摘要
目的基于肿瘤坏死因子-α(TNF-α)介导的Toll样受体4/核因子-κB(TLR4/NF-κB)信号通路,初步探讨原发性胆汁性胆管炎(PBC)模型小鼠的肠黏膜损伤机制。方法将40只C57BL/6雌性小鼠随机分为正常组和模型组,每组20只。采用聚肌胞苷酸[poly(I∶C)]5 mg/kg复制PBC小鼠模型。分别于给药8周、16周时处死小鼠(处死前禁食1 d),采集末端回肠以备检测。采用苏木精-伊红(HE)染色法观察回肠组织的病理变化,采用酶联免疫吸附试验(ELISA)方法检测回肠组织中TNF-α的表达水平,实时荧光定量逆转录-聚合酶链反应(qRT-PCR)方法测定回肠组织中TLR4mRNA、NF-κB mRNA的相对表达水平。结果随着造模时间的延长,模型组肠黏膜绒毛萎缩、变短、断裂,可见上皮下间隙增大、扩张,大量炎性细胞浸润于黏膜固有层甚至肌层,上皮层与固有层分离,伴随固有层毛细血管暴露,甚至出现固有层破坏、不完整,Chiu氏评分明显高于同期正常组(P均<0.01)。模型组肠组织中TNF-α水平高于同期正常组(P<0.01);与同期正常组相比,模型组肠组织中TNF-α、TLR4、NF-κB mRNA的表达水平较高(P均<0.01)。结论 PBC模型小鼠肠黏膜损伤机制与肠组织中TNF-α介导的TLR4/NF-κB信号通路密切相关。
Objective The injury mechanism of ileal mucosa of mice infected by primary biliary cholangitis（PBC）based on toll-like receptor 4/nuclear transcription factors-kappa B（TLR4/NF-kappa B）signal pathway induced by tumor necrosis factor-α（TNF-α）was studied.Methods 40 C57BL/6female mice were randomly divided into the normal group and the model group,20 in each group.The PBC animal model was established by injecting cytidine polyinosinic acid poly（I∶C）5 mg/kg to them.All mice were executed through cervical dislocation method after 8 and 16 weeks and fasted for 24 h before processing.The terminal ilea were taken out for detection.The HE staining was chosen to observe the ileum tissue pathological changes.Using the method of enzyme-linked immunosorbent assay（ELISA）,the protein molecule expression levels of TNF-αin ileum tissues were detected.Using the method of qRT-PCR,the expression levels of TLR4,NF-κB and TNF-αmRNA were detected.Results As time increases,the ileal mucosal villi got atrophied,shorter and fractured in the model group,with the epithelium clearance increased and expanded.A large number of inflammatory cells infiltrated in the mucosa lamina propria,even in the muscularis.Some epithelium and mucosa lamina propria were separated,along with the capillaries exposure in even incompleted mucosa lamina propria.The Chiu′s scores were significantly higher than that of the homeochronous normal group（P〈0.01）.The protein molecule expression levels of TNF-αin the model group were higher than those in the homeochronous normal group（P〈0.01）.Compared with the homeochronous normal group,the expression levels of TLR4,NF-κB and TNF-α mRNA in the model group were higher with a statistically significant difference（P〈0.01）.Conclusion TLR4/NF-κB signal pathway induced by TNF-αin the ileum tissue is closely correlated with the injury mechanism of ileal mucosa of mice infected with PBC.
作者
郭琲婷
郭晓霞
GUO Beiting GUO Xiaoxia(Department of Hepatology,Shanxi Research Institute of Traditional Chinese Medicine,Taiyuan 030012, China)
出处
《国际消化病杂志》
CAS
2017年第2期109-113,共5页
International Journal of Digestive Diseases
基金
山西省自然科学基金面上项目(2015011102)
