Mechanisms of essential calcium signaling during gastric epithelial wound healing

胃上皮伤口愈合过程中必需的钙信号传导机制

• 批准号: 9033115
• 负责人: MARSHALL H MONTROSE
• 金额: $ 35.55万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9033115
• 关键词: Actins; Agonist; Anti-Inflammatory Agents; Anti-inflammatory; Biochemical; Biological Assay; CDC42 gene; Calcium Signaling; Cell Line; Cells; Cellular Structures; Cytoskeleton; Dependence; Dinoprostone; Employee Strikes; Epithelial; Epithelium; Event; Exposure to; Gases; Gastritis; Healed; Health; Healthcare Systems; Helicobacter Infections; Helicobacter pylori; Image; In Vitro; Infection; Intervention; Lead; Learning; Lesion; Link; MYLK gene; Measures; Mediating; Microscopic; Modeling; Molecular; Monomeric GTP-Binding Proteins; Mus; NHE2; Optics; Organoids; Outcome; Pathogenesis; Pathology; Pathway interactions; Peptic Ulcer; Pharmaceutical Preparations; Phospholipase C; Process; Prostaglandin-Endoperoxide Synthase; Prostaglandins; Protein Kinase C; Pylorus; Regulation; Role; Signal Pathway; Signal Transduction; Speed; Stomach; Surface; Technology; Testing; Therapeutic; Tight Junctions; Time; Tissues; Toxic effect; Ulcer; Work; Wound Healing; base; cell motility; citrate carrier; extracellular; healing; improved; in vivo; inhibitor/antagonist; innovation; irritation; loris; migration; pathogen; repaired; research study; response; rho; tool; upper GI series

 DESCRIPTION (provided by applicant): Peptic ulcer disease and upper GI irritation are a significant burden in the US healthcare system and worldwide, caused in large part by the upper GI toxicity of ingested non-steroidal anti-inflammatory drugs (NSAIDs) and the pathogen H. pylori. The rationale for our work is that improved or alternative therapeutic strategies can be based on understanding the mechanisms of gastric defense rallied against such challenges. Preliminary studies show an essential role for both intracellular and extracellular Ca2+ mobilization in gastric repair of the surface epithelium. We hypothesize that this Ca2+ mobilization is a central regulator of repair that underlies the effects of diverse agonists shown to modulate the repair process, and that this pathway can be disrupted by NSAIDs and H. pylori. The objective of this application is to use the newly identified Ca2+ signals as heralds to identif the underlying upstream and downstream mechanisms mediating gastric repair, and as a tool to investigate if NSAIDs and/or H. pylori compromise repair via these pathways. We have pioneered optical technologies that allow real-time creation of focal damage and continual quantification of repair. Our work focusing on the repair of focal lesions in vivo will be extrapolated to experiments evaluating ulceration to enhance relevance to gastric pathologies observed clinically, and to study of gastric organoids as a potentially powerful new model of gastric epithelial function. Our first aim is to identify the initiating extracellular signals in damaged tissue that stimulate Ca2+ mobilization and gastric repair. We will focus on TFF2 and prostaglandins, shown to be essential to gastric repair, but whose role in Ca2+ signaling is untested. The second aim establishes the hierarchy of Ca2+-dependent intracellular signaling pathways that are essential to allow repair. Experiments are based on preliminary findings that show phospholipase C, and protein kinase C are required for efficient gastric repair in the intact stomach. Our third aim evaluates the downstream targets of Ca2+- dependent signaling that perform the work of gastric repair. We will evaluate the role of the NHE2 Na/H exchanger, shown to be essential for gastric repair as a downstream effector of TFF2. We will also evaluate Ca2+ -dependent regulation of the actin cytoskeleton, tight junctions, and the small GTPases that regulate these cellular structures during repair. All aims focus on the role of the cyclooxygenase (COX)/prostaglandin pathway inhibited by NSAIDs, and the first and third aims additionally examine changes in the studied pathways caused by infection with H. pylori. The outcomes will provide a unique window into understanding early factors in gastric pathogenesis, which have potential to lead to new targets and new strategies for interventions that can minimize gastric damage and speed healing.

 描述（由申请人提供）：消化性溃疡病和上消化道刺激是美国医疗保健系统和全世界的一个重大负担，很大程度上是由摄入的非甾体抗炎药 (NSAID) 和病原体幽门螺杆菌的上消化道毒性引起的。我们工作的基本原理是，改进或替代的治疗策略可以基于了解针对此类挑战的胃防御机制。初步研究表明细胞内和细胞外 Ca2+ 动员在胃表面上皮修复中发挥着重要作用。我们假设这种 Ca2+ 动员是修复的中心调节因子，是调节修复过程的多种激动剂作用的基础，并且该途径可以被 NSAID 和幽门螺杆菌破坏。该应用的目的是使用新识别的 Ca2+ 信号作为先兆来识别介导胃修复的潜在上游和下游机制，并作为研究 NSAID 和/或幽门螺杆菌是否通过这些途径损害修复的工具。我们开创了光学技术，可以实时创建焦点损伤并持续量化修复。我们专注于体内局灶性病变修复的工作将推广到评估溃疡的实验，以增强与临床观察到的胃病理学的相关性，并研究胃类器官作为胃上皮功能的潜在强大的新模型。我们的首要目标是确定受损组织中刺激 Ca2+ 动员和胃修复的起始细胞外信号。我们将重点关注 TFF2 和前列腺素，它们被证明对胃修复至关重要，但其在 Ca2+ 信号传导中的作用尚未经过测试。第二个目标是建立 Ca2+ 依赖性细胞内信号通路的层次结构，这对于修复至关重要。实验基于初步发现，表明完整胃中有效的胃修复需要磷脂酶 C 和蛋白激酶 C。我们的第三个目标是评估执行胃修复工作的 Ca2+ 依赖性信号传导的下游靶点。我们将评估 NHE2 Na/H 交换器的作用，该交换器被证明作为 TFF2 的下游效应器对于胃修复至关重要。我们还将评估肌动蛋白细胞骨架、紧密连接以及在修复过程中调节这些细胞结构的小 GTP 酶的 Ca2+ 依赖性调节。所有目标都集中在非甾体抗炎药抑制环氧合酶（COX）/前列腺素途径的作用，第一个和第三个目标还检查幽门螺杆菌感染引起的所研究途径的变化。这些结果将为了解胃发病机制的早期因素提供一个独特的窗口，这有可能导致新的目标和新的干预策略，从而最大限度地减少胃损伤并加速愈合。