Disrupted balance of angiogenic and antiangiogenic signalings in preeclampsia

DNA methylation-mediated 11βHSD2 downregulation drives the increases in angiotensin-converting enzyme and angiotensin II within preeclamptic placentas

Preeclampsia (PE) is a complex human-specific complication frequently associated with placental pathology. The local renin-angiotensin system (RAS) in the human placenta, which plays a crucial role in regulating placental function, has been extensively documented. Glucocorticoids (GCs) are a class of steroid hormones. PE cases often have abnormalities in GCs levels and placental GCs barrier. Despite extensive speculation, there is currently no robust evidence indicating that GCs regulate placental RAS. This study aims to investigate these potential relationships. Plasma and placental samples were collected from both normal and PE pregnancies. The levels of angiotensin-converting enzyme (ACE), angiotensin II (Ang II), cortisol, and 11β-hydroxysteroid dehydrogenases (11βHSD) were analyzed. In PE placentas, cortisol, ACE, and Ang II levels were elevated, while 11βHSD2 expression was reduced. Interestingly, a positive correlation was observed between ACE and cortisol levels in the placenta. A significant inverse correlation was found between the methylation statuses within the 11βHSD2 gene promoter and its expression, meanwhile, 11βHSD2 expression was negatively correlated with cortisol and ACE levels. In vitro experiments using placental trophoblast cells confirmed that active GCs can stimulate ACE transcription and expression through the GR pathway. Furthermore, 11βHSD2 knockdown could enhance this activating effect. An in vivo study using a rat model of intrauterine GCs overexposure during mid-to-late gestation suggested that excess GCs in utero lead to increased ACE and Ang II levels in the placenta. Collectively, this study provides the first evidence of the relationships between 11βHSD2 expression, GCs barrier, ACE, and Ang II levels in the placenta. It not only contributes to understanding the pathological features of the placental GCs barrier and RAS under PE conditions, also provides important information for revealing the pathological mechanism of PE.

Decreased FGF23 inhibits placental angiogenesis via the ERK1/2-EGR-1 signaling pathway in preeclampsia

PURPOSE

This study aimed to investigate the expression of fibroblast growth factor 23 (FGF23) in pregnant women with preeclampsia and elucidate its role in promoting placental angiogenesis through the ERK1/2-EGR-1 signaling pathway.

METHODS

Serum FGF23 levels were measured by ELISA in healthy pregnant women and patients with preeclampsia during the first, second, and third trimesters of pregnancy. Wound healing, Transwell, and tube formation assays were performed to investigate the effects of FGF23 on cell migration, invasion and tube formation. The expression of vascular endothelial growth factor A (VEGF-A) and its upstream signaling molecules, p-ERK, and EGR-1, in placental tissues was detected by RT-qPCR and western blotting. Additionally, the effect of FGF23 on VEGF-A, p-ERK, and EGR-1 expression was further explored in vitro.

RESULTS

Serum FGF23 levels increased with gestational age. During the third trimester, the control group exhibited a more pronounced increase in FGF23 levels than the preeclampsia group. Administering exogenous FGF23 promoted trophoblast cell migration, invasion and enhanced tube formation in vascular endothelial cells. The expression levels of VEGF-A, p-ERK, and EGR-1 in the placental tissues were significantly lower in the preeclampsia group than in the control group. In vitro experiments confirmed that FGF23 up-regulated VEGF-A expression through the p-ERK/EGR-1 signaling pathway.

CONCLUSION

The serum level of FGF23 decreased in pregnant women with preeclampsia, inhibiting the ERK1/2-EGR-1 pathway and resulting in decreased expression of VEGF-A, thereby inhibiting placental angiogenesis. This could be a potential mechanism involved in the progression of preeclampsia.

Influential Serum Kinases (Non-sFlt-1) and Phosphatases in Preeclampsia-Systemic Review and Metanalysis

The early identification of women with an increased risk of preeclampsia (PE) is desirable, but apart from soluble fms-like tyrosine kinase-1 (sFlt-1), few biomarkers have previously been identified as relevant for predicting preeclampsia. Since kinases and phosphatases regulate critical biological processes and previous evidence suggests a potential role of these molecules in preeclampsia, we performed this systematic review and metanalysis. The objective was to determine if there are kinases and phosphatases whose serum levels are different between women with and without PE, being relevant biomarkers of PE. We followed the recommendations of Cochrane and the Preferred Reported Items for Systematic Reviews and Metanalysis (PRISMA) to perform this study. The MESH terms preeclampsia, kinases, phosphatases, angiopoietins, soluble tyrosine protein kinase receptor (sTIE2), and cellular-mesenchymal-epithelial transition factor (c-MET) were combined to find relevant articles in the PubMed, PROSPERO, and Cochrane databases. Then, a qualitative and quantitative analysis was performed in R Studio software. From 580 abstracts identified, 37 were included in the final analysis, which comprised 24,211 pregnant women (2879 with PE and 21,332 women without PE [HP]. The pooled analysis showed that serum creatine kinase (CK) (SMD: 2.43, CI 95% 0.25-4.62) was significantly higher in PE, whereas sTIE2 and anti-angiogenic factor soluble c-Met (sMet)were significantly lower in PE than in HP (SMD: -0.23, CI95% -0.37 to -0.09; and SMD:0.24, CI95% 0.01-0.47, respectively). Adenosine monophosphate-activated protein kinase (AMPK), angiopoietin-1 (ANG-1), angiopoietin-2 (ANG-2), the ratio angiopoietin-1/angiopoietin-2, acid phosphatase, and alkaline phosphatase were not different between women with PE and HP. In summary CK, sTIE2, and c-MET are relevant biomarkers of PE. It is desirable to incorporate them into current models for PE prediction to evaluate their utility as biomarkers.

Nitroxide-HMP-Protects Human Trophoblast HTR-8/SVneo Cells from H2O2-Induced Oxidative Stress by Reducing the HIF1A Signaling Pathway

Preeclampsia (PE) is a pregnancy-specific syndrome affecting 5-7% of patients. There is no effective treatment available. Early abnormal placental development is associated with oxidative stress (OS) and a release of reactive oxygen species (ROS) in the placenta. This phenomenon leads to downstream signaling, Hypoxia Inducible Factor 1A (HIF1A) stabilization and transcription of the anti-angiogenic factors soluble fms-like tyrosine kinase 1 (sFLT1) and soluble endoglin (sEng), which are known to cause endothelial and trophoblast dysfunction and cardinal features of PE: hypertension, proteinuria and, in severe cases, eclampsia. We tested whether 3-(Hydroxymethyl)-1-oxy-2,2,5,5-tetramethylpyrrolidine (HMP)-a nitroxide-type antioxidant molecule-can reduce placental OS and mitigate PE symptoms in vitro. We induced OS in human trophoblast (HTR-8/SVneo) cells with hydrogen peroxide (H2O2) and assessed whether modulating cell redox function with HMP reduces cell injury, mitochondrial stress and HIF1A and sFLT1 production. Pre-treatment with HMP reduced mitochondrial-derived ROS production, restored LC3B expression and reduced HIF1A and sFLT1 expression in H2O2-exposed HTR-8/SVneo trophoblast cells. HMP improved the mitochondrial electron chain enzyme activity, indicating that a reduction in OS alleviates mitochondrial stress and also reduces anti-angiogenic responses. In reducing placental trophoblast OS, HMP presents a potential novel therapeutic approach for the treatment of PE. Future investigation is warranted regarding the in vivo use of HMP.

Maternal PUFAs, Placental Epigenetics, and Their Relevance to Fetal Growth and Brain Development

Dietary polyunsaturated fatty acids (PUFAs), especially omega-3 (n-3) and n-6 long-chain (LC) PUFAs, are indispensable for the fetus' brain supplied by the placenta. Despite being highly unsaturated, n-3 LCPUFA-docosahexaenoic acid (DHA) plays a protective role as an antioxidant in the brain. Deficiency of DHA during fetal development may cause irreversible damages in neurodevelopment programming. Dietary PUFAs can impact placental structure and functions by regulating early placentation processes, such as angiogenesis. They promote remodeling of uteroplacental architecture to facilitate increased blood flow and surface area for nutrient exchange. The placenta's fatty acid transfer depends on the uteroplacental vascular development, ensuring adequate maternal circulatory fatty acids transport to fulfill the fetus' rapid growth and development requirements. Maternal n-3 PUFA deficiency predominantly leads to placental epigenetic changes than other fetal developing organs. A global shift in DNA methylation possibly transmits epigenetic instability in developing fetuses due to n-3 PUFA deficiency. Thus, an optimal level of maternal omega-3 (n-3) PUFAs may protect the placenta's structural and functional integrity and allow fetal growth by controlling the aberrant placental epigenetic changes. This narrative review summarizes the recent advances and underpins the roles of maternal PUFAs on the structure and functions of the placenta and their relevance to fetal growth and brain development.

