Introduction: Effects of physical activity on immune functions may largely depend on the type of activity, its intensity and duration. However, little information is available regarding the immunological effects of sporting activities in older ages.
The aim of our study was to examine the changes in a wide spectrum of lymp...hocyte subtypes after a period of regular workout among healthy women of different ages.
Methods: In our study, we enrolled 16 elderly women (between ages of 60-75 years) formerly not engaged in regular physical activity, who took part in lightweight conditioning gymnastic exercise program. Eight young athletes and 26 young adults with sedentary lifestyle served as controls. The percentages of peripheral NK, NKT cells, T and B lymphocyte subtypes were determined by flow cytometry based on the staining of extracellular markers and intracellular cytokines.
Results: Lymphocyte subgroups did not differ between the groups of young athletes and young adults with sedentary lifestyle. However, in elderly women, levels of NKT cells were lower, while ratios of T helper / T cytotoxic cells were higher compared to younger individuals. At the end of exercise program, in elderly women, percentages of naive B cells decreased, while levels of switched-memory B cells increased. Furthermore, proportions of Th2 cells increased, while levels of immunosuppressive CD4+CD127-CD25bright Treg cells decreased as the result of regular exercise.
Conclusion: Differences observed after lightweight exercise programs reflect a presumably enhanced immunoreactivity and increased ability for immune responses in older ages.
Physical activity and exercise are especially important in maintaining health and reducing risk of many diseases. Exercise leads to a pronounced immunomodulation by affecting the elements of innate immune system, as well as the ratio and functions of neutrophils, macrophages, natural killer cells, which are involv...ed in the development, maintenance and elimination of inflammation. In the adaptive immune system, Th1 / Th2 balance shift toward Th2, and high-intensity training causes an increase in the proportion of regulatory T cells, as opposed to the effect of non-strenuous exercise on the Treg cell ratio. In response to exercise, there is a lack of data on B cells, but some studies have reported a decrease in immunoglobulin secretion. In our own research we observed changes in naive and memory B cell ratios. Upon exercise, IL-6, as proinflammatory cytokine, promotes T cell proliferation, activation, and differentiation of B cells into antibody-producing plasma cells. Hormonal factors play an important role in the background of immunological changes. Exercise stimulates the secretion of both adrenaline and noradrenalin, and their concentration in the blood is directly proportional to the duration of exercise. Endurance exercise is associated with increased cortisol levels, while low intensity exercise does not significantly affect cortisol levels. Exercise and physical stress can increase the concentration of endorphins by 3 to 10 times; β-endorphin inhibits T and B cell activity, thus reduces antibody production. Testosterone causes a reduction in antibodies to IL-4, IL-5, IFN-γ, Ig-M and Ig-G. Based on the above, mild to moderate physical activity contributes to the enhancement of immune reactivity and the immune response. On the other hand, strenuous exercise with increased intensity leads to a deterioration of immune function and impaired immunological defense.