Pravastatin protects hyperbaric hyperoxia-induced lung injury via inhibiting inflammation in mice

This study aimed to investigate the protective effects of pravastatin on hyperbaric hyperoxia-induced lung injury (HILI). C57BL/6 mice were randomly assigned into three groups: control group, HILI group and pravastatin (Pra) group. Mice in the HILI and Pra groups were subjected to exposure to pure oxygen at 2.5 atm abs for six hours. Mice in the Pra group were intraperitoneally treated with pravastatin at 15 mg/kg. immediately after exposure. At 24 hours, the lungs were collected for HE staining, TUNEL staining and detection of lung edema, myeloperoxidase (MPO) activity and cytokines, and bronchoalveolar lavage fluid (BALF) was harvested for cell-counting. Pravastatin treatment significantly improved the pathology of the lung after HILI (reduction in thickness of alveolar septum, attenuation of lung edema, fracturing of alveolar septa and decrease in infiltrated leukocytes); reduced the number of apoptotic cells; inhibited lung MPO activity; and regulated the balance between pro-inflammatory and anti-inflammatory cytokines. Our findings suggest that pravastatin may exert a protective effect on lung injury after hyperbaric hyperoxia exposure by inhibiting inflammation.