Anti-angiogenic Factors Research Articles

Vascular Disorders of Pregnancy Increase Susceptibility to Neonatal Pulmonary Hypertension in High-Altitude Populations.

Preeclampsia and fetal growth restriction increase cardiopulmonary disease risk for affected offspring and occur more frequently at high-altitude (≥2500 m). Retrospective studies indicate that birth to a preeclampsia woman at high altitude increases the risk of pulmonary hypertension (PH) in later life. This prospective study asked whether preeclampsia with or without fetal growth restriction exaggerated fetal hypoxia and impaired angiogenesis in the fetal lung, leading to neonatal cardiopulmonary circulation abnormalities and neonatal or infantile PH. We studied 79 maternal-infant pairs (39 preeclampsia, 40 controls) in Bolivia (3600-4100 m). Cord blood erythropoietin, hemoglobin, and umbilical artery and venous blood gases were measured as indices of fetal hypoxia. Maternal and cord plasma levels of angiogenic (VEGF [vascular endothelial growth factor]) and antiangiogenic (sFlt1 [soluble fms-like tyrosine kinase]) factors were determined. Postnatal echocardiography (1 week and 6-9 months) assessed pulmonary hemodynamics and PH. Preeclampsia augmented fetal hypoxia and increased the risk of PH in the neonate but not later in infancy. Pulmonary abnormalities were confined to preeclampsia cases with fetal growth restriction. Maternal and fetal plasma sFlt1 levels were higher in preeclampsia than controls and positively associated with PH. The effect of preeclampsia with fetal growth restriction to increase fetal hypoxia and sFlt1 levels may impede normal development of the pulmonary circulation at high altitude, leading to adverse neonatal pulmonary vascular outcomes. Our observations highlight important temporal windows for the prevention of pulmonary vascular disease among babies born to highland residents or those with exaggerated hypoxia in utero or newborn life.

STRATEGIC-1: Multi-line therapy trial in unresectable wild-type KRAS/NRAS/BRAF metastatic colorectal cancer—A GERCOR-PRODIGE randomized open-label phase III study.

3504 Background: The management of unresectable metastatic colorectal cancer (mCRC) is a comprehensive treatment strategy involving several lines of therapy, maintenance, salvage surgery, and treatment-free intervals. Besides chemotherapy (fluoropyrimidine, oxaliplatin, irinotecan), anti-angiogenic and anti-epidermal growth factor receptor (EGFR) agents have become available. Ultimately, strategy trials are needed to define the optimal use and the best sequencing of these agents. Methods: Patients with previously untreated RAS/BRAF wild-type unresectable mCRC were randomly assigned (1:1 ratio) to receive either FOLFIRI-cetuximab followed by mFOLFOX6-bevacizumab (arm A) or OPTIMOX-bevacizumab followed by FOLFIRI-bevacizumab followed by EGFR mab +/- irinotecan (arm B). This trial was designed as a superiority study (hypothesis arm B > arm A) with Duration of Disease Control (DDC) as primary endpoint, defined as the sum of PFS of each active sequence of treatment (Chibaudel B, J Clin Oncol, 2011). Secondary endpoints were overall survival (OS), Time to Failure of Strategy (TFS), Progression-free survival (PFS) and response rate (RECIST version 1.1) per sequence, salvage surgery rate, safety, and Quality of life (QoL). Results: Between October 2013 and May 2019, 263 eligible patients were randomized (arm A, n = 131; arm B, N = 132). After a median follow-up of 51.2 months (95% CI 43.3-57.4), 188 events for DDC were observed. Efficacy outcomes are presented in table. Median DDC was similar in both arms (HR 0.97, 95% CI 0.72-1.29; P = 0.805). Salvage surgery for metastasis (+/- radiofrequency ablation) was done in 36 (27.5%) patients in arm A and 28 (21.2%) in arm B. Median time until definitive deterioration of QoL (global health status) were 18.3 and 18.0 months (P = 0.628). The safety profiles were consistent with the established safety profiles of each treatment regimen. Conclusions: STRATEGIC-1 is the first randomized phase III study comparing multi-line standard treatment strategies in patients with KRAS/NRAS/BRAF wild-type mCRC. This study did not meet its primary endpoint of DDC. The treatment strategy starting with FOLFIRI-cetuximab followed by mFOLFOX6-bevacizumab led to higher response rates and to a trend for better median OS exceeding 3 years. These findings may add to our understanding of treatment sequencing in mCRC. Clinical trial information: NCT01910610. [Table: see text]

A phase 1 study of TPST-1120 as a single agent and in combination with nivolumab in subjects with advanced solid tumors.

