雷公藤多苷片对溃疡性结肠炎小鼠结肠黏膜TLR4和NF-κB表达的影响

Effects of Tripterygium Glycosides Tablets on the Expression of TLR4 and NF-κB of Colonic Mucosa in Mice with Ulcerative Colitis

关键词:  雷公藤多苷片  葡聚糖硫酸钠  溃疡性结肠炎  TLR4  NF-κB

Key words:  Tripterygium Glycosides tablets  dextran sulfate sodium  ulcerative colitis  TLR4  NF-κB

摘要:

目的 观察雷公藤多苷片对右旋葡聚糖硫酸钠(dextran sulphate sodium，DSS)诱导的小鼠溃疡性结肠炎(ulcerative colitis，UC)模型结肠黏膜LPS/TLR4信号通路表达的影响，探讨其治疗UC的可能作用机制。方法 BALB/c小鼠随机分为6组：模型对照组，雷公藤多苷低、中、高剂量组、阴性对照组和正常对照组。采用葡聚糖硫酸钠复制UC小鼠模型，雷公藤多苷片混悬液灌胃给药21?d后，采用RT-PCR法检测TLR4 mRNA和蛋白的表达；采用Western Blot法测定NF-κB p65磷酸化水平；结肠组织冰冻切片进行免疫荧光双重染色，激光共聚焦显微镜观察NF-κB表达及分布。结果 雷公藤多苷各组较模型对照组TLR4表达水平显著降低(P<0.01)，中、高剂量组、阴性对照组与正常对照组比较，差异无统计学意义。与模型对照组比较，低剂量组NF-κB p65磷酸化水平略有下降，中、高剂量组下降明显，但差异均无统计学意义。结论 雷公藤多苷片能够通过抑制LPS/TLR4信号通路的表达，抑制UC小鼠的炎症反应，对UC发病起到一定的保护作用。

Abstract:

OBJECTIVE To observe the effects of Tripterygium Glycosides tablets on the expression of colon mucosa of LPS/TLR4 signaling pathway in mice with ulcerative colitis(UC) induced by dextran sulphate sodium(DSS), and to explore its possible mechanisms. METHODS BALB/c mice were randomly divided into 6 groups: model control group, low, middle and high dose of Tripterygium Glycosides tablets group, negative control group and normal control group. DSS was used to establish mice model of UC. Suspension of Tripterygium Glycosides tablets was administrated for 21 d. RT-PCR was adopted to detect the expression of TLR4 mRNA and protein. Western blotting was used to determine the phosphorylation level of NF-κB p65. Colon tissue frozen sections were stained by double immunofluorescence staining, and confocal laser confocal microscope was used to observe the expression and distribution of NF-κB. RESULTS The expression level of TLR4 of 3 groups of tripterygium glycosides was significantly decreased(P<0.01). Compared with normal control group, the expression level of TLR4 of middle and high dose of tripterygium glycosides and negative control group had no significant difference. Compared with model control group, the phosphorylation level of NF-κB p65 of low dose group decreased slighely,and decreased obviously in middle and high dose group, but there was no statistic difference(P>0.05). CONCLUSION The tripterygium glycosides tablets can inhibit the expression LPS/TLR4 signaling pathway and the inflammatory reaction in UC mice, and it had a certain protective effect on the pathogenesis of UC.