Knockdown of DDX46 inhibits trophoblast cell proliferation and migration through the PI3K/Akt/mTOR signaling pathway in preeclampsia

MicroRNA-510-3p regulated vascular dysfunction in Preeclampsia by targeting Vascular Endothelial Growth Factor A (VEGFA) and its signaling axis

INTRODUCTION

Preeclampsia (PE) is a pregnancy complication associated with multi-organ damage and vascular dysfunction. Meanwhile, microRNAs or miRNAs are crucial regulators of gene expression in various diseases including PE. Our previous studies reported high expression of miR-510 in the PE patients' blood compared to normal. Hence, we hypothesize that miR-510-3p targets Vascular endothelial growth factor A (VEGFA) in the regulation of PI3K/AKT/eNOS/mTOR axis in PE and miR-510-3p could be a potential therapeutic target for PE.

METHODS

The proliferation, migration, and apoptosis of HTR8/SVNeo and BeWo cells were analyzed by manipulating the miR-510-3p and VEGFA expression. Similarly, the inhibition of miR-510-3p through anti-miR-510-3p was analyzed in PE rat models, and the biochemical, hemodynamic parameters, and histopathology were examined between the groups. Moreover, the expression of miR-510-3p and VEGFA/PI3K/AKT/eNOS/mTOR axis was analyzed using qRT-PCR and Western blot.

RESULTS

Significant changes were observed in the BP, proteinuria, and other biochemical parameters between PE and control rats. Our results suggest that miR-510-3p targets VEGFA leading to vascular dysfunction in PE, while treatment with anti-miR-510-3p in the PE-induced rat model exhibits a significant change in the expression of miR-510-3p/VEGFA/PI3K/AKT/eNOS/mTOR signaling where miR-510-3p showed lesser expression and vice versa with VEGFA. The gene and protein expression analysis revealed a significant correlation between miR-510-3p and the VEGFA signaling axis in PE.

DISCUSSION

Thus, our findings from in vitro and in vivo suggest miR-510-3p as a potential therapeutic target and anti-miR-510-3p as a novel therapeutic molecule for PE.

MGST1 alleviates the oxidative stress of trophoblast cells induced by hypoxia/reoxygenation and promotes cell proliferation, migration, and invasion by activating the PI3K/AKT/mTOR pathway

Preeclampsia (PE) is a common pregnancy-specific syndrome with an incidence of 4.6% in all pregnant women. Numerous studies have uncovered the functions and mechanisms of microsomal glutathione transferase 1 (MGST1) in different diseases and cellular processes, but whether MGST1 plays a role in PE remains unclear. Our study aimed to investigate the regulatory role of MGST1 in PE progression. In this study, the HTR8/SVneo cells were incubated with CoCl₂ (250 µM) to mimic hypoxia in trophoblasts. Real-time quantitative polymerase chain reaction revealed that MGST1 was dramatically reduced in the placenta of PE patients. The proliferation of HTR8/SVneo cells was assessed via the Cell Counting Kit-8 and colony formation assays, and the results showed that MGST1 upregulation increased the cell viability of HTR8/SVneo cells. In addition, wound healing and Transwell assays unveiled that the elevation of MGST1 enhanced trophoblast cell migration and invasion. Moreover, the upregulation of MGST1 alleviated the hypoxia-induced oxidative stress in trophoblast cell. Mechanically, we found that MGST1 regulated PE progression by activating the phosphoinositide-3-kinase/protein kinase B/mechanistic target of rapamycin (PI3K/AKT/mTOR) pathway. In conclusion, MGST1 alleviated the oxidative stress of trophoblast cells induced by hypoxia/reoxygenation and promoted cell proliferation, migration, and invasion via the activation of the PI3K/AKT/mTOR pathway in PE. These results suggested that MGST1 can be a potential target for the prevention and treatment of PE.

