Institute for Clinical Chemistry and Pathobiochemistry, Department for Diagnostic Laboratory Medicine, University Hospital Tübingen, Tübingen, Germany.
Department of Sports Medicine, University Hospital Tübingen, Tübingen, Germany.
J Clin Endocrinol Metab. 2020 Nov 1;105(11). doi: 10.1210/clinem/dgaa571.
Exercise training improves glycemic control and increases mitochondrial content and respiration capacity in skeletal muscle. Rodent studies suggest that training increases mitochondrial respiration in adipose tissue.
To assess the effects of endurance training on respiratory capacities of human skeletal muscle and abdominal subcutaneous adipose tissue and to study the correlation with improvement in insulin sensitivity.
Using high-resolution respirometry, we analyzed biopsies from 25 sedentary (VO2 peak 25.1 ± 4.0 VO2 mL/[kg*min]) subjects (16 female, 9 male; 29.8 ± 8.4 years) with obesity (body mass index [BMI] 31.5 ± 4.3 kg/m2), who did not have diabetes. They performed a supervised endurance training over 8 weeks (3 × 1 hour/week at 80% VO2 peak).
Based on change in insulin sensitivity after intervention (using the Matsuda insulin sensitivity index [ISIMats]), subjects were grouped in subgroups as responders (>15% increase in ISIMats) and low-responders. The response in ISIMats was correlated to a reduction of subcutaneous and visceral adipose tissue volume. Both groups exhibited similar increases in fitness, respiratory capacity, and abundance of mitochondrial enzymes in skeletal muscle fibers. Respiratory capacities in subcutaneous adipose tissue were not altered by the intervention. Compared with muscle fibers, adipose tissue respiration showed a preference for β-oxidation and complex II substrates. Respiratory capacities were higher in adipose tissue from female participants.
Our data show that the improvement of peripheral insulin sensitivity after endurance training is not directly related to an increase in mitochondrial respiratory capacities in skeletal muscle and occurs without an increase in the respiratory capacity of subcutaneous adipose tissue.
运动训练可改善血糖控制，并增加骨骼肌中的线粒体含量和呼吸能力。啮齿动物研究表明，训练可增加脂肪组织中的线粒体呼吸。
评估耐力训练对人体骨骼肌和腹部皮下脂肪组织呼吸能力的影响，并研究其与胰岛素敏感性改善的相关性。
使用高分辨率呼吸测量法，我们分析了 25 名久坐不动的肥胖受试者（VO2 峰值 25.1 ± 4.0 VO2 mL/[kg*min]）的活检样本，这些受试者（16 名女性，9 名男性；29.8 ± 8.4 岁）没有糖尿病，且身体质量指数（BMI）为 31.5 ± 4.3 kg/m2。他们接受了 8 周的监督耐力训练（3 次/周，每次 1 小时，强度为 80% VO2 峰值）。
根据干预后胰岛素敏感性的变化（使用 Matsuda 胰岛素敏感性指数 [ISIMats]），将受试者分为高反应组（ISIMats 增加超过 15%）和低反应组。ISIMats 的反应与皮下和内脏脂肪组织体积的减少相关。两组的适应性、骨骼肌纤维的呼吸能力和线粒体酶的丰度均有类似的增加。干预对皮下脂肪组织的呼吸能力没有影响。与肌肉纤维相比，脂肪组织呼吸对β氧化和复合物 II 底物有偏好。女性参与者的脂肪组织呼吸能力更高。
我们的数据表明，耐力训练后外周胰岛素敏感性的改善与骨骼肌中线粒体呼吸能力的增加没有直接关系，并且不会导致皮下脂肪组织呼吸能力的增加。
