title: Home-based exercise training modulates pro-oxidant substrates in patients with chronic heart failure.
abstract: BACKGROUND
  In chronic heart failure, oxidative stress is thought to lead to endothelial dysfunction. In this study, we assessed the effect of home-based exercise training on variables of the NO and purine pathways.
  
  
  RESULTS
  Eighteen patients and nine controls were randomly assigned in cross-over design to 8 weeks of exercise training (5 days/week, submaximal bicycle ergometer training, 30 min/day; calisthenics 9 min/day) and 8 weeks of sedentary lifestyle. Hypoxanthine, xanthine, l-arginine, asymmetric dimethylarginine (ADMA), symmetric DMA (SDMA) and nitrite were measured. In patients, exercise training led to an increase in peak VO(2) (p<0.003). At baseline hypoxanthine-a pro-oxidant substrate and marker of hypoxia-was higher in patients than in controls (24.6+/-4.3 vs. 11.9+/-4.2 micromol/l; p<0.05). After training there was a reduction in hypoxanthine (p<0.01). Nitrite levels were lower in patients (416+/-31 micromol/l) than in healthy controls (583+/-35 micromol/l, p<0.001). Although nitrite levels were highest after exercise, the changes did not reach statistical significance (p=n.s.). l-Arginine, ADMA, and SDMA levels were not different between groups and were not altered by exercise training.
  
  
  CONCLUSIONS
  Chronic heart failure is associated with increased levels of hypoxanthine and decreased levels of nitrite. This imbalance can be beneficially modulated by chronic home-based exercise training.
authors.affiliation: Cardiac Medicine, Royal Brompton Hospital and NHLI, London, UK. j.niebauer@medizin.uni-leipzig.de
authors.forename: Josef
authors.initials: J
authors.lastname: Niebauer
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Clark
authors.forename: Katharine M
authors.initials: KM
authors.lastname: Webb-Peploe
authors.forename: Rainer
authors.initials: R
authors.lastname: Böger
authors.forename: Andrew J S
authors.initials: AJ
authors.lastname: Coats
mesh_terms: D000328:Adult; D001120:Arginine / Q000031:analogs & derivatives* / Q000097:blood; D018592:Cross-Over Studies; D015444:Exercise / Q000502:physiology*; D005260:Female; D006333:Heart Failure / Q000097:blood*; D006801:Humans; D019271:Hypoxanthine / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000097:blood; D009573:Nitrites / Q000097:blood; D019820:Xanthine / Q000097:blood*
chemical_list: D009566:Nitrates; D009573:Nitrites; D019820:Xanthine; D019271:Hypoxanthine; C018524:N,N-dimethylarginine; D001120:Arginine