Anti-angiogenic Factors sFlt-1 Research Articles

CCN1-Mediated Signaling in Placental Villous Tissues after SARS-CoV-2 Infection in Term Pregnant Women: Implications for Dysregulated Angiogenesis.

The global spread of SARS-CoV-2 has increased infections among pregnant women. This study aimed to explore placental pathology alterations and angiogenic factor levels in term pregnant women after SARS-CoV-2 infection in a retrospective single-center study. Additionally, we investigated the role and underlying mechanism of the vascular inflammation-promoting, cysteine-rich protein 61 (CYR61/CCN1) in this context. All analyses were performed in term pregnant women infected with or without SARS-CoV-2. The sFlt-1, PlGF, and sEng serum levels were quantified using ELISA. Placental protein expressions were examined by immunoblot and immunostaining. Additionally, the effect of CCN1 protein on SGHPL-5 trophoblast cells was examined. We found that SARS-CoV-2 activated the inflammatory response in pregnant women, leading to pronounced vascular alterations in placental villous tissues. Elevated serum anti-angiogenic factors (sFlt-1, sEng) upon SARS-CoV-2 infection may directly contribute to these pathological changes. Upregulated CCN1 and pNF-κB in placental villous tissues of infected patients are identified as crucial factors in placental alterations. As a conclusion, CCN1 was significantly elevated in the placentas of term pregnant women infected with SARS-CoV-2. By activating a cascade of inflammatory responses, CCN1 induced the production of the anti-angiogenic factors sFlt-1 and sEng, which may lead to abnormal placental vascular architecture.

Effects of a combination of cannabidiol and delta-9-tetrahydrocannabinol on key biological functions of HTR-8/SVneo extravillous trophoblast cells

In recent years, cannabis use has increased among pregnant women. In addition, the phytocannabinoids cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) alone or in combination are being used for therapeutical applications. THC and CBD are able to cross the placenta and a lot remains unknown concerning their impact on angiogenesis and extravillous trophoblasts’ (EVTs) migration and invasion, which are essential processes for placentation. Thus, in this study, the HTR-8/SVneo cell line was employed to evaluate the effects of CBD, THC and of their combination (1:1, 2 µM). Cannabinoids affected epithelial-mesenchymal transition, as showed by increased expression of the epithelial protein marker E-cadherin for CBD and CBD plus THC treatments, and decrease of mesenchymal intermediate filament vimentin for all treatments. The gene expression of the metalloproteinases MMP2 and MMP9, and of their inhibitors TIMP1 and TIMP2 was increased, except the latter for THC treatment. Moreover, CBD reduced cell migration and invasion, an effect that was enhanced by its combination with THC. CBD with or without THC also upregulated the gene expression of PGF, while the anti-angiogenic factor sFLT1 was increased for all treatments. VEGFA and FLT1 were not affected. Alone or combined CBD and THC also decreased tube segments’ length. Additionally, ERK1/2 and STAT3 phosphorylation was increased in the CBD and CBD plus THC-treated cells, while THC only activated STAT3. AKT activation was only affected by CBD. This work demonstrates that the exposure to cannabinoid-based products containing CBD and/or THC, may interfere with key processes of EVTs differentiation. Therefore, crucial phases of placental development can be affected, compromising pregnancy success.

Sequential disruptions to inflammatory and angiogenic pathways and risk of spontaneous preterm birth in Malawian women

Preterm birth is a leading cause of death in children under five years of age. We hypothesized that sequential disruptions to inflammatory and angiogenic pathways during pregnancy increase the risk of placental insufficiency and spontaneous preterm labor and delivery. We conducted a secondary analysis of inflammatory and angiogenic analytes measured in plasma samples collected across pregnancy from 1462 Malawian women. Women with concentrations of the inflammatory markers sTNFR2, CHI3L1, and IL18BP in the highest quartile before 24weeks gestation and women with anti-angiogenic factors sEndoglin and sFlt-1/PlGF ratio in the highest quartile at 28-33weeks gestation had an increased relative risk of preterm birth. Mediation analysis further supported a potential causal link between early inflammation, subsequent angiogenic dysregulation detrimental to placental vascular development, and earlier gestational age at delivery. Interventions designed to reduce the burden of preterm birth may need to be implemented before 24weeks of gestation.

The protective effect of magnesium sulfate on placental inflammation via suppressing the NF-κB pathway in a preeclampsia-like rat model.

