Pathogenesis of preeclampsia: the genetic component

Association of angiogenic factors (placental growth factor and soluble FMS-like tyrosine kinase-1) in preeclamptic women of African ancestry comorbid with HIV infection

BACKGROUND

Preeclampsia is a significant cause of maternal and fetal morbidity and mortality, particularly in low- and middle-income countries like South Africa.

AIM

The aim of our study was to investigate the association between placental growth factor (PlGF) and soluble FMS-like tyrosine kinase-1 (sFlt-1) in South African preeclamptic women of African ancestry, comorbid with HIV infection.

METHODS

The study population consisted of women attending a regional hospital in Durban, South Africa, stratified by pregnancy type (normotensive pregnant and preeclampsia) and HIV status. Preeclampsia was defined as new-onset hypertension and proteinuria. DNA was obtained from whole blood. The SNPs of interest were rs722503 in sFlt-1 and rs4903273 in PlGF.

RESULTS

Our findings suggest that single nucleotide polymorphisms of rs722503 analysis show no significant associations between the genotypic frequencies of rs722503 variants and preeclampsia risk in either HIV-negative or HIV-positive groups of women of African ancestry. Similarly, the rs493273 polymorphism showed no significant association with preeclampsia risk in either HIV-negative or HIV-positive pregnant women. Additionally, comparisons of dominant, recessive, and over-dominant allele models did not reveal significant associations. These findings suggest that these genetic variants may not significantly contribute to preeclampsia development in this African ancestry population. However, significant differences were observed in the rs4903273 genotype frequencies between normotensive and preeclamptic women, regardless of HIV status, over dominant alleles AA + GG vs AG showed a significant difference [OR = 2.706; 95% Cl (1.199-5.979); adjusted p = 0.0234*], also in normotensive compared to EOPE (OR = 2.804; 95% Cl (1.151-6.89) p = 0.0326* and LOPE (OR = 2.601; 95% Cl (1.0310-6.539) p = 0.0492*), suggesting that they may be the potential role of this variant in preeclampsia susceptibility.

CONCLUSION

The findings suggest that the rs722503 and rs493273 polymorphisms do not significantly contribute to preeclampsia susceptibility in HIV-negative or HIV-positive pregnant women. However, the rs4903273 genotype frequencies showed notable differences between normotensive and preeclamptic women, indicating a potential association with preeclampsia development in the African ancestry population irrespective of HIV status.

Association of cardiovascular risk factors and myocardial hypertrophy in women with preeclampsia history

AIMS

A historic of preeclampsia (PE) has been associated with cardiovascular disease (CVD) in women. There are substantial evidences that cardiovascular changes resulting from PE can persist even after pregnancy end. Therefore, the aims was to evaluate the prevalence of myocardial hypertrophy in young women 12 months after PE event as well as try to identify risk factors for these changes.

MATERIALS AND METHODS

Single-center observational prospective cross-sectional study that included 118 consecutive patients after 12 months of PE. Clinical and laboratory evaluations, echocardiogram were performed. Myocardial hypertrophy (LVH) was defined as an index myocardial mass ≥ 45 g/m2.7, for women. Classical risk factors for CVD were considered. Analysis included linear or logistic regression and Spearman's correlation coefficient. Significance level of 5 %.

KEY FINDINGS

Systemic arterial hypertension (SAH) was identified in 52 patients (44 %), overweight/obesity (OOB) in 82 (69 %), dyslipidemia in 68 (57 %) and metabolic syndrome in 47 patients (40 %). LVH was present in 35 cases (29 %) and associated with OOB (OR = 4.51; CI95%:1.18-17.17, p < 0.001), in a model corrected for age and SAH diagnosis. When only the metabolic syndrome components were analyzed, in the multiple logistic regression model, the abdominal circumference was the only clinical variable associated with LVH (OR = 17.65; CI95%:3.70-84.17; p < 0.001).

SIGNIFICANCE

It was observed a high prevalence of ventricular hypertrophy in young women with a history of pre-eclampsia. This condition was associated with the presence of obesity.

Effect of the CYBA C242T Polymorphism on Preeclampsia Pathogenesis in the Chinese Population

BACKGROUND

Although the mechanisms responsible for the pathogenesis of preeclampsia (PE) have not been entirely clarified, oxidative stress is thought to be its leading cause. As a major component responsible for reactive oxygen species (ROS) production during oxidative stress, p22phox, encoded by CYBA, is an essential subunit of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. The aim of this study was to investigate whether CYBA expression and its polymorphism are associated with PE.

METHODS

Expression of CYBA was analysed in placentas from PE and control groups, as well as in HTR-8/SVneo cells stimulated with CoCl2 and TNF-α. Then, the CYBA C242T polymorphism in 1184 patients with PE and 1421 healthy controls was genotyped using the TaqMan probe, and the different distributions identified were confirmed by a case‒control association study.

RESULTS

Expression of CYBA mRNA and protein in the placenta of pregnant women with PE was significantly increased compared to controls. Expression of CYBA mRNA was also increased in HTR-8/SVneo cells collected after 24 h of separate stimulation with cobalt chloride and TNF-α. There was no significant difference in the distribution of the C242T locus genotype and CYBA allele frequency between the case group and control group (P > 0.05).

CONCLUSIONS

CYBA may play a role in the pathogenesis of oxidative stress in PE, in which it may function by cooperating with the TNF-α-related inflammatory pathway. Although no discrepant distribution of the CYBA C242T polymorphism in the Chinese population was detected, it is necessary to examine multiple CYBA SNPs in diverse populations and perform functional experiments to gain further insights into its pathogenesis.

Downregulated PDIA3P1 lncRNA Impairs Trophoblast Phenotype by Regulating Snail and SFRP1 in PE

Preeclampsia (PE) manifests as a pregnancy-specific complication arising from compromised placentation characterized by inadequate trophoblast invasion. A growing body of evidence underscores the pivotal involvement of pseudogenes, a subset of long noncoding RNAs, in the pathological processes of PE. This study presents a novel finding, demonstrating a significant downregulation of the pseudogene PDIA3P1 in PE placental tissues compared to normal tissues. In vitro functional assays revealed that suppressing PDIA3P1 hindered trophoblast proliferation, invasion, and migration, concurrently upregulating the expression of secreted frizzled-related protein 1 (SFRP1). Further exploration of the regulatory role of PDIA3P1 in PE, utilizing human trophoblasts, established that PDIA3P1 exerts its function by binding to HuR, thereby enhancing the stability of Snail expression in trophoblasts. Overall, our findings suggest a crucial role for PDIA3P1 in regulating trophoblast properties and contributing to the pathogenesis of PE, offering potential targets for prognosis and therapeutic intervention.

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.

Protective role of complement factor H against the development of preeclampsia

Pregnancy is an immunologically regulated, complex process. A tightly controlled complement system plays a crucial role in the successful establishment of pregnancy and parturition. Complement inhibitors at the feto-maternal interface are likely to prevent inappropriate complement activation to protect the fetus. In the present study, we aimed to understand the role of Factor H (FH), a negative regulator of complement activation, in normal pregnancy and in a model of pathological pregnancy, i.e. preeclampsia (PE). The distribution and expression of FH was investigated in placental tissues, various placental cells, and in the sera of healthy (CTRL) or PE pregnant women via immunohistochemistry, RT-qPCR, ELISA, and Western blot. Our results showed a differential expression of FH among the placental cell types, decidual stromal cells (DSCs), decidual endothelial cells (DECs), and extravillous trophoblasts (EVTs). Interestingly, FH was found to be considerably less expressed in the placental tissues of PE patients compared to normal placental tissue both at mRNA and protein levels. Similar results were obtained by measuring circulating FH levels in the sera of third trimester CTRL and PE mothers. Syncytiotrophoblast microvesicles, isolated from the placental tissues of PE and CTRL women, downregulated FH expression by DECs. The present study appears to suggest that FH is ubiquitously present in the normal placenta and plays a homeostatic role during pregnancy.

