Endurance exercise increases the SIRT1 and peroxisome proliferator-activated receptor gamma coactivator-1alpha protein expressions in rat skeletal muscle
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Endurance exercise increases the SIRT1 and peroxisome proliferator-
activated receptor gamma coactivator-1alpha protein expressions in rat
skeletal muscle.Suwa M, Nakano H, Radak Z, Kumagai S.
Institute of Health Science, Kyushu University, Kasuga, Fukuoka
816-8580, Japan.
Peroxisome proliferator-activated receptor gamma coactivator-1alpha
(PGC-1alpha) is considered to play a pivotal role in the exercise-
induced metabolic adaptation of skeletal muscle. Although the oxidized
form of nicotinamide adenine dinucloetide (NAD(+))-dependent histone
deacetylase SIRT1 has been shown to mediate PGC-1alpha-induced
metabolic adaptation, the effect of endurance exercise on the SIRT1
protein remains to be elucidated. The purposes of this study were (1)
to investigate the distribution of SIRT1 and PGC-1alpha proteins in
skeletal muscle and (2) to examine the effects of acute endurance
exercise and low- or high-intensity exercise training on SIRT1 and
PGC-1alpha protein expressions and on the metabolic components in rat
skeletal muscle. Both the SIRT1 and PGC-1alpha proteins preferentially
accumulate in red oxidative muscles. Acute endurance exercise on a
motor-driven treadmill (20 m/min, 18.5% incline, 45 minutes) increases
the PGC-1alpha protein expression at 18 hours after exercise and the
SIRT1 protein expression at 2 hours after exercise in the soleus
muscle. In the training experiment, the rats were divided into
control, low-intensity (20 m/min, 18.5% incline, 90 min/d), and high-
intensity (30 m/min, 18.5% incline, 60 min/d) training groups. After
14 days of training, the SIRT1 and PGC-1alpha proteins, hexokinase
activity, mitochondrial proteins and enzyme activities, and glucose
transporter 4 protein in the soleus muscle were increased by both
trainings. In the plantaris muscle, SIRT1, hexokinase activity,
mitochondrial proteins and enzyme activities, and glucose transporter
4 were increased by high-intensity training whereas the PGC-1alpha was
not. These results suggest that endurance exercise increases the
skeletal muscle SIRT1 protein content. In addition, the findings also
raise the possibility that the SIRT1 protein expression may play a
potentially important role in such adaptations, whereas an increase in
the PGC-1alpha protein expression is not necessary for such
adaptations.
PMID: 18555842