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Sample records for ca9 erythropoietin vegf

  1. Erythropoietin protects the in vitro blood-brain barrier against VEGF-induced permeability.

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    Martínez-Estrada, Ofelia María; Rodríguez-Millán, Elisabeth; González-De Vicente, Esther; Reina, Manuel; Vilaró, Senén; Fabre, Myriam

    2003-11-01

    The blood-brain barrier (BBB) ensures the homeostasis of the brain microenvironment, mostly through complex tight junctions between brain endothelial cells that prevent the passage of hydrophilic molecules from blood to brain and vice versa. A recent study has shown in vivo that systemic administration of erythropoietin (Epo) protects against brain injury. Using an in vitro model of the bovine BBB, we observed that the expression of the Epo receptor is modulated by its ligand and hypoxic stimuli such as vascular endothelial growth factor (VEGF) treatment. In addition, Epo protects against the VEGF-induced permeability of the BBB, decreases the levels of endothelial nitric oxide synthase and restores junction proteins. The kinetic transport experiments revealed the capacity of Epo to cross the in vitro BBB in a saturable and specific way. Our results suggest a new mechanism for Epo-induced neuroprotection, in which circulating Epo controls and maintains the BBB through an Epo receptor signalling pathway and the re-establishment of cell junctions.

  2. Erythropoietin

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    Miskowiak, Kamilla W; Vinberg, Maj; Harmer, Catherine J

    2012-01-01

    Current pharmacological treatments for depression have a significant treatment-onset-response delay, an insufficient efficacy for many patients and fail to reverse cognitive dysfunction. Erythropoietin (EPO) has neuroprotective and neurotrophic actions and improves cognitive function in animal...... models of acute and chronic neurodegenerative conditions and in patients with cognitive decline....

  3. ERYTHROPOIETIN AS DOPING AGENT

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    Nina Đukanović

    2012-09-01

    Full Text Available Doping is the use of prohibited substances and/or methods that improve the abilities of athletes. Erythropoietin (EPO, the kidney hormone, belongs to a group of substances that are classified as blood doping, and it can be found on the list of banned substances from 1990. year. Its application leads to an increase in the number of red blood cells, which enables better supply of oxygen, and thus improve the aerobic performance of athletes. Because of that, EPO is very popular in sports where the endurance is predominantly required like a marathon, cycling, triathlon, nordic skiing. Erythropoietin can cause some adverse events, primarily to increase blood viscosity, which is associated with a higher risk of various thromboembolic complications. In detection of EPO use two groups of tests are available, through a urine sample (direct method and blood sample (indirect method.

  4. [Erythropoietin administration in diabetic patients].

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    Zukowska-Szczechowska, Ewa; Tomaszewski, Maciej; Sedkowska, Agnieszka; Grzeszczak, Władysław

    2003-01-01

    This paper presents the role of erythropoietin application in diabetic patients with accompanying renal failure. The main cause of anemia in diabetics are: nephropathy, structural lesions of erythrocyte membrane and blood loss connected with diagnostic and therapeutic actions. There are publications which demonstrate that in patients with diabetes type 1 or 2 with accompanying nephropathy, anemia appears more frequently than in the group of patients with chronic renal failure caused by other factors. It is supposed, that the impaired erythropoietin synthesis in diabetics can be caused by autonomic neuropathy. Erythropoietin administration in case of diabetic nephropathy has a beneficial influence on fat metabolism, immune response and reduction of insuline resistance. Erythropoietin because of reduction of vascular endothelial growth factor synthesis blocks the development of diabetic retinopathy and macroangiopathy. Erythropoietin reduces the risk of the left-ventricular hypertrophy caused by anemia. Very important is that the erythropoietin resistance is lower in diabetics. Scientists who are adverse to erythropoietin administration in patients with diabetic nephropathy maintain, that it can lead to vascular complications and the deterioration of glycemia control.

  5. Erythropoietin use and abuse

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    M Joseph John

    2012-01-01

    Full Text Available Recombinant human erythropoietin (rhEPO is arguably the most successful therapeutic application of recombinant DNA technology till date. It was isolated in 1977 and the gene decoded in 1985. Since then, it has found varied applications, especially in stimulating erythropoiesis in anemia due to chronic conditions like renal failure, myelodysplasia, infections like HIV, in prematurity, and in reducing peri-operative blood transfusions. The discovery of erythropoietin receptor (EPO-R and its presence in non-erythroid cells has led to several areas of research. Various types of rhEPO are commercially available today with different dosage schedules and modes of delivery. Their efficacy in stimulating erythropoiesis is dose dependent and differs according to the patient′s disease and nutritional status. EPO should be used carefully according to guidelines as unsolicited use can result in serious adverse effects. Because of its capacity to improve oxygenation, it has been abused by athletes participating in endurance sports and detecting this has proved to be a challenge.

  6. Impacts of CA9 gene polymorphisms on urothelial cell carcinoma susceptibility and clinicopathologic characteristics in Taiwan.

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    Shian-Shiang Wang

    Full Text Available Carbonic anhydrase 9 (CA9 is reportedly overexpressed in several types of carcinomas and is generally considered a marker of malignancy. The current study explored the effect of CA9 gene polymorphisms on the susceptibility of developing urothelial cell carcinoma (UCC and the clinicopathological status.A total of 442 participants, including 221 healthy people and 221 patients with UCC, were recruited for this study. Four single-nucleotide polymorphisms (SNPs of the CA9 gene were assessed by a real-time PCR with the TaqMan assay. After adjusting for other co-variants, the individuals carrying at least one A allele at CA9 rs1048638 had a 2.303-fold risk of developing UCC than did wild-type (CC carriers. Furthermore, UCC patients who carried at least one A allele at rs1048638 had a higher invasive stage risk (p< 0.05 than did patients carrying the wild-type allele. Moreover, among the UCC patients with smoker, people with at least one A allele of CA9 polymorphisms (rs1048638 had a 4.75-fold (95% CI = 1.204-18.746 increased risk of invasive cancer.The rs1048638 polymorphic genotypes of CA9 might contribute to the prediction of susceptibility to and pathological development of UCC. This is the first study to provide insight into risk factors associated with CA9 variants in carcinogenesis of UCC in Taiwan.

  7. Erythropoietin during hypoglycaemia in type 1 diabetes

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    Kristensen, Peter Lommer; Høi-Hansen, Thomas; Olsen, Niels Vidiendal

    2009-01-01

    AIMS: Preservation of cognitive function during hypoglycaemic episodes is crucial for patients with insulin-treated diabetes to avoid severe hypoglycaemic events. Erythropoietin has neuroprotective potential. However, the role of erythropoietin during hypoglycaemia is unclear. The aim of the stud....... CONCLUSIONS: Hypoglycaemia triggers a rise in plasma erythropoietin in patients with type 1 diabetes. The response is influenced by basal RAS activity. Erythropoietin may carry a neuroprotective potential during hypoglycaemia....... was to explore plasma erythropoietin response to hypoglycaemia and the relationship to basal renin-angiotensin system (RAS) activity and cognitive function. METHODS: We performed a single-blinded, controlled, cross-over study with induced hypoglycaemia or maintained glycaemic level. Nine patients with type 1......AIMS: Preservation of cognitive function during hypoglycaemic episodes is crucial for patients with insulin-treated diabetes to avoid severe hypoglycaemic events. Erythropoietin has neuroprotective potential. However, the role of erythropoietin during hypoglycaemia is unclear. The aim of the study...

  8. Behavior of vascular endothelial growth factor and erythropoietin throughout the menstrual cycle in healthy women.

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    Caccamo, Chiara; Nostro, Lorena; Giorgianni, Giovanna; Mondello, Stefania; Crascì, Eleonora; Frisina, Nicola; Buemi, Michele

    2007-11-01

    To evaluate any correlations between erythropoietin (EPO) and vascular endothelial growth factor (VEGF) levels in the serum and the menstrual fluid of healthy women during the different phases of the menstrual cycle. Blood samples from 25 healthy female volunteers were obtained for serum VEGF and EPO detection on the 1st, 7th, 14th, 21st and 25th days of the menstrual cycle. Menstrual fluid samples for VEGF and EPO detection were obtained on the 1st and 4th days of menstruation. Circulating VEGF levels were found to increase in a stage-dependent cyclic manner. The mean VEGF concentration in menstrual blood on the 1st day of the cycle was significantly higher than the mean plasma value and was reduced to a significant extent on the 4th day of the cycle. We found no significant changes in serum EPO levels. Mean EPO concentration detected in menstrual blood was comparable to those in serum blood either on the 1st or 4th day of the menstrual cycle. During menstruation, a local production of VEGF occurs independent of systemic production, thus sustaining angiogenic activity in autonomous, independent ways. Our findings demonstrate the presence of an "open compartment" that reflects the systemic pattern of EPO at the uterine level that allows us to speculate on different effects beyond the angiogenic action of EPO.

  9. The relationship of serum erythropoietin level with coronary collateral grade.

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    Sahinarslan, Asife; Yalcin, Ridvan; Kocaman, Sinan Altan; Ercin, Ugur; Tanalp, Ali Cevat; Topal, Salih; Bukan, Neslihan; Boyaci, Bulent; Cengel, Atiye

    2011-01-01

    Erythropoietin has been shown to induce neovascularization and protect against ischemic vascular injury. We investigated whether a higher serum erythropoietin (EPO) level is related to better coronary collateral vessel grade. Ninety-nine patients with stable angina pectoris who have at least 1 coronary stenosis of equal to or greater than 70% at coronary angiography were prospectively enrolled. Serum EPO and vascular endothelial growth factor (VEGF) levels were studied. Coronary collateral degree was graded according to the Rentrop method. Patients with grade 2-3 collateral degree were included in the good collateral group and formed Group I. The patients with grade 0-1 collateral degree were included in the poor collateral group and formed Group II. The serum EPO level was significantly higher in the good collateral group (17.3 ± 9.3 mU/mL vs 11.7 ± 5.0 mU/mL; P < 0.001). There was also a positive correlation between serum EPO level and Rentrop score (r = 0.39; P < 0.001). In multivariate analysis, serum EPO level (odds ratio [OR] 1.336; 95% confidence interval [CI], 1.120-1.593; P = 0.001), oxygen saturation (OR 0.638; 95% CI, 0.422-0.963; P = 0.033) and presence of chronic total occlusion (CTO) (OR 26.7; 95% CI, 3.874-184.6; P = 0.001) were independently related to well-developed coronary collaterals. Higher serum EPO level is related to better coronary collateral development. Erythropoietin may have a positive effect on the development of collaterals and may provide a new agent for the treatment strategies to enhance coronary collateral vessel development. Copyright © 2011 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  10. Current biology of VEGF-B and VEGF-C.

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    Olofsson, B; Jeltsch, M; Eriksson, U; Alitalo, K

    1999-12-01

    Endothelial growth factors and their receptors may provide important therapeutic tools for the treatment of pathological conditions characterised by defective or aberrant angiogenesis. Vascular endothelial growth factor (VEGF) is pivotal for vasculogenesis and for angiogenesis in normal and pathological conditions. VEGF-B and VEGF-C provide this gene family with additional functions, for example, VEGF-C also regulates lymphangiogenesis.

  11. Effects of erythropoietin on angiogenesis after myocardial infarction in porcine.

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    Kawachi, Keisuke; Iso, Yoshitaka; Sato, Takatoshi; Wakabayashi, Kohei; Kobayashi, Youichi; Takeyama, Youichi; Suzuki, Hiroshi

    2012-01-01

    Erythropoietin (EPO) has recently been shown to confer cardioprotective effects via angiogenesis and antiapoptosis. The administration of EPO after myocardial infarction (MI) reduces infarct size and improves cardiac function in small animals. The purpose of this study is to investigate the protective effects of EPO in porcine MI. Each animal in the EPO group received four injections of recombinant human EPO (rhEPO; 6000 U per injection) at 2-day intervals, starting after coronary occlusion. Animals in the control group received saline. Left ventriculography was performed just after coronary occlusion and at 28 days. Time-course changes in serum levels of vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and fibroblast growth factor (FGF) were measured. The number of vessels was calculated, and the mRNA expressions of VEGF and insulin-like growth factor (IGF) were examined. Left ventricular function was similar between the groups. The numbers of cells positive for anti-α-smooth muscle actin, von Willebrand factor, and c-kit were significantly higher in the EPO group than in the controls (P porcine MI.

  12. Recombinant human erythropoietin in sports: a review

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    Rafael Maia de Almeida Bento

    2003-06-01

    Full Text Available Erythropoietin is an endogenous hormone of glicoproteic nature secreted by the kidneys and is the main regulator of the erythropoiesis. An alteration in its production generates a disturbance in the plasmatic concentration giving rise to several types of pathologies related to the hematopoietic system. The recombinant forms of erythropoietin have indiscriminately been used by athletes, mainly in endurance sports, by increasing the erythrocytes concentration, generating a better delivery of oxygen to the muscle tissue. The administration of recombinant erythropoietin was prohibited by the International Olympic Committee and its use considered as doping. This review has the intention to describe the physical, biological and pharmacokinetic properties of the endogenous erythropoietin, as well as its recombinant form, describing also its use in sports and the process of searching methodologies for its detection in doping control.

  13. Systemic administration of erythropoietin inhibits retinopathy in RCS rats.

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    Weiyong Shen

    Full Text Available OBJECTIVE: Royal College of Surgeons (RCS rats develop vasculopathy as photoreceptors degenerate. The aim of this study was to examine the effect of erythropoietin (EPO on retinopathy in RCS rats. METHODS: Fluorescein angiography was used to monitor retinal vascular changes over time. Changes in retinal glia and vasculature were studied by immunostaining. To study the effects of EPO on retinal pathology, EPO (5000 IU/kg was injected intraperitoneally in 14 week old normal and RCS rats twice a week for 4 weeks. Changes in the retinal vasculature, glia and microglia, photoreceptor apoptosis, differential expression of p75 neurotrophin receptor (p75NTR, pro-neurotrophin 3 (pro-NT3, tumour necrosis factor-α (TNFα, pigment epithelium derived factor (PEDF and vascular endothelial growth factor-A (VEGF-A, the production of CD34(+ cells and mobilization of CD34(+/VEGF-R2(+ cells as well as recruitment of CD34(+ cells into the retina were examined after EPO treatment. RESULTS: RCS rats developed progressive capillary dropout and subretinal neovascularization which were accompanied by retinal gliosis. Systemic administration of EPO stabilized the retinal vasculature and inhibited the development of focal vascular lesions. Further studies showed that EPO modulated retinal gliosis, attenuated photoreceptor apoptosis and p75NTR and pro-NT3 upregulation, promoted the infiltration of ramified microglia and stimulated VEGF-A expression but had little effect on TNFα and PEDF expression. EPO stimulated the production of red and white blood cells and CD34(+ cells along with effective mobilization of CD34(+/VEGF-R2(+ cells. Immunofluorescence study demonstrated that EPO enhanced the recruitment of CD34+ cells into the retina. CONCLUSIONS: Our results suggest that EPO has therapeutic potentials in treatment of neuronal and vascular pathology in retinal disease. The protective effects of EPO on photoreceptors and the retinal vasculature may involve multiple

  14. Erythropoietin in Brain Development and Beyond

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    Mawadda Alnaeeli

    2012-01-01

    Full Text Available Erythropoietin is known as the requisite cytokine for red blood cell production. Its receptor, expressed at a high level on erythroid progenitor/precursor cells, is also found on endothelial, neural, and other cell types. Erythropoietin and erythropoietin receptor expression in the developing and adult brain suggest their possible involvement in neurodevelopment and neuroprotection. During ischemic stress, erythropoietin, which is hypoxia inducible, can contribute to brain homeostasis by increasing red blood cell production to increase the blood oxygen carrying capacity, stimulate nitric oxide production to modulate blood flow and contribute to the neurovascular response, or act directly on neural cells to provide neuroprotection as demonstrated in culture and animal models. Clinical studies of erythropoietin treatment in stroke and other diseases provide insight on safety and potential adverse effects and underscore the potential pleiotropic activity of erythropoietin. Herein, we summarize the roles of EPO and its receptor in the developing and adult brain during health and disease, providing first a brief overview of the well-established EPO biology and signaling, its hypoxic regulation, and role in erythropoiesis.

  15. VEGF121b and VEGF165b are weakly angiogenic isoforms of VEGF-A

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    Pio Ruben

    2010-12-01

    Full Text Available Abstract Background Different isoforms of VEGF-A (mainly VEGF121, VEGF165 and VEGF189 have been shown to display particular angiogenic properties in the generation of a functional tumor vasculature. Recently, a novel class of VEGF-A isoforms, designated as VEGFxxxb, generated through alternative splicing, have been described. Previous studies have suggested that these isoforms may inhibit angiogenesis. In the present work we have produced recombinant VEGF121/165b proteins in the yeast Pichia pastoris and constructed vectors to overexpress these isoforms and assess their angiogenic potential. Results Recombinant VEGF121/165b proteins generated either in yeasts or mammalian cells activated VEGFR2 and its downstream effector ERK1/2, although to a lesser extent than VEGF165. Furthermore, treatment of endothelial cells with VEGF121/165b increased cell proliferation compared to untreated cells, although such stimulation was lower than that induced by VEGF165. Moreover, in vivo angiogenesis assays confirmed angiogenesis stimulation by VEGF121/165b isoforms. A549 and PC-3 cells overexpressing VEGF121b or VEGF165b (or carrying the PCDNA3.1 empty vector, as control and xenotransplanted into nude mice showed increased tumor volume and angiogenesis compared to controls. To assess whether the VEGFxxxb isoforms are differentially expressed in tumors compared to healthy tissues, immunohistochemical analysis was conducted on a breast cancer tissue microarray. A significant increase (p xxxb and total VEGF-A protein expression in infiltrating ductal carcinomas compared to normal breasts was observed. A positive significant correlation (r = 0.404, p = 0.033 between VEGFxxxb and total VEGF-A was found. Conclusions Our results demonstrate that VEGF121/165b are not anti-angiogenic, but weakly angiogenic isoforms of VEGF-A. In addition, VEGFxxxb isoforms are up-regulated in breast cancer in comparison with non malignant breast tissues. These results are to be taken

  16. Impacts of CA9 gene polymorphisms and environmental factors on oral-cancer susceptibility and clinicopathologic characteristics in Taiwan.

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    Ming-Hsien Chien

    Full Text Available BACKGROUND: In Taiwan, oral cancer has causally been associated with environmental carcinogens. Carbonic anhydrase 9 (CA9 is reportedly overexpressed in several types of carcinomas and is generally considered a marker of malignancy. The current study explored the combined effect of CA9 gene polymorphisms and exposure to environmental carcinogens on the susceptibility of developing oral squamous cell carcinoma (OSCC and the clinicopathological characteristics of the tumors. METHODOLOGY AND PRINCIPAL FINDINGS: Four single-nucleotide polymorphisms (SNPs of the CA9 gene from 462 patients with oral cancer and 519 non-cancer controls were analyzed by a real-time polymerase chain reaction (PCR. While the studied SNPs (CA9 rs2071676, rs3829078, rs1048638 and +376 Del were not associated with susceptibility to oral cancer, the GAA haplotype of 3 CA9 SNPs (rs2071676, rs3829078, and rs1048638 was related to a higher risk of oral cancer. Moreover, the four CA9 SNPs combined with betel quid chewing and/or tobacco consumption could robustly elevate susceptibility to oral cancer. Finally, patients with oral cancer who had at least one G allele of CA9 rs2071676 were at higher risk for developing lymph-node metastasis (p = 0.022, compared to those patients homozygous for AA. CONCLUSIONS: Our results suggest that the haplotype of rs2071676, rs3829078, and rs1048638 combined has potential predictive significance in oral carcinogenesis. Gene-environment interactions of CA9 polymorphisms, smoking, and betel-quid chewing might alter oral cancer susceptibility and metastasis.

  17. Symmetric signaling by an asymmetric 1 erythropoietin: 2 erythropoietin receptor complex.

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    Zhang, Yingxin L; Radhakrishnan, Mala L; Lu, Xiaohui; Gross, Alec W; Tidor, Bruce; Lodish, Harvey F

    2009-01-30

    Via sites 1 and 2, erythropoietin binds asymmetrically to two identical receptor monomers, although it is unclear how asymmetry affects receptor activation and signaling. Here we report the design and validation of two mutant erythropoietin receptors that probe the role of individual members of the receptor dimer by selectively binding either site 1 or site 2 on erythropoietin. Ba/F3 cells expressing either mutant receptor do not respond to erythropoietin, but cells co-expressing both receptors respond to erythropoietin by proliferation and activation of the JAK2-Stat5 pathway. A truncated receptor with only one cytosolic tyrosine (Y343) is sufficient for signaling in response to erythropoietin, regardless of the monomer on which it is located. Similarly, only one receptor in the dimer needs a juxtamembrane hydrophobic L253 or W258 residue, essential for JAK2 activation. We conclude that despite asymmetry in the ligand-receptor interaction, both sides are competent for signaling, and appear to signal equally.

  18. Role of Erythropoietin in Renal Anemia Therapy

    African Journals Online (AJOL)

    Larramendi CH, Marco FM, Garcia-Abujeta JL, Mateo M, de la Vega A and Sempere JM. Acute allergic reaction to an iron compound in a milk-allergic patient. Pediatr. Allergy Immunol 2006; 17: 230-233. 18. Ksiazek A. Effect of recombinant human erythropoietin (r-. Hu EPO) therapy on blood pressure in dialysis patients.

  19. Heat transport imaging in the spin-ladder compound Ca9La5Cu24O41

    NARCIS (Netherlands)

    Otter, M.; Krasnikov, V. V.; Fishman, D. A.; Pshenichnikov, M. S.; Saint-Martin, R.; Revcolevschi, A.; van Loosdrecht, P. H. M.

    All-optical heat transport imaging on the spin-ladder compound Ca9La5Cu24O41 is presented. A 'time-of-flight' principle is discussed along with its experimental veri. cation which can be used to measure the bulk thermal diffusion constant. The results of the thermal imaging experiments clearly

  20. Polycythemia in transgenic mice expressing the human erythropoietin gene

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    Semenza, G.L.; Traystman, M.D.; Gearhart, J.D.; Antonarakis, S.E. (Johns Hopkins Univ. School of Medicine, Baltimore, MD (USA))

    1989-04-01

    Erythropoietin is a glycoprotein hormone that regulates mammalian erythropoiesis. To study the expression of the human erythropoietin gene, EPO, 4 kilobases of DNA encompassing the gene with 0.4 kilobase of 5{prime} flanking sequence and 0.7 kilobase of 3{prime} flanking sequence was microinjected into fertilized mouse eggs. Transgenic mice were generated that are polycythemic, with increased erythrocytic indices in peripheral blood, increased numbers of erythroid precursors in hematopoietic tissue, and increased serum erythropoietin levels. Transgenic homozygotes show a greater degree of polycythemia than do heterozygotes as well as striking extramedullary erythropoiesis. Human erythropoietin RNA was found not only in fetal liver, adult liver, and kidney but also in all other transgenic tissues analyzed. Anemia induced increased human erythropoietin RNA levels in liver but not kidney. These transgenic mice represent a unique model of polycythemia due to increased erythropoietin levels.

  1. Use of Recombinant Human Erythropoietin in Renal Anemia in Children

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    Habibur Rahman

    2009-11-01

    Full Text Available Erythropoietin is a hormone highly effective as like as natural erythropoietin to maintain target hemoglobin and hematocrit level in renal anemia. Its advantage over blood transfusion has been proved by improving the quality of life and decreasing morbidity and mortality in ESRD patients. Effectiveness of r-erythropoietin depends on absences of infection, inflammation and vitamin deficiency and iron status. Iron supplementation is needed before r-erythropoietin administration and sub-cutaneous rout is better in renal anemia because of slow and sustained releases of r-erythropoietin from the site of administration. Target hemoglobin level is 11-12.5 gm/dl and hematocrit is 33% which can be achieved by this hormone therapy. Key words- Recombinant erythropoietin, renal anemia, end stage renal disease.DOI: 10.3329/bsmmuj.v2i1.3713 BSMMU J 2009; 2(1: 50-53  

  2. Anemia and elevated systemic levels of vascular endothelial growth factor (VEGF)

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    Dunst, J.; Becker, A.; Lautenschlaeger, C.; Markau, S.; Becker, H.; Fischer, K.; Haensgen, G. [Martin-Luther Univ. Halle-Wittenberg (Germany)

    2002-08-01

    Background: Tissue hypoxia is a major stimulus for the up-regulation of vascular endothelial growth factor (VEGF). Anemia might theoretically impact on angiogenesis via impairment of tissue oxygenation. We have investigated this hypothesis in patients with solid cancers and benign diseases. Patients and methods: 49 patients with untreated locoregionally confined solid cancers of the head and neck, cervix, rectum and lung and 59 additional patients with non-malignant diseases (36 normemic patients without serious diseases and 23 patients with renal anemia) were enrolled and the impact of anemia on plasma VEGF levels were determined. VEGF was measured with a commercially available sandwich enzyme immunoassay technique. Results: Plasma levels of VEGF were 16.2{+-}12.7 pg/ml in 36 normemic patients without malignant disease, 49,2{+-}34.5 pg/ml in 49 patients with cancers (p<0.001), and 89.9{+-}67.8 pg/ml in 23 patients with renal anemia (p=0.001). VEGF levels in cancer patients were significantly correlated with hemoglobin (hb) levels and platelet counts (each p=0.001), but not with type of tumor, stage, histology or age. Patients with cancers had higher plasma levels of VEGF than patients with non-malignant diseases in case of hb{>=}12 g/dl (33.1{+-}17.5 vs. 16.6{+-}13.0 pg/ml, p<0.001) and in case of hb between 11.0 and 11.9 g/dl (56.1{+-}26.4 vs 18.5{+-}14.5 pg/ml, p=0.038). In case of a hb<11 g/dl, plasma VEGF levels were significantly elevated in patients with and without cancers (67.0{+-}47.5 vs 88.9{+-}68.8 pg/ml, n.s.). In a multivariate model, a significant association between low hb levels and increased plasma levels of VEGF was confirmed. In 16 patients with renal anemia, changes in hb under erythropoietin treatment were inversely correlated with changes in plasma VEGF levels with decreasing VEGF after increase in hb (p=0.01). Conclusions: Anemic patients have elevated levels of VEGF. The data suggest that anemia might impact on the progression of

  3. Recombinant human erythropoietin to target cognitive dysfunction in bipolar disorder

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    Miskowiak, Kamilla Woznica; Ehrenreich, Hannelore; Christensen, Ellen M

    2014-01-01

    in erythropoietin versus saline groups (P = .10). However, erythropoietin enhanced sustained attention (P = .001), recognition of happy faces (P = .03), and speed of complex information processing across learning, attention, and executive function (P = .01). These effects occurred in absence of changes in simple...

  4. Umbilical Cord Serum Erythropoietin Levels and Maternal Smoking in Pregnancy

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    Soner Sazak

    2012-01-01

    Full Text Available Objective. To evaluate the effect of maternal smoking during pregnancy on levels of umbilical cord erythropoietin. Methods. Erythropoietin levels were measured in umbilical cord sera of 60 newborns who were delivered vaginally at term. There were 20 (33% smoking and 40 (67% nonsmoking mothers. Results. Mean cord serum erythropoietin levels were significantly lower in the nonsmokers (nonsmokers, 24 ± 9 IU/L; smokers, 61 ± 46 IU/L; P<.001. There was a significant positive correlation between the number of cigarettes smoked per day and cord serum erythropoietin levels (r, 0.58; P≤.05. Conclusions. Smoking during pregnancy is associated with increased levels of umbilical cord erythropoietin at birth. This may indicate a risk of fetal hypoxia and growth restriction. Education and encouragement of cessation of smoking during pregnancy are important to avoid associated fetal and maternal morbidity and mortality.

  5. Specific imaging of VEGF-A expression with radiolabeled anti-VEGF monoclonal antibody.

    NARCIS (Netherlands)

    Stollman, T.H.; Scheer, M.G.W.; Leenders, W.P.J.; Verrijp, K.C.; Soede, A.C.; Oyen, W.J.G.; Ruers, T.J.M.; Boerman, O.C.

    2008-01-01

    Vascular endothelial growth factor-A (VEGF-A) is one of the most important angiogenic factors. Here, we studied in a nude mouse model whether the expression of VEGF-A in a tumor could be imaged with a radiolabeled anti-VEGF antibody. The humanized anti-VEGF-A antibody A.4.6.1. (bevacizumab), which

  6. An abnormally glycosylated isoform of erythropoietin in hemangioblastoma is associated with polycythemia.

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    Delanghe, Sigurd E; Dierick, Jan; Maenhout, Thomas M; Zabeau, Lennart; Tavernier, Jan; Claes, Kathleen; Bleyen, Joris; Delanghe, Joris R

    2015-01-01

    Hemangioblastomas express erythropoietin and the patients often present with polycythemia. Serum erythropoietin was measured using a commercial immunoassay, a functional erythropoietin assay and iso-electric focusing. Despite the polycythemia, serum erythropoietin remained low, while a functional erythropoietin-assay showed a 4-5 higher activity in serum compared to the immunoassay. Iso-electric focusing of serum erythropoietin indicated overrepresentation of highly sialylated erythropoietin isoforms produced by the tumor. As a result, altered affinity of the monoclonal antibody used in the immunoassay for the hypersialylated isoforms was suggested. Analysis of erythropoietin isoforms may be helpful in distinguishing the ectopic erythropoietin isoforms from normally glycosylated erythropoietin. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Erythropoietin Pathway: A Potential Target for the Treatment of Depression

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    Chongyang Ma

    2016-05-01

    Full Text Available During the past decade, accumulating evidence from both clinical and experimental studies has indicated that erythropoietin may have antidepressant effects. In addition to the kidney and liver, many organs have been identified as secretory tissues for erythropoietin, including the brain. Its receptor is expressed in cerebral and spinal cord neurons, the hypothalamus, hippocampus, neocortex, dorsal root ganglia, nerve axons, and Schwann cells. These findings may highlight new functions for erythropoietin, which was originally considered to play a crucial role in the progress of erythroid differentiation. Erythropoietin and its receptor signaling through JAK2 activate multiple downstream signaling pathways including STAT5, PI3K/Akt, NF-κB, and MAPK. These factors may play an important role in inflammation and neuroprogression in the nervous system. This is particularly true for the hippocampus, which is possibly related to learning, memory, neurocognitive deficits and mood alterations. Thus, the influence of erythropoietin on the downstream pathways known to be involved in the treatment of depression makes the erythropoietin-related pathway an attractive target for the development of new therapeutic approaches. Focusing on erythropoietin may help us understand the pathogenic mechanisms of depression and the molecular basis of its treatment.

  8. Erythropoietin Pathway: A Potential Target for the Treatment of Depression.

    Science.gov (United States)

    Ma, Chongyang; Cheng, Fafeng; Wang, Xueqian; Zhai, Changming; Yue, Wenchao; Lian, Yajun; Wang, Qingguo

    2016-05-06

    During the past decade, accumulating evidence from both clinical and experimental studies has indicated that erythropoietin may have antidepressant effects. In addition to the kidney and liver, many organs have been identified as secretory tissues for erythropoietin, including the brain. Its receptor is expressed in cerebral and spinal cord neurons, the hypothalamus, hippocampus, neocortex, dorsal root ganglia, nerve axons, and Schwann cells. These findings may highlight new functions for erythropoietin, which was originally considered to play a crucial role in the progress of erythroid differentiation. Erythropoietin and its receptor signaling through JAK2 activate multiple downstream signaling pathways including STAT5, PI3K/Akt, NF-κB, and MAPK. These factors may play an important role in inflammation and neuroprogression in the nervous system. This is particularly true for the hippocampus, which is possibly related to learning, memory, neurocognitive deficits and mood alterations. Thus, the influence of erythropoietin on the downstream pathways known to be involved in the treatment of depression makes the erythropoietin-related pathway an attractive target for the development of new therapeutic approaches. Focusing on erythropoietin may help us understand the pathogenic mechanisms of depression and the molecular basis of its treatment.

  9. Statistical analysis plan for the Erythropoietin in Traumatic Brain Injury trial: a randomised controlled trial of erythropoietin versus placebo in moderate and severe traumatic brain injury.

    LENUS (Irish Health Repository)

    Presneill, Jeffrey

    2014-01-01

    The Erythropoietin in Traumatic Brain Injury (EPO-TBI) trial aims to determine whether the administration of erythropoietin to patients with moderate or severe traumatic brain injury improves patient-centred outcomes.

  10. Erythropoietine : enkele aspecten van de humorale regulatie van de erythropoiese

    NARCIS (Netherlands)

    G. Wagemaker (Gerard)

    1976-01-01

    textabstractDe regulatie van de erythropoiese verloopt in belangrijke mate via een humorale regulator. Deze wordt erythropoietine genoemd, en heeft een specifieke stimulerende werking op de erythropoiese, waarschiinliik in hoofdzaak door de inductie van erythroide differentiatie in een

  11. Effects of Recombinant Erythropoietin on Breast Cancer-Initiating Cells

    Directory of Open Access Journals (Sweden)

    Tiffany M. Phillips

    2007-12-01

    Full Text Available BACKGROUND: Cancer anemia causes fatigue and correlates with poor treatment outcome. Erythropoietin has been introduced in an attempt to correct these defects. However, five recent clinical trials reported a negative impact of erythropoietin on survival and/or tumor control, indicating that experimental evaluation of a possible direct effect of erythropoietin on cancer cells is required. Cancer recurrence is thought to rely on the proliferation of cancer initiating cells (CICs. In breast cancer, CICs can be identified by phenotypic markers and their fate is controlled by the Notch pathway. METHODS: In this study, we investigated the effect of erythropoietin on CICs in breast cancer cell lines. Levels of erythropoietin receptor (EpoR, CD24, CD44, Jagged-1 expression, activation of Notch-1 were assessed by flow cytometry. Self-renewing capacity of CICs was investigated in sphere formation assays. RESULTS: EpoR expression was found on the surface of CICs. Recombinant human Epo (rhEpo increased the numbers of CICs and self-renewing capacity in a Notch-dependent fashion by induction of Jagged-1. Inhibitors of the Notch pathway and P13-kinase blocked both effects. CONCLUSIONS: Erythropoietin functionally affects CICs directly. Our observation may explain the negative impact of recombinant Epo on local control and survival of cancer patients with EpoR-positive tumors.

  12. Basic conditions for radioimmunoassay of erythropoietin, and plasma levels of erythropoietin in normal subjects and anemic patients

    Energy Technology Data Exchange (ETDEWEB)

    Mizoguchi, Hideaki; Ohta, Kazuo; Suzuki, Toshiaki; Murakami, Akihiko; Ueda, Masatsugu; Sasaki, Ryuzou; Chiba, Hideo

    1987-02-01

    We have developed a specific and sensitive radioimmunoassay for erythropoietin. The sensitivity of our assay is 0.5 mU or 5 mU/ml and is sufficient to detect normal plasma erythropoietin levels. The mean plasma erythropoietin titer of normal Japanese with our radioimmunoassay was found to be 21.9 +- 12.0 mU/ml (n = 199). The validity of the method was further confirmed by the observations that the plasma erythropoietin titers were inversely related to hemoglobin levels in patients with nonuremic anemias, lower in uremic patients than in patients with nonuremic anemias with similar hemoglobin levels, markedly elevated in patients with aplastic anemia and pure red cell aplasia, and in a low normal range in patients with polycythemia vera.

  13. Cell type-specific dependency on the PI3K/Akt signaling pathway for the endogenous Epo and VEGF induction by baicalein in neurons versus astrocytes.

    Directory of Open Access Journals (Sweden)

    Yu-Yo Sun

    Full Text Available The neuroprotective effect of baicalein is generally attributed to inhibition of 12/15-lipoxygenase (12/15-LOX and suppression of oxidative stress, but recent studies showed that baicalein also activates hypoxia-inducible factor-α (HIF1α through inhibition of prolyl hydrolase 2 (PHD2 and activation of the phosphatidylinositide-3 kinase (PI3K/Akt signaling pathway. Yet, the significance and regulation of prosurvival cytokines erythropoietin (Epo and vascular endothelial growth factor (VEGF, two transcriptional targets of HIF1α, in baicalein-mediated neuroprotection in neurons and astrocytes remains unknown. Here we investigated the causal relationship between the PI3K/Akt signaling pathway and Epo/VEGF expression in baicalein-mediated neuroprotection in primary rat cortical neurons and astrocytes. Our results show that baicalein induced Epo and VEGF expression in a HIF1α- and PI3K/Akt-dependent manner in neurons. Baicalein also protected neurons against excitotoxicity in a PI3K- and Epo/VEGF-dependent manner without affecting neuronal excitability. In contrast, at least a 10-fold higher concentration of baicalein was needed to induce Epo/VEGF production and PI3K/Akt activity in astrocytes for protection of neurons. Moreover, only baicalein-induced astrocytic VEGF, but not Epo expression requires HIF1α, while PI3K/Akt signaling had little role in baicalein-induced astrocytic Epo/VEGF expression. These results suggest distinct mechanisms of baicalein-mediated Epo/VEGF production in neurons and astrocytes for neuroprotection, and provide new insights into the mechanisms and potential of baicalein in treating brain injury in vivo.

  14. VEGF(121)b, a new member of the VEGF(xxx)b family of VEGF-A splice isoforms, inhibits neovascularisation and tumour growth in vivo.

    Science.gov (United States)

    Rennel, E S; Varey, A H R; Churchill, A J; Wheatley, E R; Stewart, L; Mather, S; Bates, D O; Harper, S J

    2009-10-06

    The key mediator of new vessel formation in cancer and other diseases is VEGF-A. VEGF-A exists as alternatively spliced isoforms - the pro-angiogenic VEGF(xxx) family generated by exon 8 proximal splicing, and a sister family, termed VEGF(xxx)b, exemplified by VEGF(165)b, generated by distal splicing of exon 8. However, it is unknown whether this anti-angiogenic property of VEGF(165)b is a general property of the VEGF(xxx)b family of isoforms. The mRNA and protein expression of VEGF(121)b was studied in human tissue. The effect of VEGF(121)b was analysed by saturation binding to VEGF receptors, endothelial migration, apoptosis, xenograft tumour growth, pre-retinal neovascularisation and imaging of biodistribution in tumour-bearing mice with radioactive VEGF(121)b. The existence of VEGF(121)b was confirmed in normal human tissues. VEGF(121)b binds both VEGF receptors with similar affinity as other VEGF isoforms, but inhibits endothelial cell migration and is cytoprotective to endothelial cells through VEGFR-2 activation. Administration of VEGF(121)b normalised retinal vasculature by reducing both angiogenesis and ischaemia. VEGF(121)b reduced the growth of xenografted human colon tumours in association with reduced microvascular density, and an intravenous bolus of VEGF(121)b is taken up into colon tumour xenografts. Here we identify a second member of the family, VEGF(121)b, with similar properties to those of VEGF(165)b, and underline the importance of the six amino acids of exon 8b in the anti-angiogenic activity of the VEGF(xxx)b isoforms.

  15. Recombinant erythropoietin in humans has a prolonged effect on circulating erythropoietin isoform distribution

    DEFF Research Database (Denmark)

    Aachmann-Andersen, Niels Jacob; Just Christensen, Søren; Lisbjerg, Kristian

    2014-01-01

    The membrane-assisted isoform immunoassay (MAIIA) quantitates erythropoietin (EPO) isoforms as percentages of migrated isoforms (PMI). We evaluated the effect of recombinant human EPO (rhEPO) on the distribution of EPO isoforms in plasma in a randomized, placebo-controlled, double-blinded, cross...... beta: 73.1 (17.8)% (p=0.039)). In conclusion, Epoetin beta leaves a footprint in the plasma-EPO isoform pattern. MAIIA can detect changes in EPO isoform distribution up til at least three weeks after administration of Epoetin beta even though the total EPO concentration has returned to normal....

  16. Using Anti-VEGF in Diabetic Retinopathy

    OpenAIRE

    Marashi, Ameen

    2016-01-01

    Vascular endothelium growth factor is the main pathological factor in diabetic retinopathy and diabetic macular edema (DME), Anti-VEGF agents are safe and effective in DME treatment, there are multiple Anti-VEGF agents, choosing between them is essential to individualize treatment for each patient to achieve the optimum results.

  17. Erythropoietin blockade inhibits the induction of tumor angiogenesis and progression.

    Directory of Open Access Journals (Sweden)

    Matthew E Hardee

    Full Text Available BACKGROUND: The induction of tumor angiogenesis, a pathologic process critical for tumor progression, is mediated by multiple regulatory factors released by tumor and host cells. We investigated the role of the hematopoietic cytokine erythropoietin as an angiogenic factor that modulates tumor progression. METHODOLOGY/PRINCIPAL FINDINGS: Fluorescently-labeled rodent mammary carcinoma cells were injected into dorsal skin-fold window chambers in mice, an angiogenesis model that allows direct, non-invasive, serial visualization and real-time assessment of tumor cells and neovascularization simultaneously using intravital microscopy and computerized image analysis during the initial stages of tumorigenesis. Erythropoietin or its antagonist proteins were co-injected with tumor cells into window chambers. In vivo growth of cells engineered to stably express a constitutively active erythropoietin receptor EPOR-R129C or the erythropoietin antagonist R103A-EPO were analyzed in window chambers and in the mammary fat pads of athymic nude mice. Co-injection of erythropoietin with tumor cells or expression of EPOR-R129C in tumor cells significantly stimulated tumor neovascularization and growth in window chambers. Co-injection of erythropoietin antagonist proteins (soluble EPOR or anti-EPO antibody with tumor cells or stable expression of antagonist R103A-EPO protein secreted from tumor cells inhibited angiogenesis and impaired tumor growth. In orthotopic tumor xenograft studies, EPOR-R129C expression significantly promoted tumor growth associated with increased expression of Ki67 proliferation antigen, enhanced microvessel density, decreased tumor hypoxia, and increased phosphorylation of extracellular-regulated kinases ERK1/2. R103A-EPO antagonist expression in mammary carcinoma cells was associated with near-complete disruption of primary tumor formation in the mammary fat pad. CONCLUSIONS/SIGNIFICANCE: These data indicate that erythropoietin is an

  18. Erythropoietin in Treatment of Methanol Optic Neuropathy.

    Science.gov (United States)

    Pakdel, Farzad; Sanjari, Mostafa S; Naderi, Asieh; Pirmarzdashti, Niloofar; Haghighi, Anousheh; Kashkouli, Mohsen B

    2018-01-03

    Methanol poisoning can cause an optic neuropathy that is usually severe and irreversible and often occurs after ingestion of illicit or homemade alcoholic beverages. In this study, we evaluated the potential neuroprotective effect of erythropoietin (EPO) on visual acuity (VA) in patients with methanol optic neuropathy. In a prospective, noncomparative interventional case series, consecutive patients with methanol optic neuropathy after alcoholic beverage ingestion were included. All patients initially received systemic therapy including metabolic stabilization and detoxification. Treatment with intravenous recombinant human EPO consisted of 20,000 units/day for 3 successive days. Depending on clinical response, some patients received a second course of EPO. VA, funduscopy, and spectral domain optical coherence tomography were assessed during the study. Main outcome measure was VA. Thirty-two eyes of 16 patients with methanol optic neuropathy were included. Mean age was 34.2 years (±13.3 years). The mean time interval between methanol ingestion and treatment with intravenous EPO was 9.1 days (±5.56 days). Mean follow-up after treatment was 7.5 months (±5.88 months). Median VA in the better eye of each patient before treatment was light perception (range: 3.90-0.60 logMAR). Median last acuity after treatment in the best eye was 1.00 logMAR (range: 3.90-0.00 logMAR). VA significantly increased in the last follow-up examination (P neuropathy and may represent a promising treatment for this disorder.

  19. Blood doping : infusions, erythropoietin and artificial blood.

    Science.gov (United States)

    Eichner, E Randy

    2007-01-01

    As science marches on, athletes and coaches march close behind. Researchers have long been interested in how red cell mass and blood volume affect exercise capacity. Interest in blood doping soared after the 1968 Mexico City Olympics. Studies in the 1970s and 1980s suggested that transfusing red cells could speed endurance performance. Diverse athletes of the time were accused of blood doping. In the late 1980s, recombinant human erythropoietin (EPO) began to supplant transfusion for doping. EPO use is a suspect in nearly 20 deaths in 4 years in European cyclists. In the 1998 Tour de France, a team was ejected for using EPO and six other teams quit the race. The beat goes on; in recent years, diverse endurance and sprint athletes have been caught or accused of using EPO. Tests to detect EPO are improving but are not yet foolproof. As EPO tests improve, blood transfusion is back in vogue and some athletes may have infused artificial blood. Tests for detecting artificial blood also exist, but it seems it will take widespread, year-round, unannounced, out-of-competition testing and stern penalties to deter blood doping.

  20. Cigarette smoke extract (CSE) induces RAGE-mediated inflammation in the Ca9-22 gingival carcinoma epithelial cell line.

    Science.gov (United States)

    Sanders, Nolan T; Dutson, Derek J; Durrant, Justin W; Lewis, Joshua B; Wilcox, Shalene H; Winden, Duane R; Arroyo, Juan A; Bikman, Benjamin T; Reynolds, Paul R

    2017-08-01

    The oral environment is anatomically positioned as a significant gateway for exposure to environmental toxicants. Cigarette smoke exposure compromises oral health by orchestrating inflammation. The receptor for advanced glycation end-products (RAGE) has been implicated in smoke-induced inflammatory effects; however, its role in the oral cavity is unknown. The purpose of this study was to determine RAGE expression by immortalized gingival carcinoma cells and the degree to which RAGE-mediated signaling influences inflammation. Gingival epithelia cells (Ca9-22) were exposed to 10% cigarette smoke extract (CSE) for six hours and screened for RAGE expression and inflammatory mediators. Quantitative PCR and immunoblotting revealed increased RAGE expression following exposure. Furthermore, exposure activated RAGE signaling intermediates including Ras and NF-κB. IL-6 and IL-1β were also elevated in cell culture medium from CSE-exposed cells when compared to controls. A family of anionic, partially lipophilic sulfated polysaccharide derivatives known as semi-synthetic glycosaminoglycan ethers (SAGEs) were used in an effort to block RAGE signaling. Co-treatment of CSE and SAGEs ameliorated inflammatory responses. These results provide a new perspective on a mechanism of cigarette smoke induced oral inflammation. Further work may show RAGE signaling as a potential target in the treatment of diseases of the oral cavity exacerbated by tobacco smoke exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Antiproliferation and Induction of Apoptosis in Ca9-22 Oral Cancer Cells by Ethanolic Extract of Gracilaria tenuistipitata

    Directory of Open Access Journals (Sweden)

    Chi-Chen Yeh

    2012-09-01

    Full Text Available The water extract of Gracilaria tenuistipitata have been found to be protective against oxidative stress-induced cellular DNA damage, but the biological function of the ethanolic extracts of G. tenuistipitata (EEGT is still unknown. In this study, the effect of EEGT on oral squamous cell cancer (OSCC Ca9-22 cell line was examined in terms of the cell proliferation and oxidative stress responses. The cell viability of EEGT-treated OSCC cells was significantly reduced in a dose-response manner (p < 0.0001. The annexin V intensity and pan-caspase activity of EEGT-treated OSCC cells were significantly increased in a dose-response manner (p < 0.05 to 0.0001. EEGT significantly increased the reactive oxygen species (ROS level (p < 0.0001 and decreased the glutathione (GSH level (p < 0.01 in a dose-response manner. The mitochondrial membrane potential (MMP of EEGT-treated OSCC cells was significantly decreased in a dose-response manner (p < 0.005. In conclusion, we have demonstrated that EEGT induced the growth inhibition and apoptosis of OSCC cells, which was accompanied by ROS increase, GSH depletion, caspase activation, and mitochondrial depolarization. Therefore, EEGT may have potent antitumor effect against oral cancer cells.

  2. Genetics of VEGF serum variation in human isolated populations of cilento: importance of VEGF polymorphisms.

    Directory of Open Access Journals (Sweden)

    Daniela Ruggiero

    Full Text Available Vascular Endothelial Growth Factor (VEGF is the main player in angiogenesis. Because of its crucial role in this process, the study of the genetic factors controlling VEGF variability may be of particular interest for many angiogenesis-associated diseases. Although some polymorphisms in the VEGF gene have been associated with a susceptibility to several disorders, no genome-wide search on VEGF serum levels has been reported so far. We carried out a genome-wide linkage analysis in three isolated populations and we detected a strong linkage between VEGF serum levels and the 6p21.1 VEGF region in all samples. A new locus on chromosome 3p26.3 significantly linked to VEGF serum levels was also detected in a combined population sample. A sequencing of the gene followed by an association study identified three common single nucleotide polymorphisms (SNPs influencing VEGF serum levels in one population (Campora, two already reported in the literature (rs3025039, rs25648 and one new signal (rs3025020. A fourth SNP (rs41282644 was found to affect VEGF serum levels in another population (Cardile. All the identified SNPs contribute to the related population linkages (35% of the linkage explained in Campora and 15% in Cardile. Interestingly, none of the SNPs influencing VEGF serum levels in one population was found to be associated in the two other populations. These results allow us to exclude the hypothesis that the common variants located in the exons, intron-exon junctions, promoter and regulative regions of the VEGF gene may have a causal effect on the VEGF variation. The data support the alternative hypothesis of a multiple rare variant model, possibly consisting in distinct variants in different populations, influencing VEGF serum levels.

  3. AMPK-KLF2 signaling pathway mediates the proangiogenic effect of erythropoietin in endothelial colony forming cells.

    Science.gov (United States)

    Wang, Dawei; Song, Yimeng; Zhang, Jianshu; Pang, Wei; Wang, Xian; Zhu, Yi; Li, Xiaoxia

    2017-10-04

    Endothelial colony forming cells (ECFCs) were proved to take part in post-natal vasculogenesis and injury repair. The angiogenic properties of ECFCs could be influenced by various cytokines, chemokines, and growth factors. Erythropoietin (EPO) is a promising cytokine participating in angiogenesis. However, the mechanisms for EPO's proangiogenic effect still remain largely elusive. Here, we investigated the role of AMP-activated protein kinase (AMPK)-Krüppel-like factor 2 (KLF2) signaling pathway in the proangiogenic effect of EPO in ECFCs. Human ECFCs were isolated from cord blood and cultured. EPO significantly enhanced the migration and tube formation capacities of ECFCs and markedly increased the expression of endothelial markers and vascular endothelial growth factor (VEGF). Further, EPO caused the phosphorylation of AMPK and endothelial nitric oxide synthase (eNOS), in which process KLF2 was also up-regulated on both mRNA and protein levels. The up-regulation of KLF2 was blocked by inhibiting AMPK with Compound C or Ad-AMPK-DN, a recombinant adenovirus which encoded a dominant negative mutant of AMPK. Furthermore, knockdown of KLF2 showed no effect on AMPK but abolished the EPO-enhanced migration and tube formation capacities of ECFCs. Of note, knockdown of KLF2 also diminished the EPO-induced expression of endothelial markers and VEGF; overexpression of KLF2 promoted the expression of endothelial markers and VEGF and enhanced the migration and tube formation capacities of ECFCs. These data suggest that up-regulation of KLF2 by AMPK plays an essential role in EPO-induced angiogenesis. Copyright © 2017, American Journal of Physiology-Cell Physiology.

  4. VEGF and endothelial guidance in angiogenic sprouting.

    Science.gov (United States)

    Gerhardt, Holger

    2008-10-01

    The cellular actions of VEGF need to be coordinated to guide vascular patterning during sprouting angiogenesis. Individual endothelial tip cells lead and guide the blood vessel sprout, while neighbouring stalk cells proliferate and form the vascular lumen. Recent studies illustrate how endothelial DLL4/NOTCH signalling, stimulated by VEGF, regulates the sprouting response by limiting tip cell formation in the stalk. The spatial distribution of VEGF, in turn, regulates the shape of the ensuing sprout by directing tip cell migration and determining stalk cell proliferation.

  5. Central nervous system frontiers for the use of erythropoietin

    DEFF Research Database (Denmark)

    Olsen, Niels Vidiendal

    2003-01-01

    Recombinant human erythropoietin (r-HuEPO; epoetin alfa) is well established as safe and effective for the treatment of anemia. In addition to the erythropoietic effects of endogenous erythropoietin (EPO), recent evidence suggests that it may elicit a neuroprotective effect in the central nervous...... system (CNS). Preclinical studies have demonstrated the presence of EPO receptors in the brain that are up-regulated under hypoxic or ischemic conditions. Intracerebral and systemic administration of epoetin alfa have been demonstrated to elicit marked neuroprotective effects in multiple preclinical...

  6. Is the use of recombinant human erythropoietin in anaemia of ...

    African Journals Online (AJOL)

    In a double-blind placebo-eontrolled study we showed a 3-fold decrease in blood transfusions (BTFs) given to preterm infants with anaemia of prematurity who received recombinant erythropoietin. However, only 50% of placebo recipients required a BTF. Data from the placebo group indicated that either mean daily weight ...

  7. Erythropoietin protects the retinal pigment epithelial barrier against ...

    African Journals Online (AJOL)

    Erythropoietin (EPO) is not limited to hematopoiesis; it may act as a protective cytokine. In this study, the retinal pigment epithelial (RPE) cell viability, cell monolayer integrity, RPE barrier permeability, distribution of the junction proteins ZO-1, occludin and the levels of superoxide dismutase (SOD) and malondialdehyde ...

  8. Effect of recombinant human erythropoietin expressions of apoptosis ...

    African Journals Online (AJOL)

    Effect of recombinant human erythropoietin expressions of apoptosis genes in rats following traumatic brain injury. Xuesong Yuan1*, Xiaoxing Bian1, Wenfeng Wei1, Yin Tang2 and Qing Bao1. 1Department of Neurosurgery, 2Department of Pathology, The Affiliated Wujin Hospital of Jiangsu University, Changzhou. Jiangsu ...

  9. CORRECTION OF ANAEMIA WITH ERYTHROPOIETIN IN CKD/ESRD PATIENTS

    OpenAIRE

    Madhukar,; Shyamal; Rashmi; Anitha; Bhattacharjee; Anjaiah; Abdul; Kunal,

    2015-01-01

    Chronic kidney disease ( CKD) is characterized by gradual and permanent loss of kidney function. One of the most common complications of CKD is Anaemia . 1,3 Anaemia often appears earlier in course of CKD and worsens with disease progression. 1,2 Erythropoietin is a hormone synthesized in the kidney is deficient in the majority of ...

  10. Treatment of anemia of nephrotic syndrome with recombinant erythropoietin

    NARCIS (Netherlands)

    Gansevoort, RT; Vaziri, ND; deJong, PE

    Nephrotic syndrome has been recently shown to cause erythropoietin (EPO) deficiency in humans and experimental models. However, efficacy and safety of recombinant EPO (rEPO) in the treatment of the associated anemia has not been previously investigated. We report a patient with nephrotic syndrome

  11. Study the relationship of erythropoietin and chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    R.I. El-Korashy

    2012-07-01

    It also appeared that response to erythropoietin in COPD is probably blunted especially with increased severity of the condition. This might be considered as a contributing factor in the development of anemia in COPD which is considered as anemia of chronic disease.

  12. Recombinant erythropoietin found in seized blood bags from sportsmen.

    Science.gov (United States)

    Mallorquí, Joaquim; Segura, Jordi; de Bolòs, Carme; Gutiérrez-Gallego, Ricardo; Pascual, Jose A

    2008-02-01

    During an anti-doping investigation, the Spanish Guardia Civil confiscated blood bags from elite sportsmen. A novel immuno-purification method demonstrated that plasma samples with elevated erythropoietin (EPO) contained recombinant material (rEPO). This shows that rEPO is used before autologous blood transfusions and that rEPO analysis in plasma can be reliably addressed.

  13. The potential protective effects of erythropoietin and estrogen on ...

    African Journals Online (AJOL)

    Background: Renal ischemia–reperfusion (RIR) is an important etiopathological mechanism of acute renal failure (ARF). Erythropoietin (EPO) has been candidate as a nephroprotectant agent. However, its nephroprotective effect when it is accompanied with estrogen has not been studied in female. Methods: Fifty-six female ...

  14. Diurnal variations of serum erythropoietin at sea level and altitude

    DEFF Research Database (Denmark)

    Klausen, T; Poulsen, T D; Fogh-Andersen, N

    1996-01-01

    This study tested the hypothesis that the diurnal variations of serum-erythropoietin concentration (serum-EPO) observed in normoxia also exist in hypoxia. The study also attempted to investigate the regulation of EPO production during sustained hypoxia. Nine subjects were investigated at sea leve...

  15. The synthesis and luminescence properties of a novel red-emitting phosphor: Eu3+-doped Ca9La(PO4)7

    Science.gov (United States)

    Liang, Zehui; Mu, Zhongfei; Wang, Qiang; Zhu, Daoyun; Wu, Fugen

    2017-10-01

    A series of novel red-emitting phosphors Ca9La1- x (PO4)7: xEu3+ were synthesized by high-temperature solid state reactions. The photoluminescence excitation and photoluminescence spectra of these phosphors were investigated in detail. O2--Eu3+ charge transfer band peaking at about 261 nm is dominant in the PLE spectra of Eu3+-doped Ca9La(PO4)7, indicating that the phosphors are suitable for tricolor fluorescent lamps. The phosphors also show a good absorption in near ultraviolet (around 395 nm) and blue (around 465 nm) spectral region, which indicates that it can be pumped with NUV and blue chips for white light-emitting diodes. The transition of 5D0 → 7F2 of Eu3+ in this lattice can emit bright red light. Ca9La(PO4)7 could accommodate a large amount of Eu3+ with an optimal concentration of 60 mol%. The dipole-dipole interaction between Eu3+ is the dominant mechanism for concentration quenching of Eu3+. The calculated color coordinates lie in red region ( x = 0.64, y = 0.36), which is close to Y2O3: 0.05Eu3+ ( x = 0.65, y = 0.34). The integral emission intensity of Ca9La0.4(PO4)7: 0.6Eu3+ is 1.9 times stronger than that of widely used commercial red phosphor Y2O3: 0.05Eu3+. All these results indicate that Eu3+-doped Ca9La(PO4)7 is a promising red-emitting phosphor which can be used in tricolor fluorescent lamps and white light-emitting diodes.

  16. Renal Cell Protection of Erythropoietin beyond Correcting The Anemia in Chronic Kidney Disease Patients.

    Science.gov (United States)

    Nasri, Hamid

    2014-01-01

    Currently many patients with chronic renal failure have profited from the use of erythropoietin to correct anemia (1,2). In chronic kidney disease, anemia is believed to be a surrogate index for tissue hypoxia that continues preexisting renal tissue injury (1-3). Erythropoietin is an essential glycoprotein that accelerates red blood cell maturation from erythroid progenitors and facilitates erythropoiesis. It is a 30.4 kD glycoprotein and class I cytokine containing 165 amino acids (3,4). Approximately 90% of systemic erythropoietin in adults is produced by peritubular interstitial fibroblasts in the renal cortex and outer medulla of the kidney (3-5). A feedback mechanism involving oxygen delivery to the tissues seems to regulate erythropoietin production. Hypoxia-inducible factor regulates transcription of the erythropoietin gene in the kidney, which determines erythropoietin synthesis (3-5). Erythropoietin is an essential glycoprotein that accelerates red blood cell maturation from erythroid progenitors and mediates erythropoiesis in the bone marrow (4-6). Kidney fibrosis is the last common pathway in chronic renal failure irrespective of the initial etiology (5,6). Constant inflammatory cell infiltration and pericyte-myofibroblast transition lead to renal fibrosis and insufficiency which result in decreased production of erythropoietin (4-7). Thus far, therapeutic efforts to treat patients with chronic renal failure by administering erythropoietin have been made only to correct anemia and putative hypoxic tissue damage. The introduction of recombinant human erythropoietin has marked a significant advance in the management of anemia associated with chronic renal failure (6-9). With an increasing number of patients with chronic renal failure receiving erythropoietin treatment, emerging evidence suggests that erythropoietin not only has an erythropoietic function, but also has renoprotective potential. In fact, in recent years, the additional non

  17. Evaluation of functional erythropoietin receptor status in skeletal muscle in vivo

    DEFF Research Database (Denmark)

    Christensen, Britt; Lundby, Carsten; Jessen, Niels

    2012-01-01

    as activation of Epo signalling pathways (STAT5, MAPK, Akt, IKK) were analysed by western blotting. Changes in muscle protein profiles after prolonged erythropoietin treatment were evaluated by 2D gel-electrophoresis and mass spectrometry. The presence of the erythropoietin receptor in skeletal muscle......Background: Erythropoietin receptors have been identified in human skeletal muscle tissue, but downstream signal transduction has not been investigated. We therefore studied in vivo effects of systemic erythropoietin exposure in human skeletal muscle. Methodology/Principal Findings: The protocols...... involved 1) acute effects of a single bolus injection of erythropoietin followed by consecutive muscle biopsies for 1-10 hours, and 2) a separate study with prolonged administration for 16 days with biopsies obtained before and after. The presence of erythropoietin receptors in muscle tissue as well...

  18. Anti-Erythropoietin Antibody Associated Pure Red Cell Aplasia Resolved after Liver Transplantation.

    Science.gov (United States)

    Hung, Annie K; Guy, Jennifer; Behler, Caroline M; Lee, Eugene E

    2015-01-01

    Patients undergoing antiviral therapy for chronic hepatitis C often develop anemia secondary to ribavirin and interferon. Recombinant erythropoietin has been used to improve anemia associated with antiviral therapy and to minimize dose reductions, which are associated with decreased rates of sustained virologic response. A rare potential side effect of recombinant erythropoietin is anti-erythropoietin antibody associated pure red cell aplasia. In chronic kidney disease patients with this entity, there have been good outcomes associated with renal transplant and subsequent immunosuppression. In this case, a chronic liver disease patient developed anti-erythropoietin associated pure red cell aplasia and recovered after liver transplantation and immunosuppression. It is unclear whether it is the transplanted organ, the subsequent immunosuppression, or the combination that contributed to the response. In conclusion, anti-erythropoietin associated pure red cell aplasia is a serious complication of erythropoietin therapy, but this entity should not be considered a contraindication for solid organ transplantation.

  19. Anti-Erythropoietin Antibody Associated Pure Red Cell Aplasia Resolved after Liver Transplantation

    Directory of Open Access Journals (Sweden)

    Annie K. Hung

    2015-01-01

    Full Text Available Patients undergoing antiviral therapy for chronic hepatitis C often develop anemia secondary to ribavirin and interferon. Recombinant erythropoietin has been used to improve anemia associated with antiviral therapy and to minimize dose reductions, which are associated with decreased rates of sustained virologic response. A rare potential side effect of recombinant erythropoietin is anti-erythropoietin antibody associated pure red cell aplasia. In chronic kidney disease patients with this entity, there have been good outcomes associated with renal transplant and subsequent immunosuppression. In this case, a chronic liver disease patient developed anti-erythropoietin associated pure red cell aplasia and recovered after liver transplantation and immunosuppression. It is unclear whether it is the transplanted organ, the subsequent immunosuppression, or the combination that contributed to the response. In conclusion, anti-erythropoietin associated pure red cell aplasia is a serious complication of erythropoietin therapy, but this entity should not be considered a contraindication for solid organ transplantation.

  20. Erythropoietin and carbamylated erythropoietin promote histone deacetylase 5 phosphorylation and nuclear export in rat hippocampal neurons

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Hye-Ryeong [Department of Biomedical Sciences, Graduate School of Biomedical Science and Engineering (Korea, Republic of); Kim, Yong-Seok [Department of Biomedical Sciences, Graduate School of Biomedical Science and Engineering (Korea, Republic of); Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, 17 Haengdang-dong, Sungdong-gu, Seoul 133-791 (Korea, Republic of); Son, Hyeon, E-mail: hyeonson@hanyang.ac.kr [Department of Biomedical Sciences, Graduate School of Biomedical Science and Engineering (Korea, Republic of); Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, 17 Haengdang-dong, Sungdong-gu, Seoul 133-791 (Korea, Republic of)

    2016-01-29

    Erythropoietin (EPO) produces neurotrophic effects in animal model of neurodegeneration. However, clinical use of EPO is limited due to thrombotic risk. Carbamylated EPO (cEPO), devoid of thrombotic risk, has been proposed as a novel neuroprotective and neurotrophic agent although the molecular mechanisms of cEPO remain incomplete. Here, we show a previously unidentified role of histone deacetylase 5 (HDAC5) in the actions of EPO and cEPO. EPO and cEPO regulate the HDAC5 phosphorylation at two critical sites, Ser259 and Ser498 through a protein kinase D (PKD) dependent pathway. In addition, EPO and cEPO rapidly stimulates nuclear export of HDAC5 in rat hippocampal neurons which expressing HDAC5-GFP. Consequently, EPO and cEPO enhanced the myocyte enhancer factor-2 (MEF2) target gene expression. Taken together, our results reveal that EPO and cEPO mediate MEF2 target gene expression via the regulation of HDAC5 phosphorylation at Ser259/498, and suggest that HDAC5 could be a potential mechanism contributing to the therapeutic actions of EPO and cEPO.

  1. VEGF, sVEGFR-1 and Endostatin Serum Levels and VEGF Polymorphisms in Recurrent Aphthous Stomatitis

    Directory of Open Access Journals (Sweden)

    Salim Yuce

    2016-09-01

    Full Text Available Aim: Recurrent aphthous stomatitis (RAS is one of the most frequent diseases of the oral mucosa, characterized by chronic, painful, recurrent, and necrotizing ulcerations. The precise etiology and pathogenesis of RAS have not been clarified. Therefore, we aimed to investigate serum levels of VEGF, sVEGFR-1, and endostatin as well as the frequencies of VEGF 936 C/T and -1154 G/A single nucleotide polymorphisms (SNPs in Turkish patients with recurrent aphthous stomatitis. Material and Method: Forty-two patients with RAS (24 minor RAS and 18 major RAS and 37 healthy subjects were included in the study. Serum levels of VEGF, sVEGFR-1, and endostatin were measured using the ELISA method. VEGF 936 C/T and -1154 G/A SNPs were determined by the PCR-RFLP method. Results: The mean serum level of VEGF was found higher in bearing CC genotype of 936 C/T SNP compared with CT genotype (639.5 ± 309.1 vs 442.1 ± 197.8; p = 0.032. VEGF -1154 GA genotype was found to be more frequent in patients with minor RAS and GG genotype was more frequent in patients with major RAS (p = 0.022. There was a significant difference between minor RAS and major RAS with regard to mean VEGF serum levels (677.1 ± 316.7 vs 492.9 ± 242.7; p = 0.032.Discussion: The T allele of 936 C/T SNP is associated with decreased serum VEGF level, and this decrease may have a contributory role in impaired neovascularization and re-epithelialization in the etiology and pathogenesis of RAS. Further studies are needed to determine the role of VEGF in RAS susceptibility and its clinical manifestations.

  2. Neuroprotective properties of a novel, non-haematopoietic agonist of the erythropoietin receptor

    DEFF Research Database (Denmark)

    Pankratova, Stanislava; Kiryushko, Dar'Ya; Sonn, Katrin

    2010-01-01

    , but with 10(3)-fold lower potency. Knockdown of the erythropoietin receptor or interference with its downstream signalling inhibited the Epotris-induced neuritogenic and pro-survival effect. Similarly to erythropoietin, Epotris penetrated the blood-brain barrier. Moreover, treatment with the peptide...... attenuated seizures, decreased mortality and reduced neurodegeneration in an in vivo model of kainic acid-induced neurotoxicity. In contrast to erythropoietin, Epotris did not stimulate erythropoiesis upon chronic administration. Thus, Epotris is a novel neuroprotective non-haematopoietic erythropoietin...

  3. Erythropoietin and interleukin-2 activate distinct JAK kinase family members.

    OpenAIRE

    Barber, D L; D'Andrea, A D

    1994-01-01

    The erythropoietin (EPO) receptor and the interleukin-2 (IL-2) receptor beta-chain subunit are members of the cytokine receptor superfamily. They have conserved primary amino acid sequences in their cytoplasmic domains and activate phosphorylation of common substrates, suggesting common biochemical signaling mechanisms. We have generated a cell line, CTLL-EPO-R, that contains functional cell surface receptors for both EPO and IL-2. CTLL-EPO-R cells demonstrated similar growth kinetics in EPO ...

  4. Erythropoietin and hypothermia for hypoxic-ischemic encephalopathy.

    Science.gov (United States)

    Rogers, Elizabeth E; Bonifacio, Sonia L; Glass, Hannah C; Juul, Sandra E; Chang, Taeun; Mayock, Dennis E; Durand, David J; Song, Dongli; Barkovich, Anthony J; Ballard, Roberta A; Wu, Yvonne W

    2014-11-01

    Erythropoietin is neuroprotective in animal models of neonatal hypoxic-ischemic encephalopathy. We previously reported a phase I safety and pharmacokinetic study of erythropoietin in neonates. This article presents the neurodevelopmental follow-up of infants who were enrolled in the phase I clinical trial. We enrolled 24 newborns with hypoxic-ischemic encephalopathy in a dose-escalation study. Patients received up to six doses of erythropoietin in addition to hypothermia. All infants underwent neonatal brain magnetic resonance imaging (MRI) reviewed by a single neuroradiologist. Moderate-to-severe neurodevelopmental disability was defined as cerebral palsy with Gross Motor Function Classification System levels III-V or cognitive impairment based on Bayley Scales of Infant Development II mental developmental index or Bayley III cognitive composite score. Outcomes were available for 22 of 24 infants, at mean age 22 months (range, 8-34 months). There were no deaths. Eight (36%) had moderate-to-severe brain injury on neonatal MRI. Moderate-to-severe disability occurred in one child (4.5%), in the setting of moderate-to-severe basal ganglia and/or thalamic injury. Seven infants with moderate-to-severe watershed injury exhibited the following outcomes: normal (three), mild language delay (two), mild hemiplegic cerebral palsy (one), and epilepsy (one). All 11 patients with a normal brain MRI had a normal outcome. This study is the first to describe neurodevelopmental outcomes in infants who received high doses of erythropoietin and hypothermia during the neonatal period. The findings suggest that future studies are warranted to assess the efficacy of this new potential neuroprotective therapy. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Does erythropoietin cause hemoglobin variability--is it 'normal'?

    Directory of Open Access Journals (Sweden)

    Ashwani K Gupta

    Full Text Available Hemoglobin variability (Hb-var in patients with chronic kidney disease has been stipulated to be a result of exogenous treatment with erythropoiesis stimulating agents (ESA and has been related to mortality in dialysis patients. We hypothesized the existence of Hb-var independent of ESA administration and compared it to that in healthy adults using data from the Scripps-Kaiser and NHANES III databases. We studied the Hb-var in 1571 peritoneal dialysis patients which included 116 patients not requiring treatment with erythropoietin. We systematically studied the differences between the groups that needed ESA therapy and those who did not. White race and male sex were significant predictors of need for erythropoietin therapy. We found peritoneal dialysis patients to exhibit significantly increased Hb-var independent of treatment with exogenous erythropoietin (0.99 gm/dL vs. 1.17 gm/dL, p-value60 years peritoneal dialysis patients was similar to that seen in healthy elders, suggesting similarity with anemia of aging. We conclude that exogenous ESA administration does not explain Hb-var entirely but may enhance it. Intrinsic factors affecting erythropoiesis including age may be the major determinants of Hb-var.

  6. Designing a small molecule erythropoietin mimetic.

    Science.gov (United States)

    Guarnieri, Frank

    2015-01-01

    Erythropoietin (EPO) is a protein made by the kidneys in response to low red blood cell count that is secreted into the bloodstream and binds to a receptor on hematopoietic stem cells in the bone marrow inducing them to become new red blood cells. EPO made with recombinant DNA technology was brought to market in the 1980s to treat anemia caused by kidney disease and cancer chemotherapy. Because EPO infusion was able to replace blood transfusions in many cases, it rapidly became a multibillion dollar per year drug and as the first biologic created with recombinant technology it launched the biotech industry. For many years intense research was focused on creating a small molecule orally available EPO mimetic. The Robert Wood Johnson (RWJ) group seemed to definitively establish that only large peptides with a minimum of 60 residues could replace EPO, as anything less was not a full agonist. An intense study of the published work led me to hypothesize that the size of the mimetic is not the real issue, but the symmetry making and breaking of the EPO receptor induced by the ligand is the key to activating the stem cells. This analysis meant that residues in the binding site of the receptor deemed absolutely essential for ligand binding and activation from mutagenesis experiments, were probably not really that important. My fundamental hypotheses were: (a) the symmetric state of the homodimeric receptor is the most stable state and thus must be the off-state, (b) a highly localized binding site exists at a pivot point where the two halves of the receptor meet, (c) small molecules can be created that have high potency for this site that will be competitive with EPO and thus can displace the protein-protein interaction, (d) small symmetric molecules will stabilize the symmetric off-state of the receptor, and (e) a key asymmetry in the small molecule will stabilize a mirror image asymmetry in the receptor resulting in the stabilization of the on-state and proliferation of

  7. Comparing protein VEGF inhibitors: In vitro biological studies

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Lanlan; Liang, Xiao Huan [Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080 (United States); Ferrara, Napoleone, E-mail: nf@gene.com [Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080 (United States)

    2011-05-06

    Highlights: {yields} VEGF is a mediator of angiogenesis. {yields} VEGF inhibitors have clinical applications in cancer and eye disorders. {yields} Five protein VEGF inhibitors were compared for their ability to inhibit. {yields} VEGF-induced activities in cultured endothelial cells. -- Abstract: VEGF inhibitors are widely used as a therapy for tumors and intravascular neovascular disorders, but limited and conflicting data regarding their relative biological potencies are available. The purpose of the study is to compare different protein VEGF inhibitors for their ability to inhibit VEGF-stimulated activities. We tested ranibizumab, the full-length variant of ranibizumab (Mab Y0317), bevacizumab, the VEGF-TrapR1R2 and Flt(1-3)-IgG in bioassays measuring VEGF-stimulated proliferation of bovine retinal microvascular endothelial cells or chemotaxis of human umbilical vein endothelial cells (HUVEC). The inhibitors were also compared for their ability to inhibit MAP kinase activation in HUVECs following VEGF addition. Ranibizumab, VEGF-TrapR1R2 and Flt(1-3)-IgG had very similar potencies in the bioassays tested. Bevacizumab was over 10-fold less potent than these molecules. Mab Y0317 was over 30-fold more potent than bevacizumab. The findings reported in this manuscript describe important intrinsic characteristics of several VEGF inhibitors that may be useful to design and interpret preclinical or clinical studies.

