Twice-weekly exercise training reduces oxidative stress and proinflammatory cytokine levels in elder women

Aim: Reactive oxygen species and high concentrations of proinflammatory cytokines are related to diseases that are often triggered during the aging process. This study aimed to investigate the effect of moderate-intensity physical exercise, twice a week, on oxidative stress and inflammation biomarkers. Methods: Participants were older women aged 60-70 years, engaged in a moderate-intensity exercise program carried out in 60 minutes sessions, twice a week, for 24 weeks. Exercise sessions consisted of step, resistance and stretch exercises. Thiobarbituric acid reactive substances (TBARS), serum iron and cytokines IL-6, IL-1β and IL-1ra were determined using specific kits. Physical fitness was assessed using tests provided by AAPHERD. A paired t test was performed. Results: Moderate-intensity exercise program provided a reduction in lipid peroxidation (27%) and in the serum release of prooxidant iron ions (40%). Cytokine levels were reduced by 37% for IL-6, 16% for IL-1β and 32% for IL-1ra. Improvements in cardiorespiratory fitness (13%), muscular endurance (11%) and flexibility (12%) were also observed. Conclusion: Diminished redox state and inflammation were obtained using a twice-weekly exercise program. These results have important implications for older adults who are unable or unwilling to attend exercise programs more than twice a week. Moreover, these results could re-establish the minimum exercise activity necessary for obtaining health benefits in the elderly population.(AU)

Estresse oxidativo e envelhecimento: papel do exercício físico / Oxidative stress and aging: role of physical exercise

Dentre as várias teorias que procuram explicar o processo de envelhecimento, a teoria das espécies reativas de oxigênio (EROs) tem apontado evidências experimentais significativas, sugerindo que o envelhecimento é o resultado do acúmulo de ações tóxicas causadas pelas EROs que podem ocasionar danos ao DNA celular, aos lipídios e as proteínas. Existem evidências de que a produção das EROs durante o exercício físico não pode ser modificada pelo treinamento regular, mas é possível que o metabolismo celular endógeno aumente suas defesas antioxidantes. Assim, o objetivo dessa revisão de literatura é apresentar os principais mecanismos de produção das EROs e os mecanismos de defesa antioxidante, assim como as adaptações induzidas pelo exercício físico que atuam como uma proteção contra os danos provocados pelo estresse oxidativo.

Different theories have been developed to explain the aging process and the Free-radical Theory of Aging had shown significant evidence that aging is the result of ROS toxicity action that lead to cellular DNA injury, lipid and protein oxidation. While during exercise session a major oxygen consumption increases ROS production, an adaptation occurs at cellular level and antioxidant enzymes concentration or activity are increase. Therefore, this review aims to show the mainly mechanisms of ROS generation and antioxidant defense mechanisms, as well the adaptations induced by physical exercise that act as a protection against oxidative stress related-injuries.