Assessing the Adverse Impacts of PM_(2.5)on Olfactory System Using an Air-liquid Interface Culture Model of Primary Olfactory Epithelial Cells

The air-liquid interface(ALI)culture is a kind of recently developed system,which has proved its availability in simulating the biology of respiratory tract epithelial tissues.In this study,an ALI-based mouse primary olfactory epithelial cell(OEC)model was established to perform the exposure of PM_(2.5)(PM=particulate matter)collected from Dianshan Lake(Shanghai)and Wangdu(Hebei).The results showed that PM_(2.5)in both regions caused a decrease in cell viability in a dose-dependent manner.The 0.5 and 5µg/cm^(2)(around ambient concentrations)of PM_(2.5)disrupted OEC membrane integrity and produced oxidative stress with elevated indicators of malondialdehyde(MDA)and reactive oxygen species(ROS).In transcriptomic sequencing,the terms concerning inflammatory cytokines and second messenger cyclic adenosine-3′,5′-monophoshate(cAMP)were enriched in two treatments.The cytokine array showed the levels of some cytokines were altered,although inflammatory responses may not remarkably occur.Meanwhile,PM_(2.5)disturbed cAMP contents and key genes in the cAMP signaling pathway.The effects of PM_(2.5)of both regions were largely consistent,while Wangdu samples caused more ROS and Dianshan Lake samples tended to induce inflammatory injury.Thus,with the application of a novel ALI-based in vitro OEC model,our study demonstrated that ambient PM_(2.5)has the ability to threaten the physiologies and functions of the olfactory system.