Genetic Predisposition to Adverse Neurodevelopmental Outcome of Extremely Low Birth Weight Infants

OBJECTIVE

 This study aimed to evaluate whether there are genetic variants associated with adverse neurodevelopmental outcomes in extremely low birth weight (ELBW) infants.

STUDY DESIGN

 We conducted a candidate gene association study in two well-defined cohorts of ELBW infants (<1,000 g). One cohort was for discovery and the other for replication. The discovery case-control analysis utilized anonymized DNA samples and evaluated 1,614 single-nucleotide polymorphisms (SNPs) in 145 genes concentrated in inflammation, angiogenesis, brain development, and oxidation pathways. Cases were children who died by age one or who were diagnosed with cerebral palsy (CP) or neurodevelopmental delay (Bayley II mental developmental index [MDI] or psychomotor developmental index [PDI] < 70) by 18 to 22 months. Controls were survivors with normal neurodevelopment. We assessed significant epidemiological variables and SNPs associated with the combined outcome of CP or death, CP, mental delay (MDI < 70) and motor delay (PDI < 70). Multivariable analyses adjusted for gestational age at birth, small for gestational age, sex, antenatal corticosteroids, multiple gestation, racial admixture, and multiple comparisons. SNPs associated with adverse neurodevelopmental outcomes with p < 0.01 were selected for validation in the replication cohort. Successful replication was defined as p < 0.05 in the replication cohort.

RESULTS

 Of 1,013 infants analyzed (452 cases, 561 controls) in the discovery cohort, 917 were successfully genotyped for >90% of SNPs and passed quality metrics. After adjusting for covariates, 26 SNPs with p < 0.01 for one or more outcomes were selected for replication cohort validation, which included 362 infants (170 cases and 192 controls). A variant in SERPINE1, which encodes plasminogen activator inhibitor (PAI1), was associated with the combined outcome of CP or death in the discovery analysis (p = 4.1 × 10-4) and was significantly associated with CP or death in the replication cohort (adjusted odd ratio: 0.4; 95% confidence interval: 0.2-1.0; p = 0.039).

CONCLUSION

 A genetic variant in SERPINE1, involved in inflammation and coagulation, is associated with CP or death among ELBW infants.

KEY POINTS

· Early preterm and ELBW infants have dramatically increased risks of CP and developmental delay.. · A genetic variant in SERPINE1 is associated with CP or death among ELBW infants.. · The SERPINE1 gene encodes the serine protease inhibitor plasminogen activator inhibitor..

Investigation of the linkage between TNF-alfa rs1800629 polymorphism and preeclampsia risk: A meta-analysis

BACKGROUND

Preeclampsia is a serious medical condition that significantly affects expectant mothers. Growing research showed an inconsistent association between TNF-alfa rs1800629 polymorphism and preeclampsia. The current meta-analysis was aimed at examining the potential impact of rs1800629 variant on preeclampsia.

METHODS

The Cochrane Library, Google Scholar, PubMed, EMBASE, Web of Science, and other databases were searched extensively to locate and select articles up to October 30, 2023. The PRISMA 2020 recommendations were followed to perform this study. Data analysis was done by using Comprehensive Meta analysis (v 3).

RESULTS

We have included 32 articles containing 35 studies with 3,883 patients and 5,821 controls for qualitative and quantitative data analysis. We found a strong relationship between rs1800629 variant with the increased preeclampsia risk in co-dominant model 1 (OR = 1.33, p = 0.019), co-dominant model 2 (OR = 1.43, p = 0.014), dominant model (OR = 1.25, p = 0.044), over-dominant model (OR = 1.31, p = 0.021), and allelic model (OR = 1.24, p = 0.018). This study also revealed a significantly higher risk among the Asian population in the dominant (OR = 2.31, p = 0.036) and allelic model (OR = 2.02, p = 0.028). For the Caucasian population, an increased association between the rs1800629 variant and preeclampsia risk was reported in co-dominant model 1 (OR = 1.37, p = 0.011), co-dominant model 2 (OR = 1.77, p = 0.007), dominant model (OR = 1.32, p = 0.030), recessive (OR = 1.50, p = 0.047), over-dominant (OR = 1.34, p = 0.009), and allelic model (OR = 1.32, p = 0.004). Though our study showed the protective link of the TNF-alfa polymorphism to the preeclampsia risk among the Black population, no significant outcomes were observed in any genetic models (p > 0.05).

CONCLUSION

Overall, the present meta-analysis explored a consistent linkage of the TNF-alfa rs1800629 variant to the preeclampsia risk in different ethnic groups. Additional research is required to confirm the precise relationship between the rs1800629 variant and preeclampsia risk.

Hemostasis in Pre-Eclamptic Women and Their Offspring: Current Knowledge and Hemostasis Assessment with Viscoelastic Tests

Pre-eclampsia (PE) is a placenta-mediated disease and remains a major cause of maternal and neonatal mortality and morbidity. As PE develops, normal pregnancy's hypercoagulable balance is disrupted, leading to platelet hyperactivation, excessive pathological hypercoagulability, and perturbed fibrinolysis. This narrative review aims to summarize the current knowledge regarding hemostasis in PE compared with healthy gestation and the potential effects of maternal PE on neonatal hemostasis. Finally, it aims to discuss hemostasis assessments for normal pregnancies and PE, emphasizing the role of viscoelastic tests, namely, thromboelastography (TEG) and thromboelastometry (ROTEM), for monitoring PE-associated hemostatic alterations. The use of TEG/ROTEM for assessing the hemostatic profile of PE women has been little considered, even though conventional coagulation tests (CCTs) have not helped to monitor hemostasis in this population. Compared with normal pregnancy, TEG/ROTEM in PE reveals an excessive hypercoagulability analogous with the severity of the disease, characterized by higher-stability fibrin clots. The TEG/ROTEM parameters can reflect PE severity and may be used for monitoring and as predictive markers for the disease.

Pertinence between risk of preeclampsia and the renin-angiotensin-aldosterone system (RAAS) gene polymorphisms: an updated meta-analysis based on 73 studies

The aetiological mechanism of preeclampsia (PE) is unclear exactly, so we attempted to investigate the association between susceptibility to preeclampsia and renin-angiotensin-aldosterone system (RAAS) gene polymorphisms to explore the aetiology in terms of genetics. A systematic search was performed in electronic databases to identify relevant studies. Eventually 73 studies were enrolled, odds ratios were generated by 5 genetic models. In overall analysis, significant associations were detected for AGT M235T, AT1R A1166C and CYP11B2 C344T whereas negative correlation was shown for AGT T174M. As stratified by race and geography, AGT 235T allele and AT1R 1166C allele increased preeclampsia risk and AGT T174M was justified uncorrelated with preeclampsia. Our meta-analysis illustrated that AGT 235T allele and AT1R 1166C allele increased and CYP11B2 344T allele decreased preeclampsia risk while AGT T174M polymorphism did not change preeclampsia risk. Hence, pregnant women carrying high-risk genotypes need strengthened management to prevent and early identification of preeclampsia.

Association between genetic polymorphisms of leptin receptor and preeclampsia in Chinese women

OBJECTIVE

Leptin signaling plays an important role in regulating metabolism and reproduction. In the present study, we investigated the relationship between polymorphisms of leptin receptor (LEPR) gene A223G and A668G and preeclampsia (PE) and evaluated influences of genotypes on clinical, metabolic, and oxidative stress indices in Chinese women.

