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Introduction: Mesenchymal stem cells (MSCs) have been introduced as a promising treatment for diabetic wounds. The effects of stem cell therapy are thought to be caused by bioactive molecules secreted by stem cells. Stem cell-based gene therapies can target bioactive molecules. Therefore, treatment using conditioned medium (CM) derived from genetically engineered stem cells has been proposed as an alternative option for diabetic ulcer care. Methods: MSCs derived from human umbilical cords were obtained and engineered to overexpress the angiogenin-1 gene (MSCsAng1) through plasmid transfection. This study extracted conditioned medium from MSCs (MSC-CM) or MSCsAng1(MSCAng1-CM) for wound treatment applications. Via in vitro experiments, the proangiogenic effects of MSCAng1-CM were assessed via the migration and tube formation of human umbilical vein endothelial cells (HUVECs). Furthermore, the efficacy of MSCAng1-CM in promoting wound healing, re-epithelialization, hair follicle, and angiogenesis was evaluated via a diabetic mouse skin defect model. Results: In vitro assays demonstrated that MSCAng1-CM significantly enhanced HUVECs' functions, including migration and tube formation. In vivo assays revealed that MSCAng1-CM exhibited notable advancements in healing speed, re-epithelialization, hair follicle, and angiogenesis. Conclusion: These results indicate that MSCAng1-CM can promote wound healing in diabetic mice and make the vascular structure in regenerated tissues more stable without inducing tissue fibrosis, providing a new therapeutic strategy for treating diabetic skin wounds. This provides a valuable theoretical basis for further research on regenerative medicine and cell therapy. [ABSTRACT FROM AUTHOR]

Simple Summary: The ANGPT1 gene is crucial for angiogenesis and muscle growth. This study analyzed three ANGPT1 copy number variations (CNVs) in 417 Leizhou black goats using quantitative PCR (qPCR). Specifically, CNV-1 (ARS1_chr14:24950001-24953600), which overlaps with protein-coding regions, showed that a higher copy number (≥3) was significantly associated with increased ANGPT1 mRNA expression in muscle and improved traits such as carcass weight and muscle quality. These results suggest CNV-1's gain-of-copies genotype could be an effective marker for enhancing growth and meat quality in targeted breeding programs. The ANGPT1 gene plays a crucial role in the regulation of angiogenesis and muscle growth, with previous studies identifying copy number variations (CNVs) within this gene among Leizhou black goats. In this study, we investigated three ANGPT1 CNVs in 417 individuals of LZBG using quantitative PCR (qPCR), examining the impact of different CNV types on the ANGPT1 gene expression and their associations with growth and meat quality traits. Notably, the ANGPT1 CNV-1 (ARS1_chr14:24950001-24953600) overlaps with protein-coding regions and conserved domains; its gain-of-copies genotype (copies ≥ 3) was significantly correlated with ANGPT1 mRNA expression in muscle tissue (p < 0.01). Furthermore, the gain-of-copies genotype of CNV-1 demonstrated significant correlations with various phenotypic traits, including carcass weight, body weight, shear stress, chest circumference, and cross-sectional area of longissimus dorsi muscle. These findings indicate that the CNV-1 gain-of-copies genotype in the ANGPT1 gene may serve as a valuable marker for selecting Leizhou black goats exhibiting enhanced growth and muscular development characteristics, thereby holding potential applications in targeted breeding programs aimed at improving meat quality. [ABSTRACT FROM AUTHOR]

الملخص: أهداف البحث: يظل التئام العظام مشكلة عظام إكلينيكية حرجة. يعتمد العظم الذي هو عبارة عن أنسجة وعائية بشكل كبير على ارتباط زمني ومكاني ضيق بين الأوعية الدموية وخلايا العظام. وبالتالي، فإن تكوين الأوعية الدموية أمر بالغ الأهمية لنمو الهيكل العظمي وشفاء كسر العظام. كان الغرض من هذه الدراسة هو تقييم فعالية التطبيق الموضعي للعوامل المكونة للعظم مثل البروتين المخلق للعظام 9 وللأوعية مثل أنجيوبويتين 1، والجمع بينهما كمحفز عظمي في عملية التئام العظام. طرق البحث: تم استخدام ثمانية وأربعين من ذكور الجرذان البيضاء، التي يتراوح وزنها بين 300 و 400 جرام وتتراوح أعمارهم من 6 إلى 8 أشهر في هذه الدراسة. خضعت الحيوانات لعملية جراحية في الجانب الإنسي من عظم القصبة. في المجموعة الضابطة، تم تطبيق إسفنجة مرقئ قابلة للامتصاص محليا على عيب العظام، بينما تم فصل المجموعات التجريبية إلى ثلاث مجموعات. في المجموعة الأولى ، تم تطبيق 1 مجم من البروتين المخلق للعظام 9 محليا، وعولجت المجموعة الثانية بـ 1 مجم من أنجيوبويتين 1، وعولجت المجموعة الثالثة باستخدام مزيج محلي (0.5 مجم من البروتين المخلق للعظام 9 و 0.5 مجم من أنجيوبويتين 1). تم إصلاح جميع المجموعات التجريبية بإسفنجة مرقئة قابلة للامتصاص. تم التضحية بالفئران في اليوم 14 واليوم 28 بعد الجراحة. النتائج: التطبيق الموضعي لـ البروتين المخلق للعظام 9، أنجيوبويتين 1 وحده، وتوليفهما مع عيب في قصبة الساق يؤدي إلى تكوين الأنسجة العظمية وزيادة عدد الخلايا العظمية بشكل ملحوظ. لوحظ انخفاض تدريجي في عدد العظام التربيقية، وزيادة في منطقة التربيق، وعدم وجود فرق كبير في منطقة نخاع العظم.الاستنتاجات: إن الجمع بين البروتين المخلق للعظام 9 و أنجيوبويتين 1 له إمكانات علاجية في تعزيز عملية التئام عيوب العظام. يتم تنظيم تكون العظام وتكوين الأوعية بواسطة البروتين المخلق للعظام 9 و أنجيوبويتين 1. تعمل هذه العوامل معًا لتسريع عملية تجديد العظام بشكل أكثر كفاءة من أي عاملين على حدة. Abstract: Objectives: Bone healing remains a critical clinical orthopedic problem. Bone, which is a greatly vascularized tissue, depends on the tight temporal and spatial link between blood vessels and bone cells. Thus, angiogenesis is crucial for skeletal growth and bone fracture healing. The purpose of this study was to evaluate the efficacy of the local application of osteogenic and angiogenic factors such as bone morphogenetic protein 9 (BMP9) and angiopoietin 1 (Ang1), respectively, and their combination as an osteoinducer in the process of bone healing. Methods: Forty-eight male albino rats, weighing 300–400 g and aged 6–8 months, were utilized in this study. The animals underwent surgery on the medial side of the tibia bone. In the control group, an absorbable hemostatic sponge was locally applied to the bone defect, while experimental groups were separated into three groups. In Group I, 1 mg BMP9 was locally applied, Group II was treated with 1 mg Ang1, and Group III was treated with local application of a combination (0.5 mg BMP9 and 0.5 mg Ang1). All experimental groups were fixed with an absorbable hemostatic sponge. The rats were sacrificed on days 14 and 28 after surgery. Results: Local application of BMP9 alone, Ang1 alone, and their combination to a tibia defect caused osteoid tissue formation and significantly increased the number of bone cells. A gradual decrease in the number of trabecular bone, an increase in trabecular area, and no significant difference in the bone marrow area were noted. Conclusion: The combination of BMP9 and Ang1 has therapeutic potential in promoting the healing process of bone defects. Osteogenesis and angiogenesis are regulated by BMP9 and Ang1. These factors act together to accelerate bone regeneration more efficiently than either factor alone.

