Effect of exercise, training, and glycogen availability on IL-6 receptor expression in human skeletal muscle

• Published in: Journal of applied physiology (1985) 2005-12, Vol.99 (6), p.2075-2079
• Main Authors: Keller, Charlotte, Steensberg, Adam, Hansen, Anne K, Fischer, Christian P, Plomgaard, Peter, Pedersen, Bente Klarlund
• Format: Article
• Language: English
• Subjects: Adaptation, Physiological - physiology; Adult; Biological and medical sciences; Cytokines; Exercise; Exercise - physiology; Fundamental and applied biological sciences. Psychology; Gene expression; Gene Expression Regulation - physiology; Glycogen - metabolism; Humans; Male; Muscle, Skeletal - physiology; Muscular system; Physical Exertion - physiology; Physical Fitness - physiology; Receptors, Interleukin-6 - metabolism
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.00590.2005

Centre of Inflammation and Metabolism, Department of Infectious Diseases and the Copenhagen Muscle Research Centre, Rigshospitalet, and Faculty of Health Sciences, University of Copenhagen, Denmark Submitted 19 May 2005 ; accepted in final form 3 August 2005 The cytokine interleukin-6 (IL-6) exerts it actions via the IL-6 receptor (IL-6R) in conjunction with the ubiquitously expressed gp130 receptor. IL-6 is tightly regulated in response to exercise, being affected by factors such as exercise intensity and duration, as well as energy availability. Although the IL-6 response to exercise has been extensively studied, little is known about the regulation of the IL-6R response. In the present study, we aimed to investigate the effect of exercise, training, and glycogen availability, factors known to affect IL-6, on the regulation of gene expression of the IL-6R in human skeletal muscle. Human subjects performed either 10 wk of training with an acute exercise bout before and after the training period, or a low-glycogen vs. normal-glycogen acute exercise trial. The IL-6R mRNA response was evaluated in both trials. In response to acute exercise, an increase in IL-6R mRNA levels was observed. Neither training nor intramuscular glycogen levels had an effect on the IL-6R mRNA response to exercise. However, after 10 wk of training, the skeletal muscle expressed a higher mRNA level of IL-6R compared with before training. The present study demonstrated that the IL-6R gene expression levels in skeletal muscle are increased in response to acute exercise, a response that is very well conserved, being affected by neither training status nor intramuscular glycogen levels, as opposed to IL-6. However, after the training period, IL-6R mRNA production was increased in skeletal muscle, suggesting a sensitization of skeletal muscle to IL-6 at rest. interleukin-6 receptor Address for reprint requests and other correspondence: C. Keller, Copenhagen Muscle Research Centre, Rigshospitalet, Section 7652, Tagensvej 20, DK-2200, Copenhagen N, Denmark (e-mail: ckeller{at}inflammation-metabolism.dk )