title: Nitric oxide up-regulates DNA-binding activity of nuclear factor-kappaB in macrophages stimulated with silica and inflammatory stimulants.
abstract: Nitric oxide (NO), a reactive nitrogen species, plays an important role in inflammatory lung damage. In the present study, we investigated the role of NO in DNA-binding activity of NF-kappaB in macrophages stimulated with silica or other inflammatory stimulants. Treatment of mouse macrophages (RAW264.7 cells) with a selective inhibitor of inducible nitric oxide synthase (iNOS), L-N6-(1-iminoethyl) lysine (L-NIL), or a nonselective iNOS inhibitor, N omega-nitro-L-arginine methylester (L-NAME), resulted in inhibition of silica-induced nitric oxide production as well as silica-induced NF-kappaB activation. L-NIL also effectively inhibited NF-kappaB activation induced by other inflammatory stimulants, such as lipopolysaccharide (LPS) or muramyl dipeptide (MDP). These inhibitory effects of L-NIL and L-NAME on silica- or LPS-induced NF-kappaB activation were also observed in primary rat alveolar macrophages. Furthermore, NO generating compounds, such as sodium nitroprusside (SNP) and 3-morpholinosydnonimine (SIN-1), caused a dose-dependent increase in NF-kappaB activation, which was positively correlated with the level of NO production. Specific inhibitors of protein tyrosine kinase, such as genistein and AG494, prevented NF-kappaB activation in SNP- or SIN-1 treated cells, suggesting involvement of tyrosine kinase in the NO signaling pathway leading to NF-kappaB activation. In contrast, inhibitors of protein kinase C or A, such as staurosporine or H89, had no inhibitory effect on SIN-1 induced NF-kappaB activation. Metalloporphyrins, such as tetrakis (N-methyl-4'-pyridyl) porphyrinato iron (III) (Fe-TMPyP) and Zn-TMPyP which are known to alter NO-dependent activity, markedly inhibited silica- and LPS-induced NF-kappaB activation. The results suggest that NF-kappaB activation in macrophages can be induced under certain conditions by nitric oxide and that nitric oxide produced by phagocytes exposed to inflammatory agents may up-regulate the activation of NF-kappaB.
authors.affiliation: Department of Physiology, College of Medicine, Ewha Medical Research Center and Center for Cell Signaling Research, Ewha Womans University, Seoul, Korea.
authors.forename: J L
authors.initials: JL
authors.lastname: Kang
authors.forename: K
authors.initials: K
authors.lastname: Lee
authors.forename: V
authors.initials: V
authors.lastname: Castranova
mesh_terms: D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000037:antagonists & inhibitors; D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004247:DNA / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019833:Genistein / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000037:antagonists & inhibitors / Q000378:metabolism; D008239:Lysine / Q000031:analogs & derivatives / Q000494:pharmacology; D008264:Macrophages / Q000378:metabolism*; D016676:Macrophages, Alveolar / Q000378:metabolism; D008297:Male; D051379:Mice; D008981:Molsidomine / Q000031:analogs & derivatives / Q000494:pharmacology; D016328:NF-kappa B / Q000378:metabolism*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism* / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D009573:Nitrites / Q000378:metabolism; D009599:Nitroprusside / Q000494:pharmacology; D010587:Phagocytosis; D011485:Protein Binding / Q000187:drug effects; D011493:Protein Kinase C / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D051381:Rats; D017207:Rats, Sprague-Dawley; D012822:Silicon Dioxide / Q000494:pharmacology*; D019311:Staurosporine / Q000494:pharmacology; D013449:Sulfonamides; D020032:Tyrphostins / Q000494:pharmacology; D015854:Up-Regulation
chemical_list: D000276:Adjuvants, Immunologic; D004791:Enzyme Inhibitors; D007546:Isoquinolines; D008070:Lipopolysaccharides; C090663:N(6)-(1-iminoethyl)lysine; D016328:NF-kappa B; D009573:Nitrites; D013449:Sulfonamides; D020032:Tyrphostins; C107502:AG 494; D009599:Nitroprusside; D009569:Nitric Oxide; D000119:Acetylmuramyl-Alanyl-Isoglutamine; C002385:linsidomine; D012822:Silicon Dioxide; D004247:DNA; D008981:Molsidomine; D019833:Genistein; D019001:Nitric Oxide Synthase; D011505:Protein-Tyrosine Kinases; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D019311:Staurosporine; D008239:Lysine; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide; D019331:NG-Nitroarginine Methyl Ester