Background Individuals infected with HIV have an increased risk of developing cardiovascular disease; yet, the underlying mechanisms remain unknown. Recent evidence has implicated the Tie-2 tyrosine kinase receptor system and its associated ligands ANG1 (angiopoietin 1) and ANG2 (angiopoietin 2) in maintaining vascular homeostasis. In the general population, lower ANG1 levels and higher ANG2 levels are strongly correlated with the development of cardiovascular disease. In this study, we aim to investigate the associations of HIV infection with angiopoietin levels and endothelial dysfunction. Methods and Results In this cross-sectional study, we compared measures of ANG1, ANG2, and endothelial dysfunction using flow-mediated vasodilation of the brachial artery in 39 untreated subjects infected with HIV, 47 treated subjects infected with HIV, and 46 uninfected subjects from the SCOPE (Observational Study of the Consequences of the Protease Inhibitor Era) cohort. Compared with uninfected controls, treated individuals infected with HIV had 53.1% lower mean ANG1 levels (P

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IntroductionKaposiform lymphangiomatosis (KLA) is a rare and complex lymphatic anomaly with a poor prognosis. There is no standard treatment, and drug therapies are the most common therapeutic method. However, some patients' symptoms become gradually aggravated despite medical treatment. Splenectomy may be an alternative option when pharmacological therapies are ineffective.Materials and MethodsWe reviewed and evaluated the cases of 3 patients with KLA who ultimately underwent splenectomy. Results: The lesions were diffusely distributed and involved the lungs and spleens of the 3 patients. Laboratory examinations revealed that all three patients had thrombocytopenia and reduced fibrinogen levels. All patients underwent symptomatic splenectomy after the medication failed. Surprisingly, their symptoms greatly improved. Histopathological investigation of the splenic lesions of the three patients confirmed the diagnosis of KLA. Immunohistochemical staining showed positivity for CD31, CD34, podoplanin, Prox-1 and angiopoietin 2 (Ang-2).DiscussionThis study aimed to review the features of KLA patients treated by splenectomy and explore the underlying link between splenectomy and prognosis. The reason for the improvement after splenectomy may be related to increased Ang-2 levels and platelet activation in patients with KLA. Future research should seek to develop more targeted drugs based on molecular findings, which may give new hope for the treatment of KLA.

Introduction: There are few circulating biomarkers for valvular heart disease. Angiopoietin (Ang) 1, Ang2, and vascular endothelial growth factor are important inflammation-associated cytokines. The aim of this study was to investigate the clinical significance and association of Ang1, Ang2, and vascular endothelial growth factor in valvular heart disease. Methods: This is a retrospective study; a total of 62 individuals (valvular heart disease patients [n=42] and healthy controls [n=20]) were included. Plasma levels of Ang1, Ang2, and vascular endothelial growth factor were detected by enzyme-linked immunosorbent assays. We retrospectively collected the baseline characteristics and short-term outcomes; logistic regression was performed to identify predictor for short-term mortality. Results: Ang2 was significantly decreased in the valvular heart disease group compared with the healthy control group (P=0.023), while no significant difference was observed in the Ang1 and vascular endothelial growth factor levels. The Ang2 level of New York Heart Association (NYHA) I/II patients -- but not NYHA III/IV patients -- was significantly decreased compared with that of healthy control individuals (NYHA I/II: P=0.017; NYHA III/IV: P=0.485). Univariable logistic regression analysis indicated that Ang2 was a significant independent predictor for short-term mortality (odds ratio 18.75, P=0.033, 95% confidence interval 8.08-102.33). Ang1 was negatively correlated with Ang2 (P=0.032, Pearson's correlation coefficient = -0.317) and was positively correlated with vascular endothelial growth factor (P=0.019, Pearson's correlation coefficient = 0.359). Conclusion: Ang2 might serve as a therapeutic and prognostic target for valvular heart disease. [ABSTRACT FROM AUTHOR]

Abstract Background Neutrophils induce the synthesis and release of angiopoietin 1 (Ang1), a cytosolic growth factor involved in angiogenesis and capable of inducing several pro-inflammatory activities in neutrophils. Neutrophils also synthesize and release neutrophil extracellular traps (NETs), comprised from decondensed nuclear DNA filaments carrying proteins such as neutrophil elastase (NE), myeloperoxidase (MPO), proteinase 3 (PR3) and calprotectin (S100A8/S100A9), which together, contribute to the innate immune response against pathogens (e.g., bacteria). NETs are involved in various pathological conditions through pro-inflammatory, pro-thrombotic and endothelial dysfunction effects and have recently been found in heart failure (HF) and type 2 diabetes (T2DM) patients. The aim of the present study was to investigate the role of NETs on the synthesis and release of Ang1 by the neutrophils in patients with T2DM and HF with preserved ejection fraction (HFpEF) (stable or acute decompensated; ADHFpEF) with or without T2DM. Results Our data show that at basal level (PBS) and upon treatment with LPS, levels of NETs are slightly increased in patients suffering from T2DM, HFpEF ± T2DM and ADHF without (w/o) T2DM, whereas this increase was significant in ADHFpEF + T2DM patients compared to healthy control (HC) volunteers and ADHFpEF w/o T2DM. We also observed that treatments with PMA or A23187 increase the synthesis of Ang1 (from 150 to 250%) in HC and this effect is amplified in T2DM and in all cohorts of HF patients. Ang1 is completely released (100%) by neutrophils of all groups and does not bind to NETs as opposed to calprotectin. Conclusions Our study suggests that severely ill patients with HFpEF and diabetes synthesize and release a greater abundance of NETs while Ang1 exocytosis is independent of NETs synthesis.

Objective To investigate the effect of PLGA-PEG scaffold incorporating angiopoietin 1(Ang1) loaded nanoparticle that was injected into the infarcted area of rat heart to protect the heart from infarction and explore potential mechanisms. Methods Rat models of myocardial infarction were replicated,and one week later SD rats were randomly divided into 3 groups:Ang1-PLGA-PEG injection group [injected with 100 μL nanoparticle suspension, about (1.61±0.05)μg Ang1](n=9),Ang1 injection group[injected with PBS solution of angiopoietin1(100 μL, 25 ng/μL)](n=8),the model control group(injected with 100 μL PBS solution)(n=8). Four weeks after injection,cardiac function was examined by echocardiography,scar tissue hyperplasia was measured by Masson staining, cardiomyocyte apoptosis and angiogenesis were detected by immunofluorescence. Results In comparison with other two groups,Ang1-PLGA-PEG injection group showed an increased blood vessel density in the infarcted area and maturity(P＜0.05),which prevented cardiomyocyte apoptosis (P＜0.05) The area of myocardial infarction was significantly decreased(P＜0.05), the remodeling of cardiomyopathy was reduced and these changes improved cardiac function (P＜0.05). Compared with the model control group, pure Ang1 injected into the surrounding area did not show curative effect (P＜0.05). Conclusions Injection of Ang1-PLGA-PEG nanoparticles into the infarcted area of left ventricle may promote vascular proliferation and facilitate the survival of cardiomyocytes,It provides an experimental basis for clinical application.

