Pro-angiogenic Vascular Endothelial Growth Factor Research Articles

Is the Long‐term Impact of a Multidomain Lifestyle Intervention on Cognitive Function Mediated by Changes in Leptin and Vascular Endothelial Growth Factor Concentrations?

AbstractBackgroundThe 10‐year intensive lifestyle intervention (ILI) of the Look AHEAD study resulted in a legacy of relative deficits in cognitive function among participants who entered the clinical trial with a history of cardiovascular disease or current obesity, as compared to participants assigned to the diabetes support and education (DSE) intervention. We hypothesized that levels of two weight‐sensitive proangiogenic cytokines, leptin and vascular endothelial growth factor (VEGF), which have been previously reported to be associated with cognitive function, may have been altered by the ILI and account for this concerning finding.MethodConcentrations of leptin and VEGF were determined using stored serum collected from 1,279 participants at Look AHEAD baseline, proximal to cessation of the intervention (Epoch 1), and an average of 4 years later (Epoch 2). Masked clinic staff conducted up to four standardized assessments of cognitive function at times ranging from 8 to 18 years after baseline. A composite score was derived from tests of attention, executive function, and memory. Mixed effects models were used to assess relative differences in leptin and VEGF concentrations between intervention groups and whether these accounted for changes in cognitive composite scores, overall and within subgroups defined by baseline history of cardiovascular disease or obesity.ResultIn both intervention groups, leptin concentrations increased from baseline to Epoch 1, and further between Epochs 1 and 2 (p<0.001). VEGF concentrations decreased between enrollment and Epoch 2 in both groups, and decreased substantially more between Epoch 1 and 2 in ILI than in DSE (p = 0.04). Overall, there was little evidence that leptin and VEGF concentrations were related to cognitive functioning. ILI‐DSE differences in VEGF, but not leptin, concentrations varied depending on baseline history of cardiovascular disease and obesity, but neither leptin or VEGF concentrations accounted for the relative decrements in cognitive function evident during long‐term follow‐up in participants assigned to ILI.ConclusionAmong persons with type 2 diabetes and either a history of cardiovascular disease or obesity, long‐term relative deficits in cognitive function associated with intensive lifestyle intervention are not related to differences in two weight‐sensitive proangiogenic cytokines.

Indole-3-Carbinol Inhibits the Growth of Endometriotic Lesions by Suppression of Microvascular Network Formation.

Endometriosis represents an estrogen-dependent disorder with a complex pathophysiology. Phytochemicals are promising candidates for endometriosis therapy, because they simultaneously target different cellular processes involved in the pathogenesis of endometriosis. Herein, we analyzed whether indole-3-carbinol (I3C) suppresses the development of endometriotic lesions, which were surgically induced by fixation of uterine tissue samples (diameter: 2 mm) from female BALB/c donor mice to the peritoneum of recipient animals. The mice received either I3C or vehicle (control) by peroral administration once per day. Growth, cyst formation, cell proliferation, microvascularization and protein expression of the lesions were assessed by high-resolution ultrasound imaging, caliper measurements, histology, immunohistochemistry and Western blotting. I3C inhibited the vascularization and growth of endometriotic lesions without inducing anti-angiogenic and anti-proliferative side effects on reproductive organs. This was associated with a significantly reduced number of proliferating stromal and endothelial cells and a lower expression of the pro-angiogenic signaling molecules vascular endothelial growth factor receptor-2 (VEGFR2), phosphoinositide 3-kinase (PI3K) and phosphorylated extracellular signal-regulated kinase (pERK) within I3C-treated lesions when compared to controls. These findings indicate that I3C effectively inhibits endometriotic lesion formation in mice. Thus, further studies should clarify whether I3C may be also beneficial for the prevention and therapy of the human disease.

Antineoplastic agents in chemotherapy facilitating tumor growth and angiogenesis in the interval administrations

AimsThere is emerging evidence that antineoplastic agents and the cytotoxic effects on tumor tissues attenuate the benefits of chemotherapy due to tumor microenvironment changes. Nevertheless, the actual relationship between chemotherapy and recurrent tumors in which the genotypes differ from the original tumor after chemotherapy is unclear. Materials and methodsBone marrow transplantation, flow cytometer, immune inhibition and immunofluorescence will be utilized to investigate the effect of antineoplastic agents on bone-marrow-derived cells (BMDCs) release and recruitment, and to explore the pathways and mechanisms of antineoplastic agents in promoting tumor growth. Key findingsTumor growth and angiogenesis were significantly enhanced in the mouse model after treatment with antineoplastic agents such as cyclophosphamide, 5-fluorouracil, or cisplatin, along with large increases in proangiogenic vascular endothelial growth factor receptor-2 (VEGFR2+), β3+, CD11b+Gr-1+, and VEGFR2+β3+ BMDCs in circulating blood. BMDC recruitment and VEGFR2 and β3 mRNA transcription in tumor tissues were also enhanced by antineoplastic agents. Antineoplastic-agent-treated BMDCs markedly augmented tumor and endothelial cell proliferation, and β3 mRNA transcription in endothelial cells (ECs). SignificanceThe results suggested that antineoplastic-agent treatment augmented the tumor microenvironment by mobilizing proangiogenic BMDCs, enhancing BMDC recruitment and angiogenesis, and increasing BMDC-mediated tumor and EC functions. These results led to tumor growth and angiogenesis aggravation. It is paramount to elucidate the potential mechanism by which the cellular and molecular effects triggered by the antineoplastic agents attenuate the effects of cancer therapy, and thereafter to explore possible methods for improving tumor treatment efficacy.

