Uroprotective mechanism of quercetin against cyclophosphamide-induced urotoxicity: Effect on oxidative stress and inflammatory markers.

The urotoxicity is a common complication associated with patients receiving cyclophosphamide (CYP). This study was designed to investigate the uroprotective mechanism of quercetin (Quer) flavonoid against CYP induced urotoxicity via determination of oxidative stress markers as well as inflammatory mediators in bladder tissue. Forty male Wistar rats were divided into four groups; Normal group: received saline for 10 days. Quer control group: received quercetin 50 mg/kg/day for 10 days. CYP group: received saline for 10 days and injected with a single dose of 150 mg/kg CYP intraperitoneal (i.p) at day 8. The Quer + CYP group: received Quer 50 mg/kg/day for 10 days plus CYP 150 mg/kg i.p. injection at day 8. The CYP injection produced a significant elevation in bladder contents of malondialdehyde (MDA), and nitric oxide (NO), and bladder protein levels and expressions of tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) in addition to the upregulation of cyclooxygenase-2 (COX-2) bladder gene expression. Also, CYP injection showed a marked reduction in bladder levels of catalase, superoxide dismutase (SOD), and IL-10 when compared with normal group. Moreover, histopathological examination of the bladder showed degenerative alterations, severe edema, and inflammation following CYP injection. Quer attenuated the biochemical markers and histopathological changes induced by CYP. The uroprotective effect of Quer was exerted by restoring the balance between oxidative/antioxidative status and pro-/anti-inflammatory cytokines via its antioxidant and anti-inflammatory activities.