Fingolimod protects cultured cortical neurons against excitotoxic death

• Published in: Pharmacological research 2013-01, Vol.67 (1), p.1-9
• Main Authors: Di Menna, Luisa, Molinaro, Gemma, Di Nuzzo, Luigi, Riozzi, Barbara, Zappulla, Cristina, Pozzilli, Carlo, Turrini, Renato, Caraci, Filippo, Copani, Agata, Battaglia, Giuseppe, Nicoletti, Ferdinando, Bruno, Valeria
• Format: Article
• Language: English
• Subjects: Animals; Astrocytes - drug effects; Cell Death - drug effects; Cells, Cultured; Cortical cultures; Excitotoxicity; Female; Fingolimod Hydrochloride; FTY720; Immunosuppressive Agents - pharmacology; Lysophospholipids - pharmacology; Mice; Neuroinflammation; Neurons - drug effects; Neuroprotection; Neuroprotective Agents - pharmacology; Organophosphates - pharmacology; Propylene Glycols - pharmacology; Rats; Sphingosine - analogs & derivatives; Sphingosine - pharmacology
• ISSN: 1043-6618; 1096-1186
• DOI: 10.1016/j.phrs.2012.10.004

Fingolimod (FTY720), a novel drug approved for the treatment of relapsing-remitting multiple sclerosis, activates different sphingosine-1-phosphate receptor (S1PR) subtypes. Its primary mechanism of action is to reduce the egress of T lymphocytes from secondary lymphoid organs, thus restraining neuroinflammation and autoimmunity. However, recent evidence suggests that the action of FTY720 involves S1PRs expressed by cells resident in the CNS, including neurons. Here, we examined the effect of FTY720, its active metabolite, FTY720-P, and sphingosine-1-phosphate (S1P) on neuronal viability using a classical in vitro model of excitotoxic neuronal death. Mixed cultures of mouse cortical cells were challenged with toxic concentrations of N-methyl-d-aspartate (NMDA) for 10min, and neuronal death was assessed 20h later. FTY720, FTY720-P, and S1P were all neuroprotective when applied 18–20h prior to the NMDA pulse. Neuroprotection was attenuated by pertussis toxin, and inhibited by the selective type-1 S1PR (S1P1R) antagonist, W146, and by inhibitors of the mitogen associated protein kinase (MAPK) and the phosphatidylinositol-3-kinase (PtdIns-3-K) pathways. Both FTY720 and FTY720-P retained their protective activity in pure cultures of mouse or rat cortical neurons. These data offer the first direct demonstration that FTY720 and its active metabolite protect neurons against excitotoxic death.