**2. Results**

#### *2.1. Effect of AST on Prostate Weight*

T was used to induce prostatic hyperplasia in rats for four weeks, and the prostate (including ventral and dorsal prostate) weight of each rat was measured. As shown in Figure 2A,C, as compared with the BPH model control rats, the prostate and ventral prostate weights of the AST-treated rats decreased in a dose-response manner, while the prostate weights (*p* < 0.05) and ventral prostate weights (*p* < 0.01) of the 80 mg/kg AST-treated rats significantly declined. Prostate weights and ventral prostate weights of EPR-treated rats were also lower than those of the BPH model control rats. Dorsal prostate weights were not significantly different between the treated groups and the BPH model control group, as shown in Figure 2E.

#### *2.2. Effect of AST on the Body Weight and Prostate Index*

The body weights of rats treated with AST or epristeride (EPR) for four weeks are shown in Figure 2G. The prostate index was defined as the ratio of prostate weight to the rat's body weight. The same effects shown in the prostate weights and ventral prostate weights were also found in the prostate index and ventral prostate index values in the AST-treated and EPR-treated rats (Figure 2B,D). The dorsal prostate index values in the treated groups and the BPH model control group did not differ significantly, as shown in Figure 2F.

**Figure 2.** Rat body weights (**G**) and the effect of AST on the weight of the prostate and the prostate index (including ventral and dorsal prostate). Data represent the mean ± SEM (*n* = 12). \* Significantly different from BPH model control group, *p* < 0.05 and \*\* significantly different from BPH model control group, *p* < 0.01. (**A**) Prostate weight; (**B**) prostate index; (**C**) ventral prostate weight; (**D**) ventral prostate index; (**E**) dorsal prostate weight; (**F**) dorsal prostate index.

#### *2.3. Effect of AST on the Histopathology and Ultrastructural Pathology of Prostate Tissues*

A histopathological examination, called the "golden standard," is one of the most important and reliable diagnostic methods for the evaluation of pathogenesis. The effect of AST on the histomorphology of ventral prostates in BPH model rats is shown in Figure 3A–F. The histological features found in the BPH model control rats were tall columnar epithelium, simple multifocal epithelial thickening with cellular crowding, and folding of the lining epithelium extending into lumina (Figure 3B). As compared with the BPH model control rats, these features were gradually ameliorated in the AST-treated rats (Figure 3C–E) in a dose-dependent manner, while similar morphological changes were observed in the EPR-treated rats (Figure 3F).

The epithelial thicknesses of ventral prostates in all rats were measured, and the average values of epithelial thickness in all groups are shown in Figure 3G. The average values of epithelial thickness in the AST-treated rats were significantly lower (*p* < 0.01) than in the BPH model control rats, shown in a dose-response manner; the average values of epithelial thickness in the EPR-treated rats also markedly decreased as compared with those in the BPH model control rats (*p* < 0.01).

Secretory granules in ventral prostates were observed using transmission electron microscopy (TEM), as shown in Figure 4. As compared with the BPH model control rats, there were fewer secretory granules observed in the AST-treated rats in a dose-dependent manner.

**Figure 3.** *Cont*.

**Figure 3.** Effect of AST on histomorphology and epithelial thicknesses of ventral prostates in BPH rats. (**A**) No abnormal histological changes were observed in the sham operation; tall columnar epithelium, simple multifocal epithelial thickening with cellular crowding, and folding of the lining epithelium extending into lumina (arrows) were observed in: (**B**) the BPH model control rats; (**C**) 20 mg/kg, (**D**) 40 mg/kg, and (**E**) 80 mg/kg AST-treated BPH rats; (**F**) EPR-treated BPH rats; Hematoxylin and eosin (H&E) 100×; (**G**) epithelial thicknesses of prostates in the sham operation, BPH model control group, and AST or EPR treated groups. Data represent the mean ± SEM. (*n* = 12). \*\* Significantly different from BPH model control group, *p* < 0.01.

**Figure 4.** *Cont*.

**Figure 4.** Images of ventral prostates under TEM, 4200×. Secretory granules (arrows) were observed in: (**A**) Sham operation; (**B**) BPH model control rats; (**C**) 20 mg/kg, (**D**) 40 mg/kg, and (**E**) 80 mg/kg AST-treated BPH rats; (**F**) EPR-treated BPH rats.

#### *2.4. Effect of AST on the Superoxide Dismutase (SOD) Activity of Prostates*

SOD is an important antioxidant enzyme in organisms. The effect of AST on the SOD activity of ventral prostates in the BPH model rats is shown in Figure 5. As compared with the BPH model control rats, the SOD activity of prostates in the AST-treated rats increased in a dose-dependent manner, while the SOD activity of prostates in the 40 mg/kg (*p* < 0.05) and 80 mg/kg (*p* < 0.01) AST-treated rats increased significantly.

**Figure 5.** AST increased the SOD activity of ventral prostates. Data represent the mean ± SEM. (*n* = 5). \* Significantly different from BPH model control group, *p* < 0.05, and \*\* significantly different from BPH model control group, *p* < 0.01.

#### *2.5. Effect of AST on the Levels of T and DHT*

T and DHT are the primary androgens in the prostate. The levels of T and DHT in ventral prostates in all groups are shown in Figure 6A,B. As compared with the BPH model control rats, the prostate T and DHT levels in the AST-treated rats decreased, while the T levels in the 40 mg/kg and 80 mg/kg AST-treated rats significantly decreased (*p* < 0.05); the DHT levels of prostates in the 40 mg/kg AST-treated rats (*p* < 0.05) also decreased significantly.

**Figure 6.** AST decreased levels of T (**A**) and DHT (**B**) in ventral prostates. Data represent the mean ± SEM. (*n* = 5). \* Significantly different from BPH model control group, *p* < 0.05, and \*\* significantly different from BPH model control group, *p* < 0.01.