3005 Background: TPST-1120 is a first-in-class oral therapy that inhibits PPARα, a transcription factor that regulates fatty acid oxidation (FAO). TPST-1120 has diverse mechanisms of anti-tumor activity in preclinical studies, including inhibiting tumor proliferation, increasing the anti-angiogenic factor thrombospondin 1, and reducing T cell exhaustion. Methods: Subjects with advanced solid tumor malignancies received escalating doses of TPST-1120 as a single agent or in combination with nivolumab 480 mg IV every 4 weeks (combination cohort limited to RCC, cholangiocarcinoma [CCA] and HCC). Study objectives included evaluation of safety, pharmacokinetics, MTD, RP2D and anti-tumor activity as monotherapy and in combination with nivolumab. AEs were assessed per CTCAE v5 and efficacy per RECIST v1.1 Results: As of 14-Jan-2022, 35 subjects have been dosed (20 with TPST-1120 monotherapy at doses from 100 mg to 600 mg PO BID and 15 in combination with nivolumab at doses from 200 mg to 600 mg PO BID). Median prior lines of systemic therapy were 3 (2-11) in monotherapy and 2 (2-6) in combination cohorts. An MTD was not reached in monotherapy or combination, and the TPST-1120 RP2D was 600 mg PO BID for both cohorts. For TPST-1120 monotherapy, the most common treatment related AEs (TRAEs) were nausea (20%), fatigue (15%), and diarrhea (10%), all Grade 1-2. One monotherapy subject (5%) experienced a Grade 3 TRAE (hypertension). In the combination cohort the most common TRAEs related to either drug were fatigue (40%), diarrhea (27%) and nausea (20%), all Grade 1-2. Three combination subjects (19%) experienced Grade 3 TRAEs (one each arthralgia, hepatic enzyme increased, muscle spasms). A best response of stable disease was observed in 53% (10/19) of subjects treated with monotherapy. In combination, the ORR was 23% (3/13, all PRs) across all dose levels and 38% (3/8) at TPST-1120 dose levels ≥400 mg BID. These responses included 2 subjects with late-line RCC (2/2 RCC subjects enrolled, both with progression on prior anti-PD1 therapy) and one subject with heavily pre-treated CCA. At data cut off, 2 of 3 responding patients (CCA and one RCC) remained in PR and on study at 8.4 and 14 mo, respectively. Conclusions: TPST-1120 is a novel therapy designed to inhibit tumor proliferation and angiogenesis and stimulate anti-cancer immunity through inhibition of PPARα, a key regulator of FAO. The drug is well tolerated as a single agent and in combination with nivolumab. Promising objective responses have been observed in combination with nivolumab in subjects previously refractory to anti-PD-1 therapy, including 2/2 responders in late-line RCC, and a subject with heavily pretreated CCA, a tumor type generally not responsive to anti-PD-1 alone. Notably, all responders were treated at the two highest doses of TPST-1120 (ORR 38%). Updated study results including exploratory biomarkers will be presented. Clinical trial information: NCT03829436.

