Trevino 2019 Am J Physiol Endocrinol Metab
|Trevino MB, Zhang X, Standley RA, Wang M, Han X, Reis FCG, Periasamy M1, Yu G, Kelly DP, Goodpaster BH, Vega RB, Coen PM (2019) Loss of mitochondrial energetics is associated with poor recovery of muscle function but not mass following disuse atrophy. Am J Physiol Endocrinol Metab 317:E899-910.|
Abstract: Skeletal muscle atrophy is a clinically important outcome of disuse due to injury, immobilization and bed rest. Disuse atrophy is accompanied by mitochondrial dysfunction which likely contributes to activation of the muscle atrophy program. However, the linkage of muscle mass and mitochondrial energetics, during disuse atrophy and its recovery is incompletely understood. Transcriptomic analysis of muscle biopsies from healthy older adults subject to complete bed rest revealed marked inhibition of mitochondrial energy metabolic pathways. To determine the temporal sequence of muscle atrophy, and changes in intramyocellular lipid and mitochondrial energetics, we conducted a time course of hind limb unloading induced atrophy in adult mice. Mitochondrial respiration and calcium retention capacity were diminished while H2O2 emission was increased in as soon as 3 days of unloading, prior to significant muscle atrophy. These changes were associated with a decrease in total cardiolipin and profound changes in remodeled cardiolipin species. Hindlimb unloading performed in muscle-specific PGC-1α/β knockout mice, a model of mitochondrial dysfunction, did not affect muscle atrophy but impacted muscle function. These data suggest early mitochondrial remodeling affects muscle function but not mass during disuse atrophy. Early alterations in mitochondrial energetics and lipid remodeling may represent novel targets to prevent muscle functional impairment caused by disuse and to enhance recovery from periods of muscle atrophy.
Labels: MiParea: Respiration, Genetic knockout;overexpression, Exercise physiology;nutrition;life style
Organism: Mouse Tissue;cell: Skeletal muscle Preparation: Permeabilized tissue
Coupling state: LEAK, OXPHOS Pathway: N, NS HRR: Oxygraph-2k
Labels, 2019-10, CN, US