Os efeitos do exercício físico agudo e crônico sobre marcadores imunes da polarização de células th1 / th2 em adultos e idosos: uma revisão sistemática

Abstract

Introduction: Acute and chronic physical exercise provokes a deviation of organic homeostasis that leads to the reorganization of the responses of several systems, including the immune system. Th1 and Th2 helper lymphocytes are effector cells that produce distinct sets of cytokines that are responsible for modulating important actions of the immune system. Physical exercise can be an efficient and low-cost strategy to promote the balance between Th1 and Th2 markers. However, we did not find systematic reviews that analyzed the association between physical exercise and polarization markers of Th1 and Th2 cells. Objective: To examine the impact of acute and chronic exercise on Th1 and Th2 cell immune markers in healthy adults and elderly. Methods: We performed a systematic review following PRISMA recommendations. We searched the databases (MEDLINE - PubMed, EMBASE, Scopus, Web of Science and Science Direct) for randomized controlled clinical trials and prospective observational studies that analyzed immune markers of Th1 and Th2 cells, of which 28 publications were included in which groups who underwent the intervention (exercise) were their own controls (pre and post intervention) and the studies that performed the comparison between groups, with a grand total of 700 participants. Studies involving animals or isolated cells, patients with diseases, exposure to medications or drugs, patients with immunodeficiencies or publications that did not meet the inclusion criteria of this review were excluded. The quality of the selected studies was examined using the Cochrane risk of bias tool (ROB2), generating data that were grouped and presented in tables and figures. Results: An acute session of cyclical exercises or strength training in healthy elderly people promoted a significant increase in serum concentrations of IL-4, IL-6 and IL-10 immediately afterwards, returning to pre-exercise values within 1 hour after an exercise session at moderate to high intensities. In chronically elderly people, strength training or cyclic exercises at moderate to high intensities decreased serum concentrations of TNF-α, IL-6 and the CD4/CD8 ratio and increased IL-10 after 24 weeks. In healthy adults, a session of cyclic exercise at moderate to high intensities increased serum concentrations of IL-6, IL-10 and IL-12 immediately after the session and decreased IL-6 to baseline (pre-exercise) levels after 1 hour and 30 minutes and IL-12 after 2 hours after the end of the session. Chronically in adults, the studies did not show significant effects on IL-6 and IL-10 and the other markers were not analyzed. Final considerations: The data compiled from the studies included in this review suggest that one session (acute response) in the various exercise modalities performed at moderate to high intensities does not cause damage to the balance of Th1 and Th2 cells, but can stimulate modulation and cell renewal lymphocyte producing biopositive effects in adults and the elderly. Physical training (chronic response) also in several modalities at moderate to high intensities, can promote rebalancing between Th1 and Th2 cells, decreasing the systemic inflammatory state that can be induced by aging, chronic diseases or infections.