Indicators of angiogenesis and hormonal profile in pregnant women with chronic hypertension in the first trimester

The role of angiogenesis factors and hormonal profile in pregnant women with arterial hypertension has not been detailed studied, and their interaction in such patients has not been determined at present time.The objective: to determine the features of angiogenesis factors and hormonal profile in pregnant women with arterial hypertension of the 1and 2 grade. Materials and methods. A prospective study was conducted in 88 pregnant women, which included: analysis of clinical and anamnestic characteristics and the study of pregnancy characteristics in women with chronic arterial hypertension (CAH) in the I trimester of pregnancy (11–12 weeks). The open prospective controlled study involved 61 pregnant women with CAH of the 1 and 2 stages which consisted the main group. The control group included 27 healthy pregnant women with physiological pregnancy. Concentrations of human chorionic gonadotropin (hCG), progesterone (PG), estradiol (E) and markers of angiogenesis – placental growth factor (PlGF) as a proangiogenic factor and soluble fms-like tyrosine kinase (sFlt-1) as an antiangiogenic factor were determined in the blood serum of all patients, sFlt-1/PGF ratio was also estimated (K). Statistical analysis was performed using «STATISTICA® for Windows 13.0».Results. In the I trimester of pregnancy in women with CAH, a shift in the balance between pro- and anti-angiogenic factors is determined, which is manifested by a statistically significant (p<0.05) increase sFlt-1 level (1700.9 pg/ml) and a decrease PlGF level in 3.7 times (9.1 pg/ml) and, accordingly, an increase K coefficient (sFlt-1/PlGF) by 5.3 times (184.5). The mean concentrations of E, PG and hCG in pregnant women of the main group did not differ statistically significantly from those in the control group. However, according to the results of the correlation analysis, PlGF and PG indicators have feedback in pregnant women with CAH (r=-0.29; p<0.05). When calculating the correlation of PlGF and hormones, it was found that in pregnant women with CAH there is their growth according to the control group, namely the indicator hCG correlates with PlGF (51.8 units vs. 14.8 units) 3.5 times, E correlates with PlGF (309.7 units vs. 70.0 units) 4.4 times and PG correlates with PlGF (4.8 units vs. 1.0 units) 4.8 times (p<0.001 for all indicators). These changes indicate the presence of angiogenesis disorders in pregnant women with chronic hypertension, starting from the I trimester of gestation.Conclusions. Pregnant women with CAH in the I trimester have disturbances in balance between pro-angiogenic and anti-angiogenic factors with prevalence of sFlt-1 and decrease of PlGF in blood serum. Because of such imbalance in pregnant women with CAH of the 1 and 2 grade, the interaction of angiogenesis factors and hormones changed from direct to inverse. It may lead to the development of placental dysfunction in the future, so treatment and prevention should be provided for the pregnant women with CAH in the I trimester.

Prospective directions for creating a strategy for effective medicine prevention of preeclampsia (Literature review)

Preeclampsia (PE) is a main cause of morbidity and mortality for both mother and fetus. The frequency of PE is from 2 % to 8 %. The complications which are related to PE lead to more than 50,000 maternal deaths and more than 500,000 fetal deaths worldwide each year. In Ukraine, PE was diagnosed in 11,075 women in 2020 (39.32 per 1,000 births), of which severe PE was diagnosed in 1,573 women (5.58 per 1,000 births).The advances in obstetrics and neonatology have significantly mitigated many adverse pregnancy outcomes associated with PE. The optimal prevention of PE is essential to prevent the morbidity and mortality associated with this pathology. The number of researches about new management for the prevention or treatment of PE and new drugs that can affect the pathophysiology of the disease increases. The main value of potential candidates for the prevention of PE is the preclinical impact on oxidative stress, antiangiogenic factors, as well as thrombogenic potential and proinflammatory pathways of pathology development. A systematic data search was carried out in MEDLINE, ISI Web of Science, PubMed, Scopus, Google Scholar and Proquest databases for 2014–2022. In this review, the results of preclinical and clinical studies about the rational prevention of the development of PE in pregnant women at risk with the involvement of the most promising drugs were analyzed. Preclinical studies have suggested new molecular targeting strategies, such as monoclonal antibodies directed against tumor necrosis factor alpha, placental growth factor, and short interfering ribonucleic acid technology to inhibit soluble fms-like tyrosine kinase-1 or angiotensinogen gene expression. Other treatment approaches that have progressed to phase III trials (either completed or ongoing) include proton pump inhibitors, metformin, nitric oxide donors and precursors, recombinant antithrombin III, digoxin immune antigen, and melatonin. There are cases suggesting that deletion of circulating soluble fms-like tyrosine kinase-1 can help to stabilize PE and prolong pregnancy.

