Objective:

2

To investigate the effect and mechanism of Shuangshi Tonglin Capsules (SSTL) in the treatment of prostate fibrosis (PF).

Methods:

2

Human prostate stromal cells (WPMY-1) were used for

in vitro

experiments to establish PF cell models induced with estradiol (E

2

). The cell proliferation

migration and clonogenic capacity were determined by cell

counting kit-8

scratch assay

and crystal violet staining

respectively. Sprague-Dawley rats were used for

in vivo

experiments. The changes in histomorphology and organ index of rat prostate by SSTL were determined. Pathologic changes and collagen deposition changes in rat prostate were observed by haematoxylin and eosin (HE) and Masson staining. Enzyme-linked immunosorbent assay kits were used to determine changes in rat PF markers fibroblast growth factor-23 (FGF-23)

E

2

and prostate specific antigen (PSA). Mechanistically

changes in oxidative stress indicators by SSTL were determined in WPMY-1 cells and PF rats. Then the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) and transforming growth factor-β1 (TGF-β1)/Smad pathway-related proteins as well as Nrf2 and TGF-β1 mRNA were further detected by Western blot or quantitative real-time polymerase chain reaction both

in vivo

and

in vitro

.

Results:

2

In the efficacy study

SSTL significantly reduced the proliferation

migration

and clonogenic ability of cells

improved the morphology of the glandular tissue

significantly reduced the prostate index

reduced glandular fibrous tissue and collagen deposition

and resulted in a significant decrease in the levels of FGF-23

E

2

and PSA (

P

<

0.01 or

P

<

0.05). In the mechanistic study

SSTL ameliorated oxidative stress by significantly increasing superoxide dismutase and glutathione peroxidase levels and decreasing malondialdehyde level in WPMY-1 cells and rats (

P

<

0.01 or

P

<

0.05). SSTL significantly elevated the expressions of Nrf2

HO-1

NAD(P)H quinone oxidoreductase 1 (NQO-1)

and Smad7 proteins in both cells and rats

and significantly decreased the expressions of TGF-β1

collagen Ⅰ

α-smooth muscle actin and Smad4 proteins (

P

<

0.01 or

P

<

0.05). SSTL also elev

ated the content of Nrf2 mRNA and decreased the content of TGF-β1 mRNA in cells and rats (

P

<

0.01 or

P

<

0.05). The Nrf2 inhibitor ML385 was added in

in vitro

experiments to further validate the pathway relevance.

Conclusion:

2

SSTL was effective in improving PF

in vivo

and

in vitro

and its mechanism of action may function through the Nrf2/TGF-β1 signaling pathway.