title: Myostatin in relation to physical activity and dysglycaemia and its effect on energy metabolism in human skeletal muscle cells.
abstract: OBJECTIVE
  Some health benefits of exercise may be explained by an altered secretion of myokines. Because previous focus has been on upregulated myokines, we screened for downregulated myokines and identified myostatin. We studied the expression of myostatin in relation to exercise and dysglycaemia in skeletal muscle, adipose tissue and plasma. We further examined some effects of myostatin on energy metabolism in primary human muscle cells and Simpson-Golabi-Behmel syndrome (SGBS) adipocytes.
  
  
  METHODS
  Sedentary men with or without dysglycaemia underwent a 45-min acute bicycle test before and after 12 weeks of combined endurance and strength training. Blood samples and biopsies from m. vastus lateralis and adipose tissue were collected.
  
  
  RESULTS
  Myostatin mRNA expression was reduced in skeletal muscle after acute as well as long-term exercise and was even further downregulated by acute exercise on top of 12-week training. Furthermore, the expression of myostatin at baseline correlated negatively with insulin sensitivity. Myostatin expression in the adipose tissue increased after 12 weeks of training and correlated positively with insulin sensitivity markers. In cultured muscle cells but not in SGBS cells, myostatin promoted an insulin-independent increase in glucose uptake. Furthermore, muscle cells incubated with myostatin had an enhanced rate of glucose oxidation and lactate production.
  
  
  CONCLUSIONS
  Myostatin was differentially expressed in the muscle and adipose tissue in relation to physical activity and dysglycaemia. Recombinant myostatin increased the consumption of glucose in human skeletal muscle cells, suggesting a complex regulatory role of myostatin in skeletal muscle homeostasis.
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: M
authors.initials: M
authors.lastname: Hjorth
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: S
authors.initials: S
authors.lastname: Pourteymour
authors.affiliation: Paul-Langerhans-Group for Integrative Physiology, German Diabetes Center, Düsseldorf, Germany.
authors.forename: S W
authors.initials: SW
authors.lastname: Görgens
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.|Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital and Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: T M
authors.initials: TM
authors.lastname: Langleite
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: S
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: T
authors.initials: T
authors.lastname: Holen
authors.affiliation: Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital and Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: H L
authors.initials: HL
authors.lastname: Gulseth
authors.affiliation: Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital and Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: K I
authors.initials: KI
authors.lastname: Birkeland
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway.
authors.forename: J
authors.initials: J
authors.lastname: Jensen
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: C A
authors.initials: CA
authors.lastname: Drevon
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: F
authors.initials: F
authors.lastname: Norheim
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac; D001786:Blood Glucose / Q000502:physiology; D015153:Blotting, Western; D015536:Down-Regulation; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D040181:Genetic Diseases, X-Linked; D005877:Gigantism; D005947:Glucose / Q000378:metabolism; D015309:Glucose Clamp Technique; D006330:Heart Defects, Congenital; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology; D008607:Intellectual Disability; D008297:Male; D008875:Middle Aged; D032342:Muscle Cells / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D055435:Myostatin / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D001786:Blood Glucose; D055435:Myostatin; D005947:Glucose
keywords: adipocytes; adipose tissue; exercise; myostatin; physical activity; skeletal muscle