Collaboration to Understand Complex Diseases

Prospecting of exosomal-miRNA signatures as prognostic marker for gestational diabetes mellitus and other adverse pregnancy outcomes

Exosomal microRNA (ExomiRs) serves as potential cargo molecules responsible for post-translation of gene expression and intracellular communication playing a vital role in acting as clinically relevant prognostic biomarkers for identifying pregnancy-associated complications in patients. ExomiRs are associated with Gestational Diabetes Mellitus (GDM) as potential targets for understanding the pathophysiology of beta-cell dysfunction. ExomiRs (ExomiR 122, ExomiR 16-5p, ExomiR 215-5p, ExomiR 450b-3p, ExomiR 122-5p) aid to act as biomarkers and regulate the progression of diabetes and its related complication. These ExomiRshave been reported to interfere with the regulation of various genes such as ZEB2, IRS1, IRS2, GLUT1, GLUT4, etc. and inhibition of several pathways like PI3K/AKT, Wnt, and mTOR signaling pathways leading to the modulation in the development of GDM affecting the clinical and pathological features of women. These ExomiRs have also been associated with other pregnancy-associated complications, including preeclampsia, hypothyroidism, pregnancy loss, and ectopic pregnancies. On the other hand, overexpression of certain ExomiRs such as Exomir-515-5p, ExomiR-221, and ExomiR-96 serve a regulatory role in overcoming insulin resistance. Taken together, the current review focuses on the prospective capabilities of ExomiRs for diagnosis and clinical prognosis of GDM women with respect to pregnancy outcomes.

What a paediatric nephrologist should know about preeclampsia and why it matters

Preeclampsia is a protean syndrome causing a kidney disease characterised by hypertension and proteinuria, usually considered transitory and reversible after delivery. Its prevalence ranges from 3-5 to 10% if all the related disorders are considered. This narrative review, on behalf of the Kidney and Pregnancy Study Group of the Italian Society of Nephrology, focuses on three reasons why preeclampsia should concern paediatric nephrologists and how they can play an important role in its prevention, as well as in the prevention of future kidney and cardiovascular diseases. Firstly, all diseases of the kidney and urinary tract diagnosed in paediatric age are associated with a higher risk of adverse pregnancy-related outcomes, including preeclampsia. Secondly, babies with low birth weights (small for gestational age, born preterm, or both) have an increased risk of developing the full panoply of metabolic diseases (obesity, hypertension, early-onset cardiopathy and chronic kidney disease) and girls are at higher risk of developing preeclampsia when pregnant. The risk may be particularly high in cases of maternal preeclampsia, highlighting a familial aggregation of this condition. Thirdly, pregnant teenagers have a higher risk of developing preeclampsia and the hypertensive disorders of pregnancy, and should be followed up as high risk pregnancies. In summary, preeclampsia has come to be seen as a window on the future health of both mother and baby. Identification of subjects at risk, early counselling and careful follow-up can contribute to reducing the high morbidity linked with this disorder.

Vision for Improving Pregnancy Health: Innovation and the Future of Pregnancy Research

Understanding, predicting, and preventing pregnancy disorders have been a major research target. Nonetheless, the lack of progress is illustrated by research results related to preeclampsia and other hypertensive pregnancy disorders. These remain a major cause of maternal and infant mortality worldwide. There is a general consensus that the rate of progress toward understanding pregnancy disorders lags behind progress in other aspects of human health. In this presentation, we advance an explanation for this failure and suggest solutions. We propose that progress has been impeded by narrowly focused research training and limited imagination and innovation, resulting in the failure to think beyond conventional research approaches and analytical strategies. Investigations have been largely limited to hypothesis-generating approaches constrained by attempts to force poorly defined complex disorders into a single "unifying" hypothesis. Future progress could be accelerated by rethinking this approach. We advise taking advantage of innovative approaches that will generate new research strategies for investigating pregnancy abnormalities. Studies should begin before conception, assessing pregnancy longitudinally, before, during, and after pregnancy. Pregnancy disorders should be defined by pathophysiology rather than phenotype, and state of the art agnostic assessment of data should be adopted to generate new ideas. Taking advantage of new approaches mandates emphasizing innovation, inclusion of large datasets, and use of state of the art experimental and analytical techniques. A revolution in understanding pregnancy-associated disorders will depend on networks of scientists who are driven by an intense biological curiosity, a team spirit, and the tools to make new discoveries.

