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Examining the Role of Sphingosine Kinase‐2 in the Regulation of Endothelial Cell Barrier Integrity
Author(s) -
Dimasi David P.,
Pitson Stuart M.,
Bonder Claudine S.
Publication year - 2016
Publication title -
microcirculation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.793
H-Index - 83
eISSN - 1549-8719
pISSN - 1073-9688
DOI - 10.1111/micc.12271
Subject(s) - microbiology and biotechnology , barrier function , sphingosine , intravital microscopy , in vivo , sphingosine 1 phosphate , chemistry , biology , biochemistry , receptor
Objective A key mediator of vascular EC barrier integrity, S1P, is derived from phosphorylation of sphingosine by the SK ‐1 and SK ‐2. While previous work indicates that SK ‐1 can regulate EC barrier integrity, whether SK ‐2 has a similar role remains to be determined. Methods A cell impedance assay was used to assess human umbilical vein EC and bone marrow EC barrier integrity in vitro , with application of the SK inhibitors ABC 294640, PF 543, SK i, and MP ‐A08. In vivo studies were conducted using intravital microscopy to assess EC barrier integrity in SK ‐1 ( Sphk1 −/− ) and SK ‐2 ( Sphk2 −/− ) knock‐out mice. Results Only ABC 294640 and MP ‐A08, which can both inhibit SK ‐2, caused a decrease in EC barrier integrity in vitro in both cell types. Intravital microscopy revealed that Sphk1 −/− mice had reduced EC barrier integrity compared to WT mice, whereas no change was evident in Sphk2 −/− mice. Conclusions Our data suggest that in vitro inhibition of SK ‐2, can compromise the integrity of the EC monolayer, while SK ‐1 exerts a more dominant control in vivo . These data may have clinical implications and could aid in the development of new treatments for disorders of vascular barrier function.