The role and challenges of biomarkers in spontaneous preterm birth and preeclampsia

Hypertensive Disorders in Pregnancy: Global Burden From 1990 to 2019, Current Research Hotspots and Emerging Trends

Hypertensive disorders in pregnancy (HDP) constitute a worldwide health problem for pregnant women and their infants. This study provided HDP burden over 1990 to 2019 by region and age distribution, and predicted changes in related values for the next 25 years. We then conducted an econometric analysis of the author distribution, collaborative networks, keyword burst clustering, and spatio-temporal analysis of HDP-related publications from 2012 to 2022 to access current scientific developments and hotspots. The number of pregnant women with HDP has been increasing over the past 30 years, with regional and age-stratified differences in the burden of disease. Additionally, projections suggest an increase of deaths due to maternal HDP among adolescents younger than 20 years. Current research is mostly centered on pre-eclampsia, with hot keywords including trophoblast, immune tolerance, frozen-thawed embryo transfer, aspirin, gestational diabetes association, and biomarkers. Researches on the pathological mechanism, classification, and subtypes of HDP need to be further advanced.

Bioengineering and the cervix: The past, current, and future for addressing preterm birth

The uterine cervix plays two important but opposing roles during pregnancy - as a mechanical barrier that maintains the fetus for nine months and as a compliant structure that dilates to allow for the delivery of a baby. In some pregnancies, however, the cervix softens and dilates prematurely, leading to preterm birth. Bioengineers have addressed and continue to address the lack of reduction in preterm birth rates by developing novel technologies to diagnose, prevent, and understand premature cervical remodeling. This article highlights these existing and emerging technologies and concludes with open areas of research related to the cervix and preterm birth that bioengineers are currently well-positioned to address.

Diagnostic signature composed of seven genes in HIF-1 signaling pathway for preeclampsia

PURPOSE

In this study, we explored the relationship of genes in HIF-1 signaling pathway with preeclampsia and establish a logistic regression model for diagnose preeclampsia using bioinformatics analysis.

METHOD

Two microarray datasets GSE75010 and GSE35574 were downloaded from the Gene Expression Omnibus database, which was using for differential expression analysis. DEGs were performed the Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis and Gene set enrichment analysis (GSEA). Then we performed unsupervised consensus clustering analysis using genes in HIF-1 signaling pathway, and clinical features and immune cell infiltration were compared between these clusters, as well as the least absolute shrinkage and selection operator (LASSO) method to screened out key genes to constructed logistic regression model, and receiver operating characteristic (ROC) curve was plotted to evaluate the accuracy of the model.

RESULTS

57 DEGs were identified, of which GO, KEGG and analysis GSEA showed DEGs were mostly involved in HIF-1 signaling pathway. Two subtypes were identified of preeclampsia and 7 genes in HIF1-signaling pathway were screened out to establish the logistic regression model for discrimination preeclampsia from controls, of which the AUC are 0.923 and 0.845 in training and validation datasets respectively.

CONCLUSION

Seven genes (including MKNK1, ARNT, FLT1, SERPINE1, ENO3, LDHA, BCL2) were screen out to build potential diagnostic model of preeclampsia.

ACSF2-mediated ferroptosis is involved in ulcerative colitis

AIMS

To investigate the role of ferroptosis-related genes in the induction into ulcerative colitis (UC) and provide new strategies for the prevention and treatment of UC.

MATERIALS AND METHODS

We screened the UC dataset from the GEO database and obtained ferroptosis-related genes from FerrDB and GeneCards. The R package "CancerSubtypes" was performed to identify the UC subtypes, followed by Short Time-series Expression Miner (STEM) analysis. The key genes were further screened by machine learning algorithms (LASSO and SVM-RFE). WB and IHC verified the changes in the expression content of ACSF2 in vivo and in vitro models. The changes in intracellular ROS and Fe^{2 +} levels were detected.

KEY FINDINGS

Through bioinformatics analysis, we selected the ferroptosis-related gene ACSF2 (acyl CoA synthetase family member 2), which is significantly associated with immune-related pathways "Toll-like receptor signaling pathway", "NF-kappa B signaling pathway" and "NOD-like receptor signaling pathway". The expression of ACSF2 was significantly down-regulated in UC animals, Salmonella typhimurium colitis models and cell models, while the ferroptosis inhibitor Fer-1 reversed the expression of ACSF2 in LPS-induced cell models, indicating that the ferroptosis-related gene ACSF2 plays an important role in mediating ferroptosis and inflammation, and is expected to become a new target for further research.

SIGNIFICANCE

Ferroptosis is closely associated with the development of UC, and the ferroptosis-related gene ACSF2 can be used as a potential biomarker for the diagnosis and treatment of UC.

The effect of 150 and 80 mg doses of aspirin on preventing preterm birth in high-risk pregnant women

OBJECTIVES

Preterm birth (PTB) is the common cause of neonatal mortality nationwide. The present study aimed to evaluate the efficacy of different doses of aspirin in preventing PTB in high-risk pregnant women. As secondary outcomes, other perinatal complications were compared.

