Low-level PM induces the occurrence of early pulmonary injury by regulating circ_0092363.

The significant correlation between particulate matter with aerodynamic diameters of ≤ 2.5 µm (PM) and the high morbidity and mortality of respiratory diseases has become the consensus of the research. Epidemiological studies have clearly pointed out that there is no safe concentration of PM, and mechanism studies have also shown that exposure to PM will first cause pulmonary inflammation. Therefore, the purpose of this study is to explore the mechanism of early lung injury induced by low-level PM from the perspective of epigenetics. Based on the previous results of population samples, combined with an in vitro/vivo exposure model of PM, it was found that low-level PM promoted the transport of circ_0092363 from intracellular to extracellular spaces. The decreased expression of intracellular circ_0092363 resulted in reduced absorption of miR-31-5p, leading to inhibition of Rho associated coiled-coil containing protein kinase 1 (ROCK1) and the subsequent abnormal expression of tight junction proteins such as Zonula occludens protein 1 (ZO-1) and Claudin-1, ultimately inducing the occurrence of early pulmonary injury. Furthermore, this study innovatively introduced organoid technology and conducted a preliminary exploration for a study of the relationship among environmental exposure genomics, epigenetics and disease genomics in organoids. The role of circ_0092363 in early pulmonary injury induced by low-level PM was elucidated, and its value as a potential diagnostic biomarker was confirmed.