The effect of safranal, a constituent of Crocus sativus (saffron), on tracheal responsiveness, serum levels of cytokines, total NO and nitrite in sensitized guinea pigs

BackgroundThe effect of safranal (one of the constituents of Crocus sativus) on ovalbumin (OVA) sensitized guinea pigs was examined.MethodsOne group of sensitized guinea pigs were given drinking water alone (group S), three groups drinking water containing three concentrations of safranal and one group contain dexamethasone (S + D). Tracheal responses (TR) of the animals to methacholine as effective concentration causing 50% of maximum response (EC50 M), TR to 0.1% OVA, relative to contraction induced by 100 μM methacholine, IL-4, IFN-γ, total NO and nitrite levels in serum were measured.ResultsThe TR to both methacholine and OVA, the level of total NO, nitrite and IL-4 significantly increased but IFN-γ and IFN-γ/IL-4 ratio was decreased in group S compared controls (p < 0.05 to p < 0.001). The TR to both methacholine and OVA in treated animals with dexamethasone and all concentrations of safranal were significantly decreased compared to S group (p < 0.01 to p < 0.001). The level of serum IL-4 in treated guinea pigs was significantly decreased but IFN-γ and IFN-γ/IL-4 ratio was increased compared to S group (p < 0.01 to p < 0.001). The levels of total NO and nitrite were significantly decreased in treated groups compared to sensitized group (p < 0.05 to p < 0.001).ConclusionThese results showed a preventive effect for safranal on tracheal responses and serum cytokine, total NO and nitrite levels as well as increased Th1/Th2 balance in sensitized guinea pigs.