Nutritional Stimulation of Muscle Protein Synthesis and Metabolic Rate After Bariatric Surgery
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 40
- 试验地点
- 2
- 主要终点
- Lean body mass
研究概览
简要总结
Bariatric surgery is an effective treatment for severe obesity but results in loss of muscle mass. The investigators will test the hypothesis that consumption of an Essential Amino Acid-based nutritional formulation will maintain muscle mass while stimulating fat loss after bariatric surgery.
详细描述
- Objectives
Bariatric surgery has become a common treatment for severe obesity, and results in a loss of fat mass. However, muscle mass is also lost following bariatric surgery. It is the investigators' overarching premise that consumption of the Essential Amino Acid-based nutritional formulation following bariatric surgery will preserve muscle mass by stimulating muscle protein synthesis. As a result, the energy utilization associated with the combination of maintained muscle mass and stimulated muscle protein synthesis will counter the decrease in metabolic rate that normally occurs in hypocaloric circumstances. Maintenance of a higher total energy expenditure by Essential Amino Acid consumption will accelerate loss of body fat, as well as accelerate loss of body weight. The investigators further propose that consumption of an Essential Amino Acid-based nutritional formulation will reduce muscle intra-cellular lipid accumulation, which will translate to greater improvements in glucose homeostasis and muscle protein metabolism. The loss of muscle mass in those with obesity undergoing rapid weight loss post-bariatric surgery, is not in itself, a disease or a medical condition.
The following aims will test specific hypotheses related to the scientific premise:
Aim 1. Supplementation of the usual diet following bariatric surgery with a proprietary Essential Amino Acid-based nutritional formulation twice per day for 6 months will maintain muscle mass and reduce fat mass more than supplementation of the diet with an isonitrogenous amount of whey protein. Muscle mass will be directly measured using a novel tracer-dilution technique using deuterium-labeled creatine. Fat mass and lean body mass will be measured by Dual-energy X-ray absorptiometry.
Aim 2. Muscle protein fractional synthetic rate and total muscle protein synthesis (muscle mass x fractional synthetic rate) will decline less from pre-surgery values in participants consuming the Essential Amino Acid-based nutritional formulation as compared to whey protein. Muscle protein fractional synthetic rate will be measured by the novel "virtual biopsy" method, which provides an integrated value over three weeks.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
盲法说明
After obtaining consent, the patient will receive supplement assignment based on computer-generated, block-randomization with stratification by sex. The intervention and control supplements are packaged, sealed and labeled as group A or B by The Amino Co. The packets are sent to Oregon Health & Science University at study start and stored at room temperature in the investigators' laboratory. The Oregon Health & Science University investigators are unaware of which supplements are packaged as group A or B. The research coordinator is responsible for completing the randomization process using a table created by the statistician. The stratification/randomization assignments are kept in a password-protected file; the password known only to the research coordinator and statistician. The powdered and reconstituted forms of the supplements are indistinguishable to an observer.
入排标准
- 年龄范围
- 18 Years 至 60 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •A determination to proceed with bariatric surgery
- •Roux-en-Y gastric bypass or sleeve gastrectomy
- •Absence of any exclusion
排除标准
- •Contraindications to Magnetic Resonance Spectroscopy/Magnetic Resonance Imaging
- •greater than 450 pounds (scan table limit)
- •Renal Failure requiring dialysis
- •Liver disease as indicated by bilirubin >2 or Fibrosis-4 score ≥6
- •Cardiac disease such as Left Ventricular Assist Device requirement
- •Uncontrolled diabetes as indicated by Hemoglobin A1c >8
- •Positive pregnancy test (for participants in whom pregnancy is possible)
- •Any other exclusion per indication of clinical surgeon
- •Refusal to consume study formula
结局指标
主要结局
Lean body mass
时间窗: 6 months after bariatric surgery
Lean body mass in kilograms
Total energy expenditure
时间窗: 6 months after bariatric surgery
Total energy expenditure in kilocalories per day
Muscle mass
时间窗: 6 months after bariatric surgery
Muscle mass in kilograms
次要结局
- Liver fat mass(6 months after bariatric surgery)
- Resting energy expenditure(6 months after bariatric surgery)
- Percent muscle fat(6 months after bariatric surgery)
- Muscle protein synthetic rate(6 months after bariatric surgery)
- Visceral fat mass(6 months after bariatric surgery)
- Diet induced thermogenesis(6 months after bariatric surgery)
- Whole body fat mass(6 months after bariatric surgery)
- Essential amino acids(6 months after bariatric surgery)
- Dietary intake (Objective)(6 months after bariatric surgery)
- Physical activity (Objective)(6 months after bariatric surgery)
- Subcutaneous fat mass(6 months after bariatric surgery)
- Glucose(6 months after bariatric surgery)
- Insulin(6 months after bariatric surgery)
- Muscle protein fractional synthetic rate(6 months after bariatric surgery)
- Weight(6 months after bariatric surgery)
研究者
Nancy Puzziferri
Assistant Professor of Surgery
Oregon Health and Science University