title: Cytokine expression and secretion by skeletal muscle cells: regulatory mechanisms and exercise effects.
abstract: Cytokines are important mediators of various aspects of health and disease, including appetite, glucose and lipid metabolism, insulin sensitivity, skeletal muscle hypertrophy and atrophy. Over the past decade or so, considerable attention has focused on the potential for regular exercise to counteract a range of disease states by modulating cytokine production. Exercise stimulates moderate to large increases in the circulating concentrations of interleukin (IL)-6, IL-8, IL- 10, IL-1 receptor antagonist, granulocyte-colony stimulating factor, and smaller increases in tumor necrosis factor-α, monocyte chemotactic protein-1, IL-1β, brain-derived neurotrophic factor, IL-12p35/p40 and IL-15. Although many of these cytokines are also expressed in skeletal muscle, not all are released from skeletal muscle into the circulation during exercise. Conversely, some cytokines that are present in the circulation are not expressed in skeletal muscle after exercise. The reasons for these discrepant cytokine responses to exercise are unclear. In this review, we address these uncertainties by summarizing the capacity of skeletal muscle cells to produce cytokines, analyzing other potential cellular sources of circulating cytokines during exercise, and discussing the soluble factors and intracellular signaling pathways that regulate cytokine synthesis (e.g., RNA-binding proteins, microRNAs, suppressor of cytokine signaling proteins, soluble receptors).
authors.affiliation: School of Biomedical Sciences and Institute of Health and Biomedical Sciences, Queensland University of Technology, Brisbane, Australia.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Peake
authors.affiliation: Centre for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Melbourne, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Della Gatta
authors.affiliation: Faculty of Sport Sciences, Waseda University, Cooperative Major in Advanced Health Science, Tokyo University of Agriculture and Technology/Waseda University, Tokorozawa, Saitama, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Suzuki
authors.affiliation: Human Performance Laboratory, Appalachian State University, North Carolina Research Campus, Kannapolis, North Carolina, USA.
authors.forename: David C
authors.initials: DC
authors.lastname: Nieman
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D015444:Exercise / Q000502:physiology*; D005347:Fibroblasts / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis / Q000097:blood / Q000378:metabolism; D009043:Motor Activity / Q000502:physiology; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000378:metabolism*; D009124:Muscle Proteins / Q000378:metabolism; D022423:Myeloid Cells / Q000378:metabolism; D032446:Myoblasts / Q000378:metabolism; D009928:Organ Specificity; D005082:Physical Exertion / Q000502:physiology*; D012333:RNA, Messenger / Q000096:biosynthesis; D016601:RNA-Binding Proteins / Q000378:metabolism; D018121:Receptors, Cytokine / Q000378:metabolism; D012420:Running / Q000502:physiology
chemical_list: D016207:Cytokines; C508600:IL6 protein, human; D015850:Interleukin-6; D009124:Muscle Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D018121:Receptors, Cytokine