title: Fluoxetine induced suicidal erythrocyte death.
abstract: The antidepressant fluoxetine inhibits ceramide producing acid sphingomyelinase. Ceramide is in turn known to trigger eryptosis the suicidal death of erythrocytes characterized by cell shrinkage and exposure of phosphatidylserine at the erythrocyte surface. Ceramide is effective through sensitizing the erythrocytes to the pro-eryptotic effect of increased cytosolic Ca2+ activity ([Ca2+]i). In nucleated cells, fluoxetine could either inhibit or stimulate suicidal death or apoptosis. The present study tested whether fluoxetine influences eryptosis. To this end cell volume was estimated from forward scatter, phosphatidylserine exposure from annexin V binding, hemolysis from hemoglobin release and [Ca2+]i from Fluo-3 fluorescence intensity. As a result, a 48 h exposure of erythrocytes to fluoxetine (≥25 µM) significantly decreased forward scatter, increased annexin V binding and enhanced [Ca2+]i. The effect on annexin V binding was significantly blunted, but not abolished, in the absence of extracellular Ca2+. In conclusion, fluoxetine stimulates eryptosis, an effect at least in part due to increase of cytosolic Ca2+ activity.
authors.affiliation: Department of Physiology, University of Tuebingen, Gmelinstr. 5, Tuebingen 72076, Germany. kashif_cbc@yahoo.com
authors.forename: Kashif
authors.initials: K
authors.lastname: Jilani
authors.forename: Sigrid
authors.initials: S
authors.lastname: Enkel
authors.forename: Rosi
authors.initials: R
authors.lastname: Bissinger
authors.forename: Ahmad
authors.initials: A
authors.lastname: Almilaji
authors.forename: Majed
authors.initials: M
authors.lastname: Abed
authors.forename: Florian
authors.initials: F
authors.lastname: Lang
mesh_terms: D000814:Aniline Compounds / Q000378:metabolism; D017304:Annexin A5 / Q000378:metabolism; D018687:Antidepressive Agents, Second-Generation / Q000009:adverse effects*; D017209:Apoptosis / Q000187:drug effects*; D002118:Calcium / Q000378:metabolism; D048429:Cell Size / Q000187:drug effects; D002518:Ceramides / Q000378:metabolism; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D004912:Erythrocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005473:Fluoxetine / Q000009:adverse effects*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D010718:Phosphatidylserines / Q000378:metabolism; D011485:Protein Binding; D014966:Xanthenes / Q000378:metabolism
chemical_list: D000814:Aniline Compounds; D017304:Annexin A5; D018687:Antidepressive Agents, Second-Generation; D002518:Ceramides; D010718:Phosphatidylserines; D014966:Xanthenes; D005473:Fluoxetine; C059715:Fluo-3; D002118:Calcium