DAMAGE OF DIFFERENT PM 2.5 CONCENTRATIONS IN SPORTS VENUES TO THE BODY'S IMMUNE SYSTEM

Xun Xu^*

Department of Physical Education and Research, Huzhou Vocational & Technical College, Huzhou, 313000, China

Objective: To investigate the damage of different PM 2.5 concentrations in sports venues to the body’s immune system. 

Methods: PM 2.5 particles were collected using a medium flow sampler and prepared into suspension. 36 male Wistar SPF (specific pathogen-free, SPF) rats were selected and classified into the control group, low dose (5 mg·kg^-1), medium dose (10 mg·kg^-1), and high dose (15 mg·kg^-1) groups. Low, medium and high doses of PM 2.5 (respectively 5, 10, 15 mg/kg) were given by intratracheal instillation to establish a non-exposure lung injury model in rats. After one-time intratracheal installation, perform progressive loading treadmill training, and anesthetize the animals after 3 d. Collect macrophages in bronchoalveolar lavage fluid (BALF), and detect the hypersensitive C-reactive protein (hs-CRP), IL-10, IL-1β, and rat macrophage inflammatory protein 1α (MIP-1α), Clara cell protein (CC16) and neutrophil elastase (NE) expression levels in BALF by enzyme-linked immunoassay (ELISA); detect the contents of IgA, IgM, IgG, and complements C3, C4, C5 in BALF. 

Results: Compared with the control group, as PM 2.5 administration concentration increased, MCP-1, MIP-1α, hs-CRP, IL-10 and IL-1β increased in a dose-dependent manner, while NE and CC16 decreased in a dose-dependent manner, showing statistically significant differences (P<0.05). IgM and IgG contents in BALF were significantly higher compared with the control group, but IgA content change was not statistically significant. Complement C3, C4 and C5 contents in BALF were significantly higher compared to the control group. There was no significant difference between the low and middle dose groups and the control group (P>0.05). 

Conclusion: PM 2.5 intratracheal instillation destroys the homeostasis of the immune system in rats. Regular exercise can maintain the immune system balance and enhance the body's resistance to PM 2.5.