Skeletal muscle-specific expression of PGC-1α-b, an exercise-responsive isoform, increases exercise capacity and peak oxygen uptake.
Maximal oxygen uptake (VO(2max)) predicts mortality and is associated with endurance performance. Trained subjects have a high VO(2max) due to a high cardiac output and high metabolic capacity of skeletal muscles. Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a nuclear recept...
Main Authors: | , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Public Library of Science (PLoS)
2011-01-01
|
Series: | PLoS ONE |
Online Access: | http://europepmc.org/articles/PMC3234261?pdf=render |
_version_ | 1819183165868081152 |
---|---|
author | Miki Tadaishi Shinji Miura Yuko Kai Yutaka Kano Yuichi Oishi Osamu Ezaki |
author_facet | Miki Tadaishi Shinji Miura Yuko Kai Yutaka Kano Yuichi Oishi Osamu Ezaki |
author_sort | Miki Tadaishi |
collection | DOAJ |
description | Maximal oxygen uptake (VO(2max)) predicts mortality and is associated with endurance performance. Trained subjects have a high VO(2max) due to a high cardiac output and high metabolic capacity of skeletal muscles. Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a nuclear receptor coactivator, promotes mitochondrial biogenesis, a fiber-type switch to oxidative fibers, and angiogenesis in skeletal muscle. Because exercise training increases PGC-1α in skeletal muscle, PGC-1α-mediated changes may contribute to the improvement of exercise capacity and VO(2max). There are three isoforms of PGC-1α mRNA. PGC-1α-b protein, whose amino terminus is different from PGC-1α-a protein, is a predominant PGC-1α isoform in response to exercise. We investigated whether alterations of skeletal muscle metabolism by overexpression of PGC-1α-b in skeletal muscle, but not heart, would increase VO(2max) and exercise capacity.Transgenic mice showed overexpression of PGC-1α-b protein in skeletal muscle but not in heart. Overexpression of PGC-1α-b promoted mitochondrial biogenesis 4-fold, increased the expression of fatty acid transporters, enhanced angiogenesis in skeletal muscle 1.4 to 2.7-fold, and promoted exercise capacity (expressed by maximum speed) by 35% and peak oxygen uptake by 20%. Across a broad range of either the absolute exercise intensity, or the same relative exercise intensities, lipid oxidation was always higher in the transgenic mice than wild-type littermates, suggesting that lipid is the predominant fuel source for exercise in the transgenic mice. However, muscle glycogen usage during exercise was absent in the transgenic mice.Increased mitochondrial biogenesis, capillaries, and fatty acid transporters in skeletal muscles may contribute to improved exercise capacity via an increase in fatty acid utilization. Increases in PGC-1α-b protein or function might be a useful strategy for sedentary subjects to perform exercise efficiently, which would lead to prevention of life-style related diseases and increased lifespan. |
first_indexed | 2024-12-22T22:57:42Z |
format | Article |
id | doaj.art-36213eea8a7948a9b5c7b845caf54ef5 |
institution | Directory Open Access Journal |
issn | 1932-6203 |
language | English |
last_indexed | 2024-12-22T22:57:42Z |
publishDate | 2011-01-01 |
publisher | Public Library of Science (PLoS) |
record_format | Article |
series | PLoS ONE |
