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10 p.- 1 fig., C. Bernabeu acknowledges support from Consejo Superior de Investigaciones Científicas (CSIC) of Spain (201920E022).

Purpose: The purpose of this study was to investigate the relationships among plasma concentrations of lenvatinib, angiopoietin (Ang)-1 and Ang-2, and clinical responses to lenvatinib therapy in Japanese patients with thyroid cancer. Methods: Plasma concentrations of lenvatinib (C0) and Ang-1 and -2 were measured by HPLC and ELISA, respectively.Results: The median change rates of Ang-1 and Ang-2 at 1 month after treatment from baseline in 36 patients were -15.3% and -48.4%, respectively. However, the change of Ang-1 and Ang-2 at 1 month from baseline did not correlate with lenvatinib C0. In patients with partial response (PR) and stable disease to lenvatinib, Ang-2 at 1 month were significantly lower than Ang-2 at baseline (P < 0.001 and P < 0.05, respectively), but were not significantly lower in patients with progressive disease. The area under the ROC for PR prediction was 0.667, giving the best sensitivity (69.2%) and specificity (73.9%) at a threshold of the change rate of Ang-2 of -49.83%. A one year overall survival for patients having the change rate of Ang-2 of at least -49.83% and less than -49.83% were 62.5% and 40%, respectively. In patients who continued treatment with lenvatinib for 1 year, Ang-2 at 1 month and 1 year after treatment were significantly lower than those at baseline (each P < 0.001).Conclusion: The change of Ang-2 at 1 month after treatment from baseline rather than simply the Ang-2 level at baseline may be important as a biomarker of the inhibitory effect of angiogenesis by lenvatinib.

Hemorrhagic shock causes an immediate decrease in microcirculatory perfusion, which cannot be restored by standard therapy with fluids and blood products. The disturbance in microcirculatory perfusion is suggested to be the underlying cause of multiple organ failure, leading to increased mortality. To date, additional treatment strategies to restore microcirculatory perfusion following hemorrhagic shock are lacking. The endothelium is a semi-permeable barrier that covers the inner layer of the microvasculature, where it tightly regulates the exchange of fluids, nutrients and waste products between blood and tissue. In this thesis, we propose the microvascular endothelium as central regulator of hemorrhagic shock-induced microcirculatory perfusion disturbances. We investigated the effect of hemorrhagic shock and fluid resuscitation on endothelial barrier function and microcirculatory perfusion. Subsequently, we investigated which molecular mechanisms are of interest as target to reduce microvascular leakage and restore microcirculatory perfusion following hemorrhagic shock. Due to the central role of the endothelium, we propose the endothelial angiopoietin/Tie2 system, a key regulator of endothelial barrier function, as target to reduce microvascular leakage following hemorrhagic shock. The angiopoietin/Tie2 system consists of several components, of which the ligands angiopoietin-1 and angiopoietin-2 and the Tie2 receptor are mostly investigated. Under healthy conditions, angiopoietin-1 binds to the Tie2 receptor which subsequently leads to activation of the downstream pathway, thereby maintaining endothelial barrier function. A stress response, such as inflammation, excessively releases angiopoietin-2 which competitively binds the Tie2 receptor, blocking activation of the Tie2 receptor and disrupting endothelial barrier function. In this thesis, we investigated the effect of dysregulation of the angiopoietin/Tie2 system on microvascular integrity in mice. Subsequently, with the use of a rat model representing hemorrhagic shock and fluid resuscitation, we investigated whether restoring the imbalance in the angiopoietin/Tie2 system could reduce microvascular leakage and thereby restore microcirculatory perfusion following hemorrhagic shock and fluid resuscitation. Finally, we investigated whether there are sex-related differences in the regulation of the angiopoietin/Tie2 system.

Hemorrhagic shock causes an immediate decrease in microcirculatory perfusion, which cannot be restored by standard therapy with fluids and blood products. The disturbance in microcirculatory perfusion is suggested to be the underlying cause of multiple organ failure, leading to increased mortality. To date, additional treatment strategies to restore microcirculatory perfusion following hemorrhagic shock are lacking. The endothelium is a semi-permeable barrier that covers the inner layer of the microvasculature, where it tightly regulates the exchange of fluids, nutrients and waste products between blood and tissue. In this thesis, we propose the microvascular endothelium as central regulator of hemorrhagic shock-induced microcirculatory perfusion disturbances. We investigated the effect of hemorrhagic shock and fluid resuscitation on endothelial barrier function and microcirculatory perfusion. Subsequently, we investigated which molecular mechanisms are of interest as target to reduce microvascular leakage and restore microcirculatory perfusion following hemorrhagic shock. Due to the central role of the endothelium, we propose the endothelial angiopoietin/Tie2 system, a key regulator of endothelial barrier function, as target to reduce microvascular leakage following hemorrhagic shock. The angiopoietin/Tie2 system consists of several components, of which the ligands angiopoietin-1 and angiopoietin-2 and the Tie2 receptor are mostly investigated. Under healthy conditions, angiopoietin-1 binds to the Tie2 receptor which subsequently leads to activation of the downstream pathway, thereby maintaining endothelial barrier function. A stress response, such as inflammation, excessively releases angiopoietin-2 which competitively binds the Tie2 receptor, blocking activation of the Tie2 receptor and disrupting endothelial barrier function. In this thesis, we investigated the effect of dysregulation of the angiopoietin/Tie2 system on microvascular integrity in mice. Subsequently, with the use of a rat model representing hemorrhagic shock and fluid resuscitation, we investigated whether restoring the imbalance in the angiopoietin/Tie2 system could reduce microvascular leakage and thereby restore microcirculatory perfusion following hemorrhagic shock and fluid resuscitation. Finally, we investigated whether there are sex-related differences in the regulation of the angiopoietin/Tie2 system.

Summary Background The relationship between acute respiratory distress syndrome (ARDS)/acute lung injury (ALI) and levels of certain inflammatory factors remains controversial. The purpose of this meta-analysis was to summarize the available studies evaluating the association between levels of inflammatory factors and ARDS/ALI incidence. Methods We searched the PubMed, EmBase, and Cochrane databases for studies published up to July 2017. For each inflammatory factor, a random effects model was employed to pool results from different studies. Results We identified 63 studies that included 6243 patients in our meta-analysis. Overall, the results indicated that the levels of angiopoietin (ANG)-2 (standard mean difference, SMD: 1.34; P P = 0.012), IL‑6 (SMD: 0.66; P = 0.005), and tumor necrosis factor (TNF)-α (SMD: 0.98; P = 0.001) were significantly higher in patients with ARDS/ALI than in unaffected individuals. No significant differences were observed between patients with ARDS/ALI and unaffected individuals in terms of the levels of IL‑8 (SMD: 0.61; P = 0.159), IL-10 (SMD: 1.10; P = 0.231), and plasminogen activator inhibitor (PAI)-1 (SMD: 0.70; P = 0.060). Conclusions ARDS/ALI is associated with a significantly elevated levels of ANG‑2, IL-1β, IL‑6, and TNF‑α, but not with IL‑8, IL-10, and PAI‑1 levels.

AIM: To quantitatively detect aqueous levels of angiopoietin-like (ANGPTL)3, ANGPTL4, and ANGPTL6 and investigate their correlation with optical coherence tomography angiography (OCTA) findings in patients with diabetic macular edema (DME). METHODS: This cross-sectional study included 23 patients (27 eyes) with type 2 diabetes and 16 control subjects (20 eyes). All patients underwent OCTA imaging and ultra-wide field fundus photography. Diabetic patients were categorized into two groups according to the presence or absence of diabetic retinopathy (DME group, 14 patients, 16 eyes); and non-diabetic retinopathy (NDR) group, 9 patients, 11 eyes, respectively. Aqueous levels of ANGPTL3, ANGPTL4, and ANGPTL6 were assessed using suspension array technology, and foveal-centered 3×3 mm2 OCTA scans were automatically graded to determine the central, inner, and full vessel density (CVD, IVD, FVD); central, inner, and full perfusion density (CPD, IPD, FPD), foveal avascular zone (FAZ) area, FAZ perimeter, and FAZ circularity index (FAZ-CI) on superficial capillary plexuses. Additionally, central subfield thickness (CST), cube volume (CV), and cube average thickness (CAT) were measured in a model of macular cube 512×128. RESULTS: Aqueous ANGPTL3 levels were not significantly different among the three groups (P>0.05). ANGPTL4 levels were significantly higher in the DME group than the control and NDR groups (P