Characteristics of Serum Lipid Metabolism among Women Complicated with Hypertensive Disorders in Pregnancy: A Retrospective Cohort Study in Mainland China

Background

Altered maternal serum lipid metabolism is associated with hypertensive disorders in pregnancy (HDP). However, its range in pregnancy and characteristic among different subgroups of HDPs are unclear.

Methods

Pregnant women with HDP who underwent antenatal care and delivered in Obstetrics and Gynecology Hospital of Fudan University during January 2018 to August 2022 were enrolled. The levels of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol (LDLC), apolipoprotein (Apo)-A, B, and E, free fatty acids (FFA), and small and dense low-density lipoprotein cholesterol (sdLDL) were measured during 4-16 weeks and 28-42 weeks of pregnancy.

Results

A total of 2648 pregnant women were diagnosed with HDP, 1,880 of whom were enrolled for final analysis, including 983 (52.3%) preeclampsia (PE), 676 (36.0%) gestational hypertension (GH), and 221 (11.7%) chronic hypertension (CH). For all HDPs, serum TC, TG, LDLC, HDLC, Apo-A, Apo-B, Apo-E, and sdLDL increased significantly during pregnancy, while FFA decreased significantly. Notably, the levels of TC, LDLC, Apo-B, and sdLDL in PE group were equal to or lower than those in CH group at 4-16 weeks of pregnancy, but increased greatly during pregnancy (P < 0.05).

Conclusions

Maternal serum lipid levels changed through pregnancy among women with HDPs. Women complicated with PE seem to have undergone a more significant serum lipid change compared to those with GH or CH.

The role of genetics in maternal susceptibility to preeclampsia in women of African ancestry

Racial disparities exist in the prevalence of preeclampsia (PE), with women of African ancestry suffering the highest rates of morbidity and mortality. Genetic changes may play a role in the preponderance of PE among women of African ancestry. This review discusses 30 genes with variants that have been studied in PE in women of African ancestry. These studies found that a single gene is not responsible for PE susceptibility as 13 genes have been implicated. These genes subserve endothelial, immune, hemodynamic, homeostatic, thrombophilic, oxidative stress, and lipid metabolic pathways. Notably, maternal-fetal gene interactions also contribute to the susceptibility of the disease. For instance, the maternal KIR AA genotype and paternally inherited fetal HLA-C2 genotype confer risk for developing PE. Additionally, genetic changes such as epigenetic modulation of expression of the MTHFR gene through DNA methylation is also associated with the occurrence of PE. In contrast, some genes such as the KIR B centromeric region protect against development of PE in some women. The soluble fms-like tyrosine kinase 1 (sFlt-1) contributes to the development of PE and is a potential novel therapeutic option for targeted gene silencing of anti-angiogenic sFLT-1 gene. Additionally, NOS3 gene is an important target for pharmacogenomics because it is responsible for the production of endothelial nitric oxide. In conclusion, maternal genetic and epigenetic variants confer susceptibility to PE, indicating the need for further studies to develop a screening tool incorporating maternal genetic variants to identify women at high risk for PE and offer them a preventive therapy.

Progress in Research on Biomarkers of Gestational Diabetes Mellitus and Preeclampsia

Gestational diabetes mellitus (GDM) and preeclampsia (PE) are common complications in pregnancy, with incidence rates of 1-5% and 9.4%, respectively, in China. Both these phenomena can cause adverse pregnancy outcomes and are extremely harmful to the mother and fetus. In this study, we observed that several predictive factors have important value in GDM and PE. Among the GDM group, abnormal levels of adiponectin (APN), C-reactive protein (CRP), and Leptin were observed. The coexistence of PE and GDM in the pregnant population is not uncommon. Ultimately, we discovered abnormal levels of factors such as Visfatin, Advanced oxidative protein product (AOPP), Fibroblast growth factor 21 (FGF21), and resistin in both GDM and PE groups. Particularly, the FGF21 factor holds significant importance in our research. Therefore, we need to complete the analysis and discussion of relevant predictive factors to enable early prediction and disease monitoring of GDM, PE, and other pregnancy-related disorders, ultimately contributing to the long-term health of pregnant women.

Genomic variation associated with cardiovascular disease progression following preeclampsia: a systematic review

Background

Women with a history of preeclampsia (PE) have been shown to have up to five times the risk of developing later-life cardiovascular disease (CVD). While PE and CVD are known to share clinical and molecular characteristics, there are limited studies investigating their shared genomics (genetics, epigenetics or transcriptomics) variation over time. Therefore, we sought to systematically review the literature to identify longitudinal studies focused on the genomic progression to CVD following PE.

Methods

A literature search of primary sources through PubMed, Scopus, Web of Science and Embase via OVID was performed. Studies published from January 1, 1980, to July 28, 2023, that investigated genomics in PE and CVD were eligible for inclusion. Included studies were screened based on Cochrane systematic review guidelines in conjunction with the PRISMA 2020 checklist. Eligible articles were further assessed for quality using the Newcastle-Ottawa scale.

Results

A total of 9,231 articles were screened, with 14 studies subjected to quality assessment. Following further evaluation, six studies were included for the final review. All six of these studies were heterogeneous in regard to CVD/risk factor as outcome, gene mapping approach, and in different targeted genes. The associated genes were RGS2, LPA, and AQP3, alongside microRNAs miR-122-5p, miR-126-3p, miR-146a-5p, and miR-206. Additionally, 12 differentially methylated regions potentially linked to later-life CVD following PE were identified. The only common variable across all six studies was the use of a case-control study design.

Conclusions

Our results provide critical insight into the heterogeneous nature of genomic studies investigating CVD following PE and highlight the urgent need for longitudinal studies to further investigate the genetic variation underlying the progression to CVD following PE.

Immunoexpression of neuropilin-1 in the chorionic villi of HIV-infected preeclamptic South African women of African ancestry

Neuropilin-1 (NRP-1) is an essential regulator of maternal immune tolerance, placentation, and angiogenesis. Its dysregulation in preeclampsia (PE) and human immunodeficiency virus (HIV) infection implicates NRP-1 in disease susceptibility and progression. Therefore, this study investigates placental NRP-1 immunoexpression in HIV-complicated preeclamptic pregnancies in South African women of African ancestry receiving antiretroviral therapy. Immunohistochemistry of recombinant anti-neuropilin-1 antibody was performed on placental tissue from 30 normotensive and 60 early onset (EOPE) and late-onset (LOPE) preeclamptic women stratified by HIV status. Qualitative analysis of NRP-1 immunostaining within the chorionic villi revealed a predominant localization in trophoblasts and syncytial knots as well as endothelial, fibroblast-like, and Hofbauer cells. Following morphometric evaluation, we report that PE and HIV infection and/or antiretroviral usage independently downregulate placental NRP-1 immunoexpression; however, as a comorbidity, this decline is further augmented within the conducting and exchange villi. Furthermore, reduced immunoexpression of NRP-1 in EOPE compared with LOPE villi may be due to maternal-fetal maladaptation. It is plausible that the decreased NRP-1 immunoexpression in PE placentae facilitates syncytiotrophoblast apoptosis and subsequent deportation of NRP-1 into the maternal circulation, contributing to the anti-angiogenic milieu of PE. We hypothesize that the intense NRP-1 immunoreactivity observed in Hofbauer cells at the maternal-fetal interface may contribute to the natural prevention mechanism of HIV vertical transmission.

The eNOS-G894T genetic polymorphism and risk of preeclampsia: A case-control study, an updated meta-analysis, and a bioinformatic assay

OBJECTIVES

Preeclampsia (PE) is a leading cause of maternal death worldwide and involves vascular endothelial dysfunction. The aim of this study was to investigate the association of the G894T polymorphism in the endothelial nitric oxide synthase (eNOS) gene and the risk of preeclampsia in a case-control design in an Iranian population, which was followed by a meta-analysis and an in silico approach.

METHODS

In the case-control study, 300 people including 135 pregnant women with preeclampsia and 165 healthy pregnant women were included. The genotype of G894T polymorphism was determined by the PCR-RFLP method. We searched authoritative scientific databases to find eligible studies for meta-analysis. The odds ratio with a 95% confidence interval was estimated to find the strength of the association of the mentioned polymorphism with the risk of preeclampsia. In addition, the effect of G894T transversion on eNOS gene function was evaluated by some bioinformatics tools.

