title: Fingolimod effects in neuroinflammation: Regulation of astroglial glutamate transporters?
abstract: Fingolimod is an oral sphingosine-1-phosphate-receptor modulator which reduces the recirculation of immune cells and may also directly target glial cells. Here we investigate effects of fingolimod on expression of astroglial glutamate transporters under pro-inflammatory conditions. In astrocyte cell culture, the addition of pro-inflammatory cytokines led to a significant downregulation of glutamate transporters glutamate transporter-1 (slc1a2/SLC1A2) and glutamate aspartate transporter (slc1a3/SLC1A3) expression on the mRNA or protein level. In this setting, the direct application of fingolimod-1 phosphate (F1P) on astrocytes did not change expression levels of slc1a2 and slc1a3 mRNA. The analysis of both transporters on the protein level by Western Blot and immunocytochemistry did also not reveal any effect of F1P. On a functional level, the addition of conditioned supernatants from F1P treated astrocytes to neuronal cell culture did not result in increased neurite growth. In experimental autoimmune encephalomyelitis as a model of multiple sclerosis, fingolimod treatment reduced T cell and macrophages/microglia mediated inflammation and also diminished astrocyte activation. At the same time, fingolimod restored the reduced expression of slc1a2 and slc1a3 in the inflamed spinal cord on the mRNA level and of SLC1A2 and SLC1A3 on the protein level, presumably via indirect, anti-inflammatory mechanisms. These findings provide further evidence for a predominantly peripheral effect of the compound in neuroinflammation.
authors.affiliation: Department of Neurology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany.
authors.forename: De-Hyung
authors.initials: DH
authors.lastname: Lee
authors.affiliation: Department of Neurology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany.
authors.forename: Silvia
authors.initials: S
authors.lastname: Seubert
authors.affiliation: Department of Neurology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Huhn
authors.affiliation: Department of Neurology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany.
authors.forename: Lukas
authors.initials: L
authors.lastname: Brecht
authors.affiliation: Department of Neurology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany.
authors.forename: Caroline
authors.initials: C
authors.lastname: Rötger
authors.affiliation: Department of Neurology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Waschbisch
authors.affiliation: Department of Molecular Neurology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Schlachetzki
authors.affiliation: Institute of Molecular Neurobiology, Ruhr-University, Bochum, Germany.
authors.forename: Alice
authors.initials: A
authors.lastname: Klausmeyer
authors.affiliation: Department of Neurology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany.
authors.forename: Arthur
authors.initials: A
authors.lastname: Melms
authors.affiliation: Institute of Molecular Neurobiology, Ruhr-University, Bochum, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Wiese
authors.affiliation: Department of Molecular Neurology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Winkler
authors.affiliation: Department of Neurology, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany.
authors.forename: Ralf A
authors.initials: RA
authors.lastname: Linker
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000378:metabolism; D002478:Cells, Cultured; D015536:Down-Regulation / Q000187:drug effects*; D027341:Excitatory Amino Acid Transporter 1 / Q000235:genetics / Q000378:metabolism*; D027342:Excitatory Amino Acid Transporter 2 / Q000235:genetics / Q000378:metabolism*; D005260:Female; D000068876:Fingolimod Hydrochloride / Q000494:pharmacology* / Q000627:therapeutic use; D007166:Immunosuppressive Agents / Q000494:pharmacology* / Q000627:therapeutic use; D007249:Inflammation / Q000188:drug therapy / Q000517:prevention & control; D053583:Interleukin-1beta / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016716:PC12 Cells; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D027341:Excitatory Amino Acid Transporter 1; D027342:Excitatory Amino Acid Transporter 2; D007166:Immunosuppressive Agents; D053583:Interleukin-1beta; D012333:RNA, Messenger; C493396:Slc1a2 protein, mouse; C493393:Slc1a3 protein, mouse; D014409:Tumor Necrosis Factor-alpha; D000068876:Fingolimod Hydrochloride