心肌成纤维细胞通过分泌靶向 SLC7A11 的外泌体 miR-23a-3p 促进心房颤动中的铁死亡。
Cardiac Fibroblasts Promote Ferroptosis in Atrial Fibrillation by Secreting Exo-miR-23a-3p Targeting SLC7A11.
机构信息
Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, China.
Cardiovascular Research Institute, Wuhan University, Wuhan 430060, China.
出版信息
Oxid Med Cell Longev. 2022 May 29;2022:3961495. doi: 10.1155/2022/3961495. eCollection 2022.
The exact mechanism of atrial fibrillation (AF) has been not well elucidated. Ferroptosis is an iron-dependent cell death due to excessive accumulation of peroxidized polyunsaturated fatty acids. However, the molecular mechanism underlying AF and ferroptosis has never been reported. Here, we established the rapid pacing model in vivo and vitro to investigate the relationship between AF and ferroptosis. In canine model of rapid atrial pacing, the content of malondialdehyde and total ions in the atrial tissue of the Pacing group was significantly increased and the exosome inhibitor GW4869 reduced ferroptosis, fibrosis, and inflammation and improved histological and electrophysiological remodeling. In rapid pacing h9c2 cells, the expression of antioxidative stress genes associated with ferroptosis presented sequential changes and proteins involved in ferroptosis such as FTH1, SLC7A11, and GPX4 were gradually depleted. Furthermore, pacing cardiac fibroblast-derived exosomes (CF-exos) exacerbated ferroptosis in h9c2 cells and pretreated pacing-CF-exos with GW4869 alleviated injury to h9c2 cells. In mechanism, our results demonstrated that pacing-CF-exos highly expressed miR-23a-3p by informatics analysis and experimental verification. Inhibitor-miR-23a-3p protected h9c2 cells from ferroptosis accompanying with upregulation of SLC7A11. In addition, SLC7A11 was shown to be the target gene of miR-23a-3p. In conclusion, our results suggest that CF-exos-miR-23a-3p may promote ferroptosis. The development of AF in a persistent direction could be prevented by intervening with exosomal miRNAs to reduce oxidative stress injury and ferroptosis.
心房颤动(AF)的确切机制尚未阐明。铁死亡是由于过氧化物聚不饱和脂肪酸的积累而导致的铁依赖性细胞死亡。然而,AF 和铁死亡的分子机制从未被报道过。在这里,我们建立了体内和体外快速起搏模型,以研究 AF 和铁死亡之间的关系。在快速起搏的犬模型中,起搏组心房组织中的丙二醛和总离子含量明显增加,外泌体抑制剂 GW4869 减少了铁死亡、纤维化和炎症,并改善了组织学和电生理重构。在快速起搏的 h9c2 细胞中,与铁死亡相关的抗氧化应激基因的表达呈现出顺序变化,并且铁死亡涉及的蛋白质,如 FTH1、SLC7A11 和 GPX4,逐渐耗尽。此外,起搏心肌成纤维细胞衍生的外泌体(CF-exos)加剧了 h9c2 细胞中的铁死亡,并且用 GW4869 预处理起搏-CF-exos 减轻了 h9c2 细胞的损伤。在机制上,我们的结果表明,通过信息学分析和实验验证,起搏-CF-exos 高度表达 miR-23a-3p。抑制剂-miR-23a-3p 保护 h9c2 细胞免受铁死亡,同时上调 SLC7A11。此外,SLC7A11 被证明是 miR-23a-3p 的靶基因。总之,我们的结果表明,CF-exos-miR-23a-3p 可能促进铁死亡。通过干预外泌体 miRNAs 来减少氧化应激损伤和铁死亡,可以预防 AF 向持续方向发展。