TY - JOUR
T1 - Moderate caloric restriction increases diaphragmatic antioxidant enzyme mRNA, but not when combined with lifelong exercise
AU - Deruisseau, Keith C.
AU - Kavazis, Andreas N.
AU - Judge, Sharon
AU - Murlasits, Zsolt
AU - Deering, Melissa A.
AU - Quindry, John C.
AU - Lee, Youngil
AU - Falk, Darin J.
AU - Leeuwenburgh, Christiaan
AU - Powers, Scott K.
PY - 2006/3
Y1 - 2006/3
N2 - Diaphragmatic antioxidant enzymes are upregulated following acute and long-term treadmill exercise, but the effect of lifelong voluntary exercise (E) on diaphragmatic antioxidants is unknown. Therefore, 10-week old Fisher 344 rats were assigned to either: (a) sedentary ad libitum (AL) fed (24AL; n = 6); (b) E + 8% caloric restriction (24ECR; n = 9); or (c) sedentary + 8% caloric restriction (24CR; n = 9) groups. Diaphragms were harvested from animals at 24 months of age. Heme oxygenase-1 (HO-1) mRNA in addition to catalase (CAT), glutathione peroxidase (GPX), copper-zinc superoxide dismutase (Cu-ZnSOD) and manganese superoxide dismutase (MnSOD) mRNA and protein levels were measured. Reduced glutathione (GSH) and citrate synthase (CS) activity were measured to assess antioxidant status and oxidative capacity, respectively. The 24CR group demonstrated increased GPX, HO-1, MnSOD, and CAT mRNA compared to 24AL and 24ECR. Interestingly, the increased mRNA in 24CR animals did not result in elevated protein levels. No group differences in Cu-ZnSOD mRNA, CS activity, or GSH were observed, although GSH was 30% greater in 24CR animals (p = 0.085). In summary, although CR elevated the mRNA of key antioxidant enzymes in the diaphragm, life-long CR alone or in combination with voluntary exercise did not alter diaphragm CS activity, antioxidant protein quantity, or GSH levels.
AB - Diaphragmatic antioxidant enzymes are upregulated following acute and long-term treadmill exercise, but the effect of lifelong voluntary exercise (E) on diaphragmatic antioxidants is unknown. Therefore, 10-week old Fisher 344 rats were assigned to either: (a) sedentary ad libitum (AL) fed (24AL; n = 6); (b) E + 8% caloric restriction (24ECR; n = 9); or (c) sedentary + 8% caloric restriction (24CR; n = 9) groups. Diaphragms were harvested from animals at 24 months of age. Heme oxygenase-1 (HO-1) mRNA in addition to catalase (CAT), glutathione peroxidase (GPX), copper-zinc superoxide dismutase (Cu-ZnSOD) and manganese superoxide dismutase (MnSOD) mRNA and protein levels were measured. Reduced glutathione (GSH) and citrate synthase (CS) activity were measured to assess antioxidant status and oxidative capacity, respectively. The 24CR group demonstrated increased GPX, HO-1, MnSOD, and CAT mRNA compared to 24AL and 24ECR. Interestingly, the increased mRNA in 24CR animals did not result in elevated protein levels. No group differences in Cu-ZnSOD mRNA, CS activity, or GSH were observed, although GSH was 30% greater in 24CR animals (p = 0.085). In summary, although CR elevated the mRNA of key antioxidant enzymes in the diaphragm, life-long CR alone or in combination with voluntary exercise did not alter diaphragm CS activity, antioxidant protein quantity, or GSH levels.
UR - http://www.scopus.com/inward/record.url?scp=33646711670&partnerID=8YFLogxK
U2 - 10.1089/ars.2006.8.539
DO - 10.1089/ars.2006.8.539
M3 - Article
C2 - 16677098
AN - SCOPUS:33646711670
SN - 1523-0864
VL - 8
SP - 539
EP - 547
JO - Antioxidants and Redox Signaling
JF - Antioxidants and Redox Signaling
IS - 3-4
ER -