title: Influence of omega-3 fatty acids on skeletal muscle protein metabolism and mitochondrial bioenergetics in older adults.
abstract: Omega-3 polyunsaturated fatty acids (n3-PUFA) are recognized for their anti-inflammatory effects and may be beneficial in the context of sarcopenia. We determined the influence of n3-PUFA on muscle mitochondrial physiology and protein metabolism in older adults. Twelve young (18-35 years) and older (65-85 years) men and women were studied at baseline. Older adults were studied again following n3-PUFA supplementation (3.9g/day, 16 weeks). Muscle biopsies were used to evaluate respiratory capacity (high resolution respirometry) and oxidant emissions (spectrofluorometry) in isolated mitochondria. Maximal respiration was significantly lower in older compared to young. n3-PUFA did not change respiration, but significantly reduced oxidant emissions. Participants performed a single bout of resistance exercise, followed by biopsies at 15 and 18 hours post exercise. Several genes involved in muscle protein turnover were significantly altered in older adults at baseline and following exercise, yet muscle protein synthesis was similar between age groups under both conditions. Following n3-PUFA supplementation, mixed muscle, mitochondrial, and sarcoplasmic protein synthesis rates were increased in older adults before exercise. n3-PUFA increased post-exercise mitochondrial and myofibrillar protein synthesis in older adults. These results demonstrate that n3-PUFA reduce mitochondrial oxidant emissions, increase postabsorptive muscle protein synthesis, and enhance anabolic responses to exercise in older adults.
authors.affiliation: Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors.forename: Antigoni Z
authors.initials: AZ
authors.lastname: Lalia
authors.affiliation: Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors.forename: Surendra
authors.initials: S
authors.lastname: Dasari
authors.affiliation: Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors.forename: Matthew M
authors.initials: MM
authors.lastname: Robinson
authors.affiliation: Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors.forename: Hinnah
authors.initials: H
authors.lastname: Abid
authors.affiliation: Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors.forename: Dawn M
authors.initials: DM
authors.lastname: Morse
authors.affiliation: Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors.forename: Katherine A
authors.initials: KA
authors.lastname: Klaus
authors.affiliation: Division of Endocrinology and Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors.forename: Ian R
authors.initials: IR
authors.lastname: Lanza
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism / Q000502:physiology*; D015308:Anaerobic Threshold / Q000187:drug effects; D004734:Energy Metabolism / Q000187:drug effects*; D015444:Exercise; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008297:Male; D008931:Mitochondria, Muscle / Q000187:drug effects*; D009124:Muscle Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D016877:Oxidants / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D012519:Sarcoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism; D055815:Young Adult
chemical_list: D015525:Fatty Acids, Omega-3; D009124:Muscle Proteins; D016877:Oxidants; D017382:Reactive Oxygen Species
keywords: DHA; EPA; mitochondria; n3-PUFA; protein synthesis; sarcopenia