METHODS

This double-blind randomized clinical trial was conducted on high-risk pregnant women with impaired placental perfusion diagnosed in the first trimester of pregnancy referring to the perinatal centers affiliated to Shiraz university of Medical Sciences between February 2020 and March 2021. The subjects were randomly divided in two groups administered with 150 or 80 mg aspirin every night from 11 to 13+6 weeks until 36 weeks or delivery. This study is registered in the Iranian Registry of Clinical Trials (IRCT20140317017035N6; http://www.irct.ir/). Univariate and multiple logistic regressions were applied using SPSS 22.

RESULTS

A total of 101 subjects received 80 mg aspirin and 89 ones received 150 mg aspirin. The results of multiple analysis revealed a significantly lower odds of PTB (OR 0.4 (0.19, 0.99)) in the 150 mg group compared to the 80 mg group. As secondary outcomes, preeclampsia (PEC) and PEC with severe features (PECsf) were lower (OR 0.2 (0.06, 0.82) and 0.1 (0.01, 0.92), respectively); however, fetal age and neonatal weight were higher in the 150 mg group (OR 1.2 (1.04, 1.33) and 1.001 (1-1.001), respectively).

CONCLUSIONS

The study findings indicated that, compared with 80 mg of aspirin, taking 150 mg of aspirin reduced PTB and perinatal complications in high risk pregnant women.

Decreased Adiponectin Levels in Early Pregnancy Are Associated with High Risk of Prematurity for African American Women

The relationship of low maternal serum adiponectin levels with preterm delivery among a multi-ethnic group has not been extensively investigated. We examined ethnic differences in cytokine/adipokine profiles and whether they contribute to several adverse pregnancy outcomes, particularly preterm delivery. Data and samples were from a large prospective observational cohort (n = 1776) of young, generally healthy pregnant women (African American 36.4%, Hispanic 48.0%, Caucasian 15.6%). Serum cytokine/adipokine concentrations were measured at entry (mean gestational age of 16.83 weeks) using the Liminex xMap Technology. Multivariable analyses were performed. A significant difference in adiponectin level was observed among ethnic groups. African Americans had a decreased adiponectin and increased resistin levels compared to Hispanics and Caucasians (p < 0.05 to p < 0.0001 for each). Decreased adiponectin (lowest quartile) was positively associated with preterm delivery independent of usual risk factors (adjusted odds ratio (AOR) 1.46, 95% confidence interval (CI) 1.05, 2.04 for all preterm and AOR 1.84, 95% CI 1.07, 3.17 for early preterm births). The results were unchanged when women with preeclampsia were excluded. Similar results were observed in African Americans. Decreased adiponectin levels were not related to preterm birth in either Hispanics or Caucasians. Lower adiponectin levels were also significantly associated with an increased risk of developing gestational diabetes (AOR 1.72, 95% CI 1.05, 2.84) and preeclampsia (AOR 1.45, 95% CI 1.00, 2.14) in the whole cohort and in Caucasians. We did not find any consistent relationships between the other markers with outcome variables. Dysregulation in maternal adiponectin at early gestation is associated with an increased risk of preterm delivery. An ethnic difference in adiponectin levels may contribute to a higher preterm delivery rate in African American women.

Evaluating the diagnosis and treatment of Chlamydia trachomatis and Neisseria gonorrhoeae in pregnant women to prevent adverse neonatal consequences in Gaborone, Botswana: protocol for the Maduo study

BACKGROUND

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are extremely common sexually transmitted infections (STIs) that are associated with adverse birth and neonatal outcomes, and the risk of vertical transmission of CT and NG during delivery is high. The majority of CT and NG infections are asymptomatic and missed by the standard of care in most countries (treatment based on symptoms). Thus, it is likely that missed maternal CT and NG infections contribute to preventable adverse health outcomes among women and children globally. This study aims to assess the effectiveness of CT and NG testing for asymptomatic pregnant women to prevent adverse neonatal outcomes, understand the inflammatory response linking CT and NG infections to adverse neonatal outcomes, and conduct an economic analysis of the CT and NG testing intervention.

METHODS

The Maduo ("results" in Setswana) is a prospective, cluster-controlled trial in Gaborone, Botswana to compare a near point-of-care CT and NG testing and treatment intervention implemented in "study clinics" with standard antenatal care (World Health Organization-endorsed "syndromic management" strategy based on signs and symptoms without laboratory confirmation) implemented in "standard of care clinics" among asymptomatic pregnant women. The primary outcome is vertical transmission of CT/NG infection. Secondary outcomes include preterm birth (delivery < 37 completed weeks of gestation) and/or low birth weight (< 2500 g). The trial will also evaluate immunological and inflammatory markers of adverse neonatal outcomes, as well as the costs and cost-effectiveness of the intervention compared with standard care.

DISCUSSION

The Maduo study will improve our understanding of the effectiveness and cost-effectiveness of CT and NG testing among asymptomatic pregnant women. It will also increase knowledge about the CT/NG-related immune responses that might drive adverse neonatal outcomes. Further, results from this study could encourage expansion of STI testing during antenatal care in low resource settings and improve maternal and neonatal health globally.

