IL-17 enhances IL-1beta-mediated CXCL-8 release from human airway smooth muscle cells

Am J Physiol Lung Cell Mol Physiol. 2007 Apr;292(4):L1023-9. doi: 10.1152/ajplung.00306.2006. Epub 2006 Dec 22.

Abstract

Recent studies into the pathogenesis of airway disorders such as asthma have revealed a dynamic role for airway smooth muscle cells in the perpetuation of airway inflammation via secretion of cytokines and chemokines. In this study, we evaluated whether IL-17 could enhance IL-1beta-mediated CXCL-8 release from human airway smooth muscle cells (HASMC) and investigated the upstream and downstream signaling events regulating the induction of CXCL-8. CXCL-8 mRNA and protein induction were assessed by real-time RT-PCR and ELISA from primary HASMC cultures. HASMC transfected with site-mutated activator protein (AP)-1/NF-kappaB CXCL-8 promoter constructs were treated with selective p38, MEK1/2, and phosphatidylinositol 3-kinase (PI3K) inhibitors to determine the importance of MAPK and PI3K signaling pathways as well as AP-1 and NF-kappaB promoter binding sites. We demonstrate IL-17 induced and synergized with IL-1beta to upregulate CXCL-8 mRNA and protein levels. Erk1/2 and p38 modulated IL-17 and IL-1beta CXCL-8 promoter activity; however, IL-1beta also activated the PI3K pathway. The synergistic response mediating CXCL-8 promoter activity was dependent on both MAPK and PI3K signal transduction pathways and required the cooperation of AP-1 and NF-kappaB cis-acting elements upstream of the CXCL-8 gene. Collectively, our observations indicate MAPK and PI3K pathways regulate the synergy of IL-17 and IL-1beta to enhance CXCL-8 promoter activity, mRNA induction, and protein synthesis in HASMC via the cooperative activation of AP-1 and NF-kappaB trans-acting elements.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Humans
  • Interleukin-17 / physiology*
  • Interleukin-1beta / physiology*
  • Interleukin-8 / metabolism*
  • Mitogen-Activated Protein Kinase 1 / physiology
  • Mitogen-Activated Protein Kinase 3 / physiology
  • Muscle, Smooth / cytology
  • Muscle, Smooth / drug effects
  • Muscle, Smooth / metabolism*
  • NF-kappa B / physiology
  • Phosphatidylinositol 3-Kinases / physiology
  • Transcription Factor AP-1 / physiology
  • p38 Mitogen-Activated Protein Kinases / physiology

Substances

  • CXCL8 protein, human
  • Interleukin-17
  • Interleukin-1beta
  • Interleukin-8
  • NF-kappa B
  • Transcription Factor AP-1
  • Phosphatidylinositol 3-Kinases
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • p38 Mitogen-Activated Protein Kinases