Metagenomic analysis identified microbiome alterations and pathological association between intestinal microbiota and polycystic ovary syndrome

Objective To identify different microbial species in women with polycystic ovary syndrome (PCOS) and reveal a possible relationship between gut dysbiosis and pathological changes. Design Cross-sectional study. Setting Academic institution. Patient(s) Reproductive-aged women with PCOS (n = 14) and controls (n = 14) from the Centre for Reproductive Medicine. Intervention(s) Shotgun metagenomic sequencing on fecal samples from patients, and clinical parameters (including body mass index, endocrine hormone levels, and glycemia level) gathered for correlation analysis. Main Outcome Measure(s) Identification of different gut microbial strains and relativity between microbiota and clinical parameters. Result(s) We found several microbial strains were statistically significantly more abundant in the PCOS group, including Parabacteroides merdae, Bacteroides fragilis, and strains of Escherichia and Shigella, whereas Faecalibacterium prausnitzii was enriched in the control group. Metagenomic species (MGS) analysis revealed that the microbes of the PCOS group were negatively correlated with those of the control group. Of note, we observed a positive correlation between MGS relevant to PCOS and endocrine disorders, including body mass index and elevated levels of serum testosterone, luteinizing hormone, and antimullerian hormone. Functional alterations, reflected by Kyoto Encyclopedia of Genes and Genomes orthologues, could imply potential mechanisms of microbial involvement in the developmental progress of PCOS. Conclusion(s) Our findings suggest an intimate association and potential mechanisms linking microbial dysbiosis and the pathophysiologic changes of PCOS. We address the importance of monitoring and modulating microbial composition and functional shifts in future clinical practice.