Effect of partial bladder outlet obstruction on the rat urinarybladder and the possible role of curcumin on Aquaporin 1expression: a light and electron microscopic study

BackgroundAquaporins (AQPs) are membrane proteins that facilitate water movement acrossbiological membranes. Moreover, their expression has recently been reported to beinvolved in dysfunctions due to partial bladder outlet obstruction (PBOO). There isincreasing evidence that curcumin might have remarkable beneficial effects in variousdiseases.Aim of the workThe aim of the work was to investigate the effect of PBOO on the rat urinary bladderand AQP1 expression. The impact of curcumin on PBOO and AQP1 expression wasdetected as well.Material and methodsForty adult female rats were divided into four equal groups. Group I underwent asham operation and served as the control group. Group II underwent a PBOO.Group III underwent a PBOO and was then treated 1 day later with curcumin(150 mg/kg) administered orally daily for 14 days. Group IV underwent asham operation and 1 day later received curcumin as in group III. Histological,immunohistochemical, and morphometric studies were then conducted.ResultsSignificant increase in the area% of AQP1expression was detected in group IIcompared with groups I and III. Examination of group II showed disruption ofthe urothelium with multiple cyst formation. Semithin sections revealed multipleintraepithelial mast cells. Signs of widening of intercellular spaces were alsoobserved. Moreover, Mallory trichrome-stained sections revealed significant increasein the area% of collagen fibers in group II compared with groups I and III. Fortunately,curcumin was found to downregulate AQP1 expression and to ameliorate most of thehistological alterations observed after PBOO.ConclusionThis study showed that PBOO caused a significant increase in the expression ofAQP1. This might imply that AQP1 has a functional role in the detrusor instability thatoccurs in association with PBOO. Meanwhile, significant decrease in AQP1 inducedby curcumin helped to ameliorate most of the bladder histological alterations causedby PBOO.