Abstract
Hemorrhagic cystitis is a potentially deadly complication associated with radiation therapy and chemotherapy. This study explored the protective effect of edaravone (ED) on cyclophosphamide (CP)‐induced hemorrhagic cystitis, oxidative stress, and inflammation in rats. The animals received 20 mg/kg ED for 10 days and a single injection of 200 mg/kg CP on day 7. CP induced tissue injury manifested by the diffuse necrotic changes, disorganization of lining mucosa, focal hemorrhagic patches, mucosal/submucosal inflammatory cells infiltrates, and edema. CP increased malondialdehyde (MDA), nitric oxide (NO), tumor necrosis factor‐alpha, and interleukin 6 (IL‐6), decreased IL‐10, and upregulated toll‐like receptor 4 (TLR‐4), nuclear factor‐kappa B (NF‐κB) p65, Janus kinase 1 (JAK1), and signal transducer and activator of transcription 3 (STAT3) in the urinary bladder of rats. ED effectively prevented the histopathological alterations, decreased MDA, NO, and inflammatory mediators, and downregulated TLR‐4, NF‐κB, JAK1, and STAT3 in CP‐induced rats. Treatment with ED upregulated ikβ kinase β, IL‐10, nuclear factor‐erythroid 2 related factor 2 (Nrf2), and cytoglobin, and boosted glutathione, superoxide dismutase, and glutathione S‐transferase. Molecular docking simulations revealed the ability of ED to bind TLR‐4, NF‐κB, JAK1, and STAT3. In vitro, ED increased the cytotoxic activity of CP against HeLa, Caco‐2, and K562 cell lines. In conclusion, ED prevented CP‐induced hemorrhagic cystitis in rats by attenuating oxidative stress, suppressing TLR‐4/NF‐κB, and JAK1/STAT3 signaling and boosted Nrf2, cytoglobin, and antioxidants.