Mechanisms of abnormal enterochromaffin cell secretion in Crohn's disease

克罗恩病肠嗜铬细胞分泌异常的机制

基本信息

批准号：
8230576
负责人：
Mark S Kidd
金额：
$ 31.75万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-03-01 至 2013-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8230576
关键词：
Acetylcholine Acetylmuramyl-Alanyl-Isoglutamine Address Adrenergic Agents Adrenergic Receptor Affect Agonist Amines Autoimmune Process CD14 Antigen CD4 Positive T Lymphocytes Cell physiology Cell secretion Cells Characteristics Chronic Disease Clinical Colitis Complex Crohn&apos s disease Cyclic AMP Cyclic AMP-Dependent Protein Kinases Cytokine Receptors Data Development Diffuse Disease Effector Cell Electrolytes Elements Endocrine Enteral Enterochromaffin Cells Enterocytes Enzymes Escherichia coli Etiology Event Exhibits Fluids and Secretions Functional disorder G-Protein-Coupled Receptors Genetic Transcription Health Human Hypersensitivity IL1R1 gene Immune In Vitro Infection Inflammation Inflammation Mediators Inflammatory Inflammatory Bowel Diseases Inflammatory Response Intestinal Motility Intestinal Secretions Intestines Knock-out Lipopolysaccharides Liquid substance MAP Kinase Gene Mechanical Stimulation Mechanics Mediating Modeling Morbidity - disease rate Mucous Membrane Mus Neuroendocrine Cell Neurosecretory Systems Norepinephrine Pain Pathogenesis Pathway interactions Patients Pattern Peptides Phenotype Phosphorylation Physiological Play Preparation Production Purinergic P1 Receptors Quality of life Receptor Activation Receptor Signaling Regulation Regulatory Element Role SECTM1 gene Sampling Serotonin Signal Pathway Signal Transduction Somatostatin Sorting - Cell Movement Subgroup Substance P Symptoms System TLR4 gene Techniques Time Transcript Tryptophan 5-monooxygenase absorption adrenergic cell motility cytokine gastrointestinal guanylin insight large bowel Crohn&apos s disease microbial new therapeutic target novel receptor receptor expression relating to nervous system response secretion process sensor somatostatin analog somatostatin receptor 1 therapeutic target

