Effects Of Combined Exposure To Formaldehyde And PM2.5 On Brain Of Balb/c Mice Asthma Model

Epidemiological studies have shown that there is a link between asthma and brain damage,but toxicological studies have not fully confirmed yet,especially the effects of asthma on the brain.Environmental pollutants have impact on asthma but previous studies have focused on the impact of single contaminant,ignoring the effects of mixed contaminants.In order to examine any brain damage resulting from combined exposure to formaldehyde(FA)and PM2.5 on asthmatic mice,30 male Balb/c mice were divided randomly into 5 groups:(1)Saline group;(2)OVA group;(3)FA+OVA group;(4)PM2.5+OVA group and(5)FA+PM2.5+OVA group.First the allergic asthma model was established and then the mice were exposed to formaldehyde through gas inhalation at a concentration of 3.0 mg/m3for three hours every day for 18 days,and with PM2.5 at a.concentration of 0.1 mg per mouse three times a week.The mice were exposed to PM2.5,a typical outdoor air pollutant and formaldehyde,a typical indoor air pollutant to be closer with the true environment.After 25 days,cerebral brain tissue homogenates were prepared and the brain coefficient was calculated.Oxidative stress(reactive oxygen species[ROS],glutathione[GSH]and malondialdehyde[MDA]),brain histopathological examination and inflammation(nuclear factor ?B[NF-?B],interleukin-1?,interleukin-6)were assessed to explore the effects of allergic asthma on brain tissue.The results showed.that allergic asthma can cause damage to the brain through oxidative stress.The results also showed that exposure to formaldehyde and PM2.5 will increase the damage caused by allergic asthma to the brain.This may be mediated by oxidative stress and NF-?B activation,which promote the release of the inflammatory factors and resulting in increased inflammation.