Measurement and Molecular Mechanisms of Altered Esophageal Distensibility

项目摘要 调节食管疾病发病率的一个共同因素是食管的可扩张性改变， 壁，可能导致食物转运受损、阵发性窒息、食管滞留和误吸。在 这项提案将开发新的方法来量化疾病状态下的食管壁扩张性 其特征在于扩张性增加或降低，相应地，表型患者获得粘膜 活组织检查，并研究相应的分子机制。嗜酸性食管炎患者 (EoE)将使用功能性管腔成像探针（FLIP）研究硬皮病（SSc）和贲门失弛缓症 在标准护理（SOC）治疗前后（或治疗后）的地形图和四维阻抗测压（4D-IM） 在SSc的情况下结合SOC护理和Bravo pH测定）。我们的首要目标是了解 通过关键的机制研究导致食管腔扩张性改变的分子机制 炎症介质：核因子κ B激酶β亚单位（IKKβ）和信号转导抑制剂 和转录激活因子3（STAT 3）。这一建议的意义在于：1）扩大我们的 从神经肌肉功能的一维焦点理解食管疾病的发病机制 全面研究食管壁力学作为功能和功能障碍的决定因素;以及 2)上皮细胞IKKβ和上皮细胞STAT 3信号在多种生物学调节中的中心作用 过程，如炎症，免疫，细胞存活和细胞生长。项目负责人具有专业知识 食管病理生理学、转化研究、食管疾病动物模型、细胞信号传导 和上皮细胞生物学。在这里，我们将测试的假设，改变食管扩张性是介导的， 通过食管粘膜中的IKKβ的不同激活， 贲门失弛缓症的EoE或异常管腔加压以及STAT 3信号促进食管平滑肌 SSc肌肉萎缩。为了探索这些过程，我们将采取三个相互关联的具体目标。在 目的1：我们将研究上皮IKKβ/NFκB和STAT 3信号通路作为食管癌改变的调节剂， 在使用FLIP表型分型的患者中使用粘膜活检测量EoE、SSc和贲门失弛缓症的管腔扩张性 地形和4D-IM以及在SSc的情况下的Bravo pH测定。在目标2中，我们将确定 上皮IKKβ信号转导促进EoE纤维化。在这里，我们将利用一种新的转基因小鼠模型， 用卵清蛋白处理食管上皮IKKβ缺失，并进行3D器官型培养。在目标3中， 将决定上皮细胞STAT 3信号在促进食管平滑肌细胞损失中的需要 在SSc食管疾病中。这将采用新的SSc（食管癌）转基因小鼠模型进行。 用博来霉素处理的上皮STAT 3缺失）。我们预计这些研究将确定导致 在这些疾病状态下，异常食管腔扩张性可能作为未来的治疗方法， 目标的

PROJECT SUMMARY A common element mediating the morbidity of esophageal disorders is altered distensibility of the esophageal wall, potentially resulting in impaired food transit, episodic choking, esophageal retention, and aspiration. In this proposal we will develop novel methodologies to quantify esophageal wall distensibility in disease states characterized by either increased or decreased distensibility, phenotype patients accordingly, obtain mucosal biopsies, and investigate the corresponding molecular mechanisms. Patients with eosinophilic esophagitis (EoE), scleroderma (SSc), and achalasia will be studied using functional luminal imaging probe (FLIP) topography and 4D impedance manometry (4D-IM) before and after standard of care (SOC) treatment (or in conjunction with SOC care and Bravo pH-metry in the case of SSc). Our overarching goal is to understand the molecular mechanisms leading to altered esophageal luminal distensibility through mechanistic studies of key mediators of inflammation: inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ) and signal transducer and activator of transcription 3 (STAT3). The significance of this proposal lies in: 1) expanding our understanding of esophageal disease pathogenesis from a one-dimensional focus on neuromuscular function to a comprehensive study of esophageal wall mechanics as the determinant of function and dysfunction; and 2) the central roles of epithelial IKKβ and epithelial STAT3 signaling in the regulation of diverse biological processes, such as inflammation, immunity, cell survival, and cell growth. The projects leaders have expertise in esophageal pathophysiology, translational research, animal models of esophageal disease, cell signaling, and epithelial cell biology. Here, we will test the hypothesis that altered esophageal distensibility is mediated through differential IKKβ activation in the esophageal mucosa triggered by either eosinophilic inflammation in EoE or abnormal luminal pressurization in achalasia and that STAT3 signaling promotes esophageal smooth muscle atrophy in SSc. To explore these processes, we will undertake three interrelated Specific Aims. In Aim 1, we will investigate epithelial IKKβ/NFκB and STAT3 signaling as modulators of altered esophageal luminal distensibility in EoE, SSc, and achalasia using mucosal biopsies in patients phenotyped using FLIP topography and 4D-IM as well as Bravo pH-metry in the case of SSc. In Aim 2, we will determine the role of epithelial IKKβ signaling in promoting fibrosis in EoE. Here, we will utilize a novel transgenic mouse model with esophageal epithelial IKKβ deletion treated with egg ovalbumin, and 3D organotypic culture. In Aim 3, we will determine the requirement for epithelial STAT3 signaling in promoting esophageal smooth muscle cell loss in SSc esophageal disease. This will be undertaken with a new transgenic mouse model of SSc (esophageal epithelial STAT3 deletion treated with bleomycin). We anticipate that these studies will identify factors leading to abnormal esophageal luminal distensibility in these disease states that may serve as future therapeutic targets.