Modifiers of Proinsulin Influence T2D Susceptibility

胰岛素原调节剂影响 T2D 易感性

基本信息

批准号：
9351508
负责人：
PETER ARVAN
金额：
$ 100.88万
依托单位：
SANFORD BURNHAM PREBYS MEDICAL DISCOVERY INSTITUTE
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-09-12 至 2020-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9351508
关键词：
20 year old Address Adult Amino Acid Substitution Beta Cell Biochemistry Biogenesis Bioinformatics C57BL/6 Mouse Cell physiology Cellular biology Complement Defect Development Diabetes Mellitus Diet Disease Disease Progression Endoplasmic Reticulum Ensure Environmental Risk Factor Exhibits Failure Foundations Gene-Modified Genes Genetic Genetic Models Genetic Polymorphism Goals Grant Health High Fat Diet Human Individual Insulin Insulin Resistance Intervention Lead Mass Spectrum Analysis Measurement Measures Methods Minor Mission Modality Molecular Molecular Chaperones Molecular Conformation Monoclonal Antibody R24 Mus National Institute of Diabetes and Digestive and Kidney Diseases Nature Non obese Non-Insulin-Dependent Diabetes Mellitus Obesity Pathogenesis Pathogenicity Pathway interactions Patients Pattern Pharmacology Phenotype Population Predisposition Process Production Prognostic Marker Proinsulin Proteins Proteome Proteomics Reporting Research Personnel Resistance development Specificity Testing Therapeutic Intervention Time Wolcott-Rallison syndrome Work biological adaptation to stress diabetic disulfide bond endoplasmic reticulum stress genetic approach genome wide association study improved insight insulin secretion islet mouse model non-diabetic novel novel diagnostics novel marker novel strategies novel therapeutics pressure proteostasis small molecule trafficking

项目摘要

PROJECT SUMMARY Type 2 diabetes (T2D) is caused by a failure of beta cells to produce sufficient insulin to maintain euglycemia. As a consequence of genetic/environmental factors, insulin resistance develops that pressures beta cells to increase insulin production. Although beta cells have some capacity to compensate for the demand, by approximately one-third of ~600 million individuals with obesity in the world develop go on to develop diabetes. The factors that lead to beta cell failure are unknown. Due to the polygenic nature of the disease, it is likely many genes modify beta cell function, and polymorphisms in any single gene would not be detected because they present minor contributions. Our underlying hypothesis is that multiple genes impact the efficiency of proinsulin folding in the endoplasmic reticulum (ER) and modify the progression of T2D. Significantly, our preliminary studies show that a high fat diet is sufficient to cause proinsulin misfolding well before diabetes development in C57BL/6 mice. In addition, we have identified genetic modifiers that exacerbate proinsulin misfolding and beta cell failure. We hypothesize that the fundamental cause of beta cell failure in T2D is a breakdown at the level of the ER with failure to efficiently fold excessive amounts of proinsulin and resulting consequences on downstream processing and secretion. To test our hypothesis, we have established a team of outstanding investigators to work together to identify critical proteins that modify proinsulin folding using state-of-the-art proteomics, biochemistry, cell biology, murine genetics and bioinformatics. In preliminary studies we developed methods to differentiate between specific disulfide bond defects and other misfolded conformations of proinsulin, generated all of the necessary murine strains and validated the proteomic mass spectrometry approach for proinsulin interactions using human islets. We have also demonstrated the potential of small molecules to improve proinsulin production in challenged islets. We expect our novel approach will identify distinct defects in the proinsulin folding pathway that represent the earliest changes leading to beta cell demise in both murine models and humans. The three aims of our R24 grant focus on defining how proinsulin folding patterns change when islets are challenged, and to identify how protein interactions with proinsulin may predict the efficiency of proinsulin trafficking through the secretory pathway, impacting islet health. Aim 1 will quantify the folded and unfolded state of proinsulin by measuring intermediates in the folding process in normal and diseased islets from well-characterized murine models. Aim 2 will define how the proteins that interact with proinsulin change during progression from normal, obese non-diabetic to T2D islets from human donors. Aim 3 will elucidate what interventions and chaperone functions may preserve productive proinsulin folding and restore an efficient proinsulin “proteostasis” network. Collectively, our proposed studies may identify novel biomarkers and avenues for therapeutic intervention in T2D, and therefore are of paramount importance to the mission of NIDDK.

项目摘要 2型糖尿病（T2D）是由β细胞未能产生足够的胰岛素来维持饮食症引起的。由于遗传/环境因素，胰岛素抵抗会发展出β细胞的压力尽管Beta细胞具有补偿需求的能力，但在世界肥胖症中约有6亿人中，大约有三分之一的人患有糖尿病。导致β细胞衰竭的因素尚不清楚。由于疾病的多基因性质，很可能许多基因修改了β细胞功能，并且不会检测到任何单个基因的多态性，因为他们提出了较小的贡献。我们的基本假设是多个基因影响内质网中（ER）中的促硫蛋白折叠并修改T2D的进展。重要的是，我们的初步研究表明，高脂肪饮食足以在糖尿病前引起促硫素折叠率不足 C57BL/6小鼠的发育。此外，我们已经确定了加剧促硫酸盐蛋白的遗传修饰剂错误折叠和β细胞衰竭。我们假设T2D中β细胞衰竭的基本原因是在ER的水平上分解，无法有效折叠超过蛋白素的数量和结果下游处理和分泌的后果。为了检验我们的假设，我们建立了一个团队杰出的研究人员共同努力，以识别使用使用的关键蛋白最先进的蛋白质组学，生物化学，细胞生物学，鼠遗传学和生物信息学。在初步我们开发了区分特定二硫键缺陷和其他错误折叠的方法蛋白素的构象产生了所有必要的鼠菌株并验证了蛋白质组学质量使用人类胰岛进行促硫蛋白相互作用的光谱法。我们还证明了潜力小分子以改善挑战胰岛中的促硫素的产生。我们希望我们的新颖方法将确定在Proinsulin折叠途径中的不同缺陷，该缺陷代表导致Beta细胞的最早变化在鼠模型和人类中都灭亡。我们R24赠款的三个目标重点是定义促硫素当胰岛受到挑战时，折叠模式会发生变化，并确定蛋白质与蛋白的相互作用如何通过秘密途径来预测促胰岛素的效率，从而影响胰岛健康。目标1意志通过在正常的折叠过程中测量中间体来量化折叠和展开的蛋白蛋白的状态以及来自特征良好的鼠模型的患病胰岛。 AIM 2将定义与之相互作用的蛋白质从正常，肥胖的非糖尿病到人类捐助者的T2D小岛的过程中，促生蛋白会变化。目标3 会阐明哪些干预措施和伴侣功能可以保留产品proinsulin折叠和恢复有效的Proinsulin“ Proteostasis”网络。总体而言，我们提出的研究可能会确定新颖在T2D中进行治疗干预的生物标志物和途径，因此对 Niddk的任务。