Pumpkin Seed Oil and Phytosterol-F Can Block Testosterone/Prazosin-Induced Prostate Growth in Rats

INTRODUCTION: This study was undertaken to investigate the effects of pumpkin seed oil alone or combined with Phytosterol-F on testosterone/prazosin-induced (T-P) prostate growth in rats. MATERIALS AND METHODS: Forty adult Wistar rats were divided into five groups, including: one control group, rats treated with vehicle only, one group treated with T-P, and two groups of T-P-treated rats, one receiving orally pumpkin seed oil alone and one group receiving orally pumpkin seed oil combined with Phytosterol-F. Two weeks later, the prostatic weight-to-body weight ratio was determined after sacrifice. The total protein concentration was measured by using a protein assay. Some ventral prostatic tissues were histologically examined after hematoxylin-eosin staining. RESULTS: Histological sections of the ventral prostate showed that the architecture of the prostate glands became hyperplastic in the T-P rats, but not in the control or vehicle-treated animals. As compared with the control or vehicle group, T-P rats had a significantly higher prostatic weight-to-body weight ratio for the ventral prostate (p=0.05 and p=0.007, respectively), but not for the dorsolateral prostate (p=0.53 and p=0.73, respectively). The T-P rats had significantly higher protein levels within both lobes (ventral lobe, p=0.02 and p<0.0001, respectively; dorsolateral lobe, p=0.06 and p=0.005, respectively). As compared with the T-P-alone rats, the TP rats treated with pumpkin seed oil alone or pumpkin seed oil combined with Phytosterol-F had a significantly lower weight ratio for the ventral prostate (p=0.01 and p=0.004, respectively) and significantly lower protein levels within both lobes (p=0.03 and p=0.003, respectively; p=0.007 and p=0.002, respectively). In addition, Phytosterol-F had some additive effect on the total protein synthesis within the ventral prostate (p=0.02). CONCLUSION: Pumpkin seed oil alone or combined with Phytosterol-F can block the T-P-induced increases in prostatic weight-to-body weight ratio and protein synthesis.