Background. Polycystic ovary syndrome (PCOS) is the most common endocrinopathy associated with infertility and metabolic disorders. The ethology and pathogenesis of PCOS are not fully understood. The role of gut microbiota (GM) disorders in the genesis of insulin resistance and in the development of PCOS is ambiguous.
Aims to compare the GM of patients with PCOS and healthy women, to evaluate the relationship of various groups of microorganisms with markers of chronic inflammation.
Methods. A single-center cross-sectional study was conducted involving 148 women: 118 with PCOS and 30 somatically healthy women aged 1840 years. A comprehensive clinical, laboratory and instrumental examination was performed, as well as an assessment of the composition of the GM using the cultural analysis method.
Results. In PCOS, a decrease in the GM diversity Margalef index was revealed compared to healthy women. A statistically significant decrease in the level of colonization of Bacteroides (B. vulgatus, B. eggerthii, B. caccae), Lactobacillus gasseri, Lacticaseibacillus rhamnosus, Escherichia coli (E.coli) and, on the contrary, an increase in the population of gamma-proteobacteria of the family Enterobacteriaceae and beta-proteobacteria of the order Burkholderiales, as well as Erysipelatoclostridium ramosum (E. ramosum), compared with healthy women. Correlation analysis revealed a negative correlation of bacteria of the genera Lactobacillus, Bifidobacterium, Bacteroides with IL-6, as well as E. coli with IL-6 and C-reactive protein in patients with PCOS. A positive correlation was observed between the level of IL-6 and the abundance of bacteria of the species E. ramosum.
Conclusions. The GM of PCOS patients is characterized by a decrease in Margalef diversity index, aggravated by the imbalance in microbial communities, accompanied by an increase in the levels of pro-inflammatory markers, compared with healthy women.