Placenta-derived, cellular messenger RNA expression in the maternal blood of preeclamptic women

10. Role of high dimensional technology in preeclampsia (omics in preeclampsia)

Preeclampsia is a pregnancy-specific disease that has no known precise cause. Integrative biology approach based on multi-omics has been applied to identify upstream pathways and better understand the pathophysiology of preeclampsia. At DNA level, genomics and epigenomics studies have revealed numerous genetic variants associated with preeclampsia, including those involved in regulating blood pressure and immune response. Transcriptomics analyses have revealed altered expression of genes in preeclampsia, particularly those related to inflammation and angiogenesis. At protein level, proteomics studies have identified potential biomarkers for preeclampsia diagnosis and prediction in addition to revealing the main pathophysiological pathways involved in this disease. At metabolite level, metabolomics has highlighted altered lipid and amino acid metabolisms in preeclampsia. Finally, microbiomics studies have identified dysbiosis in the gut and vaginal microbiota in pregnant women with preeclampsia. Overall, omics technologies have improved our understanding of the complex molecular mechanisms underlying preeclampsia. However, further research is warranted to fully integrate and translate these omics findings into clinical practice.

Unveiling the hidden players: The crucial role of transposable elements in the placenta and their potential contribution to pre-eclampsia

The human placenta is a vital connection between maternal and fetal tissues, allowing for the exchange of molecules and modulation of immune interactions during pregnancy. Interestingly, some of the placenta's unique functions can be attributed to transposable elements (TEs), which are DNA sequences that have mobilised into the genome. Co-option throughout mammalian evolution has led to the generation of TE-derived regulators and TE-derived genes, some of which are expressed in the placenta but silenced in somatic tissues. TE genes encompass both TE-derived genes with a repeat element in the coding region and TE-derived regulatory regions such as alternative promoters and enhancers. Placental-specific TE genes are known to contribute to the placenta's unique functions, and interestingly, they are also expressed in some cancers and share similar functions. There is evidence to support that aberrant activity of TE genes may contribute to placental pathologies, cancer and autoimmunity. In this review, we highlight the crucial roles of TE genes in placental function, and how their dysregulation may lead to pre-eclampsia, a common and dangerous placental condition. We provide a summary of the functional TE genes in the placenta to offer insight into their significance in normal and abnormal human development. Ultimately, this review highlights an opportunity for future research to investigate the potential dysregulation of TE genes in the development of placental pathologies such as pre-eclampsia. Further understanding of TE genes and their role in the placenta could lead to significant improvements in maternal and fetal health.

Differential Expression of NME4 in Trophoblast Stem-Like Cells and Peripheral Blood Mononuclear Cells of Normal Pregnancy and Preeclampsia

BACKGROUND

Preeclampsia (PE) is known to arise from insufficient trophoblast invasion as uterine spiral arteries lack remodeling. A significant reduction in placental perfusion induces an ischemic placental microenvironment due to reduced oxygen delivery to the placenta and fetus, leading to oxidative stress. Mitochondria are involved in the regulation of cellular metabolism and the production of reactive oxygen species (ROS). NME/NM23 nuceloside diphosphate kinase 4 (NME4) gene is known to have the ability to supply nucleotide triphosphate and deoxynucleotide triphosphate for replication and transcription of mitochondria. Our study aimed to investigate changes in NME4 expression in PE using trophoblast stem-like cells (TSLCs) from induced pluripotent stem cells (iPSCs) as a model of early pregnancy and peripheral blood mononuclear cells (PBMNCs) as a model of late preterm pregnancy.

METHODS

Transcriptome analysis using TSLCs was performed to identify the candidate gene associated with the possible pathophysiology of PE. Then, the expression of NME4 associated with mitochondrial function, p53 associated with cell death, and thioredoxin (TRX) linked to ROS were investigated through qRT-PCR, western blotting and deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick end labelling (TUNEL) assay.

RESULTS

In patients with PE, NME4 was significantly downregulated in TSLCs but upregulated in PBMNCs. p53 was shown to be upregulated in TSLCs and PBMNCs of PE. In addition, western blot analysis confirmed that TRX expression had the tendency to increase in TSLCs of PE. Similarly, TUNEL analysis confirmed that the dead cells were higher in PE than in normal pregnancy.