  8. Erythropoietin in the general population: reference ranges and clinical, biochemical and genetic correlates.

    Directory of Open Access Journals (Sweden)

    Niels Grote Beverborg

    Full Text Available Although erythropoietin has been used for decades in the treatment of anemia, data regarding endogenous levels in the general population are scarce. Therefore, we determined erythropoietin reference ranges and its clinical, biochemical and genetic associations in the general population.We used data from 6,777 subjects enrolled in the Prevention of REnal and Vascular ENd-stage Disease (PREVEND study. Fasting venous blood samples were obtained in the morning from all participants from 2001-2003. Serum erythropoietin concentrations were measured using a fully automated chemiluminescent enzyme-labeled immunometric assay. A genome-wide association study was performed to identify genetic determinants.Mean age (± SD was 53 ± 12 years and 50% were female. Median (IQR erythropoietin concentrations were 7.6 (5.8-9.9 IU/L in men and 7.9 (6.0-10.6 IU/L in women. A strong positive correlation was found between erythropoietin and waist circumference, glucose and systolic blood pressure (all P < 0.05. In subjects with normal renal function there was a strong exponential relation between hemoglobin and erythropoietin, whereas in renal impairment (eGFR < 60 mL/min/1.73m² this relation was linear (men or absent (women (P < 0.001 for interaction. Single-nucleotide polymorphisms at the HBS1L-MYB locus were shown to be related to erythropoietin levels (P < 9x10-21, more significantly than other erythrocyte parameters.We provide age-specific reference ranges for endogenous serum erythropoietin. Erythropoietin levels are positively associated with the components of the metabolic syndrome, except cholesterol. We show that even mild renal failure blunts erythropoietin production and propose the HBS1L-MYB locus as a regulator of erythropoietin.

  9. Alginate hydrogels allow for bioactive and sustained release of VEGF-C and VEGF-D for lymphangiogenic therapeutic applications.

    Science.gov (United States)

    Campbell, Kevin T; Hadley, Dustin J; Kukis, David L; Silva, Eduardo A

    2017-01-01

    Lymphatic dysfunction is associated with the progression of many cardiovascular disorders due to their role in maintaining tissue fluid homeostasis. Promoting new lymphatic vessels (lymphangiogenesis) is a promising strategy to reverse these cardiovascular disorders via restoring lymphatic function. Vascular endothelial growth factor (VEGF) members VEGF-C and VEGF-D are both potent candidates for stimulating lymphangiogenesis, though maintaining spatial and temporal control of these factors represents a challenge to developing efficient therapeutic lymphangiogenic applications. Injectable alginate hydrogels have been useful for the controlled delivery of many angiogenic factors, including VEGF-A, to stimulate new blood vasculature. However, the utility of these tunable hydrogels for delivering lymphangiogenic factors has never been closely examined. Thus, the objective of this study was to utilize ionically cross-linked alginate hydrogels to deliver VEGF-C and VEGF-D for potential lymphangiogenic applications. We demonstrated that lymphatic endothelial cells (LECs) are sensitive to temporal presentation of VEGF-C and VEGF-D but with different responses between the factors. The greatest LEC mitogenic and sprouting response was observed for constant concentrations of VEGF-C and a high initial concentration that gradually decreased over time for VEGF-D. Additionally, alginate hydrogels provided sustained release of radiolabeled VEGF-C and VEGF-D. Finally, VEGF-C and VEGF-D released from these hydrogels promoted a similar number of LEC sprouts as exogenously added growth factors and new vasculature in vivo via a chick chorioallantoic membrane (CAM) assay. Overall, these findings demonstrate that alginate hydrogels can provide sustained and bioactive release of VEGF-C and VEGF-D which could have applications for therapeutic lymphangiogenesis.

  10. Recombinant erythropoietin in humans has a prolonged effect on circulating erythropoietin isoform distribution.

    Directory of Open Access Journals (Sweden)

    Niels Jacob Aachmann-Andersen

    Full Text Available The membrane-assisted isoform immunoassay (MAIIA quantitates erythropoietin (EPO isoforms as percentages of migrated isoforms (PMI. We evaluated the effect of recombinant human EPO (rhEPO on the distribution of EPO isoforms in plasma in a randomized, placebo-controlled, double-blinded, cross-over study. 16 healthy subjects received either low-dose Epoetin beta (5000 IU on days 1, 3, 5, 7, 9, 11 and 13; high-dose Epoetin beta (30.000 IU on days 1, 2 and 3 and placebo on days 5, 7, 9, 11 and 13; or placebo on all days. PMI on days 4, 11 and 25 was determined by interaction of N-acetyl glucosamine with the glycosylation dependent desorption of EPO isoforms. At day 25, plasma-EPO in both rhEPO groups had returned to values not different from the placebo group. PMI with placebo, reflecting the endogenous EPO isoforms, averaged 82.5 (10.3 % (mean (SD. High-dose Epoetin beta decreased PMI on days 4 and 11 to 31.0 (4.2% (p<0.00001 and 45.2 (7.3% (p<0.00001. Low-dose Epoetin beta decreased PMI on days 4 and 11 to 46.0 (12.8% (p<0.00001 and 46.1 (10.4% (p<0.00001. In both rhEPO groups, PMI on day 25 was still decreased (high-dose Epoetin beta: 72.9 (19.4% (p=0.029; low-dose Epoetin beta: 73.1 (17.8% (p=0.039. In conclusion, Epoetin beta leaves a footprint in the plasma-EPO isoform pattern. MAIIA can detect changes in EPO isoform distribution up til at least three weeks after administration of Epoetin beta even though the total EPO concentration has returned to normal.

  11. The effect of erythropoietin on platelet function and fibrinolysis in chronic renal failure

    DEFF Research Database (Denmark)

    Stenver, Doris Irene; Jeppesen, L; Nielsen, B

    1994-01-01

    The influence of erythropoietin therapy on platelet function and fibrinolysis was evaluated in 12 anemic hemodialysis patients. Six months of therapy with human erythropoietin (50 to 80 IU/kg initially) raised the hemoglobin level to 10.8 g/dl but did not increase platelet activity in vivo as mea...

  12. The effect of erythropoietin on platelet function and fibrinolysis in chronic renal failure

    DEFF Research Database (Denmark)

    Stenver, Doris Irene; Jeppesen, L; Nielsen, B

    1994-01-01

    The influence of erythropoietin therapy on platelet function and fibrinolysis was evaluated in 12 anemic hemodialysis patients. Six months of therapy with human erythropoietin (50 to 80 IU/kg initially) raised the hemoglobin level to 10.8 g/dl but did not increase platelet activity in vivo...

  13. Prognostic value of plasma erythropoietin on mortality in patients with chronic heart failure

    NARCIS (Netherlands)

    Van der Meer, P.; Voors, Adriaan; Lipsic, Erik; Smilde, Tom; van Gilst, W.H.; Van Veldhuisen, D.J.

    2004-01-01

    Objectives This study aimed to investigate the prognostic importance of plasma erythropoietin (EPO) levels in chronic heart failure (CHF) patients. Background Anemia is common and is associated with an impaired survival in patients with CHF. Erythropoietin is a hematopoietic growth factor,

  14. HIF-1α inhibition by siRNA or chetomin in human malignant glioma cells: effects on hypoxic radioresistance and monitoring via CA9 expression

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    Bache Matthias

    2010-11-01

    Full Text Available Abstract Background Hypoxia induces activation of the HIF-1 pathway and is an essential characteristic of malignant gliomas. Hypoxia has been linked to tumor progression, therapy resistance and poor prognosis. However, little is known about the impact of HIF-1α inhibition on radioresistance of malignant glioma. Methods In this study, we investigated the effects of the inhibition of HIF-1α on cell survival and radiosensitivity in U251MG and U343MG glioma cells, using two different strategies. HIF-1α inhibition was achieved by siRNA targeting of HIF-1α or via chetomin, a disruptor of interactions between HIF-1α and p300. The inhibition of the HIF-1 pathway was monitored by quantitative real-time PCR and Western blot analyses of the expression levels of HIF-1α and CA9. CA9 expression was investigated as a potential indicator of the efficacy of HIF-1 inhibition and the resulting radiosensitivity of malignant glioma cell lines was determined by clonogenic assay after irradiation under normoxic (2-10 Gy or hypoxic (2-15 Gy conditions. Results Although siRNA and chetomin show distinct modes of action, both attenuated the hypoxia-induced radioresistance of malignant glioma cell lines U251MG (DMF10: 1.35 and 1.18 and U343MG (DMF10: 1.78 and 1.48. However, siRNA and chetomin showed diverse effects on radiosensitivity under normoxic conditions in U251MG (DMF10: 0.86 and 1.35 and U343MG (DMF10: 1.33 and 1.02 cells. Conclusions Results from this in vitro study suggest that inhibition of HIF-1α is a promising strategy to sensitize human malignant gliomas to radiotherapy and that CA9 could serve as an indicator of effective HIF-1-related radiosensitization.

  15. Autocrine VEGF isoforms differentially regulate endothelial cell behavior

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    Hideki Yamamoto

    2016-09-01

    Full Text Available Vascular endothelial growth factor A (VEGF is involved in all the essential biology of endothelial cells, from proliferation to vessel function, by mediating intercellular interactions and monolayer integrity. It is expressed as three major alternative spliced variants. In mice, these are VEGF120, VEGF164, and VEGF188, each with different affinities for extracellular matrices and cell surfaces, depending on the inclusion of heparin-binding sites, encoded by exons 6 and 7. To determine the role of each VEGF isoform in endothelial homeostasis, we compared phenotypes of primary endothelial cells isolated from lungs of mice expressing single VEGF isoforms in normoxic and hypoxic conditions. The differential expression and distribution of VEGF isoforms affect endothelial cell functions, such as proliferation, adhesion, migration and integrity, which are dependent on the stability of and affinity to VEGF receptor 2 (VEGFR2. We found a correlation between autocrine VEGF164 and VEGFR2 stability, which is also associated with increased expression of proteins involved in cell adhesion. Endothelial cells expressing only VEGF188, which localizes to extracellular matrices or cell surfaces, presented a mesenchymal morphology and weakened monolayer integrity. Cells expressing only VEGF120 lacked stable VEGFR2 and dysfunctional downstream processes, rendering the cells unviable. Endothelial cells expressing these different isoforms in isolation also had differing rates of apoptosis, proliferation, and signaling via nitric oxide (NO synthesis. These data indicate that autocrine signaling of each VEGF isoform has unique functions on endothelial homeostasis and response to hypoxia, due to both distinct VEGF distribution and VEGFR2 stability, which appears to be, at least partly, affected by differential NO production. This study demonstrates that each autocrine VEGF isoform has a distinct effect on downstream functions, namely VEGFR2-regulated endothelial cell

  16. Asymmetric Dimethylarginine Contributes to the Impaired Response to Erythropoietin in CKD-Anemia.

    Science.gov (United States)

    Yokoro, Miyuki; Nakayama, Yosuke; Yamagishi, Sho-Ichi; Ando, Ryotaro; Sugiyama, Miki; Ito, Sakuya; Yano, Junko; Taguchi, Kensei; Kaida, Yusuke; Saigusa, Daisuke; Kimoto, Masumi; Abe, Takaaki; Ueda, Seiji; Fukami, Kei

    2017-09-01

    Erythropoietin-resistant anemia is associated with adverse cardiovascular events in patients with ESRD, but the underlying mechanism remains unclear. Here, we evaluated the role of the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA). In 54 patients with advanced CKD, erythrocyte but not plasma ADMA levels independently associated with low hemoglobin values, although levels of both types of ADMA were elevated compared with those in healthy volunteers. Furthermore, erythrocyte ADMA level associated with the erythropoietin resistance index in patients receiving a weekly injected dose of erythropoiesis-stimulating agents standardized for hemoglobin levels and body weight, whereas it correlated with the erythropoietin demand index (plasma erythropoietin units divided by the hemoglobin value) in patients not receiving erythropoiesis-stimulating agents. Compared with sham-operated controls, wild-type mice with 5/6 subtotal nephrectomy (Nx), a remnant kidney model with advanced CKD, had decreased hemoglobin, hematocrit, and mean corpuscular volume values but increased erythrocyte and plasma ADMA and plasma erythropoietin levels. In comparison, dimethylarginine dimethlaminohydrolase-1 transgenic (DDAH-1 Tg) mice, which efficiently metabolized ADMA, had significant improvements in all of the values except those for erythropoietin after 5/6 Nx. Additionally, wild-type Nx mice, but not DDAH-1 Tg Nx mice, had reduced splenic gene expression of erythropoietin receptor and erythroferrone, which regulates iron metabolism in response to erythropoietin. This study suggests that erythrocyte ADMA accumulation contributes to impaired response to erythropoietin in predialysis patients and advanced CKD mice via suppression of erythropoietin receptor expression. Copyright © 2017 by the American Society of Nephrology.

  17. Erythropoietin and the use of a transgenic model of erythropoietin-deficient mice

    Directory of Open Access Journals (Sweden)

    Pichon A

    2016-04-01

    Full Text Available Aurélien Pichon,1–3 Florine Jeton,1,2 Raja El Hasnaoui-Saadani,4 Luciana Hagström,5 Thierry Launay,6 Michèle Beaudry,1 Dominique Marchant,1 Patricia Quidu,1 Jose-Luis Macarlupu,7 Fabrice Favret,8 Jean-Paul Richalet,1,2 Nicolas Voituron1,2 1Laboratory “Hypoxia and Lung” EA 2363, University Paris 13, Sorbonne Paris Cité, Bobigny Cedex, 2Laboratory of Excellence GR-Ex, Paris, 3Laboratory MOVE EA 6314, FSS, Poitiers University, Poitiers, France; 4Research Unit, College of Medicine, Princess Noura University, Riyadh, Saudi Arabia; 5Laboratório Interdisciplinar de Biociências, Universidade de Brasília, Brasília, Brazil; 6Unité de Biologie Intégrative des Adaptations à l'Exercice, University Paris Saclay and Genopole®, University Sorbonne-Paris-Cité, Paris, France; 7High Altitude Unit, Laboratories for Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru; 8Laboratory “Mitochondrie, Stress Oxydant et Protection Musculaire” EA 3072, University of Strasbourg, Strasbourg, France Abstract: Despite its well-known role in red blood cell production, it is now accepted that erythropoietin (Epo has other physiological functions. Epo and its receptors are expressed in many tissues, such as the brain and heart. The presence of Epo/Epo receptors in these organs suggests other roles than those usually assigned to this protein. Thus, the aim of this review is to describe the effects of Epo deficiency on adaptation to normoxic and hypoxic environments and to suggest a key role of Epo on main physiological adaptive functions. Our original model of Epo-deficient (Epo-TAgh mice allowed us to improve our knowledge of the possible role of Epo in O2 homeostasis. The use of anemic transgenic mice revealed Epo as a crucial component of adaptation to hypoxia. Epo-TAgh mice survive well in hypoxic conditions despite low hematocrit. Furthermore, Epo plays a key role in neural control of ventilatory acclimatization and response to

  18. Pazopanib and anti-VEGF therapy

    Directory of Open Access Journals (Sweden)

    Harry A Drabkin

    2010-03-01

    Full Text Available Harry A DrabkinMedical University of South Carolina and Hollings Cancer Center, Charleston, SC, USAAbstract: Pazopanib (VotrientTM, GlaxoSmithKline, a multi-kinase inhibitor with activity against VEGFR and other receptors, was recently approved by the FDA for the treatment of advanced renal cell carcinoma (RCC. Here, we review the history of its development, together with an overview of VEGF and its receptors and co-receptors. Results from selected clinical trial data in RCC and other malignant diseases are presented. Based on available evidence, pazopanib is an effective VEGFR inhibitor with demonstrable clinical activity in metastatic RCC and promising activity in other diseases. Like most kinase inhibitors, its activity is not restricted to VEGF receptors, which is reflected in its side-effect profile.Keywords: pazopanib, VEGFR, renal cell carcinoma

  19. COX-2, VEGF and tumour angiogenesis.

    LENUS (Irish Health Repository)

    Toomey, D P

    2009-06-01

    Epidemiological evidence suggests a protective effective of regular NSAID use against developing cancer. Cyclooxygenase-2, a target of NSAIDs, is upregulated in many cancers and has been associated with increased VEGF production and angiogenesis. Angiogenesis is the formation of new vessels from existing vasculature and as an essential process for tumour development represents an important therapeutic target. Following an extensive review of the literature this article details the current knowledge on the role of COX-2 in tumorigenesis focusing on its relationship to angiogenesis and VEGF production by tumour cells. While COX-2 is clearly detrimental to prognosis and NSAIDs have a beneficial effect, the possibility of COX-2 independent effects being partly or wholly responsible for this benefit cannot be excluded.

  20. Biological evaluation of recombinant human erythropoietin in pharmaceutical products

    Directory of Open Access Journals (Sweden)

    Ramos A.S.

    2003-01-01

    Full Text Available The potencies of mammalian cell-derived recombinant human erythropoietin pharmaceutical preparations, from a total of five manufacturers, were assessed by in vivo bioassay using standardized protocols. Eight-week-old normocythemic mice received a single subcutaneous injection followed by blood sampling 96 h later or multiple daily injections with blood sampling 24 h after the last injection. Reticulocyte counting by microscopic examination was employed as the end-point using the brilliant cresyl blue or selective hemolysis methods, together with automated flow cytometry. Different injection schedules were investigated and dose-response curves for the European Pharmacopoeia Biological Reference Preparation of erythropoietin were compared. Manual and automated methods of reticulocyte counting were correlated with respect to assay validity and precision. Using 8 mice per treatment group, intra-assay precision determined for all of the assays in the study showed coefficients of variation of 12.1-28.4% for the brilliant cresyl blue method, 14.1-30.8% for the selective hemolysis method and 8.5-19.7% for the flow cytometry method. Applying the single injection protocol, a combination of at least two independent assays was required to achieve the precision potency and confidence limits indicated by the manufacturers, while the multiple daily injection protocol yielded the same acceptable results within a single assay. Although the latter protocol using flow cytometry for reticulocyte counting gave more precise and reproducible results (intra-assay coefficients of variation: 5.9-14.2%, the well-characterized manual methods provide equally valid alternatives for the quality control of recombinant human erythropoietin therapeutic products.

  1. Hemopoietic cell precursor responses to erythropoietin in plasma clot cultures

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, W.L.

    1979-01-01

    The time dependence of the response of mouse bone marrow cells to erythropoietin (Ep) in vitro was studied. Experiments include studies on the Ep response of marrow cells from normal, plethoric, or bled mice. Results with normal marrow reveal: (1) Not all erythroid precursors (CFU-E) are alike in their response to Ep. A significant number of the precursors develop to a mature erythroid colony after very short Ep exposures, but they account for only approx. 13% of the total colonies generated when Ep is active for 48 hrs. If Ep is active more than 6 hrs, a second population of erythroid colonies emerges at a nearly constant rate until the end of the culture. Full erythroid colony production requires prolonged exposure to erythropoietin. (2) The longer erythropoietin is actively present, the larger the number of erythroid colonies that reach 17 cells or more. Two distinct populations of immediate erythroid precursors are also present in marrow from plethoric mice. In these mice, total colony numbers are equal to or below those obtained from normal mice. However, the population of fast-responding CFU-E is consistently decreased to 10 to 20% of that found in normal marrow. The remaining colonies are formed from plethoric marrow at a rate equal to normal marrow. With increasing Ep exposures, the number of large colonies produced increases. From the marrow of bled mice, total erythroid colony production is equal to or above that of normal marrow. Two populations of colony-forming cells are again evident, with the fast-responding CFU-E being below normal levels. The lack of colonies from this group was compensated in bled mice by rapid colony production in the second population. A real increase in numbers of precursors present in this pool increased the rate of colony production in culture to twice that of normal marrow. The number of large colonies obtained from bled mice was again increased as the Ep exposure was lengthened. (ERB)

  2. Expression of VEGF(xxx)b, the inhibitory isoforms of VEGF, in malignant melanoma.

    Science.gov (United States)

    Pritchard-Jones, R O; Dunn, D B A; Qiu, Y; Varey, A H R; Orlando, A; Rigby, H; Harper, S J; Bates, D O

    2007-07-16

    Malignant melanoma is the most lethal of the skin cancers and the UK incidence is rising faster than that of any other cancer. Angiogenesis - the growth of new vessels from preexisting vasculature - is an absolute requirement for tumour survival and progression beyond a few hundred microns in diameter. We previously described a class of anti-angiogenic isoforms of VEGF, VEGF(xxx)b, that inhibit tumour growth in animal models, and are downregulated in some cancers, but have not been investigated in melanoma. To determine whether VEGF(xxx)b expression was altered in melanoma, PCR and immunohistochemistry of archived human tumour samples were used. In normal epidermis and in a proportion of melanoma samples, VEGF(xxx)b staining was seen. Some melanomas had much weaker staining. Subsequent examination revealed that expression was significantly reduced in primary melanoma samples (both horizontal and vertical growth phases) from patients who subsequently developed tumour metastasis compared with those who did not (analysis of variance (ANOVA) Pxxx)b expression appears to predict metastatic spread in patients with primary melanoma. These results suggest that there is a switch in splicing as part of the metastatic process, from anti-angiogenic to pro-angiogenic VEGF isoforms. This may form part of a wider metastatic splicing phenotype.

  3. Effects of intraosseous erythropoietin during hemorrhagic shock in swine.

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    Vesna Borovnik-Lesjak

    Full Text Available OBJECTIVE: To determine whether erythropoietin given during hemorrhagic shock (HS ameliorates organ injury while improving resuscitation and survival. METHODS: Three series of 24 pigs each were studied. In an initial series, 50% of the blood volume (BV was removed in 30 minutes and normal saline (threefold the blood removed started at minute 90 infusing each third in 30, 60, and 150 minutes with shed blood reinfused at minute 330 (HS-50BV. In a second series, the same HS-50BV protocol was used but removing an additional 15% of BV from minute 30 to 60 (HS-65BV. In a final series, blood was removed as in HS-65BV and intraosseous vasopressin given from minute 30 (0.04 U/kg min(-1 until start of shed blood reinfusion at minute 150 (HS-65BV+VP. Normal saline was reduced to half the blood removed and given from minute 90 to 120 in half of the animals. In each series, animals were randomized 1:1 to receive erythropoietin (1,200 U/kg or control solution intraosseously after removing 10% of the BV. RESULTS: In HS-50BV, O2 consumption remained near baseline yielding minimal lactate increases, 88% resuscitability, and 60% survival at 72 hours. In HS-65BV, O2 consumption was reduced and lactate increased yielding 25% resuscitability. In HS-65BV+VP, vasopressin promoted hemodynamic stability yielding 92% resuscitability and 83% survival at 72 hours. Erythropoietin did not affect resuscitability or subsequent survival in any of the series but increased interleukin-10, attenuated lactate increases, and ameliorated organ injury based on lesser troponin I, AST, and ALT increases and lesser neurological deficits in the HS-65BV+VP series. CONCLUSIONS: Erythropoietin given during HS in swine failed to alter resuscitability and 72 hour survival regardless of HS severity and concomitant treatment with fluids and vasopressin but attenuated acute organ injury. The studies also showed the efficacy of vasopressin and restrictive fluid resuscitation for hemodynamic

  4. High-dose erythropoietin in patients with progressive multiple sclerosis

    DEFF Research Database (Denmark)

    Schreiber, Karen; Magyari, Melinda; Sellebjerg, Finn

    2017-01-01

    BACKGROUND: Erythropoietin (EPO) is a part of an endogenous neuroprotective system in the brain and may address pathophysiological mechanisms in progressive multiple sclerosis (MS). OBJECTIVE: To evaluate a treatment effect of EPO on progressive MS. METHODS: This was a single-center, randomized......, double-blind, placebo-controlled phase 2 trial, in which 52 patients with secondary or primary progressive MS were allocated to treatment with recombinant EPO (48,000 IU) or placebo, administered intravenously 17 times during 24 weeks. Patients had an Expanded Disability Status Score (EDSS) from 4 to 6...

  5. Novel red-emitting phosphor Ca9Y(PO4)7:Ce3+,Mn2+ with energy transfer for fluorescent lamp application.

    Science.gov (United States)

    Huang, Chien-Hao; Kuo, Te-Wen; Chen, Teng-Ming

    2010-05-01

    A series of new luminescent emission-tunable phosphors Ca(9)Y(PO(4))(7):zCe(3+),xMn(2+) have been synthesized by a high-temperature solid-state reaction. We report a broad deep red-emitting composition-optimized phosphor (Ca(0.9))(9)Y(0.85)(PO(4))(7):0.15Ce(3+),0.1Mn(2+), which has been found to be feasible for the application in fluorescent lamps. The Commission Internationale de I'Eclairage (CIE) chromaticity coordinates measured for the phosphor were (0.68, 0.29), and those for fluorescent lamps with and without a 600 nm filter were found to be (0.67, 0.29) and (0.54, 0.32), respectively. The Ca(9)Y(PO(4))(7):Ce(3+),Mn(2+) phosphor showed two emission bands under 254 nm excitation: the one observed at 366 nm was attributed to Ce(3+) ion emission, and the other found at 650 nm was assigned to the emission from Mn(2+) ions. We have shown that the mechanism of energy transfer from Ce(3+) to Mn(2+) was of the resonance type and it occurred via an electric dipole-quadrupole interaction. Furthermore, we have calculated the critical distance for Ce(3+) --> Mn(2+) energy transfer to be 13.45 A by concentration quenching methods.

  6. VEGF Expression in Patellar Tendinopathy: A Preliminary Study

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    Lian, Øystein; Bahr, Roald; Hart, David A.; Duronio, Vincent

    2008-01-01

    Vascular function and angiogenesis are regulated by vascular endothelial growth factor-A (VEGF). The purpose of this preliminary study was to address the following questions: Is VEGF expression in the patellar tendon more prevalent in patients with patellar tendinopathy than in individuals with normal, pain-free patellar tendons? Which cell populations express VEGF in normal and tendinopathic tendon? Is there a difference in symptom duration between VEGF+ and VEGF− tendons? We collected patellar tendon tissue from 22 patients undergoing open débridement of the patellar tendon and from 10 patients undergoing intramedullary nailing of the tibia. VEGF expression was assessed immunohistochemically. Relevant inflammatory and repair cell types were immunolabeled. VEGF expression was absent from control tendons, but was present in a subset of patients with histopathological evidence of angiofibroblastic tendinosis. VEGF was expressed in the intimal layer of tendon vessels, but was absent in other cell types. Patients demonstrating VEGF expression in the patellar tendon had a shorter symptom duration (12 ± 7.8 months) than patients with no detectable VEGF (32.8 ± 23.5 months). VEGF may contribute to the vascular hyperplasia that is a cardinal feature of symptomatic tendinosis, particularly in cases with more recent onset. PMID:18459027

  7. Comparative integromics on VEGF family members.

    Science.gov (United States)

    Katoh, Yuriko; Katoh, Masaru

    2006-06-01

    VEGF, Hedgehog, FGF, Notch, and WNT signaling pathways network together for vascular remodeling during embryogenesis, tissue regeneration, and carcinogenesis. VEGFA (VEGF), VEGFB, VEGFC, VEGFD (FIGF) and PGF (PlGF) are VEGF family ligands for receptor tyrosine kinases, including VEGFR1 (FLT1), VEGFR2 (KDR) and VEGFR3 (FLT4). Bevacizumab (Avastin), Sunitinib (Sutent) and Sorafenib (Nexavar) are anti-cancer drugs targeted to VEGF signaling pathway. TCF/LEF binding sites within the promoter region of human VEGF family members were searched for by using bioinformatics and human intelligence (Humint). Because four TCF/LEF-binding sites were identified within the 5'-promoter region of human VEGFD gene within AC095351.5 genome sequence, comparative genomics analyses on VEGFD orthologs were further performed. ASB9-ASB11-VEGFD locus at human chromosome Xp22.2 and ASB5-VEGFC locus at human chromosome 4q34 were paralogous regions within the human genome. Human VEGFD mRNA was expressed in lung, small intestine, uterus, breast, neural tissues, and neuroblastoma. Mouse Vegfd mRNA was expressed in kidney, pregnant oviduct, and neural tissues. Chimpanzee VEGFD promoter, cow Vegfd promoter, mouse Vegfd promoter and rat Vegfd promoter were identified within NW_121675.1, AC161065.2, AL732475.6 and AC130036.3 genome sequences, respectively. Three out of four TCF/LEF-binding sites within human VEGFD promoter were conserved in chimpanzee VEGFD promoter, and one in cow Vegfd promoter. TCF/LEF-binding site, not conserved in human VEGFD promoter, occurred in cow, mouse and rat Vegfd promoters. At least five out of six bHLH-binding sites within human VEGFD proximal promoter region were conserved in chimpanzee VEGFD proximal promoter region, while only one in cow Vegfd proximal promoter region. Together these facts indicate that relatively significant promoter evolution occurred among mammalian VEGFD orthologs. Human VEGFD was characterized as a potent target gene of WNT

  8. [VEGF as an angiogenic, neurotrophic, and neuroprotective factor].

    Science.gov (United States)

    Namiecińska, Magdalena; Marciniak, Katarzyna; Nowak, Jerzy Z

    2005-01-01

    Vascular endothelial growth factor (VEGF, occurring in several isoforms: VEGF-A, -B, -C, -D) is a well-known endothelial cell mitogen and vascular growth and permeability factor. Recent work done over the last few years has elucidated the important role of VEGF, which participates in the regulation of normal (physiological or therapeutic) and pathological angiogenesis (VEGF-A, VEGF-B) and lymphangiogenesis (VEGF-C, VEGF-D). VEGF has also been implicated in practically every stage of angiogenesis, yet its role in the initiation of new blood vessel creation appears to be the most important. In addition to its role as a key angiogenic factor, VEGF also possesses neurotrophic and neuroprotective activity both in the peripheral and in the central nervous system, exerting a direct action on neurons, Schwann cells, astrocytes, neural stem cells, and microglia. VEGF interacts with three subtypes of VEGF receptors occurring on the cellular membrane known as VEGFR-1 (Flt-1), VEGFR-2 (Flk-1/KDR), and VEGFR-3 (Flt-4). All these receptor types possess an internal tyrosin kinase domain. Interaction of VEGF with particular subtypes of receptors activates a circuit of signaling pathways, e.g. PI3K/Akt, Ras/Raf-MEK/Erk, eNOS/NO, and IP3/Ca2+. These participate in the generation of specific biological responses connected with proliferation, migration, increasing vascular permeability, or promoting endothelial cell survival. Recent findings from experiments performed on animals with experimentally evoked focal cerebral ischemia suggest that the neuroprotective activity of VEGF runs in parallel with its ability to promote neurogenesis and angiogenesis and that these effects may operate independently through multiple mechanisms. The above-mentioned three major features characterizing the neurobiological activity of VEGF, i.e. neuroprotection, neurogenesis, and angiogenesis, together with their possible functional link(s), provide the rationale for considering VEGF-based therapy as a

  9. Impaired angiogenesis and endochondral bone formation in mice lacking the vascular endothelial growth factor isoforms VEGF164 and VEGF188.

    Science.gov (United States)

    Maes, Christa; Carmeliet, Peter; Moermans, Karen; Stockmans, Ingrid; Smets, Nico; Collen, Désiré; Bouillon, Roger; Carmeliet, Geert

    2002-02-01

    Vascular endothelial growth factor (VEGF)-mediated angiogenesis is an important part of bone formation. To clarify the role of VEGF isoforms in endochondral bone formation, we examined long bone development in mice expressing exclusively the VEGF120 isoform (VEGF120/120 mice). Neonatal VEGF120/120 long bones showed a completely disturbed vascular pattern, concomitant with a 35% decrease in trabecular bone volume, reduced bone growth and a 34% enlargement of the hypertrophic chondrocyte zone of the growth plate. Surprisingly, embryonic hindlimbs at a stage preceding capillary invasion exhibited a delay in bone collar formation and hypertrophic cartilage calcification. Expression levels of marker genes of osteoblast and hypertrophic chondrocyte differentiation were significantly decreased in VEGF120/120 bones. Furthermore, inhibition of all VEGF isoforms in cultures of embryonic cartilaginous metatarsals, through the administration of a soluble receptor chimeric protein (mFlt-1/Fc), retarded the onset and progression of ossification, suggesting that osteoblast and/or hypertrophic chondrocyte development were impaired. The initial invasion by osteoclasts and endothelial cells into VEGF120/120 bones was retarded, associated with decreased expression of matrix metalloproteinase-9. Our findings indicate that expression of VEGF164 and/or VEGF188 is important for normal endochondral bone development, not only to mediate bone vascularization but also to allow normal differentiation of hypertrophic chondrocytes, osteoblasts, endothelial cells and osteoclasts.

  10. Erythropoietin improves operant conditioning and stability of cognitive performance in mice

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    Ehrenreich Hannelore

    2009-07-01

    Full Text Available Abstract Background Executive functions, learning and attention are imperative facets of cognitive performance, affected in many neuropsychiatric disorders. Recently, we have shown that recombinant human erythropoietin improves cognitive functions in patients with chronic schizophrenia, and that it leads in healthy mice to enhanced hippocampal long-term potentiation, an electrophysiological correlate of learning and memory. To create an experimental basis for further mechanistic insight into erythropoietin-modulated cognitive processes, we employed the Five Choice Serial Reaction Time Task. This procedure allows the study of the effects of erythropoietin on discrete processes of learning and attention in a sequential fashion. Results Male mice were treated for 3 weeks with erythropoietin (5,000 IU/kg versus placebo intraperitoneally every other day, beginning at postnatal day 28. After termination of treatment, mice were started on the Five Choice Serial Reaction Time Task, with daily training and testing extending to about 3 months. Overall, a significantly higher proportion of erythropoietin-treated mice finished the task, that is, reached the criteria of adequately reacting to a 1.0 sec flash light out of five arbitrarily appearing choices. During acquisition of this capability, that is, over almost all sequential training phases, learning readouts (magazine training, operant and discriminant learning, stability of performance were superior in erythropoietin-treated versus control mice. Conclusion Early erythropoietin treatment leads to lasting improvement of cognitive performance in healthy mice. This finding should be exploited in novel treatment strategies for brain diseases.

  11. Pharmacological Effects of Erythropoietin and its Derivative Carbamyl erythropoietin in Cerebral White Matter Injury

    Science.gov (United States)

    Liu, Wei

    Periventricular leukomalacia (PVL) is the predominant form of brain injury in the premature infant and the most common cause of cerebral palsy, yet no therapy currently exists for this serious human disorder. As PVL often occurs in preterm infants suffering from cerebral hypoxia/ischemia with or without prior exposure to maternal-fetal infection/inflammation, we used hypoxia/ischemia with or without lipopolysaccharide (LPS) injection, to produce clinically relevant PVL-like lesions in the white matter in postnatal day six (P6) mice. We studied the white matter pathology under different conditions, such as different durations of hypoxia and different doses of LPS, to evaluate the effects of those etiological factors on neonatal white matter injury. Distinct related pathological events were investigated at different time points during the progression of PVL. We used immunohistochemistry, histological analysis, and electron microscopy (EM) to study demylination that occurs in the white matter area, which is consistent with the pathology of human PVL. Previous studies have shown that erythropoietin (EPO) and its derivative carbamylated EPO (CEPO) are neuroprotective in various experimental models of brain injury. However, none of these studies investigated their efficacy against white matter injury using appropriate animal models of PVL. We produced unilateral or bilateral white matter injury in P6 mice using unilateral carotid ligation (UCL) followed by hypoxia (6% oxygen, 35 min) or by UCL/hypoxia plus LPS injection, respectively. We administered a single intraperitoneal (i.p.) dose of EPO or CEPO (5000 IU/kg) immediately after the insult, and found both drugs to provide significant protection against white matter injury in PVL mice compared to vehicle-treated groups. In addition, EPO and CEPO treatments attenuated neurobehavioral dysfunctions in an acute manner after PVL injury. EPO and CEPO have relatively few adverse effects, and thus may be a therapeutic agent

  12. Anti-VEGF Therapy for Diabetic Eye Diseases.

    Science.gov (United States)

    Bahrami, Bobak; Hong, Thomas; Gilles, Mark C; Chang, Andrew

    2017-01-01

    Diabetic retinopathy (DR) is a leading cause of vision impairment and blindness in the working-age population. The identification of vascular endothelial growth factor (VEGF) as a key mediator in the pathogenesis of DR has revolutionized the management of this vision-threatening disease. There is now strong evidence supporting intravitreal anti-VEGF therapy as first line in the management of sight-threatening diabetic macular edema (DME), along with a growing body of evidence to support the use of anti-VEGF drugs for proliferative DR. This review summarizes the role of VEGF in DR, the evidence for anti-VEGF therapy, safety considerations, and the future of anti-VEGF therapy for the management of DR. Copyright 2017 Asia-Pacific Academy of Ophthalmology.

  13. Erythropoietin inhibits osteoblast function in myelodysplastic syndromes via the canonical Wnt pathway.

    Science.gov (United States)

    Balaian, Ekaterina; Wobus, Manja; Weidner, Heike; Baschant, Ulrike; Stiehler, Maik; Ehninger, Gerhard; Bornhäuser, Martin; Hofbauer, Lorenz C; Rauner, Martina; Platzbecker, Uwe

    2018-01-01

    The effects of erythropoietin on osteoblasts and bone formation are controversial. Since patients with myelodysplastic syndromes often display excessively high erythropoietin levels, we aimed to analyze the effect of erythropoietin on osteoblast function in myelodysplastic syndromes and define the role of Wnt signaling in this process. Expression of osteoblast-specific genes and subsequent osteoblast mineralization was increased in mesenchymal stromal cells from healthy young donors by in vitro erythropoietin treatment. However, erythropoietin failed to increase osteoblast mineralization in old healthy donors and in patients with myelodysplasia, whereas the basal differentiation potential of the latter was already significantly reduced compared to that of age-matched controls ( P <0.01). This was accompanied by a significantly reduced expression of genes of the canonical Wnt pathway. Treatment of these cells with erythropoietin further inhibited the canonical Wnt pathway. Exposure of murine cells (C2C12) to erythropoietin also produced a dose-dependent inhibition of TCF/LEF promoter activity (maximum at 500 IU/mL, -2.8-fold; P <0.01). The decreased differentiation capacity of erythropoietin-pretreated mesenchymal stromal cells from patients with myelodysplasia could be restored by activating the Wnt pathway using lithium chloride or parathyroid hormone. Its hematopoiesis-supporting capacity was reduced, while reactivation of the canonical Wnt pathway in mesenchymal stromal cells could reverse this effect. Thus, these data demonstrate that erythropoietin modulates components of the osteo-hematopoietic niche in a context-dependent manner being anabolic in young, but catabolic in mature bone cells. Targeting the Wnt pathway in patients with myelodysplastic syndromes may be an appealing strategy to promote the functional capacity of the osteo-hematopoietic niche. Copyright© 2018 Ferrata Storti Foundation.

  14. Engineered microenvironments for synergistic VEGF - Integrin signalling during vascularization.

    Science.gov (United States)

    Moulisová, Vladimíra; Gonzalez-García, Cristina; Cantini, Marco; Rodrigo-Navarro, Aleixandre; Weaver, Jessica; Costell, Mercedes; Sabater I Serra, Roser; Dalby, Matthew J; García, Andrés J; Salmerón-Sánchez, Manuel

    2017-05-01

    We have engineered polymer-based microenvironments that promote vasculogenesis both in vitro and in vivo through synergistic integrin-growth factor receptor signalling. Poly(ethyl acrylate) (PEA) triggers spontaneous organization of fibronectin (FN) into nanonetworks which provide availability of critical binding domains. Importantly, the growth factor binding (FNIII12-14) and integrin binding (FNIII9-10) regions are simultaneously available on FN fibrils assembled on PEA. This material platform promotes synergistic integrin/VEGF signalling which is highly effective for vascularization events in vitro with low concentrations of VEGF. VEGF specifically binds to FN fibrils on PEA compared to control polymers (poly(methyl acrylate), PMA) where FN remains in a globular conformation and integrin/GF binding domains are not simultaneously available. The vasculogenic response of human endothelial cells seeded on these synergistic interfaces (VEGF bound to FN assembled on PEA) was significantly improved compared to soluble administration of VEGF at higher doses. Early onset of VEGF signalling (PLCγ1 phosphorylation) and both integrin and VEGF signalling (ERK1/2 phosphorylation) were increased only when VEGF was bound to FN nanonetworks on PEA, while soluble VEGF did not influence early signalling. Experiments with mutant FN molecules with impaired integrin binding site (FN-RGE) confirmed the role of the integrin binding site of FN on the vasculogenic response via combined integrin/VEGF signalling. In vivo experiments using 3D scaffolds coated with FN and VEGF implanted in the murine fat pad demonstrated pro-vascularization signalling by enhanced formation of new tissue inside scaffold pores. PEA-driven organization of FN promotes efficient presentation of VEGF to promote vascularization in regenerative medicine applications. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Hypoxia promotes adipose-derived stem cell proliferation via VEGF

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    Phuc Van Pham

    2016-01-01

    Full Text Available Adipose-derived stem cells (ADSCs are a promising mesenchymal stem cell source with therapeutic applications. Recent studies have shown that ADSCs could be expanded in vitro without phenotype changes. This study aimed to evaluate the effect of hypoxia on ADSC proliferation in vitro and to determine the role of vascular endothelial growth factor (VEGF in ADSC proliferation. ADSCs were selectively cultured from the stromal vascular fraction obtained from adipose tissue in DMEM/F12 medium supplemented with 10% fetal bovine serum and 1% antibiotic-antimycotic. ADSCs were cultured under two conditions: hypoxia (5% O2 and normal oxygen (21% O2. The effects of the oxygen concentration on cell proliferation were examined by cell cycle and doubling time. The expression of VEGF was evaluated by the ELISA assay. The role of VEGF in ADSC proliferation was studied by neutralizing VEGF with anti-VEGF monoclonal antibodies. We found that the ADSC proliferation rate was significantly higher under hypoxia compared with normoxia. In hypoxia, ADSCs also triggered VEGF expression. However, neutralizing VEGF with anti-VEGF monoclonal antibodies significantly reduced the proliferation rate. These results suggest that hypoxia stimulated ADSC proliferation in association with VEGF production. [Biomed Res Ther 2016; 3(1.000: 476-482

  16. Molecular Imaging of VEGF Receptors in Graft Arteriosclerosis

    Science.gov (United States)

    Zhang, Jiasheng; Razavian, Mahmoud; Tavakoli, Sina; Nie, Lei; Tellides, George; Backer, Joseph M.; Backer, Marina V.; Bender, Jeffrey R.; Sadeghi, Mehran M.

    2012-01-01

    Objectives Vascular endothelial growth factor (VEGF) signaling plays a key role in the pathogenesis of vascular remodeling, including graft arteriosclerosis (GA). GA is the major cause of late organ failure in cardiac transplantation. We used molecular near-infrared fluorescent (NIRF) imaging with an engineered Cy5.5-labeled single-chain VEGF tracer (scVEGF/Cy) to detect VEGF receptors (VEGFRs) and vascular remodeling in human coronary artery grafts by molecular imaging. Methods and Results VEGFR-specificity of probe uptake was shown by flow cytometry in endothelial cells. In severe combined immunodeficiency mice, transplantation of human coronary artery segments into the aorta followed by adoptive transfer of allogeneic human peripheral blood mononuclear cells (PBMCs) led to significant neointima formation in the grafts over a period of 4 weeks. NIRF imaging of transplant recipients at 4 weeks demonstrated focal uptake of scVEGF/Cy in remodeling artery grafts. Uptake specificity was demonstrated using an inactive homologue of scVEGF/Cy. scVEGF/Cy uptake predominantly localized in the neointima of remodeling coronary arteries and correlated with VEGFR-1, but not VEGFR-2 expression. There was a significant correlation between scVEGF/Cy uptake and transplanted artery neointima area. Conclusions Molecular imaging of VEGF receptors may provide a non-invasive tool for detection of GA in solid organ transplantation. PMID:22723442

  17. Taiwan cobra cardiotoxin III inhibits Src kinase leading to apoptosis and cell cycle arrest of oral squamous cell carcinoma Ca9-22 cells.

    Science.gov (United States)

    Chien, Ching-Ming; Chang, Shang-Yu; Lin, Kuei-Li; Chiu, Chien-Chih; Chang, Long-Sen; Lin, Shinne-Ren

    2010-09-15

    Cardiotoxin III (CTX III), a basic polypeptide with 60-amino acid residues isolated from Naja naja atra venom, has been reported to have cytotoxic activity. CTX III exerted cytotoxicity with the S-phase cell cycle arrest, correlated with a marked decrease in the expression levels of cyclin A, cyclin B, and cyclin-dependent kinase 1 (CDK1), and apoptosis, accompanied with Bax and Bad up-regulation, and the down-regulation of Bcl-2, p-Bad, and X-linked inhibitor of apoptosis (XIAP) with cytochrome c release and sequential activation of caspase-9 and caspase-3 in Ca9-22 cells. Mechanistic studies showed that CTX III suppressed the phosphorylation of Src, EGFR, STAT3, STAT5, Akt, and activation of PI3 K (p110). Moreover, Src inactivation was observed earlier than that of the EGFR and the Src inhibitor PP2 suppressed the levels of phospho-EGFR, phospho-STAT3, phospho-STAT5, phospho-Akt, and PI3 K(p110). The PP2 also caused the S-phase arrest and apoptosis, and led to down-regulation of Bcl-2, p-Bad, XIAP, cyclin A, cyclin B, and CDK1, and up-regulation of Bax and Bad, similar to that observed in CTX III treatment. Taken together, these results indicate that CTX III induces apoptosis and S-phase arrest in Ca9-22 cells via concomitant inactivation of the Src, EGFR, STAT3, STAT5, PI3 K(p110), and Akt signaling pathways. Copyright 2010 Elsevier Ltd. All rights reserved.

  18. Novel VEGF decoy receptor fusion protein conbercept targeting multiple VEGF isoforms provide remarkable anti-angiogenesis effect in vivo.

    Directory of Open Access Journals (Sweden)

    Qin Wang

    Full Text Available VEGF family factors are known to be the principal stimulators of abnormal angiogenesis, which play a fundamental role in tumor and various ocular diseases. Inhibition of VEGF is widely applied in antiangiogenic therapy. Conbercept is a novel decoy receptor protein constructed by fusing VEGF receptor 1 and VEGF receptor 2 extracellular domains with the Fc region of human immunoglobulin. In this study, we systematically evaluated the binding affinity of conbercept with VEGF isoforms and PlGF by using anti-VEGF antibody (Avastin as reference. BIACORE and ELISA assay results indicated that conbercept could bind different VEGF-A isoforms with higher affinity than reference. Furthermore, conbercept could also bind VEGF-B and PlGF, whereas Avastin showed no binding. Oxygen-induced retinopathy model showed that conbercept could inhibit the formation of neovasularizations. In tumor-bearing nude mice, conbercept could also suppress tumor growth very effectively in vivo. Overall, our study have demonstrated that conbercept could bind with high affinity to multiple VEGF isoforms and consequently provide remarkable anti-angiogenic effect, suggesting the possibility to treat angiogenesis-related diseases such as cancer and wet AMD etc.

  19. La eritropoyetina un neuroprotector potencial Erythropoietin: A potential neuroreceptor

    Directory of Open Access Journals (Sweden)

    Alain Valdivia Acosta

    2007-08-01

    Full Text Available La importante función fisiológica de la hormona eritropoyetina en el proceso eritropoyético se descubrió hace alrededor de un siglo. Mas recientemente se ha trabajado en su obtención por vía recombinante para su aplicación en pacientes con anemias agudas o crónicas, causadas por diferentes afecciones. Esta terapia mejora, sin lugar a duda, la calidad de vida de estos pacientes. A partir del año 1998, se reportaron por primera vez las propiedades neuroprotectoras de la eritropoyetina y se realizaron estudios que así lo corroboraron con el empleo de modelos de daño cerebral, tanto in vitro como in vivo. Los estudios actuales consisten en dilucidar a profundidad los mecanismos de acción por los cuales la eritropoyetina muestra sus propiedades neuroprotectoras y en obtener una adecuada biodisponibildad de la molécula para su aplicación segura en la terapéutica de afecciones del cerebro. El presente trabajo recopila información actualizada sobre la eritropoyetina como agente neuroprotector y refiere la continuidad de estudios para su aplicación en la clínica.A century ago, significant physiolgical function of Erithropoietin was discovered. More recently, it has been working on its obtention by a recombinant via for application in patients presenting with acute and chronic anemia, from different afections. This type of therapy improves undoubtedly, life quality of these patients. From 1998, neuroprotective properties of Erythropoietin were retorted for the first time, and we performed studies corroborating it b y means of use of bran damage model, both, in vitro and in vivo. Present studies are designed to elucidate deeply action mechanisms by which Erythropoietin shows its neuroprotective properties and to obtain a appropriate bioavailability of molecule for a accurate application in therapeutics of bran afections. Present paper collets updated information on Erythropoietin as a neuroprotective agent, and refers to continuity of

  20. Pancreatic duct cells as a source of VEGF in mice.

    Science.gov (United States)

    Xiao, Xiangwei; Prasadan, Krishna; Guo, Ping; El-Gohary, Yousef; Fischbach, Shane; Wiersch, John; Gaffar, Iljana; Shiota, Chiyo; Gittes, George K

    2014-05-01

    Vascular endothelial growth factor (VEGF) is essential for proper pancreatic development, islet vascularisation and insulin secretion. In the adult pancreas, VEGF is thought to be predominantly secreted by beta cells. Although human duct cells have previously been shown to secrete VEGF at angiogenic levels in culture, an analysis of the kinetics of VEGF synthesis and secretion, as well as elucidation of an in vivo role for this ductal VEGF in affecting islet function and physiology, has been lacking. We analysed purified duct cells independently prepared by flow cytometry, surgical isolation or laser-capture microdissection. We infected duct cells in vivo with Vegf (also known as Vegfa) short hairpin RNA (shRNA) in an intrapancreatic ductal infusion system and examined the effect of VEGF knockdown in duct cells in vitro and in vivo. Pancreatic duct cells express high levels of Vegf mRNA. Compared with beta cells, duct cells had a much higher ratio of secreted to intracellular VEGF. As a bioassay, formation of tubular structures by human umbilical vein endothelial cells was essentially undetectable when cultured alone and was substantially increased when co-cultured with pancreatic duct cells but significantly reduced when co-cultured with duct cells pretreated with Vegf shRNA. Compared with islets transplanted alone, improved vascularisation and function was detected in the islets co-transplanted with duct cells but not in islets co-transplanted with duct cells pretreated with Vegf shRNA. Human islet preparations for transplantation typically contain some contaminating duct cells and our findings suggest that the presence of duct cells in the islet preparation may improve transplantation outcomes.

  1. Identification and characterization of VEGF and FGF from Hydra.

    Science.gov (United States)

    Krishnapati, Lakshmi-Surekha; Ghaskadbi, Surendra

    2013-01-01

    Vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) play important roles in the formation of the blood vascular system and in axon guidance, nervous system development and function. Here, we report isolation and characterization of VEGF and FGF homologues from Hydra vulgaris Ind-Pune, a Cnidarian which exhibits an organized nervous system and primitive epithelio-muscular cells. VEGF expression was prominent in the endoderm of the peduncle region and tentacles, as evident from in situ hybridization of whole polyps and its transverse sections. High levels of FGF were detected in the ectoderm of the budding region. The expression of VEGF in endodermal and FGF in interstitial cells was confirmed using sf-1 hydra, a temperature-sensitive mutant strain of Hydra magnipapillata. Tissue-specific expression of VEGF and FGF was confirmed by semi quantitative RT-PCR for ectodermal and endodermal tissues in H. vulgaris Ind-Pune. Treatment with SU5416, a specific inhibitor of the VEGF receptor, did not affect the whole polyp, but did delay both budding and head regeneration, suggesting a possible role of VEGF in nerve cell development, tube formation and/or in branching. FGF expression in the ectoderm of budding region, where the majority of interstitial stem cells reside suggests its role in interstitial stem cell maintenance. Further, activation of canonical Wnt signalling with the glycogen synthase kinase-3β (GSK-3β) inhibitor alsterpaullone caused down-regulation of VEGF and FGF, suggesting an antagonistic relationship between the Wnt and VEGF/FGF pathways. Our results indicate that VEGF and FGF evolved early in evolution, before the development of the blood vascular system, and open up the possibility of elucidating the evolutionarily ancient functions of VEGF and FGF.

  2. Plasmodium berghei ANKA: erythropoietin activates neural stem cells in an experimental cerebral malaria model

    DEFF Research Database (Denmark)

    Core, Andrew; Hempel, Casper; Kurtzhals, Jørgen A L

    2011-01-01

    Cerebral malaria (CM) causes substantial mortality and neurological sequelae in survivors, and no neuroprotective regimens are currently available for this condition. Erythropoietin (EPO) reduces neuropathology and improves survival in murine CM. Using the Plasmodium berghei model of CM, we...

  3. Aberrant, ectopic expression of VEGF and VEGF receptors 1 and 2 in malignant colonic epithelial cells. Implications for these cells growth via an autocrine mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Ahluwalia, Amrita [Veterans Affairs Long Beach Healthcare System, Long Beach, CA (United States); Jones, Michael K. [Veterans Affairs Long Beach Healthcare System, Long Beach, CA (United States); Department of Medicine, University of California, Irvine, CA (United States); Szabo, Sandor [Veterans Affairs Long Beach Healthcare System, Long Beach, CA (United States); Department of Pathology, University of California, Irvine, CA (United States); Tarnawski, Andrzej S., E-mail: amrita.ahluwalia@va.gov [Veterans Affairs Long Beach Healthcare System, Long Beach, CA (United States); Department of Medicine, University of California, Irvine, CA (United States)

    2013-08-09

    Highlights: •Malignant colonic epithelial cells express VEGF and its receptors. •Cultured colon cancer cells secrete VEGF into the medium. •Inhibition of VEGF receptor significantly decreases colon cancer cell proliferation. •VEGF is critical for colon cancer cell growth. -- Abstract: Vascular endothelial growth factor A (referred to as VEGF) is implicated in colon cancer growth. Currently, the main accepted mechanism by which VEGF promotes colon cancer growth is via the stimulation of angiogenesis, which was originally postulated by late Judah Folkman. However, the cellular source of VEGF in colon cancer tissue; and, the expression of VEGF and its receptors VEGF-R1 and VEGF-R2 in colon cancer cells are not fully known and are subjects of controversy. Material and methods: We examined and quantified expression of VEGF, VEGF-R1 and VEGF-R2 in three different human colonic tissue arrays containing sections of adenocarcinoma (n = 43) and normal mucosa (n = 41). In human colon cancer cell lines HCT116 and HT29 and normal colon cell lines NCM356 and NCM460, we examined expression of VEGF, VEGF-R1 and VEGF-R2 mRNA and protein, VEGF production and secretion into the culture medium; and, the effect of a potent, selective inhibitor of VEGF receptors, AL-993, on cell proliferation. Results: Human colorectal cancer specimens had strong expression of VEGF in cancer cells and also expressed VEGF-R1 and VEGF-R2.In vitro studies showed that human colon cancer cell lines, HCT116 and HT29, but not normal colonic cell lines, express VEGF, VEGF-R1 and VEGF-R2 and secrete VEGF into the medium up to a concentration 2000 pg/ml within 48 h. Furthermore, we showed that inhibition of VEGF receptors using a specific VEGF-R inhibitor significantly reduced proliferation (by >50%) of cultured colon cancer cell lines. Conclusions: Our findings support the contention that VEGF generated by colon cancer cells stimulates their growth directly through an autocrine mechanism that is

  4. Erythropoietin in traumatic brain injury: study protocol for a randomised controlled trial.

    LENUS (Irish Health Repository)

    Nichol, Alistair

    2015-02-08

    Traumatic brain injury is a leading cause of death and disability worldwide. Laboratory and clinical studies demonstrate a possible beneficial effect of erythropoietin in improving outcomes in the traumatic brain injury cohort. However, there are concerns regarding the association of erythropoietin and thrombosis in the critically ill. A large-scale, multi-centre, blinded, parallel-group, placebo-controlled, randomised trial is currently underway to address this hypothesis.

  5. The effect of erythropoietin on cognition in affective disorders

    DEFF Research Database (Denmark)

    Ott, Caroline Vintergaard; Vinberg, Maj; Kessing, Lars V

    2016-01-01

    This is a secondary data analysis from our erythropoietin (EPO) trials. We examine (I) whether EPO improves speed of complex cognitive processing across bipolar and unipolar disorder, (II) if objective and subjective baseline cognitive impairment increases patients׳ chances of treatment......-efficacy and (III) if cognitive improvement correlates with better subjective cognitive function, quality of life and socio-occupational capacity. Patients with unipolar or bipolar disorder were randomized to eight weekly EPO (N=40) or saline (N=39) infusions. Cognition, mood, quality of life and socio......-occupational capacity were assessed at baseline (week 1), after treatment completion (week 9) and at follow-up (week 14). We used repeated measures analysis of covariance to investigate the effect of EPO on speed of complex cognitive processing. With logistic regression, we examined whether baseline cognitive...

  6. Neuroprotective effects of erythropoietin in patients with carbon monoxide poisoning.

    Science.gov (United States)

    Pang, Li; Bian, Miao; Zang, Xiu-Xian; Wu, Yang; Xu, Da-Hai; Dong, Ning; Wang, Zhi-Hao; Yan, Bai-Ling; Wang, Da-Wei; Zhao, Hui-Jie; Zhang, Nan

    2013-05-01

    The purpose of this study was to evaluate the efficacy of erythropoietin (EPO) for treating patients with carbon monoxide (CO) poisoning. We conducted a randomized, prospective study of 103 patients with CO poisoning in two groups: an EPO group (n = 54; patients received EPO) and a placebo group (n = 49; patients received normal saline). The study endpoints were the functional outcome at day 30 (the Barthel index and neurologic sequelae), National Institutes of Health Stroke Scale (NIHSS) score, and the levels of S-100β. At 18 days, the NIHSS score improved significantly and S-100β levels significantly decreased in patients in the EPO group. At 30 days, patients in the EPO group had a superior Barthel index and fewer patients had delayed neurologic sequelae (DNS). This study demonstrated that early administration of EPO to patients with CO poisoning improved neurological outcomes and reduced the incidence of DNS. © 2013 Wiley Periodicals, Inc.

  7. Erythropoietin Action in Stress Response, Tissue Maintenance and Metabolism

    Directory of Open Access Journals (Sweden)

    Yuanyuan Zhang

    2014-06-01

    Full Text Available Erythropoietin (EPO regulation of red blood cell production and its induction at reduced oxygen tension provides for the important erythropoietic response to ischemic stress. The cloning and production of recombinant human EPO has led to its clinical use in patients with anemia for two and half decades and has facilitated studies of EPO action. Reports of animal and cell models of ischemic stress in vitro and injury suggest potential EPO benefit beyond red blood cell production including vascular endothelial response to increase nitric oxide production, which facilitates oxygen delivery to brain, heart and other non-hematopoietic tissues. This review discusses these and other reports of EPO action beyond red blood cell production, including EPO response affecting metabolism and obesity in animal models. Observations of EPO activity in cell and animal model systems, including mice with tissue specific deletion of EPO receptor (EpoR, suggest the potential for EPO response in metabolism and disease.

  8. The Antioxidant Effect of Erythropoietin on Thalassemic Blood Cells

    Directory of Open Access Journals (Sweden)

    Johnny Amer

    2010-01-01

    Full Text Available Because of its stimulating effect on RBC production, erythropoietin (Epo is used to treat anemia, for example, in patients on dialysis or on chemotherapy. In β-thalassemia, where Epo levels are low relative to the degree of anemia, Epo treatment improves the anemia state. Since RBC and platelets of these patients are under oxidative stress, which may be involved in anemia and thromboembolic complications, we investigated Epo as an antioxidant. Using flow-cytometry technology, we found that in vitro treatment with Epo of blood cells from these patients increased their glutathione content and reduced their reactive oxygen species, membrane lipid peroxides, and external phosphatidylserine. This resulted in reduced susceptibility of RBC to undergo hemolysis and phagocytosis. Injection of Epo into heterozygous (Hbbth3/+ β-thalassemic mice reduced the oxidative markers within 3 hours. Our results suggest that, in addition to stimulating RBC and fetal hemoglobin production, Epo might alleviate symptoms of hemolytic anemias as an antioxidant.

  9. Erythropoietin enhances hippocampal response during memory retrieval in humans

    DEFF Research Database (Denmark)

    Miskowiak, Kamilla; O'Sullivan, Ursula; Harmer, Catherine J

    2007-01-01

    Although erythropoietin (Epo) is best known for its effects on erythropoiesis, recent evidence suggests that it also has neurotrophic and neuroprotective properties in animal models of hippocampal function. Such an action in humans would make it an intriguing novel compound for the treatment......) or saline in a between-subjects, double-blind, randomized design. Neural response during picture encoding and retrieval was tested 1 week later. Epo increased hippocampus response during picture retrieval (n = 11) compared with placebo (n = 12; p = 0.04) independent of changes in hematocrit....... This is consistent with upregulation of hippocampal BDNF and neurotrophic actions found in animals and highlights Epo as a promising candidate for treatment of psychiatric disorders....

  10. Erythropoietin treatment enhances muscle mitochondrial capacity in humans

    DEFF Research Database (Denmark)

    Plenge, Ulla; Belhage, Bo; Guadalupe-Grau, Amelia

    2012-01-01

    Erythropoietin (Epo) treatment has been shown to induce mitochondrial biogenesis in cardiac muscle along with enhanced mitochondrial capacity in mice. We hypothesized that recombinant human Epo (rhEpo) treatment enhances skeletal muscle mitochondrial oxidative phosphorylation (OXPHOS) capacity...... in humans. In six healthy volunteers rhEpo was administered by sub-cutaneous injection over 8 weeks with oral iron (100 mg) supplementation taken daily. Mitochondrial OXPHOS was quantified by high-resolution respirometry in saponin-permeabilized muscle fibers obtained from biopsies of the vastus lateralis....... rhEpo treatment increased OXPHOS (from 92 ± 5 to 113 ± 7 pmol·s(-1)·mg(-1)) and ETS (107 ± 4 to 143 ± 14 pmol·s(-1)·mg(-1), p muscle....

  11. Effects of recombinant humant erythropoietin in normal humans

    DEFF Research Database (Denmark)

    Lundby, Carsten; Olsen, Niels Vidiendal

    2011-01-01

    This review describes some of the physiological effects of recombinant human erythropoietin (EPO) in healthy humans. At the blood level EPO increases the arterial O2 content not only by increasing red blood cell volume, but also by an equally important decrease in plasma volume. Well before that...... result in suppression of endogenous EPO production through a decrease in intrarenal oxygen consumption. EPO elevates the arterial blood pressure even in healthy subjects. The receptor for EPO is present in many tissues. However, the functional effects of EPO in the skeletal muscle seem limited......, and although it has been speculated that non-erythropoietic effects of EPO (angiogenesis, shift in muscle fibre types, cognitive effects) may be responsible for the increase in exercise performance, this has not been confirmed. EPO induced haemodynamic effects call for careful monitoring during...

  12. Elevated serum and tissue VEGF associated with poor outcome in ...

    African Journals Online (AJOL)

    Enas Mohamed Ali

    Abstract Vascular endothelial growth factor (VEGF) has a potent angiogenesis functions in experimental models, although their role in the progression of human breast cancer is unclear. The aim of the current study was to examine the expression pattern of VEGF in serum and tissues of breast cancer patients, examine the ...

  13. Increased vascular endothelial growth factor (VEGF) expression in ...

    African Journals Online (AJOL)

    Vascular endothelial growth factor (VEGF), a well known angiogenic factor, has been shown to have direct and/or indirect influence on spinal cord injury (SCI). The purpose of this study is to observe VEGF expression changes in rats with SCI by bone marrow stromal cells (BMSCs) treatment. The mRNA expression of VEGF ...

  14. VEGF, the underlying factor for metabolic syndrome; fact or fiction?

    Science.gov (United States)

    Mazidi, Mohsen; Rezaie, Peyman; Kengne, A P; Stathopoulou, Maria G; Azimi-Nezhad, Mohsen; Siest, Sophie

    2017-11-01

    Metabolic syndrome (MetS) is currently diagnosed by the co-presence of at least three of the five following abnormalities: abdominal obesity, dysglycaemia, elevated serum triglycerides, low high-density cholesterol (HDL) and finally elevated blood pressure. Metabolic syndrome increases the risk of developing cardiovascular disease and diabetes. This review is on the associations between MetS and vascular endothelial growth factor (VEGF). VEGF induces migration and proliferation of endothelial cells (ECs), increases vascular permeability and has a role in tumor growth, adipose tissue expansion, age-related macular degeneration and diabetic retinopathy. Circulating levels of VEGFs are elevated in obese individuals and it has also been suggested that VEGF is secreted from adipose tissues, especially from intra-abdominal adipose tissue. There is abundant evidence to support that poor glycemic control in diabetic patients is associated with increased plasma VEGF, which in turn may cause hypertension and several vascular complications in diabetic patients. Circulating VEGF levels are increased in children and young adults with type 1 diabetes mellitus and middle-aged diabetic patients with proliferative retinopathy. It has been revealed that plasma VEGF increases in patients with hyperlipidemia and may trigger the development of atherosclerosis. It can be concluded that there is a positive association between VEGF and components of MetS. Because of the importance of this relationship, more investigations are needed in this field. Copyright © 2016. Published by Elsevier Ltd.

  15. Recombinant erythropoietin and analogues: a challenge for doping control.

    Science.gov (United States)

    Pascual, J A; Belalcazar, V; de Bolos, C; Gutiérrez, R; Llop, E; Segura, J

    2004-04-01

    Erythropoietin (EPO) increases the number of circulating erythrocytes and thus muscle oxygenation. The availability of the recombinant protein (rEPO) has increased the risk of its illegal use in sports, its detection being a difficult challenge. Five different hematopoietic parameters were initially chosen as indirect markers of rEPO abuse: concentration of serum EPO, concentration of serum-soluble transferrin receptors (sTFr), hematocrit, percentage of reticulocytes, and percentage of macrocytes. New models considering only hemoglobin, serum EPO concentration, and percentage of reticulocytes are simpler and seem to be more sensitive when low doses of rEPO are used. A more direct method of urine analysis (isoelectrofocusing, double blotting, and chemiluminescent detection) based on the charge differences between rEPO and endogenous EPO, related to their carbohydrate composition, provides proof of rEPO use. Furthermore, this approach permits the detection of darbepoetin, a direct analogue of EPO also known as NESP ("new erythropoiesis stimulating protein"). Recently a protein conjugate, "synthetic erythropoiesis protein" (SEP), containing precision-length, monodisperse, negatively charged polymers instead of oligosaccharides has been synthesized. Finally, EPO-mimetics are molecules capable of acting as EPO in dimerizing the EPO receptor. Two kinds of EPO-mimetics have been described: peptides and nonpeptides. The enhancement of oxygen availability to muscles by rEPO, analogues, and mimetics constitutes one of the main challenges to doping control. Major steps have already been developed for detection ofrEPO and some analogues. In the near future, the transfection to an athlete's body of genes that code for erythropoietin might be an emerging doping issue, and sports authorities have incorporated "gene doping" among the prohibited practices.

  16. Hepcidin clearance is associated with erythropoietin requirement in stable hemodialysis patients
.

    Science.gov (United States)

    Ashby, Damien; Busbridge, Mark; Hildebrand, Sarah; Clarke, Candice; Aldous, Georgina; Palan, Mitul; Murphy, Kevin; Duncan, Neill; Choi, Peter

    2017-05-01

    The discovery of hepcidin, the hormone regulating iron absorption and transport, has improved the understanding of anemia and erythropoietin treatment. Excessive hepcidin signaling causes anemia in chronic inflammatory conditions by restricting iron delivery to the bone marrow. Hepcidin is normally eliminated in the urine, and the high levels seen in renal failure are thought to contribute to renal anemia and resistance to erythropoietin. Clearance of hepcidin by hemodialysis was investigated in this study by measurement of plasma hepcidin before and after a single dialysis session in 204 patients. Results: Dialysis significantly reduced circulating hepcidin (p < 0.001) with median (IQR) clearance 47.7 (34.2 - 61.0)%. Dialytic hepcidin clearance was correlated with spKt/V (R = 0.202, p = 0.006), but not related to session length or membrane flux. There was also a strong correlation between hepcidin clearance and erythropoietin dose (R = -0.193, p = 0.007), sufficient to displace more traditional markers of erythropoietin resistance in a linear regression model, suggesting that increased dialytic removal of hepcidin could improve erythropoietin sensitivity. Hemodialysis reduces circulating hepcidin. Greater hepcidin clearance, which is related to spKt/V, is strongly associated with reduced erythropoietin requirement. This further implicates hepcidin in the pathogenesis of renal anemia and suggests that hepcidin could be a useful therapeutic target for dialysis patients.
.

  17. Changing paradigms of anti-VEGF in the Indian scenario

    Directory of Open Access Journals (Sweden)

    P Mahesh Shanmugam

    2014-01-01

    Full Text Available Anti-vascular endothelial growth factors (VEGF agents have revolutionized the treatment of retinal diseases. Use of anti-VEGF agents in the Indian Scenario present some unique challenges considering the absence of compounding pharmacies, poor penetrance of health insurance and limited affordability of the citizens of a developing economy. To study the changing paradigms of anti-VEGF use in the Indian scenario, all articles published by Indian authors, data from web-based surveys amongst Indian vitreo-retinal specialists were reviewed. In the paucity of compounding pharmacies in India, fractionation and injection techniques differ from those of developed countries. Frequent anti-VEGF monotherapy offers the best anatomical and visual results, but economics of scale do not allow the same in the Indian scenario, resulting in PRN dosing and combination of anti-VEGF with laser photocoagulation, being the commonly employed treatment protocols.

  18. [Role of VEGF in diseases of the retina].

    Science.gov (United States)

    Barquet, Luis Arias

    2015-03-01

    Angiogenesis is the process through which new blood vessels are formed, based on preexisting vessels, and is the paradigm of diseases such as cancer and exudative ageassociated macular degeneration (ARMD). Several proangiogenic factors have been identified, such as vascular endothelial growth factor (VEGF), especially VEGF-A, which activates endothelial cells and promotes cell proliferation, migration, and an increase in vascular permeability. VEGF is also involved in the etiopathogenesis of other retinal diseases, such as diabetic macular edema and macular edema secondary to retinal vein occlusion. Likewise, there is increasing evidence that placental growth factor (PIGF) acts recepsynergetically with VEGF in promoting these diseases. Currently, the main treatment for these diseases are the anti-VEGF drugs, aflibercept, ranibizumab and bevacizumab. These agents differ in their molecular structure and mechanism of action. Copyright © 2015 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  19. Differential expression of VEGF ligands and receptors in prostate cancer.

    Science.gov (United States)

    Woollard, David J; Opeskin, Kenneth; Coso, Sanja; Wu, Di; Baldwin, Megan E; Williams, Elizabeth D

    2013-05-01

    Prostate cancer disseminates to regional lymph nodes, however the molecular mechanisms responsible for lymph node metastasis are poorly understood. The vascular endothelial growth factor (VEGF) ligand and receptor family have been implicated in the growth and spread of prostate cancer via activation of the blood vasculature and lymphatic systems. The purpose of this study was to comprehensively examine the expression pattern of VEGF ligands and receptors in the glandular epithelium, stroma, lymphatic vasculature and blood vessels in prostate cancer. The localization of VEGF-A, VEGF-C, VEGF-D, VEGF receptor (VEGFR)-1, VEGFR-2, and VEGFR-3 was examined in cancerous and adjacent benign prostate tissue from 52 subjects representing various grades of prostate cancer. Except for VEGFR-2, extensive staining was observed for all ligands and receptors in the prostate specimens. In epithelial cells, VEGF-A and VEGFR-1 expression was higher in tumor tissue compared to benign tissue. VEGF-D and VEGFR-3 expression was significantly higher in benign tissue compared to tumor in the stroma and the endothelium of lymphatic and blood vessels. In addition, the frequency of lymphatic vessels, but not blood vessels, was lower in tumor tissue compared with benign tissue. These results suggest that activation of VEGFR-1 by VEGF-A within the carcinoma, and activation of lymphatic endothelial cell VEGFR-3 by VEGF-D within the adjacent benign stroma may be important signaling mechanisms involved in the progression and subsequent metastatic spread of prostate cancer. Thus inhibition of these pathways may contribute to therapeutic strategies for the management of prostate cancer. Copyright © 2012 Wiley Periodicals, Inc.