Background Familial partial lipodystrophy (FPLD) is a rare disease characterized by selective loss of peripheral subcutaneous fat, associated with dyslipidemia and diabetes mellitus. Reductions in circulating levels of ANGPTL3 are associated with lower triglyceride and other atherogenic lipids, making it an attractive target for treatment of FPLD patients. This proof-of-concept study was conducted to assess the efficacy and safety of targeting ANGPTL3 with vupanorsen in patients with FPLD. Methods This was an open-label study. Four patients with FPLD (two with pathogenic variants in LMNA gene, and two with no causative genetic variant), diabetes (HbA1c ≥ 7.0 % and ≤ 12 %), hypertriglyceridemia (≥ 500 mg/dL), and hepatic steatosis (hepatic fat fraction, HFF ≥ 6.4 %) were included. Patients received vupanorsen subcutaneously at a dose of 20 mg weekly for 26 weeks. The primary endpoint was the percent change from baseline in fasting triglycerides at Week 27. Other endpoints analyzed at the same time point included changes in ANGPTL3, fasting lipids and lipoproteins, insulin secretion/sensitivity, postprandial lipids, and glycemic changes in response to a mixed meal test, HFF measured by MRI, and body composition measured by dual-energy absorptiometry (DEXA). Results Baseline mean ± SD fasting triglyceride level was 9.24 ± 4.9 mmol/L (817.8 ± 431.9 mg/dL). Treatment resulted in reduction in fasting levels of triglycerides by 59.9 %, ANGPTL3 by 54.7 %, and in several other lipoproteins/lipids, including very low-density lipoprotein cholesterol by 53.5 %, non-high-density lipoprotein cholesterol by 20.9 %, and free fatty acids (FFA) by 41.7 %. The area under the curve for postprandial triglycerides, FFA, and glucose was reduced by 60 %, 32 %, and 14 %, respectively. Treatment with vupanorsen also resulted in 55 % reduction in adipose tissue insulin resistance index, while other insulin sensitivity indices and HbA1c levels were not changed. Additional investigations into HFF and DEXA parameters suggested dynamic changes in fat partitioning during treatment. Adverse events observed were related to common serious complications associated with diabetes and FPLD. Vupanorsen was well tolerated, and there was no effect on platelet count. Conclusions Although limited, these results suggest that targeting ANGPTL3 with vupanorsen could address several metabolic abnormalities in patients with FPLD.

OBJECTIVE Angiopoietins (Angs) regulate endothelial permeability. Ang-1 and 2 (Ang-1 and Ang-2) are implied in endothelial stability through an antagonism effect. The objectives of the present study were to describe and compare changes in Ang levels after transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR). DESIGN A prospective, single-center study. PARTICIPANTS Adult patients with aortic stenosis scheduled for SAVR or TAVR. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Ang-1 and Ang-2 were measured using an enzyme-linked immunosorbent assay right before surgery (T0), at the end of surgery (T1), and at day one (T2). Sixty consecutive patients (SAVR group [n = 30] and TAVR group [n = 30]) were included between January and June 2017. Ang-1 decreased significantly after both TAVR (T0: 3,663 [2,602-4,262]; T1: 1,611 [981-2,409]; T2: 1,082 [652-1,589] ng/mL; p < 0.0001) and SAVR (T0: 1,603 [975-2,849]; T1: 783 [547-1,024]; T2: 828 [460-1,227] ng/mL; p = 0.0001). Ang-2 increased significantly after SAVR (T0: 2,472 [1,502-3,622]; T1: 2,997 [1,759-3,839]; T2: 5,421 [3,557-7,087] ng/mL; p < 0.0001) but did not change markedly after TAVR (T0: 3,343 [2,661-6,272]; T1: 3,788 [2,574-5,016]; T2: 3,446 [3,029-6,313] ng/mL; p = 0.066). Among patients with paravalvular leakage, the changes in the plasma Ang-2 level and the Ang-2/Ang-1 ratio were greater. CONCLUSION SAVR induces greater alterations of Ang homeostasis than TAVR, confirming a role for the use of cardiopulmonary bypass. Paravalvular leakage after TAVR is associated with Ang changes similar to those observed with SAVR.

Human basophils, first identified over 140 years ago, account for just 0.5-1% of circulating leukocytes. While this scarcity long hampered basophil studies, innovations during the past 30 years, beginning with their isolation and more recently in the development of mouse models, have markedly advanced our understanding of these cells. Although dissimilarities between human and mouse basophils persist, the overall findings highlight the growing importance of these cells in health and disease. Indeed, studies continue to support basophils as key participants in IgE-mediated reactions, where they infiltrate inflammatory lesions, release pro-inflammatory mediators (histamine, leukotriene C4: LTC4) and regulatory cytokines (IL-4, IL-13) central to the pathogenesis of allergic diseases. Studies now report basophils infiltrating various human cancers where they play diverse roles, either promoting or hampering tumorigenesis. Likewise, this activity bears remarkable similarity to the mounting evidence that basophils facilitate wound healing. In fact, both activities appear linked to the capacity of basophils to secrete IL-4/IL-13, with these cytokines polarizing macrophages toward the M2 phenotype. Basophils also secrete several angiogenic factors (vascular endothelial growth factor: VEGF-A, amphiregulin) consistent with these activities. In this review, we feature these newfound properties with the goal of unraveling the increasing importance of basophils in these diverse pathobiological processes.

Anti-angiogenic approaches have significantly advanced the treatment of vascular-related pathologies. The ephemeral outcome and known side effects of the current vascular endothelial growth factor (VEGF)-based anti-angiogenic treatments have intensified research on other growth factors. The angiopoietin/Tie (Ang/Tie) family has an established role in vascular physiology and regulates angiogenesis, vascular permeability, and inflammatory responses. The Ang/Tie family consists of angiopoietins 1-4, their receptors, tie1 and 2 and the vascular endothelial-protein tyrosine phosphatase (VE-PTP). Modulation of Tie2 activation has provided a promising outcome in preclinical models and has led to clinical trials of Ang/Tie-targeting drug candidates for retinal disorders. Although less is known about the role of Ang/Tie in pulmonary disorders, several studies have revealed great potential of the Ang/Tie family members as drug targets for pulmonary vascular disorders as well. In this review, we summarize the functions of the Ang/Tie pathway in retinal and pulmonary vascular physiology and relevant disorders and highlight promising drug candidates targeting this pathway currently being or expected to be under clinical evaluation for retinal and pulmonary vascular disorders.

BACKGROUND: Evidence shows that activation of pulmonary vascular endothelium and neutrophils are involved in the pathophysiology of acute bronchiolitis. We hypothesized that levels of markers of endothelial activation and leukocyte counts are associated with requirement and duration of respiratory support.METHODS: Thirty-four infants with bronchiolitis and eight controls were included. Nasopharyngeal swabs and blood samples were taken at admission. Serum levels of Angiopoietin (Ang)-1, Ang-2, sP-selectin, sE-selectin, vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1), and leukocyte counts were measured. For univariate analysis, bronchiolitis cases were grouped into two groups, namely those not requiring and those requiring any form of respiratory support. To control for known risk factors for poor outcome (i.e., age, prematurity, and congenital heart disease), and for days post symptom onset, linear regression analysis was performed with duration of any type of respiratory support in days.RESULTS: Ang-2 levels, Ang-2/Ang-1 ratios, sE-selectin levels, immature neutrophil count, and neutrophil/lymphocyte ratio (NLR) were higher in acute bronchiolitis versus controls. Ang-2, and NLR levels were significantly higher, and lymphocyte counts significantly lower, in infants that required respiratory support versus those that did not. Ang-2 levels (β: .32, 95% confidence interval [CI]: 0.19-1.19) and NLR (β: .68, 95% CI: 0.17-1.19) were positive predictors for the duration of respiratory support.CONCLUSIONS: Markers of endothelial and neutrophil activation are associated with respiratory support for acute bronchiolitis. Admission Ang-2 levels and NLR may be promising markers to determine requirement of respiratory support and deserve further study.

Aziza Alrafiah,1 Ebtisam Alofi,2 Yasser Almohaya,1 Abdullah Hamami,1 Talal Qadah,1 Safa Almaghrabi,2 Nora Hakami,1 Moafaq S Alrawaili,3 Haythum O Tayeb3 1Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia; 2Department of Physiology, Medical School, King Abdulaziz University, Jeddah, Saudi Arabia; 3Division of Neurology, Department of Internal Medicine, Faculty of Medicine, King AbdulAziz University, Jeddah, Saudi ArabiaCorrespondence: Aziza Alrafiah Tel +966 0126401000 Ext. 23495Email aalrafiah@kau.edu.saIntroduction: Stroke is a global health issue, and ischemic stroke is among the most common strokes affecting many people worldwide. Throughout ischemic stroke, various immune cells counter its effect by releasing cytokines, chemokines, and angiogenic molecules. These molecules can work as potential biomarkers in the diagnosis and monitoring of the progress of ischemic stroke. The current study investigated the use of angiogenic molecules as biomarkers in ischemic stroke patients.Methods: The samples were obtained from twenty healthy subjects and nineteen patients with ischemic stroke. Multiplex assay was used to measure the serum levels of angiogenic biomarkers, including endoglin, VEGF-A, endothelin-1, G-CSF, and angiopoietin-2. All data were analyzed using an unpaired Student’s t-test. Correlations between measured parameters were made using Pearson correlations.Results: Angiopoietin-2, VEGF-A, endothelin-1, and endoglin levels in stroke patients were significantly higher compared to healthy controls. Nevertheless, G-CSF level showed a non-significant increase in patients compared to controls. The correlation coefficient of measured angiogenic biomarkers among patients showed significant correlations between endoglin, angiopoietin, VEGF-A, and endothelin-1.Discussion: The angiogenic factors were significantly increased in patients with ischemic stroke, which may help in the early detection of ischemic stroke and consequently prompt treatment and better prognosis.Keywords: stroke, angiopoietin biomarkers, angiopoietin, endoglin, endothelin-1, VEGF-A

Acute kidney injury (AKI) is a frequent and potentially fatal complication of snakebites. In the setting of snakebites, endothelial biomarkers may be used to predict disease severity and can play a major role in AKI pathophysiology. The aim of this study was to investigate the potential role of endothelial biomarkers in predicting AKI in Bothrops envenoming. Therefore, blood and urine samples were collected from 26 patients admitted to the emergency department after Bothrops envenoming at 3 different post-bite points in time: on admission (up to 8 h post-bite), 12–16 h, and 24–28 h post-bite, to investigate the time course of endothelial biomarkers in AKI following Bothrops snakebites. The diagnostic performance of injury biomarkers in Bothrops envenomation was evaluated. AKI was diagnosed using the Kidney Disease Improving Global Outcomes (KDIGO) criteria. There was an association between endothelial injury and increased risk for AKI in bothropic envenoming. Angiopoietin- 1 (Ang-1) and Vascular cell adhesion protein-1 (VCAM-1) were useful biomarkers to predict mild AKI [AUC-ROC: Ang-1 0.82, VCAM-1 0.76] within the interval of 8–16 h post Bothrops snakebites. The use of endothelial biomarkers VCAM-1 e Ang-1 within 12−16 h post-bite may be useful in the early stage of mild AKI related to Bothrops envenoming and might have an effect on the early intervention for renal protection in less severe Bothrops-related AKI.

