Phorbol-myristate -acetate (PMA, 1 μM) or butyric acid (2 mM) was used as a positive control for Caco-2/ap1-luc-1 or HT-29/ap1-luc-6 reporter cells respectively. Luciferase activity was measured using the ONE-Glo™. Luciferase Assay System (Promega) according to the manufacturer’s instructions and quantified as relative luminescence units (RLU). All measurements were performed using a microplate reader (Infinite 200, Tecan). Statistical analysis Data are expressed as a mean ± standard error (SEM) calculated over three independent

experiments performed in triplicate. Analysis of statistical significance were performed by ANOVA with Bonferroni post hoc test (adhesion and cytotoxicity assays) or Student’s t-test (IL-8 secretion, NF-κB and AP-1 activation assays) Acknowledgements This work was supported by a BRI grant (Bourse Régionale Industrielle) from the Région Haute-Normandie buy GSK872 and BIOGALENYS. OL is supported by the European Community’s Seventh Framework LY2874455 manufacturer Programme (FP7/2007-2013): MetaHIT, grant agreement HEALTH-F4-2007-201052. We thank Mihai Covasa and Christine Farmer for revising the English manuscript. References 1. Hirakata Y, Izumikawa K, Yamaguchi T, Igimi S, Furuya N, Maesaki S, Tomono K, Yamada Y, Kohno S, Yamaguchi K, et al.:

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