Corn silk extract improves benign prostatic hyperplasia in experimental rat model

So Ra Kim; Ae Wha Ha; Hyun Ji Choi; Sun Lim Kim; Hyeon Jung Kang; Myung Hwan Kim; Woo Kyoung Kim

doi:10.4162/nrp.2017.11.5.373

Corn silk extract improves benign prostatic hyperplasia in experimental rat model

Nutr Res Pract. 2017 Oct;11(5):373-380. doi: 10.4162/nrp.2017.11.5.373. Epub 2017 Sep 14.

Authors

So Ra Kim¹, Ae Wha Ha², Hyun Ji Choi¹, Sun Lim Kim³, Hyeon Jung Kang⁴, Myung Hwan Kim⁵, Woo Kyoung Kim¹

Affiliations

¹ Department of Food Science and Nutrition, Dankook University, 119, Dandae-ro, Dongnam-gu, Cheonan-si, Chungnam 31116, Korea.
² Department of Food Science and Nutrition, Natural Nutraceuticals Industrization Research Center, DanKook University, Chungnam 31116, Korea.
³ Crop Foundation Division National Institute of Crop Science, RDA, Jeonbuk 55365, Korea.
⁴ Crop Post-harvest Technology Division, National Institute of Crop Science, RDA, Suwon, Gyeonggi 16613, Korea.
⁵ Department of Food Engineering, Dankook University, Chungnam 31116, Korea.

Abstract

Background/objectives: This study was conducted to investigate the effect of a corn silk extract on improving benign prostatic hyperplasia (BPH).

Materials/methods: The experimental animals, 6-week-old male Wistar rats, were divided into sham-operated control (Sham) and experimental groups. The experimental group, which underwent orchiectomy and received subcutaneous injection of 10 mg/kg of testosterone propionate to induce BPH, was divided into a Testo Only group that received only testosterone, a Testo+Fina group that received testosterone and 5 mg/kg finasteride, a Testo+CSE10 group that received testosterone and 10 mg/kg of corn silk extract, and a Testo+CSE100 group that received testosterone and 100 mg/kg of corn silk extract. Prostate weight and concentrations of dihydrotestosterone (DHT), 5α-reductase 2 (5α-R2), and prostate specific antigen (PSA) in serum or prostate tissue were determined. The mRNA expressions of 5α-R2 and proliferating cell nuclear antigen (PCNA) in prostate tissue were also measured.

Results: Compared to the Sham group, prostate weight was significantly higher in the Testo Only group and decreased significantly in the Testo+Fina, Testo+CSE10, and Testo+CSE100 groups (P < 0.05), results that were consistent with those for serum DHT concentrations. The concentrations of 5α-R2 in serum and prostate as well as the mRNA expression of 5α-R2 in prostate were significantly lower in the Testo+Fina, Testo+CSE10, and Testo+CSE100 groups than that in the Testo Only group (P < 0.05). Similarly, the concentrations of PSA in serum and prostate were significantly lower in the Testo+Fina, Testo+CSE10, and Testo+CSE100 groups (P < 0.05) than in the Testo Only group. The mRNA expression of PCNA in prostate dose-independently decreased in the Testo+CSE-treated groups (P < 0.05).

Conclusions: BPH was induced through injection of testosterone, and corn silk extract treatment improved BPH symptoms by inhibiting the mRNA expression of 5α-R2 and decreasing the amount of 5α-R2, DHT, and PSA in serum and prostate tissue.

Keywords: Prostate; Zea mays; finasteride; maysin; testosterone.