Research progress of placental vascular pathophysiological changes in pregnancy-induced hypertension and gestational diabetes mellitus

The placenta is a vital organ for fetal development, providing the fetus with nutrients, oxygen, and other important factors. Placenta is rich in blood vessels. Abnormal placental vascular function and blood circulation may lead to insufficient blood supply to the fetus in the uterus, leading to serious consequences such as pregnancy complications, fetal distress and even stillbirth. Pregnancy-induced hypertension (PIH) and gestational diabetes mellitus (GDM) are common complications of pregnancy. Recent studies report that pregnancy complications are often accompanied by changes in placental vascular structure and function. What are the physiological characteristics of human placental blood vessels? What are the pathological changes in the state of PIH and GDM? What are the relationships between these pathological changes and the occurrence of these pregnancy complications? Answers to these questions not only increase the understanding of placental vascular characteristics, but also provide important information for revealing the pathological mechanism of PIH and GDM. This article will summarize the research on the pathological changes of placental blood vessels in PIH and GDM, hoping to further unravel the physiological and pathological characteristics of placental blood vessels in the state of PIH and GDM, provide information for guiding clinical treatment for PIH and GDM.

Hypertensive diseases of pregnancy and risk of breast cancer in the Black Women's Health Study

PURPOSE

Compared to white women, Black women have increased risk of developing hypertensive diseases of pregnancy (HDOP) and have a higher incidence of aggressive breast cancer subtypes. Few studies of HDOP and breast cancer risk have included large numbers of Black women. This study examined the relation of HDOP to incidence of breast cancer overall and by estrogen receptor (ER) status in Black women.

METHODS

We followed 42,982 parous women in the Black Women's Health Study, a nationwide prospective study of Black women. Multivariable Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) to assess associations of self-reported HDOP, including preeclampsia and gestational hypertension, with breast cancer incidence overall and by ER subtype, adjusted for age and established breast cancer risk factors.

RESULTS

Over 20 years of follow-up, we identified 2376 incident breast cancer cases. History of HDOP (11.7%) was not associated with breast cancer risk overall (HR 0.98; 95% CI 0.87, 1.11). HRs for invasive ER+ and ER- breast cancer were 1.11 (95% CI 0.93, 1.34) and 0.81 (95% CI 0.61, 1.07), respectively.

CONCLUSIONS

HDOP was not associated with risk of overall breast cancer in Black women. A suggestive inverse association with ER- breast cancer may reflect an anti-tumorigenic hormone profile in HDOP, but those results require confirmation in other studies.

The Role of Syncytin in Placental Angiogenesis and Fetal Growth

Background: Syncytin, a retroviral envelope protein, is specifically expressed on trophoblast cells and mediates formation of the syncytiotrophoblast through fusogenic activity. Decreased expression of Syncytin was found in fetal growth restriction placentas. Results: By generating an inducible knockout of the syncytin-a gene in mice, we show a specific disruption of placental angiogenesis with abnormal formation of two syncytiotrophoblast layers. Consistent with the defects observed in vivo, conditioned medium collected from trophoblast cells, following Syncytin-1 knockdown, contains lower expression of vascular endothelial growth factor and placental growth factor, and higher levels of soluble fms-like protein kinase-1 in BeWo and HTR-8/SVneo cells which related with suppressed PI3K/Akt/mTOR pathway, and is reduced in ability to induce tube formation by HUVECs. Conclusion: Syncytin participates in angiogenesis during placental development was first identified both in vivo and in vitro. Here, we give a new sight on understanding syncytin and pathophysiology of placenta related disease such as fetal growth restriction.

Soluble CD146 is increased in preeclampsia and interacts with galectin-1 to regulate trophoblast migration through VEGFR2 receptor

OBJECTIVE

To explore the regulatory role of soluble CD146 (sCD146) and its interaction with galectin-1 (Gal1) in placenta-mediated complications of pregnancy.

DESIGN

Prospective pilot and experimental studies.

SETTING

University-affiliated hospital and academic research laboratory.

PATIENT(S)

One hundred fifteen women divided into three groups: 30 healthy, nonpregnant women, 50 women with normal pregnancies, and 35 with placenta-mediated pregnancy complications.

INTERVENTION(S)

Wound-healing experiments were conducted to study trophoblast migration.

MAIN OUTCOME MEASURE(S)

Quantification of sCD146 and Gal1 by enzyme-linked immunosorbent assay. Analysis of trophoblast migration by wound closure.

RESULT(S)

Concomitant detection of sCD146 and Gal1 showed lower sCD146 and higher Gal1 concentrations in women with normal pregnancies compared with nonpregnant women. In addition, follow-up of these women revealed a decrease in sCD146 associated with an increase in Gal1 throughout pregnancy. In contrast, in women with preeclampsia, we found significantly higher sCD146 concentrations compared with women with normal pregnancies and no modification of Gal1. We emphasize the opposing effects of sCD146 and Gal, since, unlike Gal1, sCD146 inhibits trophoblast migration. Moreover, the migratory effect of Gal1 was abrogated with the use of an anti-CD146 blocking antibody or the use of small interfering RNA to silence VEGFR2 expression. This suggests that trophoblast migration is mediated though the interaction of Gal1 with CD146, further activating the VEGFR2 signaling pathway. Significantly, sCD146 blocked the migratory effects of Gal1 on trophoblasts and inhibited its secretion, suggesting that sCD146 acts as a ligand trap.

CONCLUSION(S)

Soluble CD146 could be proposed as a biomarker in preeclampsia and a potential therapeutic target.

CLINICAL TRIAL REGISTRATION NUMBER

NCT 01736826.

Differential expression of Hsa-miR-517a/b in placental tissue may contribute to the pathogenesis of preeclampsia

Objective:

Preeclampsia (PE) is a pregnancy hypertensive disorder that affects both maternal and fetal health. Many studies have investigated possible mechanisms in the pathogenesis of PE although the role of the placenta is undeniable. Evaluation of placental-specific microRNAs may provide additional data about the pathogenic mechanism of PE. This study compared the expression levels of Hsa-miR-517a/b in placental tissues obtained from PE patients and healthy controls.

Material and Methods:

One hundred tissues were obtained from fetal and maternal sides of the placenta of PE patients and healthy controls. Expression analysis was performed using quantitative real-time polymerase chain reaction.

Results:

Hsa-miR-517a/b level was significantly decreased in PE compared to controls (expression ratio: 0.40; p=0.007). Down-regulation of Hsa-miR-517a/b was also detected in fetal-side placental samples when compared to maternal-side in PE (expression ratio: 0.33; p=0.04). Furthermore, decreased expression of Hsa-miR-517a/b was detected in fetal-side tissue from PE cases compared to fetal-side samples from healthy pregnancies (expression ratio: 0.36; p=0.03). In maternal-side placental samples the expression level did not differ between PE and healthy pregnancies (p=0.1).

Conclusion:

These results demonstrate a differential expression of Hsa-miR-517a/b within placentas in pregnancies affected by PE and between placentas from PE and healthy pregnancies. Further studies are required to investigate a possible role for Hsa-miR-517a/b in the pathogenesis of PE.