Abnormal placental inflammation has a role in the pathophysiology of preeclampsia. Magnesium sulfate (MgSO4) has anti-inflammatory properties and is a fetal neuroprotective agent. MgSO4 is often used to treat severe preeclampsia; however, the specificmechanisms of action underlyingthistherapeutic effect remain unclear. The objective of this study was to investigate the effects of MgSO4 (270mg/kg) on placental inflammation in a rat model of lipopolysaccharide (LPS; 1.0µg/kg)-induced preeclampsia. Compared to normal pregnant rats, LPS-treated pregnant rats had higher blood pressure, proteinuria, and expression of the anti-angiogenic factor sFlt-1 and the pro-inflammatory factors interleukin-1β (IL-1β) and IL-12 in placental tissue. LPS-treated pregnant rats had placental insufficiency, poor fetal outcomes, and significantly decreased expression of the anti-inflammatory factors apolipoprotein E (APOE) and IL-10 in placental tissue. MgSO4 treatment had favorable effects on maternal and fetal outcomes. MgSO4 treatment improved placental function by repressing an exaggerated inflammatory response in the placenta and promoting angiogenesis via the NF-κB pathway. These findings suggest MgSO4 has a potential role in the prevention of preeclampsia and in the treatment of mild and moderate preeclampsia.

Angiogenic imbalance as a starting point for the development of placental dysfunction and pregnancy complications in patients with pathology of the fetal environment

In recent years, scientific views on perinatal protection of fetus have shifted to earlier periods of pregnancy – to the I trimester, because from this stage the formation of the fetoplacental complex and laying of organs and tissues take place, which in most cases determines the further course of pregnancy. The objective: to clarify the role of the imbalance of angiogenic growth factors as one of the pathogenetic mechanisms in the development of placental dysfunction, and to conduct a postnatal macromorphometric study of placenta and umbilical cord in women with pathology of the fetal environment. Materials and methods. The object of the study were 80 pregnant women (the main group) with a singleton pregnancy, selected from the cohort of patients from the risk group for the development of preeclampsia and miscarriage. Among them, at 30–32 weeks of gestation oligohydramnios was diagnosed in 40 patients (the first group) and polyhydramnios – in 40 women (the second group). The control group included 30 somatically healthy pregnant women with a normal volume of amniotic fluid and a physiological course of pregnancy.The concentrations of placental growth factor (PlGF), vascular endothelial growth factor-1 (VEGF-1), and an anti-angiogenic marker of neovasculogenesis, soluble fms-like tyrosine kinase (sFlt-1), were performed at 12–16 and 28–32 weeks of pregnancy by enzyme immunoassay method. The study of the structural and functional features of the placenta and umbilical cord included sonographic and organometric methods. The variational statistical method of analysis of the obtained results was carried out using the «STATISTICA for Windows®-6.0» package.Results. In the women of the main group in the I trimester the ultrasound signs of pathology of the embryo and extraembryonic structures were significantly more often observed: low placement of the fertilized egg (33.8 %), its deformation (27.5 %), and partial detachment of the chorion (28.5 %). At 12–16 weeks of pregnancy, a pronounced vascular imbalance was established with a 2.5-fold decrease in the concentration of PlGF in the case of oligohydramnios compared to control data, a 1.8-fold decrease in the level of free VEGF-1 (in the case of oligohydramnios), and an increased level of antiangiogenic growth factors (sFlt-1).The postnatal examination of the placenta and umbilical cord showed that in the pregnant women of the main group a predominance of abnormal forms of placenta (16.3 %), a predominance of eccentric and marginal types of attachment of the umbilical cord (53.8 %), main and intermediate types of vascular branching (63.7 %), changes in the diameter of the umbilical cord (17.5 %), a combination of these features in a third of cases (31.3 %) were found. In the women of the main group, there was a decrease of the placental-fetal coefficient compared to the individuals of the control group, which was especially pronounced in pregnant women with oligohydramnios (up to 0.11±0.01 units compared to control data - 0.16±0.01 units).Conclusions. In the period of 12–16 weeks of pregnancy a vascular imbalance was established at the stage of placentation in patients who were diagnosed pathology of the perinatal environment at 30–32 weeks. In particular, by oligohydramnios there is a 2.5-fold decrease in the concentration of PlGF compared to the control data, a 1.8-fold decrease in the level of VEGF-1, and an increased antiangiogenic growth factor (sFlt-1), which became a prerequisite for the development of placental dysfunction.The results of the postnatal examination of the placenta and umbilical cord became an indirect reflection of placentation conditions. They demonstrated the predominance of abnormal forms, the predominance of the eccentric and marginal type of attachment of the umbilical cord, the main and intermediate type of vascular branching, an increased rate of umbilical cord pathology (Warton’s jelly deficiency, anomalies of the umbilical cord vessels) and a decreased placental-fetal ratio in women with amniotic fluid pathology, which was it is especially pronounced with oligohydramnios.

