title: Sphingosine but not sphingosine-1-phosphate stimulates suicidal erythrocyte death.
abstract: Sphingosine kinase 1 phosphorylates sphingosine, which is converted to ceramide by ceramide synthetase. Ceramide triggers eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and phosphatidylserine (PS) exposure at the erythrocyte surface. Erythrocytes lack sphingosine phosphate-degrading enzymes and thus store large quantities of sphingosine phosphate. The present study explored the influence of sphingosine and sphingosine phosphate on eryptosis. [Ca(2+)](i), was estimated from Fluo3 fluorescence, cell volume from forward scatter and PS exposure from annexin V-binding in FACS analysis. Sphingosine (0.1 - 10 μM) but not sphingosine-1- phosphate (0.1 - 10 μM) increased [Ca(2+)](i), decreased cell volume and increased PS-exposure. The observations disclose sphingosine, but not sphingosine-1-phosphate, as a strong inducer of eryptosis.
authors.affiliation: Department of Physiology, University of Tübingen, Tübingen, Germany.
authors.forename: Syed M
authors.initials: SM
authors.lastname: Qadri
authors.forename: Julia
authors.initials: J
authors.lastname: Bauer
authors.forename: Christine
authors.initials: C
authors.lastname: Zelenak
authors.forename: Hasan
authors.initials: H
authors.lastname: Mahmud
authors.forename: Yuliya
authors.initials: Y
authors.lastname: Kucherenko
authors.forename: Seung Hun
authors.initials: SH
authors.lastname: Lee
authors.forename: Klaus
authors.initials: K
authors.lastname: Ferlinz
authors.forename: Florian
authors.initials: F
authors.lastname: Lang
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry; D017209:Apoptosis / Q000187:drug effects*; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000378:metabolism / Q000502:physiology; D004912:Erythrocytes / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D005456:Fluorescent Dyes / Q000737:chemistry; D006801:Humans; D008246:Lysophospholipids / Q000494:pharmacology*; D018408:Patch-Clamp Techniques; D010718:Phosphatidylserines / Q000494:pharmacology; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D014966:Xanthenes / Q000737:chemistry; D000099157:Sphingosine Kinase
chemical_list: D000814:Aniline Compounds; D002118:Calcium; D015220:Calcium Channels; D005456:Fluorescent Dyes; D008246:Lysophospholipids; D010718:Phosphatidylserines; D017853:Phosphotransferases (Alcohol Group Acceptor); D013110:Sphingosine; D014966:Xanthenes; D000099157:Sphingosine Kinase; C059715:Fluo-3; C060506:sphingosine 1-phosphate