Tryptase activates PKB in inflammatory reaction in ECV304 cells.
Tryptase is involved in proteinase-activated receptor-2 (PAR-2) mediated up-regulation of IL-8 expression. The present report showed the effects of tryptase on gene expression and activation, including up-regulation IL-8 expression. The expression of mRNA for NF-kappaB first increased at 1 h after tryptase-treatment (1 ng/ml) and reached the plateau after 4 h. The NF-kappaB mRNA increased by 3-fold (n = 3, P < 0.05), AP-1 by 2-fold (n = 3, P < 0.05), and PKB by 10-fold (n = 3, P < 0.05). However, tryptase-treatment did not affect the expression of JNK and p38 MAPK when compared with control cells at mRNA level. Furthermore, in addition to increasing phosphorylation of p38 MAPK, tryptase-treatment also increased phosphorylation of PKB by 2-fold at 15 min following the treatment. The up-regulation and phosphorylation of PKB by tryptase could be abolished by either phosphoinositol-3-kinase (PI3K) inhibitor (LY294002) at 10 microM or antisense PKB cDNA transfection. The up-regulation of NF-kappaB expression could be inhibited by LY294002 and antisense PKB cDNA. These results indicate that tryptase can activate PI3K-PKB pathway and enhance IL-8 expression.
Department of Physiology, Shanghai Medical College, Fudan University, 138# Yixueyuan Road, Shanghai 200032, PR China.
Yongjie
Y
Ma
Bin
B
Zhang
Ruizhe
R
Qian
Chao
C
Lu
Fengdi
F
Zhao
Lianhua
L
Yin
D002478:Cells, Cultured; D004789:Enzyme Activation / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007249:Inflammation / Q000201:enzymology* / Q000276:immunology; D016209:Interleukin-8 / Q000235:genetics; D016328:NF-kappa B / Q000235:genetics; D010766:Phosphorylation / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D044464:Receptor, PAR-2 / Q000235:genetics; D012697:Serine Endopeptidases / Q000494:pharmacology*; D013997:Time Factors; D018808:Transcription Factor AP-1 / Q000235:genetics; D053802:Tryptases; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
D016209:Interleukin-8; D016328:NF-kappa B; D012333:RNA, Messenger; D044464:Receptor, PAR-2; D018808:Transcription Factor AP-1; D051057:Proto-Oncogene Proteins c-akt; D048051:p38 Mitogen-Activated Protein Kinases; D012697:Serine Endopeptidases; D053802:Tryptases