Lee 2017 Am J Physiol Endocrinol Metab
| Lee S, Leone TC, Rogosa L, Rumsey J, Ayala J, Coen PM, Fitts RH, Vega RB, Kelly DP (2017) Skeletal muscle PGC-1Ξ² signaling is sufficient to drive an endurance exercise phenotype and to counteract components of detraining in mice. Am J Physiol Endocrinol Metab 312:E394-406. |
Lee S, Leone TC, Rogosa L, Rumsey J, Ayala J, Coen PM, Fitts RH, Vega RB, Kelly DP (2017) Am J Physiol Endocrinol Metab
Abstract: Peroxisome proliferator-activated receptor-Ξ³ coactivator (PGC)-1Ξ± and -1Ξ² 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-1Ξ² 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-1Ξ² overexpression in skeletal muscle of sedentary mice fully recapitulated the training response. Lastly, PGC-1Ξ² overexpression during the detraining period resulted in partial prevention of the detraining response. Specifically, an increase in the plateau at which O2 uptake (VΜO2) did not change from baseline with increasing treadmill speed [peak VΜO2 (ΞVΜVO2)] was maintained in trained mice with PGC-1Ξ² 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-1Ξ² overexpression. We conclude that while activation of muscle PGC-1Ξ² 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.
Copyright Β© 2017 the American Physiological Society. β’ Keywords: PGC-1, Endurance exercise, Muscle detraining, Skeletal muscle
Labels: MiParea: Respiration, nDNA;cell genetics, Exercise physiology;nutrition;life style
Organism: Mouse
Tissue;cell: Skeletal muscle
Preparation: Permeabilized tissue
Coupling state: LEAK, OXPHOS
Pathway: S
