title: Skeletal muscle lipid content and oxidative activity in relation to muscle fiber type in aging and metabolic syndrome.
abstract: One of the most noticeable effects of aging is the reduction in skeletal muscle mass and strength (sarcopenia). The metabolic syndrome (MS) is also prevalent in old subjects, but its relevance to skeletal muscle characteristics has poorly been investigated. Immunohistochemical studies were performed with muscle biopsies from young (22 years) and old (73 years) men with and without MS to reveal age-dependent and MS-associated modifications of fiber-type characteristics. Atrophy of type II fibers and altered fiber shape characterized muscle aging in lean healthy men. In contrast, increased cross-sectional area of the most abundant type I and type IIA fibers, and reduced cytochrome c oxidase content in all fiber types, characterized MS. Aging and particularly MS were associated with accumulation of intramyocellular lipid droplets. Although lipids mostly accumulated in type I fibers, matrix-assisted laser desorption/ionization-mass spectrometry imaging of intramyocellular lipids did not distinguish fiber types, but clearly separated young, old, and MS subjects. In conclusion, our study suggests that MS in the elderly persons is associated with alterations in skeletal muscle at a fiber-type specific level. Overall, these fiber type-specific modifications may be important both for the age-related loss of muscle mass and strength and for the increased prevalence of MS in elderly subjects.
authors.affiliation: INRA, UMR1019, Unité de Nutrition Humaine, CRNH Auvergne, Saint Genès Champanelle, France. Clermont Université, Université d'Auvergne, Clermont-Ferrand, France.
authors.forename: Marine
authors.initials: M
authors.lastname: Gueugneau
authors.affiliation: INRA, UMR1019, Unité de Nutrition Humaine, CRNH Auvergne, Saint Genès Champanelle, France. Clermont Université, Université d'Auvergne, Clermont-Ferrand, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Coudy-Gandilhon
authors.affiliation: INRA, UMR1019, Unité de Nutrition Humaine, CRNH Auvergne, Saint Genès Champanelle, France. INRA, Plateforme d'Exploration du Métabolisme Composante Protéomique, Saint Genès Champanelle, France.
authors.forename: Laëtitia
authors.initials: L
authors.lastname: Théron
authors.affiliation: INRA-Vetagro Sup, UMR 1213, Unité Mixte de Recherche sur les Herbivores, Saint Genès Champanelle, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Meunier
authors.affiliation: INRA-Vetagro Sup, UMR 1213, Unité Mixte de Recherche sur les Herbivores, Saint Genès Champanelle, France.
authors.forename: Christiane
authors.initials: C
authors.lastname: Barboiron
authors.affiliation: INRA, UMR1019, Unité de Nutrition Humaine, CRNH Auvergne, Saint Genès Champanelle, France. Clermont Université, Université d'Auvergne, Clermont-Ferrand, France.
authors.forename: Lydie
authors.initials: L
authors.lastname: Combaret
authors.affiliation: INRA, UMR1019, Unité de Nutrition Humaine, CRNH Auvergne, Saint Genès Champanelle, France. Clermont Université, Université d'Auvergne, Clermont-Ferrand, France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Taillandier
authors.affiliation: INRA, UMR1019, Unité de Nutrition Humaine, CRNH Auvergne, Saint Genès Champanelle, France. Clermont Université, Université d'Auvergne, Clermont-Ferrand, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Polge
authors.affiliation: INRA, UMR1019, Unité de Nutrition Humaine, CRNH Auvergne, Saint Genès Champanelle, France. Clermont Université, Université d'Auvergne, Clermont-Ferrand, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Attaix
authors.affiliation: INRA-Vetagro Sup, UMR 1213, Unité Mixte de Recherche sur les Herbivores, Saint Genès Champanelle, France.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Picard
authors.affiliation: Unité de Myologie, Centre Référent Maladies Neuromusculaires Rares Rhône-Alpes, CHU de St Etienne Laboratoire de Physiologie de l'Exercice EA4338, Université Jean Monnet de St Etienne, Université de Lyon, Saint-Etienne, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Verney
authors.affiliation: Service de Physiologie Clinique et de l'Exercice, CHU Nord, Faculté de Médecine Jacques Lisfranc, PRES de Lyon, Université Jean Monnet, Saint-Etienne, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Roche
authors.affiliation: Unité de Myologie, Centre Référent Maladies Neuromusculaires Rares Rhône-Alpes, CHU de St Etienne Laboratoire de Physiologie de l'Exercice EA4338, Université Jean Monnet de St Etienne, Université de Lyon, Saint-Etienne, France.
authors.forename: Léonard
authors.initials: L
authors.lastname: Féasson
authors.affiliation: Service de Physiologie Clinique et de l'Exercice, CHU Nord, Faculté de Médecine Jacques Lisfranc, PRES de Lyon, Université Jean Monnet, Saint-Etienne, France.
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Barthélémy
authors.affiliation: INRA, UMR1019, Unité de Nutrition Humaine, CRNH Auvergne, Saint Genès Champanelle, France. Clermont Université, Université d'Auvergne, Clermont-Ferrand, France. daniel.bechet@clermont.inra.fr.
authors.forename: Daniel
authors.initials: D
authors.lastname: Béchet
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D000375:Aging / Q000378:metabolism*; D001706:Biopsy; D001823:Body Composition / Q000502:physiology; D003576:Electron Transport Complex IV / Q000378:metabolism; D004734:Energy Metabolism / Q000502:physiology; D006801:Humans; D050356:Lipid Metabolism / Q000502:physiology*; D008297:Male; D024821:Metabolic Syndrome / Q000378:metabolism*; D018485:Muscle Fibers, Skeletal / Q000378:metabolism*; D053580:Muscle Strength / Q000502:physiology; D055948:Sarcopenia / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D055815:Young Adult
chemical_list: D003576:Electron Transport Complex IV
keywords: Aging; Fiber types; Lipid droplets; Metabolic syndrome; Skeletal muscle.