effect of partial bladder outlet obstruction on the rat urinary bladder and the possible role of curcumin on aquaporin 1expression: a light and electron microscopic study

Abstract

© 2014 The Egyptian Journal of Histology. BACKGROUND: Aquaporins (AQPs) are membrane proteins that facilitate water movement across biological membranes. Moreover, their expression has recently been reported to be involved in dysfunctions due to partial bladder outlet obstruction (PBOO). There is increasing evidence that curcumin might have remarkable beneficial effects in various diseases. AIM OF THE WORK: The aim of the work was to investigate the effect of PBOO on the rat urinary bladder and AQP1 expression. The impact of curcumin on PBOO and AQP1 expression was detected as well. MATERIAL AND METHODS: Forty adult female rats were divided into four equal groups. Group I underwent a sham 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 a sham operation and 1 day later received curcumin as in group III. Histological, immunohistochemical, and morphometric studies were then conducted. RESULTS: Significant increase in the area% of AQP1expression was detected in group II compared with groups I and III. Examination of group II showed disruption of the urothelium with multiple cyst formation. Semithin sections revealed multiple intraepithelial mast cells. Signs of widening of intercellular spaces were also observed. Moreover, Mallory trichrome-stained sections revealed significant increase in 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 the histological alterations observed after PBOO. CONCLUSION: This study showed that PBOO caused a significant increase in the expression of AQP1. This might imply that AQP1 has a functional role in the detrusor instability that occurs in association with PBOO. Meanwhile, significant decrease in AQP1 induced by curcumin helped to ameliorate most of the bladder histological alterations caused by PBOO.