spelling | doaj.art-36213eea8a7948a9b5c7b845caf54ef52022-12-21T18:09:46ZengPublic Library of Science (PLoS)PLoS ONE1932-62032011-01-01612e2829010.1371/journal.pone.0028290Skeletal muscle-specific expression of PGC-1α-b, an exercise-responsive isoform, increases exercise capacity and peak oxygen uptake.Miki TadaishiShinji MiuraYuko KaiYutaka KanoYuichi OishiOsamu EzakiMaximal oxygen uptake (VO(2max)) predicts mortality and is associated with endurance performance. Trained subjects have a high VO(2max) due to a high cardiac output and high metabolic capacity of skeletal muscles. Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a nuclear receptor coactivator, promotes mitochondrial biogenesis, a fiber-type switch to oxidative fibers, and angiogenesis in skeletal muscle. Because exercise training increases PGC-1α in skeletal muscle, PGC-1α-mediated changes may contribute to the improvement of exercise capacity and VO(2max). There are three isoforms of PGC-1α mRNA. PGC-1α-b protein, whose amino terminus is different from PGC-1α-a protein, is a predominant PGC-1α isoform in response to exercise. We investigated whether alterations of skeletal muscle metabolism by overexpression of PGC-1α-b in skeletal muscle, but not heart, would increase VO(2max) and exercise capacity.Transgenic mice showed overexpression of PGC-1α-b protein in skeletal muscle but not in heart. Overexpression of PGC-1α-b promoted mitochondrial biogenesis 4-fold, increased the expression of fatty acid transporters, enhanced angiogenesis in skeletal muscle 1.4 to 2.7-fold, and promoted exercise capacity (expressed by maximum speed) by 35% and peak oxygen uptake by 20%. Across a broad range of either the absolute exercise intensity, or the same relative exercise intensities, lipid oxidation was always higher in the transgenic mice than wild-type littermates, suggesting that lipid is the predominant fuel source for exercise in the transgenic mice. However, muscle glycogen usage during exercise was absent in the transgenic mice.Increased mitochondrial biogenesis, capillaries, and fatty acid transporters in skeletal muscles may contribute to improved exercise capacity via an increase in fatty acid utilization. Increases in PGC-1α-b protein or function might be a useful strategy for sedentary subjects to perform exercise efficiently, which would lead to prevention of life-style related diseases and increased lifespan.http://europepmc.org/articles/PMC3234261?pdf=render |
spellingShingle | Miki Tadaishi Shinji Miura Yuko Kai Yutaka Kano Yuichi Oishi Osamu Ezaki Skeletal muscle-specific expression of PGC-1α-b, an exercise-responsive isoform, increases exercise capacity and peak oxygen uptake. PLoS ONE |
title | Skeletal muscle-specific expression of PGC-1α-b, an exercise-responsive isoform, increases exercise capacity and peak oxygen uptake. |
title_full | Skeletal muscle-specific expression of PGC-1α-b, an exercise-responsive isoform, increases exercise capacity and peak oxygen uptake. |
title_fullStr | Skeletal muscle-specific expression of PGC-1α-b, an exercise-responsive isoform, increases exercise capacity and peak oxygen uptake. |
title_full_unstemmed | Skeletal muscle-specific expression of PGC-1α-b, an exercise-responsive isoform, increases exercise capacity and peak oxygen uptake. |
title_short | Skeletal muscle-specific expression of PGC-1α-b, an exercise-responsive isoform, increases exercise capacity and peak oxygen uptake. |
title_sort | skeletal muscle specific expression of pgc 1α b an exercise responsive isoform increases exercise capacity and peak oxygen uptake |
url | http://europepmc.org/articles/PMC3234261?pdf=render |
work_keys_str_mv | AT mikitadaishi skeletalmusclespecificexpressionofpgc1abanexerciseresponsiveisoformincreasesexercisecapacityandpeakoxygenuptake AT shinjimiura skeletalmusclespecificexpressionofpgc1abanexerciseresponsiveisoformincreasesexercisecapacityandpeakoxygenuptake AT yukokai skeletalmusclespecificexpressionofpgc1abanexerciseresponsiveisoformincreasesexercisecapacityandpeakoxygenuptake AT yutakakano skeletalmusclespecificexpressionofpgc1abanexerciseresponsiveisoformincreasesexercisecapacityandpeakoxygenuptake AT yuichioishi skeletalmusclespecificexpressionofpgc1abanexerciseresponsiveisoformincreasesexercisecapacityandpeakoxygenuptake AT osamuezaki skeletalmusclespecificexpressionofpgc1abanexerciseresponsiveisoformincreasesexercisecapacityandpeakoxygenuptake |