Effect of Exercise Training on Antioxidant and Metabolic Functions in Senescent Rat Skeletal Muscle

Abstract

Aging is known to be associated with alterations of both oxidative capacity and antioxidant status in skeletal muscle. In the present investigation we compared the activity of enzymes involved in both metabolic functions and antioxidant defense capacity in young adult (5 months old) and senescent (27.5 months old) Fischer 344 rats. In addition, we studied the effects of chronic exercise training on these enzymes in the senescent skeletal muscle. Old sedentary rats had significantly lower glutathione peroxidase (GPX) activity (––22%, p < 0.05) in the deep portion of vastus lateralis muscle (DVL) than young sedentary rats, but after a progressive 10-week treadmill training program GPX activity in DVL was significantly increased in old rats to a level higher than that seen in young sedentary rats. Superoxide dismutase and catalase activities in the DVL were not altered significantly with aging or by training. Glutathione S-transferase activity in the same muscle was elevated (p < 0.05) with aging but unaffected by training. Citrate synthase and malate dehydrogenase activities in the DVL muscle were significantly decreased in senescence, whereas training increased these two enzyme activities by 71 and 48%, respectively (both p < 0.05). Lactate dehydrogenase activity in the same muscle decreased with age but increased 23% (p < 0.05) in old rats. These data indicate that while aging may significantly affect antioxidant and metabolic capacities in skeletal muscle, regular exercise can preserve functions of these enzyme systems at old age.

Interaction of vitamin E and exercise training on oxidative stress and antioxidant enzyme activities in rat skeletal muscles

“…On the other hand, an elevated SOD activity was reported in deep vastus lateralis, but not in soleus after 10 weeks of aerobic training [23]. Some other studies reported no change in SOD activity after regular training [24,25]. The inconsistent results from previous studies may at least partially result from different antioxidant status of the experimental animals, as the current study showed a significant vit Etraining interaction effect on SOD activity in both muscles investigated.…”

“…The adaptation appeared to vary in different muscles [21][22][23]. However, contradictory results of the exercise effect on antioxidant enzymes do exist [24,25].…”

Colostrum supplementation protects against exercise - induced oxidative stress in skeletal muscle in mice

“…Antioxidant supplementation had also shown a significant impact on lipid peroxidation in highly trained athletes or over-trained athletes, and also had helped to increase the antioxidants level in intermittent players [19,26-29]. …”

The Physiology and Biochemistry of Skeletal Muscle Atrophy as a Function of Age

“…(81) did not affect the activities of these enzymes (81,82). Glutathione peroxidase (GPX), on the other hand, was shown to decrease with age and increase after 10 weeks of treadmill running (81). However, in a recent report by Ji (82) all antioxidant enzymes like SOD, GPX, Cat, and glutathione reductase were shown to increase significantly after an exhaustive bout of exercise (83).…”

“…The conclusion drawn from this last study was that exercise prevented age-related atrophy of weight-bearing soleus and not of the non-weight-bearing EDL muscle. (81) did not affect the activities of these enzymes (81,82). Glutathione peroxidase (GPX), on the other hand, was shown to decrease with age and increase after 10 weeks of treadmill running (81).…”