Store-operated Orai3 calcium channels in metabolism and obesity

商店操纵的 Orai3 钙通道在代谢和肥胖中的作用

• 批准号: 10599319
• 负责人: Trayambak Pathak
• 金额: $ 10.45万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10599319
• 关键词: Address; Adipocytes; American; Area; Attenuated; Biological Process; Blood Pressure; Blood Vessels; Brain; Brown Fat; Calcium; Calcium Channel; Calcium Signaling; Calcium-Sensing Receptors; Cardiovascular Diseases; Cell Nucleus; Cell membrane; Cell physiology; Cells; Central Nervous System; Complex; Data; Deacetylation; Development; Diet; Disease; Dyslipidemias; Electron Microscopy; Epidemic; Fatty acid glycerol esters; Gene Expression; Generations; Genetic Transcription; Glucose tolerance test; Goals; Growth; Heart Diseases; Heart failure; High Fat Diet; Homeostasis; House mice; Hyperglycemia; Hypertension; Insulin Resistance; Knock-out; Knockout Mice; Knowledge; Label; Life; Lipolysis; Malignant Neoplasms; Mammals; Measures; Mediating; Medical; Membrane Potentials; Metabolic; Metabolic Diseases; Metabolism; Methods; Mitochondria; Modality; Molecular; Mus; Nerve; Neurons; Non-Insulin-Dependent Diabetes Mellitus; Norepinephrine; Obese Mice; Obesity; Obesity associated cardiovascular disease; Obesity associated disease; Organelles; Overweight; Oxidative Phosphorylation; Oxidoreductase; PPAR gamma; Pathology; Pathway interactions; Peripheral Nervous System; Persons; Phenotype; Physiological; Physiology; Play; Population; Predisposition; Protein Isoforms; Proteins; RNA; Rabies virus; Regulation; Research; Risk Factors; Role; Route; SLC17A8 gene; Second Messenger Systems; Signal Pathway; Signaling Molecule; Spinal; Structure; Sympathetic Ganglia; Telemetry; Testing; Thermogenesis; Tissues; Transgenic Mice; Vertebral column; Weight Gain; Work; cancer type; cardiometabolism; cell type; experimental study; heart function; insulin tolerance; lipid metabolism; mitochondrial metabolism; nerve supply; neuronal excitability; novel; obesity treatment; receptor coupling; spatiotemporal; transcription factor; uncoupling protein 1

Project Summary/Abstract This K99/R00 proposal aims to characterize novel molecular mechanisms of obesity and develop non-invasive methods for treating obesity and obesity-related cardiovascular diseases. The proposal addresses a fundamental gap in knowledge with a significant impact on the treatment of obesity. Obesity is a major contributor to several pathologies, including type 2 diabetes, cardiovascular disease, and cancer. In recent years, studies have shown that Ca2+ signals play a crucial role in lipid metabolism. Orai proteins (Orai1-3) are highly Ca2+ selective channels that contribute ubiquitous and evolutionary conserved routes of regulated Ca2+ entry into all cells and play a major role in a myriad of cellular and physiological functions, including lipolysis. Here, I propose to study the function of Ca2+ entry through Orai3, a mammalian specific Ca2+ selective Orai channel protein, in metabolism, neuronal innervation, neuronal activation, and its role in regulating thermogenesis and obesity. We have generated Orai3 whole-body knockout and Orai3flx/flx mice for tissue-specific knockouts. My preliminary data show that Orai3 knockout mice housed at 15-18°C and on regular diets quickly become obese, and their weight gain is derived from fat accumulation. This suggests that Orai3 plays an essential role in fat metabolism. These Orai3 KO mice also have reduced heat generation, reduced sympathetic innervation to brown adipose tissue (BAT), suggesting that adiposity is due to reduced BAT thermogenesis and/or altered innervation or activation of norepinephrine (NE) producing sympathetic neurons, which regulate BAT thermogenesis. In this application, I propose to address the above- described causes of adiposity in Orai3 KO mice with the following three aims and key experiments, 1) Ca2+ entry through Orai3 is crucial for BAT mitochondrial heat generation to control adiposity, which will be determined by measuring parameters of mitochondrial metabolism. 2) Orai3 activity is critical for Ca2+-dependent gene transcription of UCP1, required for BAT thermogenesis, which will be assessed by studying the transcription factors that regulate UCP1 expression and by rescuing UCP1 expression in Orai3 KO mice and determining cardio-metabolism on Orai3 KO and UCP1-rescued mice. 3) Orai3 is required in the central and peripheral nervous system (CNS and PNS) to regulate BAT activity, which will be determined by analyzing Orai3 levels in both CNS and PNS using RNA scope, deleting Orai3 in CNS and measuring BAT activity, and deleting Orai3 in CNS and measuring cold and high fat diet- induced hypertension and obesity. This study will help decipher the unique role of Orai3 in BAT and in both central and sympathetic neurons. It will bridge the gap between Ca2+ homeostasis and mitochondrial function and unveil a novel role for Orai3 Ca2+ signaling in lipid metabolism and obesity, establishing Orai3 as a target in obesity and obesity-related cardiovascular disease.

