Elucidating the mechanism behind TFF2-mediated gastric restitution

阐明 TFF2 介导的胃恢复背后的机制

• 批准号: 9396272
• 负责人: Kristen Engevik
• 金额: $ 4.07万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-16 至 2020-08-15
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9396272
• 关键词: Address; Affect; Agonist; Anti-Inflammatory Agents; Anti-inflammatory; Apical; CXCR4 Receptors; CXCR4 gene; Calcium; Calcium Signaling; Caring; Cell Line; Cell Survival; Cells; Cholangiocarcinoma; Chronic Kidney Failure; Cost of Illness; Data; Dementia; Development; Elderly; Epidermal Growth Factor Receptor; Epithelial; Epithelial Cells; Event; Exhibits; Extracellular Signal Regulated Kinases; G-Protein-Coupled Receptors; Gastric Tissue; Gastric mucosa; Gastric ulcer; Gastrointestinal tract structure; Goals; Healthcare; Healthcare Systems; Helicobacter Infections; Impaired wound healing; In Vitro; Incidence; Injury; Irritants; Knockout Mice; Laboratories; Lasers; Lead; Lesion; Link; MAPK3 gene; Mediating; Mediator of activation protein; Medical; Mucous Membrane; Mucous body substance; Mus; NHE2; Organoids; Outcome; Ovarian; Pathway interactions; Peptic Ulcer; Peptides; Pharmaceutical Preparations; Phosphorylation; Physiology; Play; Population; Process; Protein Inhibition; Protein Isoforms; Protein Kinase C; Proteins; Proton Pump Inhibitors; Receptor Signaling; Reporting; Research; Risk; Role; Signal Pathway; Signal Transduction; Site; Sodium-Hydrogen Antiporter; Stomach; Stress; System; Testing; Therapeutic; Tissues; Transgenic Mice; Treatment Protocols; Ulcer; United States; United States National Institutes of Health; Work; Wound Healing; base; bronchial epithelium; cell injury; cell motility; clinically relevant; experimental study; healing; immortalized cell; improved; in vivo; inhibitor/antagonist; innovation; new therapeutic target; novel; novel therapeutics; release of sequestered calcium ion into cytoplasm; repaired; response to injury; statistics; trefoil factor; two-photon; wound closure

PROJECT SUMMARY/ABSTRACT The gastric mucosa of the stomach is continually exposed to a variety of stress factors which can cause local epithelial damage, and potentially lead to larger mucosal lesions, known as peptic ulcers. Peptic ulcer disease (PUD) remains an important issue in healthcare as it occurs in 10-15% of the population and is common in the elderly. New research suggests that proton pump inhibitors (PPIs), the most widely used treatment regimens for PUD, may increase the risk of dementia and chronic kidney disease. As PUD is prevalent in the elderly, the increased risk of dementia with the use of PPIs is alarming. These latest findings highlight the need for a better understanding of the mechanisms of gastric repair that may lead to new therapeutic treatments and help to minimize ulcer incidence or accelerate the repair process. Gastric restitution is the initial event during repair in which damaged cells are expelled away from the site of injury and neighboring viable cells act to cover the denuded mucosa without proliferation. One important factor that has been shown to affect gastric epithelial restitution is the mucus secreted peptide, trefoil factor 2 (TFF2). Work from our lab has shown that TFF2 is necessary for restitution in vivo and requires the sodium hydrogen exchanger isoform 2 (NHE2) for proper repair following damage. Outside of the gastrointestinal tract, evidence points to the potential of TFF2 acting through the TFF receptor CXCR4 which transactivates EGFR. EGFR is known to activate the Erk signaling pathway which has been implicated in NHE2 activation and restitution. Additionally, intracellular calcium (Ca2+) has been shown to be a necessary component within repair. While TFF is known to stimulate protein kinase C (PKC) and Ca2+ mobilization and Ca2+ is known to modulate repair, there is no direct evidence that Ca2+ mobilization is required for TFF2 mediated repair. Due to the complexities of in vivo work and the inconsistences of in vitro immortalized cell lines, the signaling cascade behind TFF2-mediated restitution has yet to be confirmed. Preliminary data have shown that damaged gastric organoids exhibit TFF2-dependent repair, showing key parallels to in vivo findings. This proposal seeks to utilize the novel in vitro gastric organoid system, which has been previously shown to recapitulate native tissue, in order to elucidate the mechanism behind TFF2-driven repair. Based upon preliminary data and previous studies, I hypothesize that TFF2 is the initiating factor which stimulates downstream signaling cascades to promote restitution following repair. To test this hypothesis, I will pursue two specific aims: (1) to determine the role of TFF2/CXCR4 driven EGFR signaling on NHE2 activation and gastric restitution; and (2) to identify the role of PKC signaling and intracellular Ca2+ in TFF2-driven repair. By examining EGFR- and Ca2+-mediated restitution, we have the potential to draw together two separate fields and bring together a number of findings that have previously existed in isolation. The data and experiments presented herein are the logical starting place to address ulcer healing for conditions such as PUD and may provide new therapeutic clinically relevant approaches.

