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Exerc Sci > Volume 13(2); 2004 > Article

Exercise Science 2004;13(2): 177-188.

쥐 골격근의 산화효소 활성, PPAR 단백질 및 지질대사 관련 mRNA 발현에 미치는 트레이닝 효과

이장규¹, 조인호², 김창근², 박인숙³, 이종삼², 박수연²

²한국체육대학교
³상명대학교

ABSTRACT

Effects of long term regular exercise on oxidative enzyme activities, and peroxisome proliferators activated receptor protein and mRNA expressions that are involved in lipid oxidative process in rat soleus muscles. Exercise Science, 13(2): 177-188, 2004. We investigated whether long term regular training exerts any significant roles in regulatory genes (i.e., fatty acid trans- locase [FAT/CD36] mRNA, carnitine palmitoyl transferase [CPT-I] mRNA, β-hydroxyacyl CoA dehydrogenase [β-HAD] ｍＲＮＡ, pyruvate dehydrogenase kinase-4 [PDK4]　ｍＲＮＡ, mitochondrial uncoupling protein-3 [UCP3]　ｍＲＮＡ) and proteins (peroxisome proliferators activated receptor [PPAR]α and γ) expression, and enzyme (citrate synthase [CS] and [β-HAD]) activities that closely involved in lipid uptake and oxidation in skeletal muscle cells. Sixteen female Sprague- Dawley rats were used, and divided into two experimental conditions: either untrained (n=8) or trained (n=8). While rats in untrained group performed no training, animals in trained group undertook 8wk of regular exercise (4 timeswk-1, 1000msession-1) on the treadmill. Although training tended to upregulate the expression of all genes important for lipid oxidation, β-HAD mRNA significantly decreased (p<0.05). Unlike our hypothesis, there was no exercise training effect on PPAR α and γ protein abundance (p>0.05). Similar to PPAR protein expressions, oxidative enzymes did not also show any significant alteration following 8wk regular training program. It was suggested that regular aerobic exercise does not affect on PPAR α and γ as well as gene expressions in oxidative skeletal muscle fibers. Studies examining of this molecular response including the major transcriptional regulators, and gene expressions following various training regimens (i.e., training duration and intensities) are required.

Key words: exercise training, gene expressions, protein abundance, enzyme activity, oxidative metabolism