The JAK2-Akt-glycogen synthase kinase-3β signaling pathway is involved in toll-like receptor 2-induced monocyte chemoattractant protein-1 regulation

Mol Med Rep. 2012 Apr;5(4):1063-7. doi: 10.3892/mmr.2012.741. Epub 2012 Jan 3.

Abstract

Monocyte chemoattractant protein-1 (MCP-1) is an essential cytokine for the migration of monocytes into vessels, and is also involved in the pathogenesis of atherosclerosis. In this study, we investigated the importance of janus kinase 2 (JAK2) and the function of the Akt and glycogen synthase kinase-3β (GSK3β) pathway in toll-like receptor (TLR2)-mediated MCP-1 expression. The TLR2 agonist, Pam3CSK4, induced MCP-1 expression in the Raw264.7 cell line. The induction of MCP-1 was seen in the bone marrow-derived macrophages of wild-type mice but not in TLR2 knockout mice. The TLR2-mediated MCP-1 induction was myeloid differentiation primary response gene 88 (MyD88)-independent. By contrast, the inactivation of JAK2 attenuated TLR2-mediated MCP-1 expression. The JAK inhibitor suppressed the phosphorylation of GSK3β as well as Akt by Pam3CSK4 stimulation. While the inactivation of Akt by LY294002 suppressed TLR2-mediated MCP-1 induction, the inactivation of GSK3β by LiCl potentiated TLR2-mediated MCP-1 induction. Furthermore, Akt inhibitor suppressed TLR2-mediated phosphorylation of GSK3β. Taken together, these results suggest that a MyD88-independent pathway exists in TLR2 signaling; the JAK2-Akt-GSK3β pathway is a novel MyD88-independent pathway for MCP-1 induction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Chemokine CCL2 / metabolism*
  • Chromones / pharmacology
  • Glycogen Synthase Kinase 3 / metabolism*
  • Glycogen Synthase Kinase 3 beta
  • Janus Kinase 2 / antagonists & inhibitors
  • Janus Kinase 2 / metabolism*
  • Lipopeptides / pharmacology
  • Lithium Chloride / pharmacology
  • Mice
  • Mice, Knockout
  • Morpholines / pharmacology
  • Myeloid Differentiation Factor 88 / metabolism
  • Phosphorylation
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Signal Transduction* / drug effects
  • Toll-Like Receptor 2 / agonists
  • Toll-Like Receptor 2 / genetics
  • Toll-Like Receptor 2 / metabolism*

Substances

  • Chemokine CCL2
  • Chromones
  • Lipopeptides
  • Morpholines
  • Myeloid Differentiation Factor 88
  • Pam2CSK4 lipopeptide
  • Toll-Like Receptor 2
  • 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one
  • Janus Kinase 2
  • Glycogen Synthase Kinase 3 beta
  • Gsk3b protein, mouse
  • Proto-Oncogene Proteins c-akt
  • Glycogen Synthase Kinase 3
  • Lithium Chloride