ALI and its exacerbated form, acute respiratory distress syndrome (ARDS), are categorized by their symptoms and severity according to the Berlin Definition. ALI is characterized by increased permeability of the alveolar-capillary barrier
, which consequently leads to lung edema with pulmonary infiltrates and hypoxemia., ALI patients manifest significant pulmonary inflammation that causes flooding of the pulmonary alveoli, resulting in obstructed gas exchange and consequent hypoxemia.
Studies had proved that TNF-a derived TIP peptide inhalation could reduce the extravascular lung water index as well as increase the PaO(2)/FiO(2) ratio., The protective role of TNF-derived TIP peptide lies in that through binding to epithelial sodium channel-a, it is able to strengthen the barrier function and maintain permeability of the alveolar-capillary barrier
Moreover, the alveolar epithelium damage will lead to an increase in the permeability of the alveolar-capillary barrier
, which in combination with changes in hydrostatic and oncotic pressures, might lead to the formation of pulmonary edema.,