Involvement of p42/p44 MAPK, JNK, and NF-kappaB in IL-1beta-induced ICAM-1 expression in human pulmonary epithelial cells.
Interleukin-1beta (IL-1beta) has been shown to induce the expression of intercellular adhesion molecule-1 (ICAM-1) on airway epithelial cells and contributes to inflammatory responses. However, the mechanisms regulating ICAM-1 expression by IL-1beta in human A549 cells was not completely understood. Here, the roles of mitogen-activated protein kinases (MAPKs) and NF-kappaB pathways for IL-1beta-induced ICAM-1 expression were investigated in A549 cells. IL-1beta induced expression of ICAM-1 protein and mRNA in a time- and concentration-dependent manner. The IL-1beta induction of ICAM-1 mRNA and protein were partially inhibited by U0126 and PD98059 (specific inhibitors of MEK1/2) and SP600125 [a specific inhibitor of c-Jun-N-terminal kinase (JNK)]. U0126 was more potent than other inhibitors to attenuate IL-1beta-induced ICAM-1 expression. Consistently, IL-1beta stimulated phosphorylation of p42/p44 MAPK and JNK which was attenuated by pretreatment with U0126 or SP600125, respectively. Moreover, transfection with dominant negative mutants of MEK1/2 (MEK K97R) or ERK2 (ERK2 K52R) also attenuated IL-1beta-induced ICAM-1 expression. The combination of PD98059 and SP600125 displayed an additive effect on IL-1beta-induced ICAM-1 gene expression. IL-1beta-induced ICAM-1 expression was almost completely blocked by a specific NF-kappaB inhibitor helenalin. Consistently, IL-1beta stimulated translocation of NF-kappaB into the nucleus and degradation of IkappaB-alpha which was blocked by helenalin, U0126, or SP600125. Taken together, these results suggest that activation of p42/p44 MAPK and JNK cascades, at least in part, mediated through NF-kappaB pathway is essential for IL-1beta-induced ICAM-1 gene expression in A549 cells. These results provide new insight into the mechanisms of IL-1beta action that cytokines may promote inflammatory responses in the airway disease.
Lin
Feng-Shu
FS
Graduate Institute of Natural Products, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan.
Lin
Chih-Chung
CC
Chien
Chin-Sung
CS
Luo
Shu-Feng
SF
Yang
Chuen-Mao
CM
D045744:Cell Line, Tumor; D004357:Drug Synergism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004847:Epithelial Cells / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D007375:Interleukin-1 / Q000494:pharmacology*; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010766:Phosphorylation; D011650:Pulmonary Alveoli / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism; D012717:Sesquiterpenes / Q000494:pharmacology; D045789:Sesquiterpenes, Guaiane
D004791:Enzyme Inhibitors; D007375:Interleukin-1; D016328:NF-kappa B; D012333:RNA, Messenger; D012717:Sesquiterpenes; D045789:Sesquiterpenes, Guaiane; D018799:Intercellular Adhesion Molecule-1; C001329:helenalin; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases