Cytokine upregulation of proteinase-activated-receptors 2 and 4 expression mediated by p38 MAP kinase and inhibitory kappa B kinase beta in human endothelial cells

Br J Pharmacol. 2007 Apr;150(8):1044-54. doi: 10.1038/sj.bjp.0707150. Epub 2007 Mar 5.


Background and purpose: Up-regulation of proteinase-activated receptor-2 (PAR2) is a factor in a number of disease states and we have therefore examined the signalling pathways involved in the expression of the receptor.

Experimental approach: We investigated the effects of tumour necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), trypsin and the PAR2 activating peptide, 2-furoyl(2f)-LIGKV-OH on both mRNA and functional expression of PAR2 in human umbilical vein endothelial cells (HUVECs). The effect of specific chemical inhibitors and dominant negative adenovirus constructs of the mitogen-activated protein kinase (MAPK) cascade and the nuclear factor kappa B (NF-kappaB) signalling pathway was assessed. Methods included semi-quantitative and quantitative RT-PCR, [(3)H]inositol phosphate (IP) accumulation and Ca(2+)-dependent fluorescence.

Key results: The above agonists induced both mRNA and functional expression of PAR2; PAR4 mRNA, but not that for PAR1 or PAR-3, also increased following TNFalpha treatment. Inhibition of p38 MAP kinase reduced PAR2 and PAR4 expression, whilst inhibition of MEK1/ERK/JNK was without effect. A similar dependency upon p38 MAP kinase was observed for the expression of PAR4. TNFalpha -induced enhancement of PAR2 stimulated [(3)H]-inositol phosphate accumulation (IP) and Ca(2+) signalling was abolished following SB203580 pre-treatment. Infection with adenovirus encoding dominant-negative IKKbeta (Ad.IKKbeta(+/-)) and to a lesser extent dominant-negative IKKalpha (Ad.IKKalpha(+/-)), substantially reduced both control and IL-1beta- induced expression of both PAR2 and PAR4 mRNA and enhancement of PAR2-stimulated IP accumulation and Ca(2+) mobilisation.

Conclusions and implications: These data reveal for the first time the signalling events involved in the upregulation of both PAR2 and PAR4 during pro-inflammatory challenge.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / genetics
  • Calcium Signaling / drug effects
  • Cells, Cultured
  • Cytokines / physiology*
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism*
  • Genes, Dominant
  • Humans
  • I-kappa B Kinase / genetics
  • I-kappa B Kinase / metabolism*
  • Imidazoles / pharmacology
  • Inositol Phosphates / metabolism
  • Interleukin-1beta / physiology
  • MAP Kinase Signaling System* / drug effects
  • Oligopeptides / pharmacology
  • Protein Kinase Inhibitors / pharmacology
  • Pyridines / pharmacology
  • RNA, Messenger / biosynthesis
  • Receptor, PAR-2 / biosynthesis*
  • Receptor, PAR-2 / genetics
  • Receptors, Thrombin / biosynthesis*
  • Receptors, Thrombin / genetics
  • Time Factors
  • Trypsin / pharmacology
  • Tumor Necrosis Factor-alpha / physiology
  • Up-Regulation / drug effects
  • p38 Mitogen-Activated Protein Kinases / metabolism*


  • 2-furoyl-leucyl-isoleucyl-glycyl-lysyl-valine
  • Cytokines
  • Imidazoles
  • Inositol Phosphates
  • Interleukin-1beta
  • Oligopeptides
  • Protein Kinase Inhibitors
  • Pyridines
  • RNA, Messenger
  • Receptor, PAR-2
  • Receptors, Thrombin
  • Tumor Necrosis Factor-alpha
  • I-kappa B Kinase
  • p38 Mitogen-Activated Protein Kinases
  • Trypsin
  • protease-activated receptor 4
  • SB 203580