PS-C30-9: CHALLENGES IN MANAGING PERIPARTUM CARDIOMYOPATHY COMPLICATED WITH SEVERE PRE-ECLAMPSIA IN SUBURBAN AREA: A CASE REPORT

Background: Peripartum cardiomyopathy (PPCM) is a life-threatening condition, refers to rare dilated cardiomyopathy causing heart failure in late pregnancy or early postpartum woman. The diagnosis was based on pregnant/peripartum woman who had sudden cardiac decompensation without any history of cardiac disease. Pre-eclampsia (PE) could be co-existed with PPCM because of similar pathophysiology mechanism, which leads to higher mortality. Hereby we present the challenges of managing PPCM complicated with severe PE in suburban areas. Case Illustration: A 36-year-old woman referred to hospital with shortness of breath. Her past medical history was remarkable for severe-PE and had undergone caesarean section two-day-ago. Upon arrival, her saturation-75%, HR-120x/min, BP-140/80 and RR exceeds-40x/min. She was in respiratory distress with JVP increased, coarse crackles at basal lungs, and leg swelling. Laboratory studies were unremarkable. The x-ray revealed cardiomegaly and ECG showing LVH. Initial echocardiography demonstrated left ventricular systolic dysfunction with ejection fraction-34%. The patient was suggestive for PPCM with previous history of PE. Continuous administration of IV-furosemide-5 mg/h, spironolactone-25 mg, bisoprolol-2.5 mg, and candesartan-8 mg were administered. Her condition improved rapidly with increased saturation from 75% to 95% and significant reduced in dyspnoea. She was transferred to intensive cardiovascular unit for further management and discharged after 7-days for outpatient control. Discussion: PPCM is a devastated diagnosis among pregnancy woman. The diagnosis should be distinguish from PE induced heart failure. In PPCM, the echocardiography findings is related with left ventricular systolic dysfunction and reduced EF, whereas diastolic dysfunction with preserved EF is identified in PE induced heart failure patient. PE is associated with PPCM based on the shared pathophysiology. It is related with the angiogenic imbalance and excess expression of antiangiogenic factor sFlt1 soluble fms-like tyrosine kinase-1, which have found increased in both of the diseases. This is explained why PE has been recorded to occur in 30% of PPCM cases and it contributes to the increasing maternal mortality when most of the causes of maternal death are preventable.

Прогнозування і профілактика прееклампсії при багатоплідній вагітності після допоміжних репродуктивних технологій

Purpose - to assess the effectiveness of the implemented algorithm of treatment and preventive measures by analyzing the course of pregnancy, childbirth and the condition of newborns in multiple pregnancies after assisted reproductive technologies to assess of changes in biochemical markers of endothelial dysfunction in the detection of pre-clinical manifestations of preeclampsia in pregnant women with multiple pregnancies after the use of assisted reproductive technologies. Materials and methods. A prospective study of pregnant women with dichorionic diamniotic twins after assisted reproductive technologies was conducted: the Group І (main) - 35 pregnant women with twins who were offered a developed monitoring algorithm; the Group ІІ (control) 27 pregnant women who were monitored according to generally accepted methods of managing multiple pregnancies. Statistical processing of the research results was carried out using standard programs “Microsoft Excel 5.0” and “Statistica 6.0”. Results. In the Group І 2 cases of moderate preeclampsia were found in 32 and 33 weeks of pregnancy (PLGF results - 63.2 pg/ml and 58.7 pg/ml, sFlt-1/PLGF ratio - 51.7 and 66.3). In the Group II 4 cases of preeclampsia were identified: 2 cases of moderate preeclampsia (PLGF - 74.1 pg/ml and 69.3 pg/ml, sFlt-1/PLGF ratio - 98.6 and 104.5); 2 cases of severe preeclampsia at 33 and 34 weeks (PLGF data - 44.1 pg/ml and 47.3 pg/ml, sFlt-1/ PLGF ratio 122.4 and 130.1) against the background of signs of gestational hypertension. Fetal growth retardation in the Group І was noted in 3 (8.6%) women (І stage - in 2 (5.7%) cases, II stage - in 1 (2.9%) case, III stage was not diagnosed), in the Group II - in 7 (25.9%) women (I stage - in 2 (7.4%) cases, II stage - in 4 (14.8%) cases, III stage - in 1 (3.7%) case). Fetal distress in the Group І was detected in 4 (11.4%) pregnant women (during pregnancy - in 1 (2.9%) case, during deliveries - in 3 (8.6%) cases); in the Group II - in 7 (25.9%) women (during pregnancy - in 5 (18.5%) cases, during deliveries - in 2 (7.4%) cases). Premature deliveries in the Group I was noted in 5 (14.3%) women (before 34 weeks of gestation - in 2 (5.7%) cases, after 34 weeks of gestation - in 3 (8.6%) cases); in the Group II - in 8 (29.6%) women (before 34 weeks of gestation - in 5 (18.5%) cases, after 34 weeks of gestation - in 3 (11.1%) cases). Premature detachment of a normally located placenta was detected in 2 (7.4%) women in the Group II, and in the Group I such cases were not recorded. Vaginal delivery was observed in 14 (40%) women in the Group I and 7 (25.9%) patients in the Group II; cesarean section - in 21 (60%) and 19 (70.4%) women, respectively. Combined delivery was performed in 1 (3.7%) woman of the Group II, and in the Group I - not recorded. Hypoxic-ischemic lesions were detected in 2 (5.7%) children from women of the Group I and in 4 (14.8%) children from mothers of the Group II. Adaptation disorders were noted in 5 (14.3%) cases in the Group I and in 8 (29.6%) cases in the Group II. Transfer to the second stage of treatment required 3 (8.6%) children from mothers of the Group I and 6 (22.2%) children from mothers of the Group II. Conclusions. The proposed algorithm of modern diagnostic and treatment-prophylactic measures made it possible to reliably reduce the frequency of development of preeclampsia, obstetric and perinatal complications and can be recommended for use in practical health care. The study of the anti-angiogenic factor sFlt-1 and the pro-angiogenic factor PLGF and their ratio is promising in the prediction and early diagnosis of preeclampsia in multiple pregnancies after assisted reproductive technologies. The use of Triage PLGF and sFlt-1/PLGF ratio should be widely implemented in the practice of obstetrician-gynecologists as a prognostic marker for early recognition of preeclampsia in order to reduce perinatal complications, both from the mother and the fetus. Based on monitoring the growth dynamics of the sFlt-1/PLGF ratio, it is possible to predict the early development of preeclampsia even without clinical symptoms, and to make a decision about the possibility of extending the pregnancy or the need for urgent delivery. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the author.

