Protective effect of surfactant inhalation against warm ischemic injury in an isolated rat lung ventilation model

PLoS One. 2013 Aug 29;8(8):e72574. doi: 10.1371/journal.pone.0072574. eCollection 2013.

Abstract

Warm ischemia-reperfusion injury remains a crucial issue in transplantation following the cardiac death of donors. Previously, we showed that surfactant inhalation during warm ischemia mitigated ischemia-reperfusion injury. This study investigated the mechanisms of surfactant inhalation protection of the warm ischemic lung after reoxygenation with ventilation alone. In an isolated rat lung ventilation model, cardiac arrest was induced in the CTRL (control) and SURF (surfactant treatment) groups by ventricular fibrillation. Ventilation was restarted 110 min later; the lungs were flushed, and a heart and lung block was procured. In the SURF group, a natural bovine surfactant (Surfacten®) was inhaled for 3 min at the end of warm ischemia. In the Sham (no ischemia) group, lungs were flushed, procured, and ventilated in the same way. Afterwards, the lungs were ventilated with room air without reperfusion for 60 min. Surfactant inhalation significantly improved dynamic compliance and airway resistance. Moreover, surfactant inhalation significantly decreased inducible nitric oxide synthase and caspase-3 transcript levels, and increased those of Bcl-2 and surfactant protein-C. Immunohistochemically, lungs in the SURF group showed weaker staining for 8-hydroxy-2'-deoxyguanosine, inducible nitric oxide synthase, and apoptosis, and stronger staining for Bcl-2 and surfactant protein-C. Our results indicate that surfactant inhalation in the last phase of warm ischemia mitigated the injury resulting from reoxygenation after warm ischemia. The reduction in oxidative damage and the inhibition of apoptosis might contribute to the protection of the warm ischemic lungs.

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Administration, Inhalation
  • Animals
  • Caspases / metabolism
  • In Vitro Techniques
  • Lung / drug effects
  • Lung / metabolism
  • Lung / pathology
  • Lung / physiopathology
  • Lung Transplantation / adverse effects*
  • Male
  • Nitric Oxide Synthase Type II / metabolism
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Pulmonary Surfactant-Associated Protein C / metabolism
  • Pulmonary Surfactants / administration & dosage*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rats
  • Reperfusion Injury / genetics
  • Reperfusion Injury / metabolism
  • Reperfusion Injury / physiopathology
  • Reperfusion Injury / prevention & control*
  • Respiration, Artificial
  • Respiratory Function Tests
  • Warm Ischemia / adverse effects*

Substances

  • Proto-Oncogene Proteins c-bcl-2
  • Pulmonary Surfactant-Associated Protein C
  • Pulmonary Surfactants
  • RNA, Messenger
  • Adenosine Triphosphate
  • Nitric Oxide Synthase Type II
  • Caspases

Grants and funding

No current external funding sources for this study.