Efficacy of Edaravone, a Free Radical Scavenger, on Left Ventricular Function and Structure in Diabetes Mellitus

This study was designed to assess the efficacy of edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one), a free radical scavenger that possesses anti-oxidant effects, on cardiac function and fine structure of the left ventricular myocardium in diabetes mellitus. Male Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model of spontaneous development of type II diabetes (30 weeks; n = 15) were divided into two groups and treated with edaravone 30 mg/kg/d or vehicle for 2 weeks. OLETF rats showed hyperglycemia (352 ± 71 mg/dl vs normal control; 128 ± 52 mg/dl), increased thiobarbituric acid-reactive substances (TBARS; 6.9 ± 2.5 n M/ml vs 2.8 ± 0.6 n M/ml), and decreased superoxide dismutase activity (21.5 ± 0.9 U/ml vs 25.8 ± 0.7 U/ml). Increased left ventricular end-diastolic pressure (12 ± 3 mm Hg vs 6 ± 2 mm Hg) and hypertrophied cardiocytes (23.1 ± 1.4 vs 17.6 ± 1.0 μm) were also observed (P < 0.05, respectively). Edaravone could not improve plasma glucose level and hemodynamic parameters but significantly decreased TBARS values (3.8 ± 0.5) and increased superoxide dismutase activity (24.5 ± 0.8) (vs OLETF, P < 0.05, respectively). Moreover, edaravone effectively preserved cardiocyte diameter (18.2 ± 0.9 μm) and the fine structure of mitochondria. Thus, edaravone exhibits modest cardiac protection in diabetes mellitus independent of blood sugar level.