PM_2.5 induced lung injury through upregulating ROS-dependent NLRP3 Inflammasome-Mediated Pyroptosis

The main cause of air pollution is PM_2.5, which directly causes lung injury through respiration. Oxidative stress and inflammation are considered to be the key mechanism of cell damage. Pyroptosis is a process of the programmed death of inflammatory cells and as a dangerous endogenous signal, it is widely involved in different inflammatory diseases. However, few studies have been conducted on PM_2.5 exposure and cell pyroptosis. In this study, we aimed to investigate the effect of PM_2.5 on apoptosis, pyroptosis and cell cycle arrest regulated by reactive oxygen species production. Balb/c mice were exposed to PM_2.5 dynamically and verified by the RAW264.7 cells in vitro. The results showed the activation of NF-κB and NLRP3 inflammasome and the release of IL-1β and reactive oxygen species were caused by exposure to PM_2.5. The maturation of IL-1β relied on Caspase-1, and the active Caspase-1 was related to cell pyroptosis. Oxidative stress, inflammation, apoptosis and pyroptosis all affected the cell cycle. This study describes a potentially important mechanism of PM_2.5-induced lung damage that PM_2.5 promotes lung injury via upregulating ROS-NLRP3-mediated the RAW264.7 cells pyroptosis.