Mitochondrial respiratory capacity and coupling control decline with age in human skeletal muscle.
Am J Physiol Endocrinol Metab
; 309(3): E224-32, 2015 Aug 01.
Article
en En
| MEDLINE
| ID: mdl-26037248
ABSTRACT
Mitochondrial health is critical to physiological function, particularly in tissues with high ATP turnover, such as striated muscle. It has been postulated that derangements in skeletal muscle mitochondrial function contribute to impaired physical function in older adults. Here, we determined mitochondrial respiratory capacity and coupling control in skeletal muscle biopsies obtained from young and older adults. Twenty-four young (28 ± 7 yr) and thirty-one older (62 ± 8 yr) adults were studied. Mitochondrial respiration was determined in permeabilized myofibers from the vastus lateralis after the addition of substrates oligomycin and CCCP. Thereafter, mitochondrial coupling control was calculated. Maximal coupled respiration (respiration linked to ATP production) was lower in muscle from older vs. young subjects (P < 0.01), as was maximal uncoupled respiration (P = 0.06). Coupling control in response to the ATP synthase inhibitor oligomycin was lower in older adults (P < 0.05), as was the mitochondria flux control ratio, coupled respiration normalized to maximal uncoupled respiration (P < 0.05). Calculation of respiratory function revealed lower respiration linked to ATP production (P < 0.001) and greater reserve respiration (P < 0.01); i.e., respiratory capacity not used for phosphorylation in muscle from older adults. We conclude that skeletal muscle mitochondrial respiratory capacity and coupling control decline with age. Lower respiratory capacity and coupling efficiency result in a reduced capacity for ATP production in skeletal muscle of older adults.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Fosforilación Oxidativa
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Envejecimiento
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Regulación hacia Abajo
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Músculo Esquelético
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Complejo I de Transporte de Electrón
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Complejo II de Transporte de Electrones
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Mitocondrias Musculares
Tipo de estudio:
Clinical_trials
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Etiology_studies
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Incidence_studies
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Observational_studies
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Risk_factors_studies
Límite:
Adult
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Aged
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Aged80
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Año:
2015
Tipo del documento:
Article