ROS/Caspase-3/GSDME Pathway Mediated Pyroptosis Plays A Role In Cyclophosphamide Induced Interstitial Cystitis In Mice

Objective: Interstitial cystitis(IC)is a chronic idiopathic inflammation with unknown etiology and etiology.About 90% of patients are female.Its main symptoms are frequent urination,urgent urination,and recurrent vesical-related pain,it is difficult to achieve satisfactory treatment results,to the quality of life of patients has brought serious impact.Therefore,exploring the pathogenesis and treatment of IC has become an urgent problem to be solved.Methods: The animal model of IC was established by injecting cyclophosphamide into C57BL/6J female mice.The bladder injury was evaluated by HE staining,edema and bleeding score.Western Blot and immunofluorescence revealed the expression of Caspase-3/GSDME in the tissues.Human uroepithelial cells(SV-HUC-1)were treated with acrolein,a metabolite of cyclophosphamide,and Caspase-3/GSDME activation levels were detected by Western Blot.The level of pyroptosis induced by acrolein was detected by LDH release assay,and PE/7-ADD staining by flow cytometry.Addition of acrolein after knockdown of Caspase-3/GSDME in SV-HUC-1 and detection of altered levels of pyroptosis by Western Blot,LDH,flow cytometry and morphological assays.In addition,the pro-death of cells induced by acrolein and reactive oxygen species(ROS)were detected by adding ROS inhibitors.Finally,Caspase-3 inhibitor(Z-DEVD)was injected into IC mice,and bladder injury and cell scorch death were detected by HE staining and Western Blot.Results: Bladder injury and Caspase-3/GSDME were activated in IC mice induced by cyclophosphamide,and Caspase-3/GSDME/IL-1β activation and pyroptosis were also observed in cell models in vitro.In addition,we found that acrolein mediated pyroptosis of uroepithelial cells through the ROS/Caspase-3/GSDME pathway.After treatment with a Caspase-3 inhibitor,the bladder edema and bleeding scores of IC mice were decreased,and the expression of Caspase-3/GSDME was relatively decreased.Conclusions: Cyclophosphamide induces bladder injury in IC mice through ROS/Caspase-3/GSDME pathway,and it may be due to the pyroptosis of uroepithelial cells.Caspase-3 inhibitors attenuated cyclophosphamide-induced bladder injury and Caspase-3/GSDME activation in mice.