title: Hydrogen peroxide induces murine macrophage chemokine gene transcription via extracellular signal-regulated kinase- and cyclic adenosine 5'-monophosphate (cAMP)-dependent pathways: involvement of NF-kappa B, activator protein 1, and cAMP response element binding protein.
abstract: Hydrogen peroxide (H(2)O(2)) has been shown to act as a second messenger that activates chemokine expression. In the present study, we investigated the mechanisms underlying this cellular regulation in the murine macrophage cell line B10R. We report that H(2)O(2) increases mRNA expression of various chemokines, macrophage-inflammatory protein (MIP)-1alpha/CC chemokine ligand (CCL)3, MIP-1beta/CCL4, MIP-2/CXC chemokine ligand 2, and monocyte chemoattractant protein-1/CCL2, by activating the extracellular signal-regulated kinase (ERK) pathway and the nuclear translocation of the transcription factors NF-kappaB, AP-1, and CREB. Blockage of the ERK pathway with specific inhibitors against mitogen-activated protein kinase kinase 1/2 and ERK1/ERK2 completely abolished both the H(2)O(2)-mediated chemokine up-regulation and the activation of all NF studied. Similarly, selective inhibition of cAMP and NF-kappaB strongly down-regulated the induction of all chemokine transcripts as well as CREB and NF-kappaB activation, respectively. Of interest, we detected a significant decrease of NF-kappaB, AP-1, and CREB DNA binding activities by reciprocal competition for these binding sites when either specific cold oligonucleotides (NF-kappaB, AP-1, and CREB) or Abs against various transcription factor subunits (p50, p65, c-Fos, Jun B, c-Jun, and CREB-1) were added. These findings indicate that cooperation between ERK- and cAMP-dependent pathways seems to be required to achieve the formation of an essential transcriptional factor complex for maximal H(2)O(2)-dependent chemokine modulation. Finally, experiments performed with actinomycin D suggest that H(2)O(2)-mediated MIP-1beta mRNA up-regulation results from transcriptional control, whereas that of MIP-1alpha, MIP-2, and monocyte chemoattractant protein-1 is due to both gene transcription activation and mRNA posttranscriptional stabilization.
authors.affiliation: Centre de Recherche en Infectiologie, Centre Hospitalier Universitaire de Québec, Pavillon du Centre Hospitalier de l'Université Laval, and Département de Biologie Médicale, Faculté de Médecine, Université Laval, Ste-Foy, Québec, Canada.
authors.forename: Maritza
authors.initials: M
authors.lastname: Jaramillo
authors.forename: Martin
authors.initials: M
authors.lastname: Olivier
mesh_terms: D000818:Animals; D002460:Cell Line; D018925:Chemokines / Q000096:biosynthesis / Q000235:genetics*; D000242:Cyclic AMP / Q000502:physiology*; D017362:Cyclic AMP Response Element-Binding Protein / Q000502:physiology; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000276:immunology*; D008264:Macrophages / Q000201:enzymology / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D008805:Mice, Inbred A; D008810:Mice, Inbred C57BL; D020928:Mitogen-Activated Protein Kinases / Q000502:physiology*; D016328:NF-kappa B / Q000502:physiology; D052002:NF-kappa B p50 Subunit; D012323:RNA Processing, Post-Transcriptional / Q000187:drug effects / Q000276:immunology; D012333:RNA, Messenger / Q000096:biosynthesis; D015534:Trans-Activators / Q000378:metabolism / Q000502:physiology*; D018808:Transcription Factor AP-1 / Q000502:physiology; D051996:Transcription Factor RelA; D014158:Transcription, Genetic / Q000187:drug effects / Q000276:immunology; D015854:Up-Regulation / Q000187:drug effects / Q000276:immunology
chemical_list: D018925:Chemokines; D017362:Cyclic AMP Response Element-Binding Protein; D016328:NF-kappa B; D052002:NF-kappa B p50 Subunit; D012333:RNA, Messenger; D015534:Trans-Activators; D018808:Transcription Factor AP-1; D051996:Transcription Factor RelA; D006861:Hydrogen Peroxide; D000242:Cyclic AMP; D020928:Mitogen-Activated Protein Kinases