Abstract P104: Neutralization Of Marinobufagenin Demonstrates Efficacy In Vitro And In Vivo In Models Of Preeclampsia

Objective: Marinobufagenin (MBG), a cardiotonic steroid, is distinctly elevated in preeclampsia (preE) and may directly contribute to pathogenesis, possibly through deleterious signaling in cytotrophoblast (CTB) cells. In this study, we evaluate the effects of anti-MBG human monoclonal antibodies on cellular signaling in CTB cells and in a rat model of preE. Methods: CTB cell proliferation in response to MBG with and without anti-MBG was measured using a Cell Titer assay. Pro-angiogenic factors (VEGF and PlGF) and anti-angiogenic factors (sFlt-1 and sEng) in response to MBG with and without antibody were measured. Finally, we evaluated the lead anti-MBG antibody in comparison with the parent murine antibody in a previously described rat model of preE which recapitulates the hypertension, proteinuria, and fetal growth effects of human preE. Results: CTB cells exposed to ≥ 1 nM MBG showed decreased ( p < 0.05) proliferation, decreased secretion of VEGF and PIGF, and increased secretion of sFlt-1 and sEng. Pretreatment with anti-MBG significantly ( p < 0.05) attenuated the MBG-induced modulation of cell proliferation and expression of VEGF, PIGF, sFlt-1, and sEng. In the rat model, anti-MBG treatment normalized blood pressure, reduced proteinuria, and eliminated fetal effects. Conclusions: MBG has the potential to be a causative agent for preE as it causes dysfunction in CTB cells due to the anti-angiogenic milieu. Our study suggests that anti-MBG antibodies can bind to MBG, neutralizing it, and preventing downstream signaling in vitro. In a saline-induced rat model of preE, treatment with anti-MBG antibody was effective at normalizing blood pressure, kidney function, and fetal birth weights. These data suggest that a human monoclonal antibody with high specificity and affinity for MBG has potential as a therapeutic for preE.

The Relationship between Angiogenic Factors and Energy Metabolism in Preeclampsia.

Antiangiogenic factors are currently used for the prediction of preeclampsia. The present study aimed to evaluate the relationship between antiangiogenic factors and lipid and carbohydrate metabolism in maternal plasma and placenta. We analyzed 56 pregnant women, 30 healthy and 26 with preeclampsia (including early and late onset). We compared antiangiogenic factors soluble Fms-like Tyrosine Kinase-1 (sfLt-1), placental growth factor (PlGF), and soluble endoglin (sEng)), lipid and carbohydrate metabolism in maternal plasma, and lipid metabolism in the placenta from assays of fatty acid oxidation, fatty acid esterification, and triglyceride levels in all groups. Antiangiogenic factors sFlt-1, sFlt-1/PlGF ratio, and sEng showed a positive correlation with triglyceride, free fatty acid, and C-peptide maternal serum levels. However, there was no relationship between angiogenic factors and placental lipid metabolism parameters. Free fatty acids were predictive of elevated sFlt-1 and sEng, while C-peptide was predictive of an elevated sFlt1/PlGF ratio. The findings in this study generate a model to predict elevated antiangiogenic factor values and the relationship between them with different products of lipid and carbohydrate metabolism in maternal serum and placenta in preeclampsia.

Chronic Hypoxia in Ovine Pregnancy Recapitulates Physiological and Molecular Markers of Preeclampsia in the Mother, Placenta, and Offspring.

