Abstract:

The aim of this study is to observe the therapeutic effect of Inonotus Obliquus Polysaccharide (IOP) on chronic nonbacterial prostatitis (CNP) and its effect on the helper T cells (Th17) and regulatory T cells (Treg) immune imbalance. The CNP rat models established by injecting Xiaozhiling injection were randomly divided into the model group, cernilton (40 mg/kg, i.g.) group and low-dose (35 mg/kg, i.g.), medium-dose (70 mg/kg, i.g.) and high-dose (140 mg/kg, i.g.) groups, with the same volume of saline injected into the same site as the control group. The prostate’s wet weight and body mass served as the basis for calculating the prostate index. The serum level of prostate-specific antigen (PSA) was detected by ELISA and the histopathology of prostate tissue was detected by HE staining. The protein expression of Foxp3, ROR-γt and STAT3 in rat prostatic tissue was determined by Western blot. The levels of Th17 and Treg cells infiltrated into the spleen were measured by flow cytometry. The results showed that treatment with IOP significantly reduced the levels of prostate index and serum PSA, and attenuated the pathological injury of the prostate tissue induced by CNP. With respect to samples induced by CNP alone, IOP treatment repressed the increased mRNA levels of IL-6, IL-17, IL-21, IL-23, ROR-γt and STAT3 in prostate tissue, while increasing the mRNA levels of IL-10, TGF-β and Foxp3 in prostate tissue. Meanwhile, IOP treatment attenuated the upregulation of the protein expression levels of ROR-γt and STAT3 in prostate tissue. Additionally, the protein expression of Foxp3 in prostate tissue was increased in the IOP-treated group. Flow cytometry analysis further demonstrated that IOP treatment regulated the balance between Th17 and Treg cells in the spleen in rat with CNP. Our study is the first to elucidate that IOP has significant therapeutic effects on CNP through regulation of Th17/Treg balance. Collectively, the study provides evidence for the potential of IOP to treat CNP.

Key words: Inonotus obliquus polysaccharide, Chronic nonbacterial prostatitis, Th17, Treg, Th17/Treg balance