The prediction of preeclampsia: the way forward

Despite intensive investigation, we still cannot adequately predict, treat, or prevent preeclampsia. We have gained awareness that preeclampsia is a syndrome not a disease and is heterogeneous in its presentation and pathophysiology, which may indicate differing underlying phenotypes, and that the impact extends beyond pregnancy per se. Effects on the fetus and mother extend many years after pregnancy, as evidenced by fetal programming of adult disease and increased risk of the development of maternal cardiovascular disease. The increased occurrence of preeclampsia in women with preexisting risk factors suggests that the stress of pregnancy may expose subclinical vascular disease as opposed to preeclampsia damaging the vasculature. The heterogeneity of preeclampsia has blighted efforts to predict preeclampsia early in gestation and has thwarted success in attempts at therapy with treatments, such as low-dose aspirin or global antioxidants. There is a critical need to identify the phenotypes to enable their specific prediction and treatment. Such studies require considerably larger collections of patients than employed in past and current studies. This does not necessarily imply much larger patient numbers in single studies but can be facilitated by the ability to easily combine many smaller studies. This can be accomplished by agreeing on a priori standardized and harmonized clinical data and biospecimen collection across new studies. Such standards are being established by international groups of investigators. Leadership by international organizations, perhaps adopting a carrot and stick approach, to overcome investigator, institutional and funder reticence toward data sharing is required to ensure adoption of such standards. Future studies should include women in both low- and high-resource settings and employ social media and novel methods for data collection and analysis, including machine learning and artificial intelligence. The goal is to identify the pathophysiology underlying differing preeclampsia phenotypes, their successful prediction with the design, and the implementation of phenotype-specific therapies.

Syncytiotrophoblast stress in preeclampsia: the convergence point for multiple pathways

Preeclampsia evolves in 2 stages: a placental problem that generates signals to the mother to cause a range of responses that comprise the second stage (preeclampsia syndrome). The first stage of early-onset preeclampsia is poor placentation, which we here call malplacentation. The spiral arteries are incompletely remodeled, leading to later placental malperfusion, relatively early in the second half of pregnancy. The long duration of the first stage (several months) is unsurprisingly associated with fetal growth restriction. The first stage of late-onset preeclampsia, approximately 80% of total cases, is shorter (several weeks) and part of a process that is common to all pregnancies. Placental function declines as it outgrows uterine capacity, with increasing chorionic villous packing, compression of the intervillous space, and fetal hypoxia, and causes late-onset clinical presentations such as "unexplained" stillbirths, late-onset fetal growth restriction, or preeclampsia. The second stages of early- and late-onset preeclampsia share syncytiotrophoblast stress as the most relevant feature that causes the maternal syndrome. Syncytiotrophoblast stress signals in the maternal circulation are probably the most specific biomarkers for preeclampsia. In addition, soluble fms-like tyrosine kinase-1 (mainly produced by syncytiotrophoblast) is the best-known biomarker and is routinely used in clinical practice in many locations. How the stress signals change over time in normal pregnancies indicates that syncytiotrophoblast stress begins on average at 30 to 32 weeks' gestation and progresses to term. At term, syncytiotrophoblast shows increasing markers of stress, including apoptosis, pyroptosis, autophagy, syncytial knots, and necrosis. We label this phenotype the "twilight placenta" and argue that it accounts for the clinical problems of postmature pregnancies. Senescence as a stress response differs in multinuclear syncytiotrophoblast from that of mononuclear cells. Syncytiotrophoblast irreversibly acquires part of the senescence phenotype (cell cycle arrest) when it is formed by cell fusion. The 2 pathways converge on the common pathologic endpoint, syncytiotrophoblast stress, and contribute to preeclampsia subtypes. We highlight that the well-known heterogeneity of the preeclampsia syndrome arises from different pathways to this common endpoint, influenced by maternal genetics, epigenetics, lifestyle, and environmental factors with different fetal and maternal responses to the ensuing insults. This complexity mandates a reassessment of our approach to predicting and preventing preeclampsia, and we summarize research priorities to maximize what we can learn about these important issues.

