Effects of Guizhi and Erxian Decoction on menopausal hot flashes: insights from the gut microbiome and metabolic profiles.

AIMS: To examine the influence of GED on the gut microbiota and metabolites using a bilateral ovariectomized (OVX) rat model. We tried to elucidate the underlying mechanisms of GED in the treatment of menopausal hot flashes. METHODS AND RESULTS: 16S rRNA sequencing, metabonomics, molecular biological analysis, and fecal microbiota transplantation (FMT) were conducted to elucidate the mechanisms by which GED regulates the gut microbiota. GED significantly reduced OVX-induced hot flashes and improved disturbances in the gut microbiota metabolites. Moreover, FMT validated that the gut microbiota can trigger hot flashes, while GED can alleviate hot flash symptoms by modulating the composition of the gut microbiota. Specifically, GED upregulated the abundance of Blautia, thereby increasing l(+)-ornithine levels for the treatment of menopausal hot flashes. Additionally, GED affected endothelial nitric oxide synthase and heat shock protein 70 (HSP70) levels in the hypothalamic preoptic area by changing the gut microbiota composition. CONCLUSIONS: Our study illuminated the underlying mechanisms by which GED attenuated the hot flashes through modulation of the gut microbiota and explored the regulatory role of the gut microbiota on HSP70 expression in the preoptic anterior hypothalamus, thereby establishing a foundation for further exploration of the role of the gut-brain axis in hot flashes.

The relationship between menopausal syndrome and gut microbes.

BACKGROUND: Gut microbes were closely related to women's health. Previous studies reported that the gut microbes of premenopausal women were different from those of postmenopausal women. However, little was known about the relationship between gut microbiota dysbiosis and menopausal syndrome (MPS). The aim of this study was to explore the relationship between MPS and gut microbes. METHODS: Patients with MPS (P group, n = 77) and healthy women (H group, n = 24) at menopause were recruited in this study. The stool specimen and clinical parameters (demographic data, follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), et al) of participants' were collected. We evaluated the differences in gut microbes by 16S ribosomal RNA gene sequencing. We used LEfSe to identify gut microbes with varying abundances in different groups. The Spearman correlation coefficients of clinical parameters and gut microbes were calculated. PICRUSt was used to predict the potential KEGG Ortholog functional profiles of microbial communities. RESULTS: The abundance of 14 species differed substantially between the MPS and menopausal healthy women (LDA significance threshold > 2.0) according to LEfSe analysis. Using Spearman's correlation analysis, it was discovered that E2 had a positive correlation with Aggregatibacter segnis, Bifidobacterium animalis, Acinetobacter guillouiae (p < 0.05, these three species were enriched in menopausal healthy women), while FSH and LH had a negative correlation with them (p < 0.05). KEGG level3 metabolic pathways relevant to cardiovascular disease and carbohydrate metabolism were enriched in the MPS (p < 0.05), according to functional prediction by PICRUST and analyzed by Dunn test. CONCLUSION: There was gut microbiota dysbiosis in MPS, which is reflected in the deficiency of the abundance of Aggregatibacter segnis, Bifidobacterium animalis and Acinetobacter guillouiae related to the level of sex hormones. In MPS individuals, species with altered abundances and unique functional pathways were found.