title: Growth hormone replacement therapy prevents sarcopenia by a dual mechanism: improvement of protein balance and of antioxidant defenses.
abstract: The aim of our study was to elucidate the role of growth hormone (GH) replacement therapy in three of the main mechanisms involved in sarcopenia: alterations in mitochondrial biogenesis, increase in oxidative stress, and alterations in protein balance. We used young and old Wistar rats that received either placebo or low doses of GH to reach normal insulin-like growth factor-1 values observed in the young group. We found an increase in lean body mass and plasma and hepatic insulin-like growth factor-1 levels in the old animals treated with GH. We also found a lowering of age-associated oxidative damage and an induction of antioxidant enzymes in the skeletal muscle of the treated animals. GH replacement therapy resulted in an increase in the skeletal muscle protein synthesis and mitochondrial biogenesis pathways. This was paralleled by a lowering of inhibitory factors in skeletal muscle regeneration and in protein degradation. GH replacement therapy prevents sarcopenia by acting as a double-edged sword, antioxidant and hypertrophic.
authors.affiliation: Department of Physiology, University of Valencia, Fundacion Investigacion Hospital Clinico Universitario/INCLIVA, Spain. Laboratory "Movement Sport and Health Sciences," University Rennes, France.
authors.forename: T
authors.initials: T
authors.lastname: Brioche
authors.affiliation: Department of Physiology, University Complutense of Madrid, Spain.
authors.forename: R A
authors.initials: RA
authors.lastname: Kireev
authors.affiliation: Department of Physiology, University Complutense of Madrid, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Cuesta
authors.affiliation: Laboratory "Movement Sport and Health Sciences," University Rennes, France.
authors.forename: A
authors.initials: A
authors.lastname: Gratas-Delamarche
authors.affiliation: Department of Physiology, University Complutense of Madrid, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Tresguerres
authors.affiliation: Department of Physiology, University of Valencia, Fundacion Investigacion Hospital Clinico Universitario/INCLIVA, Spain.
authors.forename: M C
authors.initials: MC
authors.lastname: Gomez-Cabrera
authors.affiliation: Department of Physiology, University of Valencia, Fundacion Investigacion Hospital Clinico Universitario/INCLIVA, Spain. jose.vina@uv.es.
authors.forename: J
authors.initials: J
authors.lastname: Viña
mesh_terms: D000375:Aging / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001823:Body Composition; D013006:Growth Hormone / Q000494:pharmacology / Q000627:therapeutic use*; D020249:Hormone Replacement Therapy; D008297:Male; D008931:Mitochondria, Muscle / Q000502:physiology; D018482:Muscle, Skeletal / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D055948:Sarcopenia / Q000517:prevention & control*
chemical_list: D000975:Antioxidants; D011506:Proteins; D013006:Growth Hormone
keywords: IGF-1.; Mitochondrial biogenesis; Myostatin; p70S6K