Swim training does not protect mice from skeletal muscle oxidative damage following a maximum exercise test

Abstract

We investigated whether swim training protects skeletal muscle from oxidative damage in response to a maximum progressive exercise. First, we investigated the effect of swim training on the activities of the antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), in the gastrocnemius muscle of C57Bl/6 mice, 48 h after the last training session. Mice swam for 90 min, twice a day, for 5 weeks at 31°C (± 1°C). The activities of SOD and CAT were increased in trained mice (P < 0.05) compared to untrained group. However, no effect of training was observed in the activity of GPx. In a second experiment, trained and untrained mice were submitted to a maximum progressive swim test. Compared to control mice (untrained, not acutely exercised), malondialdehyde (MDA) levels were increased in the skeletal muscle of both trained and untrained mice after maximum swim. The activity of GPx was increased in the skeletal muscle of both trained and untrained mice, while SOD activity was increased only in trained mice after maximum swimming. CAT activity was increased only in the untrained compared to the control group. Although the trained mice showed increased activity of citrate synthase in skeletal muscle, swim performance was not different compared to untrained mice. Our results show an imbalance in the activities of SOD, CAT and GPx in response to swim training, which could account for the oxidative damage observed in the skeletal muscle of trained mice in response to maximum swim, resulting in the absence of improved exercise performance.

Studies on the Antifatigue Activities ofCordyceps militarisFruit Body Extract in Mouse Model

“…Antioxidant enzymes including GSH-Px and SOD play important roles in preventing oxidative injury in animals [ 18 , 19 ]. Overproduction of a large amount ROS leads to oxidative stress and deleterious effects on tissue [ 20 ].…”

Increased Migratory and Activation Cell Markers of Peripheral Blood Lymphocytes in an Experimental Model of Nephrotic Syndrome

“…Fragments were weighed after thawing and macerated/homogenized with PBS. Redox status was assessed using a method employed elsewhere [ 26 ]. Briefly, tissue levels of thiobarbituric acid reactive substances (TBARS), which include malondialdehyde (MDA), were determined by reaction under acidic conditions (90°C for 90 minutes) and analyzed on a microplate (532 nm).…”

“…Absorbance was measured on a microplate (420 nm). The Bradford method was used to determine the protein concentration with bovine serum albumin as the standard [ 26 ].…”

Antioxidant and Antifatigue Activities of Polygonatum Alte-lobatum Hayata Rhizomes in Rats

“…Antioxidant enzyme system helps protect against excessive or exhaustive exercise-induced oxidative damage and relates to physical status of athletes [ 6 ]. Antioxidant enzymes such as glutathione peroxidase, catalase, and superoxide dismutase (SOD) play important roles in preventing oxidative injury in vivo [ 7 , 8 ]. In high intensity or exhaustive exercise, overproduction of a large amount reactive oxygen species (ROS) could lead to oxidative stress and deleterious effects on tissue [ 9 , 10 ], and modulation of antioxidant enzymes activity may alleviate exercise-induced oxidative stress and body fatigue.…”