Hypoxia-induced polarization of M2 macrophages and CCL5 secretion promotes the migration and invasion of trophoblasts

In the early stage of pregnancy, hypoxia in the placenta is of great significance to the migration and invasion of trophoblasts. In addition, changes to the polarity and activity of macrophages can affect embryo implantation, trophoblast migration and invasion, and vascular remodeling by affecting cytokine secretion. However, the mechanism of the effects of hypoxic conditions in the placenta on trophoblasts remains unknown. We used gene knockdown on macrophages, and drug treatment on trophoblasts, and cultured them under hypoxic and normoxic conditions. The cells were then subjected to wound healing assays, Transwell cell invasion experiments, quantitative real-time reverse transcription PCR, western blotting, and immunofluorescence. The polarization of macrophages in each group, the migration and invasion ability of trophoblasts, and changes to the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway were detected. Hypoxic conditions induce M2 polarization of macrophages. The conditioned medium from macrophages under hypoxic conditions increased the migration and invasion of trophoblasts, and enhanced the levels of phosphorylated (p)-PI3K and p-AKT in trophoblasts. After CCL5 knockdown in macrophages, the ability of conditioned medium from macrophages cultured under hypoxic conditions to promote the migration and invasion of trophoblasts was weakened significantly. The use of PI3K/AKT signaling pathway agonists could reverse the attenuation effect caused by CCL5 knockdown.

lncRNA DANCR promotes the migration an invasion and of trophoblast cells through microRNA-214-5p in preeclampsia

Studies have shown that lncRNA DANCR is down-regulated in placental tissues of patients with preeclampsia (PE). The aim of this study was to explore the effect of lncRNA DANCR on trophoblast cells as well as its acting mechanism. We disrupted or overexpressed lncRNA DANCR in trophoblast cells HTR-8/SVneo and JEG-3 and detected the associated cellular functional changes by MTT, flow cytometry, Transwell experiment, and scratch experiment. The results showed that overexpression of lncRNA DANCR significantly increased the proliferation, invasion, migration, and EMT process of trophoblast cells. Interfering with lncRNA DANCR showed the opposite result. Further, the targeted interaction between lncRNA DANCR and miR-214-5p was confirmed by the dual-luciferase reporter gene assay. In addition, the expression of PI3K/AKT signaling pathway-related proteins was analyzed by Western blot. Overexpression of lncRNA DANCR can increase the phosphorylation of PI3K/AKT protein and activate this signaling pathway. In conclusion, the enforcing of lncRNA DANCR activates the activation of the PI3K/AKT pathway by down-regulating miR-214-5p, and promotes the migration and invasion of chorionic trophoblast cells. This provides a potential new target for PE therapy.

Identification of downstream targets and signaling pathways of long non-coding RNA NR_002794 in human trophoblast cells

Preeclampsia (PE) is a huge threat to pregnant women. Our previous study demonstrated that long non-coding RNA (lncRNA) NR_002794 was highly expressed in placentas of PE patients and could regulate the phenotypes of trophoblast cells. However, the downstream regulatory mechanisms of NR_002794 remain unknown. In this text, some potential downstream targets or signaling pathways of NR_002794 were identified through RNA sequencing (RNA-seq) and bioinformatics analysis in SWAN71 trophoblast cells. Western blot assay demonstrated that NR_002794 inactivated protein kinase B (AKT) and extracellular signal-regulated kinase 1/2 (ERK1/2) pathways and activated cell apoptotic signaling in SWAN71 cells. Both RNA-seq and reverse transcription-quantitative PCR (RT-qPCR) outcomes showed that NR_002794 up-regulation could notably inhibit the expression of C-C motif chemokine ligand 4 like 2 (CCL4L2), interleukin 15 receptor subunit alpha (IL15RA), interleukin 32 (IL32), and tyrosine kinase with immunoglobulin-like and EGF-like domains 1 (TIE1), while NR_002794 knockdown induced these gene expressions in SWAN71 cells. CCK-8, BrdU, Transwell, wound healing, and flow cytometry analyses showed that NR_002794 inhibited cell proliferation and migration and induced cell apoptosis through down-regulating TIE1 in SWAN71 cells. In conclusion, lncRNA NR_002794 could exert its functions by regulating AKT and ERK1/2 pathways and TIE1 expression in human trophoblast cells.