CONCLUSION

Our study showed that the expression of the NME4 differed between models of early and late preterm pregnancy of PE, and suggests that this expression pattern may be a potential biomarker for early diagnosis of PE.

Inflammation in Preeclampsia: Genetic Biomarkers, Mechanisms, and Therapeutic Strategies

Objective

Preeclampsia is a common and serious complication of pregnancy, posing a threat to maternal and fetal safety due to the lack of effective biomarkers and treatment strategies. This study aimed to identify potential biomarkers that can be used to predict preeclampsia and identify the molecular mechanisms of preeclampsia pathogenesis and drug prediction at the transcriptome level.

Methods

We analyzed differential expression genes (DEGs) in preeclampsia and non-preeclampsia groups in the GSE75010 dataset, cross-linking with extracted inflammatory response-related genes to obtain differentially expressed inflammation-related genes (DINRGs). Enrichment analysis and protein-protein interaction (PPI) networks were constructed to understand the functions and enrichment pathways. Machine learning models were used to identify key genes associated with preeclampsia and build a nomogram in the training set, which was validated in the validation set. The R package RcisTarget was used to predict transcription factors, and Cytoscape was used to construct miRNA-mRNA pathways, which could identify the molecular mechanisms. Then, we conducted molecular docking of the obtained key genes INHBA (inhibin subunit beta A), OPRK1 (opioid receptor kappa 1), and TPBG (trophoblast glycoprotein), as well as predicted transcription factors with drug molecules. Additionally, the CIBERSORT method explored the differences in immune cell infiltration between preeclampsia and non-preeclampsia samples based on the GSE75010 dataset.

Results

A total of 69 DINRGs associated with preeclampsia patients were screened. INHBA, OPRK1, and TPBG were the key genes based on machine learning models. A nomogram for prediction was further constructed, and the receiver operating curves (ROCs) showed good performance. Based on the transcriptome level of key genes, we proposed that RELA-miR-548K/miR-1206-TPBG may be a potential RNA regulatory pathway regulating the progression of early preeclampsia. Molecular docking suggested the effectiveness of curcumin in the treatment of preeclampsia. Additionally, regulatory T cells (Tregs) and resting mast cells were significantly different between the two groups.

Conclusion

In summary, we identified three key inflammation-associated genes, namely INHBA, OPRK1, and TPBG, which can be used as potential genetic biomarkers for preeclampsia prediction and treatment, and established a nomogram as a predictive model. Additionally, we provided insights into the mechanisms of preeclampsia development at the transcriptome level and performed corresponding drug predictions.

Biosensors for Detection of Human Placental Pathologies: A Review of Emerging Technologies and Current Trends

Substantial growth in the biosensor research has enabled novel, sensitive and point-of-care diagnosis of human diseases in the last decade. This paper presents an overview of the research in the field of biosensors that can potentially predict and diagnosis of common placental pathologies. A survey of biomarkers in maternal circulation and their characterization methods is presented, including markers of oxidative stress, angiogenic factors, placental debris, and inflammatory biomarkers that are associated with various pathophysiological processes in the context of pregnancy complications. Novel biosensors enabled by microfluidics technology and nanomaterials is then reviewed. Representative designs of plasmonic and electrochemical biosensors for highly sensitive and multiplexed detection of biomarkers, as well as on-chip sample preparation and sensing for automatic biomarker detection are illustrated. New trends in organ-on-a-chip based placental disease models are highlighted to illustrate the capability of these in vitro disease models in better understanding the complex pathophysiological processes, including mass transfer across the placental barrier, oxidative stress, inflammation, and malaria infection. Biosensor technologies that can be potentially embedded in the placental models for real time, label-free monitoring of these processes and events are suggested. Merger of cell culture in microfluidics and biosensing can provide significant potential for new developments in advanced placental models, and tools for diagnosis, drug screening and efficacy testing.

