标题：High-Genistin Isoflavone Supplementation Modulated Erythrocyte Antioxidant Enzymes and Increased Running Endurance in Rats Undergoing One Session of Exhausting Exercise – A pilot study
摘要：Genistein putatively acts as an antioxidant in vitro . To investigate the in vivo antioxidative activity of genistein, forty-eight male rats were divided into four groups and fed diets with or without 598 mg isoflavone extract per kg of diet for four weeks. On the final day of the study, twenty-four rats were exercised to exhaustion (22 meters/minute at 10% inclination on the treadmill) and then all the rats were sacrificed. The high-genistin isoflavone extract (HGI) diet significantly increased the running time (GE vs. CE: 54 vs. 48 min) and genistein concentrations in the plasma, liver, and gastrocnemius muscle (GE vs. GS: 730.3 vs. 348.5 ng/ml, 529.3 vs. 216.9, and 59.0 vs. 24.9 ng/g, respectively). Exercise doubled genistein concentrations in all tissues and significantly enhanced liver malondialdehyde (MDA). HGI supplementation did not prevent the increase of MDA; instead, it substantially increased MDA levels in muscle tissue (HGI vs. control: 0.46 vs. 0.29 mg/kg). HGI supplementation also maintained the activities of catalase and glutathione peroxidase (GPx) decreased due to exercise (GE vs. GS: 0.113 vs. 0.101 unit/g RBC protein and 0.412 vs. 0.403 µmol/s/mg protein, respectively). It can be concluded that even though HGI modulates erythrocyte antioxidant enzymes against oxidative stress and increases endurance capacity, the supplemented level of HGI does not seem to be optimal for defending the liver and skeletal muscles against oxidative stress .
