Subcellular distribution of FTY720 and FTY720-phosphate in immune cells - another aspect of Fingolimod action relevant for therapeutic application

Biol Chem. 2015 Jun;396(6-7):795-802. doi: 10.1515/hsz-2014-0287.

Abstract

FTY720 (Fingolimod; Gilenya®) is an immune-modulatory prodrug which, after intracellular phosphorylation by sphingosine kinase 2 (SphK2) and export, mimics effects of the endogenous lipid mediator sphingosine-1-phosphate. Fingolimod has been introduced to treat relapsing-remitting multiple sclerosis. However, little has been published about the immune cell membrane penetration and subcellular distribution of FTY720 and FTY720-P. Thus, we applied a newly established LC-MS/MS method to analyze the subcellular distribution of FTY720 and FTY720-P in subcellular compartments of spleen cells of wild type, SphK1- and SphK2-deficient mice. These studies demonstrated that, when normalized to the original cell volume and calculated on molar basis, FTY720 and FTY720-P dramatically accumulated several hundredfold within immune cells reaching micromolar concentrations. The amount and distribution of FTY720 was differentially affected by SphK1- and SphK2-deficiency. On the background of recently described relevant intracellular FTY720 effects in the nanomolar range and the prolonged application in multiple sclerosis, this data showing a substantial intracellular accumulation of FTY720, has to be considered for benefit/risk ratio estimates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cells, Cultured
  • Female
  • Fingolimod Hydrochloride / metabolism*
  • Fingolimod Hydrochloride / pharmacology*
  • Lysophospholipids / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Multiple Sclerosis / drug therapy
  • Multiple Sclerosis / metabolism
  • Organophosphates / metabolism*
  • Organophosphates / pharmacology*
  • Phosphorylation
  • Phosphotransferases (Alcohol Group Acceptor) / deficiency
  • Phosphotransferases (Alcohol Group Acceptor) / metabolism
  • Sphingosine / analogs & derivatives*
  • Sphingosine / metabolism
  • Sphingosine / pharmacology
  • Spleen / cytology
  • Spleen / metabolism
  • Tandem Mass Spectrometry

Substances

  • FTY 720P
  • Lysophospholipids
  • Organophosphates
  • sphingosine 1-phosphate
  • Phosphotransferases (Alcohol Group Acceptor)
  • sphingosine kinase
  • sphingosine kinase 2, mouse
  • Fingolimod Hydrochloride
  • Sphingosine