OBJECTIVETo investigate the expression of high mobility group box-1 (HMGB1) in the lung tissue and bronchoalveolar lavage fluid (BALF) of asthmatic mouse models and the influence of dexamethasone (DM).

METHODSEighteen female Balb/C mice were randomly divided PBS control group, OVA group and OVA/DM group, and asthmatic mouse models were established in the latter two groups. The airway responsiveness of the mice was assessed by whole-body plethysmography, and the cells in the BALF were counted and classified, with the supernatants of the BALF collected for detection of the level of HMGB1 by ELISA. The left lung of the mice was collected for HE staining, and the expression of HMGB1 in the right lung tissue was detected by Western blotting.

RESULTSAsthmatic mouse models were successfully established. The level of HMGB1 in the BALF was significantly higher in OVA group than in the control group (6.31 ± 4.05 ng/ml vs 2.59 ± 0.73 ng/ml, P = 0.017), but no significant difference was found between OVA/DM group (3.39 ± 0.50 ng/ml) and OVA group (PP = 0.052). The expression of HMGB1 relative to tubulin was significantly higher in OVA group than in the control group (2.08 ± 0.87 vs 0.85 ± 0.30, P = 0.032), but similar between OVA/DM group (1.15 ± 0.48) and OVA group (PP = 0.133).

CONCLUSIONThe expression of HMGB1 is obviously increased in the lung and BALF of asthmatic mice and DM produces no significant effect on HMGB1 expression, suggesting that HMGB1 may serve as a new therapeutic target for asthma treatment.