TRIAL REGISTRATION

This trial is registered with ClinicalTrials.gov (Identifier NCT04955717, First posted: July 9, 2021)).

Prediction and Prevention of Preterm Birth: A Prospective, Randomized Intervention Trial

OBJECTIVE

 The study aimed to determine if a program of mid-trimester serum proteomics screening of women at low risk for spontaneous preterm birth (sPTB) and the use of a PTB risk-reduction protocol in those whose results indicated an increased risk of sPTB would reduce the likelihood of sPTB and its sequelae.

STUDY DESIGN

 Prospective comparison of birth outcomes in singleton pregnancies with mid-trimester cervical length ≥2.5 cm and at otherwise low risk for sPTB randomized to undergo or not undergo mid-trimester serum proteomics screening for increased risk of sPTB (NCT03530332). Screen-positive women were offered a group of interventions aimed at reducing the risk of spontaneous PTB. The primary outcome was the rate of sPTB <37 weeks, and secondary outcomes were gestational age at delivery, total length of neonatal stay, and NICU length of stay (LOS). Unscreened and screen-negative women received standard care. The adaptive study design targeted a sample size of 3,000 to 10,000 women to detect a reduction in sPTB from 6.4 to 4.7%. Due to limited resources, the trial was stopped early prior to data unblinding.

RESULTS

 A total of 1,191 women were randomized. Screened and unscreened women were demographically similar. sPTB <37 weeks occurred in 2.7% of screened women and 3.5% of controls (p = 0.41). In the screened compared with the unscreened group, there were no between-group differences in the gestational age at delivery, total length of neonatal stay, and NICU LOS. However, the NICU LOS among infants admitted for sPTB was significantly shorter (median = 6.8 days, interquartile range [IQR]: 1.8-8.0 vs. 45.5 days, IQR: 34.6-79.0; p = 0.005).

CONCLUSION

 Mid-trimester serum proteomics screening of women at low risk for sPTB and the use of a sPTB risk-reduction protocol in screen-positive patients did not significantly reduce the rate of sPTB compared with women not screened, though the trial was underpowered thus limiting the interpretation of negative findings. Infants in the screened group had a significantly shorter NICU LOS, a difference likely due to a reduced number of infants in the screened group that delivered <35 weeks.

KEY POINTS

· Mid-trimester serum proteomics screening of women at low risk for sPTB and the use of a sPTB risk-reduction protocol in screen-positive patients did not significantly reduce the rate of sPTB, though the trial was underpowered.. · NICU LOS following sPTB was significantly shortened among women who underwent screening and risk-reduction management.. · The use of serum biomarkers may contribute to a practical strategy to reduce sPTB sequelae..

Prospective association of maternal immune pro-inflammatory responsivity and regulation in pregnancy with length of gestation

PROBLEM

The immune system represents a leading pathway of interest in the pathophysiology of preterm birth. The majority of human clinical studies interrogating this pathway have utilized circulating immune biomarkers; however, these concentrations typically reflect only basal production but not key functional properties of the immune system, particularly variation in the pro-inflammatory response to antigen challenge and the regulation of this response. Thus, in this study, we utilized an ex vivo stimulation protocol that quantifies these processes, and we examined their prospective association with the gestation length and risk of preterm birth.

METHOD OF STUDY

Immune responsiveness and regulation were assessed in 128 pregnant women in mid-gestation using an ex vivo stimulation protocol. Maternal pro-inflammatory responsivity of leukocytes was quantified by assessing the release of the pro-inflammatory cytokines IL-6, TNF-α, and IL-1β in response to antigen stimulation, and regulation of the pro-inflammatory response was quantified by assessing the suppression of stimulated cytokine response upon co-incubation with increasing dexamethasone concentrations (ie, glucocorticoid receptor resistance; GRR).

RESULTS

Higher maternal GRR, indicating impaired regulation of the pro-inflammatory response, was significantly and independently associated with shorter gestational length (β = -0.42, p = .0091) and a 3.0-fold increase in risk for preterm birth (OR = 3.01, 95% CI = 1.17-7.70, p = .0218). Basal circulating IL-6 and TNF-α were not associated with either outcome.

CONCLUSION

The association of maternal GRR with length of gestation and preterm birth risk suggests that the processes represented by this measure-maternal pro-inflammatory propensity and immune regulation-may provide further mechanistic insight into the pathophysiology of preterm birth.

