FATP1 mediates fatty acid-induced activation of AMPK in 3T3-L1 adipocytes

Biochem Biophys Res Commun. 2009 Sep 18;387(2):234-8. doi: 10.1016/j.bbrc.2009.06.114. Epub 2009 Jun 26.

Abstract

Fatty acid transport proteins are integral membrane acyl-CoA synthetases implicated in adipocyte fatty acid influx and esterification. FATP-dependent production of AMP was evaluated using FATP4 proteoliposomes, and fatty acid-dependent activation of AMP-activated protein kinase (AMPK) was assessed in 3T3-L1 adipocytes. Insulin-stimulated fatty acid influx (palmitate or arachidonate) into cultured adipocytes resulted in an increase in the phosphorylation of AMPK and its downstream target acetyl-CoA carboxylase. Consistent with the activation of AMPK, palmitate uptake into 3T3-L1 adipocytes resulted in an increase in intracellular [AMP]/[ATP]. The fatty acid-induced increase in AMPK activation was attenuated in a cell line expressing shRNA targeting FATP1. Taken together, these results demonstrate that, in adipocytes, insulin-stimulated fatty acid influx mediated by FATP1 regulates AMPK and provides a potential regulatory mechanism for balancing de novo production of fatty acids from glucose metabolism with influx of preformed fatty acids via phosphorylation of acetyl-CoA carboxylase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3-L1 Cells
  • AMP-Activated Protein Kinase Kinases
  • Adipocytes / enzymology*
  • Animals
  • Coenzyme A Ligases / metabolism
  • Enzyme Activation
  • Fatty Acid Transport Proteins / genetics
  • Fatty Acid Transport Proteins / metabolism*
  • Fatty Acids / metabolism*
  • Fatty Acids / pharmacology
  • Insulin / metabolism*
  • Insulin / pharmacology
  • Mice
  • Phosphorylation
  • Protein Kinases / biosynthesis*

Substances

  • Fatty Acid Transport Proteins
  • Fatty Acids
  • Insulin
  • Slc27a1 protein, mouse
  • Protein Kinases
  • AMP-Activated Protein Kinase Kinases
  • Coenzyme A Ligases