The effect of Nigella sativa alone, and in combination with dexamethasone, on tracheal muscle responsiveness and lung inflammation in sulfur mustard exposed guinea pigs.

ETHNOMEDICAL RELEVANCE: The anti-inflammatory activity of both systemic and local administrations of essential oil from Nigella sativa L. has been shown. Therefore, the effect of Nigella sativa on tracheal responsiveness (TR) and lung inflammation of sulfur mustard (SM) exposed guinea pigs was examined. Guinea pigs were exposed to diluent solution (control group), inhaled SM (SME group), SME treated with Nigella sativa (SME+N), SME treated with dexamethasone (SME+D) and SME treated with both drugs (SME+N+D), (n=7 for each group). TR to methacholine, total white blood cell (WBC) and differential WBC count of lung lavage, and serum cytokines were measured 14 days post-exposure. The values of TR, eosinophil, monocyte, lymphocyte, interleukine-4 (IL-4) and interferon gamma (IFN-γ) of SME group were significantly higher than those of controls (p<0.05 to p<0.001). The TR in SME+N, SME+D and SME+N+D was significantly lower compared to that of SME group (p<0.01 for all cases). The percentage of eosinophil in SME+D, and the percentage of monocyte in SME+N+D (p<0.05 to p<0.01) were significantly lower than those in SME group. The neutrophil number was decreased in SME+N and SME+N+D groups compared to SME animals (p<0.05 to p<0.01). IL-4 levels in serum of SME+N (p<0.01), SME+D (p<0.05), SME+N+D (p<0.01) and IFN-γ in SME+N (p<0.05) were greater than those in SME animals. These results showed a preventive effect of Nigella sativa on TR and lung inflammation of SM exposed guinea pigs. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.