Efficiency of Chinese medicine Bushen Huatan formula for treatment of polycystic ovary syndrome in mice via regulating gut microbiota and PPARγ pathway.

Abstract

To explore the effect and mechanism of Chinese medicine Bushen Huatan formula in treatment of polycystic ovary syndrome (PCOS). Twenty-four SPF female C57BL/6J mice were randomly divided into 3 groups with 8 animals in each group. Control group was given drinking water ad libitum; PCOS was induced by giving letrozole gavage and high-fat diet in model group and treatment group; treatment group received Bushen Huatan formula suspension for 35 d. The sex hormone levels of mice were detected by enzyme-linked immunosorbent assay. Ovary morphology was observed under light microscope after hematoxylin and eosin staining. The feces in the colon of mice were collected, and the gut microbiota was detected by 16S rRNA sequencing. The short chain fatty acids were detected by gas chromatography-mas spectrometry. The expression of peroxisome proliferator activated receptor (PPARγ) was detected by immunohistochemistry. The mRNA expression of mucin-2, occludin-1, tight junction protein zonula occludens 1 (ZO-1) and PPARγ in intestinal epithelium were detected by realtime RT-PCR. The expression of inducible nitric oxide synthase (iNOS) and PPARγ was detected by Western blotting. Compared with the control group, the body weight, serum levels of follicle stimulating hormone, luteinizing hormone and testosterone in the model group were increased, and serum levels of estradiol were decreased (all P<0.01); the ovarian structure under light microscope was consistent with the characteristics of PCOS. Compared with the model group, the serum levels of sex hormone and ovarian structure in treatment group were improved. The overall structure of gut microbiota in PCOS model mice changed. Compared with control group, there were significantly reduced abundance of Firmicutes, and increased abundance of Verrucomicrobia, Proteobacteria and Actinobacteria inthe model group at phylum level (all P<0.05); there were significantly reduced abundance of Lactobacillus, and increased abundance of Akkermansia, Lachnoclostridium, Lactococcus and Eubacterium_coprostanoligenes at genus level (all P<0.05). The disordered condition of gut microbiota was significantly improved in treatment group. Compared with control group, the contents of acetic acid, propionic acid and butyric acid in feces of model group were significantly decreased (all P<0.05); while the contents of propionic acid and butyric acid in treatment group were significantly increased compared with model control group (both P<0.05). Compared with control group, the mRNA expression of ZO-1 and protein expression of iNOS in model group were significantly increased, and the protein expression of PPARγ and the mRNA expressions of mucin-2 and occludin-1 were significantly decreased (all P<0.05). Compared with model group, the mRNA expression of ZO-1 and protein expression of iNOS in treatment group were decreased, and the protein expression of PPARγ and the mRNA expressions of mucin-2 and occludin-1 were increased. PCOS induced by letrozole high-fat diet induces microflora imbalance in mice. Chinese medicine Bushen Huatan formula may increase the level of short chain fatty acid by regulating gut microbiota, thereby activating the intestinal PPARγ pathway and improving intestinal barrier function to act as a cure for PCOS.