Puerarin alleviates symptoms of preeclampsia through the repression of trophoblast ferroptosis via the CREB/HO-1 pathway

Introduction: Preeclampsia (PE) is a pregnancy-associated complication characterised by new-onset hypertension and proteinuria. This study explored the therapeutic potential of puerarin (Pue) in PE and investigated the underlying mechanism, with a focus on placental Ferroptosis.

Methods: Using an N^G-nitro-L-arginine methyl ester (L-NAME)-induced PE mouse model, we assessed the effects of Pue on PE phenotypes and placental Ferroptosis. Antioxidative and anti-ferroptotic effects of Pue were studied in three ferroptotic cell models (hypoxia/reperfusion, cobalt chloride, and erastin). The regulation of Pue on cAMP response element binding protein (CREB) and heme oxygenase-1 (HO-1) was evaluated through gain- and loss-of-function assays. Luciferase assays were used to elucidate the effect of Flag-CREB on Hmox1 promoter fragments. CREB/HO-1 modulation by Pue was validated in mouse placentas with PE.

Results: Pue significantly alleviated maternal hypertension, proteinuria, fetal growth restriction, and placental damage in PE mice. This was associated with an upregulation of the anti-ferroptosis system (Glutathione Peroxidase 4 [GPX4], cys2/glutamate antiporter [SLC7A11], and glutathione [GSH]) and repression of Reactive Oxygen Species (ROS) and malondialdehyde (MDA) in trophoblasts. Pue reduced HO-1 and CREB, and HO-1 deficiency upregulated GPX4 and SLC7A11. Manipulation of CREB expression led to changes in HO-1/GPX4; whereas, the regulation reversed by Pue administration. Flag-CREB enhanced luciferase activity on the full length Hmox1 promoter (-2000/+78), which contains three CREB1 binding sites (S1-S3). In contrast, no increase in luciferase activity was observed with promoter fragments (-850/+78) and (-550/+78), which contain only the CREB1 binding sites S2 and S3, respectively.

Discussion: Pue ameliorated PE-like symptoms in mice by repressing trophoblast Ferroptosis via inhibition of CREB signalling and affecting the Homx1 promoter.

CREB; Ferroptosis; HO-1; Preeclampsia; Puerarin.