Evaluation of Angiogenesis in an Acellular Porous Biomaterial Based on Polyhydroxybutyrate and Chitosan Using the Chicken Ex Ovo Chorioallantoic Membrane Model.

Simple SummaryThe chorioallantoic membrane (CAM) is an avian extraembryonic membrane widely used as an experimental assay to study angiogenesis and its inhibition in response to tissues, cells, or soluble factors. In recent years, the CAM has become popular in scientific studies focused on the use of its potential for the study of biocompatibility of materials for regenerative strategies and tissue engineering applications. Great research efforts are being made to develop innovative biomaterials able to treat hard tissue defects, including diseases such as a bone cancer. In this article, we describe an approach to detect the formation of blood vessels inside the porous acellular biopolymer polyhydroxybutyrate/chitosan (PHB/CHIT) scaffold using the CAM assay as an in vivo alternative animal model, including macroscopic, histological, immunohistochemical, and molecular evaluation of the biocompatibility.The chorioallantoic membrane (CAM) is a highly vascularized avian extraembryonic membrane widely used as an in vivo model to study angiogenesis and its inhibition in response to tissues, cells, or soluble factors. In recent years, the use of CAM has become an integral part of the biocompatibility testing process for developing biomaterials intended for regenerative strategies and tissue engineering applications. In this study, we used the chicken ex ovo CAM assay to investigate the angiogenic potential of innovative acellular biopolymer polyhydroxybutyrate/chitosan (PHB/CHIT) scaffold, which is intended for the treatment of hard tissue defects, depending on treatment with pro- and anti-angiogenic substances. On embryonic day (ED) 7, the experimental biomaterials were placed on the CAM alone or soaked in vascular endothelial growth factor (VEGF-A), saline solution (PHY), or tyrosine kinase inhibitor (SU5402). After 72 h, the formation of vessels was analyzed in the surrounding area of the scaffold and inside the pores of the implants, using markers of embryonic endothelium (WGA, SNA), myofibroblasts (α-SMA), and macrophages (KUL-01). The morphological and histochemical analysis showed strong angiogenic potential of untreated scaffolds without additional effect of the angiogenic factor, VEGF-A. The lowest angiogenic potential was observed in scaffolds soaked with SU5402. Gene expression of pro-angiogenic growth factors, i.e., VEGF-A, ANG-2, and VE-CAD, was upregulated in untreated scaffolds after 72 h, indicating a pro-angiogenic environment. We concluded that the PHB/CHIT has a strong endogenous angiogenic potential and could be promising biomaterial for the treatment of hard tissue defects.

Spontaneous Browning of White Adipose Tissue Improves Angiogenesis and Reduces Macrophage Infiltration After Fat Grafting in Mice.

Background: Fat grafting is a frequently used technique; however, its survival/ regeneration mechanism is not fully understood. The browning of white adipocytes, a process initiated in response to external stimuli, is the conversion of white to beige adipocytes. The physiologic significance of the browning of adipocytes following transplantation is unclear. Methods: C57BL/6 mice received 150 mg grafts of inguinal adipose tissue, and then the transplanted fat was harvested and analyzed at different time points to assess the browning process. To verify the role of browning of adipocytes in fat grafting, the recipient mice were allocated to three groups, which were administered CL316243 or SR59230A to stimulate or suppress browning, respectively, or a control group after transplantation. Results: Browning of the grafts was present in the center of each as early as 7 days post-transplantation. The number of beige cells peaked at day 14 and then decreased gradually until they were almost absent at day 90. The activation of browning resulted in superior angiogenesis, higher expression of the pro-angiogenic molecules vascular endothelial growth factor A (VEGF-A) and fibroblast growth factor 21 (FGF21), fewer macrophages, and ultimately better graft survival (Upregulation, 59.17% ± 6.64% vs. Control, 40.33% ± 4.03%, *p < 0.05), whereas the inhibition of browning led to poor angiogenesis, lower expression of VEGF-A, increased inflammatory macrophages, and poor transplant retention at week 10 (Downregulation, 20.67% ± 3.69% vs. Control, 40.33% ± 4.03%, *p < 0.05). Conclusion: The browning of WAT following transplantation improves the survival of fat grafts by the promotion of angiogenesis and reducing macrophage.

Tissue Kallikrein Protects Rat Prostate against the Inflammatory Damage in a Chronic Autoimmune Prostatitis Model via Restoring Endothelial Function in a Bradykinin Receptor B2-Dependent Way.

