title: Coffee and Maillard products activate NF-kappaB in macrophages via H2O2 production.
abstract: In this study, we investigated the immunomodulatory activity of coffee and Maillard reaction products on macrophages in vitro. Stimulation of macrophages with coffee, but not with raw coffee extract in PBS, led to a 13-fold increased nuclear NF-kappaB translocation. A Maillard reaction mixture (25 mM D-ribose/L-lysine, 30 min at 120 degrees C) increased NF-kappaB translocation 18-fold (in PBS) or six-fold (in medium). MRPs also induced a two-fold increased NF-kappaB translocation in untransfected human embryonic kidney (HEK) cells as well as in HEK cells stably transfected with the receptor for advanced glycation endproducts (RAGE), indicating that the effect was not RAGE mediated. On the other hand, catalase totally abolished coffee- and MRP-induced NF-kappaB translocation. Consequently, up to 366 microM hydrogen peroxide was measured in the coffee preparation and Maillard mixtures used for cell stimulation. Stimulation of macrophages with MRPs did not lead to significantly increased IL-6 or NO release. Thus, it can be concluded that coffee and MRPs induce NF-kappaB translocation in macrophages via the generation of hydrogen peroxide.
authors.affiliation: Institute of Pharmacy and Food Chemistry, Friedrich-Alexander-University, Erlangen, Germany.
authors.forename: Sonja
authors.initials: S
authors.lastname: Muscat
authors.forename: Joana
authors.initials: J
authors.lastname: Pelka
authors.forename: Jörg
authors.initials: J
authors.lastname: Hegele
authors.forename: Bernd
authors.initials: B
authors.lastname: Weigle
authors.forename: Gerald
authors.initials: G
authors.lastname: Münch
authors.forename: Monika
authors.initials: M
authors.lastname: Pischetsrieder
mesh_terms: D000818:Animals; D002460:Cell Line; D003069:Coffee / Q000737:chemistry*; D004622:Embryo, Mammalian; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism*; D015850:Interleukin-6 / Q000378:metabolism; D007668:Kidney; D008239:Lysine / Q000494:pharmacology; D008264:Macrophages / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism; D015416:Maillard Reaction; D016328:NF-kappa B / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic / Q000235:genetics / Q000502:physiology; D012266:Ribose / Q000494:pharmacology; D014162:Transfection
chemical_list: D003069:Coffee; D015850:Interleukin-6; D016328:NF-kappa B; D017382:Reactive Oxygen Species; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic; D009569:Nitric Oxide; D012266:Ribose; D006861:Hydrogen Peroxide; D008239:Lysine