Energy-dissipating hub in muscle mitochondria: Potassium channels and uncoupling proteins.

Energy homeostasis in mitochondria is vital for proper muscle cell function. In this review we will focus on cardiac and skeletal muscle energy-dissipating systems, i.e., mitochondrial potassium channels and uncoupling proteins. Despite the molecular differences between these proteins both of them may regulate the generation of reactive oxygen species. Hence, they can both modulate pro-life and -death signaling in response to the needs of the muscle cell. Certain mitochondrial potassium channels (such as the ATP-regulated and large conductance calcium-activated mitochondrial potassium channels) and uncoupling proteins may be regulated in a similar manner suggesting that both are part of the energy-dissipating hub in muscle mitochondria. Understanding the role of these proteins, especially in the context of ischemia-reperfusion injury of cardiac muscle, may be important for pharmacological intervention. This review highlights several aspects of the regulation of mitochondrial potassium channels and uncoupling proteins in muscle mitochondria and their association with diseases.