Effect Of Aerobic Exercise And Different Levels Of Pm 2.5 On Pulmonary Response In Wistar Rats

Abstract

PURPOSE: Exposure of particulate matter of less than 2.5μm (PM2.5) has been associated with adverse respiratory and the risk of inflammation. While regular physical activity (PA) reduces the risk of many adverse health effects. This study aimed to examine the protection of exercise on adverse pulmonary health induced by PM2.5 exposures in rats. METHODS: 80 Wistar rats were randomly divided into 8 groups: Sedentary (S), Exercise (E), Sedentary+ Low concentration PM2.5 exposures (S+LPM), Exercise+Low concentration PM2.5 exposures (E+LPM), Sedentary+Medium concentration PM2.5 exposures (S+MPM), Exercise+ Medium concentration PM2.5 exposures (E+MPM), Sedentary+High concentration PM2.5 exposures (S+HPM), and Exercise+ High concentration PM2.5 exposures (E+HPM). The rats in all E-related groups went through 8-week aerobic interval treadmill training (5 days/week,1h/day). The PM-related groups of rats were exposed to different concentration PM2.5 exposure in Beijing. After one bout of PM exposure, the pulmonary function, structure of lung tissues and several pulmonary biomarkers were observed. RESULTS: 1) Compared with S group, following changes occurred in various S+PM2.5 exposure groups: lung tissues were seriously damaged, local bleeding, pus exudation, and inflammatory cell infiltration, as well as the decline of the SOD (S+LPM: P=0.020, S+HPM: P=0.370), and CAT (S+HPM: P=0.012) while the incline of Penh (S+MPM: P=0.133, S+HPM: P=0.002), MDA (S+HPM: P=0.007), TNF-α (S+MPM: P=0.018, S+HPM: P=0.008 ) and IL-1β (S+HPM: P=0.014) were observed. 2) Compared with the corresponding different concentration of S+PM2.5 exposure groups, the bleeding and inflammatory infiltration were improved, the Penh (E+HPM: P=0.005), TNF-α (E+HPM: P=0.042) and IL-1β (E+HPM: P=0.036) were decreased and CAT (E+HPM: P=0.039) and GSH (E+HPM: P=0.040) were increased in related E+PM groups respectively. CONCLUSIONS: The aerobic interval training improved the pulmonary function and impeded the lesion progression, which is due to effective in impeding the oxidative stress and inflammation.