A sphingosine 1-phosphate 1 receptor agonist modulates brain death-induced neurogenic pulmonary injury

Am J Respir Cell Mol Biol. 2011 Nov;45(5):1022-7. doi: 10.1165/rcmb.2010-0267OC. Epub 2011 May 26.

Abstract

Lung transplantation remains the only viable therapy for patients with end-stage lung disease. However, the full utilization of this strategy is severely compromised by a lack of donor lung availability. The vast majority of donor lungs available for transplantation are from individuals after brain death (BD). Unfortunately, the early autonomic storm that accompanies BD often results in neurogenic pulmonary edema (NPE), producing varying degrees of lung injury or leading to primary graft dysfunction after transplantation. We demonstrated that sphingosine 1-phosphate (S1P)/analogues, which are major barrier-enhancing agents, reduce vascular permeability via the S1P1 receptor, S1PR1. Because primary lung graft dysfunction is induced by lung vascular endothelial cell barrier dysfunction, we hypothesized that the S1PR1 agonist, SEW-2871, may attenuate NPE when administered to the donor shortly after BD. Significant lung injury was observed after BD, with increases of approximately 60% in bronchoalveolar lavage (BAL) total protein, cell counts, and lung tissue wet/dry (W/D) weight ratios. In contrast, rats receiving SEW-2871 (0.1 mg/kg) 15 minutes after BD and assessed after 4 hours exhibited significant lung protection (∼ 50% reduction, P = 0.01), as reflected by reduced BAL protein/albumin, cytokines, cellularity, and lung tissue wet/dry weight ratio. Microarray analysis at 4 hours revealed a global impact of both BD and SEW on lung gene expression, with a differential gene expression of enriched immune-response/inflammation pathways across all groups. Overall, SEW served to attenuate the BD-mediated up-regulation of gene expression. Two potential biomarkers, TNF and chemokine CC motif receptor-like 2, exhibited gene array dysregulation. We conclude that SEW-2871 significantly attenuates BD-induced lung injury, and may serve as a potential candidate to improve human donor availability.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Brain Death / metabolism*
  • Bronchoalveolar Lavage Fluid / chemistry
  • Capillary Permeability / drug effects
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism
  • Gene Expression / drug effects
  • Lung / drug effects
  • Lung / metabolism
  • Lung Injury / drug therapy*
  • Lung Injury / etiology
  • Lung Injury / pathology
  • Male
  • Oxadiazoles / pharmacology*
  • Pulmonary Edema / complications
  • Pulmonary Edema / drug therapy*
  • Pulmonary Edema / etiology
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, CCR2 / genetics
  • Receptors, CCR2 / metabolism
  • Receptors, Lysosphingolipid / agonists*
  • Thiophenes / pharmacology*
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / metabolism
  • Up-Regulation / drug effects

Substances

  • Ccr2 protein, rat
  • Oxadiazoles
  • Receptors, CCR2
  • Receptors, Lysosphingolipid
  • SEW2871
  • Thiophenes
  • Tumor Necrosis Factor-alpha