Age-related changes and effects of regular low-intensity exercise on gait, balance, and oxidative biomarkers in the spinal cord of Wistar rats

Abstract

The present study aimed to analyze age-related changes to motor coordination, balance, spinal cord oxidative biomarkers in 3-, 6-, 18-, 24-, and 30-month-old rats. The effects of low-intensity exercise on these parameters were also analyzed in 6-, 18-, and 24-month-old rats. Body weight, blood glucose, total cholesterol, and high-density lipoprotein (HDL) cholesterol were assessed for all rats. The soleus muscle weight/body weight ratio was used to estimate skeletal muscle mass loss. Body weight increased until 24 months; only 30-month-old rats exhibited decreased blood glucose and increased total cholesterol and HDL cholesterol. The soleus muscle weight/body weight ratio increased until 18 months, followed by a small decrease in old rats. Exercise did not change any of these parameters. Stride length and step length increased from adult to middle age, but decreased at old age. Stride width increased while the sciatic functional index decreased in old rats. Performance in the balance beam test declined with age. While gait did not change, balance improved after exercise. Aging increased superoxide anion generation, hydrogen peroxide levels, total antioxidant capacity, and superoxide dismutase activity while total thiol decreased and lipid hydroperoxides did not change. Exercise did not significantly change this scenario. Thus, aging increased oxidative stress in the spinal cord, which may be associated with age-induced changes in gait and balance. Regular low-intensity exercise is a good alternative for improving age-induced changes in balance, while beneficial effects on gait and spinal cord oxidative biomarkers cannot be ruled out because of the small number of rats investigated (n=5 or 6/group).

Differences in Body Composition of Upper and Lower Limbs in Elite Taekwondo Athletes

“…However, the study limitation relates to the lack of investigation into the extent of injury and current recovery status. In addition, previous animal studies have shown that the ability for balance decreases with age (Silveira et al, 2019), and no such correlation was found in this study. Additional research is needed to analyze the differences between balance and performance, and age and sex in professional athletes.…”

Aging and low-intensity exercise change oxidative biomarkers in brain regions and radiographic measures of femur of Wistar rats

“…To characterize the effect of aging on brain biomarkers, 47 intact 3-monthold male Wistar rats were obtained from a colony maintained by the Universidade Federal do Rio Grande do Sul. In the laboratory, the rats were housed in groups of three per conventional cage, maintained at 22 ± 2°C, exposed to a 12-h light/dark photoperiod, and provided free access to food and water, as previously described by Silveira et al (17). Briefly, six (n=6) of the rats were acclimated for one week and euthanized by decapitation.…”

“…The animals were classified as young adult (3 months), adult (6 months), middle-aged (18 months), young elderly (24 months), and old (30 months) (17). These ages were chosen because they correspond to human ages of 18, 45, 60, and 75 years, respectively (17,18).…”

“…To characterize the effect of regular low-intensity exercise on brain oxidative biomarkers, rats were randomly selected for an exercise program at ages of 3, 15, and 21 months. The exercise program was carried out for 12 weeks (17). Thus, rats at ages 3, 15, and 21 months exercised until ages of 6, 18, and 24 months, respectively.…”

“…Nevertheless, the effect appears related to training duration and intensity (15,16). Recent research showed that lowintensity exercise ameliorated performance of aged rats in the beam balance test, a test that assesses simple (static) equilibrium (17). However, the effects of low-intensity exercise on changes in oxidative stress biomarkers in different regions of the brain remain unknown, especially in regions with important roles in motor control.…”