The effect of air pollutants on the microecology of the respiratory tract of ratsâ˜

- We established the poisoning rat model exposed to mixed air pollutants.
- Decrease of microflora and increase of pathogenic microorganisms were detected.
- Pathogenic microorganisms were correlated with expression of TNF-α and IL-6.
- Use rat model to assess the effects of mixed air pollutants on the respiratory tract.

To study the effect of air pollution on the microecology of the respiratory tracts and the relationship of the biotopes with respiratory diseases, Wistar rats exposed to mixed air pollutants were used as poisoning models. The bacterial floras of respiratory tract were analyzed as well as expression of pro-inflammatory mediators of the respiratory epithelium. The mRNA and protein expression levels of pro-inflammatory factor and cytokines measured showed that there were significant changes in the microbiocenosis of the respiratory tract. The microorganisms underwent quantitative and qualitative changes following exposure to mixed air pollutants including a decline of indigenous microflora and increase of the content of conditionally pathogenic microorganisms. These changes depended on the degree of air pollution severity. Measurement of pro-inflammatory factors CC16, TNF-α and IL-6 revealed a similar time-dependent relationship between the content of conditionally pathogenic microorganisms and the interference of CC16 secretion, as well as up-expression of TNF-α and IL-6.