Identification of several circulating microRNAs from a genome-wide circulating microRNA expression profile as potential biomarkers for impaired glucose metabolism in polycystic ovarian syndrome.

This study aimed to detect serum microRNAs (miRNAs) differentially expressed between polycystic ovary syndrome (PCOS) patients with impaired glucose metabolism (IGM), PCOS patients with normal glucose tolerance (NGT), and healthy controls. A TaqMan miRNA array explored serum miRNA profiles as a pilot study, then selected miRNAs were analyzed in a validation cohort consisting of 65 PCOS women with IGM, 65 PCOS women with NGT, and 45 healthy women The relative expression of miR-122, miR-193b, and miR-194 was up-regulated in PCOS patients compared with controls, whereas that of miR-199b-5p was down-regulated. Furthermore, miR-122, miR-193b, and miR-194 were increased in the PCOS-IGM group compared with the PCOS-NGT group. Multiple linear regression analyses revealed that miR-193b and body mass index contributed independently to explain 43.7 % (P < 0.0001) of homeostasis model assessment-insulin resistance after adjustment for age. Investigation of diagnostic values confirmed the optimal combination of BMI and miR-193b to explore the possibility of IGM in PCOS women with area under the curve of 0.752 (95 % CI 0.667-0.837, P < 0.001). Bioinformatics analysis indicated that the predicted target functions of these miRNAs mainly involved glycometabolism and ovarian follicle development pathways, including the insulin signaling pathway, the neurotrophin signaling pathway, the PI3K-AKT signaling pathway, and regulation of actin cytoskeleton. This study expands our knowledge of the serum miRNA expression profiles of PCOS patients with IGM and the predicted target signal pathways involved in disease pathophysiology.