Enhanced Respiratory Chain Supercomplex Formation in Response to Exercise in Human Skeletal Muscle

Cell Metab. 2017 Feb 7;25(2):301-311. doi: 10.1016/j.cmet.2016.11.004. Epub 2016 Dec 1.

Abstract

Mitochondrial dysfunction is a hallmark of multiple metabolic complications. Physical activity is known to increase mitochondrial content in skeletal muscle, counteracting age-related decline in muscle function and protecting against metabolic and cardiovascular complications. Here, we investigated the effect of 4 months of exercise training on skeletal muscle mitochondria electron transport chain complexes and supercomplexes in 26 healthy, sedentary older adults. Exercise differentially modulated respiratory complexes. Complex I was the most upregulated complex and not stoichiometrically associated to the other complexes. In contrast to the other complexes, complex I was almost exclusively found assembled in supercomplexes in muscle mitochondria. Overall, supercomplex content was increased after exercise. In particular, complexes I, III, and IV were redistributed to supercomplexes in the form of I+III2+IV. Taken together, our results provide the first evidence that exercise affects the stoichiometry of supercomplex formation in humans and thus reveal a novel adaptive mechanism for increased energy demand.

Keywords: aging; electron transport chain; endurance training; exercise intervention; human; mitochondria; pre-/post-design; respiratory complex; skeletal muscle; supercomplex.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adiposity
  • Aged
  • Aging / metabolism
  • Cell Respiration
  • Electron Transport Chain Complex Proteins / metabolism*
  • Exercise / physiology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Muscle, Skeletal / physiology*
  • Oxygen / metabolism

Substances

  • Electron Transport Chain Complex Proteins
  • Oxygen