Endurance training limits the functional alterations of rat heart mitochondria submitted to in vitro anoxia-reoxygenation

Int J Cardiol. 2006 May 10;109(2):169-78. doi: 10.1016/j.ijcard.2005.06.003. Epub 2005 Jul 14.


Background: Studies analysing the effect of endurance training on heart mitochondrial function submitted to in vitro anoxia-reoxygenation (A-R) are missing. The present study aimed to investigate the effect of moderate endurance treadmill training (14 weeks) against rat heart mitochondrial dysfunction induced by in vitro A-R.

Methods: Respiratory parameters (state 3, state 4, ADP/O and respiratory control ratio-RCR) and oxidative damage markers (carbonyl groups and malondialdehyde) were determined in isolated mitochondria before and after 1 min anoxia followed by 4 min reoxygenation. Levels of heat shock protein 60 kDa (HSP60) and 70 kDa (HSP70) were measured before A-R in mitochondria and whole muscle homogenate, respectively.

Results: A-R significantly impaired the rate of state 3 and state 4 respiration, as well as the RCR and ADP/O in the sedentary group. However, mitochondrial state 3 respiration was significantly higher in trained than in the sedentary group both before and after A-R. The impairments in RCR, ADP/O ratio and state 4 induced by A-R in sedentary group were significantly attenuated in endurance-trained group. The inhibition of state 4 induced by GDP was significantly higher in trained than in sedentary group. Oxidative modifications of mitochondrial proteins and phospholipids were found in sedentary group after A-R, although limited in trained group. Increased levels of mitochondrial HSP60 and tissue HSP70 accompanied the lower decrease in the respiratory function after A-R observed in trained group.

Conclusion: We therefore concluded that endurance training limited the impairments on rat heart mitochondria caused by the oxidant insult inflicted by in vitro A-R.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Biomarkers / metabolism
  • Cell Respiration
  • Chaperonin 60 / metabolism
  • Citrate (si)-Synthase / metabolism
  • Disease Models, Animal
  • Exercise Test
  • HSP70 Heat-Shock Proteins / metabolism
  • Hypoxia / metabolism
  • Hypoxia / physiopathology*
  • Lipid Peroxidation
  • Male
  • Mitochondria, Heart / metabolism*
  • Oxidative Phosphorylation
  • Oxygen Consumption*
  • Physical Conditioning, Animal*
  • Physical Endurance*
  • Protein Carbonylation
  • Rats
  • Rats, Wistar


  • Biomarkers
  • Chaperonin 60
  • HSP70 Heat-Shock Proteins
  • Citrate (si)-Synthase