Several biomarkers for detecting pulmonary hypertension (PH) have been reported. However, these biomarkers are deemed insufficient to detect PH in its early stages. We evaluated the utility of serum angiopoietin (ANGP), a glycoprotein related to angiogenesis, as a diagnostic and prognostic biomarker of PH. Patients with PH who underwent right-heart catheterization, were retrospectively studied. Serum concentrations of ANGP-1 and ANGP-2 were measured using an enzyme-linked immunosorbent assay in patients with PH (n = 32), those with idiopathic pulmonary fibrosis (IPF) without PH (as a disease control, n = 75), and age-matched healthy controls (HC, n = 60). Nineteen patients (59.4%) with PH had World Health Organization group 3 PH. Serum ANGP-2 concentration, but not ANGP-1, in patients with PH was significantly higher compared with that in HC (p = 0.025) and in patients with IPF without PH (p = 0.008). Serum ANGP-2 concentration in patients with PH positively and significantly correlated with N-terminal pro-B-type natriuretic peptide (r = 0.769, p

Background Mucopolysaccharide polysulfate (MPS) is a heparinoid and MPS-containing formulations are widely used as moisturizers for dry skin and to treat peripheral vascular insufficiency. Although MPS has therapeutic effects in skin diseases with microvascular abnormalities, the effects of MPS on microvascular function remain incompletely understood. Objective The aim of this study was to evaluate the functional activities of MPS on human pericytes (HPC) and human dermal microvascular endothelial cells (HDMEC) in vitro, and on microvascular permeability of the skin. Methods The protein expression of angiopoietin (Ang)-1 in HPC, and platelet-derived growth factor-BB (PDGF-BB) and phosphorylated tyrosine-protein kinase receptor 2 (Tie2) in HDMEC were measured in the presence or absence of MPS. The vascular barrier was evaluated by the expressions of claudin-5 and vascular endothelial (VE)-cadherin, and transendothelial electrical resistance (TEER). Results In HPC, MPS dose-dependently enhanced Ang-1 secretion, which activated Tie2 in HDMEC. In HDMEC, MPS significantly increased the production of PDGF-BB, which is important for the recruitment of HPC to the vascular endothelium, and significantly increased the phosphorylation of Tie2, which results in the activation of the Ang-1/Tie2 signaling . MPS significantly increased the expression of tight junction protein claudin-5 and TEER in the HDMEC. Moreover, the intradermal injection of MPS prevented vascular endothelial growth factor-induced increase in vascular permeability in mouse skin. Conclusion We found that MPS promoted microvascular stabilization and barrier integrity in HDMEC via Ang-1/Tie2 activation. These results suggest that MPS might improve microvascular abnormalities in various diseases accompanied by disturbances in Ang-1/Tie2 signaling.

Purpose:The immune environment represents a new, but little explored, tool for understanding neuroendocrine neoplasms (NENs) behavior. An immunosuppressed microenvironment is hypothesized to promote NENs progression. A missing profiling of circulating leukocyte and peripheral blood mononuclear cell (PBMC) subpopulations would open new perspectives in the still limited diagnostic-therapeutic management of NENs.Methods: A cross-sectional case-control pilot study was performed recruiting 30 consecutive patients: 15 naïve to treatment, with histologically proven gastroenteropancreatic (GEP) neuroendocrine tumors (NETs) and 15 healthy controls (Ctrl), matched for age and sex. PBMC subpopulations were studied by flow cytometry. Soluble Tie2 (sTie2), Angiopoietin-1 (Ang-1), Angiopoietin-2 (Ang-2) were evaluated by ELISA.Results: Immune cell profiling revealed a significant lower CD3-CD56+ natural killer (NK) cell count in NETsversusCtrl (p=0.04). NK subset analysis showed a reduced relative count of CD56+CD16+ NK cells (p=0.002) in NETsversusCtrl. Patients with NET showed a higher percentage of CD14+CD16++non-classical monocytes (p=0.01), and a lower percentage of CD14+CD16+intermediate monocytes (p=0.04). A decrease in percentage (p=0.004) of CD4+ T-helper lymphocytes was found in NETs patients. Evaluation of cellular and serum angiopoietin pathway mediators revealed in NET patients a higher relative count of TEM (p), and high levels of Ang-1 (p=0.003) and Ang-2 (p=0.002).Conclusions: patients with GEP-NETs presented an immunosuppressed environment characterized by a low count of cytotoxic NK cells, a high count of anti-inflammatory non-classical monocytes, and a low count of T-helper lymphocytes. Higher levels of TEM and angiopoietins suggest a crosstalk between innate immunity and angiogenic pathways in NETs.

Background Sepsis in premature newborns is a risk factor for bronchopulmonary dysplasia (BPD), but underlying mechanisms of lung injury remain unclear. Aberrant expression of endothelial cell (EC) angiopoietin 2 (ANGPT2) disrupts angiopoietin 1 (ANGPT1)/TIE2-mediated endothelial quiescence, and is implicated in sepsis-induced acute respiratory distress syndrome in adults. We hypothesized that recombinant ANGPT1 will mitigate sepsis-induced ANGPT2 expression, inflammation, acute lung injury (ALI), and alveolar remodeling in the saccular lung. Methods Effects of recombinant ANGPT1 on lipopolysaccharide (LPS)-induced endothelial inflammation were evaluated in human pulmonary microvascular endothelial cells (HPMEC). ALI and long-term alveolar remodeling were assessed in newborn mice exposed to intraperitoneal LPS and recombinant ANGPT1 pretreatment. Results LPS dephosphorylated EC TIE2 in association with increased ANGPT2 in vivo and in vitro. ANGPT1 suppressed LPS and ANGPT2-induced EC inflammation in HPMEC. Neonatal mice treated with LPS had increased lung cytokine expression, neutrophilic influx, and cellular apoptosis. ANGPT1 pre-treatment suppressed LPS-induced lung Toll-like receptor signaling, inflammation, and ALI. LPS-induced acute increases in metalloproteinase 9 expression and elastic fiber breaks, as well as a long-term decrease in radial alveolar counts, were mitigated by ANGPT1. Conclusions In an experimental model of sepsis-induced BPD, ANGPT1 preserved endothelial quiescence, inhibited ALI, and suppressed alveolar simplification. Impact Key message: Angiopoietin 1 inhibits LPS-induced neonatal lung injury and alveolar remodeling. Additions to existing literature: Demonstrates dysregulation of angiopoietin-TIE2 axis is important for sepsis- induced acute lung injury and alveolar simplification in experimental BPD. Establishes recombinant Angiopoietin 1 as an anti-inflammatory therapy in BPD. Impact Angiopoietin 1-based interventions may represent novel therapies for mitigating sepsis-induced lung injury and BPD in premature infants.