Aims/hypothesis: Diabetic cardiomyopathy (DCM) is a serious and under-recognised complication of diabetes. The first sign is diastolic dysfunction, which progresses to heart failure. The pathophysiology of DCM is incompletely understood but microcirculatory changes are important. Endothelial glycocalyx (eGlx) plays multiple vital roles in the microcirculation, including in the regulation of vascular permeability, and is compromised in diabetes but has not previously been studied in the coronary microcirculation in diabetes. We hypothesised that eGlx damage in the coronary microcirculation contributes to increased microvascular permeability and hence to cardiac dysfunction. Methods: We investigated eGlx damage and cardiomyopathy in mouse models of type 1 (streptozotocin-induced) and type 2 (db/db) diabetes. Cardiac dysfunction was determined by echocardiography. We obtained eGlx depth and coverage by transmission electron microscopy (TEM) on mouse hearts perfusion-fixed with glutaraldehyde and Alcian Blue. Perivascular oedema was assessed from TEM images by measuring the perivascular space area. Lectin-based fluorescence was developed to study eGlx in paraformaldehyde-fixed mouse and human tissues. The eGlx of human conditionally immortalised coronary microvascular endothelial cells (CMVECs) in culture was removed with eGlx-degrading enzymes before measurement of protein passage across the cell monolayer. The mechanism of eGlx damage in the diabetic heart was investigated by quantitative reverse transcription-PCR array and matrix metalloproteinase (MMP) activity assay. To directly demonstrate that eGlx damage disturbs cardiac function, isolated rat hearts were treated with enzymes in a Langendorff preparation. Angiopoietin 1 (Ang1) is known to restore eGlx and so was used to investigate whether eGlx restoration reverses diastolic dysfunction in mice with type 1 diabetes. Results: In a mouse model of type 1 diabetes, diastolic dysfunction (confirmed by echocardiography) was associated with loss of eGlx from CMVECs and the development of perivascular oedema, suggesting increased microvascular permeability. We confirmed in vitro that eGlx removal increases CMVEC monolayer permeability. We identified increased MMP activity as a potential mechanism of eGlx damage and we observed loss of syndecan 4 consistent with MMP activity. In a mouse model of type 2 diabetes we found a similar loss of eGlx preceding the development of diastolic dysfunction. We used isolated rat hearts to demonstrate that eGlx damage (induced by enzymes) is sufficient to disturb cardiac function. Ang1 restored eGlx and this was associated with reduced perivascular oedema and amelioration of the diastolic dysfunction seen in mice with type 1 diabetes. Conclusions/interpretation: The association of CMVEC glycocalyx damage with diastolic dysfunction in two diabetes models suggests that it may play a pathophysiological role and the enzyme studies confirm that eGlx damage is sufficient to impair cardiac function. Ang1 rapidly restores the CMVEC glycocalyx and improves diastolic function. Our work identifies CMVEC glycocalyx damage as a potential contributor to the development of DCM and therefore as a therapeutic target. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: There are few circulating biomarkers for valvular heart disease. Angiopoietin (Ang) 1, Ang2, and vascular endothelial growth factor are important inflammation-associated cytokines. The aim of this study was to investigate the clinical significance and association of Ang1, Ang2, and vascular endothelial growth factor in valvular heart disease. Methods: This is a retrospective study; a total of 62 individuals (valvular heart disease patients [n=42] and healthy controls [n=20]) were included. Plasma levels of Ang1, Ang2, and vascular endothelial growth factor were detected by enzyme-linked immunosorbent assays. We retrospectively collected the baseline characteristics and short-term outcomes; logistic regression was performed to identify predictor for short-term mortality. Results: Ang2 was significantly decreased in the valvular heart disease group compared with the healthy control group (P=0.023), while no significant difference was observed in the Ang1 and vascular endothelial growth factor levels. The Ang2 level of New York Heart Association (NYHA) I/II patients — but not NYHA III/IV patients — was significantly decreased compared with that of healthy control individuals (NYHA I/II: P=0.017; NYHA III/IV: P=0.485). Univariable logistic regression analysis indicated that Ang2 was a significant independent predictor for short-term mortality (odds ratio 18.75, P=0.033, 95% confidence interval 8.08-102.33). Ang1 was negatively correlated with Ang2 (P=0.032, Pearson’s correlation coefficient =-0.317) and was positively correlated with vascular endothelial growth factor (P=0.019, Pearson’s correlation coefficient = 0.359). Conclusion: Ang2 might serve as a therapeutic and prognostic target for valvular heart disease.

Cerebral damage following cerebral ischemia/reperfusion injury affects the neurological deficits and motor impairment of stroke patients in the long-term period. Angiogenesis, the essential process for restoration of cerebral blood flow (CBF) in the ischemic brain, promotes the recovery of neurological function following ischemia. The aim of this study was to investigate the long-term effects of morin on angiogenesis and functional outcomes in a middle cerebral artery occlusion (MCAO) and reperfusion model. Male Wistar rats were subjected to MCAO, and they were administered 30 mg/kg of morin at reperfusion via i.p. injection daily for 14 days. Fourteen days after I/R injury, the rats were evaluated for the brain damage, and angiogenic factors involved in Ang1/Tie-2 and Wnt/β-catenin signaling. In addition, at 1, 7, and 14 days after reperfusion, rotarod and pole tests were performed to investigate the functional recovery. We found morin significantly reduced the infarct size, blood–brain barrier (BBB) leakage, and apoptotic cells at 14 days after I/R injury. It also promoted angiogenesis via boosting the expression of angiogenic proteins, such as angiopoietin 1 (Ang1), Tie-2, Wnt3α, β-catenin, and cyclin D1. Morin-mediated angiogenesis was confirmed by a significant increase in microvessel's density in the penumbra area and an increase in von Willebrand factor (vWF) protein expression of the morin-treated rats. Moreover, the rotarod and pole tests also demonstrated morin increased functional recovery in the morin-treated rats compared to the vehicle rats. Therefore, our data exposed that morin promotes angiogenesis and improves functional outcomes in MCAO and reperfusion rats. [ABSTRACT FROM AUTHOR]

Background Individuals infected with HIV have an increased risk of developing cardiovascular disease; yet, the underlying mechanisms remain unknown. Recent evidence has implicated the Tie‐2 tyrosine kinase receptor system and its associated ligands ANG1 (angiopoietin 1) and ANG2 (angiopoietin 2) in maintaining vascular homeostasis. In the general population, lower ANG1 levels and higher ANG2 levels are strongly correlated with the development of cardiovascular disease. In this study, we aim to investigate the associations of HIV infection with angiopoietin levels and endothelial dysfunction. Methods and Results In this cross‐sectional study, we compared measures of ANG1, ANG2, and endothelial dysfunction using flow‐mediated vasodilation of the brachial artery in 39 untreated subjects infected with HIV, 47 treated subjects infected with HIV, and 46 uninfected subjects from the SCOPE (Observational Study of the Consequences of the Protease Inhibitor Era) cohort. Compared with uninfected controls, treated individuals infected with HIV had 53.1% lower mean ANG1 levels (P

Background: Neutrophils induce the synthesis and release of angiopoietin 1 (Ang1), a cytosolic growth factor involved in angiogenesis and capable of inducing several pro-inflammatory activities in neutrophils. Neutrophils also synthesize and release neutrophil extracellular traps (NETs), comprised from decondensed nuclear DNA filaments carrying proteins such as neutrophil elastase (NE), myeloperoxidase (MPO), proteinase 3 (PR3) and calprotectin (S100A8/S100A9), which together, contribute to the innate immune response against pathogens (e.g., bacteria). NETs are involved in various pathological conditions through pro-inflammatory, pro-thrombotic and endothelial dysfunction effects and have recently been found in heart failure (HF) and type 2 diabetes (T2DM) patients. The aim of the present study was to investigate the role of NETs on the synthesis and release of Ang1 by the neutrophils in patients with T2DM and HF with preserved ejection fraction (HFpEF) (stable or acute decompensated; ADHFpEF) with or without T2DM. Results: Our data show that at basal level (PBS) and upon treatment with LPS, levels of NETs are slightly increased in patients suffering from T2DM, HFpEF ± T2DM and ADHF without (w/o) T2DM, whereas this increase was significant in ADHFpEF + T2DM patients compared to healthy control (HC) volunteers and ADHFpEF w/o T2DM. We also observed that treatments with PMA or A23187 increase the synthesis of Ang1 (from 150 to 250%) in HC and this effect is amplified in T2DM and in all cohorts of HF patients. Ang1 is completely released (100%) by neutrophils of all groups and does not bind to NETs as opposed to calprotectin. Conclusions: Our study suggests that severely ill patients with HFpEF and diabetes synthesize and release a greater abundance of NETs while Ang1 exocytosis is independent of NETs synthesis. [ABSTRACT FROM AUTHOR]

