Impact of probiotics on toll-like receptor 4 expression in an experimental model of ulcerative colitis
Impact of probiotics on toll-like receptor 4 expression in an experimental model of ulcerative colitis
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DOI：
10.1007/s11596-013-1177-9
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发表时间：
2013-10
期刊：
影响因子：
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通讯作者：
Xia Yang;Yu Fu;Jun Liu;Hongyu Ren
中科院分区：
文献类型：
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作者：
Xia Yang;Yu Fu;Jun Liu;Hongyu Ren
Toll 样受体 (TLR) 是先天免疫系统的关键组成部分，可触发抗菌宿主防御反应。本研究旨在探讨益生菌（乳酸菌、双歧杆菌）对三硝基苯磺酸（TNBS）/乙醇和免疫复合物诱导的大鼠实验性溃疡性结肠炎模型结肠黏膜TLR4和肿瘤坏死因子-α（TNF-α）表达的影响。通过均数标准差和独立样本检验来观察和评估结肠粘膜的大体和组织学变化。分别采用免疫组化和Western blotting检测TLR4和TNF-α的蛋白表达水平。结果显示，实验模型结肠组织中可见明显的炎性细胞浸润、隐窝脓肿形成、杯状细胞减少。与对照组比较，模型组TLR4和TNF-α蛋白水平显着升高（均P<0.01）。益生菌治疗两周组与模型组比较，TLR4、TNF-α表达无显着性差异（P>0.05），而益生菌治疗4周后，与模型组比较，TLR4、TNF-α表达显着降低（P<0.01）。两个益生菌治疗组之间没有显着差异。我们的结果表明，益生菌可能通过抑制实验模型结肠组织中 TLR4 的表达来减少炎症因子 TNF-α 的表达，从而在保护溃疡性结肠炎方面发挥关键作用。
Toll-like receptors (TLRs) are key components of the innate immune system which trigger antimicrobial host defense responses. This study aimed to investigate the impact of probiotics (Lactobacillus, Bifiidobacterium) on the expression of TLR4 and tumor necrosis factor-alpha (TNF-α) in the colon mucosa of rat experimental ulcerative colitis model induced by trinitrobenzene sulfonic acid (TNBS)/ethanol and immune complexes. The gross and histological changes of the colonic mucosa were observed and assessed by the means-standard deviation and independent samplest-test. The protein expression levels of TLR4 and TNF-α were detected by using immunohistochemistry and Western blotting, respectively. It was revealed that there was visible infiltration of inflammatory cells, formation of crypt abscess, and the reduction of goblet cells in the colon tissue of experimental models. As compared with the control group, the levels of TLR4 and TNF-α protein were significantly increased in the model group (P<0.01 for both). No significant difference was found in the expression of TLR4 and TNF-α between the two-week probiotics treatment group and the model group (P>0.05), whereas significant reductions were shown in rats which were treated with probiotics for four weeks as compared with the model group (P<0.01). There was no significant difference between two probiotics-treated groups. Our results implied that probiotics were likely to play a key role in protecting ulcerative colitis by reducing the inflammatory factor TNF-α expression through inhibiting the TLR4 expression in the colon tissue of experimental models.