Objectives: to assess the possible association between Angiopoietin-2 (ANGT-2) and the risk of recurrent implantation failure and to determine the possible role of it in the successfulness of in vitro fertilization process. Methods: A case control study was done on 80 female patients with Recurrent Implantation Failure (RIF) and 23 female patients with successful in-vitro fertilization (IVF) who were recruited from the Department of Obstetrics and Gynecology at Al Imamain Al-Kadhimain Medical City, Baghdad, Iraq between January and September 2019. The levels of ANGT-2 were measured in the serum of women with RIF and successful IVF and compared with those with a positive IVF and control group that comprise 74 age, BMI and sex-matched apparently healthy females. Results: The data revealed that there was a significant (p=0.007) decrease in ANGPT2 levels (2914.66±834.08) in women with recurrent implantation failure (RIF) in a comparison with controls (3235.83 ±444.16) whereas non-significant (p>0.05) differences were obtained between women with a successful in vitro fertilization (+ve IVF) and controls and also with RIF group. Conclusions: the possible association between ANGT-2 and the risk of RIF and the possibility of using it as a marker for a prognosis in women subjected to IVF process

The aim of this study was to determine early weight loss-associated changes in subcutaneous abdominal white adipose tissue (WAT) gene expression in obese men with lowered serum testosterone by RNA next-generation sequencing. Fourteen men, mean age (IQR) 51.6 years (43.4–54.5), BMI 38.3 kg/m2 (34.6–40.8) and total testosterone 8.4 nmol/L (7.5–9.5) provided subcutaneous WAT samples at baseline and after 2 weeks of a very low energy diet. Body weight loss was similar in participants receiving testosterone (n = 6), −5.27 kg [95% CI −6.17; −4.26], and placebo (n = 8), −4.57 kg [95% CI −6.10; −3.55], p = 0.86. In placebo-treated men, of the 14,410 genes expressed in subcutaneous WAT, four genes, Angiopoietin-like 4, Semaphorin 3 G, Neuropilin 2 and Angiopoietin 4, were upregulated (adjusted false discovery rate P

BACKGROUND AND AIMS: Cardiac and vascular growth factors (GF) may influence myocardial remodeling through cardiac growth and angiogenic effects. We hypothesized that concentrations of circulating GF are associated with cardiac remodeling traits. METHODS: We related blood concentrations of vascular endothelial GF (VEGF), VEGFR-1 (sFlt1), angiopoietin 2 (Ang-2), soluble angiopoietin type-2 receptor (sTie2), hepatocyte GF (HGF), insulin-like GF (IGF)-1, IGF binding protein (IGFBP)-3, and growth differentiation factor-15 (GDF-15) to echocardiographic traits in 3151 Framingham Study participants (mean age 40 years, 55% women). We evaluated the following measures: left ventricular (LV) mass index (LVMi), LV ejection fraction (LVEF), global longitudinal strain (GLS), mitral E/e’, and aortic root diameter (AoR). All biomarker values were sex-standardized. RESULTS: In multivariable-adjusted analyses, higher GDF-15 concentrations were associated with higher log-LVMi (β=0.009 per SD, P =0.01). Similarly, sTie2 concentrations were positively associated with log-E/e’ (β=0.011 per SD, P =0.04). IGF-1 and Ang-2 concentrations were positively and negatively associated with GLS, respectively (β(IGF-1) =0.16 per SD and β(Ang-2) =−0.15 per SD, both P

Objective This study investigated changes of plasma cytokines and aimed to build a dynamic nomogram for diabetic macular edema (DME) in type 2 diabetes mellitus (T2DM). Methods In a pilot cohort, plasma samples were selected from 9 T2DM patients and 9 DME patients to screen for cytokine differences. The screening cytokines were then validated by enzyme-linked immunoassay in a cohort, which contained 100 DME (DME group) and 100 T2DM patients without DME (T2DM group). A dynamic nomogram for predicting DME was developed, based on the plasma cytokines. Results In the pilot cohort, 11 plasma cytokines were significantly increased in the DME group. In the validation cohort, platelet-derived growth factor (PDGF)-BB, tissue inhibitors of metalloproteinase (TIMP)-1, angiopoietin (ANG-1), and vascular endothelial cell growth factor receptor (VEGFR)-2 were confirmed to be significantly elevated in the DME group. The dynamic nomogram demonstrated good calibration and discrimination, with an area under the receiver operating characteristic curve (AUC) of 0.88. In the test set, sensitivity, specificity, and AUC were 73.3%, 80.0%, and 0.84, respectively. Conclusion Plasma cytokines were closely associated with DME. A novel dynamic monogram including ANG-1, PDGF-BB, TIMP-1, and VEGFR2 was a novel tool for predicting DME.

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Background Autologous fat grafting is often a crucial aspect of reconstructive and aesthetic surgeries, yet poor graft retention is a major issue with this technique. Enriching fat grafts with adipose tissue-derived mesenchymal stem cells (AD-MSCs) improves graft survival—however, AD-MSCs represent a heterogeneous population. Selection of subpopulations of AD-MSCs would allow the targeting of specific AD-MSCs that may benefit fat graft survival more than the general AD-MSC population. Methods Human AD-MSCs were selected for the surface marker CD271 using magnetic-activated cell sorting and compared to the CD271 negative phenotype. These subpopulations were analysed for gene expression using Real-Time qPCR and RNA sequencing; surface marker characteristics using immunostaining; ability to form tubules when cultured with endothelial cells; and gene and protein expression of key angiogenic mediators when cultured with ex-vivo adipose tissue. Results Human AD-MSCs with the surface marker CD271 express angiogenic genes at higher levels, and inflammatory genes at lower levels, than the CD271− AD-MSC population. A greater proportion of CD271+ AD-MSCs also possess the typical complement of stem cell surface markers and are more likely to promote effective neoangiogenesis, compared to CD271− AD-MSCs. Conclusion Enriching grafts with the CD271+ AD-MSC subpopulation holds potential for the improvement of reconstructive and aesthetic surgeries involving adipose tissue.

Visual Abstract, Highlights • Children with a bidirectional superior cavopulmonary connection (Glenn circulation) develop dysregulated angiogenesis and pulmonary angiodysplasia in the form of arteriovenous malformations (AVMs). No targeted therapy exists. • The von Willebrand factor (vWF)–angiopoietin axis plays a major role in normal angiogenesis, angiodysplasia, and AVM formation in multiple diseases. • vWF and angiopoietin-2 (which destabilizes vessel formation) were abnormal in children with a Glenn circulation versus control children. Within Glenn patients, angiopoietin-1 (which stabilizes vessel formation) and angiogenesis were different in the systemic versus pulmonary circulation. Plasma angiopoietin-1 was lower in the pulmonary circulation of Glenn patients with pulmonary AVMs than Glenn patients without AVMs. • In parallel, differences in multiple angiogenic and inflammatory signaling peptides were observed between Glenn patients and controls, which indicated derangements in multiple angiogenic pathways in Glenn patients. • These findings support the novel hypothesis that abnormal vWF metabolism and angiopoietin signaling dysregulate angiogenesis and contribute to pulmonary AVM formation in children with a Glenn circulation. • The vWF-angiopoietin axis may be a target to correct angiogenic imbalance and reduce pulmonary angiodysplasia in Glenn patients., Summary Children with a bidirectional superior cavopulmonary (Glenn) circulation develop angiodysplasia and pulmonary arteriovenous malformations (AVMs). The von Willebrand factor (vWF)–angiopoietin axis plays a major role in AVM formation in multiple diseases. We observed derangements in global angiogenic signaling, vWF metabolism, angiopoietins, and in vitro angiogenesis in children with a Glenn circulation versus controls and within Glenn pulmonary versus systemic circulations. These findings support the novel hypothesis that abnormalities in the vWF-angiopoietin axis may dysregulate angiogenesis and contribute to Glenn pulmonary AVMs. The vWF-angiopoietin axis may be a target to correct angiogenic imbalance in Glenn patients, for whom no targeted therapy exists.

Objective The purpose of the present study is to investigate whether angiopoietin-like 4 (ANGPTL4) can promote angiogenesis and neurogenesis following stroke, as well as to explore the potential underlying mechanisms. Methods ANGPTL4 (40 μg/kg) or a vehicle was administered via tail vein beginning 5 min prior to electrocoagulation-induced stroke in male C57/B6 J mice. Infarct volume was measured via Nissl staining at day 3 post-stroke. Angiogenesis, neurogenesis and activation of microglia were evaluated by immunofluorescence co-labelling bromodeoxyuridine (BrdU) with von Willebrand factor (vWF), doublecortin (DCX), neuronal nuclei (NeuN) and Iba1 at day 7 post-stroke. The levels of p-AKT, T-AKT, VEGF, MPO, Fas and FasL in the ipsilesional brain were detected by Western blot analysis at day 1 post-stroke. Results Compared with the Vehicle group, ANGPTL4 reduced infarct volume significantly at day 3 post-stroke. ANGPTL4 significantly increased the number of BrdU+, BrdU+/vWF+and BrdU+/DCX+ cells in the peri-infarct zone, subventricular zone and subgranular zone and inhibited BrdU+/Iba1+ cells in the peri-infarct zone at day 7 post-stroke. The level of p-AKT and the ratio of phospho-AKT to total-AKT in the ipsilesional brain were significantly elevated, the levels of MPO, Fas and FasL were significantly declined; however, there was no significant difference at day 1 post-stroke between the VEGF and total-AKT levels in both groups. Conclusions ANGPTL4 enhances angiogenesis and neurogenesis post-stroke by upregulating the phosphorylation of AKT, reduces neuronal death and inhibits inflammatory response, which resultes from the inhibition of FasL/Fas expression and its downstream pathway.