Long noncoding RNA SNHG12 promotes the proliferation, migration, and invasion of trophoblast cells by regulating the epithelial-mesenchymal transition and cell cycle

Objective

The deficient placental blood perfusion caused by the attenuated infiltration of trophoblast cells is a key factor in the occurrence of preeclampsia (PE). Furthermore, the long noncoding (lnc)RNA SNHG12 (small nucleolar RNA host gene 12) can promote the proliferation and metastasis of multiple tumor cells. However, whether lncRNA SNHG12 affects proliferation and metastasis of trophoblast cells is unclear.

Methods

We examined the level of lncRNA SNHG12 in plasma and placenta of patients with PE and constructed trophoblast cells with overexpressed or knocked down SNHG12. CCK-8, wound healing, and Transwell assays were used to detect alterations in proliferation, migration, and invasion of trophoblast cells. Western blotting was used to detect proteins related to the epithelial–mesenchymal transition (EMT), and cell cycle assays clarified cell cycle distribution.

Results

LncRNA SNHG12 promoted the proliferation, migration, and invasion of trophoblast cells. The expression of matrix metalloproteinase-2 (MMP-2) and MMP-9, β-catenin, and vimentin were positively correlated with SNHG12, and expression of E-cadherin was negatively correlated with SNHG12. SNHG12 also promoted the transition of trophoblast cells from G₀/G₁ to S phase.

Conclusion

Overall, lncRNA SNHG12 promoted the migration and invasion of trophoblast cells by inducing the progression of EMT.

Subtypes of Preeclampsia: Recognition and Determining Clinical Usefulness

The concept that preeclampsia is a multisystemic syndrome is appreciated in both research and clinical care. Our understanding of pathophysiology recognizes the role of inflammation, oxidative and endoplasm reticulum stress, and angiogenic dysfunction. Yet, we have not progressed greatly toward clinically useful prediction nor had substantial success in prevention or treatment. One possibility is that the maternal syndrome may be reached through different pathophysiological pathways, that is, subtypes of preeclampsia, that in their specificity yield more clinical utility. For example, early and late onset preeclampsia are increasingly acknowledged as different pathophysiological processes leading to a common presentation. Other subtypes of preeclampsia are supported by disparate clinical outcomes, long-range prognosis, organ systems involved, and risk factors. These insights have been supplemented by discovery-driven methods, which cluster preeclampsia cases into groups indicating different pathophysiologies. In this presentation, we review likely subtypes based on current knowledge and suggest others. We present a consideration of the requirements for a clinically meaningful preeclampsia subtype. A useful subtype should (1) identify a specific pathophysiological pathway or (2) specifically indicate maternal or fetal outcome, (3) be recognizable in a clinically useful time frame, and (4) these results should be reproducible and generalizable (but at varying frequency) including in low resource settings. We recommend that the default consideration be that preeclampsia includes several subtypes rather than trying to force all cases into a single pathophysiological pathway. The recognition of subtypes and deciphering their different pathophysiologies will provide specific targets for prevention, prediction, and treatment directing personalized care.

Differences in Placental Imprinted Gene Expression across Preeclamptic and Non-Preeclamptic Pregnancies

Preeclampsia is a multi-systemic syndrome that presents in approximately 5% of pregnancies worldwide and is associated with a range of subsequent postpartum and postnatal outcomes, including fetal growth restriction. As the placenta plays a critical role in the development of preeclampsia, surveying genomic features of the placenta, including expression of imprinted genes, may reveal molecular markers that can further refine subtypes to aid targeted disease management. In this study, we conducted a comprehensive survey of placental imprinted gene expression across early and late onset preeclampsia cases and preterm and term normotensive controls. Placentas were collected at delivery from women recruited at the Magee-Womens Hospital prenatal clinics, and expression levels were profiled across 109 imprinted genes. We observed downregulation of placental Mesoderm-specific transcript (MEST) and Necdin (NDN) gene expression levels (false discovery rate (FDR) < 0.05) among early onset preeclampsia cases compared to preterm controls. No differences in placental imprinted gene expression were observed between late onset preeclampsia cases and term controls. While few studies have linked NDN to pregnancy complications, reductions in MEST expression levels, as observed in our study, are consistently reported in the literature in relation to various pregnancy complications, including fetal growth restriction, suggesting a potential role for placental MEST expression as a biosensor of an adverse in utero environment.

