Ferroptosis is a recently identified non-apoptotic form of cell death characterized by iron-dependent lipid peroxidation. However, the underlying exact mechanisms remain poorly understood. Here, we report that the total levels of N⁶-methyladenosine (m⁶A) modification are evidently increased upon exposure to ferroptosis-inducing compounds due to the upregulation of methylase METTL4 and the downregulation of demethylase FTO. Interestingly, RNA-seq shows that m⁶A modification appears to trigger autophagy activation by stabilizing BECN1 mRNA, which may be the potential mechanism for m⁶A modification-enhanced HSC ferroptosis. Importantly, YTHDF1 is identified as a key m⁶A reader protein for BECN1 mRNA stability, and knockdown of YTHDF1 could prevent BECN1 plasmid-induced HSC ferroptosis. Noteworthy, YTHDF1 promotes BECN1 mRNA stability and autophagy activation via recognizing the m⁶A binding site within BECN1 coding regions. In mice, erastin treatment alleviates liver fibrosis by inducing HSC ferroptosis. HSC-specific inhibition of m⁶A modification could impair erastin-induced HSC ferroptosis in murine liver fibrosis. Moreover, we retrospectively analyzed the effect of sorafenib on HSC ferroptosis and m⁶A modification in advanced fibrotic patients with hepatocellular carcinoma (HCC) receiving sorafenib monotherapy. Attractively, the m⁶A modification upregulation, autophagy activation, and ferroptosis induction occur in human HSCs. Overall, these findings reveal novel signaling pathways and molecular mechanisms of ferroptosis, and also identify m⁶A modification-dependent ferroptosis as a potential target for the treatment of liver fibrosis.

铁死亡是最近发现的一种非凋亡形式的细胞死亡，其特征是铁依赖性脂质过氧化。然而，潜在的确切机制仍然知之甚少。在这里，我们报告说，由于甲基化酶 METTL4 的上调和去甲基化酶 FTO 的下调，N ⁶ - 甲基腺苷(m ⁶ A) 修饰的总水平在暴露于铁死亡诱导化合物后明显增加。有趣的是，RNA-seq 显示 m ⁶ A 修饰似乎通过稳定 BECN1 mRNA 来触发自噬激活，这可能是 m ⁶ A 修饰增强 HSC 铁死亡的潜在机制。重要的是，YTHDF1 被识别为键 m ⁶BECN1 mRNA 稳定性的读取蛋白和 YTHDF1 的敲低可以防止 BECN1 质粒诱导的 HSC 铁死亡。值得注意的是，YTHDF1 通过识别BECN1 编码区内的 m ⁶ A 结合位点来促进 BECN1 mRNA 稳定性和自噬激活。在小鼠中，erastin 治疗通过诱导 HSC 铁死亡来减轻肝纤维化。m ⁶ A 修饰的HSC 特异性抑制可能会损害鼠肝纤维化中由erastin 诱导的 HSC 铁死亡。此外，我们回顾性分析了索拉非尼对接受索拉非尼单药治疗的晚期肝细胞癌 (HCC) 纤维化患者HSC 铁死亡和 m ⁶ A 修饰的影响。有吸引力的是，m ⁶人类 HSC 中发生修饰上调、自噬激活和铁死亡诱导。总体而言，这些发现揭示了铁死亡的新信号通路和分子机制，并且还将 m ⁶ A 修饰依赖性铁死亡确定为治疗肝纤维化的潜在靶点。