项目概要/摘要 该 K99/R00 提案旨在表征肥胖和肥胖的新分子机制 开发治疗肥胖和肥胖相关心血管疾病的非侵入性方法。这 提案解决了知识上的根本差距，对治疗产生重大影响 肥胖。肥胖是多种疾病的主要原因，包括 2 型糖尿病、心血管疾病 疾病和癌症。近年来研究表明Ca2+信号在血脂调节中发挥着至关重要的作用 代谢。 Orai 蛋白 (Orai1-3) 是高度 Ca2+ 选择性通道，有助于普遍存在和 受调节的 Ca2+ 进入所有细胞的进化保守途径，并在许多细胞中发挥重要作用 细胞和生理功能，包括脂肪分解。在这里，我建议研究一下Ca2+的功能 通过 Orai3（一种哺乳动物特异性 Ca2+ 选择性 Orai 通道蛋白）进入代谢、神经元 神经支配、神经元激活及其在调节产热和肥胖中的作用。我们有 生成了 Orai3 全身敲除小鼠和用于组织特异性敲除的 Orai3flx/flx 小鼠。我的初步 数据显示，Orai3 基因敲除小鼠在 15-18°C 的环境下饲养并定期饮食，很快就会变得肥胖， 他们的体重增加来自于脂肪的积累。这表明 Orai3 起着至关重要的作用 在脂肪代谢中。这些 Orai3 KO 小鼠还减少了产热、减少了交感神经 棕色脂肪组织 (BAT) 的神经支配，表明肥胖是由于 BAT 减少所致 生热作用和/或神经支配改变或去甲肾上腺素 (NE) 产生交感神经的激活 神经元，调节 BAT 生热作用。在此申请中，我建议解决上述问题 - 描述了 Orai3 KO 小鼠肥胖的原因，具有以下三个目标和关键实验，1) Ca2+ 通过 Orai3 进入对于 BAT 线粒体产热以控制肥胖至关重要，这 将通过测量线粒体代谢参数来确定。 2) Orai3 活性对于 BAT 生热作用所需的 UCP1 Ca2+ 依赖性基因转录，将对其进行评估 通过研究调节 UCP1 表达的转录因子并挽救 UCP1 表达 在 Orai3 KO 小鼠中进行实验，并测定 Orai3 KO 和 UCP1 拯救小鼠的心脏代谢。 3）奥莱3 中枢和周围神经系统（CNS 和 PNS）需要调节 BAT 活性， 将通过使用RNA范围分析CNS和PNS中的Orai3水平来确定，删除Orai3 CNS并测量BAT活性，并删除CNS中的Orai3并测量冷和高脂肪饮食- 诱发高血压和肥胖。这项研究将有助于破译 Orai3 在 BAT 和 中枢神经元和交感神经元。它将弥合 Ca2+ 稳态和 线粒体功能并揭示了 Orai3 Ca2+ 信号在脂质代谢和肥胖中的新作用， 将 Orai3 确定为肥胖和肥胖相关心血管疾病的靶标。