Abstract Background Damage to the endothelium due to ischemia reperfusion injury (IRI) leads to a disruption of the microvasculature, which could be influenced by angiopoietin 1 via its effects on endothelium. We investigated the physiological and therapeutic roles of angiopoietin 1 in renal IRI using angiopoietin 1 knockout and over-expression mice. Methods Renal IRI was induced by clamping the right renal artery seven days after left uninephrectomy for 25 min followed by reperfusion. A whole body angiopoietin 1 knockout was achieved by induction with tamoxifen. The renal tubule over-expression of angiopoietin 1 was induced by doxycycline. Results In the normal mice, the renal expression of angiopoietin 1 increased 7 days to 14 days after IRI. The angiopoietin 1 knockout caused a delay in the recovery of renal function, less tubular regeneration and more residual tubular necrosis. The endothelial density was lower and the VE-cadherin protein loss was greater in the knockout mice. The over-expression of angiopoietin 1 attenuated the tubular necrosis and renal function impairment 1 and 3 days after IRI. The loss of the endothelium was ameliorated in the over-expression mice. This protective effect was associated with the up-regulation of the gene expression of epidermal growth factor, hepatocyte growth factor, and insulin like growth factor-1 and less tubular apoptosis. The over-expression of angiopoietin 1 stimulated tumor necrosis factor-α, C-C chemokine receptor type 2 and CX3C chemokine receptor 1 inflammatory gene expression, but did not influence macrophage infiltration. Conclusions Altogether, the augmentation and downregulation of angiopoietin 1 attenuated renal damage and impaired renal recovery, respectively, by influencing the survival/regeneration of the endothelium. The manipulation of angiopoietin 1 represents a novel therapeutic approach for the treatment of ischemic kidney injury.

Background: Gastrointestinal (GI) dysfunction is observed clinically after spinal cord injury (SCI) and contributes to the diminished long‐term quality of life. Our study examined the acute and chronic GI vascular changes that occur following SCI. We demonstrated that the GI vascular tract in SCI mice becomes compromised during the acute phase of injury and persists into the chronic phase of injury. Methods: Gastrointestinal vasculature permeability was measured using dynamic contrast‐enhanced magnetic resonance imaging (DCE MRI) at 48 hours, and 2 and 4 weeks following contusion spinal cord injury. Angiopoietin‐1, a vascular stabilizing protein, was administered intravenously following injury. Intestinal contractile activity assessments were performed following the last imaging session. Key results: Our results indicated that a single administration of Ang‐1 reduced vascular permeability at 48 hours but the effect was only transient. However, when the treatment paradigm was changed from a single administration to multiple administrations of Ang‐1 following contusion injury, our DCE MRI data indicated a significant decrease in GI vascular permeability 4 weeks after injury compared with vehicle control treated animals. This improved GI vascular permeability was associated with improved sustained intestinal contractile activity. We also demonstrated that Ang‐1 reduced the expression of sICAM‐1 in the ileum compared with the saline‐treated group. Conclusions and inferences: We show that the GI vasculature is compromised in the acute and chronic phase of injury following spinal contusion. Our results also indicate that multiple administrations of Ang‐1 can attenuate GI vascular permeability, possibly reduce inflammation, and improve sustained agonist‐induced contraction compared with saline treatment. [ABSTRACT FROM AUTHOR]

A root cause for the development and progression of primary open-angle glaucoma might be the loss of the Schlemm’s canal (SC) cell function due to an impaired Angiopoietin-1 (Angpt-1)/Tie2 signaling. Current therapeutic options fail to restore the SC cell function. We propose Angpt-1 mimetic nanoparticles (NPs) that are intended to bind in a multivalent manner to the Tie2 receptor for successful receptor activation. To this end, an Angpt-1 mimetic peptide was coupled to a poly(ethylene glycol)-poly(lactic acid) (PEG-PLA) block co-polymer. The modified polymer allowed for the fabrication of Angpt-1 mimetic NPs with a narrow size distribution (polydispersity index < 0.2) and the size of the NPs ranging from about 120 nm (100% ligand density) to about 100 nm (5% ligand density). NP interaction with endothelial cells (HUVECs, EA.hy926) as surrogate for SC cells and fibroblasts as control was investigated by flow cytometry and confocal microscopy. The NP–cell interaction strongly depended on the ligand density and size of NPs. The cellular response to the NPs was investigated by a Ca2+ mobilization assay as well as by a real-time RT-PCR and Western blot analysis of endothelial nitric oxide synthase (eNOS). NPs with a ligand density of 25% opposed VEGF-induced Ca2+ influx in HUVECs significantly which could possibly increase cell relaxation and thus aqueous humor drainage, whereas the expression and synthesis of eNOS was not significantly altered. Therefore, we suggest Angpt-1 mimetic NPs as a first step towards a causative therapy to recover the loss of SC cell function during glaucoma.

Understanding the molecular factors involved in the development of uterine myomas may result in the use of pharmacological drugs instead of aggressive surgical treatment. ANG1, CaSR, and FAK were examined in myoma and peripheral tissue samples taken from women after myoma surgery and in normal uterine muscle tissue samples taken from the control group. Tests were performed using tissue microarray immunohistochemistry. No statistically significant differences in ANG1 expression between the tissue of the myoma, the periphery, and the normal uterine muscle tissue of the control group were recorded. The CaSR value was reduced in the myoma and peripheral tissue and normal in the group of women without myomas. FAK expression was also lower in the myoma and periphery compared to the healthy uterine myometrium. Calcium supplementation could have an effect on stopping the growth of myomas.

The regulation of endothelial cell (EC) permeability is critical for the physiological homeostasis of blood vessels and tissues. The elevation of pro-inflammatory cytokines is highly associated with lesions, such as the increased vascular permeability of diabetic retinas. We have previously reported that interleukin-6 (IL-6) increases EC permeability through the downregulation of tight junction protein expression. Angiopoietin 1 (Ang1) has an anti-permeability function, but the effect of Ang1 on vascular permeability induced by inflammatory cytokines is unclear. In the present study, we investigated the effect of Ang1 on IL-6-induced EC permeability and its underlying molecular mechanisms. We demonstrated that Ang1 inhibited the IL-6-induced increase in EC permeability by inhibiting the reductions in the levels of tight junction protein ZO-1 and occludin, which was related to the decrease in vascular endothelial growth factor (VEGF) secretion through the inhibition of STAT3 activation by Ang1. Mechanistically, Ang1 induced the dissociation of the tyrosine phosphatase SHP-1 from the Tie2 receptor and increased the binding of SHP-1 to JAK1, JAK2, and STAT3, which are IL-6 downstream signaling proteins. We conclude that SHP-1 plays an important role in the Ang1-induced inhibition of JAK/STAT3 signaling. These results provide evidence for a potential beneficial role of Ang1 in suppressing the vascular permeability induced by the pro-inflammatory cytokine IL-6 in diabetic retinopathy. • Ang1 inhibited the IL-6-induced increase in EC permeability by inhibiting the reduction of tight junction protein expression. • Ang1 induced the dissociation of the tyrosine phosphatase SHP-1 from the Tie2 receptor. • Ang1 increased the binding of SHP-1 to JAK1, JAK2, and STAT3 and inhibited IL-6 downstream signaling. [ABSTRACT FROM AUTHOR]

