title: Oxidative processes in human promonocytic cells (THP-1) after differentiation into macrophages by incubation with Chlamydia pneumoniae extracts.
abstract: Human monocytes differentiated into macrophages by Chlamydia pneumoniae were able to oxidize blood lipoproteins, as discovered by Kalayoglu et al. (1998). Using a model of human promonocytic cells (THP-1), the cells were differentiated into macrophages by preincubation with C. pneumoniae extract, and further stimulated by phorbol myristate acetate. In these conditions, the differentiated cells oxidized a thiol compound and released superoxide anion as demonstrated respectively by gas liquid chromatography and electron spin resonance. The thiol oxidation and superoxide anion release were inhibited by diphenyliodonium, a NADPH oxidase and NOsynthase inhibitor, proving that the respiratory burst and the NOsynthase were involved in the oxidation processes occurring in the differentiated THP-1. The role of H(2)O(2) (derived from superoxide anion) was indicated by the enhancing effect of a peroxidase on the thiol oxidation. The presence of alpha-tocopherol in the surrounding medium strongly diminished the oxidation of the thiol target.
authors.affiliation: Centre for Oxygen Research and Development, University of Liège, Institut de Chimie, B6a, Domaine Universitaire du Sart Tilman, Liège, 4000, Belgium. amouithys@ulg.ac.be
authors.forename: A
authors.initials: A
authors.lastname: Mouithys-Mickalad
authors.forename: G
authors.initials: G
authors.lastname: Deby-Dupont
authors.forename: M
authors.initials: M
authors.lastname: Nys
authors.forename: M
authors.initials: M
authors.lastname: Lamy
authors.forename: C
authors.initials: C
authors.lastname: Deby
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001713:Biphenyl Compounds / Q000494:pharmacology; D002273:Carcinogens; D002454:Cell Differentiation; D002460:Cell Line; D016993:Chlamydophila pneumoniae / Q000378:metabolism; D004578:Electron Spin Resonance Spectroscopy; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008264:Macrophages / Q000378:metabolism*; D008956:Models, Chemical; D009000:Monocytes / Q000378:metabolism*; D019255:NADPH Oxidases / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D009861:Onium Compounds / Q000494:pharmacology; D010100:Oxygen / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000378:metabolism; D013482:Superoxide Dismutase / Q000494:pharmacology; D013481:Superoxides / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate; D014527:Uric Acid / Q000494:pharmacology; D014810:Vitamin E / Q000378:metabolism / Q000494:pharmacology; D019323:omega-N-Methylarginine / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D001713:Biphenyl Compounds; D002273:Carcinogens; D004791:Enzyme Inhibitors; D009861:Onium Compounds; D013438:Sulfhydryl Compounds; C031291:diphenyliodonium; D013481:Superoxides; D014810:Vitamin E; D014527:Uric Acid; D019323:omega-N-Methylarginine; D006861:Hydrogen Peroxide; D019001:Nitric Oxide Synthase; D013482:Superoxide Dismutase; D019255:NADPH Oxidases; D013755:Tetradecanoylphorbol Acetate; D010100:Oxygen