Background As a tissue-specific proangiogenic or antiangiogenic agent, angiopoietin-like 4 (ANGPTL4) has recently gained attention in many diseases, such as metabolic syndrome, cardiovascular disease and cancer. However, the roles of ANGPTL4 in angiogenesis and tumor growth in epithelial ovarian cancer, the most lethal gynecologic malignancy, remain unclear. Objective To identify a novel mechanism of ANGPTL4 inhibition in epithelial ovarian cancer. Methods Western blot, quantitative reverse transcription PCR, and immunofluorescence analyses were applied to evaluate ANGPTL4 expression in ovarian cancer cell lines. Cell proliferation, migration, and invasion were investigated through 5-ethynyl-2′-deoxyuridine (EdU) incorporation, CCK-8 and Transwell assays. The expression of epithelial-mesenchymal transition (EMT)-related proteins in ovarian cancer cells and tumor-bearing mice was evaluated. CD31 staining was used to identify tumor angiogenesis. Immunoprecipitation was performed to examine the regulatory relationship between ANGPTL4 and the vascular endothelial growth factor receptor 2 (VEGFR2)/vascular endothelial (VE)-cadherin/Src complex. VEGFR2 phosphorylation at Y949 and VE-cadherin expression were assessed by western blotting. Inactivation of VEGFR2 Y949 phosphorylation was achieved in a MISIIR-TAg VEGFR2Y949F/Y949F mouse model. Results Here, we demonstrated that ANGPTL4 was overexpressed in A2780 and CAOV3 ovarian cancer cells. In vitro assays indicated that inhibition of ANGPTL4 by lentiviral small interfering RNA does not alter ovarian cancer cell proliferation, migration, invasion, and EMT, while ANGPTL4 silencing exhibited significant inhibitory effects on tumor angiogenesis, growth, and metastasis in vivo. Immunoprecipitation analysis showed that suppression of ANGPTL4 was accompanied by dissociation of the VEGFR2/VE-cadherin/Src complex and phosphorylation of VEGFR2 Y949 in A2780 and CAOV3 ovarian tumors. Inactivation of VEGFR2 Y949 phosphorylation in MISIIR-TAg VEGFR2Y949F/Y949F mice abolished all tumor-suppressive effects of ANGPTL4 inhibition in spontaneous ovarian carcinoma. Conclusions Overall, our results indicate that ANGPLT4 silencing delays tumor progression in specific types of ovarian cancer and may be a potential target for individualized treatment of ovarian cancer.

The angopoietin/tyrosine kinase with immunoglobulin and epidermal growth factor homology domains (Ang/Tie) pathway is an emerging key regulator in vascular development and maintenance. Its relevance to clinicians and basic scientists as a potential therapeutic target in retinal and choroidal vascular diseases is highlighted by recent preclinical and clinical evidence. The Ang/Tie pathway plays an important role in the regulation of vascular stability, in angiogenesis under physiological and pathological conditions, as well as in inflammation. Under physiological conditions, angiopoietin-1 (Ang-1) binds to and phosphorylates the Tie2 receptor, leading to downstream signalling that promotes cell survival and vascular stability. Angiopoietin-2 (Ang-2) is upregulated under pathological conditions and acts as a context-dependent agonist/antagonist of the Ang-1/Tie2 axis, causing vascular destabilisation and sensitising blood vessels to the effects of vascular endothelial growth factor-A (VEGF-A). Ang-2 and VEGF-A synergistically drive vascular leakage, neovascularisation and inflammation, key components of retinal vascular diseases. Preclinical evidence suggests that modulating the Ang/Tie pathway restores vascular stabilisation and reduces inflammation. This review discusses how targeting the Ang/Tie pathway or applying Ang-2/VEGF-A combination therapy may be a valuable therapeutic strategy for restoring vascular stability and reducing inflammation in the treatment of retinal and choroidal vascular diseases.摘要: 本篇文章是关于不同照明条件对原发性开角型青光眼 (POAG) 患者视力和生活质量影响的研究的系统回顾。研究对CINAHL, MEDLINE, PsycARTICLES, PsycINFO, Embase and Ovid Nursing Database六个数据库进行系统文献检索, 截止发表日期为2019年4月。检索内容包括诊断为POAG的患者, 在变换照明设备/光照水平或炫光的情况下评估人群的视功能和生活质量。两名研究者独立筛选符合标准的受试者。从实验设计, 入选者标准, 结果与结论中挑选合格的研究并提取数据。入选研究的质量经过了严格的评估。在8437项研究中, 共有56项研究符合入选标准。在POAG患者中调查光照对以下因素的影响: 生活质量 (18/56),心理物理学干预 (16/56), 功能性视力 (10/56), 日常活动 (10/56) 和定性发现 (2/56)。POAG会影响患者的低亮度对比敏感度, 炫光症状, 暗适应的时间和程度。在视觉生活质量调查问卷中, 根据POAG患者反馈, 照明设备, 炫光和暗适应的问题较其它问题更多见。这些问题随着进行性视野的缺失而严重, 与同年龄对照组相比(AMC), POAG患者在发病的早期在低亮度和不同亮度切换的环境中会面临更多的困难, 这对之前POAG患者早期阶段没有症状的认知进行了挑战。但是, 基于性能方面的研究很少显示POAG参与者和AMC在模拟非最佳照明条件下日常活动方面有显着差异。 需要对较大的样本进行进一步研究, 以优化环境照明和面向任务的照明, 以支持患者适应POAG。未来亟待大样本的研究为POAG患者提供优化环境和适合工作的照明。.

Recent clinical and preclinical advances have highlighted the existence of a previously hypothesized lymphogenous route of metastasis. However, due to a lack of suitable preclinical modeling tools, its contribution to long-term disease outcome and relevance for therapy remain controversial. Here, we established a genetically engineered mouse model (GEMM) fragment–based tumor model uniquely sustaining a functional network of intratumoral lymphatics that facilitates seeding of fatal peripheral metastases. Multiregimen survival studies and correlative patient data identified primary tumor–derived Angiopoietin-2 (Ang2) as a potent therapeutic target to restrict lymphogenous tumor cell dissemination. Mechanistically, tumor-associated lymphatic endothelial cells (EC), in contrast to blood vascular EC, were found to be critically addicted to the Angiopoietin–Tie pathway. Genetic manipulation experiments in combination with single-cell mapping revealed agonistically acting Ang2–Tie2 signaling as key regulator of lymphatic maintenance. Correspondingly, acute presurgical Ang2 neutralization was sufficient to prolong survival by regressing established intratumoral lymphatics, hence identifying a therapeutic regimen that warrants further clinical evaluation. Significance: Exploiting multiple mouse tumor models including a unique GEMM-derived allograft system in combination with preclinical therapy designs closely matching the human situation, this study provides fundamental insight into the biology of tumor-associated lymphatic EC and defines an innovative presurgical therapeutic window of migrastatic Ang2 neutralization to restrict lymphogenous metastasis. This article is highlighted in the In This Issue feature, p. 211

Vascular diseases are the main reason for morbidity and mortality worldwide. As we know, the earlier phase of vascular diseases is endothelial dysfunction in humans, the endothelial tissues play an important role in inflammation, coagulation, and angiogenesis, via organizing ligand-receptor associations and the various mediators’ secretion. We can use many inflammatory non-invasive tests (flowmediated dilatation, epicedial fat thickness, carotid-intima media thickness, arterial stiffness and anklebrachial index) for assessing the endothelial function. In addition, many biomarkers (ischemia modified albumin, pentraxin-3, E-selectin, angiopoietin, endothelial cell specific molecule 1, asymmetrical dimethylarginine, von Willebrand factor, endothelial microparticles and endothelial progenitor cells) can be used to evaluate endothelial dysfunction. We have focused on the relationship between endothelial dysfunction and inflammatory markers of vascular disease in this review.

Excessive tumour growth results in a hypoxic environment around cancer cells, thus inducing tumour angiogenesis, which refers to the generation of new blood vessels from pre-existing vessels. This mechanism is biologically and physically complex, with various mathematical simulation models proposing to reproduce its formation. However, although temporary vessel regression is clinically known, few models succeed in reproducing this phenomenon. Here, we developed a three-dimensional simulation model encompassing both angiogenesis and tumour growth, specifically including angiopoietin. Angiopoietin regulates both adhesion and migration between vascular endothelial cells and wall cells, thus inhibiting the cell-to-cell adhesion required for angiogenesis initiation. Simulation results showed a regression, i.e. transient decrease, in the overall length of new vessels during vascular network formation. Using our model, we also evaluated the efficacy of administering the drug bevacizumab. The results highlighted differences in treatment efficacy: (1) earlier administration showed higher efficacy in inhibiting tumour growth, and (2) efficacy depended on the treatment interval even with the administration of the same dose. After thorough validation in the future, these results will contribute to the design of angiogenesis treatment protocols.

PURPOSE To provide a concise overview for ophthalmologists and practicing retina specialists of available clinical evidence of manipulating the angiopoietin/tyrosine kinase with immunoglobulin-like and endothelial growth factor-like domains (Tie) pathway and its potential as a therapeutic target in retinal vascular diseases. METHODS A literature search for articles on the angiopoietin/Tie pathway and molecules targeting this pathway that have reached Phase 2 or 3 trials was undertaken on PubMed, Association for Research in Vision and Ophthalmology meeting abstracts (2014-2019), and ClinicalTrials.gov databases. Additional information on identified pipeline drugs was obtained from publicly available information on company websites. RESULTS The PubMed and Association for Research in Vision and Ophthalmology meeting abstract search yielded 462 results, of which 251 publications not relevant to the scope of the review were excluded. Of the 141 trials related to the angiopoietin/Tie pathway on ClinicalTrials.gov, seven trials focusing on diseases covered in this review were selected. Vision/anatomic outcomes from key clinical trials on molecules targeting the angiopoietin/Tie pathway in patients with retinal vascular diseases are discussed. CONCLUSION Initial clinical evidence suggests a potential benefit of targeting the angiopoietin/Tie pathway and vascular endothelial growth factor-A over anti-vascular endothelial growth factor-A monotherapy alone, in part due to of the synergistic nature of the pathways.