METHODS

This is a case-control study including 322 patients with PE and 1295 healthy pregnant women. The two polymorphisms were genotyped by polymerase chain reaction-restriction fragments length polymorphism method. Clinical and biochemical parameters were analyzed.

RESULTS

The frequencies of the AA + AG genotypes (28.6% vs. 36.1%) and A allele (14.9% vs. 19.8%) of LEPR A223G polymorphism, and those of the AA + AG genotypes (17.7% vs. 24.6%) and A allele (9.0% vs. 12.9%) of LEPR A668G polymorphism were significantly lower in the PE group than those in the control group. The 223A and 668A alleles were protective factors against PE in the regression model, which included age and delivery body mass index as covariates (OR = 0.684, 95% CI: 0.506-0.926, p = .014; OR = 0.650, 95% CI: 0.456-0.927, p = .017, respectively). When the 668GG/223GG combined genotype served as the reference category, the 668A/223A combined allele had further enhanced the protective effect on PE (OR = 0.558, 95% CI: 0.374-0.833, p = .004). Patients possessing the LEPR 223A allele had higher total antioxidant capacity and lower oxidative stress index (p < .05), while those with the LEPR 668A allele had higher high-density lipoprotein cholesterol levels (p = .045) compared with those carrying the corresponding GG genotype.

CONCLUSIONS

The 223A and 668A alleles of LEPR polymorphisms are genetic protective factors for PE in Chinese women. The two alleles may exert a beneficial effect on oxidative stress and lipid metabolism in patients.

Candidate genes related to acute cerebral circulatory disorders in Preeclampsia in the Kazakh Population

BACKGROUND

The purpose of this study is to conduct a comparative analysis of the population frequencies of alleles and genotypes of polymorphic variants of coagulation and fibrinolysis genes SERPINE1 rs1799889, ITGA2 rs1126643, THBD rs1042580, FII rs1799963, FV rs6025, FVII rs6046, angiogenesis and endothelial dysfunction PGF rs12411, FLT1 rs4769612, KDR rs2071559, ACE rs4340, GWAS associated with the development of acute cerebral circulatory disorders in preeclampsia, in an ethnically homogeneous population of Kazakhs with previously studied populations of the world.

METHODS

The genomic database was analysed based on the results of genotyping of 1800 conditionally healthy individuals of Kazakh nationality ∼2.5 million SNPs using OmniChip 2.5 M Illumina chips at the DECODE Iceland Genomic Center as part of the joint implementation of the project "Genetic Studies of Preeclampsia in Populations of Central Asia and Europe" (InterPregGen) within the 7th Framework Programme of the European Commission under Grant Agreement No. 282540.

RESULT

The study discovered a significantly higher population frequency of carrying the unfavorable rs1126643 allele of the ITGA2 gene polymorphism when compared with European populations. The population frequencies of carrying minor alleles of the SERPINE1 (rs179988) and KDR (rs2071559) genes in the Kazakh population were significantly lower when compared with the previously studied populations of Europe and Asia. An intermediate frequency of unfavorable minor alleles between European and Asian populations was found in Kazakhs for gene polymorphisms: FV rs6025, PGF rs12411, and ACE rs4340. The genomic analysis determined the choice of polymorphisms for their further replicative genotyping in patients with ACCD in PE in the Kazakh population.

CONCLUSION

The obtained results will serve as a basis for the development of effective methods of early diagnosis and treatment of PE in pregnant women, carriers of unfavorable genotypes.

Vitamin D receptor gene polymorphism in Madura pregnant women with hypertension: a case control study

Background

Genetic factors are important considerations in the etiology of preeclampsia and gestational hypertension. Several previous studies have shown an association of Vitamin D receptor (VDR) gene polymorphisms with hypertension in pregnancy. However, the number of studies is still very limited and the results differ from one another.

Aim of the study

This study aimed to analyze the polymorphisms of rs2228570 and rs731236 of the VDR gene in subjects with hypertension and non-hypertension in pregnancy in Madura ethnicity.

Subjects and methods

The researchers conducted tests for two polymorphisms in the VDR gene among 210 subjects consisting of 105 pregnant women with hypertension and 105 non-hypertension pregnant women from Madura ethnicity. The rs2228570 (T>C) and rs731236 (C>T) polymorphisms were detected by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism. All data were analyzed by T-tests and Chi-Square tests.

Results

The TT genotype frequency of rs2228570 (15.2%) in the hypertension group was higher than in the control group (6.7%) (p = 0.047). Subjects with the TT genotype at rs2228570 showed a 3.048 times greater risk of developing hypertension than the CC genotype (OR = 3.048: 1.135–8.183, p = 0.023). The T allele frequency of rs2228570 (40.5%) in the hypertension group was higher than in the control group (30.5%) (p = 0.032). Subjects with the T allele had 1.551 times greater risk of developing hypertension. There was no significant difference in genotype and allele of rs731236 between hypertension subjects and controls.

Conclusion

The TT genotype and T allele of rs2228570 in the hypertension group were risk factors for hypertension in this study. While the TT genotype and T allele at rs731236 were not risk factors for hypertension in pregnancy. Genotyping of VDR gene polymorphisms in pregnant women is expected to be useful in strategies for treating hypertension in pregnancy.

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.

The abnormal expression of Tim-3 is involved in the regulation of myeloid-derived suppressor cells and its correlation with preeclampsia

INTRODUCTION

Maternal immune system tolerance to the semi-allogeneic fetus is critical to a successful pregnancy. We previously reported that myeloid-derived suppressor cells (MDSC) was associated with maternal immune imbalance. T cell immunoglobulin and mucin-containing protein 3 (Tim-3)/Galectin-9 (Gal-9) pathway modulates function of various immune cells in maternal-fetal interface. However, the regulatory effects of Tim-3/Gal-9 signaling on MDSCs and its role in preeclampsia (PE) remain unclear.

METHODS

In the current study we investigated the expression of Tim-3 on MDSC in preeclampsia (PE) patients to further explore the pathogenesis of PE.

RESULTS

The proportion of Tim-3⁺ M-MDSC (monocytic MDSC) cells was higher in PE patients than in healthy control. Meanwhile, the protein expression of Gal-9, as the ligand of Tim-3, was increased in placenta of PE patients. M-MDSC also expressed a higher level of interferon-γ (IFN-γ) and a lower level of transforming growth factor-β (TGF-β) in PE. Furthermore, our study suggested that blocking Tim-3 could attenuate the inhibitory function of MDSC.

DISCUSSION

The abnormal expression of Tim-3 on MDSC might be involved in the pathogenesis of PE, and could be a marker to evaluate the immune function in PE.

Cardiovascular events following pregnancy complicated by pre-eclampsia with emphasis on comparison between early- and late-onset forms: systematic review and meta-analysis

OBJECTIVE

To elucidate whether pre-eclampsia (PE) and the gestational age at onset of the disease (early- vs late-onset PE) have an impact on the risk of long-term maternal cardiovascular complications.