Brazilian Maternal and Child Nutrition Consortium: establishment, data harmonization and basic characteristics

Pooled data analysis in the field of maternal and child nutrition rarely incorporates data from low- and middle-income countries and existing studies lack a description of the methods used to harmonize the data and to assess heterogeneity. We describe the creation of the Brazilian Maternal and Child Nutrition Consortium dataset, from multiple pooled longitudinal studies, having gestational weight gain (GWG) as an example. Investigators of the eligible studies published from 1990 to 2018 were invited to participate. We conducted consistency analysis, identified outliers, and assessed heterogeneity for GWG. Outliers identification considered the longitudinal nature of the data. Heterogeneity was performed adjusting multilevel models. We identified 68 studies and invited 59 for this initiative. Data from 29 studies were received, 21 were retained for analysis, resulting in a final sample of 17,344 women with 72,616 weight measurements. Fewer than 1% of all weight measurements were flagged as outliers. Women with pre-pregnancy obesity had lower values for GWG throughout pregnancy. GWG, birth length and weight were similar across the studies and remarkably similar to a Brazilian nationwide study. Pooled data analyses can increase the potential of addressing important questions regarding maternal and child health, especially in countries where research investment is limited.

Cardiometabolic Risk Factors in Pregnancy and Implications for Long-Term Health: Identifying the Research Priorities for Low-Resource Settings

Cardiometabolic disorders (CMDs), including ischemic heart disease, stroke and type 2 diabetes are the leading causes of mortality and morbidity in women worldwide. The burden of CMDs falls disproportionately on low and middle-income countries (LMICs), placing substantial demands on already pressured health systems. Cardiometabolic disorders may present up to a decade earlier in some LMIC settings, and are associated with high-case fatality rates. Early identification and ongoing postpartum follow-up of women with pregnancy complications such as hypertensive disorders of pregnancy (HDPs), and gestational diabetes mellitus (GDM) may offer opportunities for prevention, or help delay onset of CMDs. This mini-review paper presents an overview of the key challenges faced in the early identification, referral and management of pregnant women at increased risk of CMDs, in low-resource settings worldwide. Evidence-based strategies, including novel diagnostics, technology and innovations for early detection, screening and management for pregnant women at high-risk of CMDs are presented. The review highlights the key research priorities for addressing cardiometabolic risk in pregnancy in low-resource settings.

A Method for Analyzing Two-locus Epistasis of Complex Diseases based on Decision Tree and Mutual Entropy

Background:

Epistasis makes complex diseases difficult to understand, especially when heterogeneity also exists. Heterogeneity of complex diseases makes the distribution of case population more confused. However, the traditional methods proposed to detect epistasis often ignore heterogeneity, resulting in low power of association studies.

Methods:

In this study, we firstly use rank information in the Classification Decision Tree and Mutual Entropy (CTME) to construct two different evaluation scores, namely multiple objectives. In addition, we improve the calculation of joint entropy between SNPs and disease label, which elevates the efficiency of CTME. Then, the ant colony algorithm is applied to search two-locus epistatic combination space. To handle the potential heterogeneity, all candidate two-locus SNPs are merged to recognize multiple different epistatic combinations. Finally, all these solutions are tested by χ2 test.

Results and Conclusion:

Experiments show that our method CTME improves the power of association study. More importantly, CTME also detects multiple epistatic SNPs contributing to heterogeneity. The experimental results show that CTME has advantages on power and efficiency.

Impact of Arginine Nutrition and Metabolism during Pregnancy on Offspring Outcomes

By serving as a precursor for the synthesis of nitric oxide, polyamines, and other molecules with biological importance, arginine plays a key role in pregnancy and fetal development. Arginine supplementation is a potential therapy for treating many human diseases. An impaired arginine metabolic pathway during gestation might produce long-term morphological or functional changes in the offspring, namely, developmental programming to increase vulnerability to developing a variety of non-communicable diseases (NCDs) in later life. In contrast, reprogramming is a strategy that shifts therapeutic interventions from adulthood to early-life, in order to reverse the programming processes, which might counterbalance the rising epidemic of NCDs. This review presented the role of arginine synthesis and metabolism in pregnancy. We also provided evidence for the links between an impaired arginine metabolic pathway and the pathogenesis of compromised pregnancy and fetal programming. This was followed by reprogramming strategies targeting the arginine metabolic pathway, to prevent the developmental programming of NCDs. Despite emerging evidence from experimental studies showing that targeting the arginine metabolic pathway has promise as a reprogramming strategy in pregnancy to prevent NCDs in the offspring, these results need further clinical application.