Gestational diabetic transcriptomic profiling of microdissected human trophoblast

Gestational diabetes mellitus (GDM), the most common metabolic complication of pregnancy, is influenced by the placenta, and its prevalence directly increases with obesity. Therefore, to define the aetiology of GDM requires that the confounding influence of obesity and the heterogeneous nature of the placenta impairing accurate quantitative studies be accounted for. Using laser capture microdissection (LCM), we optimized RNA extraction from human placental trophoblast, the metabolic cellular interface between mother and foetus. This allowed specific transcriptomic profiling of trophoblast isolated from GDM, and obese and normal human placentae. Genome-wide gene expression analysis was performed on the RNA extracted from the trophoblast of GDM and obese and normal placentae. Forty-five differentially expressed genes (DEGs) specifically discriminated GDM from matched obese subjects. Two genes previously linked with GDM, pregnancy specific beta-1 glycoprotein 6 (PSG6) and placental system A sodium-dependent transporter system (SLC38A1), were significantly increased in GDM. A number of these DEGs (8 ubiquitin-conjugating enzymes (UBE) splice variants (UBE2D3 variants 1, 3, 4, 5, 6, 7, and 9) and UBE2V1 variant 4)) were involved in RNA processing and splicing, and a significant number of the DEGs, including the UBE variants, were associated with increased maternal fasting plasma glucose.It is concluded that DEGs discriminating GDM from obese subjects were pinpointed. Our data indicate a biological link between genes involved in RNA processing and splicing, ubiquitination, and fasting plasma glucose in GDM taking into account obesity as the confounder.

The Role of RNAs and microRNAs in Non-Invasive Prenatal Diagnosis

In this paper, all possible clinical applications of circulating mRNA and miRNA for non-invasive prenatal diagnosis appearing in the medical literature so far are described. Data from the literature have also been reported and commented on along with some possible future applications.

Quantifying circulating hypoxia-induced RNA transcripts in maternal blood to determine in utero fetal hypoxic status

BACKGROUND

Hypoxia in utero can lead to stillbirth and severe perinatal injury. While current prenatal tests can identify fetuses that are hypoxic, none can determine the severity of hypoxia/acidemia. We hypothesized a hypoxic/acidemic fetus would up-regulate and release hypoxia-induced mRNA from the fetoplacental unit into the maternal circulation, where they can be sampled and quantified. Furthermore, we hypothesized the abundance of hypoxia induced mRNA in the maternal circulation would correlate with severity of fetal hypoxia/acidemia in utero. We therefore examined whether abundance of hypoxia-induced mRNA in the maternal circulation correlates with the degree of fetal hypoxia in utero.

METHODS

We performed a prospective study of two cohorts: 1) longitudinal study of pregnant women undergoing an induction of labor (labor induces acute fetal hypoxia) and 2) pregnancies complicated by severe preterm growth restriction (chronic fetal hypoxia). For each cohort, we correlated hypoxia induced mRNA in the maternal blood with degree of fetal hypoxia during its final moments in utero, evidenced by umbilical artery pH or lactate levels obtained at birth. Gestational tissues and maternal bloods were sampled and mRNAs quantified by microarray and RT-PCR.

RESULTS

Hypoxia-induced mRNAs in maternal blood rose across labor, an event that induces acute fetal hypoxia. They exhibited a precipitous increase across the second stage of labor, a particularly hypoxic event. Importantly, a hypoxia gene score (sum of the relative expression of four hypoxia-induced genes) strongly correlated with fetal acidemia at birth. Hypoxia-induced mRNAs were also increased in the blood of women carrying severely growth restricted preterm fetuses, a condition of chronic fetal hypoxia. The hypoxia gene score correlated with the severity of ultrasound Doppler velocimetry abnormalities in fetal vessels. Importantly, the hypoxia gene score (derived from mRNA abundance in maternal blood) was significantly correlated with the degree of fetal acidemia at birth in this growth restriction cohort.

CONCLUSIONS

Abundance of mRNAs coding hypoxia-induced genes circulating in maternal blood strongly correlates with degree of fetal hypoxia/acidemia. Measuring hypoxia-induced mRNA in maternal blood may form the basis of a novel non-invasive test to clinically determine the degree of fetal hypoxia/acidemia while in utero.

Co-expression network analysis and genetic algorithms for gene prioritization in preeclampsia

BACKGROUND

In this study, we explored the gene prioritization in preeclampsia, combining co-expression network analysis and genetic algorithms optimization approaches. We analysed five public projects obtaining 1,146 significant genes after cross-platform and processing of 81 and 149 microarrays in preeclamptic and normal conditions, respectively.

METHODS

After co-expression network construction, modular and node analysis were performed using several approaches. Moreover, genetic algorithms were also applied in combination with the nearest neighbour and discriminant analysis classification methods.

