P-517 Downregulated INHBB in endometrial tissue of recurrent implantation failure patients impeded decidualization through the ADCY1/cAMP signalling pathway

Abstract Study question To identify the mechanism of Inhibin Subunit Beta B (INHBB) in regulation human endometrial stromal cells (HESCs) decidualization recurrent implantation failure (RIF). Summary answer INHBB was decreased women with RIF, which attenuated vitro by suppressing ADCY1-induced cAMP production and cAMP-mediated signalling. What is known already encodes a preprotein subunit inhibin/ activin, functional cytokines belonging to transforming growth factor-β (TGF-β) family. mRNAs were expressed decidualized endometrium from first trimester pregnancy increased as gestation progressed. Furthermore, expression increases mouse uterus areas undergoing decidualization. These studies indicated that might play an essential role design, size, duration The Medical Ethics Committee Nanjing Drum Tower Hospital approved this study (No. 2013-081-01). Written informed consent obtained each participant. Between January 2020 November 2021, 28 infertile 18 fertile control aged 20-40 years normal regular menstrual cycles (25-35 days) no history steroid hormone medication last 3 months included study. Participants/materials, setting, methods RNA-seq conducted differentially genes endometria RIF patients. RT-qPCR, WB, immunohistochemistry performed analyse levels decidualised HESCs. RT-qPCR immunofluorescence used detect changes after knockdown INHBB. Then, dig out regulating decidualisation. Main results chance Our showed significantly reduced RIF. In addition, secretory phase induced in-vitro Notably, siRNA-mediated approaches, we demonstrated INHBB-ADCY1-mediated signalling pathway regulates reduction We found positive association between ADCY1 (R2= 0.3785, P = 0.0005). Limitations, reasons for caution level inducing ADCY1, while requires further exploration. Wider implications findings decline HESCs suppressed signalling, patients, indicating component process. Trial registration number not applicable