Moreover, immunohistochemical analysis confirmed that BNx-induced decrease in AQP-5 protein expression in lung tissue was also restored by oral administration of AST-120 (Figure 4C,D), suggesting that IS accumulation in lung tissue may play crucial roles in the pathogenesis of ALI through dysregulation of pulmonary AQP-5 expression. Here, AQP5 is linked to acute respiratory distress syndrome.