地塞米松对小鼠骨细胞白细胞介素-6及核因子κB受体活化因子配体表达的影响

Effect of dexamethasone on the expression of IL-6 and receptor activator for nuclear factor-κB ligand in mouse osteocytes

目的探讨地塞米松对体外培养的小鼠MLO-Y4骨细胞及脂多糖(LPS)刺激下小鼠骨细胞表达白细胞介素-6(IL-6)和核因子κB受体活化因子配体(RANKL)的影响。方法以10^(-6)、10^(-7) mol/L地塞米松作用MLO-Y4细胞,于24、48、72 h后检测细胞增殖;以不同浓度地塞米松刺激骨细胞4 h,采用实时荧光定量PCR检测细胞IL-6和RANKL的表达,用ELISA检测细胞IL-6的分泌。以10^(-7) mol/L地塞米松于不同时间点作用于MLO-Y4细胞,采用实时荧光定量PCR检测细胞IL-6和RANKL的表达,采用ELISA检测细胞IL-6的分泌。以10^(-7) mol/L地塞米松与100μg/L的LPS于不同时间点共同作用于MLO-Y4细胞,采用Real-time PCR检测细胞IL-6和RANKL的表达,采用ELISA检测细胞IL-6的分泌。结果 10^(-6) mol/L地塞米松抑制MLO-Y4细胞增殖,而10^(-7) mol/L地塞米松对细胞增殖无明显影响。除10^(-9) mol/L外,10^(-8)、10^(-7)、10^(-6) mol/L地塞米松均下调MLO-Y4细胞IL-6的表达。10^(-7) mol/L地塞米松能抑制LPS对MLO-Y4细胞IL-6表达的上调作用,且在8 h时最为明显。不同浓度及不同时间点地塞米松对MLO-Y4细胞RANKL的表达无明显影响。结论低浓度地塞米松可下调骨细胞及LPS刺激下的骨细胞IL-6的表达,而对RANKL表达无明显影响。

Objective To investigate the effect of dexamethasone on the expression of interleukin-6(IL-6)and receptor activator of nuclear factor-κB ligand(RANKL)in MLO-Y4 cells and on the expression of IL-6 and RANKL in MLO-Y4 cells stimulated by LPS.Methods MLO-Y4 cells were treated with 10^-6 mol/L and 10^-7 mol/L dexamethasone respectively,cell proliferation was detected after 24,48,and 72 hours by CCK8 assay.Treated MLO-Y4 cells with dexamethasone at different concentrations for 4 h.The expression of IL-6 and RANKL was detected by Real-time PCR,and the secretion of IL-6 was detected by ELISA.Treat MLO-Y4 cells with 10^-7 mol/L dexamethasoneat different time points.The expression of IL-6 and RANKL was detected by Real-time PCR,and the secretion of IL^-6 was detected by ELISA.MLO-Y4 cells were treated simultaneously with 10^-7 mol/L dexamethasone and 100μg/L LPS at different time points.IL-6 and RANKL expression was detected by qRT-PCR,detection of IL-6 secretion by ELISA.Results 10^-6 mol/L dexamethasone inhibited the proliferation of MLO-Y4 cells,while 10^-7 mol/L dexamethasone had nosignificant effect on cell proliferation.In addition to 10^-9 mol/L,dexamethasone at 10^-8,10^-7,and 10^-6 mol/L all down-regulated the relative expression of IL-6 in MLO-Y4 cells,10^-7 mol/L dexamethasone can down-regulate the relative expression of IL-6 in MLO-Y4 cells,10^-7 mol/L dexamethasone inhibited the up-regulation of IL-6 expression in MLO-Y4 cells by 100μg/L LPS,and this inhibition was the most significant at 8 h.Dexamethasone had no significant effect on the expression of RANKL in MLO-Y4 cells at different concentrations and different time points.Conclusion Low concentration of dexamethasone can down-regulate the expression of IL-6 in MLO-Y4 cells and MLO-Y4 cells stimulated by LPS,but has no obvious effect on the expression of RANKL.