Prediction of the response to controlled ovarian hyperstimulation through detection of serum microRNAs in patients undergoing in assisted reproductive procedures

The techniques of Assisted Human Reproduction (AHR) have been used by many couples who suffer from marital infertility. Intracytoplasmic Sperm Injection (ICSI) is the most widely used technique due to its effective treatment. For this purpose, the patients go through the Controlled Ovarian Stimulation (COS) protocol for oocyte recovery, but the responses to EOC protocols vary from absence to ovarian hyperstimulation, with clinical treatment complications. The measurement of serum markers is used to optimize the COS protocol, improving oocyte quality and reducing risks, however, there is still cancellation of AHR cycles. Studies suggest the biological role of microRNAs (miRNAs) in the control of ovarian functions. In addition, changes in the expression of miRNAs in blood plasma and follicular fluid of animal models submitted to COS have already been seen. However, the potential of these molecules as markers of response to COS for the treatment of infertility remains unclear. Thus, this project sought to evaluate the predictive potential of circulating miRNAs, in the serum of patients undergoing AHR cycles, in response to COS. Peripheral blood was collected from patients, before ovarian stimulation and, after COS, serum samples were classified into: group (1) normoresponsive (NR); (2) hyper response (HR); (3) poor response (PR). The fraction of small RNAs was isolated from the serum and subjected to large-scale detection of miRNAs by the qPCR Arrangement, in which 24 miRNAs presented differential detection between groups. Of these miRNAs, 10 were selected for further validation in an independent cohort of patients, with miRNAs miR-150-5p, miR-223-3p, let-7d-3p, miR-891a-5p, miR-99a-3p, miR-200c-5p candidates for predictors of poor response (PR) and miR-181d-5p, miR99a-5p, miR-221-3p, miR-92a-1-5p, candidates for exacerbated response (HR). Only the miRNA miR-181d-5p showed a difference in expression between groups, with significantly higher levels in the HR group compared to PR (p = 0.0001) and NR (p = 0.0079), and a positive correlation with aspects important clinical features such as the number of follicles aspirated (p <0.0001), recovered oocytes (p <0.0001) and mature oocytes (p = 0.0002). In addition, it was shown to be an independent predictor for hyperresponsiveness both with respect to NR (p = 0.002, AUC = 0.739) and PR (p <0.0001, AUC = 0.824), with a specificity of 86.2% and sensitivity 45%. miR-181d-5p targets predicted key members of important signaling pathways for female reproduction such as estrogen receptor (ESR1) and progesterone (PGR), insulin-like growth factor type 1 (IGF1), adenylate cyclase 1 (ADCY1) and epiregulin (EREG). Thus, the results indicate that the quantification of serum levels of miR-181d-5p may contribute to the prediction of the exacerbated response to Controlled Ovarian Stimulation (AU)