This chapter aims to provide an implicit introduction to the role of miRNAs in regulating cardiac
metabolism. The homeostasis of glucose, lipid, protein, and energy, which is critical for normal cardiovascular
function, is maintained by cellular metabolism. Metabolic perturbation occurs in various types of cardiac disease,
including myocardial ischemia, cardiac hypertrophy, heart failure, diabetic cardiomyopathy, atherosclerosis, etc.
The depletion of high-energy-phosphate metabolites may contribute to heart failure, and a decreased PCr/ATP
ratio has been found in cardiac muscle of heart failure patients and animal models of heart failure. A major
determinant of glycolytic flux is glucose transport; glucose enters cardiac cells via the facilitative glucose
transporters GLUT1 and GLUT4. Several miRNAs have been demonstrated to produce regulatory effects on
GLUT4, cellular ATP level, and the pleiotropic factor IGF-1. A succinct summary on these studies is given in this
chapter.
