title: FTY720 (s)-phosphonate preserves sphingosine 1-phosphate receptor 1 expression and exhibits superior barrier protection to FTY720 in acute lung injury.
abstract: OBJECTIVE
  Effective therapies are needed to reverse the increased vascular permeability that characterizes acute inflammatory diseases such as acute lung injury. FTY720 is a pharmaceutical analog of the potent barrier-enhancing phospholipid, sphingosine 1-phosphate. Because both FTY720 and sphingosine 1-phosphate have properties that may limit their usefulness in patients with acute lung injury, alternative compounds are needed for therapeutic use. The objective of this study is to characterize the effects of FTY720 (S)-phosphonate, a novel analog of FTY720-phosphate, on variables of pulmonary vascular permeability in vitro and alveolar-capillary permeability in vivo.
  
  
  METHODS
  University-affiliated research institute.
  
  
  METHODS
  Cultured human pulmonary endothelial cells; C57BL/6 mice.
  
  
  METHODS
  Endothelial cells were stimulated with sphingosine 1-phosphate receptor 1 agonists to determine effects on sphingosine 1-phosphate receptor 1 expression. Acute lung injury was induced in C57BL/6 mice with bleomycin to assess effects of sphingosine 1-phosphate receptor 1 agonists.
  
  
  RESULTS
  FTY720 (S)-phosphonate potently increases human pulmonary endothelial cell barrier function in vitro as measured by transendothelial electrical resistance. Reduction of sphingosine 1-phosphate receptor 1 with small interference RNA significantly attenuates this transendothelial electrical resistance elevation. FTY720 (S)-phosphonate maintains endothelial sphingosine 1-phosphate receptor 1 protein expression in contrast to greater than 50% reduction after incubation with sphingosine 1-phosphate, FTY720, or other sphingosine 1-phosphate receptor 1 agonists. FTY720 (S)-phosphonate does not induce β-arrestin recruitment, sphingosine 1-phosphate receptor 1 ubiquitination, and proteosomal degradation that occur after other agonists. Intraperitoneal administration of FTY720 (S)-phosphonate every other day for 1 week in normal or bleomycin-injured mice maintains significantly higher lung sphingosine 1-phosphate receptor 1 expression compared with FTY720. FTY720 fails to protect against bleomycin-induced acute lung injury in mice, while FTY720 (S)-phosphonate significantly decreases lung leak and inflammation.
  
  
  CONCLUSIONS
  FTY720 (S)-phosphonate is a promising barrier-promoting agent that effectively maintains sphingosine 1-phosphate receptor 1 levels and improves outcomes in the bleomycin model of acute lung injury.
authors: 1Institute for Personalized Respiratory Medicine, Department of Medicine, University of Illinois, Chicago, IL. 2Department of Chemistry and Biochemistry, Queens College of The City University of New York, Flushing, NY.
authors: Lichun
authors: L
authors: Wang
authors: Saad
authors: S
authors: Sammani
authors: Liliana
authors: L
authors: Moreno-Vinasco
authors: Eleftheria
authors: E
authors: Letsiou
authors: Ting
authors: T
authors: Wang
authors: Sara M
authors: SM
authors: Camp
authors: Robert
authors: R
authors: Bittman
authors: Joe G N
authors: JG
authors: Garcia
authors: Steven M
authors: SM
authors: Dudek
mesh_terms: D055371:Acute Lung Injury / Q000188:drug therapy* / Q000503:physiopathology; D000818:Animals; D019390:Arrestins / Q000187:drug effects / Q000378:metabolism*; D001761:Bleomycin / Q000494:pharmacology; D015153:Blotting, Western; D002199:Capillary Permeability / Q000187:drug effects*; D002478:Cells, Cultured; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D000068876:Fingolimod Hydrochloride; D005455:Fluorescent Antibody Technique; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D011409:Propylene Glycols / Q000494:pharmacology*; D011897:Random Allocation; D043562:Receptors, G-Protein-Coupled / Q000187:drug effects / Q000378:metabolism; D049349:Receptors, Lysosphingolipid / Q000187:drug effects / Q000378:metabolism*; D012680:Sensitivity and Specificity; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000071557:beta-Arrestins
chemical_list: D019390:Arrestins; D011409:Propylene Glycols; D043562:Receptors, G-Protein-Coupled; D049349:Receptors, Lysosphingolipid; D000071557:beta-Arrestins; D001761:Bleomycin; D000068876:Fingolimod Hydrochloride; D013110:Sphingosine