Effect of Benincasa hispida fruits on testosterone-induced prostatic hypertrophy in albino rats

Benincasa hispida Cogn. has been used traditionally in India for the management of urinary disorders. The fruit of B hispida is used as a diuretic and the seeds have been reported to possess antiangiogenic effects in prostate cells.

The aim of the present study was to examine the effect of petroleum ether extract, ethanolic extract, and B hispida seed oil on hyperplasia of the prostate induced by the subcutaneous administration of testosterone in rats.

In vitro studies were performed to determine the 5α-reductase inhibitory potential of the extracts. The results of those studies paved the way for the pharmacologic screening of the extracts to assess their potential against testosterone-induced hyperplasia in rats. Nine groups containing 10 rats per group were created for this study. Hyperplasia was induced by administration of testosterone (3 mg/kg SC) for 14 days in all the groups except the vehicle-treated group. Simultaneous administration of petroleum ether extract (100 or 200 mg/kg PO), ethanolic extract (100 or 200 mg/kg PO), and B hispida seed oil (20 or 40 mg/kg PO) was conducted. A standard 5α-reductase inhibitor (ie, finasteride) was used as a positive control. The weight of the rats was recorded on day 0 (ie, day 1 of the study) and on day 14, and the influence of testosterone and test extracts on the weight of the rats was determined. On day 14, rats were euthanized; prostates were dissected out, and weighed. The rats' prostate/body weight (P/BW) ratio was then determined. Histologic examinations were performed on prostates from each group.

The petroleum ether extract as well as B hispida seed oil exhibited inhibition of 5α-reductase activity in in vitro studies. Ethanolic extract did not exhibit significant inhibitory potential in vitro. Further in vivo study found that testosterone treatment significantly increased the rats' P/BW ratio in all the groups except the vehicle-treated rats, and this increase in weight was significantly inhibited in rats administered petroleum ether extract (100 and 200 mg/kg PO) and B hispida seed oil (20 and 40 mg/kg PO). Ethanolic extract did not exhibit any significant activity.

Petroleum ether extract and B hispida seed oil inhibited testosterone-induced hyperplasia of the prostate in these rats. Further studies are needed to evaluate its effect in humans with benign prostatic hyperplasia.