Cytosolic and Plasma Membrane Circuitry of Beta Cell Redox Control: Role in Survival, Oxidative Defense and Insulin Secretion

β 细胞氧化还原控制的胞浆和质膜电路：在生存、氧化防御和胰岛素分泌中的作用

• 批准号: 9285794
• 负责人: JAVIER CUEVAS
• 金额: $ 32.52万
• 依托单位: UNIVERSITY OF SOUTH FLORIDA
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-19 至 2020-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9285794
• 关键词: Address; Adenovirus Vector; Affect; Antioxidants; Beta Cell; Biological; Cell Survival; Cell membrane; Cell physiology; Cells; Cellular Metabolic Process; Custom; Data; Defect; Diet; Electron Transport; Ensure; Enzymes; Exposure to; Generations; Glucose; Goals; Health; Hydrogen Peroxide; Islets of Langerhans; Knock-out; Knockout Mice; Lead; Link; Mediating; Metabolic Pathway; Metabolic stress; Metabolism; Mitochondria; Molecular; NAD+ kinase; NADH; NADP; NQO1 gene; Niacinamide; Non-Insulin-Dependent Diabetes Mellitus; Normal Cell; Oxidants; Oxidation-Reduction; Oxidative Stress; Oxides; Oxidoreductase; Oxygen; Pancreas; Pathway interactions; Physiological; Plants; Play; Process; Production; Publishing; Quinones; Regulation; Respiration; Rodent; Role; Second Messenger Systems; Secretory Cell; Signal Transduction; Structure of beta Cell of islet; System; TXN gene; Testing; Ubiquinone; analog; antioxidant enzyme; blood glucose regulation; design; environmental chemical; extracellular; glutaredoxin; imaging platform; insight; insulin secretion; islet; knock-down; member; novel; novel therapeutic intervention; overexpression; pancreatic juice; public health relevance; reactive oxygen intermediate; response; small hairpin RNA; therapeutic development

DESCRIPTION (provided by applicant): We have identified a novel cytosolic-plasma membrane circuit of redox control, dependent on plasma membrane oxidoreductase NQO1 and the cytosolic NADPH-regulating enzyme NAD kinase, which regulates NAD(P)H/NADP+ ratio, level of reactive oxygen intermediates (ROI) and glucose-stimulated insulin secretion (GSIS) from pancreatic beta cells. Our Preliminary Data demonstrate the critical role of these pathways for beta cell function, survival, and GSIS. Furthermore, NQO1 participates in the glucose-dependent process of quinone redox cycling, which regulates cytosolic NADH/NAD+ ratio and enhances GSIS. NAD kinase, a novel NADPH- regulating enzyme, is responsible for the de novo production of NADPH and participates in the protection of beta cells from oxidative stress. NQO1 and NAD kinase are critical for normal cell function, and have not been characterized in pancreatic beta cells. We will employ over- expression or knockdown using shRNA and adenoviral vectors strategies as well as NQO1 knockout pancreatic islets to analyze the role of these components in beta cell intermediary metabolism. We will analyze the role of NQO1 and NAD kinase on the response of beta cells or islets to glucose or other stimulatory agents using a custom-made integrated electrochemical- confocal imaging platform to simultaneously study islet metabolism, respiration, and signaling. These studies will provide greater insight into the mechanism of redox signaling in regulating insulin secretion and identify novel targets for the development of therapeutics for type 2 diabetes.

描述（由申请人提供）：我们已经确定了一种新的细胞溶质-质膜氧化还原控制回路，依赖于质膜氧化还原酶NQO 1和细胞溶质NADPH调节酶NAD激酶，其调节NAD（P）H/NADP+比率、活性氧中间体（ROI）水平和胰腺β细胞葡萄糖刺激的胰岛素分泌（GSIS）。我们的初步数据证明了这些通路对β细胞功能，存活和GSIS的关键作用。此外，NQO 1参与葡萄糖依赖的醌氧化还原循环过程，调节胞质NADH/NAD+比率并增强GSIS。NAD激酶是一种新的NADPH调节酶，负责NADPH的从头产生并参与保护β细胞免受氧化应激。NQO 1和NAD激酶对于正常细胞功能至关重要，并且尚未在胰腺β细胞中表征。我们将采用使用shRNA和腺病毒载体策略以及NQO 1敲除胰岛的过表达或敲减来分析这些组分在β细胞中间代谢中的作用。我们将分析NQO 1和NAD激酶对β细胞或胰岛对葡萄糖或其他刺激剂的反应的作用，使用定制的集成电化学共聚焦成像平台同时研究胰岛代谢，呼吸和信号传导。这些研究将为氧化还原信号在调节胰岛素分泌中的机制提供更深入的了解，并为2型糖尿病治疗药物的开发确定新的靶点。