Ferroptosis contributes to cyclophosphamide-induced hemorrhagic cystitis.

Cyclophosphamide (CYP) is extensively used in tumor therapy, but its clinical application is limited by its toxic effects on the bladder. Since CYP-induced cystitis is believed to be mediated by acrolein (ACR), a product of lipid peroxidation that triggers ferroptosis, we hypothesized that ferroptosis might be an essential molecular mechanism underlying CYP-induced cystitis. The purpose of this study was to test this hypothesis. Intraperitoneal injection of CYP led to bladder hemorrhage and edema, along with increased oxidation, inflammation, and cell injury. Further analysis revealed these changes were associated with altered ferroptosis markers in the bladder, such as FPN1, ACSL4, SLC7A11, and GPX4, indicating the existence of ferroptosis. Administration of ferroptosis inhibitor dexrazoxane (DXZ) improved ferroptosis and prevented CYP-induced pathological changes in the bladder. Collectively, our study revealed that ferroptosis is an important mechanism underlying CYP-induced cystitis, and therapeutic approaches targeting ferroptosis could be developed to treat CYP-induced cystitis.