title: Selected contribution: synergism between TNF-alpha and IL-1 beta in airway smooth muscle cells: implications for beta-adrenergic responsiveness.
abstract: In human cultured airway smooth muscle cells, interleukin (IL)-1 beta increases cyclooxygenase (COX)-2 expression and PGE(2) release, ultimately resulting in decreased beta-adrenergic responsiveness. In this study, we aimed to determine whether tumor necrosis factor-alpha (TNF-alpha) synergizes with IL-1 beta in the induction of these events. TNF-alpha alone, at concentrations up to 10 ng/ml, had no effect on COX-2 protein expression; at concentrations as low as 0.1 ng/ml, it significantly enhanced the ability of IL-1 beta (0.2 ng/ml) to induce COX-2 and to increase PGE(2) release. IL-1 beta and TNF-alpha in combination also significantly enhanced COX-2 promoter activity, indicating that synergism between the cytokines is mediated at the level of gene transcription. Although IL-1 beta and TNF-alpha each increased nuclear factor-kappa B activation and induced extracellular regulated kinase and p38 phosphorylation, combined administration of the cytokines did not enhance either nuclear factor-kappa B or mitogen-activated protein kinase activation. Combined administration of IL-1 beta (0.2 ng/ml) and TNF-alpha (0.1 or 1.0 ng/ml) reduced the ability of isoproterenol to decrease human airway smooth muscle cell stiffness, as measured by magnetic twisting cytometry, even though individually these cytokines, at these concentrations, had no effect on isoproterenol responses. Treatment with the selective COX-2 inhibitor NS-398 abolished the synergistic effects of TNF-alpha and IL-1 beta on beta-adrenergic responsiveness. Our results indicate that low concentrations of IL-1 beta and TNF-alpha synergize to promote beta-adrenergic hyporesponsiveness and that effects on COX-2 expression and PGE(2) are responsible for these events. The data suggest that the simultaneous release in the airway, of even very small amounts of cytokines, can have important functional consequences.
authors.affiliation: Physiology Program, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
authors.forename: P E
authors.initials: PE
authors.lastname: Moore
authors.forename: T
authors.initials: T
authors.lastname: Lahiri
authors.forename: J D
authors.initials: JD
authors.lastname: Laporte
authors.forename: T
authors.initials: T
authors.lastname: Church
authors.forename: R A
authors.initials: RA
authors.lastname: Panettieri
authors.forename: S A
authors.initials: SA
authors.lastname: Shore
mesh_terms: D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002478:Cells, Cultured; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D015232:Dinoprostone / Q000378:metabolism; D004357:Drug Synergism; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D007545:Isoproterenol / Q000494:pharmacology; D008280:Magnetics; D008565:Membrane Proteins; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009130:Muscle, Smooth / Q000166:cytology / Q000378:metabolism*; D009578:Nitrobenzenes / Q000494:pharmacology; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics / Q000378:metabolism; D011943:Receptors, Adrenergic, beta / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D013449:Sulfonamides / Q000494:pharmacology; D014132:Trachea / Q000166:cytology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D000318:Adrenergic beta-Agonists; D000970:Antineoplastic Agents; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D007375:Interleukin-1; D007527:Isoenzymes; D008565:Membrane Proteins; D009578:Nitrobenzenes; D011943:Receptors, Adrenergic, beta; D013449:Sulfonamides; D014409:Tumor Necrosis Factor-alpha; C080955:N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D015232:Dinoprostone; D007545:Isoproterenol