Role of non-coding RNA hsa_circ_0001495 in 16HBE cellular inflammation induced by PM2.5 and O3 combined exposure

Background PM2.5 and O3 are the main air pollutants in China, and inflammation of the respiratory system is one of their main toxic effects. Cyclic RNAs are involved in many pathophysiological processes, but their relationship to the combined exposure to PM2.5 and O3 has not yet been investigated. Objective To elucidate the biological function played by hsa\_circ\_0001495 in the induction of 16HBE cellular inflammation by combined exposure to PM2.5 and O3. Method Detection of cell survival after 24h exposure of 16HBE cells to a combination of PM2.5 and O3 by CCK8. RT-qPCR and ELISA were used to detect inflammatory factors in 16HBE cells after co-exposing to PM2.5 and O3. CircRNA was screened using high throughput sequencing and bioinformatics analysis approaches. RNaseR experiments were carried out to verify the circular RNA properties of the circRNAs. Cytoplasmic-nuclear subcellular localisation assays and fish assays were used to verify the distribution of circRNAs in the nucleus versus the cytoplasm of the cell. To validate functions related with circRNA,RT-qPCR and ELISA were employed. Result Combined exposure to PM2.5 and O3 resulted in decreased cell viability.Combined exposure to PM2.5 and O3 resulted in 16HBE inflammation. High throughput sequencing and RT-qPCR results showed that the expression of hsa\_circ\_0001495 was significantly downregulated in 16HBE exposed to PM2.5 and O3 in combination. Hsa\_circ\_0001495 is not easily digested by RNaseR enzymes and has the properties of a circular RNA. Hsa\_circ\_0001495 is expressed in the cytoplasm as well as in the nucleus, but its distribution is predominantly in the cytoplasm. Conclusion In 16HBE cells, combined exposure to PM2.5 and O3 can induce an inflammatory response.hsa\_circ\_0001495 plays an inhibitory role in the inflammatory response of 16HBE cells that can be induced by combined exposure to PM2.5 and O3. ### Competing Interest Statement We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted.