薯蓣皂苷通过ERα/miR503/RANK信号通路抑制破骨细胞生成

Dioscin inhibits osteoclastogenesis via ERα/miR503/RANK signaling pathway

目的探究薯蓣皂苷对小鼠破骨细胞前体细胞(RAW264.7)破骨分化的抑制作用以及潜在机制。方法利用核因子κB受体活化因子配体(RANKL)诱导的RAW264.7破骨分化模型,设置模型对照组、雌激素组、薯蓣皂苷低剂量组、薯蓣皂苷高剂量组,通过CCK8法检测不同浓度薯蓣皂苷对细胞的毒性作用,通过TRAP染色进行破骨细胞计数,qPCR检测细胞中ERα/miR503/RANK信号通路及破骨标志性基因TRAP、MMP9、CTSK基因表达水平,Western blot检测细胞中ERα、RANK蛋白表达水平。结果薯蓣皂苷对RAW264.7细胞无明显毒性作用。与模型对照组比较,高剂量薯蓣皂苷组及雌激素组的TRAP阳性细胞数目下降(P<0.05),薯蓣皂苷及雌激素上调了ERα、miR-503-5p的表达水平,抑制了RANK的表达水平,下调了破骨标志性基因的表达(P<0.05)。结论薯蓣皂苷可能通过ERα/miR-503/RANK信号通路下调破骨标志性基因,从而抑制RAW264.7细胞破骨分化。

Objective To investigate the inhibitory effect of dioscin on osteoclastic differentiation of mouse osteoclast precursor cells(RAW264.7)and the potential mechanism.Methods RAW264.7 cells were induced with receptor activator of nuclear factorκB ligand(RANKL).RAW264.7 cells were divided into model control group,estrogen group,dioscin low dose group,and dioscin high dose group.The toxicity of dioscin on RAW264.7 cells was detected using CCK-8 assay.TRAP staining was performed for osteoclast counting.qPCR was used to detect the expression levels of estrogen receptorα(ERα),miR-503-5p,nuclear transcription factor-κB receptor(RANK),and osteoclast signature genes TRAP,MMP9,and CTSK in the cells.Western blotting was performed to detect the protein expression levels of ERαand RANK.Results Dioscin had no significant toxic effect on RAW264.7 cells.Compared to those in the model control group,the number of TRAP-positive cells decreased in the high-dose dioscin and estrogen groups(P<0.05).Dioscin and estrogen up-regulated the expression levels of ERαand miR-503-5p,inhibited the expression level of RANK,and down-regulated the expression of signature genes of osteoclast(P<0.05).Conclusion Dioscin inhibits osteoclastic differentiation of RAW264.7 cells by down-regulating osteoclastic signature genes through the ERα/miR-503/RANK signaling pathway.