Role of 12-lipoxygenase and 12-HETE signaling in beta-cell dysfunction

12-脂氧合酶和 12-HETE 信号在 β 细胞功能障碍中的作用

基本信息

批准号：
10583551
负责人：
ROHIT N. KULKARNI
金额：
$ 65.5万
依托单位：
UNIVERSITY OF CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-04-01 至 2025-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10583551
关键词：
Abdomen Acids Active Sites Adverse effects Affinity Applications Grants Arachidonate 12-Lipoxygenase Award Beta Cell Biology Cell Line Cell physiology Cells Cessation of life Characteristics Chemicals Collaborations Diabetes Mellitus Eicosanoids Enzymes Exhibits Family Functional disorder Funding G-Protein-Coupled Receptors GPR31 receptor Gene Deletion Genes Genetic Models Growth Factor Human Human Biology Image Imaging Device Inflammation Inflammation Mediators Inflammatory Insulin Insulin Resistance Intervention Knock-in Mouse Knock-out Knockout Mice Link Lipids Lipoxygenase Mediating Modeling Molecular Mus Obesity Oxidative Stress Paper Pathway interactions Phase Polyunsaturated Fatty Acids Productivity Protein Isoforms Publications Reagent Research Personnel Role Signal Transduction Small Business Technology Transfer Research System Testing Therapeutic Time Validation Work acid stress conditional knockout endoplasmic reticulum stress expectation humanized mouse impaired glucose tolerance in vivo in vivo Model inhibitor innovation insight insulin signaling intravital imaging islet mouse model novel pre-clinical receptor receptor-mediated signaling release of sequestered calcium ion into cytoplasm therapeutic target tool two-photon type I and type II diabetes virtual

项目摘要

Deficiencies in islet β-cell function and/or mass are central in the transition from impaired glucose tolerance to frank diabetes in the setting of both type 1 and type 2 diabetes. The lipoxygenases (LOXs) represent a family of enzymes that catalyzes the oxygenation of cellular poly-unsaturated fatty acids to form lipid inflammatory mediators in β-cells. The eicosanoid product of 12-LOX activity, 12-hydoxyeicosatetraenoic acid (12-HETE), imposes inflammatory and oxidative stress within β cells. A challenge in lipoxygenase biology, however, is that humans and mice express different isoforms of 12-LOX in β cells (encoded by ALOX12 and Alox15, respectively), with each isoform exhibiting different active-site characteristics. The strength of this application is the collaborative effort between Multi-PIs Drs. R. Mirmira (an expert in islet inflammation pathways) and R. Kulkarni (an expert in growth factor signaling in the islet), and coinvestigator J. Nadler (an expert in eicosanoid biology), who will collectively bring their expertise and unique reagents—including knockout and human gene knock-in mouse models that show human isoform activation, human 12-LOX-selective inhibitors, and primary human cells—to bear on the biology of 12-LOX and its inflammatory products. We hypothesize that during insulin resistance the activation of 12-LOX in β-cells promotes β cell dysfunction through receptor-mediated signaling by its downstream product 12-HETE. To test this hypothesis, we propose the following specific aims: Aim 1: Elucidate the molecular mechanisms linking β-cell insulin resistance to 12-LOX activity and cellular dysfunction. Aim 2: Determine the contribution of 12-LOX activity to β cell dysfunction in the setting of insulin resistance in vivo. Aim 3: Determine the role of the 12-HETE receptor GPR31 in mediating β-cell dysfunction downstream of 12-LOX. Until now, tools and reagents to interrogate the biology of human 12-LOX and 12-HETE did not exist. The primary impact of this proposal will be to set the stage for the expectations of therapeutically targeting the human 12-LOX pathway in insulin resistance/β-cell dysfunction, and to identify a potential new target in the 12-HETE G protein-coupled receptor GPR31.

在1型和2型糖尿病的情况下，胰岛β细胞功能和/或质量的缺陷是从葡萄糖耐受性受损到弗兰克糖尿病的核心。 Lipoxygyass（Loxs）代表了一种酶家族，该酶催化细胞多饱和脂肪酸的氧合，以在β细胞中形成脂质炎症介质。 12-lox活性，12-羟基羟基乙烯酸（12-HETE），β细胞内的炎症和氧化应激的eicosanoid产物。然而，脂氧合酶生物学的一个挑战是，人类和小鼠在β细胞中表达了12-LOX的不同同工型（分别由Alox12和Alox15编码），每个同工型都表现出不同的活性位点特征。该应用程序的优势是多PIS DRS之间的协作工作。 R. Mirmira（胰岛注射途径的专家）和R. Kulkarni（胰岛中生长因子信号的专家）和共同评估剂J. Nadler（eicosanaioid的专家）（eicosanaioid的专家）将集体带来他们的专业知识和独特的试验者 - 将人类的淘汰和人类类型的人类模型（包括人类的人类型）带入人类的模型，并构成人类的生物型，并构成人类的生物型，并构成了人类的生物型，并具有人类的生物形象，并具有人类的生物形象，该模型是构成人类的12-携带12-Lox及其炎症产品的生物学。我们假设在胰岛素抵抗期间，β细胞中12-LOX的激活通过其下游产物12-HETE通过受体介导的信号传导促进β细胞功能障碍。为了检验这一假设，我们提出了以下特定目的：目标1：阐明将β细胞胰岛素抵抗与12-LOX活性和细胞功能障碍联系起来的分子机制。 AIM 2：确定在体内胰岛素抵抗的情况下，12-LOX活性对β细胞功能障碍的贡献。 AIM 3：确定12-Hete受体GPR31在12-Lox下游介导β细胞功能障碍中的作用。到目前为止，还不存在询问人类12-lox和12-Hete生物学的工具和试剂。该提案的主要影响是为胰岛素抵抗/β细胞功能障碍中人类12-lox途径的期望奠定基础，并确定在12-HETE G蛋白偶联受体GPR31中的潜在新靶标。