Lycopene, quercetin and tyrosol prevent macrophage activation induced by gliadin and IFN-γ

Oxidative stress plays an important role in inflammatory process of celiac disease. We have studied the effect of the lycopene, quercetin and tyrosol natural antioxidants on the inducible nitric oxide synthase (NOS) and cyclooxygenase-2 (COX-2) gene expression in RAW 264.7 macrophages stimulated by gliadin in association with IFN-gamma. The IFN-gamma plus gliadin combination treatment was capable of enhancing NOS and COX-2 gene expression and nuclear factor-kappa B (NF-kappa B), interferon regulatory factor-1 (IRF-1) and signal transducer and activator of transcription-1 alpha (STAT-1 alpha) activation induced by reactive oxygen species generation at 24 h. Lycopene, quercetin and tyrosol inhibited all these effects. The results here reported suggest that these compounds may represent non toxic agents for the control of pro-inflammatory genes involved in celiac disease. (c) 2007 Elsevier B.V. All rights reserved.