Age and exercise-related changes in lipid peroxidation and superoxide dismutase activity in liver and soleus muscle tissues of rats.

Thiobarbituric acid-reactive substances (TBARS) level, as marker of lipid peroxidation, and superoxide dismutase (SOD) activity, as endogenous antioxidant enzyme, were examined in liver and soleus muscle tissue of young and old male Wistar rats. We established different types of exercise running on a treadmill both for young and old rats, investigated the effect of aging, exhaustion and training on these groups. The hepatic TBARS levels were raised in the short-training young group and in the long-training old group. On the other hand, the TBARS content decreased in soleus muscle in the short-training young group, and long-training exercise enhanced lipid peroxidation in old rats. SOD activity increased in liver in short-training group. while this activity showed the lowest values in long-training old rats. With respect to soleus muscle tissue, SOD activity was elevated after exhaustive exercise in young rats and old rats had the highest activity in the long-training old group. These findings suggest that free radicals play a role in aging and that the different type, intensity and duration of exercise modify the lipid peroxidation level and antioxidant enzyme activity.