title: Gene expression is differentially regulated in skeletal muscle and circulating immune cells in response to an acute bout of high-load strength exercise.
abstract: BACKGROUND
  High-intensity exercise induces many metabolic responses. In is unknown whether the response in the peripheral blood mononuclear cells (PBMCs) reflects the response in skeletal muscle and whether mRNA expression after exercise can be modulated by nutritional intake. The aims were to (i) investigate the effect of dairy proteins on acute responses to exercise in skeletal muscle and PBMCs measuring gene expression and (ii) compare this response in young and older subjects.
  
  
  METHODS
  We performed two separate studies in young (20-40 years) and older subjects (≥70 years). Subjects were randomly allocated to a milk group or a whey group. Supplements were provided immediately after a standardized exercise session. We measured mRNA expression of selected genes after a standardized breakfast and 60/120 min after finishing the exercise, using RT-qPCR.
  
  
  RESULTS
  We observed no significant differences in mRNA expression between the milk and the whey group; thus, we merged both groups for further analysis. The mRNA expression ofIL6,TNF, andCCL2in skeletal muscle increased significantly after exercise compared with smaller or no increase, in mRNA expression in PBMCs in all participants. The mRNA expression ofIL1RN,IL8, andIL10increased significantly in skeletal muscle and PBMCs. Some mRNA transcripts were differently regulated in older compared to younger participants in PBMCs.
  
  
  CONCLUSIONS
  An acute bout of heavy-load strength exercise, followed by protein supplementation, caused overlapping, but also unique, responses in skeletal muscle and PBMCs, suggesting tissue-specific functions in response to exercise. However, no different effects of the different protein supplements were observed. Altered mRNA expressions in PBMCs of older participants may affect regenerative mechanisms.
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, P.O. Box 1046, Blindern, 0317 Norway.|Centre for Research and Development, TINE SA, P.O. Box 7, Kalbakken, 0902 Oslo Norway.
authors.forename: Gyrd O
authors.initials: GO
authors.lastname: Gjevestad
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, P.B. 4104 USA, 0806 Oslo, Norway.
authors.forename: Håvard
authors.initials: H
authors.lastname: Hamarsland
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, P.B. 4104 USA, 0806 Oslo, Norway.
authors.forename: Truls
authors.initials: T
authors.lastname: Raastad
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, P.O. Box 1046, Blindern, 0317 Norway.
authors.forename: Inger
authors.initials: I
authors.lastname: Ottestad
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, P.O. Box 1046, Blindern, 0317 Norway.|The Lipid Clinic, Oslo University Hospital Rikshospitalet, P.O. Box 4950, Nydalen, 0424 Oslo Norway.
authors.forename: Jacob J
authors.initials: JJ
authors.lastname: Christensen
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, P.O. Box 1046, Blindern, 0317 Norway.
authors.forename: Kristin
authors.initials: K
authors.lastname: Eckardt
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, P.O. Box 1046, Blindern, 0317 Norway.
authors.forename: Christian A
authors.initials: CA
authors.lastname: Drevon
authors.affiliation: Centre for Research and Development, TINE SA, P.O. Box 7, Kalbakken, 0902 Oslo Norway.
authors.forename: Anne S
authors.initials: AS
authors.lastname: Biong
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, P.O. Box 1046, Blindern, 0317 Norway.
authors.forename: Stine M
authors.initials: SM
authors.lastname: Ulven
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, P.O. Box 1046, Blindern, 0317 Norway.|National Advisory Unit on Familial Hypercholesterolemia, Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, P.O. Box 4950, Nydalen, 0424 Oslo Norway.
authors.forename: Kirsten B
authors.initials: KB
authors.lastname: Holven
keywords: Cytokines; Muscle regeneration; Peripheral blood mononuclear cells; Resistance exercise; Skeletal muscle; mRNA