The Role of Crypt Fissioning in IBD Ulcer Healing

隐窝分裂在 IBD 溃疡愈合中的作用

• 批准号: 10358590
• 负责人: Terrence A. Barrett
• 金额: $ 66.28万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-02-24 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10358590
• 关键词: Biochemical; Biogenesis; Biopsy; Childhood; Chronic; Clinical; Clinical Data; Clinical Research; Colitis; Crohn' s disease; Data; Disease; Disease Outcome; Disease remission; Drops; Epithelial Cells; Failure; Gene Expression; Generations; Genes; Genetic Transcription; Genetically Engineered Mouse; Goals; Human; In Vitro; Inflammation; Inflammatory Bowel Diseases; Injury; Intestines; Investigation; Knockout Mice; Leukocyte L1 Antigen Complex; Maintenance; Measures; Mitochondria; Modeling; Monoclonal Antibodies; Mucositis; Mucous Membrane; Mus; Operative Surgical Procedures; Outcome; Oxidation-Reduction; PTEN gene; Pathogenesis; Patients; Phosphatidylinositols; Phosphotransferases; Principal Investigator; Procedures; Refractory; Respiration; Respiratory Chain; Role; Signal Transduction; Site; TNF gene; Tattooing; Testing; Treatment Efficacy; Ulcer; Ulcerative Colitis; Visualization; WNT Signaling Pathway; Work; base; beta catenin; chronic ulcer; clinical phenotype; crypt cell; dextran sulfate sodium induced colitis; drug development; experience; healing; infliximab; intestinal epithelium; new therapeutic target; novel; novel strategies; prevent; programs; prospective; repaired; response; single-cell RNA sequencing; stem cells; therapeutic biomarker; therapeutic target; transcriptomics

Program Director/Principal Investigator (Barrett, Terrence, A): The importance of mucosal healing in inflammatory bowel disease (IBD) derives from clinical data that demonstrate it to be a predictor of remission1. Thus, ulcer healing predicts the capacity for therapies to prevent unwanted clinical sequelae (i.e. surgery). Unfortunately, many IBD patients remain refractory or lose responsiveness to therapies leading to persistent mucosal ulceration. Prospective pediatric studies show that reduced mitochondrial gene expression predict unfavorable outcomes in ulcerative colitis (UC)2. These findings were supported by Kugathasan et al who found that increased expression of mitochondrial respiratory chain genes predicted favorable (B1 protected) Crohn’s disease (CD) outcomes3. Based on these results and our own data, we hypothesize that a critical driver of chronic ulceration in IBD is the failure of intestinal epithelial cells (IEC) to increase mitochondrial respiration with ROS generation. We posit that chronic mucosal inflammation suppresses mitochondrial respiration needed for crypt fissioning (in ulcer healing) in IBD. This hypothesis will be tested in the following studies: Aim 1. Determine the impact of mitochondrial respiration for mucosal healing. These studies benefit from strikingly novel Prelim. Data using VilCre/mTmG/TFAMfl/fl mice where mitochondrial respiration was shown to be required for crypt fissioning in ulcer healing. In Aim 2 we will determine the requirement of mitochondrial- derived ROS in IEC crypt division using primary human colonoids. Aim 3 studies will determine the impact of chronic inflammation on ulcer healing in patients. IEC transcriptomics from ulcer edges from CD and ulcerative colitis will be compared to normal ulcer healing. Normal ulcer healing will be interrogated using a novel biopsy of a biopsy (Bx/Bx) approach (IEC will be isolated from Bx/Bx sites 4-6day after initial biopsies). ScRNAseq results have already shown that mitochondrial biogenesis (PGC1) increases in Bx/Bx ulcers whereas levels drop in IBD IEC. In summary: Studies will investigate the cause of non-healing ulceration in IBD by interrogating novel murine, human and in vitro colonoid culture models of determining the impact of suppressed mitochondrial respiration on IEC responses (crypt fissioning). The studies will test the notion that chronic mucosal inflammation (as in IBD) suppresses mitochondrial respiration which impedes ROS-induced PI3K signaling and crypt fissioning. Our goal is to identify therapeutic targets to allow for enhanced mitochondrial respiration to aide mucosal repair in IBD. OMB No. 0925-0001/0002 (Rev. 01/18 Approved Through 03/31/2020) Page Continuation Format Page

项目总监/首席研究员（Barrett, Terrence, A）： 炎症性肠病 (IBD) 中粘膜愈合的重要性源自以下临床数据： 证明它是缓解的预测因子1。因此，溃疡愈合预测了治疗预防的能力 不必要的临床后遗症（即手术）。不幸的是，许多 IBD 患者仍然难治或失去治疗能力。 对治疗的反应导致持续性粘膜溃疡。前瞻性儿科研究表明 线粒体基因表达减少预示着溃疡性结肠炎 (UC)2 的不良后果。这些发现 得到了 Kugathasan 等人的支持，他们发现线粒体呼吸链的表达增加 基因预测有利的（B1 保护的）克罗恩病 (CD) 结果3。根据这些结果和我们的 根据我们自己的数据，我们假设 IBD 慢性溃疡的一个关键驱动因素是肠道功能衰竭 上皮细胞（IEC）通过ROS的产生来增加线粒体呼吸。我们假设慢性 粘膜炎症抑制隐窝裂变（溃疡愈合）所需的线粒体呼吸 炎症性肠病。该假设将在以下研究中得到检验： 目标 1. 确定 线粒体呼吸促进粘膜愈合。这些研究受益于引人注目的新颖 Prelim。 使用 VilCre/mTmG/TFAMfl/fl 小鼠的数据，其中线粒体呼吸被证明是必需的 溃疡愈合过程中隐窝裂变。在目标 2 中，我们将确定线粒体的需求- 使用原代人类结肠在 IEC 隐窝分裂中衍生出 ROS。目标 3 研究将确定 慢性炎症对患者溃疡愈合的影响。溃疡的 IEC 转录组学 CD 和溃疡性结肠炎的边缘将与正常溃疡愈合进行比较。溃疡愈合正常 将使用活检的新颖活检 (Bx/Bx) 方法进行询问（IEC 将与 Bx/Bx 位点（初次活检后 4-6 天）。 ScRNAseq 结果已经表明线粒体 Bx/Bx 溃疡中的生物发生 (PGC1) 增加，而 IBD IEC 中的水平下降。总结：研究 将通过询问新型小鼠、人类来调查 IBD 不愈合溃疡的原因 和体外结肠培养模型以确定线粒体呼吸抑制的影响 关于 IEC 响应（密码裂变）。这些研究将检验以下观点：慢性粘膜 炎症（如 IBD）抑制线粒体呼吸，从而阻碍 ROS 诱导的线粒体呼吸 PI3K 信号传导和隐窝裂变。我们的目标是确定治疗靶点以增强 线粒体呼吸有助于 IBD 粘膜修复。 OMB 编号 0925-0001/0002（修订版 01/18 批准至 03/31/2020） 页面延续格式页面