Objective The aim of this study was to investigate whether tissue kallikrein (KLK1) can protect the prostate from inflammatory damage and the mechanism involved in it. Methods A total of 50 male Wistar rats were used in this study. Initially, 20 rats were sacrificed to obtain the prostate antigen to induce experimental autoimmune prostatitis (EAP), and the remaining 30 rats were randomly divided into 5 experimental groups (normal control group (NC group), NC+KLK1 group (NCK group), EAP group, EAP+KLK1 group (EAPK group), and EAP+KLK1+HOE140 group (EAPKH group); n = 6). It should be explained that KLK1 mainly exerts its biological effects through bradykinin, and HOE140 is a potent and selective bradykinin receptor B2 (BDKRB2) antagonist. EAP was induced by intradermal injection of 15 mg/ml prostate antigen and complete Freund's adjuvant on days 0, 14, and 28. KLK1 was injected via tail vein at a dose of 1.5 × 10−3 PAN U/kg once a day, and HOE140 was administered by intraperitoneal injection at 20 μg/kg once every two days. Rats were sacrificed on day 42. The RNA and protein of the rat prostate were extracted to analyze the expression differences of KLK1, as well as the inflammation-, fibrosis-, and oxidative stress-related genes. The inflammatory cell infiltration and microvessel density of the prostate were also analyzed by pathological examination. In addition, pathological analysis was performed on prostate samples from patients undergoing benign prostate hyperplasia (BPH) surgery. Results The expression of KLK1 in the prostate decreased in the EAP group as well as BPH patients with obvious inflammation. KLK1 administration significantly inhibited inflammatory cell infiltration and reduced the production of inflammatory cytokines in the EAPK group. Prostate samples from the EAP group showed increased infiltration of T cells and macrophages, as well as gland atrophy, hypoxia, fibrosis, and angiogenesis. KLK1 administration upregulated endothelial nitric oxide synthase (eNOS) expression and suppressed oxidative stress, as well as transforming growth factor β1 (TGF-β) signaling pathways and the proangiogenic vascular endothelial growth factor (VEGF) in the EAPK group. However, in the EAPKH group in which HOE140 blocked BDKRB2, the beneficial effects of KLK1 were all cancelled. In addition, KLK1 intervention in normal rats had no obvious side effects. Conclusion The KLK1 expression is inhibited in the inflamed prostates of humans and rats. Exogenous KLK1 restored endothelial function via a BDKRB2-dependent way and then played a role in improving microcirculation and exerted anti-inflammatory, antifibrotic, and antioxidative stress effects in the rat chronic-inflamed prostate.

Extracellular HSP90α Induces MyD88-IRAK Complex-Associated IKKα/β−NF-κB/IRF3 and JAK2/TYK2−STAT-3 Signaling in Macrophages for Tumor-Promoting M2-Polarization

M2-polarization and the tumoricidal to tumor-promoting transition are commonly observed with tumor-infiltrating macrophages after interplay with cancer cells or/and other stroma cells. Our previous study indicated that macrophage M2-polarization can be induced by extracellular HSP90α (eHSP90α) secreted from endothelial-to-mesenchymal transition-derived cancer-associated fibroblasts. To extend the finding, we herein validated that eHSP90α-induced M2-polarized macrophages exhibited a tumor-promoting activity and the promoted tumor tissues had significant increases in microvascular density but decreases in CD4+ T-cell level. We further investigated the signaling pathways occurring in eHSP90α-stimulated macrophages. When macrophages were exposed to eHSP90α, CD91 and toll-like receptor 4 (TLR4) functioned as the receptor/co-receptor for eHSP90α binding to recruit interleukin (IL)-1 receptor-associated kinases (IRAKs) and myeloid differentiation factor 88 (MyD88), and next elicited a canonical CD91/MyD88–IRAK1/4–IκB kinase α/β (IKKα/β)–nuclear factor-κB (NF-κB)/interferon regulatory factor 3 (IRF3) signaling pathway. Despite TLR4-MyD88 complex-associated activations of IKKα/β, NF-κB and IRF3 being well-known as involved in macrophage M1-activation, our results demonstrated that the CD91-TLR4-MyD88 complex-associated IRAK1/4−IKKα/β−NF-κB/IRF3 pathway was not only directly involved in M2-associated CD163, CD204, and IL-10 gene expressions but also required for downregulation of M1 inflammatory cytokines. Additionally, Janus kinase 2 (JAK2) and tyrosine kinase 2 (TYK2) were recruited onto MyD88 to induce the phosphorylation and activation of the transcription factor signal transducer and activator of transcription-3 (STAT-3). The JAK2/TYK2−STAT-3 signaling is known to associate with tumor promotion. In this study, the MyD88−JAK2/TYK2−STAT-3 pathway was demonstrated to contribute to eHSP90α-induced macrophage M2-polarization by regulating the expressions of M1- and M2-related genes, proangiogenic protein vascular endothelial growth factor, and phagocytosis-interfering factor Sec22b.

