title: Oral pretreatment with a green tea polyphenol for cardioprotection against ischemia-reperfusion injury in an isolated rat heart model.
abstract: OBJECTIVE
  Ischemia-reperfusion injury is among the most serious problems in cardiac surgery. Epigallocatechin-3-gallate, a major polyphenolic component of green tea, is thought to be cardioprotective through its antioxidant activities. We investigated cardioprotective effects of oral epigallocatechin-3-gallate pretreatment against ischemia-reperfusion injury in isolated rat hearts and considered possible underlying mechanisms.
  
  
  METHODS
  Rats were given epigallocatechin-3-gallate solution orally at 0.1, 1, or 10 mmol/L (n=12 per group) for 2 weeks; controls (n=12) received tap water alone for 2 weeks. Subsequently, Langendorff-perfused hearts were subjected to global ischemia for 30 minutes, followed by 60 minutes of reperfusion.
  
  
  RESULTS
  Recoveries at 60 minutes after reperfusion of left ventricular developed pressure and maximum positive and minimum negative first derivatives of left ventricular pressure were significantly higher in 1-mmol/L group than in 0.1-mmol/L (P<.0001), 10-mmol/L (P<.05), and control (P<.0001) groups. Oxidative stress after reperfusion, as reflected by 8-hydroxy-2'-deoxyguanosine index, was lower in 1-mmol/L group than in control (P<.01) and 0.1-mmol/L (P<.05) groups. Western blot analysis after reperfusion showed p38 activation and active caspase-3 expression to be lower in 1-mmol/L group than in control group (P<.05).
  
  
  CONCLUSIONS
  Oral pretreatment with epigallocatechin-3-gallate preserved cardiac function after ischemia-reperfusion, an effect that may involve its antioxidative, antiapoptotic properties, although a high dose did not lead to dramatic improvement in cardiac function. Oral epigallocatechin-3-gallate pretreatment may be a novel and simple cardioprotective method for preventing perioperative cardiac dysfunction in cardiac surgery.
authors.affiliation: Department of Cardiovascular Surgery, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Yanagi
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Matsumura
authors.forename: Akira
authors.initials: A
authors.lastname: Marui
authors.forename: Manabu
authors.initials: M
authors.lastname: Morishima
authors.forename: Suong-Hyu
authors.initials: SH
authors.lastname: Hyon
authors.forename: Tadashi
authors.initials: T
authors.lastname: Ikeda
authors.forename: Ryuzo
authors.initials: R
authors.lastname: Sakata
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000284:Administration, Oral; D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage* / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D028241:Camellia sinensis; D002316:Cardiotonic Agents / Q000008:administration & dosage* / Q000097:blood; D053148:Caspase 3 / Q000378:metabolism; D002392:Catechin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D009206:Myocardium / Q000378:metabolism* / Q000473:pathology; D018384:Oxidative Stress / Q000187:drug effects*; D010477:Perfusion; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D016277:Ventricular Function, Left / Q000187:drug effects*; D017725:Ventricular Pressure / Q000187:drug effects; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D000975:Antioxidants; D002316:Cardiotonic Agents; D000080242:8-Hydroxy-2'-Deoxyguanosine; D002392:Catechin; C045651:epigallocatechin gallate; D048051:p38 Mitogen-Activated Protein Kinases; C505410:Casp3 protein, rat; D053148:Caspase 3; D003849:Deoxyguanosine