Pyruvate enhances recovery of rat hearts after ischemia and reperfusion by preventing free radical generation.
Pyruvate protects myocardium from ischemic and anoxic injury, effects that have been attributed to beneficial metabolic alterations. Pyruvate also reacts with hydrogen peroxide in vitro, and pyruvate prevents free radical injury in other organs. Hearts supplied with 2 mM of pyruvate with glucose during reperfusion recovered significantly more mechanical function (81%) than those provided with 2 mM of acetate (which does not react with free radicals) and glucose (49%) or glucose alone (27%). Pyruvate significantly reduced free radical generation during reperfusion as measured with electron spin resonance using the spin-trap 5,5-dimethyl-1-pyrroline-1-oxide. In a model of direct oxidant stress, hearts were perfused with 0.28 mM of hydrogen peroxide. In this model, loss of function was almost entirely prevented by addition of 2 mM of pyruvate. From these results we conclude an important mechanism of protection when pyruvate is supplied during reperfusion is limitation of oxygen-derived free radical damage.
DeBoer
L W
LW
Department of Medicine, University of Nebraska School of Medicine, Omaha 68198-2265.
Bekx
P A
PA
Han
L
L
Steinke
L
L
D000818:Animals; D003497:Cyclic N-Oxides; D004578:Electron Spin Resonance Spectroscopy; D016166:Free Radical Scavengers; D005609:Free Radicals / Q000378:metabolism; D005947:Glucose; D006321:Heart / Q000187:drug effects / Q000502:physiology / Q000503:physiopathology*; D006339:Heart Rate / Q000187:drug effects; D017202:Myocardial Ischemia / Q000188:drug therapy / Q000503:physiopathology*; D015425:Myocardial Reperfusion; D011773:Pyruvates / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley; D013113:Spin Labels; D013599:Systole / Q000187:drug effects; D013997:Time Factors; D014325:Tromethamine; D016277:Ventricular Function, Left / Q000187:drug effects
D003497:Cyclic N-Oxides; D016166:Free Radical Scavengers; D005609:Free Radicals; C074097:Krebs-Henseleit solution; D011773:Pyruvates; D013113:Spin Labels; D014325:Tromethamine; C017245:5,5-dimethyl-1-pyrroline-1-oxide; D005947:Glucose