Background:Preeclampsia continues to be a prevalent pregnancy complication and underlying mechanisms remain controversial. A common feature of preeclampsia is utero-placenta hypoxia. In contrast to the impact of hypoxia on the placenta and fetus, comparatively little is known about the maternal physiology.Methods:We adopted an integrative approach to investigate the inter-relationship between chronic hypoxia during pregnancy with maternal, placental, and fetal outcomes, common in preeclampsia. We exploited a novel technique using isobaric hypoxic chambers and in vivo continuous cardiovascular recording technology for measurement of blood pressure in sheep and studied the placental stress in response to hypoxia at cellular and subcellular levels.Results:Chronic hypoxia in ovine pregnancy promoted fetal growth restriction (FGR) with evidence of fetal brain-sparing, increased placental hypoxia-mediated oxidative damage, and activated placental stress response pathways. These changes were linked with dilation of the placental endoplasmic reticulum (ER) cisternae and increased placental expression of the antiangiogenic factors sFlt-1 (soluble fms-like tyrosine kinase 1) and sEng (soluble endoglin), combined with a shift towards an angiogenic imbalance in the maternal circulation. Chronic hypoxia further led to an increase in uteroplacental vascular resistance and the fall in maternal blood pressure with advancing gestation measured in normoxic pregnancy did not occur in hypoxic pregnancy.Conclusions:Therefore, we show in an ovine model of sea-level adverse pregnancy that chronic hypoxia recapitulates physiological and molecular features of preeclampsia in the mother, placenta, and offspring.

Preeclampsia associated changes in volume density of fetoplacental vessels in Chinese women and mouse model of preeclampsia

Preeclampsia (PE) is associated with abnormal placental vascular structure. However, the volume density of fetoplacental vessels in PE remains unclear. Additionally, manually annotated CT angiography, which is widely used to analyze placental vessels, has issues regarding inaccuracy. Thus, computer-aided CT angiography for analyzing the volume density of fetoplacental vessels would facilitate the understanding of PE pathogenesis. We performed computer-aided CT angiography to compare differences in placentas among 17 women with PE and 34 normotensive women. The contrast ratio in CT angiography was significantly enhanced using a three-dimensional (3-D) Hessian matrix algorithm. The PE-like mouse model was established by administration of 125mg/kg/day NG-nitro-l-arginine methyl ester (l-NAME) for 10 days. The presence of endothelial marker CD31 was confirmed by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC). The expression of angiogenic factors (PlGF, VEGFA, and sFlt1) in placentas was detected using qRT-PCR and western blotting. The volume density in fetoplacental vessels and CD31 expression were significantly reduced in women with PE and l-NAME-induced mice. Additionally, the downregulation of angiogenic factors (PlGF/VEGFA) and upregulation of an anti-angiogenic factor (sFlt1) were determined in a mouse model. Contrast-enhanced CT angiography with the aid of a 3-D Hessian matrix algorithm was performed. PE significantly affects the formation of vascular vessels, resulting in a lower volume density of fetoplacental vessels in humans and mice. This may be explained by the abnormal release of angiogenic factors during PE.

S-glutathionylation, a redox switch disrupting angiogenic balance to promote the preeclampsia phenotype

Abstract Background Elevation of circulating anti-angiogenic factors is pivotal in the development of the preeclampsia (PE) phenotype of incomplete vascular remodelling, hypertension and kidney dysfunction during pregnancy. Oxidative stress is explicitly linked to PE with high levels measurable in the placenta. Yet antioxidant therapy has failed, in some cases worsening pregnancy outcomes. The modulation of protein activity by reversible oxidative post-translational modifications (oxPTM) under low levels of reactive oxygen species is emerging as an important “redox-switch” mechanism in cardiovascular diseases, although oxPTM have not been investigated in the context of PE. Of significance, S-glutathionylation is a common oxPTM which reversal by glutaredoxin (Grx) is predominant in preeclamptic placenta and was associated with attenuated revascularisation and sFlt-1 elevation in mice. Purpose We aimed to identify the molecular basis for how S-glutathionylation reversal by Grx may contribute to pregnancy-induced vascular complications by modulating angiogenic signalling at the maternofoetal interface. Methods We combined physiological in vivo assessment with bioinformatics proteomic analysis and exon-level microarray to investigate the role of S-glutathionylation in the development of PE phenotype. In vitro studies using primary endothelial cells (EC) and iPS-derived trophoblasts investigated the effects of oxPTM reversal on angiogenic signalling in individual placental cell types and the functional consequences were assessed in 3D models replicating early-pregnancy events. Results Overexpressing Grx transgenic mice (TG) developed gestational hypertension, kidney dysfunction and elevated plasma levels of the anti-angiogenic factor sFlt-1 compared to their littermate controls (WT) during timed pregnancy. Grx-mediated oxPTM reversal in EC disrupted angiogenic sprouting and promoted anti-angiogenic signals by increasing sFlt-1:PlGF ratio and decreasing endoglin levels. The rise in sFlt-1 was associated with an isoform switch promoting sFlt-e15a over sFlt-i13. In trophoblasts, Grx overexpression inhibited migration and syncytialisation and modulated angiogenic balance in a cell type-specific manner. The sFlt1-e15a:PlGF ratio was increased in syncytiotrophoblasts and decreased in extra-villous trophoblasts, while endoglin expression was decreased in both cell types. A genome-wide exon-level profiling of TG vs WT mice placenta revealed a global alteration of alternative splicing events. Conclusion Grx-mediated removal of oxPTM directly disrupts placental angiogenic balance via dysregulation of sFlt-1 isoforms, which may promote the PE phenotype of impaired vascular remodelling, hypertension and kidney dysfunction during pregnancy. Funding Acknowledgement Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Horizon 2020 - Marie Skłodowska-Curie grant agreement (iPLACENTA)