Сучасні погляди на молекулярні та судинні механізми розвитку прееклампсії

у статті узагальнено аргументи та контраргументи в рамках наукової дискусії щодо питання механізмів розвитку прееклампсії. Основна мета цього дослідження це узагальнення інформації про молекулярні та судинні механізми прееклампсії. Завдяки детальному вивченню літературних джерел, їхній систематизації та підходів до вирішення проблеми, було виявлено, що генетичні та фактори навколишнього середовища викликають дезадаптацію плаценти, що призводить до дефектної плацентації, апоптозу інвазивних цитотрофобластів, неадекватного експансивного ремоделювання спіральних артерій та плацентарного тиску. Актуальність дослідження даної патології полягає в тому, що вона багато в чому визначає перинатальну та материнську захворюваність. Однак, на сьогодні немає чіткого уявлення про особливості молекулярних та судинних механізмів прееклампсії, тому це призводить до суперечностей у лікуванні таких вагітних жінок, що перешкоджає своєчасному, адекватному лікуванню та профілактиці. Було використано бібліосемантичний метод та контент-аналіз літератури відносно питань нових досліджень по особливостям механізмів розвитку прееклампсії. В статті представлено результати досліджень, які засвідчили, що плацентарна ішемія сприяє вивільненню біоактивних факторів у материнський кровообіг, викликаючи дисбаланс між антиангіогенною розчинною тирозинкіназою-1, розчинним ендогліном та проангіогенним судинним ендотеліальним фактором росту, фактором росту плаценти та трансформуючим фактором росту B. Плацентарна ішемія також стимулює вивільнення прозапальних цитокінів, фактору, що індукує гіпоксію, активних форм кисню та агоністичних аутоантитіл до рецепторів ангіотензину 1 типу. Ці циркулюючі фактори націлені на ендотелій судин, викликаючи генералізований ендотеліоз у системних, ниркових, церебральних та печінкових судинах і призводять до зменшення судинних розширювачів, таких як оксид азоту, простациклін, фактор гіперполяризації, та збільшення судинозвужувальних засобів, таких як ендотелін-1 та тромбоксан А2. Біоактивні фактори також впливають на гладку мускулатуру судин і посилюють механізми судинного скорочення, включаючи цитозольний Са2+, протеїнкіназу С та Rho-кіназу. Дослідження емпірично підтверджує та теоретично доводить, що подальше розуміння взаємодії між біоактивними факторами, судинними механізмами та молекулярними мішенями повинно допомогти розробити більш ефективні заходи для раннього виявлення та профілактики прееклампсії. Результати проведеного дослідження можуть бути корисними для лікарів первинної ланки, гінекологів, кардіологів, терапевтів.

Exacerbated VEGF up-regulation accompanies diabetes-aggravated hemorrhage in mice after experimental cerebral ischemia and delayed reperfusion

Reperfusion therapy is the preferred treatment for ischemic stroke, but is hindered by its short treatment window, especially in patients with diabetes whose reperfusion after prolonged ischemia is often accompanied by exacerbated hemorrhage. The mechanisms underlying exacerbated hemorrhage are not fully understood. This study aimed to identify this mechanism by inducing prolonged 2-hour transient intraluminal middle cerebral artery occlusion in diabetic Ins2Akita/+ mice to mimic patients with diabetes undergoing delayed mechanical thrombectomy. The results showed that at as early as 2 hours after reperfusion, Ins2Akita/+ mice exhibited rapid development of neurological deficits, increased infarct and hemorrhagic transformation, together with exacerbated down-regulation of tight-junction protein ZO-1 and up-regulation of blood-brain barrier-disrupting matrix metallopeptidase 2 and matrix metallopeptidase 9 when compared with normoglycemic Ins2+/+ mice. This indicated that diabetes led to the rapid compromise of vessel integrity immediately after reperfusion, and consequently earlier death and further aggravation of hemorrhagic transformation 22 hours after reperfusion. This observation was associated with earlier and stronger up-regulation of pro-angiogenic vascular endothelial growth factor (VEGF) and its downstream phospho-Erk1/2 at 2 hours after reperfusion, which was suggestive of premature angiogenesis induced by early VEGF up-regulation, resulting in rapid vessel disintegration in diabetic stroke. Endoplasmic reticulum stress-related pro-apoptotic C/EBP homologous protein was overexpressed in challenged Ins2Akita/+ mice, which suggests that the exacerbated VEGF up-regulation may be caused by overwhelming endoplasmic reticulum stress under diabetic conditions. In conclusion, the results mimicked complications in patients with diabetes undergoing delayed mechanical thrombectomy, and diabetes-induced accelerated VEGF up-regulation is likely to underlie exacerbated hemorrhagic transformation. Thus, suppression of the VEGF pathway could be a potential approach to allow reperfusion therapy in patients with diabetic stroke beyond the current treatment window. Experiments were approved by the Committee on the Use of Live Animals in Teaching and Research of the University of Hong Kong [CULATR 3834-15 (approval date January 5, 2016); 3977-16 (approval date April 13, 2016); and 4666-18 (approval date March 29, 2018)].

Establishment of a Pre-vascularized 3D Lung Cancer Model in Fibrin Gel-Influence of Hypoxia and Cancer-Specific Therapeutics.

