Pathophysiology of Diabetic Gastroparesis

糖尿病胃轻瘫的病理生理学

• 批准号: 10618295
• 负责人: GIANRICO FARRUGIA
• 金额: $ 55.41万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-15 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10618295
• 关键词: ATAC-seq; Address; Affect; Anti-Inflammatory Agents; Biological; Blood Cells; Cells; Complement; Complications of Diabetes Mellitus; Cytometry; Data; Development; Diabetes Mellitus; Diabetic mouse; Disease; Enhancers; Environment; Epigenetic Process; Equilibrium; Exposure to; Functional disorder; Gastric Emptying; Gastroparesis; Gene Expression; Genes; Genetic; Health; Immune; Infiltration; Inflammation Mediators; Inflammatory; Interstitial Cell of Cajal; Knowledge; Macrophage; Metabolism; Mononuclear; Mus; Obstruction; Oxidative Stress; Patients; Phagocytes; Phenotype; Play; Positioning Attribute; Prevention; Proteins; Role; Signal Pathway; Solid; Source; Stomach; System; Techniques; Technology; Testing; Tissues; Work; cell injury; cell type; cytokine; diabetic; diabetic gastroparesis; epigenomics; experimental study; gastrointestinal; improved; monocyte; paracrine; preservation; response; single-cell RNA sequencing; therapy development

PROJECT SUMMARY/ABSTRACT Diabetes mellitus is associated with multiple complications including diabetic gastroparesis. The systemic effects of diabetes modify all cells in the body but in common with other diabetic complications, gastroparesis does not develop in all patients. Delayed gastric emptying (GE) in the absence of obstruction defines gastroparesis and also occurs in some but not all diabetic mice. These observations suggest that together with genetics, convergence of systemic changes with local factors is necessary to develop delayed GE in diabetes. We previously have found that delayed GE that is associated with loss of interstitial cells of Cajal (ICC), which in turn is associated with fewer CD206+ muscularis propria macrophages (MPMs). MPMs play a central role in modifying the cellular content and biological environment of the GI muscularis propria in health and disease. The source of gastric MPMs and the mechanisms for activation of injurious molecules in MPMs by diabetes are not known. The overall hypothesis of this proposal is that the underlying central determinant of delayed gastric emptying in diabetes is the combination of a programmed activation response evoked in monocytes and the tissue environment of new monocyte-derived MPMs in the gastric muscularis propria. This will be tested in three specific aims (SA). SA1 will determine the effect of diabetes on circulating monocytes that primes them for infiltration and activation in gastric muscularis propria. SA2 will determine the origin of activated MPMs that populate the gastric muscularis propria following onset of diabetes and SA3 will determine how newly established and activated MPMs cause cellular injury in the diabetic stomach. The SAs are supported by extensive preliminary data. 1) We have found that systemic exposure to diabetes modifies the epigenomic landscape of circulating monocytes so that monocytes are poised to express a restricted complement of signaling pathways when they enter the tissue and become MPMs; 2) MPMs in the diabetic stomach are derived from infiltrating monocytes; 3) Diabetes results in the presence of new, distinct, discrete types of MPMs that are unique to the tissue; 4) Lineage-tagged, long-lived MPMs are not changed by diabetes; 5) Disruption of cellular metabolism in the gastric muscularis propria by diabetes activates monocyte-derived MPMs in close apposition to ICC to produce injurious cytokines, which cause damage to ICC and disrupted gastric function. To address the overall hypothesis we have developed techniques to isolate identified MPMs and monocytes, applied highly sophisticated technology for profiling genes by single cell RNASeq, ATAC-Seq, and proteins by mass cytometry (CyTOF), and determined changes in the epigenomic landscape in innate immune cells based on phenotypes identified in single cell studies. The preliminary data and the proposed experiments position us to identify the key steps that determine the responses to diabetes in innate immune cells that result in development of delayed GE. The new knowledge gained will be crucial to direct targeting of the mononuclear phagocyte system for prediction, prevention and treatment of diabetic gastroparesis.

项目概要/摘要 糖尿病与多种并发症相关，包括糖尿病性胃轻瘫。系统性的 糖尿病的影响会改变体内的所有细胞，但与其他糖尿病并发症相同的是胃轻瘫 并非所有患者都会出现。在没有梗阻的情况下胃排空延迟（GE）定义为 胃轻瘫也发生在一些但不是所有糖尿病小鼠中。这些观察表明，连同 从遗传学角度来看，全身变化与局部因素的融合对于糖尿病迟发性 GE 的发生是必要的。 我们之前发现延迟的 GE 与 Cajal 间质细胞 (ICC) 的丢失有关，这 反过来又与较少的 CD206+ 固有肌层巨噬细胞 (MPM) 相关。 MPM 在以下方面发挥着核心作用： 改变健康和疾病中胃肠道固有肌层的细胞内容和生物环境。 胃MPMs的来源以及糖尿病激活MPMs中有害分子的机制是 不知道。该提案的总体假设是延迟的根本核心决定因素 糖尿病的胃排空是由以下因素引起的程序化激活反应的组合： 单核细胞和胃肌层中新单核细胞衍生的 MPM 的组织环境 固有的。这将在三个特定目标（SA）中进行测试。 SA1 将确定糖尿病对循环的影响 单核细胞为它们在胃固有肌层中的渗透和激活做好准备。 SA2 将确定 糖尿病和 SA3 发病后胃固有肌层中活化的 MPM 的起源 确定新建立和激活的 MPM 如何导致糖尿病胃细胞损伤。 SA 得到了广泛的初步数据的支持。 1) 我们发现全身暴露于糖尿病会改变 循环单核细胞的表观基因组景观，以便单核细胞准备表达受限的 当信号通路进入组织并成为 MPM 时，它们是信号通路的补充； 2) 糖尿病患者的 MPM 胃源自浸润性单核细胞； 3) 糖尿病导致出现新的、独特的、离散的 组织特有的 MPM 类型； 4) 谱系标记的、长寿命的 MPM 不会因糖尿病而改变； 5) 糖尿病破坏胃固有肌层的细胞代谢，激活单核细胞来源的细胞 MPM 与 ICC 紧密相连，产生有害细胞因子，对 ICC 造成损害并破坏 胃功能。为了解决总体假设，我们开发了分离已识别 MPM 的技术 和单核细胞，应用高度复杂的技术通过单细胞 RNASeq、ATAC-Seq 进行基因分析， 通过质谱流式细胞仪 (CyTOF) 检测蛋白质和蛋白质，并确定先天性表观基因组景观的变化 基于单细胞研究中确定的表型的免疫细胞。初步数据和建议 实验使我们能够确定决定先天免疫对糖尿病反应的关键步骤 导致延迟性 GE 发生的细胞。获得的新知识对于直接瞄准目标至关重要 用于预测、预防和治疗糖尿病胃轻瘫的单核吞噬细胞系统。