Background and Objectives: Faricimab is a novel bispecific antibody with Fab regions inhibiting both vascular endothelial growth factor-A and angiopoietin-2. Therefore, this study aimed to obtain short-term outcomes of intravitreal injection of faricimab (IVF) for the treatment of diabetic macular edema (DME) in daily clinical practice. Materials and Methods: A retrospective review was carried out on consecutive patients with DME who had been treated with IVF and were followed up for at least 1 month. Outcome measures included changes in logMAR best-corrected visual acuity (logMAR BCVA), central retinal thickness (CRT), number of IVF administrations, and safety. Clinical outcomes were also compared between the treatment-naïve and switch groups. Results: A total of 21 consecutive DME eyes from 19 patients were identified. The mean number of IVFs was 1.6 ± 0.8 during the mean follow-up time of 5.5 months. The overall mean logMAR BCVA following IVF was 0.236, 0.204, 0.190, and 0.224 at baseline, 1, 3, and 6 months, respectively, without a significant change from baseline to 1 month (p = 0.176) or for 6 months (p = 0.923). The overall mean CRT (μm) following IVF was 400.6, 346.6, 342.1, and 327.5 at baseline, 1, 3, and 6 months, respectively. CRT significantly decreased from baseline to 1 month (p = 0.001) but did not reach a significant level over 6 months following IVF (p = 0.070). No significant difference in BCVA or CRT was observed between the treatment-naïve and switch groups. No serious safety concerns were noted. Conclusions: IVF for the treatment of DME may preserve visual acuity and improve macular thickness without serious safety concerns in the short term in a real-world clinical setting.

Angiopoietin-like 4 (ANGPTL4) is critical for regulating plasma lipids, and thus an attractive therapeutic target for cardiovascular diseases. Unfortunately, targeting ANGPTL4 results in a proinflammatory and ultimately lethal phenotype in animals. The serendipitous discovery of cardiac ANGPTL4 as a circadian protein reveals novel mechanistic insight and a solution for this therapeutic dilemma.

Chronic subdural hematoma (CSDH) is an angiogenic disease that is involved with many inflammatory mediators. Tie2 is predominantly expressed in the embryonic endothelium and plays an important role in the maturation and stabilization of the vasculature. Angiopoietin (Ang)1 and Ang2 are well-known ligands of the Tie2 receptor. We examined the expression of Ang1 and Ang2 in CSDH fluid and the expression of Tie-2 receptor and components of the angiogenic signaling pathways in the outer membrane of CSDH. Twenty-five samples of CSDH fluid and eight samples of outer membrane of CSDH were included. The concentrations of Ang1 and Ang2 in the CSDH fluid were measured using enzyme-linked immunosorbent assay (ELISA) kits. The expression of Tie2, phosphoinositide 3-kinase (PI3K), protein kinase B (Akt) mechanistic target of rapamycin (mTOR), GβL, 70 kDa ribosomal protein S6 kinase (p70S6K), eukaryotic initiation factor 4E (eIF-4E), and β-actin was examined by a Western blot analysis. The expression of Tie2, Akt, and mTOR was also examined by immunohistochemistry. The concentration of Ang2 in CSDH fluid was significantly higher than that in the serum or cerebrospinal fluid (CSF), and also higher than that of Ang1 in CSDH fluid. Tie2, PI3K, Akt, mTOR, GβL, p70S6K, and eIF-4E were detected in all cases. In addition, Tie2, Akt, and mTOR were localized in the endothelial cells of vessels in the CSDH outer membrane. Our data suggest that Ang2, although not Ang1, in CSDH fluid promotes angiogenesis in endothelial cells through the Tie2 receptor. The Ang2/Tie2 signaling pathway might therefore be a useful therapeutic target for treating the growth of intractable CSDH.

Angiopoietin-like 3 (ANGPTL3) is a 70kDa protein primarily expressed in the liver. The main physiological role is related to the inhibition of lipoprotein and endothelial lipases, thus affecting triglyceride hydrolysis. 1 The role of ANGPTL3 in atherosclerosis has emerged from genetics: carriers of loss of function (LOF) mutations of ANGPTL3, leading to low plasma levels, had a reduced risk of coronary artery disease and a lipid profile characterised by dramatic reductions of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol and triglycerides.2 However, although homozygous or compound heterozygous for ANGPTL3 LOF had a reduced capacity to promote cell cholesterol efflux, no clinical evidence of accelerated atherosclerosis was found.3 ANGPTL3 also influences the endothelial cell adhesion and stimulates the proliferation of haematopoietic stem cells,4 both potentially atherosclerosis associated. As, to date, in a general population no data have been reported on a possible direct involvement of ANGPTL3 with arterial disease, the present retrospective study was aimed to evaluate the relationship between ANGPTL3 plasma levels and extra-coronary arterial health, as assessed by the ankle–brachial blood pressure index (ABI), a validated, non-invasive tool for peripheral artery disease (PAD) screening.5 Moreover, levels of proprotein convertase subtilisn/kexin type 9 (PCSK9), which may play a crucial role in vascular aging, were also evaluated.6 The Brisighella Heart Study is a longitudinal population study on a randomly allocated sample representative of the entire population of Brisighella, a rural northern Italian village. The study, carried out in agreement with the Declaration of Helsinki, was approved by the institutional ethics board of the University Hospital of Bologna.

Background and aims: Statins suppress hepatic mRNA expression of ANGPTL3 encoding angiopoietin-like 3 in healthy subjects, but it is unknown if plasma ANGPTL3 concentrations are affected by statins prescribed to hypercholesterolemic patients in clinical practice. We therefore investigated the effect of statin treatment on plasma ANGPTL3 concentrations in hypercholesterolemic patients. In addition, we explored the underlying mechanism by which statins regulate ANGPTL3 in vitro. Methods: Plasma ANGPTL3 concentrations were measured in 93 genetically confirmed familial hypercholesterolemia (FH) patients who were using statin therapy and 61 statin naïve FH patients. Moreover, concentrations were measured in 14 hypercholesterolemic patients who discontinued their statin treatment for 4 weeks. In vitro studies were performed with Huh7 human hepatoma cells. Results: Plasma ANGPTL3 concentrations were 15% lower in statin treated FH patients compared to statin naïve FH patients (145 (120-193) vs. 167 (135-220) ng/ml, p = 0.012). Statin discontinuation resulted in a 21% (p

Immune-mediated angiogenesis is important in the pathogenesis of inflammatory bowel disease and targeted treatment could alleviate the disease. Thalidomide is an effective drug in inflammatory bowel disease, which might be related to its multiple role in anti-inflammatory, immunoregulatory, and anti-angiogenesis. This study is to investigate the effect of thalidomide on angiogenesis in tissues from patients and in vitro cells. Angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), VEGF, and CD31 expressions in intestinal mucosa from pediatric CD patients before and after thalidomide treatment were measured by immunohistochemistry. Western blotting and polymerase chain reaction were performed to characterize the change of angiogenic factors before and after treatment in remission. Human umbilical vein endothelial cells (HUVECs) treated by thalidomide were used to examine its effect on endothelial cell proliferation and migration and capillary-like structures. Results showed that VEGF and Ang-2 levels were significantly greater in CD patients over controls. Thalidomide produced a significant reduction in protein expression of Ang-2 and VEGF, along with a decrease in mRNA expression of Ang-2. While, Ang-1 level did not show a statistically significant change. Thalidomide significantly inhibited cell proliferation in a dose-dependent manner. It also suppressed VEGF- and Ang-2-induced cell migration and capillary-like tube formation in HUVECs. Therefore, our study suggests that VEGF and Ang-2 levels are up-regulated in pediatric CD patients. It also indicated that thalidomide can be able to deactivate endothelium by the downregulation effect on angiogenic factors by targeting VEGF and Ang-2.

BACKGROUND: In general, angiopoietin-2 levels are increased concomitantly with dengue clinical severity. AIM: This research aims to determine the role of mutation on angiopoietin-2 on dengue clinical severity. METHODS: A cross-sectional study of 108 children with dengue disease grouped by severity. Angiopoietin-2 level was examined by enzyme-linked immunosorbent assay. Polymerase chain reaction and double nucleic acid sequencing are using 2 Exon 4-F primers. RESULTS: Angiopoietin-2 levels on rs7834131 mutant are higher in dengue fever (p < 0.05) and dengue hemorrhage fever group than non-mutant, while on dengue shock syndrome, it is lower than non-mutant. CONCLUSION: Angiopoietin-2 mutation on rs7834131 might have a protective effect on dengue disease severity.

