Corpeleijn E, Pelsers M M A L, Soenen S, Mensink M, Bouwman F G, Kooi M E, Saris W H M, Glatz J F C, Blaak E E
From the Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands.
J Physiol Pharmacol. 2008 Mar;59(1):77-83.
Enhanced fatty acid uptake may lead to the accumulation of lipid intermediates. This is related to insulin resistance and type 2 diabetes mellitus. Rodent studies suggest that fatty acid transporters are acutely regulated by insulin. We investigated differences in fatty acid transporter content before and at the end of a hyperinsulinemic euglycemic clamp in skeletal muscle (m. vastus lateralis) of obese, glucose-intolerant men (IGT) and obese normal glucose tolerant controls (NGT). The fatty acid transporter FAT/CD36 protein content increased 1.5-fold (P < 0.05) after 3-hrs of insulin stimulation with no difference between IGT and control subjects. No change was seen in cytosolic fatty acid binding protein (FABPc) protein content. The increase in FAT/CD36 protein content was positively related to insulin resistance as measured during the clamp (r = 0.56, P < 0.05). An increase in FAT/CD36 protein content in skeletal muscle may result in a higher fractional extraction of fatty acids (larger relative uptake) after a meal, enhancing triglyceride accumulation in the muscle. We conclude that also in obese humans the FAT/CD36 protein content in skeletal muscle is dynamically regulated by insulin in vivo on the short term.
脂肪酸摄取增加可能导致脂质中间体的积累。这与胰岛素抵抗和2型糖尿病有关。啮齿动物研究表明，脂肪酸转运蛋白受胰岛素急性调节。我们调查了肥胖、糖耐量受损男性（IGT）和肥胖糖耐量正常对照组（NGT）的骨骼肌（股外侧肌）在高胰岛素正常血糖钳夹试验开始前和结束时脂肪酸转运蛋白含量的差异。胰岛素刺激3小时后，脂肪酸转运蛋白FAT/CD36的蛋白质含量增加了1.5倍（P<0.05），IGT组和对照组之间无差异。胞质脂肪酸结合蛋白（FABPc）的蛋白质含量未见变化。FAT/CD36蛋白质含量的增加与钳夹试验期间测得的胰岛素抵抗呈正相关（r=0.56，P<0.05）。骨骼肌中FAT/CD36蛋白质含量的增加可能导致餐后脂肪酸的更高分数提取（更大的相对摄取），从而增强肌肉中甘油三酯的积累。我们得出结论，在肥胖人群中，骨骼肌中的FAT/CD36蛋白质含量在体内短期内也受胰岛素的动态调节。
