Mechanisms of Human Insulin Resistance

人类胰岛素抵抗的机制

• 批准号: 8001364
• 负责人: W Timothy GARVEY
• 金额: $ 7.41万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-12-31 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8001364
• 关键词: 2,4-thiazolidinedione; Affect; Biogenesis; Body Composition; Body Weight; Body Weight decreased; Body fat; Carbohydrates; Cardiovascular Diseases; Complex; Coupling; Data; Defect; Diet; Exhibits; Fatty acid glycerol esters; Gene Expression; Generations; Genes; Glucose; Grant; Health Care Costs; Human; Indirect Calorimetry; Individual; Injury; Insulin; Insulin Resistance; Lipids; Mass Spectrum Analysis; Measures; Messenger RNA; Metabolic; Metabolic syndrome; Metabolism; Methods; Mitochondria; Mitochondrial Proteins; Modification; Molecular; Morphology; Muscle; Muscle Mitochondria; NADH dehydrogenase (ubiquinone); Non-Insulin-Dependent Diabetes Mellitus; Nonesterified Fatty Acids; Nuclear; Obesity; Pathogenesis; Patients; Physiology; Post-Translational Protein Processing; Production; Proteins; Proteome; Proteomics; Protons; Regulation; Research Design; Resistance; Resolution; Respiratory Chain; Skeletal Muscle; Spectrum Analysis; Staining method; Stains; Structure; Testing; Thiazolidinediones; Time; Tissue-Specific Gene Expression; Toxic effect; Two-Dimensional Gel Electrophoresis; Zucker Rats; base; cDNA Arrays; complex IV; density; feeding; gel electrophoresis; glucose uptake; insulin sensitivity; insulin sensitizing drugs; mRNA Expression; mitochondrial dysfunction; mitochondrial genome; oil red O; oxidation; protein complex; protein expression; research study; respiratory; respiratory protein

DESCRIPTION (provided by applicant): Insulin resistance is central to the pathogenesis of Type 2 diabetes (T2DM), the Metabolic Syndrome, and cardiovascular disease, and presents a heavy burden of patient suffering and health care costs. The immediate cause involves defective stimulation of glucose uptake into skeletal muscle. Insulin resistance is also associated with abnormalities in fat oxidation and accumulation of intramyocellular lipid (IMCL), although molecular mechanisms are unknown. Since mitochondria are responsible for lipid oxidation, it is tempting to explain increased IMCL on the basis of mitochondrial dysfunction, and there is recent evidence to support this idea. Over the past grant cycle, we have examined differential gene expression in human muscle using cDNA microarrays and found that multiple genes encoding mitochondrial proteins are down-regulated in insulin resistance. This data, together with the observation that insulin resistance involves selective depletion of complex IV proteins, have led us to a more detailed examination of the mitochondrial proteome and function in skeletal muscle. The current proposal combines human physiology and basic methods to test the hypotheses that: 1) specific depletion of respiratory complex proteins per mitochondrion and a decrease in mitochondrial mass impair substrate oxidation and promote IMCL accumulation in insulin resistance and T2DM; 2) these abnormalities increase ROS production which further compromises function in association with oxidative protein modifications, particularly in uncontrolled T2DM. To test these hypotheses, we will study metabolically-characterized insulin sensitive and resistant normoglycemic subjects over a range of body weight, and T2DM patients both in the untreated state and after euglycemic therapy to reverse the "glucose toxicity" component of insulin resistance. Perturbation studies will be performed before and after an insulin-sensitizing thiazolidinedione, and hypocaloric feeding & weight loss, in order to probe relationships with muscle mitochrondrial mass and morphology, and to study respiratory chain proteomics using 2D blue native gel electrophoresis and mass spectrometry. To assess mitochondrial function, we will measure carbohydrate and lipid substrate oxidation by high resolution respirotometry, activity of individual respiratory chain complexes I-IV, coupling status, ROS/RNS generation, and post-translational oxidative modifications affecting mitochondrial proteins. We will also examine whether discordant regulation between nuclear and mitochondrial genomes could underlie mitochondrial dysfunction. These studies will for the first time delineate functional and molecular defects in muscle mitochondria related to defects in substrate oxidation and IMCL in human insulin resistance.

