In summary, we hypothesized that circMAPK1 facilitated KDM2B mRNA decay via recruiting UPF1, and the inhibition of KDM2B-mediated WNK1 demethylation further suppressed WNK1 expression, thus triggering NLRP3-mediated pyroptosis in sepsis-induced ALI. Here, KDM2B is linked to acute respiratory distress syndrome.