RESULTS

Our case-control data showed that the G894T polymorphism is associated with an increased risk of preeclampsia. In the meta-analysis, 33 eligible studies were included, and the results showed that the G894T polymorphism is associated with an increased risk of preeclampsia in the overall analysis and some stratified analyses. In addition, the structural analysis showed that the G894T variant can affect the splicing process as well as the protein stability.

CONCLUSIONS

Based on the results, the aforementioned polymorphism may be a risk factor for preeclampsia and could be considered a potential molecular biomarker for screening susceptible individuals.

Leptin Promotes HTR-8/SVneo Cell Invasion via the Crosstalk between MTA1/WNT and PI3K/AKT Pathways

The process of placental invasion is essential for a successful pregnancy. Leptin is involved in trophoblast invasiveness, and its dysregulation is connected with a series of diseases, including preeclampsia. However, the knowledge of the precise mechanisms in leptin-induced trophoblast invasiveness is still limited. According to the present research, transwell assay suggested that leptin is a dose- and time-dependent regulator in inducing HTR-8/SVneo cell invasion. Western blot analysis and immunofluorescence staining revealed that leptin-induced MMP9 expression is essential in the invasion process of HTR-8/SVneo cells. Mechanistically, we demonstrated that leptin activated β-catenin via the crosstalk between the MTA1/WNT and PI3K/AKT pathways. Besides, we showed that downregulating the key molecules in the signaling pathways by siRNA can inhibit leptin-induced MMP9 expression and further suppress invasion of HTR-8/SVneo cells. In conclusion, our study revealed a new regulatory mechanism of leptin-induced HTR-8/SVneo cell invasiveness and will provide novel insights into the causes and potential therapeutic targets for diseases related to dysregulation of trophoblast invasion in the future.

Efficiency of sFlt-1/PlGF Ratio in Preeclampsia Diagnosis

Background and Objectives: Preeclampsia is a health issue characterized by a new onset of hypertension after 20 weeks of gestation and proteinuria. This is a multiple organ disorder and is associated with significant maternal and fetal mortality. Material and Methods: The study is a prospective one and included 69 pregnant women (17 with hypertension without criteria for PE, 26 with severe PE and 26 with moderate PE) with an age of gestation between 24 and 40 weeks. Subjects were chosen from those who referred to the Oradea County Emergency Clinical Hospital, Department of Obstetrics-Gynecology between January 2020 and December 2022. We collected other characteristics from observation sheets and from patients and we measured the sFlt-1/PlGF ratio after 20 weeks of pregnancy if patients presented with suspected preeclampsia. All the results were collected in Excel analysis by SPSS. Results: In our study, 37.68% had severe preeclampsia, the same percentage had moderate PE and 24.63% presented only with hypertension. The mean of sFLT-1/PlGF for severe preeclampsia was 78.282 ng/mL, and for moderate, it was 50.154 ng/mL. For those who did not have criteria for preeclampsia, it was 29.076 ng/mL. When we compared the values of sFLT-1/PlGF in moderate PE and hypertension, we found that there was a statistically significant difference between this two, and the same conclusion was also obtained for severe PE and hypertension and for severe and moderate PE. Conclusions: This marker can be useful for improving the outcomes for pregnant women with preeclampsia. In addition, for newborns, sFlt-1/PlGF can be helpful because we can correctly and promptly manage a patient affected by this disease before 34 weeks of pregnancy. Our study demonstrates that the correlation between the values of sFlt-1/PlGF and the type of preeclampsia are positive; thus, if the values are high, the pregnant woman likely will develop severe preeclampsia with early onset. In addition, the sFlt-1/PlGF ratio has the highest accuracy for differentiating PE patients from pregnant women who did not develop sign and symptoms for preeclampsia. Our results are in line with the conclusions of other studies that researched the association between sFlt-1/PlGF and clinical diagnosis of preeclampsia.

Association of Single Nucleotide Polymorphisms from Angiogenesis-Related Genes, ANGPT2, TLR2 and TLR9, with Spontaneous Preterm Labor

In this study, we hypothesized that the changes localized at angiopoietin-2 (ANGPT2), granulocyte-macrophage colony-stimulating factor (CSF2), fms-related tyrosine kinase 1 (FLT1) and toll-like receptor (TLR) 2, TLR6 and TLR9 genes were associated with spontaneous preterm labor (PTL), as well as with possible genetic alterations on PTL-related coagulation. This case-control genetic association study aimed to identify single nucleotide polymorphisms (SNPs) for the aforementioned genes, which are correlated with genetic risk or protection against PTL in Polish women. The study was conducted in 320 patients treated between 2016 and 2020, including 160 women with PTL and 160 term controls in labor. We found that ANGPT2 rs3020221 AA homozygotes were significantly less common in PTL cases than in controls, especially after adjusting for activated partial thromboplastin time (APTT) and platelet (PLT) parameters. TC heterozygotes for TLR2 rs3804099 were associated with PTL after correcting for anemia, vaginal bleeding, and history of threatened miscarriage or PTL. TC and CC genotypes in TLR9 rs187084 were significantly less common in women with PTL, compared to the controls, after adjusting for bleeding and gestational diabetes. For the first time, it was shown that three polymorphisms-ANGPT2 rs3020221, TLR2 rs3804099 and TLR9 rs187084 -were significantly associated with PTL, adjusted by pregnancy development influencing factors.

Clotting factor genes are associated with preeclampsia in high-altitude pregnant women in the Peruvian Andes

Preeclampsia is a multi-organ complication of pregnancy characterized by sudden hypertension and proteinuria that is among the leading causes of preterm delivery and maternal morbidity and mortality worldwide. The heterogeneity of preeclampsia poses a challenge for understanding its etiology and molecular basis. Intriguingly, risk for the condition increases in high-altitude regions such as the Peruvian Andes. To investigate the genetic basis of preeclampsia in a population living at high altitude, we characterized genome-wide variation in a cohort of preeclamptic and healthy Andean families (n = 883) from Puno, Peru, a city located above 3,800 meters of altitude. Our study collected genomic DNA and medical records from case-control trios and duos in local hospital settings. We generated genotype data for 439,314 SNPs, determined global ancestry patterns, and mapped associations between genetic variants and preeclampsia phenotypes. A transmission disequilibrium test (TDT) revealed variants near genes of biological importance for placental and blood vessel function. The top candidate region was found on chromosome 13 of the fetal genome and contains clotting factor genes PROZ, F7, and F10. These findings provide supporting evidence that common genetic variants within coagulation genes play an important role in preeclampsia. A selection scan revealed a potential adaptive signal around the ADAM12 locus on chromosome 10, implicated in pregnancy disorders. Our discovery of an association in a functional pathway relevant to pregnancy physiology in an understudied population of Native American origin demonstrates the increased power of family-based study design and underscores the importance of conducting genetic research in diverse populations.

Protein Network Analysis of Whole Exome Sequencing of Severe Preeclampsia

Preeclampsia is a hypertensive disorder of pregnancy, which complicates up to 15% of US deliveries. It is an idiopathic disorder associated with several different phenotypes. We sought to determine if the genetic architecture of preeclampsia can be described by clusters of patients with variants in genes in shared protein interaction networks. We performed a case-control study using whole exome sequencing on early onset preeclamptic mothers with severe clinical features and control mothers with uncomplicated pregnancies between 2016 and 2020. A total of 143 patients were enrolled, 61 women with early onset preeclampsia with severe features based on ACOG criteria, and 82 control women at term, matched for race and ethnicity. A network analysis and visualization tool, Proteinarium, was used to confirm there are clusters of patients with shared gene networks associated with severe preeclampsia. The majority of the sequenced patients appear in two significant clusters. We identified one case dominant and one control dominant cluster. Thirteen genes were unique to the case dominated cluster. Among these genes, LAMB2, PTK2, RAC1, QSOX1, FN1, and VCAM1 have known associations with the pathogenic mechanisms of preeclampsia. Using bioinformatic analysis, we were able to identify subsets of patients with shared protein interaction networks, thus confirming our hypothesis about the genetic architecture of preeclampsia.

