FXYD1 dysregulation impairs trophoblast function via a miR-486-3p-regulated axis in recurrent miscarriage

Recurrent miscarriage (RM) is a prevalent pregnancy complication with incompletely understood molecular mechanisms. Our prior work identified FXYD1 as a hub gene dysregulated in RM and its involvement in decidualization. Thus, this study aimed to characterize the functional role of FXYD1 in trophoblast biology and investigate a FXYD1-centered regulatory axis.

The expression levels of FXYD1 and miR-486-3p were evaluated in placental villous tissues from RM patients and gestational age-matched healthy controls. The HTR-8/SVneo cells, an immortalized human first-trimester extravillous trophoblast cell line, was utilized to assess the proliferation, migration and invasion capacities via CCK-8, wound healing, and Transwell assays, respectively. RNA sequencing was performed to characterize transcriptomic changes induced by FXYD1 overexpression.

The villous FXYD1 expression was significantly increased in RM patients. Functional assays revealed that FXYD1 overexpression impaired the proliferation, migration, and invasion capacities of HTR-8/SVneo cells. Subsequently, miR-486-3p was identified as an upstream regulator of FXYD1, and miR-486-3p overexpression partially rescued FXYD1-mediated suppression of those trophoblast functional phenotypes. Transcriptomic profiling following FXYD1 overexpression uncovered extensive differentially expressed genes, and gene set enrichment analysis (GSEA) indicated significant enrichment in signaling pathways, including Wnt, Hippo, Notch, and TGF-β signaling pathways, which are implicated in trophoblast regulation.

Collectively, this study preliminarily revealed FXYD1 serves as a potential regulator of trophoblast function and identifies the miR-486-3p/FXYD1 axis as a candidate molecular mechanism associated with trophoblast dysfunction. These findings provide new insights into the molecular mechanisms of RM and highlight possible directions for future therapeutic exploration.