Ferroptosis-Related Proteins Are Potential Diagnostic Molecular Markers for Patients with Preeclampsia

Blocking lactate regulation of the Grhl2/SLC31A1 axis inhibits trophoblast cuproptosis and preeclampsia development

PURPOSE

Abnormal cell death due to superficial trophoblast dysfunction caused by placental hypoxia plays a vital role in the development of preeclampsia (PE). Lactic acid stimulates gene transcription in chromatin through lactate modification of histone lysine. Nevertheless, the content and function of lactate in PE development remains largely unclear.

METHODS

The contents of lactic acid and copper in 30 PE and 30 normal placentas were determined by kit colorimetry. Real-time quantitative fluorescent PCR (qRT-PCR) and Western blot were used to detect the expression of SLC31A1 in cells and tissues. Cell proliferation, apoptosis, and invasion were detected by cell counting kit 8 (CCK-8), MTS assay, colony formation assay, and Transwell assay. The transcriptional regulation between Grhl2 and SLC31A was verified by the luciferase reporter gene method and ChIP. The H3K18la modification level was detected by ChIP-PCR.

RESULTS

Herein, we detected increased lactic acid levels in the PE placental tissue, which inhibit the proliferation and invasion of trophoblasts. Interestingly, lactic acid increases intracellular copper content by enhancing the expression of SLC31A1, a key protein of copper ion transporters. Lentivirus knockdown of SLC31A1 blocked the lactate-induced proliferation and invasion of trophoblasts by inhibiting cell cuproptosis. Mechanically, we identified that Grhl2 mediated SLC31A1 expression through transcription and participated in SLC31A1-inhibited proliferation, invasion, and cuproptosis of trophoblasts. Furthermore, the high lactate content increased Grhl2 expression by enhancing lactate modification of histone H3K18 in the Grhl2 promoter region.

CONCLUSIONS

Blocking the lactate-regulated Grhl2/SLC31A1 axis and trophoblastic cuproptosis may be a potential approach to prevent and treat PE.

METTL3 promotes trophoblast ferroptosis in preeclampsia by stabilizing the ACSL4 m6A modification

This study aims to explore the role of methyltransferase-like 3 (METTL3) modulation of ferroptosis in the pathogenesis of trophoblast-mediated preeclampsia. The expression of METTL3 and acyl-CoA synthetase long chain family member 4 (ACSL4) was measured in clinical placental tissues and trophoblasts using qPCR and Western blot techniques. The effects of METTL3 on the symptoms of preeclampsia were also validated in rat models. METTL3 and ACSL4 were upregulated in placental tissues from patients with preeclampsia and in hypoxia-induced trophoblasts. METTL3 silencing increased the migration and invasion of trophoblasts cultured under hypoxic conditions. Knockdown of METTL3 increased cell viability and suppressed ferroptosis in hypoxia-stimulated trophoblasts. Hypoxia increased the level of m6A in cells, whereas silencing METTL3 partially reversed this change. Silencing METTL3 resulted in a decrease in m6A modification of ACSL4 mRNA, which led to a reduction in ACSL4 mRNA stability. ACSL4 upregulation partially reversed the effects of METTL3 silencing on cell viability, migration, invasion, and ferroptosis in hypoxia-stimulated trophoblasts. Inhibition of METTL3 in preeclampsia rats decreased blood pressure, urine protein levels, fetal survival rate, and ACSL4-mediated ferroptosis. METTL3 elevates ferroptosis to inhibit the migration and invasion of trophoblasts and in vivo preeclampsia symptoms by catalyzing the m6A modification of ACSL4 mRNA.

Type I interferon alters invasive extravillous trophoblast function

Inappropriate type I interferon (IFN) signaling during embryo implantation and placentation is linked to poor pregnancy outcomes. Here, we evaluated the consequence of elevated type I IFN exposure on implantation using a biomimetic model of human implantation in an organ-on-a-chip device. We found that type I IFN reduced extravillous trophoblast (EVT) invasion capacity. Analyzing single-cell transcriptomes, we uncovered that IFN truncated endovascular EVT emergence in the implantation-on-a-chip device by stunting EVT epithelial-to-mesenchymal transition. Disruptions to the epithelial-to-mesenchymal transition is associated with the pathogenesis of preeclampsia, a life-threatening hypertensive disorder of pregnancy. Strikingly, unwarranted IFN stimulation induced genes associated with increased preeclampsia risk and a preeclamptic gene-like signature in EVTs. These dysregulated EVT phenotypes ultimately reduced EVT-mediated endothelial cell vascular remodeling in the implantation-on-a-chip device. Overall, our work indicates IFN signaling can alter EVT epithelial-to-mesenchymal transition progression which results in diminished EVT-mediated spiral artery remodeling and a preeclampsia gene signature upon sustained stimulation. Our work implicates unwarranted type I IFN as a maternal disturbance that can result in abnormal EVT function that could trigger preeclampsia.