title: The challenge to verify ceramide's role of apoptosis induction in human cardiomyocytes--a pilot study.
abstract: BACKGROUND
  Cardioplegia and reperfusion of the myocardium may be associated with cardiomyocyte apoptosis and subsequent myocardial injury. In order to establish a pharmacological strategy for the prevention of these events, this study aimed to verify the reliability of our human cardiac model and to evaluate the pro-apoptotic properties of the sphingolipid second messenger ceramide and the anti-apoptotic properties of the acid sphingomyelinase inhibitor amitryptiline during simulated cardioplegia and reperfusion ex vivo.
  
  
  METHODS
  Cardiac biopsies were retrieved from the right auricle of patients undergoing elective CABG before induction of cardiopulmonary bypass. Biopsies were exposed to ex vivo conditions of varying periods of cp/rep (30/10, 60/20, 120/40 min). Groups: I (untreated control, n = 10), II (treated control cp/rep, n = 10), III (cp/rep + ceramide, n = 10), IV (cp/rep + amitryptiline, n = 10) and V (cp/rep + ceramide + amitryptiline, n = 10). For detection of apoptosis anti-activated-caspase-3 and PARP-1 cleavage immunostaining were employed.
  
  
  RESULTS
  In group I the percentage of apoptotic cardiomyocytes was significantly (p < 0.05) low if compared to group II revealing a time-dependent increase. In group III ceramid increased and in group IV amitryptiline inhibited apoptosis significantly (p < 0.05). In contrast in group V, under the influence of ceramide and amitryptiline the induction of apoptosis was partially suppressed.
  
  
  CONCLUSIONS
  Ceramid induces and amitryptiline suppresses apoptosis significantly in our ex vivo setting. This finding warrants further studies aiming to evaluate potential beneficial effects of selective inhibition of apoptosis inducing mediators on the suppression of ischemia/reperfusion injury in clinical settings.
authors: Children's University Hospital, Div, Congenital & Pediatric Cardiac Surgery; University Hospital Tübingen, Germany. engin.usta@gmx.de
authors: Engin
authors: E
authors: Usta
authors: Migdat
authors: M
authors: Mustafi
authors: Ferruh
authors: F
authors: Artunc
authors: Tobias
authors: T
authors: Walker
authors: Vladimir
authors: V
authors: Voth
authors: Hermann
authors: H
authors: Aebert
authors: Gerhard
authors: G
authors: Ziemer
mesh_terms: D000368:Aged; D017209:Apoptosis / Q000187:drug effects*; D001706:Biopsy; D002478:Cells, Cultured; D002518:Ceramides / Q000494:pharmacology*; D001026:Coronary Artery Bypass; D005500:Follow-Up Studies; D006324:Heart Arrest, Induced / Q000379:methods; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D010865:Pilot Projects; D011300:Preoperative Care / Q000379:methods*
chemical_list: D002518:Ceramides