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

基本信息

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
项目类别：
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&apos 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

项目摘要

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.

项目摘要 /摘要在2型糖尿病（T2D）中，在淀粉样蛋白酶多肽（IAPP）组成的淀粉样蛋白沉积物中被发现胰岛。 T2D胰岛也从β细胞中受损的胰岛素分泌受损，胰高血糖素分泌失调从α细胞，感染增加和脉管系统的改变。在多种潜在机制中连接淀粉样蛋白沉积和胰岛功能障碍，高级糖基化终产物（愤怒）的接收器为最近显示的结合IAPP低聚物并在体外介导β细胞的毒性，结果也得到了支持使用转基因啮齿动物模型。但是，体外细胞培养模型虽然有价值，但并不能完全复制复杂的环境，细胞间或生物体的暂时变化。此外，人类和啮齿动物功能，结构，细胞组成和基因表达的胰岛不同。那是为了充分理解人类疾病的发病机理，必须研究人类细胞和组织中的这些过程体内上下文。这种研究受到了无法获得和操纵相对的限制无法接近的人体组织以及由于缺乏体内模型来纵向研究它们。因此尚不清楚内源性分泌的IAPP低聚物在原代人β中作用于愤怒受体细胞，如果这种信号在α细胞中发生，并且特定细胞类型中的IAPP-RAGE信号传导对胰岛有什么影响功能。我假设IAPP低聚物诱导的β和α细胞上的愤怒受体激活人类胰岛功能和体外和体内健康。为了使用人类胰岛检验我的假设，我将采用四种新型技术和试剂。 1）我们最近报道的伪书方法将实现有效的通用在重新聚集成功能性细胞簇之前对特定胰岛细胞类型的操纵。 2）新的插入术成像技术将允许在移植的人伪符中对淀粉样蛋白形成的纵向监测进入小鼠眼前的小鼠。 3）将伪书移植到最近开发的胰高血糖敲除小鼠将允许在体内准确测量人胰高血糖素的分泌。 4）单个核RNA测序方法的应用将允许评估转录对移植伪符中的特定细胞类型。在AIM 1中，我将测试愤怒介导IAPP的假设人胰岛在体外和体内的低聚物诱导的β细胞功能障碍。在AIM 2中，我将检验以下假设 ⍺细胞中的IAPP-RAGE信号传导导致人类胰岛在体外和体内的分泌失调。这些目标的完成将阐明负责T2D发病机理的关键机制研究新的预防和治疗方法的途径。我将从杰出的我在范德比尔特糖尿病研究与培训中心的环境，协作和心态过渡到独立为身体科学家。