Giants in Obstetrics and Gynecology Series: A profile of James M. Roberts, MD

Dr. James Roberts has made seminal contributions to the understanding of the physiology of pregnancy, and, in particular, to the mechanisms of disease responsible for preeclampsia. His research includes endothelial cell dysfunction, oxidative stress, and other factors that play a role in the pathogenesis of preeclampsia; the use of antioxidant therapy to prevent the syndrome; identification of clinical subtypes of preeclampsia; and assessment of the long-term cardiovascular risk of the disorder. Dr. Roberts is currently an investigator at the Magee-Womens Research Institute and a Professor of Obstetrics, Gynecology, and Reproductive Sciences, Endocrinology, and Clinical and Translational Medicine at the University of Pittsburgh. He was the founding Director of the Magee-Womens Research Institute, and formerly the Elsie Hilliard Hillman Chair in Women’s and Infants’ Health Research at the University of Pittsburgh. For his many original contributions to the understanding of preeclampsia and other obstetrical syndromes, Dr. Roberts is herein recognized as a “Giant in Obstetrics and Gynecology.”

A systematic review and meta-analysis indicates long-term risk of chronic and end-stage kidney disease after preeclampsia

Preeclampsia is a pregnancy-related syndrome of variable severity, classically characterized by acute kidney involvement, with hypertension and/or proteinuria and reduced kidney function. Once considered a self-limited disease healed by delivery, it is now acknowledged that preeclampsia can affect cardiovascular and kidney health in the long term. The entity of risk has not been established and consequently follow-up policies have not been defined. Here we undertook a systematic review to gain better insights into the need for post-preeclampsia follow-up. Articles published between January 2000 and March 2018 were selected, dealing with at least 20 preeclampsia patients, with follow-up of 4 years or more (MEDLINE, Embase, and Cochrane Library). No quality selection or language restriction was performed. Of the 10,510 titles and abstracts originally considered, 21 papers were selected, providing information on 110,803 cases with and 2,680,929 controls without preeclampsia, with partial overlap between studies on the same databases. Heterogeneity was high, and a random meta-analytic model selected. The increase in risk of end stage renal disease after preeclampsia was significant (meta-analytic risk ratios (95% confidence interval) 6.35 (2.73-14.79)); the risk of albuminuria and chronic kidney disease increased but statistical significance was not reached (4.31 (0.95-19.58) and 2.03 (0.58-7.32), respectively). Translating meta-analytic risk into the number of patients who need follow-up to detect one adverse event, 310 patients with preeclampsia are needed to identify one woman with end stage renal disease or four to identify one woman with albuminuria. Heterogeneity in definitions, insufficient follow-up and incomplete recruitment may account for discrepancies. Thus, preeclampsia significantly increases the risk of end stage renal disease. However, there is lack of sufficient data to show a relationship between preeclampsia, albuminuria and chronic kidney disease, underlining the need for further prospective studies.

Electronic Algorithm Is Superior to Hospital Discharge Codes for Diagnoses of Hypertensive Disorders of Pregnancy in Historical Cohorts

OBJECTIVES

To develop and validate criteria for the retrospective diagnoses of hypertensive disorders of pregnancy that would be amenable to the development of an electronic algorithm, and to compare the accuracy of diagnoses based on both the algorithm and diagnostic codes with the gold standard, of physician-made diagnoses based on a detailed review of medical records using accepted clinical criteria.

PATIENTS AND METHODS

An algorithm for hypertensive disorders of pregnancy was developed by first defining a set of criteria for retrospective diagnoses, which included relevant clinical variables and diagnosis of hypertension that required blood pressure elevations in greater than 50% of readings ("the 50% rule"). The algorithm was validated using the Rochester Epidemiology Project (Rochester, Minnesota). A stratified random sample of pregnancies and deliveries between January 1, 1976, and December 31, 1982, with the algorithm-based diagnoses was generated for review and physician-made diagnoses (normotensive, gestational hypertension, and preeclampsia), which served as the gold standard; the targeted cohort size for analysis was 25 per diagnosis category according to the gold standard. Agreements between (1) algorithm-based diagnoses and (2) diagnostic codes and the gold standard were analyzed.

