Brain Vascular Dysfunction in Mothers and Their Children Exposed to Preeclampsia

Brain and brain blood vessels histological description in autopsies of fetuses/neonates born to mothers with hypertension during pregnancy. A case-control study

Background

Children born to women with hypertension during pregnancy have a two to threefold increased risk of developing cognitive disorders compared to children born to women without hypertension. However, structural changes in the central nervous system of these children remain poorly understood. We aim to compare the brain histological findings from autopsies of neonates and fetuses born to women with and without hypertension during pregnancy.

Methods

This retrospective case-control study includes brain histological samples from autopsies of neonates and fetuses born to women with (n = 22) and without (n = 15) hypertension during pregnancy, obtained from biobanks associated with the University Hospital San Ignacio (HUSI), Bogotá, Colombia, between 2007 and 2022. Hypertension during pregnancy was diagnosed following American College of Obstetricians and Gynecologists (ACOG) guidelines. Matched criteria included similar maternal pre-pregnancy morbidity, gestational ages at delivery, fetal sex, and availability of similar histological samples of fetal/neonatal brains. Clinical data were recorded, and two diagnosed-blinded pathologists analyzed all slides.

Findings

Ninety-three percent (14/15) of fetuses/neonates born to women with hypertension during pregnancy were born after preeclamptic pregnancies. Histological findings were described for the frontotemporal cortex (97%, 36/37) and meninges (81%, 30/37). Fetuses/neonates born to women with hypertension during pregnancy were smaller (p = 0.030), had a lower gestational age at death (p = 0.047), and were more frequently stillborn. Autopsy records revealed higher maternal vascular malperfusion in women with hypertension during pregnancy (p < 0.0001). Subarachnoid hemorrhage was more common in fetuses/neonates born to women with hypertension during pregnancy (p = 0.036). Other frequent findings included neuropil edema, congested meninges, hypoxic-ischemic encephalopathy, subdural hematoma, venous sinus thrombosis, hemoventricle, and necrotic foci. However, no significant endothelial or vascular wall changes were noted. "Prominent and congested" capillaries were observed only in fetuses/neonates born to women without hypertension.

Interpretation

The findings suggest increased cerebrovascular vulnerability in fetuses and neonates exposed to maternal hypertension during pregnancy, with a higher incidence of subarachnoid hemorrhage. While no vascular wall changes were identified, fewer brain capillary alterations were noted in those born to women with hypertension during pregnancy.

Funding

Fondecyt 1200250, 1240295.

Extracellular Vesicles From Preeclampsia Disrupt the Blood-Brain Barrier by Reducing CLDN5

BACKGROUND

The physiopathology of life-threatening cerebrovascular complications in preeclampsia is unknown. We investigated whether disruption of the blood-brain barrier, generated using circulating small extracellular vesicles (sEVs) from women with preeclampsia or placentae cultured under hypoxic conditions, impairs the expression of tight junction proteins, such as CLDN5 (claudin-5), mediated by VEGF (vascular endothelial growth factor), and activation of KDR (VEGFR2 [VEGF receptor 2]).

METHODS

We perform a preclinical mechanistic study using sEVs isolated from plasma of pregnant women with normal pregnancy (sEVs-NP; n=9), sEVs isolated from plasma of women with preeclampsia (sEVs-PE; n=9), or sEVs isolated from placentas cultured in normoxia (sEVs-Nor; n=10) or sEVs isolated from placentas cultured in hypoxia (sEVs-Hyp; n=10). The integrity of the blood-brain barrier was evaluated using in vitro (human [hCMEC/D3] and mouse [BEND/3] brain endothelial cell lines) and in vivo (nonpregnant C57BL/6J mice [4-5 months old; n=13] injected with sEVs-Hyp) models.

