Unsaponifiable fraction from extra virgin olive oil inhibits the inflammatory response in LPS-activated murine macrophages

•We report the anti-inflammatory activity of unsaponifiable fraction from olive oil.•The fraction inhibits LPS-induced intracellular ROS production in murine macrophages.•NO2- production, INOs and COX-2 overexpression induced by LPS are inhibited.•Down-regulation of NFkB and MAPKs signalling pathways are involved in these effects. Extra virgin olive oil (EVOO) has demonstrated great anti-inflammatory properties. Nowadays, it is clear that its minor components have a key role in these beneficial effects. However, the contribution of the unsaponifiable fraction (UF) to these healthy effects remains unknown. The present study was designed to evaluate UF in LPS stimulated peritoneal macrophages isolated from mice. NO production was analysed by the Griess method and intracellular ROS by fluorescence analysis. In addition, MAPK family activation, IKBα degradation, NFκB-p65, iNOS and COX-2 expression were determined by Western blot. UF exerted anti-inflammatory and anti-oxidant effects inhibiting LPS-induced intracellular ROS and nitrite production. Additionally, UF decreased COX-2 and iNOS protein expression. These effects were related with a down-regulation in NFκB signal signalling pathways and in MAPK phosphorylation. UF of EVOO compounds could play an important role in the anti-inflammatory effect of virgin olive oils and probably provide an attractive complement in management of inflammatory diseases.