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.

Studying molecular signaling in major angiogenic diseases.

The growth of blood vessels from already existing vasculature is angiogenesis and it is one of the fundamental processes in fetal development, tissue damage or repair, and the reproductive cycle. In a healthy person, angiogenesis is regulated by the balance between pro- and anti-angiogenic factors. However, when the balance is disturbed, it results in various diseases or disorders. The angiogenesis pathway is a sequential cascade and differs based on the stimuli. Therefore, targeting one of the factors involved in the process can help us find a therapeutic strategy to treat irregular angiogenesis. In the past three decades of cancer research, angiogenesis has been at its peak, where an anti-angiogenic agent inhibiting vascular endothelial growth factor acts as a promising substance to treat cancer. In addition, cancer can be assessed based on the expression of angiogenic factors and its response to therapies. Angiogenesis is important for all tissues, which might be normal or pathologically changed and occur through ages. In clinical therapeutics, target therapy focusing on discovery of novel anti-angiogenic agents like bevacizumab, cetuximab, sunitinib, imatinib, lenvatinib, thalidomide, everolimus etc., to block or inhibit the angiogenesis pathway is well explored in recent times. In this review, we will discuss about the molecular signaling pathways involved in major angiogenic diseases in detail.

SEC is an antiangiogenic virulence factor that promotes Staphylococcus aureus endocarditis independent of superantigen activity.

The superantigen staphylococcal enterotoxin C (SEC) is critical for Staphylococcus aureus infective endocarditis (SAIE) in rabbits. Superantigenicity, its hallmark function, was proposed to be a major underlying mechanism driving SAIE but was not directly tested. With the use of S. aureus MW2 expressing SEC toxoids, we show that superantigenicity does not sufficiently account for vegetation growth, myocardial inflammation, and acute kidney injury in the rabbit model of native valve SAIE. These results highlight the critical contribution of an alternative function of superantigens to SAIE. In support of this, we provide evidence that SEC exerts antiangiogenic effects by inhibiting branching microvessel formation in an ex vivo rabbit aortic ring model and by inhibiting endothelial cell expression of one of the most potent mediators of angiogenesis, VEGF-A. SEC’s ability to interfere with tissue revascularization and remodeling after injury serves as a mechanism to promote SAIE and its life-threatening systemic pathologies.

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.

MicroRNA-135b-5p regulates trophoblast cell function by targeting phosphoinositide-3-kinase regulatory subunit 2 in preeclampsia

ABSTRACT The level of miR‑135b-5p is lower in patients with preeclampsia (PE) superimposed on chronic hypertension than in healthy controls. However, the function of miR‑135b-5p in PE progression remains unknown. In the present study, we investigated the role of miR‑135b-5p in PE development and its possible mechanism for the first time. HTR8/SVneo cells (trophoblast cell line) were exposed to hypoxia/reoxygenation (H/R) to mimic PE in vitro. Hypoxia-inducible factor-1α (HIF-1α), forkhead box O3A (FOXO3a), and miR-135b-5p levels were measured using Real-time PCR. Cell proliferation, apoptosis and migration/invasion were evaluated using the Cell Counting Kit-8 (CCK-8), flow cytometry and transwell assays, respectively. Real-time PCR and Western blotting were performed to determine the levels of several pro- and anti-angiogenic factors. The binding of miR-135b-5p to the PIK3R2-3’ untranslated region (3ʹUTR) was confirmed by bioinformatics analysis and a dual-luciferase reporter assay. H/R exposure greatly upregulated HIF-1α, FOXO3a, and PIK3R2 levels, while downregulating miR-135b-5p levels in HTR8/SVneo cells. H/R exposure resulted in the inhibition of proliferation, migration, invasion, angiogenesis, and the induction of apoptosis. MiR-135b-5p overexpression reversed the effects of H/R on trophoblast cell function, while miR-135b-5p knockdown enhanced the effects. PIK3R2 knockdown had similar effects as miR-135b-5p overexpression on proliferation, apoptosis and angiogenesis. The effect of miR-135b-5p overexpression on H/R-exposed cells was enhanced by PIK3R2 knockdown. MiR-135b-5p downregulated PIK3R2 expression by pairing with its 3ʹUTR. Therefore, miR-135b-5p may regulate trophoblast function by targeting PIK3R2 in PE and could serve as a novel therapeutic target for PE.

