title: Cardioprotective effects of luteolin during ischemia-reperfusion injury in rats.
abstract: BACKGROUND
  Antioxidants effectively reduce ischemia-reperfusion (IR) injury. The cardioprotective effects of luteolin, a flavonoid that exhibits antioxidant properties and is widely available in many fruits and vegetables, were examined in rats subjected to myocardial IR injury.
  
  
  RESULTS
  Rats were subjected to myocardial ischemia or reperfusion injury to evaluate the antiarrhythmic effects of luteolin. Myocardial infarct size was determined histochemically with triphenyltetrazolium chloride staining of the left ventricle. Luteolin was administered intravenously 15min before occlusion of the coronary artery. The incidence and duration of ventricular tachycardia and ventricular fibrillation and mortality during myocardial ischemia were significantly reduced by luteolin (10µg/kg). Similarly, luteolin (1µg/kg) reduced ventricular arrhythmias and mortality during the reperfusion phase. Pretreatment with luteolin decreased plasma lactate dehydrogenase and nitric oxide (NO) levels. Luteolin (10µg/kg) significantly reduced the myocardial infarct size, as well as malondialdehyde production in tissue samples of myocardial IR injury. Luteolin also downregulated inducible NO synthase protein and mRNA expression, but did not significantly alter neuronal NO synthase or endothelial NO synthase expression.
  
  
  CONCLUSIONS
  Luteolin is capable of protecting the myocardium against IR injury. The actions of luteolin are at least partly mediated through downregulation of NO production and its own antioxidant properties.
authors.affiliation: Department of Pharmacology and Institute of Medicine, Chung Shan Medical University, Chung Shan Medical University Hospital, Taichung, Taiwan.
authors.forename: Pei-Hu
authors.initials: PH
authors.lastname: Liao
authors.forename: Li-Man
authors.initials: LM
authors.lastname: Hung
authors.forename: Yi-Hung
authors.initials: YH
authors.lastname: Chen
authors.forename: Yu-Hsiang
authors.initials: YH
authors.lastname: Kuan
authors.forename: Friedrich Bo-Yuan
authors.initials: FB
authors.lastname: Zhang
authors.forename: Ruey-Hseng
authors.initials: RH
authors.lastname: Lin
authors.forename: Hung-Che
authors.initials: HC
authors.lastname: Shih
authors.forename: Shen-Kou
authors.initials: SK
authors.lastname: Tsai
authors.forename: Shiang-Suo
authors.initials: SS
authors.lastname: Huang
mesh_terms: D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology / Q000627:therapeutic use*; D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use; D002316:Cardiotonic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D004353:Drug Evaluation, Preclinical; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics; D007770:L-Lactate Dehydrogenase / Q000097:blood; D047311:Luteolin / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D009203:Myocardial Infarction / Q000097:blood / Q000150:complications / Q000473:pathology; D015428:Myocardial Reperfusion Injury / Q000097:blood / Q000188:drug therapy*; D009206:Myocardium / Q000201:enzymology; D009569:Nitric Oxide / Q000097:blood; D019001:Nitric Oxide Synthase / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000517:prevention & control; D014693:Ventricular Fibrillation / Q000209:etiology / Q000517:prevention & control
chemical_list: D000889:Anti-Arrhythmia Agents; D000975:Antioxidants; D002316:Cardiotonic Agents; D007527:Isoenzymes; D012333:RNA, Messenger; D009569:Nitric Oxide; D007770:L-Lactate Dehydrogenase; D019001:Nitric Oxide Synthase; D047311:Luteolin