Urothelial cancer associated 1 (UCA1) regulates trophoblast viability, proliferation, and migration via modulating the UCA1/miR-455/RUNX2 signaling pathway

Spontaneous abortion (SA) is the spontaneous loss of a pregnancy before 20 gestational weeks. The causes of SA are still largely unknown. Long noncoding RNA (lncRNA) urothelial cancer associated 1 (UCA1) plays an important role in cellular progress. However, there is no report focusing on the role of UCA1 in SA. Here, we revealed that, compared with that in clinical samples from elective induced abortion, UCA1 expression was decreased in samples from SA patients as shown by qPCR method. The results demonstrated that UCA1 might be involved in the progress of SA. Then, we found that knockdown of UCA1 reduced cell viability and inhibited cell proliferation and migration of HTR-8/SVneo trophoblast cells as shown by CCK8, EdU, and Transwell methods. Furthermore, we demonstrated that UCA1 could act as a molecular sponge for miR-455 in HTR-8/SVneo cells as shown by luciferase reporter system method. In addition, miR-455 inhibited cell viability, cell proliferation and migration via regulating RUNX2 in HTR-8/SVneo cells. Ultimately, we illustrated that UCA1 plays its role via absorbing miR-455, thus promoting RUNX2 expression in HTR-8/SVneo cells. Collectively, this study first revealed the role and mechanism of UCA1 in the growth and migration of HTR-8/SVneo cells, indicating its potential as a diagnostic biomarker and therapeutic target for SA.

Preterm parturition and pre-eclampsia: The confluence of two great gestational syndromes

BACKGROUND

Preterm birth (PTB) and pre-eclampsia independently, and frequently concurrently, adversely affect the pregnancy outcomes of millions of mothers and infants worldwide each year.

OBJECTIVES

To fill the gap between PTB and pre-eclampsia, which continue to constitute the two most important current global challenges to maternal and perinatal health.

METHODS

Pubmed, Embase, and Cochrane databases were searched from inception until December 2019 using the terms spontaneous PTB (SPTB), indicated preterm delivery (IPTD), early-onset pre-eclampsia, and pre-eclampsia.

RESULTS

History of PTB and pre-eclampsia were the strongest risk factors contributing to the occurrence of SPTB or IPTB. The risk of PTB and pre-eclampsia among non-Hispanic African American women was higher than the rate among all other racial/ethnic groups in the United States. Low-dose aspirin (LDA) has been reported to reduce the risk of pre-eclampsia by at least 10% and PTB by at least 14%. Lastly, women and their fetuses who develop early-onset pre-eclampsia are at higher risk for developing hypertension and cardiovascular disease later in life.

CONCLUSIONS

While better clarity is needed, efforts to coordinate prevention of both PTB and pre-eclampsia, even though imperfect, are critically important as part of any program to make motherhood as safe as possible.

Profiles of circular RNAs in human placenta and their potential roles related to preeclampsia

To identify the profiles of circular RNAs (circRNAs) in human placental tissues and to explore the potential roles of dysregulated circRNAs in the pathological genesis of preeclampsia, expression profiles of circRNAs in human placentas were performed in this study. Utilizing high-throughput technology, based on fold changes and P values, 300 circRNAs that are differentially expressed between preeclampsia and normal placental tissues were identified. Among them, hg38_circ_0014736 and hsa_circ_0015382 were validated as significantly upregulated by real-time quantitative PCR with divergent primers. At the same time, hsa_circ_0007121 was significantly downregulated. GO analysis revealed that the three altered circRNAs had a relationship with transcription regulation, proliferation, protein binding, and response to hypoxia. KEGG analysis yielded that apoptosis, Wnt signaling, and HIF-1 pathways were significantly enriched. Interestingly, hsa_circ_0007121 was found to be expressed differently in plasma between preeclampsia and normal pregnancy and this difference could be detected before 20 gestational weeks. Besides, addition receiver operating characteristic (ROC) curve analysis showed that the area under the ROC curve of hsa_circ_0007121 reached 0.72 ([0.59-0.85], P = 0.004) with a sensitivity of 0.77 and specificity of 0.70. Collectively, this study demonstrates the existence of dysregulated circRNAs in the placenta of preeclampsia patients and annotates their potential roles in the pathogenesis of the disease. Encouragingly, hsa_circ_0007121 was found to be a potential noninvasive biomarker for the prediction of preeclampsia.

Differential Dynamics of the Maternal Immune System in Healthy Pregnancy and Preeclampsia

Preeclampsia is one of the most severe pregnancy complications and a leading cause of maternal death. However, early diagnosis of preeclampsia remains a clinical challenge. Alterations in the normal immune adaptations necessary for the maintenance of a healthy pregnancy are central features of preeclampsia. However, prior analyses primarily focused on the static assessment of select immune cell subsets have provided limited information for the prediction of preeclampsia. Here, we used a high-dimensional mass cytometry immunoassay to characterize the dynamic changes of over 370 immune cell features (including cell distribution and functional responses) in maternal blood during healthy and preeclamptic pregnancies. We found a set of eight cell-specific immune features that accurately identified patients well before the clinical diagnosis of preeclampsia (median area under the curve (AUC) 0.91, interquartile range [0.82-0.92]). Several features recapitulated previously known immune dysfunctions in preeclampsia, such as elevated pro-inflammatory innate immune responses early in pregnancy and impaired regulatory T (Treg) cell signaling. The analysis revealed additional novel immune responses that were strongly associated with, and preceded the onset of preeclampsia, notably abnormal STAT5ab signaling dynamics in CD4⁺T cell subsets (AUC 0.92, p = 8.0E-5). These results provide a global readout of the dynamics of the maternal immune system early in pregnancy and lay the groundwork for identifying clinically-relevant immune dysfunctions for the prediction and prevention of preeclampsia.

