Insulin acutely upregulates protein expression of the fatty acid transporter CD36 in human skeletal muscle in vivo

J Physiol Pharmacol. 2008 Mar;59(1):77-83.

Abstract

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.

Publication types

  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • CD36 Antigens / drug effects*
  • CD36 Antigens / metabolism
  • Cytosol / metabolism
  • Fatty Acid-Binding Proteins / metabolism
  • Fatty Acids / metabolism
  • Glucose Clamp Technique
  • Glucose Tolerance Test
  • Humans
  • Insulin / blood
  • Insulin / physiology*
  • Insulin Resistance / physiology*
  • Male
  • Middle Aged
  • Muscle, Skeletal / metabolism
  • Obesity / metabolism*
  • Triglycerides / metabolism
  • Up-Regulation / drug effects

Substances

  • CD36 Antigens
  • Fatty Acid-Binding Proteins
  • Fatty Acids
  • Insulin
  • Triglycerides