Mitochondria are the power plants that produce the energy (ATP) needed for our cells to function. Mitochondrial dysfunction is a hallmark of aging, and refers to a decline in the mitochondria’s ability to function, including their ability to produce energy. This happens because mitochondria accumulate damage in their genetic code, some of which is kept separate from the rest of the human genome and therefore is not as well protected.
ATP, the cell’s ‘fuel’, is required for many vital processes.
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Mitochondrial dysfunction means that there is less energy available for the cell, which may contribute to loss of function with age, particularly in tissues that require a lot of energy like muscle. In addition to producing energy, mitochondria are also important in a wide range of processes that are relevant to aging such as apoptosis (cell suicide), autophagy (the disposal of damaged cell components) inflammation and glucose metabolism. This article provides a more in-depth explanation of mitochondrial dysfunction.