Long-Term Consequences of Placental Vascular Pathology on the Maternal and Offspring Cardiovascular Systems

Over the last thirty years, evidence has been accumulating that Hypertensive Disorders of Pregnancy (HDP) and, specifically, Preeclampsia (PE) produce not only long-term effects on the pregnant woman, but have also lasting consequences for the fetus. At the core of these consequences is the phenomenon known as defective deep placentation, being present in virtually every major obstetrical syndrome. The profound placental vascular lesions characteristic of this pathology can induce long-term adverse consequences for the pregnant woman's entire arterial system. In addition, placental growth restriction and function can, in turn, cause a decreased blood supply to the fetus, with long-lasting effects. Women with a history of HDP have an increased risk of Cardiovascular Diseases (CVD) compared with women with normal pregnancies. Specifically, these subjects are at a future higher risk of: Hypertension; Coronary artery disease; Heart failure; Peripheral vascular disease; Cerebrovascular accidents (Stroke); CVD-related mortality. Vascular pathology in pregnancy and CVD may share a common etiology and may have common risk factors, which are unmasked by the "stress" of pregnancy. It is also possible that the future occurrence of a CVD may be the consequence of endothelial dysfunction generated by pregnancy-induced hypertension that persists after delivery. Although biochemical and biophysical markers of PE abound, information on markers for a comparative evaluation in the various groups is still lacking. Long-term consequences for the fetus are an integral part of the theory of a fetal origin of a number of adult diseases, known as the Barker hypothesis. Indeed, intrauterine malnutrition and fetal growth restriction represent significant risk factors for the development of chronic hypertension, diabetes, stroke and death from coronary artery disease in adults. Other factors will also influence the development later in life of hypertension, coronary and myocardial disease; they include parental genetic disposition, epigenetic modifications, endothelial dysfunction, concurrent intrauterine exposures, and the lifestyle of the affected individual.

NK cells in hypoxic skin mediate a trade-off between wound healing and antibacterial defence

During skin injury, immune response and repair mechanisms have to be coordinated for rapid skin regeneration and the prevention of microbial infections. Natural Killer (NK) cells infiltrate hypoxic skin lesions and Hypoxia-inducible transcription factors (HIFs) mediate adaptation to low oxygen. We demonstrate that mice lacking the Hypoxia-inducible factor (HIF)-1α isoform in NK cells show impaired release of the cytokines Interferon (IFN)-γ and Granulocyte Macrophage - Colony Stimulating Factor (GM-CSF) as part of a blunted immune response. This accelerates skin angiogenesis and wound healing. Despite rapid wound closure, bactericidal activity and the ability to restrict systemic bacterial infection are impaired. Conversely, forced activation of the HIF pathway supports cytokine release and NK cell-mediated antibacterial defence including direct killing of bacteria by NK cells despite delayed wound closure. Our results identify, HIF-1α in NK cells as a nexus that balances antimicrobial defence versus global repair in the skin.

VEGF Maintains Maternal Vascular Space Homeostasis in the Mouse Placenta through Modulation of Trophoblast Giant Cell Functions

Vascular endothelial growth factor (VEGF) is an angiogenic growth factor that acts primarily on endothelial cells, but numerous studies suggest that VEGF also acts on non-endothelial cells, including trophoblast cells. Inhibition of VEGF signaling by excess production of the endogenous soluble VEGF receptor sFlt1 in trophoblast cells has been implicated in several pregnancy complications. Our previous studies and other reports have shown that VEGF directly regulates placental vascular development and functions and that excess VEGF production adversely affects placental vascular development. Trophoblast giant cells (TGCs) line the maternal side of the placental vasculature in mice and function like endothelial cells. In this study, we specifically examined the effect of excess VEGF signaling on TGC development associated with defective placental vascular development using two mouse models an endometrial VEGF overexpression model and a placenta-specific sFlt1 knockdown model. Placentas of endometrial VEGF-overexpressing dams at embryonic days (E) 11.5 and 14.5 showed dramatic enlargement of the venous maternal spaces in junctional zones. The size and number of the parietal TGCs that line these venous spaces in the placenta were also significantly increased. Although junctional zone venous blood spaces from control and VEGF-overexpressing dams were not markedly different in size at E17.5, the number and size of P-TGCs were both significantly increased in the placentas from VEGF-overexpressing dams. In sFlt1 knockdown placentas, however, there was a significant increase in the size of the sinusoidal TGC-lined, alkaline phosphatase-positive maternal blood spaces in the labyrinth. These results suggest that VEGF signaling plays an important role in maintaining the homeostasis of the maternal vascular space in the mouse placenta through modulation of TGC development and differentiation, similar to the effect of VEGF on endothelial cells in other vascular beds.

Reduction of serum-induced endothelial STAT3(Y705) activation is associated with preeclampsia

OBJECTIVES

Preeclampsia is associated with maternal morbidity and mortality during pregnancy, and also an increased cardiovascular disease (CVD) risk later in life. During preeclampsia, alterations in secreted placental factors leading to systemic maternal endothelial dysfunction are evident. However, little is known about the associated endothelial intracellular signaling. STAT3 is a latent cytoplasmic transcription factor involved in endothelial cell differentiation, survival, and angiogenesis. We aimed to test if preeclampsia and preeclampsia-related placental factors could alter serum-induced STAT3(Y705) activation in endothelial cells. Furthermore, if altered serum-induced endothelial STAT3 (Y705) activation is related to post-preeclamptic CVD risk.

STUDY DESIGN

HUVECs were used as a model of maternal endothelium. Experiments entailed addition of 20% human pregnancy serum as well as addition of recombinant PlGF, sFLT1 and VEGF-A_165a to the cells.

MAIN OUTCOME MEASURES

Levels of pSTAT3(Y705) related to STAT3 levels were evaluated by immunoblotting analysis.

RESULTS

Our results show that preeclamptic serum induces significantly lower STAT3(Y705) phosphorylation compared with uncomplicated pregnancy serum (P = 0.0089) in endothelial cells. Furthermore, STAT3(Y705) phosphorylation was not changed upon addition of PlGF, sFLT1, or VEGF-A_165a together with pregnancy sera compared with sera alone. Finally, sera from women with previous preeclampsia and current hypertension and carotid atherosclerotic plaques show significantly lower STAT3(Y705) phosphorylation capabilities compared with healthy women with previous uncomplicated pregnancies 8-18 years after deliveries (P = 0.029).

CONCLUSIONS

Reduction in serum-induced endothelial STAT3(Y705) activation may play an important role in the preeclampsia-associated endothelial dysfunction. Additionally, reduced endothelial STAT3(Y705) phosphorylation may contribute to increased post-preeclamptic CVD risk 8-18 years after delivery.

Role of Vitamin-D Receptor (VDR) single nucleotide polymorphisms in gestational hypertension development: A case-control study

Background

Recent literature data have highlighted the important role of hypovitaminosis D in pregnancy complications and prenatal/perinatal health. Vitamin D action takes place through vitamin D receptor (VDR) activation. Two single nucleotide polymorphisms of VDR gene, FokI and BsmI, have been reported to affect VDR molecular signaling and be associated with several disorders, including hypertension.

Methods

We carried out a case-control study aimed to assess vitamin D serum levels together with the distribution of VDR FokI and BsmI in a population of 116 pregnant women with gestational hypertension (GH) and 69 normotensive pregnant women (CTR).

Results

Hypovitaminosis D was largely prevalent both in GH (81%) and CTR (69%) pregnant women. Vitamin D insufficiency (10–30 ng/ml) had a similar frequency in both cohorts (GH 60% vs CTR 58%), while vitamin D deficiency (<10 ng/ml) was more frequent in GH cohort than in CTR one (21% vs 11%). Regression analysis showed that GH was significantly (p = 0.031) linked to vitamin D status. Vitamin D deficiency was associated with a threefold-increased risk of developing GH, while a normal vitamin D status was protective against this pregnancy disorder. The VDR FF/bB haplotype was the most frequent in GH cohort, and resulted to increase by two folds the risk for GH. Notably, hypovitaminosis D was found in 92% of FF/bB GH pregnant women, 27% of which had deficient vitamin D levels compared with 11% of their normotensive counterparts.

Conclusions

Despite being preliminary, these findings suggest that genotyping of pregnant women for VDR polymorphisms may be useful for a tailored vitamin D supplementation strategy.

Altered DNA methylation in human placenta after (suspected) preterm labor

Aim: The aim of this study was to determine if alterations in DNA methylation in the human placenta would support suspected preterm labor as a pathologic insult associated with diminished placental health. Methods: We evaluated placental DNA methylation at seven loci differentially methylated in placental pathologies using targeted bisulfite sequencing, in placentas associated with preterm labor (term birth after suspected preterm labor [n = 15] and preterm birth [n = 15]), and controls (n = 15). Results: DNA methylation levels at the NCAM1 and PLAGL1 loci in placentas associated with preterm labor did differ significantly (p < 0.05) from controls. Discussion: Specific alterations in methylation patterns indicative of an unfavourable placental environment are associated with preterm labor per se and not restricted to preterm birth.