METHODS

MEDLINE, EMBASE and Scopus databases were searched until 15 April 2020 for studies evaluating the incidence of cardiovascular events in women with a history of PE, utilizing combinations of the relevant MeSH terms, keywords and word variants for 'pre-eclampsia', 'cardiovascular disease' and 'outcome'. Inclusion criteria were cohort or case-control design, inclusion of women with a diagnosis of PE at the time of the first pregnancy, and sufficient data to compare each outcome in women with a history of PE vs women with previous normal pregnancy and/or in women with a history of early- vs late-onset PE. The primary outcome was a composite score of maternal cardiovascular morbidity and mortality, including cardiovascular death, major cardiovascular and cerebrovascular events, hypertension, need for antihypertensive therapy, Type-2 diabetes mellitus, dyslipidemia and metabolic syndrome. Secondary outcomes were the individual components of the primary outcome analyzed separately. Data were combined using a random-effects generic inverse variance approach. MOOSE guidelines and the PRISMA statement were followed.

RESULTS

Seventy-three studies were included. Women with a history of PE, compared to those with previous normotensive pregnancy, had a higher risk of composite adverse cardiovascular outcome (odds ratio (OR), 2.05 (95% CI, 1.9-2.3)), cardiovascular death (OR, 2.18 (95% CI, 1.8-2.7)), major cardiovascular events (OR, 1.80 (95% CI, 1.6-2.0)), hypertension (OR, 3.93 (95% CI, 3.1-5.0)), need for antihypertensive medication (OR, 4.44 (95% CI, 2.4-8.2)), dyslipidemia (OR, 1.32 (95% CI, 1.3-1.4)), Type-2 diabetes (OR, 2.14 (95% CI, 1.5-3.0)), abnormal renal function (OR, 3.37 (95% CI, 2.3-5.0)) and metabolic syndrome (OR, 4.30 (95% CI, 2.6-7.1)). Importantly, the strength of the associations persisted when considering the interval (< 1, 1-10 or > 10 years) from PE to the occurrence of these outcomes. When stratifying the analysis according to gestational age at onset of PE, women with previous early-onset PE, compared to those with previous late-onset PE, were at higher risk of composite adverse cardiovascular outcome (OR, 1.75 (95% CI, 1.0-3.0)), major cardiovascular events (OR, 5.63 (95% CI, 1.5-21.4)), hypertension (OR, 1.48 (95% CI, 1.3-1.7)), dyslipidemia (OR, 1.51 (95% CI, 1.3-1.8)), abnormal renal function (OR, 1.52 (95% CI, 1.1-2.2)) and metabolic syndrome (OR, 1.66 (95% CI, 1.1-2.5).

CONCLUSIONS

Both early- and late-onset PE represent risk factors for maternal adverse cardiovascular events later in life. Early-onset PE is associated with a higher burden of cardiovascular morbidity and mortality compared to late-onset PE. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Genetic markers for preeclampsia in Peruvian women

BACKGROUND

Preeclampsia is a multiorgan disorder associated with maternal and perinatal morbi-mortality. In Peru, incidence is 10% and accounts for 22% of maternal deaths. Genome and genetic epidemiological studies have found an association between preeclampsia and genetic polymorphisms.

OBJECTIVE

To determine the association of the vascular endothelial growth factor (VEGF) +936 C/T and +405 G/C, interleukine-6 (IL-6) -174 G/C, IL-1β-511 C/T, Apo A-1-75 G/A, Apo B-100 2488 C/T (Xbal) polymorphisms with preeclampsia in pregnant Peruvian women.

METHODS

Were included preeclamptic and healthy (control) pregnant women. Maternal blood samples were subjected to DNA extraction, and molecular genetic analysis was conducted using the PCR-RFLP technique and following a specific protocol for each gene. Allele and genotypic frequencies in the cases and controls were compared.

RESULTS

No association was found between the VEGF+936C/T and VEGF+405 polymorphisms and preeclampsia. The frequencies of the GG genotypes and the G allele of the -174 G/C polymorphism in the IL6 gene in preeclamptic and controls showed significant differences, with higher frequencies in cases. For the -511 C/T polymorphism of the IL-1β gene, no significant differences were found in the frequencies of TT genotypes compared with CT+CC. The genotypes and alleles of the Apo-A1-75 G/A and Apo-B100 Xbal variants showed no significant differences between cases and controls.

CONCLUSION

No association was found between the studied genetic markers and preeclampsia. However, in the -174G/C polymorphism of the IL-6 gene, significant differences were found mainly in the GG genotype and G allele.

Maternal serum Apelin 13 and APLN gene promoter variant -1860T > C in preeclampsia

OBJECTIVE

To evaluate the apelin (APLN) -1860 T > C (rs56204867) polymorphism and maternal serum apelin 13 levels in preeclampsia and its association with blood pressure.

METHODS

This case-control study was conducted in department of Biochemistry, Sri Devaraj Urs Medical College, Karnataka, India. A total of 181 subjects were enrolled in the study from department of Department of Obstetrics and Gynecology. The recruited women were grouped as: Group-I (n = 91) cases with preeclampsia and Group-II (n = 90) normotensive healthy pregnant women as controls. Under aseptic conditions, the collected 5 mL blood was distributed for serum separation (3 mL) and genetic analysis (2 mL). Serum was stored at -80 °C after centrifugation at 3000 rpm for 10 min. The collected five mL urine sample was used for urinary protein analysis by dipstick method. The APLN gene -1860 T > C polymorphism and Apelin 13 levels were analyzed by molecular methods and ELISA technique respectively. Birth weight and demographic details were recorded.

RESULTS

In the present study, no significant difference was observed for mean gestational age and maternal age. Systolic (158.7 ± 14.0 mmHg) and diastolic (104.9 ± 10.7 mmHg) blood pressure, and mean arterial pressure (MAP) (123.0 ± 11.1 mmHg) (p-value .001) were significantly increased in preeclamptic women compared with healthy pregnant women. Birth weight (2.4 ± 0.5 kg) (p-value .001) was significantly decreased in babies born to preeclamptic mothers. Birth weights were also expressed in centiles, according to Fenton Chart. Number of small for gestational age (SGA) babies were more in preeclampsia (n = 55) than healthy pregnant women (n = 28). Mean maternal serum apelin 13 (239.4 ± 126.3 pg/mL) (p-value .001) concentrations were significantly lower in preeclampsia compared with healthy controls. Maternal serum apelin 13 concentration in preeclampsia was negatively correlated with systolic blood pressure (r = -0.235), diastolic blood pressure (r= -0.172) and mean arterial pressure (r = -0. 206). However, maternal serum apelin 13 levels showed insignificant positive correlation with age, gestational age and birth weight. The genotype and allele frequencies of APLN gene were found significant between study groups as in preeclampsia (χ² = 11.69; df = 2; p = .0028 and χ2 = 14.27; df = 1; p = .00013 respectively). CC genotype and C allele of APLN - 1860 T > C site was high in preeclampsia.

CONCLUSION

Study concludes that preeclamptic women have low level of serum apelin 13 and -1860 T > C polymorphism at APLN gene promoter site with increased allelic frequency of CC genotype and C allele compared to normotensive pregnant women. And this evidence may link to cardiac complications in preeclamptic women after delivery in later stage.

