnt/β-catenin信号通路相关蛋白极显著上调(P<0.01),但骨中Ca与P含量无显著变化(P>0.05)。结果表明,葛根素对镉抑制大鼠OB分化具有一定的缓解效应,该过程涉及Wnt/β-catenin信号通路。

The aim of this study was to investigate the alleviation effect of puerarin on the differentiation of osteoblasts inhibited by cadmium(Cd)in rat femur and tibia.Forty 3-week-old SD male rats were randomly divided into 4 groups with 10 rats per group:control group(CON),cadmium group(Cd),puerarin group(Pur)and cadmium plus puerarin group(Cd+Pur).The rats in the control group and the cadmium group were gavaged with ultrapure water for 5 consecutive weeks.The rats related to puerarin group(puerarin group and cadmium plus puerarin group)were gavaged with puerarin solution(200 mg·kg-1BW)daily for 5 consecutive weeks.From the fifth week,rats in control group and puerarin group were intraperitoneally injected with normal saline,and the cadmium containing groups(cadmium group and cadmium plus puerarin group)were intraperitoneally injected with cadmium acetate(2.5 mg·kg^(-1)BW)daily for 1 consecutive week.The contents of cadmium,calcium(Ca)and phosphorus(P)of the femur and tibia in rats were detected by atomic absorption spectrometry.The level of osteoblastic marker genes(RUNX2,OCN,ALP and OSX)were detected by qRT-PCR.The expression of Wnt/β-catenin signaling pathway-related proteins(β-catenin,Wnt3A,LEF1 and TCF1)were detected by Western blot.The results showed that the content of Cd of the femur and tibia in cadmium group was significantly up-regulated(P<0.01),the level of osteoblastic marker genes were down-regulated,the expression of Wnt/β-catenin signaling pathway-related proteins were extremely significantly down-regulated(P<0.01)compared with the control group,but the content of Ca and P were not significantly changed(P>0.05).The content of Cd,Ca and P of the femur and tibia in puerarin group was not significantly changed(P>0.05),the level of osteoblastic marker genes(RUNX2,ALP and OCN)were extremely significantly up-regulated(P<0.01),and the expression of Wnt/β-catenin signaling pathway-related proteins were extremely significantly up-regulated(P<0.01).The content of Cd of the femur and tibia in the cadmium plus puerarin group was extremely significantly down-regulated(P<0.01),the level of osteoblastic marker gene was extremely significantly up-regulated(P<0.01),and the Wnt/β-catenin signaling pathway-related proteins were extremely significantly up-regulated(P<0.01)compared with the cadmium group,but the content of Ca and P in the femur and tibia had no significant changes(P>0.05).The results showed that puerarin had an alleviation effect on the differentiation of osteoblasts inhibited by cadmium in rats,which was involved in Wnt/β-catenin signaling pathway.