Physical Exercise Training Improves Judgment and Problem-Solving and Modulates Serum Biomarkers in Patients with Alzheimer's Disease

Abstract

Alzheimer's disease (AD) is characterized by progressive impairment of memory, with an etiology involving oxidative stress and inflammation. Exercise training is a safe, efficacious, and economic approach to manage neurodegenerative diseases. In AD, the biomarkers of oxidative damage to lipids, proteins, and DNA are elevated. In the present study, we aimed to evaluate whether exercise is effective in patients with AD by assessing the serum biomarkers associated with the redox status, neurotrophin levels, and inflammatory system. This nonrandomized clinical study (n = 15) involved 22 training sessions performed twice a week (60 min/session) in patients diagnosed with AD. The cognitive and self-awareness tests were performed 48 h before and after the physical training session. In patients with AD, physical training significantly improved the judgment and problem-solving domains of the memory score; however, general mental health, memory, orientation, and home/hobby domains were improved slightly, and the neurotrophin levels remained unaltered. Significantly, the markers of protein integrity also increased following exercise. Furthermore, catalase activity and ROS levels decreased, nitrite levels increased, and interleukin-4 level increased following physical training in patients with AD. Although proinflammatory cytokines remained unaltered, the levels of neuron-specific enolase, a marker of neuronal damage, decreased following exercise training in these patients. In conclusion, physical exercise training could be a safe and effective method for blocking the AD progression and improving the antioxidant capacity and anti-inflammatory system, whereas certain assessed biomarkers could be utilized to monitor AD therapy.

Keywords: Catalase; DCFH; Learning and memory; Neuroinflammation; Neurotrophins; Nitrite; Oxidative stress.