title: Stimulation of eryptosis by cryptotanshinone.
abstract: OBJECTIVE
  Cryptotanshinone, a component of Salvia miltiorrhiza Bunge roots, may trigger suicidal death or apoptosis of tumor cells and has thus been recommended for the prevention and treatment of malignancy. On the other hand, Cryptotanshinone has been shown to counteract apoptosis of neurons and hepatocytes. Similar to apoptosis of nucleated cells, erythrocytes may enter eryptosis, a suicidal death characterized by cell shrinkage and phosphatidylserine translocation to the erythrocyte surface. Eryptosis may be triggered by increase of cytosolic Ca(2+)-activity ([Ca(2+)]i). The present study explored whether Cryptotanshinone stimulates eryptosis.
  
  
  METHODS
  Forward scatter was taken as measure of cell volume, annexin V binding for identification of phosphatidylserine-exposing erythrocytes and Fluo3-fluorescence for determination of [Ca(2+)]i.
  
  
  RESULTS
  A 48 h exposure of human erythrocytes to Cryptotanshinone (10 µM) was followed by significant decrease of forward scatter, significant increase of the percentage annexin-V-binding cells and significant increase of [Ca(2+)]i. The effect of Cryptotanshinone (1 µM) on annexin-V-binding was virtually abrogated by removal of extracellular Ca(2+).
  
  
  CONCLUSIONS
  Cryptotanshinone is a powerful stimulator of suicidal erythrocyte death or eryptosis, which is effective mainly, if not exclusively, by stimulation of Ca(2+) entry.
authors.affiliation: Department of Physiology, University of Tübingen, Tübingen, Germany.
authors.forename: Rosi
authors.initials: R
authors.lastname: Bissinger
authors.forename: Adrian
authors.initials: A
authors.lastname: Lupescu
authors.forename: Christine
authors.initials: C
authors.lastname: Zelenak
authors.forename: Kashif
authors.initials: K
authors.lastname: Jilani
authors.forename: Florian
authors.initials: F
authors.lastname: Lang
mesh_terms: D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D004912:Erythrocytes / Q000187:drug effects* / Q000378:metabolism; D005434:Flow Cytometry; D006801:Humans; D010616:Phenanthrenes / Q000494:pharmacology*
chemical_list: D017304:Annexin A5; D010616:Phenanthrenes; C037886:cryptotanshinone