HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Data Supplement A correction has been published Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by de Oliveira-Marques, V. Articles by Antunes, F. Search for Related Content PubMed PubMed Citation Articles by de Oliveira-Marques, V. Articles by Antunes, F. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB HYDROGEN PEROXIDE

A Quantitative Study of NF-B Activation by H₂O₂: Relevance in Inflammation and Synergy with TNF-¹

Virgínia de Oliveira-Marques^2,*, Luísa Cyrne^*,, H. Susana Marinho^*, and Fernando Antunes^*,,,

^* Grupo de Bioquímica dos Oxidantes e Antioxidantes, Centro de Química e Bioquímica and Departamento de Química e Bioquímica da Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal; Instituto de Investigação Científica Bento da Rocha Cabral, Lisboa, Portugal; and Computational Biology Services, Lisboa, Portugal

Although the germicide role of H₂O₂ released during inflammation is well established, a hypothetical regulatory function, either promoting or inhibiting inflammation, is still controversial. In particular, after 15 years of highly contradictory results it remains uncertain whether H₂O₂ by itself activates NF-B or if it stimulates or inhibits the activation of NF-B by proinflammatory mediators. We investigated the role of H₂O₂ in NF-B activation using, for the first time, a calibrated and controlled method of H₂O₂ delivery—the steady-state titration—in which cells are exposed to constant, low, and known concentrations of H₂O₂. This technique contrasts with previously applied techniques, which disrupt cellular redox homeostasis and/or introduce uncertainties in the actual H₂O₂ concentration to which cells are exposed. In both MCF-7 and HeLa cells, H₂O₂ at extracellular concentrations up to 25 µM did not induce significantly per se NF-B translocation to the nucleus, but it stimulated the translocation induced by TNF-. For higher H₂O₂ doses this stimulatory role shifts to an inhibition, which may explain published contradictory results. The stimulatory role was confirmed by the observation that 12.5 µM H₂O₂, a concentration found during inflammation, increased the expression of several proinflammatory NF-B-dependent genes induced by TNF- (e.g., IL-8, MCP-1, TLR2, and TNF-). The same low H₂O₂ concentration also induced the anti-inflammatory gene coding for heme oxygenase-1 (HO-1) and IL-6. We propose that H₂O₂ has a fine-tuning regulatory role, comprising both a proinflammatory control loop that increases pathogen removal and an anti-inflammatory control loop, which avoids an exacerbated harmful inflammatory response.

The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

¹ This work supported by Grant POCTI/BCI/42245/2001 from Fundação para a Ciência e a Technologia-Portugal. V.d.O.M. and F.A. acknowledge fellowships BD/16681/2004 and BPD/11487/2002 from Fundação para a Ciência e a Technologia-Portugal.

² Address correspondence and reprint requests to Dr. Virgínia de Oliveira-Marques, Centro de Química e Bioquímica, Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal. E-mail address: vmmarques{at}fc.ul.pt

³ Abbreviations used in this paper: ROS, reactive oxygen species; Egr-1, early growth response-1; H₂O₂, hydrogen peroxide; [H₂O₂]_ss, H₂O₂ steady-state concentration; HO-1, heme oxygenase-1; GPR89, G-protein-coupled receptor 89.

⁴ The online version of this article contains supplemental material.

This article has been cited by other articles:

				R. Lotfi, G. I. Herzog, R. A. DeMarco, D. Beer-Stolz, J. J. Lee, A. Rubartelli, H. Schrezenmeier, and M. T. Lotze Eosinophils Oxidize Damage-Associated Molecular Pattern Molecules Derived from Stressed Cells J. Immunol., October 15, 2009; 183(8): 5023 - 5031. [Abstract] [Full Text] [PDF]

				C. Schwarzer, Z. Fu, H. Fischer, and T. E. Machen Redox-independent Activation of NF-{kappa}B by Pseudomonas aeruginosa Pyocyanin in a Cystic Fibrosis Airway Epithelial Cell Line J. Biol. Chem., October 3, 2008; 283(40): 27144 - 27153. [Abstract] [Full Text] [PDF]

				N. Nakao, T. Kurokawa, T. Nonami, G. Tumurkhuu, N. Koide, and T. Yokochi Hydrogen peroxide induces the production of tumor necrosis factor-{alpha} in RAW 264.7 macrophage cells via activation of p38 and stress-activated protein kinase Innate Immunity, June 1, 2008; 14(3): 190 - 196. [Abstract] [PDF]

				S. Aydin, S. Signorelli, T. Lechleitner, M. Joannidis, C. Pleban, P. Perco, W. Pfaller, and P. Jennings Influence of microvascular endothelial cells on transcriptional regulation of proximal tubular epithelial cells Am J Physiol Cell Physiol, February 1, 2008; 294(2): C543 - C554. [Abstract] [Full Text] [PDF]