Uvaol, a
triterpene present in olives and virgin
olive oil, has been shown to possess anti-inflammatory properties and
antioxidant effects. However, until now, no studies have demonstrated its potential effects on allergic
inflammation. The aim of this study was to evaluate the anti-inflammatory effects of
uvaol in a mouse model of
allergy characterized by eosinophil-dominant
inflammation in actively sensitized mice. The anti-inflammatory effect of
uvaol was analyzed in two murine models of allergic
inflammation (
pleurisy and
asthma). In these models, Swiss mice were sensitized and challenged with
ovalbumin (OVA). In the
pleurisy model, the pleural eosinophilic
inflammation and
IL-5 concentrations were examined 24h after the OVA challenge, while in the
asthma model were examined the airway
inflammation via bronchoalveolar lavage (BAL) fluid cytology and lung histopathology analyses. Our results showed that
uvaol decreased the accumulation of eosinophils and the concentration of
IL-5 in pleural effluent.
Uvaol also demonstrated important anti-inflammatory activity by inhibiting production of
IL-5 and influx of leukocytes, mainly of eosinophils, in BAL fluid, but without interfering with levels of
reactive oxygen species in leukocytes. Moreover, the eosinophil infiltration, mucus production, number of alveoli that collapsed, and
IL-5 levels in the lung were clearly decreased by
uvaol treatment. These findings indicate that
uvaol can be a good candidate for the treatment of allergic
inflammation by inhibiting eosinophil influx and
IL-5 production in
ovalbumin-induced
allergy.