Immunological Changes in Pregnancy and Prospects of Therapeutic Pla-Xosomes in Adverse Pregnancy Outcomes

Stringent balance of the immune system is a key regulatory factor in defining successful implantation, fetal development, and timely parturition. Interference in these primary regulatory mechanisms, either at adolescence or prenatal state led to adverse pregnancy outcomes. Fertility restoration with the help of injectable gonadotrophins/progesterone, ovulation-inducing drugs, immunomodulatory drugs (corticosteroids), and reproductive surgeries provides inadequate responses, which manifest its own side effects. The development of a potential diagnostic biomarker and an effectual treatment for adverse pregnancy outcomes is a prerequisite to maternal and child health. Parent cell originated bi-layered-intraluminal nano-vesicles (30-150 nm) also known as exosomes are detected in all types of bodily fluids like blood, saliva, breast milk, urine, etc. Exosomes being the most biological residual structures with the least cytotoxicity are loaded with cargo in the form of RNAs (miRNAs), proteins (cytokines), hormones (estrogen, progesterone, etc.), cDNAs, and metabolites making them chief molecules of cell-cell communication. Their keen involvement in the regulation of biological processes has portrayed them as the power shots of cues to understand the disease's pathophysiology and progression. Recent studies have demonstrated the role of immunexosomes (immunomodulating exosomes) in maintaining unwavering immune homeostasis between the mother and developing fetus for a healthy pregnancy. Moreover, the concentration and size of the exosomes are extensively studied in adverse pregnancies like preeclampsia, gestational diabetes mellitus (GDM), and preterm premature rupture of membrane (pPROMs) as an early diagnostic marker, thus giving in-depth information about their pathophysiology. Exosomes have also been engineered physically as well as genetically to enhance their encapsulation efficiency and specificity in therapy for cancer and adverse pregnancies. Successful bench to bedside discoveries and interventions in cancer has motivated developmental biologists to investigate the role of immunexosomes and their active components. Our review summarizes the pre-clinical studies for the use of these power-shots as therapeutic agents. We envisage that these studies will pave the path for the use of immunexosomes in clinical settings for reproductive problems that arise due to immune perturbance in homeostasis either at adolescence or prenatal state.

The role of platelet parameters for the diagnosis of preeclampsia among pregnant women attending at the University of Gondar Comprehensive Specialized Hospital antenatal care unit, Gondar, Ethiopia

Background

Preeclampsia (PE) is a pregnancy‐related illness characterized by high blood pressure (BP) and proteinuria after the 20th gestational week (GW). Platelet (PLT) parameter changes are the common hematological abnormalities observed in PE patients. The main aim of this study was to assess the role of PLT parameters for PE diagnosis among pregnant women.

Methods

A comparative cross‐sectional study was conducted at the University of Gondar Specialized Hospital. A total of 126 pregnant women (63 normotensive [NT] and 63 PE) were recruited using a convenient sampling method. Three milliliter blood was collected from each participant, and PLT parameters were determined using Sysmex XS‐500i analyzer. An independent t‐test supplemented with receiver‐operating characteristics (ROC) were used for comparisons and diagnostic value of PLT parameters between the study groups.

Results

Platelet count (PC) was significantly lower in the PE group compared to that in the NT group, whereas mean platelet volume (MPV), platelet large cell ratio (P‐LCR), and platelet distribution width (PDW) were significantly higher in PE. MPV had the largest area under the curve (AUC) [0.91: 95% CI; 0.85–0.96] followed by PC [0.79: 95% CI; 0.72–0.87]. MPV can differentiate PE patients from NT pregnant women at cut‐off value ≥12.10 fl (84.1% sensitivity and 87.3% specificity) while PC can indicate PE at a cut‐off value ≤176.5 × 10⁹/L (65.1% sensitivity and 87.3% specificity).

Conclusion

A decreased PC and an increased MPV, P‐LCR, and PDW can be used as a simple, cost‐effective, quick, and reliable method of PE screening. Of them, MPV is the best indicator of PE.

Preeclampsia, Natural History, Genes, and miRNAs Associated with the Syndrome

Preeclampsia (PE) is a hypertensive disease that affects pregnant women after 20 weeks of gestation. This disease is associated with an important risk of maternal and fetal mortality. PE is described as a placental pathology because, after delivery, most women recover normal arterial pressure. Poor invasion of the spiral arteries is a phenomenon well described in PE; this leads to a hypoxic uterine bed and imbalance of antiangiogenic and proangiogenic factors in the uteroplacental region, which in turn triggers the disease phenotype. The causes of the pathology are unclear; nevertheless, numerous approaches, including next-generation sequencing, association, and case control and miRNA studies, have shed light on the genetic/molecular basis of PE. These studies help us better understand the disease to advance new treatment strategies.

Associations between AGT, MTHFR, and VEGF gene polymorphisms and preeclampsia in the Chinese population

INTRODUCTION

Preeclampsia (PE) is a pregnancy-specific multisystemic syndrome. This study aimed to investigate the associations between angiotensinogen (AGT), methylenetetrahydrofolate reductase (MTHFR), vascular endothelial growth factor (VEGF) polymorphisms, and PE in the Han Chinese population.

METHODS

We genotyped 26 single-nucleotide polymorphisms (SNP) in three genes by using QuantStudio™ 12 K Flex Real-Time PCR technology in 168 patients with PE and 204 healthy pregnant control subjects. The associations of tested polymorphisms with PE were analyzed at allele, genotype, and haplotype levels.

RESULTS

A common coding variant in MTHFR, rs2274976, was significantly associated with increased risk of PE in both allelic and genotype models (P < 0.05). The heterozygous genotypes of rs699 (G/A vs G/G) in AGT gene and rs3025035 (C/T vs C/C) in VEGF gene showed weak associations with increased PE risk, whereas the mutant homozygous genotype of rs3024987 (TT vs C/C) and the heterozygous genotype of rs3025039 (C/T vs C/C) in VEGF gene displayed weak associations with decreased PE risk (P < 0.05).

DISCUSSION

However, these weak associations lost significance after multiple testing correction. The results indicated that rs2274976 in MTHFR gene may contribute to the increased risk of PE in pregnant women. AGT and VEGF gene polymorphisms may not play a significant role in PE development.

OUP accepted manuscript

Preeclampsia is a pregnancy-specific disease that can have serious effects on the health of both mothers and their offspring. Predicting which women will develop preeclampsia in early pregnancy with high accuracy will allow for improved management. The clinical symptoms of preeclampsia are well recognized, however, the precise molecular mechanisms leading to the disorder are poorly understood. This is compounded by the heterogeneous nature of preeclampsia onset, timing and severity. Indeed a multitude of poorly defined causes including genetic components implicates etiologic factors, such as immune maladaptation, placental ischemia and increased oxidative stress. Large datasets generated by microarray and next-generation sequencing have enabled the comprehensive study of preeclampsia at the molecular level. However, computational approaches to simultaneously analyze the preeclampsia transcriptomic and network data and identify clinically relevant information are currently limited. In this paper, we proposed a control theory method to identify potential preeclampsia-associated genes based on both transcriptomic and network data. First, we built a preeclampsia gene regulatory network and analyzed its controllability. We then defined two types of critical preeclampsia-associated genes that play important roles in the constructed preeclampsia-specific network. Benchmarking against differential expression, betweenness centrality and hub analysis we demonstrated that the proposed method may offer novel insights compared with other standard approaches. Next, we investigated subtype specific genes for early and late onset preeclampsia. This control theory approach could contribute to a further understanding of the molecular mechanisms contributing to preeclampsia.

Supraphysiological Role of Melatonin Over Vascular Dysfunction of Pregnancy, a New Therapeutic Agent?

