Suppr超能文献

肠致病性病原体鼠伤寒沙门氏菌和柠檬酸杆菌感染可调节肠道中的 TGF-β/Smad 信号通路。

Infection with enteric pathogens Salmonella typhimurium and Citrobacter rodentium modulate TGF-beta/Smad signaling pathways in the intestine.

机构信息

a Department of Medicine , Division of Gastroenterology & Hepatology, University of Illinois at Chicago , Chicago , IL , USA.

c Department of Physiology and Biophysics , University of Illinois at Chicago , Chicago , IL , USA.

出版信息

Gut Microbes. 2018 Jul 4;9(4):326-337. doi: 10.1080/19490976.2018.1429878. Epub 2018 Mar 27.

Abstract

Salmonella and Citrobacter are gram negative, members of Enterobacteriaceae family that are important causative agents of diarrhea and intestinal inflammation. TGF-β1 is a pleiotropic multifunctional cytokine that has been implicated in modulating the severity of microbial infections. How these pathogens alter the TGF-β1 signaling pathways in the intestine is largely unknown. Streptomycin-pretreated C57BL/6J mouse model colonized with S. typhimurium for 8 hours (acute) and 4 days (chronic) infection and FVB/N mice infected with C. rodentium for 6 days were utilized. Results demonstrated an increase in TGF-β1 receptor I expression (p<0.05) in S. typhimurium infected mouse ileum at both acute and chronic post-infection vs control. This was associated with activation of Smad pathways as evidenced by increased phosphorylated (p)-Smad2 and p-Smad3 levels in the nucleus. The inhibitory Smad7 mRNA levels showed a significant up regulation during acute phase of Salmonella infection but no change at 4d post-infection. In contrast to Salmonella, infection with Citrobacter caused drastic downregulation of TGF receptor I and II concomitant with a decrease in levels of Smad 2, 3, 4 and 7 expression in the mouse colon. We speculate that increased TGF-β1 signaling in response to Salmonella may be a host compensatory response to promote mucosal healing; while C. rodentium decreases TGF-β1 signaling pathways to promote inflammation and contribute to disease pathogenesis. These findings increase our understanding of how enteric pathogens subvert specific aspects of the host-cellular pathways to cause disease.

摘要

沙门氏菌和柠檬酸杆菌是革兰氏阴性菌,肠杆菌科的成员,是导致腹泻和肠道炎症的重要病原体。TGF-β1 是一种多功能细胞因子,参与调节微生物感染的严重程度。这些病原体如何改变肠道中的 TGF-β1 信号通路在很大程度上尚不清楚。利用链霉素预处理的 C57BL/6J 小鼠模型进行了急性(8 小时)和慢性(4 天)鼠伤寒沙门氏菌感染以及 FVB/N 小鼠进行了柠檬酸杆菌感染(6 天)。结果表明,在急性和慢性感染后,与对照组相比,鼠伤寒沙门氏菌感染的小鼠回肠中 TGF-β1 受体 I 表达增加(p<0.05)。这与 Smad 途径的激活有关,表现为核内磷酸化(p)-Smad2 和 p-Smad3 水平增加。在沙门氏菌感染的急性期,抑制性 Smad7 mRNA 水平显著上调,但在感染后 4 天没有变化。与沙门氏菌不同的是,柠檬酸杆菌感染导致 TGF 受体 I 和 II 的表达急剧下调,同时在小鼠结肠中 Smad2、3、4 和 7 的表达水平也降低。我们推测,沙门氏菌感染后 TGF-β1 信号的增加可能是宿主的一种代偿反应,以促进黏膜愈合;而柠檬酸杆菌降低 TGF-β1 信号通路以促进炎症并有助于疾病发病机制。这些发现增加了我们对肠道病原体如何颠覆宿主细胞途径的特定方面导致疾病的理解。

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验