Abstract
Background: Several mitochondrial abnormalities such as defective energy production, depletion of energy stores, Ca(2+) accumulation, generation of reactive oxygen species, and impaired intracellular signaling are associated with cardiac dysfunction during the development of different heart diseases. Methods: A narrative review was compiled by a search for applicable literature in MEDLINE via PubMed. Results: Mitochondria generate ATP through the processes of electron transport and oxidative phosphorylation, which is used as energy for cardiac contractile function. Mitochondria, in fact, are the key subcellular organelle for the regulation of intracellular Ca(2+) concentration and are considered to serve as a buffer to maintain Ca(2+) homeostasis in cardiomyocytes. However, during the development of heart disease, the excessive accumulation of intracellular Ca(2+) results in mitochondria Ca(2+)-overload, which, in turn, impairs mitochondrial energy production and induces cardiac dysfunction. Mitochondria also generate reactive oxygen species (ROS), including superoxide anion radicals and hydroxyl radicals as well as non-radical oxidants such as hydrogen peroxide, which promote lipid peroxidation and the subsequent disturbance of Ca(2+) homeostasis, cellular damage, and death. Conclusion: These observations support the view that both oxidative stress and intracellular Ca(2+)-overload play a critical role in mitochondrial disruption during the pathogenesis of different cardiac pathologies.