Respiratory failure was achieved by triple-hit lung injury (repeated broncho-alveolar lavage, injurious ventilation, tracheal lipopolysaccharide instillation, each intervention 24 h apart) in twenty-four domestic piglets aged 2–6 days and subject to mechanical ventilation. Following each lung injury protocol the piglets were treated with surfactant alone or with surfactant + DOPG.
Within 72 h of mechanical ventilation, we observed significantly improved gas exchange (oxygenation and ventilation), lung mechanics (compliance and resistance of the respiratory system), and pulmonary oedema (extra-vascular lung water index) in the surfactant + DOPG group. This favourable clinical effect could be attributed to improved surfactant function, reduced sPLA2 secretion, inhibition of macrophage migration, reduced alveolar epithelial apoptosis, and suppression of amphiregulin and TGF-尾1 expression in pulmonary tissues as a prerequisite for fibrous lung repair.
We conclude that surfactant fortified by DOPG preserves lung function, and prevents alveolar epithelial injury and fibrous stimulus by reduction of sPLA2 in a neonatal model of acute respiratory distress syndrome without any relevant discernable side effects. Hence, DOPG supplementation in a neonatal lung exerts important function protecting effects and seems to be justified in cases of overwhelming pulmonary inflammation.