Differential modulation of ferroptosis pathways by NOX1/4 and NLRP3 inhibition in DSS-induced colitis

Ferroptosis contributes to the pathogenesis of inflammatory bowel disease, but how NOX1/4 and NLRP3 pathways regulate this process remains unclear. This study aimed to investigate the therapeutic effects and mechanisms of the NOX1/4 inhibitor Setanaxib (SET) and the NLRP3 inhibitor Dapansutrile (DAP) in a mouse model of DSS-induced colitis. The DSS-induced colitis mouse model was established. SET and DAP were administered separately to evaluate their effects on disease activity, iron metabolism, ferroptosis indicators, and oxidative stress. Weight loss, colonic inflammation, and DAI scores in mice treated with DSS were alleviated by both SET and DAP, which also attenuated the suppression of colonic GPX4, SLC7A11, and FTH expression. Additionally, both compounds downregulated serum iron, colonic iron accumulation, and hepcidin levels in mice treated with DSS. Notably, SET significantly downregulated colonic TfR1 expression, ameliorated colonic oxidative stress (increased GSH and decreased ROS, GSSG, MDA, and 4-HNE), and inhibited colonic NLRP3 expression in mice treated with DSS, whereas DAP had no significant effect on TfR1, oxidative stress markers, or NOX1/4 expression. DSS-induced ulcerative colitis in mice was ameliorated by both SET and DAP, which also attenuated the DSS-induced suppression of GPX4/SLC7A11 expression and improved iron metabolism, suggesting that NOX1/4 and NLRP3 signaling participate in regulating iron metabolism and ferroptosis. Notably, SET exerted protective effects through dual inhibition of NOX1/4 and NLRP3 and antioxidant activity, whereas DAP regulated iron metabolism and ferroptosis via an oxidative stress-independent pathway, indicating that NLRP3 may regulate iron metabolism and ferroptosis through non-oxidative stress pathways, as well as the existence of the NOX1/4-NLRP3-iron metabolism/ferroptosis axis. These findings may inform precision treatment strategies for UC.