I/D Polymorphism Gene ACE and Risk of Preeclampsia in Women with Gestational Diabetes Mellitus

Preeclampsia (PE) and gestational diabetes mellitus (GDM) are the most common complications of pregnancy, which result in adverse outcomes for the mother and the fetus. GDM is regarded as a separate independent risk factor for PE development, as evidenced by a higher preeclampsia rate in gestational diabetes mellitus than in the general population. The role the endothelial cell dysfunction plays is considered to be the most reasonable one in the origin of these diseases. The activity of plasma and tissue angiotensin converting enzyme (ACE) is believed to be genetically controlled. The available data suggests that increased ACE activity due to deletion (D)/insertion (I) in the 16th intron of ACE gene, which is called ACE gene I/D polymorphism, is associated with preeclampsia and varies depending on the studied population and the geography. We did not find any literature data that estimates the influence of ACE gene I/D polymorphism on PE rate in pregnant women with GDM. Therefore, the present study aimed to investigate a relationship between ACE gene I/D polymorphism and preeclampsia development in the case of GDM in the Russian population. The study used the genomic DNA derived by phenol-chloroform extraction method from venous blood samples in 137 pregnant women, including samples of 74 women with GDM accompanied with PE and the blood samples of 63 women with GDM w/o preeclampsia. Genotyping of insertion/deletion in the I/D region (16 intron of АСЕ gene) was conducted by real-time PCR using the TaqMan competing probe technology. The particular features in the frequency array of alleles and genotypes of the ACE gen I/D polymorphism under review, as associated with preeclampsia development risk in pregnant women with GDM, were identified. The acquired data testify to the need to further study of ACE gene I/D region polymorphism association in a large patient sample taking into account the PE and GDM risk factors estimated in the clinical practice.

Integrated microarray analysis of key genes and a miRNA‑mRNA regulatory network of early‑onset preeclampsia

Early‑onset preeclampsia (EOPE) is a serious threat to maternal and foetal health. The present study aimed to identify potential biomarkers and targets for the treatment of EOPE. Expression profiles of placenta from patients with EOPE and healthy controls (GSE103542, GSE74341 and GSE44711) were downloaded from the Gene Expression Omnibus database. Integrated analysis revealed 246 genes and 28 microRNAs (miRNAs) that were differentially expressed between patients with EOPE and healthy controls. Differentially expressed genes (DEGs) were primarily enriched in 'biological processes', such as 'cell adhesion', 'female pregnancy', 'extracellular matrix organization' and 'response to hypoxia'. Significant pathways associated with DEGs primarily included 'focal adhesion', 'ECM‑receptor interaction', 'PI3K‑Akt signaling' and 'ovarian steroidogenesis'. A Protein‑Protein Interaction network of DEGs was constructed using the Search Tool for the Retrieval of Interacting Genes/Proteins online database, and epidermal growth factor receptor, collagen α‑1(I) chain, secreted phosphoprotein 1, leptin (LEP), collagen α‑2(I) chain (COL1A2), plasminogen activator inhibitor 1 (SERPINE1), Thy‑1 membrane glycoprotein, bone morphogenetic protein 4, vascular cell adhesion protein 1 and matrix metallopeptidase 1 were identified as hub genes. The alterations of hsa‑miR‑937, hsa‑miR‑148b*, hsa‑miR‑3907, hsa‑miR‑367*, COL1A2, LEP and SERPINE1 in placenta were validated using our local samples. Our research showed that the expression of hsa‑miR‑937, hsa‑miR‑1486*, hsa‑miR‑3907, hsa‑miR‑367* and hub genes in the placenta were closely associated with the pathophysiology of EOPE. hsa‑miR‑937, hsa‑miR‑1486*, hsa‑miR‑3907, hsa‑miR‑367* and hub genes could serve as biomarkers for diagnosis and as potential targets for the treatment of EOPE.

Association of Four Missense SNPs with Preeclampsia in Saudi Women

Objective:

The objective of this study was to investigate the association of rs1051740, rs2234922 (in microsomal epoxide hydrolase 1; EPHX1), rs268 (in lipoprotein lipase; LPL) and rs6025 (in Factor V Leiden; F5) genetic variants with the risk of preeclampsia development in Saudi women.

Materials and Methods:

This case–control study recruited 233 Saudi women (94 preeclampsia cases and 139 healthy controls) who visited the Gynecology and Obstetrics Departments of two hospitals in Jeddah, Saudi Arabia, for routine postpregnancy clinical follow-ups. All the women underwent thorough clinical and biochemical investigations conducted according to the standard clinical guidelines. Genotyping of the study participants was done using real-time polymerase chain reaction-based TaqMan allelic discrimination assay. The strength of the association between genetic variants and disease development was assessed using chi-square, odds ratio, 95% confidence interval and multifactor dimensionality reduction tests.

Result:

The minor alleles “G” in rs268 (LPL) and “A” in rs6025 (F5) were absent in Saudi women. The frequencies of rs1051740 and rs2234922 of EPHX1, both in the homozygous and allelic forms, were not significantly different between preeclampsia patients and healthy controls (for all tests, P > 0.05). The multifactor dimensionality reduction analysis also indicated that the interaction between the four studied single-nucleotide polymorphisms (SNPs) had no significant association with preeclampsia risk.

Conclusion:

This study found that none of the studied genetic variants (neither the single SNP nor the SNP–SNP interactions) explain the development of preeclampsia in the Saudi population. These findings not only underscore the disease heterogeneity but also highlight the need to develop population-specific diagnostic genetic biomarkers for preeclampsia.

Preeclampsia Is a Syndrome with a Cascade of Pathophysiologic Events

This review integrates the currently available information on the molecular, cellular, and systemic mechanisms involved in the pathophysiology of preeclampsia. It highlights that the growth, protection, and promotion of the conceptus requires the modulation of an intact maternal immune system, communication between the mother and fetus, and adaptation of the maternal organic functions. A malfunction in any of these factors, on either side, will result in a failure of the cascade of events required for the normal course of pregnancy. Maladaptive processes, initially aiming to protect the conceptus, fail to anticipate the gradually increasing cardiovascular volume load during the course of pregnancy. As a result, multiple organ dysfunctions install progressively and eventually reach a state where mother and/or fetus are at risk of severe morbidity or even mortality, and where the termination of pregnancy becomes the least harmful solution. The helicopter view on pathophysiologic processes associated with preeclampsia, as presented in this paper, illustrates that the etiology of preeclampsia cannot be reduced to one single mechanism, but is to be considered a cascade of consecutive events, fundamentally not unique to pregnancy.

An insertion-deletion polymorphism in angiotensin-converting enzyme is associated with a reduced risk of preeclampsia: an evidence-based meta-analysis from 44 studies

Objective An updated meta-analysis was performed to evaluate the relationship between an insertion/deletion (I/D) polymorphism in angiotensin-converting enzyme (ACE) and preeclampsia (PE) risk. Methods Pubmed, OVID and China National Knowledge Infrastructure databases were searched. Pooled odds ratios with 95% confidence intervals were calculated using fixed-effects or random-effects model. Results ACE I/D polymorphism decreased the risk of PE in overall analysis. Subgroup analysis revealed a significantly lower risk of PE with ACE I/D polymorphism in Asians, Caucasians. The decreased risk was also found in severe PE and early-onset PE. Conclusion ACE I/D polymorphism may protect against the development of PE.

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.