  20. Effect of erythropoietin administration on proteins participating in iron homeostasis in Tmprss6-mutated mask mice.

    Science.gov (United States)

    Frýdlová, Jana; Rychtarčíková, Zuzana; Gurieva, Iuliia; Vokurka, Martin; Truksa, Jaroslav; Krijt, Jan

    2017-01-01

    Tmprss6-mutated mask mice display iron deficiency anemia and high expression of hepcidin. The aim of the study was to determine the effect of erythropoietin administration on proteins participating in the control of iron homeostasis in the liver and spleen in C57BL/6 and mask mice. Administration of erythropoietin for four days at 50 IU/mouse/day increased hemoglobin and hematocrit in C57BL/6 mice, no such increase was seen in mask mice. Erythropoietin administration decreased hepcidin expression in C57BL/6 mice, but not in mask mice. Erythropoietin treatment significantly increased the spleen size in both C57BL/6 and mask mice. Furthermore, erythropoietin administration increased splenic Fam132b, Fam132a and Tfr2 mRNA content. At the protein level, erythropoietin increased the amount of splenic erythroferrone and transferrin receptor 2 both in C57BL/6 and mask mice. Splenic ferroportin content was decreased in erythropoietin-treated mask mice in comparison with erythropoietin-treated C57BL/6 mice. In mask mice, the amount of liver hemojuvelin was decreased in comparison with C57BL/6 mice. The pattern of hemojuvelin cleavage was different between C57BL/6 and mask mice: In both groups, a main hemojuvelin band was detected at approximately 52 kDa; in C57BL/6 mice, a minor cleaved band was seen at 47 kDa. In mask mice, the 47 kDa band was absent, but additional minor bands were detected at approximately 45 kDa and 48 kDa. The results provide support for the interaction between TMPRSS6 and hemojuvelin in vivo; they also suggest that hemojuvelin could be cleaved by another as yet unknown protease in the absence of functional TMPRSS6. The lack of effect of erythropoietin on hepcidin expression in mask mice can not be explained by changes in erythroferrone synthesis, as splenic erythroferrone content increased after erythropoietin administration in both C57BL/6 and mask mice.

  1. Transplantation of erythropoietin gene-modified neural stem cells improves the repair of injured spinal cord

    Directory of Open Access Journals (Sweden)

    Min-fei Wu

    2015-01-01

    Full Text Available The protective effects of erythropoietin on spinal cord injury have not been well described. Here, the eukaryotic expression plasmid pcDNA3.1 human erythropoietin was transfected into rat neural stem cells cultured in vitro. A rat model of spinal cord injury was established using a free falling object. In the human erythropoietin-neural stem cells group, transfected neural stem cells were injected into the rat subarachnoid cavity, while the neural stem cells group was injected with non-transfected neural stem cells. Dulbecco′s modified Eagle′s medium/F12 medium was injected into the rats in the spinal cord injury group as a control. At 1-4 weeks post injury, the motor function in the rat lower limbs was best in the human erythropoietin-neural stem cells group, followed by the neural stem cells group, and lastly the spinal cord injury group. At 72 hours, compared with the spinal cord injury group, the apoptotic index and Caspase-3 gene and protein expressions were apparently decreased, and the bcl-2 gene and protein expressions were noticeably increased, in the tissues surrounding the injured region in the human erythropoietin-neural stem cells group. At 4 weeks, the cavities were clearly smaller and the motor and somatosensory evoked potential latencies were remarkably shorter in the human erythropoietin-neural stem cells group and neural stem cells group than those in the spinal cord injury group. These differences were particularly obvious in the human erythropoietin-neural stem cells group. More CM-Dil-positive cells and horseradish peroxidase-positive nerve fibers and larger amplitude motor and somatosensory evoked potentials were found in the human erythropoietin-neural stem cells group and neural stem cells group than in the spinal cord injury group. Again, these differences were particularly obvious in the human erythropoietin-neural stem cells group. These data indicate that transplantation of erythropoietin gene-modified neural stem

  2. Effect of erythropoietin administration on proteins participating in iron homeostasis in Tmprss6-mutated mask mice.

    Directory of Open Access Journals (Sweden)

    Jana Frýdlová

    Full Text Available Tmprss6-mutated mask mice display iron deficiency anemia and high expression of hepcidin. The aim of the study was to determine the effect of erythropoietin administration on proteins participating in the control of iron homeostasis in the liver and spleen in C57BL/6 and mask mice. Administration of erythropoietin for four days at 50 IU/mouse/day increased hemoglobin and hematocrit in C57BL/6 mice, no such increase was seen in mask mice. Erythropoietin administration decreased hepcidin expression in C57BL/6 mice, but not in mask mice. Erythropoietin treatment significantly increased the spleen size in both C57BL/6 and mask mice. Furthermore, erythropoietin administration increased splenic Fam132b, Fam132a and Tfr2 mRNA content. At the protein level, erythropoietin increased the amount of splenic erythroferrone and transferrin receptor 2 both in C57BL/6 and mask mice. Splenic ferroportin content was decreased in erythropoietin-treated mask mice in comparison with erythropoietin-treated C57BL/6 mice. In mask mice, the amount of liver hemojuvelin was decreased in comparison with C57BL/6 mice. The pattern of hemojuvelin cleavage was different between C57BL/6 and mask mice: In both groups, a main hemojuvelin band was detected at approximately 52 kDa; in C57BL/6 mice, a minor cleaved band was seen at 47 kDa. In mask mice, the 47 kDa band was absent, but additional minor bands were detected at approximately 45 kDa and 48 kDa. The results provide support for the interaction between TMPRSS6 and hemojuvelin in vivo; they also suggest that hemojuvelin could be cleaved by another as yet unknown protease in the absence of functional TMPRSS6. The lack of effect of erythropoietin on hepcidin expression in mask mice can not be explained by changes in erythroferrone synthesis, as splenic erythroferrone content increased after erythropoietin administration in both C57BL/6 and mask mice.

  3. Effect of erythropoietin administration on proteins participating in iron homeostasis in Tmprss6-mutated mask mice

    Science.gov (United States)

    Frýdlová, Jana; Rychtarčíková, Zuzana; Gurieva, Iuliia; Vokurka, Martin; Truksa, Jaroslav

    2017-01-01

    Tmprss6-mutated mask mice display iron deficiency anemia and high expression of hepcidin. The aim of the study was to determine the effect of erythropoietin administration on proteins participating in the control of iron homeostasis in the liver and spleen in C57BL/6 and mask mice. Administration of erythropoietin for four days at 50 IU/mouse/day increased hemoglobin and hematocrit in C57BL/6 mice, no such increase was seen in mask mice. Erythropoietin administration decreased hepcidin expression in C57BL/6 mice, but not in mask mice. Erythropoietin treatment significantly increased the spleen size in both C57BL/6 and mask mice. Furthermore, erythropoietin administration increased splenic Fam132b, Fam132a and Tfr2 mRNA content. At the protein level, erythropoietin increased the amount of splenic erythroferrone and transferrin receptor 2 both in C57BL/6 and mask mice. Splenic ferroportin content was decreased in erythropoietin-treated mask mice in comparison with erythropoietin-treated C57BL/6 mice. In mask mice, the amount of liver hemojuvelin was decreased in comparison with C57BL/6 mice. The pattern of hemojuvelin cleavage was different between C57BL/6 and mask mice: In both groups, a main hemojuvelin band was detected at approximately 52 kDa; in C57BL/6 mice, a minor cleaved band was seen at 47 kDa. In mask mice, the 47 kDa band was absent, but additional minor bands were detected at approximately 45 kDa and 48 kDa. The results provide support for the interaction between TMPRSS6 and hemojuvelin in vivo; they also suggest that hemojuvelin could be cleaved by another as yet unknown protease in the absence of functional TMPRSS6. The lack of effect of erythropoietin on hepcidin expression in mask mice can not be explained by changes in erythroferrone synthesis, as splenic erythroferrone content increased after erythropoietin administration in both C57BL/6 and mask mice. PMID:29073189

  4. Transplantation of erythropoietin gene-modified neural stem cells improves the repair of injured spinal cord.

    Science.gov (United States)

    Wu, Min-Fei; Zhang, Shu-Quan; Gu, Rui; Liu, Jia-Bei; Li, Ye; Zhu, Qing-San

    2015-09-01

    The protective effects of erythropoietin on spinal cord injury have not been well described. Here, the eukaryotic expression plasmid pcDNA3.1 human erythropoietin was transfected into rat neural stem cells cultured in vitro. A rat model of spinal cord injury was established using a free falling object. In the human erythropoietin-neural stem cells group, transfected neural stem cells were injected into the rat subarachnoid cavity, while the neural stem cells group was injected with non-transfected neural stem cells. Dulbecco's modified Eagle's medium/F12 medium was injected into the rats in the spinal cord injury group as a control. At 1-4 weeks post injury, the motor function in the rat lower limbs was best in the human erythropoietin-neural stem cells group, followed by the neural stem cells group, and lastly the spinal cord injury group. At 72 hours, compared with the spinal cord injury group, the apoptotic index and Caspase-3 gene and protein expressions were apparently decreased, and the bcl-2 gene and protein expressions were noticeably increased, in the tissues surrounding the injured region in the human erythropoietin-neural stem cells group. At 4 weeks, the cavities were clearly smaller and the motor and somatosensory evoked potential latencies were remarkably shorter in the human erythropoietin-neural stem cells group and neural stem cells group than those in the spinal cord injury group. These differences were particularly obvious in the human erythropoietin-neural stem cells group. More CM-Dil-positive cells and horseradish peroxidase-positive nerve fibers and larger amplitude motor and somatosensory evoked potentials were found in the human erythropoietin-neural stem cells group and neural stem cells group than in the spinal cord injury group. Again, these differences were particularly obvious in the human erythropoietin-neural stem cells group. These data indicate that transplantation of erythropoietin gene-modified neural stem cells into the

  5. Impact of Alendronate and VEGF- antisense combined treatment on highly VEGF-expressing A431 cells

    OpenAIRE

    Mongerard-Coulanges, Medge; Migianu-Griffoni, Evelyne; Lecouvey, Marc; Jolles, Béatrice

    2009-01-01

    Abstract Bisphosphonates, and more specially nitrogen- containing bisphosphonates, which are in current use for the treatment of bone diseases, demonstrate proapoptotic, antiproliferative, antiangiogenic and anti-invasive properties on tumor cells. The amino- bisphosphonate alendronate is considered as a potential anticancer drug. In the case of A431 cells, which express high levels of VEGF, it had a two-step effect. At 24h, the antitumor properties of alendronate were counterbalan...

  6. Correlation between the expression of vegf and survival in osteosarcoma.

    Science.gov (United States)

    Baptista, André Mathias; Camargo, André Ferrari De França; Filippi, Renée Zon; Oliveira, Cláudia Regina Gomes Cardim Mendes De; Azevedo Neto, Raymundo Soares De; Camargo, Olavo Pires De

    2014-01-01

    To present a series of 50 consecutive patients with non-metastatic extremity osteosarcoma, and attempt to correlate expression of the vascular endothelial growth factor (VEGF) protein in biopsy tissue to their prognosis regarding overall survival, disease-free survival and local recurrence. Fifty cases of non-metastatic osteosarcoma of the extremities treated between 1986 and 2006 at Instituto de Ortopedia e Traumatologia da Universidade de São Paulo, São Paulo, Brasil, were evaluated regarding expression of the VEGF protein. There were 19 females and 31 males. The mean age was 16 years old (range 5-28 years old) and the mean follow-up was 60.6 months (range 25-167 months). The variables studied were age, gender, anatomic location, type of surgery, surgical margins, tumor size, post chemotherapy necrosis, local recurrence, pulmonary metastasis and death. Thirty-six patients showed VEGF expression on 30% or less cells (low), and the remaining 14 cases had VEGF expression above 30% (high). Among the 36 patients with low VEGF expression, nine developed pulmonary metastasis and four died (11.1%). Among the 14 patients with high VEGF expression, six developed pulmonary metastasis and three died (21.4%). There was no statistically significant correlation between the expression of VEGF and any of the variables studied. Level of Evidence IV, Therapeutic Study.

  7. Erythropoietin to Reduce Mortality in Traumatic Brain Injury: A Post-hoc Dose-effect Analysis.

    Science.gov (United States)

    Gantner, Dashiell C; Bailey, Michael; Presneill, Jeffrey; French, Craig J; Nichol, Alistair; Little, Lorraine; Bellomo, Rinaldo

    2017-02-01

    We aimed to assess whether the dosing regimen of erythropoietin shows a relationship to mortality in critically ill patients with traumatic brain injury (TBI). Erythropoietin may decrease mortality in patients with TBI; however, the optimal dosing regimen remains uncertain. We conducted a post-hoc analysis of a multicenter, randomized trial of weekly erythropoietin versus placebo in patients with moderate and severe TBI admitted to intensive care. We assessed whether the cumulative dosage of erythropoietin was differentially associated with all-cause patient mortality evaluated at 6 months after injury. There was a nonlinear relationship between dose and mortality (P = 0.008) that remained after adjustment for site and severity of illness (P = 0.01). Six-month mortality was lower in randomized patients who received 1 [adjusted hazard ratio (HR) 0.58, 95% confidence interval (CI) 0.33-1.01; P = 0.06] or 2 doses of erythropoietin (HR 0.31, 95% CI 0.12-0.80; P = 0.02) compared with those who received no doses. No benefit was seen with 3 doses (HR 1.55, 95% CI 0.66-3.62; P = 0.33). There was no differential effect of dose on functional neurological outcomes. Results across subgroups and secondary intention to treat analyses were consistent with primary findings. This post-hoc, hypothesis-generating analysis found potential reductions in mortality following 1 or 2 weekly doses of 40,000 IU of erythropoietin in intensive care unit patients with moderate or severe TBI, but not with 3 doses. These findings will inform the design of future trials of erythropoietin in critically ill patients with TBI and trauma.

  8. Non-hematopoietic effects of endogenous erythropoietin on lean mass and body weight regulation.

    Science.gov (United States)

    Reinhardt, Martin; Dey, Soumyadeep; Tom Noguchi, Constance; Zhang, Yuanyuan; Krakoff, Jonathan; Thearle, Marie S

    2016-07-01

    To investigate the concurrent relationships between human plasma erythropoietin concentrations and energy expenditure (EE), body composition, plasma leptin concentrations, and associations with weight change. Plasma to measure erythropoietin and leptin; data for body composition; 24-h EE measured in a whole-room calorimeter; and 75 g oral glucose tolerance testing were available from 109 full-heritage Pima Indians (55% male) from a larger study designed to understand the causes of obesity. Seventy-nine subjects had data for weight at a later visit (mean follow-up = 4.3 ± 1.9 years) to calculate percent weight change per year. Erythropoietin, adjusted for covariates, correlated with 24-h EE (r = 0.26, P = 0.007), sleeping EE (r = 0.29, P = 0.003), fat-free mass (r = 0.19, P = 0.05), and fat mass (r = 0.27, P = 0.005), but not insulin or glucose measures. The association of erythropoietin with 24-h EE was fully mediated by fat-free mass. Erythropoietin associated with leptin in women (ρ = 0.36, P = 0.01), but not in men (P = 0.9), independently from fat mass. The association of erythropoietin with percent weight change per year was in opposing directions (interaction: P = 0.002) in males (r = -0.35, P = 0.02) versus females (r = 0.37, P = 0.02). Non-hematopoietic endogenous erythropoietin action may be involved in body weight regulation in opposing directions in men and women, i.e., weight loss in men and weight gain in women. © 2016 The Obesity Society.

  9. No evidence for protective erythropoietin alpha signalling in rat hepatocytes

    Directory of Open Access Journals (Sweden)

    Frede Stilla

    2009-04-01

    Full Text Available Abstract Background Recombinant human erythropoietin alpha (rHu-EPO has been reported to protect the liver of rats and mice from ischemia-reperfusion injury. However, direct protective effects of rHu-EPO on hepatocytes and the responsible signalling pathways have not yet been described. The aim of the present work was to study the protective effect of rHu-EPO on warm hypoxia-reoxygenation and cold-induced injury to hepatocytes and the rHu-EPO-dependent signalling involved. Methods Loss of viability of isolated rat hepatocytes subjected to hypoxia/reoxygenation or incubated at 4°C followed by rewarming was determined from released lactate dehydrogenase activity in the absence and presence of rHu-EPO (0.2–100 U/ml. Apoptotic nuclear morphology was assessed by fluorescence microscopy using the nuclear fluorophores H33342 and propidium iodide. Erythropoietin receptor (EPOR, EPO and Bcl-2 mRNAs were quantified by real time PCR. Activation of JAK-2, STAT-3 and STAT-5 in hepatocytes and rat livers perfused in situ was assessed by Western blotting. Results In contrast to previous in vivo studies on ischemia-reperfusion injury to the liver, rHu-EPO was without any protective effect on hypoxic injury, hypoxia-reoxygenation injury and cold-induced apoptosis to isolated cultured rat hepatocytes. EPOR mRNA was identified in these cells but specific detection of the EPO receptor protein was not possible due to the lack of antibody specificity. Both, in the cultured rat hepatocytes (10 U/ml for 15 minutes and in the rat liver perfused in situ with rHu-EPO (8.9 U/ml for 15 minutes no evidence for EPO-dependent signalling was found as indicated by missing effects of rHu-EPO on phosphorylation of JAK-2, STAT-3 and STAT-5 and on the induction of Bcl-2 mRNA. Conclusion Together, these results indicate the absence of any protective EPO signalling in rat hepatocytes. This implies that the protection provided by rHu-EPO in vivo against ischemia-reperfusion and

  10. Synthesis of the human VEGF165 gene based on overlap PCR and ...

    African Journals Online (AJOL)

    Yomi

    2012-01-16

    Jan 16, 2012 ... human VEGF165 (hVEGF165) gene based on overlap PCR method and recombinant expressed in Chinese's hamster ovary (CHO) ... recombinant human VEGF165 (rhVEGF165) protein in CHO cells. Key words: Overlap .... Stable transfected positive clones appeared after 14 days when the. CHO cells not ...

  11. "Erythropoietin Utilization Evaluation And Two Brand Products Comparison, Eprex and Eposim "

    Directory of Open Access Journals (Sweden)

    H. Khalili

    2006-06-01

    Full Text Available Background and Aim: Anemia is one of the common problems in patients with chronic renal impairment. The most common cause of anemia in this patients is a decreased in erythropoietin hormone excretion, however other common cause include low life of red blood cells, loss of blood during dialysis, frequent blood sampling, uremia, iron, vitamin B12 and folic acid deficiency. Until introduction of erythropoietin in 1982, blood transfusion was an alternative for correction and maintaining hematocrit in normal range in dialyze patients. In current date, any dialyzed patient take rh-erythropoietin . Materials and Methods: The goal of this study is to evaluate erythropoietin utilization and comparing the effectiveness of the commercial product in the Iranian drugs market. The study was performed at nephrology and dialyze ward of Immam Khomeini hospital in a one year period. Results and Conclusion: Of the 30 patients' subject of study, 13 patients received eprex and 17 received epocim. Average dose of erythropoietin 2000IU was three times per week. The average plasma hemoglobin and hematocrit of patients prior to the treatment were 9.38 g/dl and 28% respectively. Increase in the hemoglobin and hematocrit in the group who received eprex was significantly higher than epocim group (p=0.001 and p=0.026 respectively. The incidents of side effects including hypertension, headache, pain at injection site, and influenza-like in eposim group were considerably higher than eprex.

  12. Erythropoietin and vascular endothelial growth factor as risk markers for severe hypoglycaemia in type 1 diabetes

    DEFF Research Database (Denmark)

    Kristensen, P L; Pedersen-Bjergaard, U; Schalkwijk, C

    2010-01-01

    . Plasma EPO and serum VEGF levels were measured at baseline with ELISA. Events of severe hypoglycaemia defined by third party assistance were recorded and validated in telephone interviews within 24 h. RESULTS: Totally 235 episodes of severe hypoglycaemia (1.1 episodes per patient-year) were reported...... by 82 patients (37%). At baseline, plasma EPO was 8.6 (3.1-34.3) U/l (median (range)), and serum VEGF was 52.2 (6.6-337) pg/ml. The levels of EPO and VEGF were not associated with frequency of severe and mild hypoglycaemia. The levels of EPO were not associated with age, sex, duration of diabetes, body...... mass index, HbAlc, C-peptide level or hypoglycaemia awareness status. The levels of VEGF were positively associated with age and female sex. CONCLUSIONS: Although several studies suggest that VEGF and EPO may affect brain function during hypoglycaemia, this study does not support random VEGF or EPO...

  13. Erythropoietin and interleukin-2 activate distinct JAK kinase family members.

    Science.gov (United States)

    Barber, D L; D'Andrea, A D

    1994-01-01

    The erythropoietin (EPO) receptor and the interleukin-2 (IL-2) receptor beta-chain subunit are members of the cytokine receptor superfamily. They have conserved primary amino acid sequences in their cytoplasmic domains and activate phosphorylation of common substrates, suggesting common biochemical signaling mechanisms. We have generated a cell line, CTLL-EPO-R, that contains functional cell surface receptors for both EPO and IL-2. CTLL-EPO-R cells demonstrated similar growth kinetics in EPO and IL-2. Stimulation with EPO resulted in the rapid, dose-dependent tyrosine phosphorylation of JAK2. In contrast, stimulation with IL-2 or the related cytokine IL-4 resulted in the rapid, dose-dependent tyrosine phosphorylation of JAK1 and an additional 116-kDa protein. This 116-kDa protein was itself immunoreactive with a polyclonal antiserum raised against JAK2 and appears to be a novel member of the JAK kinase family. Immune complex kinase assays confirmed that IL-2 and IL-4 activated JAK1 and EPO activated JAK2. These results demonstrate that multiple biochemical pathways are capable of conferring a mitogenic signal in CTLL-EPO-R cells and that the EPO and IL-2 receptors interact with distinct JAK kinase family members within the same cellular background. Images PMID:7935373

  14. Radioimmunoassay of erythropoietin in chronic uraemia or anephric patients

    Energy Technology Data Exchange (ETDEWEB)

    Naets, J.P.; Waks, D.; Garcia, J.F.; Tousaaint, C.; Buset, M.

    1986-01-01

    The erythropoietin (Ep) plasma titre of 41 anaemic patients with normal renal function or with renal insufficiency (with or without kidney) was measured by RIA and compared to values observed with the polycythaemic mouse assay. A good correlation was found with both methods (r = 0.88). However, about 20% of samples gave higher values with the bioassay. 21 Ep titres measurable by the bioassay ranged from 40 to 4400 mU (mean 717.1 mU) compared to 14.8 to 3788 mU (mean 484.7 mU) measured by the RIA. Low levels of Ep plasma titre have been observed in patients with renal insufficiency and no difference was found between nephric uraemic patients and the anephric group. These results suggest that the increased blood requirements in anephrics are not due to a smaller production of Ep, but ultimately to the presence of an inhibitor of erythropoiesis. The well-known inverse relationship between haematocrit and Ep level was not found in renal insufficiency. However, some humoral regulation of erythropoiesis seems to persist in these patients since the elevation of red blood cells by transfusions was followed by a decrease of the Ep level.

  15. Erythropoietin reduces the expression of myostatin in mdx dystrophic mice

    Energy Technology Data Exchange (ETDEWEB)

    Feder, D.; Rugollini, M.; Santomauro, A. Jr; Oliveira, L.P.; Lioi, V.P. [Faculdade de Medicina do ABC, Santo André, SP (Brazil); Santos, R. dos; Ferreira, L.G.; Nunes, M.T.; Carvalho, M.H. [Universidade de São Paulo, Instituto de Ciências Biomédicas, São Paulo, SP (Brazil); Delgado, P.O.; Carvalho, A.A.S. [Faculdade de Medicina do ABC, Santo André, SP (Brazil); Fonseca, F.L.A. [Faculdade de Medicina do ABC, Santo André, SP (Brazil); Universidade Federal de São Paulo, Ambientais e Farmacêuticas, Instituto de Ciências Químicas, Diadema, SP (Brazil)

    2014-09-05

    Erythropoietin (EPO) has been well characterized as a renal glycoprotein hormone regulating red blood cell production by inhibiting apoptosis of erythrocyte progenitors in hematopoietic tissues. EPO exerts regulatory effects in cardiac and skeletal muscles. Duchenne muscular dystrophy is a lethal degenerative disorder of skeletal and cardiac muscle. In this study, we tested the possible therapeutic beneficial effect of recombinant EPO (rhEPO) in dystrophic muscles in mdx mice. Total strength was measured using a force transducer coupled to a computer. Gene expression for myostatin, transforming growth factor-β1 (TGF-β1), and tumor necrosis factor-α (TNF-α) was determined by quantitative real time polymerase chain reaction. Myostatin expression was significantly decreased in quadriceps from mdx mice treated with rhEPO (rhEPO=0.60±0.11, control=1.07±0.11). On the other hand, rhEPO had no significant effect on the expression of TGF-β1 (rhEPO=0.95±0.14, control=1.05±0.16) and TNF-α (rhEPO=0.73±0.20, control=1.01±0.09). These results may help to clarify some of the direct actions of EPO on skeletal muscle.

  16. Erythropoietin elevation in the chronically hyperglycemic fetal lamb

    Energy Technology Data Exchange (ETDEWEB)

    Philipps, A.F. (Univ. of Connecticut Health Center, Farmington) Widness, J.A.; Garcia, J.F.; Raye, J.R.; Swartz, R.

    1982-05-01

    The effects of chronic fetal glucose infusion upon fetal oxygenation and endogenous erythropoietin (Ep) production were studied using the chronically catheterized fetal lamb. Fetal glucose infusion at rates between 5 and 20 mg/kg/min resulted in sustained fetal hyperglycemia. During glucose infusion (maximal glucose concentration achieved = 55.4 +/- 3.7 mg/dl) fetal arterial oxygen contents fell from 5.8 +/- 0.9 to 4.2 +/- 1.0 ml/dl while no changes were observed in simultaneously sampled, noninfused twins. Although plasma insulin concentration rose in the infused fetuses, the elevations were inconstant and no relationship between fetal plasma insulin concentration and decrement in fetal oxygen content was evident. The changes in plasma Ep concentration were noted prior to any significant fetal metabolic acidosis (as evidence of tissue hypoxia) and no changes in plasma Ep concentration were observed in simultaneously sampled noninfused twins. No relationship was apparent between fetal arterial plasma insulin and Ep concentrations. Since neither fetal anemia nor hemodilution occurred in these preparations, glucose-induced fetal hyposemia is the likely mechanism behind elevated fetal Ep concentrations in these experiments. Similarities between this animal model and human fetuses and infants of diabetic mothers suggest that chronic in utero hypoxemia may be a common feature responsible for such diverse abnomalities as polycythemia, hyperbilirubinemia, and late fetal demise. The mechanism behind the glucose-induced fetal hypoxemia is not known.

  17. Does Erythropoietin Regulate TRPC Channels in Red Blood Cells?

    Directory of Open Access Journals (Sweden)

    Jens Danielczok

    2017-03-01

    Full Text Available Background: Cation channels play an essential role in red blood cells (RBCs ion homeostasis. One set of ion channels are the transient receptor potential channels of canonical type (TRPC channels. The abundance of these channels in primary erythroblasts, erythroid cell lines and RBCs was associated with an increase in intracellular Ca2+ upon stimulation with Erythropoietin (Epo. In contrast two independent studies on Epo-treated patients revealed diminished basal Ca2+ concentration or reduced phosphatidylserine exposure to the outer membrane leaflet. Methods: To resolve the seemingly conflicting reports we challenged mature human and mouse RBCs of several genotypes with Epo and Prostaglandin E2 (PGE2 and recorded the intracellular Ca2+ content. Next Generation Sequencing was utilised to approach a molecular analysis of reticulocytes. Results/Conclusions: Our results allow concluding that Epo and PGE2 regulation of the Ca2+ homeostasis is distinctly different between murine and human RBCs and that changes in intracellular Ca2+ upon Epo treatment is a primary rather than a compensatory effect. In human RBCs, Epo itself has no effect on Ca2+ fluxes but inhibits the PGE2-induced Ca2+ entry. In murine mature RBCs functional evidence indicates TRPC4/C5 mediated Ca2+ entry activated by Epo whereas PGE2 leads to a TRPC independent Ca2+ entry.

  18. Therapeutic lymphangiogenesis using stem cell and VEGF-C hydrogel.

    Science.gov (United States)

    Hwang, Ji Hye; Kim, In Gul; Lee, Ji Young; Piao, Shuyu; Lee, David S; Lee, Tae Seung; Ra, Jeong Chan; Lee, Ji Youl

    2011-07-01

    Lymphedema is a manifestation of lymphatic system insufficiency. It arises from primary lymphatic dysplasia or secondary obliteration after lymph node dissection or irradiation. Although improvement of swelling can be achieved by comprehensive non-operative therapy, treatment of this condition requires lifelong care and good compliance. Recently molecular-based treatments using VEGF-C have been investigated by several researchers. We designed the present study to determine whether the therapeutic efficacy of implanted human adipose-derived stem cells (hADSCs) could be improved by applying a gelatin hydrogel containing VEGF-C (VEGF-C hydrogel) to the site of tissue injury in a lymphedema mouse model. Four weeks after the operation, we evaluated edema and determined lymphatic vessel density at various post-operative time points. Mice treated with hADSCs and VEGF-C hydrogel showed a significantly decreased dermal edema depth compared to the groups of mice that received hADSCs only or VEGF-C hydrogel only. Immunohistochemical analysis also revealed that the hADSC/VEGF-C hydrogel group showed significantly greater lymphatic vessel regeneration than all the other groups. hADSCs were detected in the implantation sites of all mice in the hADSC/VEGF-C group, and exhibited a lymphatic endothelial differentiation phenotype as determined by co-staining PKH-labeled hADSCs for the lymphatic marker LYVE-1. Our results suggest that co-administration of hADSCs and VEGF-C hydrogel has a substantial positive effect on lymphangiogenesis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Thrombospondin-1 and VEGF in inflammatory bowel disease

    Directory of Open Access Journals (Sweden)

    Canan Alkim

    2012-01-01

    Full Text Available Angiogenesis is an important process in the pathogenesis of chronic inflammation. We aimed to study the angiogeneic balance in inflammatory bowel disease (IBD by evaluating the expression of vascular endothelial growth factor (VEGF and thrombospondin-1 (TSP-1 on colonic epithelial cells, together with the expression of inducible nitric oxide synthase (iNOS.Twenty-one ulcerative colitis (UC, 14 Crohn's disease (CD, 11 colorectal cancer patients, and 11 healthy controls colonic biopsy samples were evaluated immunohistochemically.The expressions of TSP-1, VEGF, and iNOS in UC and CD groups were higher than expression in healthy control group, all with statistical significance. However, in colorectal cancer group, VEGF and iNOS expressions were increased importantly, but TSP-1 expression was not statistically different from healthy control group's expression. Both TSP-1 and VEGF expressions were correlated with iNOS expression distinctly but did not correlate with each other.Both pro-angiogeneic VEGF and antiangiogeneic TSP-1 expressions were found increased in our IBD groups, but in colorectal cancer group, only VEGF expression was increased. TSP-1 increases in IBD patients as a response to inflammatory condition, but this increase was not enough to suppress pathologic angiogenesis and inflammation in IBD.

  20. The anemia of microgravity and recumbency. Role of sympathetic neural control of erythropoietin production

    Science.gov (United States)

    Robertson, David; Krantz, Sanford B.; Biaggioni, Italo

    We hypothesize that reduced sympathetic stimulation of erythropoietin production may maintain the anemia which develops in virtually all space travellers. We tested this hypothesis in a human model of reduced sympathetic activity. Thirty-three patients with the Bradbury-Eggleston syndrome were divided into three groups according to their hemoglobin (Hgb) level. Patients with low Hgb had lower upright norepinephrine and lower upright renin. Patients with anemia also had inappropriately low plasma erythropoietin levels. We administered recombinant erythropoietin (Epogen) 25-50 units/kg s.c. 3 times per week and found that the anemia seen in autonomic failure could be reversed by this treatment. These results support the hypothesis that erythropoiesis is modulated by the sympathetic nervous system and that such mechanisms may also operate in the microgravity environment where sympathetic activity is reduced.

  1. Erythropoietin production by a hepatic adenoma in a patient with severe erythrocytosis.

    Science.gov (United States)

    Vik, Anders; Cui, Guanglin; Isaksen, Vidar; Wik, Trude; Hansen, John-Bjarne

    2009-01-01

    A 53-year-old woman with severe erythrocytosis (hemoglobin concentration 19.5 g/dl and hematocrit 0.59) was admitted to our hospital because of fatigue and headache. The serum erythropoietin (Epo) concentration was 68.6 U/l (reference range; 3.7-31.5). Further investigations excluded polycythemia vera or any lung or heart disease. Radiological examination showed a tumor in the left hepatic lobe. Needle biopsies were performed and the histopathological diagnosis was hepatocellular adenoma. Immunohistochemistry demonstrated erythropoietin expression in the adenomatous cells. Liver adenoma is a rare cause of erythrocytosis. For the first time, we report erythropoietin-positive immunoreactivity in liver adenomatous cells in a patient with erythrocytosis. (c) 2009 S. Karger AG, Basel.

  2. Testosterone Induces Erythrocytosis via Increased Erythropoietin and Suppressed Hepcidin: Evidence for a New Erythropoietin/Hemoglobin Set Point

    Science.gov (United States)

    Travison, Thomas G.; Basaria, Shehzad; Davda, Maithili N.; Guo, Wen; Li, Michelle; Connor Westfall, John; Bae, Harold; Gordeuk, Victor; Bhasin, Shalender

    2014-01-01

    Background. The mechanisms by which testosterone increases hemoglobin and hematocrit remain unclear. Methods. We assessed the hormonal and hematologic responses to testosterone administration in a clinical trial in which older men with mobility limitation were randomized to either placebo or testosterone gel daily for 6 months. Results. The 7%–10% increase in hemoglobin and hematocrit, respectively, with testosterone administration was associated with significantly increased erythropoietin (EPO) levels and decreased ferritin and hepcidin levels at 1 and 3 months. At 6 months, EPO and hepcidin levels returned toward baseline in spite of continued testosterone administration, but EPO levels remained nonsuppressed even though elevated hemoglobin and hematocrit higher than at baseline, suggesting a new set point. Consistent with increased iron utilization, soluble transferrin receptor (sTR) levels and ratio of sTR/log ferritin increased significantly in testosterone-treated men. Hormonal and hematologic responses were similar in anemic participants. The majority of testosterone-treated anemic participants increased their hemoglobin into normal range. Conclusions. Testosterone-induced increase in hemoglobin and hematocrit is associated with stimulation of EPO and reduced ferritin and hepcidin concentrations. We propose that testosterone stimulates erythropoiesis by stimulating EPO and recalibrating the set point of EPO in relation to hemoglobin and by increasing iron utilization for erythropoiesis. PMID:24158761

  3. Erythropoietin, ferritin, haptoglobin, hemoglobin and transferrin receptor in metabolic syndrome: a case control study

    Directory of Open Access Journals (Sweden)

    Hämäläinen Päivi

    2012-09-01

    Full Text Available Abstract Background Increased ferritin concentrations are associated with metabolic syndrome (MetS. The association between ferritin as well as hemoglobin level and individual MetS components is unclear. Erythropoietin levels in subjects with MetS have not been determined previously. The aim of this study was to compare serum erythropoietin, ferritin, haptoglobin, hemoglobin, and transferrin receptor (sTFR levels between subjects with and without MetS and subjects with individual MetS components. Methods A population based cross-sectional study of 766 Caucasian, middle-aged subjects (341 men and 425 women from five age groups born in Pieksämäki, Finland who were invited to a health check-up in 2004 with no exclusion criteria. Laboratory analyzes of blood samples collected in 2004 were done during year 2010. MetS was defined by National Cholesterol Education Program criteria. Results 159 (53% men and 170 (40% women of study population met MetS criteria. Hemoglobin and ferritin levels as well as erythropoietin and haptoglobin levels were higher in subjects with MetS (p  Conclusion Subjects with MetS have elevated hemoglobin, ferritin, erythropoietin and haptoglobin concentrations. Higher hemoglobin levels are related to all components of MetS. Higher ferritin levels associate with TG, abdominal obesity, elevated glucose or low high density cholesterol. Haptoglobin levels associate with blood pressure or elevated glucose. However, erythropoietin levels are related only with abdominal obesity. Higher serum erythropoietin concentrations may suggest underlying adipose tissue hypoxemia in MetS.

  4. CXCL7-Mediated Stimulation of Lymphangiogenic Factors VEGF-C, VEGF-D in Human Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Minghuan Yu

    2010-01-01

    Full Text Available Increased expression of lymphangiogenesis factors VEGF-C/D and heparanase has been correlated with the invasion of cancer. Furthermore, chemokines may modify matrix to facilitate metastasis, and they are associated with VEGF-C and heparanase. The chemokine CXCL7 binds heparin and the G-protein-linked receptor CXCR2. We investigated the effect of CXCR2 blockade on the expression of VEGF-C/D, heparanase, and on invasion. CXCL7 siRNA and a specific antagonist of CXCR2 (SB225002 were used to treat CXCL7 stably transfected MCF10AT cells. Matrigel invasion assays were performed. VEGF-C/D expression and secretion were determined by real-time PCR and ELISA assay, and heparanase activity was quantified by ELISA. SB225002 blocked VEGF-C/D expression and secretion (P<.01. CXCL7 siRNA knockdown decreased heparanase (P<.01. Both SB225002 and CXCL7 siRNA reduced the Matrigel invasion (P<.01. The MAP kinase signaling pathway was not involved. The CXCL7/CXCR2 axis is important for cell invasion and the expression of VEGF-C/D and heparanase, all linked to invasion.

  5. Erythropoietin treatment does not compromise cardiovascular function in chronic renal failure

    DEFF Research Database (Denmark)

    Haedersdal, C; Mehlsen, J; Stenver, Doris Irene

    1994-01-01

    The anemia in patients with chronic renal failure can be corrected through treatment with recombinant human erythropoietin treatment. This correction is associated with changes in the rheologic variables, which could explain the changes in hemodynamics found by many investigators. The authors have...... followed up 11 patients with chronic renal failure on hemodialysis before and during six months of therapy with erythropoietin. The measurements were made before treatment, after four months of therapy, and after six months of therapy. The measurements included hematocrit, osmotic resistance of the red...

  6. Erythropoietin for neuroprotection in neonatal encephalopathy: safety and pharmacokinetics.

    Science.gov (United States)

    Wu, Yvonne W; Bauer, Larry A; Ballard, Roberta A; Ferriero, Donna M; Glidden, David V; Mayock, Dennis E; Chang, Taeun; Durand, David J; Song, Dongli; Bonifacio, Sonia L; Gonzalez, Fernando F; Glass, Hannah C; Juul, Sandra E

    2012-10-01

    To determine the safety and pharmacokinetics of erythropoietin (Epo) given in conjunction with hypothermia for hypoxic-ischemic encephalopathy (HIE). We hypothesized that high dose Epo would produce plasma concentrations that are neuroprotective in animal studies (ie, maximum concentration = 6000-10000 U/L; area under the curve = 117000-140000 U*h/L). In this multicenter, open-label, dose-escalation, phase I study, we enrolled 24 newborns undergoing hypothermia for HIE. All patients had decreased consciousness and acidosis (pH score ≤ 5, or ongoing resuscitation at 10 minutes. Patients received 1 of 4 Epo doses intravenously: 250 (N = 3), 500 (N = 6), 1000 (N = 7), or 2500 U/kg per dose (N = 8). We gave up to 6 doses every 48 hours starting at <24 hours of age and performed pharmacokinetic and safety analyses. Patients received mean 4.8 ± 1.2 Epo doses. Although Epo followed nonlinear pharmacokinetics, excessive accumulation did not occur during multiple dosing. At 500, 1000, and 2500 U/kg Epo, half-life was 7.2, 15.0, and 18.7 hours; maximum concentration was 7046, 13780, and 33316 U/L, and total Epo exposure (area under the curve) was 50306, 131054, and 328002 U*h/L, respectively. Drug clearance at a given dose was slower than reported in uncooled preterm infants. No deaths or serious adverse effects were seen. Epo 1000 U/kg per dose intravenously given in conjunction with hypothermia is well tolerated and produces plasma concentrations that are neuroprotective in animals. A large efficacy trial is needed to determine whether Epo add-on therapy further improves outcome in infants undergoing hypothermia for HIE.

  7. Targeting VEGF-A with a vaccine decreases inflammation and joint destruction in experimental arthritis.

    Science.gov (United States)

    Semerano, Luca; Duvallet, Emilie; Belmellat, Nadia; Marival, Nicolas; Schall, Nicolas; Monteil, Maëlle; Grouard-Vogel, Géraldine; Bernier, Emilie; Lecouvey, Marc; Hlawaty, Hanna; Muller, Sylviane; Boissier, Marie-Christophe; Assier, Eric

    2016-01-01

    Inflammation and angiogenesis are two tightly linked processes in arthritis, and therapeutic targeting of pro-angiogenic factors may contribute to control joint inflammation and synovitis progression. In this work, we explored whether vaccination against vascular endothelial growth factor (VEGF) ameliorates collagen-induced arthritis (CIA). Anti-VEGF vaccines were heterocomplexes consisting of the entire VEGF cytokine (or a VEGF-derived peptide) linked to the carrier protein keyhole limpet hemocyanin (KLH). Two kinds of vaccines were separately tested in two independent experiments of CIA. In the first, we tested a kinoid of the murine cytokine VEGF (VEGF-K), obtained by conjugating VEGF-A to KLH. For the second, we selected two VEGF-A-derived peptide sequences to produce heterocomplexes (Vpep1-K and Vpep2-K). DBA/1 mice were immunized with either VEGF-K, Vpep1-K, or Vpep2-K, before CIA induction. Clinical and histological scores of arthritis, anti-VEGF, anti-Vpep Ab titers, and anti-VEGF Abs neutralizing capacity were determined. Both VEGF-K and Vpep1-K significantly ameliorated clinical arthritis scores and reduced synovial inflammation and joint destruction at histology. VEGF-K significantly reduced synovial vascularization. None of the vaccines reduced anti-collagen Ab response in mice. Both VEGF-K and Vpep1-K induced persistently high titers of anti-VEGF Abs capable of inhibiting VEGF-A bioactivity. Vaccination against the pro-angiogenic factor VEGF-A leads to the production of anti-VEGF polyclonal Abs and has a significant anti-inflammatory effect in CIA. Restraining Ab response to a single peptide sequence (Vpep1) with a peptide vaccine effectively protects immunized mice from joint inflammation and destruction.

  8. Current perspectives on protective roles of erythropoietin in cardiovascular system: erythropoietin receptor as a novel therapeutic target.

    Science.gov (United States)

    Kagaya, Yutaka; Asaumi, Yasuhide; Wang, Wanting; Takeda, Morihiko; Nakano, Makoto; Satoh, Kimio; Fukumoto, Yoshihiro; Shimokawa, Hiroaki

    2012-06-01

    Erythropoietin (EPO) is a principal regulator that promotes proliferation and terminal differentiation of erythroid progenitor cells. EPO receptors are expressed not only in hematopoietic lineage cells but also in the cardiovascular system. We performed animal experiments using transgene-rescued EPO receptor null mutant mice (EpoR-/- rescued) that express the EPO receptor exclusively in the hematopoietic cells. The results of these experiments suggest that endogenous EPO/EPO receptor system in the heart exerts cardioprotective effects against myocardial injury induced by ischemia followed by reperfusion and pressure-overload induced left ventricular dysfunction. Many animal experiments have shown that the administration of recombinant human EPO also elicits cardioprotective effects against myocardial injury induced by ischemia and reperfusion. In contrast to the promising results of these animal experiments, recent clinical trials failed to demonstrate the reduction in infarct size or improvement of cardiac function by the administration of recombinant human EPO in patients with acute myocardial infarction who underwent primary percutaneous coronary intervention. It should be tested in future clinical studies whether a relatively low dose of recombinant human EPO or its derivatives that have no erythropoietic action reduces infarct size and ameliorates cardiac dysfunction in patients with acute myocardial infarction. In this article, we review implications of anemia associated with chronic heart failure, roles of the endogenous EPO/EPO receptor system, and the effects of the administration of erythropoiesis-stimulating agents in pathologic conditions of the heart by focusing on the EPO receptor as a potential candidate of novel therapeutic targets in cardiovascular diseases.

  9. SREBP inhibits VEGF expression in human smooth muscle cells.

    Science.gov (United States)

    Motoyama, Koka; Fukumoto, Shinya; Koyama, Hidenori; Emoto, Masanori; Shimano, Hitoshi; Maemura, Koji; Nishizawa, Yoshiki

    2006-03-31

    Sterol regulatory element-binding proteins (SREBPs) are transcription factors that regulate expression of genes encoding enzymes for lipid biosynthesis. SREBPs are activated by HMG-CoA reductase inhibitors (statins). Statins have been also reported to suppress vascular endothelial growth factor (VEGF) expression in vascular smooth muscle cells (VSMCs). Therefore, we hypothesized that SREBPs are involved in statin-mediated regulation of VEGF production in VSMCs. SREBP1 was robustly expressed, and was activated by atorvastatin in VSMCs, as demonstrated by increased levels of the mature nuclear form of SREBP1, and increased promoter activities of a reporter containing sterol regulatory elements by atorvastatin. Moreover, overexpression of SREBP1a dose-dependently suppressed VEGF promoter activity. Site-specific mutation or deletion of the proximal Sp1 sites reduced the inhibitory effects of SREBP1a on VEGF promoter activity. These data demonstrated that SREBP1, activated by atorvastatin, suppressed VEGF expression through the indirect interaction with the proximal tandem Sp1 sites in VSMCs.

  10. Anti-VEGF Agents for Ocular Angiogenesis and Vascular Permeability

    Directory of Open Access Journals (Sweden)

    Kenichi Kimoto

    2012-01-01

    Full Text Available We review articles describing intravitreal injection of anti-VEGF drug trials, while discussing the mechanisms of the action of anti-VEGF antibodies, and also evaluating their outcomes. Intraocular injections of anti-VEGF drug are considered to be an effective treatment for macular edema after retinal vein occlusion, however, recurrent/persistent edema is common. The recent reports may lead to a shift in treatment paradigm for DME, from laser photocoagulation, to newer approaches using anti-VEGF drugs. There have been several well-publicized prospective, randomized studies that demonstrated the efficacy of intravitreal injection of anti-VEGF drugs for patients with AMD. Adjuvant bevacizumab for neovascular glaucoma may prevent further PAS formation, and it is likely to open up a therapeutic window for a panretinal photocoagulation and trabeculectomy. Intravitreal injection of bevacizumab (IVB results in a substantial decrease in bleeding from the retinal vessels or new vessels during a standard vitrectomy. IVB has also been reported to be effective for inducing the regression of new vessels in proliferative diabetic retinopathy. The use of bevacizumab in stage 4 or 5 retinopahty of permaturity (ROP is to reduce the plus sign to help reduce hemorrhage during the subsequent vitrectomy. Some authors reported cases of resolution of stage 4 A ROP after bevacizumab injection.

  11. Exercise induced capillary growth in human skeletal muscle and the dynamics of VEGF

    DEFF Research Database (Denmark)

    Høier, Birgitte; Hellsten, Ylva

    2014-01-01

    , these VEGF containing vesicles are redistributed towards the sarcolemma where the contents are secreted into the extracellular fluid. VEGF mRNA expression is increased primarily after exercise, which allows for a more rapid replenishment of VEGF stores lost through secretion during exercise. Future studies...... in the muscle interstitium, acts on VEGF receptors on the capillary endothelium and thereby stimulates angiogenic processes. A primary source of muscle interstitial VEGF during exercise is the skeletal muscle fibers which contain large stores of VEGF within vesicles. We propose that, during muscle activity...

  12. Investigation of Antiangiogenic Tumor Therapy Potential of Microencapsulated HEK293 VEGF165b Producing Cells

    Directory of Open Access Journals (Sweden)

    Fatemeh Afkhami

    2010-01-01

    encapsulated and non-encapsulated cells was similar. The effect of VEGF165b harvested from encapsulated cells on Human Umbilical Vein Endothelial cells (HUVECs proliferation were also examined.The same inhibitory effects on HUVECs proliferation was seen when the cells were incubated with a mixture of VEGF165b and a 2-fold VEGF165b or with VEGF165b and 2-fold excess VEGF165b released from encapsulated cells. Subcutaneous injection of microencapsulated VEGF165b producing cells in tumor site of nude mice resulted in the reduction of the number of vessels around the tumors.

  13. DNA methylation regulates expression of VEGF-C, and S-adenosylmethionine is effective for VEGF-C methylation and for inhibiting cancer growth

    Energy Technology Data Exchange (ETDEWEB)

    Da, M.X. [Department of Surgical Oncology, Gansu Provincial Hospital, Lanzhou (China); Zhang, Y.B. [Department of Surgery, Ningxia Medical University, Yinchuan (China); Yao, J.B. [Department of Surgical Oncology, Gansu Provincial Hospital, Lanzhou (China); Duan, Y.X. [Department of Surgery, Ningxia Medical University, Yinchuan (China)

    2014-09-30

    DNA hypomethylation may activate oncogene transcription, thus promoting carcinogenesis and tumor development. S-adenosylmethionine (SAM) is a methyl donor in numerous methylation reactions and acts as an inhibitor of intracellular demethylase activity, which results in hypermethylation of DNA. The main objectives of this study were to determine whether DNA hypomethylation correlated with vascular endothelial growth factor-C (VEGF-C) expression, and the effect of SAM on VEGF-C methylation and gastric cancer growth inhibition. VEGF-C expression was assayed by Western blotting and RT-qPCR in gastric cancer cells, and by immunohistochemistry in tumor xenografts. VEGF-C methylation was assayed by bisulfite DNA sequencing. The effect of SAM on cell apoptosis was assayed by flow cytometry analyses and its effect on cancer growth was assessed in nude mice. The VEGF-C promoters of MGC-803, BGC-823, and SGC-7901 gastric cancer cells, which normally express VEGF-C, were nearly unmethylated. After SAM treatment, the VEGF-C promoters in these cells were highly methylated and VEGF-C expression was downregulated. SAM also significantly inhibited tumor growth in vitro and in vivo. DNA methylation regulates expression of VEGF-C. SAM can effectively induce VEGF-C methylation, reduce the expression of VEGF-C, and inhibit tumor growth. SAM has potential as a drug therapy to silence oncogenes and block the progression of gastric cancer.

  14. Prediction of perinatal brain damage by cord plasma vasopressin, erythropoietin, and hypoxanthine values.

    Science.gov (United States)

    Ruth, V; Autti-Rämö, I; Granström, M L; Korkman, M; Raivio, K O

    1988-11-01

    For an assessment of whether cord plasma arginine vasopressin, erythropoietin, and hypoxanthine concentrations are predictors of perinatal brain damage, these concentrations were measured in 62 infants born after preeclampsia of pregnancy, 31 acutely asphyxiated infants, and 38 control infants. Follow-up at 2 years included neurologic examination and the determination of a Bayley mental score. Clear abnormality (death, cerebral palsy, or developmental delay) was found in four infants in the preeclampsia group and five in the asphyxia group; slight abnormality was found in 12 and 6 infants, respectively; and no abnormality was found in the remainder. Neither arginine vasopressin values nor hypoxanthine values predicted adverse outcome in either study group. A high erythropoietin level was found in infants born after preeclampsia regardless of outcome: normal outcome (geometric mean (GM), 102; 95% confidence interval [CI], 69 to 153 mU/ml), slightly abnormal outcome (GM, 100; 95% CI, 37 to 270 mU/ml) or clearly abnormal outcome (GM, 84; 95% CI, 19 to 378 mU/ml). However, asphyxiated infants with clearly abnormal outcome had higher erythropoietin values (GM, 67; 95% CI, 33 to 137 mU/ml; p less than 0.05) than the normal infants (GM, 37; 95% CI, 23 to 59 mU/ml). We conclude that a high erythropoietin level after normal pregnancy, but not after preeclampsia, indicates an increased risk for cerebral palsy or death.

  15. Glycoengineering of Chinese hamster ovary cells for enhanced erythropoietin N-glycan branching and sialylation

    DEFF Research Database (Denmark)

    Yin, Bojiao; Gao, Yuan; Chung, Cheng-yu

    2015-01-01

    -glycosylation of recombinant erythropoietin (rEPO), a human α2,6-sialyltransferase (ST6Gal1) was expressed in Chinese hamster ovary (CHO-K1) cells. Sialylation increased on both EPO and CHO cellular proteins as observed by SNA lectin analysis, and HPLC profiling revealed that the sialic acid content of total glycans on EPO...

  16. Chronic erythropoietin treatment improves diet-induced glucose intolerance in rats

    DEFF Research Database (Denmark)

    Caillaud, Corinne; Mechta, Mie; Ainge, Heidi

    2015-01-01

    Erythropoietin (EPO) ameliorates glucose metabolism through mechanisms not fully understood. In this study, we investigated the effect of EPO on glucose metabolism and insulin signaling in skeletal muscle. A 2-week EPO treatment of rats fed with a high-fat diet (HFD) improved fasting glucose leve...

  17. How bio-questionable are the different recombinant human erythropoietin copy products in Thailand?

    NARCIS (Netherlands)

    Halim, Liem Andhyk|info:eu-repo/dai/nl/412608294; Brinks, Vera|info:eu-repo/dai/nl/31395979X; Jiskoot, Wim; Romeijn, Stefan; Praditpornsilpa, Kearkiat; Assawamakin, Anunchai; Schellekens, Huub|info:eu-repo/dai/nl/068406762

    2014-01-01

    PURPOSE: The high prevalence of pure red cell aplasia in Thailand has been associated with the sharp increase in number of recombinant human erythropoietin (rhEPO) copy products, based on a classical generic regulatory pathway, which have entered the market. This study aims to assess the quality of

  18. New insights for identification of doping with recombinant human erythropoietin micro-doses after high hydration

    DEFF Research Database (Denmark)

    Martin, L.; Ashenden, M; Bejder, Jacob

    2016-01-01

    To minimize the chances of being caught after doping with recombinant human erythropoietins (rhEPO), athletes have turned to new practices using micro-doses and excess fluid ingestion to accelerate elimination and decrease the probability of detection. Our objective was to test the sensitivity of...

  19. The Significance of Erythropoietin Receptor (EpoR) Acquisition by Breast Cancer Cells

    Science.gov (United States)

    2007-08-01

    CONTRACTING ORGANIZATION: Beth Israel Deaconess Medical Center...ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER Beth Israel Deaconess Medical Center Boston, MA 02215 9. SPONSORING...Arcasoy MO, Kirkpatrick JP, Vujaskovic Z, Dewhirst MW, Blackwell KL. Erythropoietin inhibits apoptosis in breast cancer cells via an Akt-dependent

  20. Early intervention with erythropoietin does not affect the outcome of acute kidney injury (the EARLYARF trial).

    Science.gov (United States)

    Endre, Zoltán H; Walker, Robert J; Pickering, John W; Shaw, Geoffrey M; Frampton, Christopher M; Henderson, Seton J; Hutchison, Robyn; Mehrtens, Jan E; Robinson, Jillian M; Schollum, John B W; Westhuyzen, Justin; Celi, Leo A; McGinley, Robert J; Campbell, Isaac J; George, Peter M

    2010-06-01

    We performed a double-blind placebo-controlled trial to study whether early treatment with erythropoietin could prevent the development of acute kidney injury in patients in two general intensive care units. As a guide for choosing the patients for treatment we measured urinary levels of two biomarkers, the proximal tubular brush border enzymes gamma-glutamyl transpeptidase and alkaline phosphatase. Randomization to either placebo or two doses of erythropoietin was triggered by an increase in the biomarker concentration product to levels above 46.3, with a primary outcome of relative average plasma creatinine increase from baseline over 4 to 7 days. Of 529 patients, 162 were randomized within an average of 3.5 h of a positive sample. There was no difference in the incidence of erythropoietin-specific adverse events or in the primary outcome between the placebo and treatment groups. The triggering biomarker concentration product selected patients with more severe illness and at greater risk of acute kidney injury, dialysis, or death; however, the marker elevations were transient. Early intervention with high-dose erythropoietin was safe but did not alter the outcome. Although these two urine biomarkers facilitated our early intervention, their transient increase compromised effective triaging. Further, our study showed that a composite of these two biomarkers was insufficient for risk stratification in a patient population with a heterogeneous onset of injury.

  1. Disease Activity and Conversion into Multiple Sclerosis after Optic Neuritis Is Treated with Erythropoietin

    Directory of Open Access Journals (Sweden)

    Kurt-Wolfram Sühs

    2016-09-01

    Full Text Available Changes in cerebral lesion load by magnetic resonance imaging (MRI in patients from a double-blind, placebo-controlled, phase II study on erythropoietin in clinically isolated optic neuritis (ClinicalTrials.gov, NCT00355095 were analyzed. Therefore, patients with acute optic neuritis were assigned to receive either 33,000 IU of recombinant human erythropoietin (IV daily for three days, or a placebo, as an add-on to methylprednisolone. Of 35 patients, we investigated changes in cerebral lesion load in MRIs obtained at baseline and at weeks 4, 8, and 16. In 5 of the 35 patients, we found conversion into multiple sclerosis (MS based on MRI progression only. These five patients had received the placebo. Another five patients showed MRI progression together with relapses. Three of these patients had received erythropoietin, and two the placebo. Yet, analyzing the change in absolute numbers of periventricular, juxtacortical, and infratentorial lesions including gadolinium-enhancing lesions, there were no significant differences between the groups. Although effective in terms of retinal nerve fiber layer protection, erythropoietin treatment of acute isolated optic neuritis did not influence further evolution of MRI lesions in the brain when comparing absolute numbers. However, early conversion from clinically isolated syndrome to MS assessed by MRI activity seemed to occur more frequently in the placebo-treated group.

  2. Carbon monoxide in chronic uraemia related to erythropoietin treatment and smoking habits

    DEFF Research Database (Denmark)

    Thunedborg, P; Nielsen, A L; Brinkenfeldt, H

    1995-01-01

    In 69 patients on chronic haemodialysis, blood sampled randomly during dialysis was analyzed for carboxyhaemoglobin (COHb). The median value was 1.40% (range 0.9-2.3) in non-smoking patients and (1.4-7.5) in smokers. In non-smokers treated with erythropoietin (EPO) correlation was found between C...

  3. Protective effects of erythropoietin in cardiac ischemia - From bench to bedside

    NARCIS (Netherlands)

    Lipsic, Erik; Schoemaker, Regien G.; van der Meer, Peter; Voors, Adriaan A.; van Veldhuisen, Dirk J.; van Gilst, Wiek H.

    2006-01-01

    Erythropoietin (EPO) is a hypoxia-induced hormone produced in the kidneys that stimulates hematopoiesis in the bone marrow. However, recent studies have also shown important nonhematopoietic effects of EPO. A functional EPO receptor is found in the cardiovascular system, including endothelial cells

  4. Release of erythropoietin and neuron-specific enolase after breath holding in competing free divers

    DEFF Research Database (Denmark)

    Kjeld, Thomas; Jattu, T; Nielsen, Henrik

    2015-01-01

    Free diving is associated with extreme hypoxia. This study evaluated the combined effect of maximal static breath holding and underwater swimming on plasma biomarkers of tissue hypoxemia: erythropoietin, neuron-specific enolase and S100B, C-reactive protein, pro-atrial natriuretic peptide...

  5. Detection of erythropoietin misuse by the Athlete Biological Passport combined with reticulocyte percentage

    DEFF Research Database (Denmark)

    Bejder, Jacob; Aachmann-Andersen, Niels Jacob; Bonne, Thomas Christian

    2016-01-01

    The sensitivity of the adaptive model of the Athlete Biological Passport (ABP) and reticulocyte percentage (ret%) in detection of recombinant human erythropoietin (rHuEPO) misuse was evaluated using both a long-term normal dose and a brief high dose treatment regime. Sixteen subjects received...

  6. Recombinant human erythropoietin and hemoglobin concentration at operation and during the postoperative period

    DEFF Research Database (Denmark)

    Qvist, N; Boesby, S; Wolff, B

    1999-01-01

    In a double-blind placebo-controlled study we investigated the effect of recombinant human erythropoietin (r-HuEPO), on the perioperative hemoglobin concentration and the use of blood transfusions in patients undergoing elective colorectal surgery with a preoperative hemoglobin level

  7. Study of the erythropoiesis activity of nano-encapsulated forms of erythropoietin

    Directory of Open Access Journals (Sweden)

    Zhanagul Khasenbekova

    2014-01-01

    Full Text Available Introduction: The recombinant human erythropoietin (rhEPO is used in the treatment of anemia. In order to improve its pharmacokinetic properties, nanoparticles of biodegradable polymers of natural or synthetic origin were used. The aim of this study was to investigate the effect of new nano-encapsulated forms of recombinant human erythropoietin for oral use on the erythropoiesis in the cyclophosphamide immunosuppression model. Material and methods: The CHOpE immortalized cells culture (a primary producer of rhEPO "Vector" in Russia was used. The following biodegradable polymers were chosen: 0.05% and 0.005% carbopol, 0.05% and 0.005% kollidon, and 0.05% and 0.005% pectin. Immunosuppression was obtained by a single dose of i.p. injection of cyclophosphamide (250 mg/kg in white mice (18-20 g. During the next 5 days, the nano-encapsulated erythropoietin (100 ED/mouse was administered orally to each mouse. After 5 and 10 days, the cell count of the number of blood reticulocytes and the myelogram of bone marrow were performed. The control group of mice received injections of Eprex. Results: On the 5th day of the experiment, the highest level of reticulocyte was observed in the samples of erythropoietin with kollidon (0.05% and pectin (0.005% nanoparticles. On the 10th day, the highest activity was observed in the samples of erythropoietin substance with pectin at 0.05% and 0.005% concentrations. The levels of reticulocytes in these groups reached 13.53% and 14.55%, respectively. The results of the myelogram during immunosuppression showed some activity of erythropoietin in conjunction with both concentrations of pectin when a two-fold increase in the number of erythroblasts was observed on the 5th day. High degrees of erythrokaryocytes in the state of mitosis were observed in the 0.05% pectin samples. Similar results were observed in equivalent groups of control animals on the 10th day of the experiment, which is compatible with the data on Eprex

  8. VEGF gene polymorphisms and outcome of epithelial ovarian cancer patients.

    Science.gov (United States)

    Camerin, Gabriela Ribeiro; Brito, Angelo Borsarelli Carvalho; Vassallo, José; Derchain, Sophie Françoise Mauricette; Lima, Carmen Silvia Passos

    2017-02-01

    Since VEGF polymorphisms were associated with variable protein production, we analyzed herein their roles in outcome of epithelial ovarian cancer (EOC) patients. Genotypes of 85 patients with primary EOC were identified in DNA by real-time PCR. Progression-free survival and overall survival were analyzed using Kaplan-Meier method, univariate Cox model and bootstrap resampling study. At 60 months of follow-up, progression-free survival was shorter in patients with VEGF c.-2578 CC genotype compared with others (52.7 vs 82.2%; p = 0.04). Those patients had 2.15 more chance of presenting disease progression than others (p = 0.04); bootstrap study validated the result (p = 0.03). Our data suggest that VEGF c.-2578C>A polymorphism acts as a prognostic factor in EOC.

  9. Aberrant phenotypes of transgenic mice expressing dimeric human erythropoietin

    Directory of Open Access Journals (Sweden)

    Yun Seong-Jo

    2012-01-01

    Full Text Available Abstract Background Dimeric human erythropoietin (dHuEPO peptides are reported to exhibit significantly higher biological activity than the monomeric form of recombinant EPO. The objective of this study was to produce transgenic (tg mice expressing dHuEPO and to investigate the characteristics of these mice. Methods A dHuEPO-expressing vector under the control of the goat beta-casein promoter, which produced a dimer of human EPO molecules linked by a 2-amino acid peptide linker (Asp-Ile, was constructed and injected into 1-cell fertilized embryos by microinjection. Mice were screened using genomic DNA samples obtained from tail biopsies. Blood samples were obtained by heart puncture using heparinized tubes, and hematologic parameters were assessed. Using the microarray analysis tool, we analyzed differences in gene expression in the spleens of tg and control mice. Results A high rate of spontaneous abortion or death of the offspring was observed in the recipients of dHuEPO embryos. We obtained 3 founder lines (#4, #11, and #47 of tg mice expressing the dHuEPO gene. However, only one founder line showed stable germline integration and transmission, subsequently establishing the only transgenic line (#11. We obtained 2 F1 mice and 3 F2 mice from line #11. The dHuEPO protein could not be obtained because of repeated spontaneous abortions in the tg mice. Tg mice exhibited symptoms such as short lifespan and abnormal blood composition. The red blood cell count, white blood cell count, and hematocrit levels in the tg mice were remarkably higher than those in the control mice. The spleens of the tg mice (F1 and F2 females were 11- and -21-fold larger than those of the control mice. Microarray analysis revealed 2,672 spleen-derived candidate genes; more genes were downregulated than upregulated (849/764. Reverse transcriptase-polymerase chain reaction (RT-PCR and quantitative real-time PCR (qRT-PCR were used for validating the results of the microarray

  10. Prolonged presence of VEGF promotes vascularization in 3D bioprinted scaffolds with defined architecture

    NARCIS (Netherlands)

    Poldervaart, Michelle T; Gremmels, Hendrik; van Deventer, Kelly; Fledderus, Joost O; Oner, F Cumhur; Verhaar, Marianne C; Dhert, Wouter J A; Alblas, Jacqueline

    2014-01-01

    Timely vascularization is essential for optimal performance of bone regenerative constructs. Vascularization is efficiently stimulated by vascular endothelial growth factor (VEGF), a substance with a short half-life time. This study investigates the controlled release of VEGF from gelatin

  11. Recombinant Goat VEGF164 Increases Hair Growth by Painting Process on the Skin of Shaved Mouse

    Directory of Open Access Journals (Sweden)

    Wenlei Bao

    2014-09-01

    Full Text Available To detect goat vascular endothelial growth factor (VEGF-mediated regrowth of hair, full-length VEGF164 cDNA was cloned from Inner Mongolia cashmere goat (Capra hircus into the pET-his prokaryotic expression vector, and the recombinant plasmid was transferred into E. coli BL21 cells. The expression of recombinant 6×his-gVEGF164 protein was induced by 0.5 mM isopropyl thio-β-D-galactoside at 32°C. Recombinant goat VEGF164 (rgVEGF164 was purified and identi ed by western blot using monoclonal anti-his and anti-VEGF antibodies. The rgVEGF164 was smeared onto the dorsal area of a shaved mouse, and we noted that hair regrowth in this area was faster than in the control group. Thus, rgVEGF164 increases hair growth in mice.

  12. Erythropoietin Attenuates Pulmonary Vascular Remodeling in Experimental Pulmonary Arterial Hypertension through Interplay between Endothelial Progenitor Cells and Heme Oxygenase

    NARCIS (Netherlands)

    van Loon, Rosa Laura E; Bartelds, Beatrijs; Wagener, Frank A D T G; Affara, Nada; Mohaupt, Saffloer; Wijnberg, Hans; Pennings, Sebastiaan W C; Takens, Janny; Berger, Rolf M F

    2015-01-01

    BACKGROUND: Pulmonary arterial hypertension (PAH) is a pulmonary vascular disease with a high mortality, characterized by typical angio-proliferative lesions. Erythropoietin (EPO) attenuates pulmonary vascular remodeling in PAH. We postulated that EPO acts through mobilization of endothelial

  13. Pharmacokinetics and tolerability of cediranib, a potent VEGF signalling inhibitor, in cancer patients with hepatic impairment

    DEFF Research Database (Denmark)

    van Herpen, Carla M L; Lassen, Ulrik; Desar, Ingrid M E

    2013-01-01

    Vascular endothelial growth factor (VEGF) signalling plays a key role in tumour angiogenesis. Cediranib (AZD2171) is a small-molecule VEGF signalling inhibitor with potent activity against all three VEGF receptors. In this phase I, open-label, parallel-group study, adults with advanced solid...

  14. Biological variations in plasma VEGF and VEGFR-1 may compromise their biomarker value in colorectal cancer

    DEFF Research Database (Denmark)

    Svendsen, Mads N.; Brunner, Nils; Christensen, Ib Jarle

    2010-01-01

    Vascular Endothelial Growth Factor (VEGF) plays a prominent role in tumor angiogenesis and plasma VEGF concentration may carry prognostic information in colorectal cancer. The VEGF receptor 1 (VEGFR-1) is a regulatory receptor which is shredded into plasma of patients with colorectal cancer. For ...

  15. In vivo VEGF imaging with radiolabeled bevacizumab in a human ovarian tumor xenograft

    NARCIS (Netherlands)

    Nagengast, Wouter B.; Hospers, Geke A.; Mulder, Nanno H.; de Jong, Johan R.; Hollema, Harry; Brouwers, Adrienne H.; van Dongen, Guns A.; Perk, Lars R.; Lub-de Hooge, Marjolijn N.

    Vascular endothelial growth factor (VEGF), released by tumor cells, is an important growth factor in tumor angiogenesis. The humanized monoclonal antibody bevacizumab blocks VEGF-induced tumor angiogenesis by binding, thereby neutralizing VEGF. Our aim was to develop radiolabeled bevacizumab for

  16. VEGF Polymorphisms Are Associated With Endocardial Cushion Defects : A Family-Based Case-Control Study

    NARCIS (Netherlands)

    Smedts, Huberdina P. M.; Isaacs, Aaron; de Costa, Dominique; Uitterlinden, Andre G.; van Duijn, Cornelia M.; Gittenberger-de Groot, Adriana C.; Helbing, Willem A.; Steegers, Eric A. P.; Steegers-Theunissen, Regina P. M.

    Endocardial cushion defects (ECDs) of the cardiac outflow tract are among the most common congenital heart disease phenotypes. VEGF is essential for endocardial cushion formation and derangements in VEGF synthesis lead to ECD. Three functional single nucleotide polymorphisms (SNPs) in the VEGF gene

  17. VEGF expression and microvascular density in relation to high-risk ...

    African Journals Online (AJOL)

    VEGF expression and microvascular density in relation to high-risk-HPV infection in cervical carcinoma – An immunohistochemical study. ... Eleven cases were low grade and 19 were high-grade cases. VEGF expression was detected in 100% of cases. The relation between carcinoma grade and VEGF expression and ...

  18. Genetic variations in VEGF and VEGFR2 and glioblastoma outcome

    DEFF Research Database (Denmark)

    Sjöström, S; Wibom, C; Andersson, U

    2011-01-01

    significantly associated to survival, namely rs2071559 and rs12502008. However, these results are likely to be false positives due to multiple testing and could not be confirmed in a separate dataset. Overall, this study provides little evidence that VEGF and VEGFR2 polymorphisms are important for glioblastoma...

  19. Genetic variations in VEGF and VEGFR2 and glioblastoma outcome

    DEFF Research Database (Denmark)

    Sjöström, S; Wibom, C; Andersson, U

    2010-01-01

    significantly associated to survival, namely rs2071559 and rs12502008. However, these results are likely to be false positives due to multiple testing and could not be confirmed in a separate dataset. Overall, this study provides little evidence that VEGF and VEGFR2 polymorphisms are important for glioblastoma...

  20. Elevated serum and tissue VEGF associated with poor outcome in ...

    African Journals Online (AJOL)

    Serum and tissue vascular endothelial growth factor was strongly associated with grade III tumor, large tumor size, positive lymph node, negative hormone receptor status, +ve HER2 neu and poor survival, the data of the present study showed significant increase in mean serum level of VEGF in patients with positive ...

  1. (VEGF) expression in rats with spinal cord injury by transplantation ...

    African Journals Online (AJOL)

    User

    2011-05-16

    May 16, 2011 ... was quantified by means of western blot and immunohistochemistry technology. It was found that .... 0.6× volume of isopropyl alcohol and a 0.1× volume of 3 M sodium ... To detect expression and localization of VEGF in spinal cord tissue, .... ischemic brain (Chen et al., 2003) have provided their beneficial ...

  2. Thrombospondin-1 and VEGF in inflammatory bowel disease | Alkim ...

    African Journals Online (AJOL)

    Background and aim: Angiogenesis is an important process in the pathogenesis of chronic inflammation. We aimed to study the angiogeneic balance in inflammatory bowel disease (IBD) by evaluating the expression of vascular endothelial growth factor (VEGF) and thrombospondin-1 (TSP-1) on colonic epithelial cells, ...