Syncytialization of BeWo trophoblasts induces changes in angiogenic signaling and response to hypoxia

During pregnancy, the placenta produces significant amounts of pro and anti‐angiogenic factors, notably VEGF, PlGF, and sFlt‐1. The exact cell population(s) most responsible for this production is not definitively known. In the event of placental insufficiency, placental ischemia can cause alterations in the production of these factors, favoring the anti‐angiogenic sFlt‐1 protein. This mechanism is believed to be a major driver of preeclampsia. Within the placenta, the maternal/fetal interface is defined by a layer of specialized syncytiotrophoblasts (ST) which line the maternal side of the underlying fetal chorionic vessels. These large multinucleated cells define the selectivity of nutrient/waste exchange from the maternal to the fetal circulation. In studying trophoblast function, immortalized trophoblast‐derived cell lines are commonly utilized, such as the BeWo choriocarcinoma cell line. These cells however, do not spontaneously syncytialize, and therefore do not likely reflect in vivo ST function. We hypothesized that inducing syncytialization of BeWo cells would alter their production of angiogenic factors in vitro. Syncytialization of BeWo cells was induced with forskolin treatment for 48 hours. At 48 hours, cellular morphology shifted from dense cobblestone patterning into majority large, multinucleated cells. Syncytialization caused ~5 fold increase in both VEGF and PlGF mRNA (p<0.0001). There were significant (p<0.0001) increases in the levels of sFlt‐1 splice variants 2 (~5 fold), 3 (~50 fold), and 4 (~3fold). As a result, there were significant (p,<0.005) ~2 fold increases in secreted VEGF and PlGF protein, while sFlt‐1 went from not detectable to 53 pg/ml as measured by ELISA. Perhaps most interestingly, when cultured in oxygen concentrations mimicking healthy and ischemic placentas (8% and 1% respectively), there was differential regulation of these factors at the transcriptional level. There was no change in VEGF, while sFlt V2 and V3 were significantly upregulated (2‐fold each, p<0.0005), while PlGF was significantly down regulated by 40% (p<0.0001). Taken together, these data suggest that syncytialization significantly alters expression of both pro and anti‐angiogenic factors in vitro. Future studies should take syncytialization state into account when extrapolating from cell culture to in vivo placental function.

Effects of pharmacologic interventions on hypertension attenuation and growth factors in animal model

