These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Resistance exercise with low glycogen increases p53 phosphorylation and PGC-1α mRNA in skeletal muscle.
    Author: Camera DM, Hawley JA, Coffey VG.
    Journal: Eur J Appl Physiol; 2015 Jun; 115(6):1185-94. PubMed ID: 25650067.
    Abstract:
    PURPOSE: We determined the effect of reduced muscle glycogen availability on cellular pathways regulating mitochondrial biogenesis and substrate utilization after a bout of resistance exercise. METHODS: Eight young, recreationally trained men undertook a glycogen depletion protocol of one-leg cycling to fatigue (LOW), while the contralateral (control) leg rested (CONT). Following an overnight fast, subjects completed 8 sets of 5 unilateral leg press repetitions (REX) at 80 % 1 Repetition Maximum (1RM) on each leg. Subjects consumed 500 mL protein/CHO beverage (20 g whey + 40 g maltodextrin) upon completion of REX and 2 h later. Muscle biopsies were obtained at rest and 1 and 4 h after REX in both legs. RESULTS: Resting muscle glycogen was higher in the CONT than LOW leg (~384 ± 114 vs 184 ± 36 mmol kg(-1) dry wt; P < 0.05), and 1 h and 4 h post-exercise (P < 0.05). Phosphorylation of p53(Ser15) increased 1 h post-exercise in LOW (~115 %, P < 0.05) and was higher than CONT at this time point (~87 %, P < 0.05). p38MAPK(Thr180/Tyr182) phosphorylation increased 1 h post-exercise in both CONT and LOW (~800-900 %; P < 0.05) but remained above rest at 4 h only in CONT (~585 %, P < 0.05; different between legs P < 0.05). Peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) mRNA was elevated 4 h post-exercise in LOW (~200 %, P < 0.05; different between legs P < 0.05). There were no changes in Fibronectin type III domain-containing protein 5 (FNDC5) mRNA for CONT or LOW legs post-exercise. CONCLUSION: Undertaking resistance exercise with low glycogen availability may enhance mitochondrial-related adaptations through p53 and PGC-1α-mediated signalling.
    [Abstract] [Full Text] [Related] [New Search]