  3. Incorporation of Ortho- and Meta-Tyrosine Into Cellular Proteins Leads to Erythropoietin-Resistance in an Erythroid Cell Line

    Directory of Open Access Journals (Sweden)

    Esztella Mikolás

    2014-04-01

    Full Text Available Background/Aims: Erythropoietin-resistance is an unsolved concern in the treatment of renal anaemia. We aimed to investigate the possible role of ortho- and meta-tyrosine - the hydroxyl free radical products of L-phenylalanine - in the development of erythropoietin-resistance. Methods: TF-1 erythroblast cell line was used. Cell concentration was determined on day 1; 2 and 3 by two independent observers simultaneously in Bürker cell counting chambers. Protein concentration was determined with colorimetric method. Para-, ortho- and meta-tyrosine levels were measured using reverse phase-HPLC with fluorescence detection. Using Western blot method activating phosphorylation of STAT5 and ERK1/2 were investigated. Results: We found a time- and concentration-dependent decrease of erythropoietin-induced proliferative activity in case of ortho- and meta-tyrosine treated TF-1 erythroblasts, compared to the para-tyrosine cultured cells. Decreased erythropoietin-response could be regained with a competitive dose of para-tyrosine. Proteins of erythroblasts treated by ortho- or meta-tyrosine had lower para-tyrosine and higher ortho- or meta-tyrosine content. Activating phosphorylation of ERK and STAT5 due to erythropoietin was practically prevented by ortho- or meta-tyrosine treatment. Conclusion: According to this study elevated ortho- and meta-tyrosine content of erythroblasts may lead to the dysfunction of intracellular signaling, resulting in erythropoietin-hyporesponsiveness.

  4. Protective effects of erythropoietin against cuprizone-induced oxidative stress and demyelination in the mouse corpus callosum

    Directory of Open Access Journals (Sweden)

    Iraj Ragerdi Kashani

    2017-08-01

    Full Text Available Objective(s: Increasing evidence in both experimental and clinical studies suggests that oxidative stress plays a major role in the pathogenesis of multiple sclerosis. The aim of the present work is to investigate the protective effects of erythropoietin against cuprizone-induced oxidative stress. Materials and Methods: Adult male C57BL/6J mice were fed a chow containing 0.2 % cuprizone for 6 weeks. After 3 weeks, mice were simultaneously treated with erythropoietin (5,000 IU/ kg body weight by daily intraperitoneal injections. Results: Our results showed that cuprizone induced oxidative stress accompanied with down-regulation of subunits of the respiratory chain complex and demyelination of corpus callosum. Erythropoietin antagonized these effects. Biochemical analysis showed that oxidative stress induced by cuprizone was regulated by erythropoietin. Similarly, erythropoietin induced the expression of subunits of the respiratory chain complex over normal control values reflecting a mechanism to compensate cuprizone-mediated down-regulation of these genes. Conclusion: The data implicate that erythropoietin abolishes destructive cuprizone effects in the corpus callosum by decreasing oxidative stress and restoring mitochondrial respiratory enzyme activity.

  5. ScVEGF-PEG-HBED-CC and scVEGF-PEG-NOTA conjugates: comparison of easy-to-label recombinant proteins for [{sup 68}Ga]PET imaging of VEGF receptors in angiogenic vasculature

    Energy Technology Data Exchange (ETDEWEB)

    Eder, Matthias [German Cancer Research Center (DKFZ), 69120 Heidelberg (Germany)], E-mail: m.eder@dkfz.de; Krivoshein, Arcadius V.; Backer, Marina; Backer, Joseph M. [SibTech, Inc., Brookfield, CT 06804 (United States); Haberkorn, Uwe [Department of Nuclear Medicine, University of Heidelberg, 69120 Heidelberg (Germany); Eisenhut, Michael [German Cancer Research Center (DKFZ), 69120 Heidelberg (Germany)

    2010-05-15

    Introduction: VEGF receptors play a key role in angiogenesis and are important targets for several approved and many experimental drugs. Imaging of VEGF receptor expression in malignant tumors would provide important information, which can influence patient management. The aim of this study was the development of an easy-to-label positron-emitting tracer for imaging VEGF receptors. The tracer is based on engineered single-chain VEGF (scVEGF), expressed with cysteine-containing fusion tag (Cys-tag) for site-specific conjugation of PEGylated bifunctional chelating agents, HBED-CC or NOTA, suitable for labeling with {sup 68}Ga at ambient temperature. Methods: scVEGF-PEG-HBED-CC was synthesized by activating a single carboxyl group of the [Fe(HBED-CC)]{sup -} complex with N-hydroxysuccinimide. Reaction of the activated complex with NH{sub 2}-PEG-maleimide was followed by site-specific conjugation of PEGylated chelator to a thiol group in Cys-tag of scVEGF. The scVEGF-PEG-NOTA conjugate was synthesized using NHS-PEG-maleimide and p-NH{sub 2}-Bn-NOTA. {sup 68}Ga complexation was performed in HEPES buffer (pH 4.2) at room temperature. The functional activity after labeling was tested by radioligand cell binding assays. Biodistribution and PET studies in tumor-bearing mice were performed after 1, 2, 3 and 4 h postinjection. Results: The radiolabeling of scVEGF-PEG-HBED-CC proved more efficient than scVEGF-PEG-NOTA allowing to stop the reaction after 4 min (>97% radiochemical yield). Radioligand cell binding assays performed on HEK-293 cells overexpressing VEGFR-2 revealed no change in the binding properties of {sup 68}Ga-radiolabeled scVEGF relative to other scVEGF-based tracers. Both tracers showed comparable results in biodistribution, such as tumor accumulation and low liver uptake. The tracers were stable in 50% human serum for at least 72 h. Conclusions: The conjugates scVEGF-PEG-HBED-CC and scVEGF-PEG-NOTA revealed comparable in vivo characteristics and allowed easy

  6. The prognosis was poorer in colorectal cancers that expressed both VEGF and PROK1 (No correlation coefficient between VEGF and PROK1).

    Science.gov (United States)

    Goi, Takanori; Nakazawa, Toshiyuki; Hirono, Yasuo; Yamaguchi, Akio

    2015-10-06

    The angiogenic proteins vascular endothelial growth factor (VEGF) and prokineticin1 (PROK1) proteins are considered important in colorectal cancer, the relationship between their simultaneous expression and prognosis was investigated in the present study. VEGF and PROK1 expression in 620 primary human colorectal cancer lesions was confirmed via immunohistochemical staining with anti-VEGF and anti-PROK1 antibodies, and the correlation between the expression of these 2 proteins and recurrence/prognosis were investigated. VEGF protein was expressed in 329 (53.1%) and PROK1 protein was expressed in 223 (36.0%). PROK1 and VEGF were simultaneously expressed in 116 (18.7%) of the 620 cases. The correlation coefficient between VEGF expression and PROK1 expression was r = 0.11, and therefore correlation was not observed. Clinical pathology revealed that substantially lymphnode matastasis, hematogenous metastasis, or TMN advanced-stage IV was significantly more prevalent in cases that expressed both VEGF and PROK1 than in the cases negative for both proteins or those positive for only 1 of the proteins. Also the cases positive for both proteins exhibited the worst recurrence and prognosis. In the Cox proportional hazards model, VEGF and PROK1 expression was an independent prognostic factor. The prognosis was poorer in colorectal cancers that expressed both PROK1 and VEGF relative to the cases that expressed only 1 protein, and the expression of both proteins was found to be an independent prognostic factor.

  7. Lectin-binding assays for the isoforms of human erythropoietin: comparison of urinary and four recombinant erythropoietins.

    Science.gov (United States)

    Storring, P L; Tiplady, R J; Gaines Das, R E; Rafferty, B; Mistry, Y G

    1996-09-01

    Assays have been developed for the isoforms of erythropoietin (EPO) based on their binding to eight different lectins. These assays were used to compare the isoform compositions of two preparations of human urinary EPO (uEPO) and four preparations of recombinant DNA-derived human EPO (rEPO), which had been shown to differ in their biological and immunological properties and in their isoform composition as judged by isoelectric focusing and electrophoresis. Agarose-bound Ricinus communis agglutinin I (RCA), Erythrina cristagalli agglutinin (ECA), Maackia amurensis leukoagglutinin (MAL), Sambucus nigra agglutinin (SNA), Lycopersicon esculentum agglutinin (LEA), concanavalin A (Con A), Phaseolus vulgaris agglutinin-L4 (L-PHA) and Agaricus bisporus agglutinin (ABA) were used to bind EPO isoforms possessing: N-glycans containing non-sialylated outer Gal beta 1-4GlcNAc (RCA and ECA), NeuAc alpha 2-3Gal beta 1-4GlcNAc (MAL), NeuAc alpha 2-6Gal (SNA), or repeating Gal beta 1-4GlcNAc sequences (LEA); biantennary N-glycans (Con A); tetraantennary and 2,6-branched triantennary N-glycans (L-PHA); and O-glycans containing NeuAc alpha 2-6GalNAc (SNA) and Gal beta 1-3GalNAc (ABA). Free EPO was measured by mouse spleen cell bioassay or immunoassay. Estimates from most lectin-binding assays were reproducible between assays and batches of lectin-agarose, although batches of MAL- and ABA-agarose, and to a lesser extent LEA-agarose, differed in their EPO-binding. Lectin-binding assays showed differences between the isoform compositions of all EPOs, including the two Chinese hamster ovary cell-derived rEPOs, with RCA- and ECA-binding assays being the most discriminating. Lectin-binding estimates provided evidence that uEPO differs from these rEPOs in its lower content of isoforms with biantennary N-glycans and higher content of those with multiantennary N-glycans, and in its lower content of isoforms with N-glycans possessing repeating Gal beta 1-4GlcNAc sequences and of those with O

  8. Mesenchymal stem cells protect cigarette smoke-damaged lung and pulmonary function partly via VEGF-VEGF receptors.

    Science.gov (United States)

    Guan, Xiao-Jun; Song, Lin; Han, Feng-Feng; Cui, Zhi-Lei; Chen, Xi; Guo, Xue-Jun; Xu, Wei-Guo

    2013-02-01

    Progressive pulmonary inflammation and emphysema have been implicated in the progression of chronic obstructive pulmonary disease (COPD), while current pharmacological treatments are not effective. Transplantation of bone marrow mesenchymal stem cells (MSCs) has been identified as one such possible strategy for treatment of lung diseases including acute lung injury (ALI) and pulmonary fibrosis. However, their role in COPD still requires further investigation. The aim of this study is to test the effect of administration of rat MSCs (rMSCs) on emphysema and pulmonary function. To accomplish this study, the rats were exposed to cigarette smoke (CS) for 11 weeks, followed by administration of rMSCs into the lungs. Here we show that rMSCs infusion mediates a down-regulation of pro-inflammatory mediators (TNF-α, IL-1β, MCP-1, and IL-6) and proteases (MMP9 and MMP12) in lung, an up-regulation of vascular endothelial growth factor (VEGF), VEGF receptor 2, and transforming growth factor (TGFβ-1), while reducing pulmonary cell apoptosis. More importantly, rMSCs administration improves emphysema and destructive pulmonary function induced by CS exposure. In vitro co-culture system study of human umbilical endothelial vein cells (EA.hy926) and human MSCs (hMSCs) provides the evidence that hMSCs mediates an anti-apoptosis effect, which partly depends on an up-regulation of VEGF. These findings suggest that MSCs have a therapeutic potential in emphysematous rats by suppressing the inflammatory response, excessive protease expression, and cell apoptosis, as well as up-regulating VEGF, VEGF receptor 2, and TGFβ-1. Copyright © 2012 Wiley Periodicals, Inc.

  9. Erythropoietin resistance in end-stage renal disease patient with gastric antral vascular ectasia

    Directory of Open Access Journals (Sweden)

    Desiree Ji Re Lee

    2015-09-01

    Full Text Available AbstractWe observed a case of recombinant human erythropoietin resistance caused by Gastric Antral Vascular Ectasia in a 40-year-old female with ESRD on hemodialysis. Some associated factors such as autoimmune disease, hemolysis, heart and liver disease were discarded on physical examination and complementary tests. The diagnosis is based on the clinical history and endoscopic appearance of watermelon stomach. The histologic findings are fibromuscular proliferation and capillary ectasia with microvascular thrombosis of the lamina propria. However, these histologic findings are not necessary to confirm the diagnosis. Gastric Antral Vascular Ectasia is a serious condition and should be considered in ESRD patients on hemodialysis with anemia and resistance to recombinant human erythropoietin because GAVE is potentially curable with specific endoscopic treatment method or through surgical procedure.

  10. Erythropoietin may reduce the risk of germ cell loss in boys with cryptorchidism

    DEFF Research Database (Denmark)

    Cortes, D; Visfeldt, J; Thorup, J M

    2001-01-01

    of infertility. In order to increase the number of germ cells, and thereby the fertility potential, additional hormonal therapy has been attempted before surgery. In a study, small doses of the gonadotropin-releasing hormone analogue buserelin before orchiopexy caused higher values. Others have found......: Erythropoietin (Eprex) 100 IU/kg were administered subcutaneously weekly for 3 months prior to surgery in two cryptorchid boys, 6 months old and 1 year 9 months old, respectively, with renal function impairment. RESULTS: The number of spermatogonia per tubular cross-section in testicular biopsies was unusually...... that hormonal treatment with human chorionic gonadotropin or gonadotropin releasing hormone analogue may harm the germ cells in cryptorchidism. The aim of the study is to demonstrate that additional hormonal therapy with erythropoietin has a positive effect on the number of germ cells. MATERIALS AND METHODS...

  11. VEGF-A isoforms program differential VEGFR2 signal transduction, trafficking and proteolysis

    Directory of Open Access Journals (Sweden)

    Gareth W. Fearnley

    2016-05-01

    Full Text Available Vascular endothelial growth factor A (VEGF-A binding to the receptor tyrosine kinase VEGFR2 triggers multiple signal transduction pathways, which regulate endothelial cell responses that control vascular development. Multiple isoforms of VEGF-A can elicit differential signal transduction and endothelial responses. However, it is unclear how such cellular responses are controlled by isoform-specific VEGF-A–VEGFR2 complexes. Increasingly, there is the realization that the membrane trafficking of receptor–ligand complexes influences signal transduction and protein turnover. By building on these concepts, our study shows for the first time that three different VEGF-A isoforms (VEGF-A165, VEGF-A121 and VEGF-A145 promote distinct patterns of VEGFR2 endocytosis for delivery into early endosomes. This differential VEGFR2 endocytosis and trafficking is linked to VEGF-A isoform-specific signal transduction events. Disruption of clathrin-dependent endocytosis blocked VEGF-A isoform-specific VEGFR2 activation, signal transduction and caused substantial depletion in membrane-bound VEGFR1 and VEGFR2 levels. Furthermore, such VEGF-A isoforms promoted differential patterns of VEGFR2 ubiquitylation, proteolysis and terminal degradation. Our study now provides novel insights into how different VEGF-A isoforms can bind the same receptor tyrosine kinase and elicit diverse cellular outcomes.

  12. Cancer-Associated Systemic Syndrome (CASS:The Mechanism of VEGF in Tumor-Bearing Mice

    Directory of Open Access Journals (Sweden)

    Fang CHEN

    2009-04-01

    Full Text Available Background and objective VEGF plays an important role in the development of cancer. The aim of this study is to observe the structural alterations in multiple organs of high VEGF expression mice, and insight into the role of tumor-derived VEGF in the development of CASS. Methods Murine fibrosarcoma of T241-VEGF and T241- Vector tumor cells were transplanted subcutaneously in mice to construct the xenograft tumor model. The mice gross examinations were observed and the percentage of survival animals in each group is presented. The level of hemoglobin, the numbers of erythrocytes and serum concentration of VEGF in peripheral blood were analyzed. Histological analysis of liver, spleen, adrenal gland and bone-marrow were applied. Vascular networks in tumors were analyzed under a confocal microscope. Results The VEGF-expressing tumor bearing mice manifested CASS by severe anemia, hepatosplenomegaly and loss of body weight. The survival rate of mice was decreased. The level of hemoglobin and erythrocytes in circulating blood were significantly reduced (P<0.01, with the increased serum concentration of VEGF. The blood vessels of tumorappeared as primitive and dilated sinusoidal vascular structures. Conclusion The tumor-produced VEGF affect multiple tissues, organs and resulted in CASS in mice model. It suggest that VEGF might be involved in the occurrence and development of CASS. It might be helpful for anti-VEGF therapy in clinical CASS and combing anti-VEGF therapy in advanced cancer patients.

  13. VEGF increases the permeability of sheep pleura ex vivo through VEGFR2 stimulation.

    Science.gov (United States)

    Peppa, Vasiliki I; Arsenopoulou, Zoi V; Zarogiannis, Sotirios G; Deligiorgi, Triantafyllia; Jagirdar, Rajesh; Makantasis, Ioannis; Stefanidis, Ioannis; Liakopoulos, Vassilios; Molyvdas, Paschalis-Adam; Gourgoulianis, Konstantinos I; Hatzoglou, Chrissi

    2014-10-01

    Vascular endothelial growth factor (VEGF), a cytokine that increases vascular permeability to water and proteins and induces angiogenesis, has been implicated in the development of pleural effusions. Inflammatory and malignant pleural effusions are rich in VEGF content while mesothelial cells produce and excrete VEGF. In this report we aimed at investigating by means of electrophysiology the direct effects of VEGF on the parietal and visceral sheep pleura as well as the type of receptors that mediate this effect. Our findings show that VEGF has a direct effect on the pleural mesothelium rendering it more permeable and this effect is mediated through the stimulation of VEGF receptor 2. Our findings shed more light to the role of VEGF in the pathogenesis of pleural effusions and provide functional evidence for a role of VEGFR2 on the pleural mesothelium that has never been studied before. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Intraosseous Erythropoietin for Acute Tissue Protection in Battlefield Casualties Suffering Hypovolemic Shock

    Science.gov (United States)

    2013-11-01

    Reserve University, Cleveland, OH. 2002 Acute Complications of Pericardial Disease or Injury. February 19th. Acute Complications of Diabetes Mellitus...Chile. [Arterial and venous prostagladin E2 levels in patients with valvular disease ]. Guarda E, Zamorano B, Gazmuri RJ, Escobar E. 1988 Best...AD Award Number: W81XWH-11-2-0019 TITLE: “Intraosseous Erythropoietin for Acute Tissue Protection in Battlefield Casualties

  15. Erythropoietin in patients with aneurysmal subarachnoid haemorrhage: a double blind randomised clinical trial

    DEFF Research Database (Denmark)

    Springborg, J B; Møller, C; Gideon, P

    2007-01-01

    BACKGROUND: Erythropoietin (EPO) is neuroprotective in experimental models of stroke and subarachnoid haemorrhage (SAH) and possibly in patients with thromboembolic stroke. We studied the efficacy and safety of EPO in patients with SAH. METHODS: A larger scale clinical trial was planned...... no statistically significant group differences in the primary or secondary outcome measures. EPO was well tolerated. CONCLUSIONS: Beneficial effects of EPO in patients with SAH cannot be excluded or concluded on the basis of this study and larger scale trials are warranted....

  16. Erythropoietin in the critically ill: do we ask the right questions?

    OpenAIRE

    McCook, Oscar; Georgieff, Michael; Scheuerle, Angelika; M?ller, Peter; Thiemermann, Christoph; Radermacher, Peter

    2012-01-01

    There is a plethora of experimental data on the potential therapeutic benefits of recombinant human erythropoietin (rhEPO) and its synthetic derivatives in critical care medicine, in particular in ischemia/reperfusion injury. Most of the recent clinical trials have not shown clear benefits, and, in some patients, EPO-aggravated morbidity and mortality was even reported. Treatment with rhEPO has been successfully used in patients with anemia resulting from chronic kidney disease, but even a su...

  17. Influence of Li+ charge compensator ion on the energy transfer from Pr3 + to Gd3 + ions in Ca9Mg(PO4)6F2:Gd3 +, Pr3 +, Li+ phosphor

    Science.gov (United States)

    Tamboli, Sumedha; Dhoble, S. J.

    2017-09-01

    Phototherapy is a renowned treatment for curing skin diseases since ancient times. Phototherapeutic treatment for psoriasis and many other diseases require narrow band ultra violet-B (NB-UVB) light with peak intensity at 313 nm to be exposed to the affected part of body. In this paper, we report combustion synthesis of NB-UVB - 313 nm emitting Ca9Mg(PO4)6F2 phosphors doped with Gd3 +, Pr3 + and Li+ ions. The phase formation was confirmed by obtaining X-ray diffraction (XRD) pattern and morphology was studied with the Scanning electron microscopy (SEM) images. Photoluminescence (PL) emission spectra show intense narrow band emission at 313 nm under 274 nm excitation wavelengths. Emission intensity was enhanced when Ca9Mg(PO4)6F2 compound is co-doped with Pr3 + ions. Excitation spectra of Ca9Mg(PO4)6F2:Gd3 +, Pr3 + doped samples shows broad excitation in ultra violet C (UVC) region. Diffuse reflectance spectra (DRS), obtained by UV-visible spectrophotometer, measures the absorption properties of the material. By applying Kubelka Munk function on the diffuse reflectance spectra, band gap of the material is determined. PL decay curves were examined which indicates efficient energy transfer between Pr3 + and Gd3 + ions. Charge compensation effect was also studied by co-doping Li+ ion in host. Emission intensity was found to increase with the addition of charge compensator. The prepared phosphor has potential to convert UVC light into NB-UVB. The luminescence intensity of Gd3 + shows remarkable increase when it is sensitized with Pr3 +, and an addition of charge compensator in the form of Li+, show even better results. This phosphor surely has the potential to be used as phototherapy lamp phosphor.

  18. Influence of Li+charge compensator ion on the energy transfer from Pr3+to Gd3+ions in Ca9Mg(PO4)6F2:Gd3+, Pr3+, Li+phosphor.

    Science.gov (United States)

    Tamboli, Sumedha; Dhoble, S J

    2017-09-05

    Phototherapy is a renowned treatment for curing skin diseases since ancient times. Phototherapeutic treatment for psoriasis and many other diseases require narrow band ultra violet-B (NB-UVB) light with peak intensity at 313nm to be exposed to the affected part of body. In this paper, we report combustion synthesis of NB-UVB -313nm emitting Ca 9 Mg(PO 4 ) 6 F 2 phosphors doped with Gd 3+ , Pr 3+ and Li + ions. The phase formation was confirmed by obtaining X-ray diffraction (XRD) pattern and morphology was studied with the Scanning electron microscopy (SEM) images. Photoluminescence (PL) emission spectra show intense narrow band emission at 313nm under 274nm excitation wavelengths. Emission intensity was enhanced when Ca 9 Mg(PO 4 ) 6 F 2 compound is co-doped with Pr 3+ ions. Excitation spectra of Ca 9 Mg(PO 4 ) 6 F 2 :Gd 3+ , Pr 3+ doped samples shows broad excitation in ultra violet C (UVC) region. Diffuse reflectance spectra (DRS), obtained by UV-visible spectrophotometer, measures the absorption properties of the material. By applying Kubelka Munk function on the diffuse reflectance spectra, band gap of the material is determined. PL decay curves were examined which indicates efficient energy transfer between Pr 3+ and Gd 3+ ions. Charge compensation effect was also studied by co-doping Li + ion in host. Emission intensity was found to increase with the addition of charge compensator. The prepared phosphor has potential to convert UVC light into NB-UVB. The luminescence intensity of Gd 3+ shows remarkable increase when it is sensitized with Pr 3+ , and an addition of charge compensator in the form of Li + , show even better results. This phosphor surely has the potential to be used as phototherapy lamp phosphor. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Physician Education: The Erythropoietin Receptor and Signal Transduction.

    Science.gov (United States)

    Yoshimura; Arai

    1996-01-01

    ERYTHROPOIETIN (EPO): Erythropoietin (EPO) is a hormone that promotes the proliferation and differentiation of erythroid progenitor cells and regulates the number of erythrocytes in peripheral blood. EPO is produced mainly by the kidneys, and transcription of the EPO gene is promoted by a reduction in the oxygen concentration in the blood. The existence of EPO was suggested near the end of the 19th century by the discovery that hypoxia increases the production of red blood cells. EPO was identified as a serum factor in the 1950s, and in 1970 Miyake and coworkers succeeded in purifying it by using the urine of patients with aplastic anemia as a starting material. The human EPO gene was cloned in 1985 using a partial amino acid sequence from this purified EPO, and it is well known that recombinant EPO is currently used as a drug to treat anemia associated with chronic renal failure and other illnesses. ACTION OF EPO: When human bone marrow cells are cultured in a semisolid medium containing EPO, they form small erythroblast colonies in five to seven days, and by day 10 large erythroblast colonies appear that resemble fireworks ("burst" colonies). The original cells in the former colonies are called colony forming units-erythroid (CFU-E) or late-stage erythroblast progenitor cells and in the latter colonies they are called burst forming units-erythroid (BFU-E) or early-stage erythroblast progenitor cells. As shown in Figure 1, red blood cells are produced through differentiation from stem cells to BFU-E, CFU-E, and erythroblasts. Although EPO acts on both BFU-E and CFU-E cells, CFU-E cells show greater sensitivity to EPO, and other factors such as stem cell factor (SCF), interleukin (IL)-3, IL-4, and granulocyte macrophage colony-stimulating factor (GM-CSF) must be present together with EPO for BFU-E cell proliferation. In erythroblasts beyond the CFU-E stage, sensitivity to EPO decreases as the cells mature. THE EPO RECEPTOR AND THE CYTOKINE RECEPTOR FAMILY: The EPO

  20. Effects of acute exercise on plasma erythropoietin levels in trained runners.

    Science.gov (United States)

    Bodary, P F; Pate, R R; Wu, Q F; McMillan, G S

    1999-04-01

    The purpose of this study was to investigate further the influence of exercise on erythropoietin. We observed the effects of high intensity running on plasma erythropoietin concentration in competitive distance runners. A repeated measures design was used to compare the responses of intermittent high intensity (HIGH) exercise to continuous moderate intensity (MOD) exercise and rest (REST). The HIGH treatment consisted of 60 min of exercise alternating 5 min of running at approximately 90% of VO2max with 5 min of brisk walking. The MOD treatment consisted of a continuous 60-min run on the treadmill at 60% of VO2max. Blood samples were collected immediately before the exercise (PRE), immediately following the exercise (POST), and 4 (heart rate (4HR), 12 (12HR), 24 (24HR), and 48 (48HR)) h following the exercise. The variables examined included plasma erythropoietin concentration ([EPO]), hemoglobin (Hb) concentration ([Hb]), hematocrit (Hct), red blood cell count (RBC), and mean corpuscular volume (MCV). ANOVA revealed the expected treatment-by-time interaction for Hct and [Hb] suggesting a hemodilution at 24 and 48 h postexercise for the MOD and HIGH treatments. However, no significant treatment-by-time interactions were observed for [EPO], RBC, or MCV. These results indicate that intermittent high intensity exercise does not have a significant effect on [EPO] in trained distance runners.

  1. Tratamiento con eritropoyetina humana recombinante Human recombinant erythropoietin therapy

    Directory of Open Access Journals (Sweden)

    Hugo Donato

    2006-02-01

    Full Text Available La eritropoyetina recombinante (rHuEPO se ha transformado en la citoquina más utilizada terapéuticamente en el mundo. Luego del éxito obtenido en pacientes con insuficiencia renal terminal, se pudo establecer la utilidad de la terapia con rHuEPO para mejorar otras anemias, incluso en pacientes pediátricos y neonatos. El tratamiento o la prevención de la anemia del prematuro mediante el uso de rHuEPO llevó a una significativa reducción en cantidad de transfusiones y en exposición a dadores. Aún debe establecerse una clara definición sobre cuáles niños prematuros deben recibir tratamiento rutinariamente. Otras indicaciones en período neonatal incluyen anemias hiporregenerativas y hemolíticas. La eficacia de la rHuEPO en niños mayores, con excepción de la insuficiencia renal crónica, no ha sido tan exhaustivamente evaluada como en adultos. Mientras que durante los últimos años se han realizado gran cantidad de estudios en adultos con anemia asociada al cáncer o a infección por HIV, permitiendo establecer conclusiones claras sobre su eficacia, sólo escasa cantidad de estudios con pequeño número de pacientes han sido realizados en niños. Hasta la fecha, los resultados sugieren que la terapia con rHuEPO en niños es tan útil como en adultos, pero la realización de estudios aleatorizados prospectivos incluyendo gran número de pacientes es esencial para alcanzar conclusiones definitivas. Los resultados de estudios dirigidos a evaluar la eficacia de la rHuEpo para mantener una dosis adecuada de ribavirina en pacientes en tratamiento por hepatitis C son alentadores. La utilización potencial de los efectos no hemopoyéticos de la rHuEPO en neonatos es un terreno novedoso y apasionante. El rol de la Epo como citoprotector para sistema nervioso central y mucosa intestinal está bajo investigación exhaustiva.Recombinant human erythropoietin (rHuEpo has become the most widely used cytokine in the world. Following the success of

  2. Neural crest cell-derived VEGF promotes embryonic jaw extension

    Science.gov (United States)

    Wiszniak, Sophie; Mackenzie, Francesca E.; Anderson, Peter; Kabbara, Samuela; Ruhrberg, Christiana; Schwarz, Quenten

    2015-01-01

    Jaw morphogenesis depends on the growth of Meckel’s cartilage during embryogenesis. However, the cell types and signals that promote chondrocyte proliferation for Meckel’s cartilage growth are poorly defined. Here we show that neural crest cells (NCCs) and their derivatives provide an essential source of the vascular endothelial growth factor (VEGF) to enhance jaw vascularization and stabilize the major mandibular artery. We further show in two independent mouse models that blood vessels promote Meckel’s cartilage extension. Coculture experiments of arterial tissue with NCCs or chondrocytes demonstrated that NCC-derived VEGF promotes blood vessel growth and that blood vessels secrete factors to instruct chondrocyte proliferation. Computed tomography and X-ray scans of patients with hemifacial microsomia also showed that jaw hypoplasia correlates with mandibular artery dysgenesis. We conclude that cranial NCCs and their derivatives provide an essential source of VEGF to support blood vessel growth in the developing jaw, which in turn is essential for normal chondrocyte proliferation, and therefore jaw extension. PMID:25922531

  3. VEGF Promotes Malaria-Associated Acute Lung Injury in Mice

    Science.gov (United States)

    Carapau, Daniel; Pena, Ana C.; Ataíde, Ricardo; Monteiro, Carla A. A.; Félix, Nuno; Costa-Silva, Artur; Marinho, Claudio R. F.; Dias, Sérgio; Mota, Maria M.

    2010-01-01

    The spectrum of the clinical presentation and severity of malaria infections is broad, ranging from uncomplicated febrile illness to severe forms of disease such as cerebral malaria (CM), acute lung injury (ALI), acute respiratory distress syndrome (ARDS), pregnancy-associated malaria (PAM) or severe anemia (SA). Rodent models that mimic human CM, PAM and SA syndromes have been established. Here, we show that DBA/2 mice infected with P. berghei ANKA constitute a new model for malaria-associated ALI. Up to 60% of the mice showed dyspnea, airway obstruction and hypoxemia and died between days 7 and 12 post-infection. The most common pathological findings were pleural effusion, pulmonary hemorrhage and edema, consistent with increased lung vessel permeability, while the blood-brain barrier was intact. Malaria-associated ALI correlated with high levels of circulating VEGF, produced de novo in the spleen, and its blockage led to protection of mice from this syndrome. In addition, either splenectomization or administration of the anti-inflammatory molecule carbon monoxide led to a significant reduction in the levels of sera VEGF and to protection from ALI. The similarities between the physiopathological lesions described here and the ones occurring in humans, as well as the demonstration that VEGF is a critical host factor in the onset of malaria-associated ALI in mice, not only offers important mechanistic insights into the processes underlying the pathology related with malaria but may also pave the way for interventional studies. PMID:20502682

  4. Role of VEGF family members and receptors in coronary vessel formation.

    Science.gov (United States)

    Tomanek, Robert J; Holifield, Jennifer S; Reiter, Rebecca S; Sandra, Alexander; Lin, Jim J-C

    2002-11-01

    The specific roles of vascular endothelial growth factor (VEGF) family members and their receptors (VEGFRs) in coronary vessel formation were studied. By using the quail heart explant model, we found that neutralizing antibodies to VEGF-B or VEGF-C inhibited tube formation on the collagen gel more than anti-VEGF-A. Soluble VEGFR-1, a receptor for VEGF-A and -B, inhibited tube formation by 87%, a finding consistent with that of VEGF-B inhibition. In contrast, addition of soluble VEGFR-2, a receptor for VEGF family members A, C, D, and E, inhibited tube formation by only 43%. Acidic FGF-induced tube formation dependency on VEGF was demonstrated by the attenuating effect of a soluble VEGFR-1 and -2 chimera. The localization of VEGF R-2 and R-3 was demonstrated by in situ hybridization of serial sections, which documented marked accumulations of transcripts for both receptors at the base of the truncus arteriosus coinciding with the temporal and spatial formation of the coronary arteries by means of ingrowth of capillary plexuses. This finding suggests that both VEGFR-2 and R-3 may play a role in the formation of the coronary artery roots. In summary, these experiments document a role for multiple members of the VEGF family and their receptors in formation of the coronary vascular bed. Copyright 2002 Wiley-Liss, Inc.

  5. Clinicopathological and prognostic significance of HER-2/neu and VEGF expression in colon carcinomas

    Directory of Open Access Journals (Sweden)

    Li Jing

    2011-06-01

    Full Text Available Abstract Background HER-2/neu and VEGF expression is correlated with disease behaviors in various cancers. However, evidence for their expression in colon cancer is rather contradictory both for the protein expression status and prognostic value. HER-2/neu is found to participate in VEGF regulation, and has known correlation with VEGF expression in some tumors. In this study, we investigated HER-2/neu and VEGF expression in Chinese colon patients and explored whether there was any correlation between their expression patterns. Methods HER-2/neu and VEGF were investigated immunohistochemically using tumor samples obtained from 317 colon cancer patients with all tumor stages. Correlation of the degree of staining with clinicopathological parameters and survival was investigated. Results Positive expression rates of HER-2/neu and VEGF in colon cancer were 15.5% and 55.5% respectively. HER-2/neu expression was significantly correlated with tumor size and distant metastases (P (P > 0.05. Expression of VEGF was significantly correlated with tumor size, tumor stage, lymph node metastases, and distant metastases (P (P = 0.146. No correlation between HER-2/neu and VEGF expression was detected (P = 0.151. Conclusions HER-2/neu and VEGF are not important prognostic markers of colon cancer. The present results do not support any association between HER2/neu and VEGF expression in this setting.

  6. Chronic hypoxia attenuates VEGF signaling and angiogenic responses by downregulation of KDR in human endothelial cells.

    Science.gov (United States)

    Olszewska-Pazdrak, Barbara; Hein, Travis W; Olszewska, Paulina; Carney, Darrell H

    2009-05-01

    Coronary artery disease results in progressive vascular stenosis associated with chronic myocardial ischemia. Vascular endothelial growth factor (VEGF) stimulates endothelial cell angiogenic responses to revascularize ischemic tissues; however, the effect of chronic hypoxia on the responsiveness of endothelial cells to VEGF remains unclear. We, therefore, investigated whether hypoxia alters VEGF-stimulated signaling and angiogenic responses in primary human coronary artery endothelial (HCAE) cells. Exposure of HCAE cells to hypoxia (1% O(2)) for 24 h decreased VEGF-stimulated endothelial cell migration ( approximately 82%), proliferation ( approximately 30%), and tube formation. Hypoxia attenuated VEGF-stimulated activation of endothelial nitric oxide (NO) synthase (eNOS) ( approximately 72%) and reduced NO production in VEGF-stimulated cells from 237 +/- 38.8 to 61.3 +/- 28.4 nmol/l. Moreover, hypoxia also decreased the ratio of phosphorylated eNOS to total eNOS in VEGF-stimulated cells by approximately 50%. This effect was not observed in thrombin-stimulated cells, suggesting that hypoxia specifically inhibited VEGF signaling upstream of eNOS phosphorylation. VEGF-induced activation of Akt, ERK1/2, p38, p70S6 kinases, and S6 ribosomal protein was also attenuated in hypoxic cells. Moreover, VEGF-stimulated phosphorylation of VEGF receptor-2 (KDR) at Y996 and Y1175 was decreased by hypoxia. This decrease correlated with a 70 +/- 12% decrease in KDR protein expression. Analysis of mRNA from these cells showed that hypoxia reduced steady-state levels of KDR mRNA by 52 +/- 16% and decreased mRNA stability relative to normoxic cells. Our findings demonstrate that chronic hypoxia attenuates VEGF-stimulated signaling in HCAE cells by specific downregulation of KDR expression. These data provide a novel explanation for the impaired angiogenic responses to VEGF in endothelial cells exposed to chronic hypoxia.

  7. The Effect of Erythropoietin on S100 Protein Expression in Cochlea After Acoustic Overstimulation: An Experimental Study

    Directory of Open Access Journals (Sweden)

    Gulsen Gurgen

    2014-03-01

    Full Text Available Aim: To investigate the effect of Erythropoietin on acoustically overstimulated rat spiral ganglion neurons (SGNs using S100 protein immunostaining.Material and Method: Twenty-two Wistar albino rats were divided into three groups: healthy control group (n=7, Saline solution (n=7 and Erythropoietin injection groups (n=8. Saline solution and Erythropoietin injection groups received white noise (100 dB SPL for 3 hours. Cochlear sections were stained by silver staining technique and immunostained by S100 antibody. Results: Histochemical analysis of silver staining sections revealed normal structure and a weak staining in SGNs of healthy control group. However, dark-black cytoplasmic staining, cellular shrinkage and degeneration were detected in saline injection group. On the other hand, a few weakly stained neurons were observed in erythropoietin injection group. S100 staining demonstrated strong reaction in Schwann cells and myelin sheaths of SGNs in healthy control group (p<0.05. In saline solution injection group, Schwann cells showed moderate S100 reaction and other regions of SGNs showed weak reaction (p<0.05. In erythropoietin injection group, strong S100 expression almost similar to the healthy control group was determined, although there was an occasional decrease. Discussion: Erythropoetin may prevent noise induced SGN degeneration via protecting the Schwann cells in rat cochlea.

  8. Comparison of Umbilical Serum Copeptin Relative to Erythropoietin and S100B as Asphyxia Biomarkers at Birth.

    Science.gov (United States)

    Summanen, Milla; Seikku, Laura; Rahkonen, Petri; Stefanovic, Vedran; Teramo, Kari; Andersson, Sture; Kaila, Kai; Rahkonen, Leena

    2017-01-01

    Birth asphyxia, estimated to account for a million neonatal deaths annually, can cause a wide variety of neurodevelopmental impairments. There is a need to develop new, swift methods to identify those neonates who would benefit from neuroprotective treatments such as hypothermia. To examine the utility of cord serum copeptin, a stable byproduct of arginine vasopressin release, as a biomarker of birth asphyxia based on a comparison with 2 biomarkers of hypoxia and brain trauma: erythropoietin and S100B. The study population consisted of 140 singleton, term neonates: 113 controls and 27 with birth asphyxia (2/3 criteria met: umbilical artery pH Copeptin, S100B, and erythropoietin levels in umbilical artery samples were measured by immunoassays. Copeptin correlated in the entire study population more strongly with umbilical artery base excess than S100B and erythropoietin, and only copeptin correlated with arterial pH. Furthermore, only copeptin levels were significantly higher in cases of birth asphyxia, and in vaginally born neonates they were found to increase as a function of labor duration. Copeptin was elevated in neonates born via vacuum extraction, whereas erythropoietin levels showed a slight increase after emergency cesarean section. In this study population, S100B and erythropoietin were not valid biomarkers of birth asphyxia. In contrast, our work suggests that copeptin has high potential to become a routinely used biomarker for acute birth asphyxia and neonatal distress. © 2017 S. Karger AG, Basel.

  9. Guided bone regeneration (GBR) utilizing injectable Vascular Endothelial Growth Factor (VEGF) delivery gel

    Science.gov (United States)

    Kaigler, Darnell; Silva, Eduardo A.; Mooney, David J.

    2013-01-01

    Background Vascularization underlies the success of guided bone regeneration (GBR) procedures. This study evaluated the regenerative potential of GBR in combination with Vascular Endothelial Growth Factor (VEGF) delivery, via an injectable hydrogel system. Methods Critical-sized defects were created in rat calvariae and GBR procedures were performed with a collagen membrane either alone (control), plus bolus delivery of VEGF, or plus application of VEGF releasing hydrogels (VEGF - Alg). Four and eight weeks following treatment, defect sites were evaluated with microcomputed tomographic and histomorphometric analyses for blood vessel and bone formation. Results At four weeks, relative to the control condition, the bolus addition of VEGF did not affect blood vessel density within the defect site; yet, the application of the VEGF+ Alg significantly (pGBR may be a promising strategy for enhancing outcomes of GBR. PMID:22668339

  10. Sanguinarine is a novel VEGF inhibitor involved in the suppression of angiogenesis and cell migration

    Science.gov (United States)

    XU, JIA-YING; MENG, QING-HUI; CHONG, YU; JIAO, YANG; ZHAO, LIN; ROSEN, ELIOT M.; FAN, SAIJUN

    2013-01-01

    Vascular endothelial growth factor (VEGF) is a main angiogenic factor which is known to be upregulated in lung cancer. In the present study, it was demonstrated that sanguinarine, an alkaloid obtained from the bloodroot plant, markedly repressed the VEGF-induced tube formation of human microvascular endothelial cells (HMVECs) and the migration of human A549 lung cancer cells. Furthermore, sanguinarine decreased VEGF secretion and expression in HMVECs and A549 lung cancer cells in a dose- and time-dependent manner. Additionally, sanguinarine inhibited the activation of serum starvation- and hypoxia-induced VEGF promoter activity. Sanguinarine also inhibited the VEGF-mediated Akt and p38 activation, as well as VE-cadherin protein phosphorylation. To the best of our knowledge, this is the first study demonstrating that VEGF inhibition appears to be an important mechanism involved in the antiangiogenic and anti-invasive activities of sanguinarine in lung cancer treatment. PMID:24649171

  11. VEGF secretion during hypoxia depends on free radicals-induced Fyn kinase activity in mast cells

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Roman, Jonathan; Ibarra-Sanchez, Alfredo; Lamas, Monica [Departamento de Farmacobiologia, Centro de Investigacion y de Estudios Avanzados del IPN (Cinvestav, IPN) (Mexico); Gonzalez Espinosa, Claudia, E-mail: cgonzal@cinvestav.mx [Departamento de Farmacobiologia, Centro de Investigacion y de Estudios Avanzados del IPN (Cinvestav, IPN) (Mexico)

    2010-10-15

    Research highlights: {yields} Bone marrow-derived mast cells (BMMCs) secrete functional VEGF but do not degranulate after Cobalt chloride-induced hypoxia. {yields} CoCl{sub 2}-induced VEGF secretion in mast cells occurs by a Ca{sup 2+}-insensitive but brefeldin A and Tetanus toxin-sensitive mechanism. {yields} Trolox and N-acetylcysteine inhibit hypoxia-induced VEGF secretion but only Trolox inhibits Fc{epsilon}RI-dependent anaphylactic degranulation in mast cells. {yields} Src family kinase Fyn activation after free radical production is necessary for hypoxia-induced VEGF secretion in mast cells. -- Abstract: Mast cells (MC) have an important role in pathologic conditions such as asthma and chronic obstructive pulmonary disease (COPD), where hypoxia conduce to deleterious inflammatory response. MC contribute to hypoxia-induced angiogenesis producing factors such as vascular endothelial growth factor (VEGF), but the mechanisms behind the control of hypoxia-induced VEGF secretion in this cell type is poorly understood. We used the hypoxia-mimicking agent cobalt chloride (CoCl{sub 2}) to analyze VEGF secretion in murine bone marrow-derived mast cells (BMMCs). We found that CoCl{sub 2} promotes a sustained production of functional VEGF, able to induce proliferation of endothelial cells in vitro. CoCl{sub 2}-induced VEGF secretion was independent of calcium rise but dependent on tetanus toxin-sensitive vesicle-associated membrane proteins (VAMPs). VEGF exocytosis required free radicals formation and the activation of Src family kinases. Interestingly, an important deficiency on CoCl{sub 2}-induced VEGF secretion was observed in Fyn kinase-deficient BMMCs. Moreover, Fyn kinase was activated by CoCl{sub 2} in WT cells and this activation was prevented by treatment with antioxidants such as Trolox and N-acetylcysteine. Our results show that BMMCs are able to release VEGF under hypoxic conditions through a tetanus toxin-sensitive mechanism, promoted by free radicals

  12. VEGF family members regulate myocardial tubulogenesis and coronary artery formation in the embryo.

    Science.gov (United States)

    Tomanek, Robert J; Ishii, Yasuo; Holifield, Jennifer S; Sjogren, Christina L; Hansen, Heidi K; Mikawa, Takashi

    2006-04-14

    This study tested the hypothesis that coronary tubulogenesis and coronary artery formation require VEGF family members. Quail embryos were injected with soluble vascular endothelial growth factor (VEGF) receptors R1 (Flt-1), R2 (Flk-1), R3 (Flt-4), VEGF-Trap (a chimera of R1 and R2), or neutralizing antibodies to VEGF-A, VEGF-B, or fibroblast growth factor (FGF)-2. Our data document that tubulogenesis is temporally dependent on multiple VEGF family members, because the early stage of tubulogenesis was markedly inhibited by VEGF-Trap and to a lesser extent by soluble VEGFR-1. Some inhibition of tubulogenesis was documented when anti-FGF-2, but not anti-VEGF-A, antibodies were injected at embryonic day 6 (E6). Most importantly, we found that VEGF-Trap injected at either E6 or E7 prevented the formation of coronary arteries. Soluble VEGFR-1 and soluble VEGFR-2 modified the formation of coronary arteries, whereas soluble VEGFR-3 was without effect. Antibodies to VEGF-B, but not VEGF-A, had a strong inhibitory effect on coronary artery development. The absence of coronary artery stems, and thus a functional coronary circulation, in the embryos injected with VEGF-Trap caused an accumulation of erythrocytes in the subepicardium and muscular interventricular septum. Using retroviral cell tagging, we showed that some of the erythrocytes in blood islands and small vascular tubes were progeny of the proepicardium. Thus, another salient finding of this study is the first definitive documentation of proepicardially derived hemangioblasts, which can differentiate into erythrocytes.

  13. VEGF Polymorphisms Related to Higher Serum Levels of Protein Identify Patients with Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Maria Eduarda Lopes Baitello

    2016-01-01

    Full Text Available Hepatocellular carcinoma (HCC is the most common primary neoplasia of the liver. Major risk factors for hepatocellular carcinoma include chronic liver diseases, carcinogenic agents, and genetic alterations as well as vascular endothelial growth factor (VEGF involved in angiogenesis process. The aim of this study was to evaluate the association of VEGF-A (C936T and A1154G with HCC and cirrhosis, in addition to serum levels of VEGF, clinical profile, lifestyle habits, and comorbidities. A total of 346 individuals were studied: 102 with HCC (G1, 117 with cirrhosis (G2, and 127 controls (G3. Polymorphisms were analysed by PCR/RFLP and serum levels of VEGF by ELISA. Alpha error was set at 5%. The wild-type genotype of both polymorphisms prevailed (P>0.05. In G1, 23% of the patients died, with no relation to genetic profile (P>0.05. Increased VEGF level was observed in G1 and G3, related to the mutant allele of VEGF-C936T and VEGF-A1154G, respectively, and compared with the wild-type genotype (P=0.0285; P=0.0284, resp. as well as G1 versus G2 and G3 for VEGF-C936T and G1 versus G2 for VEGF-A1154G (P<0.05 for both. In conclusion, there is a relationship between mutant alleles of VEGF-C936T and VEGF-A1154G polymorphisms and higher VEGF level, making them potential markers for HCC.

  14. Circulating VEGF as a biological marker in patients with rheumatoid arthritis? Preanalytical and biological variability in healthy persons and in patients

    DEFF Research Database (Denmark)

    Hetland, Merete Lund; Christensen, Ib Jarle; Lottenburger, Tine

    2008-01-01

    and contamination of plasma with cellular elements lead to significant increases in VEGF levels, whereas storage for up to 2 years at -80 degrees C or up to 10 freeze/thaw cycles did not affect VEGF levels. Serum VEGF levels were 7-10 fold higher than plasma VEGF levels. Reference intervals for VEGF (plasma: 45 pg...

  15. Erythropoietin receptor in human skeletal muscle and the effects of acute and long-term injections with recombinant human erythropoietin on the skeletal muscle

    DEFF Research Database (Denmark)

    Lundby, Carsten; Hellsten, Ylva; Jensen, Mie B. F.

    2008-01-01

    The presence and potential physiological role of the erythropoietin receptor (Epo-R) were examined in human skeletal muscle. In this study we demonstrate that Epo-R is present in the endothelium, smooth muscle cells, and in fractions of the sarcolemma of skeletal muscle fibers. To study...... the potential effects of Epo in human skeletal muscle, two separate studies were conducted: one to study the acute effects of a single Epo injection on skeletal muscle gene expression and plasma hormones and another to study the effects of long-term (14 wk) Epo treatment on skeletal muscle structure. Subjects....... In conclusion, the Epo-R is present in the vasculature and myocytes in human skeletal muscle, suggesting a role in both cell types. In accordance, a single injection of Epo regulates myoglobin, MRF-4, and transferrin receptor mRNA levels. However, in contrast to our hypothesis, prolonged Epo administration had...

  16. Activating mitochondrial function and haemoglobin expression with EH-201, an inducer of erythropoietin in neuronal cells, reverses memory impairment.

    Science.gov (United States)

    Horng, Lin-Yea; Hsu, Pei-Lun; Chen, Li-Wen; Tseng, Wang-Zou; Hsu, Kai-Tin; Wu, Chia-Ling; Wu, Rong-Tsun

    2015-10-01

    Memory impairment can be progressive in neurodegenerative diseases, and physiological ageing or brain injury, mitochondrial dysfunction and oxidative stress are critical components of these issues. An early clinical study has demonstrated cognitive improvement during erythropoietin treatment in patients with chronic renal failure. As erythropoietin cannot freely cross the blood-brain barrier, we tested EH-201 (2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glucoside, also known as TSG), a low MW inducer of erythropoietin, for its therapeutic effects on memory impairment in models of neurodegenerative diseases, physiological ageing or brain injury. The effects of EH-201 were investigated in astrocytes and PC12 neuronal-like cells. In vivo, we used sleep-deprived (SD) mice as a stress model, amyloid-β (Aβ)-injected mice as a physiological ageing model and kainic acid (KA)-injected mice as a brain damage model to assess the therapeutic effects of EH-201. EH-201 induced expression of erythropoietin, PPAR-γ coactivator 1α (PGC-1α) and haemoglobin in astrocytes and PC12 neuronal-like cells. In vivo, EH-201 treatment restored memory impairment, as assessed by the passive avoidance test, in SD, Aβ and KA mouse models. In the hippocampus of mice given EH-201 in their diet, levels of erythropoietin, PGC-1α and haemoglobin were increased The induction of endogenous erythropoietin in neuronal cells by inducers such as EH-201 might be a therapeutic strategy for memory impairment in neurodegenerative disease, physiological ageing or traumatic brain injury. © 2015 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of The British Pharmacological Society.

  17. The Effect of Depression on Serum VEGF Level in Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    JaeHoon Jung

    2015-01-01

    Full Text Available Objective. Growing evidence suggests that angiogenesis might represent a new pathogenic mechanism involved in the progression of Alzheimer’s disease (AD. Among angiogenic cytokines, vascular endothelial growth factor (VEGF levels in AD patients have been evaluated, but the results are controversial among studies. We investigated serum levels of VEGF in AD patients with depression, AD patients without depression, and the controls, respectively. The aim of this study is to elucidate the relationship between VEGF, depression, and cognitive impairment in AD. Methods. The CDR (Clinical Dementia Rating, MMSE-KC (the Mini-Mental Status Examination-Korean version, and SGDS-K (the Korean version of the Geriatric Depression Scale-Short Form were measured in the subjects. Serum VEGF levels were measured in 24 AD patients with depression, 25 AD patients without depression, and 26 controls, using an enzyme-linked immunosorbent assay kit. Results. Serum VEGF levels in AD patients with depression were significantly higher than AD patients without depression or the control. A correlation was observed between VEGF and scores on SGDS-K, but no correlation was detected between VEGF and MMSE-KC scores. Conclusion. Serum VEGF levels in AD patients with depression were higher than those without depression. Depression might be associated with changes in serum levels of VEGF in AD patients.

  18. Estimation of Immunohistochemical Expression of VEGF in Ductal Carcinomas of the Breast

    DEFF Research Database (Denmark)

    Maae, Else; Nielsen, Martin; Dahl Steffensen, Karina

    2011-01-01

    Vascular endothelial growth factor A (VEGF-A) is a very important growth factor in angiogenesis and holds the potential as both a predictive marker for anti-angiogenic cancer treatment and as a prognostic variable. Consequently, reliable estimation of VEGF expression is crucial. We immunostained...... whole tumor sections for VEGF-A, -B, and VEGFR-1 of invasive ductal carcinomas of the breast and scored the tumors manually with staining intensity as the only parameter and by a combination of qualitative and quantitative information. We also introduce an automated method for analyzing VEGF expression...

  19. Modified VEGF targets the ischemic myocardium and promotes functional recovery after myocardial infarction.

    Science.gov (United States)

    Yang, Yun; Shi, Chunying; Hou, Xianglin; Zhao, Yannan; Chen, Bing; Tan, Bo; Deng, Zongwu; Li, Qingguo; Liu, Jianzhou; Xiao, Zhifeng; Miao, Qi; Dai, Jianwu

    2015-09-10

    Vascular endothelial growth factor (VEGF) promotes angiogenesis and improves cardiac function after myocardial infarction (MI). However, the non-targeted delivery of VEGF decreases its therapeutic efficacy due to an insufficient local concentration in the ischemic myocardium. In this study, we used a specific peptide to modify VEGF and determined that this modified VEGF (IMT-VEGF) localized to the ischemic myocardium through intravenous injection by interacting with cardiac troponin I (cTnI). When IMT-VEGF was used to mediate cardiac repair in a rat model of ischemia-reperfusion (I-R) injury, we observed a decreased scar size, enhanced angiogenesis and improved cardiac function. Moreover, an alternative treatment using the repeated administration of a low-dose IMT-VEGF also promoted angiogenesis and functional recovery. The therapeutic effects of IMT-VEGF were further confirmed in a pig model of MI as the result of the conserved properties of its interacting protein, cTnI. These results suggest a promising therapeutic strategy for MI based on the targeted delivery of IMT-VEGF. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. An increase of VEGF plasma levels is associated with restenosis of drug-eluting stents.

    Science.gov (United States)

    Katsaros, Katharina M; Kastl, Stefan P; Krychtiuk, Konstantin A; Hutter, Randolph; Zorn, Gerlinde; Maurer, Gerald; Huber, Kurt; Wojta, Johann; Christ, Günter; Speidl, Walter S

    2014-06-01

    Drug-eluting stents (DES) reduce late lumen loss compared to bare metal stents but were not able to eradicate in-stent restenosis (ISR) fully. Vascular endothelial growth factor (VEGF) may inhibit late lumen loss through accelerated reendothelialisation, but may also promote neointima formation by proinflammatory effects. The aim of this study was to evaluate whether endogenous plasma levels of VEGF are associated with development of ISR after implantation of DES. We studied 85 patients who were treated with 159 DES. VEGF plasma levels were determined before and 24 hours after PCI. During the eight-month follow-up period, two patients (2.4%) died of cardiovascular causes and 12 patients (14.5% of patients, 7.6% of stents) developed angiographic ISR. Basal VEGF plasma levels were not different in patients with and without ISR at follow-up. In contrast to patients without ISR, VEGF increased significantly upon PCI in patients with ISR (p<0.005). Patients with a decrease of VEGF after PCI had a restenosis rate of 2.4% compared to a restenosis rate of 26.2% in patients with an increase of VEGF after the procedure (p<0.05). This was independent from clinical and angiographic risk factors. Basal plasma levels of VEGF are not associated with the development of ISR. However, an increase of VEGF after PCI is associated with a dramatically increased ISR rate after implantation of DES.

  1. A Biomimic Reconstituted High Density Lipoprotein Nanosystem for Enhanced VEGF Gene Therapy of Myocardial Ischemia

    Directory of Open Access Journals (Sweden)

    Xiaotian Sun

    2015-01-01

    Full Text Available A biomimic reconstituted high density lipoprotein (rHDL based system, rHDL/Stearic-PEI/VEGF complexes, was fabricated as an advanced nanovector for delivering VEGF plasmid. Here, Stearic-PEI was utilized to effectively condense VEGF plasmid and to incorporate the plasmid into rHDL. The rHDL/Stearic-PEI/VEGF complexes with diameter under 100 nm and neutral surface charge demonstrated enhanced stability under the presence of bovine serum albumin. Moreover, in vitro cytotoxicity and transfection assays on H9C2 cells further revealed their superiority, as they displayed lower cytotoxicity with much higher transfection efficiency when compared to PEI 10K/VEGF and Lipos/Stearic-PEI/VEGF complexes. In addition, in vivo investigation on ischemia/reperfusion rat model implied that rHDL/Stearic-PEI/VEGF complexes possessed high transgene capacity and strong therapeutic activity. These findings indicated that rHDL/Stearic-PEI/VEGF complexes could be an ideal gene delivery system for enhanced VEGF gene therapy of myocardial ischemia, which might be a new promising strategy for effective myocardial ischemia treatment.

  2. Exercise-induced capillary growth in human skeletal muscle and the dynamics of VEGF.

    Science.gov (United States)

    Hoier, Birgitte; Hellsten, Ylva

    2014-05-01

    In skeletal muscle, growth of capillaries is an important adaptation to exercise training that secures adequate diffusion capacity for oxygen and nutrients even at high-intensity exercise when increases in muscle blood flow are profound. Mechanical forces present during muscle activity, such as shear stress and passive stretch, lead to cellular signaling, enhanced expression of angiogenic factors, and initiation of capillary growth. The most central angiogenic factor in skeletal muscle capillary growth is VEGF. During muscle contraction, VEGF increases in the muscle interstitium, acts on VEGF receptors on the capillary endothelium, and thereby stimulates angiogenic processes. A primary source of muscle interstitial VEGF during exercise is the skeletal muscle fibers which contain large stores of VEGF within vesicles. We propose that, during muscle activity, these VEGF-containing vesicles are redistributed toward the sarcolemma where the contents are secreted into the extracellular fluid. VEGF mRNA expression is increased primarily after exercise, which allows for a more rapid replenishment of VEGF stores lost through secretion during exercise. Future studies should focus on elucidating mechanisms and regulation of VEGF secretion. © 2014 John Wiley & Sons Ltd.

  3. Cellular and molecular mechanisms involved in the neuroprotective effects of VEGF on motoneurons

    Directory of Open Access Journals (Sweden)

    Jerònia eLladó

    2013-10-01

    Full Text Available Vascular endothelial growth factor (VEGF, originally described as a factor with a regulatory role in vascular growth and development, it is also known for its direct effects on neuronal cells. The discovery in the past decade that transgenic mice expressing reduced levels of VEGF developed late-onset motoneuron pathology, reminiscent of amyotrophic lateral sclerosis (ALS, opened a new field of research on this disease. VEGF has been shown to protect motoneurons from excitotoxic death, which is a relevant mechanism involved in motoneuron degeneration in ALS. Thus, VEGF delays motoneuron degeneration and increases survival in animal models of ALS. VEGF exerts its anti-excitotoxic effects on motoneurons through molecular mechanisms involving the VEGF receptor-2 resulting in the activation of the PI3-K/Akt signaling pathway, upregulation of GluR2 subunit of AMPA receptors, inhibition of p38MAPK and induction of the anti-apoptotic molecule Bcl-2. In addition, VEGF acts on astrocytes to reduce astroglial activation and to induce the release of growth factors. The potential use of VEGF as a therapeutic tool in ALS is counteracted by its vascular effects and by its short effective time frame. More studies are needed to assess the optimal isoform, route of administration and time frame for using VEGF in the treatment of ALS.

  4. Management of anemia in patients undergoing curative radiotherapy. Erythropoietin, transfusions, or better nothing?

    Energy Technology Data Exchange (ETDEWEB)

    Dunst, J. [Dept. of Radiotherapy, Martin Luther Univ. Halle-Wittenberg, Halle (Germany)

    2004-11-01

    Background and results: anemia is a well-known risk factor for decreased local control and survival in patients undergoing curative radiotherapy. There is clear evidence from recent clinical investigations that anemia is an independent risk factor and hemoglobin (Hb) levels during radiotherapy are important (and not pretreatment Hb levels). The most likely explanation for the prognostic impact is the association with tumor hypoxia. An ''optimal'' Hb range with regard to tumor oxygenation seems to exist, and Hb levels < 11 g/dl and > {proportional_to}15 g/dl impair tumor oxygenation but have (over a broader range) no significant impact on normal tissue oxygenation. There is some evidence from retrospective and prospective studies that the response to radiotherapy and the prognosis, especially in cervical cancers, might be improved if the Hb levels during radiotherapy can be maintained in the optimal range, either by transfusions or by erythropoietin. The effect of any antianemic therapy should be analyzed according to whether or not treatment was successful with regard to achieving optimal Hb levels during irradiation. Erythropoietin is probably more effective in steadily increasing and stabilizing Hb levels, but bears the risk of overcorrection of Hb levels. The clinical relevance of erythropoietin receptors on tumor cells remains questionable. Conclusions: treatment of anemia with the objective of improving local control and survival in radiotherapy patients is probably more difficult and sophisticated than coping with symptoms of anemia or improving quality of life. Nevertheless, the potential of antianemic treatment is high on the basis of experimental and clinical data, and further clinical trials are warranted. (orig.)

  5. Erythropoietin modulates neural and cognitive processing of emotional information in biomarker models of antidepressant drug action in depressed patients

    DEFF Research Database (Denmark)

    Miskowiak, Kamilla W; Favaron, Elisa; Hafizi, Sepehr

    2010-01-01

    Erythropoietin (Epo) has neuroprotective and neurotrophic effects, and may be a novel therapeutic agent in the treatment of psychiatric disorders. We have demonstrated antidepressant-like effects of Epo on the neural and cognitive processing of facial expressions in healthy volunteers. The curren...... study investigates the effects of Epo on the neural and cognitive response to emotional facial expressions in depressed patients.......Erythropoietin (Epo) has neuroprotective and neurotrophic effects, and may be a novel therapeutic agent in the treatment of psychiatric disorders. We have demonstrated antidepressant-like effects of Epo on the neural and cognitive processing of facial expressions in healthy volunteers. The current...

  6. SFRP2 Is Associated with Increased Adiposity and VEGF Expression.

    Science.gov (United States)

    Crowley, Rachel K; O'Reilly, Michael W; Bujalska, Iwona J; Hassan-Smith, Zaki K; Hazlehurst, Jonathan M; Foucault, Danielle R; Stewart, Paul M; Tomlinson, Jeremy W

    The aim of this study was to assess depot-specific expression and secretion of secreted frizzled-related protein 2 (sFRP2) by adipose tissue and its effect on adipocyte biology. We measured serum sFRP2 concentrations in 106 patients in vivo to explore its relationship to fat mass, glycaemia and insulin resistance. Expression of sFRP2 in mouse and human tissues was assessed using polymerase chain reaction and Western blot. Western blot confirmed secretion of sFRP2 by adipose tissue into cell culture medium. Effects of recombinant sFRP2 on lipogenesis and preadipocyte proliferation were measured. Preadipocyte expression of the angiogenic genes vascular endothelial growth factor (VEGF) and nuclear factor of activated T-cells 3 (NFATC3) was measured after recombinant sFRP2 exposure. Complementary clinical studies correlating human serum sFRP2 with age, gender, adiposity and insulin secretion were also performed. sFRP2 messenger RNA (mRNA) was expressed in mouse and human adipose tissue. In humans, sFRP2 mRNA expression was 4.2-fold higher in omental than subcutaneous adipose. Omental adipose tissue secreted 63% more sFRP2 protein than subcutaneous. Treatment with recombinant sFRP2 did not impact on lipogenesis or preadipocyte proliferation but was associated with increased VEGF mRNA expression. In human subjects, circulating insulin levels positively correlated with serum sFRP2, and levels were higher in patients with abnormal glucose tolerance (34.2ng/ml) compared to controls (29.5ng/ml). A positive correlation between sFRP2 and BMI was also observed. Circulating sFRP2 is associated with adipose tissue mass and has a potential role to drive adipose angiogenesis through enhanced VEGF expression.

  7. Corneal avascularity is due to soluble VEGF receptor-1.

    Science.gov (United States)

    Ambati, Balamurali K; Nozaki, Miho; Singh, Nirbhai; Takeda, Atsunobu; Jani, Pooja D; Suthar, Tushar; Albuquerque, Romulo J C; Richter, Elizabeth; Sakurai, Eiji; Newcomb, Michael T; Kleinman, Mark E; Caldwell, Ruth B; Lin, Qing; Ogura, Yuichiro; Orecchia, Angela; Samuelson, Don A; Agnew, Dalen W; St Leger, Judy; Green, W Richard; Mahasreshti, Parameshwar J; Curiel, David T; Kwan, Donna; Marsh, Helene; Ikeda, Sakae; Leiper, Lucy J; Collinson, J Martin; Bogdanovich, Sasha; Khurana, Tejvir S; Shibuya, Masabumi; Baldwin, Megan E; Ferrara, Napoleone; Gerber, Hans-Peter; De Falco, Sandro; Witta, Jassir; Baffi, Judit Z; Raisler, Brian J; Ambati, Jayakrishna

    2006-10-26

    Corneal avascularity-the absence of blood vessels in the cornea-is required for optical clarity and optimal vision, and has led to the cornea being widely used for validating pro- and anti-angiogenic therapeutic strategies for many disorders. But the molecular underpinnings of the avascular phenotype have until now remained obscure and are all the more remarkable given the presence in the cornea of vascular endothelial growth factor (VEGF)-A, a potent stimulator of angiogenesis, and the proximity of the cornea to vascularized tissues. Here we show that the cornea expresses soluble VEGF receptor-1 (sVEGFR-1; also known as sflt-1) and that suppression of this endogenous VEGF-A trap by neutralizing antibodies, RNA interference or Cre-lox-mediated gene disruption abolishes corneal avascularity in mice. The spontaneously vascularized corneas of corn1 and Pax6+/- mice and Pax6+/- patients with aniridia are deficient in sflt-1, and recombinant sflt-1 administration restores corneal avascularity in corn1 and Pax6+/- mice. Manatees, the only known creatures uniformly to have vascularized corneas, do not express sflt-1, whereas the avascular corneas of dugongs, also members of the order Sirenia, elephants, the closest extant terrestrial phylogenetic relatives of manatees, and other marine mammals (dolphins and whales) contain sflt-1, indicating that it has a crucial, evolutionarily conserved role. The recognition that sflt-1 is essential for preserving the avascular ambit of the cornea can rationally guide its use as a platform for angiogenic modulators, supports its use in treating neovascular diseases, and might provide insight into the immunological privilege of the cornea.

  8. Combined therapy with amifostine plus erythropoietin for the treatment of myelodysplastic syndromes

    DEFF Research Database (Denmark)

    Musto, Pellegrino; Santini, Valeria; Balestri, Francesca

    2002-01-01

    Twelve patients with myelodysplasia were treated with amifostine plus recombinant human erythropoietin (rHuEpo) for 6 weeks. A complete erythroid response was obtained in 2/12(16.6%) and a partial response in 4/12 (33.3%). Two of 8 patients with a platelet count 9)/L had a complete...... response, as did 3/9 with a neutrophil count 9)/L.Compared to rHuEpo or amifostine used as single agents, their combination did not offer substantial advantages....

  9. Pathogenesis and therapy of anemia in oncohemathology patients with recombinant erythropoietin agents (review

    Directory of Open Access Journals (Sweden)

    N. A. Romanenko

    2012-01-01

    Full Text Available The article presents a literature review on the mechanisms of anemia in patients with hematologic malignancies and a classification of chronic anemia and methods of its correction. It describes in detail the mechanism of action, indications and side effects of rembinant erythropoietin (rEPO. It gives anemia treatment algorithms with rEPO in patients with chronic blood malignancies. The analysis of rEPO efficacy is shown in anemia treatment in patients with various types of cancer. It presents the recommendations of ASCO/ASH for the use of rEPO in various patients categories.

  10. Pathogenesis and therapy of anemia in oncohemathology patients with recombinant erythropoietin agents (review

    Directory of Open Access Journals (Sweden)

    N. A. Romanenko

    2014-07-01

    Full Text Available The article presents a literature review on the mechanisms of anemia in patients with hematologic malignancies and a classification of chronic anemia and methods of its correction. It describes in detail the mechanism of action, indications and side effects of rembinant erythropoietin (rEPO. It gives anemia treatment algorithms with rEPO in patients with chronic blood malignancies. The analysis of rEPO efficacy is shown in anemia treatment in patients with various types of cancer. It presents the recommendations of ASCO/ASH for the use of rEPO in various patients categories.

  11. Potent small molecule Hedgehog agonists induce VEGF expression in vitro.

    Science.gov (United States)

    Seifert, Katrin; Büttner, Anita; Rigol, Stephan; Eilert, Nicole; Wandel, Elke; Giannis, Athanassios

    2012-11-01

    Here, we describe the synthesis, SAR studies as well as biological investigations of the known Hedgehog signaling agonist SAG and a small library of its analogues. The SAG and its derivatives were analyzed for their potency to activate the expression of the Hh target gene Gli1 in a reporter gene assay. By analyzing SAR important molecular descriptors for Gli1 activation have been identified. SAG as well as compound 10c proven to be potent activators of VEGF expression in cultivated dermal fibroblasts. Importantly and in contrast to SAG, derivative 10c displayed no toxicity in concentrations up to 250 μm. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Delineating multiple functions of VEGF-A in the adult brain.

    Science.gov (United States)

    Licht, Tamar; Keshet, Eli

    2013-05-01

    Vascular endothelial growth factor-A (abbreviated throughout this review as VEGF) is mostly known for its angiogenic activity, for its activity as a vascular permeability factor, and for its vascular survival activity [1]. There is a growing body of evidence, however, that VEGF fulfills additional less 'traditional' functions in multiple organs, both during development, as well as homeostatic functions in fully developed organs. This review focuses on the multiple roles of VEGF in the adult brain and is less concerned with the roles played by VEGF during brain development, functions described elsewhere in this review series. Most functions of VEGF that are essential for proper brain development are, in fact, dispensable in the adult brain as was clearly demonstrated using a conditional brain-specific VEGF loss-of-function (LOF) approach. Thus, in contrast to VEGF LOF in the developing brain, a process which is detrimental for the growth and survival of blood vessels and leads to massive neuronal apoptosis [2-4], continued signaling by VEGF in the mature brain is no longer required for maintaining already established cerebral vasculature and its inhibition does not cause appreciable vessel regression, hypoxia or apoptosis [4-7]. Yet, VEGF continues to be expressed in the adult brain in a constitutive manner. Moreover, VEGF is expressed in the adult brain in a region-specific manner and in distinctive spatial patterns incompatible with an angiogenic role (see below), strongly suggesting angiogenesis-independent and possibly also perfusion-independent functions. Here we review current knowledge on some of these 'non-traditional', often unexpected homeostatic VEGF functions, including those unrelated to its effects on the brain vasculature. These effects could be mediated directly (on non-vascular cells expressing cognate VEGF receptors) or indirectly (via the endothelium). Experimental approaches aimed at distinguishing between these possibilities for each particular

  13. Detection of VEGF-A(xxx)b isoforms in human tissues.

    Science.gov (United States)

    Bates, David O; Mavrou, Athina; Qiu, Yan; Carter, James G; Hamdollah-Zadeh, Maryam; Barratt, Shaney; Gammons, Melissa V; Millar, Ann B; Salmon, Andrew H J; Oltean, Sebastian; Harper, Steven J

    2013-01-01

    Vascular Endothelial Growth Factor-A (VEGF-A) can be generated as multiple isoforms by alternative splicing. Two families of isoforms have been described in humans, pro-angiogenic isoforms typified by VEGF-A165a, and anti-angiogenic isoforms typified by VEGF-A165b. The practical determination of expression levels of alternative isoforms of the same gene may be complicated by experimental protocols that favour one isoform over another, and the use of specific positive and negative controls is essential for the interpretation of findings on expression of the isoforms. Here we address some of the difficulties in experimental design when investigating alternative splicing of VEGF isoforms, and discuss the use of appropriate control paradigms. We demonstrate why use of specific control experiments can prevent assumptions that VEGF-A165b is not present, when in fact it is. We reiterate, and confirm previously published experimental design protocols that demonstrate the importance of using positive controls. These include using known target sequences to show that the experimental conditions are suitable for PCR amplification of VEGF-A165b mRNA for both q-PCR and RT-PCR and to ensure that mispriming does not occur. We also provide evidence that demonstrates that detection of VEGF-A165b protein in mice needs to be tightly controlled to prevent detection of mouse IgG by a secondary antibody. We also show that human VEGF165b protein can be immunoprecipitated from cultured human cells and that immunoprecipitating VEGF-A results in protein that is detected by VEGF-A165b antibody. These findings support the conclusion that more information on the biology of VEGF-A165b isoforms is required, and confirm the importance of the experimental design in such investigations, including the use of specific positive and negative controls.