Hypertension can be induced by the disruption of factors in blood pressure regulation. This includes several systems such as Neurohumoral, Renin-angiotensin-aldosterone, the Circadian clock, and melatonin production, which can induce elevation and non-dipping blood pressure. Melatonin has a supraphysiological role as a chronobiotic agent and modulates vascular system processes via pro/antiangiogenic factors, inflammation, the immune system, and oxidative stress regulation. An elevation of melatonin production is observed during pregnancy, modulating the placenta and fetus’s physiological functions. Their impairment production can induce temporal desynchronization of cell proliferation, differentiation, or invasion from trophoblast cells results in vascular insufficiencies, elevating the risk of poor fetal/placental development. Several genes are associated with vascular disease and hypertension during pregnancy via impaired inflammatory response, hypoxia, and oxidative stress, such as cytokines/chemokines IL-1β, IL-6, IL-8, and impairment expression in endothelial cells/VSMCs of HIF1α and eNOS genes. Pathological placentas showed differentially expressed genes (DEG), including vascular genes as CITED2, VEGF, PL-II, PIGF, sFLT-1, and sENG, oncogene JUNB, scaffolding protein CUL7, GPER1, and the pathways of SIRT/AMPK and MAPK/ERK. Additionally, we observed modification of subunits of NADPH oxidase and extracellular matrix elements, i.e., Glypican and Heparanase and KCa channel. Mothers with a low level of melatonin showed low production of proangiogenic factor VEGF, increasing the risk of preeclampsia, premature birth, and abortion. In contrast, melatonin supplementation can reduce systolic pressure, prevent oxidative stress, induce the activation of the antioxidants system, and lessen proteinuria and serum level of sFlt-1. Moreover, melatonin can repair the endothelial damage from preeclampsia at the placenta level, increasing PIGF, Nrf-2, HO-1 production and reducing critical markers of vascular injury during the pregnancy. Melatonin also restores the umbilical and uterine blood flow after oxidative stress and inhibits vascular inflammation and VCAM-1, Activin-A, and sEng production. The beneficial effects of melatonin over pathological pregnancies can be partially observed in normal pregnancies, suggesting the dual role of/over placental physiology could contribute to protection and have therapeutic applications in vascular pathologies of pregnancies in the future.

Preeclampsia: From Cellular Wellness to Inappropriate Cell Death, and the Roles of Nutrition

Preeclampsia is one of the most common obstetrical complications worldwide. The pathomechanism of this disease begins with abnormal placentation in early pregnancy, which is associated with inappropriate decidualization, vasculogenesis, angiogenesis, and spiral artery remodeling, leading to endothelial dysfunction. In these processes, appropriate cellular deaths have been proposed to play a pivotal role, including apoptosis and autophagy. The proper functioning of these physiological cell deaths for placentation depends on the wellbeing of the trophoblasts, affected by the structural and functional integrity of each cellular component including the cell membrane, mitochondria, endoplasmic reticulum, genetics, and epigenetics. This cellular wellness, which includes optimal cellular integrity and function, is heavily influenced by nutritional adequacy. In contrast, nutritional deficiencies may result in the alteration of plasma membrane, mitochondrial dysfunction, endoplasmic reticulum stress, and changes in gene expression, DNA methylation, and miRNA expression, as well as weakened defense against environmental contaminants, hence inducing a series of inappropriate cellular deaths such as abnormal apoptosis and necrosis, and autophagy dysfunction and resulting in abnormal trophoblast invasion. Despite their inherent connection, the currently available studies examined the functions of each organelle, the cellular death mechanisms and the nutrition involved, both physiologically in the placenta and in preeclampsia, separately. Therefore, this review aims to comprehensively discuss the relationship between each organelle in maintaining the physiological cell death mechanisms and the nutrition involved, and the interconnection between the disruptions in the cellular organelles and inappropriate cell death mechanisms, resulting in poor trophoblast invasion and differentiation, as seen in preeclampsia.

Association of IL-10 -819C/T, -592A/C polymorphisms with the risk of preeclampsia: An updated meta-analysis

OBJECTIVE

The purpose of our study was to investigate whether IL-10 -819C/T, -592A/C polymorphisms were associated with preeclampsia (PE) susceptibility.

METHODS

A comprehensive and systematic literature search was performed through online databases, including Web of Science, PubMed, EMBASE, and Chinese databases. Then eligible literatures were included according to inclusion criteria and exclusion criteria. Statistical data analysis was performed using Stata 10.0 software. Odds ratios (OR) and 95% confidence interval were applied to evaluated the association between IL-10 -819C/T, -592A/C polymorphisms and PE susceptibility.

RESULTS

According to inclusion and exclusion criteria, 9 case-control studies, including 1423 cases and 2031 controls, were included in this meta-analysis. Our meta-analysis revealed that no association was found between IL-10 -819C/T, -592A/C polymorphisms and the risk of PE in our study.

CONCLUSION

Our meta-analysis suggested that IL-10 -819C/T and -592A/C polymorphisms had no association with PE susceptibility, but had a significant association with PE susceptibility in Asian and Caucasian.

Non-Coding RNAs in Preeclampsia-Molecular Mechanisms and Diagnostic Potential

Preeclampsia (PE) is a leading cause of maternal and neonatal morbidity and mortality worldwide. Defects in trophoblast invasion, differentiation of extravillous trophoblasts and spiral artery remodeling are key factors in PE development. Currently there are no predictive biomarkers clinically available for PE. Recent technological advancements empowered transcriptome exploration and led to the discovery of numerous non-coding RNA species of which microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are the most investigated. They are implicated in the regulation of numerous cellular functions, and as such are being extensively explored as potential biomarkers for various diseases. Altered expression of numerous lncRNAs and miRNAs in placenta has been related to pathophysiological processes that occur in preeclampsia. In the following text we offer summary of the latest knowledge of the molecular mechanism by which lnRNAs and miRNAs (focusing on the chromosome 19 miRNA cluster (C19MC)) contribute to pathophysiology of PE development and their potential utility as biomarkers of PE, with special focus on sample selection and techniques for the quantification of lncRNAs and miRNAs in maternal circulation.

Gene Polymorphism in Five Target Genes of Immunosuppressive Therapy and Risk of Development of Preeclampsia

Pregnancy can be considered as an allogeneic transplant and preeclampsia can be seen as a failure of the acceptance mechanisms of this transplant as occurs in acute organ transplant rejection. Some genetic polymorphisms may be involved in its pathogenesis. Since the kidney is one of the organs mainly involved in preeclampsia, our study attempted to determine the frequencies of single nucleotide polymorphisms of DNA (SNP) in 3 genes (adenosine triphosphate-binding cassette sub-family B member 1 (ABCB1)/multi drug reactivity 1 (MDR1) gene, interleukin 10 gene and tumor necrosis factor α gene) which are targets of immunosuppressive therapies and related to acute renal rejection. The study was an observational, monocentric, case-control study. We enrolled 20 women with severe preeclampsia and 10 women age-matched with regular pregnancy. Continuous variables were compared by the Student’s t-test for independent variables or using the Mann-Whitney test depending on their distribution. We used Fisher test to compare categorical variables between cases and controls, while we used logistic regression model to evaluate which risk factor was associated with preeclampsia. Although there was no statistically significant difference between the two groups, we found different percentages of two of the polymorphisms considered (rs1045642 and rs2032582 in the gene ABCB1). Despite these results, our work may be helpful for future research to better understand the pathogenesis of preeclampsia.

Maternal endothelial dysfunction in HIV-associated preeclampsia comorbid with COVID-19: a review

This review assesses markers of endothelial dysfunction (ED) associated with the maternal syndrome of preeclampsia (PE). We evaluate the role of antiretroviral therapy (ART) in human immunodeficiency virus (HIV)-infected preeclamptic women. Furthermore, we briefly discuss the potential of lopinavir/ritonavir (LPV/r), dolutegravir (DTG) and remdesivir (RDV) in drug repurposing and their safety in pregnancy complicated by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In HIV infection, the trans-activator of transcription protein, which has homology with vascular endothelial growth factor, impairs angiogenesis, leading to endothelial injury and possible PE development despite neutralization of their opposing immune states. Markers of ED show strong evidence supporting the adverse role of ART in PE development and mortality compared to treatment-naïve pregnancies. Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2 infection, exploits angiotensin-converting enzyme 2 (ACE 2) to induce ED and hypertension, thereby mimicking angiotensin II-mediated PE in severe cases of infection. Upregulated ACE 2 in pregnancy is a possible risk factor for SARS-CoV-2 infection and subsequent PE development. The potential effectiveness of LPV/r against COVID-19 is inconclusive; however, defective decidualization, along with elevated markers of ED, was observed. Therefore, the safety of these drugs in HIV-positive pregnancies complicated by COVID-19 requires attention. Despite the observed endothelial protective properties of DTG, there is a lack of evidence of its effects on pregnancy and COVID-19 therapeutics. Understanding RDV-ART interactions and the inclusion of pregnant women in antiviral drug repurposing trials is essential. This review provides a platform for further research on PE in the HIV-COVID-19 syndemic.