Relationship between polymorphisms of CXCL3 gene and preeclampsia

Background: Preeclampsia (PE), a pregnancy-specific disease, is a main cause of maternal and perinatal mortality in the world, the exact pathogenesis of which is still unknown. Recent studies have found it is a disorder caused by multiple factors and genes. Previously, we found a significantly abnormal expression of CXCL3 in plasma and placenta of severe preeclampsia. Here, we intend to explore the association of polymorphisms in CXCL3 gene with preeclampsia susceptibility in women from western China.Methods: Four hundred eighty-one pregnant women were involved in this case-control study, including 83 early-onset severe preeclampsia cases, 114 late-onset severe preeclampsia cases, 41 mild preeclampsia cases and 243 normal pregnancies. The rs370655 variant in CXCL3 was detected by the method of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).Results: No significantly reduced risk of preeclampsia is observed in the rs370655 AA genotype compared with other genotypes (AG versus AA: OR = .82, 95%CI = .54-1.26; GG versus AA: OR = .95, 95%CI = .56-1.61). After subgroup analysis, there are still no significant differences among various genotypes in the mild preeclampsia, early-onset severe preeclampsia and late-onset sever preeclampsia.Conclusion: Our study suggests that rs370655 polymorphism in CXCL3 gene may be not the risk factor of preeclampsia, exploring other consequential SNPs in CXCL3 gene may help to predict the preeclampsia.

Genetic Aspects of Preeclampsia: The Role of Polymorphisms in the Genes of the Renin-Angiotensin System

Preeclampsia (PE) is a severe complication that develops in 10% pregnant women. It is the leading cause of maternal and perinatal morbidity and mortality worldwide. The goal of this study was to reveal the frequency of polymorphisms in the angiotensin-converting enzyme gene (ACE I/D) and type 1 angiotensin II receptor gene (AGTR1 A1166C) in pregnant women with severe early- and late-onset PE. A retrospective case-control study of 55 pregnant women with PE (main group) and 30 patients with uncomplicated pregnancy (control group) was conducted. In the main group, we considered two subgroups - early-onset PE (20 patients) and late-onset PE (36 patients). The I/D polymorphism of the ACE gene is associated with the risk of developing PE. The presence of the D allele increases the risk of severe PE. In case of DD genotype, the probability of early-onset PE is 5 times higher than that of the late-onset PE. The analyzed data confirm the involvement of renin-angiotensin system in the PE development. We conclude that the ACE gene polymorphism is a genetic predictor of the early-onset severe PE. Studying the polymorphic loci of the ACE gene makes it possible to use them for the individualized prognosis of the development and course of PE in patients.

Analysis of the Epigenome in Multiplex Pre-eclampsia Families Identifies SORD, DGKI, and ICA1 as Novel Candidate Risk Genes

Pre-eclampsia is a serious heritable disorder that affects 5-8% of pregnancies worldwide. While classical genetic studies have identified several susceptibility genes they do not fully explain the heritability of pre-eclampsia. An additional contribution to risk can be quantified by examining the epigenome, in particular the methylome, which is a representation of interactions between environmental and genetic influences on the phenotype. Current array-based epigenetic studies only examine 2-5% of the methylome. Here, we used whole-genome bisulfite sequencing (WGBS) to determine the entire methylome of 13 individuals from two multiplex pre-eclampsia families, comprising one woman with eclampsia, six women with pre-eclampsia, four women with uncomplicated normotensive pregnancies and two male relatives. The analysis of WGBS profiles using two bioinformatics platforms, BSmooth and Bismark, revealed 18,909 differentially methylated CpGs and 4157 differentially methylated regions (DMRs) concordant in females. The methylation patterns support the involvement of previously reported candidate genes, including COL4A1, SLC2A4, PER3, FLT1, GPI, LCT, DDAH1, TGFB3, DLX5, and LRP1B. Statistical analysis of DMRs revealed three novel genes significantly correlated with pre-eclampsia: sorbitol dehydrogenase (SORD, p = 9.98 × 10^-6), diacylglycerol kinase iota (DGKI, p = 2.52 × 10^-5), and islet cell autoantigen 1 (ICA1, 7.54 × 10^-3), demonstrating the potential of WGBS in families for elucidating the role of epigenome in pre-eclampsia and other complex diseases.

Pregnancy Immunogenetics and Genomics: Implications for Pregnancy-Related Complications and Autoimmune Disease

Pregnancy presents a singular physiological scenario during which the maternal immune system must accommodate the semiallogeneic fetus. Fluctuations between pro- and anti-inflammatory states are required throughout gestation to facilitate uterine tissue remodeling, fetal growth and development, and finally birth. Tolerance for the fetus must be established and maintained without fundamentally compromising the maternal immune system function, so that both the mother and fetus are protected from foreign insults. Here, we review our current understanding of how genetic variation at both maternal and fetal loci affects implantation and placenta formation, thereby determining the likelihood of a successful pregnancy outcome or the development of pregnancy-related complications. We also consider the impact of pregnancy on both the maternal and fetal systemic immune systems and the related implications for modulating ongoing autoimmune diseases and triggering their development.

Upregulation of CD81 in trophoblasts induces an imbalance of Treg/Th17 cells by promoting IL-6 expression in preeclampsia

The disturbance of maternal immune tolerance to a semiallogeneic fetus is recognized as one of the key pathologies of preeclampsia (PE), in which an imbalance between the inflammation-limiting regulatory T cells (Tregs) and the inflammation-mediating Th17 cells plays an essential role. Previously, we reported that the abnormal upregulation of tetraspannin CD81 in trophoblast cells (fetal component) participated in the pathogenesis of PE. However, as one of the potential immune regulatory molecules, whether CD81 induces PE by interfering with the balance of the maternal immune system has not yet been clarified. Thus, we investigated the relationship between the upregulation of CD81 in trophoblast cells and the imbalance of Treg and Th17 cells in mothers. Here, we demonstrated that upregulation of CD81 in trophoblast cells was accompanied by a decrease in Treg cells and an increase in Th17 cells in both the basal plate (placental maternal side) and peripheral blood of patients with PE. In vitro culture of naïve T cells with medium from the CD81-overexpressing trophoblast cell line HTR-8 resulted in enhanced differentiation of T cells into Th17 cells and decreased the formation of Tregs, which was dependent on the paracrine signaling of IL-6 in trophocytes, induced by CD81. In a CD81-induced PE rat model, we found a significant shift of T cell differentiation towards Th17 cells, and administration of IL-6 antibody mitigated the PE phenotype and the imbalance of the Treg/Th17 cells. These results define a vital regulatory cascade involving trophocyte-derived CD81, IL-6, and maternal Treg/Th17 cells in the pathogenesis of PE and suggests new therapeutic approaches based on CD81 and IL-6 downregulation to prevent human PE.

Contribution of angiotensinogen M235T and T174M gene variants and haplotypes to preeclampsia and its severity in (North African) Tunisians

BACKGROUND

Preeclampsia (PE) is a pregnancy-associated hypertensive disorder and a leading cause of maternal and neonatal morbidity and mortality. While its pathogenesis remains ill defined, several candidate genes for PE have been identified, but results remain inconclusive. We investigated the association of the angiotensinogen ( AGT) gene variants M235T and T174M with PE, and we analyzed the contribution of both variants to the severity of PE.

METHODS

This case-control study enrolled 550 Tunisian pregnant women: 272 with PE, of whom 147 presented with mild, and 125 with severe PE, along with 278 unrelated age- and ethnically matched control women. AGT genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

Significantly higher M235T minor allele frequency (MAF) was associated with increased risk of PE ( p < 0.001). Decreased frequency of heterozygous T174M genotype carriers were found in control women ( p = 0.015), suggesting a protective effect of this genotype (odds ratio (95% confidence interval) = 0.51 (0.29-0.89)). Two-locus haplotype analysis demonstrated MM and TT haplotypes to be negatively and positively associated with PE, respectively. MAF of M253T, but not T174M, was higher in the severe PE group, and carrying M235T or T174M minor allele was associated with increased body mass index ( p < 0.001) among unselected PE women.