  14. Evaluation of anticancer peptide VEGF111b secretion in HEK293 human cells

    Directory of Open Access Journals (Sweden)

    Morteza Sadeghi

    2017-04-01

    Full Text Available Background: VEGF111b is a new isoform of vascular endothelial growth factor (VEGF recently considered as a new anticancer drug. The aim of this study was to evaluate the VEGF111b secretion from HEK293 cell wall in order to commercial production of this recombinant factor. Materials and Methods: After the design of VEGF111b sequence using OLIGO software and NCBI gene bank data, it was cloned into the pBUD.cE4.1 vector. The pBUD.VEGF111b recombinant vector was transfected into HEK293 cells using lipofectamine kit. Forty-eight hours after the transfection the production of VEGF111b was estimated by Western blotting and Human anti VEGF antibody. The VEGF111b secretion into cell culture and cell lysate extract was measured using ELISA. Results: The correct cloning of VEGF111b into pBUD.cE4.1vector was confirmed using enzymatic digestion and gel electrophoresis. The observed production of recombinant peptide in HEK293 was confirmed with 12KDa band in cell lysate extract of Western blotting. The ELISA results at 450 nanometer absorbance for cell culture media and cell lysate extract were 19.20±2.81 pg/ml and 32.87±7.42 pg/ml, respectively. However, no VEGF111b expression was observed in negative controls. Conclusion: The findings of this study indicate the powerful ability of transformation and secretion of VEGF111b from HEK293 cell wall to cell culture media with no breaking and proteolytic digestion. It seems that the commercial production and purification of this therapeutic peptide from HEK293 cell culture would be possible with high efficiency.

  15. Epithelial membrane protein 2 controls VEGF expression in ARPE-19 cells.

    Science.gov (United States)

    Morales, Shawn A; Telander, David G; Leon, Deanna; Forward, Krisztina; Braun, Jonathan; Wadehra, Madhuri; Gordon, Lynn K

    2013-03-28

    VEGF production by RPE cells has been shown to be important in regulating aberrant angiogenesis in the retina, which is responsible for multiple types of ocular pathology. EMP2 is highly expressed in the RPE and has been shown to regulate FAK activation, which is implicated in VEGF expression in other cell lines. The purpose of this study was to determine whether EMP2 regulates VEGF expression in the RPE cell line, ARPE-19. ARPE-19 cells were engineered to overexpress EMP2. EMP2 siRNA was used to decrease EMP2 expression. The small molecule inhibitor PP2 was used to inhibit FAK activation. VEGF levels were measured by Western blot and ELISA. Functional differences in secreted VEGF were assayed using HUVEC migration. VEGF expression levels correlated with levels of EMP2. An increase of VEGF by 150% was observed in EMP2 overexpressing cells as compared with ARPE-19 cells. Concordantly, EMP2 knockdown resulted in a 57% decrease in VEGF expression. HUVEC migration (P = 0.01) and vessel tube formation (P < 0.01) were significantly increased when exposed to cell culture supernatants from EMP2 overexpressing cells. This study establishes a novel connection between EMP2 and VEGF and may reflect either a direct effect through the tetraspan web or an indirect change through FAK activation. This connection is functionally significant. In addition to the direct use of anti-VEGF antibodies, modulation of EMP2 with impact on VEGF is potentially a distinct therapeutic target for the treatment of neovascularization associated with retinal diseases that involve pathologic angiogenesis.

  16. Molecular Analysis of Vascular Endothelial Growth Factor (VEGF) Receptors in EUS-guided Samples Obtained from Patients with Pancreatic Adenocarcinoma.

    Science.gov (United States)

    Costache, Madalin Ionut; Iordache, Sevastita; Costache, Cornelia Alexandra; Dragos, Ene; Dragos, Alexandru; Saftoiu, Adrian

    2017-03-01

    Vascular endothelial growth factor (VEGF) and its receptors (VEGF-R1 and VEGF-R2) are the most important angiogenesis stimulating factors in pancreatic cancer. This study aims to assess VEGF-R1 and VEGF-R2 gene expression in EUS-FNA samples and identify prognostic markers in pancreatic adenocarcinoma. This was a retrospective study of prospectively collected data of 88 consecutive patients, with clinical and imaging suspicion of pancreatic neoplasms, based on samples obtained through endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). EUS had an accuracy of 93.2% for the diagnosis of pancreatic cancer. Based on real-time qPCR analysis, VEGF-R1 and VEGF-R2 expressions were present in 90% and 65% of the analysed malignant samples, respectively; 89% of the patients died during the study, with a median survival rate of only 9 months. The survival was correlated with the initial stage and with the presence of VEGF-R1 and VEGF-R2 gene expression. We found that there are significant correlations between death/survival and T stage, N stage, resectability status, VEGF-R1, VEGF-R2 and VEGF-R1/VEGF-R2 coexpression. Using a Cox model regression our study demonstrates that VEGF-R1/VEGF-R2 coexpression might be considered as a poor prognostic factor in pancreatic cancer. EUS is a very effective technique for the diagnosis and staging of pancreatic adenocarcinoma in patients with clinical and imaging suspicion of pancreatic neoplasm, with an accuracy of 93.2%. Furthermore, the role of molecular analysis of EUS-guided FNA samples was established by the assessment of VEGF-R1, VEGF-R2 gene expression, which might be considered prognostic markers in pancreatic cancer.

  17. [Macular Edema in Uveitis - Steroids or VEGF Inhibitors?

    Science.gov (United States)

    Heinz, Carsten; Heiligenhaus, Arnd

    2017-06-09

    Macular edema in uveitis patients is certainly the most frequent complication leading to a permanent and irreversible reduction in vision during the course of the disease. Thanks to optical coherence tomography (OCT) technology and fluorescein angiography (FAG), significantly more macular edemas are detected. Macular edema can be found in various uveitis varieties and can show different clinical patterns. All macular edema should be treated. Macular edema with active inflammation usually reacts very well to general uveitis treatment. In the case of eyes without visible inflammation, however, the response to such therapy is usually less effective. According to the latest treatment recommendations, dexamethasone implants should be used as the first intravitreal therapy. Vascular endothelial growth factor inhibitors (VEGF inhibitors) are second-line treatment regimens. The choice of therapy is, therefore, primarily based on the degree of inflammation and the individual complications, such as glaucoma, lens situation or previous increase in IOP after steroid administration. These individual complications may allow using VEGF inhibitors as first line treatment. An improvement in the macular edema can be achieved with both groups of active substances. Georg Thieme Verlag KG Stuttgart · New York.

  18. Comparative structural study of N-linked oligosaccharides of urinary and recombinant erythropoietins

    Energy Technology Data Exchange (ETDEWEB)

    Tsuda, E.; Goto, M.; Murakami, A.; Akia, K.; Ueda, M.; Kawanishi, G.; Takahashi, N.; Sasaki, R.; Chiba, H.; Ishihara, H.; Mori, M.

    1988-07-26

    The structures of the N-linked oligosaccharides of the urinary erythropoietin (u-EPOI) purified from urine of aplastic anemic patients were analyzed and compared with those for recombinant erythropoietin (r-EPO) prepared with baby hamster kidney (BHK) cells. Asparagine-linked neutral oligosaccharides were released from each EPO protein by N-oligosaccharide glycopeptidase (almond) digestion. The reducing ends of the oligosaccharide chains thus obtained were aminated with a fluorescent reagent, 2-aminopyridine, and the mixture of pyridylamino derivatives of the oligosaccharides was separated by high-performance liquid chromatography (HPLC) on an ODS silica column. More than 8 and 13 kinds of oligosaccharide fractions for u-EPO and r-EPO (BHK), respectively, were completely separated by the one-step HPLC procedure. The structure of each oligosaccharide thus isolated was analyzed by a combination of sequential exoglycosidase digestion and another kind of HPLC with an amide-silica column. Furthermore, high-resolution proton nuclear magnetic resonance (/sup 1/H NMR) spectroscopy and methylation analyses were carried out in the case of r-EPO (BHK).

  19. Erythropoietin augments the cytokine response to acute endotoxin-induced inflammation in humans

    DEFF Research Database (Denmark)

    Hojman, Pernille; Taudorf, Sarah; Lundby, Carsten

    2009-01-01

    Recent studies have shown that erythropoietin (EPO) offers protection against ischemia, hemorrhagic shock and systemic inflammation in many tissues and it has been suggested that EPO has anti-inflammatory effects. With the aim of investigating the potential acute anti-inflammatory effects of EPO ...... with endotoxin, the levels of TNF-alpha and IL-6 were enhanced by 5- and 40-fold, respectively, whereas the endotoxin-induced increase in IL-10 response was not influenced by EPO. In contrast to our hypothesis, we find that EPO augments the acute inflammatory effect.......Recent studies have shown that erythropoietin (EPO) offers protection against ischemia, hemorrhagic shock and systemic inflammation in many tissues and it has been suggested that EPO has anti-inflammatory effects. With the aim of investigating the potential acute anti-inflammatory effects of EPO...... in a human in vivo model of acute systemic low-grade inflammation, we measured circulating inflammatory mediators after intravenous administration of Escherichia coli endotoxin (LPS) bolus injection (0.1 ng/kg of body weight) in young healthy male subjects. The subjects were divided into three groups...

  20. Oxpentifylline versus placebo in the treatment of erythropoietin-resistant anaemia: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Fassett Robert G

    2008-08-01

    Full Text Available Abstract Background The main hypothesis of this study is that Oxpentifylline administration will effectively treat erythropoietin- or darbepoietin-resistant anaemia in chronic kidney disease patients. Methods/design Inclusion criteria are adult patients with stage 4 or 5 chronic kidney disease (including dialysis patients with significant anaemia (haemoglobin ≤ 110 g/L for at least 3 months for which there is no clear identifiable cause and that is unresponsive to large doses of either erythropoietin (≥ 200 IU/kg/week or darbepoetin (≥ 1 μg/kg/week. Patients will be randomized 1:1 to receive either placebo (1 tablet daily or oxpentifylline (400 mg daily per os for a period of 4 months. During this 4 month study period, haemoglobin measurements will be performed monthly. The primary outcome measure will be the difference in haemoglobin level between the 2 groups at the end of the 4 month study period, adjusted for baseline values. Secondary outcome measures will include erythropoiesis stimulating agent dosage, Key's index (erythropoiesis stimulating agent dosage divided by haemoglobin concentration, and blood transfusion requirement. Discussion This investigator-initiated multicentre study has been designed to provide evidence to help nephrologists and their chronic kidney disease patients determine whether oxpentifylline represents a safe and effective strategy for treating erythropoiesis stimulating agent resistance in chronic kidney disease. Trial Registration Australian New Zealand Clinical Trials Registry Number ACTRN12608000199314.

  1. Erythropoietin combined with liposomal amphotericin b improves outcome during disseminated aspergillosis in mice

    Directory of Open Access Journals (Sweden)

    nathalie erousseau

    2014-10-01

    Full Text Available Disseminated aspergillosis is responsible for a high mortality rate despite the use of antifungal drugs. Adjuvant therapies are urgently needed to improve the outcome. The aim of this study was to demonstrate that the cytoprotective effect of erythropoietin combined to amphotericin b can reduce the mortality rate in a murine model of disseminated aspergillosis. After infection with Aspergillus fumigatus, neutropenic mice were randomized to receive vehicle or 7,5 mg/Kg of Liposomal Amphotericin B (LAmB or 7,5 mg/Kg of LAmB combined with 1000 IU/Kg of EPO (16 mice per group. Aspergillus galactomannan and organ cultures were performed to evaluate fungal burden at day 5. Cumulative long-term survival was analyzed at day 12 post-infection according to the Kaplan-Meier method. At day 5, fungal burden was similar between non-treated and treated groups. At day 12, mortality rates were 75 %, 62.5 % and 31 % in control group, LAmB group and EPO/LAmB group, respectively. We observed a significant decreased in mortality using EPO/LAmB combination compared to control group (p < 0.01. LAmB single treatment did not improve the survival rate compared to control group (p = 0.155.Our results provided the first evidence that erythropoietin improved the outcome of mice presenting disseminated aspergillosis when combined with amphotericin b.

  2. VEGF-C Is a Thyroid Marker of Malignancy Superior to VEGF-A in the Differential Diagnostics of Thyroid Lesions.

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    Kosma Woliński

    Full Text Available Thyroid nodular goiter is one of the most common medical conditions affecting even over a half of adult population. The risk of malignancy is rather small but noticeable-estimated by numerous studies to be about 3-10%. The definite differentiation between benign and malignant ones is a vital issue in endocrine practice. The aim of the current study was to assess the expression of vascular endothelial growth factor A (VEGF-A and VEGF-C on the mRNA level in FNAB washouts in case of benign and malignant thyroid nodules and to evaluate the diagnostic value of these markers of malignancy.Patients undergoing fine-needle aspiration biopsy (FNAB in our department between January 2013 and May 2014 were included. In case of all patients who gave the written consent, after ultrasonography (US and fine-needle aspiration biopsy (FNAB performed as routine medical procedure the needle was flushed with RNA Later solution, the washouts were frozen in -80 Celsius degrees. Expression of VEGF-A and VEGF-C and GADPH (reference gene was assessed in washouts on the mRNA level using the real-time PCR technique. Probes of patients who underwent subsequent thyroidectomy and were diagnosed with differentiated thyroid cancer (DTC; proved by post-surgical histopathology were analyzed. Similar number of patients with benign cytology were randomly selected to be a control group.Thirty one DTCs and 28 benign thyroid lesions were analyzed. Expression of VEGF-A was insignificantly higher in patients with DTCs (p = 0.13. Expression of VEGF-C was significantly higher in patients with DTC. The relative expression of VEGF-C (in comparison with GAPDH was 0.0049 for DTCs and 0.00070 for benign lesions, medians - 0.0036 and 0.000024 respectively (p<0.0001.Measurement of expression VEGF-C on the mRNA level in washouts from FNAB is more useful than more commonly investigated VEGF-A. Measurement of VEGF-C in FNAB washouts do not allow for fully reliable differentiation of benign and

  3. A compartment model of VEGF distribution in humans in the presence of soluble VEGF receptor-1 acting as a ligand trap.

    Directory of Open Access Journals (Sweden)

    Florence T H Wu

    Full Text Available Vascular endothelial growth factor (VEGF, through its activation of cell surface receptor tyrosine kinases including VEGFR1 and VEGFR2, is a vital regulator of stimulatory and inhibitory processes that keep angiogenesis--new capillary growth from existing microvasculature--at a dynamic balance in normal physiology. Soluble VEGF receptor-1 (sVEGFR1--a naturally-occurring truncated version of VEGFR1 lacking the transmembrane and intracellular signaling domains--has been postulated to exert inhibitory effects on angiogenic signaling via two mechanisms: direct sequestration of angiogenic ligands such as VEGF; or dominant-negative heterodimerization with surface VEGFRs. In pre-clinical studies, sVEGFR1 gene and protein therapy have demonstrated efficacy in inhibiting tumor angiogenesis; while in clinical studies, sVEGFR1 has shown utility as a diagnostic or prognostic marker in a widening array of angiogenesis-dependent diseases. Here we developed a novel computational multi-tissue model for recapitulating the dynamic systemic distributions of VEGF and sVEGFR1. Model features included: physiologically-based multi-scale compartmentalization of the human body; inter-compartmental macromolecular biotransport processes (vascular permeability, lymphatic drainage; and molecularly-detailed binding interactions between the ligand isoforms VEGF(121 and VEGF(165, signaling receptors VEGFR1 and VEGFR2, non-signaling co-receptor neuropilin-1 (NRP1, as well as sVEGFR1. The model was parameterized to represent a healthy human subject, whereupon we investigated the effects of sVEGFR1 on the distribution and activation of VEGF ligands and receptors. We assessed the healthy baseline stability of circulating VEGF and sVEGFR1 levels in plasma, as well as their reliability in indicating tissue-level angiogenic signaling potential. Unexpectedly, simulated results showed that sVEGFR1 - acting as a diffusible VEGF sink alone, i.e., without sVEGFR1-VEGFR heterodimerization

  4. PGC-1alpha mediates exercise-induced skeletal muscle VEGF expression in mice

    DEFF Research Database (Denmark)

    Leick, Lotte; Hellsten, Ylva; Fentz, Joachim

    2009-01-01

    The aim of the present study was to test the hypothesis that PGC-1alpha is required for exercise-induced VEGF expression in both young and old mice and that AMPK activation leads to increased VEGF expression through a PGC-1alpha-dependent mechanism. Whole body PGC-1alpha knockout (KO) and litterm...

  5. Increased VEGF-A promotes multiple distinct aging diseases of the eye through shared pathomechanisms.

    Science.gov (United States)

    Marneros, Alexander G

    2016-03-01

    While increased VEGF-A has been associated with neovascular age-related macular degeneration (AMD), it is not known whether VEGF-A may also promote other age-related eye diseases. Here, we show that an increase in VEGF-A is sufficient to cause multiple distinct common aging diseases of the eye, including cataracts and both neovascular and non-exudative AMD-like pathologies. In the lens, increased VEGF-A induces age-related opacifications that are associated with ERK hyperactivation, increased oxidative damage, and higher expression of the NLRP3 inflammasome effector cytokine IL-1β. Similarly, increased VEGF-A induces oxidative stress and IL-1β expression also in the retinal pigment epithelium (RPE). Targeting NLRP3 inflammasome components or Il1r1 strongly inhibited not only VEGF-A-induced cataract formation, but also both neovascular and non-exudative AMD-like pathologies. Moreover, increased VEGF-A expression specifically in the RPE was sufficient to cause choroidal neovascularization (CNV) as in neovascular AMD, which could be inhibited by RPE-specific inactivation of Flk1, while Tlr2 inactivation strongly reduced CNV. These findings suggest a shared pathogenic role of VEGF-A-induced and NLRP3 inflammasome-mediated IL-1β activation for multiple distinct ocular aging diseases. © 2016 The Author. Published under the terms of the CC BY 4.0 license.

  6. The VEGF system and tie-2 are spatio-temporal expressed during tayassu placentation

    DEFF Research Database (Denmark)

    Miglino, M.A.; Santos, T.C.; Papa, P.C.

    for immunhistochemistry using polyclonal antibodies against VEGF, VEGFR-1, VEGFR-2 and Tie-2. Results: In the present study the VEGF-system exhibited intense staining in the uterine epithelium, uterine glandular epithelium and trophoblast. The endothelial cells and smooth muscle cells of the vessels in the maternal...

  7. Identification and in vitro characterization of phage-displayed VHHs targeting VEGF

    DEFF Research Database (Denmark)

    Farajpour, Zahra; Rahbarizadeh, Fatemeh; Kazemi, Bahram

    2014-01-01

    Vascular endothelial growth factor (VEGF) is a potential target for cancer treatment because of its role in angiogenesis and its overexpression in most human cancers. Currently, anti-VEGF antibodies have been shown to be promising tools for therapeutic applications. However, large size, poor tumo...

  8. Synthesis of the human VEGF 165 gene based on overlap PCR and ...

    African Journals Online (AJOL)

    Synthesis of the human VEGF165 gene based on overlap PCR and recombinant expression in stable transfected CHO cells. J Zhang, T Wang, B Yang, Y Lin, Z Li. Abstract. Vascular endothelial growth factors (VEGFs) are a member of a family of structurally related proteins that mediate angiogenesis, and vascular ...

  9. Anti-VEGF agents in metastatic colorectal cancer (mCRC: are they all alike?

    Directory of Open Access Journals (Sweden)

    Saif MW

    2013-06-01

    Full Text Available Muhammad Wasif Saif GI Oncology Program, Tufts University School of Medicine, Boston, MA, USA Abstract: Bevacizumab is a monoclonal antibody that binds and neutralizes vascular endothelial growth factor (VEGF-A, a key player in the angiogenesis pathway. Despite benefits of bevacizumab in cancer therapy, it is clear that the VEGF pathway is complex, involving multiple isoforms, receptors, and alternative ligands such as VEGF-B, and placental growth factor, which could enable escape from VEGF-A-targeted angiogenesis inhibition. Recently developed therapies have targeted other ligands in the VEGF pathway (eg, aflibercept, known as ziv-aflibercept in the United States, VEGF receptors (eg, ramucirumab, and their tyrosine kinase signaling (ie, tyrosine kinase inhibitors. The goal of the current review was to identify comparative preclinical data for the currently available VEGF-targeted therapies. Sources were compiled using PubMed searches (2007 to 2012, using search terms including, but not limited to: “bevacizumab,” “aflibercept,” “ramucirumab,” and “IMC-18F1.” Two preclinical studies were identified that compared bevacizumab and the newer agent, aflibercept. These studies identified some important differences in binding and pharmacodynamic activity, although the potential clinical relevance of these findings is not known. Newer antiangiogenesis therapies should help further expand treatment options for colorectal and other cancers. Comparative preclinical data on these agents is currently lacking. Keywords: aflibercept, antiangiogenesis, metastatic colorectal cancer (mCRC, tyrosine kinase inhibitor (TKI, vascular endothelial growth factor (VEGF

  10. Differential actions of VEGF-A isoforms on perichondrial angiogenesis during endochondral bone formation.

    Science.gov (United States)

    Takimoto, Aki; Nishizaki, Yuriko; Hiraki, Yuji; Shukunami, Chisa

    2009-08-15

    During endochondral bone formation, vascular invasion initiates the replacement of avascular cartilage by bone. We demonstrate herein that the cartilage-specific overexpression of VEGF-A(164) in mice results in the hypervascularization of soft connective tissues away from cartilage. Unexpectedly, perichondrial tissue remained avascular in addition to cartilage. Hypervascularization of tissues similarly occurred when various VEGF-A isoforms were overexpressed in the chick forelimb, but also in this case perichondrial tissue and cartilage were completely devoid of vasculature. However, following bony collar formation, anti-angiogenic properties in perichondrial tissue were lost and perichondrial angiogenesis was accelerated by VEGF-A(146), VEGF-A(166), or VEGF-A(190). Once the perichondrium was vascularized, osteoclast precursors were recruited from the circulation and the induction of MMP9 and MMP13 can be observed in parallel with the activation of TGF-beta signaling. Neither perichondrial angiogenesis nor the subsequent cartilage vascularization was found to be accelerated by the non-heparin-binding VEGF-A(122) or by the VEGF-A(166)DeltaE(162)-R(166) mutant lacking a neuropilin-binding motif. Hence, perichondrial angiogenesis is a prerequisite for subsequent cartilage vascularization and is differentially regulated by VEGF-A isoforms.

  11. A nanobody directed to a functional epitope on VEGF, as a novel strategy for cancer treatment

    DEFF Research Database (Denmark)

    Farajpour, Zahra; Rahbarizadeh, Fatemeh; Kazemi, Bahram

    2014-01-01

    Compelling evidence suggests that vascular endothelial growth factor (VEGF), due to its essential role in angiogenesis, is a critical target for cancer treatment. Neutralizing monoclonal antibodies against VEGF are important class of drugs used in cancer therapy. However, the cost of production...

  12. Activation of protease-activated receptor 2 induces VEGF independently of HIF-1.

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    Jeppe Grøndahl Rasmussen

    Full Text Available BACKGROUND: Human adipose stem cells (hASCs can promote angiogenesis through secretion of proangiogenic factors such as vascular endothelial growth factor (VEGF. In other cell types, it has been shown that induction of VEGF is mediated by both protease activated receptor 2 (PAR2 and hypoxia inducible factor 1(HIF-1. The present study hypothesized that PAR2 stimulation through activation of kinase signaling cascades lead to induction of HIF-1 and secretion of VEGF. METHODOLOGY/PRINCIPAL FINDINGS: Immunohistochemistry revealed the expression of PAR2 receptors on the surface of hASCs. Blocking the PAR2 receptors with a specific antibody prior to trypsin treatment showed these receptors are involved in trypsin-evoked increase in VEGF secretion from hASCs. Blocking with specific kinase inhibitors suggested that that activation of MEK/ERK and PI3-kinase/Akt pathways are involved in trypsin-eveoked induction of VEGF. The effect of the trypsin treatment on the transcription of VEGF peaked at 6 hours after the treatment and was comparable to the activation observed after keeping hASCs for 24 hours at 1% oxygen. In contrast to hypoxia, trypsin alone failed to induce HIF-1 measured with ELISA, while the combination of trypsin and hypoxia had an additive effect on both VEGF transcription and secretion, results which were confirmed by Western blot. CONCLUSION: In hASCs trypsin and hypoxia induce VEGF expression through separate pathways.

  13. Discontinuation of anti-VEGF cancer therapy promotes metastasis through a liver revascularization mechanism

    DEFF Research Database (Denmark)

    Yang, Yunlong; Zhang, Yin; Iwamoto, Hideki

    2016-01-01

    The impact of discontinuation of anti-VEGF cancer therapy in promoting cancer metastasis is unknown. Here we show discontinuation of anti-VEGF treatment creates a time-window of profound structural changes of liver sinusoidal vasculatures, exhibiting hyper-permeability and enlarged open-pore size...

  14. A proteomic study of potential VEGF-C-associated proteins in bladder cancer T24 cells.

    Science.gov (United States)

    Zhang, Hui-hui; Qi, Fan; Zu, Xiong-bing; Cao, You-han; Miao, Jian-guang; Xu, Liang; Qi, Lin

    2012-11-01

    Overexpression of vascular endothelial growth factor-C (VEGF-C) has been found to play an important role in malignant progression of various cancer cells, in addition to lymphangiogenesis. However, the mechanisms involved are still largely unknown. Our early research has confirmed that the expression of VEGF-C in bladder cancer was markedly higher than that in normal bladder tissues. VEGF-C can also obviously promote proliferation and invasion of bladder cancer T24 cells. In the present work, we attempted to use proteomic analysis to screen out potential VEGF-C-associated proteins involved in malignant progression of the bladder cancer T24 cells. Lentivirus vector-based RNA interference (RNAi) was employed to diminish VEGF-C expression of bladder cancer T24 cells. Then we performed comparative proteome analysis to explore differentially expressed proteins in T24 cells with and without VEGF-C siRNA, by two-dimensional difference gel electrophoresis (2D-DIGE). Twenty-three proteins were identified. Some proteins (matrix metalloproteinase-9, Keratin 8, Serpin B5, Annexin A8) with significant differences were further confirmed by Western blotting. The 23 potential VEGF-C-associated proteins identified in our study provide us with further insights into the mechanism of VEGF-C promoting malignant progression of bladder cancer cells.

  15. Platelet activation determines angiopoietin-1 and VEGF levels in malaria: implications for their use as biomarkers

    NARCIS (Netherlands)

    Brouwers, J.; Noviyanti, R.; Fijnheer, R.; Groot, P.G. de; Trianty, L.; Mudaliana, S.; Roest, M.; Syafruddin, D.; Ven, A. van der; Mast, Q. de

    2013-01-01

    INTRODUCTION: The angiogenic proteins angiopoietin (Ang)-1, Ang-2 and vascular endothelial growth factor (VEGF) are regulators of endothelial inflammation and integrity. Since platelets store large amounts of Ang-1 and VEGF, measurement of circulation levels of these proteins is sensitive to

  16. Erythropoietin does not reduce plasma lactate, H+, and K+ during intense exercise

    DEFF Research Database (Denmark)

    Nordsborg, Nikolai Baastrup; Robach, P; Boushel, R

    2015-01-01

    It is investigated if recombinant human erythropoietin (rHuEPO) treatment for 15 weeks (n = 8) reduces extracellular accumulation of metabolic stress markers such as lactate, H(+) , and K(+) during incremental exhaustive exercise. After rHuEPO treatment, normalization of blood volume and composit...

  17. Effects of erythropoietin on emotional processing biases in patients with major depression: an exploratory fMRI study

    DEFF Research Database (Denmark)

    Miskowiak, Kamilla W; Favaron, Elisa; Hafizi, Sepehr

    2009-01-01

    INTRODUCTION: Erythropoietin (Epo) has neurotrophic effects and may be a novel therapeutic agent in the treatment of depression. We have found antidepressant-like effects of Epo on emotional processing and mood in healthy volunteers. OBJECTIVE: The current study aimed to explore the effects of Epo...

  18. Interactions of erythropoietin, granulocyte colony-stimulating factor, stem cell factor, and interleukin-11 on murine hematopoiesis during simultaneous administration

    NARCIS (Netherlands)

    Roeder, [No Value; de Haan, G; Engel, C; Nijhof, W; Dontje, B; Loeffler, M

    1998-01-01

    We investigated how in vivo effects of single hematopoietic cytokines change if given in combination for a prolonged time. Mice were treated with every combination of recombinant human (rh) erythropoietin (EPO), rh granulocyte colony-stimulating factor (G-CSF), recombinant rat (rr) stem cell factor

  19. Impact of hepcidin, interleukin 6, and other inflammatory markers with respect to erythropoietin on anemia in chronic hemodialysis patients

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    Ihab A. Ibrahim

    2014-01-01

    Conclusion Serum hepcidin levels were associated with iron status and inflammation in maintenance hemodialysis patients, and the high hepcidin serum levels, found in hemodialysis (HD patients, are dependent on the magnitude of the inflammatory process and on recombinant human erythropoietin doses. Hepcidin and its regulatory pathways are potential therapeutic targets, which could lead to effective treatment of anemia in chronic hemodialysis.

  20. Effects of an 8-weeks erythropoietin treatment on mitochondrial and whole body fat oxidation capacity during exercise in healthy males

    DEFF Research Database (Denmark)

    Guadalupe-Grau, Amelia; Plenge, Ulla; Helbo, Signe

    2015-01-01

    Abstract The present investigation was performed to elucidate if the non-erythropoietic ergogenic effect of a recombinant erythropoietin treatment results in an impact on skeletal muscle mitochondrial and whole body fatty acid oxidation capacity during exercise, myoglobin concentration and angiog...

  1. Determinants of Red Cell Distribution Width (RDW) in Cardiorenal Patients : RDW is Not Related to Erythropoietin Resistance

    NARCIS (Netherlands)

    Emans, Mireille E.; van der Putten, Karien; van Rooijen, Karlijn L.; Kraaijenhagen, Rob J.; Swinkels, Dorine; van Solinge, Wouter W.; Cramer, Maarten J.; Doevendans, Pieter A. F. M.; Braam, Branko; Gaillard, Carlo A. J. M.

    Background: Studies have shown that red cell distribution width (RDW) is related to outcome in chronic heart failure (CHF). The pathophysiological process is unknown. We studied the relationship between RDW and erythropoietin (EPO) resistance, and related factors such as erythropoietic activity,

  2. The ergogenic effect of recombinant human erythropoietin on VO2max depends on the severity of arterial hypoxemia

    DEFF Research Database (Denmark)

    Robach, Paul; Calbet, Jose A L; Thomsen, Jonas J

    2008-01-01

    Treatment with recombinant human erythropoietin (rhEpo) induces a rise in blood oxygen-carrying capacity (CaO(2)) that unequivocally enhances maximal oxygen uptake (VO(2)max) during exercise in normoxia, but not when exercise is carried out in severe acute hypoxia. This implies that there should ...

  3. Tumour cells expressing single VEGF isoforms display distinct growth, survival and migration characteristics.

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    Chryso Kanthou

    Full Text Available Vascular endothelial growth factor-A (VEGF is produced by most cancer cells as multiple isoforms, which display distinct biological activities. VEGF plays an undisputed role in tumour growth, vascularisation and metastasis; nevertheless the functions of individual isoforms in these processes remain poorly understood. We investigated the effects of three main murine isoforms (VEGF188, 164 and 120 on tumour cell behaviour, using a panel of fibrosarcoma cells we developed that express them individually under endogenous promoter control. Fibrosarcomas expressing only VEGF188 (fs188 or wild type controls (fswt were typically mesenchymal, formed ruffles and displayed strong matrix-binding activity. VEGF164- and VEGF120-producing cells (fs164 and fs120 respectively were less typically mesenchymal, lacked ruffles but formed abundant cell-cell contacts. On 3D collagen, fs188 cells remained mesenchymal while fs164 and fs120 cells adopted rounded/amoeboid and a mix of rounded and elongated morphologies respectively. Consistent with their mesenchymal characteristics, fs188 cells migrated significantly faster than fs164 or fs120 cells on 2D surfaces while contractility inhibitors accelerated fs164 and fs120 cell migration. VEGF164/VEGF120 expression correlated with faster proliferation rates and lower levels of spontaneous apoptosis than VEGF188 expression. Nevertheless, VEGF188 was associated with constitutively active/phosphorylated AKT, ERK1/2 and Stat3 proteins. Differences in proliferation rates and apoptosis could be explained by defective signalling downstream of pAKT to FOXO and GSK3 in fs188 and fswt cells, which also correlated with p27/p21 cyclin-dependent kinase inhibitor over-expression. All cells expressed tyrosine kinase VEGF receptors, but these were not active/activatable suggesting that inherent differences between the cell lines are governed by endogenous VEGF isoform expression through complex interactions that are independent of tyrosine

  4. Moving Past Anti-VEGF: Novel Therapies for Treating Diabetic Retinopathy.

    Science.gov (United States)

    Bolinger, Mark T; Antonetti, David A

    2016-09-07

    Diabetic retinopathy is the leading cause of blindness in working age adults, and is projected to be a significant future health concern due to the rising incidence of diabetes. The recent advent of anti-vascular endothelial growth factor (VEGF) antibodies has revolutionized the treatment of diabetic retinopathy but a significant subset of patients fail to respond to treatment. Accumulating evidence indicates that inflammatory cytokines and chemokines other than VEGF may contribute to the disease process. The current review examines the presence of non-VEGF cytokines in the eyes of patients with diabetic retinopathy and highlights mechanistic pathways in relevant animal models. Finally, novel drug targets including components of the kinin-kallikrein system and emerging treatments such as anti-HPTP (human protein tyrosine phosphatase) β antibodies are discussed. Recognition of non-VEGF contributions to disease pathogenesis may lead to novel therapeutics to enhance existing treatments for patients who do not respond to anti-VEGF therapies.

  5. Estimation of Immunohistochemical Expression of VEGF in Ductal Carcinomas of the Breast

    DEFF Research Database (Denmark)

    Maae, Else; Nielsen, Martin; Dahl Steffensen, Karina

    2012-01-01

    Introduction: Vascular endothelial growth factor A (VEGF-A) is a very important growth factor in angiogenesis and holds the potential as both a predictive marker for anti-angiogenic cancer treatment and as a prognostic variable. Consequently, reliable estimation of VEGF expression is crucial....... Material and methods: We immunostained whole tumor sections for VEGF-A, -B, and VEGFR-1 of invasive ductal carcinomas of the breast and scored the tumors manually by staining intensity as the only parameter and by a combination of qualitative and quantitative staining information. We also introduced...... measurements of VEGF-A, VEGF-B and VEGFR-1 when analyzing whole tumor sections of invasive ductal breast carcinomas....

  6. Interferon decreases VEGF levels in patients with chronic myeloid leukemia treated with imatinib.

    Science.gov (United States)

    Legros, L; Guilhot, J; Huault, S; Mahon, F X; Preudhomme, C; Guilhot, F; Hueber, A O

    2014-06-01

    In chronic myeloid leukemia (CML), evidence is supporting the role of VEGF in growth, and survival of leukemia cells. The evaluation of plasma VEGF levels in 403 CML patients randomized within SPIRIT study to received imatinib-400mg versus imatinib+cytarabine versus imatinib+interferon (IFN) versus imatinib-600mg demonstrated that VEGF is an independent factor of BCR-ABL burden. VEGF low levels at diagnosis were associated with a progression-free survival of 100% at 48 months. Under treatment, significant lowest levels were observed in imatinib+IFN arm. These results support the use of VEGF as a parameter to predict CML evolution and let us to speculate about antiangiogenic properties of IFN. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. VEGF may contribute to macrophage recruitment and M2 polarization in the decidua.

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    Karen C Wheeler

    Full Text Available It is increasingly evident that cytokines and growth factors produced in the decidua play a pivotal role in the regulation of the local immune microenvironment and the establishment of pregnancy. One of the major growth factors produced in the decidua is vascular endothelial growth factor (VEGF, which acts not only on endothelial cells, but also on multiple other cell types, including macrophages. We sought to determine whether decidua-derived VEGF affects macrophage recruitment and polarization using human endometrial/decidual tissue samples, primary human endometrial stromal cells (ESCs, and the human monocyte cell line THP1. In situ hybridization was used for assessment of local VEGF expression and immunohistochemistry was used for identification and localization of CD68-positive endometrial macrophages. Macrophage migration in culture was assessed using a transwell migration assay, and the various M1/M2 phenotypic markers and VEGF expression were assessed using quantitative real-time PCR (qRT-PCR. We found dramatic increases in both VEGF levels and macrophage numbers in the decidua during early pregnancy compared to the secretory phase endometrium (non-pregnant, with a significant increase in M2 macrophage markers, suggesting that M2 is the predominant macrophage phenotype in the decidua. However, decidual samples from preeclamptic pregnancies showed a significant shift in macrophage phenotype markers, with upregulation of M1 and downregulation of M2 markers. In THP1 cultures, VEGF treatment significantly enhanced macrophage migration and induced M1 macrophages to shift to an M2 phenotype. Moreover, treatment with conditioned media from decidualized ESCs induced changes in macrophage migration and polarization similar to that of VEGF treatment. These effects were abrogated by the addition of a potent VEGF inhibitor. Together these results suggest that decidual VEGF plays a significant role in macrophage recruitment and M2 polarization, and

  8. VEGF and IL-18 in induced sputum of lung cancer patients.

    Science.gov (United States)

    Rovina, Nikoletta; Hillas, Georgios; Dima, Efrossini; Vlastos, Fotis; Loukides, Stylianos; Veldekis, Dimitrios; Roussos, Charis; Alhanatis, Manos; Bakakos, Petros

    2011-06-01

    Cytokines are key players in the biological processes of malignant tumors and special interest has been focused on cytokines exerting tumor and anti-tumor properties, such as vascular endothelial growth factor (VEGF) and Interleukin-18 (IL-18). Aim of this study was to assess IL-18 and VEGF levels in induced sputum of lung cancer patients at diagnosis, and assess their possible association with the histological type of cancer, the stage and the overall patient survival. Seventy six patients with a diagnosis of lung cancer were recruited and were followed up for 48months. Thirteen healthy smokers and 16 healthy non-smokers were used as control groups. VEGF and IL-18 were measured by ELISA in sputum supernatants at the time of diagnosis. Lung cancer patients had significantly higher baseline IL-18 and VEGF levels compared to healthy controls (p<0.001). No difference was found in IL-18 and VEGF levels between the various stages in non-small cell lung cancer (NSCLC) and between limited and extended small cell lung cancer (SCLC). However, the ratio of VEGF/IL-18 was significantly higher in NSCLC compared to SCLC patients (p=0.018). In extended SCLC overall survival was inversely associated with baseline sputum VEGF levels (p=0.034) and estimated mortality risk was 1.14 (95% CI 1.006-1.283) for an increase of 100pg/ml in VEGF levels. Such association was not found regarding baseline IL-18 levels. VEGF levels in induced sputum may have a prognostic role in the survival of SCLC. The ratio VEGF/IL-18 in induced sputum differs between NSCLC and SCLC, indicating differences in angiogenesis mechanisms and/or immunological response in these two major histological types of lung cancer. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. The treatment of femoral neck fracture using VEGF-loaded nanographene coated internal fixation screws.

    Science.gov (United States)

    Li, Shuo; Yuan, Hengfeng; Pan, Jianfeng; Fan, Wenshuai; Zhu, Liang; Yan, Zuoqin; Guo, Changan

    2017-01-01

    Previous studies have proved that vascular endothelial growth factor (VEGF) has a dual role in the promotion of new bone formation and blood vessel repair during fracture healing. However, how to introduce VEGF to a fracture site safely and effectively is still a challenge. This study aimed to prepare a VEGF-loaded nanographene coated internal fixation screw and to evaluate its effects in the treatment of femoral neck fracture. Nanographene coated screws were prepared by direct liquid-phase exfoliation of the graphite method, and the surface characteristics were observed through scanning electron microscopy (SEM). VEGF was loaded on nanographene coatings through physical adsorption, and the VEGF controlled release was examined by ELISA. Then a canine femoral neck fracture model was built to examine both the angiogenic and osteogenic properties of the VEGF-loaded coated screws. X-ray, micro-CT-based microangiography, and histopathologic evaluation were used to assess the fracture healing progress. The results demonstrated that nanographene could load VEGF effectively, and the accumulative release of VEGF clearly increased during the entire testing period (9 days) without burst release. In canine fracture models, the results of X-ray, microangiography, and histopathologic examination proved that the speed of fracture healing, new bone formation area, and revascularization of the fractured femoral heads in the VEGF-loaded coated screws groups were significantly higher than in the control groups. Our study proved that VEGF-loaded nanographene coated screws were effective in the treatment of femoral neck fracture and prevention of avascular necrosis of femoral head.

  10. Sustained delivery of VEGF from designer self-assembling peptides improves cardiac function after myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hai-dong [Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203 (China); Cui, Guo-hong; Yang, Jia-jun [Department of Neurology, Shanghai No. 6 People' s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200233 (China); Wang, Cun [Institutes of Biomedical Sciences, Fudan University, Shanghai 200032 (China); Zhu, Jing; Zhang, Li-sheng; Jiang, Jun [Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203 (China); Shao, Shui-jin, E-mail: shaoshuijin@163.com [Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203 (China)

    2012-07-20

    Highlights: Black-Right-Pointing-Pointer The designer peptide LRKKLGKA could self-assemble into nanofibers. Black-Right-Pointing-Pointer Injection of LRKKLGKA peptides could promote the sustained delivery of VEGF. Black-Right-Pointing-Pointer Injection of VEGF with LRKKLGKA peptides lead to sufficient angiogenesis. Black-Right-Pointing-Pointer Injection of VEGF with LRKKLGKA peptides improves heart function. -- Abstract: Poor vascularization and insufficient oxygen supply are detrimental to the survival of residual cardiomyocytes or transplanted stem cells after myocardial infarction. To prolong and slow the release of angiogenic factors, which stimulate both angiogenesis and vasculogenesis, we constructed a novel self-assembling peptide by attaching the heparin-binding domain sequence LRKKLGKA to the self-assembling peptide RADA16. This designer self-assembling peptide self-assembled into nanofiber scaffolds under physiological conditions, as observed by atomic force microscopy. The injection of designer self-assembling peptides can efficiently provide the sustained delivery of VEGF for at least 1 month. At 4 weeks after transplantation, cardiac function was improved, and scar size and collagen deposition were markedly reduced in the group receiving VEGF with the LRKKLGKA scaffolds compared with groups receiving VEGF alone, LRKKLGKA scaffolds alone or VEGF with RADA16 scaffolds. The microvessel density in the VEGF with LRKKLGKA group was higher than that in the VEGF with RADA16 group. TUNEL and cleaved caspase-3 expression assays showed that the transplantation of VEGF with LRKKLGKA enhanced cell survival in the infarcted heart. These results present the tailor-made peptide scaffolds as a new generation of sustained-release biomimetic biomaterials and suggest that the use of angiogenic factors along with designer self-assembling peptides can lead to myocardial protection, sufficient angiogenesis, and improvement in cardiac function.

  11. Profiling of microRNAs in AML cells following overexpression or silencing of the VEGF gene.

    Science.gov (United States)

    Li, Li; Zhu, Lixia; Wang, Yungui; Zhou, De; Zhu, Jingjing; Xie, Wanzhuo; Ye, Xiujin

    2017-01-01

    Acute myeloid leukemia (AML) is a disease of the hematopoietic progenitor cells associated with heterogeneous clonal proliferation. Vascular endothelial growth factor (VEGF) and its receptors play important roles in the regulation of angiogenesis during physiological and pathological processes. It is thought that AML cells have an autocrine VEGF pathway that contributes to the development and progression of AML. In addition, growing evidence has suggested that numerous microRNAs are involved in AML. The present study aimed to investigate the relationship between VEGF dysregulation and microRNA profiles in AML cells and patients. VEGF-overexpressing and VEGF-knockdown leukemia cells were constructed and changes in the patterns of microRNA expression were analyzed using a microRNA array. Subsequently, mononuclear cells from the blood of patients with AML showing high or low expression levels of VEGF were obtained and were used to assess the patterns of microRNA expression by reverse transcription-quantitative polymerase chain reaction. The results of the present study suggested that downregulation of VEGF markedly altered the profile of microRNAs in AML cells, while upregulation of VEGF did not. Examination of clinical samples from patients with AML showed that several microRNAs were closely associated with the expression level of VEGF, including miR-20a, miR-93, miR-16-5p, miR-17-5p, miR-124-5p and miR-17-3p. These results suggested that VEGF may be a pivotal protein that can both receive and initiate signals in leukemia cells.

  12. Overview of the Safety of Anti-VEGF Drugs: Analysis of the Italian Spontaneous Reporting System.

    Science.gov (United States)

    Cutroneo, Paola Maria; Giardina, Claudia; Ientile, Valentina; Potenza, Simona; Sottosanti, Laura; Ferrajolo, Carmen; Trombetta, Costantino J; Trifirò, Gianluca

    2017-11-01

    Anti-vascular endothelial growth factor (anti-VEGF) drugs are widely used for the treatment of several cancers and retinal diseases. The systemic use of anti-VEGF drugs has been associated with an increased risk of serious adverse reactions. Whether this risk is also related to intravitreal administration of anti-VEGF drugs is unclear. The aim of this study was to provide an overview of the safety of anti-VEGF drugs in oncology and ophthalmology settings using the Italian Spontaneous Reporting System (SRS). We selected all suspected adverse drug reaction (ADR) reports attributed to anti-VEGF drugs and conducted descriptive frequency analyses stratified by indication of use. As a measure of disproportionality, we calculated the proportional reporting ratio with 95% confidence intervals at the level of standardized Medical Dictionary for Regulatory Activities (MedDRA ® ) queries (SMQs). Of a total of 2472 anti-VEGF drug-related reports, 2173 (87.9%) and 299 (12.1%) were attributed to systemic and intravitreal use of these drugs, respectively. The frequency of serious ADRs reported was higher for intravitreal administration of anti-VEGF drugs than for systemic use in patients with cancer (58.9 vs. 34.1%) (p < 0.001) and were disproportionally associated with ischemic heart disease and thromboembolic and cerebrovascular events. Most serious ADRs related to anti-VEGF drugs in patients with cancer are known and clinically relevant (e.g., gastrointestinal and vascular disorders). This study documented that serious ADRs and systemic toxicity may occur not only with systemic use of anti-VEGF drugs in patients with cancer but also with intravitreal administration. Close monitoring of cardio/cerebrovascular adverse events should be considered during treatment with all anti-VEGF drugs.

  13. Effects of ganglioside G(M1 and erythropoietin on spinal cord lesions in rats: functional and histological evaluations

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    Raphael Martus Marcon

    Full Text Available OBJECTIVE: To evaluate the functional and histological effects of ganglioside G(M1 and erythropoietin after experimental spinal cord contusion injury. METHODS: Fifty male Wistar rats underwent experimental spinal cord lesioning using an NYU-Impactor device and were randomly divided into the following groups, which received treatment intraperitoneally. The G(M1 group received ganglioside G(M1 (30 mg/kg; the erythropoietin group received erythropoietin (1000 IU/kg; the combined group received both drugs; and the saline group received saline (0.9% as a control. A fifth group was the laminectomy group, in which the animals were subjected to laminectomy alone, without spinal lesioning or treatment. The animals were evaluated according to the Basso, Beattie and Bresnahan (BBB scale, motor evoked potential recordings and, after euthanasia, histological analysis of spinal cord tissue. RESULTS: The erythropoietin group had higher BBB scores than the G(M1 group. The combined group had the highest BBB scores, and the saline group had the lowest BBB scores. No significant difference in latency was observed between the three groups that underwent spinal cord lesioning and intervention. However, the combined group showed a significantly higher signal amplitude than the other treatment groups or the saline group (p<0.01. Histological tissue analysis showed no significant difference between the groups. Axonal index was significantly enhanced in the combined group than any other intervention (p<0.01. CONCLUSION: G(M1 and erythropoietin exert therapeutic effects on axonal regeneration and electrophysiological and motor functions in rats subjected to experimental spinal cord lesioning and administering these two substances in combination potentiates their effects.

  14. Comparison of lymphatic vessel density and expression of VEGF-C and VEGF-D lymphangiogenic factors in Warthin's tumours and oncocytic adenomas.

    Science.gov (United States)

    Hoza, Jiri; Salzman, Richard; Bakaj, Tomas; Kucerova, Ladislava; Starek, Ivo

    2017-11-02

    To compare the density of lymphatic vessels and VEGF-C and VEGF-D expression in Warthin's tumours (WTs) and oncocytic adenomas (OCAs). Twenty three WTs and 13 OCAs of the parotid gland were analyzed. Lymphatic vessels were detected using the D2-40 antibody. For evaluation of the intratumour and peritumour lymphatic vessel density (iLVD and pLVD, respectively) the area of greatest vascularisation (hot spots) was chosen, using a ×40 field, and the number of vessels per square millimeter was counted in a ×200 field. The staining intensity for VEGF-C and VEGF-D immunoreaction in the tumour cells was graded from 0 to 3. The mean iLVD and pLVD values in WTs was 4.7 (range 1-8) and 6.9 (range 3-10), those in the OCAs 1.0 (range 0-3) and 5.8 (range 2-8), respectively. The differences in the iLVD, but not pLVD between the two tumour groups were statistically significant. In both entities, the pLVD markedly outnumbered the iLVD. The intratumour vessels in the WTs were present exclusively in the lymphoid stroma. In the group of 23 WTs, 13 (56.6%), 17 (73.9%) and 10 (43.4%) samples revealed positive VEGF-C, VEGF-D and both immunoreactions, respectively. 10 of 13 (77%) cases revealed VEGF-D immunoreaction and in none of them was the VEGF-C reaction present. The tumours had a comparable high density of peritumorous lymphatic network. However, WTs markedly differed from OCAs in the number of the intratumorous vessels. These were abundant solely in the stroma of WT, while practically lacking in the neoplastic epithelium of the WT and relatively rare in OCAs. We suggest that homeostasis in both entities is mediated mainly by peritumorous lymphatics. The lymphatic drainage in WTs is also fostered exclusively by stromal lymphatics, whereas in stroma poor OCAs by the vessels present in their neoplastic epithelium. We also believe that WTs stimulate proliferation of pre-existing lymphatic capillaries by means of the paracrine secretion of VEGF-C and VEGF-D in the neoplastic as well

  15. Post-radiation increase in VEGF enhances glioma cell motility in vitro

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    Kil Whoon

    2012-02-01

    Full Text Available Abstract Background Glioblastoma multiforme (GBM is among the most lethal of all human tumors, with frequent local recurrences after radiation therapy (RT. The mechanism accounting for such a recurrence pattern is unclear. It has classically been attributed to local recurrence of treatment-resistant cells. However, accumulating evidence suggests that additional mechanisms exist that involve the migration of tumor or tumor stem cells from other brain regions to tumor bed. VEGFs are well-known mitogens and can be up-regulated after RT. Here, we examine the effect of irradiation-induced VEGF on glioma cell motility. Materials and methods U251 and LN18 cell lines were used to generate irradiated-conditioned medium (IR-CM. At 72 h after irradiation, the supernatants were harvested. VEGF level in IR-CM was quantified by ELISA, and expression levels for VEGF mRNA were detected by RT-PCR. In vitro cancer cell motility was measured in chambers coated with/without Matrigel and IR-CM as a cell motility enhancer and a VEGF antibody as a neutralizer of VEGF bioactivity. Immunoblots were performed to evaluate the activity of cell motility-related kinases. Proliferation of GBM cells after treatment was measured by flow cytometry. Results Irradiation increased the level of VEGF mRNA that was mitigated by pre-RT exposure to Actinomycin D. U251 glioma cell motility (migration and invasion was enhanced by adding IR-CM to un-irradiated cells (174.9 ± 11.4% and 334.2 ± 46% of control, respectively. When we added VEGF antibody to IR-CM, this enhanced cell motility was negated (110.3 ± 12.0% and 105.7 ± 14.0% of control, respectively. Immunoblot analysis revealed that IR-CM increased phosphorylation of VEGF receptor-2 (VEGFR2 secondary to an increase in VEGF, with a concomitant increase of phosphorylation of the downstream targets (Src and FAK. Increased phosphorylation was mitigated by adding VEGF antibody to IR-CM. There was no difference in the mitotic index of

  16. (-)-Epigallocatechin-3-gallate inhibits VEGF expression induced by IL-6 via Stat3 in gastric cancer

    Science.gov (United States)

    Zhu, Bao-He; Chen, Hua-Yun; Zhan, Wen-Hua; Wang, Cheng-You; Cai, Shi-Rong; Wang, Zhao; Zhang, Chang-Hua; He, Yu-Long

    2011-01-01

    AIM: To demonstrate that (-)-Epigallocatechin-3-gallate (EGCG) inhibits vascular endothelial growth factor (VEGF) expression and angiogenesis induced by interleukin-6 (IL-6) via suppressing signal transducer and activator of transcription 3 (Stat3) activity in gastric cancer. METHODS: Human gastric cancer (AGS) cells were treated with IL-6 (50 ng/mL) and EGCG at different concentrations. VEGF, total Stat3 and activated Stat3 protein levels in the cell lyses were examined by Western blotting, VEGF protein level in the conditioned medium was measured by enzyme-linked immunosorbent assay, and the level of VEGF mRNA was evaluated by reverse transcription polymerase chain reaction (RT-PCR). Stat3 nuclear translocation was determined by Western blotting with nuclear extract, and Stat3-DNA binding activity was examined with Chromatin immunoprecipitation (ChIP) assay. IL-6 induced endothelial cell proliferation was measured with 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazoliumbromide assay, in vitro angiogenesis was determined with endothelial cell tube formation assay in Matrigel, and IL-6-induced angiogenesis in vitro was measured with Matrigel plug assay. RESULTS: There was a basal expression and secretion of VEGF in AGS cells. After stimulation with IL-6, VEGF expression was apparently up-regulated and a 2.4-fold increase was observed. VEGF secretion in the conditioned medium was also increased by 2.8 folds. When treated with EGCG, VEGF expression and secretion were dose-dependently decreased. IL-6 also increased VEGF mRNA expression by 3.1 folds. EGCG treatment suppressed VEGF mRNA expression in a dose-dependent manner. EGCG dose-dependently inhibited Stat3 activation induced by IL-6, but did not change the total Stat3 expression. When treated with EGCG or AG490, VEGF expressions were reduced to the level or an even lower level in the tumor cells not stimulated with IL-6. However, PD98059 and LY294002 did not change VEGF expression induced by IL-6. EGCG

  17. Integrin-specific hydrogels functionalized with VEGF for vascularization and bone regeneration of critical-size bone defects

    Science.gov (United States)

    García, José R.; Clark, Amy Y.; García, Andrés J.

    2016-01-01

    Vascularization of bone defects is considered a crucial component to the successful regeneration of large bone defects. Although vascular endothelial growth factor (VEGF) has been delivered to critical-size bone defect models to augment blood vessel infiltration into the defect area, its potential to increase bone repair remains ambiguous. In this study, we investigated whether integrin-specific biomaterials modulate the effects of VEGF on bone regeneration. We engineered protease-degradable, VEGF-loaded polyethylene glycol (PEG) hydrogels functionalized with either a triple-helical, α2β1 integrin-specific peptide (GFOGER) or an αvβ3 integrin-targeting peptide (RGD). Covalent incorporation of VEGF into the PEG hydrogel allowed for protease degradation-dependent release of the protein while maintaining VEGF bioactivity. When applied to critical-size segmental defects in the murine radius, GFOGER-functionalized VEGF-free hydrogels exhibited significantly increased vascular volume and density and resulted in a larger number of thicker blood vessels compared to RGD-functionalized VEGF-free hydrogels. VEGF-loaded RGD hydrogels increased vascularization compared to VEGF-free RGD hydrogels, but the levels of vascularization for these VEGF-containing RGD hydrogels were similar to those of VEGF-free GFOGER hydrogels. VEGF transiently increased bone regeneration in RGD hydrogels but had no effect at later time points. In GFOGER hydrogels, VEGF did not show an effect on bone regeneration. However, VEGF-free GFOGER hydrogels resulted in increased bone regeneration compared to VEGF-free RGD hydrogels. These findings demonstrate the importance of integrin-specificity in engineering constructs for vascularization and associated bone regeneration. PMID:26662727

  18. Pericardial fluid and serum VEGF in response to different types of heparin treatment.

    Science.gov (United States)

    Gerrah, Rabin; Tshori, Sagi; Gilon, Dan

    2004-04-01

    Heparin is an important medication in the treatment of patients with unstable angina pectoris. We designed an observational study to compare the effects of standard heparin (SH) with low molecular weight heparin (LMWH) on vascular endothelial growth factor (VEGF) levels in patients undergoing coronary artery bypass grafting (CABG). Thirty-two patients with unstable angina pectoris undergoing CABG were prospectively categorized into two groups according to the type of heparin administration before surgery. VEGF levels determined by enzyme linked immunosorbent assay (ELISA) were compared between the two groups' blood samples obtained before the surgery and pericardial fluid after pericardial opening. There was no difference in preoperative characteristics between the two groups. Serum VEGF levels were similar (P=0.3) in patients treated by SH (85+/-55 pg/ml) compared to those treated with LMWH (105+/-64 pg/ml). VEGF levels in the pericardial fluid were significantly raised (P<0.0001) in patients of LMWH group (36+/-13 pg/ml) compared to SH group (13+/-6 pg/ml). A good correlation was observed between VEGF in the serum and platelet count in both SH group (r=0.8) and LMWH group (r=0.7). Local response of the ischemic myocardium, as expressed by VEGF levels, differs in patients treated with SH compared to patients treated with LMWH. VEGF levels in pericardial fluid of patients receiving LMWH were 2-3-folds higher than patients in SH group.

  19. Serum VEGF levels are related to the presence of pulmonary arterial hypertension in systemic sclerosis

    Directory of Open Access Journals (Sweden)

    Sakkas Lazaros

    2009-05-01

    Full Text Available Abstract Background The association between systemic sclerosis and pulmonary arterial hypertension (PAH is well recognized. Vascular endothelial growth factor (VEGF has been reported to play an important role in pulmonary hypertension. The aim of the present study was to examine the relationship between systolic pulmonary artery pressure, clinical and functional manifestations of the disease and serum VEGF levels in systemic sclerosis. Methods Serum VEGF levels were measured in 40 patients with systemic sclerosis and 13 control subjects. All patients underwent clinical examination, pulmonary function tests and echocardiography. Results Serum VEGF levels were higher in systemic sclerosis patients with sPAP ≥ 35 mmHg than in those with sPAP LCO were independent predictors of systolic pulmonary artery pressure. Conclusion Serum VEGF levels are increased in systemic sclerosis patients with sPAP ≥ 35 mmHg. The correlation between VEGF levels and systolic pulmonary artery pressure may suggest a possible role of VEGF in the pathogenesis of PAH in systemic sclerosis.

  20. VEGF-mediated angiogenesis stimulates neural stem cell proliferation and differentiation in the premature brain

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jinqiao, E-mail: jinqiao1977@163.com [Institute of Pediatrics, Children' s Hospital of Fudan University (China); Sha, Bin [Department of Neonatology, Children' s Hospital of Fudan University, 399 Wanyuan Road, Shanghai 201102 (China); Zhou, Wenhao, E-mail: zhou_wenhao@yahoo.com.cn [Department of Neonatology, Children' s Hospital of Fudan University, 399 Wanyuan Road, Shanghai 201102 (China); Yang, Yi [Institute of Pediatrics, Children' s Hospital of Fudan University (China)

    2010-03-26

    This study investigated the effects of angiogenesis on the proliferation and differentiation of neural stem cells in the premature brain. We observed the changes in neurogenesis that followed the stimulation and inhibition of angiogenesis by altering vascular endothelial growth factor (VEGF) expression in a 3-day-old rat model. VEGF expression was overexpressed by adenovirus transfection and down-regulated by siRNA interference. Using immunofluorescence assays, Western blot analysis, and real-time PCR methods, we observed angiogenesis and the proliferation and differentiation of neural stem cells. Immunofluorescence assays showed that the number of vWF-positive areas peaked at day 7, and they were highest in the VEGF up-regulation group and lowest in the VEGF down-regulation group at every time point. The number of neural stem cells, neurons, astrocytes, and oligodendrocytes in the subventricular zone gradually increased over time in the VEGF up-regulation group. Among the three groups, the number of these cells was highest in the VEGF up-regulation group and lowest in the VEGF down-regulation group at the same time point. Western blot analysis and real-time PCR confirmed these results. These data suggest that angiogenesis may stimulate the proliferation of neural stem cells and differentiation into neurons, astrocytes, and oligodendrocytes in the premature brain.

  1. Development of VEGF-loaded PLGA matrices in association with mesenchymal stem cells for tissue engineering

    Directory of Open Access Journals (Sweden)

    A.R. Rosa

    Full Text Available The association of bioactive molecules, such as vascular endothelial growth factor (VEGF, with nanofibers facilitates their controlled release, which could contribute to cellular migration and differentiation in tissue regeneration. In this research, the influence of their incorporation on a polylactic-co-glycolic acid (PLGA scaffold produced by electrospinning on cell adhesion and viability and cytotoxicity was carried out in three groups: 1 PLGA/BSA/VEGF; 2 PLGA/BSA, and 3 PLGA. Morphology, fiber diameter, contact angle, loading efficiency and controlled release of VEGF of the biomaterials, among others, were measured. The nanofibers showed smooth surfaces without beads and with interconnected pores. PLGA/BSA/VEGF showed the smallest water contact angle and VEGF released for up to 160 h. An improvement in cell adhesion was observed for the PLGA/BSA/VEGF scaffolds compared to the other groups and the scaffolds were non-toxic for the cells. Therefore, the scaffolds were shown to be a good strategy for sustained delivery of VEGF and may be a useful tool for tissue engineering.

  2. Rapamycin Inhibits Proliferation of Hemangioma Endothelial Cells by Reducing HIF-1-Dependent Expression of VEGF

    Science.gov (United States)

    Medici, Damian; Olsen, Bjorn R.

    2012-01-01

    Hemangiomas are tumors formed by hyper-proliferation of vascular endothelial cells. This is caused by elevated vascular endothelial growth factor (VEGF) signaling through VEGF receptor 2 (VEGFR2). Here we show that elevated VEGF levels produced by hemangioma endothelial cells are reduced by the mTOR inhibitor rapamycin. mTOR activates p70S6K, which controls translation of mRNA to generate proteins such as hypoxia inducible factor-1 (HIF-1). VEGF is a known HIF-1 target gene, and our data show that VEGF levels in hemangioma endothelial cells are reduced by HIF-1α siRNA. Over-expression of HIF-1α increases VEGF levels and endothelial cell proliferation. Furthermore, both rapamycin and HIF-1α siRNA reduce proliferation of hemangioma endothelial cells. These data suggest that mTOR and HIF-1 contribute to hemangioma endothelial cell proliferation by stimulating an autocrine loop of VEGF signaling. Furthermore, mTOR and HIF-1 may be therapeutic targets for the treatment of hemangiomas. PMID:22900063

  3. Experimental studies of a vaccine formulation of recombinant human VEGF antigen with aluminum phosphate.

    Science.gov (United States)

    Pérez Sánchez, Lincidio; Morera Díaz, Yanelys; Bequet-Romero, Mónica; Ramses Hernández, Gerardo; Rodríguez, Yadira; Castro Velazco, Jorge; Puente Pérez, Pedro; Ayala Avila, Marta; Gavilondo, Jorge V

    2015-01-01

    CIGB-247 is a cancer vaccine that is a formulation of a recombinant protein antigen representative of the human vascular endothelial growth factor (VEGF) with a bacterially-derived adjuvant (VSSP). The vaccine has shown an excellent safety profile in mice, rats, rabbits, not-human primates and in recent clinical trials in cancer patients. Response to the vaccine is characterized by specific antibody titers that neutralize VEGF/VEGFR2 binding and a cytotoxic tumor-specific response. To expand our present anti-VEGF active immunotherapy strategies, we have now studied in mice and non-human primates the effects of vaccination with a formulation of our recombinant VEGF antigen and aluminum phosphate adjuvant (hereafter denominated CIGB-247-A). Administered bi-weekly, CIGB-247-A produces high titers of anti-VEGF IgG blocking antibodies in 2 mice strains. Particularly in BALB/c, the treatment impaired subcutaneous F3II mammary tumor growth and reduced the number of spontaneous lung macro metastases, increasing animals' survival. Spleen cells from specifically immunized mice directly killed F3II tumor cells in vitro. CIGB-247-A also showed to be immunogenic in non-human primates, which developed anti-VEGF blocking antibodies and the ability for specific direct cell cytotoxic responses, all without impairing the healing of deep skin wounds or other side effect. Our results support consideration of aluminum phosphate as a suitable adjuvant for the development of new vaccine formulations using VEGF as antigen.

  4. WISP-1 positively regulates angiogenesis by controlling VEGF-A expression in human osteosarcoma.

    Science.gov (United States)

    Tsai, Hsiao-Chi; Tzeng, Huey-En; Huang, Chun-Yin; Huang, Yuan-Li; Tsai, Chun-Hao; Wang, Shih-Wei; Wang, Po-Chuan; Chang, An-Chen; Fong, Yi-Chin; Tang, Chih-Hsin

    2017-04-13

    In recent years, much research has focused on the role of angiogenesis in osteosarcoma, which occurs predominantly in adolescents and young adults. The vascular endothelial growth factor-A (VEGF-A) pathway is the key regulator of angiogenesis and in osteosarcoma. VEGF-A expression has been recognized as a prognostic marker in angiogenesis. Aberrant WNT1-inducible signaling pathway protein-1 (WISP-1) expression is associated with various cancers. However, the function of WISP-1 in osteosarcoma angiogenesis is poorly understood. We demonstrate a positive correlation between WISP-1 and VEGF-A expression in human osteosarcoma. Moreover, we show that WISP-1 promotes VEGF-A expression in human osteosarcoma cells, subsequently inducing human endothelial progenitor cell (EPC) migration and tube formation. The focal adhesion kinase (FAK), Jun amino-terminal kinase (JNK), and hypoxia-inducible factor (HIF)-1α signaling pathways were activated after WISP-1 stimulation, while FAK, JNK, and HIF-1α inhibitors or small interfering RNA (siRNA) abolished WISP-1-induced VEGF-A expression and angiogenesis. In vitro and in vivo studies revealed down-regulation of microRNA-381 (miR-381) in WISP-1-induced VEGF-A expression and angiogenesis. Our findings reveal that WISP-1 enhances VEGF-A expression and angiogenesis through the FAK/JNK/HIF-1α signaling pathways, as well as via down-regulation of miR-381 expression. WISP-1 may be a promising target in osteosarcoma angiogenesis.

  5. Mussel-inspired immobilization of vascular endothelial growth factor (VEGF) for enhanced endothelialization of vascular grafts.

    Science.gov (United States)

    Shin, Young Min; Lee, Yu Bin; Kim, Seok Joo; Kang, Jae Kyeong; Park, Jong-Chul; Jang, Wonhee; Shin, Heungsoo

    2012-07-09

    Most polymeric vascular prosthetic materials have low patency rate for replacement of small diameter vessels (polydopamine-mediated immobilization of growth factors on the surface of polymeric materials as a versatile tool to modify surface characteristics of vascular grafts potentially for accelerated endothelialization. Polydopamine was deposited on the surface of biocompatible poly(L-lactide-co-ε-caprolactone) (PLCL) elastomer, on which vascular endothelial growth factor (VEGF) was subsequently immobilized by simple dipping. Surface characteristics and composition were investigated by using scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. Immobilization of VEGF on the polydopamine-deposited PLCL films was effective (19.8 ± 0.4 and 197.4 ± 19.7 ng/cm(2) for DPv20 and DPv200 films, respectively), and biotin-mediated labeling of immobilized VEGF revealed that the fluorescence intensity increased as a function of the concentration of VEGF solution. The effect of VEGF on adhesion of HUVECs was marginal, which may have been masked by polydopamine layer that also enhanced cell adhesion. However, VEGF-immobilized substrate significantly enhanced proliferation of HUVECs for over 7 days of in vitro culture and also improved their migration. In addition, immobilized VEGF supported robust cell to cell interactions with strong expression of CD 31 marker. The same process was effective for immobilization of basic fibroblast growth factor, demonstrating the robustness of polydopamine layer for secondary ligation of growth factors as a simple and novel surface modification strategy for vascular graft materials.

  6. Rapamycin inhibits proliferation of hemangioma endothelial cells by reducing HIF-1-dependent expression of VEGF.

    Directory of Open Access Journals (Sweden)

    Damian Medici

    Full Text Available Hemangiomas are tumors formed by hyper-proliferation of vascular endothelial cells. This is caused by elevated vascular endothelial growth factor (VEGF signaling through VEGF receptor 2 (VEGFR2. Here we show that elevated VEGF levels produced by hemangioma endothelial cells are reduced by the mTOR inhibitor rapamycin. mTOR activates p70S6K, which controls translation of mRNA to generate proteins such as hypoxia inducible factor-1 (HIF-1. VEGF is a known HIF-1 target gene, and our data show that VEGF levels in hemangioma endothelial cells are reduced by HIF-1α siRNA. Over-expression of HIF-1α increases VEGF levels and endothelial cell proliferation. Furthermore, both rapamycin and HIF-1α siRNA reduce proliferation of hemangioma endothelial cells. These data suggest that mTOR and HIF-1 contribute to hemangioma endothelial cell proliferation by stimulating an autocrine loop of VEGF signaling. Furthermore, mTOR and HIF-1 may be therapeutic targets for the treatment of hemangiomas.

  7. Post-treatment Effects of Erythropoietin and Nordihydroguaiaretic Acid on Recovery from Cisplatin-induced Acute Renal Failure in the Rat

    OpenAIRE

    Lee, Dong Won; Kwak, Ihm Soo; Lee, Soo Bong; Song, Sang Heon; Seong, Eun Young; Yang, Byeong Yun; Lee, Min Young; SOL, MEE YOUNG

    2009-01-01

    5-Lipoxygenase inhibitor and human recombinant erythropoietin might accelerate renal recovery in cisplatin-induced acute renal failure rats. Male Sprague-Dawley rats were randomized into four groups: 1) normal controls; 2) Cisplatin group-cisplatin induced acute renal failure (ARF) plus vehicle treatment; 3) Cisplatin+nordihydroguaiaretic acid (NDGA) group-cisplatin induced ARF plus 5-lipoxygenase inhibitor treatment; 4) Cisplatin+erythropoietin (EPO) group-cisplatin induced ARF plus erythrop...

  8. Expression and significance of VEGF, CD34, Ki-67 and p21 in pterygium

    Directory of Open Access Journals (Sweden)

    Li-Bo Wang

    2014-07-01

    Full Text Available AIM: To investigate the expression of VEGF, CD34, Ki-67 and p21 in pterygium as well as the correlation between their expression and clinical pathological characteristics; explore its pathogenesis. METHODS: Immunohistochemical S-P staining method was adopted in detecting the expression of VEGF, CD34, Ki-67 and p21 in 62 cases of pterygia and 20 cases of normal conjunctival tissues. Relationship between these markers and clinical pathological characteristics was analyzed. RESULTS:(1The positive expression of VEGF, CD34, Ki-67 and p21 in 62 cases of pterygia was 74.2%(46/62, 77.4%(48/62, 66.1%(41/62and 40.3%(25/62respectively. The differences were statistically significant compared with normal conjunctival tissues(PPP>0.05; the expression of Ki-67 was correlated with clinical stages(PP>0.05; the expression of p21 was correlated with clinical stages and pterygium characters(PP>0.05.(3Spearman correlation showed that there was a positive correlation between VEGF and Ki-67(r=0.279, Pr=0.299, Pr=-0.267, PP>0.05.CONCLUSION:(1Overexpression of VEGF, Ki-67, CD34 and low expression of p21 suggest that these markers are concerned with the development and progression of pterygium.(2Expression of VEGF and CD34 increases along with the increase of clinical types and stages, expression of Ki-67 increases along with the increase of clinical stages, and expression of p21 decreases along with the improvement of clinical types or stages; they suggest that these markers may play important roles in the development and recurrence of pterygium.(3There is positive correlation between VEGF and Ki-67, VEGF and CD34 as well as negative correlation between VEGF and p21. They suggest that there may be synergistic action between two factors during the development and progression of pterygium.

  9. A nanobody directed to a functional epitope on VEGF, as a novel strategy for cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Farajpour, Zahra [Department of Pharmaceutical Biotechnology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Rahbarizadeh, Fatemeh, E-mail: rahbarif@modares.ac.ir [Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Kazemi, Bahram [Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ahmadvand, Davoud [School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2014-03-28

    Highlights: • A novel nanobody directed to antigenic regions on VEGF was identified. • Our nanobody was successfully purified. • Our nanobody significantly inhibited VEGF-induced proliferation of HUVECs in a dose dependent manner. - Abstract: Compelling evidence suggests that vascular endothelial growth factor (VEGF), due to its essential role in angiogenesis, is a critical target for cancer treatment. Neutralizing monoclonal antibodies against VEGF are important class of drugs used in cancer therapy. However, the cost of production, large size, and immunogenicity are main drawbacks of conventional monoclonal therapy. Nanobodies are the smallest antigen-binding antibody fragments, which occur naturally in camelidae. Because of their remarkable features, we decided to use an immune library of nanobody to direct phage display to recognition of novel functional epitopes on VEGF. Four rounds of selection were performed and six phage-displayed nanobodies were obtained from an immune phage library. The most reactive clone in whole-cell ELISA experiments, was purified and assessed in proliferation inhibition assay. Purified ZFR-5 not only blocked interaction of VEGF with its receptor in cell ELISA experiments, but also was able to significantly inhibit proliferation response of human umbilical vein endothelial cells to VEGF in a dose-dependent manner. Taken together, our study demonstrates that by using whole-cell ELISA experiments, nanobodies against antigenic regions included in interaction of VEGF with its receptors can be directed. Because of unique and intrinsic properties of a nanobody and the ability of selected nanobody for blocking the epitope that is important for biological function of VEGF, it represents novel potential drug candidate.

