Effect of resistance exercise intensity on the expression of PGC-1α isoforms and the anabolic and catabolic signaling mediators, IGF-1 and myostatin, in human skeletal muscle.
The purpose of this study was to investigate the acute messenger (mRNA) expression of the peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) isoforms, insulin-like growth factor-1Ea (IGF-1Ea), and myostatin in response to 2 resistance exercise intensities. In a uniform-balanced, crossover design, 10 participants performed 2 separate testing sessions involving a lower body resistance exercise component consisting of a lower intensity (50% of 1-repetition maximum; 1RM) protocol and a higher intensity (80% of 1RM) protocol of equal volumes. Muscle samples were obtained at before exercise, 45 min, 3 h, 24 h, and 48 h postexercise. Resistance exercise did not alter total PGC-1α mRNA expression; however, distinct responses of each PGC-1α isoform were observed. The response of each isoform was consistent between sessions, suggesting no effect of resistance exercise intensity on the complex transcriptional expression of the PGC-1α gene. IGF-1Ea mRNA expression significantly increased following the higher intensity session compared with pre-exercise and the lower intensity session. Myostatin mRNA expression was significantly reduced compared with pre-exercise values at all time points with no difference between exercise intensity. Further research is needed to determine the effects of the various isoforms of PGC-1α in human skeletal muscle on the translational level as well as their relation to the expression of IGF-1 and myostatin.
['Schwarz|Neil A|NA|', 'McKinley-Barnard|Sarah K|SK|', 'Spillane|Mike B|MB|', 'Andre|Thomas L|TL|', 'Gann|Joshua J|JJ|', 'Willoughby|Darryn S|DS|']
D000293:Adolescent D000328:Adult D015992:Body Mass Index D018592:Cross-Over Studies D005786:Gene Expression Regulation D006801:Humans D007334:Insulin-Like Growth Factor I D008297:Male D018482:Muscle, Skeletal D055435:Myostatin D047495:PPAR gamma D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha D010807:Physical Endurance D011401:Promoter Regions, Genetic D012333:RNA, Messenger D055070:Resistance Training D015398:Signal Transduction D055815:Young Adult
resistance exercise exercise intensity PGC-1α IGF-1 myostatin myostatin skeletal muscle exercice contre résistance expression génique gene expression intensité de l’exercice muscle squelettique myostatine