Purpose: Investigating whether pre-ovulatory follicular fluid (FF) levels of selected proteins differ between women who do or do not develop severe ovarian hyperstimulation syndrome (OHSS) and evaluate whether they potentially could guide a "freeze-all" strategy.Methods: FF was collected during a randomized controlled trial comparing OHSS in antagonist versus agonist protocol including 1050 women in their first assisted reproductive technology (ART) cycle during year 2009-2013. The present sub-study is a matched case-control study comparing FF levels of soluble urokinase plasminogen activator receptor (suPAR), C-reactive protein, placental growth factor, vascular endothelial growth factor, and angiopoietins 1 and 2 in OHSS cases (n = 25, severe OHSS, and ≥ 15 oocytes), high-risk controls (n = 25, no OHSS, and ≥ 15 oocytes), and low-risk controls (n = 25, no OHSS, and 5-8 oocytes).Results: FF level of suPAR differed significantly between the three groups (p = 0.018) with mean (SD) levels of 2.3 (0.4) μg/L, 2.6 (0.8) μg/L, and 2.8 (0.6) μg/L in OHSS cases, high-risk controls, and low-risk controls, respectively. Receiver operating characteristic curve analysis demonstrated that suPAR levels could predict severe OHSS (AUC 0.678; 95% CI 0.553-0.803) with a sensitivity of 64% and a specificity of 66%. None of the other investigated proteins differed between the three groups or between OHSS cases and combined controls.Conclusion: The pre-ovulatory FF level of suPAR was significantly lower in women developing severe OHSS, indicating that the plasminogen activator system could be involved in the pathophysiology of OHSS. However, suPAR did not provide a satisfying predictive value for the prediction of OHSS. [ABSTRACT FROM AUTHOR]

The sprouting of endothelial cells is the first step of tumor angiogenesis. Our previous study suggests that miR-153 suppresses breast tumor angiogenesis partially through targeting hypoxia-induced factor (HIF1α). In this study, we demonstrated that miR-153 also suppresses the migration and the tube formation of endothelial cells through directly targeting angiopoietin 1 (ANG1) in breast cancer cells. There was a negative correlation between miR-153 and ANG1 levels in breast cancer. miR-153 blocked the expression and secretion of ANG1 in breast cancer cells through binding to ANG1 mRNA. Conditioned medium from the breast cancer cell, MCF7, treated with miR-153 had no effect on the proliferation of HUVECs, but significantly inhibited the migration and tube formation of HUVECs, which could be rescued by overexpression of ANG1. In addition, miR-153 also directly inhibited the proliferation and migration of MCF7 through downregulation of ANG1. These findings suggest that miR-153 suppresses the activity of tumor cells and the migration and tube formation of endothelial cells by silencing ANG1. [ABSTRACT FROM AUTHOR]

Introduction: Laryngeal carcinoma is the most common malignant head-and-neck tumor. Due to the low survival rate and the inadequate response to chemotherapy, effective therapy remains a challenge. Objectives: Therefore, the identification of new therapeutic options that preserve the larynx is needed. Hesperidin (Hsp) is a nontoxic plant flavanone that has proven effective against cancer. Materials and Methods: Hence, the current in vivo and in vitro study was conducted to determine whether Hsp might suppress metastasis of cancer larynx. Results: In an in vivo mouse metastasis model, Hsp suppressed metastasis of human Hep2 laryngeal cancer cells to the livers and lungs. In vitro assays, Hsp significantly inhibited angiopoietin 1 secretion (an angiogenic promotor) and increased annexin-V (an apoptotic indicator) in Hep2 cell culture at relatively low levels (10 μM). Conclusions: These studies suggest that Hsp deserves further investigation as a possible treatment option for laryngeal cancer. [ABSTRACT FROM AUTHOR]

Background: Hypertensive disorders, fetal growth restriction and preterm birth are major obstetrical complications and are related to impaired placentation. Early identification of impaired placentation can advance clinical care by preventing or postpone adverse pregnancy outcome.Objectives: Determine whether sonographic assessed placental vascular development and concomitant changes in inflammation- and/or angiogenesis-related serumproteins differ in the first trimester between uncomplicated pregnancies and pregnancies with adverse outcome.Study Design: This prospective longitudinal study defines adverse pregnancy outcome as conditions associated with impaired placentation; fetal growth restriction, hypertensive disorder, preterm birth and placental abruption. The vascularization index, flow index, vascularization flow index and placental volume were determined at 8, 10 and 12 weeks pregnancy from 64 women using 3D power Doppler. Serum levels were analyzed for Angiopoetin-1 and -2, Leptin, VEGF-R, VEGF, and EGF.Results: The vascularization index and vascular flow index increased in uneventful pregnancies with almost 50% between 8 and 12 weeks, resulting in a ∼50% higher vascularization index at 12 weeks compared to women with an adverse pregnancy outcome. Women with an adverse pregnancy outcome (n = 13) had significantly lower indices and placental volumes at all time points measured and these indices did not increase between 8 and 12 weeks. Reduced vascular development was associated with increased Angiopoietin-1 levels at 8 and 12 weeks and increased Leptin levels at 8 weeks.Conclusions: Pregnancies with an adverse outcome caused by conditions associated with impaired placentation differ from uneventful pregnancies in having reduced placental vascularization accompanied by elevated circulating levels of Angiopoietin-1 and Leptin already in the first trimester. [ABSTRACT FROM AUTHOR]

The angiopoietin 1 (Ang1)/angiopoietin receptor (Tie2) signaling pathway may have a notable role in the pathogenesis of inflammatory diseases. The abnormal expression of angiopoietin 1 and Tie2 has also been reported in various malignant tumors, including papillary thyroid carcinoma (PTC). However, the role and mechanism of the Ang1/Tie2 pathway in the progression of PTC remains unclear. Therefore, the aims of the present study were to clarify this. Significantly high expression levels of Ang1 and Tie2 were observed in PTC tissues and cell lines. Furthermore, MTT and wound-healing assays revealed that the Ang1-mediated stimulation of human PTC cells resulted in increased proliferation and migration. Conversely, the downregulation of Tie2 levels using short hairpin RNA targeted at Tie2 abrogated the Ang1-mediated effect on cell proliferation and migration. In studying the expression of phosphoinositide-3 kinase (PI3K)/RAC serine/threonine-protein kinase (Akt) pathway, the upregulation of Ang1/Tie2 was found to be associated with the activation of the PI3K/Akt pathway in PTC. In conclusion, the data from the present study indicated that the Ang1/Tie2 induces PTC oncogenesis via the PI3K/Akt pathway, providing novel insights into human PTC therapy. [ABSTRACT FROM AUTHOR]

Introduction: Blood vessel formation by angiogenesis is essential for goitre development. Angiopoietin 1 (Ang-1),angiopoietin 2 (Ang-2) and Tie-2 receptor (rTie-2) are involved in part of angiogenesis. Ang-1 and rTie-2 expressionincreases in goitre.Aim: To determine serum concentrations (SC) of angiogenic cytokines of patients with goitre treated surgically.Material and mathods: Thirty-six patients with goitre aged 29-64 were examined. They were divided into groups: nontoxicnodular goitre (NTNG) and toxic goitre (TG). Each group was divided into subgroups: before and after surgery.The control group comprised 10 healthy subjects. Ang-1, Ang-2 and rTie-2 SC were measured in euthyroid subjects byELISA. Measurements were performed before the procedure and three months after.Results: Before surgery Ang-1 median (Me) SC in patients with TG was higher than in patients with NTNG (109 368pg/ml vs. 71 185 pg/ml) and in controls (109 368 pg/ml vs. 57 815 pg/ml). Ang-1 Me in TG patients was higher prior tothan after surgery (109 368 pg/ml vs. 65380 pg/ml). Ang-2 Me in TG patients was higher after than prior to surgery(4055 pg/ml vs. 3924 pg/ml). Significant correlations were found between Ang-1 and Tie-2 Me (r = 0.53) and Ang-2and Tie-2 (r = 0.58) in patients with NTNG before surgery and between Me Ang-2 and Tie-2 in patients with NTNGafter surgery (r = 0.89) and in controls (r = 0.77).Conclusions: Before surgery in patients with TG SC of Ang-1 was higher than in patients with NTNG and in controls.After surgery in patients with TG SC of Ang-1 decreased, and SC of Ang-2 increased. Significant correlations werefound between SC of Ang-2 and Tie-2 in patients with NTNG and in controls.