Outcomes of pregnancies in women with extremely high ratio of sFlt-1 / PlGF: a series of clinical cases

Preeclampsia as one of the manifestations of placental dysfunction associated with dysregulation of pro- and antiangiogenic factors. During normal pregnancy, the concentration of antiangiogenic factor sFlt-1 remains low, which allows accurate transmission of signals induced by proangiogenic factors VEGF and PlGF. This balance is crucial to maintain physiological vasodilation. Under hypoperfusion, the placenta increases the synthesis of sFlt-1, trying to increase maternal pressure and increase placental perfusion.The objective: to study the clinical outcomes of pregnancies in a group with extremely high ratios of sFlt-1 and PlGF.Materials and methods. The results of determining the levels of placental growth factor (PlGF) and soluble fms-like tyrosine kinase (sfLT-1), which were performed during 2017-2020 in the serum of 128 pregnant women at 18–39 weeks, were analyzed.Results. The mean age of pregnant women was 28,4±4 years. The average gestational age during the study was 26±5 weeks. The majority of pregnant women had signs of IUGR (62,5%) and/or preeclampsia (50%) during the study. The average level of the sFlt/PIGF ratio was 1747 pg/ml. In 100% of cases with a digital ratio of more than 850, signs of an obstetric angiogenic catastrophe that required immediate delivery developed during the nearest future. The average time from analysis to delivery was 10 days. In 50% of pregnant women, urgent delivery was required within 48 hours after analysis. Favorable neonatal results were observed in 37,5% of women.Conclusion. We found a tendency for worsening perinatal outcomes in women with extremely high sFlt-1/PlGF ratios after reaching 850. Careful monitoring of the pregnant woman and consideration of need for prophylactic administration of corticosteroids to accelerate fetal lung maturation in this group is rational.

SERUM LEVELS OF SOLUBLE FMS –LIKE TYROSINE KINASE -1 IN PRE-ECLAMPTIC AND ECLAMPTIC CASES AND ITS CORRELATION TO FETOMATERNAL OUTCOME

Preeclampsia is a multisystem progressive disorder characterized by the new onset of hypertension and proteinuria or the new onset of hypertension and significant end-organ dysfunction with or without proteinuria after 20 weeks of gestation or postpartum in previously normotensive women. It is develops due to placental and maternal vascular dysfunction and disappears after delivery gradually by time. The incidence is estimated to be between 3 and 10% of all pregnancies.Maternal endothelial dysfunction which leads to pre-eclamptic signs and symptoms is induced by high levels of the antiangiogenic factor sFLT1, which is produced in the placenta and released into the maternal circulation. sFLT1 is a soluble splice variant of the membrane-bound receptor VEGFR1 that binds to the proangiogenic proteins VEGF and placental growth factor (PlGF); therefore, sFLT1 acts as a ligand trap and antagonizes ligand-mediated angiogenic signalling via the cell surface receptors. Aim of the workThe aim of this work was to evaluate serum levels of soluble fms-like tyrosine kinase-1 (sFlt-1) in cases of severe preeclampsia and eclamptic fits,and to correlate serum levels of soluble fms-like tyrosine kinase-1 (sFlt-1) in these cases to outcome of fetus and mother and incidence of complication.

Fas ligand neutralization attenuates hypertension, endothelin-1, and placental inflammation in an animal model of HELLP syndrome.

Neutralization of FasL is linked to suppression of hypertension, placental inflammation, and endothelin system activation in an animal model of hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome. During HELLP syndrome the placenta has been reported to serve as the primary source of Fas ligand (FasL), which has an impact on inflammation and hypertension during pregnancy and is dysregulated in women with severe preeclampsia and HELLP syndrome. We hypothesize that neutralization of FasL during pregnancy in an animal model of HELLP syndrome decreases inflammation and placental apoptosis, improves endothelial damage, and improves hypertension. On gestational day (GD) 12, rats were chronically infused with placental antiangiogenic factors sFlt-1 and sEng to induce HELLP syndrome. To neutralize FasL, MFL4 or FasL antibody was infused into a subset of HELLP or normal pregnant rats on GD13. IgG infusion into another group of NP and HELLP rats on GD13 was used as a control for FasL antibody, and all rats were euthanized on GD19 after blood pressure measurement. Plasma and placentas were collected to assess inflammation, apoptosis, and the degree of placental debris activation of endothelial cells. Administration of MFL4 to HELLP rats significantly decreased blood pressure compared with untreated HELLP rats and HELLP rats infused with IgG and improved the biochemistry of HELLP syndrome. Both circulating and placental FasL were significantly attenuated in response to MFL4 infusion, as were levels of placental and circulating TNFα when compared with untreated HELLP rats and HELLP rats infused with IgG. Endothelial cells exposed to placental debris and media from HP + MFL4 rats secreted significantly less endothelin-1 compared with stimulated endothelial cells from HELLP placentas. Neutralization of FasL is associated with decreased MAP and improvement in placental inflammation and endothelial damage in an animal model of HELLP syndrome.

