Sildenafil and febuxostat protect against doxorubicin-induced nephrotoxicity; however the exact mechanism remains to be elucidated. The effect of sildenafil and febuxostat on doxorubicin-induced nephrotoxicity in rats was studied. Male rats were subdivided into nine groups. The 1st group served as normal control, the 2nd group received dimethylsulfoxide 50% (DMSO), the 3rd group received doxorubicin (3.5 mg/kg, i.p.), twice weekly for 3 weeks. The next 3 groups received sildenafil (5 mg/kg; p.o.), febuxostat (10 mg/kg; p.o.) and their combination, respectively daily for 21 days. The last 3 groups received doxorubicin in combination with sildenafil, febuxostat or their combination. Nephrotoxicity was evaluated histopathologically by light microscopy and biochemically through measuring the following parameters, Kidney function biomarkers [serum levels of urea, creatinine and uric acid], oxidative stress biomarkers [kidney contents of glutathione reduced (GSH) and malondialdehyde (MDA)], The apoptotic marker namely; caspase-3 in kidney tissue and the inflammatory mediator tumor necrosis factor alpha (TNF-α). doxorubicin-induced a significant elevation in nephrotoxicity markers, expression of caspase-3 and caused induction of inflammation and oxidative stress. Histological changes in the kidney was tubular necrosis.
Sildenafil and/or febuxostat administration with doxorubicin caused a significant decrease in nephrotoxicity markers and inflammatory mediators, restoration of normal values of oxidative stress biomarkers and hampering the expression of renal caspase-3. They also ameliorate histological changes induced by doxorubicin. sildenafil and febuxostat are promising protective agents against doxorubicin-nephrotoxicity through improving biochemical, inflammatory, histopathological and immunohistochemical alterations induced by doxorubicin.