TY - JOUR A1 - Banning, Anja A1 - Deubel, S. A1 - Kluth, Dirk A1 - Zhou, Z. W. A1 - Brigelius-Flohé, Regina T1 - The GI-GPx gene is a target for Nrf2 N2 - The gastrointestinal glutathione peroxidase (GI-GPx, GPx2) is a selenoprotein that was suggested to act as barrier against hydroperoxide absorption but has also been implicated in the control of inflammation and malignant growth. In CaCo-2 cells, GI-GPx was induced by t-butyl hydroquinone (tBHQ) and sulforaphane (SFN), i.e., "antioxidants" known to activate the "antioxidant response element" (ARE) via electrophilic thiol modification of Keap1 in the Nrf2/ Keap1 system. The functional significance of a putative ARE in the GI-GPx promoter was validated by transcriptional activation of reporter gene constructs upon exposure to electrophiles (tBHQ, SFN, and curcumin) or overexpression of Nrf2 and by reversal of these effects by mutation of the ARE in the promoter and by overexpressed Keap1. Binding of Nrf2 to the ARE sequence in authentic gpx2 was corroborated by chromatin immunoprecipitation. Thus, the presumed natural antioxidants sulforaphane and curcumin may exert their anti-inflammatory and anticarcinogenic effects not only by induction of phase 2 enzymes but also by the up-regulation of the selenoprotein GI-GPx Y1 - 2005 SN - 0270-7306 ER - TY - JOUR A1 - Brigelius-Flohé, Regina A1 - Banning, Anja A1 - Kny, M. A1 - Böl, Gaby Fleur T1 - Redox events in interleukin-1 signaling N2 - There is increasing evidence that reactive oxygen species (ROS) are mediators in growth factor and cytokine signaling pathways. Mechanisms by which ROS can interfere with signaling cascades may include regulation of protein activities by the modification of essential cysteines. Modification can be performed chemically or enzyme-catalyzed. Enzymes catalyzing a reversible thiol modification within proteins are to be able to react with both, ROS and protein thiols. If hydroperoxides are involved, promising candidates are peroxiredoxins and glutathione peroxidases (GPx), especially the phospholipid hydroperoxide GPx. Interleukin-1, one of the key players in inflammatory response, stimulates the production of ROS itself, but its signaling cascade can also be influenced by ROS and by thiol modifying agents. Targets are located in early, intermediate, and late events in the signaling cascade. We here summarize what is known about the effects of thiol modifying agents, selenium and glutathione peroxidases, on the assembly of the IL-1 receptor signaling complex as an early event, on the activation of NF-kappaB as an intermediate event, and on the expression of cell adhesion molecules as a late event in IL-1 signaling. (C) 2003 Elsevier Inc. All rights reserved Y1 - 2004 SN - 0003-9861 ER - TY - JOUR A1 - Böl, Gaby Fleur A1 - Jurrmann, Nadine A1 - Brigelius-Flohé, Regina T1 - Cellular trafficking of the IL-1RI-associated kinase-1 requires intact kinase activity N2 - Upon stimulation of cells with interleukin-1 (IL-1) the IL-1 receptor type 1 (IL-1RI) associated kinase-1 (IRAK- 1) transiently associates to and dissociates front the IL-IRI and thereafter translocates into the nucleus. Here we show that nuclear translocation of IRAK-I depends on its kinase activity since translocation was not observed in EL-4 cells overexpressing a kinase negative IRAK-1 mutant (EL-4(IRAK-1-K239S)). IRAK-1 itself, an endogenous substrate with an apparent molecular weight of 24 kDa (p24). and exogenous substrates like histone and myelin basic protein are phosphorylated by nuclear located IRAK-1. Phosphorylation of p24 cannot be detected in EL-4(IRAK-1-K239S) cells. IL-1- dependent recruitment of IRAK-1 to the IL-1RI and subsequent phosphorylation of IRAK-l is a prerequisite for nuclear translocation of IRAK-1. It is therefore concluded that intracellular localization of IRAK-1 depends on its kinase activity and that IRAK-1 may also function as a kinase in the nucleus as shown by a new putative endogenous substrate. (c) 2005 Elsevier Inc. All rights reserved Y1 - 2005 SN - 0006-291X ER - TY - JOUR A1 - Jurrmann, Nadine A1 - Brigelius-Flohé, Regina A1 - Böl, Gaby Fleur T1 - Curcumin blocks interleukin-1 (IL-1) signaling by inhibiting the recruitment of the IL-1 receptor-associated kinase IRAK in murine thymoma EL-4 cells N2 - Curcumin is a dietary compound with diverse anti-inflammatory and anticarcinogenic effects in several experimental models. A mechanism by which curcumin exerts these actions might be the direct modification of protein thiols, thereby altering the activity of the affected proteins. An early event in inflammatory signaling cascades