类胰蛋白酶在ECV304细胞的炎症反应中激活蛋白激酶B。

Tryptase activates PKB in inflammatory reaction in ECV304 cells.

作者信息

Ma Yongjie, Zhang Bin, Qian Ruizhe, Lu Chao, Zhao Fengdi, Yin Lianhua

机构信息

Department of Physiology, Shanghai Medical College, Fudan University, 138# Yixueyuan Road, Shanghai 200032, PR China.

出版信息

Biochim Biophys Acta. 2006 Mar;1763(3):313-21. doi: 10.1016/j.bbamcr.2006.02.002. Epub 2006 Mar 6.

DOI:10.1016/j.bbamcr.2006.02.002

PMID:16564100

Abstract

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.

摘要

类胰蛋白酶参与蛋白酶激活受体-2（PAR-2）介导的白细胞介素-8（IL-8）表达上调。本报告显示了类胰蛋白酶对基因表达和激活的影响，包括上调IL-8表达。在类胰蛋白酶（1 ng/ml）处理后1小时，核因子κB（NF-κB）的mRNA表达首先增加，并在4小时后达到平台期。NF-κB的mRNA增加了3倍（n = 3，P < 0.05），激活蛋白-1（AP-1）增加了2倍（n = 3，P < 0.05），蛋白激酶B（PKB）增加了10倍（n = 3，P < 0.05）。然而，与对照细胞相比，在mRNA水平上，类胰蛋白酶处理不影响应激活化蛋白激酶（JNK）和p38丝裂原活化蛋白激酶（p38 MAPK）的表达。此外，除了增加p38 MAPK的磷酸化外，类胰蛋白酶处理还在处理后15分钟使PKB的磷酸化增加了2倍。类胰蛋白酶对PKB的上调和磷酸化作用可被10 microM的磷酸肌醇-3-激酶（PI3K）抑制剂（LY294002）或反义PKB cDNA转染消除。LY294002和反义PKB cDNA可抑制NF-κB表达的上调。这些结果表明，类胰蛋白酶可激活PI3K-PKB途径并增强IL-8表达。