Identification and activation mechanisms of vagal and spinal nociceptors in esophageal mucosa

食管粘膜迷走神经和脊髓伤害感受器的识别和激活机制

• 批准号: 9978776
• 负责人: Thomas Edward Taylor-Clark
• 金额: $ 35.24万
• 依托单位: UNIVERSITY OF SOUTH FLORIDA
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-25 至 2023-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9978776
• 关键词: ASIC channel; Acids; Address; Anatomy; Animal Model; Animals; Bile Acids; C Fiber; Cations; Cavia; Chest Pain; Clinical; Data; Development; Electrophysiology (science); Embryo; Esophageal mucous membrane; Esophagus; Esthesia; Failure; Family; Fiber; Functional disorder; Future; GPBAR1 gene; Gastric Acid; Gastroesophageal reflux disease; Gene Expression Profiling; Gene Silencing; Genes; Genetic; Green Fluorescent Proteins; Health; Heartburn; Human; Investigation; Knowledge; Lead; Location; Mediating; Medical; Methods; Molecular; Mucous Membrane; Nerve; Nerve Fibers; Neural Crest; Neurons; Neurotransmitters; Nociception; Nociceptors; Organ Donor; Pain; Paper; Patients; Pharmaceutical Preparations; Pharmacology; Population; Positioning Attribute; Potassium; Process; Proton Pump Inhibitors; Protons; Publishing; Reflex action; Reflux; Refractory; Spinal; Stomach Content; Symptoms; TRPV1 gene; Target Populations; Therapeutic; Tissues; United States; afferent nerve; base; differential expression; experience; in vivo; knock-down; multiphoton imaging; neuroregulation; novel; pain sensation; patch clamp; patient population; persistent symptom; receptor; response; small hairpin RNA; targeted treatment; transgene expression

Project Summary Gastroesophageal reflux disease (GERD) is a major health problem in the United States, impacting over 20% of the population. In at least a quarter of these patients, symptoms caused by GERD such as heartburn and chest pain cannot be controlled by gastric acid suppression with proton pumps inhibitors (PPIs). This population of patients with PPI-refractory GERD have no effective medical treatment options. Failure to understand mechanisms of persistent symptoms in this condition is a major knowledge gap, and limits clinical therapeutic options. One potential cause of persistent symptoms in PPI-refractory GERD patients is weakly acidic (pH>5.0) reflux. This can cause activation of pain- mediating nerves (C-fiber nociceptors) in esophageal mucosa, but the molecular mechanisms have not been clearly elucidated. Furthermore it is not clear whether bile acid also directly activates esophageal C-fibers and mediates nociceptive symptoms in GERD. Our overall hypothesis is that the refluxates in PPI-refractory GERD (mild acid and bile acids) activate esophageal nociceptive C-fiber subtypes and contribute to persistent symptoms in refractory GERD. Determining the identity of the afferent nerve subtype(s) and the key receptor(s) responsible for PPI refractory symptoms are crucial for development of specific targets for this population. Over the past decade, we have identified 3 types of C-fibers in the esophagus which express differential receptors and neurotransmitters and have different central projections. Intriguingly, we have developed new data which demonstrated that two factors in weakly acidic refluxate robustly stimulate esophageal C-fibers: 1) bile acids (that are quite often found in the refluxates on PPI therapy), and 2) acid in low proton concentrations (pH=6.0, termed here mild acid). Our published papers and preliminary data suggest that the key receptors TGR5 and TASK1/ASIC3 are likely involved. Based on these progresses, we will first determine in aim 1 the subtypes of nociceptive afferent nerve terminals in esophagus mucosa which are more vulnerable to refluxates. We will then elucidate receptors mediating C-fiber activation by mild acid in aim 2. We will address the hypothesis that mild acid activates C-fiber subtypes via combination of inhibition of potassium two-pore domain (K2P) family channel (TASK1) and activation of cationic channels from the ASIC family (ASIC3). In aim 3, we will elucidate receptors mediating C-fiber activation by bile acids. We hypothesize that bile acids activate C- fiber subtype(s), which is mediated by the bile acid receptor TGR5. We will apply the approaches of gene expression analysis, patch clamp recordings, and recordings of nerve activity originating in the C-fiber nerve terminals. Studies will be carried out in in animal models in which neuron-selective gene knockdown by our validated in vivo shRNA silencing strategy. Elucidation of the mechanisms by which bile acids and mild acid activate C-fibers will help to develop novel targets for PPI--refractory GERD.

