MOLECULAR REGULATION OF MUSCLE GLUCOSE METABOLISM (AIMS 2A, 2B, 3)
试验速览
- 阶段
- 不适用
- 入组人数
- 72
- 试验地点
- 1
- 主要终点
- ANT Acetylation
研究概览
简要总结
The molecular nature of insulin resistance in human muscle is still incompletely defined. Our data indicate that acetylation of mitochondrial proteins in humans is regulated by muscle contraction and is dysregulated in insulin resistance. Poor function of mitochondria in skeletal muscle is a hallmark of insulin resistance in skeletal muscle. We propose to use a combination of clinical research and mass spectrometry techniques to determine how the cytosolic and mitochondrial protein acetylation is regulated by muscle contraction in insulin sensitive and resistant human volunteers. We will test the hypothesis that mitochondrial protein acetylation is decreased to a greater degree following a bout of exercise in insulin sensitive than in insulin resistant human muscle. Using these techniques we also propose to determine how acetylation of mitochondrial adenine nucleotide translocase (ANT1) at lysines 10, 23, and 92 regulates ANT1 structure and function. Finally, we propose 4) to use a combination of molecular modeling and in vitro assays together with the approach developed in Aim 3 to characterize the role of acetylation in other mitochondrial proteins. Protein targets for this aim will be prioritized based on the potential role of the protein in insulin resistance or mitochondrial function as well as dysregulation of its acetylation state in insulin resistant muscle.
详细描述
The purpose of this project has been to define the molecular basis for insulin resistance in human muscle. The preceding two cycles of this project were devoted to using proteomics approaches to map and quantify serine/threonine (S/T) phosphorylation sites on insulin receptor substrate (IRS)-1 in skeletal muscle from healthy and insulin resistant humans.
Recent proteomics experiments reveal that another protein modification, lysine acetylation, is more common in non-histone proteins than has been recognized. There are no data, to our knowledge, regarding a relationship between insulin resistance in vivo in human muscle and protein acetylation. We have used proteomics techniques to discover a number of lysine acetylation sites in skeletal muscle proteins in vivo in humans, and this is prominent in mitochondrial proteins. Preliminary data show that mitochondrial protein acetylation is regulated by muscle contraction, and that this response is reduced in insulin resistance. Finally, the mitochondrial inner membrane protein adenine nucleotide translocase (ANT)1 was abundantly acetylated under resting conditions, and its deacetylation in response to contraction was reduced in insulin resistance. Because ANT1 exerts significant physiological control strength for ADP/ATP exchange, and because mitochondrial function is altered in insulin resistance, it is important to characterize this abnormality. Therefore, in order to determine how abnormalities in regulation of lysine acetylation characterize insulin resistant muscle, we propose:
- To determine how the cytosolic and mitochondrial protein acetylomes are regulated by muscle contraction in insulin sensitive and resistant human volunteers. We will test the hypotheses that:
a. There is differential acetylation of cytosolic or mitochondrial proteins in insulin resistance.
b. Mitochondrial protein acetylation is decreased to a greater degree following a bout of exercise in insulin sensitive than in insulin resistant human muscle.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 21 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Aim 2a. Subjects. Two groups (aged 21-65) will be studied: lean (BMI<25), healthy insulin sensitive subjects, and obese (BMI>30) nondiabetics 20 subjects will be enrolled
- •Subjects must be able to communicate meaningfully with the investigator and must be legally competent to provide written informed consent.
- •Subjects may be of either sex with age as described in each protocol. Female subjects must be non-lactating and will be eligible only if they have a negative pregnancy test throughout the study period.
- •Subjects must range in age as described in each specific protocol.
- •Subjects must have the following laboratory values:
- •Hematocrit ≥ 35 vol% Serum creatinine ≤ 1.6 mg/dl AST (SGOT) < 2 times upper limit of normal ALT (SGPT) < 2 times upper limit of normal Alkaline phosphatase < 2 times upper limit of normal Triglycerides < 150 mg/dl. PT 11.7 -14.3 (During Liposyn/heparin infusion, PT will be determined to insure that it is < 1.5-2.0 times the normal value.) PTT 23.0-37.
- •Aim 2b (muscle contraction and acetylation). Subjects. Two groups (aged 21-65) will be studied: lean (BMI<25), healthy insulin sensitive subjects, and obese (BMI>30) 32 subjects will be enrolled
- •Inclusion Criteria
- •Subjects must be able to communicate meaningfully with the investigator and must be legally competent to provide written informed consent.
- •Subjects may be of either sex with age as described in each protocol. Female subjects must be non-lactating and will be eligible only if they have a negative pregnancy test throughout the study period.
- •Subjects must range in age as described in each specific protocol.
