Eftekhari, ParivashHajizadeh, SohrabReza Raoufy, MohammadReza Masjedi, MohammadYang, MingHansbro, NicoleLi, Jing JingFoster, Paul S2015-12-101611-2156http://hdl.handle.net/1885/63747Oxidative stress appears to have an important role in glucocorticoid insensitivity, as a crucial problem in asthma therapy. We studied the preventive effect of antioxidant N-acetylcysteine (NAC) on the airway hyper-responsiveness (AHR) and the accumulation of inflammatory cells in the airways in an animal model of steroid resistant acute exacerbation of asthma. Systemically sensitized Balb/C mice were exposed to Ovalbumin aerosol on days 13, 14, 15 and 16, followed by intratracheal lipopolysaccharide (LPS) to induce acute exacerbation. NAC (intraperitoneal, 320 mg/kg 30 min before and 12 hours after each challenge) reduced hyperresponsiveness with/out dexamethasone. LPS application caused neutrophilia in bronchoalveolar lavage fluid (BALF) and eosinophil count was higher than respective control in BALF as well as neutrophils after dexamethasone treatment. NAC significantly decreased neutrophil and eosinophil count in BALF as well as inflammatory cytokines (IL-13 and IL-5).We concluded that addition of NAC to asthma therapy has beneficial preventive effects in an animal model of steroid resistant acute exacerbation of asthma.Keywords: acetylcysteine; glucocorticoid; interleukin 13; interleukin 5; steroid; animal experiment; animal model; article; asthma; controlled study; disease exacerbation; disease severity; drug effect; eosinophil count; hormone sensitivity; lung lavage; male; mous Acute exacerbation; Eosinophil; N-acetylcysteine; Neutrophil; Steroid resistant asthma20132016-02-24