The Protective Effect of Egr-1 Antisense Oligodeoxyribonucleotide on Myocardial Injury Induced by Ischemia-reperfusion and Hypoxia-reoxygenation
Aims: Our previous studies have shown that myocardial ischemia-reperfusion (I/R) injury is related closely with early growth response (Egr)-1 overexpression. The present study is to confirm thoroughly the effects of Egr-1 on the occurrance and development of myocardial I/R injury. Methods: The Sprague-Dawley rat myocardial I/R model and cultured cardiomyocyte hypoxia-reoxygenation (H/R) model were established. The synthesized Egr-1 antisense oligodeoxyribonucleotide (AS-ODN) was transfected into myocardial tissues and cells. Hemodynamic parameters, myeloperoxidase (MPO), cardiac troponin I (cTnI), tumor necrosis factor-α (TNF-α), morphology, spontaneous beat and cell viability were measured to assess the degree of injury and inflammation of myocardial tissues and cells. Results: In vivo, Egr-1 AS-ODN significantly attenuated injury and inflammation of myocardial tissues caused by I/R evidenced by the amelioration of hemodynamics and the reduction in MPO activity. In vitro, Egr-1 AS-ODN significantly relieved injury and inflammation of cultured cardiomyocyte caused by H/R evidenced by the improvement in morphology, structure and beat as well as the decrease in leakage of cTnI and release of TNF-α from cultured cardiomyocyte. Conclusions: These data suggest that Egr-1 plays a vital role in the pathogenesis of myocardial I/R injury and Egr-1 AS-ODN could protect the myocardium from I/R injury.