IGFBP1 inhibits the invasion, migration, and apoptosis of HTR-8/SVneo trophoblast cells in preeclampsia

The effects of metformin on inflammation and apoptosis in rats with preeclampsia

BACKGROUND

Defined clinically by elevated blood pressure along with either proteinuria and/or maternal organ dysfunction, representing a major cause of morbidity and mortality pregnant women and newborns. Metformin (MET), an oral antidiabetic medication, has been shown to prevent preeclampsia (PE) through various mechanisms, including reducing inflammation, improving endothelial dysfunction, improving mitochondrial function, and altering cellular homeostasis and energy metabolism. Herein, we explored the role of MET in PE and its underlying molecular mechanisms using in in vivo experiments.

METHODS

RT-qPCR, Western blot (WB), and immunohistochemistry (IHC) were conducted to assess the mRNA or protein expression of genes related to mitochondrial apoptosis. Additionally, ELISA was conducted to quantify the expression of mitochondrial apoptosis and inflammation-related genes, as well as PE biomarkers.

RESULTS

Treatment with MET in PE rats ameliorated hypertension and proteinuria, altered the expression of PE biomarkers, and significantly inhibited L-NAME-induced inflammation and cell apoptosis. MET modulated the levels of inflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, and IL-10, mitigating inflammation in PE rats. Furthermore, MET regulated mitochondrial outer membrane permeability (MOMP), thereby reducing cell apoptosis occurring in the mitochondrial pathway of PE rats.

CONCLUSIONS

This study demonstrates that MET alleviates inflammation and cell apoptosis in PE rats by modulating the expression of inflammatory factors and MOMP. Our results indicate that MET has huge therapeutic potential against PE.

Prediction of preeclampsia using maternal circulating mRNAs in early pregnancy

PURPOSE

Preeclampsia (PE) is one of the most common and serious complications of pregnancy, and novel methods for the early prediction of PE are needed for clinical application.

METHODS

In this study, a circulating cell-free RNA (cfRNA) panel of target genes for PE prediction was designed and validated in a case-control cohort and a nested case-control cohort. The QPCR was applied to quantify the copy number of cfRNA, and the data were normalized as multiples of the median. Ratios of serum placental growth factor (PIGF) and soluble fms-like tyrosine kinase 1 (sFLT-1) were also measured, and transabdominal ultrasonography was conducted for subjects in the prospective cohort. Binary logistic regression models for PE prediction were constructed and tested.

RESULTS

Our results revealed that the women with PE showed significant alterations in serum cfRNA profiles from early pregnancy onward and before the onset of PE symptoms. Compared with PIGF/sFLT-1 measurement and ultrasonographic imaging, cfRNA test can detect PE at a very early stage of pregnancy. The predictive model exhibited the best performance at gestation week 32, with a detection rate of 100%. At 12 weeks of gestation, the model still manifested an area under curve (AUC) of 0.9144, and sensitivity of 1.0000. If combined with clinical parameters and ultrasonographic indicators, the model can achieve the highest AUC for PE prediction at early gestation.

CONCLUSION

Measurement of cfRNA can be used to effectively predict PE with high performance, providing an additional method for monitoring PE throughout the course of pregnancy.

Phenylbutyric acid inhibits hypoxia-induced trophoblast apoptosis and autophagy in preeclampsia via the PERK/ATF-4/CHOP pathway

Preeclampsia (PE) is a common pregnancy complication with a high mortality rate. Abnormally activated endoplasmic reticulum stress (ERS) is believed to be responsible for the destruction of key placental cells-trophoblasts. Phenylbutyric acid (4-PBA), an ERS inhibitor, is involved in regulating the development of ERS-related diseases. At present, how 4-PBA affects trophoblasts and its mechanisms is still unclear. In this study, PE cell models were established by stimulating HTR-8/SVneo cells with hypoxia. To verify the underlying mechanisms of 4-PBA on PE, CCT020312, an activator of PERK, was also used. The results showed that 4-PBA restored hypoxia-induced trophoblast viability, inhibited HIF-1α protein expression, inflammation, and PERK/ATF-4/CHOP pathway. Hoechst 33342 staining and flow cytometry results confirmed that 4-PBA decreased hypoxia-induced apoptosis in trophoblasts. The results of the JC-1 analysis and apoptosis initiation enzyme activity assay also demonstrated that 4-PBA inhibited apoptosis related to the mitochondrial pathway. Furthermore, by detecting autophagy in trophoblasts, an increased number of autophagic vesicles, damaged mitochondria, enhanced dansylcadaverine fluorescence, enhanced levels of autophagy proteins Beclin-1, LC3II, and decreased p62 were seen in hypoxia-stimulated cells. These changes were reversed by 4-PBA. Furthermore, it was observed that CCT020312 reversed the effects of 4-PBA on the viability, apoptosis, and autophagosome number of hypoxia-induced trophoblasts. In summary, 4-PBA reduces autophagy and apoptosis via the PERK/ATF-4/CHOP pathway and mitochondrial pathway, thereby restoring the viability of hypoxic trophoblasts. These findings provide a solid evidence base for the use of 4-PBA in PE treatment and guide a new direction for improving the outcomes of patients with PE.

Morfofunctional and Molecular Changes in Placenta and Peripheral Blood in Preeclampsia and Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) and preeclampsia (PE) are common pregnancy complications with similar risk factors. Although GDM is associated with PE, the exact mechanism underlying the association is unclear. The objective of this work was to study the morphofunctional and molecular changes in the placenta and peripheral blood in PE and GDM. Local and systemic changes in the production of several placental proteins were assessed along with markers of inflammation and metabolic disorders. Expression of placental lactogen, trophoblastic β1-glycoprotein, placental alpha-1-microglobulin, and proteinase 3 in villi was found to change in complicated pregnancy groups. Similarity of underlying pathogenic mechanisms was demonstrated for PE and GDM.

