Effects of long-term Tai Chi vs. aerobic exercise on antioxidant activity and cognitive function in individuals with Parkinson’s disease

Abstract

An imbalance between the generation of reactive oxygen species and the body’s antioxidant defense mechanisms is closely related to the development and progression of Parkinson’s disease (PD). Considering that physical exercise is a potential therapeutic intervention for modulating oxidative stress markers and cognitive function in PD, the primary purpose of this study was to compare the effects of different long-term exercise modalities on antioxidants and cognitive performance in patients with PD. In addition, the secondary purpose was to explore whether changes in the levels of these biochemical markers are associated with alterations in cognitive performance pre- and post-intervention. In all, 61 participants were randomly divided into the aerobic exercise (AE, n=20), Tai Chi exercise (TCE, n=21), or control (n=20) group. Blood samples were collected before and after a 12-week intervention period for the analysis of antioxidant markers [leukocyte 8-hydroxydeoxyguanosine (8-OHdG), catalase (CAT), glutathione (GSH), glutathione peroxidase (GSH-Px), oxidized glutathione (GSSG), superoxide dismutase (SOD), and uric acid (UA)]. Cognitive function was evaluated using the Mini-Mental State Examination (MMSE). Although no significant changes were observed in the activity of 8-OhdG, GSH-Px, GSSG, GSH:GSSG ratio, SOD, and cognitive performance in the AE and TCE groups, the 12-week AE intervention led to a significant increase in CAT and GSH levels, along with a significantly decrease in UA levels among individuals with PD. Conversely, the TCE intervention resulted in a significant increase in GSH levels. However, SOD activity and MMSE scores were significantly decreased after 12 weeks in the control group. The correlations between changes in MMSE scores and changes in the levels of GSH and UA prior to and after the intervention reached significance in the AE group. Thus, long-term AE and TCE might serve as effective strategies for reducing oxidative damage and preserving cognitive function in PD, with AE exhibiting greater benefits compared with TCE. These findings hold potential clinical relevance as complementary measures to standard medical treatments and alternative therapies, such as antioxidant supplements and dietary adjustments, particularly for individuals in the early stages of PD.