College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, Fujian 350001, China; Fujian Maternity and Child Health Hospital, Fuzhou, Fujian 350001, China; Fujian Clinical Research Center for Maternal-Fetal Medicine, Fuzhou, Fujian 350001, China; Laboratory of Maternal-Fetal Medicine, Fujian Maternity and Child Health Hospital, Fuzhou, Fujian 350001, China; National Key Obstetric Clinical Specialty Construction Institution of China, Fuzhou, Fujian 350001, China.
College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, Fujian 350001, China; Fujian Maternity and Child Health Hospital, Fuzhou, Fujian 350001, China.
Life Sci. 2024 Apr 15;343:122555. doi: 10.1016/j.lfs.2024.122555. Epub 2024 Mar 7.
Ferroptosis, a novel mode of cell death characterized by lipid peroxidation and oxidative stress, plays an important role in the pathogenesis of preeclampsia (PE). The aim of this study is to determine the role of Nox2 in the ferroptosis of trophoblast cells, along with the underlying mechanisms.
The mRNA and protein levels of Nox2, STAT3, and GPX4 in placental tissues and trophoblast cells were respectively detected by qRT-PCR and western blot analysis. CCK8, transwell invasion and tube formation assays were used to evaluate the function of trophoblast cells. Ferroptosis was evaluated using flow cytometry and the lipid peroxidation assay. Glycolysis and mitochondrial respiration were investigated by detecting the extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) using Seahorse extracellular flux technology. The t-test or one-way ANOVA was used for statistical analysis.
Nox2 was up-regulated while STAT3 and GPX4 were down-regulated in PE placental tissues. Nox2 knockdown inhibited ferroptosis in trophoblast cells, which was shown by enhanced proliferation and invasion, decreased ROS and lipid peroxide levels, and reduced glycolysis and mitochondrial dysfunction. Nox2 negatively correlated with MVD in PE placentas, and Nox2 knockdown restored ferroptosis-inhibited tube formation. Nox2 could interact with STAT3. Inhibiting Nox2 restored ferroptosis-induced alterations in the mRNA and protein levels of STAT3 and GPX4.
Nox2 may trigger ferroptosis through the STAT3/GPX4 pathway, subsequently leading to regulation of mitochondrial respiration, transition of glycolysis, and inhibition of placental angiogenesis. Therefore, targeted inhibition of Nox2 is expected to become a new therapeutic target for PE.
铁死亡是一种新型的细胞死亡方式，其特征为脂质过氧化和氧化应激，在子痫前期（PE）的发病机制中发挥重要作用。本研究旨在确定 Nox2 在滋养细胞铁死亡中的作用及其潜在机制。
采用 qRT-PCR 和 Western blot 分析检测胎盘组织和滋养细胞中 Nox2、STAT3 和 GPX4 的 mRNA 和蛋白水平。CCK8 法、Transwell 侵袭和管形成实验用于评估滋养细胞的功能。采用流式细胞术和脂质过氧化检测评估铁死亡。使用 Seahorse 细胞外通量技术检测细胞外酸化率（ECAR）和耗氧量（OCR）来研究糖酵解和线粒体呼吸。采用 t 检验或单因素方差分析进行统计学分析。
PE 胎盘组织中 Nox2 上调，STAT3 和 GPX4 下调。Nox2 敲低抑制了滋养细胞的铁死亡，表现为增殖和侵袭能力增强，ROS 和脂质过氧化物水平降低，糖酵解和线粒体功能障碍减少。Nox2 与 PE 胎盘的 MVD 呈负相关，Nox2 敲低恢复了铁死亡抑制的管形成。Nox2 可与 STAT3 相互作用。抑制 Nox2 恢复了铁死亡诱导的 STAT3 和 GPX4 的 mRNA 和蛋白水平的改变。
Nox2 可能通过 STAT3/GPX4 通路引发铁死亡，进而调节线粒体呼吸、糖酵解转变，并抑制胎盘血管生成。因此，靶向抑制 Nox2 有望成为治疗 PE 的新靶点。
