Role of RAGE in amyloid-induced pancreatic islet dysfunction in diabetes

RAGE 在淀粉样蛋白诱导的糖尿病胰岛功能障碍中的作用

• 批准号: 10506592
• 负责人: Jordan James Wright
• 金额: $ 15.99万
• 依托单位: VANDERBILT UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10506592
• 关键词: Affect; Alpha Cell; Alzheimer' s Disease; Amyloid; Amyloid deposition; Apoptosis; Behavior; Beta Cell; Binding; Bioinformatics; Biology; Blood Vessels; Cell Culture Techniques; Cell physiology; Cells; Cellular biology; Cessation of life; Collaborations; Complex; Data Science; Deposition; Developmental Biology; Diabetes Mellitus; Disease; Environment; Etiology; Functional disorder; Gene Expression; Gene Expression Profile; Genetic Transcription; Glucagon; Health; Human; Hyperglycemia; Imaging Techniques; Immunoglobulins; Immunology; Impairment; In Vitro; Individual; Inflammation; Inflammatory; Insulin; Insulin Resistance; International; Islet Cell; Islets of Langerhans; Knockout Mice; Link; Measurement; Measures; Mediating; Membrane; Mentors; Mentorship; Methods; Modeling; Molecular; Monitor; Mus; National Institute of Diabetes and Digestive and Kidney Diseases; Non-Insulin-Dependent Diabetes Mellitus; Nuclear; Nuclear RNA; Organism; Oxidative Stress; Pathogenesis; Pattern recognition receptor; Persons; Physicians; Physiology; Preventive; Process; Reagent; Receptor Activation; Reporting; Research Training; Rodent; Rodent Model; Role; Scientist; Signal Pathway; Signal Transduction; Structure; Techniques; Testing; Therapeutic; Time; Tissues; Toxic effect; Training; Transgenic Mice; Transgenic Organisms; Transplantation; United States; Viral; amylin receptor; amyloid formation; anterior chamber; cell type; collaborative environment; endoplasmic reticulum stress; eye chamber; genetic manipulation; human disease; human tissue; in vivo; in vivo Model; innovation; insulin secretion; intravital imaging; islet; islet amyloid polypeptide; knock-down; member; novel; novel strategies; pancreatic juice; prevent; receptor binding; receptor for advanced glycation endproducts; small hairpin RNA; transcriptome sequencing; transcriptomics

PROJECT SUMMARY / ABSTRACT In type 2 diabetes (T2D), amyloid deposits composed of islet amyloid polypeptide (IAPP) are found within pancreatic islets. T2D islets also have impaired insulin secretion from β cells, dysregulated glucagon secretion from α cells, increased inflammation, and alterations in vasculature. Among multiple potential mechanisms linking amyloid deposition and islet dysfunction, the receptor for advanced glycation endproducts (RAGE) was recently shown to bind IAPP oligomers and mediate β cell toxicity in vitro, which results were also supported using a transgenic rodent model. But in vitro cell culture models, while valuable, do not fully replicate the complex environmental, intercellular, or temporal changes in living organisms. Furthermore, human and rodent islets differ in function, structure, cellular composition, and gene expression. Thus, to fully understand the pathogenesis of human disease, one must study these processes in human cells and tissues in the in vivo context. Such studies have been limited by the inability to obtain and manipulate these relatively inaccessible human tissues and by the lack of in vivo models in which to study them longitudinally. It therefore remains unknown if endogenously secreted IAPP oligomers act on the RAGE receptor in primary human β cells, if such signaling occurs in α cells, and what effect IAPP-RAGE signaling in specific cell types has on islet function. I hypothesize that IAPP oligomer-induced activation of RAGE receptors on β and α cells impairs human islet function and health in vitro and in vivo. To test my hypothesis using human islets, I will employ four novel techniques and reagents. 1) Our recently reported pseudoislet method will enable efficient genetic manipulation of specific islet cell types prior to reaggregation into functional cell clusters. 2) New intravital imaging techniques will allow longitudinal monitoring of amyloid formation in human pseudoislets transplanted into the mouse anterior chamber of the eye. 3) Transplantation of pseudoislets into a recently developed glucagon knockout mouse will permit accurate measurement of human glucagon secretion in vivo. 4) Application of single nuclear RNA sequencing approaches will permit assessment of transcriptional effects on specific cell types in transplanted pseudoislets. In Aim 1, I will test the hypothesis that RAGE mediates IAPP oligomer-induced β cell dysfunction in human islets in vitro and in vivo. In Aim 2, I will test the hypothesis that IAPP-RAGE signaling in ⍺ cells causes dysregulated glucagon secretion in human islets in vitro and in vivo. Completion of these aims will elucidate key mechanisms responsible for pathogenesis of T2D, opening avenues for study into new preventive and therapeutic approaches. I will benefit from the outstanding environment, collaboration, and mentorship at the Vanderbilt Diabetes Research and Training Center as I transition to independence as a physician-scientist.

项目概要/摘要 在 2 型糖尿病 (T2D) 中，由胰岛淀粉样多肽 (IAPP) 组成的淀粉样蛋白沉积物存在于体内 胰岛。 T2D 胰岛的 β 细胞胰岛素分泌也受损，胰高血糖素分泌失调 来自α细胞、炎症增加和脉管系统的改变。在多种潜在机制中 将淀粉样蛋白沉积和胰岛功能障碍联系起来，晚期糖基化终末产物（RAGE）的受体是 最近显示可结合 IAPP 寡聚物并在体外介导 β 细胞毒性，该结果也得到支持 使用转基因啮齿动物模型。但体外细胞培养模型虽然有价值，但并不能完全复制 生物体中复杂的环境、细胞间或时间变化。此外，人类和啮齿动物 胰岛在功能、结构、细胞组成和基因表达方面有所不同。因此，要充分了解 人类疾病的发病机制，必须研究人体细胞和组织的这些过程。 体内环境。此类研究因无法获得和操纵这些相对 难以接近的人体组织以及缺乏对其进行纵向研究的体内模型。因此它 目前尚不清楚内源性分泌的 IAPP 寡聚体是否作用于原代人 β 中的 RAGE 受体 细胞，如果这种信号传导发生在 α 细胞中，以及特定细胞类型中的 IAPP-RAGE 信号传导对胰岛有何影响 功能。我推测 IAPP 寡聚体诱导的 β 和 α 细胞上 RAGE 受体的激活会损害 人体胰岛的体外和体内功能和健康。为了使用人类胰岛检验我的假设，我将采用 四项新技术和试剂。 1) 我们最近报道的伪胰岛方法将实现高效的遗传 在重新聚集成功能性细胞簇之前对特定胰岛细胞类型进行操作。 2) 新生命内 成像技术将允许纵向监测移植的人伪胰岛中淀粉样蛋白的形成 进入小鼠眼前房。 3）将伪胰岛移植到最近开发的 胰高血糖素基因敲除小鼠将能够准确测量体内人胰高血糖素分泌。 4） 单核RNA测序方法的应用将允许评估转录效应 移植的伪胰岛中的特定细胞类型。在目标 1 中，我将检验 RAGE 介导 IAPP 的假设 寡聚物诱导的体外和体内人类胰岛β细胞功能障碍。在目标 2 中，我将检验以下假设： ⍺ 细胞中的 IAPP-RAGE 信号传导导致体外和体内人胰岛胰高血糖素分泌失调。 这些目标的完成将阐明 T2D 发病机制的关键机制，开启 研究新的预防和治疗方法的途径。我将受益于优秀 我在范德比尔特糖尿病研究和培训中心的环境、协作和指导 作为一名医师科学家过渡到独立。