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.