title: Mitoxantrone-induced suicidal erythrocyte death.
abstract: OBJECTIVE
  Mitoxantrone, a cytotoxic drug used for the treatment of malignancy and multiple sclerosis, is at least in part effective by triggering apoptosis. Similar to apoptosis of nucleated cells, erythrocytes may enter eryptosis, a type of suicidal cell death. Hallmarks of eryptosis are cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Signalling involved in eryptosis include Ca(2+)-entry, ceramide formation and oxidative stress.
  
  
  METHODS
  Cell volume was estimated from forward scatter, phosphatidylserine-exposure from annexin V binding, formation of reactive oxidant species (ROS) from 2',7'-dichlorodihydrofluorescein-diacetate fluorescence, and ceramide abundance from binding of fluorescent antibodies in flow cytometry.
  
  
  RESULTS
  A 48 hours exposure to mitoxantrone was followed by significant decrease of forward scatter (≥ 5 μg/ml mitoxantrone) and increase of annexin-V-binding (≥ 10 μg/ml mitoxantrone), effects paralleled by significant increases of ROS formation (25 μg/ml mitoxantrone) and ceramide abundance (25 μg/ml mitoxantrone). The effect of mitoxantrone was not significantly modified by nominal absence of extracellular Ca(2+) but significantly blunted by the antioxidant N-acetylcysteine (1 mM).
  
  
  CONCLUSIONS
  Mitoxantrone triggers cell membrane scrambling, an effect not requiring entry of extracellular Ca(2+) but at least partially due to formation of ROS and ceramide.
authors.affiliation: Department of Physiology, University of Tübingen, Tübingen, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Arnold
authors.forename: Rosi
authors.initials: R
authors.lastname: Bissinger
authors.forename: Florian
authors.initials: F
authors.lastname: Lang
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D016923:Cell Death / Q000187:drug effects*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D048429:Cell Size / Q000187:drug effects; D002518:Ceramides / Q000378:metabolism; D004912:Erythrocytes / Q000187:drug effects* / Q000378:metabolism; D005452:Fluoresceins / Q000494:pharmacology; D006801:Humans; D008942:Mitoxantrone / Q000494:pharmacology*; D009103:Multiple Sclerosis / Q000188:drug therapy / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D010718:Phosphatidylserines / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D017304:Annexin A5; D002518:Ceramides; D005452:Fluoresceins; D010718:Phosphatidylserines; D017382:Reactive Oxygen Species; C065013:2',7'-dichlorodihydrofluorescein; D008942:Mitoxantrone; D002118:Calcium; D000111:Acetylcysteine