Comparative risks and predictors of preeclamptic pregnancy in the Eastern, Western and developing world

Preeclampsia (PE) is a complication of pregnancy characterized by hypertension (HTN-Preg), and often proteinuria. If not managed promptly, PE could lead to eclampsia and seizures. PE could also lead to intrauterine growth restriction (IUGR) and prematurity at birth. Although PE is a major cause of maternal and fetal morbidity and mortality, the underlying mechanisms are unclear. Also, there is a wide variability in the incidence of PE, ranging between 2 and 8% of pregnancies in the Eastern, Western and Developing world, suggesting regional differences in the risk factors and predictors of the pregnancy-related disorder. Several demographic, genetic, dietary and environmental factors, as well as maternal circulating biomarkers have been associated with PE. Demographic factors such as maternal race and ethnicity could play a role in PE. Specific genetic polymorphisms have been identified in PE. Maternal age, parity, education and socioeconomic status could be involved in PE. Dietary fat, protein, calcium and vitamins, body weight, and environmental factors including climate changes and air pollutants could also play a role in PE. Several circulating cytoactive factors including anti-angiogenic factors and cytokines have also been associated with PE. Traditional midwifery care is a common practice in local maternity care units, while advanced perinatal care and new diagnostic tools such as uterine artery Doppler velocimetry have been useful in predicting early PE in major medical centers. These PE risk factors, early predictors and diagnostic tools vary vastly in different regions of the Eastern, Western and Developing world. Further understanding of the differences in the demographic, genetic, dietary and environmental factors among pregnant women in different world regions should help in designing a region-specific cluster of risk factors and predictors of PE, and in turn provide better guidance for region-specific tools for early detection and management of PE.

Association of MTHFR C677T Polymorphism with Preeclampsia in North East of Iran (Khorasan Province)

Background: Preeclampsia (PE) is one of the main causes of fetal and maternal mortality. The analysis of candidate gene polymorphisms can improve our understanding of the mechanisms underlying pathogenesis of PE. Present study is aimed at investigating the association between MTRR c.66A > G, MTHFR c.677C > T, MTHFR c.1298A > C, and MTR c.2756A > G polymorphisms and PE in Iranian women. Methods: About 117 women with history of PE and 103 healthy women with a pregnancy not complicated by PE were selected. The genomic DNA was extracted from peripheral blood. Single-nucleotide polymorphisms were genotyped using Real-Time PCR. Results: There was a significant difference between MTHFR c.677C > T polymorphism with PE (p = 0.045). The frequency of C/T heterozygous genotypes were (58% vs. 36%) in the case and control groups, respectively. There were no statistically significant differences between other genetic polymorphisms. Conclusions: The results indicated that the MTHFR c.677C > T polymorphism may be associated with development of PE in Iranian women.

Proteomic profile of preeclampsia in the first trimester of pregnancy

OBJECTIVE

Preeclampsia (PE) is a leading cause of pregnancy-associated maternal and neonatal morbidity and mortality. Detection of patients at risk before the clinical onset of PE is a priority. Proteomics have become a valuable tool for the discovery of new biomarkers; however, the understanding of the underlying mechanism is necessary. The aim of the study was to determine differences between proteomic serum profiles of PE and normotensive pregnancies using quantitative and qualitative approaches.

STUDY DESIGN

Serum samples from pregnant women were taken at 10-12 weeks of gestation with follow-up to determine PE development. Samples were analyzed using nano 2-D liquid chromatography UPLC and qTOF-MS/MS.

RESULTS

A total of 136 women were recruited, of which eight (5.9%) developed PE, and eight normotensive were randomly selected as a control group for comparison. A different profile was obtained between groups. Nine proteins showed quantitative differences with fold-change over 1.5: PRRC2C (217.02), HEATR5A (179.46), ATP6 (162.38), PRRC2B (83.09), RBM25 (5.36), NUP205 (3.38), HLA-I (2.27), ZC3H13 (2.15), and SREK1 (1.66); and two under 0.66: Importin-4 (0.55) and Cytochrome b (0.26). Using bilateral Fisher's exact test for the qualitative approach, LRRK1 had statistical significance (p = .044), while PRRC2B (p = .121), PRRC2C (p = .134), and NUP205 (p = .134) showed a tendency to be present in PE.

CONCLUSION

The found proteins have plausibility with the early pathophysiological events that have been associated with this pathology. Further studies should be performed to confirm these findings and elucidate their specific roles.

MiR-384 inhibits proliferation and migration of trophoblast cells via targeting PTBP3

Preeclampsia (PE) is one type of hypertension during pregnancy that seriously threatens maternal and infant health. Trophoblast dysfunction, such as decreased proliferation and migration, is closely related to the occurrence and development of PE. MicroRNAs (miRNAs) have been proven to play an important role in many diseases, including PE. miR-384 was reported to play a regulatory role in promoting cell apoptosis and inhibiting proliferation, migration and invasion in a variety of tumors. Previously, we found that miR-384 is upregulated in the placenta and plasma in the context of PE. In this study, we elucidated the function of miR-384 in the trophoblast cell line HTR-8/SVneo and the trophoblastic tumor cell line JEG-3. Cell proliferation and migration were inhibited by miR-384 overexpression but promoted by miR-384 downregulation. Subsequently, polypyrimidine tract-binding protein 3(PTBP3) was found to be a direct target gene of miR-384. PTBP3 was downregulated in placental tissues from PE patients, and a negative correlation was found between PTBP3 and miR-384. Our results suggest that the miR-384/PTBP3 axis plays an important role in regulating trophoblast function during the progression of PE, and these data provide novel insight into the molecular pathogenesis of this disorder.

Comparison of the transcriptional profile in the decidua of early-onset and late-onset pre-eclampsia

AIM

To compare early-onset pre-eclampsia (EOPE) and late-onset pre-eclampsia (LOPE) and provide insight into the pathophysiology of pre-eclampsia (PE).

METHODS

Our recent work compared the transcriptomics in decidua of EOPE, LOPE and normal pregnancies (NP).

RESULTS

We found there are a significant number of genes uniquely expressed in the decidua of EOPE and LOPE comparing with NP. Moreover, EOPE and LOPE have their distinct profiles. Unique EOPE-associated genes were mainly involved in apoptosis related pathways such as 'apoptosis' and 'Ras signaling pathway'. PIK3CB and BCL-2 are the core regulatory genes in EOPE decidua, their abnormal expression caused decidual abnormal apoptosis which is relevant to the pathogenesis of EOPE. Whereas, LOPE is a more complicated entity which has more special LOPE-associated genes involved in decidua differentiation, especially in 'gap junction pathway', 'vascular smooth muscle contraction' and 'long-term depression'. PIK3CB, FLT1, CBLC and ITGA7 are the core regulatory genes differentially expressed in EOPE decidua comparing with LOPE.

CONCLUSION

In brief, the different decidual transcriptomics of EOPE and LOPE may correlate with their different etiology. These findings highlight the complex pathophysiology of PE and provide potential targets for a new treatment strategy in patients with PE.

An Insight into the Angiogenic and Lymphatic Interplay in Pre-eclampsia Comorbid with HIV Infection

PURPOSE OF REVIEW

To provide insight on the imbalance of angiogenic and lymphangiogenic factors in pre-eclampsia, as well as highlight polymorphism in genes related to angiogenesis and lymphangiogenesis.