The importance of antiangiogenic substances endoglin and sFLT-1, as well as endogenous digitalis-like factor marinobufagenin in the pathogenesis of preeclampsia

Objective. Establish the relationship between the action of antiangiogenic factors sFLT-1 and endoglin, as well as marinobufagenin in the formation of symptoms of preeclampsia in the clinic and experiment.
 Materials and methods. In the first experimental phase, preeclampsia-like state was simulated in pregnant rats, the changes in the content of substances reflected in the target tissues were studied, as well as the effect on their concentrations of anti-marinobufagenin antibodies. In the second (clinical) phase, changes in the content of sFlt-1 and endoglin-1 in placental tissues, as well as marinobufagenin in blood plasma and activity of Na+/K+-ATPase of erythrocytes in pregnant women with preeclampsia were studied.
 Results. In rats, an increase in systolic blood pressure, and marinobufagenin plasma levels was observed during the formation of a preeclampsia-like condition. Administration of antibodies to marinobufagenin caused a decrease in blood pressure. Found that during the formation of a preeclampsia-like condition, there is an increase in the content of sFlt-1 in the placenta and thoracic aorta and endoglin in the placenta. In patients with preeclampsia, it was found that the increase in blood pressure occurs against the background of an increase in the content of marinobufagenin in blood plasma, as well as a decrease in the activity of Na+/K+-ATPase of erythrocytes. The formation of preeclampsia is accompanied by a significant increase in the level of antiangiogenic factors endoglin and sFlt-1 in the placenta.
 Summary. In patients with preeclampsia, the development of clinical symptoms is accompanied by an increase in the placental tissues of the content of antiangiogenic factors endoglin and sFlt-1 and the content of marinobufagenin in blood plasma. The obtained data are confirmed by the results of an experiment performed on pregnant rats with modeling of preeclampsia-like condition.

Production of an anti-angiogenic factor sFLT1 is suppressed via promoter hypermethylation of FLT1 gene in choriocarcinoma cells

BackgroundSoluble Fms-like tyrosine kinase-1 (sFLT1) as an anti-angiogenic factor is abundantly expressed in placental trophoblasts. Choriocarcinoma, a malignant tumor derived from trophoblasts, is known to be highly angiogenic and metastatic. However, the molecular mechanism underlying angiogenesis in choriocarcinoma pathogenesis remains unclear. We aimed to investigate the mRNA expression and DNA methylation status of the FLT1 gene in human choriocarcinoma cells and trophoblast cells.MethodsqRT-PCR, Western blotting and ELISA were conducted to evaluate the mRNA and protein expression levels of sFLT1. 5-aza-2′-deoxycytidine (5azadC) treatment and bisulfite sequencing were used to study the FLT1 gene promoter methylation. The effect of sFLT1 on choriocarcinoma growth and angiogenesis was evaluated in a xenograft mouse model.ResultsExpression of the FLT1 gene was strongly suppressed in choriocarcinoma cell lines compared with that in the primary trophoblasts. Treatment of choriocarcinoma cell lines with 5azadC, a DNA methyltransferase inhibitor, markedly increased in mRNA expression of three FLT1 splice variants and secretion of sFLT1 proteins. Bisulfite sequencing revealed that the CpG hypermethylation was observed at the FLT1 promoter region in choriocarcinoma cell lines and a human primary choriocarcinoma tissue but not in human trophoblast cells. Interestingly, in 5azadC-treated choriocarcinoma cell lines, sFLT1 mRNA expression and sFLT1 production were further elevated by hypoxic stimulation. Finally, as expected, sFLT1-expressing choriocarcinoma cells implanted into nude mice showed significantly slower tumor growth and reduced microvessel formation compared with GFP-expressing control choriocarcinoma cells.ConclusionsInhibition of sFLT1 production by FLT1 silencing occurs via the hypermethylation of its promoter in choriocarcinoma cells. The stable expression of sFLT1 in choriocarcinoma cells resulted in the suppression of tumor growth and tumor vascularization in vivo. We suggest that the FLT1 gene may be a cell-type-specific tumor suppressor in choriocarcinoma cells.