Long Noncoding RNA in Preeclampsia: Transcriptional Noise or Innovative Indicators?

Preeclampsia (PE) is termed as an obstetric issue that is characterized by hypertension (≧140/90 mm Hg), together with proteinuria following 20 weeks of pregnancy. Until today, PE still constitutes a severe threat to the lives of both the mothers and fetuses. In the past, long noncoding RNAs (lncRNAs) were considered as the transcriptional noise. However, some investigations have indicated that lncRNAs could be used as innovative indicators in PE. The current review aims to discuss the relationship between lncRNAs and PE in recent years. According to the retrieved data, we concluded that lncRNAs can exert an impact on both the occurrence and development of PE through the changes in the biological functions of trophoblasts, immune regulation, epigenetic regulation, decidualization, and energy metabolism. The mechanisms of lncRNAs in PE will help us to better understand the pathogenesis of PE and help us to find targets for predicting and diagnosing PE in the future.

Association of antenatal depression with oxidative stress and impact on spontaneous preterm birth

OBJECTIVE

To determine whether antenatal depression is associated with oxidative stress and inflammation, and secondarily, whether the association between antenatal depression and spontaneous preterm birth (SPTB) is mediated by these biomarkers.

STUDY DESIGN

The primary outcome included urine oxidative stress biomarkers 8-hydroxydeoxyguanosine (8-OHdG) and 8-isoprostane and plasma inflammatory biomarkers measured at 10, 18, and 26 weeks and averaged within individual. Linear and logistic regression models were used, adjusting for age, race, parity, and pre-pregnancy body mass index.

RESULTS

Among 462 women, 8-isoprostane was higher among depressed women (geometric mean: 299.96 pg/mL vs. 237.01 pg/mL; p = 0.001). In multivariable analyses, antenatal depression was significantly associated with an increase in average 8-isoprostane (β: 0.25; 95% CI: 0.05-0.44; p = 0.01). The association of antenatal depression with SPTB was partially mediated by 8-isoprostane. Antenatal depression was not associated with 8-OHdG or inflammatory biomarkers.

CONCLUSIONS

Antenatal depression was associated with higher oxidative stress across pregnancy, namely 8-isoprostane, and may impact SPTB via oxidative stress.

Investigation of elevation as a risk factor for hypertensive disorders of pregnancy among Colorado women between 2007 and 2015

OBJECTIVE

The purpose of this study is to determine the association between high elevation and hypertensive disorders of pregnancy (HDP).

METHODS

Retrospective cohort study using Colorado birth certificate data to compare HDP at high (≥8,000 ft), moderate (4,501-7,999 ft), or low (≤4,500 ft) elevation using logistic regression.

RESULTS

Among the cohort (n = 314,431), 3.4% of women developed a HDP. High or moderate elevation was not significantly associated with HDP relative to low elevation (adjusted odds ratio [aOR] 1.16, 95% confidence interval [CI] 0.93-1.43; aOR 1.14, 95% CI 0.98-1.31, respectively).

CONCLUSION

Women living at high or moderate elevation do not have higher odds of HDP.

Screening for spontaneous preterm birth and resultant therapies to reduce neonatal morbidity and mortality: A review

Despite considerable effort aimed at decreasing the incidence of spontaneous preterm birth, it remains the leading cause of perinatal morbidity and mortality. Screening strategies are imperfect. Approaches used to identify women considered by historical factors to be low risk for preterm delivery (generally considered to be women with singleton pregnancies without a history of a previous preterm birth) as well as those at high risk for preterm birth (those with a previous preterm birth, short cervix, or multiple gestation) continue to evolve. Herein, we review the current evidence and approaches to screening women for preterm birth, and examine future directions for clinical practice. Further research is necessary to better identify at-risk women and provide evidence-based management.

Long Non-Coding RNAs Serve as Diagnostic Biomarkers of Preeclampsia and Modulate Migration and Invasiveness of Trophoblast Cells

Background

Long non-coding RNAs (lncRNAs) have emerged as crucial regulators of tumor progression. However, the effects of lncRNAs in preeclampsia are not entirely clear. The aim of this study was to demonstrate the potential of lncRNAs to serve as biomarkers in preeclampsia.

Material/Methods

The RNA expression levels of lncRNAs (NR_027457, BC030099, AF037219, NR_024178, AF085938, G43016, G36948, NR_029420, NR_024015, AK002210, NR_026643, and AL049277) in the serum of patients with preeclampsia and in the serum of normal controls were measured by qRT-PCR. The area under the curve (AUC), the optimal cut-off values, the specificity, and the sensitivity of NR_027457, AF085938, G36948, and AK002210 were analyzed by receiver operating characteristic (ROC) curve analysis. We designed RNA interference species to suppress NR_027457 and G36948 and identified the roles of NR_027457 and G36948 in the functions of a trophoblast cell line (HTR-8/SVneo).

