Protective Effect of Erdosteine Against Hypochlorous Acid-induced Acute Lung Injury and Lipopolysaccharide-induced Neutrophilic Lung Inflammation in Mice

The effect of erdosteine, a mucoactive drug, on hypochlorous acid (HOCl)-induced lung injury, and the lipopolysaccharide (LPS)-induced increase in tumour necrosis factor-α (TNF-α) production and neutrophil recruitment into the airway, was investigated. Male BALB/c mice were orally administered erdosteine (3–100 mg kg−1), ambroxol hydrochloride (ambroxol) (3–30 mg kg−1), S-carboxymethyl-L-cysteine (S-CMC) (100–600 mg kg−1) or prednisolone (10 mg kg−1), 1h before intratracheal injection of HOC1 or LPS. In the HOCl-injected mice, erdosteine markedly suppressed increases in the ratios of lung wet weight to bodyweight and lung dry weight to bodyweight, whereas the other mucoactive drugs ambroxol and S-CMC had little effect. Erdosteine also inhibited the LPS-induced neutrophil influx, although it did not affect the increased level of TNF-α in the bronchoalveolar lavage fluid. The results suggest that attenuation of reactive oxygen species and neutrophil recruitment is involved in the clinical efficacy of erdosteine in the treatment of chronic bronchitis.