Does antioxidant system adaptive response alleviate related oxidative damage with long term bed rest?
OBJECTIVE
The aim of the study was to evidence oxidative damage and erythrocyte antioxidant enzyme activities during long term bed rest (LTBR) and recovery, while verifying the prophylactic effects of resistance exercise on LTBR-induced oxidative damage.


METHODS
11 healthy male participated in the study. Nutrient intakes were monitored. Assessments occurred during LTBR (60th and 90th day) and 90 days after the end.


RESULTS
LTBR induced only a slight decrease in total thiol protein (SH) group concentrations. Glutathione peroxidase (GPx) activity was upregulated during LTBR and down regulated after recovery suggesting that hypokinesia induces an oxidative stress. These effects where not correlated to antioxidant intake as nutritional density is preserved. Lipoperoxidative markers stay unchanged.


CONCLUSIONS
Exercise alleviates hypokinesia outcomes by preserving glutathione reductase activity with minor effect on hypokinesia-induced antioxidant response and oxidative stress which both exhibit a high magnitude inter-individual variability. Return to initial physical activity allows biomarkers to return to initial values marking the end of the stress. Hypokinetic situations should be considered as an oxidative stressful situation requiring exercise and nutritional strategies.
Margaritis
I
I
Department for evaluation of nutritional and health risks, French Food Safety Agency, Maisons-Alfort, France. i.margaritis@afssa.fr
Rousseau
A S
AS
Marini
J F
JF
Chopard
A
A
D000222:Adaptation, Physiological; D000328:Adult; D000975:Antioxidants / Q000378:metabolism*; D001510:Bed Rest; D015415:Biomarkers / Q000097:blood; D002338:Carotenoids / Q000378:metabolism; D004032:Diet; D004912:Erythrocytes / Q000201:enzymology; D015444:Exercise / Q000502:physiology; D005247:Feeding Behavior; D005980:Glutathione Reductase / Q000378:metabolism; D006439:Hemodynamics; D006728:Hormones / Q000097:blood; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology; D018384:Oxidative Stress; D011187:Posture / Q000502:physiology; D013482:Superoxide Dismutase / Q000378:metabolism; D013997:Time Factors; D014131:Trace Elements / Q000378:metabolism
D000975:Antioxidants; D015415:Biomarkers; D006728:Hormones; D014131:Trace Elements; D002338:Carotenoids; D013482:Superoxide Dismutase; D005980:Glutathione Reductase