项目总结/摘要 胃的胃粘膜持续地暴露于各种应激因素，这些应激因素可引起局部胃粘膜损伤。 上皮损伤，并可能导致更大的粘膜病变，称为消化性溃疡。消化性溃疡病 (PUD)它仍然是医疗保健中的一个重要问题，因为它发生在10-15%的人口中，并且在 老人新的研究表明，质子泵抑制剂（PPI），最广泛使用的治疗方案， 对于PUD，可能会增加痴呆症和慢性肾病的风险。由于PUD在老年人中普遍存在， 使用质子泵抑制剂会增加患痴呆症的风险，这令人担忧。这些最新的发现强调了更好的 了解胃修复的机制，可能会导致新的治疗方法，并有助于 最大限度地减少溃疡发生率或加速修复过程。胃的恢复是修复过程中的初始事件， 这些受损细胞被从损伤部位排出，而邻近的活细胞用于覆盖损伤部位， 黏膜裸露无增生。一个重要的因素是影响胃上皮细胞 恢复是粘液分泌肽，三叶因子2（TFF 2）。我们实验室的工作表明，TFF 2是 体内恢复所必需的，并需要钠氢交换器亚型2（NHE 2）进行适当的 损坏后修复。在胃肠道之外，证据表明TFF 2具有作用潜力 通过TFF受体CXCR 4反式激活EGFR。已知EGFR激活Erk信号传导 NHE 2的激活和恢复涉及的途径。此外，细胞内钙（Ca 2+） 已被证明是修复过程中的必要组成部分。虽然已知TFF刺激蛋白激酶C (PKC)和Ca 2+动员和Ca 2+已知调节修复，没有直接证据表明Ca 2 + TFF 2介导的修复需要动员。由于体内工作的复杂性和 由于体外永生化细胞系的不一致性，TFF 2介导的恢复背后的信号级联反应具有 还有待确认初步数据表明，受损的胃类器官表现出TFF 2依赖性 修复，显示与体内发现的关键相似之处。该提案旨在利用新的体外胃类器官 系统，这已被证明是重演天然组织，以阐明机制 TFF 2驱动的修复。根据初步数据和以前的研究，我假设TFF 2是 启动因子，其刺激下游信号级联以促进修复后的恢复。测试 基于这一假设，我将追求两个具体目标：（1）确定TFF 2/CXCR 4驱动的EGFR的作用 信号传导对NHE 2活化和胃恢复的作用;和（2）确定PKC信号传导的作用， 细胞内Ca 2+在TFF 2驱动的修复中的作用。通过检查EGFR和Ca 2+介导的恢复，我们得到了 有可能将两个不同的领域结合在一起，并将以前已经发现的一些结果结合在一起。 孤立存在。本文提供的数据和实验是解决溃疡的逻辑起点 治疗PUD等病症，并可能提供新的临床相关治疗方法。