Altered relaxation and Mitochondria-Endoplasmic Reticulum Contacts Precede Major (Mal)adaptations in Aging Skeletal Muscle and are Prevented by Exercise.

ABSTRACT: Sarcopenia, or age-related muscle dysfunction, contributes to morbidity and mortality. Besides decreases in muscle force, sarcopenia is associated with atrophy and fast-to-slow fiber type switching, which is typically secondary to denervation in humans and rodents. However, very little is known about cellular changes preceding these important (mal)adaptations. To this matter, mitochondria and the sarcoplasmic reticulum are critical for tension generation in myofibers. They physically interact at the boundaries of sarcomeres forming subcellular hubs called mitochondria-endo/sarcoplasmic reticulum contacts (MERCs). Yet, whether changes at MERCs ultrastructure and proteome occur early in aging is unknown. Here, studying young adult and older mice we reveal that aging slows muscle relaxation l

SUBMITTER: Allen RJ 

PROVIDER: S-EPMC11838400 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature