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

Background: The effect of safranal (one of the constituents of Crocus sativus) on ovalbumin (OVA) sensitized guinea pigs was examined. Methods: One 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 mu M methacholine, IL-4, IFN-gamma, total NO and nitrite levels in serum were measured. Results: The TR to both methacholine and OVA, the level of total NO, nitrite and IL-4 significantly increased but IFN-gamma and IFN-gamma/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 top < 0.001). The level of serum IL-4 in treated guinea pigs was significantly decreased but IFN-gamma and IFN-gamma/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). Conclusion: These 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. (C) 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.