  10. VEGF and Id-1 in pancreatic adenocarcinoma: prognostic significance and impact on angiogenesis.

    Science.gov (United States)

    Georgiadou, D; Sergentanis, T N; Sakellariou, S; Filippakis, G M; Zagouri, F; Vlachodimitropoulos, D; Psaltopoulou, T; Lazaris, A C; Patsouris, E; Zografos, G C

    2014-10-01

    The significance of vascular endothelial growth factor (VEGF) and inhibitor of differentiation/DNA synthesis (Id-1) in tumor neoangiogenesis and tumor progression in pancreatic ductal adenocarcinoma (PDAC) is still unclear. Given the central role of VEGF in cancer angiogenesis and the inconclusive results on Id-1 expression in PDAC, it is of great interest to investigate whether Id-1 and VEGF expression are associated with angiogenesis and prognosis in PDAC. Paraffin-embedded specimens from 60 consecutive patients with PDAC were immunostained for VEGF, Id-1 and CD34 and staining quantification was assessed by Image analysis system. The correlations among the expression of individual angiogenic factors and microvessel density (MVD), clinicopathologic features and clinical prognosis were analyzed. Id-1 and VEGF Positive Activity Indices (PAIs) closely correlated with each other. MVD positively correlated with both Id-1 and VEGF expression. More advanced T and N status correlated with more intense expression of Id-1, VEGF and higher MVD. With regard to prognostic significance higher Id-1 PAI (adjusted HR = 1.69, 95%CI: 1.10-2.59, p = 0.017), higher VEGF PAI (adjusted HR = 2.66, 95%CI: 1.09-6.50, p = 0.032), and MVD (adjusted HR = 1.55, 95%CI: 1.27-1.88, p < 0.001) were associated with poorer survival. VEGF and Id-1 overexpression were found to be associated with high MVD and emerged as adverse prognostic factors in terms of patient survival in PDAC. The potential of selective anti-angiogenic targeting therapy for pancreatic malignancies should prompt further validation of the present findings in studies encompassing larger samples and more elaborate techniques. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Vascular endothelial growth factor (VEGF) expression in the lung in toxic septic shock.

    Science.gov (United States)

    Manoilescu, Irina; Teleman, S; Cojocaru, Elena; Mihăilă, Doina; Plămădeală, P

    2011-01-01

    The need for reasoning with medical evidence the different types of shock, especially when there are medical and legal implications, has determined the search of biological markers of the shock. In the case of toxic septic shock, the most important markers to be used are: the cytokines, the tumor necrosis factor-alpha (TNF-alpha) and interleukin 6 (IL-6), procalcitonin, lactoferin and the vascular endothelial growth factor (VEGF). VEGF has an essential role in angiogenesis and vascular permeability. In our study group, we included 30 cases of different types of shock in which we studied the VEGF expression in the lungs. We added also 10 fragments of lung as control group. According to the etiology, the 30 cases of shock were: 15 with a toxic septic shock and 15 with a hemorrhagic shock. In all these cases we used the classical Hematoxylin and Eosin staining method and the immunohistochemical reactions for VEGF-A. Statistical analysis was performed using SPSS 13.0. The VEGF expression was decreased in all the cases of toxic septic shock, in the endothelium and also in the alveolar epithelium, compared to a high level of expression in other cases of shock and in the control lung. These data allow us to appreciate that VEGF has a different expression in different types of shock and in the normal lung. We observed a statistically significant difference between VEGF expression in toxic septic shock and hemorrhagic shock (p=0.000001). There is a similarity of VEGF expression between hemorrhagic shock and the control lungs (p=0.00001). An obviously low VEGF expression in the toxic septic shock represents a useful biological marker in the forensic medical cases.

  12. Patient Blood Management in Major Orthopedic Surgery: Less Erythropoietin and More Iron?

    Science.gov (United States)

    Rineau, Emmanuel; Stoyanov, Alexandra; Samson, Emmanuel; Hubert, Laurent; Lasocki, Sigismond

    2017-11-01

    Erythropoietin (EPO) is proposed preoperatively to reduce blood transfusion in anemic patients (hemoglobin < 13 g/dL) scheduled for a major orthopedic surgery. New intravenous iron formulations allow infusion of higher doses, increasing EPO response. In that context, we evaluated in a before-after study (n = 62 and 65 patients for each period) a new EPO administration protocol (2 injections 4 and 3 weeks before surgery, and a third if hemoglobin <13 g/dL instead of <15 g/dL 2 weeks before surgery). After this protocol implementation, the mean (standard deviation) number of EPO injections decreased from 2.8 (0.5) to 2.2 (0.4)/patient (P < .0001) without changing transfusion rates (3% in the 2 periods).

  13. Erythropoietin may reduce the risk of germ cell loss in boys with cryptorchidism

    DEFF Research Database (Denmark)

    Cortes, Dina; Visfeldt, J; Thorup, J M

    2001-01-01

    In boys with cryptorchidism older than 2 years a testicular biopsy at time of orchiopexy shows lack of germ cells in 10-40% of the cases. The number of spermatogonia per tubule is prognostic for subsequent fertility potential. A biopsy without germ cells is associated with 33-100% risk...... of infertility. In order to increase the number of germ cells, and thereby the fertility potential, additional hormonal therapy has been attempted before surgery. In a study, small doses of the gonadotropin-releasing hormone analogue buserelin before orchiopexy caused higher values. Others have found...... that hormonal treatment with human chorionic gonadotropin or gonadotropin releasing hormone analogue may harm the germ cells in cryptorchidism. The aim of the study is to demonstrate that additional hormonal therapy with erythropoietin has a positive effect on the number of germ cells....

  14. Effects of erythropoietin on depressive symptoms and neurocognitive deficits in depression and bipolar disorder

    DEFF Research Database (Denmark)

    Miskowiak, Kamilla W; Vinberg, Maj; Harmer, Catherine J

    2010-01-01

    BACKGROUND: Depression and bipolar disorder are associated with reduced neural plasticity and deficits in memory, attention and executive function. Drug treatments for these affective disorders have insufficient clinical effects in a large group and fail to reverse cognitive deficits. There is thus...... a need for more effective treatments which aid cognitive function. Erythropoietin (Epo) is involved in neuroplasticity and is a candidate for future treatment of affective disorders. The investigators have demonstrated that a single dose of Epo improves cognitive function and reduces neurocognitive...... processing of negative emotional information in healthy and depressed individuals similar to effects seen with conventional antidepressants. The current study adds to the previous findings by investigating whether repeated Epo administration has antidepressant effects in patients with treatment resistant...

  15. Prolonged administration of recombinant human erythropoietin increases submaximal performance more than maximal aerobic capacity

    DEFF Research Database (Denmark)

    Thomsen, J J; Rentsch, R L; Robach, P

    2007-01-01

    The effects of recombinant human erythropoietin (rHuEpo) treatment on aerobic power (VO2max) are well documented, but little is known about the effects of rHuEpo on submaximal exercise performance. The present study investigated the effect on performance (ergometer cycling, 20-30 min at 80......HuEpo treatment VO2max increased (PVO2max) was increased by 54.0 and 54.3% (P... week 11), TTE was decreased by 26.8% as compared to pre rHuEpo administration. In conclusion, in healthy non-athlete subjects rHuEpo administration prolongs submaximal exercise performance by about 54% independently of the approximately 12% increase in VO2max....

  16. Recombinant human erythropoietin increases survival and reduces neuronal apoptosis in a murine model of cerebral malaria

    DEFF Research Database (Denmark)

    Wiese, Lothar; Hempel, Casper; Penkowa, Milena

    2008-01-01

    BACKGROUND: Cerebral malaria (CM) is an acute encephalopathy with increased pro-inflammatory cytokines, sequestration of parasitized erythrocytes and localized ischaemia. In children CM induces cognitive impairment in about 10% of the survivors. Erythropoietin (Epo) has - besides of its well known...... with recombinant human Epo (rhEpo; 50-5000 U/kg/OD, i.p.) at different time points. The effect on survival was measured. Brain pathology was investigated by TUNEL (Terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP)-digoxigenin nick end labelling), as a marker of apoptosis. Gene...... expression in brain tissue was measured by real time PCR. RESULTS: Treatment with rhEpo increased survival in mice with CM in a dose- and time-dependent manner and reduced apoptotic cell death of neurons as well as the expression of pro-inflammatory cytokines in the brain. This neuroprotective effect...

  17. PRELIMINARY MODELING OF AN INDUSTRIAL RECOMBINANT HUMAN ERYTHROPOIETIN PURIFICATION PROCESS BY ARTIFICIAL NEURAL NETWORKS

    Directory of Open Access Journals (Sweden)

    R. H. R. Garcel1

    2015-09-01

    Full Text Available AbstractIn the present study a preliminary neural network modelling to improve our understanding of Recombinant Human Erythropoietin purification process in a plant was explored. A three layer feed-forward back propagation neural network was constructed for predicting the efficiency of the purification section comprising four chromatographic steps as a function of eleven operational variables. The neural network model performed very well in the training and validation phases. Using the connection weight method the predictor variables were ranked based on their estimated explanatory importance in the neural network and five input variables were found to be predominant over the others. These results provided useful information showing that the first chromatographic step and the third chromatographic step are decisive to achieve high efficiencies in the purification section, thus enriching the control strategy of the plant.

  18. CNS hypoxia is more pronounced in murine cerebral than noncerebral malaria and is reversed by erythropoietin

    DEFF Research Database (Denmark)

    Hempel, Casper; Combes, Valery; Hunt, Nicholas Henry

    2011-01-01

    observed in mice without CM, and hypoxia seemed to be confined to neuronal cell somas. PARP-1-deficient mice were not protected against CM, which argues against a role for cytopathic hypoxia. Erythropoietin therapy reversed the development of CM and substantially reduced the degree of neural hypoxia......Cerebral malaria (CM) is associated with high mortality and risk of sequelae, and development of adjunct therapies is hampered by limited knowledge of its pathogenesis. To assess the role of cerebral hypoxia, we used two experimental models of CM, Plasmodium berghei ANKA in CBA and C57BL/6 mice....... These findings demonstrate cerebral hypoxia in malaria, strongly associated with cerebral dysfunction and a possible target for adjunctive therapy....

  19. Effects of erythropoietin on memory-relevant neurocircuitry activity and recall in mood disorders

    DEFF Research Database (Denmark)

    Miskowiak, K W; Macoveanu, J; Vinberg, M

    2016-01-01

    OBJECTIVE: Erythropoietin (EPO) improves verbal memory and reverses subfield hippocampal volume loss across depression and bipolar disorder (BD). This study aimed to investigate with functional magnetic resonance imaging (fMRI) whether these effects were accompanied by functional changes in memory......MRI at 3T, mood ratings, and blood tests at baseline and week 14. During fMRI, participants performed a picture encoding task followed by postscan recall. RESULTS: Sixty-two patients had complete data (EPO: N = 32, saline: N = 30). EPO improved picture recall and increased encoding-related activity...... cohort. The effects of EPO were not correlated with change in mood, red blood cells, blood pressure, or medication. CONCLUSION: The findings highlight enhanced encoding-related dlPFC and temporo-parietal activity as key neuronal underpinnings of EPO-associated memory improvement....

  20. Neural correlates of improved executive function following erythropoietin treatment in mood disorders

    DEFF Research Database (Denmark)

    Miskowiak, K. W.; Vinberg, M.; Glerup, L.

    2016-01-01

    BACKGROUND: Cognitive dysfunction in depression and bipolar disorder (BD) is insufficiently targeted by available treatments. Erythropoietin (EPO) increases neuroplasticity and may improve cognition in mood disorders, but the neuronal mechanisms of these effects are unknown. This functional...... of EPO (40 000 IU) (N = 30) or saline (N = 26) in a double-blind, parallel-group design. Patients underwent fMRI, mood ratings and blood tests at baseline and week 14. During fMRI patients performed an n-back WM task. RESULTS: EPO improved WM accuracy compared with saline (p = 0.045). Whole......, baseline to follow-up changes in WM performance correlated positively with changes in WM-related SFG activity and negatively with hippocampal response (r = 0.28-0.30, p mood or red blood cells (p ⩾0.08). CONCLUSIONS: The present findings...

  1. Erythropoietin deficiency in acute crescentic glomerulonephritis and in total bilateral renal cortical necrosis

    DEFF Research Database (Denmark)

    Thaysen, J H; Nielsen, O J; Brandi, L

    1991-01-01

    Six patients with acute renal failure, in five cases due to acute crescentic glomerulonephritis and in one case due to total bilateral renal cortical necrosis, were studied. All had serum erythropoietin (EPO) concentrations in the normal range, despite a relatively severe anaemia. Half...... treated with rhEPO (Eprex). In marked contrast to untreated controls, both patients responded with vigorous reticulocytosis and normalization of haemoglobin levels while they were still in severe renal failure. These results are similar to our previous findings in patients with acute renal failure due...... of EPO is not only a permanent and irreversible feature of severe chronic renal failure, but that it is also present, usually in a transient and reversible form, in different types of acute renal failure....

  2. Satellite cell response to erythropoietin treatment and endurance training in healthy young men

    DEFF Research Database (Denmark)

    Hoedt, Andrea; Christensen, Britt; Nellemann, Birgitte

    2016-01-01

    KEY POINT: Erythropoietin (Epo) treatment may induce myogenic differentiation factor (MyoD) expression and prevent apoptosis in satellite cells (SCs) in murine and in vitro models. Endurance training stimulates SC proliferation in vivo in murine and human skeletal muscle. In the present study, we......-receptor interaction. Moreover, endurance training, but not Epo treatment, increases the SC content in type II myofibres, as well as the content of MyoD(+) SCs. Collectively, our results suggest that Epo treatment can regulate human SCs in vivo, supported by Epo receptor mRNA expression in human SCs. In effect, long......-term Epo treatment during disease conditions involving anaemia may impact SCs and warrants further investigation. Satellite cell (SC) proliferation is observed following erythropoitin treatment in vitro in murine myoblasts and endurance training in vivo in human skeletal muscle. The present study aimed...

  3. Common variants of the genes encoding erythropoietin and its receptor modulate cognitive performance in schizophrenia

    DEFF Research Database (Denmark)

    Kästner, Anne; Grube, Sabrina; El-Kordi, Ahmed

    2012-01-01

    Erythropoietin (EPO) improves cognitive performance in clinical studies and rodent experiments. We hypothesized that an intrinsic role of EPO for cognition exists, with particular relevance in situations of cognitive decline, which is reflected by associations of EPO and EPO receptor (EPOR......) genotypes with cognitive functions. To prove this hypothesis, schizophrenic patients (N > 1000) were genotyped for 5' upstream-located gene variants, EPO SNP rs1617640 (T/G) and EPORSTR(GA)(n). Associations of these variants were obtained for cognitive processing speed, fine motor skills and short......-term memory readouts, with one particular combination of genotypes superior to all others (p 800), these associations were confirmed. A matching preclinical study with mice demonstrated cognitive processing speed and memory enhanced upon transgenic...

  4. Erythropoietin levels in patients with sleep apnea: a meta-analysis.

    Science.gov (United States)

    Zhang, Xiao-Bin; Zeng, Yi-Ming; Zeng, Hui-Qing; Zhang, Hua-Ping; Wang, Hui-Ling

    2017-06-01

    Currently available data regarding the blood levels of erythropoietin (EPO) in sleep apnea (SA) patients are contradictory. The aim of the present meta-analysis was to evaluate the EPO levels in SA patients via quantitative analysis. A systematic search of Pubmed, Embase, and Web of Science were performed. EPO levels in SA group and control group were extracted from each eligible study. Weight mean difference (WMD) or Standard mean difference (SMD) with 95% confidence interval (CI) was calculated by using fixed-effects or random effect model analysis according to the degree of heterogeneity between studies. A total of 9 studies involving 407 participants were enrolled. The results indicated that EPO levels in SA group were significantly higher than that in control group (SMD 0.61, 95% CI 0.11-1.11, p = 0.016). Significantly higher EPO levels were found in patients with body mass index analysis (both p analysis.

  5. EG-VEGF Maintenance Over Early Gestation to Develop a Pregnancy-Induced Hypertensive Animal Model.

    Science.gov (United States)

    Reynaud, Déborah; Sergent, Frédéric; Nahed, Roland Abi; Brouillet, Sophie; Benharouga, Mohamed; Alfaidy, Nadia

    2018-01-01

    During the last decade, multiple animal models have been developed to mimic hallmarks of pregnancy-induced hypertension (PIH) diseases, which include gestational hypertension, preeclampsia (PE), or eclampsia. Converging in vitro, ex vivo, and clinical studies from our group strongly suggested the potential involvement of the new angiogenic factor EG-VEGF (endocrine gland-derived-VEGF) in the development of PIH. Here, we described the protocol that served to demonstrate that maintenance of EG-VEGF production over 11.5 days post coitus (dpc) in the gravid mice caused the development of PIH. The developed model exhibited most hallmarks of preeclampsia.

  6. Inhibition of VEGF: a novel mechanism to control angiogenesis by Withania somnifera's key metabolite Withaferin A.

    Science.gov (United States)

    Saha, Sanjib; Islam, Md Khirul; Shilpi, Jamil A; Hasan, Shihab

    2013-01-01

    Angiogenesis, or new blood vessel formation from existing one, plays both beneficial and detrimental roles in living organisms in different aspects. Vascular endothelial growth factor (VEGF), a signal protein, well established as key regulator of vasculogenesis and angiogenesis. VEGF ensures oxygen supply to the tissues when blood supply is not adequate, or tissue environment is in hypoxic condition. Limited expression of VEGF is necessary, but if it is over expressed, then it can lead to serious disease like cancer. Cancers that have ability to express VEGF are more efficient to grow and metastasize because solid cancers cannot grow larger than a limited size without adequate blood and oxygen supply. Anti-VEGF drugs are already available in the market to control angiogenesis, but they are often associated with severe side-effects like fetal bleeding and proteinuria in the large number of patients. To avoid such side-effects, new insight is required to find potential compounds as anti-VEGF from natural sources. In the present investigation, molecular docking studies were carried out to find the potentiality of Withaferin A, a key metabolite of Withania somnifera, as an inhibitor of VEGF. Molecular Docking studies were performed in DockingServer and SwissDock. Bevacizumab, a commercial anti-VEGF drug, was used as reference to compare the activity of Withaferin A. X-ray crystallographic structure of VEGF, was retrieved from Protein Data Bank (PDB), and used as drug target protein. Structure of Withaferin A and Bevacizumab was obtained from PubChem and ZINC databases. Molecular visualization was performed using UCSF Chimera. Withaferin A showed favorable binding with VEGF with low binding energy in comparison to Bevacizumab. Molecular Docking studies also revealed potential protein-ligand interactions for both Withaferin A and Bevacizumab. Conclusively our results strongly suggest that Withaferin A is a potent anti-VEGF agent as ascertained by its potential

  7. Serum VEGF levels as predictive marker of bisphosphonate-related osteonecrosis of the jaw

    Directory of Open Access Journals (Sweden)

    Vincenzi Bruno

    2012-09-01

    Full Text Available Abstract Recent studies have been reported that angiogenesis suppression may play a role in developing bisphosphonate-related osteonecrosis of the jaw (B-ONJ. According to these evidence we evaluated the role of VEGF as predictive marker of B-ONJ onset. Of the 81 patients, 6 developed B-ONJ following bisphosphonate treatment. These patients showed a strongest decrease in VEGF circulating levels at day 7 and at day 21 after the first administration. These data demonstrated for the first time that the anti-angiogenic properties of bisphosphonates are directly linked to B-ONJ pathogenesis and serum VEGF levels could represent an effective early predictive marker.

  8. Contraction induced secretion of VEGF from skeletal muscle cells is mediated by adenosine

    DEFF Research Database (Denmark)

    Høier, Birgitte; Olsen, Karina; Nyberg, Michael Permin

    2010-01-01

    The role of adenosine and contraction for secretion of VEGF in skeletal muscle was investigated in human subjects and rat primary skeletal muscle cells. Microdialysis probes were inserted into the thigh muscle of seven male subjects and dialysate was collected at rest, during infusion of adenosine...... and during knee extensor exercise. The dialysate was analyzed for content of VEGF protein and adenosine. The mechanism of VEGF secretion from muscle cells in culture was examined in resting and electro stimulated cells, and in response to the adenosine analogue NECA, and the adenosine A(2A) receptor specific...... infusion enhanced (Pmuscle cells, NECA...

  9. Assessing the instability of the isoelectric focusing patterns of erythropoietin in urine.

    Science.gov (United States)

    Belalcazar, Viviana; Gutiérrez Gallego, Ricardo; Llop, Esther; Segura, Jordi; Pascual, José Antonio

    2006-11-01

    IEF can be used to differentiate human urinary erythropoietin (uEPO), recombinant human erythropoietin or epoetin (rEPO) and darbepoetin (novel erythropoiesis stimulating protein (NESP)). This is the basis of the method currently used to detect misuse of rEPO and NESP by elite athletes. Recently, an unknown activity has been attributed to some urine samples (denominated 'unstable' urine by the World Anti-Doping Agency; WADA). This activity has shown to give rise to artefactual profiles for both rEPO and NESP when incubated with such urine and, thus, raised concerns with respect to doping control. We have evaluated which charges produce the characteristic IEF profiles of uEPO, rEPO and NESP and how these profiles respond to distinct enzymatic reactions. From sialidase digestions it became evident that only uEPO contains charges different from sialic acid, and a comparison of all substances after complete de-N-glycosylation localized these charges in the carbohydrate moiety. Partial desialylation, or digestion with arylsulfatase from Helix pomatia yielded profiles for recombinants species similar to those observed for unstable urine samples. The contributions from our studies to the anti-doping problem include: (i) protocols that may corroborate the potential misuse of rEPO or NESP based on the particular enzymatic activity of an arylsulfatase preparation, or a broad-specificity sialidase; (ii) assurance that the instability observed in some urine samples may only result from false-negatives, but not from false-positive testing; and (iii) a simple remedy to prevent an unstable urine from altering the IEF profile by adding selective competitive substrates.

  10. The role of erythropoietin stimulating agents in anemic patients with heart failure: solved and unresolved questions

    Directory of Open Access Journals (Sweden)

    Palazzuoli A

    2014-08-01

    Full Text Available Alberto Palazzuoli, Gaetano Ruocco, Marco Pellegrini, Carmelo De Gori, Gabriele Del Castillo, Nicola Giordano, Ranuccio NutiDepartment of Internal Medicine and Metabolic Diseases, Cardiology Section, Le Scotte Hospital, University of Siena, Siena, ItalyAbstract: Anemia is a common finding in congestive heart failure (CHF and is associated with an increased mortality and morbidity. Several conditions can cause depression of erythroid progenitor cells: reduction of iron absorption and reuptake, decreased bone marrow activity, reduced endogenous erythropoietin production, and chronic inflammatory state. Anemia’s etiology in CHF is complex and partially understood; it involves several systems including impaired hemodynamic condition, reduced kidney and bone perfusion, increased inflammatory activity, and neurohormonal overdrive. The use of erythropoiesis stimulating agents (ESAs such as erythropoietin and its derivatives is recently debated; the last interventional trial seems to demonstrate a neutral or negative effect in the active arm with darbepoetin treatment. The current data is opposite to many single blind studies and previous meta-analysis showing an improvement in quality of life, New York Heart Association class, and exercise tolerance using ESA therapy. These contrasting data raise several concerns regarding the target of hemoglobin levels needing intervention, the exact anemia classification and categorization, and the standardization of hematocrit cutoffs. Some cardiac and systemic conditions (ie, hypertension, atrial fibrillation, prothrombotic status may predispose to adverse events, and ESA administration should be avoided. To prevent the negative effects, high-dosage and chronic administration should be avoided. Clarification of these items could probably identify patients that may benefit from additional iron or ESA treatment. In this review, we discuss the interventional trials made in anemic heart failure patients, the

  11. Erythropoietin receptor expression is a potential prognostic factor in human lung adenocarcinoma.

    Directory of Open Access Journals (Sweden)

    Anita Rózsás

    Full Text Available Recombinant human erythropoietins (rHuEPOs are used to treat cancer-related anemia. Recent preclinical studies and clinical trials, however, have raised concerns about the potential tumor-promoting effects of these drugs. Because the clinical significance of erythropoietin receptor (EPOR signaling in human non-small cell lung cancer (NSCLC also remains controversial, our aim was to study whether EPO treatment modifies tumor growth and if EPOR expression has an impact on the clinical behavior of this malignancy. A total of 43 patients with stage III-IV adenocarcinoma (ADC and complete clinicopathological data were included. EPOR expression in human ADC samples and cell lines was measured by quantitative real-time polymerase chain reaction. Effects of exogenous rHuEPOα were studied on human lung ADC cell lines in vitro. In vivo growth of human ADC xenografts treated with rHuEPOα with or without chemotherapy was also assessed. In vivo tumor and endothelial cell (EC proliferation was determined by 5-bromo-2'-deoxy-uridine (BrdU incorporation and immunofluorescent labeling. Although EPOR mRNA was expressed in all of the three investigated ADC cell lines, rHuEPOα treatment (either alone or in combination with gemcitabine did not alter ADC cell proliferation in vitro. However, rHuEPOα significantly decreased tumor cell proliferation and growth of human H1975 lung ADC xenografts. At the same time, rHuEPOα treatment of H1975 tumors resulted in accelerated tumor endothelial cell proliferation. Moreover, in patients with advanced stage lung ADC, high intratumoral EPOR mRNA levels were associated with significantly increased overall survival. This study reveals high EPOR level as a potential novel positive prognostic marker in human lung ADC.

  12. Recombinant human erythropoietin therapy for anemic cancer patients receiving cisplatin chemotherapy.

    Science.gov (United States)

    Henry, D H; Brooks, B J; Case, D C; Fishkin, E; Jacobson, R; Keller, A M; Kugler, J; Moore, J; Silver, R T; Storniolo, A M; Abels, R I; Gordon, D S; Nelson, R; Larholt, K; Bryant, E; Rudnick, S

    1995-01-01

    To assess whether the administration of recombinant human erythropoietin (r-HuEPO) would increase the hematocrit, reduce the requirement for transfusion, and improve the quality of life in anemic cancer patients receiving myelosuppressive, cisplatin-based chemotherapy. One hundred thirty-two anemic cancer patients receiving cyclic, cisplatin-containing, myelosuppressive chemotherapy were evaluated. Patients received either r-HuEPO (150 U/kg) or placebo, subcutaneously, three times a week for 3 months. Responses were assessed by measuring changes in hemoglobin/hematocrit, transfusion requirement, and quality of life. The mean hematocrit increased by 6.0 percentage points in the r-HuEPO group versus 1.3 in the placebo group. A decrease in transfusion requirement did not reach significance over all 3 months, but there was a significant reduction in the percentage of patients transfused in the second and third months (27% r-HuEPO vs. 56% placebo) and a trend toward reduction in the mean total number of units transfused (1.20 units r-HuEPO vs. 2.02 units placebo), suggesting a lag of 1 month before r-HuEPO can affect the transfusion requirement. Pretreatment serum erythropoietin levels were lower in responders than in nonresponders (73.5 IU/L and 86.3 IU/L means, respectively). However, the magnitude of this difference was not helpful in defining which patients were likely to respond. There was a significant improvement in overall quality of life between the two treatment arms in favor of the r-HuEPO-treated group. There were no significant adverse effects associated with r-HuEPO. r-HuEPO is safe and can cause a significant improvement in the hematocrit and quality of life of anemic cancer patients receiving myelosuppressive, cisplatin-based chemotherapy. After 1 month of r-HuEPO, there is also a reduction in transfusion requirement.

  13. Recombinant human erythropoietin reduces plasminogen activator inhibitor and ameliorates pro-inflammatory responses following trauma

    Directory of Open Access Journals (Sweden)

    M Mojtahedzadeh

    2011-05-01

    Full Text Available "n  "n Background and the purpose of the study: Besides its hematopoietic effects, erythropoietin (EPO by mobilization of iron and modulation of some inflammatory cytokines has antioxidant and anti-inflammatory properties. The purpose of this study was to evaluate these effects of erythropoietin and its impact on organ function in traumatized patients. "n Methods: Twenty-six ICU-admitted traumatized patients within 24 hrs after trauma were randomly assigned to the EPO (received EPO, 300 units/Kg/day and Control (not received EPO groups. The inflammatory biomarkers including Tumor Necrosis Factor alpha (TNF-α, Interleukin 1 (IL-1, Plasminogen Activator Inhibitor 1 (PAI-1 and Nitrotyrosine were recorded at the admission, 3, 6 and 9 days thereafter. Acute Physiology and Chronic Health Evaluation (APACHE II and Sequential Organ Failure Assessment (SOFA scores were also recorded. "n Results: Among 12 patients (EPO group TNF-α level at the day of 9 (P=0.046, and within EPO group at the days of 3 (P=0.026 ameliorate, 6 (P=0.016, and 9 (P=0.052 were significantly lowered. Level of IL-1 and PAI-1 decreased significantly at days of 3, 6 and 9 post intervention. Also there were significant differences between two groups in the SOFA score during three measured time intervals (the first, third and seventh days. "n Conclusion: From the results of this study it seems that injection of erythrocyte stimulating agent is well tolerated and inhibits the inflammatory response and oxidative stress following trauma.

  14. Association of I/D angiotensin-converting enzyme genotype with erythropoietin stimulation in kidney failure

    Directory of Open Access Journals (Sweden)

    Savin Marina

    2017-01-01

    Full Text Available Angiotensin-converting enzyme (ACE-gene polymorphism is a possible predisposing factor of erythropoietin response under hypoxic conditions. However, it is not completely clear whether the ACE insertion/deletion (I/D genotype has an impact on anemia in patients with permanent kidney failure. A 9-month prospective trial was conducted on 53 patients on hemodialysis aimed at determining the beneficial effect of oral vs intravenous iron in anemia management with recombinant human erythropoietin (rHuEpo, and identifying a possible association of the ACE gene I/D polymorphism with the response to rHuEpo. Patients were randomly allocated to receive 50-100 mg daily of ferrous gluconate orally (N=26 or intravenously every two weeks (N=27, together with rHuEpo-beta (200 IU/kg subcutaneously, to achieve a hemoglobin increase to 105 g/L; subsequently the rHuEpo dose was adjusted at one or two week intervals. In 34 patients who regularly received ACE-inhibitor (ACEi medication, genotyping for ACE-gene I/D polymorphism was performed using PCR, gel analysis and appropriate restriction digestion. After prolonged rHuEpo treatment, 24.5% of patients attained the targeted 9th-month hemoglobin concentration (105 g/L. Of these, 6/26 of patients received elemental iron orally and 7/27 received it intravenously. We observed an association between homozygous DD (deletion of the ACE gene and a remarkable early increase in blood hemoglobin (p=0.028, erythrocyte count (p=0.020 and hematocrit (p=0.043 after reduction of the dose of rHuEpo (F=3.95; p=0.029, irrespective of the iron repletion mode (p=0.960. This is the first report on DD genotype as a linkage marker for the optimization of rHuEpo dose for anemia management in hemodialysis patients.

  15. Encapsulated VEGF-secreting cells enhance proliferation of neuronal progenitors in the hippocampus of AβPP/Ps1 mice.

    Science.gov (United States)

    Antequera, Desiree; Portero, Aitziber; Bolos, Marta; Orive, Gorka; Hernández, Rosa M Rm A; Pedraz, José Luis; Carro, Eva

    2012-01-01

    Vascular endothelial growth factor (VEGF) promotes neurogenesis in the adult hippocampus, but the way in which this process occurs in the Alzheimer's disease (AD) brain is still unknown. We examined the proliferation of neuronal precursors with an ex vivo approach, using encapsulated VEGF secreting cells, in AβPP/PS1 mice, a mouse model of AD. Overexpression of VEGF and VEGF receptor flk-1 was observed in the cerebral cortex from VEGF microcapsules-treated AβPP/PS1 mice at 1, 3 and 6 months after VEGF-microcapsule implantation. Stereological counting of 5-bromodeoxyuridine positive cells revealed that encapsulated VEGF secreting cells significantly enhanced cellular proliferation in the hippocampal dentate gyrus (DG). The number of neuronal precursors in VEGF microcapsules-treated AβPP/PS1 mice was also greater, and this effect remains after 6 months. We also confirmed that encapsulated VEGF secreting cells also stimulated angiogenesis in the cerebral cortex and hippocampal dentate gyrus. In addition, we found that VEGF-microcapsule treatment was associated with a depressed expression and activity of acetylcholinesterase in the hippocampus of AβPP/PS1 mice, a similar pattern as first-line medications for the treatment of AD. We conclude that stereologically-implanted VEGF-microcapsules exert an acute and long-standing neurotrophic effects, and could be utilized to improve potential therapies to control the progression of AD.

  16. Vascular endothelial growth factor (VEGF) and the VEGF soluble receptor-1 (sFlt-1) in chorionic villus tissue from Chinese women with early recurrent spontaneous abortion.

    Science.gov (United States)

    Pang, L-H; Li, M-J; Li, M-Q; Yang, D-M; Shi, L

    2011-01-01

    This case-control study explored the relationship between early recurrent spontaneous abortion (RSA) and the expression of two genes: VEGFA, the gene encoding vascular endothelial growth factor (VEGF); and fms-related tyrosine kinase 1 (FLT1), the gene encoding the soluble VEGF receptor-1 (sFlt-1). Women experiencing RSA or undergoing induced abortions in the early stage of normal pregnancy were recruited to the study (n = 30 per group). There were no significant between-group differences in maternal age or duration of pregnancy. The levels of VEGF and sFlt-1 mRNA in chorionic villus tissue samples were examined by quanti tative reverse transcription-polymerase chain reaction. Levels of sFlt-1 and VEGF mRNA in the chorionic villus tissue of women with RSA were significantly higher than levels in the control group. This study demonstrated that there is a relationship between early RSA and VEGF and sFlt-1 levels, suggesting that over-expression of the FLT1 and VEGFA genes may be associated with the pathogenesis of RSA.

  17. Angiotensin II type 1 receptor (AT-1R) expression correlates with VEGF-A and VEGF-D expression in invasive ductal breast cancer.

    Science.gov (United States)

    Jethon, Aleksandra; Pula, Bartosz; Piotrowska, Aleksandra; Wojnar, Andrzej; Rys, Janusz; Dziegiel, Piotr; Podhorska-Okolow, Marzena

    2012-10-01

    Recent studies point to the involvement of angiotensin II (Ang II) receptor type 1 (AT-1R) on processes of metastasing, stimulation of invasiveness and angiogenesis in tumours. In this study, the correlation between intensity of AT-1R expression and expression of lymph- and angiogenesis markers in invasive ductal breast cancers (IDC) was examined. Immunohistochemical studies (IHC) were performed on archival material of 102 IDC cases. Only 28 (27.5%) cases manifested low AT-1R expression while 74 (72.5%) cases demonstrated a moderate or pronounced AT-1R expression. Expression intensity of AT-1R was found to correlate with expressions of VEGF-A (r = 0.26; p = 0.008) and VEGF-D (r = 0.24; p = 0.015). Out of the examined markers of angiogenesis and lymphangiogenesis only the pronounced expression of VEGF-C was found to correlate with patient poor clinical outcome (p = 0.009). The positive correlation between AT-1R and VEGF-A and VEGF-D could point to stimulatory action of Ang II on their expression what might result in augmented lymph- and angiogenesis in IDC.

  18. Systemic and cerebral vascular endothelial growth factor levels increase in murine cerebral malaria along with increased Calpain and caspase activity and can be reduced by erythropoietin treatment

    DEFF Research Database (Denmark)

    Hempel, Casper; Hoyer, Nils; Kildemoes, Anna

    2014-01-01

    The pathogenesis of cerebral malaria (CM) includes compromised microvascular perfusion, increased inflammation, cytoadhesion, and endothelial activation. These events cause blood-brain barrier disruption and neuropathology and associations with the vascular endothelial growth factor (VEGF...... increased levels of VEGF in brain and plasma and decreased plasma levels of soluble VEGF receptor 2. EPO treatment normalized VEGF receptor 2 levels and reduced brain VEGF levels. Hypoxia-inducible factor (HIF)-1α was significantly upregulated whereas cerebral HIF-2α and EPO levels remained unchanged...

  19. Vascular Endothelial Growth Factor (VEGF) Bioavailability Regulates Angiogenesis and Intestinal Stem and Progenitor Cell Proliferation during Postnatal Small Intestinal Development.

    Science.gov (United States)

    Schlieve, Christopher R; Mojica, Salvador Garcia; Holoyda, Kathleen A; Hou, Xiaogang; Fowler, Kathryn L; Grikscheit, Tracy C

    2016-01-01

    Vascular endothelial growth factor (VEGF) is a highly conserved, master regulatory molecule required for endothelial cell proliferation, organization, migration and branching morphogenesis. Podocoryne carnea and drosophila, which lack endothelial cells and a vascular system, express VEGF homologs, indicating potential roles beyond angiogenesis and vasculogenesis. The role of VEGF in the development and homeostasis of the postnatal small intestine is unknown. We hypothesized regulating VEGF bioavailability in the postnatal small intestine would exhibit effects beyond the vasculature and influence epithelial cell stem/progenitor populations. VEGF mutant mice were created that overexpressed VEGF in the brush border of epithelium via the villin promotor following doxycycline treatment. To decrease VEGF bioavailability, sFlt-1 mutant mice were generated that overexpressed the soluble VEGF receptor sFlt-1 upon doxycycline administration in the intestinal epithelium. Mice were analyzed after 21 days of doxycycline administration. Increased VEGF expression was confirmed by RT-qPCR and ELISA in the intestine of the VEGF mutants compared to littermates. The VEGF mutant duodenum demonstrated increased angiogenesis and vascular leak as compared to littermate controls. The VEGF mutant duodenum revealed taller villi and increased Ki-67-positive cells in the transit-amplifying zone with reduced Lgr5 expression. The duodenum of sFlt-1 mutants revealed shorter villi and longer crypts with reduced proliferation in the transit-amplifying zone, reduced expression of Dll1, Bmp4 and VE-cadherin, and increased expression of Sox9 and EphB2. Manipulating VEGF bioavailability leads to profound effects on not only the intestinal vasculature, but epithelial stem and progenitor cells in the intestinal crypt. Elucidation of the crosstalk between VEGF signaling in the vasculature, mesenchyme and epithelial stem/progenitor cell populations may direct future cell therapies for intestinal

  20. Erythropoietin in patients with traumatic brain injury and extracranial injury-A post hoc analysis of the erythropoietin traumatic brain injury trial.

    Science.gov (United States)

    Skrifvars, Markus B; Bailey, Michael; French, Craig; Presneill, Jeffrey; Nichol, Alistair; Little, Lorraine; Duranteau, Jacques; Huet, Olivier; Haddad, Samir; Arabi, Yaseen; McArthur, Colin; Cooper, D James; Bellomo, Rinaldo

    2017-09-01

    Erythropoietin (EPO) may reduce mortality after traumatic brain injury (TBI). Secondary brain injury is exacerbated by multiple trauma, and possibly modifiable by EPO. We hypothesized that EPO decreases mortality more in TBI patients with multiple trauma, than in patients with TBI alone. A post hoc analysis of the EPO-TBI randomized controlled trial conducted in 2009 to 2014. To evaluate the impact of injuries outside the brain, we calculated an extracranial Injury Severity Score (ISS) that included the same components of the ISS, excluding head and face components. We defined multiple trauma as two injured body regions with an Abbreviated Injury Scale (AIS) score of 3 or higher. Cox regression analyses, allowing for potential differential responses per the presence or absence of extracranial injury defined by these injury scores, were used to assess the effect of EPO on time to mortality. Of 603 included patients, the median extracranial ISS was 6 (interquartile range, 1-13) and 258 (43%) had an AIS score of 3 or higher in at least two body regions. On Cox regression, EPO was associated with decreased mortality in patients with greater extracranial ISS (interaction p = 0.048) and weakly associated with differential mortality with multiple trauma (AIS score > 3 or in two regions, interaction p = 0.17). At 6 months in patients with extracranial ISS higher than 6, 10 (6.8%) of 147 EPO-treated patients compared with 26 (17%) of 154 placebo-treated patients died (risk reduction, 10%; 95% confidence interval, 2.9-17%; p = 0.007). In this post hoc analysis, EPO administration was associated with a potential differential improvement in 6-month mortality in TBI patients with more severe extracranial injury. These findings need confirmation in future clinical and experimental studies. Therapeutic study, level III.

  1. Two ligands signal through the Drosophila PDGF/VEGF receptor to ensure proper salivary gland positioning.

    Science.gov (United States)

    Harris, Katherine E; Schnittke, Nikolai; Beckendorf, Steven K

    2007-07-01

    The Drosophila embryonic salivary gland is a migrating tissue that undergoes a stereotypic pattern of migration into the embryo. We demonstrate that the migratory path of the salivary gland requires the PDGF/VEGF pathway. The PDGF/VEGF receptor, Pvr, is strongly expressed in the salivary glands, and Pvr mutations cause abnormal ventral curving of the glands, suggesting that Pvr is involved in gland migration. Although the Pvr ligands, Pvf1 and Pvf2, have distinct expression patterns in the Drosophila embryo, mutations for either one of the ligands result in salivary gland migration defects similar to those seen in embryos that lack Pvr. Rescue experiments indicate that the PDGF/VEGF pathway functions autonomously in the salivary gland. The results of this study demonstrate that the Drosophila PDGF/VEGF pathway is essential for proper positioning of the salivary glands.

  2. [Suppression of VEGF protein expression by arctigenin in oral squamous cell carcinoma].

    Science.gov (United States)

    Pu, Guang-rui; Liu, Fa-yu; Wang, Bo

    2015-08-01

    To observe arctigenin's inhibitory effect on oral squamous cell carcinoma, and explore the possible mechanism. The expression of VEGF in 32 cases of oral squamous cell cancer and 20 adjacent tissue specimen were detected with immunohistochemistry. Human nude mouse transplantation tumor model of oral squamous cell cancer was prepared with HSC-3 cells line. Transplanted tumor growth and VEGF expression in transplanted tumor tissues were assayed after treatment with arctigenin. One-way ANOVA was used for comparison between groups with SPSS 16.0 software package. Compared with the adjacent tissue, immunohistochemical staining score of VEGF was significantly higher (Parctigenin, the growth of oral squamous cell transplanted tumors in nude mouse was inhibited (Parctigenin group (PArctigenin can dose-dependently inhibit the growth of oral squamous cell carcinomas, and this effect may be related to down regulation of VEGF expression.

  3. Anti-VEGF agents in the treatment of diabetic macular edema

    Directory of Open Access Journals (Sweden)

    Vladimir Iosifovich Konenkov

    2013-12-01

    Full Text Available Diabetic macular edema (DME is a common complication associated with the loss of visual acuity in diabetic patients. Intravitreal injections of vascular endothelium growth factor (VEGF inhibitors (anti-VEGF therapy have been proposed recently as a new treatment option for patients with DME. In this review we summarized results of randomized clinical trials of VEGF inhibitors in DME patients. The results indicate that all studied inhibitors (ranibizumab, bevacizumab, pegaptanib and aflibersept reduce the retinal thickness and improve of visual acuity in DME when are used as a monotherapy or in combination with the laser treatment. Optimal course duration and effectiveness predictors of anti-VEGF therapy in DME should be elucidate in the future studies.

  4. EGF Regulation of VEGF: Role in Progression of ErbB2 Overexpressing Mammary Tumors

    National Research Council Canada - National Science Library

    Loureiro, Robyn

    2004-01-01

    .... ErbB2, an epidermal growth factor receptor family member whose overexpression in mammary tumors is correlated with poor patient prognosis, has been previously implicated as a positive modulator of VEGF expression...

  5. Hypoproduction of erythropoietin contributes to anemia in chronic cadmium intoxication: clinical study on Itai-itai disease in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Horiguchi, Hyogo (Dept. of Public Health, Faculty of Medicine, Toyama Medical and Pharmaceutical Univ. (Japan)); Teranishi, Hidetoyo (Dept. of Public Health, Faculty of Medicine, Toyama Medical and Pharmaceutical Univ. (Japan)); Niiya, Kenji (Dept. of Clinical Lab. Medicine, Faculty of Medicine, Toyama Medical and Pharmaceutical Univ. (Japan)); Aoshima, Keiko (Dept. of Public Health, Faculty of Medicine, Toyama Medical and Pharmaceutical Univ. (Japan)); Katoh, Terutaka (Dept. of Public Health, Faculty of Medicine, Toyama Medical and Pharmaceutical Univ. (Japan)); Sakuragawa, Nobuo (Dept. of Clinical Lab. Medicine, Faculty of Medicine, Toyama Medical and Pharmaceutical Univ. (Japan)); Kasuya, Minoru (Dept. of Public Health, Faculty of Medicine, Toyama Medical and Pharmaceutical Univ. (Japan))

    1994-10-01

    Itai-itai disease is a condition caused by longterm exposure of the inhabitants of Toyama prefecture, Japan, to cadmium intoxication. The characteristic clinical features of this disease include renal tubular dysfunction, osteomalacia, and anemia. In order to clarify the pathogenesis of the anemia, the red blood cell count, hemoglobin concentration, hematocrit, serum iron level, total iron-binding capacity, serum ferritin level, serum erythropoietin level, creatinine clearance, fractional excretion of [beta][sub 2]-microglobulin, and bone marrow morphology were determined in ten patients with Itai-itai disease. Low serum iron or ferritin levels were not observed, and bone marrow aspiration did not reveal any specific hematological disorders. A close relationship was observed between the decrease in the hemoglobin level and the progression of renal dysfunction. Low serum erythropoietin levels were detected despite the presence of severe anemia. These results suggest an important role of renal damage in the anemia which develops in Itai-itai disease. (orig.)

  6. Enhancement of musculocutaneous nerve reinnervation after vascular endothelial growth factor (VEGF gene therapy

    Directory of Open Access Journals (Sweden)

    Haninec Pavel

    2012-06-01

    Full Text Available Abstract Background Vascular endothelial growth factor (VEGF is not only a potent angiogenic factor but it also promotes axonal outgrowth and proliferation of Schwann cells. The aim of the present study was to quantitatively assess reinnervation of musculocutaneous nerve (MCN stumps using motor and primary sensory neurons after plasmid phVEGF transfection and end-to-end (ETE or end-to-side (ETS neurorrhaphy. The distal stump of rat transected MCN, was transfected with plasmid phVEGF, plasmid alone or treated with vehiculum and reinnervated following ETE or ETS neurorrhaphy for 2 months. The number of motor and dorsal root ganglia neurons reinnervating the MCN stump was estimated following their retrograde labeling with Fluoro-Ruby and Fluoro-Emerald. Reinnervation of the MCN stumps was assessed based on density, diameter and myelin sheath thickness of regenerated axons, grooming test and the wet weight index of the biceps brachii muscles. Results Immunohistochemical detection under the same conditions revealed increased VEGF in the Schwann cells of the MCN stumps transfected with the plasmid phVEGF, as opposed to control stumps transfected with only the plasmid or treated with vehiculum. The MCN stumps transfected with the plasmid phVEGF were reinnervated by moderately higher numbers of motor and sensory neurons after ETE neurorrhaphy compared with control stumps. However, morphometric quality of myelinated axons, grooming test and the wet weight index were significantly better in the MCN plasmid phVEGF transfected stumps. The ETS neurorrhaphy of the MCN plasmid phVEGF transfected stumps in comparison with control stumps resulted in significant elevation of motor and sensory neurons that reinnervated the MCN. Especially noteworthy was the increased numbers of neurons that sent out collateral sprouts into the MCN stumps. Similarly to ETE neurorrhaphy, phVEGF transfection resulted in significantly higher morphometric quality of myelinated axons

  7. Deleterious effects of endogenous and exogenous testosterone on mesenchymal stem cell VEGF production.

    Science.gov (United States)

    Ray, Rinki; Herring, Christine M; Markel, Troy A; Crisostomo, Paul R; Wang, Meijing; Weil, Brent; Lahm, Tim; Meldrum, Daniel R

    2008-05-01

    Modulating the paracrine effects of bone marrow mesenchymal stem cells (BMSCs) may be important for the treatment of ischemic myocardial tissue. In this regard, endogenous estrogen may enhance BMSC vascular endothelial growth factor (VEGF) production. However, little information exists regarding the effect of testosterone on stem cell function. We hypothesized that 1) endogenous or exogenous estrogen will enhance stem cell production of VEGF and 2) endogenous or exogenous testosterone will inhibit BMSC VEGF production. BMSCs were collected from adult male, female, castrated male, and ovariectomized female rats. One hundred thousand cells were incubated with testosterone (1, 10, or 100 nM) or estrogen (0.15, 1.5, or 15 nM) for 48 h. Cell supernatants were collected, and VEGF was measured by ELISA. BMSCs harvested from castrated males, normal females, and ovariectomized females produced more VEGF compared with normal males. Castration was associated with the highest level (1,018 +/- 98.26 pg/ml) of VEGF production by BMSCs, which was significantly more than that produced by BMSCs harvested from normal male and normal female animals. Exogenous testosterone significantly reduced VEGF production in BMSCs harvested from ovariectomized females in a dose-dependent manner. Exogenous estrogen did not alter BMSC VEGF production. These findings suggest that testosterone may work on BMSCs to decrease protective growth factor production and that effective removal of testosterone's deleterious effects via castration may prove to be beneficial in terms of protective factor production. By manipulating the mechanisms that BMSCs use to produce growth factors, we may be able to engineer stem cells to produce maximum growth factors during therapeutic use.

  8. Genetic variation in VEGF does not contribute significantly to the risk of congenital cardiovascular malformation.

    Science.gov (United States)

    Griffin, Helen R; Hall, Darroch H; Topf, Ana; Eden, James; Stuart, A Graham; Parsons, Jonathan; Peart, Ian; Deanfield, John E; O'Sullivan, John; Babu-Narayan, Sonya V; Gatzoulis, Michael A; Bu'lock, Frances A; Bhattacharya, Shoumo; Bentham, Jamie; Farrall, Martin; Granados Riveron, Javier; Brook, J David; Burn, John; Cordell, Heather J; Goodship, Judith A; Keavney, Bernard

    2009-01-01

    Several previous studies have investigated the role of common promoter variants in the vascular endothelial growth factor (VEGF) gene in causing congenital cardiovascular malformation (CVM). However, results have been discrepant between studies and no study to date has comprehensively characterised variation throughout the gene. We genotyped 771 CVM cases, of whom 595 had the outflow tract malformation Tetralogy of Fallot (TOF), and carried out TDT and case-control analyses using haplotype-tagging SNPs in VEGF. We carried out a meta-analysis of previous case-control or family-based studies that had typed VEGF promoter SNPs, which included an additional 570 CVM cases. To identify rare variants potentially causative of CVM, we carried out mutation screening in all VEGF exons and splice sites in 93 TOF cases. There was no significant effect of any VEGF haplotype-tagging SNP on the risk of CVM in our analyses of 771 probands. When the results of this and all previous studies were combined, there was no significant effect of the VEGF promoter SNPs rs699947 (OR 1.05 [95% CI 0.95-1.17]); rs1570360 (OR 1.17 [95% CI 0.99-1.26]); and rs2010963 (OR 1.04 [95% CI 0.93-1.16]) on the risk of CVM in 1341 cases. Mutation screening of 93 TOF cases revealed no VEGF coding sequence variants and no changes at splice consensus sequences. Genetic variation in VEGF appears to play a small role, if any, in outflow tract CVM susceptibility.

  9. Prognostic importance of VEGF-A haplotype combinations in a stage II colon cancer population

    DEFF Research Database (Denmark)

    Kjaer-Frifeldt, Sanne; Fredslund, Rikke; Lindebjerg, Jan

    2012-01-01

    To investigate the prognostic effect of three VEGF-A SNPs, -2578, -460 and 405, as well as the corresponding haplotype combinations, in a unique population of stage II colon cancer patients.......To investigate the prognostic effect of three VEGF-A SNPs, -2578, -460 and 405, as well as the corresponding haplotype combinations, in a unique population of stage II colon cancer patients....

  10. Transcriptional profiling of mouse uterus at pre-implantation stage under VEGF repression.

    Directory of Open Access Journals (Sweden)

    Yan Ji

    Full Text Available Uterus development during pre-implantation stage affects implantation process and embryo growth. Aberrant uterus development is associated with many human reproductive diseases. Among the factors regulating uterus development, vascular remodeling promoters are critical for uterus function and fertility. Vascular endothelial growth factor (VEGF, as one of the major members, has been found to be important in endothelial cell growth and blood vessel development, as well as in non-endothelial cells. VEGF mediation in reproduction has been broadly studied, but VEGF-induced transcriptional machinery during implantation window has not been systematically studied. In this study, a genetically repressed VEGF mouse model was used to analyze uterus transcriptome at gestation 2.5 (G2.5 by Solexa/Illumina's digital gene expression (DGE system. A number of 831 uterus-specific and 2398 VEGF-regulated genes were identified. Gene ontology (GO analysis indicated that genes actively involved in uterus development were members of collagen biosynthesis, cell proliferation and cell apoptosis. Uterus-specific genes were enriched in activities of phosphatidyl inositol phosphate kinase, histone H3-K36 demethylation and protein acetylation. Among VEGF-regulated genes, up-regulated were associated with RNA polymerase III activity while down-regulated were strongly related with muscle development. Comparable numbers of antisense transcripts were identified. Expression levels of the antisense transcripts were found tightly correlated with their sense expression levels, an indication of possibly non-specific transcripts generated around the active promoters and enhancers. The antisense transcripts with exceptionally high or low expression levels and the antisense transcripts under VEGF regulation were also identified. These transcripts may be important candidates in regulation of uterus development. This study provides a global survey on genes and antisense transcripts

  11. Genetic variation in VEGF does not contribute significantly to the risk of congenital cardiovascular malformation.

    Directory of Open Access Journals (Sweden)

    Helen R Griffin

    Full Text Available Several previous studies have investigated the role of common promoter variants in the vascular endothelial growth factor (VEGF gene in causing congenital cardiovascular malformation (CVM. However, results have been discrepant between studies and no study to date has comprehensively characterised variation throughout the gene. We genotyped 771 CVM cases, of whom 595 had the outflow tract malformation Tetralogy of Fallot (TOF, and carried out TDT and case-control analyses using haplotype-tagging SNPs in VEGF. We carried out a meta-analysis of previous case-control or family-based studies that had typed VEGF promoter SNPs, which included an additional 570 CVM cases. To identify rare variants potentially causative of CVM, we carried out mutation screening in all VEGF exons and splice sites in 93 TOF cases. There was no significant effect of any VEGF haplotype-tagging SNP on the risk of CVM in our analyses of 771 probands. When the results of this and all previous studies were combined, there was no significant effect of the VEGF promoter SNPs rs699947 (OR 1.05 [95% CI 0.95-1.17]; rs1570360 (OR 1.17 [95% CI 0.99-1.26]; and rs2010963 (OR 1.04 [95% CI 0.93-1.16] on the risk of CVM in 1341 cases. Mutation screening of 93 TOF cases revealed no VEGF coding sequence variants and no changes at splice consensus sequences. Genetic variation in VEGF appears to play a small role, if any, in outflow tract CVM susceptibility.

  12. Covalent immobilisation of VEGF on plasma-coated electrospun scaffolds for tissue engineering applications.

    Science.gov (United States)

    Guex, A G; Hegemann, D; Giraud, M N; Tevaearai, H T; Popa, A M; Rossi, R M; Fortunato, G

    2014-11-01

    Recent findings in the field of biomaterials and tissue engineering provide evidence that surface immobilised growth factors display enhanced stability and induce prolonged function. Cell response can be regulated by material properties and at the site of interest. To this end, we developed scaffolds with covalently bound vascular endothelial growth factor (VEGF) and evaluated their mitogenic effect on endothelial cells in vitro. Nano- (254±133 nm) or micro-fibrous (4.0±0.4 μm) poly(ɛ-caprolactone) (PCL) non-wovens were produced by electrospinning and coated in a radio frequency (RF) plasma process to induce an oxygen functional hydrocarbon layer. Implemented carboxylic acid groups were converted into amine-reactive esters and covalently coupled to VEGF by forming stable amide bonds (standard EDC/NHS chemistry). Substrates were analysed by X-ray photoelectron spectroscopy (XPS), enzyme-linked immuno-assays (ELISA) and immunohistochemistry (anti-VEGF antibody and VEGF-R2 binding). Depending on the reaction conditions, immobilised VEGF was present at 127±47 ng to 941±199 ng per substrate (6mm diameter; concentrations of 4.5 ng mm(-2) or 33.3 ng mm(-2), respectively). Immunohistochemistry provided evidence for biological integrity of immobilised VEGF. Endothelial cell number of primary endothelial cells or immortalised endothelial cells were significantly enhanced on VEGF-functionalised scaffolds compared to native PCL scaffolds. This indicates a sustained activity of immobilised VEGF over a culture period of nine days. We present a versatile method for the fabrication of growth factor-loaded scaffolds at specific concentrations. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Platelet activation determines angiopoietin-1 and VEGF levels in malaria: implications for their use as biomarkers.

    Directory of Open Access Journals (Sweden)

    Judith Brouwers

    Full Text Available INTRODUCTION: The angiogenic proteins angiopoietin (Ang-1, Ang-2 and vascular endothelial growth factor (VEGF are regulators of endothelial inflammation and integrity. Since platelets store large amounts of Ang-1 and VEGF, measurement of circulation levels of these proteins is sensitive to platelet number, in vivo platelet activation and inadvertent platelet activation during blood processing. We studied plasma Ang-1, Ang-2 and VEGF levels in malaria patients, taking the necessary precautions to avoid ex vivo platelet activation, and related plasma levels to platelet count and the soluble platelet activation markers P-selectin and CXCL7. METHODS: Plasma levels of Ang-1, Ang-2, VEGF, P-selectin and CXCL7 were measured in CTAD plasma, minimizing ex vivo platelet activation, in 27 patients with febrile Plasmodium falciparum malaria at presentation and day 2 and 5 of treatment and in 25 healthy controls. RESULTS: Levels of Ang-1, Ang-2 and VEGF were higher at day 0 in malaria patients compared to healthy controls. Ang-2 levels, which is a marker of endothelial activation, decreased after start of antimalarial treatment. In contrast, Ang-1 and VEGF plasma levels increased and this corresponded with the increase in platelet number. Soluble P-selectin and CXCL7 levels followed the same trend as Ang-1 and VEGF levels. Plasma levels of these four proteins correlated strongly in malaria patients, but only moderately in controls. CONCLUSION: In contrast to previous studies, we found elevated plasma levels of Ang-1 and VEGF in patients with malaria resulting from in vivo platelet activation. Ang-1 release from platelets may be important to dampen the disturbing effects of Ang-2 on the endothelium. Evaluation of plasma levels of these angiogenic proteins requires close adherence to a stringent protocol to minimize ex vivo platelet activation.

  14. Moderation of calpain activity promotes neovascular integration and lumen formation during VEGF-induced pathological angiogenesis.

    Directory of Open Access Journals (Sweden)

    Mien V Hoang

    2010-10-01

    Full Text Available Successful neovascularization requires that sprouting endothelial cells (ECs integrate to form new vascular networks. However, architecturally defective, poorly integrated vessels with blind ends are typical of pathological angiogenesis induced by vascular endothelial growth factor-A (VEGF, thereby limiting the utility of VEGF for therapeutic angiogenesis and aggravating ischemia-related pathologies. Here we investigated the possibility that over-exuberant calpain activity is responsible for aberrant VEGF neovessel architecture and integration. Calpains are a family of intracellular calcium-dependent, non-lysosomal cysteine proteases that regulate cellular functions through proteolysis of numerous substrates.In a mouse skin model of VEGF-driven angiogenesis, retroviral transduction with dominant-negative (DN calpain-I promoted neovessel integration and lumen formation, reduced blind ends, and improved vascular perfusion. Moderate doses of calpain inhibitor-I improved VEGF-driven angiogenesis similarly to DN calpain-I. Conversely, retroviral transduction with wild-type (WT calpain-I abolished neovessel integration and lumen formation. In vitro, moderate suppression of calpain activity with DN calpain-I or calpain inhibitor-I increased the microtubule-stabilizing protein tau in endothelial cells (ECs, increased the average length of microtubules, increased actin cable length, and increased the interconnectivity of vascular cords. Conversely, WT calpain-I diminished tau, collapsed microtubules, disrupted actin cables, and inhibited integration of cord networks. Consistent with the critical importance of microtubules for vascular network integration, the microtubule-stabilizing agent taxol supported vascular cord integration whereas microtubule dissolution with nocodazole collapsed cord networks.These findings implicate VEGF-induction of calpain activity and impairment of cytoskeletal dynamics in the failure of VEGF-induced neovessels to form and

  15. VEGF-releasing suture material for enhancement of vascularization: development, in vitro and in vivo study.

    Science.gov (United States)

    Bigalke, Christian; Luderer, Frank; Wulf, Katharina; Storm, Thilo; Löbler, Marian; Arbeiter, Daniela; Rau, Bettina M; Nizze, Horst; Vollmar, Brigitte; Schmitz, Klaus-Peter; Klar, Ernst; Sternberg, Katrin

    2014-12-01

    As it has been demonstrated that bioactive substances can be delivered locally using coated surgical suture materials, the authors developed a vascular endothelial growth factor (VEGF)-releasing suture material that should promote vascularization and potentially wound healing. In this context, the study focused on the characterization of the developed suture material and the verification of its biological activity, as well as establishing a coating process that allows reproducible and stable coating of a commercially available polydioxanone suture material with poly(l-lactide) (PLLA) and 0.1μg and 1.0μg VEGF. The in vitro VEGF release kinetics was studied using a Sandwich ELISA. The biological activity of the released VEGF was investigated in vitro using human umbilical vein endothelial cells. The potential of the VEGF-releasing suture material was also studied in vivo 5days after implantation in the hind limb of Wistar rats, when the histological findings were analyzed. The essential results, enhanced cell viability in vitro as well as significantly increased vascularization in vivo, were achieved using PLLA/1.0μg VEGF-coated suture material. Furthermore, ELISA measurements revealed a high reproducibility of the VEGF release behavior. Based on the results achieved regarding the dose-effect relationship of VEGF, the stability during its processing and the release behavior, it can be predicted that a bioactive suture material would be successful in later in vivo studies. Therefore, this knowledge could be the basis for future studies, where bioactive substances with different modes of action are combined for targeted, overall enhancement of wound healing. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  16. Serum vascular endothelial growth factor (VEGF) is elevated in GH deficient adults.

    Science.gov (United States)

    Murray, Robert D; Randeva, Harpal S; Lewandowski, Krzysztof C; Komorowski, Jan; Lawrance, Jeremy A; Adams, Judith E; Shalet, Stephen M

    2011-04-01

    GHD adults exhibit a number of adverse surrogate markers of vascular risk culminating in excess vascular morbidity and mortality. Vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of a number of vascular morbidities. Furthermore, serum levels decrease following GH replacement in GHD adults, though it remains unclear if levels are significantly elevated in untreated individuals. A cross-sectional case-control study. We measured fasting serum VEGF, MMP2, and MMP9 in 27 patients with GHD, 24 with partial GHD (GHI), and 25 sex- and age-matched controls. GHD (483±334 vs 326±180ng/l, P=0.04), but not GHI (354±192 vs 326±180ng/l, P=n/s) adults had significantly elevated VEGF levels compared with controls. Neither MMP2, nor MMP9 levels were elevated in the patient groups. Serum VEGF levels correlated positively with LDL-cholesterol (R=0.34, P=0.004) and serum MMP9 values (R=0.36, P=0.002), and negatively with IGF-I values, however, no correlation was observed with MMP2. Multiple regression analysis with VEGF levels as the dependent variable, and age, gender, % fat mass, LDL-C, insulin and IGF-I as independent variables revealed VEGF levels to be dependent on LDL-C alone (P=0.003, R=0.36). GHD adults have elevated VEGF levels, which correlate with MMP9 levels. Both VEGF and MMP9 are associated with vascular pathologies and may provide insight in to the pathophysiological mechanisms underlying the increased vascular morbidity and mortality observed in GHD adults. Copyright © 2011 Growth Hormone Research Society. Published by Elsevier Ltd. All rights reserved.

  17. VEGF-C Is a Thyroid Marker of Malignancy Superior to VEGF-A in the Differential Diagnostics of Thyroid Lesions.

    Science.gov (United States)

    Woliński, Kosma; Stangierski, Adam; Szczepanek-Parulska, Ewelina; Gurgul, Edyta; Budny, Bartłomiej; Wrotkowska, Elzbieta; Biczysko, Maciej; Ruchala, Marek

    2016-01-01

    Thyroid nodular goiter is one of the most common medical conditions affecting even over a half of adult population. The risk of malignancy is rather small but noticeable-estimated by numerous studies to be about 3-10%. The definite differentiation between benign and malignant ones is a vital issue in endocrine practice. The aim of the current study was to assess the expression of vascular endothelial growth factor A (VEGF-A) and VEGF-C on the mRNA level in FNAB washouts in case of benign and malignant thyroid nodules and to evaluate the diagnostic value of these markers of malignancy. Patients undergoing fine-needle aspiration biopsy (FNAB) in our department between January 2013 and May 2014 were included. In case of all patients who gave the written consent, after ultrasonography (US) and fine-needle aspiration biopsy (FNAB) performed as routine medical procedure the needle was flushed with RNA Later solution, the washouts were frozen in -80 Celsius degrees. Expression of VEGF-A and VEGF-C and GADPH (reference gene) was assessed in washouts on the mRNA level using the real-time PCR technique. Probes of patients who underwent subsequent thyroidectomy and were diagnosed with differentiated thyroid cancer (DTC; proved by post-surgical histopathology) were analyzed. Similar number of patients with benign cytology were randomly selected to be a control group. Thirty one DTCs and 28 benign thyroid lesions were analyzed. Expression of VEGF-A was insignificantly higher in patients with DTCs (p = 0.13). Expression of VEGF-C was significantly higher in patients with DTC. The relative expression of VEGF-C (in comparison with GAPDH) was 0.0049 for DTCs and 0.00070 for benign lesions, medians - 0.0036 and 0.000024 respectively (pthyroid nodules and should be interpreted carefully. Further studies on larger groups are indicated. However, measurement of VEGF-C on mRNA level can bring important information without exposing patient for additional risk and invasive procedures.

  18. Placenta growth factor-1 antagonizes VEGF-induced angiogenesis and tumor growth by the formation of functionally inactive PIGF-1/VEGF heterodimers

    DEFF Research Database (Denmark)

    Eriksson, A.; Cao, R.; Pawliuk, R.

    2002-01-01

    , the biological function of its related homolog, placenta growth factor (PlGF), is poorly understood. Here we demonstrate that PlGF-1, an alternatively spliced isoform of the PlGF gene, antagonizes VEGF-induced angiogenesis when both factors are coexpressed in murine fibrosarcoma cells. Overexpression of PlGF-1...... signaling pathways. Further, PlGF-1 inhibits the growth of a murine fibrosarcoma by approximately 90% when PlGF-1-expressing tumor cells are implanted in syngeneic mice. In contrast, overexpression of human VEGF in murine tumor cells causes accelerated and exponential growth of primary fibrosarcomas...

  19. Captopril Modulates Hypoxia-Inducible Factors and Erythropoietin Responses in a Murine Model of Total Body Irradiation

    Science.gov (United States)

    2011-01-01

    erythroid cell loss/imbalance and erythroid demand with captopril- treatment. ACE inhibitors are being used extensively for treatment of breast cancer ...expression in tumor cells and other tissues. Oncologist. 2004;9(suppl 5):18–30. 28. Lam SY, Tipoe GL, Fung ML. Upregulation of erythropoietin and its...ers KE. Synergistic effects of co-administration of angiotensin 1-7 and Neupogen on hematopoietic recovery in mice. Cancer Chemother Pharmacol

  20. Enhanced Vascularization in Hybrid PCL/Gelatin Fibrous Scaffolds with Sustained Release of VEGF

    Directory of Open Access Journals (Sweden)

    Kai Wang

    2015-01-01

    Full Text Available Creating a long-lasting and functional vasculature represents one of the most fundamental challenges in tissue engineering. VEGF has been widely accepted as a potent angiogenic factor involved in the early stages of blood vessel formation. In this study, fibrous scaffolds that consist of PCL and gelatin fibers were fabricated. The gelatin fibers were further functionalized by heparin immobilization, which provides binding sites for VEGF and thus enables the sustained release of VEGF. In vitro release test confirms the sustained releasing profile of VEGF, and stable release was observed over a time period of 25 days. In vitro cell assay indicates that VEGF release significantly promoted the proliferation of endothelial cells. More importantly, in vivo subcutaneous implantation reflects that vascularization has been effectively enhanced in the PCL/gelatin scaffolds compared with the PCL counterpart due to the sustained release of VEGF. Therefore, the heparinized PCL/gelatin scaffolds developed in this study may be a promising candidate for regeneration of complex tissues with sufficient vascularization.

  1. Local VEGF inhibition prevents ovarian alterations associated with ovarian hyperstimulation syndrome.

    Science.gov (United States)

    Scotti, Leopoldina; Abramovich, Dalhia; Pascuali, Natalia; Irusta, Griselda; Meresman, Gabriela; Tesone, Marta; Parborell, Fernanda

    2014-10-01

    The relationship between human chorionic gonadotropin and ovarian hyperstimulation syndrome (OHSS) is partially mediated by vascular endothelial growth factor A (VEGF). The aim of this study was to investigate the effects of VEGF inhibition on the development of corpora lutea (CL) and cystic structures, steroidogenesis, apoptosis, cell proliferation, endothelial cell area, VEGF receptors (KDR and Flt-1), claudin-5 and occludin levels in ovaries from an OHSS rat model. The VEGF inhibitor used (VEGF receptor-1 (FLT-1)/Fc chimera, TRAP) decreased the concentrations of progesterone and estradiol as well as the percentage of CL and cystic structures in OHSS rats, and increased apoptosis in CL. Endothelial cell area in CL and KDR expression and its phosphorylation were increased, whereas claudin-5 and occludin levels were decreased in the OHSS compared to the control TRAP reversed these parameters. Our findings indicate that VEGF inhibition prevents the early onset of OHSS and decreases its severity in rats. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Excess HB-EGF, which promotes VEGF signaling, leads to hydrocephalus

    Science.gov (United States)

    Shim, Joon W.; Sandlund, Johanna; Hameed, Mustafa Q.; Blazer-Yost, Bonnie; Zhou, Feng C.; Klagsbrun, Michael; Madsen, Joseph R.

    2016-01-01

    Heparin binding epidermal growth factor-like growth factor (HB-EGF) is an angiogenic factor mediating radial migration of the developing forebrain, while vascular endothelial growth factor (VEGF) is known to influence rostral migratory stream in rodents. Cell migratory defects have been identified in animal models of hydrocephalus; however, the relationship between HB-EGF and hydrocephalus is unclear. We show that mice overexpressing human HB-EGF with β-galactosidase reporter exhibit an elevated VEGF, localization of β-galactosidase outside the subventricular zone (SVZ), subarachnoid hemorrhage, and ventriculomegaly. In Wistar polycystic kidney rats with hydrocephalus, alteration of migratory trajectory is detected. Furthermore, VEGF infusions into the rats result in ventriculomegaly with an increase of SVZ neuroblast in rostral migratory stream, whereas VEGF ligand inhibition prevents it. Our results support the idea that excess HB-EGF leads to a significant elevation of VEGF and ventricular dilatation. These data suggest a potential pathophysiological mechanism that elevated HB-EGF can elicit VEGF induction and hydrocephalus. PMID:27243144

  3. Tumor VEGF:VEGFR2 autocrine feed-forward loop triggers angiogenesis in lung cancer.

    Science.gov (United States)

    Chatterjee, Sampurna; Heukamp, Lukas C; Siobal, Maike; Schöttle, Jakob; Wieczorek, Caroline; Peifer, Martin; Frasca, Davide; Koker, Mirjam; König, Katharina; Meder, Lydia; Rauh, Daniel; Buettner, Reinhard; Wolf, Jürgen; Brekken, Rolf A; Neumaier, Bernd; Christofori, Gerhard; Thomas, Roman K; Ullrich, Roland T

    2013-04-01

    The molecular mechanisms that control the balance between antiangiogenic and proangiogenic factors and initiate the angiogenic switch in tumors remain poorly defined. By combining chemical genetics with multimodal imaging, we have identified an autocrine feed-forward loop in tumor cells in which tumor-derived VEGF stimulates VEGF production via VEGFR2-dependent activation of mTOR, substantially amplifying the initial proangiogenic signal. Disruption of this feed-forward loop by chemical perturbation or knockdown of VEGFR2 in tumor cells dramatically inhibited production of VEGF in vitro and in vivo. This disruption was sufficient to prevent tumor growth in vivo. In patients with lung cancer, we found that this VEGF:VEGFR2 feed-forward loop was active, as the level of VEGF/VEGFR2 binding in tumor cells was highly correlated to tumor angiogenesis. We further demonstrated that inhibition of tumor cell VEGFR2 induces feedback activation of the IRS/MAPK signaling cascade. Most strikingly, combined pharmacological inhibition of VEGFR2 (ZD6474) and MEK (PD0325901) in tumor cells resulted in dramatic tumor shrinkage, whereas monotherapy only modestly slowed tumor growth. Thus, a tumor cell-autonomous VEGF:VEGFR2 feed-forward loop provides signal amplification required for the establishment of fully angiogenic tumors in lung cancer. Interrupting this feed-forward loop switches tumor cells from an angiogenic to a proliferative phenotype that sensitizes tumor cells to MAPK inhibition.

