Study On The Damage Effect Of PM_1.0 On Cells And ICR Mice

Atmospheric particulate mattersplay the key role in inducing the smogs which are harmful to the human health.The atmospheric submicron particles(Particulate Matter1.0,PM_1.0)account for about 60%to 70%of PM_2.5,which is closely related to the human health.In this study,human bronchial epithelial cells?BEAS-2b cells?and ICR mice were selected as subjects for exposure to oxidative damage and inflammatory effects of submicron particles and their components in vitro and in vivo.The collected PM_1.0 was made into a whole particle component,dissolved in serum components,insoluble in serum components,and sample dissolved in PBS component,and exposed to BEAS-2b cells to measure cell activity and intracellular ROS levels,SOD activity and GSH/GSSG,study the effects of different component samples on cell damage.The different components of PM_1.0.0 inhibited the cell activity by the following order:PM_1.0>serum-soluble components>serum-insoluble components>PBS-soluble components.After the BEAS-2b cells exposd to the different components of PM_1.0,the intracellular ROS levels were significantly increased compared to the control group.The effect of serum insoluble components on the ROS production was significantly weaker than that of other components.The relative activity of SOD was increased with the increase of exposure concentration.The different components of PM_1.0enhanced the SOD activity by the following order:PM_1.0>serum-insoluble components>serum-soluble components>PBS-soluble components.The GSH/GSSG ratio presented a significant decrease with the increase of exposure concentration.The GSH/GSSG induced by the total particlesdecreased most significantly,followed by the serum-soluble component.Furthermore,it was found that the intracellular ROS level was initially increased and then decreased during the exposure duration?3-15h?.The ICR mice were used to expose submicron particles in the atmosphere.The aerosols made by PM_1.0.0 were studied for subchronic toxicity in mice.It was found that the skin and fur of each group were not abnormal,the activity was slightly weakened,and no mice died.Anatomical observation of the mice pathological section of the lung revealed that there were a large number of inflammatory cell infiltration in the exposed group.The epithelial cells appeared to fall off and particles were suspected to be present.The higher exposure concentration,the more serious damage oftissures.The ratio of GSH/GSSG in the serum and lung tissues of the test mice was lower than that of the control group?P<0.05?,and the GSH/GSSG decreased significantly with the increase of the exposure concentration,especially in high concentration group?P<0.05?.The ratio of GSH/GSSG in lung homogenate of test mice was lower than that of control group,and the difference was statistically significant?P<0.05?,which was consistent with the change trend of GSH/GSSG in serum.In addition,the fluorescence intensity of ROS in lung tissue of mice increased with the increase of exposure concentration.With the increase of exposure concentration,the levels of inflammatory factors including TNF-?,IL-6 and IL-17 in serum and lung tissue were increased.The levels of IL-6 and IL-17 were significantly higher than those of the control group?P<0.05?.The level of inflammatory inhibitor IL-10 was significantly decreased with the increase of exposure concentration compared to the control group?P<0.05?.The level of inflammatory factors in lung tissue was significantly higher than that in serum,and the level of anti-inflammatory factor IL-10 was higher than that in serum as well.