Document Detail


Early time course of Akt phosphorylation after endurance and resistance exercise.
MedLine Citation:
PMID:  20195183     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
PURPOSE: The aim of this study was to determine the early time course of exercise-induced signaling after divergent contractile activity associated with resistance and endurance exercise.
METHODS: Sixteen male subjects were randomly assigned to either a cycling (CYC; n = 8, 60 min, 70% V˙O2peak) or resistance (REX; n = 8, 8 x 5 leg extension, 80% one-repetition maximum, 3-min recovery) exercise group. Serial muscle biopsies were obtained from vastus lateralis at rest before, immediately after, and after 15, 30, and 60 min of passive recovery to determine early signaling responses after exercise.
RESULTS: There were comparable increases from rest in Akt(Thr308/Ser473) and mTOR(Ser2448) phosphorylation during the postexercise time course that peaked 30-60 min after both CYC and REX (P < 0.05). There were also similar patterns in p70S6K(Thr389) and 4E-BP1(Thr37/46) phosphorylation, but a greater magnitude of effect was observed for REX and CYC, respectively (P < 0.05). However, AMPK(Thr172) phosphorylation was only significantly elevated after CYC (P < 0.05), and we observed divergent responses for glycogen synthase(Ser641) and AS160 phosphorylation that were enhanced after CYC but not REX (P < 0.05).
CONCLUSIONS: We show a similar time course for Akt-mTOR-S6K phosphorylation during the initial 60-min recovery period after divergent contractile stimuli. Conversely, enhanced phosphorylation status of proteins that promote glucose transport and glycogen synthesis only occurred after endurance exercise. Our results indicate that endurance and resistance exercise initiate translational signaling, but high-load, low-repetition contractile activity failed to promote phosphorylation of pathways regulating glucose metabolism.
Authors:
Donny M Camera; Johann Edge; Michael J Short; John A Hawley; Vernon G Coffey
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Publication Detail:
Type:  Journal Article; Randomized Controlled Trial; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Medicine and science in sports and exercise     Volume:  42     ISSN:  1530-0315     ISO Abbreviation:  Med Sci Sports Exerc     Publication Date:  2010 Oct 
Date Detail:
Created Date:  2010-09-27     Completed Date:  2011-01-13     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8005433     Medline TA:  Med Sci Sports Exerc     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1843-52     Citation Subset:  IM; S    
Affiliation:
School of Medical Science, Health Innovations Research Institute, RMIT University, Melbourne, Australia.
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MeSH Terms
Descriptor/Qualifier:
AMP-Activated Protein Kinases / analysis
Adaptor Proteins, Signal Transducing / analysis
Adult
Blood Glucose / metabolism,  physiology
GTPase-Activating Proteins / metabolism
Glycogen Synthase / analysis
Humans
Insulin / blood,  metabolism,  physiology
Lactic Acid / blood,  metabolism
Male
Muscle Contraction / physiology
Muscle, Skeletal / enzymology,  physiology
Phosphoproteins / analysis
Phosphorylation
Physical Endurance / physiology*
Proto-Oncogene Proteins c-akt / metabolism*
Resistance Training*
Ribosomal Protein S6 Kinases, 70-kDa / metabolism
TOR Serine-Threonine Kinases / analysis
Chemical
Reg. No./Substance:
0/Adaptor Proteins, Signal Transducing; 0/Blood Glucose; 0/EIF4EBP1 protein, human; 0/GTPase-Activating Proteins; 0/Phosphoproteins; 0/TBC1D4 protein, human; 11061-68-0/Insulin; 50-21-5/Lactic Acid; EC 2.4.1.11/Glycogen Synthase; EC 2.7.1.1/MTOR protein, human; EC 2.7.1.1/TOR Serine-Threonine Kinases; EC 2.7.11.1/AMP-Activated Protein Kinases; EC 2.7.11.1/Proto-Oncogene Proteins c-akt; EC 2.7.11.1/Ribosomal Protein S6 Kinases, 70-kDa

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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