- •Subjects must have the following laboratory values:
- •Hematocrit ≥ 35 vol% Serum creatinine ≤ 1.6 mg/dl AST (SGOT) < 2 times upper limit of normal ALT (SGPT) < 2 times upper limit of normal Alkaline phosphatase < 2 times upper limit of normal Triglycerides < 150 mg/dl. PT 11.7 -14.3 (During Liposyn/heparin infusion, PT will be determined to insure that it is < 1.5-2.0 times the normal value.) PTT 23.0-37.
- •Aim 3 Subjects. Two groups (aged 21-65) will be studied: lean (BMI<25), healthy insulin sensitive subjects, and obese (BMI>30) 20 subjects will be enrolled.
- •Inclusion Criteria
- •Subjects must be able to communicate meaningfully with the investigator and must be legally competent to provide written informed consent.
- •Subjects may be of either sex with age as described in each protocol. Female subjects must be non-lactating and will be eligible only if they have a negative pregnancy test throughout the study period.
- •Subjects must range in age as described in each specific protocol.
- •Subjects must have the following laboratory values:
- •Hematocrit ≥ 35 vol% Serum creatinine ≤ 1.6 mg/dl AST (SGOT) < 2 times upper limit of normal ALT (SGPT) < 2 times upper limit of normal Alkaline phosphatase < 2 times upper limit of normal Triglycerides < 150 mg/dl. INR < 1.3
排除标准
- •Subjects must not be receiving any of the following medications: thiazide or furosemide diuretics, beta-blockers, or other chronic medications with known adverse effects on glucose tolerance levels unless the patient has been on a stable dose of such agents for the past three months before entry into the study. Subjects may be taking a stable dose of estrogens or other hormonal replacement therapy, if the subject has been on these agents for the prior three months. Subjects taking systemic glucocorticoids are excluded.
- •Subjects with a history of clinically significant heart disease (New York Heart Classification greater than grade II; more than non-specific ST-T wave changes on the EKG), peripheral vascular disease (history of claudication), or pulmonary disease (dyspnea on exertion of one flight or less; abnormal breath sounds on auscultation) will not be studied.
- •Recent systemic or pulmonary embolus, untreated high-risk proliferative retinopathy, recent retinal hemorrhage, uncontrolled hypertension, systolic BP>180, diastolic BP>105, autonomic neuropathy, resting heart rate >100, electrolyte abnormalities.
- •Aim 2b Exclusion Criteria
- •Subjects must not be receiving any of the following medications: thiazide or furosemide diuretics, beta-blockers, or other chronic medications with known adverse effects on glucose tolerance levels unless the patient has been on a stable dose of such agents for the past three months before entry into the study. Subjects may be taking a stable dose of estrogens or other hormonal replacement therapy, if the subject has been on these agents for the prior three months. Subjects taking systemic glucocorticoids are excluded.
- •Subjects with a history of clinically significant heart disease (New York Heart Classification greater than grade II; more than non-specific ST-T wave changes on the EKG), peripheral vascular disease (history of claudication), or pulmonary disease (dyspnea on exertion of one flight or less; abnormal breath sounds on auscultation) will not be studied.
- •Recent systemic or pulmonary embolus, untreated high-risk proliferative retinopathy, recent retinal hemorrhage, uncontrolled hypertension, systolic BP>180, diastolic BP>105, autonomic neuropathy, resting heart rate >100, electrolyte abnormalities.
- •Aim 3 Exclusion Criteria
- •Subjects must not be receiving any of the following medications: thiazide or furosemide diuretics, beta-blockers, or other chronic medications with known adverse effects on glucose tolerance levels unless the patient has been on a stable dose of such agents for the past three months before entry into the study. Subjects may be taking a stable dose of estrogens or other hormonal replacement therapy, if the subject has been on these agents for the prior three months. Subjects taking systemic glucocorticoids are excluded.
- •Subjects with a history of clinically significant heart disease (New York Heart Classification greater than grade II; more than non-specific ST-T wave changes on the EKG), peripheral vascular disease (history of claudication), or pulmonary disease (dyspnea on exertion of one flight or less; abnormal breath sounds on auscultation) will not be studied.
- •Recent systemic or pulmonary embolus, untreated high-risk proliferative retinopathy, recent retinal hemorrhage, uncontrolled hypertension, systolic BP>180, diastolic BP>105, autonomic neuropathy, resting heart rate >100, electrolyte abnormalities.
- •Healthy controls with BMI less than 25 who have first degree relatives with Type 2 diabetes are at high risk for insulin resistance, this is an exclusion for this study.
结局指标
主要结局
ANT Acetylation
时间窗: 2013-2017
Acetylation of adenine nucleotide translocase 1 at lysine 23 in human muscle.
次要结局
未报告次要终点
研究者
Lawrence Mandarino
Professor of Medicine
University of Arizona