Serum microRNAs in young women with polycystic ovary syndrome and their association with glucose metabolism.

INTRODUCTION: Polycystic ovary syndrome (PCOS) is associated with metabolic disturbances such as insulin resistance and prediabetes, and an increased risk is especially associated with hyperandrogenic phenotypes of PCOS. Circulating miRNAs may be involved in PCOS pathogenesis and regulation of metabolic processes.

OBJECTIVES: The aim of the study was to assess the expression levels of selected circulating miRNAs in women with PCOS and to investigate their relationship with glucose metabolism.

PATIENTS AND METHODS: The study included 95 PCOS patients with hyperandrogenism (HA-PCOS) and 76 healthy women similar in age and BMI. Sex hormone concentrations' measurements, oral glucose tolerance test, and transvaginal ultrasound were performed. Serum levels of selected miRNAs (miR-27a, miR-34a, miR-106b, miR-193b, miR-181a, miR-181b, miR-320) were assessed with real-time polymerase chain reaction, and their association with PCOS and glucose metabolism parameters was studied.

RESULTS: Serum levels of all studied miRNAs except miR-34a differed between patients with HA-PCOS and healthy women (all P<0.05). In HA-PCOS, miR-27a and miR-320 levels correlated with fasting glucose (R=0.33, P=0.001; R=-0.35, P <0.001) and insulin concentrations (R=0.26, P=0.01; R=-0.23, P=0.03). Additionally, the level of miR27a correlated with mean glucose concentration (R=0.26, P=0.01). No such correlations were observed in healthy women. In linear regression analyses, both miRNAs were associated with fasting glucose concentrations after adjustment for potentially confounding factors in the HA-PCOS group only.

CONCLUSIONS: The expression profile of circulating miRNAs is altered in HA-PCOS. Circulating miR-27a and miR-320 could possibly serve as potential biomarkers of glucose metabolism disturbances in PCOS.