2026-07-26T08:13:03Zhttps://repisalud.isciii.es/rest/oai/request

oai:repisalud.isciii.es:20.500.12105/275992026-07-17T00:17:40Zcom_20.500.12105_19586com_20.500.12105_2202col_20.500.12105_19587

00925njm 22002777a 4500 dc García-Domínguez, Esther author García-Domínguez, Cristina author Cabrera-Alarcón, José Luis author Muñoz-Hernández, María Del Mar author Hernansanz-Agustín, Pablo author Curtabbi, Andrea author Domenech-Fernandez, Julio author Calvo, Enrique author Vázquez, Jesús author Serrano, Antonio L author Muñoz-Cánoves, Pura author Olaso-González, Gloria author Enríquez, José Antonio author Gómez-Cabrera, María Carmen author 2026-04-07 Loss of skeletal muscle mass and strength are common manifestations of frailty in older people and are linked to reduced quality of life. However, whether mitochondria are mechanistically linked to frailty and how physical activity, or lack thereof, is involved in age-related functional decline are still unknown. We report that exercise-induced improvements in functional capacity, including reduced frailty in old mice, are dependent on mitochondrial adaptations in skeletal muscle at structural, enzymatic, and functional levels. Our preclinical study included a healthy aging mouse line, a transgenic model of robustness, and a muscle-specific mitochondrial-deficient mutant mice, allowing us to assess both mitochondrial plasticity with aging and the necessity of intact mitochondrial function for exercise-induced adaptations. These findings were corroborated by a cross-sectional human study examining the relationship between skeletal muscle mitochondrial function, age, and physical capacity. We analyzed biopsies from 30 donors (men and women, aged 17 to 99 y) stratified into young and older adults with varying functional statuses. Our results indicate that mitochondrial dysfunction in skeletal muscle is associated with the decline in locomotor muscle function in the elderly, highlighting the potential role of exercise or habitual physical activity in mitigating this phenotype. Notably, we demonstrate that skeletal muscle mitochondria maintain plasticity during aging in mice and humans, and that this preserved adaptability can be leveraged to improve muscle performance and overall functional capacity. Proc Natl Acad Sci USA. 2026 Apr 7;123(14):e2508286123. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 41911459 https://hdl.handle.net/20.500.12105/27599 frailty health span mitochondrial function proteomics sarcopenia Mitochondrial remodeling in skeletal muscle underlies exercise-induced reversal of age-associated functional decline in mice and humans.