TY - JOUR

T1 - Endurance training enhances skeletal muscle interleukin-15 in human male subjects

AU - Rinnov, Anders

AU - Yfanti, Christina

AU - Nielsen, Søren

AU - Åkerstrøm, Thorbjørn

AU - Peijs, Lone

AU - Zankari, Alaa

AU - Fischer, Christian P

AU - Pedersen, Bente K

PY - 2014/3

Y1 - 2014/3

N2 - Regular endurance exercise promotes metabolic and oxidative changes in skeletal muscle. Overexpression of interleukin-15 (IL-15) in mice exerts similar metabolic changes in muscle as seen with endurance exercise. Muscular IL-15 production has been shown to increase in mice after weeks of regular endurance running. With the present study we aimed to determine if muscular IL-15 production would increase in human male subjects following 12 weeks of endurance training. In two different studies we obtained plasma and muscle biopsies from young healthy subjects performing: (1) 12 weeks of ergometer cycling exercise five times per week with plasma and biopsies before and after the intervention, and (2) 3 h of ergometer cycling exercise with plasma and biopsies before and after the exercise bout and well into recovery. We measured changes in plasma IL-15, muscle IL-15 mRNA and IL-15 protein. Twelve weeks of regular endurance training induced a 40% increase in basal skeletal muscle IL-15 protein content (p < 0.01), but with no changes in either muscle IL-15 mRNA or plasma IL-15 levels. However, an acute bout of 3-h exercise did not show significant changes in muscle IL-15 or plasma IL-15 levels. The induction of muscle IL-15 protein in humans following a regular training period supports previous findings in mice and emphasizes the hypothesis of IL-15 taking part in skeletal muscle adaptation during training.

AB - Regular endurance exercise promotes metabolic and oxidative changes in skeletal muscle. Overexpression of interleukin-15 (IL-15) in mice exerts similar metabolic changes in muscle as seen with endurance exercise. Muscular IL-15 production has been shown to increase in mice after weeks of regular endurance running. With the present study we aimed to determine if muscular IL-15 production would increase in human male subjects following 12 weeks of endurance training. In two different studies we obtained plasma and muscle biopsies from young healthy subjects performing: (1) 12 weeks of ergometer cycling exercise five times per week with plasma and biopsies before and after the intervention, and (2) 3 h of ergometer cycling exercise with plasma and biopsies before and after the exercise bout and well into recovery. We measured changes in plasma IL-15, muscle IL-15 mRNA and IL-15 protein. Twelve weeks of regular endurance training induced a 40% increase in basal skeletal muscle IL-15 protein content (p < 0.01), but with no changes in either muscle IL-15 mRNA or plasma IL-15 levels. However, an acute bout of 3-h exercise did not show significant changes in muscle IL-15 or plasma IL-15 levels. The induction of muscle IL-15 protein in humans following a regular training period supports previous findings in mice and emphasizes the hypothesis of IL-15 taking part in skeletal muscle adaptation during training.

KW - Adaptation, Physiological

KW - Adult

KW - Biopsy

KW - Exercise

KW - Exercise Test

KW - Humans

KW - Interleukin-15

KW - Male

KW - Muscle, Skeletal

KW - Physical Endurance

KW - RNA, Messenger

KW - Time Factors

KW - Up-Regulation

U2 - 10.1007/s12020-013-9969-z

DO - 10.1007/s12020-013-9969-z

M3 - Journal article

C2 - 23649460

VL - 45

SP - 271

EP - 278

JO - Endocrine

JF - Endocrine

SN - 1355-008X

IS - 2

ER -