Involvement of MAPKs, NF-κB and p300 co-activator in IL-1β-induced cytosolic phospholipase A2 expression in canine tracheal smooth muscle cells

Shue Fen Luo, Chih Chung Lin, Hsin Chieh Chen, Wei Ning Lin, I. Ta Lee, Chiang Wen Lee, Li Der Hsiao, Chuen Mao Yang

Research output: Contribution to journalArticlepeer-review

17 Citations (Scopus)

Abstract

Cytosolic phospholipase A2 (cPLA2) plays a pivotal role in mediating agonist-induced arachidonic acid release for prostaglandin (PG) synthesis during stimulation with interleukin-1β (IL-1β). However, the mechanisms underlying IL-1β-induced cPLA2 expression and PGE2 synthesis by canine tracheal smooth muscle cells (CTSMCs) have not been defined. IL-1β induced cPLA2 protein and mRNA expression, PGE2 production, and phosphorylation of p42/p44 MAPK, p38 MAPK (ATF2), and JNK (c-Jun) in a time- and concentration-dependent manner, determined by Western blotting, RT-PCR, and ELISA, which was attenuated by the inhibitors of MEK1/2 (U0126), p38 MAPK (SB202190), and JNK (SP600125), or transfection with dominant negative mutants of MEK1/2, p38, and JNK, respectively. Furthermore, IL-1β-induced cPLA2 expression and PGE2 synthesis was inhibited by a selective NF-κB inhibitor (helenalin) or transfection with dominant negative mutants of NF-κB inducing kinase (NIK), IκB kinase (IKK)-α, and IKK-β. Consistently, IL-1β stimulated both IκB-α degradation and NF-κB translocation into nucleus in these cells. NF-κB translocation was blocked by helenalin, but not by U0126, SB202190, and SP600125. MAPKs together with NF-κB-activated p300 recruited to cPLA2 promoter thus facilitating the binding of NF-κB to cPLA2 promoter region and expression of cPLA2 mRNA. IL-1β-induced cPLA2 expression and PGE2 production was inhibited by actinomycin D and cycloheximide, indicating the involvement of transcriptional and translational events in these responses. These results suggest that in CTSMCs, IL-1β-induced cPLA2 expression and PGE2 synthesis was independently mediated through activation of MAPKs and NF-κB pathways and was connected to p300 recruitment and activation.

Original languageEnglish
Pages (from-to)396-407
Number of pages12
JournalToxicology and Applied Pharmacology
Volume232
Issue number3
DOIs
Publication statusPublished - Nov 1 2008
Externally publishedYes

Keywords

  • cPLA
  • IL-1β
  • MAPKs
  • NF-κB
  • PGE

ASJC Scopus subject areas

  • Pharmacology
  • Toxicology

Fingerprint Dive into the research topics of 'Involvement of MAPKs, NF-κB and p300 co-activator in IL-1β-induced cytosolic phospholipase A2 expression in canine tracheal smooth muscle cells'. Together they form a unique fingerprint.

Cite this