Results

The qRT-PCR results indicated that NR_027457 and AF085938 were significantly up-regulated, whereas G36948 and AK002210 were significantly down-regulated in preeclampsia. We found that NR_027457, AF085938, G36948, and AK002210 had potential diagnostic value for the detection of preeclampsia. Furthermore, the levels of NR_027457, AF085938, G36948, and AK002210 in the serum of patients were significantly different before vs. after surgery. The silencing of NR_027457 inhibited the proliferation, migration, and invasion abilities of HTR-8/SVneo cells, while the silencing of G36948 promoted the proliferation, migration, and invasion abilities of HTR-8/SVneo cells.

Conclusions

NR_027457, AF085938, G36948, and AK002210 can serve as potential diagnostic biomarkers in preeclampsia, and NR_027457 and G36948 might be involved in the pathogenesis of preeclampsia.

Synergistic effect of DDT and its metabolites in lipopolysaccharide-mediated TNF-α production is inhibited by progesterone in peripheral blood mononuclear cells

Increased TNF-α levels have been associated with adverse pregnancy outcomes. Lipopolysaccharide (LPS), 1,1,1-trichloro-2,2-bis-(chlorophenyl)ethane (DDT), 1,1-bis-(chlorophenyl)-2,2-dichloroethene (DDE), and 1,1-dichloro-2,2-bis(chlorophenyl)ethane (DDD) induce TNF-α release in peripheral blood mononuclear cells (PBMC). Conversely, progesterone (P4) inhibits TNF-α secretion. Pregnant women in malaria endemic areas may be co-exposure to these compounds. Thus, this study was to investigate the synergistic effect of LPS and these pesticides in PBMC and to assess P4 influence on this synergy. Cultured PBMC were exposed to each pesticide in the presence of LPS, P4, or their combination. TNF-α was measured by ELISA. All pesticides enhanced TNF-α synthesis in PBMC. Co-exposure with LPS synergizes TNF-α production, which is blocked by progesterone. These results indicate that these organochlorines act synergistically with LPS to induce TNF-α secretion in PBMC. This effect is blocked by P4.

Development and validation of a spontaneous preterm delivery predictor in asymptomatic women

BACKGROUND

Preterm delivery remains the leading cause of perinatal mortality. Risk factors and biomarkers have traditionally failed to identify the majority of preterm deliveries.

OBJECTIVE

To develop and validate a mass spectrometry-based serum test to predict spontaneous preterm delivery in asymptomatic pregnant women.

STUDY DESIGN

A total of 5501 pregnant women were enrolled between 17(0/7) and 28(6/7) weeks gestational age in the prospective Proteomic Assessment of Preterm Risk study at 11 sites in the United States between 2011 and 2013. Maternal blood was collected at enrollment and outcomes collected following delivery. Maternal serum was processed by a proteomic workflow, and proteins were quantified by multiple reaction monitoring mass spectrometry. The discovery and verification process identified 2 serum proteins, insulin-like growth factor-binding protein 4 (IBP4) and sex hormone-binding globulin (SHBG), as predictors of spontaneous preterm delivery. We evaluated a predictor using the log ratio of the measures of IBP4 and SHBG (IBP4/SHBG) in a clinical validation study to classify spontaneous preterm delivery cases (<37(0/7) weeks gestational age) in a nested case-control cohort different from subjects used in discovery and verification. Strict blinding and independent statistical analyses were employed.

RESULTS

The predictor had an area under the receiver operating characteristic curve value of 0.75 and sensitivity and specificity of 0.75 and 0.74, respectively. The IBP4/SHBG predictor at this sensitivity and specificity had an odds ratio of 5.04 for spontaneous preterm delivery. Accuracy of the IBP4/SHBG predictor increased using earlier case-vs-control gestational age cutoffs (eg, <35(0/7) vs ≥35(0/7) weeks gestational age). Importantly, higher-risk subjects defined by the IBP4/SHBG predictor score generally gave birth earlier than lower-risk subjects.

CONCLUSION

A serum-based molecular predictor identifies asymptomatic pregnant women at risk of spontaneous preterm delivery, which may provide utility in identifying women at risk at an early stage of pregnancy to allow for clinical intervention. This early detection would guide enhanced levels of care and accelerate development of clinical strategies to prevent preterm delivery.

Can microRNA profiling in maternal blood identify women at risk for preterm birth?

OBJECTIVE

MicroRNAs (miRNAs), which are highly conserved single-stranded noncoding RNAs that play a crucial role in gene regulation, have now been identified as important players in many diseases states. MiRNAs have also been demonstrated to be reliable and useful biomarkers to identify those women who are at risk for specific adverse outcomes. The objective of this study was to determine whether miRNA profiles in maternal blood are different in women who are destined to have a preterm, compared with a term, birth.

STUDY DESIGN

A nested case-control study was performed with maternal serum that was collected as part of a larger prospective cohort. MiRNA expression profiles in maternal serum were compared between women who ultimately had a preterm birth (n = 40) compared with term birth (n = 40). MiRNA expression profiles were created with the use of the Affymetrix GeneChip miRNA Array. The data were analyzed with the significance of analysis of microarrays and principle components analyses. A false discovery rate of 20% was used to determine the most differentially expressed miRNAs.

