Selective inhibition of NF-kappaB and surfactant therapy in experimental meconium-induced lung injury.

Meconium aspiration syndrome (MAS) in newborns is characterized mainly by respiratory failure due to surfactant dysfunction and inflammation. Previous meta-analyses did not prove any effect of exogenous surfactant treatment nor glucocorticoid administration on final outcome of children with MAS despite oxygenation improvement. As we supposed there is the need to intervene in both these fields simultaneously, we evaluated therapeutic effect of combination of exogenous surfactant and selective inhibitor of NF-kappaB (IKK-NBD peptide). Young New Zealand rabbits were instilled by meconium suspension and treated by surfactant alone or surfactant in combination with IKK-NBD, and oxygen-ventilated for 5 h. PaO(2)/FiO(2), oxygenation index, oxygen saturation and ventilation efficiency index were evaluated every hour; post mortem, total and differential leukocyte counts were investigated in bronchoalveolar lavage fluid (BALF) and inflammatory, oxidative and apoptotic markers were assessed in lung tissue homogenates. Exogenous surfactant combined with IKK-NBD improved oxygenation, reduced neutrophil count in BALF and levels of IL-1beta, IL-6, p38 MAPK and caspase 3 in comparison with surfactant-only therapy. It seems that inhibition of inflammation may be strong supporting factor in surfactant treatment of MAS.