Increased Angiogenesis and Lymphangiogenesis in the Placental Villi of Women with Chronic Venous Disease during Pregnancy

Pregnancy is a period in a woman’s life associated with an increased risk of developing lower extremity chronic venous disease (CVD). Pregnancy-associated CVD is associated with changes in placental villi. We investigated angiogenesis and lymphangiogenesis in the placental villi of women with CVD during pregnancy compared with healthy controls with no history of CVD (HC). An observational, analytical, and prospective cohort study was conducted on 114 women in their third trimester of pregnancy (32 weeks). Sixty-two participants were clinically diagnosed with CVD. In parallel, 52 controls with no history of CVD (HC) were studied. Gene and protein expression of CD31, podoplanin (D2-40), Flt-1, and placental growth factor (PIGF) was analysed by real-time polymerase chain reaction (RT-qPCR) and immunohistochemistry. CD31 and D2-40 gene expression was significantly greater in the placental villi of women with CVD, as were the numbers of vessels positive for CD31 and D2-40. Significantly higher gene and protein expression of Flt-1 and PIGF was observed in the placental villi of women with CVD. Histological analysis showed more placental villi with periodic acid of Schiff (PAS)-positive material in women with CVD. Our results show a connection between pregnancy-associated CVD and leading to higher proangiogenic and lymphangiogenic activity in placental villi.

Natural killer cells in the pathogenesis of preeclampsia: a double-edged sword

Objective: To investigate the relationship between natural killer (NK) cells, extravillous trophoblast cells (EVTs) and vessel remodeling in early human pregnancy, and the association between NK cells and preeclampsia (PE) in late human pregnancy.Methods: Human decidual tissues from women with normal pregnancies were collected and examined for the relationship of NK cells with uterine vessel remodeling using immunohistochemistry. Percentages of peripheral blood NK (pNK) and decidual NK (dNK) cells and the levels of intracellular interferon (IFN)-γ, perforin and granzyme B in normal pregnancies, late-onset and early-onset PE were analyzed using flow cytometry. Cytolytic functions of dNK cells from normal and PE pregnancies were examined. Effects of conditioned medium (CM) of dNK cells from normal and PE pregnancies on first trimester trophoblast invasion and migration were tested.Results: In early pregnancy samples (9-13 weeks of gestation), we noted moderate vessel remodeling with abundant perivascular NK cells but a limited number of surrounding EVTs. The numbers of both human pNK cells and dNK cells and intracellular interferon (IFN)-γ, perforin and granzyme B production were significantly higher in PE compared with normal pregnancies at the time of delivery for both early- and late-onset disease. dNK cells from PE pregnancies not only killed first trimester trophoblasts but also inhibited their invasion and migration when compared to normal controls.Conclusion: Our results suggest that NK cells, in conjunction with EVTs, may play an important role in controlling uterine SA remodeling at the early stages of vessel remodeling, but they contribute to the pathogenesis of PE in late pregnancy.

Ozone Exposure During Implantation Increases Serum Bioactivity in HTR-8/SVneo Trophoblasts

Implantation is a sensitive window in reproductive development during which disruptions may increase the risk of adverse pregnancy outcomes including intrauterine growth restriction. Ozone exposure during implantation in rats reduces fetal weight near the end of gestation, potentially though impaired trophoblast migration and invasion and altered implantation. The current study characterized changes in ventilation, pulmonary injury, and circulating factors including hormonal, inflammatory, and metabolic markers related to exposure to ozone (0.4-1.2 ppm) for 4-h on gestation days 5 and 6 (window of implantation) in Long-Evans dams. To determine the effects of this exposure on trophoblast function, placental-derived, first trimester, HTR-8/SVneo cells were exposed to serum from air- or ozone (0.8 ppm×4 h)-exposed dams and examined for impacts on metabolic capacity, wound-closure, and invasion. Peri-implantation exposure to ozone induced ventilatory dysfunction and lung vascular leakage in pregnant rats, with little effect on most of the circulating markers measured. However, ozone inhalation induced a significant reduction in several serum cytokines (interferon-γ, interleukin-6, and interleukin-13). Treatment of HTR-8/SVneo trophoblasts with serum from ozone-exposed dams for 16-h downregulated metabolic capacity, wound-closure, and invasion through a Matrigel membrane compared with both air-serum and fetal bovine serum-treated cells. Ozone-serum treated cells increased the release of a critical inhibitor of invasion and angiogenesis (soluble fms-like receptor 1; sFlt1) compared with air-serum treatment. Together, our data suggest that circulating factors in the serum of pregnant rats exposed to ozone during implantation receptivity can hinder critical processes of implantation (eg, invasion and migration) and impair trophoblast metabolic capacity.

Pre-eclampsia in a mother and programming of the child’s cardiovascular health

The authors present a review of the literature devoted to the problem of programming the formation of the cardiovascular system structure and function in children born from mothers with preeclampsia. These children are at high risk of developing cardiovascular diseases. Pre-eclampsia is caused by the endothelium dysfunction, deregulation of the immune and inflammatory factors during pregnancy. Experimental studies identify these factors as key epigenetic factors programming the condition of the cardiovascular system of the offspring. The modern concept of intrauterine programming, describing this phenomenon, focuses on three main areas of research: experimental models simulating the intrauterine environment with preeclampsia; research of the pathological phenotype formation under the influence of these factors; epigenetic studies of the influence of preeclampsia on the cardiovascular system functioning. The article discusses the perspectives of epigenetic programming prevention.

A Review of Angiogenic Imbalance in HIV-Infected Hypertensive Disorders of Pregnancy

PURPOSE OF REVIEW

This review provides a comprehensive insight into the angiogenic profile of hypertensive and normotensive pregnancies compromised by HIV infection. Furthermore, we evaluate the economic implementation of the sFlt-1/PlGF ratio and review the reports on therapeutic apheresis in limiting sFlt-1 production.

RECENT FINDINGS

In preeclampsia, an increased expression of sFlt-1 triggers angiogenic imbalance. Women of African ancestry have high levels of angiogenic factors than other racial groups. The sFlt-1/PlGF ratio shows promise in the early assessment of preeclampsia, while sFlt-1 apheresis restores angiogenic imbalance. Studies suggest antiretroviral therapy does not impact the angiogenic shift in preeclampsia development. The angiogenic profile in pregnant women of different races influences preeclampsia development. Despite the opposing immune response in HIV infection and preeclampsia, the HIV tat protein strongly mimics vascular endothelial growth factor (VEGF); hence, it is plausible to assume that HIV infection may ameliorate the angiogenic imbalance in preeclampsia.

CD133+/C-kit+Lin- endothelial progenitor cells in fetal circulation demonstrate impaired differentiation potency in severe preeclampsia

OBJECTIVES

Individuals delivered from preeclamptic pregnancies exhibit a long-term increased risk of developing cardiovascular and metabolic diseases, likely caused by aberrant fetal cell reprogramming incurred in utero. The present study investigated the functional impairment and epigenetic changes exhibited by endothelial progenitor cells derived from offspring born to preeclamptic pregnancies.

STUDY DESIGN

The capacity of CD133⁺/C-kit⁺/Lin^- (CKL^-) human umbilical cord blood endothelial progenitor cells (EPCs) derived from gestationally matched normal and preeclamptic (n = 10 each) pregnancies to differentiate to form outgrowth endothelial cells (OECs) was assessed by observing both their morphology, and the number and size of generated OECs colonies. Likewise, OECs angiogenic function was evaluated via migration, adhesion, and tube-formation assays. EPCs from preeclampsia were cultured in normal-, and preeclampsia-derived serum-conditioned media to assess the effects of environmental factors on EPC differentiation potency and OEC angiogenic function, and finally, EPCs H3K4, H3K9, and H3K27 trimethylation levels were assayed.

RESULTS

The preeclampsia-derived CKL^- EPCs exhibited decreased H3K4 and H3K9 trimethylation levels, significantly delayed differentiation times, and a significant reduction in both their number of generated OECs colonies, and exhibited reduced OECs migration, adhesion, and tube formation activities compared to those achieved by the normal-derived EPCs. Interestingly, the reduced differentiation potency of the preeclampsia-derived EPCs was not rescued via exposure to normal serum.

CONCLUSIONS

Exposure to preeclampsia significantly and irreversibly reduced CKL^- EPC differentiation potency and OEC angiogenic function, likely reflecting incurred irreversible epigenetic changes.