项目概要 胃食管反流病 (GERD) 是美国的一个主要健康问题，影响超过 占人口的20%。这些患者中至少有四分之一出现由 GERD 引起的症状，例如 胃灼热和胸痛不能通过质子泵抑制剂抑制胃酸来控制 （生产者价格指数）。这部分 PPI 难治性 GERD 患者没有有效的药物治疗 选项。未能理解这种情况下持续症状的机制是一个主要问题 知识差距，并限制了临床治疗选择。持续症状的一个潜在原因 PPI难治性GERD患者呈弱酸性（pH>5.0）反流。这可能会导致疼痛的激活 食管粘膜中的介导神经（C纤维伤害感受器），但分子机制尚未可知 已得到明确阐明。此外，尚不清楚胆汁酸是否也直接激活食管。 C 纤维并介导 GERD 中的伤害性症状。我们的总体假设是回流 PPI 难治性 GERD（弱酸和胆汁酸）激活食管伤害性 C 纤维亚型， 导致难治性 GERD 的持续症状。确定传入神经的身份 导致 PPI 难治性症状的亚型和关键受体对于发育至关重要 针对这一人群的具体目标。在过去的十年中，我们在工业领域中发现了 3 种类型的 C 纤维 食管表达不同的受体和神经递质，并具有不同的中枢 预测。有趣的是，我们开发的新数据表明，有两个因素对 酸性反流物强烈刺激食管 C 纤维：1）胆汁酸（通常存在于食管中） PPI 治疗时回流），以及 2）低质子浓度的酸（pH=6.0，此处称为弱酸）。我们的 已发表的论文和初步数据表明关键受体 TGR5 和 TASK1/ASIC3 很可能 涉及。基于这些进展，我们将首先在目标 1 中确定伤害性传入的亚型 食管粘膜的神经末梢更容易受到反流的影响。然后我们将阐明 目标 2 中弱酸介导 C 纤维激活的受体。我们将提出弱酸的假设 通过结合抑制钾双孔结构域 (K2P) 家族激活 C 纤维亚型 通道 (TASK1) 和 ASIC 系列阳离子通道的激活 (ASIC3)。在目标 3 中，我们将 阐明胆汁酸介导 C 纤维激活的受体。我们假设胆汁酸激活 C- 纤维亚型，由胆汁酸受体 TGR5 介导。我们将应用基因的方法 表达分析、膜片钳记录以及源自 C 纤维的神经活动记录 神经末梢。研究将在动物模型中进行，其中神经元选择性基因 通过我们经过验证的体内 shRNA 沉默策略进行敲低。阐明其机制 胆汁酸和弱酸激活 C 纤维将有助于开发 PPI（难治性 GERD）的新靶标。

项目成果

Acidic Pharyngeal Reflux Does Not Correlate with Symptoms and Laryngeal Injury Attributed to Laryngopharyngeal Reflux.

酸性咽部反流与症状和喉损伤无关。

• DOI: 10.1007/s10620-018-5372-1
• 发表时间: 2019-05
• 期刊: DIGESTIVE DISEASES AND SCIENCES
• 影响因子: 3.1
• 作者: Duricek, Martin;Banovcin, Peter;Halickova, Tatiana;Hyrdel, Rudolf;Kollarik, Marian
• 通讯作者: Kollarik, Marian

Comprehensive analysis of acidic pharyngeal reflux before and after proton pump inhibitor treatment in patients with suspected laryngopharyngeal reflux.

质子泵抑制剂治疗前后对可疑喉咽反流的患者进行酸性咽部反流的全面分析。

• DOI: 10.1097/meg.0000000000001584
• 发表时间: 2020-02
• 期刊: EUROPEAN JOURNAL OF GASTROENTEROLOGY & HEPATOLOGY
• 影响因子: 2.1
• 作者: Duricek, Martin;Banovcin, Peter, Jr.;Halickova, Tatiana;Hyrdel, Rudolf;Kollarik, Marian
• 通讯作者: Kollarik, Marian

Structure of vagal afferent nerve terminal fibers in the mouse trachea.

• DOI: 10.1016/j.resp.2018.01.001
• 发表时间: 2018-03
• 期刊: Respiratory physiology & neurobiology
• 影响因子: 2.3
• 作者: Hennel M;Harsanyiova J;Ru F;Zatko T;Brozmanova M;Trancikova A;Tatar M;Kollarik M
• 通讯作者: Kollarik M

Mapping of the Sensory Innervation of the Mouse Lung by Specific Vagal and Dorsal Root Ganglion Neuronal Subsets.

通过特定迷走神经和背根神经节神经元亚群绘制小鼠肺的感觉神经支配图。

• DOI: 10.1523/eneuro.0026-22.2022
• 发表时间: 2022
• 期刊: eNeuro
• 影响因子: 3.4
• 作者: Kim,Seol-Hee;Patil,MayurJ;Hadley,StephenH;Bahia,ParmvirK;Butler,ShaneG;Madaram,Meghana;Taylor-Clark,ThomasE
• 通讯作者: Taylor-Clark,ThomasE

Vagus Nerves Provide a Robust Afferent Innervation of the Mucosa Throughout the Body of the Esophagus in the Mouse.

• DOI: 10.1007/s00455-019-10051-8
• 发表时间: 2020-06
• 期刊: Dysphagia
• 影响因子: 2.6