Schenk Simon, Horowitz Jeffrey F
Substrate Metabolism Laboratory, Division of Kinesiology, University of Michigan, 401 Washtenaw Ave., Ann Arbor, MI 48109-2214, USA.
Am J Physiol Endocrinol Metab. 2006 Aug;291(2):E254-60. doi: 10.1152/ajpendo.00051.2006. Epub 2006 May 2.
Although the increase in fatty acid oxidation after endurance exercise training has been linked with improvements in insulin sensitivity and overall metabolic health, the mechanisms responsible for increasing fatty acid oxidation after exercise training are not completely understood. The primary aim of this study was to determine the effect of adding endurance exercise training to a weight loss program on fat oxidation and the colocalization of the fatty acid translocase FAT/CD36 with carnitine palmitoyltransferase I (CPT I) in human skeletal muscle. We measured postabsorptive fat oxidation and acquired a muscle sample from abdominally obese women before and after 12% body weight loss through either dietary intervention with endurance exercise training (EX + DIET) or dietary intervention without endurance exercise training (DIET). Immunoprecipitation techniques were used on these muscle samples to determine whether the association between FAT/CD36 and CPT I is altered after DIET and/or EX + DIET. FAT/CD36 was found to coimmunoprecipitate with CPT I, and the amount of FAT/CD36 that coimmunoprecipitated with CPT I increased by approximately 25% after EX + DIET (P < 0.005) but was unchanged after DIET. In addition, the increase in the amount of FAT/CD36 that coimmunoprecipitated with CPT I in EX + DIET was strongly correlated with the increase in whole body fat oxidation (R2 = 0.857, P < 0.003). In conclusion, the findings from this study indicate that exercise training alters the localization of FAT/CD36 and increases its association with CPT I, which may help augment fat oxidation.
尽管耐力运动训练后脂肪酸氧化增加与胰岛素敏感性改善及整体代谢健康状况提升有关，但运动训练后脂肪酸氧化增加的机制尚未完全明确。本研究的主要目的是确定在减肥计划中加入耐力运动训练对人体骨骼肌中脂肪氧化以及脂肪酸转运蛋白FAT/CD36与肉碱棕榈酰转移酶I（CPT I）共定位的影响。我们测量了空腹脂肪氧化情况，并在腹部肥胖女性通过饮食干预加耐力运动训练（EX + DIET）或仅饮食干预（DIET）减重12%体重前后采集肌肉样本。对这些肌肉样本采用免疫沉淀技术，以确定DIET和/或EX + DIET后FAT/CD36与CPT I之间的关联是否改变。发现FAT/CD36与CPT I能共免疫沉淀，且EX + DIET后与CPT I共免疫沉淀的FAT/CD36量增加了约25%（P < 0.005），而DIET后无变化。此外，EX + DIET中与CPT I共免疫沉淀的FAT/CD36量的增加与全身脂肪氧化的增加密切相关（R2 = 0.857，P < 0.003）。总之，本研究结果表明运动训练改变了FAT/CD36的定位，并增加了其与CPT I的关联，这可能有助于增强脂肪氧化。