An intron variant in the FLT1 gene increases the risk of preeclampsia in Iranian women

Background: Preeclampsia is a hypertensive disorder that affects pregnancy, mother, and fetus. Pathogenesis of preeclampsia could be associated with the angiogenesis pathways. The vascular endothelial growth factor (VEGF) family is one of the important factors for normal pregnancy and angiogenesis. Genetic variations in the gene family members may play a role in the etiology of preeclampsia. We investigated the possible association between VEGFA gene rs3025039, and VEGFR1 (FLT1) gene rs722503 polymorphisms and preeclampsia in a sample of Iranian patients. Methods: Genotyping was performed in 395 women, including, 204 pre-eclamptic pregnant women and 191 healthy normotensive pregnant women by using the PCR-RFLP method. Results: The rs722503 polymorphism was associated with preeclampsia under the dominant model (P = 0.04, OR = 1.53, 95% CI: 1.03-2.27). No significant difference was observed for the rs3025039 alleles and genotypes in the studied groups. Conclusions: Based on our study, rs722503 polymorphism in the FLT1 gene may play an important role in susceptibility to preeclampsia.

AP39, a Modulator of Mitochondrial Bioenergetics, Reduces Antiangiogenic Response and Oxidative Stress in Hypoxia-Exposed Trophoblasts: Relevance for Preeclampsia Pathogenesis

Although the cause of preeclampsia, a pregnancy complication with significant maternal and neonatal morbidity, has not been fully characterized, placental ischemia attributable to impaired spiral artery remodeling and abnormal secretion of antiangiogenic factors are thought to be important in the pathogenesis of the disease. Placental ischemia could impair trophoblast mitochondrial function and energy production, leading to the release of reactive oxygen species (ROS). ROS have been shown to stabilize hypoxia-inducible factor (HIF)-1α, which, in turn, may induce transcription of antiangiogenic factors, soluble fms-like tyrosine kinase 1 (sFLT1), and soluble endoglin in trophoblasts. Herein, we tested whether the angiogenic imbalance and oxidative stress in the preeclamptic placenta may be prevented by improving mitochondrial function. First, to evaluate the cause-effect relationship between mitochondrial function and sFLT1 production, a human trophoblast primary cell culture model was established in which hypoxia induced mitochondrial ROS production and concurrent sFLT1 increase. Second, treatment with AP39, a novel mitochondria-targeted hydrogen sulfide donor, prevented ROS production, reduced HIF-1α protein levels, and diminished sFLT1 production. Finally, AP39, a modulator of mitochondrial bioenergetics enhanced cytochrome c oxidase activity, reversed oxidative stress and antiangiogenic response in hypoxic trophoblasts. These results suggest that placental hypoxia induces ROS production, HIF-1α stabilization, and sFLT1 up-regulation; these pathophysiological alterations can be attenuated by mitochondrial-targeted antioxidants.

High-fat diet reduces weight gain but increases other cardio-metabolic indices in offspring of normotensive and hypertensive rats

This study investigated the effect of post-natal consumption of high-fat diet (HFD) on cardio-metabolic indices in male offspring of hypertensive female rats. There were neither significant differences in body weight gain either in pups from normotensive or hypertensive dams that received normal diet during the post-weaning periods (except at 7th and 9th weeks), nor in both pup groups that received HFD. However, both pup groups that received HFD had reduced body weight gain when compared to their counterparts that received normal diet. Post-weaning administration of HFD to pups of hypertensive and normotensive dams significantly increased their blood glucose, pressure and lipid profiles when compared to those weaned to normal diet. It was concluded that male offspring consumption of HFD diet elicits cardio-metabolic disturbance that slightly depended of maternal cardiovascular status but majorly depended on post-weaning weight gain, while that elicited by maternal hypertension is not related to post-weaning weight gain.

Dexamethasone-induced Intra-Uterine Growth Restriction impacts NOSTRIN and its downstream effector genes in the rat mesometrial uterus

Intra-Uterine Growth Restriction (IUGR) is a major cause of fetal and neonatal mortality. Understanding the impact of IUGR on utero-placental gene expression is key to developing effective therapy. In this report we elucidated the impact of IUGR on NOSTRIN and its downstream effector gene expression in the utero-placental compartments. We showed here that induction of IUGR by maternal dexamethasone administration in rats led to up-regulation of NOSTRIN transcript and protein in the mesometrial triangle of the uterus (MG) and not in other utero-placental compartments as compared to control. This was associated with down-regulation of twelve genes and four cytokines that were known to be regulated by NOSTRIN and also required for maintenance of pregnancy. Interestingly, there was remarkable decrease in phosphorylation of RelA transcription factor in the MG during IUGR in line with the fact that the down regulated genes harbour RelA transcription activation domain in their promoters. Furthermore, HIF-1α level was reciprocal to NOSTRIN expression pattern in the mesometrial compartment during IUGR and also in CoCl₂ treated endothelial cells. Over-expression of HIF-1α led to a decrease in NOSTRIN levels suggesting inhibition of Nostrin transcription by HIF-1α. Our findings highlight the importance of NOSTRIN in uterine pathophysiology during IUGR.

The expression and activation of sex steroid receptors in the preeclamptic placenta

Estrogen and progesterone are the main pregnancy hormones produced by the placenta. It is well understood that estrogen stimulates angiogenesis in the uterus during the reproductive cycle. Although the estrogen and progesterone signaling pathways are assumed to be associated with placental vascularization and preeclampsia, expression of estrogen receptors (ESRs) and progesterone receptor (PGR) in the placenta have not been well studied. The present study examined the expression patterns of steroid hormone receptors in placentas. Human placenta samples were collected and divided into normal and preeclampsia groups. Results revealed that expression levels of ESR1 were reduced, whereas ESR2 and PGR were elevated in preeclamptic placentas. To generate an in vitro preeclampsia environment, human placenta‑derived BeWo cells were incubated under hypoxic conditions, or treated with catechol‑O‑methyl transferase inhibitor (COMT‑in) or L‑NG‑nitroarginine methyl ester (L‑NAME). Expression levels of ESR1, ESR2 and PGR in hypoxic cells demonstrated similar regulation as those in placentas from women with preeclampsia. Although COMT‑in and L‑NAME did not significantly regulate the expression levels of the receptors, COMT‑in translocated ESR2 and PGR from the nucleus to the cytoplasm, indicating that these receptors were inactivated. These results suggested that ESRs and PGR are associated with symptoms of preeclampsia in the placenta. The expression of ESR1 was reduced in preeclamptic placenta and hypoxic BeWo cells. In addition, the activation of ESR2 and PGR was blocked in placenta cells subjected to COMT‑in treatment. The reduced ESR1 expression and inactivation of ESR2 and PGR proteins may affect the physiological complications of preeclampsia in the placenta.

What is precise pathophysiology in development of hypertension in pregnancy? Precision medicine requires precise physiology and pathophysiology

It is widely accepted that placental ischemia is central in the evolution of hypertension in pregnancy. Many studies and reviews have targeted placental ischemia to explain mechanisms for initiating pregnancy hypertension. The placenta is rich in blood vessels, which are the basis for developing placental ischemia. However, is the physiology of placental vessels the same as that of nonplacental vessels? What is the pathophysiology of placental vessels in development of pregnancy hypertension? This review aims to provide a comprehensive summary of special features of placental vascular regulations and the pathophysiological changes linked to preeclamptic conditions. Interestingly, some popular theories or accepted concepts could be based on our limited knowledge and evidence regarding placental vascular physiology, pharmacology and pathophysiology. New views raised could offer interesting ideas for future investigation of mechanisms as well as targets for pregnancy hypertension.

Cord Blood Biomarkers of Placental Maternal Vascular Underperfusion Predict Bronchopulmonary Dysplasia-Associated Pulmonary Hypertension

OBJECTIVE

To assess whether cord blood biomarkers associated with placental maternal vascular underperfusion (MVU) are predictive of bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH).

STUDY DESIGN

Premature infants enrolled in a longitudinal cohort study were randomly sampled from 4 gestational age strata (n?=?190, range 23-36 weeks). Fifteen factors from a human angiogenesis panel were measured in cord blood using multiplex immunoassay. Multivariate linear regression was used to compare biomarker levels according to placental histologic MVU, taking into account acute/chronic inflammation and fetal vascular pathology. Biomarkers associated with MVU were further evaluated in the subgroup of extremely low gestational age infants (gestational age ? 28 weeks; n?=?48), and measured by enzyme-linked immunoassay in an additional 39 infants to determine associations with BPD (defined using the National Institutes of Health workshop criteria) and PH (identified by echocardiogram at 36 weeks of gestation).

