Metabolic remodeling of glucose, fatty acid and redox pathways in the heart of type 2 diabetic mice

Hearts from type 2 diabetic animals display perturbations in excitation-contraction coupling, impairing myocyte contractility and delaying relaxation, along with altered substrate consumption patterns. Under high glucose and β-adrenergic stimulation conditions, palmitate can, at least in part, offset left ventricle (LV) dysfunction in hearts from diabetic mice improving contractility and relaxation while restoring coronary perfusion pressure. Fluxome calculations of central catabolism in diabetic hearts show that, in presence of palmitate, there is a metabolic remodeling involving tricarboxylic acid cycle, polyol and pentose phosphate pathways, leading to improved redox balance in cytoplasmic and mitochondrial compartments. Under high glucose and increased energy demand, the metabolic/fluxomic re-direction leading to restored redox balance imparted by palmitate helps explain maintained LV function and may contribute to design novel therapeutic approaches to prevent cardiac dysfunction in diabetic patients.