Mechanism of dietary indole-mediated attenuation Helicobacter-induced inflammation and colitis

项目总结/摘要 炎症性肠病（IBD）困扰着超过一百万的美国人，造成相当大的痛苦和损失。 工作时间。2014年IBD的直接和间接成本估计在146亿至316亿美元之间。 此外，IBD大大增加了患结直肠癌的风险。现在人们认为细菌 IBD和结直肠癌的关键参与者。许多螺杆菌感染人结肠， 已知在结肠炎易感小鼠品系中引起结肠炎和结肠癌。我们有令人兴奋的数据显示， H.在野生型小鼠中，鼠伤寒沙门氏菌加重葡聚糖硫酸钠（DSS）诱导的结肠炎。没有研究 H引发的免疫反应muridarum。因此，这种EHH物种提供了一个独特的实验模型， 以了解结肠炎是如何在免疫正常的动物在化学损伤后引发的。最近 研究表明，饮食吲哚，如吲哚-3-甲醇（I3 C），来源于十字花科蔬菜， 具有多种抗炎和抗癌特性。我们的初步研究表明，I3 C 使H.小鼠+DSS介导的结肠炎和结肠炎症的恶化。而且我们 注意到I3 C处理降低了靶向FOXP 3的miR-874的表达，并增加了靶向FOXP 3的miR-874的表达。 30 b，其靶向RORC（RORγt）以及增加靶向IL-17的miR-5112。根据这些数据，在 在本研究中，我们将检验I3 C减弱H. 通过miR表达的改变促进T细胞从Th 17分化的转换， 到Tennis。H. muridarum也是未知的。 因此，了解IBD中针对螺杆菌的免疫应答的性质至关重要。与 最后，我们将同时探讨这两种药物引起的免疫和调节变化。第一、 我们将检查在DSS介导的结肠炎中发生的T细胞应答，有和没有H。穆里达鲁姆 感染以及有和没有I3 C治疗。我们的主要重点将是调节性T细胞（Treg），这是至关重要的 来维持肠道的平衡接下来，我们将确定H。在芳香烃中，鼠伤寒可引起结肠炎 受体（AhR）缺陷小鼠，其不能产生足够的TdR，并且更容易患结肠炎。这些 小鼠也将用于测试已知作为AhR配体的I3 C的功效。最后我们将 确定由I3 C诱导的特定microRNA种类是否通过改变 FoxP 3在体外和体内的表达。总之，从这些实验中获得的见解将是必不可少的 了解I3 C的作用机制，并可能导致额外的高度靶向治疗。这 项目不仅将表征H. DSS诱导的小鼠 结肠炎，而且还测试I3 C对H的作用模式。与鼠粪相关的结肠炎。这些数据将支持未来 研究其他螺杆菌在临床IBD中的作用以及I3 C在IBD中的潜在用途 IBD的治疗。

Project Summary/Abstract Inflammatory bowel disease (IBD) afflicts over one million Americans, causing considerable suffering and lost work time. The direct and indirect costs of IBD were estimated to be between $14.6 and $31.6 billion in 2014. Furthermore, IBD greatly increases the risk of developing colorectal cancer. Bacteria are now believed to be key players in both IBD and colorectal cancer. A number of Helicobacter species infect the human colon and are known to cause colitis and colon cancer in colitis-prone mouse strains. We have exciting data showing that H. muridarum exacerbates dextran sulfate sodium (DSS) induced colitis in wild-type mice. There are no studies on the immune response triggered by H. muridarum. Thus, this EHH species offers a unique experimental model to understand how colitis is triggered in an immunologically normal animal following a chemical insult. Recent studies have shown that dietary indoles, such as Indole-3-carbinol (I3C), derived from cruciferous vegetables, have a number of anti-inflammatory and anti-carcinogenic properties. Our preliminary studies showed that I3C attenuates H. muridarum+DSS-mediated exacerbation of colitis and inflammation in the colon. Furthermore, we noted that I3C treatment decreases the expression of miR-874, which targets FOXP3, and increases that of miR- 30b which targets for RORC (RORγt) as well as increases miR-5112 that targets IL-17. Based on these data, in the current study, we will test the central hypothesis that I3C attenuates colitis and inflammation induced by H. muridarum through alterations in the expression of miRs that promote a switch in T cell differentiation from Th17 to Tregs. The mechanisms of colitis exacerbation involving inflammation by H. muridarum are also not known. Thus, it is critical to understand the nature of immune response against Helicobacter species in IBD. To that end, we will simultaneously explore immunological and regulatory changes induced by these two agents. First, we will examine the T cell responses occurring during DSS-mediated colitis with and without H. muridarum infection and with and without I3C treatment. Our primary focus will be regulatory T cells (Treg), which are critical for intestinal homeostasis. Next, we will determine whether H. muridarum can trigger colitis in Aryl hydrocarbon receptor (AhR)-deficient mice which fail to generate enough Tregs and are more susceptible to colitis. These mice will also be used to test the efficacy of I3C, which has been known to act as an AhR ligand. Finally, we will determine whether specific microRNA species induced by I3C contribute to the Treg response by changing FoxP3 expression both in vitro and in vivo. Together, the insights gained from these experiments will be essential for understanding the mechanisms of action of I3C and could lead to additional highly targeted treatments. This project will not only characterize the nature of immune response triggered by H. muridarum during DSS-induced colitis but also test the mode of action of I3C on H. muridarum-associated colitis. These data will support future explorations to investigate the role of other Helicobacter species in clinical IBD and the potential use of I3C in the treatment of IBD.