  4. A potential role for VEGF in the diagnostic approach of pleural effusions

    Science.gov (United States)

    Psatha, Aggeliki; Makris, Demosthenes; Daniil, Zoe; Kiropoulos, Theodoros; Gourgoulianis, Konstantinos

    2016-01-01

    Background Vascular endothelial growth factor (VEGF) may play a role in pleural fluid formation, as it represents a potent inducer of capillary permeability. We aimed to investigate the diagnostic utility of VEGF levels in pleural fluid and serum in patients with pleural effusions with initially negative diagnostic work up. Methods Seventy-one patients with exudative lymphocytic pleural effusions undiagnosed after initial diagnostic work up were enrolled in this prospective study and their clinical course was followed up to 24 months. VEGF levels were measured in serum and pleural fluid by using immunoenzymometric assay. Results During the follow up period, in 43 patients the pleural effusion was eventually attributed to malignancy while in the rest 28 patients it was due to non-malignant causes (benign and unknown origin). Patients with malignancy had significantly higher VEGF levels in pleural fluid compared to patients with non-malignant effusions (1,506 vs. 588 pg/dL, P=0.0001), while no statistically significant difference was found in the VEGF serum levels between the two groups. Conclusions Pleural VEGF levels may be helpful in identifying malignant pleural effusion (MPE) in patients with negative diagnostic work up at the initial assessment and help in selecting patients for more invasive procedures. PMID:27499957

  5. Immunohistochemical Expression of VEGF and Podoplanin in Uterine Cervical Squamous Intraepithelial Lesions

    Directory of Open Access Journals (Sweden)

    Patrícia Napoli Belfort-Mattos

    2016-01-01

    Full Text Available VEGF and podoplanin (PDPN have been identified as angiogenesis and/or lymphangiogenesis regulators and might be essential to restrict tumor growth, progression, and metastasis. In the present study, we evaluate the association between the expression of these markers and CIN grade. Immunohistochemistry was performed in 234 uterine cervical samples using conventional histologic sections or TMA with the monoclonal antibodies to VEGF (C-1 clone and podoplanin (D2-40 clone. Positive-staining rates of VEGF in 191 CIN specimens were significantly associated with histological grade (P<0.001. Negative and/or focal immunostaining for PDPN were more frequent in CIN 3 (P=0.016. We found that patients with CIN 3 more frequently had strong and more diffuse staining for VEGF and diminished staining for PDPN (P=0.018. Strong and more diffuse VEGF immunoexpressions in CIN 2 and CIN 3 were detected when compared to CIN 1. Negative and/or focal PDPN immunoexpression appear to be more frequent in CIN 3. Moderate to strong VEGF expression may be a tendency among patients with high-grade lesions and diminished PDPN expression.

  6. Expression of VEGF-D in epithelial ovarian cancer and its relationship to lymphatic metastasis.

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    He, Lixia; He, Junyong; Zhao, Xia

    2016-03-01

    To investigate the contribution of vascular endothelial growth factor (VEGF)-D to tumor progression, tumor lymphangiogenesis and lymphatic metastasis in epithelial ovarian cancer. The expression profiles of VEGF-D in 18 benign, 14 borderline and 87 malignant epithelial ovarian cancers were examined using immunohistochemical (IHC) staining. Lymphatic vessels were identified using IHC staining on lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), which is a lymph-specific receptor for hyaluronan in identifying lymphatic vessels. The potential correlation among VEGF-D, lymphatic vessel density (LVD) and clinico-pathological factors of the epithelial ovarian cancer was also analyzed. Positive IHC staining of VEGF-D was observed in 17% of benign, 21% of borderline and 80% of malignant epithelial ovarian tumors specimens. In the epithelial ovarian cancer specimens, the LVD was 3.41 ± 2.37 in the VEGF-D negative (17 patients), 5.42 ± 3.49 in the weak (26 patients), 7.22 ± 2.36 in the moderate (27 patients) and 7.35 ± 4.06 in the strong (17 patients) groups, respectively. Additionally, the expression of VEGF-D was positively correlated with LVD (r = 0.415, P ovarian cancer than in lymph node-negative patients (P = 0.009, P ovarian cancer. © 2013 Wiley Publishing Asia Pty Ltd.

  7. Nitric Oxide Mediates Bleomycin-Induced Angiogenesis and Pulmonary Fibrosis via Regulation of VEGF

    Science.gov (United States)

    Iyer, Anand Krishnan V.; Ramesh, Vani; Castro, Carlos A.; Kaushik, Vivek; Kulkarni, Yogesh M.; Wright, Clayton A.; Venkatadri, Rajkumar; Rojanasakul, Yon; Azad, Neelam

    2015-01-01

    Pulmonary fibrosis is a progressive lung disease hallmarked by increased fibroblast proliferation, amplified levels of extracellular matrix deposition and increased angiogenesis. Although dysregulation of angiogenic mediators has been implicated in pulmonary fibrosis, the specific rate-limiting angiogenic markers involved and their role in the progression of pulmonary fibrosis remains unclear. We demonstrate that bleomycin treatment induces angiogenesis, and inhibition of the central angiogenic mediator VEGF using anti-VEGF antibody CBO-P11 significantly attenuates bleomycin-induced pulmonary fibrosis in vivo. Bleomycin-induced nitric oxide (NO) was observed to be the key upstream regulator of VEGF via the PI3k/Akt pathway. VEGF regulated other important angiogenic proteins including PAI-1 and IL-8 in response to bleomycin exposure. Inhibition of NO and VEGF activity significantly mitigated bleomycin-induced angiogenic and fibrogenic responses. NO and VEGF are key mediators of bleomycin-induced pulmonary fibrosis, and could serve as important targets against this debilitating disease. Overall, our data suggests an important role for angiogenic mediators in the pathogenesis of bleomycin-induced pulmonary fibrosis. PMID:25919965

  8. CD47 signaling regulates the immunosuppressive activity of VEGF in T cells*

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    Kaur, Sukhbir; Chang, Tiffany; Singh, Satya P.; Lim, Langston; Mannan, Poonam; Garfield, Susan H.; Pendrak, Michael L.; Pantoja, David R. Soto; Rosenberg, Avi Z.; Jin, Shelly; Roberts, David D.

    2014-01-01

    Thromobospondin-1 inhibits angiogenesis in part by interacting with the ubiquitous cell surface receptor CD47. In endothelial cells, CD47 interacts directly with vascular endothelial growth factor receptor-2 (VEGFR2), and thrombospondin-1 inhibits VEGFR2 phosphorylation and signaling by disrupting this association. We now show that CD47 similarly associates with and regulates VEGFR2 in T cells. Thrombospondin-1 inhibits phosphorylation of VEGFR2 and its downstream target Src in wild type but not in CD47-deficient human Jurkat and primary murine T cells. VEGFR2 signaling inhibits proliferation and TCR signaling in wild type T cells. However, ligation of CD47 by thrombospondin-1 or loss of CD47 expression reverses some inhibitory effects of VEGF on proliferation and T cell activation. We further found that VEGF and VEGFR2 expression are up-regulated in CD47-deficient murine CD4+ and human Jurkat T cells, and the resulting autocrine VEGFR2 signaling enhances proliferation and some TCR responses in the absence of CD47. Thus, CD47 signaling modulates the ability of VEGF to regulate proliferation and TCR signaling, and autocrine production of VEGF by T cells contributes to this regulation. This provides a mechanism to understand the context-dependent effects of thrombospondin-1 and VEGF on T cell activation and reveals an important role for CD47 signaling in regulating T cell production of the major angiogenic factor VEGF. PMID:25200950

  9. CD47 signaling regulates the immunosuppressive activity of VEGF in T cells.

    Science.gov (United States)

    Kaur, Sukhbir; Chang, Tiffany; Singh, Satya P; Lim, Langston; Mannan, Poonam; Garfield, Susan H; Pendrak, Michael L; Soto-Pantoja, David R; Rosenberg, Avi Z; Jin, Shelly; Roberts, David D

    2014-10-15

    Thrombospondin-1 (TSP1) inhibits angiogenesis, in part, by interacting with the ubiquitous cell-surface receptor CD47. In endothelial cells, CD47 interacts directly with vascular endothelial growth factor receptor (VEGFR)-2, and TSP1 inhibits VEGFR2 phosphorylation and signaling by disrupting this association. We show that CD47 similarly associates with and regulates VEGFR2 in T cells. TSP1 inhibits phosphorylation of VEGFR2 and its downstream target Src in wild type but not in CD47-deficient human Jurkat and primary murine T cells. VEGFR2 signaling inhibits proliferation and TCR signaling in wild type T cells. However, ligation of CD47 by TSP1 or loss of CD47 expression reverses some inhibitory effects of VEGF on proliferation and T cell activation. We further found that VEGF and VEGFR2 expression are upregulated in CD47-deficient murine CD4(+) and human Jurkat T cells, and the resulting autocrine VEGFR2 signaling enhances proliferation and some TCR responses in the absence of CD47. Thus, CD47 signaling modulates the ability of VEGF to regulate proliferation and TCR signaling, and autocrine production of VEGF by T cells contributes to this regulation. This provides a mechanism to understand the context-dependent effects of TSP1 and VEGF on T cell activation, and reveals an important role for CD47 signaling in regulating T cell production of the major angiogenic factor VEGF.

  10. Clinical significance of COX-2, GLUT-1 and VEGF expressions in endometrial cancer tissues.

    Science.gov (United States)

    Ma, Xiaoping; Hui, Yuzuo; Lin, Li; Wu, Yu; Zhang, Xian; Liu, Peishu

    2015-01-01

    To analyze the clinical significance of COX-2, GLUT-1 and VEGF expressions in endometrial cancer tissues. One hundred and eight tissue samples from the patients with endometrial cancer enrolled in our hospital from August 2011 to July 2014 were selected, including 60 normal tissue samples (normal group), 60 neoplastic tissue samples (neoplastic group) and 60 cancer tissue samples (cancer group). All the samples were subjected to immunohistochemical assay to detect the expressions of COX-2, GLUT-1 and VEGF. The clinical data were also investigated for correlation analysis. The positive rates of COX-2 in normal group, neoplastic group and cancer groups were 3.3%, 21.7% and 55.0% respectively. The positive rates of GLUT-1 in normal group, neoplastic group and cancer groups were 3.3%, 25.0% and 70.0% respectively. The positive rates of VEGF in normal group, neoplastic group and cancer groups were 1.7%, 23.3% and 63.3% respectively. With increasing stage of such cancer, decreasing degree of differentiation and lymphatic metastasis, the positive expression rates of COX-2, GLUT-1 and VEGF proteins were raised significantly (PGLUT-1 (r=0.207, PGLUT-1 and VEGF (r=0.758, PGLUT-1 and VEGF were highly prominent in endometrial cancer, especially in the patients with low degree of differentiation, late stage and metastasis. They functioned synergistically in the onset and progression of this cancer.

  11. Bee products prevent VEGF-induced angiogenesis in human umbilical vein endothelial cells

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    Mishima Satoshi

    2009-11-01

    Full Text Available Abstract Background Vascular endothelial growth factor (VEGF is a key regulator of pathogenic angiogenesis in diseases such as cancer and diabetic retinopathy. Bee products [royal jelly (RJ, bee pollen, and Chinese red propolis] from the honeybee, Apis mellifera, have been used as traditional health foods for centuries. The aim of this study was to investigate the anti-angiogenic effects of bee products using human umbilical vein endothelial cells (HUVECs. Methods In an in vitro tube formation assay, HUVECs and fibroblast cells were incubated for 14 days with VEGF and various concentrations of bee products [RJ, ethanol extract of bee pollen, ethanol extract of Chinese red propolis and its constituent, caffeic acid phenethyl ester (CAPE]. To clarify the mechanism of in vitro angiogenesis, HUVEC proliferation and migration were induced by VEGF with or without various concentrations of RJ, bee pollen, Chinese red propolis, and CAPE. Results RJ, bee pollen, Chinese red propolis, and CAPE significantly suppressed VEGF-induced in vitro tube formation in the descending order: CAPE > Chinese red propolis >> bee pollen > RJ. RJ and Chinese red propolis suppressed both VEGF-induced HUVEC proliferation and migration. In contrast, bee pollen and CAPE suppressed only the proliferation. Conclusion Among the bee products, Chinese red propolis and CAPE in particular showed strong suppressive effects against VEGF-induced angiogenesis. These findings indicate that Chinese red propolis and CAPE may have potential as preventive and therapeutic agents against angiogenesis-related human diseases.

  12. Use of Anti-VEGF Agents in Glaucoma Surgery

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    Mark Slabaugh

    2017-01-01

    Full Text Available A number of antivascular endothelial growth factor agents are currently used to treat ocular conditions. These agents have similar but distinct biologic qualities and have each been used in the management of neovascular glaucoma and in glaucoma surgery. Several different delivery methods are described, and because these medications are routinely given as intraocular injections, there are some benefits over traditional antifibrotic medications when used in glaucoma surgery. These agents effectively induce regression of anterior segment neovascularization and facilitate initial surgical management of neovascular glaucoma but the long-term outcome of this condition remains dependent on definitive management of the underlying process. Use in trabeculectomy or tube shunt procedures for other types of glaucoma has shown promise in affecting bleb morphology but has not yet been found to be as effective as traditional antifibrotic agents. There are reports of persistently raised intraocular pressure after repeated use of the anti-VEGF agents, possibly related to frequency of injection. These medications have wide application in the field of surgical glaucoma but a precise role has yet to be defined.

  13. Diffuse bone marrow uptake on whole-body F-18 fluorodeoxyglucose positron emission tomography in a patient taking recombinant erythropoietin.

    Science.gov (United States)

    Blodgett, Todd M; Ames, Jennifer T; Torok, Frank S; McCook, Barry M; Meltzer, Carolyn C

    2004-03-01

    F-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET) is used extensively in oncology to diagnose, stage, and restage patients with various malignancies. Many patients treated for malignancies develop neutropenia secondary to marrow suppressive chemotherapy and are subsequently treated with synthetic hematopoietic growth factors (HGF), both granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte-colony-stimulating factor (G-CSF). Patients taking HGF can present a diagnostic challenge for those interpreting PET because they can demonstrate diffuse marrow uptake on FDG-PET scans, mimicking diffuse bone marrow metastases. It has not been reported whether bone marrow uptake is affected on PET scans in patients taking erythropoietin, the erythroid-specific cell-line stimulator. We report a case of extensive diffuse bone marrow uptake in a 77-year-old man with a history of colon cancer who began taking erythropoietin 3 weeks before his PET scan. This case demonstrates the need to consider erythropoietin in the differential diagnosis of possible etiologies causing diffuse bone marrow uptake on PET scans.

  14. Rapid isolation and detection of erythropoietin in blood plasma by magnetic core gold nanoparticles and portable Raman spectroscopy.

    Science.gov (United States)

    Agoston, Roland; Izake, Emad L; Sivanesan, Arumugam; Lott, William B; Sillence, Martin; Steel, Rohan

    2016-04-01

    Isolating, purifying, and identifying proteins in complex biological matrices are often difficult, time consuming, and unreliable. Herein we describe a rapid screening technique for proteins in biological matrices that combines selective protein isolation with direct surface enhanced Raman spectroscopy (SERS) detection. Magnetic core gold nanoparticles were synthesized, characterized, and subsequently functionalized with recombinant human erythropoietin (rHuEPO)-specific antibody. The functionalized nanoparticles were used to capture rHuEPO from horse blood plasma within 15 min. The selective binding between the protein and the functionalized nanoparticles was monitored by SERS. The purified protein was then released from the nanoparticles' surface and directly spectroscopically identified on a commercial nanopillar SERS substrate. ELISA independently confirmed the SERS identification and quantified the released rHuEPO. Finally, the direct SERS detection of the extracted protein was successfully demonstrated for in-field screening by a handheld Raman spectrometer within 1 min sample measurement time. The rapid detection of recombinant human erythropoietin (rHuEPO) is important in competitive sports to screen for doping offences. In this article, the authors reported their technique of direct surface enhanced Raman spectroscopy (SERS) detection using magnetic core gold nanoparticles functionalized with recombinant human erythropoietin-specific antibody. The findings should open a new way for future detection of other proteins. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. The effects of erythropoietin signaling on telomerase regulation in non-erythroid malignant and non-malignant cells

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    Uziel, Orit, E-mail: Oritu@clalit.org.il [Felsenstein Medical Research Center, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv (Israel); Kanfer, Gil [Felsenstein Medical Research Center, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv (Israel); Dep. of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv (Israel); Beery, Einat [Felsenstein Medical Research Center, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv (Israel); Yelin, Dana; Shepshelovich, Daniel [Medicine A, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv (Israel); Bakhanashvili, Mary [Unit of Infectious Diseases, Sheba Medical Center, Tel-Hashomer (Israel); Nordenberg, Jardena [Felsenstein Medical Research Center, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv (Israel); Dep. of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv (Israel); Endocrinology Laboratory, Beilinson Medical Center, Petah-Tikva (Israel); Lahav, Meir [Felsenstein Medical Research Center, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv (Israel); Medicine A, Sackler School of Medicine, Tel-Aviv University, Ramat-Aviv (Israel)

    2014-07-18

    Highlights: • We assumed that some of erythropoietin adverse effects may be mediated by telomerase activity. • EPO administration increased telomerase activity, cells proliferation and migration. • The inhibition of telomerase modestly repressed the proliferative effect of erythropoietin. • Telomere shortening caused by long term inhibition of the enzyme totally abolished that effect. • This effect was mediated via the Lyn–AKT axis and not by the canonical JAK2–STAT pathway. - Abstract: Treatment with erythropoietin (EPO) in several cancers is associated with decreased survival due to cancer progression. Due to the major importance of telomerase in cancer biology we hypothesized that some of these effects may be mediated through EPO effect on telomerase. For this aim we explored the possible effects of EPO on telomerase regulation, cell migration and chemosensitivity in non-erythroid malignant and non-malignant cells. Cell proliferation, telomerase activity (TA) and cell migration increased in response to EPO. EPO had no effect on cancer cells sensitivity to cisplatinum and on the cell cycle status. The inhibition of telomerase modestly repressed the proliferative effect of EPO. Telomere shortening caused by long term inhibition of the enzyme abolished the effect of EPO, suggesting that EPO effects on cancer cells are related to telomere dynamics. TA was correlated with the levels of Epo-R. The increase in TA was mediated post-translationally through the Lyn-Src and not the canonical JAK2 pathway.

  16. Erythropoietin overrides the triggering effect of DNA platination products in a mouse model of Cisplatin-induced neuropathy

    Directory of Open Access Journals (Sweden)

    Egensperger Rupert

    2009-07-01

    Full Text Available Abstract Background Cisplatin mediates its antineoplastic activity by formation of distinct DNA intrastrand cross links. The clinical efficacy and desirable dose escalations of cisplatin are restricted by the accumulation of DNA lesions in dorsal root ganglion (DRG cells leading to sensory polyneuropathy (PNP. We investigated in a mouse model by which mechanism recombinant erythropoietin (rhEPO protects the peripheral nervous system from structural and functional damage caused by cisplatin treatment with special emphasis on DNA damage burden. Results A cumulative dose of 16 mg cisplatin/kg resulted in clear electrophysiological signs of neuropathy, which were significantly attenuated by concomitant erythropoietin (cisplatin 32,48 m/s ± 1,68 m/s; cisplatin + rhEPO 49,66 m/s ± 1,26 m/s; control 55,01 m/s ± 1,88 m/s; p Conclusion The protective effect of recombinant erythropoietin is not mediated by reducing the burden of DNA platination in the target cells, but it is likely to be due to a higher resistance of the target cells to the adverse effect of DNA damage. The increased frequency of intact mitochondria might also contribute to this protective role.

  17. Neutralizing Endogenous VEGF Following Traumatic Spinal Cord Injury Modulates Microvascular Plasticity but not Tissue Sparing or Functional Recovery

    Science.gov (United States)

    Benton, Richard L.; Maddie, Melissa A.; Gruenthal, Mark J.; Hagg, Theo; Whittemore, Scott R.

    2010-01-01

    Acute loss of spinal cord vascularity followed by an endogenous adaptive angiogenic response with concomitant microvascular dysfunction is a hallmark of traumatic spinal cord injury (SCI). Recently, the potent vasoactive factor vascular endothelial growth factor (VEGF) has received much attention as a putative therapeutic for the treatment of various neurodegenerative disorders, including SCI. Exogenous VEGF exerts both protective and destabilizing effects on microvascular elements and tissue following SCI but the role of endogenous VEGF is unclear. In the present study, we systemically applied a potent and well characterized soluble VEGF antagonist to adult C57Bl/6 mice post-SCI to elucidate the relative contribution of VEGF on the acute evolving microvascular response and its impact on functional recovery. While the VEGF Trap did not alter vascular density in the injury epicenter or penumbra, an overall increase in the number of Griffonia simplicifolia isolectin-B4 bound microvessels was observed, suggesting a VEGF-dependency to more subtle aspects of endothelial plasticity post-SCI. Neutralizing endogenous VEGF neither attenuated nor exacerbated chronic histopathology or functional recovery. These results support the idea that overall, endogenous VEGF is not neuroprotective or detrimental following traumatic SCI. Furthermore, they suggest that angiogenesis in traumatically injured spinal tissue is regulated by multiple effectors and is not limited by endogenous VEGF activation of affected spinal microvessels. PMID:19442162

  18. Inhibition of vascular endothelial growth factor (VEGF)-induced endothelial proliferation, arterial relaxation, vascular permeability and angiogenesis by dobesilate.

    Science.gov (United States)

    Angulo, Javier; Peiró, Concepción; Romacho, Tania; Fernández, Argentina; Cuevas, Begoña; González-Corrochano, Rocío; Giménez-Gallego, Guillermo; de Tejada, Iñigo Sáenz; Sánchez-Ferrer, Carlos F; Cuevas, Pedro

    2011-09-30

    Vascular endothelial growth factor (VEGF) is a key factor in angiogenesis and vascular permeability which is associated with many pathological processes. 2,5-hydroxybenzene sulfonate (DHBS; dobesilate) is a small molecule with anti-angiogenic activity that has been described as an inhibitor of fibroblast growth factors (FGF). The aim of the present study was to evaluate the effects of DHBS on VEGF-induced actions. The effects of DHBS were evaluated on VEGF-induced proliferation in human umbilical vein endothelial cells (HUVEC) and rat aorta relaxation, as well as on in vivo VEGF-induced skin vascular permeability and neovascularization in rats. DHBS at 50 and 100 μM concentration significantly inhibited the proliferation of HUVEC induced by VEGF (10 ng/ml), without significantly affecting HUVEC proliferation in the absence of VEGF. Rapid VEGF-induced activation of Akt in HUVEC was also prevented by DHBS (100 μM). Additionally, DHBS (2 μM) specifically inhibited the relaxation of rat aorta induced by VEGF (0.1 to 30 ng/ml), but not endothelium-dependent relaxation to acetylcholine (1 nM to 10 μM). The in vivo enhancement of vascular permeability caused by VEGF injection (50 μl at 10 ng/ml) in rat skin was also inhibited by DHBS co-administration (200 μM) (74.8±3.8% inhibition of dye extravasation). Administration of DHBS (200 mg/kg/day; i.p.) also reduced VEGF-induced angiogenesis in vivo. DHBS inhibits main responses elicited in vitro and in vivo by VEGF. As a dual antagonist of VEGF and FGF activities, DHBS could be of therapeutic interest in the treatment of diseases related to VEGF/FGF overproduction and excessive angiogenesis. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. The expression and underlying angiogenesis effect of DPC4 and VEGF on the progression of cervical carcinoma.

    Science.gov (United States)

    A, Yanni; Li, Ying; Zhao, Shuping

    2018-02-01

    The present study aimed to investigate the expression and roles of deleted in pancreatic carcinoma locus 4 (DPC4) and vascular endothelial growth factor (VEGF) in the development of cervical carcinoma. A total of 115 patients aged between 25 and 60 years were involved, including 19 cervical inflammation, 35 cervical intraepithelial neoplasia (CIN), and 61 cervical squamous-cell carcinoma (CSCC). The protein expression rates of DPC4 and VEGF in all samples were detected using immunohistochemistry. The protein levels of DPC4 and VEGF in CSCC samples were measured using ELISA. Microvessel density (MVD) of each CSCC sample was measured according to the Winder method. Association analysis between DPC4, VEGF and thrombospondin-1 (TSP-1) was conducted using Spearman's correlations. The negative expression rate of DPC4 [DPC4 (-)] and positive expression rate of VEGF [VEGF (+)] of the CSCC group were significantly higher compared with that in the cervical inflammation and CIN groups (P<0.05). In the CSCC group, the protein level of DPC4 decreased, while the VEGF level increased significantly compared with the healthy control group (P<0.05). The MVD in the DPC4 (-), VEGF (+) and TSP-1 (-) groups was significantly increased compared with that of the DPC4 (+), VEGF (-), and TSP-1 (+) groups (P<0.05). The expression of DPC4 was negatively associated with VEGF and TSP-1 (P<0.01). These results suggest that DPC4, VEGF and TSP-1 are involved in the carcinogenesis of cervical carcinoma by inducing angiogenesis. In addition, the loss of DPC4 induces angiogenesis through increasing VEGF. Thus, VEGF may be a target gene regulated by DPC4.

  20. Delineation of VEGF-regulated genes and functions in the cervix of pregnant rodents by DNA microarray analysis

    Directory of Open Access Journals (Sweden)

    Papka Raymond E

    2008-12-01

    Full Text Available Abstract Background VEGF-regulated genes in the cervices of pregnant and non-pregnant rodents (rats and mice were delineated by DNA microarray and Real Time PCR, after locally altering levels of or action of VEGF using VEGF agents, namely siRNA, VEGF receptor antagonist and mouse VEGF recombinant protein. Methods Tissues were analyzed by genome-wide DNA microarray analysis, Real-time and gel-based PCR, and SEM, to decipher VEGF function during cervical remodeling. Data were analyzed by EASE score (microarray and ANOVA (Real Time PCR followed by Scheffe's F-test for multiple comparisons. Results Of the 30,000 genes analyzed, about 4,200 genes were altered in expression by VEGF, i.e., expression of about 2,400 and 1,700 genes were down- and up-regulated, respectively. Based on EASE score, i.e., grouping of genes according to their biological process, cell component and molecular functions, a number of vascular- and non-vascular-related processes were found to be regulated by VEGF in the cervix, including immune response (including inflammatory, cell proliferation, protein kinase activity, and cell adhesion molecule activity. Of interest, mRNA levels of a select group of genes, known to or with potential to influence cervical remodeling were altered. For example, real time PCR analysis showed that levels of VCAM-1, a key molecule in leukocyte recruitment, endothelial adhesion, and subsequent trans-endothelial migration, were elevated about 10 folds by VEGF. Further, VEGF agents also altered mRNA levels of decorin, which is involved in cervical collagen fibrillogenesis, and expression of eNO, PLC and PKC mRNA, critical downstream mediators of VEGF. Of note, we show that VEGF may regulate cervical epithelial proliferation, as revealed by SEM. Conclusion These data are important in that they shed new insights in VEGF's possible roles and mechanisms in cervical events near-term, including cervical remodeling.

  1. Nitric oxide and hypoxia stimulate erythropoietin receptor via MAPK kinase in endothelial cells.

    Science.gov (United States)

    Cokic, Bojana B Beleslin; Cokic, Vladan P; Suresh, Sukanya; Wirt, Stacey; Noguchi, Constance Tom

    2014-03-01

    Erythropoietin receptor (EPOR) expression level determines the extent of erythropoietin (EPO) response. Previously we showed that EPOR expression in endothelial cells is increased at low oxygen tension and that EPO stimulation of endothelial cells during hypoxia can increase endothelial nitric oxide (NO) synthase (eNOS) expression and activation as well as NO production. We now observe that while EPO can stimulate NO production, NO in turn can regulate EPOR expression. Human umbilical vein endothelial cells (HUVEC) treated with 10-50 μM of NO donor diethylenetriamine NONOate (DETANO) for 24h showed significant induction of EPOR gene expression at 5% and 2% of oxygen. Also human bone marrow microvascular endothelial cell line (TrHBMEC) cultured at 21 and 2% oxygen with 50 μM DETANO demonstrated a time and oxygen dependent induction of EPOR mRNA expression after 24 and 48 h, particularly at low oxygen tension. EPOR protein was also induced by DETANO at 2% oxygen in TrHBMEC and HUVEC. The activation of signaling pathways by NO donor stimulation appeared to be distinct from EPO stimulation. In reporter gene assays, DETANO treatment of HeLa cells at 2% oxygen increased EPOR promoter activity indicated by a 48% increase in luciferase activity with a 2 kb EPOR promoter fragment and a 71% increase in activity with a minimal EPOR promoter fragment containing 0.2 kb 5'. We found that DETANO activated MAPK kinase in TrHBMEC both in normoxia and hypoxia, while MAPK kinase inhibition showed significant reduction of EPOR mRNA gene expression at low oxygen tension, suggesting MAPK involvement in NO mediated induction of EPOR. Furthermore, DETANO stimulated Akt anti-apoptotic activity after 30 min in normoxia, whereas it inhibited Akt phosphorylation in hypoxia. In contrast, EPO did not significantly increase MAPK activity while EPO stimulated Akt phosphorylation in TrHBMEC in normoxia and hypoxia. These observations provide a new effect of NO on EPOR expression to enhance EPO

  2. In-vivo detection of the erythropoietin receptor in tumours using positron emission tomography

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    Fuge, Felix; Doleschel, Dennis; Rix, Anne; Gremse, Felix; Lederle, Wiltrud; Kiessling, Fabian [RWTH Aachen University, Department for Experimental Molecular Imaging (ExMI), Medical Faculty, Aachen (Germany); Wessner, Axel [Roche Diagnostics GmbH, R and D RPD Protein Chemistry, Penzberg (Germany); Winz, Oliver; Mottaghy, Felix [University Clinic RWTH Aachen, Clinic for Nuclear Medicine, Aachen (Germany)

    2014-09-09

    Recombinant human erythropoietin (rhuEpo) is used clinically to treat anaemia. However, rhuEpo-treated cancer patients show decreased survival rates and erythropoietin receptor (EpoR) expression has been found in patient tumour tissue. Thus, rhuEpo application might promote EpoR{sup +} tumour progression. We therefore developed the positron emission tomography (PET)-probe {sup 68}Ga-DOTA-rhuEpo and evaluated its performance in EpoR{sup +} A549 non-small-cell lung cancer (NSCLC) xenografts. {sup 68}Ga-DOTA-rhuEpo was generated by coupling DOTA-hydrazide to carbohydrate side-chains of rhuEpo. Biodistribution was determined in tumour-bearing mice 0.5, 3, 6, and 9 h after probe injection. Competition experiments were performed by co-injecting {sup 68}Ga-DOTA-rhuEpo and rhuEpo in five-fold excess. Probe specificity was further evaluated histologically using Epo-Cy5.5 stainings. The blood half-life of {sup 68}Ga-DOTA-rhuEpo was 2.6 h and the unbound fraction was cleared by the liver and kidney. After 6 h, the highest tumour to muscle ratio was reached. The highest {sup 68}Ga-DOTA-rhuEpo accumulation was found in liver (10.06 ± 6.26%ID/ml), followed by bone marrow (1.87 ± 0.53%ID/ml), kidney (1.58 ± 0.39 %ID/ml), and tumour (0.99 ± 0.16%ID/ml). EpoR presence in these organs was histologically confirmed. Competition experiments showed significantly (p < 0.05) lower PET-signals in tumour and bone marrow at 3 and 6 h. {sup 68}Ga-DOTA-rhuEpo shows favourable pharmacokinetic properties and detects EpoR specifically. Therefore, it might become a valuable radiotracer to monitor EpoR status in tumours and support decision-making in anaemia therapy. (orig.)

  3. Recombinant human erythropoietin therapy for anemic cancer patients on combination chemotherapy.

    Science.gov (United States)

    Case, D C; Bukowski, R M; Carey, R W; Fishkin, E H; Henry, D H; Jacobson, R J; Jones, S E; Keller, A M; Kugler, J W; Nichols, C R

    1993-05-19

    Patients with advanced cancer frequently experience clinically significant anemia, which is often exacerbated by myelosuppressive chemotherapy. Consistent with the anemia of chronic disease, studies have documented serum erythropoietin levels that are inappropriately low for the degree of anemia in cancer patients. Myelosuppressive chemotherapy impairs erythropoiesis, which may not fully recover between treatment cycles. Recombinant human erythropoietin (rHuEPO) has been used safely and effectively to treat anemia in AIDS patients receiving zidovudine (AZT) and in patients with chronic renal failure. This study was designed to evaluate the clinical role of rHuEPO in reducing symptomatic anemia in patients with advanced cancer who were receiving myelosuppressive chemotherapy (excluding cisplatin). We studied 153 anemic cancer patients receiving cyclic combination chemotherapy in a prospective multicenter, double-blind, placebo-controlled trial. The patients were randomly assigned to receive either rHuEPO (150 U/kg) or placebo subcutaneously three times a week for a maximum of 12 weeks or until the hematocrit level increased to 38%-40%. If the hematocrit reached this target level before 12 weeks, the rHuEPO dose could be reduced to maintain the hematocrit at that level for the duration of the study. Response to rHuEPO therapy was assessed by measuring changes in hematocrit level, transfusion requirements, and quality of life. Quality-of-life assessment was based on patients' responses to questionnaires before and after the courses of therapy. The increase in hematocrit in the rHuEPO-treated group compared with hematocrit in the placebo-treated group was statistically significant (P = .0001) as measured by percentage point of change from baseline to final evaluation, by an increase in hematocrit level of six percentage points or more unrelated to transfusion, and by a rise in hematocrit level to 38% or more unrelated to transfusion. There was a trend toward the

  4. Epoetin alfa and beta differ in their erythropoietin isoform compositions and biological properties.

    Science.gov (United States)

    Storring, P L; Tiplady, R J; Gaines Das, R E; Stenning, B E; Lamikanra, A; Rafferty, B; Lee, J

    1998-01-01

    Epoetin alfa and beta are the two forms of recombinant DNA-derived erythropoietin (rEPO), both synthesized in Chinese hamster ovary cells, which are used for the treatment of erythropoietin (EPO)-responsive anaemias. Several batches of each of these rEPOs were compared for differences in their EPO isoform compositions by isoelectric focusing (IEF) and in a range of lectin-binding assays, and for differences in their EPO activities by in-vivo and in-vitro mouse bioassays and by immunoassay. Epoetin beta was found to differ from epoetin alfa in containing: (a) a greater proportion of more basic isoforms, (b) a greater proportion of EPO binding to Erythrina cristagalli agglutinin (which binds N-glycans with nonsialylated outer Gal beta1-4GlcNAc moieties), and (c) isoforms with higher in-vivo:in-vitro bioactivity ratios. Epoetin beta also contained slightly more than epoetin alfa of EPO binding to Lycopersicon esculentum agglutinin (which binds N-glycans containing repeating Gal beta1-4GlcNAc sequences), to the leucoagglutinin of Phaseolus vulgaris (which binds tetraantennary and 2,6-branched triantennary N-glycans) and to Agaricus bisporus agglutinin (which binds Gal beta1-3GalNAc containing O-glycans). No differences were found between the two rEPOs in their binding to a further five lectins. The differences between the isoform composition of epoetin alfa and beta, and the smaller inter-batch differences appear to be due to differences in glycosylation. The higher murine in-vivo:in-vitro bioactivity ratio of epoetin beta compared to epoetin alfa could not be explained in terms of differences in their degrees of sialylation, but was consistent with differences in their pharmacokinetics and pharmacodynamics observed in human subjects. There have been no reports that epoetin alfa differs from epoetin beta in its clinical efficacy, but the differences between epoetin alfa and beta in some analytical systems suggest that there might be a need for separate international

  5. Determining level of endogenous serum erythropoietin for differential diagnosis of polycythemia vera and symptomatic polycythemia

    Directory of Open Access Journals (Sweden)

    Kostyukevych O.M.

    2013-06-01

    Full Text Available The article deals with determining possibility of the assessment of the level of endogenous serum erythropoietin (EPO for differential diagnosis of polycythemia vera (PV and secondary erythrocytosis (SE. The determination of subnormal level of this cytokine for the diagnosis of PV has been detected. The relation between the level of endogenous erythropoietin and iron metabolism also has been analyzed. The study involved 88 patients with PV and 119 patients with SE. Statistically significant decrease in EPO concentration level has been detected in PV patients. The mean EPO level was equal to 6.38 ± 0.84 mIU/mL and 17.98 ±2.48 mIU/mL in PV and SE patients respectively. In control group of individuals EPO concentration was equal to 9,81 ±0,58 mIU/mL, the significant difference was found between all studied groups (р<0.01. According to our data, EPO was increased in 28 SE patients (23.53%, it was not observed in control group and in group of PV patients (φ*emp = 4.355, р<0.01. The decrease of EPO level in PV patients has been detected more often than in SE patients (84.09% versus 11.76% , φ*emp = 5.218, р<0.01, it has not been observed in control group. Only 14 (15.91% PV patients had normal EPO level, in contrast 77 (64.71% SE patients demonstrated normal EPO level (φ*emp = 4.578, р<0.01. The average level of ferritin was equal to 57.41 ± 9.74 ng/mL in PV patients and 199.77 ± 14.32 ng/mL in SE patients (р<0.01. Significantly more patients with PV demonstrated decrease of ferritin level (31.81% versus 7.56%, φ*emp = 4.438, р<0.01. Patients with SE more often had raised level of EPO than PV patients (15.12% versus 4.54%, φ*emp = 2.453, р<0.01. The sensitivity of test with detecting of the reduced level of EPO for the diagnosis of PV was 84.1%, specificity - 87.4%, positive predictive value - 83.1%, negative predictive value - 88.1%. Normal range of EPO significantly (rs = 0,5494 correlated with decreased levels of serum ferritin in

  6. Radiation-induced VEGF-C expression and endothelial cell proliferation in lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yu-Hsuan [National Taiwan University Hospital, Department of Oncology, Taipei (China); National Taiwan University, Pharmacological Institute, College of Medicine, Taipei (China); Pan, Shiow-Lin; Wang, Jing-Chi; Teng, Che-Ming [National Taiwan University, Pharmacological Institute, College of Medicine, Taipei (China); Kuo, Sung-Hsin [National Taiwan University Hospital, Department of Oncology, Taipei (China); National Taiwan University College of Medicine, Department of Internal Medicine, Taipei (China); Cheng, Jason Chia-Hsien [National Taiwan University Hospital, Department of Oncology, Taipei (China); National Taiwan University College of Medicine, Graduate Institute of Clinical Medicine, Taipei (China)

    2014-12-15

    The present study was undertaken to investigate whether radiation induces the expression of vascular endothelial growth factor C (VEGF-C) through activation of the PI3K/Akt/mTOR pathway,subsequently affecting endothelial cells. Radiotherapy-induced tumor micro-lymphatic vessel density (MLVD) was determined in a lung cancer xenograft model established in SCID mice. The protein expression and phosphorylation of members of the PI3K/Akt/mTOR pathway and VEGF-C secretion and mRNA expression in irradiated lung cancer cells were assessed by Western blot analysis, enzyme-linked immunosorbent assays (ELISAs), and reverse transcriptase-polymerase chain reaction (RT-PCR). Moreover, specific chemical inhibitors were used to evaluate the role of the PI3K/Akt/mTOR signaling pathway. Conditioned medium (CM) from irradiated control-siRNA or VEGF-C-siRNA-expressing A549 cells was used to evaluate the proliferation of endothelial cells by the MTT assay. Radiation increased VEGF-C expression in a dose-dependent manner over time at the protein but not at the mRNA level. Radiation also up-regulated the phosphorylation of Akt, mTOR, 4EBP, and eIF4E, but not of p70S6K. Radiation-induced VEGF-C expression was down-regulated by LY294002 and rapamycin (both p < 0.05). Furthermore, CM from irradiated A549 cells enhanced human umbilical vein endothelial cell (HUVEC) and lymphatic endothelial cell (LEC) proliferation, which was not observed with CM from irradiated VEGF-C-siRNA-expressing A549 cells. Radiation-induced activation of the PI3K/Akt/mTOR signaling pathway increases VEGF-C expression in lung cancer cells, thereby promoting endothelial cell proliferation. (orig.) [German] Die vorliegende Studie untersucht, ob die Strahlung die Expression von VEGF-C (vascular endothelial growth factor C) mittels Aktivierung des PI3K/Akt/mTOR-Signalwegs induziert und anschliessend die endothelialen Zellen beeinflusst. Die durch Strahlentherapie induzierte Mikrolymphgefaessdichte (MLVD) im Tumor wurde in

  7. Bacterial antigen induced release of soluble vascular endothelial growth factor (VEGF) and VEGFR1 before and after surgery

    DEFF Research Database (Denmark)

    Svendsen, Mads N; Lykke, J; Werther, Kim

    2005-01-01

    OBJECTIVE: The influence of surgery on release of soluble vascular endothelial growth factor (sVEGF) and the soluble inhibitory receptor (sVEGFR1) is unknown. The effect of major and minor surgery on variations in sVEGF and sVEGFR1 concentrations in vivo was studied, and on bacterial antigen...... concentrations in plasma changed during surgery. In vitro stimulation of blood samples with bacteria-derived antigens resulted in a significant increase in sVEGF (p Bacterial antigen-induced release of sVEGF correlated...... significantly with neutrophil cell counts (0.53 Bacterial antigen-induced sVEGFR1 release did not correlate with cell counts. CONCLUSIONS: Plasma sVEGF and sVEGFR1 concentrations did not change during surgery. In vitro bacterial stimulation led to increased release of sVEGF, which...

  8. A new impedimetric biosensor utilizing VEGF receptor-1 (Flt-1): early diagnosis of vascular endothelial growth factor in breast cancer.

    Science.gov (United States)

    Sezgintürk, Mustafa Kemal

    2011-06-15

    A new impedimetric biosensor, based on the use of vascular endothelial growth factor receptor-1 (VEGF-R1), was developed for the determination of vascular endothelial growth factor (VEGF). VEGF-R1 was immobilized through covalent coupling with 3-mercaptopropionic acid which formed a self-assembled monolayer on gold electrodes. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy techniques were employed to characterize the immobilization process and to detect VEGF. To successfully construct the biosensor current, experimental parameters were optimized. Kramers-Kronig Transform was performed on the experimental impedance data. The obtained results provided a linear response range from 10 to 70 pg/mL human VEGF. The applicability of the developed biosensor in the determination of VEGF in a spiked artificial human serum sample was experienced, yielding average recovery of 101%, in that order, with an average relative deviation value less than 5%. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Concentrations of VEGF and VEGFR1 in paired tumor arteries and veins in patients with rectal cancer

    DEFF Research Database (Denmark)

    Svendsen, Mads N; Lykke, Jakob; Werther, Kim

    2004-01-01

    a peripheral vein and intraoperative blood samples from a tumor artery, a tumor vein, and from a peripheral vein were drawn from 28 patients undergoing elective surgical resection of primary rectal cancer. Plasma concentrations of VEGF and VEGFR1 were determined by ELISA. Counts of white blood cells......Increased plasma concentrations of vascular endothelial growth factor (sVEGF) are associated with poor prognosis of colorectal cancer patients. The aim was to investigate the contribution of the tumor to plasma concentrations of VEGF and VEGF receptor 1 (VEGFR1). Preoperative blood samples from......VEGFR1 concentrations from preoperative to intraoperative samples was observed. There was a significant efflux of neutrophils to the tumor, but none of the observed changes in plasma VEGF or VEGFR1 levels correlated to changes in counts of white blood cells or platelets (sVEGF: 0.33

  10. Expression of HIF-1A/VEGF/ING-4 Axis in Pulmonary Sarcoidosis.

    Science.gov (United States)

    Piotrowski, W J; Kiszałkiewicz, J; Pastuszak-Lewandoska, D; Górski, P; Antczak, A; Migdalska-Sęk, M; Górski, W; Czarnecka, K H; Domańska, D; Nawrot, E; Brzeziańska-Lasota, E

    2015-01-01

    Angiogenesis/angiostasis regulated by hypoxia inducible factor-1A (HIF-1A)/vascular endothelial growth factor (VEGF)/inhibitor of growth protein 4 (ING-4) axis may be crucial for the course and outcome of sarcoidosis. Overexpression of angiogenic factors (activation of VEGF through HIF-1A) may predispose to chronic course and lung fibrosis, whereas immunoangiostasis (related to an overexpression of inhibitory ING-4) may be involved in granuloma formation in early sarcoid inflammation, or sustained or recurrent formation of granulomas. In this work we investigated gene expression of HIF-1A, VEGF and ING-4 in bronchoalveolar fluid (BALF) cells and in peripheral blood (PB) lymphocytes of sarcoidosis patients (n=94), to better understand mechanisms of the disease and to search for its biomarkers. The relative gene expression level (RQ value) was analyzed by qPCR. The results were evaluated according to the presence of lung parenchymal involvement (radiological stage I vs. II-IV), acute vs. insidious onset, lung function tests, calcium metabolism parameters, percentage of lymphocytes (BALL%) and BAL CD4+/CD8+ in BALF, age, and gender. In BALF cells, the ING-4 and VEGF RQ values were increased, while HIF-1A expression was decreased. In PB lymphocytes all studied genes were overexpressed. Higher expression of HIF-1A in PB lymphocytes of patients with abnormal spirometry, and in BALF cells of patients with lung volume restriction was found. VEGF gene expression in BALF cells was also higher in patients with abnormal spirometry. These findings were in line with previous data on the role of HIF-1A/VEGF/ING-4 axis in the pathogenesis of sarcoidosis. Up-regulated HIF-1A and VEGF genes are linked to acknowledged negative prognostics.

  11. Therapeutic angiogenesis due to balanced single-vector delivery of VEGF and PDGF-BB

    Science.gov (United States)

    Banfi, Andrea; von Degenfeld, Georges; Gianni-Barrera, Roberto; Reginato, Silvia; Merchant, Milton J.; McDonald, Donald M.; Blau, Helen M.

    2012-01-01

    Therapeutic angiogenesis by delivery of vascular growth factors is an attractive strategy for treating debilitating occlusive vascular diseases, yet clinical trials have thus far failed to show efficacy. As a result, limb amputation remains a common outcome for muscle ischemia due to severe atherosclerotic disease, with an overall incidence of 100 per million people in the United States per year. A challenge has been that the angiogenic master regulator vascular endothelial growth factor (VEGF) induces dysfunctional vessels, if expressed outside of a narrow dosage window. We tested the hypothesis that codelivery of platelet-derived growth factor-BB (PDGF-BB), which recruits pericytes, could induce normal angiogenesis in skeletal muscle irrespective of VEGF levels. Coexpression of VEGF and PDGF-BB encoded by separate vectors in different cells or in the same cells only partially corrected aberrant angiogenesis. In marked contrast, coexpression of both factors in every cell at a fixed relative level via a single bicistronic vector led to robust, uniformly normal angiogenesis, even when VEGF expression was high and heterogeneous. Notably, in an ischemic hindlimb model, single-vector expression led to efficient growth of collateral arteries, revascularization, increased blood flow, and reduced tissue damage. Furthermore, these results were confirmed in a clinically applicable gene therapy approach by adenoviral-mediated delivery of the bicistronic vector. We conclude that coordinated expression of VEGF and PDGF-BB via a single vector constitutes a novel strategy for harnessing the potency of VEGF to induce safe and efficacious angiogenesis.—Banfi, A., von Degenfeld, G., Gianni-Barrera, R., Reginato, S., Merchant, M. J., McDonald, D. M., Blau, H. M. Therapeutic angiogenesis due to balanced single-vector delivery of VEGF and PDGF-BB. PMID:22391130

  12. Experimental Anterior Ischemic Optic Neuropathy in Diabetic Mice Exhibited Severe Retinal Swelling Associated With VEGF Elevation.

    Science.gov (United States)

    Sun, Ming-Hui; Shariati, Mohammad Ali; Liao, Yaping Joyce

    2017-04-01

    Diabetes mellitus (DM) is one of the most important risk factors for nonarteritic anterior ischemic optic neuropathy (AION). In this study, we investigated for the first time the impact of experimental AION in a DM model. We induced a photochemical thrombosis model of AION after streptozotocin-induced DM and performed serial optical coherence tomography (OCT), morphometric analyses, and VEGF levels in the retina and sera. Compared with non-DM animals, experimental AION in DM mice led to significantly greater retinal swelling on day 1 and worse thinning at week 3 on OCT measurements. Greater retinal swelling on OCT in DM-AION eyes was associated with significantly increased loss of brain-specific homeobox/POU domain protein 3A (Brn3A+) retinal ganglion cells at week 3. In acute AION, there was greater inflammation as seen by an increase in ionized calcium-binding adapter molecule 1 (Iba1+)-activated microglia. On day 1, there was increase in vascular endothelial growth factor (VEGF) level in nondiabetic AION retinae and sera, but the VEGF level was the highest in the diabetic AION group, which decreased to nondiabetic levels after insulin treatment. The decrease in retinal and serum VEGF levels after insulin treatment correlated with a reduction in retinal swelling. In the setting of hyperglycemia, AION led to greater acute, postischemic microglial activation and elevation of VEGF levels, which likely contributed to greater retinal swelling acutely and worse retinal thinning and loss of retinal ganglion cells chronically. Treatment of hyperglycemia with insulin reduced VEGF levels and retinal swelling, consistent with the idea that VEGF is an important factor in postischemic swelling and that good glycemic control following AION may lead to better visual outcome.

  13. Ultrastrong trapping of VEGF by graphene oxide: Anti-angiogenesis application.

    Science.gov (United States)

    Lai, Pei-Xin; Chen, Chung-Wein; Wei, Shih-Chun; Lin, Tzu-Yu; Jian, Hong-Jyuan; Lai, Irving Po-Jung; Mao, Ju-Yi; Hsu, Pang-Hung; Lin, Han-Jia; Tzou, Wen-Shyong; Chen, Shiow-Yi; Harroun, Scott G; Lai, Jui-Yang; Huang, Chih-Ching

    2016-12-01

    Angiogenesis is the process of formation of new blood vessels, which is essential to human biology, and also plays a crucial role in several pathologies such as tumor growth and metastasis, exudative age-related macular degeneration, and ischemia. Vascular endothelial growth factor (VEGF), in particular, VEGF-A165 is the most important pro-angiogenic factor for angiogenesis. Thus, blocking the interaction between VEGFs and their receptors is considered an effective anti-angiogenic strategy. We demonstrate for that first time that bovine serum albumin-capped graphene oxide (BSA-GO) exhibits high stability in physiological saline solution and possesses ultrastrong binding affinity towards VEGF-A165 [dissociation constant (Kd) ∼3 × 10-12 M], which is at least five orders of magnitude stronger than that of high-abundant plasma proteins such as human serum albumin, fibrinogen, transferrin, and immunoglobulin G. Due to the surprising binding specificity of BSA-GO for VEGF-A165 in complex plasma fluid, we have also studied the anti-angiogenic effects in vitro and in vivo. Results show that BSA-GO not only effectively inhibits the proliferation, migration and tube formation of human umbilical vein endothelial cells, but also strongly disturbs the physiological process of angiogenesis in chick chorioallantoic membrane and blocks VEGF-A165-induced blood vessel formation in rabbit corneal neovascularization. Our findings indicate that GO nanomaterials can potentially act as therapeutic anti-angiogenic agents via ultrastrong VEGF adsorption and its activity suppression. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. SERUM CONCENTRATIONS OF SOME ANGIOGENEIC FACTORS IN MULTIPLE MYELOMA: VEGF, bFGF IN MMP-9

    Directory of Open Access Journals (Sweden)

    Mojca Modic

    2004-12-01

    Full Text Available Background. Angiogenesis is a crucial process in progression of multiple myeloma. Vascular endothelial growth factor (VEGF, and basic fibroblast growth factor (bFGF are multifunctional cytokines that stimulate angiogenesis and myeloma growth. Matrix metalloproteinase 9 (MMP-9 plays a critical role in osteolytic bone destruction, angiogenesis and invasive growth of myeloma cells. We evaluated serum concentrations of these factors in patients with multiple myeloma.Methods. Levels of active and pro-matrix metalloproteinase 9 (total MMP-9, basic fibroblast growth factor (bFGF and vascular endothelial growth factor (VEGF were determined with a commercial quantitative enzyme immunoassay Quantikine  (R&D Systems, USA. All of these factors were measured in the serum obtained from pheripheral blood of 36 patients affected by multiple myeloma.This series included 12 patients with disease in plateau phase and without treatment, 14 patients on Thalidomide therapy and 10 patients at the beginning of chemotherapy because of active disease.Results. VEGF showed a strong correlation with MMP-9 while VEGF and bFGF did not correlate with each other. Blood platelets correlated with VEGF and MMP-9.The concentration of MMP-9 and VEGF were the highest in group of patients with active disease where the chemotherapy started. The level of bFGF was the lowest in the group devoid of treatment (plateau phase of disease.Conclusions. Production of the angiogenic factors such as VEGF, bFGF and MMP-9 are increased in multiple myeloma patients. The levels of these factors correlate with the activity of disease.

  15. Binding of VEGF-A to canine cancer cells with preferential expression of VEGFR1

    Directory of Open Access Journals (Sweden)

    Antonella Borgatti,

    2014-01-01

    Full Text Available Aim: Despite encouraging results in syngeneic and xenografts cancer models with various inhibitors of vascular endothelial growth factor (VEGF or its receptors (VEGFRs, beneficial effects have not been consistently translated to the clinic, underscoring the need to develop strategies that go beyond the inhibition of these targets. The purpose of this study was to generate data to support the hypothesis that VEGF may be used as “bait” to selectively deliver therapeutics to VEGFR-expressing cancer cells. Materials and Methods: VEGFR1 and VEGFR2 expression was characterized using real time quantitative reverse transcriptase polymerase chain reaction (RT-qPCR in canine hemangiosarcoma (Grace-HSA, Emma-HSA, melanoma (TLM-1, and thyroid adenocarcinoma (CTAC cell lines. TLM-1 and Grace-HSA were identified as representative cell lines that selectively expressed high levels of VEGFR1. Flow cytometry was performed to examine binding of a single VEGF molecule (biotinylated VEGFA and avidin conjugated to fluorescein isothiocyanate (FITC by these chemoresistant cell lines. Results: RT-qPCR showed that canine tumor cells can preferentially express VEGFR1 over VEGFR2. Both TLM-1 and Grace-HSA cell lines, which represent VEGFR1-expressing tumors, showed specific binding to VEGF-A and this binding was competitively inhibited by anti-VEGF antibody. Conclusions: Cells preferentially expressing VEGFR1 can be targeted with a single VEGF molecule and these ligand-receptor pairs are well suited for targeting cytotoxic molecules in various canine tumor cells. Further studies are needed to develop strategies to selectively deliver therapeutics through VEGF-VEGFRs binding into VEGFR-expressing tumors.

  16. Corticosteroid suppression of VEGF-A in infantile hemangioma-derived stem cells.

    Science.gov (United States)

    Greenberger, Shoshana; Boscolo, Elisa; Adini, Irit; Mulliken, John B; Bischoff, Joyce

    2010-03-18

    Corticosteroids are commonly used to treat infantile hemangioma, but the mechanism of action of this therapy is unknown. We investigated the effect of corticosteroids in a previously described in vivo model of infantile hemangioma and in cultured hemangioma-derived cells. We tested hemangioma-derived stem cells for vasculogenic activity in vivo after implantation into immune-deficient (nude) mice. We studied dexamethasone treatment of both the cells before implantation and the mice after implantation. We also tested hemangioma-derived stem cells for expression of vascular endothelial growth factor A (VEGF-A) in vitro and studied the inhibition of VEGF-A expression, using short hairpin RNA (shRNA) in vivo and in vitro. Systemic treatment with dexamethasone led to dose-dependent inhibition of tumor vasculogenesis in the murine model. Pretreatment of hemangioma-derived stem cells in vitro before implantation also inhibited vasculogenesis. Dexamethasone suppressed VEGF-A production by hemangioma-derived stem cells in vitro but not by hemangioma-derived endothelial cells or human umbilical-vein endothelial cells. Silencing VEGF-A in hemangioma-derived stem cells reduced vasculogenesis in vivo. VEGF-A was detected in hemangioma specimens in the proliferating phase but not in the involuting phase and was shown by immunostaining to reside outside of vessels. Corticosteroid treatment suppressed other proangiogenic factors in hemangioma-derived stem cells, including urokinase plasminogen activator receptor, interleukin-6, monocyte chemoattractant protein 1, and matrix metalloproteinase 1. In a murine model, dexamethasone inhibited the vasculogenic potential of stem cells derived from human infantile hemangioma. The corticosteroid also inhibited the expression of VEGF-A by hemangioma-derived stem cells, and silencing of VEGF-A expression in these cells inhibited vasculogenesis in vivo. 2010 Massachusetts Medical Society

  17. An increase in vascular endothelial growth factor (VEGF and VEGF soluble receptor-1 (sFlt-1 are associated with early recurrent spontaneous abortion.

    Directory of Open Access Journals (Sweden)

    Lihong Pang

    Full Text Available Recurrent spontaneous abortion (RSA is a health problem that affects approximately 1% to 5% reproductive age woman. Yet, in around half of these patients, the mechanism for RSA is unexplained. Recent studies have indicated that placental ischemia/hypoxia and endothelial dysfunction are important factors in miscarriage. Other studies have indicated that the level and expression of soluble FMS-like tyrosine kinase-1 (sFlt1 is increased under a hypoxic environment. However, decreased sFlt-1 in the maternal circulation during the first trimester has recently been proposed as a potential marker for identifying risk of pregnancy loss. In this prospective study clinical samples were obtained within a short time after the fetal death, protein expression and maternal serum levels of sFlt1 were assessed and compared to samples taken from those with normal pregnancies. Our results indicate that levels of VEGF and sFlt-1 are both increased in women during early pregnancy compared women that are not pregnant (p<0.05 indicating that VEGF and sFlt-1 are both associated with pregnancy. More importantly, we detected a significant (p<0.05 increase in sFlt1 and VEGF levels and expression in the RSA patients who suffered subsequent miscarriages compare to controls. These results demonstrate that there is likely a relationship between VEGF, sFlt-1 and RSA suggesting that the high levels and over expression of sFlt-1 and VEGF might be associated with the pathogenesis of RSA.

  18. The correlation analysis of the expression of VEGF and the DCs’ infiltration density of gastric cancer tissues

    Institute of Scientific and Technical Information of China (English)

    Feng Yang; Ai-Mei Li; De-Huai Jing

    2016-01-01

    Objective:To investigate the correlation of the expression of vascular endothecial growth factor (VEGF) and the dendritic cells (DCs) infiltration density of tumor tissues in patients with gastric cancer and the correlation of the frequency of DCs of VEGF in gastric cancer tissues and the clinic stages; and to analyze the expressions of HLA-DR and CD86 on peripheral blood monocyte-derived DCs.Methods:Immuno fluorescence method was applied to test the expressions of CD11c and VEGF in gastric cancer tissues and para-carcinoma tissues and enzyme-linked immune sorbent assay was used to detect the concentration of serum VEGF. Peripheral blood mononuclear cells of the gastric cancer patients and healthy people were separated and induced DCs by GM-CSF and IL-4in vitro. Then, the expressions of HLA-DR and CD86 on DCs were tested by flow cytometry. Finally, the recombinant VEGF protein was added into DCs cultures to explore how VEGF affected the expression of CD86. Results: There was a negative correlation between the expression intensity of VEGF on gastric cancer cells and the tumor-infiltrating density of DCs; while there was a certain positive correlation between the frequency of DCs of VEGF and the development of the disease. The concentration of serum VEGF had no association with the density of tumor-infiltrating DCs. As for peripheral blood mononuclear cell, it had a certain induced effect on the decrease of DCs, the expressions of HLA-DR and CD86 and the expression of CD86 on DCs’ cell surface by VEGF.Conclusions:The activities of DCs were inhibited by VEGF secretion of gastric cancer tissues so as to mediate immune escape of the cancer cells. In addition, DCs infiltrated in gastric cancer tissues may secrete VEGF to participate the development of the disease.

  19. Long-lasting fibrin matrices ensure stable and functional angiogenesis by highly tunable, sustained delivery of recombinant VEGF164

    OpenAIRE

    Sacchi, Veronica; Mittermayr, Rainer; Hartinger, Joachim; Martino, Mikaël M.; Lorentz, Kristen M.; Wolbank, Susanne; Hofmann, Anna; Largo, Remo A.; Marschall, Jeffrey S.; Groppa, Elena; Gianni-Barrera, Roberto; Ehrbar, Martin; Hubbell, Jeffrey A.; Redl, Heinz; Banfi, Andrea

    2014-01-01

    Inducing the growth of new blood vessels by specific factors is an attractive strategy to restore blood flow in ischemic tissues. Vascular endothelial growth factor (VEGF) is the master regulator of angiogenesis, yet clinical trials of VEGF gene delivery failed. Major challenges include the need to control the tissue distribution of factor dose and the duration of expression. Here, we developed a highly tunable fibrin-based platform to precisely control the dose and duration of VEGF protein d...

  20. Prokaryotic Soluble Overexpression and Purification of Human VEGF165 by Fusion to a Maltose Binding Protein Tag.

    Directory of Open Access Journals (Sweden)

    Minh Tan Nguyen

    Full Text Available Human vascular endothelial growth factor (VEGF is a key regulator of angiogenesis and plays a central role in the process of tumor growth and metastatic dissemination. Escherichia coli is one of the most common expression systems used for the production of recombinant proteins; however, expression of human VEGF in E. coli has proven difficult because the E. coli-expressed VEGF tends to be misfolded and forms inclusion bodies, resulting in poor solubility. In this study, we successfully produced semi-preparative amounts of soluble bioactive human VEGF165 (hVEGF. We created seven N-terminal fusion tag constructs with hexahistidine (His6, thioredoxin (Trx, glutathione S-transferase (GST, maltose-binding protein (MBP, N-utilization substance protein A (NusA, human protein disulfide isomerase (PDI, and the b'a' domain of PDI (PDIb'a', and tested each construct for soluble overexpression in E. coli. We found that at 18°C, 92.8% of the MBP-tagged hVEGF to be soluble and that this tag significantly increased the protein's solubility. We successfully purified 0.8 mg of pure hVEGF per 500 mL cell culture. The purified hVEGF is stable after tag cleavage, contains very low levels of endotoxin, and is 97.6% pure. Using an Flk1+ mesodermal precursor cell (MPC differentiation assay, we show that the purified hVEGF is not only bioactive but has similar bioactivity to hVEGF produced in mammalian cells. Previous reports on producing hVEGF in E. coli have all been based on refolding of the protein from inclusion bodies. To our knowledge, this is the first report on successfully expressing and purifying soluble hVEGF in E. coli.

  1. The growth and aggressive behavior of human osteosarcoma is regulated by a CaMKII-controlled autocrine VEGF signaling mechanism.

    Directory of Open Access Journals (Sweden)

    Paul G Daft

    Full Text Available Osteosarcoma (OS is a hyperproliferative malignant tumor that requires a high vascular density to maintain its large volume. Vascular Endothelial Growth Factor (VEGF plays a crucial role in angiogenesis and acts as a paracrine and autocrine agent affecting both endothelial and tumor cells. The alpha-Ca2+/Calmodulin kinase two (α-CaMKII protein is an important regulator of OS growth. Here, we investigate the role of α-CaMKII-induced VEGF in the growth and tumorigenicity of OS. We show that the pharmacologic and genetic inhibition of α-CaMKII results in decreases in VEGF gene expression (50% and protein secretion (55%, while α- CaMKII overexpression increases VEGF gene expression (250% and protein secretion (1,200%. We show that aggressive OS cells (143B express high levels of VEGF receptor 2 (VEGFR-2 and respond to exogenous VEGF (100nm by increasing intracellular calcium (30%. This response is ameliorated by the VEGFR inhibitor CBO-P11, suggesting that secreted VEGF results in autocrine stimulated α-CaMKII activation. Furthermore, we show that VEGF and α-CaMKII inhibition decreases the transactivation of the HIF-1α and AP-1 reporter constructs. Additionally, chromatin immunoprecipitation assay shows significantly decreased binding of HIF-1α and AP-1 to their responsive elements in the VEGF promoter. These data suggest that α-CaMKII regulates VEGF transcription by controlling HIF-1α and AP-1 transcriptional activities. Finally, CBO-P11, KN-93 (CaMKII inhibitor and combination therapy significantly reduced tumor burden in vivo. Our results suggest that VEGF-induced OS tumor growth is controlled by CaMKII and dual therapy by CaMKII and VEGF inhibitors could be a promising therapy against this devastating adolescent disease.

  2. The growth and aggressive behavior of human osteosarcoma is regulated by a CaMKII-controlled autocrine VEGF signaling mechanism.

    Science.gov (United States)

    Daft, Paul G; Yang, Yang; Napierala, Dobrawa; Zayzafoon, Majd

    2015-01-01

    Osteosarcoma (OS) is a hyperproliferative malignant tumor that requires a high vascular density to maintain its large volume. Vascular Endothelial Growth Factor (VEGF) plays a crucial role in angiogenesis and acts as a paracrine and autocrine agent affecting both endothelial and tumor cells. The alpha-Ca2+/Calmodulin kinase two (α-CaMKII) protein is an important regulator of OS growth. Here, we investigate the role of α-CaMKII-induced VEGF in the growth and tumorigenicity of OS. We show that the pharmacologic and genetic inhibition of α-CaMKII results in decreases in VEGF gene expression (50%) and protein secretion (55%), while α- CaMKII overexpression increases VEGF gene expression (250%) and protein secretion (1,200%). We show that aggressive OS cells (143B) express high levels of VEGF receptor 2 (VEGFR-2) and respond to exogenous VEGF (100nm) by increasing intracellular calcium (30%). This response is ameliorated by the VEGFR inhibitor CBO-P11, suggesting that secreted VEGF results in autocrine stimulated α-CaMKII activation. Furthermore, we show that VEGF and α-CaMKII inhibition decreases the transactivation of the HIF-1α and AP-1 reporter constructs. Additionally, chromatin immunoprecipitation assay shows significantly decreased binding of HIF-1α and AP-1 to their responsive elements in the VEGF promoter. These data suggest that α-CaMKII regulates VEGF transcription by controlling HIF-1α and AP-1 transcriptional activities. Finally, CBO-P11, KN-93 (CaMKII inhibitor) and combination therapy significantly reduced tumor burden in vivo. Our results suggest that VEGF-induced OS tumor growth is controlled by CaMKII and dual therapy by CaMKII and VEGF inhibitors could be a promising therapy against this devastating adolescent disease.

  3. CCL5 promotes VEGF-C production and induces lymphangiogenesis by suppressing miR-507 in human chondrosarcoma cells.

    Science.gov (United States)

    Wang, Li-Hong; Lin, Chih-Yang; Liu, Shih-Chia; Liu, Guan-Ting; Chen, Yen-Ling; Chen, Jih-Jung; Chan, Chia-Han; Lin, Ting-Yi; Chen, Chi-Kuan; Xu, Guo-Hong; Chen, Shiou-Sheng; Tang, Chih-Hsin; Wang, Shih-Wei

    2016-06-14

    Chondrosarcoma is the second most frequently occurring type of bone malignancy that is characterized by the distant metastasis propensity. Vascular endothelial growth factor-C (VEGF-C) is the major lymphangiogenic factor, and makes crucial contributions to tumor lymphangiogenesis and lymphatic metastasis. Chemokine CCL5 has been reported to facilitate angiogenesis and metastasis in chondrosarcoma. However, the effect of chemokine CCL5 on VEGF-C regulation and lymphangiogenesis in chondrosarcoma has largely remained a mystery. In this study, we showed a clinical correlation between CCL5 and VEGF-C as well as tumor stage in human chondrosarcoma tissues. We further demonstrated that CCL5 promoted VEGF-C expression and secretion in human chondrosarcoma cells. The conditioned medium (CM) from CCL5-overexpressed cells significantly induced tube formation of human lymphatic endothelial cells (LECs). Mechanistic investigations showed that CCL5 activated VEGF-C-dependent lymphangiogenesis by down-regulating miR-507. Moreover, inhibiting CCL5 dramatically reduced VEGF-C and lymphangiogenesis in the chondrosarcoma xenograft animal model. Collectively, we document for the first time that CCL5 induces tumor lymphangiogenesis by the induction of VEGF-C in human cancer cells. Our present study reveals miR-507/VEGF-C signaling as a novel mechanism in CCL5-mediated tumor lymphangiogenesis. Targeting both CCL5 and VEGF-C pathways might serve as the potential therapeutic strategy to block cancer progression and metastasis in chondrosarcoma.

  4. VEGF-A isoform-specific regulation of calcium ion flux, transcriptional activation and endothelial cell migration

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    Gareth W. Fearnley

    2015-07-01

    Full Text Available Vascular endothelial growth factor A (VEGF-A regulates many aspects of vascular physiology such as cell migration, proliferation, tubulogenesis and cell-cell interactions. Numerous isoforms of VEGF-A exist but their physiological significance is unclear. Here we evaluated two different VEGF-A isoforms and discovered differential regulation of cytosolic calcium ion flux, transcription factor localisation and endothelial cell response. Analysis of VEGF-A isoform-specific stimulation of VEGFR2-dependent signal transduction revealed differential capabilities for isoform activation of multiple signal transduction pathways. VEGF-A165 treatment promoted increased phospholipase Cγ1 phosphorylation, which was proportional to the subsequent rise in cytosolic calcium ions, in comparison to cells treated with VEGF-A121. A major consequence of this VEGF-A isoform-specific calcium ion flux in endothelial cells is differential dephosphorylation and subsequent nuclear translocation of the transcription factor NFATc2. Using reverse genetics, we discovered that NFATc2 is functionally required for VEGF-A-stimulated endothelial cell migration but not tubulogenesis. This work presents a new mechanism for understanding how VEGF-A isoforms program complex cellular outputs by converting signal transduction pathways into transcription factor redistribution to the nucleus, as well as defining a novel role for NFATc2 in regulating the endothelial cell response.

  5. SLT-VEGF Reduces Lung Metastases, Decreases Tumor Recurrence, and Improves Survival in an Orthotopic Melanoma Model

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    Sini Skariah

    2010-08-01

    Full Text Available SLT-VEGF is a recombinant cytotoxin comprised of Shiga-like toxin (SLT subunit A fused to human vascular endothelial growth factor (VEGF. It is highly cytotoxic to tumor endothelial cells overexpressing VEGF receptor-2 (VEGFR-2/KDR/Flk1 and inhibits the growth of primary tumors in subcutaneous models of breast and prostate cancer and inhibits metastatic dissemination in orthotopic models of pancreatic cancer. We examined the efficacy of SLT-VEGF in limiting tumor growth and metastasis in an orthotopic melanoma model, using NCR athymic nude mice inoculated with highly metastatic Line IV Cl 1 cultured human melanoma cells. Twice weekly injections of SLT-VEGF were started when tumors became palpable at one week after intradermal injection of 1 × 106 cells/mouse. Despite selective depletion of VEGFR-2 overexpressing endothelial cells from the tumor vasculature, SLT-VEGF treatment did not affect tumor growth. However, after primary tumors were removed, continued SLT-VEGF treatment led to fewer tumor recurrences (p = 0.007, reduced the incidence of lung metastasis (p = 0.038, and improved survival (p = 0.002. These results suggest that SLT-VEGF is effective at the very early stages of tumor development, when selective killing of VEGFR-2 overexpressing endothelial cells can still prevent further progression. We hypothesize that SLT-VEGF could be a promising adjuvant therapy to inhibit or prevent outgrowth of metastatic foci after excision of aggressive primary melanoma lesions.

  6. Pure red cell aplasia induced by anti-erythropoietin antibodies, well-controlled with tacrolimus.

    Science.gov (United States)

    Hashimoto, Koji; Harada, Makoto; Kamijo, Yuji

    2016-10-01

    Anti-erythropoietin (anti-EPO) antibody-related pure red cell aplasia (PRCA) is a rare but serious complication that can occur during the administration of erythropoiesis-stimulating agents. Treatment with the calcineurin inhibitor cyclosporine has shown benefits in patients with anti-EPO PRCA. The efficacy of tacrolimus, another calcineurin inhibitor, in patients with anti-EPO PRCA has not been determined. The present report is the first our knowledge to describe the successful treatment of a patient with anti-EPO PRCA using tacrolimus. A 73-year-old man was markedly anemic 8 months after starting epoetin beta treatment. He was diagnosed with anti-EPO PRCA. Cyclosporine was started, but he experienced side effects. He was switched from cyclosporine to tacrolimus. No side effects were observed, and his anti-EPO PRCA was improved 6 months later, despite the persistence of anti-EPO antibodies. Tacrolimus was continued until the disappearance of the antibodies. Following the cessation of tacrolimus, PRCA did not relapse. Antibody remained detectable at the time of clinical remission, indicating that immunosuppressive therapy should be continued while monitoring the antibody titer. When the antibody titer decreases to the negative range, cessation of the immunosuppressive therapy does not result in disease relapse.

