Effect of smoking on MAP kinase-induced modulation of IL-8 in human alveolar macrophages.
Inflammatory cytokine production by alveolar macrophages (AMs) is regulated by transcriptional activation and may be increased by cigarette smoking. The smoking-induced regulation of interleukin (IL)-8 by extracellular signal-regulated kinase (ERK)-1 and -2, p38 mitogen-activated protein kinase (MAPK) and the transcription factor nuclear factor-kappaB (NF-kappaB) in lipopolysaccharide-stimulated AMs was assessed in nine smokers compared with nine healthy nonsmokers. IL-8 production was dependent on phosphorylation of ERK-1 and -2 and p38 MAPK, as examined by PD 098059 (10 microM), an inhibitor of the upstream activator of MAPK kinase (MKK)-1, and SB 203580 (10 microM), an inhibitor of p38 MAPK. IL-8 release and the inhibitory effect of PD 098059 were increased in AMs from smokers. Moreover, ERK-2 messenger ribonucleic acid expression, as examined by reverse transcriptase polymerase chain reaction and phosphorylation of ERK-2 using Western blots, were increased in AMs from smokers, indicating a smoking-induced modulatory role of ERK-1 and -2. Lipopolysaccharide-induced IL-8 production was dependent on activation of NF-kappaB, as examined by SN 50 (100 microM), an inhibitor of NF-kappaB translocation, and the specific NF-kappaB inhibitor kinase-2 inhibitor, AS 602868 (10 microM), with no differences in AMs from smokers and nonsmokers. SN 50 but not PD 098059 and SB 203580 blocked NF-kappaB deoxyribonucleic acid-binding, and this occurred to the same extent in AMs from smokers and nonsmokers, as examined by electromobility shift assay. It is concluded that cigarette smoking enhances mitogen-activated protein kinase activation more than nuclear factor-kappaB activation to increase lipopolysaccharide-induced interleukin-8 production in alveolar macrophages.
Koch
A
A
Dept of Pneumology, Clinic III for Internal Medicine, University of Cologne, Cologne, Germany. andrea.koch@uni-koeln.de
Giembycz
M
M
Stirling
R G
RG
Lim
S
S
Adcock
I
I
Wassermann
K
K
Erdmann
E
E
Chung
K F
KF
D000328:Adult; D000704:Analysis of Variance; D001999:Bronchoscopy; D018929:Cell Culture Techniques; D005260:Female; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D016676:Macrophages, Alveolar / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D012907:Smoking; D048051:p38 Mitogen-Activated Protein Kinases
D016209:Interleukin-8; D008070:Lipopolysaccharides; D016328:NF-kappa B; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases