Ectopic Lipid Accumulation and Reduced Glucose Tolerance in Elderly Adults Are Accompanied by Altered Skeletal Muscle Mitochondrial Activity
Ectopic Lipid Accumulation and Reduced Glucose Tolerance in Elderly Adults Are Accompanied by Altered Skeletal Muscle Mitochondrial Activity
复制标题
DOI：
10.1210/jc.2011-1798
复制
发表时间：
2012-01-01
影响因子：
5.8
通讯作者：
Ravussin, Eric
中科院分区：
文献类型：
--
作者：
Johannsen, Darcy L.;Conley, Kevin E.;Ravussin, Eric
内容：衰老与胰岛素抵抗和身体组成的不利变化有关，包括脂肪积累增加，特别是在内脏和异位仓库。最近的研究表明，骨骼肌线粒体活性可能是一些与年龄相关的代谢abnormals.Objective：我们的目的是测量线粒体的能力和耦合的股外侧肌在老年人和年轻人使用新的体内方法和线粒体活性代谢特征。设计：这是一个横断面研究。十四个久坐的年轻人（男7例，女7例，年龄20-34岁）和15名久坐的老年人（7名男性和8名女性，70-84岁）选择相似体重的非肥胖受试者通过磁共振成像和双能X射线吸收测定法进行身体组成的测量，口服葡萄糖耐量，以及通过P-31磁共振和光学光谱测定的体内线粒体活性。肌肉活检进行了在同一肌肉线粒体含量，抗氧化活性，纤维类型，和线粒体biogenesis.Results标记：老年志愿者减少线粒体容量（P = 0.05）和couplingefficiency下降的趋势（P = 0.08），尽管相似的线粒体含量和纤维类型分布。这伴随着更大的全身氧化应激（P = 0.007），更少的骨骼肌质量（P < 0.001），更多的脂肪组织在所有仓库（P < 0.001）。
Context: Aging is associated with insulin resistance and unfavorable changes in body composition including increased fat accumulation, particularly in visceral and ectopic depots. Recent studies suggest that skeletal muscle mitochondrial activity may underlie some age-associated metabolic abnormalities.Objective: Our objective was to measure mitochondrial capacity and coupling of the vastus lateralis muscle in elderly and young adults using novel in vivo approaches and relate mitochondrial activity to metabolic characteristics.Design: This was a cross-sectional study.Participants and Intervention: Fourteen sedentary young (seven males and seven females, 20-34 yr of age) and 15 sedentary elderly (seven males and eight females, 70-84 yr of age) nonobese subjects selected for similar body weight underwent measures of body composition by magnetic resonance imaging and dual-energy x-ray absorptiometry, oral glucose tolerance, and in vivo mitochondrial activity by P-31 magnetic resonance and optical spectroscopy. Muscle biopsy was carried out in the same muscle to measure mitochondrial content, antioxidant activity, fiber type, and markers of mitochondrial biogenesis.Results: Elderly volunteers had reduced mitochondrial capacity (P = 0.05) and a trend for decreased couplingefficiency (P = 0.08) despite similar mitochondrial content and fiber type distribution. This was accompanied by greater whole-body oxidative stress (P = 0.007), less skeletal muscle mass (P < 0.001), more adipose tissue in all depots (P