Our previous studies have found that stem cells conditioned medium (CM) facilitated functional recovery after stroke in non-diabetics. However, whether bone marrow stromal cells conditioned medium (BMSCs-CM) treatment after stroke in type 2 diabetic (T2DM) rats improve functional outcomes remains unclear. T2DM rats were induced and subjected to stroke then treated with or without BMSCs-CM. Functional outcomes and blood-brain barrier (BBB) leakage were performed, the expression of Angiopoietin (Ang) 1 and tyrosine kinase (Tie) 2 were also assessed. Our results showed that BMSCs-CM treatment significantly improved functional outcomes, decreased BBB leakage and the expression of Ang1 and Tie2 were also changed after BMSCs-CM treatment in type 2 diabetes after stroke. In conclusion, enhanced expression of Ang1 and Tie2 in ischemic brain after BMSCs-CM treatment of stroke may contribute to the improved functional recovery after stroke in type 2 diabetic rats. [ABSTRACT FROM AUTHOR]

Background/aim: The role of angiogenic factors in gastric cancer is not clear. We aimed to assess the role of vascular endothelial growth factor A (VEGFA), angiopoietin 1 (Ang-1), and placental growth factor (PlGF) in the prognosis of patients with advanced gastric cancer. Materials and methods: Thirty consecutive patients treated with a modified DCF (docetaxel, cisplatin, and fluorouracil) regimen were included in the study. The plasma VEGFA, Ang-1, and PlGF levels of the patients before treatment and following two cycles of chemotherapy were measured and evaluated as prognostic factors. Results: Poor performance status and lower Ang-1 levels were correlated with poor overall survival (OS). No significant correlation between VEGFA or PlGF and OS was found. An angiogenesis prognostic index (API) based on the levels of VEGFA, Ang-1, and PlGF was found to be highly correlated with OS. Performance status and API were found as independent prognostic factors for OS. Furthermore, a decrease in VEGFA by 25% from the pretreatment level was also found as a prognostic factor for OS independent of response to DCF regimen. Conclusion: Our results support the use of the new API including VEGFA, Ang-1, and PlGF levels in patients with advanced gastric cancer as a predictor of survival. [ABSTRACT FROM AUTHOR]

Background: The flowers of Carthamus tinctorius L. are widely used in traditional Chinese medicine to treat cerebrovascular and cardiovascular diseases. Hydroxysafflor yellow A (HSYA), the main constituent of C. tinctorius L. flowers, is known for its multiple biological activities. The present study investigated the effects of HSYA on angiogenesis in vitro and in a mouse hindlimb ischemia model. Methods: Using human umbilical vein endothelial cells (HUVEC) in vitro and a mouse hindlimb ischemia model in vivo, the angiogenic role of HSYA was evaluated. Results: HSYA significantly increased the capillary-like tube formation and migration of HUVEC. HSYA not only induced a rise in the expression of angiopoietin 1 and Tie-2 but it also increased phosphorylation of Tie- 2, Akt, and extracellular signal-regulated kinase 1/2. Furthermore, an anti-Tie-2 neutralizing antibody significantly inhibited HSYA-induced HUVEC tube formation and migration. In vivo, the recovery of perfusion of ischemic hindlimb tissue after femoral artery interruption was significantly increased in HSYA-treated mice compared to vehicle controls. Consistent with these results, the arteriole and capillary densities in ischemic gastrocnemius muscles were significantly increased in HSYA-treated mice. Conclusions: These results indicate the potential utility of HSYA for the treatment of ischemic diseases. [ABSTRACT FROM AUTHOR]

To assess the role of angiopoietin (Ang)-1 and Ang-2 and to investigate the clinical significance of serum levels of them in systemic juvenile idiopathic arthritis (s-JIA)-associated macrophage activation syndrome (MAS), we determined these levels in 51 patients with s-JIA, 11 patients with polyarticular JIA (poly-JIA), 12 patients with virus associated hemophagocytic syndrome (VAHS), 12 patients with Kawasaki disease (KD), and 15 age-matched healthy controls (HC). The results were compared with clinical features of MAS. During the MAS phase, serum Ang-1 levels were significantly decreased compared with those during the active and inactive phases. Serum Ang-2/1 ratio were significantly elevated during the MAS phase, compared with those during the active and inactive phases. There was a rapid increase in the Ang-2/1 ratio at the onset of MAS. Serum Ang-1 and the Ang-2/1 ratio significantly correlated with measures of disease activity, including AST and LDH. Ang-2/1 dysregulation was also observed in patients with VAHS, whereas not observed in most cases of KD. The homeostasis of vascular endothelial function by Ang-1 and Ang-2 is disrupted in MAS. Serum Ang-1 levels and the Ang-2/1 ratio might represent promising indicators of disease activity for MAS. [ABSTRACT FROM AUTHOR]

Stroke is a devastating neurological disease with no satisfactory therapies to preserve long-term neurological function, perhaps due to the sole emphasis on neuronal survival in most preclinical studies. Recent studies have revealed the importance of protecting multiple cell types in the injured brain, such as oligodendrocytes and components of the neurovascular unit, before long-lasting recovery of function can be achieved. For example, revascularization in the ischemic penumbra is critical to provide various neurotrophic factors that enhance the survival and activity of neurons and other progenitor cells, such as oligodendrocyte precursor cells. In the present study, we hypothesized that chronic dietary supplementation with fish oil promotes post-stroke angiogenesis, neurogenesis, and oligodendrogenesis, thereby leading to long-term functional improvements. Mice received dietary supplementation with n-3 PUFA-enriched fish oil for three months before and up to one month after stroke. As expected, dietary n-3 PUFAs significantly increased levels of n-3 PUFAs in the brain and improved long-term behavioral outcomes after cerebral ischemia. n-3 PUFAs also robustly improved revascularization and angiogenesis and boosted the survival of NeuN/BrdU labeled newborn neurons up to 35 days after stroke injury. Furthermore, these pro-neurogenic effects were accompanied by robust oligodendrogenesis. Thus, this is the first study to demonstrate that chronic dietary intake of n-3 PUFAs is an effective prophylactic measure not only to protect against ischemic injury for the long term but also to actively promote neurovascular restorative dynamics and brain repair. [ABSTRACT FROM AUTHOR]

Asthma is characterized by chronic airway inflammation that is associated with structural changes termed airway remodeling. Recently, cytokines/mediators that augment inflammation have been attracting attention in this field. The aim of this study was to evaluate serum angiopoietin (Ang)-1, Ang-2, vascular endothelial growth factor (VEGF), and tumor necrosis factor (TNF) alpha values, which have important roles in inflammation, angiogenesis, and remodeling in asthmatic children. We also documented correlations between demographic features, duration of asthma, and pulmonary function test (PFT) parameters. Randomly selected 40 children (20 male and 20 female children, aged 6-16 years) with mild or moderate persistent asthma and 32 healthy children (15 male and 17 female children, aged 6-16 years) enrolled in the study. All asthmatic children had been using inhaled corticosteroids at least for the last 3 months. Serum Ang-1 levels were significantly lower in asthmatic children than those in normal controls. The Ang-1/Ang-2 ratio was also significantly lower in asthmatic children compared with those in normal controls (p < 0.01). However, serum Ang-2, VEGF, and TNF-alpha levels were similar in the two groups. A significant positive correlation was found between VEGF and duration of asthma. No correlation between serum Ang-1, Ang-2, VEGF values, and PFT parameters was obtained. On the other hand, significant negative correlation was detected between serum TNF-alpha and forced expiratory volume in 1 second. We have shown that serum Ang-1 levels and Ang-1/Ang-2 ratio were significantly reduced and balance was toward Ang-2 in asthmatics children. This process may lead to inflammation, destabilization of blood vessels, and trigger remodeling. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7-associated hemolytic-uremic syndrome (HUS) is characterized by profound prothrombotic abnormalities. Endothelial dysfunction, manifested as dysregulation of angiopoietins 1 and 2 (Ang-1/2), could underlie HUS pathophysiology. We measured Ang-1/2 in 77 children with E. coli O157:H7 infection. Ang-1, Ang-2, and the Ang-2/Ang-1 ratio were significantly different in HUS vs the pre-HUS phase of illness or uncomplicated infection. Angiopoietin dysregulation preceded HUS and worsened as HUS developed. In vitro exposure of human microvascular endothelial cells to Shiga toxin recapitulated the in vivo observations. Angiopoietin regulation is profoundly affected before and during HUS, reflecting that subclinical endothelial dysfunction precedes overt microangiopathy. [ABSTRACT FROM PUBLISHER]