CONCLUSIONS

AGT M235T and T174M variants contribute to an increased risk of developing PE, and for M235T to PE severity.

Preeclampsia and the challenge of early prediction: reality or utopia? State of art and critical review of literature

Purpose: The challenge to obtain improved predictive tools, able to identify women destined to develop preeclampsia (PE), is raising the interest of researchers for the attractive chance to allow for timely initiation of prophylactic therapy, appropriate antenatal surveillance, and better-targeted research into preventive interventions. We aimed to gather all the evidence reported up to now in scientific literature relating to all prediction tests for PE.Materials and methods: We searched articles on conventional literature platforms from January 1952 to August 2016, using the terms "preeclampsia," "gestational preeclampsia," and "gestational hypertensive disorders" combined with "predictive test" and "risk assessment." Abstracts/titles identified by the search were screened by three investigators.Results: The search identified 203 citations, of which 154 potentially relevant after the initial evaluation. Among these studies, 20 full articles were excluded, therefore, 134 primary studies met the criteria for inclusion and were analyzed.Conclusions: Current evidence suggests that a combination of several features may provide the best predictive accuracy for the identification of PE. Large-scale, multicenter, multiethnic, prospective trials are required to propose an ideal combination of markers for routine screening.

Combination of Genetic Markers and Age Effectively Facilitates the Identification of People with High Risk of Preeclampsia in the Han Chinese Population

Objective

This study aimed to analyze the possible association between known genetic risks and preeclampsia in a Han Chinese population.

Methods

A total of 156 patients with preeclampsia and 286 healthy Han Chinese women were enrolled and genotyped for 27 genetic alleles associated with preeclampsia in different populations. The association between the genotypes of the individual alleles and preeclampsia and the possible interaction among the alleles were analyzed. Finally logistic models were trained with the genotypes of possible alleles contributing to preeclampsia.

Results

Seven alleles were significantly or marginally significantly associated with preeclampsia, which involved six genes (rs4762 in AGT, rs1800896 in IL-10, rs1800629 and rs1799724 in TNFα, rs2070744 in NOS3, rs7412 in APOE, and rs2549782 in ERAP2). A multilocus interaction analysis further disclosed an interaction among seven alleles. A logistic model showing individual or synergetic contribution to preeclampsia could reach ~0.67 preeclampsia prediction accuracy in the Han Chinese population, while integration of age information could improve the performance to ~0.75 accuracy using a fivefold training-testing evaluation strategy.

Conclusions

The genetic factors were closely associated with preeclampsia in the Han Chinese population despite large ethnicity heterogeneity. The genotypes of different alleles also had synergetic interactions.

Exploring traditional and nontraditional roles for thrombomodulin

Thrombomodulin (TM) is an integral component of a multimolecular system, localized primarily to the vascular endothelium, that integrates crucial biological processes and biochemical pathways, including those related to coagulation, innate immunity, inflammation, and cell proliferation. These are designed to protect the host from injury and promote healing. The “traditional” role of TM in hemostasis was determined with its discovery in the 1980s as a ligand for thrombin and a critical cofactor for the major natural anticoagulant protein C system and subsequently for thrombin-mediated activation of the thrombin activatable fibrinolysis inhibitor (also known as procarboxypeptidase B2). Studies in the past 2 decades are redefining TM as a molecule with many properties, exhibited via its multiple domains, through its interacting partners, complex regulated expression, and synthesis by cells other than the endothelium. In this report, we review some of the recently reported diverse properties of TM and how these may impact on our understanding of the pathogenesis of several diseases.

Genetic and non-genetic risk factors for pre-eclampsia: umbrella review of systematic reviews and meta-analyses of observational studies

OBJECTIVE

To summarize evidence from the literature on genetic and non-genetic risk factors associated with pre-eclampsia (PE), assess the presence of statistical bias in the studies and identify risk factors for which there is robust evidence supporting their association with PE.

METHODS

PubMed and ISI Web of Science were searched from inception to October 2016, to identify systematic reviews and meta-analyses of observational studies examining associations between genetic or non-genetic risk factors and PE. For each meta-analysis, the summary-effect size was estimated using random-effects and fixed-effects models, along with 95% CIs and the 95% prediction interval. Between-study heterogeneity was expressed using the I² statistic, and evidence of small-study effects (large studies had significantly more conservative results than smaller studies) and evidence of excess significance bias (too many studies with statistically significant results) were estimated.

RESULTS

Fifty-eight eligible meta-analyses were identified, which included 1466 primary studies and provided data on 130 comparisons of risk factors associated with PE, covering a wide range of comorbid diseases, genetic factors, exposure to environmental agents and biomarkers. Sixty-five (50%) associations had nominally statistically significant findings at P < 0.05, while 16 (12%) were significant at P < 10^-6 . Sixty-five (50%) associations had large or very large heterogeneity. Evidence for small-study effects and excess significance bias was found in 10 (8%) and 26 (20%) associations, respectively. The only non-genetic risk factor with convincing evidence for an association with PE was oocyte donation vs spontaneous conception, which had a summary odds ratio of 4.33 (95% CI, 3.11-6.03), was supported by 2712 cases with small heterogeneity (I²  = 26%) and 95% prediction intervals excluding the null value, and without hints of small-study effects (P for Egger's test > 0.10) or excess of significance (P > 0.05). Of the statistically significant (P < 0.05) genetic risk factors for PE, only PAI-1 4G/5G (recessive model) polymorphism was supported by strong evidence for a contribution to the pathogenesis of PE. Eleven factors (serum iron level, pregnancy-associated plasma protein-A, chronic kidney disease, polycystic ovary syndrome, mental stress, bacterial and viral infections, cigarette smoking, oocyte donation vs assisted reproductive technology, obesity vs normal weight, severe obesity vs normal weight and primiparity) presented highly suggestive evidence for an association with PE.

CONCLUSIONS

A large proportion of meta-analyses of genetic and non-genetic risk factors for PE have caveats that threaten their validity. Oocyte donation vs spontaneous conception and PAI-1 4G/5G polymorphism (recessive model) showed the strongest consistent evidence for an association with risk for PE. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Genetic Approaches in Preeclampsia

Preeclampsia (PE) is a serious hypertensive disorder that affects up to 8% of all pregnancies annually. An established risk factor for PE is family history, clearly demonstrating an underlying genetic component to the disorder. To date, numerous genetic studies, using both the candidate gene and genome-wide approach, have been undertaken to tease out the genetic basis of PE and understand its origins. Such studies have identified some promising candidate genes such as STOX1 and ACVR2A. Nevertheless, researchers face ongoing challenges of replicating these genetic associations in different populations and performing the functional validation of identified genetic variants to determine their causality in the disorder. This chapter will review the genetic approaches used in the study of PE, discuss their limitations and possible confounders, and describe current strategies.

A Family Based Study of Carbon Monoxide and Nitric Oxide Signalling Genes and Preeclampsia

BACKGROUND

Preeclampsia is thought to originate during placentation, with incomplete remodelling and perfusion of the spiral arteries leading to reduced placental vascular capacity. Nitric oxide (NO) and carbon monoxide (CO) are powerful vasodilators that play a role in the placental vascular system. Although family clustering of preeclampsia has been observed, the existing genetic literature is limited by a failure to consider both mother and child.

