The histopathological effects of intracavernosal mitomycin-C injection in a rat Peyronie's disease model

Abstract

Introduction: We aimed to evaluate whether or not mitomycin-C (MMC) has an antifibrotic effect on transforming growth factor-beta (TGF-β)-induced Peyronie's disease (PD) in a rat model. Methods: Eighteen 12-week-old male Sprague-Dawley rats were divided into three groups: Group 1=TGF-β1 (n=7); Group 2=TGF-β1+MMC (n=7); and Group 3=Sham group (0.25 ml bovine serum albumin injected) (n=4). All groups were sacrificed on the sixth week of the procedure and their penises were excised. All penis specimens were evaluated semi-quantitatively and quantitatively with histochemical, immunohistochemistry, and image analysis. Results: Both Group 1 and Group 2 had significantly higher fibrosis scores and lower elastic fibers in both outer surface of tunica albuginea (TA) and subsinusoidal area compared with Group 3. When compared with Group 1, the amount of collagen was significantly decreased in Group 2. Intracavernosal MMC injection (Group 2) ended up with lower elastic fibers when compared with Group 1. According to the quantitative analyses, when compared with Groups 1 and 3, lower dorsal, ventral, and trabecular thickening values were seen in Group 2. These parameters were only statistically significant when compared with Group 1, suggesting the antifibrotic effect of TGF-β1-induced fibrosis. Both Groups 1 and 2 showed lower decorin staining levels in subsinusoidal areas of tunica albuginea (SATA) and subsinusoidal areas of trabecular wall (SATW) when compared with Group 3. The statistically significant difference was only detected between Group 1 and Group 3. Conclusions: Our study demonstrates the antifibrotic effects of MMC on PD. Further clinical studies are necessary to make inferences regarding its clinical use.