TY - JOUR
T1 - Impact of endurance training on murine spontaneous activity, muscle mitochondrial DNA abundance, gene transcripts, and function
AU - Chow, Lisa S.
AU - Greenlund, Laura J.
AU - Asmann, Yan W.
AU - Short, Kevin R.
AU - McCrady, Shelly K.
AU - Levine, James A.
AU - Nair, K. Sreekumaran
PY - 2007/3
Y1 - 2007/3
N2 - We hypothesized that enhanced skeletal muscle mitochondrial function following aerobic exercise training is related to an increase in mitochondrial transcription factors, DNA abundance [mitochondrial DNA (mtDNA)], and mitochondria-related gene transcript levels, as well as spontaneous physical activity (SPA) levels. We report the effects of daily treadmill training on 12-wk-old FVB mice for 5 days/wk over 8 wk at 80% peak O2 consumption and studied the training effect on changes in body composition, glucose tolerance, muscle mtDNA muscle, mitochondria-related gene transcripts, in vitro muscle mitochondrial ATP production capacity (MATPC), and SPA levels. Compared with the untrained mice, the trained mice had higher peak O2 consumption (+18%; P < 0.001), lower percentage of abdominal (-25.4%; P < 0.02) and body fat (-19.5%; P < 0.01), improved glucose tolerance (P < 0.04), and higher muscle mitochondrial enzyme activity (+19.5- 43.8%; P < 0.04) and MATPC (+28.9 to +32.4%; P < 0.01). Gene array analysis showed significant differences in mRNAs of mitochondria-related ontology groups between the trained and untrained mice. Training also increased muscle mtDNA (+88.4 to +110%; P < 0.05), peroxisome proliferative-activated receptor-γ coactivator-1α protein (+99.5%; P < 0.04), and mitochondrial transcription factor A mRNA levels (+21.7%; P < 0.004) levels. SPA levels were higher in trained mice (P =- 0.056, two-sided t-test) and significantly correlated with two separate substrate-based measurements of MATPC (P < 0.02). In conclusion, aerobic exercise training enhances muscle mitochondrial transcription factors, mtDNA abundance, mitochondria-related gene transcript levels, and mitochondrial function, and this enhancement in mitochondrial function occurs in association with increased SPA.
AB - We hypothesized that enhanced skeletal muscle mitochondrial function following aerobic exercise training is related to an increase in mitochondrial transcription factors, DNA abundance [mitochondrial DNA (mtDNA)], and mitochondria-related gene transcript levels, as well as spontaneous physical activity (SPA) levels. We report the effects of daily treadmill training on 12-wk-old FVB mice for 5 days/wk over 8 wk at 80% peak O2 consumption and studied the training effect on changes in body composition, glucose tolerance, muscle mtDNA muscle, mitochondria-related gene transcripts, in vitro muscle mitochondrial ATP production capacity (MATPC), and SPA levels. Compared with the untrained mice, the trained mice had higher peak O2 consumption (+18%; P < 0.001), lower percentage of abdominal (-25.4%; P < 0.02) and body fat (-19.5%; P < 0.01), improved glucose tolerance (P < 0.04), and higher muscle mitochondrial enzyme activity (+19.5- 43.8%; P < 0.04) and MATPC (+28.9 to +32.4%; P < 0.01). Gene array analysis showed significant differences in mRNAs of mitochondria-related ontology groups between the trained and untrained mice. Training also increased muscle mtDNA (+88.4 to +110%; P < 0.05), peroxisome proliferative-activated receptor-γ coactivator-1α protein (+99.5%; P < 0.04), and mitochondrial transcription factor A mRNA levels (+21.7%; P < 0.004) levels. SPA levels were higher in trained mice (P =- 0.056, two-sided t-test) and significantly correlated with two separate substrate-based measurements of MATPC (P < 0.02). In conclusion, aerobic exercise training enhances muscle mitochondrial transcription factors, mtDNA abundance, mitochondria-related gene transcript levels, and mitochondrial function, and this enhancement in mitochondrial function occurs in association with increased SPA.
KW - Endurance exercise
KW - Gene array
KW - Mitochondria adenosine 5′-triphosphate production
KW - Mouse
KW - Physical activity
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U2 - 10.1152/japplphysiol.00791.2006
DO - 10.1152/japplphysiol.00791.2006
M3 - Article
C2 - 17110513
AN - SCOPUS:33847766208
SN - 8750-7587
VL - 102
SP - 1078
EP - 1089
JO - Journal of applied physiology
JF - Journal of applied physiology
IS - 3
ER -