Figure 1.

In the canonical pathway of pyroptosis, NLRP3 recognizes stimulus (DAMPS/PAMPS) and binds to the ACS through PYD-PYD interaction and then occurs the formation of ASC focal points which triggers the recruitment of pro-caspase-1 to assemble into NLRP3 inflammasome. In the inflammasome, pro-caspase-1 is cleaved into the active forms, which catalyzes the cleavage of pro-IL-1β, pro-IL-18, and GSDMD. Mature GSDMD forms pores on cell membrane, leading to the outflow of cell contents such as IL-1β and IL-18, thus exhibiting an inflammatory response. It is noteworthy that the transcription of NLRP3 genes is regulated by the ROS/NF-κB signaling pathway. In the noncanonical pathway of pyroptosis, caspase-4/5/11 directly recognizes stimulus and gets activated, then causing cleaving GSDMD to promote pyroptosis.