RECENT FINDINGS

The pregnancy-specific disorder pre-eclampsia is diagnosed by the presence of hypertension with/without proteinuria, after 20 weeks of gestation. The pathogenesis of pre-eclampsia remains ambiguous, but research over the years has identified an imbalance in maternal and foetal factors. Familial predisposition and gene variation are also linked to pre-eclampsia development. The sFlt-1/PIGF ratio has attracted great attention over the years; more recently several researchers have reported that a sFlt-1/PIGF ratio of ≤ 38 can be used to predict short-term absence of pre-eclampsia. This ratio has the potential to prevent adverse pregnancy outcomes and reduce healthcare costs significantly. Genome-wide studies have additionally identified variation in the foetal gene near Flt-1. The development of preeclampsia is not limited to the maternal interface, but foetal involvement as well as genetic interplay is associated with the disorder.

Oxidative stress in pregnancy complicated by preeclampsia

Preeclampsia is a multisystemic disorder of pregnancy that causes perinatal morbidity and mortality. Studies published in the last decade have contributed to a better understanding of physiopathogenesis through key mechanisms involved, such as altered immune response, endothelial dysfunction, oxidative stress and systemic inflammatory response, as well as genetic susceptibility. Oxidative stress (OS) plays an important role in the development of preeclampsia, since it alters placental remodeling and placental vascular endothelial dysfunction, resulting in an ischemia/reperfusion injury with an increase in xanthine oxidase activity that produces high levels of reactive oxygen species (ROS). ROS can be generated through many pathways within cells, mitochondria, endoplasmic reticulum (ER) and enzymes such as NADPH oxidase are the most important sources, causing widespread and indiscriminate damage to cells and tissues, which leads to an intravascular inflammatory response and maternal systemic endothelial dysfunction characteristic of this prenatal syndrome. Therefore, the following review aims to identify the main risk factors and the role of OS as a pathophysiological mechanism in the development of preeclampsia.

Pericytes Contribute to Dysfunction in a Human 3D Model of Placental Microvasculature through VEGF-Ang-Tie2 Signaling

Placental vasculopathies are associated with a number of pregnancy-related diseases, including pre-eclampsia (PE)-a leading cause of maternal-fetal morbidity and mortality worldwide. Placental presentations of PE are associated with endothelial dysfunction, reduced vessel perfusion, white blood cell infiltration, and altered production of angiogenic factors within the placenta (a candidate mechanism). Despite maintaining vascular quiescence in other tissues, how pericytes contribute to vascular growth and signaling in the placenta remains unknown. Here, pericytes are hypothesized to play a detrimental role in the pathogenesis of placental vascular growth. A perfusable triculture model is developed, consisting of human endothelial cells, fibroblasts, and pericytes, capable of recapitulating growth and remodeling in a system that mimics inflamed placental microvessels. Placental pericytes are shown to contribute to growth restriction of microvessels over time, an effect that is strongly regulated by vascular endothelial growth factor and Angiopoietin/Tie2 signaling. Furthermore, this model is capable of recapitulating essential processes including tumor necrosis factor alpha (TNFα)-mediated vascular leakage and leukocyte infiltration, both important aspects associated with placental PE. This placental vascular model highlights that an imbalance in endothelial-pericyte crosstalk can play a critical role in the development of vascular pathology and associated diseases.

AP2γ mediated downregulation of lncRNA LINC00511 as a ceRNA suppresses trophoblast invasion by regulating miR-29b-3p/Cyr61 axis

BACKGROUND

Long noncoding RNA LINC00511 has been identified to be aberrant expression and may as a tumor oncogene in various carcinomas. However, the potential role of LINC00511 in the onset of Preeclampsia (PE) pathogenesis remains unexplored.

METHODS

Placental tissues from patients with PE were collected to detect expression levels of LINC00511 by qRT-PCR. Human HTR-8/SVneo trophoblast cell line was cultured, CCK-8 assay, wound healing assay and transwell assay were performed to determine the regulation of trophoblast biological function by LINC00511. Bioinformatics analysis, chromatin immunoprecipitation (ChIP), luciferases reporter assay were performed to verify the regulatory mechanism of LINC00511.

RESULTS

LINC00511 was aberrantly down-regulated in placental tissues of PE patients. Overexpression of LINC00511 promoted trophoblast cell proliferation, migration and invasion. The transcription factor AP2γ directly binds to the promoter region of LINC00511 to activate transcription. In addition, LINC00511 was enriched in cytoplasm and functioned as a molecular spong for miR-29b-3p, antagonizing its ability to repress Cyr61 protein translation.

CONCLUSION

This study demonstrated that AP2γ mediated downregulation of LINC00511 suppresses trophoblast invasion by regulating miR-29b-3p/ Cyr61 axis.

Association among ACE, ESR1 polymorphisms and preeclampsia in Brazilian pregnant women

BACKGROUND

Genetic, immune and environmental factors are involved in preeclampsia (PE) etiopathogenesis. Considering that hypertension and poor placental perfusion are important features in PE, polymorphisms in the angiotensin-converting enzyme (ACE) and estrogen nuclear receptor 1 (ESR1) genes could be involved in the predisposition and/or development of the disease. The aim of this study was to evaluate if polymorphisms in ACE and ESR1 genes were associated with PE occurrence.

MATERIAL AND METHODS

This case-control study included 209 Brazilian pregnant women (107 with severe PE and 102 normotensive controls). The polymorphisms were investigated by polymerase chain reaction (PCR) followed by polyacrylamide gel electrophoresis.

RESULTS

No significant difference between PE versus normotensive pregnant women, as well as early versus late PE, was observed when compared the allelic and genotypic frequencies of insertion/deletion polymorphism in intron 16 of the ACE gene and the single nucleotide polymorphisms (SNPs - rs2234693 and rs9340799) of the ESR1 gene.

CONCLUSION

This pioneer study involving Brazilian women showed no association among the studied polymorphisms and PE, which suggests that ins/del ACE and SNPs ESR1 do not contribute to this disease occurrence in Brazil.

Genetic Variants in Preeclampsia: Lessons From Studies in Latin-American Populations

Placental vascularization is a tightly regulated physiological process in which the maternal immune system plays a fundamental role. Vascularization of the maternal-placental interface involves a wide range of mechanisms primarily orchestrated by the fetal extravillous trophoblast and maternal immune cells. In a healthy pregnancy, an immune cross-talk between the mother and fetal cells results in the secretion of immunomodulatory mediators, apoptosis of specific cells, cellular differentiation/proliferation, angiogenesis, and vasculogenesis, altogether favoring a suitable microenvironment for the developing embryo. In the context of vasculopathy underlying common pregnancy disorders, it is believed that inefficient invasion of extravillous trophoblast cells in the endometrium leads to a poor placental blood supply, which, in turn, leads to decreased secretion of angiogenic factors, hypoxia, and inflammation commonly associated with preterm delivery, intrauterine growth restriction, and preeclampsia. In this review, we will focus on studies published by Latin American research groups, providing an extensive review of the role of genetic variants from candidate genes involved in a broad spectrum of biological processes underlying the pathophysiology of preeclampsia. In addition, we will discuss how these studies contribute to fill gaps in the current understanding of preeclampsia. Finally, we discuss some trending topics from important fields associated with pregnancy vascular disorders (e.g., epigenetics, transplantation biology, and non-coding RNAs) and underscore their possible implications in the pathophysiology of preeclampsia. As a result, these efforts are expected to give an overview of the extent of scientific research produced in Latin America and encourage multicentric collaborations by highlighted regional research groups involved in preeclampsia investigation.