项目摘要

DESCRIPTION (provided by applicant): The gut neuroendocrine system is a key regulator of intestinal secretion, motility and pain, but its role in the symptoms, including secretory and motility abnormalities, mucosal damage, strictures and pain that characterize inflammatory bowel diseases (IBD), particularly Crohn's, has not been well-investigated. We propose that the most prevalent intestinal neuroendocrine cell, the enterochromaffin (EC) cell, plays a critical role in Crohn's symptomatology. The EC cell regulates normal intestinal motility and fluid secretion via secretion of serotonin (fluid and electrolyte secretion/pain), guanylin (enterocyte secretion) and substance P (motility/pain). Known effectors of normal EC cell function include luminal- and strain-sensing and neural (¿1-adrenergic) activation. The studies in this proposal will examine how inflammation-related products and mechanical stimulation activate NF?? and ERK signaling in EC cells and augment the secretory and motility symptomatology that characterizes Crohn's. We hypothesize that altered Crohn's EC cell activation and/or function are due to inflammatory-mediated events on the EC cell: either increased responsiveness to physiological ¿1-adrenergic- and strain mediated serotonin synthesis and secretion, or a loss of normal inhibitory responses to somatostatin and acetylcholine. Cytokines (particularly IL1¿) and bacterial lipopolysaccharides (LPS) and muramyl dipeptide (MDP) have been implicated in Crohn's pathogenesis through activation of TOLL4 receptor and IL1¿ receptor (TIL) and NOD2/CARD15 signaling. We propose that this system plays a pivotal role in abnormal Crohn's EC cell function via activation of signaling through NF??, and/or ERK pathways. The functional consequence would be an increase in transcription of the rate-limiting serotonin synthesizing enzyme, tryptophan hydroxylase (Tph-1), with a resultant increase in serotonin synthesis and secretion. Excess of serotonin and co-secreted products, guanylin and substance P, would produce increased secretion, motility and pain - all hallmarks of Crohn's disease. Additionally, loss of inhibitory regulation by somatostatin or acetylcholine might amplify these effects. In preliminary data, using FACS sorting, we produced pure (>99%), fully functional human and mouse (IL10R knockout) intestinal EC cells from normal and colitis mucosa. Using real-time PCR, we identified 5-fold increased transcripts for TLR4, 10-fold for IL1R¿, 2-fold for somatostatin receptors (1-3, 5) and 2-fold for the stimulatory mechano-responsive G-protein coupled receptor ADORA2B in human Crohn's EC cells. Both E. coli LPS and IL1¿ significantly increased 5HT secretion >2-fold in Crohn's EC cells. The NF?? and ERK phosphorylation signaled secretory responses were reversed by LPS and IL1¿ receptor antagonists (K12 LPS and IL1RA) and inhibited (80%) by a somatostatin analog in human samples. Cyclic strain application to EC cells resulted in 5HT release, induction of substance P and guanylin transcription in a time-dependent fashion. In the murine model, mucosal 5HT levels and Tph-1 transcripts were increased in colitis, TLR4 and IL1R¿ were expressed in colitis EC cells and both E. coli LPS and IL1¿ significantly increased 5HT secretion >3-fold. These results indicate that EC cell function is altered in Crohn's disease and that inflammatory mediators and mechanical strain play a direct role in increasing 5HT secretion. We propose to establish how EC cell activity is altered in Crohn's by: 1) determining whether 5HT, substance P and guanylin secretion is regulated by norepinephrine, mechanic forces somatostatin analogs and acetylcholine in Crohn's EC cells; 2) determining if ¿1-adrenergic and strain-mediated activation (cAMP signaling and PKA activation) is increased in Crohn's EC cells; 3) identifying whether the principal TIL/NOD2/CARD15 signaling pathway components, NF?? and ERK, are over-expressed in Crohn's EC cells and responsible for the elevated 5HT synthesis and secretion; and 4) Analyze EC cell function in a murine colitis model and evaluate whether inhibiting EC cell secretion ameliorates colitis symptoms. Crohn's is a common and chronic disease that substantially reduces quality of life. The understanding of the pathophysiology behind its often devastating symptomatology remains poorly understood. The identification and delineation of abnormal regulation of neuroendocrine cell function by the inflammatory response would provide novel information regarding the pathogenesis of Crohn's disease. In addition, it may provide the potential for novel therapeutic targets in Crohn's disease and possibly other forms of inflammatory bowel disease.