Studies in hypertensive models of pregnancy have reported improvement in pregnancy outcomes and mean arterial pressure (MAP) after administration of various pharmacological agents. Circulating anti‐angiogenic and placental growth factors are often used as biomarkers for placental dysfunction, however the effect of pharmacological intervention to reduce hypertension on placental function is still not clear. Therefore our objective was to determine if attenuation of hypertension during a hypertensive pregnancy is associated with an improvement in placental function. To address this question we used placentas that were collected from previous pharmacological studies and stored at ‐80°C. Timed‐pregnant Sprague Dawley rats arrived on gestational day (GD) 11 and either remained normotensive (NP) or were implanted with a mini‐osmotic pump on GD12 infusing sFlt‐1 and sEng (4.7 & 7ug/kg respectively). Rats were treated with 5mg/kg ABT‐627 (blockade of the ETAreceptor), 5mg/kg Tempol (TEM, superoxide dismutase mimetic), 2mg/kg Orencia (T‐cell depletion), 500ng/kg of MFL4 (neutralization of FasL) or 100pg/day IL‐17 soluble RC (blockade of the IL‐17) for variable times during pregnancy. On GD19 MAP was measured, pups were weighed and organs were stored for future use. Placentas (n=4‐5) were homogenized and assayed in individual ELISAs for the following growth factors: sFlt‐1, PlGF, VEGF and sEng. As expected pharmacological treatments significantly decreased MAP relative to hypertensive rats (p=0.005). When the placental sFlt‐1/PlGF ratio was evaluated it was only significantly decreased in response to TEM (p=0.05). sEng was significantly decreased in rats receiving either Orencia (p=0.004) or IL‐17RC (p=0.003). There were no statistically significant differences between hypertensive rats and treated rats in any other individual factors (p>0.05). Additionally, there was a negative correlation between MAP and pup weight (r=‐0.24, p=0.03) and placental weight (r=‐0.24, p=0.03). However there was not a significant positive correlation was found between MAP and the sFlt‐1/PlGF ratio (r = 0.12, p=0.38). Collectively these data indicate that while the selected pharmacological interventions were effective at lowering the blood pressure, the effect on growth factors associated with placental dysfunction was variable. In conclusion, the role of different pharmacological interventions on improving placental dysfunction remains unclear suggesting the need for further studies to evaluate the impact of other pharmacological interventions on placental dysfunction and pregnancy outcomes.

CXCL10 is a novel anti-angiogenic factor downstream of p53 in cardiomyocytes.

Tumor suppressor protein p53 plays crucial roles in the onset of heart failure. p53 activation results in cardiac dysfunction, at least partially by suppressing angiogenesis. Though p53 has been reported to reduce VEGF production by inhibiting hypoxia‐inducible factor, the anti‐angiogenic property of p53 remains to be fully elucidated in cardiomyocytes. To explore the molecular signals downstream of p53 that regulate vascular function, especially under normoxic conditions, DNA microarray was performed using p53‐overexpressing rat neonatal cardiomyocytes. Among genes induced by more than 2‐fold, we focused on CXCL10, an anti‐angiogenic chemokine. Real‐time PCR revealed that p53 upregulated the CXCL10 expression as well as p21, a well‐known downstream target of p53. Since p53 is known to be activated by doxorubicin (Doxo), we examined the effects of Doxo on the expression of CXCL10 and found that Doxo enhanced the CXCL10 expression, accompanied by p53 induction. Importantly, Doxo‐induced CXCL10 was abrogated by siRNA knockdown of p53, indicating that p53 activation is necessary for Doxo‐induced CXCL10. Next, we examined the effect of hypoxic condition on p53‐mediated induction of CXCL10. Interestingly, CXCL10 was induced by hypoxia and its induction was potentiated by the overexpression of p53. Finally, the conditioned media from cultured cardiomyocytes expressing p53 decreased the tube formation of endothelial cells compared with control, analyzed by angiogenesis assay. However, the inhibition of CXCR3, the receptor of CXCL10, restored the tube formation. These data indicate that CXCL10 is a novel anti‐angiogenic factor downstream of p53 in cardiomyocytes and could contribute to the suppression of vascular function by p53.

Diagnosis and Management of Preeclampsia: Suggested Guidance on the Use of Biomarkers.

It is a challenge to consider preeclampsia (PE) diagnosis and management in low and middle-income settings, where it represents a major public health concern. The placenta is the underlying cause of disease, and the plasma concentrations of proangiogenic and antiangiogenic factors released by the placenta can reflect the risks of disease progression. Antiangiogenic proteins, such as soluble fms-like tyrosine kinase 1 (sFlt-1), and proangiogenic, like placental growth factors (PlGF), are directly and inversely correlated with the disease onset, respectively. Narrative review on the use of biomarkers (sFlt-1 to PlGF ratio) with a suggested guidance protocol. Key considerations on the use of biomarkers: the sFlt-1/PlGF ratio is mainly relevant to rule out PE between 20 and 36 6/7 weeks in cases of suspected PE; however, it should not replace the routine exams for the diagnosis of PE. The sFlt-1/PlGF ratio should not be performed after confirmed PE diagnosis (only in research settings). In women with suspected PE, sFlt-1/PlGF ratio < 38 can rule out the diagnosis of PE for 1 week (VPN = 99.3) and up to 4 weeks (VPN= 94.3); sFlt-1/PlGF ratio > 38 does not confirm the diagnosis of PE; however, it can assist clinical management. In cases of severe hypertension and/or symptoms (imminent eclampsia), hospitalization is imperative, regardless of the result of the sFlt-1/PlGF ratio. The use of biomarkers can help support clinical decisions on the management of suspected PE cases, especially to rule out PE diagnosis, thus avoiding unnecessary interventions, especially hospitalizations and elective prematurity.

