Effect of Fish Oil Supplementation on Resting Energy Expenditure, Skeletal Muscle Membrane Composition and Metabolism in Elderly Subjects.
试验速览
- 阶段
- 不适用
- 入组人数
- 30
- 试验地点
- 2
- 主要终点
- Change in skeletal muscle sodium pump (Na/K ATPase) activity (umol/mg protein/hour)
研究概览
简要总结
Resting metabolic rate (RMR) declines by 1-2% per decade after 20 years of age. This reduction is linked to a decrease in fat free mass (FFM) (10-20%) and the rate of energy expenditure of tissues (Manini 2010).
It has also been shown that as we age there is a:
- Concomitant reduction in basal fat and carbohydrate oxidation, most likely due to the decrease in RMR than to a change in respiratory exchange ratio (RER) (St-Onge and Gallagher 2010).
- A change towards a more saturated membrane of different tissues (Rabini et al 2002).
Incorporation of omega-3s, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), into cell membranes may alter energy metabolism by:
- Increasing the rate at which proteins operate (Hulbert 2007).
- Promoting the release of EPA and DHA into the cytosol which will act as ligands for peroxisome proliferator-activated receptors (PPARs) (Calder 2011). PPARs play an important role in energy homeostasis by regulating genes involved in lipid metabolism (Kota et al 2005).
- Augmenting protein synthesis through activation of the mTOR-p70s6k pathway (Di Girolamo et al 2014).
Supplementation with fish oil in older males and females:
- Increases whole muscle phospholipid profile of EPA and DHA (Smith et al 2011).
- Increases lean body mass (LBM), RMR, and fatty acid oxidation (Logan et al unpublished)
- Decreases carbohydrate oxidation (Logan et al unplubished). Skeletal muscle (SM) accounts for 20-30% of RMR (Zurlo et al 1990, Manini 2010), therefore it is tempting to speculate that these changes may occur by some of the mechanisms described earlier, with skeletal muscle being an important contributor.
To date there are no studies that have examined the effect of n-3 supplementation (3g/day)* on plasma membrane fatty acid composition, RMR and substrate oxidation, and the possible mechanisms behind it.
Therefore the purpose of this study is to determine whether in older adults (female and male), supplementation with n-3 alters:
- RMR and fatty acid oxidation.
- Membrane composition of whole muscle and sarcolemma.
- Content of skeletal muscle membrane fatty acid transport proteins.
- Dose response of NaKATPase and SERCA efficiency
- Content of mitochondrial proteins
- Expression and content of PPARs and proteins involved in translocation of FA transporters (AMPK, ERK1/2, CamKII).
- Phosphorylation of AMPKα(THR172), ERK1/2(THR202 TYR204) and CaMKII(THR286).
- Proteomic profile of skeletal muscle.
- Body composition
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 60 Years 至 75 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Between 60 and 75 years old
- •Must currently practice a consistent diet and exercise regimen, and maintain this throughout the duration of the study
排除标准
- •Have any medical condition (no evidence of significant cardiovascular disease or organ dysfunction, including hypertension, dyslipidemia, and diabetes mellitus), and hospitalization or surgeries
- •Consume more than two meals of fish/wk and/or have taken an omega-3 supplement during the prior three months.
- •Have a BMI > 30 kg/m2
结局指标
主要结局
Change in skeletal muscle sodium pump (Na/K ATPase) activity (umol/mg protein/hour)
时间窗: Baseline and 12 weeks
Change in skeletal muscle sarcoplasmic reticulum calcium (SERCA) ATPase activity (umol/mg protein/hour)
时间窗: Baseline and 12 weeks
Change in skeletal muscle whole muscle membrane fatty acid composition from baseline
时间窗: Baseline and 12 weeks
次要结局
- Change in skeletal muscle content of mitochondrial proteins(Baseline and 12 weeks)
- Change in body composition(Baseline, 6 and 12 weeks)
- Change in skeletal muscle PPARs content(Baseline and 12 weeks)
- Change in skeletal muscle membrane fatty acid transporter content(Baseline and 12 weeks)
- Change in skeletal muscle phosphorylation of AMPKα(THR172), ERK1/2(THR202 TYR204) and CaMKII(THR286)(Baseline and 12 weeks)
- Change in whole body resting metabolic rate(Baseline, 6 and 12 weeks)
研究者
Lawrence Spriet
Professor and Chair Human Health and Nutritional Sciences
University of Guelph