Oxidative Stress and Hemodialysis: The Role of Aerobic Exercise Training on the Various Laboratory Parameters

Abstract

Background: Oxidative stress (OS) and inflammation are common factors in patients with chronic kidney disease and increase the risk of cardiovascular disease (CVD) and death in these patients, particularly in hemodialysis (HD) cases. Exercise training is a therapeutic approach to reduce morbidity and mortality in these patients. The purpose of this study was to determine the effect of aerobic exercise training on OS factors in HD patients. Methods: This case-control study was performed over one year (From March 2019 to February 2020) at Kerman (south of Iran). Nineteen outpatient HD patients participated in an aerobic exercise training program during HD. Cycling was performed by mini-cycle in the first hour of HD, pedaling was started with the least tolerable time by the patients, and increased up to three-quarters of an hour based on the patient’s tolerance, three times a week for eight weeks. Also control group, 18 outpatient HD patients were selected and did not enter the exercise training program. Blood samples were collected before and after the intervention in both groups. Inflammatory factors such as albumin (Alb), C-reactive protein (CRP), ferritin, white blood cell (WBC) as well as, oxidative and nitrogenous factors such as malondialdehyde (MDA), carbonyl groups, uric acid, and ionic regenerating capacity were measured. Chi-square and independent t test were used to analyze the data and compare the two groups. Results: There were no significant differences in CRP, Alb, and uric acid between the two groups. In the test group, variables such as total antioxidant capacity (TAC), glutathione (GSH), protein carbonyl (PC), lipid peroxidation (LPO) products, ferric reducing ability of plasma (FRAP), and thiobarbituric acid reactive substances (TBARST) showed a significant difference after the intervention. The values of TAC, GSH, and FRAP in the case group were significantly higher than the same values in the control group (P≤0.0001 for all), but PC (P≤0.006) and TBARS (P≤0.026) values were higher in the control group after the intervention. The intervention had no effect on Alb and ferritin. But, uric acid levels decreased significantly in both groups after the intervention. In the case group, TAC, GSH, and FRAP increased (P=0.0001 for all), but PC, LPO, and TBARST decreased (P=0.0001, P≤0.03, and P≤0.02 respectively). Conclusion: The results of the present study showed that aerobic exercise training had no effect on inflammatory factors such as CRP, ferritin, and Alb.