Exaggerated expression of skeletal muscle-derived interleukin-6, but not TNFalpha, in mice lacking interleukin-10.
IL-10 reduces cytokine expression in non-muscle tissues, but its effect on skeletal muscle remains undefined. Therefore, we tested the hypothesis that endogenous IL-10 acts to reduce cytokines in the gastrocnemius muscle by comparing IL-6 and TNFalpha expression in wild-type (IL-10(+/+)) and IL-10 deficient (IL-10(-/-)) mice following an inflammatory insult induced by peripheral LPS. IL-6 mRNA expression increased following LPS for both IL-10(+/+) and IL-10(-/-) mice; the response was greater and prolonged in IL-10(-/-) mice. Muscle TNFalpha mRNA also increased, but without differences between genotypes. IL-6 protein concentrations were elevated by LPS with a greater and prolonged response for IL-10(-/-) mice, but TNFalpha did not change. These results provide the first in vivo evidence that endogenous IL-10 attenuates IL-6 expression by skeletal muscle in response to LPS.
Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA. khuey@uiuc.edu
Kimberly A
KA
Huey
Robert H
RH
McCusker
Keith W
KW
Kelley
D000818:Animals; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression / Q000276:immunology; D007249:Inflammation / Q000139:chemically induced* / Q000276:immunology / Q000378:metabolism; D016753:Interleukin-10 / Q000172:deficiency*; D015850:Interleukin-6 / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000633:toxicity; D008297:Male; D051379:Mice; D008817:Mice, Mutant Strains; D018482:Muscle, Skeletal / Q000276:immunology* / Q000378:metabolism; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
D015850:Interleukin-6; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10