Differential transcriptional activation of select metabolic genes in response to variations in exercise intensity and duration

• Published in: American journal of physiology: endocrinology and metabolism 2003-11, Vol.285 (5), p.E1021-E1027
• Main Authors: Hildebrandt, Audrey L, Pilegaard, Henriette, Neufer, P. Darrell
• Format: Article
• Language: English
• Subjects: Animals; Carrier Proteins - genetics; Gene Expression Regulation; Heme Oxygenase (Decyclizing) - genetics; Heme Oxygenase-1; Hexokinase - genetics; Ion Channels; Isoenzymes - genetics; Lipoprotein Lipase - genetics; Male; Mitochondrial Proteins; Muscle Fibers, Fast-Twitch - metabolism; Muscle, Skeletal - metabolism; Oxygen Consumption; Physical Endurance - genetics; Physical Exertion; Polymerase Chain Reaction; Protein Kinases - genetics; Rats; Rats, Sprague-Dawley; Transcription, Genetic - genetics; Transcriptional Activation; Uncoupling Protein 3
• ISSN: 0193-1849; 1522-1555
• DOI: 10.1152/ajpendo.00234.2003

1 John B. Pierce Laboratory and 2 Department of Cellular and Molecular Physiology, Yale University, New Haven, Connecticut 06519; and 3 Copenhagen Muscle Research Center and August Krogh Institute, University of Copenhagen, Copenhagen, Denmark Submitted 21 May 2003 ; accepted in final form 28 July 2003 Cellular adaptations to endurance training are influenced by the intensity and duration of exercise. To examine the impact of exercise intensity and duration on the acute transcriptional regulation of metabolic genes in red (RG) and white (WG) gastrocnemius muscle, rats completed either low-intensity [ 50% maximal O 2 uptake ( O 2 max )] treadmill exercise (LIE) for 45 min, LIE for 180 min, or high-intensity ( 75% O 2 max ) exercise (HIE) for 45 min. LIE for 45 min activated ( P < 0.05) transcription of the pyruvate dehydrogenase kinase-4 (PDK4), uncoupling protein-3 (UCP3), heme oxygenase-1 (HO-1), and hexokinase II (HK II) genes in RG within 1 h after exercise. In WG, transcription of PDK4, UCP3, HKII, and lipoprotein lipase (LPL) was also induced, whereas transcription of the HO-1 gene did not change. In RG, extending LIE duration from 45 to 180 min elicited a similar activation of PDK4 and UCP3 ( 15-fold) but a far greater increase in HO-1 (>30-fold) and HKII transcription (>25-fold). In WG, extending LIE for 180 min induced a much greater and prolonged (through 2- to 4-h recovery) activation of PDK4, UCP3 (both >200-fold), and HO-1 (>10-fold). HIE elicited a similar pattern of gene activation to LIE in both RG and WG, with the exception that HIE triggered >10-fold activation of HO-1 in WG. These data provide evidence that both the intensity and the duration of exercise affect the transcriptional regulation of metabolic genes in muscle in a fiber type-specific manner, possibly reflecting the relative stress imposed by the exercise bout. endurance training; mitochondrial biogenesis; gene regulation Address for reprint requests and other correspondence: P. D. Neufer, John B. Pierce Laboratory, 290 Congress Ave., New Haven, CT 06519 (E-mail: dneufer{at}jbpierce.org ).