Lung cancer is the most frequently diagnosed cancer worldwide and the one that causes the highest mortality. In order to understand the disease and to develop new treatments, in vitro human lung cancer model systems which imitate the physiological conditions is of high significance. In this study, a human 3D lung cancer model was established that features the organization of a tumor with focus on tumor angiogenesis. Vascular networks were formed by co-culture of human umbilical vein endothelial cells and adipose tissue-derived mesenchymal stem cells (ASC) for 14 days in fibrin. A part of the pre-vascularized fibrin gel was replaced by fibrin gel containing lung cancer cells (A549) to form tri-cultures. This 3D cancer model system was cultured under different culture conditions and its behaviour after treatment with different concentrations of tumor-specific therapeutics was evaluated. The evaluation was performed by measurement of metabolic activity, viability, quantification of two-photon laser scanning microscopy and measurement of the proangiogenic factor vascular endothelial growth factor in the supernatant. Hypoxic conditions promoted vascularization compared to normoxic cultured controls in co- and tri-cultures as shown by significantly increased vascular structures, longer structures with a higher area and volume, and secretion of vascular endothelial growth factor. Cancer cells also promoted vascularization. Treatment with 50 µM gefitinib or 50 nM paclitaxel decreased the vascularization significantly. VEGF secretion was only reduced after treatment with gefitinib, while in contrast secretion remained constant during medication with paclitaxel. The findings suggest that the herein described 3D lung cancer model provides a novel platform to investigate the angiogenic potential of cancer cells and its responses to therapeutics. Thus, it can serve as a promising approach for the development and patient-specific pre-selection of anticancer treatment.

Changes in Plasma VEGF and PEDF Levels in Patients with Central Serous Chorioretinopathy.

Background and Objectives: Retinal pigment epitheliopathy and hyperpermeability of choroidal vessels were postulated to be involved in the pathogenesis of central serous chorioretinopathy (CSC). Imbalanced levels of vascular endothelial growth factor (VEGF) and pigment-epithelium–derived factor (PEDF) were previously implicated in the development of chorioretinal diseases characterized by increased vascular permeability. We aimed to compare the plasma levels of proangiogenic VEGF and antiangiogenic PEDF for 26 patients with acute CSC, 26 patients with chronic CSC, and 19 controls. Materials and Methods: VEGF and PEDF levels were measured using a multiplex immunoassay or enzyme-linked immunosorbent assay. Correlations with disease duration were assessed. Results: VEGF levels differed between groups (p = 0.001). They were lower in patients with acute CSC (p = 0.042) and chronic CSC (p = 0.018) than in controls. PEDF levels were similar in all groups. The VEGF-to-PEDF ratio was lower in CSC patients than in controls (p = 0.04). A negative correlation with disease duration was noted only for PEDF levels in the group with chronic CSC (rho = −0.46, p = 0.017). Discussion: Our study confirmed that patients with CSC have imbalanced levels of VEGF and PEDF. This finding may have important implications for the pathogenesis of CSC. VEGF-independent arteriogenesis rather than angiogenesis may underlie vascular abnormalities in these patients.

Estrogen Promotes Resistance to Bevacizumab in Murine Models of NSCLC

IntroductionSubgroup analyses from clinical studies have suggested that among patients with metastatic NSCLC receiving chemotherapy, females may derive less benefit from the addition of the vascular endothelial growth factor (VEGF) monoclonal antibody bevacizumab (BV) than males. This has raised the question of whether estrogen may affect the response to antiangiogenic therapy. MethodsTo address this, we investigated the effects of estrogen on tumor growth, angiogenesis, and the response to BV in human xenograft models of NSCLC. ResultsWe observed that estrogen induced marked resistance to BV, which was accompanied by a 2.3-fold increase in tumor vascular pericyte coverage (p = 0.01) and an up-regulation of proangiogenic factors, VEGF and platelet-derived growth factor-BB. We also investigated the role of infiltrating myeloid cells, a population that has been associated with resistance to anti-VEGF therapies. We observed that estrogen induced a greater than twofold increase (p = 0.001) in the recruitment of tumor-infiltrating myeloid cells and concomitant increases in the myeloid recruitment factors, G-CSF and CXCL1. Blockade of the estrogen receptor pathway using fulvestrant resensitized tumors to VEGF targeting as evidenced by reduced tumor vasculature and an increase in overall survival in our NSCLC xenograft models. ConclusionsCollectively, these data provide evidence that estrogen may promote resistance to VEGF-targeted therapies, potentially by enhancing pericyte coverage and myeloid recruitment, and suggest that estrogen receptor blockade merits further investigation as an approach to enhance the effects of antiangiogenic therapy.

The cancer angiogenesis co-culture assay: In vitro quantification of the angiogenic potential of tumoroids.