Pigment Epithelium-Derived Factor-Loaded PEGylated Nanoparticles as a New Antiangiogenic Therapy for Neovascularization.

Background Pathological neovascularization, which involves a disruption in the balance between angiogenic and antiangiogenic factors under pathological conditions, is the basis of many intraocular diseases. Pigment epithelium-derived factor (PEDF) is a potent natural, endogenous inhibitor of neovascularization because of its antiangiogenic and neuroprotective benefits. However, its application is restricted by its instability and short half-life. The present study is aimed at investigating the cytotoxicity and antiangiogenic effects of PEDF-loaded PEGylated nanoparticles (NP-PEG-PEDF) on high glucose-stimulated human umbilical vein endothelial cells (HUVECs). Methods In this study, NP-PEG-PEDF were fabricated using the multiple emulsion method for the first time. HUVECs were cultured in a high concentration of glucose (30 mmol/L D-glucose), simulating diabetic conditions. The antiangiogenic effects of vascular endothelial growth factor (VEGF), pure PEDF, and NP-PEG-PEDF on proliferation, migration, and tube formation were evaluated. VEGF secretion in high glucose-stimulated HUVECs was further tested in vitro. Results NP-PEG-PEDF exhibited low cytotoxicity in HUVECs. Our results indicated that in vitro, NP-PEG-PEDF attenuated diabetes-induced HUVEC proliferation, migration, and tube formation and suppressed VEGF secretion. The apoptosis of diabetes-induced HUVECs occurred in a dose-dependent manner, which showed a statistically significant difference compared with the PEDF treatment group. Conclusion Our study is the first to demonstrate that NP-PEG-PEDF exert antiangiogenic effects on high glucose-stimulated HUVECs and have the potential to alleviate microvascular dysfunction. These data suggest that the NP-PEG-PEDF delivery system may offer an innovative therapeutic strategy for preventing neovascularization of the fundus.

Inhibition of oxidative stress delays senescence and augments functional capacity of endothelial progenitor cells

Ageing is characterised by a progressive loss of vascular endothelial function and integrity. Endothelial progenitor cells (EPCs) play an integral role in endothelial regeneration but are prone to age-dependent changes which may accelerate their senescence and diminish their availability and functionality. Considering these, we firstly investigated the quantity of circulating EPCs in older (73.3 ± 7.2 years) and younger (40.2 ± 14.3 years) healthy volunteers and showed sharp declines in the number of EPCs expressing stemness markers (CD34 + and/or CD133 + ) in older people. These coincided with the decreases in total anti-oxidant capacity (TAC) and concomitant increases in plasma levels of pro-inflammatory cytokine, TNF-α and anti-angiogenic factor, endostatin and thrombospondin-1. The subsequent experimental studies to scrutinise the effect of ageing on molecular and functional properties of outgrowth endothelial cells (OECs), the functional subtype of EPCs, showed that chronological ageing, mimicked by replicative senescence, profoundly impaired proliferation, migration, tubulogenesis, and blood–brain barrier (BBB)-forming capacity of these cells. Similar to those seen in the clinical observational studies, senescent OECs also manifested decreased TAC and increased pro-oxidant NADPH oxidase activity and endostatin level. Suppressing oxidative stress level using structurally and functionally distinct anti-oxidants, namely vitamin C or VAS2870, an NADPH oxidase inhibitor, delayed OEC senescence and restored their tubulogenic and BBB-forming capacities. In conclusion, the enhanced oxidative stress level that develops during physiological ageing may promote EPC senescence and evoke endothelial dysfunction. Effective control of oxidative stress using either compound somewhat delays both phenomena and augments EPC functionality.