RESULTS

Sensitivities of the algorithm for 25 normotensive pregnancies, 25 with gestational hypertension, and 25 with preeclampsia were 100%, 88%, and 100%, respectively, and specificities were 94%, 100%, and 100%, respectively. Diagnostic code sensitivities were 96% for normotensive pregnancies, 32% for gestational hypertension, and 96% for preeclampsia, and specificities were 78%, 96%, and 88%, respectively.

CONCLUSION

The electronic diagnostic algorithm was highly sensitive and specific in identifying and classifying hypertensive disorders of pregnancy and was superior to diagnostic codes.

The complex aetiology of cerebral palsy

Cerebral palsy (CP) is the most prevalent, severe and costly motor disability of childhood. Consequently, CP is a public health priority for prevention, but its aetiology has proved complex. In this Review, we summarize the evidence for a decline in the birth prevalence of CP in some high-income nations, describe the epidemiological evidence for risk factors, such as preterm delivery and fetal growth restriction, genetics, pregnancy infection and other exposures, and discuss the success achieved so far in prevention through the use of magnesium sulfate in preterm labour and therapeutic hypothermia for birth-asphyxiated infants. We also consider the complexities of disentangling prenatal and perinatal influences, and of establishing subtypes of the disorder, with a view to accelerating the translation of evidence into the development of strategies for the prevention of CP.

Dynamics of Renin, Angiotensin II, and Angiotensin (1-7) during Pregnancy and Predisposition to Hypertension-Associated Complications

Changes in the levels of rennin, angiotensin II, and angiotensin (1-7) were studied during normal pregnancy. The blood was taken on gestation days 140-237 and 238-280. No significant changes in renin concentration were observed during normal pregnancy (p=0.423). The level of angiotensin II increased during normal pregnancy from 9.7±1.2 to 14.7±1.9 pg/ml (p=0.019). On the contrary, angiotensin (1-7) concentration decreased from 771.1±44.2 to 390.7±13.9 pg/ml (p<0.001). The shift in the proportion between vasoconstrictor angiotensin II and vasodilaltor angiotensin (1-7) attests to high predisposition of pregnant women to hypertension-related complications.

The perplexing pregnancy disorder preeclampsia: what next?

Preeclampsia occurs in 3–5% of pregnancies and is a leading cause of deaths of mothers and their infants worldwide. It was initially described over 100 yr ago as a pregnancy abnormality defined by new-onset hypertension and proteinuria. Progress in understanding the pathophysiology was impeded by attention to these diagnostic findings. Hypertension and proteinuria were actually serendipitously recognized components of a complex multisystemic syndrome and not especially pertinent to outcome. With the recognition of inflammatory activation with consequent endothelial dysfunction 30 yr ago redirection of research resulted in an explosive increase in understanding of the disorder. The immunological origins, the role of the placenta and its functional alterations due to endoplasmic reticulum and oxidative stress, identification of placental products linking placental dysfunction to maternal systemic pathophysiology, and the role of the maternal constitution have been elegantly demonstrated by clinical, fundamental, and epidemiological findings and clever animal experimentation. Nonetheless, this increase in knowledge has not translated into improved prediction and prevention of preeclampsia. In this presentation the likelihood is discussed that this is secondary to a much greater complexity than has been previously considered and the existence of subtypes of preeclampsia that may not share an identical pathophysiology. The necessity for collaboration with data, sample, and intellectual sharing is addressed. An approach to addressing the challenges posed to such collaboration exemplified by the Global Pregnancy Collaboration is presented.

Subclinical First Trimester Renal Abnormalities Are Associated With Preeclampsia in Normoalbuminuric Women With Type 1 Diabetes

OBJECTIVE

This study was conducted to determine the utility of tubular (urinary/plasma neutrophil gelatinase-associated lipocalin [NGAL] and urinary kidney injury molecule 1 [KIM-1]) and glomerular (estimated glomerular filtration rate [eGFR]) biomarkers in predicting preeclampsia (PE) in pregnant women with type 1 diabetes mellitus (T1DM) who were free of microalbuminuria and hypertension at the first trimester.

RESEARCH DESIGN AND METHODS

This was a prospective study of T1DM pregnancy. Maternal urinary and plasma NGAL, urinary KIM-1 (ELISA of frozen samples), and eGFR (Chronic Kidney Disease Epidemiology Collaboration equation) were determined at three study visits (V1: 12.4 ± 1.8; V2: 21.7 ± 1.4; V3: 31.4 ± 1.5 weeks' gestation [mean ± SD]) in 23 women with T1DM with subsequent PE (DM+PE+), 24 who remained normotensive (DM+PE-), and, for reference, in 19 normotensive pregnant women without diabetes (DM-). The groups with diabetes were matched for age, diabetes duration, and parity. All subjects were normotensive and free of microalbuminuria or albuminuria at V1. All study visits preceded the onset of PE.