RESULTS

Of the 5640 miRNAs that were analyzed on the array, 4 miRNAs were significantly different between cases and control subjects. Two of the 4 miRNAs were mature miRNAs. The fold difference in expression was <2 for all 4 miRNAs.

CONCLUSION

MiRNA profiles in maternal blood were not significantly different in women who were destined to have a preterm, compared with a term, birth. MiRNAs in maternal blood are unlikely to become clinically useful biomarkers for the prediction of preterm birth.

Brachial Artery Flow Mediated Dilation in the First Trimester to Predict the Occurrence of Hypertensive Disorders during Pregnancy

Objectives: To determine whether brachial artery flow-mediated dilation (FMD) assessed by ultrasonography during the late first trimester is able to predict the occurrence of hypertensive disorders during pregnancy. Methods: Maternal endothelial function was assessed by flow-mediated dilation (FMD) of the brachial artery in 487 pregnant women at 11-13+6 weeks' gestation. Subjects were prospectively followed and grouped according to the outcomes related to hypertensive disorders. We determined the areas under receiver operating characteristic (ROC) curve with their respective 95% confidence intervals (CI) for using low FMD results to predict the occurrence of hypertensive disorders during pregnancy. Results: Among 487 women, 9 (1.8%) were diagnosed with early-onset preeclampsia, 22 (4.5%) were diagnosed with late-onset preeclampsia, 47 (9.7%) developed gestational hypertension, and the remaining 409 (84%) pregnancies were unaffected by hypertensive disorders. Area under ROC curve analyses demonstrated that FMD was not able to predict pregnancies that developed hypertensive disorders. Conclusions: We conclude that FMD should not be considered a potential first-trimester marker of hypertensive disorders during pregnancy.

Statistical methods for modeling repeated measures of maternal environmental exposure biomarkers during pregnancy in association with preterm birth

BACKGROUND

It is of critical importance to evaluate the role of environmental chemical exposures in premature birth. While a number of studies investigate this relationship, most utilize single exposure measurements during pregnancy in association with the outcome. The studies with repeated measures of exposure during pregnancy employ primarily cross-sectional analyses that may not be fully leveraging the power and additional information that the data provide.

METHODS

We examine 9 statistical methods that may be utilized to estimate the relationship between a longitudinal exposure and a binary, non-time-varying outcome. To exemplify these methods we utilized data from a nested case-control study examining repeated measures of urinary phthalate metabolites during pregnancy in association with preterm birth.

RESULTS

The methods summarized may be useful for: 1) Examining sensitive windows of exposure in association with an outcome; 2) Summarizing repeated measures to estimate the relationship between average exposure and an outcome; 3) Identifying acute exposures that may be relevant to the outcome; and 4) Understanding the contribution of temporal patterns in exposure levels to the outcome of interest. In the study of phthalates, changes in urinary metabolites over pregnancy did not appear to contribute significantly to preterm birth, making summary of average exposure across gestation optimal given the current design.

CONCLUSIONS

The methods exemplified may be of great use in future epidemiologic research projects intended to: 1) Elucidate the complex relationships between environmental chemical exposures and preterm birth; 2) Investigate biological mechanisms in prematurity using repeated measures of maternal factors throughout pregnancy; and 3) More generally, address the relationship between a longitudinal predictor and a binary, non-time-varying outcome.

The development of partnership after hypertensive diseases in pregnancy

OBJECTIVE

Hypertensive diseases in pregnancy (HDP) occur in 5-8% of all pregnancies and represent one of the most important causes of maternal and fetal morbidity. Even after a normal pregnancy/delivery adaptation to parenthood is a major challenge. However, a successful adjustment is important for future family health. As pregnancy complications may put additional strain on early parenthood, the current study investigated satisfaction with partnership including factors which determine (dis)satisfaction as well as separation rates after pregnancies complicated by HDP.

METHODS

A total of 737 women after HDP and 624 matched-control women completed a self-administered questionnaire on psycho-social factors in the development of HDP. Free-text answers on satisfaction with partnership were analyzed by conceptual analysis.

RESULTS

Women with HDP were significantly less often satisfied with their partnership than control women (76%/81.1%; p < 0.05). Women with preeclampsia were at higher risk for an unsatisfactory relationship than those with other manifestations of HDP. Common interests and aims could be identified as the most important reasons for a satisfying marital relationship in women with and without a diagnosis of HDP.

CONCLUSION

HDP represent an additional challenge in family adjustment. Adapted perinatal psycho-social support may help to facilitate the start into family life.

Multivariate adaptive regression splines analysis to predict biomarkers of spontaneous preterm birth

OBJECTIVE

To develop classification models of demographic/clinical factors and biomarker data from spontaneous preterm birth in African Americans and Caucasians.

DESIGN

Secondary analysis of biomarker data using multivariate adaptive regression splines (MARS), a supervised machine learning algorithm method.

SETTING

Analysis of data on 36 biomarkers from 191 women was reduced by MARS to develop predictive models for preterm birth in African Americans and Caucasians.

SAMPLES

Maternal plasma, cord plasma collected at admission for preterm or term labor and amniotic fluid at delivery.

