The Paper of the Week for 9 March 2012 was entitled "Acute Exercise Remodels Promoter Methylation in Human Skeletal Muscle" by Barres, et al. It appeared in Cell Metabolism as a Short Article.
The exercise test was performed on a stationary bicycle. One cohort of subjects were exercised until reaching either 40% or 80% of VO2 peak. A second cohort was exercised until 1,674 kJ were expended. These were acute interventions, making the findings all the more remarkable.
I found the following to be key points of this paper:
1. In both healthy, sedentary women and men, it was observed that whole genome methylation was decreased in skeletal muscle.
2. While exercise induced expression of PPARGC1A (PGC-1α), PDK4, and PPARD, the authors also noted reduced methylation at each of the promoters for these genes.
PPARGC1A is a key transcriptional regulator of OXPHOS (oxidative phosphorylation) genes. It is also an important type 2 diabetes gene.