The role of NADPH oxidases in diabetic cardiomyopathy.

Systemic changes during diabetes such as high glucose, dyslipidemia, hormonal changes and low grade inflammation, are believed to induce structural and functional changes in the cardiomyocyte associated with the development of diabetic cardiomyopathy. One of the hallmarks of the diabetic heart is increased oxidative stress. NADPH-oxidases (NOXs) are important ROS-producing enzymes in the cardiomyocyte mediating both adaptive and maladaptive changes in the heart.

High- and moderate-intensity training normalizes ventricular function and mechanoenergetics in mice with diet-induced obesity.

Although exercise reduces several cardiovascular risk factors associated with obesity/diabetes, the metabolic effects of exercise on the heart are not well-known. This study was designed to investigate whether high-intensity interval training (HIT) is superior to moderate-intensity training (MIT) in counteracting obesity-induced impairment of left ventricular (LV) mechanoenergetics and function. C57BL/6J mice with diet-induced obesity (DIO mice) displaying a cardiac phenotype with altered substrate utilization and impaired mechanoenergetics were subjected to a sedentary lifestyle or 8-10 weeks of isocaloric HIT or MIT.

High intensity interval training alters substrate utilization and reduces oxygen consumption in the heart.

Aims: although exercise training induces hypertrophy with improved contractile function, the effect of exercise on myocardial substrate metabolism and cardiac efficiency is less clear. High intensity training has been shown to produce more profound effects on cardiovascular function and aerobic capacity than isocaloric low and moderate intensity training. The aim of the present study was to explore metabolic and mechanoenergetic changes in the heart following endurance exercise training of both high and moderate intensity.