An embryo-fetal development toxicity study with dimethylaminoethyl ginkgolide B in rats and rabbits

Ginkgo biloba (a herbal product) has long been used in traditional Chinese medicine to treat cerebrovascular and cardiovascular diseases. Ginkgolide B is one of the important pharmacologically active components of Ginkgo biloba. Dimethylaminoethyl ginkgolide B (a novel ginkgolide B derivative) has been developed to overcome the poor water-solubility of natural drugs and to achieve higher bioavailability. This study investigated the potential effects of dimethylaminoethyl ginkgolide B on pregnant dams and embryo-fetal development in Sprague-Dawley rats and New Zealand white rabbits following maternal exposure on gestational day (GD) 6-15 and GD 6-18, respectively. Dimethylaminoethyl ginkgolide B was administered by intravenous injection to pregnant rats (0, 10, 30 and 100 mg kg-1 d-1) and rabbits (0, 6, 18 and 60 mg kg-1 d-1). Maternal toxicity signs, such as lower maternal body weight gain and food consumption, were observed at 100 mg kg-1 d-1 in rats and 60 mg kg-1 d-1 in rabbits. The developmental toxic effects included a decrease in fetal and placental weights, increased incidences of skeletal variations and delay in fetal ossification. Fetal growth and development were affected by dimethylaminoethyl ginkgolide B in the high-dose group in rabbits. The no-observed-adverse-effect level of dimethylaminoethyl ginkgolide B is considered to be 30 mg kg-1 d-1 for rats and 18 mg kg-1 d-1 for rabbits.

Candidate Gene, Genome-Wide Association and Bioinformatic Studies in Pre-eclampsia: a Review

PURPOSE OF REVIEW

Regardless of the familial linkage reported in pre-eclampsia development, understanding the polymorphic genes associated with pre-eclampsia remains limited. Hence, this review aims to outline the main genetic factors that have been investigated in respect to pre-eclampsia development.

RECENT FINDINGS

It is apparent that different genes show significance in varying populations. Notably, it is reported that apolipoprotein-1 gene polymorphisms are associated with pre-eclampsia development in an African-American population, which may be worthwhile to investigate in a Black South African cohort. Despite the research attention that is focused on this surreptitious syndrome, a definitive cause eludes scientists and physicians, alike. Genetic studies can fulfil a dual purpose of suggesting novel hypotheses through genome-wide screening and testing these hypotheses via candidate gene studies. However, publications to date have only presented inconsistent and conflicting results regarding candidate gene analysis.

Integrated Systems Biology Approach Identifies Novel Maternal and Placental Pathways of Preeclampsia

Preeclampsia is a disease of the mother, fetus, and placenta, and the gaps in our understanding of the complex interactions among their respective disease pathways preclude successful treatment and prevention. The placenta has a key role in the pathogenesis of the terminal pathway characterized by exaggerated maternal systemic inflammation, generalized endothelial damage, hypertension, and proteinuria. This sine qua non of preeclampsia may be triggered by distinct underlying mechanisms that occur at early stages of pregnancy and induce different phenotypes. To gain insights into these molecular pathways, we employed a systems biology approach and integrated different "omics," clinical, placental, and functional data from patients with distinct phenotypes of preeclampsia. First trimester maternal blood proteomics uncovered an altered abundance of proteins of the renin-angiotensin and immune systems, complement, and coagulation cascades in patients with term or preterm preeclampsia. Moreover, first trimester maternal blood from preterm preeclamptic patients in vitro dysregulated trophoblastic gene expression. Placental transcriptomics of women with preterm preeclampsia identified distinct gene modules associated with maternal or fetal disease. Placental "virtual" liquid biopsy showed that the dysregulation of these disease gene modules originates during the first trimester. In vitro experiments on hub transcription factors of these gene modules demonstrated that DNA hypermethylation in the regulatory region of ZNF554 leads to gene down-regulation and impaired trophoblast invasion, while BCL6 and ARNT2 up-regulation sensitizes the trophoblast to ischemia, hallmarks of preterm preeclampsia. In summary, our data suggest that there are distinct maternal and placental disease pathways, and their interaction influences the clinical presentation of preeclampsia. The activation of maternal disease pathways can be detected in all phenotypes of preeclampsia earlier and upstream of placental dysfunction, not only downstream as described before, and distinct placental disease pathways are superimposed on these maternal pathways. This is a paradigm shift, which, in agreement with epidemiological studies, warrants for the central pathologic role of preexisting maternal diseases or perturbed maternal-fetal-placental immune interactions in preeclampsia. The description of these novel pathways in the "molecular phase" of preeclampsia and the identification of their hub molecules may enable timely molecular characterization of patients with distinct preeclampsia phenotypes.

Preeclampsia and Related Cardiovascular Risk: Common Genetic Background

PURPOSE OF REVIEW

Preeclampsia (PE) is a hypertensive disorder exclusive for pregnancy. It affects women all over the world and poses a great threat to life, both for mother and child. No definitive treatment exists and placenta delivery comprises the only known cure for PE. One of the most severe complications observed in preeclamptic women is the occurrence of cardiovascular diseases (CVDs) later in life.

RECENT FINDINGS

Both PE and CVDs share some of their pathogenic pathways and gene variations. Thus far, a number of publications have examined those relationships; however, almost all of them focus only on common risk factors. The precise pathomechanism and genetic basis of PE and its associated cardiovascular complications remain unknown. Therefore, the aim of this review is to unify and clarify the current state of knowledge and provide direction for future studies, especially those regarding the genetic aspect.

Maternal serum bisphenol A levels and risk of pre-eclampsia: a nested case-control study

Background

Although recent studies have indicated the potential adverse effects of maternal bisphenol A (BPA) exposure on pregnancy such as increasing the risk of pre-eclampsia, epidemiological evidence is limited. We aimed to evaluate the relationship between maternal BPA exposure and the risk of pre-eclampsia.

Methods

We conducted a nested case-control study among 173 women (74 cases of pre-eclampsia and 99 controls). BPA concentrations were measured using liquid chromatography-mass spectrometry in the maternal serum samples collected during 16-20 gestational weeks. Multivariate logistic models were used to examine the relationship between maternal serum BPA concentrations and the risk of pre-eclampsia.

Results

BPA was detectable (>0.1 µg/l) in 78.6% of the maternal serum samples at three levels: low (<2.24 µg/l), medium (2.24-4.44 µg/l), and high (>4.44 µg/l). BPA concentrations were significantly higher in the serum samples collected from the pre-eclampsia cases than those from controls (median: 3.40 vs. 1.50 µg/l, P < 0.01). With adjustment for maternal age, primiparous and BMI, the odds of developing pre-eclampsia were significantly elevated in subjects with high serum BPA levels compared with those with low levels (adjusted OR = 16.46, 95%CI = 5.42-49.85) regardless of subcategories of pre-eclampsia including severity and onset time. Among the pre-eclampsia subjects, the maternal serum concentration of BPA was not different between the early- and late-onset subjects (median: 3.09 vs. 3.50 µg/l, P = 0.57), but surprisingly higher in mild pre-eclampsia subjects compared with severe pre-eclampsia subjects (median: 5.20 vs. 1.80 µg/l, P < 0.01).

Conclusions

These results demonstrated that maternal exposure to high level of BPA could be associated with an increased risk of pre-eclampsia.

The genetic component of preeclampsia: A whole-exome sequencing study

Preeclampsia is a major cause of maternal and perinatal deaths. The aetiology of preeclampsia is largely unknown but a polygenetic component is assumed. To explore this hypothesis, we performed an in-depth whole-exome sequencing study in women with (cases, N = 50) and without (controls, N = 50) preeclampsia. The women were identified in an unselected cohort of 2,545 pregnant women based on data from the Danish National Patient Registry and the Medical Birth Registry. Matching DNA was obtained from a biobank containing excess blood from routine antenatal care visits. Novogene performed the whole-exome sequencing blinded to preeclampsia status. Variants for comparison between cases and controls were filtered in the Ingenuity Variant Analysis software. We applied two different strategies; a disease association panel approach, which included variants in single genes associated with established clinical risk factors for preeclampsia, and a gene panel approach, which included biological pathways harbouring genes previously reported to be associated with preeclampsia. Variant variability was compared in cases and controls at the level of biological processes, signalling pathways, and in single genes. Regardless of the applied strategy and the level of variability examined, we consistently found positive correlations between variant numbers in cases and controls (all R²s>0.88). Contrary to what was expected, cases carried fewer variants in biological processes and signalling pathways than controls (all p-values ≤0.02). In conclusion, our findings challenge the hypothesis of a polygenetic aetiology for preeclampsia with a common network of susceptibility genes. The greater genetic diversity among controls may suggest a protective role of genetic diversity against the development of preeclampsia.