Background & Aims: Sphingosine kinase (SphK)/sphingosine 1-phosphate (S1P)/S1P receptor (S1PR) axis is involved in multiple biological processes, including liver fibrosis. Angiogenesis is an important pathophysiological process closely associated with liver fibrosis; however, the functional role of SphK/S1P/S1PR in this process remains incompletely defined. Methods: Bile duct ligation or carbon tetrachloride was used to induce liver fibrosis in mice. Human fibrotic samples were obtained from livers of patients undergoing liver transplantation. S1P levels in the liver were examined by HPLC. Expression of angiogenic markers, including angiopoietin 1, CD31, vascular cell adhesion molecule-1, and von Willebrand factor, was characterized by immunofluorescence, real-time RT-PCR, and Western blot in the fibrotic liver and primary mouse hepatic stellate cells (HSCs). SphK inhibitor (SKI) or S1PR antagonists were administered intraperitoneally in mice. Results: S1P levels in the liver were closely correlated with mRNA expression of angiogenic markers. Ang1 is expressed in activated HSCs of the fibrotic liver and in primary HSCs. In HSCs, by using specific antagonists or siRNAs, we demonstrated S1P stimulation induced Ang1 expression via S1PR1 and S1PR3. In vivo, S1P reduction by SKI inhibited angiogenesis in fibrotic mice. Furthermore, S1PR1/3 antagonist significantly blocked upregulation of angiogenic markers in the injured liver, and attenuated the extent of liver fibrosis, while S1PR2 antagonist had no effect on angiogenesis, supporting the key role of S1PR1 and S1PR3 in angiogenesis underlying liver fibrosis process. Conclusions: SphK1/S1P/S1PR1/3 axis plays a crucial role in the angiogenic process required for fibrosis development, which may represent an effective therapeutic strategy for liver fibrosis. [Copyright &y& Elsevier]

Background/Aims: The recovery process from renal injury in hemolytic uremic syndrome (HUS) remains obscure. In order to clarify the role of vascular endothelial growth factor (VEGF) and angiopoietin 1 (Ang-1) in the renal recovery from HUS, we produced a model of mild HUS and examined the renal recovery process. Methods: We investigated three groups of mice. Group 1 consisted of mice that received an injection of Shiga toxin 2 (Stx2) and lipopolysaccharide (LPS); group 2 consisted of mice that received an injection of low dose of Stx2 and LPS, and group 3 consisted of control mice. Results: Serum Cr levels in group 1 were greater than those in group 2, and all mice in group 1 died, whereas all mice in group 2 remained alive. Endothelial injury at 24 h in group 1 was higher than in group 2. Electron-microscopic findings demonstrated that the endothelial cells formed immature capillary-like lumina from 7 to 28 days with increases in the expression of CD31-positive cells. Glomerular VEGF expression decreased at 72 h in group 1, but gradually increased in group 2. Glomerular Ang-1 expression peaked from 72 h to 28 days. Ang-1 expression was frequently found in the endothelial cell region of vesicle walls simultaneous with increased CD31-positive staining. Conclusion: Our findings suggest that VEGF and Ang-1 play important roles in the recovery process, particularly in the regeneration of endothelial injury. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: To determine the concentrations of angiopoietin 1 (ANGPT1) and ANGPT2 in individual human preovulatory follicles in relation to their diameter or volume to clarify the role of these molecules in folliculogenesis. Design: Prospective study. Setting: Research laboratory at Kansai Medical University, Osaka, Japan. Patient(s): Twenty-three women undergoing IVF. Intervention(s): On the day of oocyte retrieval, serum samples and follicular fluid (FF) from individual follicles were collected. We analyzed 348 follicles. Main Outcome Measure(s): ANGPT1 and ANGPT2 concentrations in FF and serum and oocyte recovery rates. Result(s): On average, ANGPT1 concentrations in FF were 150 times lower than those in serum, whereas ANGPT2 concentrations in FF were 8 times higher than those in serum. The concentrations of ANGPT1 in follicles with a diameter ≤17 mm were significantly higher than those in follicles with a diameter ≥18 mm. On the other hand, the concentrations of ANGPT2 in follicles with a diameter ≤17 mm were significantly lower than those in follicles with a diameter ≥18 mm. The ANGPT2/ANGPT1 ratio increased with enlargement of follicular diameter. ANGPT1 concentrations in FF decreased with follicular volume. ANGPT2 concentrations and the ANGPT2/ANGPT1 ratio in FF rose with follicular volume. The ANGPT2/ANGPT1 ratio in FF from the oocyte recovery group was significantly higher than that from the nonrecovery group. Conclusion(s): Our data suggested that the change in ANGPT1 and ANGPT2 levels may be associated with follicular growth and angiogenesis during the preovulatory period. [Copyright &y& Elsevier]

Background: Methotrexate (MTX) is a very effective treatment for chronic inflammatory diseases, which are often associated with increased angiogenesis. Angiogenesis is dependent on a perfectly coordinated balance between endogenous-positive and -negative regulatory factors, including vascular endothelial growth factor (VEGF) and the angiopoietins (Ang). The aim of this study was to investigate the effects of MTX on levels of VEGF, Ang-1, and Ang-2 in organ-cultured nasal polyps (NPs). Methods: To determine the effects of MTX, NP tissues were cultured using an air-liquid interface method. Cultures were maintained in the absence or presence of MTX (10 or 100 micromoles) for 24 hours. Hematoxylin and eosin, and TUNEL (terminal deoxynucleotidyl transferase [Tdt]-mediated dUTP-biotin nick-end labeling) staining were performed to observe apoptosis. Enzyme-linked immunosorbent assay was used to quantify tissue concentrations of VEGF, Ang-1, and Ang-2. Results: MTX treatment resulted in marked alterations in inflammatory cells, especially eosinophils. In contrast, the mucosal epithelium, microvessels including arterioles, veins and capillaries, and fibroblasts maintained their structure. TUNEL+ cells (apoptotic cells) were seen in the MTX-treated specimens. The more induction of TUNEL+ cells was observed 100-micromolar MTX-treated specimens. VEGF and Ang-1 levels were significantly lower, and Ang-2 levels were significantly higher in NPs treated with 100-micromolar MTX than in nontreated NPs (p < 0.01). Conclusion: MTX may inhibit the growth of NPs via local regulation of VEGF, Ang-1, and Ang-2 protein levels. We suggest that MTX can be used to treat NPs. [ABSTRACT FROM AUTHOR]

Objective: To examine the effects of intraventricular pre-treatment with a combination of recombinant adeno-associated virus vectors encoding VEGF (rAAV-VEGF) and Ang1 (rAAV-Ang1) on early stroke in a rat model of transient middle cerebral artery occlusion (tMCAO). Methods: rAAV-VEGF/rAAV-Ang1 or rAAV-VEGF/rAAV-null vector was delivered into the lateral ventricles of 48 rats. Eight weeks later, the rats were subjected to tMCAO for 2 hours. During the early stages of ischemic reperfusion, VEGF and Ang1 expression levels, blood–brain barrier (BBB) permeability and cerebral microvessel density were determined and compared statistically between groups. Cerebral infarct volume and modified neurological severity scores (NSS) were also determined to evaluate the therapeutic efficacy of rAAV-VEGF/rAAV-Ang1. Results: Intraventricular application of rAAV-VEGF/rAAV-Ang1, 8 weeks before tMCAO, resulted in VEGF and Ang1 overexpression, and significantly decreased Evans blue permeability following ischemia (p<0.05). The microvessel density in the peri-infarct zone was significantly increased in the rAAV-VEGF/rAAV-Ang1 group compared with the rAAV-VEGF/rAAV-null group (p<0.05). Cerebral infarct volume and NSS in the rAAV-VEGF/rAAV-Ang1 group were significantly decreased compared with the rAAV-VEGF/rAAV-null group (p<0.05). Conclusion: In cerebral ischemia, the combination of Ang1 and VEGF could be used early to promote the formation of mature neovessels and protect the injured cells, without inducing the side effects on BBB permeability. Early intraventricular injection of mixed rAAV-VEGF and rAAV-Ang1 may be a favorable therapeutic strategy in gene therapy for experimental stroke. [ABSTRACT FROM AUTHOR]