RESULTS

Significant differences were found in the genes connectivity distribution, both in normal and preeclampsia conditions pointing to the need and importance of examining connectivity alongside expression for prioritization. We discuss the global as well as intra-modular connectivity for hubs detection and also the utility of genetic algorithms in combination with the network information. FLT1, LEP, INHA and ENG genes were identified according to the literature, however, we also found other genes as FLNB, INHBA, NDRG1 and LYN highly significant but underexplored during normal pregnancy or preeclampsia.

CONCLUSIONS

Weighted genes co-expression network analysis reveals a similar distribution along the modules detected both in normal and preeclampsia conditions. However, major differences were obtained by analysing the nodes connectivity. All models obtained by genetic algorithm procedures were consistent with a correct classification, higher than 90%, restricting to 30 variables in both classification methods applied.Combining the two methods we identified well known genes related to preeclampsia, but also lead us to propose new candidates poorly explored or completely unknown in the pathogenesis of preeclampsia, which may have to be validated experimentally.

Differences and similarities in the transcriptional profile of peripheral whole blood in early and late-onset preeclampsia: insights into the molecular basis of the phenotype of preeclampsiaa

OBJECTIVE

Preeclampsia (PE) can be sub-divided into early- and late-onset phenotypes. The pathogenesis of these two phenotypes has not been elucidated. To gain insight into the mechanisms of disease, the transcriptional profiles of whole blood from women with early- and late-onset PE were examined.

METHODS

A cross-sectional study was conducted to include women with: i) early-onset PE (diagnosed prior to 34 weeks, n=25); ii) late-onset PE (after 34 weeks, n=47); and iii) uncomplicated pregnancy (n=61). Microarray analysis of mRNA expression in peripheral whole blood was undertaken using Affymetrix microarrays. Differential gene expression was evaluated using a moderated t-test (false discovery rate <0.1 and fold change >1.5), adjusting for maternal white blood cell count and gestational age. Validation by real-time qRT-PCR was performed in a larger sample size [early PE (n=31), late PE (n=72) and controls (n=99)] in all differentially expressed genes. Gene ontology analysis and pathway analysis were performed.

RESULTS

i) 43 and 28 genes were differentially expressed in early- and late-onset PE compared to the control group, respectively; ii) qRT-PCR confirmed the microarray results for early and late-onset PE in 77% (33/43) and 71% (20/28) of genes, respectively; iii) 20 genes that are involved in coagulation (SERPINI2), immune regulation (VSIG4, CD24), developmental process (H19) and inflammation (S100A10) were differentially expressed in early-onset PE alone. In contrast, only seven genes that encoded proteins involved in innate immunity (LTF, ELANE) and cell-to-cell recognition in the nervous system (CNTNAP3) were differentially expressed in late-onset PE alone. Thirteen genes that encode proteins involved in host defense (DEFA4, BPI, CTSG, LCN2), tight junctions in blood-brain barrier (EMP1) and liver regeneration (ECT2) were differentially expressed in both early- and late-onset PE.

CONCLUSION

Early- and late-onset PE are characterized by a common signature in the transcriptional profile of whole blood. A small set of genes were differentially regulated in early- and late-onset PE. Future studies of the biological function, expression timetable and protein expression of these genes may provide insight into the pathophysiology of PE.

From prenatal genomic diagnosis to fetal personalized medicine: progress and challenges

Thus far, the focus of personalized medicine has been the prevention and treatment of conditions that affect adults. Although advances in genetic technology have been applied more frequently to prenatal diagnosis than to fetal treatment, genetic and genomic information is beginning to influence pregnancy management. Recent developments in sequencing the fetal genome combined with progress in understanding fetal physiology using gene expression arrays indicate that we could have the technical capabilities to apply an individualized medicine approach to the fetus. Here I review recent advances in prenatal genetic diagnostics, the challenges associated with these new technologies and how the information derived from them can be used to advance fetal care. Historically, the goal of prenatal diagnosis has been to provide an informed choice to prospective parents. We are now at a point where that goal can and should be expanded to incorporate genetic, genomic and transcriptomic data to develop new approaches to fetal treatment.