RESULTS

sEVs-PE and sEVs-Hyp reduced total and membrane-associated protein CLDN5 levels (P<0.05). These results were negated with sEVs-PE sonication. sEVs-Hyp injected into nonpregnant mice generated neurological deficits and blood-brain barrier disruption, specifically in the posterior area of the brain, associated with brain endothelial cell uptake of sEVs, sEVs-Hyp high extravasation, and reduction in CLDN5 levels in the brain cortex. Furthermore, sEVs-PE and sEVs-sHyp had higher VEGF levels than sEVs-NP and sEVs-Nor. Human brain endothelial cells exposed to sEVs-PE exhibited a reduction in the activation of KDR. Reduction in CLDN5 observed in cells treated with sEVs-Hyp was further enhanced in cells treated with KDR selective inhibitor.

CONCLUSIONS

sEVs-PE disrupts the blood-brain barrier, an effect replicated with sEVs-Hyp, and involves reduced CLDN5 and elevated VEGF contained within these vesicles. However, our results do not support the participation of KDR activation in the downregulation of CLDN5 observed with sEVs-Hyp. These findings will improve our understanding of the pathophysiology of cerebrovascular alterations in women with preeclampsia.

Assessment of attention-deficit / hyperactivity disorder signs among Palestinian school-age children

PURPOSE

The study aimed to identify the prevalence of Attention-Deficit / Hyperactivity Disorder (ADHD) signs exhibited in Palestinian school-age students while comparing their sociodemographic characteristics.

DESIGN AND METHODS

A cross-sectional descriptive correlation study was conducted. The study included children aged 6-12 in West Bank schools, without a previous ADHD diagnoses or other neurodevelopmental disorders. This study used a parent questionnaire with three sections: child's sociodemographic data, parents' data, and Vanderbilt ADHD Diagnostic Parent Rating Scale (VADPRS), which has a Cronbach's alpha values of 0.94 for total ADHD. All collected data were analyzed using SPSS version 25, with confidence interval of 95 %.

RESULTS

A total 487 school-aged children participated in the study (46.4 % females and 53.6 % males). The results showed that 8.7 % of the children exhibited ADHD signs, with ADHD-I being the most prevalent subtype (3.3 %). Significant associations were found between ADHD signs and the following factors: males (P = 0.003); children with lower academic averages (less than 79.9 %) (P = 0.000); children speaking only one language (P = 0.002); children of mothers exposed to tobacco during pregnancy (P = 0.004); children whose mothers faced complications during pregnancy (P = 0.000); children whose mothers were 19 years old or younger at childbirth scores (P = 0.05); and children with relatives having ADHD (P = 0.000). No significant associations were found with variables such as child's age, birth weight, gestational age, number of countries lived in, school class, place of residency, parents' marital status, educational level, employment status, average income, number of children, or child's birth order. A moderate negative correlation was found between ADHD signs and poor academic performance (r = -0.169, P = 0.000).

CONCLUSION

The study found a significant prevalence of ADHD signs in Palestinian school-age children (8.7 %), with ADHD-I having the highest prevalence. Risk factors included gender, languages, maternal exposure to tobacco, maternal complications, mother's age, and relatives with ADHD. Early detection is crucial to mitigate its impact on academic performance.

PRACTICE IMPLICATIONS

Nurses play a crucial role in managing ADHD in school-aged children. They conduct educational programs, early screening programs, and work with a multidisciplinary team to evaluate and monitor suspected ADHD cases. They also advocate for research and policy development to improve ADHD care and outcomes. This ensures children receive necessary treatment and support services.

Intrauterine growth-restricted pregnant rats, from placental ischemic dams, display preeclamptic-like symptoms: A new rat model of preeclampsia

Preeclampsia (PE) is characterized by de novo hypertension (HTN) and is often associated with intrauterine growth restriction (IUGR). Hallmarks of PE are placental ischemia, decreased nitric oxide (NO) bioavailability, oxidative stress (OS), and organ damage in the kidneys and brain. This study aims to characterize a new model of PE using pregnant IUGR rats from hypertensive placental ischemic dams. It is hypothesized that pregnant IUGR rats from hypertensive placental ischemic dams will have elevated blood pressure (BP), OS, and organ damage. In this study, pregnant rats are divided into two groups: normal pregnant (NP) and hypertensive placental ischemic dams (RUPP). Offspring from NP and RUPP dams were mated at 10 weeks of age to generate pregnant IUGR (IUGR Preg) and pregnant control (CON Preg) rats. BP and other markers of PE were evaluated during late gestation. Pregnant IUGR rats had elevated BP and systemic OS. The maternal body weight of pregnant IUGR rats and their pups' weights were decreased, while the brains were enlarged with elevated OS. In summary, pregnant IUGR rats, born from hypertensive placental ischemic dams, have HTN and increased systemic and brain OS, with larger brain sizes and smaller pups. Furthermore, this study shows that pregnant IUGR rats exhibit a preeclamptic-like phenotype, suggesting a new epigenetic model of PE.

