German cockroach proteases regulate interleukin-8 expression via nuclear factor for interleukin-6 in human bronchial epithelial cells.
German cockroach extract synergistically regulates tumor necrosis factor-alpha (TNF-alpha)-induced interleukin (IL)-8 expression in human airway epithelial cells. The IL-8 promoter contains nuclear factor (NF)-kappaB, activating protein (AP)-1, and NF for IL-6 (NF-IL6) transcription factor binding regions. Because cockroach extract activates extracellular regulated kinase (ERK), a known activator of AP-1 and NF-IL6, we focused on the regulation of these transcription factors. Although TNF-alpha and cockroach extract both increased AP-1 translocation, mutation of the AP-1 site in the context of the wild-type promoter had no effect on cockroach extract-induced synergy. Mutation of the NF-IL6 site in the context of the wild-type IL-8 promoter, or overexpression of a dominant-negative NF-IL6 mutant, each abolished cockroach extract-induced synergy. Cockroach extract induced NF-IL6 translocation and DNA binding, an effect that was further increased in the presence of TNF-alpha. Cockroach extract-induced regulation of NF-IL6 was due to active serine proteases in the extract as well as activation of protease activated receptor (PAR)-2, but not PAR-1. Chemical inhibition of ERK also attenuated cockroach extract-induced NF-IL6-DNA binding. We conclude that proteases in German cockroach extract regulate PAR-2 and ERK to increase NF-IL6 activity and synergistically regulate TNF-alpha-induced IL-8 promoter activity in human airway epithelium.
Page
Kristen
K
Division of Critical Care Medicine, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, ML7006, Cincinnati, OH 45229, USA. kristen.page@chmcc.org
Hughes
Valerie S
VS
Odoms
Kelli K
KK
Dunsmore
Katherine E
KE
Hershenson
Marc B
MB
D000818:Animals; D020048:Blattellidae / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D001980:Bronchi / Q000378:metabolism; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D016209:Interleukin-8 / Q000235:genetics* / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D010447:Peptide Hydrolases / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D021381:Protein Transport / Q000502:physiology; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D022782:CCAAT-Enhancer-Binding Protein-beta; D016209:Interleukin-8; D016328:NF-kappa B; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha; D048049:Extracellular Signal-Regulated MAP Kinases; D010447:Peptide Hydrolases