RESULTS

Urinary creatinine-corrected NGAL (uNGALcc, ng/mg) was significantly elevated at V1 in DM+PE+ vs. DM+PE- women (P = 0.01); this remained significant after exclusion of leukocyte-positive samples (5 DM+PE+ and 2 DM+PE-) (P = 0.02). Accounting for BMI, HbA_1c, and total daily insulin dose, a doubling of uNGALcc at V1 conferred a sevenfold increase in risk for PE (P = 0.026). In contrast, neither plasma NGAL nor urinary KIM-1 predicted PE. Also at V1, eGFR was elevated in DM+PE+ vs. DM+PE- (P = 0.04).

CONCLUSIONS

Early tubular and glomerular dysfunction may predict PE in first trimester women with T1DM, even if free of microalbuminuria. These data suggest that subclinical renal tubular and glomerular injury, if present early in pregnancy, may predispose women with T1DM to PE.

Translational Systems Pharmacology Studies in Pregnant Women

Pregnancy involves rapid physiological adaptation and complex interplay between mother and fetus. New analytic technologies provide large amounts of genomic, proteomic, and metabolomics data. The integration of these data through bioinformatics, statistical, and systems pharmacology techniques can improve our understanding of the mechanisms of normal maternal physiologic changes and fetal development. New insights into the mechanisms of pregnancy‐related disorders, such as preterm birth (PTB), may lead to the development of new therapeutic interventions and novel biomarkers.

Oxidative Stress in the Rostral Ventrolateral Medulla Contributes To Cardiovascular Regulation in Preeclampsia

Background: It has been demonstrated that preeclampsia, a pregnancy-specific hypertension disorder, is characterized by high blood pressure (BP) and sympathetic overactivity. Increased reactive oxygen species (ROS) in the rostral ventrolateral medulla (RVLM), a key region for controlling sympathetic tone, has been reported to contribute to high level of BP and sympathetic outflow. The aim of the present study was to determine the role of the RVLM ROS in mediating the preeclampsia-associated cardiovascular dysfunction.

Methods: The animal model of preeclampsia was produced by administration of desoxycorticosterone acetate (DOCA) to pregnant rats.

Results: Compared with normal pregnant rats without DOCA treatment (NP), the protein concentration and norepinephrine excretion in 24-h urine, as well as BP in pregnant rats with DOCA treatment (PDS) were significantly increased. The levels of superoxide anion and the protein expression of NADPH oxidase subtype (NOX4) in the RVLM were significantly increased in PDS than in NP groups. Furthermore, microinjection of the superoxide dismutase (SOD) mimic Tempol (5 nmol) into the RVLM significantly decreased BP, heart rate, and renal sympathetic never activity in PDS but not in NP group.

Conclusion: The present data suggest that high BP and sympathetic overactivity in preeclampsia rats is associated with increased oxidative stress in the RVLM via upregulation of NOX4 expression.

Availability of COLLECT, a database for pregnancy and placental research studies worldwide

Cost and availability of a database often impede research while the lack of compatibility inhibits collaboration by making merging of databases difficult or impossible. The Global Pregnancy Collaboration (CoLab) has promoted harmonization of studies and standardized data collection to facilitate pregnancy and placental research. Its online database, COLLECT, allows collection of minimal and optimal clinical datasets to accompany basic and applied science studies and provides a placental sample inventory system. COLLECT is available free of charge in LMIC and for $100 per month in HIC. Data is the property of the investigator but with permission can be combined into larger studies across centers and countries.

•

High quality clinical data can usefully assist basic placental research studies.

•

Designing a database is expensive and existing databases are usually incompatible.

•

CoLab has designed and made available a tried and tested database at low or no cost.

•

Data is the property of the investigator but can be easily combined with permission.