RESULTS

Cord blood placental growth factor (PIGF), granulocyte-colony stimulating factor (G-CSF), and vascular endothelial growth factor-A were decreased with MVU (P?<?.003), and decreased with BPD-PH (P?<?.05). The findings were validated for PIGF and G-CSF in 39 additional extremely low gestational age infants. In the combined group (n?=?87), PIGF was decreased in infants with BPD-PH (n?=?21) versus controls without PH (median 3 pg/mL [IQR 2-7] vs median 15 pg/mL [IQR 6-30], respectively; P?<?.001). G-CSF was similarly decreased with BPD-PH (median, 55 pg/mL [IQR 38-85] vs median 243 pg/mL [IQR 48-1593], respectively; P?=?.001). Receiver operator curve analysis revealed that decreased PIGF and G-CSF were predictive of BPD-PH (area under the curve 0.83 and 0.76, respectively).

CONCLUSIONS

Cord blood angiogenic factors that are decreased with placental MVU may serve as predictors of BPD-PH.

Expression of placental growth factor mRNA in preeclampsia

BACKGROUND

Preeclampsia (PE) is a serious complication of pregnancy with hallmarks of incomplete placentation, placental ischemia and endothelial dysfunction. Imbalance between vascular endothelial growth factor (VEGF), placenta growth factor (PlGF) and their receptors play important role in pathophysiology of PE.

OBJECTIVE

This study was aimed to asses PlGF mRNA expression in placenta of women affected with PE.

MATERIAL AND METHODS

In this cross-sectional study, expression of PlGF mRNA was evaluated in 26 mild PE cases, 15 severe preeclamptic women and 20 normotensive controls. Patients were sub-classified as early onset PE (9) and late onset (32). After RNA extraction, PlGF expression was quantified with qRT-PCR.

RESULTS

The results of PlGF mRNA expression between mild-severe, and early-late onset PE patients showed no statistically significant difference compared with the control group (p=0.661, p=0.205 respectively).

CONCLUSION

Despite we found no distinct differential expression of PlGF mRNA in placental tissue of PE patients compared with control women, but according to decreased level of this angiogenic factor in PE even before clinical onset of the disease, determining molecular mechanisms related to reduced secretion of PlGF into the maternal circulation may be useful for future therapeutics.

Effect of THP-1 Cells on the Formation of Vascular Tubes by Endothelial EA.hy926 Cells in the Presence of Placenta Secretory Products

We studied the effect of THP-1 cells on the formation of vessel-like structures by endothelial cells in the presence of placenta-conditioned media. Addition of THP-1 cells to endothelial cells cultured in the presence of media conditioned by first-trimester placentas led to an increase in the length of cell tubes and reduced their number in comparison with endothelial cell monoculture. In the presence of media conditioned by third-trimester placentas, THP-1 cells did not affect the length and number of cell tubes formed by endothelial cells. When evaluating the formation of vessel-like structures by endothelial cells in co-culture, marked decrease in the length of cell tubes in the presence of media conditioned by first-trimester placentas vs. third-trimester placentas was noted. No differences in the length and number of cell tubes formed by endothelial cells co-cultured with THP-1 cells in the presence of placental factors from women with preeclampsia and uncomplicated pregnancy were found. These findings can reflect the peculiarities of the influence of macrophages on the formation of blood vessels by endothelial cells in the placenta.

Bone Marrow-Derived Endothelial Progenitor Cells Reduce Recurrent Miscarriage in Gestation

Bone marrow-derived endothelial progenitor cells (EPCs) have been shown to contribute to not only angiogenesis in ischemic tissue but also neovascularization in uterine endometrium formation. Reduced neovascularization and elevation of serum soluble Flt1, a functional blockage of VEGF, in the development of placenta is thought to be one of the major causes of repeated miscarriages in gestation. We then examined whether transfusion of VEGF-expressing extrinsic EPCs prevented frequent miscarriage via its promotional effect on neovascularization with a VEGFeNOS signaling pathway in a mouse miscarriage model. The results showed that systemic EPC transfusion significantly reduced the rate of miscarriage, and EPCs were frequently observed in the miscarriage placenta. In contrast, only a few EPCs were detected in the placenta of normal gestation. The vascular pattern was irregular, and vessel size was small in the miscarriage placenta compared with that of normal gestation. The placental vascular pattern in miscarriage tended to be normalized with increased vessel size up to a similar level as normal gestation by EPC recruitment. For the mechanistic insight, since soluble Flt1 inhibits EPC functions, it was suggested that the increased soluble Flt1 could suppress the recruited EPC functional activity in the miscarriage placenta. In vitro experiments by soluble Flt1 treatment in cultured EPCs suggested that the vascular abnormality could be partly due to the inhibition of eNOS expression by the increased amounts of soluble Flt1. These findings from animal experiments indicated that autologous EPC therapy may be a novel therapy to prevent miscarriage in high-risk pregnancies, such as preeclampsia.

A Dormant Microbial Component in the Development of Preeclampsia

Preeclampsia (PE) is a complex, multisystem disorder that remains a leading cause of morbidity and mortality in pregnancy. Four main classes of dysregulation accompany PE and are widely considered to contribute to its severity. These are abnormal trophoblast invasion of the placenta, anti-angiogenic responses, oxidative stress, and inflammation. What is lacking, however, is an explanation of how these themselves are caused. We here develop the unifying idea, and the considerable evidence for it, that the originating cause of PE (and of the four classes of dysregulation) is, in fact, microbial infection, that most such microbes are dormant and hence resist detection by conventional (replication-dependent) microbiology, and that by occasional resuscitation and growth it is they that are responsible for all the observable sequelae, including the continuing, chronic inflammation. In particular, bacterial products such as lipopolysaccharide (LPS), also known as endotoxin, are well known as highly inflammagenic and stimulate an innate (and possibly trained) immune response that exacerbates the inflammation further. The known need of microbes for free iron can explain the iron dysregulation that accompanies PE. We describe the main routes of infection (gut, oral, and urinary tract infection) and the regularly observed presence of microbes in placental and other tissues in PE. Every known proteomic biomarker of "preeclampsia" that we assessed has, in fact, also been shown to be raised in response to infection. An infectious component to PE fulfills the Bradford Hill criteria for ascribing a disease to an environmental cause and suggests a number of treatments, some of which have, in fact, been shown to be successful. PE was classically referred to as endotoxemia or toxemia of pregnancy, and it is ironic that it seems that LPS and other microbial endotoxins really are involved. Overall, the recognition of an infectious component in the etiology of PE mirrors that for ulcers and other diseases that were previously considered to lack one.

Correlation between cell-free mRNA expressions and PLGF protein level in severe preeclampsia

BACKGROUND

Preeclampsia is a major cause of morbidity and mortality, both maternal and perinatal. The etiology and pathophysiology of preeclampsia remain unknown. Research shows the implantation of the placenta in preeclampsia occurs due to incomplete angiogenic imbalance as one of the preeclampsia pathogenesis. PlGF is angiogenic protein which is synthesized in placenta by mRNA PlGF. When damage occurs, mRNA will be released from cell and form cell-free mRNA. This study aims to analyze the differences between the PlGF mRNA expression in severe preeclampsia and normal pregnancy as well as to measure the relationship between cell-free mRNA and levels of PlGF with the incidence of severe preeclampsia.

METHODS

The method used in this study is an observational analytic study with cross-sectional design. Blood samples were obtained from patients with preeclampsia and normal pregnancies as the controlling factors in accordance with inclusion and exclusion criterias. Examination of the PlGF level was measured by ELISA method and mRNA PIGF expression was measured by RT-PCR. Physical and laboratory examinations of patients were recorded and collected as data. Calculations were done by statistical analysis.

RESULTS

Mean of the cell-free mRNA PlGF expression level in severe preeclampsia is 2.2983 ng/mL within the scale of 1.96-2.83 ng/mL and deviation standard of 0.1897. Using Pearson Analysis Test, the result shows that there is a positive correlation between cell-free mRNA expression and PlGF protein level in severe preeclampsia, with r = 0.640 dan p < 0.004.

CONCLUSION

There is no difference between expression of cell-free mRNA PlGF in severe preeclampsia serum and normal pregnancy. There is a significant correlation between expression of cell-free mRNA and PlGF protein level in severe preeclampsia.

