Serum microRNAs in male subfertility—biomarkers and a potential pathogenetic link to metabolic syndrome

PURPOSE: The purpose of the study was to identify serum microRNAs providing a link between male subfertility and metabolic syndrome (MetS) and validate their diagnostic potential. METHODS: Sera were analyzed for fertility and MetS-related parameters in subfertile men (n = 79) and controls (n = 38). Literature review identified miR-155-5p, miR-122-5p, miR-200a-3p, and miR-200c-3p which previously were associated with parameters of fertility as well as metabolic disorders. They were measured in the sera using an absolute quantitation method (qPCR). In order to investigate the value of miRNAs in predicting subfertility, receiver operating characteristic analysis was done. RESULTS: Subfertile men had higher concentrations of miR-155-5p than controls (p = 0.003) and for miR-200c-3p, the difference was borderline statistically significant (p = 0.05). miR-155-5p and miR-200c-3p were also associated with subfertility in men with no metabolic disturbances (p = 0.008, p = 0.004, respectively). This association was abrogated if any component of MetS was present. The combination of miR-155-5p and miR-200c-3p with follicle-stimulating hormone, being a well-established subfertility parameter, resulted in an overall diagnostic power of AUC = 0.87, which was even higher when men without MetS components were analyzed (AUC = 0.93). Regarding MetS components, statistically significant correlations were found between miR-122-5p and fasting triglycerides, and waist circumference, but no association with subfertility was identified. CONCLUSIONS: Among the four miRNAs analyzed, none of them was associated both with male subfertility and MetS components. The ability of miR-155-5p and miR-200c-3p to identify subfertile men was partly overruled by the presence of metabolic disturbances. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10815-017-0989-0) contains supplementary material, which is available to authorized users.