Regulation of Muscle ATP Synthase Beta Subunit Metabolism in Obesity

肥胖中肌肉 ATP 合酶 β 亚基代谢的调节

• 批准号: 8539598
• 负责人: Christos S Katsanos
• 金额: $ 32.58万
• 依托单位: ARIZONA STATE UNIVERSITY-TEMPE CAMPUS
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-04 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8539598
• 关键词: Acute; Adenosine Triphosphate; Aerobic Exercise; Amino Acids; Anabolism; Bioenergetics; Biopsy; Catalytic Domain; Cell physiology; Development; Effectiveness of Interventions; Exercise; F1-ATPase; Goals; High Pressure Liquid Chromatography; Human; Individual; Infusion procedures; Insulin Resistance; Intervention; Intravenous; Knowledge; Label; Lead; Leucine; Mass Fragmentography; Mass Spectrum Analysis; Measurement; Measures; Messenger RNA; Metabolic; Metabolism; Mitochondria; Mitochondrial Proteins; Muscle; Muscle Mitochondria; Muscle Proteins; Non obese; Obesity; Outcome; Oxidative Stress; Peptides; Physical activity; Physiological; Plasma; Production; Protein Biosynthesis; Proteins; Qualifying; Reactive Oxygen Species; Regulation; Research; Role; Saline; Sampling; Skeletal Muscle; Stimulus; Testing; Time; Translating; base; improved; in vivo; lifestyle intervention; muscle metabolism; protein degradation; protein expression; protein metabolism; sound; stable isotope; tandem mass spectrometry

DESCRIPTION (provided by applicant): Obesity is associated with reduced adenosine triphosphate (ATP) turnover in skeletal muscle. This condition results in unfavorable outcomes, proposed to range from decreased capacity for physical activity, to impaired activation of physiological mechanisms associated with cell function, to increased oxidative stress and the development of insulin resistance. The abundance of the beta subunit of the ATP synthase (¿ -F1-ATPase) in muscle mitochondria is decreased in obese, insulin-resistant individuals. ¿ -F1- ATPase makes up the catalytic site of the ATP synthase, and it is a rate-limiting component of ATP synthesis. We propose that muscle ¿ -F1-ATPase synthesis is reduced in obesity. Because measurement of stable isotopic enrichment of individual proteins is not practical using traditional gas chromatography-mass spectrometry approaches for proteins that are found in small amounts in skeletal muscle, we have developed an approach to quantify the isotopic enrichment of in vivo labeled muscle ¿ -F1-ATPase using HPLC-ESI-MS/MS. It is based on the quantification of the isotopic enrichment of a unique peptide of muscle ¿ -F1-ATPase. Using this approach we will test the hypothesis that the rate of muscle ¿ -F1-ATPase synthesis is reduced in obese individuals. We also intend to investigate the effects of increased plasma amino acid concentrations as well as exercise on stimulating the synthesis rate of ¿ -F1-ATPase in skeletal muscle of both obese and non-obese individuals. Muscle ¿ -F1-ATPase synthesis, which is the main end-point of this proposal, will be determined using an intravenous constant infusion of d9-leucine in obese and non-obese subjects, and by measuring the d9-leucine enrichment of a ¿ -F1-ATPase peptide. The following conditions will be tested: saline infusion (control), amino acid infusion, aerobic exercise, and a combination of aerobic exercise with amino acid infusion. These studies will for the first time determinate the rate of synthesis of muscle ¿ -F1-ATPase in humans in vivo, and how it is altered by interventions known to promote muscle protein anabolism. Overall, the results of these studies will lead to better understanding of the mechanisms regulating the abundance of ¿ -F1-ATPase in skeletal muscle in both obese and non-obese individuals. Further, they will provide scientific knowledge to base lifestyle interventions to improve muscle ATP turnover in obese individuals.

描述（由申请方提供）：肥胖与骨骼肌中三磷酸腺苷（ATP）周转减少有关。这种情况导致不利的结果，提出范围从降低的体力活动能力，到与细胞功能相关的生理机制的激活受损，到增加的氧化应激和胰岛素抵抗的发展。在肥胖、胰岛素抵抗的个体中，肌肉线粒体中ATP合酶β亚基（<$-F1-ATP酶）的丰度降低。<$-F1-ATP酶构成ATP合成酶的催化位点，并且它是ATP合成的限速组分。我们认为，肌肉<$-F1-ATP酶合成减少肥胖。 由于使用传统的气相色谱-质谱法测量单个蛋白质的稳定同位素富集对于在骨骼肌中少量发现的蛋白质是不实际的，我们已经开发了一种使用HPLC-ESI-MS/MS定量体内标记的肌肉<$F1-ATP酶的同位素富集的方法。-F1-ATP酶。使用这种方法，我们将测试的假设，肌肉<$-F1-ATP酶合成的速度是减少肥胖的人。我们还打算研究增加血浆氨基酸浓度以及运动对刺激肥胖和非肥胖个体骨骼肌中<$-F1-ATP酶合成速率的影响。 肌肉？-F1-ATP酶的合成，这是该建议的主要终点，将使用在肥胖和非肥胖受试者中静脉内恒定输注d9-亮氨酸，并通过测量Δ-F1-ATP酶肽的d9-亮氨酸富集来确定。将测试以下条件：生理盐水输注（对照）、氨基酸输注、有氧运动以及有氧运动与氨基酸输注的组合。这些研究将首次确定人体体内肌肉<$-F1-ATP酶的合成速率，以及已知促进肌肉蛋白质合成的干预措施如何改变它。总的来说，这些研究的结果将导致更好地理解肥胖和非肥胖个体骨骼肌中<$-F1-ATP酶丰度的调节机制。此外，他们将提供科学知识，以基础生活方式干预，以改善肥胖个体的肌肉ATP周转率。