Long time exposure to soy/isoflavone-rich diet enhances testicular and prostate health in Long-Evans rats

• High vs. Low levels of isoflavone diets were compared in rats.
• Morphological analyses were performed on body weight and various reproductive tissues.
• High-isoflavone diets decreased prostate weight and white adipose tissue deposition.
• High-isoflavone diets increased testicular weight, Sertoli cell area and semniferous tubule volume.

Soy isoflavone consumption appears to be beneficial for several health parameters. We report the influence of (lifelong exposure to) a high soy/isoflavone (High-Iso) compared to a low soy/isoflavone (Low-Iso) diet on body weight (BW), white adipose tissue (WAT) deposition, prostate weight (PW), testicular weight (TW), and testosterone levels in young adult male Long-Evans rats. WAT deposition and the WAT/BW ratios were significantly less in High-Iso vs. the Low-Iso fed animals. TW and TW/BW ratios were significantly greater in High-Iso vs. Low-Iso fed animals. Sertoli cell area, seminiferous tubule lumens and seminiferous tubule areas were significantly greater in High-Iso vs. Low-Iso animals. These data suggest that consumption of a soy diet high in isoflavone/polyphenolic molecules from conception appear to be beneficial in decreasing PW and WAT deposition while increasing TW, Sertoli cell area and seminiferous tubule volume.