Effects of genistein on male sprague dawley rats reproductive development

Genistein (Gen), is commonly consumed phytoestrogen among Asian and known to exert weak estrogenic effects. To account for potential reproductive effects in male rats, Control, Gen1, Gen10, Gen100 mg/kg body weight and Estradiol were administered to gestational day 10 (GD10) female Sprague Dawley for 5 weeks. At postnatal day, P50, the rats were sacrificed. Blood was taken and reproductive tissues were processed. At birth, body weight (BW) and anogenital distance (AGD) in Gen10 and Gen100 decreased significantly from Control. Throughout experiment, BW and AGD of Gen10 decreased significantly. Preputial separation (PPS) was significantly longer in Gen100 and one rat from Gen10 exhibited unilateral testis descent at P50. Testicular weight and serum testosterone level were reduced in a dose-dependent manner. Histopathological analysis of the seminiferous tubules in Gen1 group is comparable to the Control group. However, the seminiferous tubules of the Gen10 and Gen100 groups showed evidence of overstimulated spermatogenesis. From the immunohistochemical (IHC) analysis, there was higher staining intensity indicating increased expression of 3β-hydroxysteroid dehydrogenase (3β-HSD) and Connexin43 (Cx43) in Gen10 and Gen100 groups compared to Control. Thus, administration of genistein during the critical period of early development could cause antiestrogenic or/and estrogenic influence on the development and functions of the male reproductive system.