is the recruitment of the interleukin-1 (IL-1) receptor-associated kinase (IRAK) to the IL-1 receptor (IL-1 RI) upon stimulation with IL-1. IRAK recruitment was shown recently to be inhibited by agents that modify thiols of IRAK. We asked, therefore, whether IRAK is also a target for curcumin. Curcumin indeed blocked IRAK thiols in a murine T-cell line stably overexpressing IRAK (EL-4(IRAK)), which resulted in the inhibition of IRAK recruitment to the IL-1RI and phosphorylation of IRAK and IL-1RI-associated proteins. Inhibitory effects were not reversible by thiol-reducing agents. Thus, modification by curcumin did not occur by oxidation but rather by alkylation, as is typical for electrophilic compounds reacting as Michael addition acceptors. The block in one of the earliest events in the IL-1 signaling cascade can explain the often observed inhibition of IL-1-mediated signaling steps by curcumin further downstream. Hence, thiol modification might be a crucial step in the anti-inflammatory functions of curcumin Y1 - 2005 SN - 0022-3166 ER - TY - JOUR A1 - Lehmann, Claudia A1 - Wollenberger, Ursula A1 - Brigelius-Flohé, Regina A1 - Scheller, Frieder W. T1 - Bioelectrocatalysis by a selenoenzyme Y1 - 1998 ER - TY - JOUR A1 - Lehmann, Claudia A1 - Wollenberger, Ursula A1 - Brigelius-Flohé, Regina A1 - Scheller, Frieder W. T1 - Modified gold electrodes for electrochemical studies of the reaction phospholipid hydroperoxide glutathione peroxidas with glutathione and glutathione disulfide Y1 - 2001 ER - TY - JOUR A1 - Lisdat, Fred A1 - Utepbergenov, D. A1 - Haseloff, R. F. A1 - Blasig, Ingolf E. A1 - Stöcklein, Walter F. M. A1 - Scheller, Frieder W. A1 - Brigelius-Flohé, Regina T1 - An optical method for the detection of oxidative stress using protein-RNA interaction Y1 - 2001 ER - TY - JOUR A1 - Song, Hui A1 - Bergstrasser, Claudia A1 - Rafat, Neysan A1 - Hoeger, Simone A1 - Schmidt, Marc A1 - Endres, N. A1 - Goebeler, Matthias A1 - Hillebrands, Jan-Luuk A1 - Brigelius-Flohé, Regina A1 - Banning, Antje A1 - Beck, Grietje A1 - Loesel, Ralf A1 - Yard, Benito A. T1 - The carbon monoxide releasing molecule (CORM-3) inhibits expression of vascular cell adhesion molecule-1 and E- selectin independently of haem oxygenase-1 expression N2 - Background and purpose: Although carbon monoxide (CO) can modulate inflammatory processes, the influence of CO on adhesion molecules is less clear. This might be due to the limited amount of CO generated by haem degradation. We therefore tested the ability of a CO releasing molecule (CORM-3), used in supra-physiological concentrations, to modulate the expression of vascular cell adhesion molecule (VCAM)-1 and E-selectin on endothelial cells and the mechanism(s) involved. Experimental approach: Human umbilical vein endothelial cells (HUVECs) were stimulated with tumour necrosis factor (TNF)-alpha in the presence or absence of CORM-3. The influence of CORM-3 on VCAM-1 and E- selectin expression and the nuclear factor (NF)-kappa B pathway was assessed by flow cytometry, Western blotting and electrophoretic mobility shift assay. Key results: CORM-3 inhibited the expression of VCAM-1 and E-selectin on TNF-alpha- stimulated HUVEC. VCAM-1 expression was also inhibited when CORM-3 was added 24 h after TNF-alpha stimulation or when TNF-alpha was removed. This was paralleled by deactivation of NF-kappa B and a reduction in VCAM-1 mRNA. Although TNF- alpha removal was more effective in this regard, VCAM-1 protein was down-regulated more rapidly when CORM-3 was added. CORM-3 induced haem oxygenase-1 (HO-1) in a dose- and time-dependent manner, mediated by the transcription factor, Nrf2. CORM-3 was still able to down-regulate VCAM-1 expression in HUVEC transfected with siRNA for HO-1 or Nrf2. Conclusions and implications: Down-regulation of VCAM and E-selectin expression induced by CORM-3 was independent of HO-1 up- regulation and was predominantly due to inhibition of sustained NF-kappa B activation. Y1 - 2009 UR - http://www3.interscience.wiley.com/journal/121548564/home U6 - https://doi.org/10.1111/j.1476-5381.2009.00215.x SN - 0007-1188 ER - TY - CHAP A1 - Wiesner, Melanie A1 - Barknowitz, Gitte A1 - Florian, Simone A1 - Haack, Michael A1 - Lehmann, Carsten A1 - Lippmann, Doris A1 - Mewis, Inga A1 - Schumacher, Fabian A1 - Brigelius-Flohé, Regina A1 - Schreiner, Monika A1 - Glatt, Hansruedi T1 - Pak Choi Fed to Mice: Formation of DNA Adducts and Influence on Xenobiotic-Metabolizing Enzymes T2 - NAUNYN-SCHMIEDEBERGS ARCHIVES OF PHARMACOLOGY Y1 - 2015 SN - 0028-1298 SN - 1432-1912 VL - 388 SP - S68 EP - S68 PB - Springer CY - New York ER -