TY - JOUR
T1 - Moderate altitude but not additional endurance training increases markers of oxidative stress in exhaled breath condensate
AU - Heinicke, Ilmar
AU - Boehler, Annette
AU - Rechsteiner, Thomas
AU - Bogdanova, Anna
AU - Jelkmann, Wolfgang
AU - Hofer, Markus
AU - Rawlings, Pablo
AU - Araneda, Oscar F.
AU - Behn, Claus
AU - Gassmann, Max
AU - Heinicke, Katja
N1 - Funding Information:
Acknowledgments We thank the subjects from the Chilean army for their enthusiastic contribution and gratefully acknowledge technical support from Gisela Kuhn, Stephan Keller and Bianca Rohde-Saam. Johannes Vogel is acknowledged for fruitful discussions. This work has been supported by the Eidgenössische Sportkommission (ESK) des Bundesamtes für Sport (BASPO), by the Swiss National Science Foundation (3100A0-100214) and by the Fensterfabrik Albisrieden, Zurich, Switzerland (U. & G. Frei).
Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
PY - 2009
Y1 - 2009
N2 - Oxidative stress occurs at altitude, and physical exertion might enhance this stress. In the present study, we investigated the combined effects of exercise and moderate altitude on redox balance in ten endurance exercising biathletes, and five sedentary volunteers during a 6-week-stay at 2,800 m. As a marker for oxidative stress, hydrogen peroxide (H2O2) was analyzed by the biosensor measuring system Ecocheck™, and 8-iso prostaglandin F2α (8-iso PGF2α) was determined by enzyme immunoassay in exhaled breath condensate (EBC). To determine the whole blood antioxidative capacity, we measured reduced glutathione (GSH) enzymatically using Ellman's reagent. Exercising athletes and sedentary volunteers showed increased levels of oxidative markers at moderate altitude, contrary to our expectations; there was no difference between both groups. Therefore, all subjects' data were pooled to examine the oxidative stress response exclusively due to altitude exposure. H2 O2 levels increased at altitude and remained elevated for 3 days after returning to sea level (p ≤ 0.05). On the other hand, 8-iso PGF2α levels showed a tendency to increase at altitude, but declined immediately after returning to sea level (p ≤ 0.001). Hypoxic exposure during the first day at altitude resulted in elevated GSH levels (p ≤ 0.05), that decreased during prolonged sojourn at altitude (p ≤ 0.001). In conclusion, a stay at moderate altitude for up to 6 weeks increases markers of oxidative stress in EBC independent of additional endurance training. Notably, this oxidative stress is still detectable 3 days upon return to sea level.
AB - Oxidative stress occurs at altitude, and physical exertion might enhance this stress. In the present study, we investigated the combined effects of exercise and moderate altitude on redox balance in ten endurance exercising biathletes, and five sedentary volunteers during a 6-week-stay at 2,800 m. As a marker for oxidative stress, hydrogen peroxide (H2O2) was analyzed by the biosensor measuring system Ecocheck™, and 8-iso prostaglandin F2α (8-iso PGF2α) was determined by enzyme immunoassay in exhaled breath condensate (EBC). To determine the whole blood antioxidative capacity, we measured reduced glutathione (GSH) enzymatically using Ellman's reagent. Exercising athletes and sedentary volunteers showed increased levels of oxidative markers at moderate altitude, contrary to our expectations; there was no difference between both groups. Therefore, all subjects' data were pooled to examine the oxidative stress response exclusively due to altitude exposure. H2 O2 levels increased at altitude and remained elevated for 3 days after returning to sea level (p ≤ 0.05). On the other hand, 8-iso PGF2α levels showed a tendency to increase at altitude, but declined immediately after returning to sea level (p ≤ 0.001). Hypoxic exposure during the first day at altitude resulted in elevated GSH levels (p ≤ 0.05), that decreased during prolonged sojourn at altitude (p ≤ 0.001). In conclusion, a stay at moderate altitude for up to 6 weeks increases markers of oxidative stress in EBC independent of additional endurance training. Notably, this oxidative stress is still detectable 3 days upon return to sea level.
UR - http://www.scopus.com/inward/record.url?scp=67649361966&partnerID=8YFLogxK
U2 - 10.1007/s00421-009-1014-9
DO - 10.1007/s00421-009-1014-9
M3 - Journal articles
C2 - 19363619
AN - SCOPUS:67649361966
SN - 1439-6319
VL - 106
SP - 599
EP - 604
JO - European journal of applied physiology
JF - European journal of applied physiology
IS - 4
ER -