Description
We performed the circadian transcriptome analysis using the skeletal muscle from sedentary and exercised mice either in the early rest phase (ZT3) or in the early active phase (ZT15). By the combination with circadian transcriptomic and metabolomic analysis, we revealed time-of-day-dependent remodeling of circadian muscular metabolic pathways involved in glucose and glycerol metabolism after exercise. We found that only exercise in the early active phase elevates the levels of genes encoding glycolytic enzymes followed by the activation of fatty acid oxidation, branched-chain amino acid catabolism and ketogenesis/ketosis. This study demonstrates that time-of-day is a critical factor to modulate the impact of exercise on metabolic pathways within skeletal muscle. Overall design: Skeletal muscles from sedentary (sham-exercise) mice and mice subjected to acute treadmill exercise either in the early rest phase (ZT3) or in the early active phase (ZT15) were harvested after 0, 4, 8, 12, 16, and 20 hours after exercise or sham-exercise treatment.