METHODS

Data were partitioned into training and testing sets. Variable importance, a relative indicator (0-100%) and area under the receiver operating characteristic curve (AUC) characterized results.

RESULTS

Multivariate adaptive regression splines generated models for combined and racially stratified biomarker data. Clinical and demographic data did not contribute to the model. Racial stratification of data produced distinct models in all three compartments. In African Americans maternal plasma samples IL-1RA, TNF-α, angiopoietin 2, TNFRI, IL-5, MIP1α, IL-1β and TGF-α modeled preterm birth (AUC train: 0.98, AUC test: 0.86). In Caucasians TNFR1, ICAM-1 and IL-1RA contributed to the model (AUC train: 0.84, AUC test: 0.68). African Americans cord plasma samples produced IL-12P70, IL-8 (AUC train: 0.82, AUC test: 0.66). Cord plasma in Caucasians modeled IGFII, PDGFBB, TGF-β1 , IL-12P70, and TIMP1 (AUC train: 0.99, AUC test: 0.82). Amniotic fluid in African Americans modeled FasL, TNFRII, RANTES, KGF, IGFI (AUC train: 0.95, AUC test: 0.89) and in Caucasians, TNF-α, MCP3, TGF-β3 , TNFR1 and angiopoietin 2 (AUC train: 0.94 AUC test: 0.79).

CONCLUSIONS

Multivariate adaptive regression splines models multiple biomarkers associated with preterm birth and demonstrated racial disparity.

Longitudinal profiling of inflammatory cytokines and C-reactive protein during uncomplicated and preterm pregnancy

PROBLEM

Previous studies have investigated the utility of inflammation markers as predictors of preterm birth, but none have compared trends in levels between uncomplicated and preterm pregnancy.

METHOD OF STUDY

We explored longitudinal changes in plasma cytokines, including IL-1β, IL-6, IL-10, and TNF-α, as well as C-reactive protein in pregnant women from a nested case-control study.

RESULTS

IL-6 was associated with increased odds of spontaneous preterm birth, defined by presentation of spontaneous preterm labor and/or preterm premature rupture of the membranes. Associations were strongest later in pregnancy. IL-10 was associated with increased odds of placentally mediated preterm birth, defined by presentation with preeclampsia or intrauterine growth restriction, and odds ratios were also highest near the end of pregnancy.

CONCLUSION

Maternal inflammation markers were associated with increased risk of preterm birth, and relationships differed by etiology of preterm delivery and gestational age at sample collection.

Amniotic fluid metabolomic analysis in spontaneous preterm birth

OBJECTIVE

To identify metabolic changes associated with early spontaneous preterm birth (PTB; <34 weeks) and term births, using high-throughput metabolomics of amniotic fluid (AF) in African American population.

METHOD

In this study, AF samples retrieved from spontaneous PTB (<34 weeks [n = 25]) and normal term birth (n = 25) by transvaginal amniocentesis at the time of labor prior to delivery were subjected to metabolomics analysis. Equal volumes of samples were subjected to a standard solvent extraction method and analyzed using gas chromatography/mass spectrometry (MS) and liquid chromatography/MS/MS. Biochemicals were identified through matching of ion features to a library of biochemical standards. After log transformation and imputation of minimum observed values for each compound, t test, correlation tests, and false discovery rate corrections were used to identify differentially regulated metabolites. Data were controlled for clinical/demographic variables and medication during pregnancy.

RESULTS

Of 348 metabolites measured in AF samples, 121 metabolites had a gestational age effect and 116 differed significantly between PTB and term births. A majority of significantly altered metabolites could be classified into 3 categories, namely, (1) liver function, (2) fatty acid and coenzyme A (CoA) metabolism, and (3) histidine metabolism. The signature of altered liver function was apparent in many cytochrome P450-related pathways including bile acids, steroids, xanthines, heme, and phase II detoxification of xenobiotics with the largest fold change seen with pantothenol, a CoA synthesis inhibitor that was 8-fold more abundant in PTB.

CONCLUSION

Global metabolic profiling of AF revealed alteration in hepatic metabolites involving xenobiotic detoxification and CoA metabolism in PTB. Maternal and/or fetal hepatic function differences may be developmentally related and its contribution PTB as a cause or effect of PTB is still unclear.

Proteomic biomarkers for spontaneous preterm birth: a systematic review of the literature

This review aimed to identify, synthesize, and analyze the findings of studies on proteomic biomarkers for spontaneous preterm birth (PTB). Three electronic databases (Medline, Embase, and Scopus) were searched for studies in any language reporting the use of proteomic biomarkers for PTB published between January 1994 and December 2012. Retrieved citations were screened, and relevant studies were selected for full-text reading, in triplicate. The search yielded 529 citations, 51 were selected for full-text reading and 8 studies were included in the review. A total of 64 dysregulated proteins were reported. Only 14-3-3 protein sigma, annexin A5, protein S100-A8, protein S100-A12, and inter-α-trypsin inhibitor heavy chain H4 were reported in more than 1 study, but results could not be combined due to heterogeneity in type of sample and analytical platform. In conclusion, according to the existing literature, there are no specific proteomic biomarkers capable of accurately predicting PTB.