Vascular leak is a key driver of organ injury in diseases, and strategies that reduce enhanced permeability and vascular inflammation are promising therapeutic targets. Activation of the angiopoietin-1 (ANG1)-Tie2 tyrosine kinase signaling pathway is an important regulator of vascular quiescence. Here we describe the design and construction of a new soluble ANG1 mimetic that is a potent activator of endothelial Tie2 in vitro and in vivo. Using a chimeric fusion strategy, we replaced the extracellular matrix (ECM) binding and oligomerization domain of ANG1 with a heptameric scaffold derived from the C-terminus of serum complement protein C4-binding protein α. We refer to this new fusion protein biologic as Hepta-ANG1, which forms a stable heptamer and induces Tie2 phosphorylation in cultured cells, and in the lung following intravenous injection of mice. Injection of Hepta-ANG1 ameliorates vascular endothelial growth factor- and lipopolysaccharide-induced vascular leakage, in keeping with the known functions of Angpt1-Tie2 in maintaining quiescent vascular stability. The new Hepta-ANG1 fusion is easy to produce and displays remarkable stability with high multimericity that can potently activate Tie2. It could be a new candidate ANG1 mimetic therapy for treatments of inflammatory vascular leak, such as acute respiratory distress syndrome and sepsis.

Aberrant growth of blood vessels (neovascularization) is a key feature of severe eye diseases that can cause legal blindness, including neovascular age-related macular degeneration (nAMD) and diabetic retinopathy (DR). The development of anti-vascular endothelial growth factor (VEGF) agents has revolutionized the treatment of ocular neovascularization. Novel proangiogenic targets, such as angiopoietin and platelet-derived growth factor (PDGF), are under development for patients who respond poorly to anti-VEGF therapy and to reduce adverse effects from long-term VEGF inhibition. A rapidly advancing area is gene therapy, which may provide significant therapeutic benefits. Viral vector-mediated transgene delivery provides the potential for continuous production of antiangiogenic proteins, which would avoid the need for repeated anti-VEGF injections. Gene silencing with RNA interference to target ocular angiogenesis has been investigated in clinical trials. Proof-of-concept gene therapy studies using gene-editing tools such as CRISPR-Cas have already been shown to be effective in suppressing neovascularization in animal models, highlighting the therapeutic potential of the system for treatment of aberrant ocular angiogenesis. This review provides updates on the development of anti-VEGF agents and novel antiangiogenic targets. We also summarize current gene therapy strategies already in clinical trials and those with the latest approaches utilizing CRISPR-Cas gene editing against aberrant ocular neovascularization.

BackgroundOnset, development and progression of atherosclerosis are complex multistep processes. Many aspects of atherogenesis are not yet properly known. This study investigates the changes in vasculature that contribute to switching of vascular cells towards atherogenesis, focusing mainly on ageing.MethodsDatabases including PubMed, MEDLINE and Google Scholar were searched for published articles without any date restrictions, involving atherogenesis, vascular homeostasis, aging, gene expression, signaling pathways, angiogenesis, vascular development, vascular cell differentiation and maintenance, vascular stem cells, endothelial and vascular smooth muscle cells.ResultsAtherogenesis is a complex multistep process that unfolds in a sequence. It is caused by alterations in: epigenetics and genetics, signaling pathways, cell circuitry, genome stability, heterotypic interactions between multiple cell types and pathologic alterations in vascular microenvironment. Such alterations involve pathological changes in: Shh, Wnt, NOTCH signaling pathways, TGF beta, VEGF, FGF, IGF 1, HGF, AKT/PI3K/ mTOR pathways, EGF, FOXO, CREB, PTEN, several apoptotic pathways, ET – 1, NF-κB, TNF alpha, angiopoietin, EGFR, Bcl − 2, NGF, BDNF, neurotrophins, growth factors, several signaling proteins, MAPK, IFN, TFs, NOs, serum cholesterol, LDL, ephrin, its receptor pathway, HoxA5, Klf3, Klf4, BMPs, TGFs and others.This disruption in vascular homeostasis at cellular, genetic and epigenetic level is involved in switching of the vascular cells towards atherogenesis. All these factors working in pathologic manner, contribute to the development and progression of atherosclerosis.ConclusionThe development of atherosclerosis involves the switching of gene expression towards pro-atherogenic genes. This happens because of pathologic alterations in vascular homeostasis. When pathologic alterations in epigenetics, genetics, regulatory genes, microenvironment and vascular cell biology accumulate beyond a specific threshold, then the disease begins to express itself phenotypically. The process of biological ageing is one of the most significant factors in this aspect as it is also involved in the decline in homeostasis, maintenance and integrity.The process of atherogenesis unfolds sequentially (step by step) in an interconnected loop of pathologic changes in vascular biology. Such changes are involved in ‘switching’ of vascular cells towards atherosclerosis.

Systemic sclerosis (SSc) is an autoimmune rheumatic disease characterized by vasculopathy, inflammation and fibrosis of the skin and internal organs. The aetiology of SSc is largely unknown, and its pathogenesis is complex and remains poorly understood. In this thesis we investigated several mechanisms that regulate the inflammatory and fibrotic processes in patients with SSc. The studies presented in this thesis demonstrate several key dysregulated mechanisms that contribute for both inflammation and fibrosis on going in patients with SSc. The low expression of the transcription factor of RUNX3 alters dendritic cell function in patients with SSc and contributes to enhanced fibrosis; Angiopoietin 2 is increased in SSc patients and induces a pro-inflammatory response in monocytes; the CXCL4 chemokine drives fibrosis through multiple cell types; Semaphorin 4A levels are increased in SSc patients and activates T helper cells and contributes to the inflammatory and fibrotic phenotype of fibroblasts from SSc patients; the matricellular protein SPARC induces a pro-fibrotic phenotype in dermal fibroblasts from SSc patients, through the TGFβ signalling; the immune inhibitory receptor LAIR-1 is upregulated in inflammatory conditions and upon activation regulates cytokine production; in immune cells from SSc patients LAIR-1 is functional, however the fibrotic collagen products ineffectively activate LAIR-1, compromising its inhibitory function. Overall, our studies provide novel potential therapeutic targets, offering new opportunities for SSc patients, but we also demonstrate the heterogeneous mechanisms involved in the SSc pathophysiology, indicating the need for a better biological characterization of the disease and an ultimate need for personalized medicine.

Systemic sclerosis (SSc) is an autoimmune rheumatic disease characterized by vasculopathy, inflammation and fibrosis of the skin and internal organs. The aetiology of SSc is largely unknown, and its pathogenesis is complex and remains poorly understood. In this thesis we investigated several mechanisms that regulate the inflammatory and fibrotic processes in patients with SSc. The studies presented in this thesis demonstrate several key dysregulated mechanisms that contribute for both inflammation and fibrosis on going in patients with SSc. The low expression of the transcription factor of RUNX3 alters dendritic cell function in patients with SSc and contributes to enhanced fibrosis; Angiopoietin 2 is increased in SSc patients and induces a pro-inflammatory response in monocytes; the CXCL4 chemokine drives fibrosis through multiple cell types; Semaphorin 4A levels are increased in SSc patients and activates T helper cells and contributes to the inflammatory and fibrotic phenotype of fibroblasts from SSc patients; the matricellular protein SPARC induces a pro-fibrotic phenotype in dermal fibroblasts from SSc patients, through the TGFβ signalling; the immune inhibitory receptor LAIR-1 is upregulated in inflammatory conditions and upon activation regulates cytokine production; in immune cells from SSc patients LAIR-1 is functional, however the fibrotic collagen products ineffectively activate LAIR-1, compromising its inhibitory function. Overall, our studies provide novel potential therapeutic targets, offering new opportunities for SSc patients, but we also demonstrate the heterogeneous mechanisms involved in the SSc pathophysiology, indicating the need for a better biological characterization of the disease and an ultimate need for personalized medicine.

Objectives: The purpose of this study was to determine if elevated concentration of soluble receptor tunica interna endothelial cell kinase-2 (Tie-2) in the amniotic fluid represent a risk factor for the subsequent development of preeclampsia (PE). Study design: Amniotic fluid samples were collected as a part of routine clinical diagnostics from women referred to clinical care due to genetic indications. A total of 12 women with preeclampsia and 26 normotensive pregnant women were included in the study. Mean gestational age at amniocentesis was 17.92 weeks of pregnancy in preeclampsia and 17.88 in control group, respectively. Concentrations of sTie-2 in the amniotic fluid were determined by a standardized enzyme immunoassay. Results: Median concentration of Tie-2 in the amniotic fluid of PE patients was lower (median 1.109 ng/ml) compared with normotensive pregnant women (median 1.433 ng/Ml) but the difference was not statistically significant (p = 0.2973). Concentration of sTie-2 in the amniotic fluid did not significantly correlate with maternal age, gestational age at amniocentesis or delivery, as well as weight or length at birth. A difference in the gestational age at delivery in PE patients (mean 37.7 weeks) and normotensive pregnant controls (mean 39.8 weeks) was statistically significant (p = 0.0003). Birth weight and length of children delivered by PE women (mean 2863.3 g and 48.3 cm) were significantly lower compared with normal pregnancies (mean 3591.2 g and 51.4 cm, p = 0.0002 and p = 0.006, respectively). Conclusion: Our results suggest that amniotic fluid concentrations of sTie-2 do not predict development of PE and that further studies on biomarkers as predictors of PE should include other angiogenic biological response modifiers.

Heart failure (HF) is a growing public health burden, with high prevalence and mortality rates. A proportion of patients with HF have a normal ventricular ejection fraction (EF), referred to as HF with preserved EF (HFpEF), as opposed to patients with HF with reduced ejection fraction (HFrEF). HFpEF currently accounts for about 50% of all HF patients, and its prevalence is rising. Angiopoietins (ANGPTs), vascular endothelial growth factors (VEGFs) and secretory phospholipases A2 (sPLA2s) are proinflammatory mediators and key regulators of endothelial cells.