Bidirectional Mendelian Randomization Analysis of Genetic Proxies of Plasma Fatty Acids and Pre-Eclampsia Risk

BACKGROUND

Previous studies have reported associations between fatty acids and the risk of pre-eclampsia. However, the causality of these associations remains uncertain. This study postulates a causal relationship between specific plasma fatty acids and pre-eclampsia or other maternal hypertensive disorders (PE-HTPs). To test this hypothesis, two-sample bidirectional Mendelian randomization (MR) analyses were employed to determine the causality effects.

METHODS

Single-nucleotide polymorphisms associated with PE-HTPs and fatty acids were obtained from a genome-wide association study (GWAS) of European ancestry. Bidirectional MR analyses were conducted using methods such as inverse variance weighted, MR-Egger, weighted median, simple mode, and weighted mode. Sensitivity analyses, including tests for heterogeneity, horizontal pleiotropy, and co-localization, were conducted to assess the robustness of MR results.

RESULTS

The analyses revealed causal relationships between PE-HTPs and several fatty acids, including monounsaturated fatty acid (MUFA), omega-6 fatty acid (n-6 FA), linoleic acid (LA), docosahexaenoic acid (DHA), and the PUFA/MUFA ratio. Genetically predicted higher risk of PE-HTPs was significantly associated with lower plasma n-6 FA (OR = 0.96, 95% CI: 0.93-0.99), particularly LA (OR = 0.95, 95% CI: 0.92-0.98). Conversely, increased DHA (OR = 0.86, 95% CI: 0.78-0.96) and a higher PUFA/MUFA ratio (OR = 0.86, 95% CI: 0.76-0.98) were associated with a reduced risk of PE-HTPs. Elevated MUFA levels (OR = 1.12, 95% CI: 1.00-1.25) were related to an increased risk.

CONCLUSIONS

This study provides robust genetic evidence supporting bidirectional causal relationships between PE-HTPs and specific plasma fatty acids, underscoring the critical role of fatty acid metabolism in maternal hypertensive disorders.

Factors Associated with Maternal Morbidity in Patients with Eclampsia in Three Obstetric Intensive Care Units: A Retrospective Study

(1) Introduction. Eclampsia is a rare complication that can occur during pregnancy and has a significant impact on maternal and neonatal outcomes. The aim of this study was to investigate the risk factors associated with significant maternal morbidity after an eclamptic seizure. (2) Methods. An observational retrospective study was performed in three maternity hospitals in Romania between 2015 and 2023 and included pregnant patients diagnosed with eclampsia. Clinical and paraclinical data were investigated, and the impact of several risk factors was assessed using multiple logistic regression analysis. The results were reported as risk ratios (RRs) and 95% confidence intervals (Cis). (3) Results. A total of 104 patients with preeclampsia, of whom 23 experienced eclamptic seizures, were included in this study. A total of 82.6% of the patients diagnosed with eclampsia experienced a form of significant morbidity (stroke, PRES syndrome, or any organ failure/dysfunction). Our regression analysis revealed that advanced maternal age (RR: 12.24 95% CI: 4.29-36.61, p = 0.002), the presence of thrombotic disorders (RR: 9.17, 95% CI: 3.41-23.70, p = 0.03), obesity (RR: 4.89, 95% CI: 0.78-18.15, p = 0.036), and smoking status (RR: 2.18, 95% CI: 0.13- 6.51, p = 0.042) significantly increase the risk of maternal comorbidities. (4) Conclusions. Careful monitoring of pregnant patients, adequate weight control during pregnancy, and correct anticoagulation of individual patients could reduce the extent of postpartum comorbidities that can result from an eclamptic seizure.