Maternal serum proteome changes between the first and third trimester of pregnancy in rural southern Nepal

Characterization of normal changes in the serum proteome during pregnancy may enhance understanding of maternal physiology and lead to the development of new gestational biomarkers. In 23 Nepalese pregnant women who delivered at term, two-dimensional difference in-gel electrophoresis (DIGE) was used to assess changes in relative protein abundance between paired serum samples collected in the first and third trimesters. One-hundred and forty-five of over 700 protein spots in DIGE gels (pI 4.2-6.8) exhibited nominally significant (p < 0.05) differences in abundance across trimesters. Additional filtering using a Bonferroni correction reduced the number of significant (p < 0.00019) spots to 61. Mass spectrometric analysis detected 38 proteins associated with gestational age, cytoskeletal remodeling, blood pressure regulation, lipid and nutrient transport, and inflammation. One new protein, pregnancy-specific β-glycoprotein 4 was detected. A follow-up isotope tagging for relative and absolute quantitation (iTRAQ) experiment of six mothers from the DIGE study revealed 111 proteins, of which 11 exhibited significant (p < 0.05) differences between trimesters. Four of these proteins: gelsolin, complement C1r subcomponent, α-1-acid glycoprotein, and α-1B-glycoprotein also changed in the DIGE analysis. Although not previously associated with normal pregnancy, gelsolin decreased in abundance by the third trimester (p < 0.01) in DIGE, iTRAQ and Western analyses. Changes in abundance of proteins in serum that are associated with syncytiotrophoblasts (gelsolin, pregnancy-specific β-1 glycoprotein 1 and β-2-glycoprotein I) probably reflect dynamics of a placental proteome shed into maternal circulation during pregnancy. Measurement of changes in the maternal serum proteome, when linked with birth outcomes, may yield biomarkers for tracking reproductive health in resource poor settings in future studies.

Measurement of mRNA transcripts of very high placental expression in maternal blood as biomarkers of preeclampsia

CONTEXT

mRNA of placental origin in maternal blood shows potential as a clinical biomarker of obstetric diseases such as preeclampsia (PE). We hypothesized that mRNA transcripts very highly expressed in the placenta relative to other tissues will be differentially expressed in PE and be useful as mRNA biomarkers in maternal blood.

OBJECTIVE

Our objective was to identify a panel of genes highly expressed in the placenta and compare their expression in placenta and maternal whole blood from PE vs. control pregnancies.

SETTING

Placental tissue and maternal whole blood specimens were obtained from normotensive controls (n = 15) and pregnancies complicated by severe preterm PE (n = 21).

INTERVENTION

mRNA expression was evaluated by quantitative real-time RT-PCR.

RESULTS

We identified 20 genes exhibiting highest to fourth highest expression in the placenta relative to all other tissues. All genes were detectable in placenta. Nine of the 20 genes were detectable in maternal whole blood. Four of the nine genes detectable in blood (i.e. PLAC3, PLAC4, CRH, and ERVWE1) were significantly increased in both maternal blood and placenta from PE pregnancies. The remaining five genes detectable in maternal blood were unchanged in both blood and placenta from PE pregnancies. Thus, there was complete correlation of gene expression between maternal blood and placenta.

CONCLUSIONS

Circulating mRNA coding genes of high placental expression show strong correlation with transcript levels in preeclamptic placenta. Such transcripts may be promising candidates to screen as mRNA biomarkers of PE in maternal whole blood.

Expression profile of microRNAs and mRNAs in human placentas from pregnancies complicated by preeclampsia and preterm labor