The treatment response to anti-angiogenic agents varies among cancer patients and predictive biomarkers are needed to identify patients with resistant cancer or guide the choice of anti-angiogenic treatment. We present "the Cancer Angiogenesis Co-Culture (CACC) assay", an in vitro Functional Precision Medicine assay which enables the study of tumouroid induced angiogenesis. This assay can quantify the ability of a patient-derived tumouroid to induce vascularization by measuring the induction of tube formation in a co-culture of vascular cells and tumoroids established from the primary colorectal tumour or a metastasis. Furthermore, the assay can quantify the sensitivity of patient-derived tumoroids to anti-angiogenic therapies. We observed that tube formation increased in a dose-dependent manner upon treatment with the pro-angiogenic factor vascular endothelial growth factor A (VEGF-A). When investigating the angiogenic potential of tumoroids from 12 patients we found that 9 tumoroid cultures induced a significant increase in tube formation compared to controls without tumoroids. In these 9 angiogenic tumoroid cultures the tube formation could be abolished by treatment with one or more of the investigated anti-angiogenic agents. The 3 non-angiogenic tumoroid cultures secreted VEGF-A but we observed no correlation between the amount of tube formation and tumoroid-secreted VEGF-A. Our data suggests that the CACC assay recapitulates the complexity of tumour angiogenesis, and when clinically verified, could prove a valuable tool to quantify sensitivity towards different anti-angiogenic agents.

Non-invasive Biomarkers of Liver Inflammation and Cell Death in Response to Alcohol Detoxification

IntroductionAlcohol-related liver disease (ALD) represents the most common liver disease worldwide, however, the underlying molecular mechanisms are still poorly understood. Namely centrilobular inflammation and programmed cell death are characteristic to ALD and it remains to be elucidated why they persist despite the absence of alcohol.AimsTo study the effects of alcohol withdrawal in a cohort of heavy drinkers and the role of cirrhosis by using non-invasive biomarkers such as cytokines, apoptotic and angiogenic markers.MethodsCaspase 3-cleaved M30, M65, cytokines (IL-6, IL-8), tumor necrosis factor alpha (TNF-α), transforming growth factor (TGF-β) and vascular endothelial growth factor (VEGF) were measured in 114 heavy drinkers. The role of alcohol detoxification was investigated in 45 patients. The liver histology was available in 23 patients. Fibrosis stage and steatosis were assessed by measuring liver stiffness (LS) and controlled attenuation parameter (CAP) in all patients using transient elastography (FibroScan, Echosens, Paris). Mean observation interval between the measurements was 5.7 ± 1.4 days (mean + –SD).ResultsPatients consumed a mean of 204 ± 148 g/day alcohol with a heavy drinking duration of 15.3 ± 11.0 years. Mean LS was 20.7 ± 24.4 kPa and mean CAP was 303 ± 51 dB/m. Fibrosis distribution was F0–38.1%, F1-2–31%, F3–7.1 and F4–23.9%. Apoptotic markers M30 and M65 were almost five times above normal. In contrast, TNF- α a, IL-8 and VEGF were only slightly elevated. Patients with manifest liver cirrhosis (F4) had significantly higher levels of M30, M65, IL-6 and IL-8. Histology features such as hepatocyte ballooning, Mallory-Denk bodies, inflammation and fibrosis were all significantly associated with elevated LS, and serum levels of TNF-alpha, M30 and M65 but not with CAP and other cytokines. During alcohol detoxification, LS, transaminases, TGF- β, IL-6, IL-8 and VEGF decreased significantly. In contrast, no significant changes were observed for M30, M65 and TNF- α and M30 even increased during detoxification in non-cirrhotic patients. Profibrogenic cytokine TGF-beta and pro-angiogenic cytokine VEGF showed a delayed decrease in patients with manifest cirrhosis.ConclusionPatients with alcohol-related cirrhosis have a pronounced apoptotic activity and a distinct inflammatory response that only partly improves after 1 week of alcohol detoxification. Alcohol withdrawal may represent an important approach to better dissect the underlying mechanisms in the setting of alcohol metabolism.

Systemic Antibiotic and Nonsteroidal Anti-Inflammatory Drug Treatment Decreases the Level of Endogenous Angiogenic Vascular Endothelial Growth Factor in Inflamed Human Periapical Tissues

Vascular endothelial growth factor (VEGF)-induced angiogenesis contributes to inflammatory bone resorption in humans. Widely documented antagonists to resorption include antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs). The purpose of this study was to investigate the effect of these drugs on proangiogenic VEGF levels in periradicular lesions. Periapical tissue biopsies were obtained from 42 patients with chronic periapical periodontitis. VEGF levels were measured using a commercial ELISA kit in patients divided into groups according to treatment: no drugs (control group, n = 25), NSAIDs (n = 7), antibiotics (n = 5), and NSAIDs and antibiotics (n = 5). Reverse transcriptase (RT) reaction was performed in all the samples under analysis. Presence of VEGFA and VEGFB gene expression was assessed using reverse-transcription-polymerase chain reaction (RT-PCR). ELISA analysis indicated that average VEGF levels in tissue samples of patients treated with NSAIDs (6.097 ± 1.930 ng/mL), antibiotics (5.661 ± 2.395 ng/mL), and NSAIDs and antibiotics (7.142 ± 2.601 ng/mL) were significantly lower than in samples of control patients (10.432 ± 4.257 ng/mL, ANOVA p = 0.008). The RT-PCR did not reveal VEGFA gene expression in any of the 42 samples. VEGFB gene expression was found in 26 of 42 samples (69.1%). The use of NSAIDs or antibiotics in patients with exacerbated chronic periodontitis decreases VEGF levels in periapical tissues. Pharmacotherapy may minimize the effects of VEGF on apical periodontitis progression in that way.