A Promising Effect of Pravastatin For Reducing Preeclamsia Incidence In High Risk Pregnant Women

Preeclamsia is still a threat in obstetrics because it is the leading cause of maternal death (15-20% in developing countries). Globally, preeclampsia causes 70,000-80,000 pregnant women to die and 500,000 babies die annually1, with increased morbidity such as prematurity and fetal growth disturbance2. The exact cause of preeclampsia is still not clearly known (also called "The disease of theory"), but recent studies shows that the imbalance of pro-angiogenic (VEGF, PlGF) and anti-angiogenic factors (sFlt-1, s-Eng) plays an important role in the pathogenesis preeclampsia. The presence of general maternal endothelial dysfunction induced by an imbalance of these factors is a major phenomenon in preeclampsia, which results in placental hypoxia / ischemia, resulting in vasoconstriction resulting in hypertension1. Termination of pregnancy is still as a definitive therapy for preeclamsia. Therefore, early prevention is necessary in the management of preeclampsia. In 2013, ACOG recommended the administration of low-dose aspirin and calcium 1 gram / day to patients in pregnant women with high risk of preeclamsia3. However, low-dose aspirin is less useful in preventing preeclampsia in patients with a history of previous chronic hypertension4 and not reduce the incidence of term preeclampsia (the incidence of preeclampsia at gestational age above 37 weeks)5,6. This weakness of low-dose aspirin has led to recent research focusing on the prevention of preeclampsia. The similarity between the pathogenesis mechanism of preeclampsia and cardiovascular disease makes pravastatin (a protective therapy in cardiovascular disease before) as a potential agent for preventing preeclampsia7. Therefore, the role of pravastatin for reducing preeclampsia incidence in high risk pregnant women will be discussed in this article.

NAMPT levels are inversely related to nitric oxide formation and positively related to soluble fms-like tyrosine kinase-1 levels in preeclampsia.

NAMPT is a biomarker for endothelial dysfunction, but its relationship with nitrite (marker of NO formation) and soluble fms-like tyrosine kinase-1 (sFLT-1) has not been previously evaluated in preeclampsia. Therefore, we measured plasma NAMPT and sFLT-1 levels using enzyme immunoassays and plasma nitrite concentrations using an ozone-based chemiluminescence assay. NAMPT was positively correlated to nitrite (r = 0.217; P = 0.034) and inversely related to sFLT-1 (r = -0.340; P = 0.029) in healthy pregnant women, but inversely related to nitrite (r = -0.259; P = 0.035) and positively correlated to sFLT-1 (r = 0.326; P = 0.007) in preeclamptic patients, suggesting that NAMPT inhibits NO formation and interacts with the antiangiogenic factor sFLT-1 in preeclampsia.

Role of vascular growth factors as a regulator of angiogenesis processes at the stage of implantation potential formation in women with uterine factor infertility

Despite the broad discussion of clinical significance, the features of the etiopathogenesis of impaired implantation potential in women with uterine sinechias are described in individual works, there is no unanimous opinion on this issue among researchers. The objective: to find out the diagnostic value of a number of markers of the functional state of the endothelium and the level of individual induction angiogenesis in the formation of implantation potential in women with uterine infertility. Materials and methods. The evaluation of the endometrium was performed in 36 women with uterine senechias (first group) and 30 patients with long-term infertility and reproductive loss in history (second group). The control group included 20 healthy patients. This stage of scientific research was conducted taking into account the complex of instrumental methods – ultrasound, histological examination of endometrial biopsies obtained by hysteroscopy intervention, and/or fractional scissors in the dynamics of the menstrual cycle. The design of the study envisaged the study and evaluation of the level of individual factors of angiogenesis, in particular: vascular endothelial growth factor (VEGF-1), as well as antiangiogenic growth factor sFlt-1 and their fluctuations in the preconception phase in serum and cervical mucus. Results. The conducted researches allow to assert, that practically in all patients with uterine sinechia in the complex examination the predominance of the morphological picture of chronic endometritis, hyperplasia and endometrial polyposis, as well as inferior secretory transformation of the endometrium is established. The evaluation of the results of the histological study made it possible to diagnose the presence of hyperplastic processes in 36.1%, the so-called thin endometrium was verified at 19.4%, and the endometrium atrophy was found in 13.9% of the histological findings. The results obtained were demonstrated at the preconception stage in the reduction of VEGF-1 and the high anti-angiogenic growth factor sFlt-1: the level of said transmitter in the group of women with uterine senechias was 63% higher in controls than controls (2.8-fold) (p<0,05). Thus, in the case of deep pathomorphological lesions of the endometrium, at the stage of preconception preparation, there is a marked shift in the balance of vascular growth factors towards the increase in the concentration of antiangiogenic markers – sFlt-1, which is evidence of more severe impingement potential impairment in this category of patients. Conclusions. The level of vascular-endothelial growth factor in serum and cervical secretion as well as the estimation of the angiogenic factor may be early prognostic markers that characterize the initial signs of trophoblast invasion, occurring long before implantation impairment and clinical manifestation of non-compliance. It provides an opportunity to predict damage to the endometrium and its vascular network and can be used to control the effectiveness of preventive measures and the effectiveness of preconception training in women at risk for the implementation of possible underdeveloped pregnancy. Key words: uterine senechia, chronic endometritis, growth factors, angiogenic coefficient.