Transcriptional activation of the IL-6 gene in human contracting skeletal muscle: influence of muscle glycogen content.


Journal Article

In humans, the plasma interleukin 6 (IL-6) concentration increases dramatically during low-intensity exercise. Measurements across the working limb indicate that skeletal muscle is the source of IL-6 production. To determine whether energy availability influences the regulation of IL-6 expression during prolonged exercise, six male subjects completed two trials consisting of 180 min of two-legged dynamic knee extensor with either normal or low (~60% of control) pre-exercise muscle glycogen levels. Increases in plasma IL-6 during exercise were significantly higher (P<0.05) in the low-glycogen (16-fold) trial verses the control (10-fold) trial. Transcriptional activation of the IL-6 gene in skeletal muscle was also higher in the low-glycogen trial; it increased by about 40-fold after 90 min of exercise and about 60-fold after 180 min of exercise. Muscle IL-6 mRNA followed a similar but delayed pattern, increasing by more than 100-fold in the low-glycogen trial and by about 30-fold in the control trial. These data demonstrate that exercise activates transcription of the IL-6 gene in working skeletal muscle, a response that is dramatically enhanced when glycogen levels are low. These findings also support the hypothesis that IL-6 may be produced by contracting myofibers when glycogen levels become critically low as a means of signaling the liver to increase glucose production.

Full Text

Duke Authors

Cited Authors

  • Keller, C; Steensberg, A; Pilegaard, H; Osada, T; Saltin, B; Pedersen, BK; Neufer, PD

Published Date

  • December 2001

Published In

Volume / Issue

  • 15 / 14

Start / End Page

  • 2748 - 2750

PubMed ID

  • 11687509

Pubmed Central ID

  • 11687509

Electronic International Standard Serial Number (EISSN)

  • 1530-6860

Digital Object Identifier (DOI)

  • 10.1096/fj.01-0507fje


  • eng

Conference Location

  • United States