Is the imbalance between pro-angiogenic and anti-angiogenic factors associated with preeclampsia?

BACKGROUND

Preeclampsia (PE) is a multisystem disease characterized by the development of hypertension and proteinuria. Although PE etiology is not fully known, the placenta seems to play a central role in the development of disease. The inadequate placentation process results in a change in angiogenic factors levels, such as vascular endothelial growth factor (VEGF), placental growth factor (PlGF), soluble form of endoglin (s-Eng) and soluble form of vascular endothelial growth factor receptor type 1 (sFlt-1).

OBJECTIVE

The aim of this review was to clarify if the imbalance between pro-angiogenic and anti-angiogenic factors is associated with PE.

CONCLUSION

It is known that inadequate placentation process is the primary mechanism suggested for PE occurrence and angiogenic factors are involved in this process. The state-of-the-art suggests that progress in grasp the imbalance of pro-angiogenic and anti-angiogenic factors is essential for the improvement of knowledge about PE. The development of prospective, longitudinal studies with serial determinations of these factors throughout pregnancy is needed to better assess the relevance of these markers for understanding the etiology, prevention, diagnosis, prognosis and treatment of this challenging disease.

The imbalance in expression of angiogenic and anti-angiogenic factors as candidate predictive biomarker in preeclampsia

Preeclampsia is an important pregnancy disorder with serious maternal and fetal complications which its etiology has not been completely understood yet. Early diagnosis and management of disease could reduce its potential side effects. The vascular endothelial growth factor (VEGF) family including VEGF-A is the most potent endothelial growth factor which induces angiogenesis and endothelial cell proliferation and has basic role in vasculogenesis. VEGF and its tyrosine kinase receptors (Flt1 and KDR) are major factors for fetal and placental angiogenic development. Finding mechanisms involved in expression of angiogenic factors may lead to new prognostic and therapeutic points in management of preeclampsia. Recent researches, has shown capability of some anti-angiogenic factors as potential candidate to be used as early predictors for preeclampsia. Soluble fms-like tyrosin kinase-1 (sFlt1) is a truncated splice variant of the membrane-bound VEGF receptor Flt1, that is produced by the placenta and it can bind to angiogenic growth factors and neutraliz, their effects. It is also observed that the ratio of sFlt1 to placental growth factor is valuable as prognostic marker. In this review, VEGF family member's role in angiogenesis is evaluated as biomarkers to be used for prediction of preeclampsia.

Preeclampsia, prematurity and cardiovascular health in adult life

Investigations into how perinatal growth and intrauterine environment may 'programme' risk of later cardiovascular disease have been ongoing for over two decades. One of the more recent outcomes of these studies is the observation that certain pregnancy-related conditions, such as preterm birth, have an unusually large impact on the long-term cardiovascular health of the offspring. In the present paper, we review the current literature of how preterm birth affects the long-term cardiovascular structure and function of the offspring, considering three major areas of investigation: firstly, outlining the long-term cardiovascular phenotypic changes in preterm-born individuals; secondly, investigating factors related to preterm birth that may be modifying cardiovascular phenotype, such as preeclampsia, perinatal interventions, and physiological disturbances; and thirdly, the expected clinical relevance of these cardiovascular changes. This review discusses the importance of continued research focused on the mechanistic understanding of these cardiovascular alterations in order to develop specific primary prevention strategies.

Influence of maternal pre-eclampsia on VEGF/PlGF heterodimer levels in preterm infants

OBJECTIVE

To measure VEGF/PlGF heterodimer levels in preterm infants born to mothers with preeclampsia.

METHODS

Neonates with birth weight <2000 g and gestational age ≤34 weeks were divided into two groups: born to mothers with Preeclampsia (PE) and controls. Neonates transferred from outside after the 72nd hour of life, death before blood collection, major congenital malformations or inborn errors of metabolism, and mothers with multiple pregnancies, STORCH complex infections, HIV or autoimmune conditions were excluded. Blood was collected within 72 h of birth and again at 28 days. VEGF/PlGF heterodimer levels were measured by ELISA.

RESULTS

We included 73 neonates (24 born to mothers with PE and 49 without PE). Mean gestational age was 30.32 ± 2.88 weeks and mean birth weight was 1288.62 ± 462.22 g. Median VEGF/PlGF levels were significantly higher in infants born to mothers with PE. VEGF/PlGF levels were inversely proportional to birth weight. There were no between-group differences in blood samples collected at age 28 days.

CONCLUSION

Higher VEGF/PlGF levels were higher in neonates exposed to PE, and there was a significant negative correlation between birth weight and VEGF/PlGF levels. Further studies to elucidate the role of this substance in the fetal and neonatal period are needed.

Concentrations of endothelial nitric oxide synthase, angiotensin-converting enzyme, vascular endothelial growth factor and placental growth factor in maternal blood and maternal metabolic status in pregnancy complicated by hypertensive disorders

Hypertensive disorders of pregnancy (HDPs) are associated with altered maternal metabolism, impaired perinatal outcome and increased risk for remote maternal complications. The aim of our study was to analyse associations between circulating levels of angiogenic factors and markers of oxidative stress and metabolic status in women with HDP. Forty-six women in singleton pregnancies complicated by HDP and 30 healthy controls were enrolled in a prospective observational study. Serum concentrations of endothelial nitric oxide synthase (eNOS), angiotensin-converting enzyme, vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) were measured in the third trimester and correlated with maternal anthropometrics and metabolic status. We found significantly lower eNOS levels in patients with severe hypertension vs controls, a strong association between eNOS and PlGF in the study group, a significant association between maternal prepregnancy body mass index (BMI) and VEGF levels and an inverse correlation between VEGF and PlGF. Maternal prepregnancy BMI was the only independent predictor for VEGF concentrations. We noted reduced levels of PlGF and eNOS and increased VEGF levels in women with severe hypertension/preeclampsia. First, different forms of HDP are associated with different alteration patterns in concentrations of angiogenic factors and markers of oxidative stress. Second, maternal prepregnancy BMI, but not body weight, is a significant predictor for VEGF levels in late pregnancy.

FSH receptor (FSHR) expression in human extragonadal reproductive tissues and the developing placenta, and the impact of its deletion on pregnancy in mice

Expression and function of the follicle-stimulating hormone receptor (FSHR) in females were long thought to be limited to the ovary. Here, however, we identify extragonadal FSHR in both the human female reproductive tract and the placenta, and test its physiological relevance in mice. We show that in nonpregnant women FSHR is present on: endothelial cells of blood vessels in the endometrium, myometrium, and cervix; endometrial glands of the proliferative and secretory endometrium; cervical glands and the cervical stroma; and (at low levels) stromal cells and muscle fibers of the myometrium. In pregnant women, placental FSHR was detected as early as 8-10 wk of gestation and continued through term. It was expressed on: endothelial cells in fetal portions of the placenta and the umbilical cord; epithelial cells of the amnion; decidualized cells surrounding the maternal arteries in the maternal decidua; and the stromal cells and muscle fibers of the myometrium, with particularly strong expression at term. These findings suggest that FSHR expression is upregulated during decidualization and upregulated in myometrium as a function of pregnancy. The presence of FSHR in the placental vasculature suggests a role in placental angiogenesis. Analysis of genetically modified mice in which Fshr is lacking in fetal portions of the placenta revealed adverse effects on fetoplacental development. Our data further demonstrate FSHB and CGA mRNAs in placenta and uterus, consistent with potential local sources of FSH. Collectively, our data suggest heretofore unappreciated roles of extragonadal FSHR in female reproductive physiology.

Feto-maternal correlation of PTX3, sFlt-1 and PlGF in physiological and pre-eclamptic pregnancies

OBJECTIVE

PTX3, sFlt-1 and PlGF levels in maternal blood are altered in some obstetric diseases, such as preeclampsia (PE). Nonetheless, only few data on their expression in the fetal compartment have been reported so far.

STUDY DESIGN

An observational study was performed by prospectively collecting maternal and fetal serum samples in 51 singleton pregnancies divided into two groups: 22 PE women and 29 healthy controls. The relationships between maternal and fetal marker serum levels were evaluated by Spearman correlation.