The Imbalance Angiogenic and Anti-angiogenic Signalings in Placenta Accreta Spectrum

Spectrum placenta accreta was defined as a disruption in the attachment of the trophoblast to the myometrium directly without the presence of a decidua or basement membrane between them. During the early stages of placenta formation, trophoblast invasion is disturbed in the spectrum of placenta accreta. Changes in the structure of the tissue in the uterine scar following surgery or curettage may cause these problems. The invasion of trophoblasts is linked to the processes of vasculogenesis and angiogenesis. This process requires a balance between angiogenic factors and anti-angiogenic factors to produce a good placentation process. In the spectrum of placenta accreta, it is suspected that there is an imbalance between angiogenic factors and anti-angiogenic factors. This has an impact on the ability of trophoblast invasion since the beginning of the formation of the placenta. This study reviews the role of angiogenesis and anti-angiogenesis in the placenta accreta spectrum. A narrative review is done by reviewing some literature that discusses angiogenesis and anti-angiogenesis processes in the placenta accreta spectrum. The search was performed using placenta accreta spectrum, angiogenesis and anti-angiogenesis processes keywords in the PubMed, Google Scholar, and ScienceDirect databases. The collected data is then arranged in a narrative manner.

Kidney-placenta crosstalk in health and disease.

ABSTRACTOrgan crosstalk allows the interaction between systems to adapt to a constant changing environment, maintaining homeostasis. The process of placentation and the new hormonal environment during pregnancy trigger physiological changes that modulate kidney function to control extracellular volume, acid–base balance and filtration of metabolic waste products. The bidirectional communication means that acute or chronic dysfunction of one organ can compromise the other. Abnormal placentation in pregnancy-related hypertensive disorders such as pre-eclampsia and HELLP (haemolysis, elevated liver enzymes and low platelet count) syndrome leads to the release of antiangiogenic factors that may cause kidney injury (thrombotic microangiopathy, glomeruloendotheliosis, mesangiolysis and vasoconstriction of peritubular vessels). These hypertensive disorders are a key cause of kidney injury in gestation, which increases maternal morbimortality and adverse foetal outcomes. Conversely, prior kidney injury or causes of kidney injury (diabetes, lupus, glomerulonephritis or other forms of chronic kidney disease) increase the risk of developing hypertensive pregnancy disorders, providing a baseline higher risk. Inherited kidney diseases are a special concern, given the potential for genetic predisposition to kidney disease in the foetus. Understanding the bidirectional potential for compromise from placenta to kidney and vice versa provides a better framework to limit damage to both organs and improve maternal and foetal outcomes.

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.

New approaches for solving the old problem

Infantile hemangioma (IH) is a benign vascular tumor with abnormal proliferation of endothelial cells and impaired vascular architecture. It is believed that the pathogenesis of IH is based on angiogenesis impairment caused by imbalance between angiogenic and anti-angiogenic factors. Despite spontaneous regression, which is observed in 90% of cases of IH, several tumor localizations may indicate the possibility of systemic manifestations or lead to the development of complications that require medical interventions. Here we report 2 cases of the most frequent and severe complications of IH and the first successful use of combined treatment strategy including metronomic chemotherapy (cyclophosphamide plus vinblastine) and nonselective b-blocker (propranolol) in IH. The parents of the patients agreed to use the information, including the photographs of children, in scientific research and publications. In contrast to glucocorticoids commonly used in clinical practice for complicated forms of IH, metronomic chemotherapy showed high efficacy and safety. It led to a rapid, within the first two weeks, clinical improvement resulting not only in stopping tumor growth, but even in size reduction. Such a rapid response to therapy allowed to stop the development of ulcers and necrosis with secondary infection, and to prevent severe vital complications of IH such as the upper respiratory tract compression.