Bartonella henselae Persistence within Mesenchymal Stromal Cells Enhances Endothelial Cell Activation and Infectibility That Amplifies the Angiogenic Process.

Some bacterial pathogens can manipulate the angiogenic response, suppressing or inducing it for their own ends. In humans, Bartonella henselae is associated with cat-scratch disease and vasculoproliferative disorders such as bacillary angiomatosis and bacillary peliosis. Although endothelial cells (ECs) support the pathogenesis of B. henselae, the mechanisms by which B. henselae induces EC activation are not completely clear, as well as the possible contributions of other cells recruited at the site of infection. Mesenchymal stromal cells (MSCs) are endowed with angiogenic potential and play a dual role in infections, exerting antimicrobial properties but also acting as a shelter for pathogens. Here, we delved into the role of MSCs as a reservoir of B. henselae and modulator of EC functions. B. henselae readily infected MSCs and survived in perinuclearly bound vacuoles for up to 8 days. Infection enhanced MSC proliferation and the expression of epidermal growth factor receptor (EGFR), Toll-like receptor 2 (TLR2), and nucleotide-binding oligomerization domain-containing protein 1 (NOD1), proteins that are involved in bacterial internalization and cytokine production. Secretome analysis revealed that infected MSCs secreted higher levels of the proangiogenic factors vascular endothelial growth factor (VEGF), fibroblast growth factor 7 (FGF-7), matrix metallopeptidase 9 (MMP-9), placental growth factor (PIGF), serpin E1, thrombospondin 1 (TSP-1), urokinase-type plasminogen activator (uPA), interleukin 6 (IL-6), platelet-derived growth factor D (PDGF-D), chemokine ligand 5 (CCL5), and C-X-C motif chemokine ligand 8 (CXCL8). Supernatants from B. henselae-infected MSCs increased the susceptibility of ECs to B. henselae infection and enhanced EC proliferation, invasion, and reorganization in tube-like structures. Altogether, these results indicate MSCs as a still underestimated niche for persistent B. henselae infection and reveal MSC-EC cross talk that may contribute to exacerbate bacterium-induced angiogenesis and granuloma formation.

An increase in blood levels of vascular endothelial growth factor and highly sensitive C-reactive protein in patients with hypertension and obesity is associated with the left ventricular hypertrophy

Abstract Funding Acknowledgements Type of funding sources: None. Background In patients with essential hypertension (H) in combination with abdominal obesity (АО), there is a more frequent and earlier development of asymptomatic hypertension-mediated organ damage (HMOD). One of the prognostically unfarable HMODs is left ventricular hypertrophy (LVH). According to modern concepts, in the mechanisms of HMOD formation, a significant place is given to subclinical inflammation and disturbances in the processes of angio-arteriogenesis. Purpose To study blood levels of one of the powerful proangiogenic and proinflammatory factors vascular endothelial growth factor (VEGF) and a marker of inflammation highly sensitive C-reactive protein(hsCRP) in patients with H and AO and their relationship with asymptomatic HMOD. Methods. The study involved 64 patients with grade 2 H and grade I-II AO (38 men and 26 women aged 35 to 60 years) and 23 practically healthy individuals in the control group (14 men and 9 women aged 18 to 50 years).The survey included standard clinical, anthropometrical, biochemical and instrumental methods. The blood levels of VEGF and hsCRP were determined by the enzyme immunoassay. Diagnostics of H, risk factors and HMOD was performed in accordance with the recommendations of the ESC/ESH (2018). Results. There was a significant increase in the blood levels of VEGF (162,31 [102,67; 226,41] pg / ml) and hsCRP (3,11[1,17;5,82] mg/L) in patients with H and AO in general by group in comparison with practically healthy individuals (89,07 [61,43; 135,57] pg/ml (р=0,004) and 1,07 [0,46;2,99] mg/L (р=0,016), respectively). At the same time, the blood levels of VEGF (238,53 [138,31; 294,84] pg/ml) and hsCRP (3,94 [1,89;5,82] mg/L) were significantly higher in patients with LVH than in patients without LVH (149,96 [75,18; 174,96] pg/ml (р=0,035) and 2,30 [0,65; 5,31] mg/L (р=0,042), respectively). The following direct correlations were found: between the blood levels of VEGF and hsCRP (р =0,0018), between the blood levels of EGF, hsCRP and LV mass index (р =0,016, р =0,021, respectively), between the blood levels of VEGF and systolic blood pressure (р =0,035), as well as left atrial volume index (р =0,037). Conclusion. In patients with H in combination with AO, there are manifestations of the activation of the production of proangiogenic and proinflammatory factors -VEGF and hsCRP, which can play an important role in the development of both LVH and in the progression of H in general.

Residual alterations of cardiac and endothelial function in patients who recovered from Takotsubo cardiomyopathy.

