Protecting effect of vitamin E supplementation on submaximal exercise-induced oxidative stress in sedentary dogs as assessed by erythrocyte membrane fluidity and paraoxonase-1 activity

The aim of this placebo-con trolled Study was to investigate the effects of oral vitamin E Supplementation for 10 weeks on exercise-induced oxidative damage in untrained dogs. Eight clogs were randomly assigned to it supplementation (n = 4) or control (n = 4) group and underwent two isolated submaximal exercise sessions. 10 weeks apart. Blood was collected during each session to measure erythrocyte membrane fluidity (EM F), paraoxonase-1 (PON 1) activity, plasma malondialdehyde (MDA) and vitamin E concentrations. These biomarkers were measured in venous blood samples collected before (t(0)), just after (t, EMF only) and 1d (t + 1d) and 7d (t + 7d) after the dogs ran on a treadmill. Prior to vitamin E Supplementation. exercise induced a significant decrease in PON1 activity, EM F, vitamin E concentration and a significant increase in MDA concentration at t + 1d. After a 10 week vitamin E supplementation period, these exercise-induced changes in PON1 activity, EMF and MDA concentration were still significant in the control group, but not in the Supplemented group. These results Suggested that vitamin E Supplementation had it protective effect on submaximal exercise-induced oxidative damage in sedentary dogs. (C) 2008 Elsevier Ltd. All rights reserved.