Mechanotransduction in gastrointestinal physiology

胃肠生理学中的机械传导

• 批准号: 10443589
• 负责人: Arthur Beyder
• 金额: $ 35.78万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-17 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10443589
• 关键词: Affect; Afferent Neurons; Award; Bathing; Biosensor; Calcium; Calcium Channel; Cell Line; Cell physiology; Cells; Chronic; Chronic diarrhea; Constipation; Consumption; Data; Diagnosis; Dyspepsia; Electrophysiology (science); Enteral; Enteroendocrine Cell; Epithelial; Esthesia; Foundations; Gastrointestinal Diseases; Gastrointestinal Motility; Gastrointestinal Physiology; Gastrointestinal tract structure; Gene Expression Profile; Generations; Goals; Health; Healthcare; Human; Image; In Vitro; Intestines; Ion Channel; Irritable Bowel Syndrome; Knock-out; Knockout Mice; Knowledge; Laboratories; Lead; Light; Limb structure; Link; Mechanics; Methods; Molecular; Mus; Neuroepithelial; Organ; Organoids; Outcome; Pathway interactions; Patients; Physiological; Physiology; Piezo 2 ion channel; Population; Positioning Attribute; Regulation; Reporter; Role; Ryanodine Receptor Calcium Release Channel; Sensory; Serotonin; Signal Transduction; Signaling Molecule; Smooth Muscle; Symptoms; Testing; Tissues; Transgenic Mice; United States National Institutes of Health; Visceral; Work; afferent nerve; base; cell motility; cost estimate; experimental study; gastrointestinal; gastrointestinal epithelium; gastrointestinal function; glucagon-like peptide 1; in vivo; innovation; mechanical force; mechanotransduction; mouse model; new therapeutic target; novel; novel diagnostics; optogenetics; productivity loss; public health relevance; receptor; response; selective expression; sensor; voltage

PROJECT SUMMARY/ABSTRACT Functional gastrointestinal diseases (FGIDs), like irritable bowel syndrome, affect ~15% of the US population. Disruptions in the sensation of forces, also known as mechanosensation, are frequent in patients with FGIDs. Therefore, my laboratory’s long-term goal is to elucidate the cellular and molecular mechanisms of gastrointestinal (GI) mechanosensitivity in health and FGIDs. There are several mechanosensory pathways in the GI tract. One important mechanosensory pathway involved in FGIDs is neuro-epithelial, which is composed of a specialized sensory epithelial enteroendocrine cells (EECs) and intrinsic or extrinsic afferent neurons. We discovered a sub-population EECs which are mechanosensitive and express a mechanosensitive ion channel, Piezo2. In these mechanosensitive EECs, force-driven activation of Piezo2 channels is necessary for generation of “receptor currents” that lead to intracellular Ca2+ increases, the release of signaling molecules and downstream physiologic effects, like epithelial secretion. Thus, Piezo2 EECs appear to be important epithelial mechanosensors, but knowledge gaps limit our ability to target them. The overall objective of this proposal is to determine Piezo2 EECs roles in GI physiology by testing a novel hypothesis that mechanosensitive Piezo2 EECs use a Ca2+ signaling cascade to link Piezo2 activation with release of 5- HT and/or GLP-1 and thereby regulate GI motility and secretion. We will test the hypothesis in 3 Specific Aims. In Aim 1, we will determine the precise mechanotransduction mechanism that connects a very rapid Piezo2 receptor current with prolonged intracellular Ca2+ increase that is necessary for the release of signaling molecules. In Aim 2, we will determine Piezo2 EEC sub-populations based on GI region and the signaling molecules they contain and release. In Aim 3, we will determine how mechanosensitive Piezo2 EECs regulate mechanically induced GI secretion and contractions. We established novel transgenic mouse models that allow us to lineage track, stimulate, and interrogate specific EEC sub-populations. We will use these mouse models and validated EEC lines in a range of innovative and established approaches from single cells to in vivo to determine mechanosensitive EEC functions and their roles in GI physiology. The experiments are foundationally linked to previous work but represent a new and exciting direction and can we can complete in the defined award period. The results from these studies are poised to provide significant advances in the understanding of basic cellular and molecular mechanotransduction mechanisms, sensory epithelial function, GI mechanobiology, and have a broad translational value in physiology. A deep understanding of EEC mechanotransduction positions us well to determine alterations in mechanosensitive EECs in FGIDs, so that we may target them as novel and specific therapies.

项目总结/摘要 功能性胃肠道疾病（FGID），如肠易激综合征，影响约15%的美国人口。 力觉障碍，也称为机械感觉，在FGID患者中很常见。 因此，我的实验室的长期目标是阐明 胃肠道（GI）的机械敏感性在健康和FGID。有几个机械感觉通路， 胃肠道参与FGIDs的一个重要的机械感觉通路是神经上皮，其由以下组成： 一个专门的感觉上皮肠内分泌细胞（EECs）和内在或外在的传入神经元。我们 发现了机械敏感的并且表达机械敏感离子通道的亚群EECs， 压电2。在这些机械敏感的EEC中，力驱动的Piezo 2通道的激活是必要的， 产生“受体电流”，导致细胞内Ca 2+增加，释放信号分子 和下游生理效应，如上皮分泌。因此，Piezo 2 EEC似乎很重要， 上皮机械传感器，但知识的差距限制了我们的能力，以针对他们。本报告的总体目标 一项提案是通过测试一种新的假设来确定Piezo 2 EEC在GI生理学中的作用， 机械敏感性Piezo 2 EEC使用Ca 2+信号级联将Piezo 2激活与5-羟色胺的释放联系起来。 HT和/或GLP-1，从而调节GI运动和分泌。我们将在3个具体的测试假设 目标。在目标1中，我们将确定精确的机械转导机制，连接一个非常快速的 Piezo 2受体电流与延长的细胞内Ca 2+增加，这是释放信号所必需的 分子。在目标2中，我们将基于GI区域和信号传导来确定Piezo 2 EEC亚群。 它们所包含和释放的分子。在目标3中，我们将确定机械敏感的Piezo 2 EEC如何调节 机械诱导的GI分泌和收缩。我们建立了新的转基因小鼠模型， 我们的血统跟踪，刺激，并询问特定的EEC亚群。我们将使用这些小鼠模型 并在一系列创新和成熟的方法中验证EEC系，从单细胞到体内， 确定机械敏感的EEC功能及其在GI生理学中的作用。了实验 基本上与以前的工作，但代表了一个新的和令人兴奋的方向，我们可以完成在 确定的奖励期限。这些研究的结果有望在以下方面提供重大进展： 理解基本的细胞和分子机械转导机制，感觉上皮功能， GI机械生物学，并在生理学中具有广泛的转化价值。深入了解EEC 机械转导使我们能够很好地确定FGID中机械敏感性EEC的改变，因此， 我们可以把它们作为新的和特定的治疗方法。