Purpose

Bronchopulmonary dysplasia (BPD) is associated with hyperoxia-induced oxidative stress-associated ferroptosis. This study examined the effect of E26 oncogene homolog 1 (ETS1) on oxidative stress-associated ferroptosis in BPD.

Methods

Hyperoxia-induced A549 cells and neonatal mice were used to establish BPD models. The effects of ETS1 on hyperoxia-induced ferroptosis-like changes in A549 cells were investigated by overexpression of ETS1 plasmid transfection and erastin treatment. Glucose consumption, lactate production, and NADPH levels were assessed by the glucose, lactate, and NADP⁺/NADPH assay kits, respectively. The potential regulatory relationship between ETS1 and Nrf2/HO-1 was examined by treating hyperoxia-induced A549 cells with the Nrf2 inhibitor ML385. ETS1 effect on the Nrf2 promoter was explored by dual-luciferase reporter and chromatin immunoprecipitation assay. The effect of ETS1 on the symptoms of BPD mice was examined by injecting an adenovirus overexpressing ETS1.

Results

ETS1 overexpression increased hyperoxia-induced cell viability, glucose consumption, lactate production, and NADPH levels and reduced inflammation and apoptosis in A549 cells. In animal experiments, ETS1 overexpression prevented weight loss, airway enlargement, and reductions in radial alveolar counts in BPD mice, while reducing the mean linear intercept, mean alveolar diameter and inflammation. ETS1 overexpression suppressed PTGS2 and CHAC1 expression, reduced ROS, MDA and ferrous iron (Fe²⁺) production and increased GSH levels in hyperoxia-induced A549 cells and BPD mice. In addition, ETS1 can bind to the Nrf2 promoter region and thus promote Nrf2 transcription. ETS1 overexpression increased the mRNA and protein levels of Nrf2, HO-1, xCT, and GPX4 in hyperoxia-induced A549 cells and BPD mice. In hyperoxia-induced A549 cells, erastin and ML385 treatment abolished the effect of ETS1 overexpression.

Conclusion

ETS1 is important in oxidative stress-related ferroptosis in a hyperoxia-induced BPD model, and the effect is partially mediated by the Nrf2/HO-1 axis.

中文翻译：

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ETS1 通过激活 Nrf2/HO-1 介导的铁死亡来改善高氧诱导的小鼠支气管肺发育不良

目的

支气管肺发育不良（BPD）与高氧诱导的氧化应激相关的铁死亡有关。本研究探讨了 E26 癌基因同源物 1 (ETS1) 对 BPD 中氧化应激相关铁死亡的影响。

方法

采用高氧诱导的A549细胞和新生小鼠建立BPD模型。通过过表达 ETS1 质粒转染和erastin 处理，研究 ETS1 对 A549 细胞中高氧诱导的铁死亡样变化的影响。分别通过葡萄糖、乳酸和 NADP ⁺ /NADPH 测定试剂盒评估葡萄糖消耗、乳酸产生和 NADPH 水平。通过用 Nrf2 抑制剂 ML385 处理高氧诱导的 A549 细胞，检查了 ETS1 和 Nrf2/HO-1 之间的潜在调节关系。通过双荧光素酶报告基因和染色质免疫沉淀测定探讨了 ETS1 对 Nrf2 启动子的影响。通过注射过表达 ETS1 的腺病毒来检查 ETS1 对 BPD 小鼠症状的影响。

结果

ETS1 过表达增加了高氧诱导的细胞活力、葡萄糖消耗、乳酸生成和 NADPH 水平，并减少了 A549 细胞中的炎症和细胞凋亡。在动物实验中，ETS1 过度表达可防止 BPD 小鼠体重减轻、气道扩张和径向肺泡计数减少，同时减少平均线性截距、平均肺泡直径和炎症。在高氧诱导的 A549 细胞和 BPD 小鼠中，ETS1 过表达抑制 PTGS2 和 CHAC1 表达，减少 ROS、MDA 和二价铁 (Fe ^{2+ ) 的产生，并增加 GSH 水平。}此外，ETS1可以与Nrf2启动子区域结合，从而促进Nrf2转录。ETS1 过表达增加了高氧诱导的 A549 细胞和 BPD 小鼠中 Nrf2、HO-1、xCT 和 GPX4 的 mRNA 和蛋白水平。在高氧诱导的 A549 细胞中，erastin 和 ML385 处理消除了 ETS1 过表达的影响。

结论

ETS1 在高氧诱导的 BPD 模型中与氧化应激相关的铁死亡中发挥重要作用，并且该作用部分由 Nrf2/HO-1 轴介导。