Skeletal muscle PGC-1β signaling is sufficient to drive an endurance exercise phenotype and to counteract components of detraining in mice. Am J Physiol Endocrinol Metab 2017 May 01;312(5):E394-E406
Date
03/09/2017Pubmed ID
28270443Pubmed Central ID
PMC5451529DOI
10.1152/ajpendo.00380.2016Scopus ID
2-s2.0-85018422366 (requires institutional sign-in at Scopus site) 15 CitationsAbstract
Peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α and -1β serve as master transcriptional regulators of muscle mitochondrial functional capacity and are capable of enhancing muscle endurance when overexpressed in mice. We sought to determine whether muscle-specific transgenic overexpression of PGC-1β affects the detraining response following endurance training. First, we established and validated a mouse exercise-training-detraining protocol. Second, using multiple physiological and gene expression end points, we found that PGC-1β overexpression in skeletal muscle of sedentary mice fully recapitulated the training response. Lastly, PGC-1β overexpression during the detraining period resulted in partial prevention of the detraining response. Specifically, an increase in the plateau at which O2 uptake (V̇o2) did not change from baseline with increasing treadmill speed [peak V̇o2 (ΔV̇o2max)] was maintained in trained mice with PGC-1β overexpression in muscle 6 wk after cessation of training. However, other detraining responses, including changes in running performance and in situ half relaxation time (a measure of contractility), were not affected by PGC-1β overexpression. We conclude that while activation of muscle PGC-1β is sufficient to drive the complete endurance phenotype in sedentary mice, it only partially prevents the detraining response following exercise training, suggesting that the process of endurance detraining involves mechanisms beyond the reversal of muscle autonomous mechanisms involved in endurance fitness. In addition, the protocol described here should be useful for assessing early-stage proof-of-concept interventions in preclinical models of muscle disuse atrophy.
Author List
Lee S, Leone TC, Rogosa L, Rumsey J, Ayala J, Coen PM, Fitts RH, Vega RB, Kelly DPAuthor
Robert Fitts PhD Professor in the Biological Sciences department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
AnimalsMale
Mice
Mice, Transgenic
Muscle, Skeletal
Muscular Disorders, Atrophic
Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
Phenotype
Physical Conditioning, Animal
Physical Endurance
Physical Fitness
Running