描述（由申请人提供）：肠道神经内分泌系统是肠道分泌、蠕动和疼痛的关键调节因子，但其在炎症性肠病（IBD）特征性症状中的作用，包括分泌和蠕动异常、粘膜损伤、狭窄和疼痛，特别是克罗恩病，尚未得到充分研究。我们认为最常见的肠道神经内分泌细胞，肠嗜铬细胞（EC）在其中发挥着关键作用。克罗恩病的症状学。 EC 细胞通过分泌血清素（液体和电解质分泌/疼痛）、鸟苷素（肠细胞分泌）和 P 物质（运动/疼痛）来调节正常的肠道运动和液体分泌。正常 EC 细胞功能的已知效应物包括管腔-。该提案中的研究将研究炎症相关产物和机械刺激如何激活。 EC 细胞中的 NF?? 和 ERK 信号传导，并增强了克罗恩病特征的分泌和运动症状，我们发现克罗恩病 EC 细胞激活和/或功能的改变是由于 EC 细胞上的炎症介导事件所致：对生理反应的反应性增加。 1-肾上腺素和菌株介导的血清素合成和分泌，或对细胞因子（特别是 IL1¿）和细菌脂多糖（LPS）和胞壁酰二肽（MDP）的正常抑制反应的丧失与克罗恩病的发病机制有关。 TOLL4 受体和 IL1 的激活¿受体 (TIL) 和 NOD2/CARD15 信号传导，我们认为该系统通过 NF?? 和/或 ERK 途径激活信号传导，在克罗恩氏 EC 细胞功能异常中发挥关键作用。限速血清素合成酶色氨酸羟化酶 (Tph-1)，导致血清素合成和分泌过量。共同分泌的产物鸟苷酸和 P 物质会增加分泌、运动和疼痛——这些都是克罗恩病的标志。此外，生长抑素或乙酰胆碱的抑制调节的丧失可能会放大这些效应。我们使用实时 PCR 鉴定了来自正常和结肠炎粘膜的纯（> 99％）、功能齐全的人类和小鼠（IL10R 敲除）肠道 EC 细胞。 TLR4 的转录物增加 5 倍，IL1R 的转录物增加 10 倍¿ ，生长抑素受体 (1-3, 5) 的 2 倍和人克罗恩氏 EC 细胞中刺激性机械响应 G 蛋白偶联受体 ADORA2B 的 2 倍。大肠杆菌 LPS 和 IL1¿克罗恩氏 EC 细胞中 5HT 分泌显着增加 2 倍，LPS 和 IL1¿ 逆转了 NF?? 和 ERK 磷酸化信号的分泌反应。受体拮抗剂（K12 LPS 和 IL1RA）并被人类样本中的生长抑素类似物抑制（80%）。在小鼠中，对 EC 细胞进行循环菌株应用会导致 5HT 释放、P 物质和鸟苷蛋白转录的诱导。模型中，结肠炎、TLR4 和 IL1R 中粘膜 5HT 水平和 Tph-1 转录物增加？在结肠炎 EC 细胞以及大肠杆菌 LPS 和 IL1 中表达5HT 分泌显着增加 >3 倍。这些结果表明克罗恩病中 EC 细胞功能发生改变，并且炎症介质和机械应变在增加 5HT 分泌中发挥直接作用，我们建议通过以下方式确定克罗恩病中 EC 细胞的活性： 1)确定克罗恩病EC中5HT、P物质和鸟苷素的分泌是否受去甲肾上腺素、机械力生长抑素类似物和乙酰胆碱的调节细胞；2) 确定是否 ¿克罗恩氏 EC 细胞中 1-肾上腺素能和应变介导的激活（cAMP 信号传导和 PKA 激活）增加；3) 确定主要的 TIL/NOD2/CARD15 信号通路成分 NF?? 和 ERK 在克罗恩氏 EC 中是否过度表达细胞并负责增加 5HT 合成和分泌；4) 分析小鼠结肠炎模型中的 EC 细胞功能并评估是否抑制 EC 细胞分泌改善结肠炎症状。克罗恩病是一种常见的慢性疾病，可显着降低生活质量。对其经常具有破坏性的症状背后的病理生理学的了解仍知之甚少，而对炎症反应对神经内分泌细胞功能异常调节的识别和描述将提供新的思路。此外，它还可能为克罗恩病和其他形式的炎症性肠病提供新的治疗靶点。

项目成果

期刊论文数量（17）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

The clinical implications and biologic relevance of neurofilament expression in gastroenteropancreatic neuroendocrine neoplasms.

胃肠胰神经内分泌肿瘤中神经丝表达的临床意义和生物学相关性。

DOI：
发表时间：
2012-05-15
期刊：
影响因子：
6.2
作者：
Schimmack, Simon;Lawrence, Ben;Svejda, Bernhard;Alaimo, Daniele;Schmitz;Fischer, Lars;Buchler, Markus W;Kidd, Mark;Modlin, Irvin
通讯作者：
Modlin, Irvin

EGFR/TGFα and TGFβ/CTGF Signaling in Neuroendocrine Neoplasia: Theoretical Therapeutic Targets.

神经内分泌肿瘤中的 EGFR/TGFα 和 TGFβ/CTGF 信号传导：理论治疗目标。