Hypertensive disorders of pregnancy and stroke: a univariate and multivariate Mendelian randomization study

Background

Hypertensive disorders of pregnancy (HDP) are associated with an increased risk of stroke later in life in multiparous women. However, causality of these associations remains unclear. This study employed 2-sample univariate and multivariate Mendelian randomization (MR) to assess the causal connection between HDP and stroke.

Methods

Genetic variants for HDP and two subtypes were identified from recent large-scale genome-wide association studies and the FinnGen consortium. Stroke summary data were obtained from the MEGASTROKE consortium. The primary analytical approach for univariate MR was the inverse variance weighting method. Sensitivity analyses incorporated methods such as MR-Egger regression, weighted median, and maximum likelihood to ascertain the robustness of the results. Additionally, multivariable MR analyses were conducted to account for potential associative effects of hypertension and type 2 diabetes.

Results

Genetically predicted HDP was associated with a high risk of large artery atherosclerosis (odds ratio [OR]=1.50, 95% confidence interval [CI]: 1.17-1.91, P=1.13×10-3) and small vessel stroke (OR=1.29, 95% CI: 1.20-1.50, P=1.52×10-3). HDP may also correlate with ischemic stroke (OR=1.13, 95% CI: 1.04-1.23, P=4.99×10-3) and stroke (OR=1.11, 95% CI: 1.03-1.20, P=8.85×10-3). An elevated risk of small vessel stroke (OR=1.20, 95% CI: 1.01-1.43, P=3.74×10-2) and large artery atherosclerosis (OR=1.22, 95% CI: 1.01-1.47, P=4.07×10-2) may be related with genetically predicted susceptibility to gestational hypertension. Genetically predicted susceptibility to preeclampsia or eclampsia may be associated with an increased risk of stroke (OR = 1.10, 95% CI: 1.02-1.19, P = 1.16×10-2) and ischemic stroke (OR = 1.10, 95% CI: 1.02-1.20, P = 1.84×10-2). Type 2 diabetes mellitus and hypertension were identified as significant factors contributing to the association between HDP and stroke.

Conclusions

This study provides genetic evidence supporting an association between HDP and increased stroke risk bolstering HDP as a cerebrovascular risk factor.

Preeclampsia: Short- and Long-Term Effects

Does our time inside the womb predict our future? Evidence suggests that the environment in the womb plays a powerful role in predicting specific adult diseases. The fetus is constantly responding and adapting to the intrauterine environment by a process called programming. Toxic exposures, such as nutritional deficits and hypoxia, can affect fetal development and increase the risk for specific diseases that manifest later in our adult life. Preeclampsia (PE) is one disorder that results in a less-than-optimal environment for the growing fetus. It is pregnancy-specific and defined as new-onset hypertension after 20 weeks' gestation in the presence of maternal multiorgan dysfunction. To the best of our understanding, the pathogenesis is multifactorial and involves dysfunction of the placenta and the vascular, renal, and immunological systems. Treatment options are limited and may result in adverse outcomes for the fetus and newborn. Preeclampsia is a major contributor to perinatal and maternal morbidity and mortality worldwide, thus generating a significant healthcare burden. Research continues to demonstrate that mothers and infants affected by PE are at increased susceptibility to chronic conditions such as cardiovascular, renal, metabolic, and neurological diseases. More efforts are needed to further understand this disease. Efforts to increase awareness will help improve clinical outcomes for both mothers and infants.

Diffusion-Weighted MRI of the Fetal Brain in Fetal Growth Restriction With Maternal Preeclampsia or Gestational Hypertension

BACKGROUND

The fetal neurodevelopmental microstructural alterations of intrauterine exposure to preeclampsia (PE) or gestational hypertension (GH) remain unknown.

PURPOSE

To evaluate the differences in diffusion-weighted imaging (DWI) of the fetal brain between normotensive pregnancies and PE/GH pregnancies, with a focus on PE/GH pregnancies with fetal growth restriction (FGR).

STUDY TYPE

Retrospective matched case-control study.

POPULATION

40 singleton pregnancies with PE/GH complicated by FGR, and 3 paired control groups (PE/GH without FGR, normotensive FGR, normotensive pregnancies) (28-38 gestational weeks).

FIELD STRENGTH/SEQUENCE

DWI with single-shot echo-planar imaging at 1.5 Tesla.

ASSESSMENT

The apparent diffusion coefficient (ADC) values were calculated in the centrum semi-ovale (CSO), parietal white matter (PWM), frontal white matter (FWM), occipital white matter (OWM), temporal white matter (TWM), basal ganglia, thalamus (THAL), pons, and cerebellar hemisphere.

STATISTICAL TESTS

Student t test or Wilcoxon matched test was used to reveal the difference of ADC values among the investigated brain regions. A correlation between gestational age (GA) and ADC values was determined by linear regression analysis.

RESULTS

Compared with fetuses in PE/GH without FGR and those with normotensive pregnancies, fetuses in the PE/GH with FGR group had significantly lower average ADC measurements of supratentorial regions (1.65 ± 0.09 vs. 1.71 ± 0.10 10-3  mm2 /sec; vs. 1.73 ± 0.11 10-3  mm2 /sec, respectively). Regions of significantly decreased ADC values in the fetal brain included CSO, FWM, PWM, OWM, TWM and THAL in cases of PE/GH with FGR. ADC values from supratentorial regions in PE/GH pregnancies were not significantly correlated with GA (P = 0.12, 0.26); however, this trend was statistically significant in the normotensive groups.

DATA CONCLUSION

ADC values may indicate fetal brain developmental alterations in PE/GH with FGR fetuses but more microscopic and morphological studies are necessary to provide additional evidence to offer a different interpretation of this trend in fetal brain.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY STAGE: 3.

Prediction of preeclampsia from retinal fundus images via deep learning in singleton pregnancies: a prospective cohort study

INTRODUCTION

Early prediction of preeclampsia (PE) is of universal importance in controlling the disease process. Our study aimed to assess the feasibility of using retinal fundus images to predict preeclampsia via deep learning in singleton pregnancies.

METHODS

This prospective cohort study was conducted at Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine. Eligible participants included singleton pregnancies who presented for prenatal visits before 14 weeks of gestation from September 1, 2020, to February 1, 2022. Retinal fundus images were obtained using a nonmydriatic digital retinal camera during their initial prenatal visit upon admission before 20 weeks of gestation. In addition, we generated fundus scores, which indicated the predictive value of hypertension, using a hypertension detection model. To evaluate the predictive value of the retinal fundus image-based deep learning algorithm for preeclampsia, we conducted stratified analyses and measured the area under the curve (AUC), sensitivity, and specificity. We then conducted sensitivity analyses for validation.

RESULTS

Our study analyzed a total of 1138 women, 92 pregnancies developed into hypertension disorders of pregnancy (HDP), including 26 cases of gestational hypertension and 66 cases of preeclampsia. The adjusted odds ratio (aOR) of the fundus scores was 2.582 (95% CI, 1.883-3.616; P  < 0.001). Otherwise, in the categories of prepregnancy BMI less than 28.0 and at least 28.0, the aORs were 3.073 (95%CI, 2.265-4.244; P  < 0.001) and 5.866 (95% CI, 3.292-11.531; P  < 0.001). In the categories of maternal age less than 35.0 and at least 35.0, the aORs were 2.845 (95% CI, 1.854-4.463; P  < 0.001) and 2.884 (95% CI, 1.794-4.942; P  < 0.001). The AUC of the fundus score combined with risk factors was 0.883 (sensitivity, 0.722; specificity, 0.934; 95% CI, 0.834-0.932) for predicting preeclampsia.

CONCLUSION

Our study demonstrates that the use of deep learning algorithm-based retinal fundus images offers promising predictive value for the early detection of preeclampsia.