IntroductionTakotsubo cardiomyopathy (TCM) is characterized by transient left ventricle dysfunction.HypothesisA residual cardiac and endothelial dysfunction is present in patients who recovered from TCM.MethodsIn this single‐center prospective study, patients with prior TCM were included and followed for 6.4 ± 1.6 years. All underwent comprehensive cardiac function assessment, including tissue Doppler imaging (TDI) and 2‐dimensional strain (2DS) echocardiography at their first visit. The number of circulating endothelial progenitor cells and levels of proangiogenic vascular endothelial growth factor (VEGF) and its receptor (VEGF‐R) were measured. All measurements were compared with healthy controls.ResultsForty‐two women (age 58. ±8.6 years, LVEF 58.1 ± 6.1%) comprised the TCM group. Patients post‐TCM had significantly lower early velocities E′ (6 (5.0–8.0) vs. 9 (7.0–11.0) cm/s, p = .001) by TDI and higher E/E′ ratio (p = .002), lower LV global average longitudinal strain (LGS) (−18.9 ± 3.5% vs. −21.7 ± 2.3%, p = .002) and RV LGS (−20.1 ± 3.9% vs. −23.4 ± 2.8%, p = .003) were evident. There was a trend toward a higher VEGF‐R (p = .09) along with decreased VEGF/VEGF‐R ratio representing inadequate VEGF production. In‐hospital mortality was not reported and only two non‐cardiac deaths occurred at long‐term follow‐up.ConclusionsAltered TDI and 2DS indices suggest residual biventricular myocardial injury in post‐TCM patients with the apparent LV function recovery. Inappropriate production of VEGF and VEGF‐R were observed, suggesting a possible underlying endothelial dysfunction in these patients.

Effect of NIR Laser Therapy by MLS-MiS Source on Fibroblast Activation by Inflammatory Cytokines in Relation to Wound Healing.

The fine control of inflammation following injury avoids fibrotic scars or impaired wounds. Due to side effects by anti-inflammatory drugs, the research is continuously active to define alternative therapies. Among them, physical countermeasures such as photobiomodulation therapy (PBMT) are considered effective and safe. To study the cellular and molecular events associated with the anti-inflammatory activity of PBMT by a dual-wavelength NIR laser source, human dermal fibroblasts were exposed to a mix of inflammatory cytokines (IL-1β and TNF-α) followed by laser treatment once a day for three days. Inducible inflammatory key enzymatic pathways, as iNOS and COX-2/mPGES-1/PGE2, were upregulated by the cytokine mix while PBMT reverted their levels and activities. The same behavior was observed with the proangiogenic factor vascular endothelial growth factor (VEGF), involved in neovascularization of granulation tissue. From a molecular point of view, PBMT retained NF-kB cytoplasmatic localization. According to a change in cell morphology, differences in expression and distribution of fundamental cytoskeletal proteins were observed following treatments. Tubulin, F-actin, and α-SMA changed their organization upon cytokine stimulation, while PBMT reestablished the basal localization. Cytoskeletal rearrangements occurring after inflammatory stimuli were correlated with reorganization of membrane α5β1 and fibronectin network as well as with their upregulation, while PBMT induced significant downregulation. Similar changes were observed for collagen I and the gelatinolytic enzyme MMP-1. In conclusion, the present study demonstrates that the proposed NIR laser therapy is effective in controlling fibroblast activation induced by IL-1β and TNF-α, likely responsible for a deleterious effect of persistent inflammation.

Serum Levels of Vascular Endothelial Growth Factor and Its Receptor in Newly Diagnosed Paediatric Acute Lymphoblastic Leukemia.

Autocrine and paracrine loop involving vascular endothelial growth factor (VEGF) and its receptor have been described in haematological malignancies. However, scarce literature is present on angiogenesis in paediatric acute lymphoblastic leukemia (ALL) with studies showing controversial results. The aim was to study serum levels of VEGF and its receptors in paediatric ALL at the time of diagnosis and at the end of induction phase and to compare these levels with clinico-haematological parameters in these patients. Serum VEGF, VEGFR-1 and VEGFR-2 levels were measured by enzyme-linked immunoabsorbant assay at diagnosis (day 0) and at the end of induction phase (day 35) in 30 newly diagnosed paediatric ALL patients and in 10 healthy controls. Median s-VEGF was significantly lower at day 0 as compared to day 35 (196.15 vs. 606.75pg/ml: p < 0.001). s-VEGFR-1 levels were detectable only in 7 patients at day 0 and were below detection level at day 35 in all patients. Median s-VEGFR-2 at day 0 was significantly lower as compared to day 35 (17,577.5 vs. 20,507.5pg/ml; p = 0.005). Median VEGF-R1 showed an inverse relationship with VEGF-R2 but was statistically insignificant. All patients were in remission at the end of induction. Thus, leukemic infiltration of bone marrow affects angiogenesis and reduces pro-angiogenic markers VEGF and VEGFR-2 in serum possibly due to increased local consumption by blasts. A successful induction leads to clearing of blasts causing restoration of normal hematopoiesis with normalization of VEGF and VEGFR-2 levels.