Effect of aerobic intermittent exercise on the decreased cognitive ability induced by PM2.5 exposure in rats

Abstract

Abstract Objectives This study aimed to investigate the protective effects and underlying mechanisms of aerobic intermittent exercise on cognitive impairment by PM2.5 exposure. Methods Thirty-two rats were randomly divided into four groups: sedentary, exercise, sedentary + PM2.5 exposure, and exercise + PM2.5 exposure. The exercise groups underwent 8 weeks of exercise training (5 days of exercise per week). Subsequently, PM2.5 exposure groups were subjected to PM2.5 for three weeks. Post-exposure, we assessed cognitive abilities (shuttle box test), hippocampal tissue structure, related inflammatory factors (TNF-α, IL-6, IL-1β), the protein of inflammatory responses mechanism (P65, IκκB) and cognitive-related protein levels (BDNF, Aβ-42). Results PM2.5 exposure caused cognitive impairment, abnormal histopathological changes, reduced cognitive related protein and increased pro-inflammatory cytokine levels. Analysis of shuttle box test data revealed significant main effects on the passive avoidance latency times measured in rats (p<0.05). Aerobic intermittent exercise improves spatial learning decline in rats induced by PM2.5. Conversely, the Exercise + PM2.5 group demonstrated a significant reduction in latency of 24.9 % compared to the Sedentary + PM2.5 group (p<0.05, ES=1.41). Conclustion Aerobic intermittent exercise may help in protecting against the decrease of cognitive ability induced by PM2.5 exposure.