Interleukin-6 promotes 2-deoxyglucose uptake through p44/42 MAPKs activation via Ca2+/PKC and EGF receptor in primary cultured chicken hepatocytes

J Cell Physiol. 2009 Mar;218(3):643-52. doi: 10.1002/jcp.21641.

Abstract

Interleukin-6 (IL-6) is involved in a variety of biological responses, including the glucose metabolism and cell growth, which is a critical physiological function requiring multiple metabolic pathways. Therefore, in the present study, we examined the effect of IL-6 on 2-deoxyglucose (2-DG) uptake and the related signaling pathways in primary cultured chicken hepatocytes. IL-6 increased 2-DG uptake in a time- (> or =4 h) and a dose -(> or =5 ng/ml) dependent manner. Indeed, IL-6 increased GLUT-2 mRNA and protein expression as well as 2-DG uptake, which were blocked by actinomycin D (AD, transcription inhibitor) and cycloheximide (CHX, translation inhibitor). IL-6 (10 ng/ml) increased the level of IL-6Ralpha and glycoprotein (gp) 130 (IL-6Rbeta) protein expressions. IL-6 increased Janus Kinase (JAK)-2, signal transducer and activator of transcription (STAT)-3 phosphorylation, intracellular Ca(2+) concentration, and PKC phosphorylation. IL-6-induced increase of 2-DG uptake and GLUT-2 protein expression were blocked by JAK2-specific siRNA, a STAT3 inhibitor, staurosporine, and bisindolylmaleimide I (PKC inhibitors). In addition, IL-6 increased EGFR/src/FAK, PI3K/Akt phosphorylation and 2-DG uptake as well as GLUT-2 protein expression, which were blocked by AG 1478 (EGF receptor inhibitor), PP2 (src family of tyrosine kinase inhibitor), PI3K-specific siRNA, and a Akt inhibitor. Furthermore, IL-6 increased p44/42 MAPKs phosphorylation and p44 and p42 MAPK-specific siRNA mixture blocked IL-6-induced increase of 2-DG uptake and GLUT-2 protein expression. In conclusion, IL-6 stimulates the 2-DG uptake through p44/42 MAPKs activation via Ca(2+)/PKC and EGF receptor in primary cultured chicken hepatocytes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism*
  • Cells, Cultured
  • Chickens
  • Deoxyglucose / metabolism*
  • Enzyme Activation / drug effects
  • ErbB Receptors / metabolism*
  • Extracellular Signal-Regulated MAP Kinases / metabolism*
  • Hepatocytes / drug effects
  • Hepatocytes / enzymology*
  • Interleukin-6 / pharmacology*
  • Janus Kinases / metabolism
  • Male
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Mitogen-Activated Protein Kinase 3 / metabolism
  • Models, Biological
  • Protein Kinase C / metabolism*
  • Receptors, Interleukin-6 / metabolism
  • STAT Transcription Factors / metabolism

Substances

  • Interleukin-6
  • Receptors, Interleukin-6
  • STAT Transcription Factors
  • Deoxyglucose
  • ErbB Receptors
  • Janus Kinases
  • Protein Kinase C
  • Extracellular Signal-Regulated MAP Kinases
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • Calcium