Exercise is mitochondrial medicine for muscle

Abstract

Mitochondria are vital organelles that provide energy for muscle function. When these organelles become dysfunctional, they produce less energy as well as excessive levels of reactive oxygen species which can trigger muscle atrophy, weakness and loss of endurance. In this review, molecular evidence is provided to show that exercise serves as a useful therapeutic countermeasure to overcome mitochondrial dysfunction, even when key regulators of organelle biogenesis are absent. These findings illustrate the complexity and compensatory nature of exercise-induced molecular signaling to transcription, as well as to post-transcriptional events within the mitochondrial synthesis and degradation (i.e. turnover) pathways. Beginning with the first bout of contractile activity, exercise exerts a medicinal effect to improve mitochondrial health and whole muscle function.

Keywords

Mitochondria / Muscle / Exercise / Health / Aging / Metabolism / Training

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The work was funded by Natural Sciences and Engineering Research Council (NSERC) and Canadian Institutes of Health Research (CIHR) grants to D.A.H. A.N.O. is the recipient of an NSERC CGS-D. D.A.H. is the recipient of a Canada Research Chair in Cell Physiology.