Int J Sports Med 2014; 35(04): 273-279
DOI: 10.1055/s-0033-1353147
Physiology & Biochemistry
© Georg Thieme Verlag KG Stuttgart · New York

Exercise Sensitizes Skeletal Muscle to Extracellular ATP for IL-6 Expression in Mice

R. Fernández-Verdejo
1   Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
,
M. Casas
1   Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
,
J. E. Galgani
2   Departamento de Nutrición, Facultad de Medicina, Universidad de Chile, Santiago, Chile
,
E. Jaimovich
1   Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
,
S. Buvinic
1   Centro de Estudios Moleculares de la Célula, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
3   Departmento de Ciencias Básicas y Comunitarias, Facultad de Odontología, Universidad de Chile, Santiago, Chile
› Author Affiliations
Further Information

Publication History



accepted after revision 04 July 2013

Publication Date:
10 September 2013 (online)

Preview

Abstract

Active skeletal muscle synthesizes and releases interleukin-6 (IL-6), which plays important roles in the organism’s adaptation to exercise. Autocrine/paracrine ATP signaling has been shown to modulate IL-6 expression. The aim of this study was to determine whether a period of physical activity modifies the ATP-induced IL-6 expression. BalbC mice were either subject to 5 weeks voluntary wheel running (VA) or kept sedentary (SED). Flexor digitorum brevis muscles were dissected, stimulated with different ATP concentrations (0-100 μM) and IL-6 mRNA levels were measured using qPCR. ATP evoked a concentration-dependent rise in IL-6 mRNA in both SED and VA mice. VA mice however, had significantly higher ATP sensitivity (pD2 pharmacological values: VA=5.58±0.02 vs. SED=4.95±0.04, p<0.05). Interestingly, in VA mice we observed a positive correlation between the level of physical activity and the IL-6 mRNA increase following fiber stimulation with 10 μM ATP. In addition, there were lower P2Y2- and higher P2Y14-receptor mRNA levels in skeletal muscles of VA compared to SED mice, showing plasticity of nucleotide receptors with exercise. These results suggest that exercise increases skeletal muscle ATP sensitivity, a response dependent on the level of physical activity performed. This could have an important role in the mechanisms controlling skeletal muscle adaptation to exercise and training.