TY - JOUR
T1 - Electron paramagnetic spectroscopic evidence of exercise-induced free radical accumulation in human skeletal muscle
AU - Bailey, Damian A.
AU - Lawrenson, Leslie
AU - McEneny, Jane
AU - Young, Ian S.
AU - James, Philip E.
AU - Jackson, Simon K.
AU - Henry, Robert R.
AU - Mathieu-Costello, Odile
AU - McCord, Joe M.
AU - Richardson, Russell S.
PY - 2007
Y1 - 2007
N2 - The present study determined if acute exercise increased free radical formation in human skeletal muscle. Vastus lateralis biopsies were obtained in a randomized balanced order from six males at rest and following single-leg knee extensor exercise performed for 2 min at 50% of maximal work rate (WRMAX) and 3 min at 100% WRMAX. EPR spectroscopy revealed an exercise-induced increase in mitochondrial ubisemiquinone (UQ- [0.167 ± 0.055 vs. rest: 0.106 ± 0.047 arbitrary units (AU)/g total protein (TP), P < 0.05] and α-phenyl-tert-butylnitrone-adducts (112 ± 41 vs. rest: 29 ± AU/mg tissue mass, P < 0.05). Intramuscular lipid hydroperoxides also increased (0.320 ± 0.263 vs. rest: 0.148 ± 0.071 nmol/mg TP, P < 0.05) despite an uptake of α-tocopherol, α-carotene and β-carotene. There were no relationships between mitochondrial volume density and any biomarkers of oxidative stress. These findings provide the first direct evidence for intramuscular free radical accumulation and lipid peroxidation following acute exercise in humans.
AB - The present study determined if acute exercise increased free radical formation in human skeletal muscle. Vastus lateralis biopsies were obtained in a randomized balanced order from six males at rest and following single-leg knee extensor exercise performed for 2 min at 50% of maximal work rate (WRMAX) and 3 min at 100% WRMAX. EPR spectroscopy revealed an exercise-induced increase in mitochondrial ubisemiquinone (UQ- [0.167 ± 0.055 vs. rest: 0.106 ± 0.047 arbitrary units (AU)/g total protein (TP), P < 0.05] and α-phenyl-tert-butylnitrone-adducts (112 ± 41 vs. rest: 29 ± AU/mg tissue mass, P < 0.05). Intramuscular lipid hydroperoxides also increased (0.320 ± 0.263 vs. rest: 0.148 ± 0.071 nmol/mg TP, P < 0.05) despite an uptake of α-tocopherol, α-carotene and β-carotene. There were no relationships between mitochondrial volume density and any biomarkers of oxidative stress. These findings provide the first direct evidence for intramuscular free radical accumulation and lipid peroxidation following acute exercise in humans.
UR - http://www.scopus.com/inward/record.url?scp=34250893768&partnerID=8YFLogxK
U2 - 10.1080/10715760601028867
DO - 10.1080/10715760601028867
M3 - Article
C2 - 17364944
AN - SCOPUS:34250893768
SN - 1071-5762
VL - 41
SP - 182
EP - 190
JO - Free Radical Research
JF - Free Radical Research
IS - 2
ER -