Acute exercise induces biphasic increase in respiratory mRNA in skeletal muscle.
Peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) promotes the expression of oxidative enzymes in skeletal muscle. We hypothesized that activation of the p38 MAPK (mitogen-activated protein kinase) in response to exercise was associated with exercise-induced PGC-1alpha and respiratory enzymes expression and aimed to demonstrate this under the physiological level. We subjected mice to a single bout of treadmill running and found that the exercise induced a biphasic increase in the expression of respiratory enzymes mRNA. The second phase of the increase was accompanied by an increase in PGC-1alpha protein, but the other was not. Administration of SB203580 (SB), an inhibitor of p38 MAPK, suppressed the increase in PGC-1alpha expression and respiratory enzymes mRNA in both phases. These data suggest that p38 MAPK is associated with the exercise-induced expression of PGC-1alpha and biphasic increase in respiratory enzyme mRNAs in mouse skeletal muscle under physiological conditions.
Ikeda
Shin-ichi
S
Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8574, Japan.
Kizaki
Takako
T
Haga
Shukoh
S
Ohno
Hideki
H
Takemasa
Tohru
T
D000818:Animals; D019069:Cell Respiration / Q000502:physiology; D005080:Exercise Test; D005260:Female; D051379:Mice; D008813:Mice, Inbred ICR; D008928:Mitochondria / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000502:physiology*; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D010805:Physical Conditioning, Animal / Q000379:methods*; D010807:Physical Endurance / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism*; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; C485290:Ppargc1a protein, mouse; D012333:RNA, Messenger; D015534:Trans-Activators; D014157:Transcription Factors; D048051:p38 Mitogen-Activated Protein Kinases