CASP1 and chronic obstructive pulmonary disease: There is evidence that CSE induces pyroptosis via the ROS-NLRP3-caspase-1-GSDMD pathway in human bronchial epithelial cells.246 Particulate matter (PM2.5) also plays a role in lung injury: after PM exposure, Sirtuin1 (SIRT1) inhibits sterol regulatory element binding protein-1 (SREBP-1) and further decreases PIR and NLRP3 inflammasomes.247 In addition, the ROS-TRPM2-Ca2+-NLRP3 pathway also contributes to lung injury induced by PM 2.5.248 These studies indicate that the NLRP3 inflammasome can be activated via multiple pathways in lung injury, which provides a new therapeutic target for COPD.