Role Of PM2.5 On The Expression Of Tight Junction Protein Occludin In Nasal Epithelial Cells

ObjectiveTo observe the effect of PM2.5 on the distribution and expression of Occludin in normal human nasal epithelial cells.MethodsWe selected the normal human nasal epithelial cell line HNEpC as the research object.And treat cells with a 24 hour and 48 hour exposure to different concentrations of PM2.5 in vitro,choose 200?g/ml?400?g/ml?500?g/ml as experiment group for Follow-up experiments.Cell viability was determined by CCK-8 assay.The Occludin expression on the level of protein and mRNA was determined by Immunofluorescence assay,Western-Blot and real-time fluorescence quantitative PCR.ResultsCompared with the control group,the cell viability of nasal epithelial cells was decreased after 24h and 48h PM2.5 stimulatation(F_24h=36.25?F_48h=20.26,P<0.001),and the cell viability was negatively correlated with PM2.5concentrations;The results of Immunofluorescence assay showed thatthe cells in the control group were round and closely arranged.The Occludin was honeycomb-shaped,evenly distributed and closely connected.The morphology of the 200?g/ml PM2.5group was slightly longer than that of the control group,and the Occludin distribution was not significantly changed.The 400?g/ml group The number of cells was slightly lower than before,and the cell morphology was slenderer than before,and a small amount of vacuoles appeared between the cell membrane and the cell junction.In the500?g/ml group,the number of cells in the visual field was significantly reduced,and the morphology was more than before.Slender,long spindle-shaped,a large number of vacuoles in the cell membrane,and Occludin structure interruption.;The results of Western-Blot and real-time fluorescence quantitative PCR showed that compared with the control group,the relative expressions of Occludin and mRNA in the other groups were all down except the 24h-200?g/m group,and the Occludin expression of 24hour and 48hour had a time-effect relationship.ConclusionPM2.5 can reduce the viability of HNEpC in normal human nasal epithelial cell line,and reduce the mRNA and protein expression of the intercellular tightly connexin Occludin,promoting the occurrence of allergic rhinitis.