描述（由申请人提供）：胰岛素抵抗是2型糖尿病（T2 DM）、代谢综合征和心血管疾病发病机制的核心，给患者带来了沉重的痛苦和医疗保健费用负担。直接原因涉及骨骼肌葡萄糖摄取刺激缺陷。胰岛素抵抗还与脂肪氧化和肌细胞内脂质（IMCL）积累异常有关，尽管分子机制尚不清楚。由于线粒体是负责脂质氧化，这是诱人的线粒体功能障碍的基础上解释增加IMCL，并有最近的证据支持这一观点。在过去的资助周期中，我们使用cDNA微阵列研究了人类肌肉中的差异基因表达，发现编码线粒体蛋白的多个基因在胰岛素抵抗中下调。这些数据，以及胰岛素抵抗涉及复合物IV蛋白的选择性耗竭的观察结果，使我们对骨骼肌中的线粒体蛋白质组和功能进行了更详细的检查。目前的提议结合了人体生理学和基本方法来测试以下假设：1）每个线粒体呼吸复合物蛋白的特异性消耗和线粒体质量的减少损害了底物氧化并促进了胰岛素抵抗和T2 DM中的IMCL积累; 2）这些异常增加了ROS产生，这进一步损害了与氧化蛋白修饰相关的功能，特别是在不受控制的T2 DM中。为了检验这些假设，我们将研究在一定体重范围内具有代谢特征的胰岛素敏感和抵抗的血糖正常受试者，以及处于未治疗状态和接受正常血糖治疗以逆转胰岛素抵抗的“葡萄糖毒性”成分后的T2 DM患者。扰动研究将在胰岛素增敏噻唑烷二酮和低热量喂养和体重减轻前后进行，以探索与肌肉线粒体质量和形态的关系，并使用2D蓝色天然凝胶电泳和质谱法研究呼吸链蛋白质组学。为了评估线粒体功能，我们将通过高分辨率呼吸测定法测量碳水化合物和脂质底物氧化、单个呼吸链复合物I-IV的活性、偶联状态、ROS/RNS生成和影响线粒体蛋白的翻译后氧化修饰。我们还将研究核和线粒体基因组之间的不协调调节是否可能导致线粒体功能障碍。这些研究将首次描述与人胰岛素抵抗中底物氧化和IMCL缺陷相关的肌肉线粒体功能和分子缺陷。

项目成果

Biological actions of insulin are differentially regulated by glucose and insulin in primary cultured adipocytes. Chronic ability to increase glycogen synthase activity.

原代培养的脂肪细胞中葡萄糖和胰岛素对胰岛素的生物学作用有不同的调节。

• DOI: 10.2337/diab.43.1.53
• 发表时间: 1994
• 期刊: Diabetes
• 影响因子: 7.7
• 作者: Lima,FB;Bao,S;Garvey,WT
• 通讯作者: Garvey,WT

Cardiometabolic disease risk in metabolically healthy and unhealthy obesity: Stability of metabolic health status in adults.

• DOI: 10.1002/oby.21344
• 发表时间: 2016-02
• 期刊: Obesity (Silver Spring, Md.)
• 作者: Guo F;Garvey WT
• 通讯作者: Garvey WT

Potential role for insulin and cycloheximide in regulating the intrinsic activity of glucose transporters in isolated rat adipocytes.

胰岛素和放线菌酮在调节离体大鼠脂肪细胞葡萄糖转运蛋白内在活性中的潜在作用。

• DOI: 10.1210/endo.133.6.8243322
• 发表时间: 1993
• 期刊: Endocrinology
• 影响因子: 4.8
• 作者: Karnieli,E;Garvey,WT;Olefsky,JM;Hueckstead,TP;Harel,C;Maianu,L;Armoni,M
• 通讯作者: Armoni,M

Muscle Rad expression and human metabolism: potential role of the novel Ras-related GTPase in energy expenditure and body composition.

肌肉 Rad 表达和人体代谢：新型 Ras 相关 GTP 酶在能量消耗和身体成分中的潜在作用。

• DOI: 10.2337/diab.46.3.444
• 发表时间: 1997
• 期刊: Diabetes
• 影响因子: 7.7
• 作者: Garvey,WT;Maianu,L;Kennedy,A;Wallace,P;Ganaway,E;Hamacher,LL;Yarnall,DP;Lenhard,JM;Burns,DK
• 通讯作者: Burns,DK

Deletion of the Toll-Like Receptor 5 Gene Per Se Does Not Determine the Gut Microbiome Profile That Induces Metabolic Syndrome: Environment Trumps Genotype.

• DOI: 10.1371/journal.pone.0150943
• 发表时间: 2016
• 期刊: PloS one
• 影响因子: 3.7
• 作者: Zhang W;Hartmann R;Tun HM;Elson CO;Khafipour E;Garvey WT
• 通讯作者: Garvey WT