Elevated Adenosine Induces Placental DNA Hypomethylation Independent of A2B Receptor Signaling in Preeclampsia

Preeclampsia is a prevalent pregnancy hypertensive disease with both maternal and fetal morbidity and mortality. Emerging evidence indicates that global placental DNA hypomethylation is observed in patients with preeclampsia and is linked to altered gene expression and disease development. However, the molecular basis underlying placental epigenetic changes in preeclampsia remains unclear. Using 2 independent experimental models of preeclampsia, adenosine deaminase-deficient mice and a pathogenic autoantibody-induced mouse model of preeclampsia, we demonstrate that elevated placental adenosine not only induces hallmark features of preeclampsia but also causes placental DNA hypomethylation. The use of genetic approaches to express an adenosine deaminase minigene specifically in placentas, or adenosine deaminase enzyme replacement therapy, restored placental adenosine to normal levels, attenuated preeclampsia features, and abolished placental DNA hypomethylation in adenosine deaminase-deficient mice. Genetic deletion of CD73 (an ectonucleotidase that converts AMP to adenosine) prevented the elevation of placental adenosine in the autoantibody-induced preeclampsia mouse model and ameliorated preeclampsia features and placental DNA hypomethylation. Immunohistochemical studies revealed that elevated placental adenosine-mediated DNA hypomethylation predominantly occurs in spongiotrophoblasts and labyrinthine trophoblasts and that this effect is independent of A2B adenosine receptor activation in both preeclampsia models. Extending our mouse findings to humans, we used cultured human trophoblasts to demonstrate that adenosine functions intracellularly and induces DNA hypomethylation without A2B adenosine receptor activation. Altogether, both mouse and human studies reveal novel mechanisms underlying placental DNA hypomethylation and potential therapeutic approaches for preeclampsia.

A best practice position statement on the role of the nephrologist in the prevention and follow-up of preeclampsia: the Italian study group on kidney and pregnancy

Preeclampsia (PE) is a protean syndrome causing a transitory kidney disease, characterised by hypertension and proteinuria, ultimately reversible after delivery. Its prevalence is variously estimated, from 3 to 5% to 10% if all the related disorders, including also pregnancy-induced hypertension (PIH) and HELLP syndrome (haemolysis, increase in liver enzyme, low platelets) are included. Both nephrologists and obstetricians are involved in the management of the disease, according to different protocols, and the clinical management, as well as the role for each specialty, differs worldwide. The increased awareness of the role of chronic kidney disease in pregnancy, complicating up to 3% of pregnancies, and the knowledge that PE is associated with an increased risk for development of CKD later in life have recently increased the interest and redesigned the role of the nephrologists in this context. However, while the heterogeneous definitions of PE, its recent reclassification, an emerging role for biochemical biomarkers, the growing body of epidemiological data and the new potential therapeutic interventions lead to counsel long-term follow-up, the lack of resources for chronic patients and the increasing costs of care limit the potential for preventive actions, and suggest tailoring specific interventional strategies. The aim of the present position statement of the Kidney and Pregnancy Study Group of the Italian Society of Nephrology is to review the literature and to try to identify theoretical and pragmatic bases for an agreed management of PE in the nephrological setting, with particular attention to the prevention of the syndrome (recurrent PE, presence of baseline CKD) and to the organization of the postpartum follow-up.

Cohort profile: the Finnish Genetics of Pre-eclampsia Consortium (FINNPEC)

PURPOSE

The Finnish Genetics of Pre-eclampsia Consortium (FINNPEC) Study was established to set up a nationwide clinical and DNA database on women with and without pre-eclampsia (PE), including their partners and infants, in order to identify genetic risk factors for PE.

PARTICIPANTS

FINNPEC is a cross-sectional case-control cohort collected from 5 university hospitals in Finland during 2008-2011. A total of 1450 patients with PE and 1065 pregnant control women without PE (aged 18-47 years) were recruited. Altogether, there were 1377 full triads (625 PE and 752 control triads).

FINDINGS TO DATE

The established cohort holds both clinical and genetic information of mother-infant-father triads representing a valuable resource for studying the pathogenesis of the disease. Furthermore, maternal biological samples (first and third trimester serum and placenta) will provide additional information for PE research. Until now, research has encompassed studies on candidate genes, Sanger and next-generation sequencing, and various studies on the placenta. FINNPEC has also participated in the InterPregGen study, which is the largest investigation on maternal and fetal genetic factors underlying PE until now.

FUTURE PLANS

Ongoing studies focus on elucidating the role of immunogenetic and metabolic factors in PE. Data on morbidity and mortality will be collected from mothers and fathers through links to the nationwide health registers.