Óleo de peixe (fonte de ácidos graxos n-3) atenua inflamação das vias aéreas e hiper-reatividade pulmonar induzida por alérgeno em camundongos

Abstract

Fish oil (FO) is rich in n-3 polyunsaturated fatty acids (PUFA), which have been suggested to be anti-inflammatory and are associated with improvement of several inflammatory diseases. In this study, we investigated the influence of FO on allergen-induced lung inflammation and airway hyperreactivity in mice. Male A/J mice were fed either a standard-chow (SC) or a FO diet (FO) for 8 weeks. After 4 weeks, each group was further randomized for ovalbumin (SC-OVA and FO-OVA) or saline (SC-SAL and FO-SAL) challenge. Resistance and elastance were measured at baseline and after aerosolized methacholine, 24h after the last challenge. Bronchoalveolar lavage (BAL) was performed for leukocyte counts and eotaxin-2 quantification. Lung tissue mucus deposition, peribronchiolar matrix deposition and eosinophil infiltration were quantified. Interleukin-13 expression was evaluated by immunohistochemistry and nuclear factor kappa B (NFκB), GATA-3 and peroxisome proliferator-activated receptor gamma (PPARγ) expression was measured by Western blot. OVA challenge resulted in increased eosinophil infiltration, increased inflammatory cytokine production, peribronchiolar matrix and mucus deposition and airway hyperreactivity to aerosolized methacholine. Elevated lung NFκB and GATA-3 expression was noted in OVA-challenged mice, which was attenuated in FO diet-fed mice. Higher PPARγ expression was also detected in the lungs from the FO-fed groups. In conclusion, FO intake attenuated classical asthma features by reducing inflammatory mediator production via GATA-3 and NFκB down-regulation and PPARγ up-regulation. Thus, FO might be an alternative therapy for asthma prevention and control.