Portulaca oleracea Extract Ameliorates Testosterone Propionate-Induced Benign Prostatic Hyperplasia in Male Sprague-Dawley Rats

Abstract

Benign prostatic hyperplasia (BPH) is a distressing health problem that can cause serious complications in aging men. Androgens are implicated in the causation of BPH. Portulaca oleracea (PO) is a natural product with diverse pharmacological effects. The objective of this study was to investigate the effect of PO in a rat model of testosterone propionate (TP)-induced BPH and explore the underlying mechanisms. Thirty-five Sprague-Dawley (SD) rats were divided into the following equal groups (n = 7): normal control (NC) group, TP (3 mg/kg) group, finasteride (10 mg/kg) group, 25 and 50 mg/kg PO groups. At the end of the experiment, the body weights (BWs) of the rats were measured before they were euthanized to the establishment obtain serum and prostate weight (PW). TP-induced levels of androgen-related proteins in the prostate were also investigated. In the TP group, prostate size, BW, serum DHT level, prostate epithelial cell thickness and androgen-related protein level were higher than those in the NC group (p < 0.001). PO reversed TP-induced BPH in a dose-dependent manner (p < 0.01) and its effect was similar to that of finasteride. A similar effect of PO on the androgen-related protein level was also observed. We successfully established a TP-induced BPH rat model. This is the first study to demonstrate that inhibition of androgen-related proteins using PO can alleviate BPH.

Keywords: Portulaca oleracea; androgen‐related proteins; benign prostatic hyperplasia; testosterone propionate.

FIGURE 1

Effect of Portulaca oleracea on prostatic hypertrophy in TP‐induced BPH rat model. A testosterone propionate‐induced BPH model was established. (A) Experimental schedule showing that each experimental group was administered simultaneously. (B) Representative images showing changes in prostate tissue in each experimental group on Day 28 (Scale bar = 1 cm). NC, normal control; TP, testosterone propionate.

FIGURE 2

Effect of Portulaca oleracea on prostate weight of TP‐induced BPH rat model. Analysis of the changes in the prostate weight to body weight (PW/BW) ratio in the TP group, finasteride group, PO 25 and PO 50 mg/kg group. Data expressed as mean ± SD. Statistical significance assessed by One‐way ANOVA followed by post hoc Dunnett's test: ###p < 0.001 versus normal control group; **p < 0.01 versus TP group. NC, normal control; TP, testosterone propionate.

FIGURE 3

Effect of Portulaca oleracea on DTH levels in serum of TP‐induced BPH rat model. Results of ELISA showing serum DHT levels in TP‐induced BPH rats. Data expressed as mean ± SD. Statistical significance assessed by One‐way ANOVA followed by post hoc Dunnett's test: ###p < 0.001 versus normal control group; *p < 0.05 versus TP group. NC, normal control; TP, testosterone propionate.

FIGURE 4

Effect of Portulaca oleracea on histological changes in prostate tissue of TP‐induced BPH rat model. Representative photomicrographs of H&E‐stained prostate tissue (panel magnification × 100). Representative photos of AR and SRD5A2 stained sections examined under a light microscope (panel magnification × 100) (Scale bar = 100 µm). AR, androgen receptor; H&E, haematoxylin & eosin; NC, normal control; TP, testosterone propionate.

FIGURE 5

Effect of Portulaca oleracea on prostate epithelial thickness of TP‐induced BPH rat model. Measurement of prostate epithelial tissue thickness in a rat model of testosterone‐induced benign prostatic hyperplasia (BPH). Epithelial thickness of prostate tissue. Data expressed as mean ± SD. Between‐group difference assessed using Student t‐test: ###p < 0.001 versus normal control group; **p < 0.01, ***p < 0.001 versus TP group. NC, normal control; TP, testosterone propionate.

FIGURE 6

Effect of Portulaca oleracea on protein expression of AR and SRD5A2 in prostate tissue of TP‐induced BPH rats. (A) Western blots showing protein expression bands of AR and SRD5A2 in each experimental group; (B) Measurements using Image J software. Data expressed as mean ± SD. Between‐group difference assessed using Student t‐test: ###p < 0.001 versus normal control group; **p < 0.01, ***p < 0.001 versus TP group. AR, androgen receptor; NC, normal control; TP, testosterone propionate.