Protective effects of fisetin against myocardial ischemia/reperfusion injury.

The underlying mechanism of the myocardial protective effect of fisetin was studied in a rat ischemia/reperfusion injury model. Sprague-Dawley rats were randomly assigned to seven groups and pretreated with different solutions by gavage administration. A rat model of cardiac ischemia/reperfusion injury was established. Plasma levels of Von Willebrand factor (vWF) were determined by ELISA, flow cytometry was used to determine the level of cardiomyocyte apoptosis and 2,3,5-triphenyltetrazolium staining was used to determine the size of myocardial infarcts. Hematoxylin and eosin-stained sections of myocardial tissues were examined for pathological changes. Expressions of nuclear factor (NF)-κB and matrix metallopeptidase 9 (MMP-9) were measured by immunohistochemistry. Compared with the model group, rats pretreated with fisetin, quercetin and aspirin showed significant prolongation of clotting time, prothrombin time, thrombin time and activated partial thromboplastin time. Fisetin treatment better maintained the integrity of myocardial fibers and nuclear integrity, reduced the percentage of apoptotic myocardial cells, inhibited expression of NF-κB, decreased the loss of MMP-9 and reduced nuclear translocation of NF-kB. Rats pretreated with fisetin also demonstrated a significant decrease in plasma levels of vWF. In addition, the protective effect of fisetin on myocardial cells was found to be dose dependent.