Single-cell profiling reveals immune disturbances landscape and HLA-F-mediated immune tolerance at the maternal-fetal interface in preeclampsia

Background

Preeclampsia is a pregnancy-specific disorder that always causes maternal and fetal serious adverse outcome. Disturbances in maternal immune tolerance to embryo at the maternal-fetal interface (MFI) may be associated with preeclampsia onset. Recent studies have revealed the reduced expression pattern of HLA-F at the MFI in preeclampsia, while the mechanism of it mediating maternal fetal immune tolerance has not been revealed.

Methods

Single-cell RNA sequencing on placental decidua was performed to reveal the immune disturbances landscape at the MFI in preeclampsia. Human Jar cells and NK-92MI cells were employed to study the role of HLA-F in trophoblasts and lymphocyte.

Results

A total of 101,250 cells were classified into 22 cell clusters. Disease-related IGFBP1+SPP1+ extracellular villus trophoblast (EVT) was identified in the preeclamptic placental decidua, accompanied by newly discovered immune cellular dysfunction such as reduced ribosomal functions of NK populations and abnormal expression of antigen-presenting molecules in most cell clusters. Certain genes that are characteristic of the intermediate stage of myeloid or EVT cell differentiation were found to have unexplored but important functions in the pathogenesis of preeclampsia; specifically, we detected enhanced cell cross-talk between IGFBP1+SPP1+ EVT2 or SPP1+M1 cells and their receptor cell populations at the MFI of PE patients compared to controls. With respect to HLA-F, mIF staining confirmed its reduced expression in PE samples compared to controls. Over-expression of HLA-F in Jar cells promoted cell proliferation, invasion, and migration while under-expression had the opposite effect. In NK-92MI cells, over-expression of HLA-F increased the secretion of immunoregulation cytokines such as CSF1 and CCL22, and promoted adaptive NKG2C+NK cell transformation.

Conclusions

We revealed the immune disturbance landscape at the MFI in preeclampsia. Our findings regarding cellular heterogeneity and immune cellular dysfunction, as revealed by scRNA-seq, and the function of HLA-F in cells provide new perspectives for further investigation of their roles in the pathogenesis of preeclampsia, and then provide potential new therapeutic target.

Associations between IGFBP1 gene polymorphisms and the risk of preeclampsia and fetal growth restriction

IGFBP1 plays a critical role in the pathogenesis of preeclampsia (PE), but the association between single nucleotide polymorphism (SNP) of IGFBP1 gene and PE susceptibility has not yet been determined. In our study, 229 women with PE and 361 healthy pregnant (non-PE) women were enrolled to investigate its association via TaqMan genotyping assay. In addition, the protein levels of IGFBP1 under different genotypes were explored by ELISA and IHC. We found that IGFBP1 SNP rs1065780A > G was associated with an decreased risk for PE. Women with GG (P = 0.027) or AG (Padj. = 0.023) genotype manifested a significantly lower risk for PE compared to women with AA genotype. In PE group, women carrying G allele exhibited greater fetal birth weight, lower diastolic BP, and lower levels of ALT and AST. The G genotype was found significantly less frequently in the severe preeclampsia (SPE) group than in the non-PE group (GG vs. AA, P = 0.007; G vs. A, P = 0.006). Additionally, women in the PE group who experienced fetal growth restriction (FGR) reflected a lower level of the allele G than did the non-FGR group (P = 0.032); this was not the case for the non-PE group.Rs1065780A>G elevated IGFBP1 protein level in plasma and decidua in PE group. In conclusion Chinese Han women with the SNP IGFBP1 rs1065780 occupied by G exhibited a lower risk of developing PE relative to women with the A genotype and augured for improved pregnancy outcomes through elevation of IGFBP1 protein level.

miR‑424‑5p is downregulated in the placentas of patients with preeclampsia and affects trophoblast migration and invasion

Insufficient invasion of trophoblast cells has been reported to be closely associated with the pathogenesis of preeclampsia (PE). MicroRNAs (miRs) have essential roles in the trophoblasts invasion via targeting specific genes with diverse functions. However, the underlying mechanism remains largely unclear and requires further investigation. The present study aimed to identify and evaluate the potential functions of miRs in trophoblasts invasion and to reveal the underlying mechanisms. In the present study, differentially expressed miRs that were screened based on previously published microarray data (GSE96985) and a significantly downregulated miR-424-5p (miR-424) was chosen for further investigation. Subsequently, reverse transcription-quantitative PCR, CCK-8, apoptosis, wound healing and Transwell assays were performed to determine the cell viability, apoptotic rate, cell migration and invasion of trophoblast cells. The results showed that miR-424 was decreased in placenta specimens from patients with PE. Upregulation of miR-424 promoted cell viability, suppressed cell apoptosis and improved the invasion and migration of trophoblasts, whereas inhibition of miR-424 had opposite results. Adenomatous polyposis coli (APC), a key mediator of Wnt/β-catenin signaling pathway, was identified as a functional target of miR-424 and an inverse relationship was observed between APC and miR-424 in placenta specimens. Further investigations revealed that APC overexpression efficiently suppressed the effect of miR-424 in trophoblast cells. In addition, the miR-424-mediated effects on trophoblast cells were dependent on the promotion of Wnt/β-catenin signaling pathway. The present findings revealed that miR-424 regulates the trophoblast cell invasion by regulating Wnt/β-catenin pathway through targeting APC, indicating miR-424 as a potential candidate for the treatment of PE.