Anzi Tiaochong Tang inhibits trophoblast ferroptosis via the METTL14/m6A/SLC39A14 axis in recurrent spontaneous abortion.

PURPOSE: Recurrent spontaneous abortion (RSA) remains a major challenge in reproductive medicine, with unclear etiology in a substantial proportion of cases. Emerging evidence suggests that ferroptosis contributes to trophoblast dysfunction and may be involved in RSA pathogenesis. This study aimed to evaluate the therapeutic effects of Anzi Tiaochong Tang (AZTCT) on RSA and to elucidate its underlying molecular mechanisms, with a particular focus on ferroptosis.

METHODS

An RSA rat model was established using hydroxyurea and mifepristone to assess the therapeutic efficacy of AZTCT in vivo. For mechanistic investigation, ferroptosis was induced in human trophoblast HTR-8/SVneo cells using erastin. N6-methyladenosine methylation (m6A) was analyzed by bioinformatics, methylated RNA immunoprecipitation (MeRIP), and dual-luciferase reporter assays. Loss- and gain-of-function experiments, including METTL14 knockdown and SLC39A14 overexpression, were performed to validate the regulatory pathway.

RESULTS

AZTCT significantly improved pregnancy outcomes in RSA rats and enhanced trophoblast cell viability and migration while suppressing ferroptosis in vitro. Mechanistically, AZTCT upregulated METTL14 expression, which in turn increased m6A modification of SLC39A14 mRNA. This modification facilitated YTHDF2-dependent recognition, leading to reduced mRNA stability of SLC39A14. Functional rescue experiments further demonstrated that SLC39A14 overexpression reversed the protective effects mediated by METTL14.

CONCLUSION

AZTCT alleviates RSA, at least in part, by inhibiting trophoblast ferroptosis through the METTL14/m6A/YTHDF2/SLC39A14 axis. These findings provide mechanistic insight into the therapeutic potential of AZTCT and identify a novel epigenetic target for RSA treatment.