RESULTS

A feto-maternal correlation was neither identified for PTX3 in either PE or control groups (1.1 versus 3.8 ng/ml, p = 0.17 and 0.9 versus 1.3 ng/ml, p = 0.30, respectively), nor for sFlt-1 and PlGF in healthy pregnancies (158.2 versus 3326.0 pg/ml, p = 0.28 and 11.0 versus 230.9 pg/ml, p = 0.51). In contrast, PE patients showed a significant positive feto-maternal correlation for both sFlt-1 and PlGF (324.1 versus 10 825.0 pg/ml and 7.8 versus 31.6 pg/ml, respectively, p = 0.02 for both markers).

CONCLUSION

According to our results, an independent fetal production of the analyzed soluble angiogenic markers can be hypothesized in pregnancies complicated by PE.

Expression of the sFLT1 gene in cord blood cells is associated to maternal arsenic exposure and decreased birth weight

There is increasing epidemiologic evidence that arsenic exposure in utero is associated with adverse pregnancy outcomes and may contribute to long-term health effects. These effects may occur at low environmental exposures but the underlying molecular mechanism is not clear. We collected cord blood samples of 183 newborns to identify associations between arsenic levels and birth anthropometric parameters in an area with very low arsenic exposure. Our core research aim was to screen for transcriptional marks that mechanistically explain these associations. Multiple regression analyses showed that birth weight decreased with 47 g (95% CI: 16–78 g) for an interquartile range increase of 0.99 μg/L arsenic. The model was adjusted for child’s sex, maternal smoking during pregnancy, gestational age, and parity. Higher arsenic concentrations and reduced birth weight were positively associated with changes in expression of the sFLT1 (soluble fms-like tyrosine kinase-1) gene in cord blood cells in girls. The protein product of sFLT1 is a scavenger of vascular endothelial growth factor (VEGF) in the extracellular environment and plays a key role in the inhibition of placental angiogenesis. In terms of fetal development, inhibition of placental angiogenesis leads to impaired nutrition and hence to growth retardation. Various genes related to DNA methylation and oxidative stress showed also changed expression in relation to arsenic exposure but were not related to birth outcome parameters. In conclusion, this study suggests that increased expression of sFLT1 is an intermediate marker that points to placental angiogenesis as a pathway linking prenatal arsenic exposure to reduced birth weight.

Increased angiogenic factor secretion by decidual natural killer cells from pregnancies with high uterine artery resistance alters trophoblast function

STUDY QUESTION

Are the concentrations of factors secreted by decidual natural killer (dNK) cells from pregnancies at high risk of poor spiral artery remodelling different to those secreted from pregnancies at low risk?

SUMMARY ANSWER

Expression levels of PLGF, sIL-2R, endostatin and angiogenin were significantly increased by dNK cells from high-risk pregnancies, and angiogenin and endostatin were found to alter trophoblast function.

WHAT IS KNOWN ALREADY

During early pregnancy, maternal uterine spiral arteries are remodelled from small diameter, low-flow, high-resistance vessels into larger diameter, higher flow vessels, with low-resistance. This change is essential for the developing fetus to obtain sufficient oxygen and nutrients. dNK cells have been implicated in this process.

STUDY DESIGN, SIZE, DURATION

dNK cells were isolated from first trimester terminations of pregnancies (obtained with local ethical approval) screened for normal- or high-resistance index, indicative of cases least (<1%) and most (>21%) likely to have developed pre-eclampsia had the pregnancy not been terminated (n = 18 each group). Secreted factors and the effects of these on the trophoblast cell line, SGHPL-4, were assessed in vitro.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A multiplex assay was used to assess dNK cell-secreted factors. SGHPL-4 cell functions were assessed using time-lapse microscopy, 3D invasion assays, endothelial-like tube formation ability and western blot analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

The expression levels of PLGF (P < 0.01), sIL-2R (P < 0.01), endostatin (P < 0.05) and angiogenin (P < 0.05) were significantly increased by dNK cells from high-risk pregnancies. Endostatin significantly decreased SGHPL-4 invasion (P < 0.05), SGHPL-4 tube formation (P < 0.05) and SGHPL-4 Akt^ser473 phosphorylation (P < 0.05). Angiogenin significantly decreased SGHPL-4 invasion (P < 0.05), but increased SGHPL-4 tube formation (P < 0.01) and decreased SGHPL-4 Akt^ser473 phosphorylation (P < 0.05).

LIMITATIONS, REASONS FOR CAUTION

The culture of dNK cells and protein concentrations in vitro may not fully represent the in vivo situation. Although SGHPL-4 cells are extravillous trophoblast derived, further studies would be needed to confirm the roles of angiogenin and endostatin in vivo.

WIDER IMPLICATIONS OF THE FINDINGS

The altered expression of secreted factors of dNK cells may contribute to pregnancy disorders associated with poor spiral artery remodelling.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the Wellcome Trust (project reference 091550). R.F. was a recipient of a PhD studentship from the Division of Biomedical Sciences, St. George's, University of London. The authors have no conflict of interests.

Evidence of an imbalance of angiogenic/antiangiogenic factors in massive perivillous fibrin deposition (maternal floor infarction): a placental lesion associated with recurrent miscarriage and fetal death

OBJECTIVE

Massive perivillous fibrin deposition (MPFD) is associated with serious complications of pregnancy including recurrent spontaneous abortion, fetal growth restriction, and fetal demise. The aim of this study was to determine whether maternal plasma concentrations of angiogenic/antiangiogenic factors in MPFD differ from those of uncomplicated pregnancies.

STUDY DESIGN

This retrospective longitudinal case-control study included MPFD cases (n = 10) and control patients (n = 175) with uncomplicated pregnancies who were enrolled in a longitudinal study and delivered at term. Serial plasma concentrations of placental growth factor (PlGF), soluble endoglin (sEng), and soluble vascular endothelial growth factor receptor (sVEGFR)-1 and -2 were determined by an enzyme-linked immunosorbent assay (cases, n = 28 samples; controls, n = 723 samples). Individual analyte concentrations were averaged across gestational age at specimen collection intervals. Linear mixed models were used to test for differences in log-transformed mean analyte concentrations both overall and as a function of time.

RESULTS

The following results were found: (1) patients with MPFD had a lower mean plasma PlGF concentration (P = .03) and higher mean plasma concentrations of sVEGFR-1 and sEng (both P < .01) than controls, adjusted for potential confounders; (2) the mean plasma concentration of PlGF differed further among cases and controls as a function of gestational age interval (P < .0001); however, mean sVEGFR-1 and sEng group differences as a function of gestational age interval approached but did not reach significance (P = .09 and P = .11, respectively); (3) patients with MPFD had lower mean plasma concentrations of PlGF/sVEGFR-1 (P < .0001) and PlGF/sEng (P < .001): both of these relationships differed further as a function of gestational age interval (both P < .0001); and (4) differences in mean sVEGFR-1, sEng, and the ratios of PlGF to sVEGFR-1 and PlGF to sEng were observed before 20 weeks of gestation.

CONCLUSION

An imbalance of angiogenic/antiangiogenic factors is present in patients with MPFD prior to the diagnosis. We propose that these changes participate in the mechanisms responsible for adverse pregnancy outcomes in patients with MPFD.

An Association between Bevacizumab and Recurrent Posterior Reversible Encephalopathy Syndrome in a Patient Presenting with Deep Vein Thrombosis: A Case Report and Review of the Literature

Background. The posterior reversible encephalopathy syndrome (PRES) is a syndrome characterized by hypertension, headache, seizures, and visual disturbances. Causes of PRES include preeclampsia/eclampsia, hypertension, and recently bevacizumab, a monoclonal antibody vascular endothelial growth factor (VEGF) inhibitor. There is no information to date about PRES recurrence in patients taking bevacizumab or descriptions of deep vein thrombosis (DVT) in the setting of PRES. We reviewed data on a patient receiving bevacizumab who presented with a DVT and PRES and later developed recurrent PRES. Case. A 72-year-old man with metastatic pulmonary adenocarcinoma received maintenance bevacizumab following six cycles of carboplatin and paclitaxel. Following his eighth dose of bevacizumab, he developed a DVT as well as PRES. He made a rapid recovery and was discharged from the hospital but went on to develop PRES recurrence nine days following his original episode. Conclusion. Several mechanisms exist whereby exposure to bevacizumab could be related to the development of both DVT and PRES by inducing global endothelial dysfunction. Recurrent PRES may result from bevacizumab's prolonged half-life (11-50 days) and suboptimal blood pressure control. In the setting of bevacizumab, PRES surveillance may play a similar role in preeclampsia screening as both diseases share similar antiangiogenic signaling pathways.