Brief intense interval exercise activates AMPK and p38 MAPK signaling and increases the expression of PGC-1α in human skeletal muscle
Gibala, Martin J., McGee, Sean L, Garnham, Andrew P., Howlett, Kirsten F., Snow, Rodney J. and Hargreaves, Mark 2009, Brief intense interval exercise activates AMPK and p38 MAPK signaling and increases the expression of PGC-1α in human skeletal muscle, Journal of applied physiology, vol. 106, pp. 929-934.
Title
Brief intense interval exercise activates AMPK and p38 MAPK signaling and increases the expression of PGC-1α in human skeletal muscle
From a cell signaling perspective, short-duration intense muscularwork is typically associated with resistance training and linkedto pathways that stimulate growth. However, brief repeated sessionsof sprint or high-intensity interval exercise induce rapid phenotypicchanges that resemble traditional endurance training. We testedthe hypothesis that an acute session of intense intermittentcycle exercise would activate signaling cascades linked to mitochondrialbiogenesis in human skeletal muscle. Biopsies (vastus lateralis)were obtained from six young men who performed four 30-s "allout" exercise bouts interspersed with 4 min of rest (<80kJ total work). Phosphorylation of AMP-activated protein kinase(AMPK; subunits 1 and 2) and the p38 mitogen-activated proteinkinase (MAPK) was higher (P 0.05) immediately after bout 4vs. preexercise. Peroxisome proliferator-activated receptor-coactivator-1(PGC-1) mRNA was increased approximately twofoldabove rest after 3 h of recovery (P 0.05); however, PGC-1proteincontent was unchanged. In contrast, phosphorylation of proteinkinase B/Akt (Thr308 and Ser473) tended to decrease, and downstreamtargets linked to hypertrophy (p70 ribosomal S6 kinase and 4Ebinding protein 1) were unchanged after exercise and recovery.We conclude that signaling through AMPK and p38 MAPK to PGC-1may explain in part the metabolic remodeling induced by low-volumeintense interval exercise, including mitochondrial biogenesisand an increased capacity for glucose and fatty acid oxidation.