Serum expression levels of selected microRNAs and their association with glucose metabolism in young women with polycystic ovary syndrome.

Introduction: Polycystic ovary syndrome (PCOS) is associated with metabolic disturbances, such as insulin resistance and prediabetes, and the risk for their occurrence is especially increased in hyperandrogenic (HA) phenotypes of PCOS. Circulating microRNAs (miRNAs) may be involved in PCOS pathogenesis and regulation of metabolic processes.

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

Patients And Methods: The study included 95 patients with HA‑PCOS and 76 healthy women similar to the study group in age and body mass index. Measurements of sex hormone concentrations, oral glucose tolerance test (OGTT), and transvaginal ultrasonography were performed. Serum levels of selected miRNAs (miR‑27a, miR‑34a, miR‑106b, miR‑193b, miR‑181a, miR‑181b, and 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 for miR‑34a, differed between the 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 and R = -0.35; P <0.001, respectively) and insulin concentrations (R = 0.26; P = 0.01 and R = -0.23; P = 0.03, respectively). Additionally, the level of miR‑27a correlated with mean glucose concentration during OGTT (R = 0.26; P = 0.01). No such correlations were observed in the healthy women. In linear regression analyses, both miR‑27a and miR‑320 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 patients with HA‑PCOS. Circulating miR‑27a and miR‑320 could serve as potential biomarkers of glucose metabolism disturbances in PCOS.