BACKGROUND: COVID-19 presents a spectrum of signs and symptoms in pregnant women that might resemble preeclampsia. Differentiation between severe COVID-19 and preeclampsia is difficult in some cases. OBJECTIVE: To study biomarkers of endothelial damage, coagulation, innate immune response, and angiogenesis in preeclampsia and COVID-19 in pregnancy in addition to in vitro alterations in endothelial cells exposed to sera from pregnant women with preeclampsia and COVID-19. STUDY DESIGN: Plasma and sera samples were obtained from pregnant women with COVID-19 infection classified into mild (n=10) or severe (n=9) and from women with normotensive pregnancies as controls (n=10) and patients with preeclampsia (n=13). A panel of plasmatic biomarkers was assessed, including vascular cell adhesion molecule-1, soluble tumor necrosis factor-receptor I, heparan sulfate, von Willebrand factor antigen (activity and multimeric pattern), a2-antiplasmin, C5b9, neutrophil extracellular traps, placental growth factor, soluble fms-like tyrosine kinase-1, and angiopoietin 2. In addition, microvascular endothelial cells were exposed to patients' sera, and changes in the cell expression of intercellular adhesion molecule 1 on cell membranes and von Willebrand factor release to the extracellular matrix were evaluated through immunofluorescence. Changes in inflammation cell signaling pathways were also assessed by of p38 mitogen-activated protein kinase phosphorylation. Statistical analysis included univariate and multivariate methods. RESULTS: Biomarker profiles of patients with mild COVID-19 were similar to those of controls. Both preeclampsia and severe COVID-19 showed significant alterations in most circulating biomarkers with distinctive profiles. Whereas severe COVID-19 exhibited higher concentrations of vascular cell adhesion molecule-1, soluble tumor necrosis factor-a receptor I, heparan sulfate, von Willebrand factor antigen, and neutrophil extracellular traps, with a significant reduction of placental growth factor compared with controls, preeclampsia presented a marked increase in vascular cell adhesion molecule-1 and soluble tumor necrosis factor-a receptor I (significantly increased compared with controls and patients with severe COVID-19), with a striking reduction in von Willebrand factor antigen, von Willebrand factor activity, and a2-antiplasmin. As expected, reduced placental growth factor, increased soluble fms-like tyrosine kinase-1 and angiopoietin 2, and a very high soluble fms-like tyrosine kinase-1 to placental growth factor ratio were also observed in preeclampsia. In addition, a significant increase in C5b9 and neutrophil extracellular traps was also detected in preeclampsia compared with controls. Principal component analysis demonstrated a clear separation between patients with preeclampsia and the other groups (first and second components explained 42.2% and 13.5% of the variance), mainly differentiated by variables related to von Willebrand factor, soluble tumor necrosis factor-receptor I, heparan sulfate, and soluble fms-like tyrosine kinase-1. Von Willebrand factor multimeric analysis revealed the absence of von Willebrand factor high-molecular-weight multimers in preeclampsia (similar profile to von Willebrand disease type 2A), whereas in healthy pregnancies and COVID-19 patients, von Willebrand factor multimeric pattern was normal. Sera from both preeclampsia and severe COVID-19 patients induced an overexpression of intercellular adhesion molecule 1 and von Willebrand factor in endothelial cells in culture compared with controls. However, the effect of preeclampsia was less pronounced than the that of severe COVID-19. Immunoblots of lysates from endothelial cells exposed to mild and severe COVID-19 and preeclampsia sera showed an increase in p38 mitogen-activated protein kinase phosphorylation. Patients with severe COVID-19 and preeclampsia were statistically different from controls, suggesting that both severe COVID-19 and preeclampsia sera can activate inflammatory signaling pathways. CONCLUSION: Although similar in in vitro endothelial dysfunction, preeclampsia and severe COVID-19 exhibit distinctive profiles of circulating biomarkers related to endothelial damage, coagulopathy, and angiogenic imbalance that could aid in the differential diagnosis of these entities.

Chronic obstructive pulmonary disease (COPD) is characterized by chronic inflammation, predominantly affecting the lung parenchyma and peripheral airways, that results in progressive and irreversible airflow obstruction. COPD development is promoted by persistent pulmonary inflammation in response to several stimuli (e.g., cigarette smoke, bacterial and viral infections, air pollution, etc.). Angiogenesis, the formation of new blood vessels, and lymphangiogenesis, the formation of new lymphatic vessels, are features of airway inflammation in COPD. There is compelling evidence that effector cells of inflammation (lung-resident macrophages and mast cells and infiltrating neutrophils, eosinophils, basophils, lymphocytes, etc.) are major sources of a vast array of angiogenic (e.g., vascular endothelial growth factor-A (VEGF-A), angiopoietins) and/or lymphangiogenic factors (VEGF-C, -D). Further, structural cells, including bronchial and alveolar epithelial cells, endothelial cells, fibroblasts/myofibroblasts, and airway smooth muscle cells, can contribute to inflammation and angiogenesis in COPD. Although there is evidence that alterations of angiogenesis and, to a lesser extent, lymphangiogenesis, are associated with COPD, there are still many unanswered questions.

Purpose: Defects in the iridocorneal angle tissues, including the trabecular meshwork (TM) and Schlemm’s canal (SC), impair aqueous humor flow and increase the intraocular pressure (IOP), eventually resulting in glaucoma. Activation of endothelial tyrosine kinase receptor Tie2 by angiopoietin-1 (Angpt1) has been demonstrated to be essential for SC formation, but roles of the other two Tie2 ligands, Angpt2 and Angpt4, have been controversial or not yet characterized, respectively. Methods: Angpt4 expression was investigated using genetic cell fate mapping and reporter mice. Congenital deletion of Angpt2 and Angpt4 and tamoxifen-inducible deletion of Angpt1 in mice were used to study the effects of Angpt4 deletion alone and in combination with the other angiopoietins. SC morphology was examined with immunofluorescent staining. IOP measurements, electron microscopy, and histologic evaluation were used to study glaucomatous changes. Results: Angpt4 was postnatally expressed in the TM. While Angpt4 deletion alone did not affect SC and Angpt4 deletion did not aggravate Angpt1 deletion phenotype, absence of Angpt4 combined with Angpt2 deletion had detrimental effects on SC morphology in adult mice. Consequently, Angpt2−/−;Angpt4−/− mice displayed glaucomatous changes in the eye. Mice with Angpt2 deletion alone showed only moderate SC defects, but Angpt2 was necessary for proper limbal vasculature development. Mechanistically, analysis of Tie2 phosphorylation suggested that Angpt2 and Angpt4 cooperate as agonistic Tie2 ligands in maintaining SC integrity. Conclusions: Our results indicated an additive effect of Angpt4 in SC maintenance and Tie2 activation and a spatiotemporally regulated interplay between the angiopoietins in the mouse iridocorneal angle.

The current study determined the natural angiogenic molecules using an unbiased metabolomics approach. A chick chorioallantoic membrane (CAM) model was used to examine pro- and antiangiogenic molecules, followed by gas chromatography–mass spectrometry (GCMS) analysis. Vessel formation was analyzed quantitatively using the angiogenic index (p < 0.05). At embryonic day one, a white streak or circle area was observed when vessel formation begins. GCMS analysis and database search demonstrated that angiogenesis may initiate when oleic, cholesterol, and linoleic acids increased in the area of angiogenic reactions. The gain of function study was conducted by the injection of cholesterol and oleic acid into a chick embryo to determine the role of each lipid in angiogenesis. We propose that oleic acid, cholesterol, and linoleic acid are natural molecules that set the platform for the initiation stage of angiogenesis before other proteins including the vascular endothelial growth factor, angiopoietin, angiotensin, and erythropoietin join as the angiome in sprout extension and vessel maturation.

Psoriasis is an autoimmune, chronic disease determined by environmental and genetic factors. The occurrence of psoriasis is accompanied by metabolic diseases, cardiovascular diseases (CVD) and depression, disturbances on interpersonal interactions and a tendency towards social isolation. Regardless of the form of psoriasis and the severity of the disease, early arterial lesions are recorded in arterial vessels of patients. Nevertheless, the chance of CVD is higher in the population of patients with severe psoriasis than in patients with mild to moderate psoriasis. The correlation between the presence of atherosclerotic plaque and psoriatic plaque is partially explained by: (1) a similar inflammatory pathway - via the T helper cells, (2) impaired angiogenesis, and (3) endothelial dysfunction. In the considered tests, the diagnostic tools used showed a reduced level of endothelial progenitor cells in the circulation of patients with psoriasis. Endogenous angiopoietin stimulation in patients with psoriasis leads to deterioration of endothelial regeneration, atherosclerosis which secondarily contributes to the progression of heart failure. Clinical and experimental data confirm the potential of immunomodulatory methods to combat both autoimmune and cardiovascular diseases through the use of immunosuppressive drugs. Full understanding of the way in which CVD develops in patients with autoimmune diseases would enable the implementation of targeted cell therapy allowing the quality and life expectancy of patients to be improved. Modern cellular diagnostic tools allow the use of highly specific biomarkers, which in the near future will enable a reduction in morbidity and mortality due to CVD.