Introduction: Elevated plasma homocysteine (Hcy) levels have been associated with several tissue injuries including heart and liver fibrosis. In these diseases, hyperhomocysteinemia (Hhcy) plays a major role in modulating the alteration of the balance between matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMPs), leading to the pathological accumulation of extracellular matrix (ECM) proteins. Since the effect of Hhcy on ECM of seminal vesicle was not studied, the aim of our research was to check if Hcy can induce a remodeling within seminal vesicles ECM.
Material and methods: The study was conducted in 22 adult male Wistar rats. The rats were divided into two groups: a control group, which received standard diet and tap water; the treated group received the same diet and water supplemented with solution of L-methionine (200 mg/kg b.w./day) for 6 months. Plasma homocysteine concentration was measured. Histological changes were observed with light microscope. The presence of collagen I and III and metalloproteinases (2, 3, 7 and 9) in the seminal vesicles was examined using immunohistochemistry and Western blotting.
Results: Plasma Hcy levels increased significantly after methionine treatment and interfered significantly with body weight in treated rats. The content of fibrillar collagens (I and III) in the wall of seminal vesicles was elevated in hyperhomocysteinemic rats. Moreover, we found that hyperhomocysteinemia increased the expression of MMP-2, -3, -7 and -9 in seminal vesicles of experimental rats.
Conclusions: Increased plasma concentration of Hcy accompanied by the accumulation of collagen and upregulation of MMPs in rat seminal vesicles might contribute to the remodeling of seminal vesicles.
Keywords: IHC; Western blot; collagen I; collagen III; hyperhomocysteinemia; metalloproteinases; rat; seminal vesicles.