Background:
Gold nanoparticles (AuNps) are promising agents for
prostate cancer therapy. Herein, the in vivo effects of 20 and 50 nm sized AuNps on experimentally induced
benign prostatic hyperplasia (BPH) was examined. Materials and methods: Adult male rats were divided into four groups (n=6-8 each). A negative control group and three groups were injected daily with
testosterone (3 mg/kg/subcutaneously) to induce BPH. Animals receiving
testosterone were randomized to untreated BPH group and two BPH groups which were treated intraperitoneally with 20 and 50 nm AuNps (5 mg/kg/daily) in addition to
testosterone. After three weeks, histopathological changes and serum levels of
testosterone and
dihydrotestosterone (DHT) were analyzed. In addition, the prostate tissue levels of transforming growth factor-β1 (TGF-β1),
vascular endothelial growth factor-a (
VEGF-A) and
interleukin-6 (IL-6) were measured using ELISA. Results: There were significant increases in the prostate
weight/body weight ratio, serum
testosterone and DHT and in the prostate tissue content of TGF-β1,
IL-6 and
VEGF-A in the untreated BPH group. histological examination showed morphological abnormalities with more proliferation in the glandular epithelial and stromal area and with abundant epithelial papillary folds in the BPH group. Simultaneous administration of 50 nm AuNps with
testosterone tended to increase the prostate
weight/body weight ratio and increase the tissue level of
IL-6 in compared to the BPH group. Conversely, treatment with 20 nm AuNps significantly reduced the elevated tissue content of TGF-β1,
IL-6, and
VEGF-A. Histopathological examination also showed that 20 nm but not the 50 nm AuNps administration ameliorates
testosterone-induced
prostatic hyperplasia. Conclusions: In experimentally induced BPH, AuNps can inhibit the progression of BPH in a size-dependent manner. while 20 nm AuNps ameliorate BPH by its inhibitory effects on the prostatic cell proliferation,
inflammation and angiogenesis, the 50 nm AuNps could potentially exacerbate the development of BPH in rats, mainly through enhancing the inflammatory process.