Table of Contents
ISRN Toxicology
Volume 2013, Article ID 792452, 7 pages
http://dx.doi.org/10.1155/2013/792452
Research Article

Activation of the NFκB Pathway Enhances AhR Expression in Intestinal Caco-2 Cells

1IMBE-UMR CNRS 7263, IRD 237 Aix-Marseille Université Campus Timone, Faculté de Pharmacie, 27 boulevard Jean Moulin, 13385 Marseille Cedex 05, France
2UMR INSERM 1062, INRA 1260, Nutrition, Obésité et Risque Thrombotique (NORT), Aix-Marseille Université Campus Timone, Faculté de Pharmacie, 27 boulevard Jean Moulin, 13385 Marseille Cedex 05, France
3Laboratoire de Génie Génétique, Aix-Marseille Université Campus Timone, Faculté de Pharmacie, 27 boulevard Jean Moulin, 13385 Marseille Cedex 05, France

Received 4 July 2013; Accepted 21 August 2013

Academic Editors: P. Pocar and J. C. Rowlands

Copyright © 2013 S. Champion et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Recent data suggest that apart from its well-known role in the regulation of xenobiotic metabolizing enzymes, AhR is also involved in inflammation. However, the influence of inflammation on AhR expression remains unknown. Here, we demonstrated that proinflammatory conditions induced by either PMA or IL-1β enhance AhR expression in Caco-2 cells. This was associated with an increase in AhR promoter activity. By means of directed mutagenesis experiments and the use of proteasome inhibitors, we demonstrated that inflammation-induced AhR expression involved the NFκB pathway but not AP-1. Moreover, conditioned media from PMA-treated Caco-2 cells were also able to induce AhR expression, and this induction was repressed by anti-IL-1β blocking antibodies. Similar results were obtained with conditioned media from PMA-treated THP-1 cells. Taken together, these data suggest that AhR could be involved in vivo in an inflammatory loop. AhR was recently suspected to be implicated in inflammatory bowel disease. Our results support this hypothesis and suggest that AhR could be a new target for inflammatory bowel disease patient management.