Effects of low-intensity prolonged exercise on PGC-1 mRNA expression in rat epitrochlearis muscle

Biochem Biophys Res Commun. 2002 Aug 16;296(2):350-4. doi: 10.1016/s0006-291x(02)00881-1.

Abstract

We previously reported that the peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) mRNA in rat epitrochlearis muscle was increased after swimming exercise training. In the present study, we demonstrated further that PGC-1 mRNA expression in the epitrochlearis muscle of 4-5-week-old male Sprague-Dawley rats was increased after a 6-h acute bout of low-intensity swimming exercise. With this increase, the expression level was approximately 8-fold of control and immersion group rats that stayed for 6-h in warm water, maintained at the identical temperature of the swimming barrel (35 degrees C) (p<0.01). Second, PGC-1 mRNA expression in the muscle was found to have increased 6-h after 30 10-s tetani contractions were induced by in vitro electrical stimulation. Finally, PGC-1 mRNA expression in the muscle incubated for 18-h with 0.5mM 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR: a 5' AMP-activated protein kinase (AMPK) activator) was elevated to approximately 3-fold of the control muscle (n=6, p<0.001). AMPK activity in epitrochlearis muscle after the swimming was also found to be elevated to approximately 4-fold of the pre-exercise value (p<0.001). These results may suggest that an acute bout of low-intensity prolonged swimming exercise directly enhances the PGC-1 mRNA expression in the activated muscle during exercise, possibly through, at least in part, an AMPK-related mechanism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AMP-Activated Protein Kinases
  • Aminoimidazole Carboxamide / analogs & derivatives*
  • Aminoimidazole Carboxamide / pharmacology
  • Animals
  • Electric Stimulation
  • Enzyme Activation
  • In Vitro Techniques
  • Male
  • Multienzyme Complexes / metabolism
  • Muscle Contraction / physiology
  • Muscle, Skeletal / drug effects
  • Muscle, Skeletal / metabolism*
  • Physical Conditioning, Animal*
  • Protein-Serine-Threonine Kinases / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Ribonucleosides / pharmacology
  • Swimming
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*

Substances

  • Multienzyme Complexes
  • Ribonucleosides
  • Transcription Factors
  • peroxisome-proliferator-activated receptor-gamma coactivator-1
  • Aminoimidazole Carboxamide
  • acadesine
  • Protein-Serine-Threonine Kinases
  • AMP-Activated Protein Kinases