Fox nut or gorgon nut (Euryale ferox--Family Nymphaeaceae), popularly known as Makhana, has been widely used in traditional oriental medicine to cure a variety of diseases including kidney problems, chronic diarrhea, excessive leucorrhea and hypofunction of the spleen. Based on the recent studies revealing antioxidant activities of Euryale ferox and its glucosides composition, we sought to determine if Euryale ferox seeds (Makhana) could reduce myocardial ischemic reperfusion injury. Two different models were used: acute model, where isolated rat hearts were preperfused for 15 min with Krebs Henseleit bicarbonate (KHB) buffer containing three different doses of makhana (25, 125 or 250 microg/ml) followed by 30 min of ischemia and 2 h of reperfusion; and chronic model, where rats were given two different doses of makhana (250 and 500 mg/kg/day) for 21 days, after which isolated hearts were subjected to 30 min of ischemia followed by 2 h of reperfusion. In both cases, the hearts of the Makhana treated rats were resistant to ischemic reperfusion injury as evidenced by their improved post-ischemic ventricular function and reduced myocardial infarct size. Antibody array technique was used to identify the cardioprotective proteins. The Makhana-treated hearts had increased amounts of thioredoxin-1 (Trx-1) and thioredoxin-related protein-32 (TRP32) compared to the control hearts. Western blot analysis confirmed increased expression of TRP32 and thioredoxin proteins. In vitro studies revealed that Makhana extracts had potent reactive oxygen species scavenging activities. Taken together, the results of this study demonstrate cardioprotective properties of Makhana and suggest that such cardioprotective properties may be linked with the ability of makhana to induce TRP32 and Trx-1 proteins and to scavenge ROS.