Effects of dexamethasone on neutrophil airway inflammation and HMGB1 expression in asthmatic mice / 解放军医学杂志

ABSTRACT

Objective: To investigate the effect of dexamethasone intervention on neutrophil airway inflammation and high mobility group box 1 protein (HMGB1) expression in asthmatic mice. Methods: Forty healthy SPF grade female Balb/c mice were randomly divided into four groups (n=10) Control group, Asthma group, 1 mg/kg dexamethasone intervention group and 5 mg/kg dexamethasone intervention group. The asthmatic mice model was induced by egg-free ovalbumin. The airway hyper-responsiveness was measured by the invasive pulmonary function instrument; the number and classification of inflammatory cells in bronchoalveolar lavage fluid (BALF) were detected; lung pathological changes were observed by HE staining; HMGB1 expression was detected by immunohistochemistry and Western blotting. Results: Compared with Control group, the airway responsiveness of asthmatic mice was significantly enhanced (P0.05). Conclusions: The expression of HMGB1 in airway epithelium and lung tissue of asthmatic mice with neutrophilic airway inflammation was significantly increased. After dexamethasone intervention, asthmatic mice still showed higher neutrophilic airway inflammation and expression of HMGB1 in lung tissue, suggesting that HMGB1 may be associated with neutrophilic airway inflammation and glucocorticoid resistance in asthma.