METHODS

We conducted a nested case-control study within the Norwegian Mother and Child Birth Cohort of 1545 case-pairs and 995 control-pairs from 2540 validated dyads (2011 complete pairs, 529 missing mother or child genotype). We selected 1518 single-nucleotide polymorphisms (SNPs) with minor allele frequency >5% in NO and CO signalling pathways. We used log-linear Poisson regression models and likelihood ratio tests to assess maternal and child effects.

RESULTS

One SNP met criteria for a false discovery rate Q-value <0.05. The child variant, rs12547243 in adenylate cyclase 8 (ADCY8), was associated with an increased risk (relative risk [RR] 1.42, 95% confidence interval [CI] 1.20, 1.69 for AG vs. GG, RR 2.14, 95% CI 1.47, 3.11 for AA vs. GG, Q = 0.03). The maternal variant, rs30593 in PDE1C was associated with a decreased risk for the subtype of preeclampsia accompanied by early delivery (RR 0.45, 95% CI 0.27, 0.75 for TC vs. CC; Q = 0.02). None of the associations were replicated after correction for multiple testing.

CONCLUSIONS

This study uses a novel approach to disentangle maternal and child genotypic effects of NO and CO signalling genes on preeclampsia.

Personalized Therapy Against Preeclampsia by Replenishing Placental Protein 13 (PP13) Targeted to Patients With Impaired PP13 Molecule or Function

Hypertensive disorders affect about one third of all people aged 20 and above, and are treated with anti-hypertensive drugs. Preeclampsia (PE) is one form of such disorders that only develops during pregnancy. It affects ten million pregnant women globally and additionally causes fetal loss and major newborn disabilities. The syndrome's origin is multifactorial, and anti-hypertensive drugs are ineffective in treating it. Biomarkers are helpful for predict its development. Generic drugs, such as low dose aspirin, were proven effective in preventing preterm PE. However, it does not cure the majority of cases and many studies are underway for fighting PE with extended use of additional generic drugs, or through new drug development programs. This review focuses on placental protein 13 (PP13). This protein is only expressed in the placenta. Impaired PP13 DNA structure and/or its reduced mRNA expression leads to lower blood PP13 level that predict a higher risk of developing PE. Two polymorphic PP13 variants have been identified: (1) The promoter PP13 variant with an "A/A" genotype in the -98 position (versus "A/C" or "C/C"). Having the "A/A" genotype is coupled to lower PP13 expression, mainly during placental syncytiotrophoblast differentiation and, if associated with obesity and history of previous preeclampsia, it accurately predicts higher risk for developing the disorder. (2) A thymidine deletion at position 221 causes a frame shift in the open reading frame, and the formation of an early stop codon resulting in the formation of DelT221, a truncated variant of PP13. In pregnant rodents, both short- and long- term replenishment of PP13 causes reversible hypotension and vasodilation of uterine vessels. Long-term exposure is also accompanied by the development of larger placentas and newborns. Also, only w/t PP13 is capable of inducing leukocyte apoptosis, providing maternal immune tolerance to pregnancy. Based on published data, we propose a targeted PP13 therapy to fight PE, and consider the design and conduct of animal studies to explore this hypothesis. Accordingly, a new targeted therapy can be implemented in humans combining prediction and prevention.

CASPASE-8 gene polymorphisms (rs13416436 and rs2037815) are not associated with preeclampsia development in Brazilian women

BACKGROUND

Preeclampsia is responsible for considerable mortality and morbidity of mother and sibling. The etiology of preeclampsia is still unknown. Family studies indicate the involvement of genes located on chromosome 2 in preeclampsia development. Considering the importance of apoptosis and chromosome 2, one promising candidate for the study of the genetic cause of this syndrome is the CASPASE-8 gene, which was chosen as the subject of this study.

OBJECTIVE

The aim of this study was to determine the frequencies of the genotypes for CASP8 gene polymorphisms (rs13416436 and rs2037815) and to associate these with preeclampsia development in Brazilian women.

METHODS

Women with and without preeclampsia were investigated. Accordingly, peripheral blood was collected and DNA extracted, followed by genotyping using Real-time PCR with hydrolysis probe (Taqman^® Life Technologies).

RESULTS

The results showed no association between genotypes and preeclampsia development for both polymorphisms studied (χ²=1.03; p = 0.59, for rs13416436 and χ²=1.06; p = 0.58 for rs2037815).

CONCLUSIONS

It seems that CASP8 gene polymorphisms (rs13416436 and rs2037815) are not important candidates for the development of preeclampsia. Other genes related to the apoptosis process or other polymorphisms in this gene should be studied in order to understand better the etiology of preeclampsia.

Genetic predisposition to elevated levels of C-reactive protein is associated with a decreased risk for preeclampsia

OBJECTIVE

To examine the association between genetic predisposition to elevated C-reactive protein (CRP)and risk for preeclampsia using validated genetic loci for C-reactive protein.

METHODS

Preeclampsia cases (n = 177) and normotensive controls (n = 116) were selected from live birth certificates to nulliparous Iowa women during the period August 2002-May 2005. Disease status was verified by the medical chart review. Genetic predisposition to CRP was estimated by a genetic risk score on the basis of established loci for CRP levels. Logistic regression analyses were used to evaluate the relationships between the genotype score and preeclampsia. Replication analyses were performed in an independent, US population of preeclampsia cases (n = 516) and controls (n = 1,097) of European ancestry.

RESULTS

The genetic risk score (GRS) related to higher levels of CRP demonstrated a significantly decreased risk of preeclampsia (OR 0.89, 95% CI 0.82-0.96). When the GRS was analyzed by quartile, an inverse linear trend was observed (p = 0.0006). The results were similar after adjustments for the body mass index (BMI), smoking, and leisure-time physical activity. In the independent replication population, the association with the CRP GRS was also marginally significant (OR 0.97, 95% CI 0.92, 1.02). Meta-analysis of the two studies was statistically significant (OR 0.95, 95% CI 0.90, 0.99).

CONCLUSION

Our data suggest an inverse, counterintuitive association between the genetic predisposition to elevated levels of CRP and a decreased risk of preeclampsia. This suggests that the blood CRP level is a marker of preeclampsia, but it does not appear to be a factor on the causal pathway.

Role of Serpine Gene Polymorphism in Recurrent Implantation Failure and Preeclampsia

This is a rare case of serpine gene polymorphism causing thrombophilia and recurrent implantation failure following intrauterine insemination. SERPINE1 gene encodes plasminogen activator inhibitor type 1 and inhibits fibrinolysis, or clot dissolution. The 4G variant results in increased expression of SERPINE1 and consequently higher inhibition of fibrinolysis, thus leading to thrombophilia. The patient had unexplained primary infertility for 9 years. Ovulation induction was done with gonadotropin releasing hormone (GnRH) agonist long protocol. Recombinant follicle stimulating hormone (FSH) with step down protocol was used. Ovulation trigger was given with recombinant human chorionic gonadotrophin (HCG). Ovum pick up was done after 40 h of trigger. A total of 13 eggs were collected. Patient was put on Cabergoline to prevent ovarian hyperstimulation syndrome (OHSS). Four frozen embryos were transferred on day 14 after Laser-assisted hatching. EmbryoGlue was used to prevent implantation failure. Luteal phase support was given. She was put on enoxaparin and pregnancy has now been confirmed. The patient was on strict monitoring as this gene is also associated with preeclampsia during pregnancy.

