Regulating ferroptosis by roflumilast attenuates cisplatin-induced kidney injury

Acute kidney injury (AKI) represents a concerning health challenge that alters renal structure and function. Ferroptosis has been identified as a cell death mechanism involved in AKI. Cisplatin is a widely used antineoplastic agent, but AKI is a serious limitation to its clinical use. We explored the effect of roflumilast on cisplatin-induced AKI. Wistar rats were divided into 3 groups (n = 7 per group); control group, cisplatin group rats received a single injection (7 mg/kg, i.p.), and roflumilast/cisplatin group: roflumilast was given two days earlier and one hour before cisplatin injection and was continued for the following five days. Kidney histological structure and renal function were assessed. Additionally, the effect on the antioxidant reduced glutathione (GSH) and malonaldehyde (MDA), the lipid peroxidation product, were investigated. Ferroptosis regulators such as xCT subunit of system Xc^-, ferritin and nuclear factor erythroid 2-related factor 2 (Nrf2) were assessed in renal tissue by ELISA whereas glutathione peroxidase 4 (GPX4) was assessed by both ELISA and immunohistochemistry. Histopathological evaluation showed that roflumilast ameliorated the renal structure and biochemical assessment of serum creatinine and blood urea nitrogen showed improvement in renal function. Roflumilast lowered renal MDA levels and elevated renal GSH levels demonstrating its antioxidant activity. Renal expression of GPX4 and xCT subunit of system Xc^- were elevated by roflumilast. Moreover, renal levels of ferritin and Nrf2 were increased. These results propose that roflumilast exerted a renoprotective effect by alleviating oxidative stress and inhibiting ferroptosis suggesting a new repurposed role for roflumilast.