Emodin alleviates endometrial fibrosis via METTL3/YTHDF2-mediated m6A modification of PPARα and the fatty acid oxidation pathway

Abstract

This study aimed to investigate the anti-fibrotic mechanism of emodin in endometrial stromal cells (ESCs), focusing on the N6-methyladenosine (m6A) modification of PPARα. An in vitro fibrosis model was established by treating ESCs with TGF-β1. Emodin was then administered to the cells, and its effects on fibrosis, cell viability, and fatty acid oxidation (FAO) were assessed. Subsequently, PPARα was silenced to evaluate the resulting changes in emodin’s therapeutic efficacy. Furthermore, MeRIP-qPCR was employed to examine the impact of emodin on m6A methylation of PPARα mRNA. The expression changes of key m6A regulatory molecules (METTL3, YTHDF2, IGF2BP2) were detected by qRT-PCR and Western blot. Finally, METTL3 and YTHDF2 were individually knocked down, and RIP-qPCR was conducted to investigate their specific regulatory roles on PPARα. Emodin attenuated fibrosis by reducing fibrotic markers and restoring PPARα/FAO pathway activity. PPARα knockdown abolished these effects. Mechanistically, emodin enhanced PPARα mRNA stability by reducing its m6A modification through downregulation of METTL3 and YTHDF2, and upregulation of IGF2BP2. Knockdown of METTL3 or YTHDF2 replicated emodin’s effects - increasing PPARα expression and stability while decreasing m6A modification. RIP-qPCR confirmed that METTL3 knockdown reduced YTHDF2 binding to PPARα mRNA. Emodin alleviates endometrial fibrosis by inhibiting METTL3/YTHDF2-mediated m6A modification of PPARα mRNA, thereby enhancing PPARα expression and promoting FAO-related gene expression, revealing its potential as a therapeutic agent for intrauterine adhesions.