Lipid mediators of insulin resistance: ceramide signalling down-regulates GLUT4 gene transcription in 3T3-L1 adipocytes

Biochem J. 1996 Oct 1;319 ( Pt 1)(Pt 1):179-84. doi: 10.1042/bj3190179.


We have previously demonstrated that chronic exposure of 3T3-L1 adipocytes to tumour necrosis factor-alpha (TNF) resulted in a marked decrease (approximately 90%) in cellular GLUT4 (insulin-responsive glucose transporter) mRNA content as a result of a decreased transcription rate of the GLUT4 gene (approximately 75%) and a reduced half-life of its mRNA (9 to 4.5 h). Investigation of the signalling mechanism responsible for this regulation demonstrated that in the 3T3-L1 adipocytes, sphingomyelin levels decreased to 50% of control levels within 40 min of exposure to TNF, consistent with activation of a sphingomyelinase. In the same manner as with TNF, treatment of the adipocytes with 1-3 microM C6-ceramide, a membrane-permeable analogue of ceramide, decreased GLUT4 mRNA content by approximately 60%. Subsequent investigations revealed that transcription of the GLUT4 gene was reduced by approximately 65% in response to C6-ceramide, demonstrating that the decrease in mRNA content is mediated by a reduction in the transcription of the genc. No effect on GLUT4 mRNA stability was observed after exposure of the adipocytes to C6-ceramide. These observations are interesting in light of our previous data demonstrating that TNF affects both GLUT4 transcription and mRNA stability in the 3T3-L1 adipocytes. In conclusion, the effect of ceramide on GLUT4 gene expression is at the level of transcription, suggesting that another pathway controls mRNA stability. These data establish that ceramide-initiated signal transduction pathways exist within the adipocyte, and provide a potential mechanism for control of GLUT4 gene expression.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 3T3 Cells
  • 5,8,11,14-Eicosatetraynoic Acid / metabolism
  • Adipose Tissue / drug effects*
  • Adipose Tissue / metabolism
  • Animals
  • Arachidonic Acid / metabolism
  • Ceramides / pharmacology*
  • Choline / metabolism
  • Down-Regulation
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme Activation
  • Gene Expression Regulation*
  • Glucose Transporter Type 4
  • Insulin Resistance*
  • Isoenzymes / metabolism
  • Mice
  • Monosaccharide Transport Proteins / genetics*
  • Muscle Proteins*
  • NF-kappa B / metabolism
  • Phosphorylation
  • Protein Kinase C / metabolism
  • Protein Kinase C-delta
  • RNA, Messenger / metabolism
  • Sphingomyelin Phosphodiesterase / metabolism
  • Sphingomyelins / metabolism
  • Transcription, Genetic / drug effects
  • Tumor Necrosis Factor-alpha / pharmacology


  • Ceramides
  • Glucose Transporter Type 4
  • Isoenzymes
  • Monosaccharide Transport Proteins
  • Muscle Proteins
  • NF-kappa B
  • RNA, Messenger
  • Slc2a4 protein, mouse
  • Sphingomyelins
  • Tumor Necrosis Factor-alpha
  • N-caproylsphingosine
  • 5,8,11,14-Eicosatetraynoic Acid
  • Arachidonic Acid
  • Prkcd protein, mouse
  • Protein Kinase C
  • Protein Kinase C-delta
  • Sphingomyelin Phosphodiesterase
  • Choline