MicroRNAs (miRNAs) have emerged as key regulators of gene expression stability implicated in cell proliferation, apoptosis, and development, whereas their altered expression has been associated with various pathological disorders. The objective of this study was to assess the expression profile of miRNAs and their predicted target genes in placentas from patients with preeclampsia (PC) and preterm (PT) labor as compared to normal term (NT) pregnancies. Using microarray profiling of 820 miRNAs and 18,630 mRNA transcripts, the analysis indicated that 283 of these miRNAs and 9119 mRNAs were expressed in all placentas, of which the relative expression of 20 miRNAs (P < .05 and ≥ 1.5-fold) and 120 mRNAs (P < .05, and 2-fold cutoff) was differentially expressed in PT and PC as compared to NT. The expression of miR-15b, miR-181a, miR-200C, miR-210, miR-296-3p, miR-377, miR-483-5p, and miR-493 and a few of their predicted target genes: matrix metalloproteinases (MMP-1, MMP-9), a disintegrin and metalloproteinase domains (ADAM-17, ADAM-30), tissue inhibitor of metalloproteinase 3 (TIMP-3); suppressor of cytokine signaling 1 (SOCS1); Stanniocalcin (STC2); corticotropin-releasing hormone (CRH), CRH-binding protein (CRHBP); and endothelin-2 (EDN2) were validated in these cohorts using real-time polymerase chain reaction (PCR), some displaying an inverse correlation with the expression of their predicted target genes. Functional analysis indicated that the products of these genes regulate cellular activities considered critical in normal placental functions and those affected by PC and PT labor. In conclusion, the results provide further evidence that placentas affected by PC and PT labor display an altered expression of a number of miRNAs with potential regulatory functions on the expression of specific target genes whose altered expression and function have been associated with these pregnancy complications.

Maternal gene expression profiling during pregnancy and preeclampsia in human peripheral blood mononuclear cells

Preeclampsia is a major obstetrical complication affecting maternal and fetal health. While it is clear that there is a substantial placental contribution to preeclampsia pathogenesis, the maternal contribution is less well characterized. We therefore performed a genome-wide transcriptome analysis to explore disease-associated changes in maternal gene expression patterns in peripheral blood mononuclear cells (PBMCs).

METHODS

Preeclampsia was defined as gestational hypertension, proteinuria and hyperurecimia. Total RNA was isolated from PBMCs obtained from women with uncomplicated pregnancies (n = 5) and women with preeclamptic pregnancies (n = 5). Gene expression analysis was carried out using Agilent oligonucleotide microarrays. Biological pathway analysis was undertaken using Ingenuity Pathway Analysis software. Quantitative real-time PCR (QRTPCR) was performed to validate the gene expression changes of selected genes in normotensive and preeclamptic patients (n = 12 each).

RESULTS

We identified a total of 368 genes that were differentially expressed in women with preeclampsia compared to normal controls with false discovery rate (FDR) controlled at 10%. In follow up experiments we further analyzed the expression levels of a number of genes that were identified as altered by the microarray data including survivin (BIRC5), caveolin (CAV1), GATA binding protein-1 (GATA1), signal tranducer and activator of transcription 1 (STAT1), E2F transcription factor-1 (E2F1), fibronectin-1 (FN1), interleukin-4 (IL-4), matrix metalloprotease-9 (MMP-9) and WAP four disulfide domain protein (WFDC-1) by QRTPCR. Additionally we performed immuno blot analysis and zymography to verify some of these candidate genes at the protein level. Computational analysis of gene function identified an anti-proliferative and altered immune function cellular phenotype in severe preeclamptic samples.

CONCLUSIONS

We have characterized the genome-wide mRNA expression changes associated with preeclampsia-specific genes in circulating maternal blood cells at the time of delivery. In addition to providing information relating to the biological basis of the preeclampsia phenotype, our data provide a number of potential biomarkers for use in the further characterization of this disease.

Genome profiles in maternal blood during early onset preeclampsia and towards term

AIMS

inflammatory processes are present during preeclampsia and in normal pregnancy. Maternal inflammatory reactions may change towards term. Our objective was to evaluate genome signaling in blood during preeclampsia and towards term using microarrays.

METHODS

RNA microarrays (Illumina) were conducted on blood from preeclamptic pregnancies delivered preterm, normal pregnancies at term and normal pregnancies at gestational week 31. Two statistical methods (Q-value cut-off 1%) identified data structures in the three groups and retrieved activated genes along a time axis and a diseased-healthy axis. Signaling genes were localized within known pathways and gene sets, and genes associated with inflammation were identified.

RESULTS

early onset preeclampsia and term pregnancies both showed distinct expression patterns when compared to normal pregnancy at gestational week 31. In preeclampsia, 19 genes were differentially expressed, including a down-regulation of CC-chemokine receptor 3 (CCR3). Among the 183 differentially expressed genes towards term, tumor necrosis factor superfamily member 15 (TNFSF15) was up-regulated and interferon-γ receptor 2 (IFNGR2) and CXC-chemokine receptor type 4 (CXCR4) were down-regulated. Seven of the genes were similarly changed during preeclampsia and towards term.

