Antioxidative effects of exercise training in patients with chronic heart failure: increase in radical scavenger enzyme activity in skeletal muscle.
BACKGROUND
In chronic heart failure (CHF), cross-talk between inflammatory activation and oxidative stress has been anticipated in skeletal muscle (SM). The role of the radical scavenger enzymes superoxide dismutase (SOD), catalase (Cat), and glutathione peroxidase (GPX), which remove oxygen radicals, has never been assessed in the SM in this context. Moreover, it remains unknown whether exercise training augments the activity of these enzymes in CHF.


RESULTS
Twenty-three patients with CHF were randomized to either 6 months of exercise training (T) or a sedentary lifestyle (C); 12 age-matched healthy subjects (HS) were studied in parallel. Activity of Cat, SOD, and GPX was assessed in SM biopsies before and after 6 months (6 months). Oxidative stress was determined by measuring nitrotyrosine formation. SOD, Cat, and GPX activity was reduced by 31%, 57%, and 51%, respectively, whereas nitrotyrosine formation was increased by 107% in SM in CHF (P<0.05 versus HS). In CHF, exercise training augmented GPX and Cat activity in SM by 41% (P<0.05 versus before and group C) and 42% (P<0.05 versus before and group C), respectively, and decreased nitrotyrosine production by 35% (from 3.8+/-0.4% tissue area before to 2.5+/-0.3% after 6 months; P<0.05 versus before).


CONCLUSIONS
The reduced activity of major antioxidative enzymes in the SM of CHF patients is associated with increased local oxidative stress. Exercise training exerts antioxidative effects in the SM in CHF, in particular, due to an augmentation in activity of radical scavenger enzymes.
Linke
Axel
A
Heart Center, Department of Cardiology, University of Leipzig, Leipzig, Germany. linkea@medizin.uni-leipzig.de
Adams
Volker
V
Schulze
Paul Christian
PC
Erbs
Sandra
S
Gielen
Stephan
S
Fiehn
Eduard
E
Möbius-Winkler
Sven
S
Schubert
Andreas
A
Schuler
Gerhard
G
Hambrecht
Rainer
R
D016022:Case-Control Studies; D002374:Catalase / Q000032:analysis / Q000235:genetics; D002908:Chronic Disease; D005081:Exercise Therapy; D016166:Free Radical Scavengers / Q000032:analysis; D005979:Glutathione Peroxidase / Q000032:analysis / Q000235:genetics; D006333:Heart Failure / Q000201:enzymology / Q000378:metabolism / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism; D018384:Oxidative Stress; D011659:Pulmonary Gas Exchange; D012333:RNA, Messenger / Q000032:analysis; D013482:Superoxide Dismutase / Q000032:analysis / Q000235:genetics
D016166:Free Radical Scavengers; D012333:RNA, Messenger; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase