Evidence from human placenta, ER-stressed trophoblasts and transgenic mice links transthyretin proteinopathy to preeclampsia

We have demonstrated that protein aggregation plays a pivotal role in the pathophysiology of preeclampsia (PE) and identified several aggregated proteins in the circulation of PE patients, most significantly the serum protein transthyretin (TTR). Here we show robust accumulation of TTR aggregates in the placentas of women with early-onset PE (e-PE). TTR aggregation was inducible in primary human trophoblasts (PHTs) and the TCL-1 trophoblast cell line by ER stress inducers or autophagy-lysosomal disruptors. Hypoxia/reoxygenation (H/R) of cultured PHTs increased intracellular BiP, phosphorylated IRE1alpha, PDI and Ero-1, all markers of the UPR, and the apoptosis mediator caspase-3. Blockade of IRE1alpha inhibited H/R-induced upregulation of Ero-1 in PHTs. Excessive UPR was observed in the PE placenta. Further, pregnant mice, overexpressing transgene encoded wild type human TTR, displayed aggregated TTR in the junctional zone of the placenta and PE-like features including hypertension, proteinuria, intrauterine growth restriction, kidney injury, and elevated levels of the PE biomarkers serum sFlt-1 and endoglin. High Resolution Ultrasound analysis revealed low blood flow in uterine and umbilical arteries compared to that found in wild type pregnant mice. On the other hand, loss of mouse TTR function did not cause any pregnancy abnormalities in Ttr-/- mice. These observations in the PE placenta, cultured trophoblast cells and TTR transgenic mice indicate that TTR aggregation is an important causal contributor to PE pathophysiology.

Comparison of Diagnostic Values of Maternal Arginine Concentration for Different Pregnancy Complications: A Systematic Review and Meta-Analysis

Abnormal arginine metabolism contributes to the development of intrauterine growth restriction (IUGR), preeclampsia (PE), and gestational diabetes mellitus (GDM), which increase the health burden of mothers and induce adverse birth outcomes. However, associations between maternal arginine concentration and different pregnancy complications have not been systematically compared. The PubMed, ScienceDirect, and Web of Science databases were searched for peer-reviewed publications to evaluate the diagnostic value of plasma arginine concentration in complicated pregnancies. Standardized mean difference (SMD) of the arginine concentration was pooled by a random effects model. The results show that increased maternal arginine concentrations were observed in IUGR (SMD: 0.48; 95% CI: 0.20, 0.76; I2 = 47.0%) and GDM (SMD: 0.46; 95% CI: 0.11, 0.81; I2 = 82.3%) cases but not in PE patients (SMD: 0.21; 95% CI: −0.04, 0.47; I2 = 80.3%) compared with the normal cohorts. Subgroup analyses indicated that the non-fasting circulating arginine concentration in third trimester was increased significantly in GDM and severe IUGR pregnancies, but the change mode was dependent on ethnicity. Additionally, only severe PE persons were accompanied by higher plasma arginine concentrations. These findings suggest that maternal arginine concentration is an important reference for assessing the development of pregnancy complications.

Co-expression analysis of placental genes in the search for key signaling pathways and biomarkers of the great obstetrical syndromes

Objective. To study the molecular mechanisms responsible for the development of diseases grouped within the great obstetrical syndromes (GOS) at the level of the transcriptome of human maternal placenta.Material and Methods. We gathered the results of genome-wide transcriptome studies of the human placental tissue using Gene Expression Omnibus (GEO) data repository for the following phenotypes: physiological pregnancy, preeclampsia (PE), premature birth, and intrauterine growth restriction (IUGR). Eleven data sets were selected and supplemented with our experimental data; a total of 481 samples of human placental tissue were included in the integrative analysis. Bioinformatic data processing and statistical analyses were performed in the R v3.6.1 software environment using the Bioconductor packages. The pooled dataset was used to search for common molecular targets for GOS via weighted gene co-expression network analysis (WGCNA). The functional annotation of genes and the resulting clusters was carried out with the DAVID database; protein-protein interaction network was built using the STRING software; and the hub genes for the network were identified using the MCC analysis with plugin cytoHubba in Cytoscape software 3.7.2.Results. We obtained a table of expression levels for 15,167 genes in 246 samples. Hierarchical clustering of this network allowed to find 55 modules of co-expressed genes in the group with PE, 109 modules in the group with PB, 75 modules in patients with IUGR, and 56 modules in the control group. The preservation analysis of co-expressed modules for the studied phenotypes suggested the presence of a common cluster comprising eight genes specific only for patients with PE and IUGR, as well as the module of 23 co-expressed genes typical only for patients with PB and IUGR. Protein-protein interaction network was built for these gene sets, and the SOD1, TXNRD1, and UBB genes were the central nodes in the network. Based on network topology evaluation with cytoHubba, six hub genes (rank ˂ 5) were identified as follows: SOD1, TKT, TXNRD1, GCLM, GOT1, and ACO1.Conclusion. The obtained results allowed to identify promising genetic markers for preeclampsia, intrauterine growth restriction, and miscarriage. Moreover, the study also made it possible to identify the most important overlapping molecular mechanisms of these diseases occurring in the placental tissue.

Intrauterine growth restriction disrupts the postnatal critical period of synaptic plasticity in the mouse dorsal hippocampus in a model of hypertensive disease of pregnancy

Introduction: Intrauterine growth restriction (IUGR) from hypertensive disease of pregnancy complicates up to 10% of all pregnancies. Significant hippocampal-dependent cognitive and memory impairments as well as neuropsychiatric disorders have been linked to IUGR. Because disturbance of hippocampal critical period (CPd) of synaptic plasticity leads to impairments similar to those described in IUGR human offspring, we hypothesized that IUGR would perturb the CPd of synaptic plasticity in the mouse hippocampus in our model. Methods: IUGR was produced by a micro-osmotic pump infusion of the potent vasoconstrictor U-46619, a thromboxane A2-agonist (TXA2), at embryonic day (E) 12.5 in C57BL/6J mouse dams to precipitate hypertensive disease of pregnancy and IUGR. Sham-operated mice acted as controls. At P10, P18, and P40, we assessed astrogliosis using GFAP-IHC. In dorsal CA1 and CA3 subfields, we assessed the immunoreactivities (IR) (IF-IHC) to: i) parvalbumin (PV) and glutamate decarboxylase (GAD) 65/67, involved in CPd onset; ii) PSA-NCAM, that antagonizes CPd onset; iii) NPTX2, necessary for excitatory synapse formation and engagement of CPd; and iv) MBP and WFA, staining perineural nets (PNNs), marking CPd closure. ImageJ/Fiji and IMARIS were used for image processing and SPSS v24 for statistical analysis. Results: Although PV+ interneuron (IN) numbers and IR intensity were unchanged, development of GAD65/67+ synaptic boutons was accelerated at P18 IUGR mice, and inversely correlated with decreased expression of PSA-NCAM in the CA of P18 IUGR mice at P18. NPTX2 + puncta and total volume were persistently decreased in the CA3 pyramidal and radiatum layers of IUGR mice from P18 to P40. At P40, axonal myelination (MBP+) in CA3 of IUGR mice was decreased and correlated with NPTX2 deficits. Lastly, the volume and integrity of the PNNs in the dorsal CA was disrupted in IUGR mice at P40. Discussion/Conclusion: IUGR disrupts the molecular and structural initiation, consolidation and closure of the CPd of synaptic plasticity in the mouse hippocampus in our model, which may explain the learning and memory deficits observed in juvenile IUGR mice and the cognitive disorders seen in human IUGR offspring. The mechanistic links warrant further investigation, to identify therapeutic targets to prevent neurodevelopmental deficits in patients affected by IUGR.

Relationship between Twin-to-Twin Selective Intrauterine Growth Restriction with sFas/sFasL Level of Umbilical Cord Blood Using Doppler Ultrasound Fetal Heart Rhythm Detection Algorithm

The study focused on the application value of ultrasound Doppler fetal heart rate detection algorithm based on short-time Fourier transform (STFT) in the diagnosis of twin-to-twin selective intrauterine growth restriction (sIUGR) and the correlation between twin-to-twin sIUGR and sFas/sFasL levels of umbilical cord blood. The normalized method was introduced into the STFT algorithm to optimize it to detect the fetal instantaneous heart rate. 82 pregnant women with twin pregnancies were selected as the research subjects and they were divided into the restricted group (41 cases) and the control group (41 cases) according to whether the fetus had selective growth restriction. The two groups were compared for the differences in the fetal mortality, complication rate, and sFas/sFasL expression levels. The results showed that the STFT-based ultrasonic Doppler fetal heart rate detection algorithm could ensure the quality of the fetal heart rate signal and had high resolution at the 200–400 Hz characteristic frequency band and that the accuracy in distinguishing S1 and S2 was 5.8% higher than that of the traditional autocorrelation algorithm. The proportion of abnormal fetal heart rate in the restricted group was significantly higher than that in the control group ( P < 0.05 ), birth weight was significantly lower than that in the control group ( P < 0.05 ), and fetal mortality was significantly higher than that in the control group ( P < 0.05 ). There was no statistical difference in the incidence of complications between the two groups ( P > 0.05 ). In restricted group, the content of sFas in cord blood was (3326.54 ± 317.42) pg/mL and that in the control group was (2003.29 ± 196.45) pg/mL. The content of sFas in cord blood of the restricted group was significantly higher than that of the control group ( P < 0.01 ). In the restricted group, the content of sFasL in cord blood was (382.52 ± 36.17) pg/mL, and that in the control group was (180.84 ± 16.20) pg/mL. The content of sFasL in cord blood of the restricted group was significantly higher than that of the control group ( P < 0.001 ). It was concluded that the STFT-based ultrasound Doppler fetal heart rate monitoring is beneficial to early diagnosis and timely intervention of twin-to-twin sIUGR.