The Pre-Eclampsia Ontology: A Disease Ontology Representing the Domain Knowledge Specific to Pre-Eclampsia

Pre-eclampsia (PE) is a clinical syndrome characterized by new-onset hypertension and proteinuria at ≥20 weeks of gestation, and is a leading cause of maternal and perinatal morbidity and mortality. Previous studies have gathered abundant data about PE such as risk factors and pathological findings. However, most of these data are not semantically structured. Clinical data on PE patients are often generated with semantic heterogeneity such as using disparate terminology to describe the same phenomena. In clinical studies, interoperability of heterogenic clinical data is required in various situations. In such a situation, it is necessary to develop an interoperable and standardized semantic framework to research the pathology of PE more comprehensively and to achieve interoperability of heterogenic clinical data of PE patients. In this study, we developed an ontology representing clinical features, treatments, genetic factors, environmental factors, and other aspects of the current knowledge in the domain of PE. We call this pre-eclampsia ontology “PEO”. To achieve interoperability with other ontologies, the core structure of PEO was compliant with the hierarchy of the Basic Formal Ontology (BFO). The PEO incorporates a wide range of key concepts and terms of PE from clinical and biomedical research in structuring the knowledge base that is specific to PE; therefore, PEO is expected to enhance PE-specific information retrieval and knowledge discovery in both clinical and biomedical research fields.

Comparison of Normal and Pre-Eclamptic Placental Gene Expression: A Systematic Review with Meta-Analysis

Pre-eclampsia (PE) is a serious multi-factorial disorder of human pregnancy. It is associated with changes in the expression of placental genes. Recent transcription profiling of placental genes with microarray analyses have offered better opportunities to define the molecular pathology of this disorder. However, the extent to which placental gene expression changes in PE is not fully understood. We conducted a systematic review of published PE and normal pregnancy (NP) control placental RNA microarrays to describe the similarities and differences between NP and PE placental gene expression, and examined how these differences could contribute to the molecular pathology of the disease. A total of 167 microarray samples were available for meta-analysis. We found the expression pattern of one group of genes was the same in PE and NP. The review also identified a set of genes (PE unique genes) including a subset, that were significantly (p < 0.05) down-regulated in pre-eclamptic placentae only. Using class prediction analysis, we further identified the expression of 88 genes that were highly associated with PE (p < 0.05), 10 of which (LEP, HTRA4, SPAG4, LHB, TREM1, FSTL3, CGB, INHA, PROCR, and LTF) were significant at p < 0.001. Our review also suggested that about 30% of genes currently being investigated as possibly of importance in PE placenta were not consistently and significantly affected in the PE placentae. We recommend further work to confirm the roles of the PE unique and associated genes, currently not being investigated in the molecular pathology of the disease.

An RGS2 3'UTR polymorphism is associated with preeclampsia in overweight women

BACKGROUND

Preeclampsia is a common and heterogeneous vascular syndrome of pregnancy. Its genetic risk profile is yet unknown and may vary between individuals and populations. The rs4606 3' UTR polymorphism of the Regulator of G-protein signaling 2 gene (RGS2) in the mother has been implicated in preeclampsia as well as in the development of chronic hypertension after preeclampsia. The RGS2 protein acts as an inhibitor of physiological vasoconstrictive pathways, and a low RGS2 level is associated with hypertension and obesity, two conditions that predispose to preeclampsia. We genotyped the rs4606 polymorphism in 1339 preeclamptic patients and in 697 controls from the Finnish Genetics of Preeclampsia Consortium (FINNPEC) cohort to study the association of the variant with preeclampsia.

RESULTS

No association between rs4606 and preeclampsia was detected in the analysis including all women. However, the polymorphism was associated with preeclampsia in a subgroup of overweight women (body mass index ≥ 25 kg/m(2), and < 30 kg/m(2)) (dominant model; odds ratio, 1.64; 95 % confidence interval, 1.10-2.42).

CONCLUSIONS

Our results suggest that RGS2 might be involved in the pathogenesis of preeclampsia particularly in overweight women and contribute to their increased risk for hypertension and other types of cardiovascular disease later in life.

Exome sequencing in pooled DNA samples to identify maternal pre-eclampsia risk variants

Pre-eclampsia is a common pregnancy disorder that is a major cause for maternal and perinatal mortality and morbidity. Variants predisposing to pre-eclampsia might be under negative evolutionary selection that is likely to keep their population frequencies low. We exome sequenced samples from a hundred Finnish pre-eclamptic women in pools of ten to screen for low-frequency, large-effect risk variants for pre-eclampsia. After filtering and additional genotyping steps, we selected 28 low-frequency missense, nonsense and splice site variants that were enriched in the pre-eclampsia pools compared to reference data, and genotyped the variants in 1353 pre-eclamptic and 699 non-pre-eclamptic women to test the association of them with pre-eclampsia and quantitative traits relevant for the disease. Genotypes from the SISu project (n = 6118 exome sequenced Finnish samples) were included in the binary trait association analysis as a population reference to increase statistical power. In these analyses, none of the variants tested reached genome-wide significance. In conclusion, the genetic risk for pre-eclampsia is likely complex even in a population isolate like Finland, and larger sample sizes will be necessary to detect risk variants.

Association Between Gene Polymorphisms on Chromosome 1 and Susceptibility to Pre-Eclampsia: An Updated Meta-Analysis

Background

This meta-analysis enabled us to obtain a precise estimation of the association between gene polymorphisms on chromosome 1 (MTHFR, AGT, F5, IL-10, LEPR) and the susceptibility to pre-eclampsia (PE) in order to reach a uniform conclusion.

Material/Methods

Web of Science, PubMed, EMBASE, Cochran Library (CENTRAL), and Chinese databases (Chinese National Knowledge Infrastructure-CNKI and Wan Fang) were electronically searched to select relevant studies for this meta-analysis. We selected 95 case-control studies investigating 5 genes (MTHFR, AGT, F5, IL-10, and LEPR) with 8 SNPs. Odds ratios (OR) with their 95% confidence intervals (CI) were used for estimating the association.

Results

A total of 16 646 PE patients and 28 901 normal-pregnancy patients were included in this meta-analysis. The overall results suggested that rs1801133 of MTHFR (OR=1.17, 95% CI: 1.05–1.13) and rs6025 of F5 (OR=1.53, 95%CI: 1.07–2.20) are significantly associated with PE, whereas rs1801131 of MTHFR, rs699 and rs4762 of AGT, rs1800896 and rs1800871 of IL-10, and rs1137101 of LEPR have no significant association with PE. Subgroup analysis by ethnicity revealed that, except for MTHFR rs1801133 and F5 rs6025 in Caucasians, which were significantly associated with an increased risk of PE, none of these SNPs were significantly associated with PE. As suggested by a symmetric funnel plot in conjunction with the Egger’s test, there was no significant publication bias in MTHFR rs1801133 (P=0.318) and rs1801131 (P=0.204), F5 rs6025 (P=0.511), LEPR rs1137101 (P=0.511), AGT rs4762 (P=0.215) and rs699 (P=0.482), IL-10 rs1800871 (P=0.955), and rs1800896 (P=0.144).

Conclusions

This meta-analysis provides evidence that MTHFR rs1801133 and F5 rs6025 are associated with an increased risk of PE, especially in Caucasians. However, we do not have sufficient evidence to conclude there is a significant association between other gene polymorphisms and PE.