In this study, we tested the hypothesis that the Angiopoietin 1 (Ang1)/Tie2 pathway mediates simvastatin-induced vascular integrity and migration of neuroblasts after stroke. Rats were subjected to 2 hrs of middle cerebral artery occlusion (MCAo) and treated, starting 1 day after stroke with or without simvastatin (1 mg/kg, daily) for 7 days. Simvastatin treatment significantly decreased blood–brain barrier (BBB) leakage and concomitantly, increased Ang1, Tie2 and Occludin expression in the ischaemic border (IBZ) compared to the MCAo control group. Simvastatin also significantly increased doublecortin (DCX, a marker of migrating neuroblasts) expression in the IBZ compared to control MCAo rats. DCX was highly expressed around vessels. To further investigate the signalling pathway of simvastatin-induced vascular stabilization and angiogenesis, rat brain microvascular endothelial cell (RBMEC) culture was employed. The data show that simvastatin treatment of RBMEC increased Ang1 and Tie2 gene and protein expression and promoted phosphorylated-Tie2 activity. Simvastatin significantly increased endothelial capillary tube formation, an index of angiogenesis, compared to non-treated control. Inhibition of Ang1 or knockdown of Tie2 gene expression in endothelial cells significantly attenuated simvastatin-induced capillary tube formation. In addition, simvastatin significantly increased subventricular zone (SVZ) explant cell migration compared to non-treatment control. Inhibition of Ang1 significantly attenuated simvastatin-induced SVZ cell migration. Simvastatin treatment of stroke increases Ang1/Tie2 expression and thereby reduces BBB leakage and promotes vascular stabilization. Ang1/Tie2 expression induced by simvastatin treatment promotes neuroblast micro-vascular coupling after stroke. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: To determine the roles of vascular endothelial growth factor (VEGF), Angiopoietin (Ang)-1, and Ang-2 in nasal polyps (NPs) by assaying expression patterns and evaluating the effects of dexamethasone (DEX) on these factors in organ cultured NPs. Study Design: Prospective. Methods: Expression patterns of VEGF, Ang-1, and Ang-2 in NPs were compared with those in inferior turbinate mucosa samples. Tissue samples were analyzed using the enzyme-linked immunosorbent assay (ELISA) and immunofluorescent staining methods. To determine the effects of DEX, NP tissues were cultured using an air-liquid interface method. Cultures were maintained in the absence or presence of DEX (10 μM or 100 μM) for 24 hours, and tissue samples analyzed with ELISA. Results: VEGF and Ang-1 levels were significantly higher, whereas the Ang-2 level was significantly lower in NPs, compared to inferior turbinate mucosa ( P < .05). In NPs, VEGF and Ang-1 were detected in glandular epithelial, vascular endothelial, as well as stromal inflammatory cells, whereas Ang-2 was detected only in stromal inflammatory cells. VEGF and Ang-1 levels were significantly lower, while Ang-2 levels were significantly higher in 100 μM DEX-treated group than nontreated group ( P < .01). Conclusions: Imbalance among VEGF, Ang 1, and Ang 2 may be important in the angiogenesis of NPs. Moreover, DEX can control the expression of these factors in NPs. We suggest that VEGF and Ang-1 act as positive regulatory factors, and Ang-2 functions as a negative regulatory factor of angiogenesis in NPs. Laryngoscope, 2009 [ABSTRACT FROM AUTHOR]

Abstract: Although osteoblasts express the angiogenic protein Angiopoietin 1 (Ang1), the role of Ang1 in bone formation remains largely unknown. Here we report that Ang1 overexpression in osteoblasts driven by the osteoblast-specific 2.3kb alpha 1 type 1 collagen promoter results in increased bone mass in vivo. In Ang1-transgenic mice (Ang1-Tg), bone volume and bone parameters increased significantly compared with wild-type littermates, although the Ang1 receptor, Tie2 was not expressed in osteoblasts. Tie2 is primarily expressed in vascular endothelial cells, and Ang1-Tie2 signaling is reportedly crucial for angiogenesis. We found that the number of vascular endothelial cells was significantly elevated in Ang1-Tg mice compared with that of wild-type littermates, an increase accompanied by increased alkaline-phosphatase activity, a marker of osteoblast activation. The number of osteoclasts in the bone of Ang1-Tg mice did not differ from wild-type littermates. These results indicate that angiogenesis induced by Ang1 expressed in osteoblasts is coupled with osteogenesis. [Copyright &y& Elsevier]

Abstract: Signal transduction pathways leading to angiopoietin 1 (Ang1)-induced capillary morphogenesis by endothelial cells remain poorly defined. Angiogenic cellular responses by endothelial cells may be modulated in vivo by chronic hypoxia, such as that induced by tumors. Here, we studied Ang1-induced capillary morphogenesis in human umbilical-vein endothelial cells (HUVECs) cultured chronically under normoxic (21% oxygen) or hypoxic (1.5% oxygen) conditions. Downregulation of Src using a small interfering RNA (siRNA) inhibited Ang1-induced capillary morphogenesis of HUVECs cultured under both conditions by blocking cell spreading and protrusion. Ang1 upregulated the Src-dependent secretion of vascular endothelial growth factor-A (VEGF-A). Blockade of endogenous VEGF-A also inhibited Ang1-induced capillary morphogenesis. Addition of exogenous VEGF-A restored cell spreading and protrusion, leading to Ang1-induced capillary morphogenesis of Src siRNA-treated HUVECs, suggesting that Ang1-induced VEGF-A secretion through Src was required for capillary morphogenesis. PP2 inhibited both Ang1-induced capillary morphogenesis and Src activation in HUVECs cultured under normoxic conditions, but the PP2 activity was significantly impaired in HUVECs cultured under hypoxic conditions. Expression of multidrug resistance-associated protein 1 (MRP 1) was upregulated in hypoxic HUVECs, and treatment with MRP 1 siRNA restored the inhibitory action of PP2. Taken together, our results suggest that Ang1 induces capillary morphogenesis in HUVECs through Src-dependent upregulation of endogenous VEGF-A. Conditions of chronic hypoxia impaired the effect of PP2, possibly via MRP 1. [Copyright &y& Elsevier]

Abstract: Pericytes occur in tumour blood vessels and are critical for the development of a functional vascular network. Targeting tumour pericytes is a promising anti-angiogenic therapy but requires identifying the mechanisms of their recruitment in tumour and addressing whether these mechanisms can be selectively harnessed. Among the pathways involved in pericyte recruitment during embryonic development, the contribution of platelet-derived growth factor B and sphingosine 1-phosphate is confirmed in tumour angiogenesis. The effect of angiopoietin 1 depends on the tumour model. Transforming growth factor-β1 enhances tumour vascularization and microvessel maturation. Recent reports suggest a participation of matrix metalloproteinases (MMP) in tumour pericyte recruitment that is consistent with the effect of certain MMPs in the development of microvasculature in embryonic development and in in vitro models of vascular remodelling. Here, we discuss the possibility for MMPs to contribute to pericyte recruitment at six levels: (1) direct promotion of pericyte invasion by extracellular matrix degradation; (2) stimulation of pericyte proliferation and protection against apoptosis by modification of the ECM; (3) activation of pericytes through the release of growth factor bound to the ECM; (4) transactivation of angiogenic cell surface receptor; (5) propagation of angiogenic signalling as cofactor; and (6) recruitment of bone marrow-derived stem cells. [Copyright &y& Elsevier]