CONCLUSIONS

a possible type 1 immune response was identified both during preeclampsia and towards term. In pre-eclampsia a premature activation of leucocytes might be present.

PP13 mRNA expression in the cellular component of maternal blood as a marker for preeclampsia

OBJECTIVE

To assess the PP13 expression in the cellular component of blood in both preeclamptic patients and asymptomatic pregnant women during the early second trimester.

METHODS

In the case-control study, peripheral blood samples were obtained from pregnant women with preeclampsia (n = 24) and controls (n = 22). PP13 RNA expression was quantified in the cellular component of the blood by reverse transcription PCR assay. Next, as a cohort study of asymptomatic pregnant women at early gestation, cellular RNA from 41 cases who developed preeclampsia at later gestation and 123 cases of control were analysed, and the possibility of prediction of preeclampsia was assessed.

RESULTS

In symptomatic patients, PP13 level in preeclampsia was significantly lower than that in controls (p < 0.001). In the asymptomatic pregnant women, the PP13 level in preeclampsia was significantly lower than that in the controls (p = 0.008). A receiver-operating characteristics (ROC) curve yielded a detection rate of 24 and 31% at a false positive rate of 5 and 10% respectively.

CONCLUSION

An alteration in the cellular PP13 RNA expression would affect the placental pathophysiological change. The cellular PP13 expression level could therefore potentially be one of the key markers to predict the clinical onset of preeclampsia.

Gene expression profiling of maternal blood in early onset severe preeclampsia: identification of novel biomarkers

AIMS

To investigate candidate genes in peripheral blood mononuclear cell (PBMC) that are associated with early onset severe preeclampsia (ES-PE) and to describe candidate genes function using microarrays and real-time polymerase chain reaction (PCR).

METHODS

PBMC RNA was extracted from six patients with ES-PE and five uncomplicated pregnancies. The HG_U133 plus 2.0 Affymetrix GeneChips that represented 47,000 genes were used to measure gene expression in each sample. Significance analysis of microarray identified potential signature genes characterizing ES-PE vs. uncomplicated pregnancies. Eight genes were selected for confirmation by real-time PCR of 32 patients with ES-PE and 24 uncomplicated pregnancies, matched for maternal age, parity, race and gestational weeks.

RESULTS

Using a whole-genome approach to study the molecular determinants of ES-PE, 72 genes were found to be differentially expressed between cases and controls, including 38 up-regulated genes and 34 down-regulated genes in the group of ES-PE. Killer cell immunoglobulin-like receptor, three domains, long cytoplasmic tail, 2 (KIR3DL2), aldo-keto reductase family 1, member C3 (AKR1C3), churchill domain containing 1 (CHURC1), and solute carrier family 25, member 13 (SLC25A13) were validated to be down-regulated in the patients with ES-PE by real-time PCR.

CONCLUSIONS

Expression of genes with diverse function is associated with ES-PE risk, providing opportunities for the development of non-invasive diagnosis.

Cellular mRNA expressions of anti-oxidant factors in the blood of preeclamptic women

OBJECTIVE

To assess the alterations of mRNA expressions associated with oxidative stress in the cellular component of blood from pregnant women with pre-eclampsia.

METHODS

Peripheral blood samples were obtained from pregnant women with and without pre-eclampsia. Cellular RNA was subjected to a reverse transcription polymerase chain reaction (PCR) assay in order to examine the mRNA distribution among women with pre-eclampsia (n = 24) and control subjects (n = 24) during 35-41 weeks of gestation. The data were analyzed by non-parametric statistics.

RESULTS

Significant differences between the pre-eclampsia subjects and the controls were observed in the gene expressions associated with oxidative stress. Lower values in the pre-eclampsia group were found for heme oxygenase (HO)-1, HO-2, catalase and superoxide dismutase (SOD). The HO-1, HO-2 and the catalase levels significantly correlated with proteinuria, and the HO-2 level with systolic blood pressure.

CONCLUSION

Significantly lower concentrations of HO-1, HO-2, SOD and catalase are found in the cellular component of blood from pre-eclamptic patients. The values correlate with the severity of pre-eclampsia. These findings indicate that enhanced oxidative stress and a decrease in the number of anti-oxidant enzymes may be associated with pre-eclampsia.