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.
|Journal||Journal of Physiology and Pharmacology|
|Publication status||Published - 2008|