Luoshi Neiyi prescription mitigates endometriosis by modulating nuclear receptor subfamily 5 group A member 1 methylation.

OBJECTIVE

This study aimed to investigate the mechanisms underlying Nuclear Receptor Subfamily 5 Group A Member 1 (NR5A1, encoding SF-1) hypomethylation in endometriosis (EMs) and to evaluate the effects of Luoshi Neiyi Prescription (LSNYP) on NR5A1 methylation.

METHODS

Endometriotic tissues were collected from patients, and primary endometrial stromal cells (ESCs) were isolated. A hypoxic microenvironment was induced in vitro using cobalt chloride (CoCl2), and lentiviral vectors targeting hypoxia-inducible factor 1 alpha (HIF1A; encoding HIF-1α) or enhancer of zeste homolog 2 (EZH2) were constructed. LSNYP-containing serum and a rat model of EMs were used to evaluate the effects of LSNYP.

RESULTS

HIF-1α and SF-1 were upregulated in endometriotic tissues and ectopic ESCs, whereas EZH2 was downregulated. Hypoxia increased SF-1 expression and E2 synthesis, but inhibited EZH2, DNA methyltransferase 1 (DNMT1), histone H3 lysine 27 trimethylation (H3K27me3), and NR5A1 methylation in eutopic ESCs. HIF1A knockdown upregulated EZH2 expression and NR5A1 promoter methylation. EZH2 knockdown reduced NR5A1 methylation and increased SF-1 expression and E2 synthesis. LSNYP decreased HIF-1α, SF-1, E2, TNF-α, MMP-3, and VEGF levels both in vitro and in vivo, while increasing EZH2 expression and NR5A1 promoter methylation. Interestingly, global 5-mC levels were not significantly altered.

CONCLUSION

Hypoxia-activated HIF-1α may downregulate EZH2 expression, thereby facilitating NR5A1 demethylation and increasing local E2 synthesis in EMs. LSNYP may exert therapeutic effects on EMs by alleviating hypoxia, enhancing NR5A1 methylation, and suppressing local E2 synthesis and inflammatory responses.