  7. Protective effect of erythropoietin on renal injury induced in rats by four weeks of exhaustive exercise.

    Science.gov (United States)

    Lin, Xixiu; Jiang, Chonghe; Luo, Ziqiang; Qu, Shulin

    2013-06-24

    The protective effect of Erythropoietin (EPO) analogue rHuEPO on acute renal injury induced by exhaustive exercise had been reported. The purpose of this study is to probe into the protective effect of EPO on chronic renal injury induced by repeated exhaustive exercise for four weeks. Eighty adult male Sprague-Dawley rats were used in this experiment. The animals were randomly allocated to one of four groups: control (C), exhaustive exercise test (ET), ET plus EPO pre-treatement (ET+EPO) and ET+EPO plus LY294002 pretreatment (ET+EPO+LY). Compared with the rats in control group, there was considerable damage in kidney cells in rats of ET group as revealed by histological and ultrastructural examinations. However, treatment with EPO during the training, the exhaustive running distance was significant increased (P protective effect of EPO on chronic renal injury induced by repeated exhaustive exercise was demonstrated in the present study. We proposed that the effect could be due to inhibiting the cell apoptosis and blocking the formation of interstitial fibrosis via activation of the PI3K/Akt pathway, thus plays role in the endogenous protection of the kidney injury.

  8. Long-term cadmium exposure induces anemia in rats through hypoinduction of erythropoietin in the kidneys

    Energy Technology Data Exchange (ETDEWEB)

    Horiguchi, Hyogo [Department of Public Health, Fukushima Medical College, Fukushima (Japan); Sato, Masao [Department of Biomolecular Sciences, Institute of Biomedical Sciences, Fukushima Medical College, Fukushima (Japan); Konno, Nobuhiro [Department of Public Health, Fukushima Medical College, Fukushima (Japan); Fukushima, Masaaki [Department of Public Health, Fukushima Medical College, Fukushima (Japan)

    1996-11-01

    Cadmium (Cd), a highly toxic heavy metal, is distributed widely in the general environment of today. The characteristic clinical manifestations of chronic Cd intoxication include renal proximal tubular dysfunction, general osteomalacia with severe pains, and anemia. We have recently reported that the serum level of erythropoietin (EPO) remained low despite the severe anemia in patients with Itai-itai disease, the most severe form of chronic Cd intoxication. In order to prove that the anemia observed in chronic Cd intoxication arises from low production of EPO in the kidneys following the renal injury, we administered Cd to rats for a long period and performed the analysis of EPO mRNA inducibility in the kidneys. The rats administered Cd for 6 and 9 months showed anemia with low levels of plasma EPO as well as biochemical and histological renal tubular damage, and also hypoinduction of EPO mRNA in the kidneys. The results indicate that chronic Cd intoxication causes anemia by disturbing the EPO-production capacity of renal cells. (orig.). With 4 figs., 4 tabs.

  9. Detection of erythropoietin misuse by the Athlete Biological Passport combined with reticulocyte percentage.

    Science.gov (United States)

    Bejder, Jacob; Aachmann-Andersen, Niels Jacob; Bonne, Thomas Christian; Olsen, Niels Vidiendal; Nordsborg, Nikolai Baastrup

    2016-10-01

    The sensitivity of the adaptive model of the Athlete Biological Passport (ABP) and reticulocyte percentage (ret%) in detection of recombinant human erythropoietin (rHuEPO) misuse was evaluated using both a long-term normal dose and a brief high dose treatment regime. Sixteen subjects received either 65 IU rHuEPO × kg(-1) every second day for two weeks (normal-dose), 390 IU rHuEPO × kg(-1) on three consecutive days (high-dose), or frequent placebo treatment for 13 days in a randomized, placebo-controlled, double-blind crossover design. Blood variables were measured 4, 11, and 25 days following treatment initiation. The ABP based on haemoglobin concentration ([Hb]) and OFF-hr score ([Hb] - 60 × √ret%) yielded atypical profiles following both normal-dose and high-dose treatment (0 %, 31 %, 13 % vs. 21 %, 33 %, 20 % at days 4, 11, and 25 after normal and high dose, respectively). Including ret% as a stand-alone marker for atypical blood profiles increased (P Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  10. Human fetal liver cells for regulated ex vivo erythropoietin gene therapy

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    Ebtisam El Filali

    2014-01-01

    Full Text Available Possible risks and lack of donor livers limit application of liver transplantation. Liver cell transplantation is, at this moment, not a feasible alternative because engraftment in the liver is poor. Furthermore, there is also shortage of cells suitable for transplantation. Fetal liver cells are able to proliferate in cell culture and could therefore present an alternative source of cells for transplantation. In this study, we investigated the utility of human fetal liver cells for therapeutic protein delivery. We transplanted human fetal liver cells in immunodeficient mice but were not able to detect engraftment of human hepatocytes. In contrast, transplantation of human adult hepatocytes led to detectable engraftment of hepatocytes in murine liver. Transplantation of fetal liver cells did lead to abundant reconstitution of murine liver with human endothelium, indicating that endothelial cells are the most promising cell type for ex vivo liver cell gene therapy. Human liver endothelial cells were subsequently transduced with a lentiviral autoregulatory erythropoietin expression vector. After transplantation in immunodeficient mice, these cells mediated long-term regulation of murine hematocrits. Our study shows the potential of human liver endothelial cells for long-term regulated gene therapy.

  11. The Effects of Erythropoietin Dose Titration during High-Fat Diet-Induced Obesity

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    Amanda Foskett

    2011-01-01

    Full Text Available Erythropoietin (Epo is a pleotropic cytokine with several nonhematopoietic tissue effects. High-dose Epo treatment-mediated effects on body weight, fat mass and glucose tolerance have recently been reported, thus extending its pleotropic effects to fat and glucose metabolism. However, the exact dose range of Epo treatment required for such effects remains unidentified to date. We investigated Epo dosage effect (up to 1000 U/kg on hematocrit, body weight, body composition, glucose metabolism, food intake, and physical activity, during high-fat diet-induced obesity. We report that Epo doses (1000, 600, 300, and 150 U/kg significantly reduced body weight gain and fat mass, while, only Epo doses of 300 U/kg and higher significantly affected glucose tolerance. None of the tested Epo doses showed any detectable effects on food intake, and only 1000 U/kg dose significantly increased physical activity, suggesting that these parameters may only be partially responsible for the metabolic effects of Epo treatment.

  12. High dose Erythropoietin increases Brain Tissue Oxygen Tension in Severe Vasospasm after Subarachnoid Hemorrhage

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    Helbok Raimund

    2012-06-01

    Full Text Available Abstract Background Vasospasm-related delayed cerebral ischemia (DCI significantly impacts on outcome after aneurysmal subarachnoid hemorrhage (SAH. Erythropoietin (EPO may reduce the severity of cerebral vasospasm and improve outcome, however, underlying mechanisms are incompletely understood. In this study, the authors aimed to investigate the effect of EPO on cerebral metabolism and brain tissue oxygen tension (PbtO2. Methods Seven consecutive poor grade SAH patients with multimodal neuromonitoring (MM received systemic EPO therapy (30.000 IU per day for 3 consecutive days for severe cerebral vasospasm. Cerebral perfusion pressure (CPP, mean arterial blood pressure (MAP, intracranial pressure (ICP, PbtO2 and brain metabolic changes were analyzed during the next 24 hours after each dose given. Statistical analysis was performed with a mixed effects model. Results A total of 22 interventions were analyzed. Median age was 47 years (32–68 and 86 % were female. Three patients (38 % developed DCI. MAP decreased 2 hours after intervention (P btO2 significantly increased over time (P  Conclusions EPO increases PbtO2 in poor grade SAH patients with severe cerebral vasospasm. The effect on outcome needs further investigation.

  13. Erythropoietin Slows Photoreceptor Cell Death in a Mouse Model of Autosomal Dominant Retinitis Pigmentosa.

    Science.gov (United States)

    Rex, Tonia S; Kasmala, Lorraine; Bond, Wesley S; de Lucas Cerrillo, Ana M; Wynn, Kristi; Lewin, Alfred S

    2016-01-01

    To test the efficacy of systemic gene delivery of a mutant form of erythropoietin (EPO-R76E) that has attenuated erythropoietic activity, in a mouse model of autosomal dominant retinitis pigmentosa. Ten-day old mice carrying one copy of human rhodopsin with the P23H mutation and both copies of wild-type mouse rhodopsin (hP23H RHO+/-,mRHO+/+) were injected into the quadriceps with recombinant adeno-associated virus (rAAV) carrying either enhanced green fluorescent protein (eGFP) or EpoR76E. Visual function (electroretinogram) and retina structure (optical coherence tomography, histology, and immunohistochemistry) were assessed at 7 and 12 months of age. The outer nuclear layer thickness decreased over time at a slower rate in rAAV.EpoR76E treated as compared to the rAAV.eGFP injected mice. There was a statistically significant preservation of the electroretinogram at 7, but not 12 months of age. Systemic EPO-R76E slows death of the photoreceptors and vision loss in hP23H RHO+/-,mRHO+/+ mice. Treatment with EPO-R76E may widen the therapeutic window for retinal degeneration patients by increasing the number of viable cells. Future studies might investigate if co-treatment with EPO-R76E and gene replacement therapy is more effective than gene replacement therapy alone.

  14. Evaluation of protein N-glycosylation in 2-DE: Erythropoietin as a study case.

    Science.gov (United States)

    Llop, Esther; Gallego, Ricardo Gutiérrez; Belalcazar, Viviana; Gerwig, Gerrit J; Kamerling, Johannis P; Segura, Jordi; Pascual, José A

    2007-12-01

    The structure, function, and physico-chemical properties of many proteins are determined by PTM, being glycosylation the most complex. This study describes how a combination of typical proteomics methods (2-DE) combines with glycomics strategies (HPLC, MALDI-TOF-MS, exoglycosidases sequencing) to yield comprehensive data about single spot-microheterogeneity, providing meaningful information for the detection of disease markers, pharmaceutical industry, antidoping control, etc. Recombinant erythropoietin and its hyperglycosylated analogue darbepoetin-alpha were chosen as showcases because of their relevance in these fields and the analytical challenge they represent. The combined approach yielded good results in terms of sample complexity (mixture glycoforms), reproducibility, sensitivity ( approximately 25 pmoles of glycoprotein/spot), and identification of the underlying protein. Heterogeneity was present in all spots but with a clear tendency; spots proximal to the anode contained the highest amount of tetra-antennary tetra-sialylated glycans, whereas the opposite occurred for spots proximal to the cathode with the majority of the structures being undersialylated. Spot microheterogeneity proved a consequence of the multiple glycosylation sites as they contributed directly to the number of possibilities to account for a discrete charge in a single spot. The interest of this combined glycoproteomics method resides in the efficiency for detecting and quantifying subtle dissimilarities originated from altered ratios of identical glycans including N-acetyl-lactosamine repeats, acetylation, or antigenic epitopes, that do not significantly contribute to the electrophoretic mobility, but affect the glycan microheterogeneity and the potential underlying related functionality.

  15. BET bromodomain inhibition rescues erythropoietin differentiation of human erythroleukemia cell line UT7

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    Goupille, Olivier [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France); Penglong, Tipparat [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France); Thalassemia Research Center and Department of Clinical Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University (Thailand); Lefevre, Carine; Granger, Marine; Kadri, Zahra [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France); Fucharoen, Suthat [Thalassemia Research Center and Department of Clinical Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University (Thailand); Maouche-Chretien, Leila [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France); Leboulch, Philippe [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France); Genetics Division, Department of Medicine, Brigham and Women' s Hospital and Harvard Medical School, Boston, MA (United States); Chretien, Stany, E-mail: stany.chretien@cea.fr [CEA, Institute of Emerging Diseases and Innovative Therapies, Fontenay-aux-Roses (France); UMR INSERM U.962, University Paris XI, CEA, Fontenay-aux-Roses (France)

    2012-12-07

    Highlights: Black-Right-Pointing-Pointer UT7 erythroleukemia cells are known to be refractory to differentiate. Black-Right-Pointing-Pointer Brief JQ1 treatment initiates the first steps of erythroid differentiation program. Black-Right-Pointing-Pointer Engaged UT7 cells then maturate in the presence of erythropoietin. Black-Right-Pointing-Pointer Sustained JQ1 treatment inhibits both proliferation and erythroid differentiation. -- Abstract: Malignant transformation is a multistep process requiring oncogenic activation, promoting cellular proliferation, frequently coupled to inhibition of terminal differentiation. Consequently, forcing the reengagement of terminal differentiation of transformed cells coupled or not with an inhibition of their proliferation is a putative therapeutic approach to counteracting tumorigenicity. UT7 is a human leukemic cell line able to grow in the presence of IL3, GM-CSF and Epo. This cell line has been widely used to study Epo-R/Epo signaling pathways but is a poor model for erythroid differentiation. We used the BET bromodomain inhibition drug JQ1 to target gene expression, including that of c-Myc. We have shown that only 2 days of JQ1 treatment was required to transitory inhibit Epo-induced UT7 proliferation and to restore terminal erythroid differentiation. This study highlights the importance of a cellular erythroid cycle break mediated by c-Myc inhibition before initiation of the erythropoiesis program and describes a new model for BET bromodomain inhibitor drug application.

  16. Effect of Autoantibodies to Erythropoietin Receptor in Systemic Lupus Erythematosus with Biopsy-proven Lupus Nephritis.

    Science.gov (United States)

    Hara, Akinori; Furuichi, Kengo; Yamahana, Junya; Yasuda, Haruka; Iwata, Yasunori; Sakai, Norihiko; Shimizu, Miho; Kaneko, Shuichi; Wada, Takashi

    2016-07-01

    We examined the clinical significance of autoantibodies to the erythropoietin receptor (EPOR) in patients with systemic lupus erythematosus (SLE) who had biopsy-proven lupus nephritis (LN). Forty-six Japanese patients with SLE with LN who had undergone renal biopsy during 1993-2014 were enrolled in this study and followed for a mean of 83 months. Sera from those patients were screened for anti-EPOR antibodies using ELISA. Anti-EPOR antibodies were detected in 18 (39%) of the 46 patients with SLE with anemia. Anti-EPOR antibodies were associated with low hemoglobin concentrations and reticulocytopenia. In addition, anti-EPOR antibodies were positively correlated with SLE disease activity, even though serum levels of the complement factors 3 and 4 did not differ between the 2 groups. In patients with International Society of Nephrology/Renal Pathology Society 2003 class IV LN, anti-EPOR antibodies were associated with active lesions including cellular crescents in glomeruli. Decrease in renal function was more frequently observed in patients without complete or partial renal response than in patients with it, and serum levels of the antibodies as well as renal response to treatment were significant risk factors for progression of renal dysfunction. The present study suggests that anti-EPOR antibodies might be involved in overall disease activity and active renal lesions, as well as in the impaired erythropoiesis in patients with SLE with LN. Further, the levels of anti-EPOR antibodies may be an additional predictor for renal injury.

  17. Potency Evaluation of Recombinant Human Erythropoietin in Brazil: Assessment of Reproducibility Using a Practical Approach

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    Michele Cardoso do Nascimento

    2015-08-01

    Full Text Available In this study, we compared the results of potency determination of recombinant human erythropoietin (rhEPO obtained between 2010 and 2012 by the National Institute of Quality Control in Health (INCQS/Fiocruz, i.e., the National Control Laboratory (NCL, and by a manufacturer of rhEPO. In total, 47 different batches of commercially prepared rhEPO (alpha isoform were analyzed. All results, including those of the control and warning limits, remained within the limits recommended by European Pharmacopoeia (Ph. Eur.. All relative error (RE values were less than ± 30%, wh ereas most were approximately ± 20%. Applying the Bland-Altman plot, only two of 47 values remained outside the limits of agreement (LA. In addition, agreement of potency determination between INCQS and the manufacturer coefficient of variation of reproducibility (% CVR was considered satisfactory. Taken together, our results demonstrate (i. the potency assay of rhEPO performed at INCQS, is standardized and controlled, (ii. the comparison of our results with those of the manufacturer, revealed an adequate inter-laboratory variation, and (iii. the critical appraisal proposed here appears to be a feasible tool to assess the reproducibility of biological activity, providing additional information regarding monitoring and production consistency to manufacturers and NCLs.

  18. Genistein attenuates hypoxic pulmonary hypertension via enhanced nitric oxide signaling and the erythropoietin system.

    Science.gov (United States)

    Kuriyama, Sachiko; Morio, Yoshiteru; Toba, Michie; Nagaoka, Tetsutaro; Takahashi, Fumiyuki; Iwakami, Shin-Ichiro; Seyama, Kuniaki; Takahashi, Kazuhisa

    2014-06-01

    Upregulation of the erythropoietin (EPO)/EPO receptor (EPOR) system plays a protective role against chronic hypoxia-induced pulmonary hypertension (hypoxic PH) through enhancement of endothelial nitric oxide (NO)-mediated signaling. Genistein (Gen), a phytoestrogen, is considered to ameliorate NO-mediated signaling. We hypothesized that Gen attenuates and prevents hypoxic PH. In vivo, Sprague-Dawley rats raised in a hypobaric chamber were treated with Gen (60 mkg/kg) for 21 days. Pulmonary hemodynamics and vascular remodeling were ameliorated in Gen-treated hypoxic PH rats. Gen also restored cGMP levels and phosphorylated endothelial NO synthase (p-eNOS) at Ser(1177) and p-Akt at Ser(473) expression in the lungs. Additionally, Gen potentiated plasma EPO concentration and EPOR-positive endothelial cell counts. In experiments with hypoxic PH rats' isolated perfused lungs, Gen caused NO- and phosphatidylinositol 3-kinase (PI3K)/Akt-dependent vasodilation that reversed abnormal vasoconstriction. In vitro, a combination of EPO and Gen increased the p-eNOS and the EPOR expression in human umbilical vein endothelial cells under a hypoxic environment. Moreover, Gen potentiated the hypoxic increase in EPO production from human hepatoma cells. We conclude that Gen may be effective for the prevention of hypoxic PH through the improvement of PI3K/Akt-dependent, NO-mediated signaling in association with enhancement of the EPO/EPOR system. Copyright © 2014 the American Physiological Society.

  19. Nitric oxide prevents axonal degeneration by inducing HIF-1-dependent expression of erythropoietin.

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    Keswani, Sanjay C; Bosch-Marcé, Marta; Reed, Nicole; Fischer, Angela; Semenza, Gregg L; Höke, Ahmet

    2011-03-22

    Nitric oxide (NO) is a signaling molecule that can trigger adaptive (physiological) or maladaptive (pathological) responses to stress stimuli in a context-dependent manner. We have previously reported that NO may signal axonal injury to neighboring glial cells. In this study, we show that mice deficient in neuronal nitric oxide synthase (nNOS-/-) are more vulnerable than WT mice to toxin-induced peripheral neuropathy. The administration of NO donors to primary dorsal root ganglion cultures prevents axonal degeneration induced by acrylamide in a dose-dependent manner. We demonstrate that NO-induced axonal protection is dependent on hypoxia-inducible factor (HIF)-1-mediated transcription of erythropoietin (EPO) within glial (Schwann) cells present in the cultures. Transduction of Schwann cells with adenovirus AdCA5 encoding a constitutively active form of HIF-1α results in amelioration of acrylamide-induced axonal degeneration in an EPO-dependent manner. Mice that are partially deficient in HIF-1α (HIF-1α+/-) are also more susceptible than WT littermates to toxic neuropathy. Our results indicate that NO→HIF-1→EPO signaling represents an adaptive mechanism that protects against axonal degeneration.

  20. Up-regulation of erythropoietin receptor by nitric oxide mediates hypoxia preconditioning.

    Science.gov (United States)

    Chen, Zhi-Yong; Wang, Li; Asavaritkrai, Pundit; Noguchi, Constance Tom

    2010-11-01

    Erythropoietin (Epo), known to stimulate erythroid progenitor cell survival, proliferation, and differentiation, has been shown to be neuroprotective against brain ischemia in animal models. Both Epo and Epo receptor (EpoR) are expressed in the brain and are up-regulated by hypoxia. Brain Epo signaling can stimulate neural cell survival and prevent neuron apoptosis. Neurons from EpoR null mice exhibit marked increased sensitivity to hypoxia. In endothelial cells, Epo has been shown to stimulate nitric oxide (NO) production, particularly at low pO(2). We found here that the EpoR expression on neural cells and Epo's neuroprotective effect were regulated by NO. Hypoxia increased NO production as well as EpoR expression, and inhibition of NOS activity reduced the proportion of EpoR-expressing neurons induced at low pO(2). Conversely, addition of NO donor to cultures grown under normoxia induced EpoR. Similarly, NO donor increased EpoR promoter activity in a reporter gene assay, suggesting that NO regulates EpoR at the transcription level. Preincubation of neurons with NO results in induction of EpoR, which gives rise to protection against hypoxia even in the absence of exogenous Epo, although at high concentration NO is toxic. These data provide evidence of a role for NO in Epo activity in brain and suggest links between NO production, EpoR expression, and Epo signaling in neuroprotection.

  1. Association between high-dose erythropoiesis-stimulating agents, inflammatory biomarkers, and soluble erythropoietin receptors

    Directory of Open Access Journals (Sweden)

    Inrig Jula K

    2011-12-01

    Full Text Available Abstract Background High-dose erythropoiesis-stimulating agents (ESA for anemia of chronic kidney disease (CKD have been associated with adverse clinical outcomes and do not always improve erythropoiesis. We hypothesized that high-dose ESA requirement would be associated with elevated inflammatory biomarkers, decreased adipokines, and increased circulating, endogenous soluble erythropoietin receptors (sEpoR. Methods A cross-sectional cohort of anemic 32 CKD participants receiving ESA were enrolled at a single center and cytokine profiles, adipokines, and sEpoR were compared between participants stratified by ESA dose requirement (usual-dose darbepoetin-α ( Results Baseline characteristics were similar between groups; however, hemoglobin was lower among participants on high-dose (1.4 μg/kg/week vs usual-dose (0.5 μg/kg/week ESA. In adjusted analyses, high-dose ESA was associated with an increased odds for elevations in c-reactive protein and interleukin-6 (p s = 0.39, p = 0.03. In adjusted analyses, higher ESA dose (per μcg/kg/week was associated with a 53% greater odds of sEpoR being above the median (p Conclusion High-dose ESA requirement among anemic CKD participants was associated with elevated inflammatory biomarkers and higher levels of circulating sEpoR, an inhibitor of erythropoiesis. Further research confirming these findings is warranted. Trial registration Clinicaltrials.gov NCT00526747

  2. Epidermal growth factor and erythropoietin infusion accelerate functional recovery in combination with rehabilitation.

    Science.gov (United States)

    Jeffers, Matthew S; Hoyles, Amy; Morshead, Cindi; Corbett, Dale

    2014-06-01

    Rehabilitation is the only treatment option for chronic stroke deficits, but unfortunately, it often provides incomplete recovery. In this study, a novel combination of growth factor administration and rehabilitation therapy was used to facilitate functional recovery in a rat model of cortical stroke. Ischemia was induced via injection of endothelin-1 into the sensorimotor cortex. This was followed by either a 2-week infusion of epidermal growth factor and erythropoietin or artificial cerebrospinal fluid into the ipsilateral lateral ventricle. Two weeks after ischemia, animals began an 8-week enriched rehabilitation program. Functional recovery was assessed after ischemia using the Montoya staircase-reaching task, beam-traversing, and cylinder test of forelimb asymmetry. The combination of growth factor infusion and rehabilitation led to a significant acceleration in recovery in the staircase task. When compared with controls, animals receiving the combination treatment attained significant recovery of function at 4 weeks after stroke, whereas those receiving rehabilitation alone did not recover until 10 weeks. Significant recovery was also observed on the beam-traversing and cylinder tasks. Combining behavioral rehabilitation with growth factor infusion accelerates motor recovery. These data suggest a promising new avenue of combination therapies that may have the potential to reduce the rehabilitation time necessary to recover from sensorimotor deficits arising from stroke. © 2014 American Heart Association, Inc.

  3. Erythropoietin protects epithelial cells from excessive autophagy and apoptosis in experimental neonatal necrotizing enterocolitis.

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    Yueyue Yu

    Full Text Available Neonatal necrotizing enterocolitis (NEC is a devastating gastrointestinal disease of preterm infants. Increased intestinal epithelium permeability is an early event in NEC pathogenesis. Autophagy and apoptosis are induced by multiple stress pathways which may impact the intestinal barrier, and they have been associated with pathogenesis of diverse gastrointestinal diseases including inflammatory bowel disease. Using both in vitro and in vivo models, this study investigates autophagy and apoptosis under experimental NEC stresses. Furthermore this study evaluates the effect of erythropoietin (Epo, a component of breast milk previously shown to decrease the incidence of NEC and to preserve intestinal barrier function, on intestinal autophagy and apoptosis. It was found that autophagy and apoptosis are both rapidly up regulated in NEC in vivo as indicated by increased expression of the autophagy markers Beclin 1 and LC3II, and by evidence of apoptosis by TUNEL and cleaved caspase-3 staining. In the rat NEC experimental model, autophagy preceded the onset of apoptosis in intestine. In vitro studies suggested that Epo supplementation significantly decreased both autophagy and apoptosis via the Akt/mTOR signaling pathway and the MAPK/ERK pathway respectively. These results suggest that Epo protects intestinal epithelium from excessive autophagy and apoptosis in experimental NEC.

  4. PRAS40 is an integral regulatory component of erythropoietin mTOR signaling and cytoprotection.

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    Zhao Zhong Chong

    Full Text Available Emerging strategies that center upon the mammalian target of rapamycin (mTOR signaling for neurodegenerative disorders may bring effective treatment for a number of difficult disease entities. Here we show that erythropoietin (EPO, a novel agent for nervous system disorders, prevents apoptotic SH-SY5Y cell injury in an oxidative stress model of oxygen-glucose deprivation through phosphatidylinositol-3-kinase (PI 3-K/protein kinase B (Akt dependent activation of mTOR signaling and phosphorylation of the downstream pathways of p70 ribosomal S6 kinase (p70S6K, eukaryotic initiation factor 4E-binding protein 1 (4EBP1, and proline rich Akt substrate 40 kDa (PRAS40. PRAS40 is an important regulatory component either alone or in conjunction with EPO signal transduction that can determine cell survival through apoptotic caspase 3 activation. EPO and the PI 3-K/Akt pathways control cell survival and mTOR activity through the inhibitory post-translational phosphorylation of PRAS40 that leads to subcellular binding of PRAS40 to the cytoplasmic docking protein 14-3-3. However, modulation and phosphorylation of PRAS40 is independent of other protective pathways of EPO that involve extracellular signal related kinase (ERK 1/2 and signal transducer and activator of transcription (STAT5. Our studies highlight EPO and PRAS40 signaling in the mTOR pathway as potential therapeutic strategies for development against degenerative disorders that lead to cell demise.

  5. Erythropoietin Exacerbates Inflammation and Increases the Mortality of Histoplasma capsulatum-Infected Mice

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    Gisele Aparecida Locachevic

    2015-01-01

    Full Text Available Erythropoietin (EPO is a key hormone involved in red blood cell formation, but its effects on nonerythroid cells, such as macrophages, have not been described. Macrophages are key cells in controlling histoplasmosis, a fungal infection caused by Histoplasma capsulatum (Hc. Considering that little is known about EPO’s role during fungal infections and its capacity to activate macrophages, in this study we investigated the impact of EPO pretreatment on the alveolar immune response during Hc infection. The consequence of EPO pretreatment on fungal infection was determined by evaluating animal survival, fungal burden, activation of bronchoalveolar macrophages, inflammatory mediator release, and lung inflammation. Pretreatment with EPO diminished mononuclear cell numbers, increased the recruitment of F4/80+/CD80+ and F4/80+/CD86+ cells to the bronchoalveolar space, induced higher production of IFN-γ, IL-6, MIP-1α, MCP-1, and LTB4, reduced PGE2 concentration, and did not affect fungal burden. As a consequence, we observed an increase in lung inflammation with extensive tissue damage that might account for augmented mouse mortality after infection. Our results demonstrate for the first time that EPO treatment has a deleterious impact on lung immune responses during fungal infection.

  6. Evaluation of the effect of pentoxifylline on erythropoietin-resistant anemia in hemodialysis patients

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    Amir-Hooshang Mohammadpour

    2014-01-01

    Full Text Available Use of recombinant human erythropoietin (rh-Epo improves hemoglobin (Hgb in 90-95% of the cases of anemia of chronic kidney disease (CKD. However, it is known that pro-inflammatory cytokines such as interferon-gamma (IFN-γ, tumor necrosis factor-alfa (TNF-α and interleukin-1 (IL-1 suppress erythropoiesis, resulting in inadequate response to rh-Epo. Pentoxifylline has been shown to have modulatory effects on the immune system. This prospec-tive study to evaluate the effect of pentoxyphylline on erythropoeisis was performed on 15 (eight males, seven females clinically stable patients who had been on hemodialysis for at least six months with anemia (Hgb of <10.7 g/dL unresponsive to rh-Epo despite high doses. They were treated with 400 mg pentoxifylline tablets once daily for 12 weeks. Hgb increased after one and two months of drug administration, but significant changes were observed in eight (53% patients after three months (P <0.05. Our study illustrates a probable new use for an old medicine. Three months treatment with pentoxifylline was seen to increase Hgb significantly in rh-Epo-resistant patients. More prospective studies with a larger sample size are needed to determine the inhi-bitory role of cytokines on hematopoiesis and exploring new drugs or new drug indications to overcome anemia in advanced renal failure.

  7. DNA methylation is necessary for erythropoietin to improve spatial learning and memory in SAMP8 mice.

    Science.gov (United States)

    Yu, Nengwei; Liu, Jie; Yi, Gang; Ye, Fang; Xiao, Jun; Guo, Fuqiang

    2015-09-01

    To reveal the role of Dnmts in the improvement of spatial learning and memory induced by erythropoietin (EPO) in SAMP8 mice. The Morris water maze (MWM) was used to assess spatial learning and memory. Mice were administered by intraperitoneal (i.p.) injection of recombinant human EPO and hippocamppi infusion (IH) of 5-aza-2'-deoxycytidine (5-AZA). The expression of genes Dnmt1, Dnmt3a and Dnmt3b in the hippocampus was detected by real-time qPCR. The level of proteins DNMT1, DNMT3A and DNMT3B was measured by Western blotting. Spatial learning and memory in SAMP8 were promoted after i.p. injection of EPO (5000IU/kg/day) and expression of Dnmt3b mRNA and DNMT3B proteins in the hippocampus increased. The improved memory by EPO was blocked after IH 5-AZA. DNA methylation is necessary for EPO to enhance spatial learning and memory in SAMP8 mice. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Increased Urinary Erythropoietin Excretion in Severe Sleep Apnea-Hipoapnea Syndrome: The Effect of CPAP.

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    Félez, Miquel; Grau, Nuria; Ruiz, Antonia; Guardiola, Encarna; Sanjuas, Carles; Estirado, Cristina; Navarro-Muñoz, Maribel; Pascual, Antoni; Orozco-Levi, Mauricio; Gea, Joaquim

    2017-12-04

    Tissue hypoxia stimulates the production of erythropoietin (EPO), the main effect of which is, in turn, to stimulate erythropoiesis. Sleep apnea-hypopnea syndrome (SAHS) is an entity characterized by repeated episodes of hypoxemia during sleep. To analyze whether hypoxemia stimulated increased urinary excretion of EPO, and if so, to evaluate if treatment with continuous positive airway pressure (CPAP) can inhibit this phenomenon. We studied 25 subjects with suspected SAHS who underwent a polysomnography study (PSG). EPO levels in first morning urine (uEPO) and blood creatinine and hemoglobin were determined in all patients. Patients with severe SAHS repeated the same determinations after CPAP treatment. Twelve subjects were diagnosed with severe SAHS (mean ± SD, AHI 53.1 ± 22.7). Creatinine and hemoglobin levels were normal in all subjects. uEPO was 4 times higher in the SAHS group than in the control group (1.32 ± 0.83 vs. 0.32 ± 0.35 UI/l, p <.002). CPAP treatment reduced uEPO to 0.61 ± 0.9 UI/l (p <.02), levels close to those observed in healthy subjects. No dose-response relationship was observed between severity of PSG changes and uEPO values. Patients with severe SAHS show increased uEPO excretion, but this normalizes after treatment with CPAP. Copyright © 2017 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Human recombinant erythropoietin reduces sensorimotor dysfunction and cognitive impairment in rat models of chronic kidney disease.

    Science.gov (United States)

    Reza-Zaldívar, E E; Sandoval-Avila, S; Gutiérrez-Mercado, Y K; Vázquez-Méndez, E; Canales-Aguirre, A A; Esquivel-Solís, H; Gómez-Pinedo, U; Márquez-Aguirre, A L

    2017-11-10

    Chronic kidney disease (CKD) can cause anaemia and neurological disorders. Recombinant human erythropoietin (rHuEPO) is used to manage anaemia in CKD. However, there is little evidence on the effects of rHuEPO on behaviour and cognitive function in CKD. This study aimed to evaluate the impact of rHuEPO in sensorimotor and cognitive functions in a CKD model. Male Wistar rats were randomly assigned to 4 groups: control and CKD, with and without rHuEPO treatment (1050 IU per kg body weight, once weekly for 4 weeks). The Morris water maze, open field, and adhesive removal tests were performed simultaneously to kidney damage induction and treatment. Markers of anaemia and renal function were measured at the end of the study. Treatment with rHuEPO reduced kidney damage and corrected anaemia in rats with CKD. We observed reduced sensorimotor dysfunction in animals with CKD and treated with rHuEPO. These rats also completed the water maze test in a shorter time than the control groups. rHuEPO reduces kidney damage, corrects anemia, and reduces sensorimotor and cognitive dysfunction in animals with CKD. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Optimization of amino acid-stabilized erythropoietin parenteral formulation: In vitro and in vivo assessment

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    Fayed Bahgat E.

    2016-03-01

    Full Text Available The aim of this study was to optimize the formulation of erythropoietin (EPO using amino acids instead of human serum albumin (HSA and to evaluate its in vivo stability in order to avoid the risk of viral contamination and antigenicity. Different EPO formulations were developed in such a way as to allow studying the effects of amino acids and surfactants on the EPO stability profile. The main techniques applied for EPO analysis were ELISA, Bradford method, and SDS gel electrophoresis. The in vivo stability was evaluated in a Balb-c mouse animal model. The results showed that the presence of surfactant was very useful in preventing the initial adsorption of EPO on the walls of vials and in minimizing protein aggregation. Amino acid combinations, glycine with glutamic acid, provided maximum stability. Formulation F4 (containing glycine, glutamic acid and Tween 20 showed minimum aggregation and degradation and in vivo activity equivalent to commercially available HSA-stabilized EPO (Eprex®.

  11. Erythropoietin-coated ZP-microneedle transdermal system: preclinical formulation, stability, and delivery.

    Science.gov (United States)

    Peters, Elaine E; Ameri, Mahmoud; Wang, Xiaomei; Maa, Yuh-Fun; Daddona, Peter E

    2012-06-01

    To evaluate the feasibility of coating formulated recombinant human erythropoietin alfa (EPO) on a titanium microneedle transdermal delivery system, ZP-EPO, and assess preclinical patch delivery performance. Formulation rheology and surface activity were assessed by viscometry and contact angle measurement. EPO liquid formulation was coated onto titanium microneedles by dip-coating and drying. Stability of coated EPO was assessed by SEC-HPLC, CZE and potency assay. Preclinical in vivo delivery and pharmacokinetic studies were conducted in rats with EPO-coated microneedle patches and compared to subcutaneous EPO injection. Studies demonstrated successful EPO formulation development and coating on microneedle arrays. ZP-EPO patch was stable at 25°C for at least 3 months with no significant change in % aggregates, isoforms, or potency. Preclinical studies in rats showed the ZP-EPO microneedle patches, coated with 750 IU to 22,000 IU, delivered with high efficiency (75-90%) with a linear dose response. PK profile was similar to subcutaneous injection of commercial EPO. Results suggest transdermal microneedle patch delivery of EPO is feasible and may offer an efficient, dose-adjustable, patient-friendly alternative to current intravenous or subcutaneous routes of administration.

  12. Erythropoietin Promotes Neural Plasticity and Spatial Memory Recovery in Fimbria-Fornix-Lesioned Rats.

    Science.gov (United States)

    Almaguer-Melian, William; Mercerón-Martínez, Daymara; Pavón-Fuentes, Nancy; Alberti-Amador, Esteban; Leon-Martinez, Rilda; Ledón, Nuris; Delgado Ocaña, Susana; Bergado Rosado, Jorge A

    2015-01-01

    Erythropoietin (EPO) upregulates the mitogen activated protein kinase (MAPK) cascade, a central signaling pathway in cellular plastic mechanisms, and is critical for normal brain development. We hypothesized that EPO could modulate the plasticity mechanisms supporting spatial memory recovery in fimbria-fornix-transected animals. Fimbria-fornix was transected in 3 groups of rats. Seven days later, EPO was injected daily for 4 consecutive days within 10 minutes after training on a water maze task. Our results show that EPO injections 10 minutes after training produced a substantial spatial memory recovery in fimbria-fornix-lesioned animals. In contrast, an EPO injection shortly after fimbria-fornix lesion surgery does not promote spatial-memory recovery. Neither does daily EPO injection 5 hours after the water maze performance. EPO, on the other hand, induced the expression of plasticity-related genes like arc and bdnf, but this effect was independent of training or lesion. This finding supports our working hypothesis that EPO can modulate transient neuroplastic mechanisms triggered by training in lesioned animals. Consequently, we propose that EPO administration can be a useful trophic factor to promote neural restoration when given in combination with training. © The Author(s) 2015.

  13. The effects of erythropoietin dose titration during high-fat diet-induced obesity.

    Science.gov (United States)

    Foskett, Amanda; Alnaeeli, Mawadda; Wang, Li; Teng, Ruifeng; Noguchi, Constance T

    2011-01-01

    Erythropoietin (Epo) is a pleotropic cytokine with several nonhematopoietic tissue effects. High-dose Epo treatment-mediated effects on body weight, fat mass and glucose tolerance have recently been reported, thus extending its pleotropic effects to fat and glucose metabolism. However, the exact dose range of Epo treatment required for such effects remains unidentified to date. We investigated Epo dosage effect (up to 1000 U/kg) on hematocrit, body weight, body composition, glucose metabolism, food intake, and physical activity, during high-fat diet-induced obesity. We report that Epo doses (1000, 600, 300, and 150 U/kg) significantly reduced body weight gain and fat mass, while, only Epo doses of 300 U/kg and higher significantly affected glucose tolerance. None of the tested Epo doses showed any detectable effects on food intake, and only 1000 U/kg dose significantly increased physical activity, suggesting that these parameters may only be partially responsible for the metabolic effects of Epo treatment.

  14. Erythropoietin-Derived Peptide Protects Against Acute Lung Injury After Rat Traumatic Brain Injury

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    Yuan Liu

    2017-04-01

    Full Text Available Background: Traumatic brain injury (TBI can be complicated by TBI-triggered acute lung injury (ALI, in which inflammation plays a central role. It has been reported that an Erythropoietin-derived peptide (pHBSP was able to ameliorate TBI; however, its function in TBI-caused ALI has not been reported yet. Methods: In this study, we studied the effect of pHBSP on TBI-caused ALI by using a weight-drop induced TBI model. At 8 h and 24 h post-TBI, pulmonary edema (PE and bronchoalveolar lavage fluid (BALF proteins were measured, and haematoxylin and eosin (H&E staining of lung sections was carried out. At 24 h following TBI, the lungs were harvested for immunofluorescence staining and qRT-PCR analysis. Results: At 8 h and 24 h post-TBI, pHBSP treatment significantly decreased wet/dry ratios, decreased total BALF protein, and attenuated the histological signs of pulmonary injury. At 24 h post-TBI, pHBSP treatment decreased the accumulation of CD68+ macrophages in the lung and reduced the mRNA levels of TNF-α, IL-6, IL-1β and iNOS in the lung. Conclusions: We identified the protective role that pHBSP played in TBI-caused ALI, suggesting that pHBSP is a potent candidate for systemic therapy in TBI patients.

  15. Vector-mediated expression of erythropoietin improves functional outcome after cervical spinal cord contusion injury.

    Science.gov (United States)

    Wang, S; Wu, Z; Chiang, P; Fink, D J; Mata, M

    2012-09-01

    We evaluated the therapeutic effect of erythropoietin (EPO) delivered by direct injection of a nonreplicating herpes simplex virus (HSV)-based vector coding for EPO (vEPO) in a model of cervical hemicord contusion at C7. At 1 h after spinal cord injury (SCI), either vEPO or control vector carrying a reporter gene (vC) was injected into the cord above and below the lesion. Animals injected with vEPO showed a statistically significant improvement in the ipsilateral forelimb function, as measured by open-field evaluation of motor performance, forelimb reaching in the cylinder test and misplacement in grid walk. This correlated with preservation of gray matter in the area of the lesion. There was also mild but significant improvement of hindlimb motor function measured by Basso-Beattie-Bresnahan score and computerized gait analysis in vEPO compared with control vector-injected animals. Microtubule-associated protein tau, phosphorylated and nonphosphorylated neurofilament protein and the synaptic proteins synaptophysin and PSD-95 were all significantly increased in the spinal cord of vEPO-treated animals compared with control vector-injected animals. These data suggest that gene transfer of EPO after cervical SCI by minimizing the injury size and enhancing tissue sparing preserves large-caliber axons and promotes synaptogenesis.

  16. Erythropoietin, 2,3 DPG, oxygen transport capacity, and altitude training in adolescent Alpine skiers.

    Science.gov (United States)

    Son, Hee Jeong; Kim, Hyo Jeong; Kim, Jin Hae; Ohno, Hideki; Kim, Chang Keun

    2012-01-01

    Rapid growth during adolescence caused by metabolic changes and their metabolic response to anaerobic and aerobic exercise differs considerably from that in adults and this is especially true in the responses to stresses, such as altitude exposure. However, there is little information on the suitability of exercise training at altitude for young athletes. Six male Korean adolescent alpine skiers (13-17 yr), with a skiing career of 3-5 yr, participated in the study. All subjects were exposed to an altitude of 2700 m (8858 ft) for 5 wk and altitude exposure consisted of 6 d/wk of training (4-5 h/d), with living quarters at 2100 m (-6890 ft) (Tignes, France). The 5 wk of ski training at altitude were maintained at the same level (the same number of slalom and giant slalom skiing trials) as at sea level. There was a significant increase in oxygen transport capacity, despite decreased erythropoietin (EPO) production (-31%) after altitude training. Red blood cell (RBC), hemoglobin (Hb), hematocrit (Hct), and 2,3 DPG concentrations increased significantly during altitude exposure and after return to sea level. Results indicate that applying altitude training in adolescent skiers may improve their endurance performance. However, EPO production during altitude training needs to be evaluated in larger future studies.

  17. In silico design and analysis of a new hyperglycosylated analog of erythropoietin to improve drug efficacy.

    Science.gov (United States)

    Kianmehr, Anvarsadat; Mohammadi, Hamid Shahbaz; Shokrgozar, Mohammad Ali; Omidinia, Eskandar

    2015-01-01

    The enhancement of glycosylation by applying glycoengineering approaches has become widely used to boost properties for protein therapeutics. The objective of this work was to engineer a new hyperglycosylated analog of erythropoietin (EPO) with appropriately targeted N-linked carbohydrates through bioinformatics tools. The EPO protein sequence was retrieved from NCBI protein sequence database. Prediction of N-glycosylation sites for the target protein was done using the prediction server, NetNGlyc. The three-dimensional model of glycoengineered EPO (named as kypoetin) was constructed using the homology modeling program. Ramchandran plot obtained from PROCHECK server was used to check stereochemical property. Meanwhile, 3D model of kypoetin with attached N-carbohydrates was built up using the GlyProt server. In the new modified analog, three additional N-glycosylation sites at amino-acid positions 30, 34 and 86 were inserted. Ramchandran plot analysis showed 81.6% of the residues in the most favored region, 15.6% in the additional allowed, 1.4% in the generously allowed regions and 1.4% in the disallowed region. 3D structural modeling showed that attached carbohydrates were on the proper spatial position. The whole solvent accessible surface areas of kypoetin (15132.69) were higher than EPO (9938.62). Totally, various model evaluation methods indicated that the glycoengineered version of EPO had considerably good geometry and acceptable profiles for clinical studies and could be considered as the effective drug.

  18. Neuronal erythropoietin overexpression protects mice against age-related hearing loss (presbycusis).

    Science.gov (United States)

    Monge Naldi, Arianne; Belfrage, Celina; Jain, Neha; Wei, Eric T; Canto Martorell, Belén; Gassmann, Max; Vogel, Johannes

    2015-12-01

    So far, typical causes of presbycusis such as degeneration of hair cells and/or primary auditory (spiral ganglion) neurons cannot be treated. Because erythropoietin's (Epo) neuroprotective potential has been shown previously, we determined hearing thresholds of juvenile and aged mice overexpressing Epo in neuronal tissues. Behavioral audiometry revealed in contrast to 5 months of age, that 11-month-old Epo-transgenic mice had up to 35 dB lower hearing thresholds between 1.4 and 32 kHz, and at the highest frequencies (50-80 kHz), thresholds could be obtained in aged Epo-transgenic only but not anymore in old C57BL6 control mice. Click-evoked auditory brainstem response showed similar results. Numbers of spiral ganglion neurons in aged C57BL6 but not Epo-transgenic mice were dramatically reduced mainly in the basal turn, the location of high frequencies. In addition, there was a tendency to better preservation of inner and outer hair cells in Epo-transgenic mice. Hence, Epo's known neuroprotective action effectively suppresses the loss of spiral ganglion cells and probably also hair cells and, thus, development of presbycusis in mice. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Erythropoietin ameliorates the motor and cognitive function impairments in a rat model of hepatic cirrhosis.

    Science.gov (United States)

    Aghaei, Iraj; Nazeri, Masoud; Shabani, Mohammad; Mossavinasab, Marziehsadat; Mirhosseini, Fatemeh Khaleghi; Nayebpour, Mohsen; Dalili, Afshin

    2015-02-01

    Hepatic encephalopathy (HE) is a serious consequence of hepatic cirrhosis (HC). Previous studies have demonstrated cognitive impairments in both clinical and animal experiments of HC. Some potential therapeutic agents have been used to alleviate the cognitive symptoms in the animal models of HC. In the current study, the possible effect of erythropoietin (ERY) as a potent neuroprotective agent on motor and cognitive impairments induced by HC has been studied. Male Wistar rats (180-200 g) underwent bile duct ligation (BDL) or sham surgery. Administration of ERY (5,000 IU/kg, i.p., daily for three days) was initiated 2 weeks after surgery and lasted for the next 28 days. Open field, rotarod, Morris water maze and passive avoidance learning was used to evaluate the motor and cognitive function of the animals. ANOVA and repeated measures ANOVA were used to analyze the data. p balance function by BDL was reversed by ERY. Spatial and passive avoidance learning impairments observed in BDL rats were also reversed by chronic administration of ERY. ERY can be offered as a potential neuroprotective agent in the treatment of patients with HC that manifest mental dysfunctions. Though further studies are needed to clarify the exact mechanisms, the neuroprotective properties of ERY against BDL impairments were demonstrated in the current study.

  20. Erythropoietin protects myocardin-expressing cardiac stem cells against cytotoxicity of tumor necrosis factor-{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Madonna, Rosalinda [The Center for Cardiovascular Biology and Atherosclerosis Research, The University of Texas Health Science Center at Houston, Texas (United States); Institute of Cardiology, and Center of Excellence on Aging, ' G. d' Annunzio' University, Chieti (Italy); Shelat, Harnath; Xue, Qun; Willerson, James T. [The Center for Cardiovascular Biology and Atherosclerosis Research, The University of Texas Health Science Center at Houston, Texas (United States); The Texas Heart Institute at St. Luke' s Episcopal Hospital, Houston, Texas (United States); De Caterina, Raffaele [Institute of Cardiology, and Center of Excellence on Aging, ' G. d' Annunzio' University, Chieti (Italy); Geng, Yong-Jian, E-mail: yong-jian.geng@uth.tmc.edu [The Center for Cardiovascular Biology and Atherosclerosis Research, The University of Texas Health Science Center at Houston, Texas (United States); The Texas Heart Institute at St. Luke' s Episcopal Hospital, Houston, Texas (United States)

    2009-10-15

    Cardiac stem cells are vulnerable to inflammation caused by infarction or ischemic injury. The growth factor, erythropoietin (Epo), ameliorates the inflammatory response of the myocardium to ischemic injury. This study was designed to assess the role of Epo in regulation of expression and activation of the cell death-associated intracellular signaling components in cardiac myoblasts stimulated with the proinflammatory cytokine tumor necrosis factor (TNF)-{alpha}. Cardiac myoblasts isolated from canine embryonic hearts characterized by expression of myocardin A, a promyogenic transcription factor for cardiovascular muscle development were pretreated with Epo and then exposed to TNF-{alpha}. Compared to untreated cells, the Epo-treated cardiac myoblasts exhibited better morphology and viability. Immunoblotting revealed lower levels of active caspase-3 and reductions in iNOS expression and NO production in Epo-treated cells. Furthermore, Epo pretreatment reduced nuclear translocation of NF-{kappa}B and inhibited phosphorylation of inhibitor of kappa B (I{kappa}B) in TNF-{alpha}-stimulated cardiac myoblasts. Thus, Epo protects cardiac myocyte progenitors or myoblasts against the cytotoxic effects of TNF-{alpha} by inhibiting NF-{kappa}B-mediated iNOS expression and NO production and by preventing caspase-3 activation.

  1. Dexamethasone mimics aspects of physiological acclimatization to 8 hours of hypoxia but suppresses plasma erythropoietin

    Science.gov (United States)

    Liu, Chun; Croft, Quentin P. P.; Kalidhar, Swati; Brooks, Jerome T.; Herigstad, Mari; Smith, Thomas G.; Dorrington, Keith L.

    2013-01-01

    Dexamethasone ameliorates the severity of acute mountain sickness (AMS) but it is unknown whether it obtunds normal physiological responses to hypoxia. We studied whether dexamethasone enhanced or inhibited the ventilatory, cardiovascular, and pulmonary vascular responses to sustained (8 h) hypoxia. Eight healthy volunteers were studied, each on four separate occasions, permitting four different protocols. These were: dexamethasone (20 mg orally) beginning 2 h before a control period of 8 h of air breathing; dexamethasone with 8 h of isocapnic hypoxia (end-tidal Po2 = 50 Torr); placebo with 8 h of air breathing; and placebo with 8 h of isocapnic hypoxia. Before and after each protocol, the following were determined under both euoxic and hypoxic conditions: ventilation; pulmonary artery pressure (estimated using echocardiography to assess maximum tricuspid pressure difference); heart rate; and cardiac output. Plasma concentrations of erythropoietin (EPO) were also determined. Dexamethasone had no early (2-h) effect on any variable. Both dexamethasone and 8 h of hypoxia increased euoxic values of ventilation, pulmonary artery pressure, and heart rate, together with the ventilatory sensitivity to acute hypoxia. These effects were independent and additive. Eight hours of hypoxia, but not dexamethasone, increased the sensitivity of pulmonary artery pressure to acute hypoxia. Dexamethasone, but not 8 h of hypoxia, increased both cardiac output and systemic arterial pressure. Dexamethasone abolished the rise in EPO induced by 8 h of hypoxia. In summary, dexamethasone enhances ventilatory acclimatization to hypoxia. Thus, dexamethasone in AMS may improve oxygenation and thereby indirectly lower pulmonary artery pressure. PMID:23393065

  2. Effects of erythropoietin on memory-relevant neurocircuitry activity and recall in mood disorders.

    Science.gov (United States)

    Miskowiak, K W; Macoveanu, J; Vinberg, M; Assentoft, E; Randers, L; Harmer, C J; Ehrenreich, H; Paulson, O B; Knudsen, G M; Siebner, H R; Kessing, L V

    2016-09-01

    Erythropoietin (EPO) improves verbal memory and reverses subfield hippocampal volume loss across depression and bipolar disorder (BD). This study aimed to investigate with functional magnetic resonance imaging (fMRI) whether these effects were accompanied by functional changes in memory-relevant neuro-circuits in this cohort. Eighty-four patients with treatment-resistant unipolar depression who were moderately depressed or BD in remission were randomized to eight weekly EPO (40 000 IU) or saline infusions in a double-blind, parallel-group design. Participants underwent whole-brain fMRI at 3T, mood ratings, and blood tests at baseline and week 14. During fMRI, participants performed a picture encoding task followed by postscan recall. Sixty-two patients had complete data (EPO: N = 32, saline: N = 30). EPO improved picture recall and increased encoding-related activity in dorsolateral prefrontal cortex (dlPFC) and temporo-parietal regions, but not in hippocampus. Recall correlated with activity in the identified dlPFC and temporo-parietal regions at baseline, and change in recall correlated with activity change in these regions from baseline to follow-up across the entire cohort. The effects of EPO were not correlated with change in mood, red blood cells, blood pressure, or medication. The findings highlight enhanced encoding-related dlPFC and temporo-parietal activity as key neuronal underpinnings of EPO-associated memory improvement. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Erythropoietin: a candidate treatment for mood symptoms and memory dysfunction in depression.

    Science.gov (United States)

    Miskowiak, Kamilla W; Vinberg, Maj; Harmer, Catherine J; Ehrenreich, Hannelore; Kessing, Lars V

    2012-02-01

    Current pharmacological treatments for depression have a significant treatment-onset-response delay, an insufficient efficacy for many patients and fail to reverse cognitive dysfunction. Erythropoietin (EPO) has neuroprotective and neurotrophic actions and improves cognitive function in animal models of acute and chronic neurodegenerative conditions and in patients with cognitive decline. We systematically reviewed the published findings from animal and human studies exploring the potential of EPO to treat depression-related cognitive dysfunction and depression. We identified five animal studies (two in male rats, two in male mice and one in male rats and mice) and seven human proof-of-concept studies (five in healthy volunteers and two in depressed patients) that investigated the above. All of the reviewed animal studies but one and all human studies demonstrated beneficial effects of EPO on hippocampus-dependent memory and antidepressant-like effects. These effects appear to be mediated through direct neurobiological actions of EPO rather than upregulation of red cell mass. The reviewed studies demonstrate beneficial effects of EPO on hippocampus-dependent memory function and on depression-relevant behavior, thus highlighting EPO as a candidate agent for future management of cognitive dysfunction and mood symptoms in depression. Larger-scale clinical trials of EPO as a treatment for mood and neurocognitive symptoms in patients with mood disorder are therefore warranted.

  4. Erythropoietin as an adjunctive treatment for methanol-induced toxic optic neuropathy.

    Science.gov (United States)

    Pakravan, Mohammad; Esfandiari, Hamed; Sanjari, Nasrin; Ghahari, Elham

    2016-11-01

    Methanol-induced optic neuropathy (MTON) is frequently seen in countries where alcohol consumption is banned or poorly regulated. MTON frequently results in blindness and there is no empirically validated treatment. To evaluate the effect of erythropoietin (EPO) as an adjunctive treatment for MTON. In this nonrandomized interventional comparative study, all participants were diagnosed with MTON and received the steroid methylprednisolone. Eleven participants received intravenous EPO (10000 IU twice a day) for three days as an adjuvant to methylprednisolone (EPO group); 11 participants in a historical control group received methylprednisolone only (control group). Main outcomes were best-corrected visual acuity (BCVA), peripapillary retinal nerve fiber layer thickness (PRNFLT), and visual field mean deviation (MD). Mean BCVA improved significantly in both groups: from 2.93 ± 0.55 to 1.75 ± 1.16 LogMAR at month 3 (p < 0.001) in the EPO group, and from 2.65 ± 0.68 to 2.19 ± 0.75 at final visit in the control group (p = 0.001). The final BCVA was significantly better in the EPO group (p = 0.012). The mean PRNFLT decreased in both groups. However, at the final follow-up, PRNFLT was significantly thinner in the control group (53 ± 6 vs. 77 ± 26 microns, respectively; p < 0.001). Intravenous EPO plus high-dose intravenous steroid may be an effective combination therapy for the patients with MTON.

  5. Inhibition of erythropoietin siRNA on corneal neovascularization of rabbit

    Directory of Open Access Journals (Sweden)

    Yu-Shun Xue

    2017-03-01

    Full Text Available AIM: To observe the expression of erythropoietin(EPOon the corneal of rabbit and evaluate the inhibition effect of EPO siRNA on corneal neovascularization(CNV. METHODS: Totally 22 healthy rabbits were randomly divided into 2 groups, which were experimental group and normal control group. Both eyes of rabbits in experimental group were chosen to establish corneal neovascularization model by alkali burn. The morphologic change of corneal was observed with slit lamp microscope and the area of CNV was calculated every day. After alkali burn, the right eye of the experimental group was accepted EPO siRNA injection under the conjunctiva, and the left eye was assigned to be experimental control group. The corneal with CNV was collected for immunohistochemistry at 3d, 7d, 14d, 21d after alkali burn, and the expression of EPO was measured. RESULTS: CNV began growing at the 3d after alkali burn in experimental group, and it was vigorous growing at 7d-14d period. The result of immunohistochemistry shows that the expression of EPO increased after the operation. Compared with experimental group, the rabbits who were treated by EPO siRNA was found with less neovascularization on their corneal, and the expression of EPO decreased. There were statistical significance between the two group at different time(PCONCLUSION: EPO is likely to play an important role on CNV growth, and EPO siRNA can inhibit the growth of CNV by restraining the expression of EPO.

  6. High-Dose Erythropoietin and Hypothermia for Hypoxic-Ischemic Encephalopathy: A Phase II Trial.

    Science.gov (United States)

    Wu, Yvonne W; Mathur, Amit M; Chang, Taeun; McKinstry, Robert C; Mulkey, Sarah B; Mayock, Dennis E; Van Meurs, Krisa P; Rogers, Elizabeth E; Gonzalez, Fernando F; Comstock, Bryan A; Juul, Sandra E; Msall, Michael E; Bonifacio, Sonia L; Glass, Hannah C; Massaro, An N; Dong, Lawrence; Tan, Katherine W; Heagerty, Patrick J; Ballard, Roberta A

    2016-06-01

    To determine if multiple doses of erythropoietin (Epo) administered with hypothermia improve neuroradiographic and short-term outcomes of newborns with hypoxic-ischemic encephalopathy. In a phase II double-blinded, placebo-controlled trial, we randomized newborns to receive Epo (1000 U/kg intravenously; n = 24) or placebo (n = 26) at 1, 2, 3, 5, and 7 days of age. All infants had moderate/severe encephalopathy; perinatal depression (10 minute Apgar score in Epo-treated infants (median, 2 vs 11, P = .01). Moderate/severe brain injury (4% vs 44%, P = .002), subcortical (30% vs 68%, P = .02), and cerebellar injury (0% vs 20%, P = .05) were less frequent in the Epo than placebo group. At mean age 12.7 months (SD, 0.9), motor performance in Epo-treated (n = 21) versus placebo-treated (n = 20) infants were as follows: Alberta Infant Motor Scale (53.2 vs 42.8, P = .03); Warner Initial Developmental Evaluation (28.6 vs 23.8, P = .05). High doses of Epo given with hypothermia for hypoxic-ischemic encephalopathy may result in less MRI brain injury and improved 1-year motor function. Copyright © 2016 by the American Academy of Pediatrics.

  7. Erythropoietin preserves the integrity and quality of organs for transplantation after cardiac death.

    Science.gov (United States)

    Maio, Rui; Sepodes, Bruno; Patel, Nimesh S A; Thiemermann, Christoph; Mota-Filipe, Helder; Costa, Paulo

    2011-02-01

    Previous studies have shown that treatment with erythropoietin (EPO) exerts important cytoprotective and antiapoptotic effects. Donor organs recovered after cardiac death (DCD) can alleviate the shortage of organs required for transplantation. However, organs obtained subsequent to cardiac death demonstrate an increased incidence of delayed graft function and primary nonfunction. The aim of this study was to determine the effects of EPO administration to the donor in a porcine model of kidney transplantation under DCD conditions. Landrace pigs received 1,000 IU/kg i.v. EPO 30 min before cardiac arrest. Kidneys were then subjected to 30 min of warm ischemia and were transplanted after 24 h of cold storage. Renal dysfunction, injury, and inflammation were evaluated 4 h after transplantation. Transplantation of kidneys from DCD resulted in significant renal dysfunction, injury, and inflammation. This study provides the first evidence that pretreatment of the donor with a single pharmacologically relevant dose of EPO causes substantial attenuation of the dysfunction and injury associated with the transplantation of kidneys recovered after cardiac death.

  8. Early erythropoietin therapy attenuates remodeling and preserves function of left ventricle in porcine myocardial infarction.

    Science.gov (United States)

    Chua, Sarah; Leu, Steve; Lin, Yu-Chun; Sheu, Jiunn-Jye; Sun, Cheuk-Kwan; Chung, Sheng-Ying; Chai, Han-Tan; Lee, Fan-Yen; Kao, Ying-Hsien; Wu, Chiung-Jen; Chang, Li-Teh; Ko, Sheung-Fat; Yip, Hon-Kan

    2011-03-01

    Erythropoietin (EPO) has been shown to have anti-inflammatory, antiapoptotic, and proangiogenic effects. This study investigated whether early EPO treatment effectively preserves left ventricular (LV) function in porcine acute myocardial infarction (AMI). Eighteen male mini-pigs divided into groups 1 (sham), 2 (AMI), and 3 (AMI with 2 consecutive EPO doses [7500 IU per animal each time] at 30 minutes and 24 hours after AMI induction) underwent echocardiography before and 14 days after AMI induction through left anterior descending artery (LAD) ligation with myocardium harvested for analysis. Larger infarcted areas (IA) were noted in group 2 than in group 3. In both IA and peri-IA, percentage of apoptotic nuclei and CD40-positive cells, messenger RNA expressions of IL-8, matrix metalloproteinase-9, caspase-3, and Bcl-2 associated x protein were highest, whereas proliferator-activated receptor-γ coactivator-1α, endothelial nitric oxide synthase and Bcl-2 were lowest in group 2. Oxidative stress and cytosolic cytochrome c in IA were increased (P porcine AMI model effectively limits infarct size, attenuates LV remodeling, and preserves LV function.

  9. Anti-VEGF therapy in symptomatic peripheral exudative hemorrhagic chorioretinopathy (PEHCR) involving the macula.

    Science.gov (United States)

    Seibel, Ira; Hager, Annette; Duncker, Tobias; Riechardt, Aline I; Nürnberg, Daniela; Klein, Julian P; Rehak, Matus; Joussen, Antonia M

    2016-04-01

    The purpose of this study was to describe the anatomical and functional outcome of vascular endothelial growth factor inhibitor (anti-VEGF) treatment in symptomatic peripheral exudative hemorrhagic chorioretinopathy (PEHCR) involving the macula. Clinical records from patients seen between 2012 and 2013 at a single academic center were reviewed to identify PEHCR patients receiving anti-VEGF therapy due to disease-associated changes involving the macula. Affected eyes were either treated with consecutive intravitreal injections of anti-VEGF or vitrectomy combined with anti-VEGF followed by pro re nata injections. The mean age of the patients was 76 years (range 70-89 years). In all nine eyes, visual acuity was reduced due to central subretinal fluid. On average, three anti-VEGF injections (range 2-5 injections) were required initially to achieve complete resolution of macular subretinal fluid. In three eyes, subretinal fluid reappeared after an average of 10 months (range 5-16 months), and an average of 2.5 anti-VEGF injections (range 2-3 injections) were necessary to attain complete resolution of macular subretinal fluid a second time. Median visual acuity at the visit before the first injection was 1.0 logMAR (range 2.1-0.4 logMAR) and increased to 0.8 logMAR (range 2-0.1 logMAR) at the last visit. Results of this study show that for cases in which PEHCR becomes symptomatic due to macular involvement, anti-VEGF treatment may have drying potential. Although vision was improved in some patients, it remained limited in cases with long-term macular involvement, precluding any definitive functional conclusion. However, we believe that the use of anti-VEGF agents should be recommended in PEHCR that threatens the macula. Due to its often self-limiting course, peripheral lesions should be closely observed. Larger studies are needed in order to provide clear evidence of the efficacy of anti-VEGF therapy in PEHCR.

  10. The tetrapeptide Arg-Leu-Tyr-Glu inhibits VEGF-induced angiogenesis

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    Baek, Yi-Yong; Lee, Dong-Keon [Department of Molecular and Cellular Biochemistry, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-702 (Korea, Republic of); So, Ju-Hoon; Kim, Cheol-Hee [Department of Biology, Chungnam National University, Daejeon, 305-764 (Korea, Republic of); Jeoung, Dooil [Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, Gangwon-do, 200-702 (Korea, Republic of); Lee, Hansoo [Department of Life Sciences, College of Natural Sciences, Kangwon National University, Chuncheon, Gangwon-do, 200-702 (Korea, Republic of); Choe, Jongseon [Department of Immunology, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-702 (Korea, Republic of); Won, Moo-Ho [Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-702 (Korea, Republic of); Ha, Kwon-Soo [Department of Molecular and Cellular Biochemistry, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-702 (Korea, Republic of); Kwon, Young-Guen [Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-752 (Korea, Republic of); Kim, Young-Myeong, E-mail: ymkim@kangwon.ac.kr [Department of Molecular and Cellular Biochemistry, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, 200-702 (Korea, Republic of)

    2015-08-07

    Kringle 5, derived from plasminogen, is highly capable of inhibiting angiogenesis. Here, we have designed and synthesized 10 tetrapeptides, based on the amino acid properties of the core tetrapeptide Lys-Leu-Tyr-Asp (KLYD) originating from anti-angiogenic kringle 5 of human plasminogen. Of these, Arg-Leu-Tyr-Glu (RLYE) effectively inhibited vascular endothelial growth factor (VEGF)-induced endothelial cell proliferation, migration and tube formation, with an IC{sub 50} of 0.06–0.08 nM, which was about ten-fold lower than that of the control peptide KLYD (0.79 nM), as well as suppressed developmental angiogenesis in a zebrafish model. Furthermore, this peptide effectively inhibited the cellular events that precede angiogenesis, such as ERK and eNOS phosphorylation and nitric oxide production, in endothelial cells stimulated with VEGF. Collectively, these data demonstrate that RLYE is a potent anti-angiogenic peptide that targets the VEGF signaling pathway. - Highlights: • The tetrapeptide RLYE inhibited VEGF-induced angiogenesis in vitro. • RLYE also suppressed neovascularization in a zebrafish model. • Its effect was correlated with inhibition of VEGF-induced ERK and eNOS activation. • RLYE may be used as a therapeutic drug for angiogenesis-related diseases.

  11. Effects of Shuangdanmingmu capsule on retinal vascular morphology and VEGF expression in rats with diabetic retinopathy

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    Yu-Hui Qin

    2015-01-01

    Full Text Available AIM: To observe the effects of Shuangdanmingmu capsule on VEGF expression and retinal vascular morphology in rats with diabetic retinopathy(DR. METHODS: DR rats were fed with Shuangdanmingmu capsule. By comparing with the normal group, the model control group, and positive control group, the effect of Shuangdanmingmu capsule on retinal tissue of DR rats was observed under electron microscopy. After HE staining, retinal structure was observed under the light microscope. Immunohitochemical staining was used to detect the VEGF expression in retina.RESULTS:Two months after treatment, the layers tissue of retina presented mild edema, capillary pericytes performed edema, mitochondria showed mild swelling and less clear structure, some endothelial cells showed slight proliferation in Shuangdanmingmu group. Compared with the normal group, the expression level of VEGF in retina increased in the other groups, especially in model control group. A significant differential in expression of VEGF was found between Shuangdanmingmu group, positive control group and model control group(PCONCLUSION: Shuangdanmingmu capsule can effectively improve the retinal microvascular, reduce edema and necrosis of each layer of retina, improve the ultrastructure of retina's tissue and inhibit VEGF expression in DR rats.

  12. Reducing VEGF-B Signaling Ameliorates Renal Lipotoxicity and Protects against Diabetic Kidney Disease.

    Science.gov (United States)

    Falkevall, Annelie; Mehlem, Annika; Palombo, Isolde; Heller Sahlgren, Benjamin; Ebarasi, Lwaki; He, Liqun; Ytterberg, A Jimmy; Olauson, Hannes; Axelsson, Jonas; Sundelin, Birgitta; Patrakka, Jaakko; Scotney, Pierre; Nash, Andrew; Eriksson, Ulf

    2017-03-07

    Diabetic kidney disease (DKD) is the most common cause of severe renal disease, and few treatment options are available today that prevent the progressive loss of renal function. DKD is characterized by altered glomerular filtration and proteinuria. A common observation in DKD is the presence of renal steatosis, but the mechanism(s) underlying this observation and to what extent they contribute to disease progression are unknown. Vascular endothelial growth factor B (VEGF-B) controls muscle lipid accumulation through regulation of endothelial fatty acid transport. Here, we demonstrate in experimental mouse models of DKD that renal VEGF-B expression correlates with the severity of disease. Inhibiting VEGF-B signaling in DKD mouse models reduces renal lipotoxicity, re-sensitizes podocytes to insulin signaling, inhibits the development of DKD-associated pathologies, and prevents renal dysfunction. Further, we show that elevated VEGF-B levels are found in patients with DKD, suggesting that VEGF-B antagonism represents a novel approach to treat DKD. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. TNF-α-Induced VEGF and MMP-9 Expression Promotes Hemorrhagic Transformation in Pituitary Adenomas

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    Qin Liu

    2011-06-01

    Full Text Available Pituitary apoplexy is a clinical syndrome with unknown pathogenesis. Therefore, identifying the underlying mechanisms is of high clinical relevance. Tumor necrosis factor alpha (TNF-α is a critical cytokine mediating various hemorrhagic events, but little is known about its involvement in pituitary apoplexy. Here we show that TNF-α may be an important regulator of hemorrhagic transformation in pituitary adenomas. In this study, sixty surgical specimens of hemorrhagic and non-hemorrhagic human pituitary adenomas were examined. Hemorrhagic pituitary adenomas displayed higher protein and mRNA levels of TNF-α, vascular endothelial growth factor (VEGF and matrix metalloproteinase-9 (MMP-9 compared with those of non-hemorrhagic tumors. Exposure of MMQ pituitary adenoma cells to TNF-α induced VEGF and MMP-9 expression in vitro. Additionally, TNF-α administration caused hemorrhagic transformation and enhanced VEGF and MMP-9 expression in MMQ pituitary adenoma cell xenografts in mice. Blockers of VEGF or MMP-9, either alone or in combination, attenuated but not abrogated TNF-α mediated hemorrhagic transformation in xenografts. This study suggests that TNF-α may play a role in the development of intratumoral hemorrhage in pituitary adenomas via up-regulation of VEGF and MMP-9.

  14. Prediction of Anti-VEGF Response in Diabetic Macular Edema After 1 Injection.

    Science.gov (United States)

    Shah, Ankoor R; Yonekawa, Yoshihiro; Todorich, Bozho; Van Laere, Lily; Hussain, Rehan; Woodward, Maria A; Abbey, Ashkan M; Wolfe, Jeremy D

    2017-05-01

    With multiple anti-vascular endothelial growth factor and steroid therapies available for diabetic macular edema (DME), there is a need for early determination of the best treatment for a particular patient to prevent irreversible vision loss from chronic DME. In this study, we classify patients as responders or non-responders to anti-vascular endothelial growth factor (VEGF) monotherapy in the treatment of DME after a single anti-VEGF injection. The study was designed as a single center, retrospective, interventional case series. We included patients who received 3 consecutive monthly injections with the same anti-VEGF agent. We excluded patients who were treated for DME in the preceding 3 months with any form of anti-VEGF therapy. Visual acuity and central retinal thickness (CRT) data were followed for one year. Receiver operating characteristic (ROC) curve analysis was performed in order to identify cutoff values for identifying responders. 107 eyes were reviewed, with 40 eyes of 34 patients meeting all inclusion criteria. Based on ROC curve analysis, a reduction in CRT by > 15% at 1-month, identified eyes that responded to treatment and had a >25% reduction in CRT at 3-months (sensitivity 0.75, specificity 0.92). DME eyes that have early response to anti-VEGF treatment by reduction in CRT will have significant response to treatment by 3 months.

  15. Effects of finasteride on microvascular density and VEGF expression in glomeruli of diabetic mice

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    He-lin TIAN

    2013-01-01

    Full Text Available Objective  To investigate the effects of finasteride on microvascular density and vascular endothelial growth factor (VEGF expression in glomeruli of streptozotocin-induced diabetic mice. Methods  Diabetes was induced in mice with a single intraperitoneal injection of streptozotocin in a dose of 150mg/kg, and they were randomly divided into 4 groups (7 each: diabetic model group and 3 treatment groups (treated with 0.1, 1, 10mg/kg of finasteride, respectively. Seven normal mice served as control group. Animals in finasteride treatment groups were intragastrically administered with finasteride 0.1, 1 and 10mg/kg once daily for 4 weeks, respectively, and those in control and diabetic model group were given the same volume of normal saline at the same time. The kidney sections from all mice were stained with hematoxylin and eosin (HE for the pathological study, and immunohistochemistry methods were performed to detect the microvascular density, and VEGF expression in glomeruli. Results  Compared with control group, the glomerular area and volume, microvascular density and VEGF index were significantly increased in diabetic model and finasteride treated groups (P<0.05. However, the glomerular area and volume, microvessel density and VEGF index were significantly decreased in 10mg/kg finasteride treated group compared with that in diabetic model group (P<0.05. Conclusion  Finasteride can inhibit the VEGF expression and decrease the glomerular microvascular density in diabetic mice.

  16. Expression of VEGF and semaphorin genes define subgroups of triple negative breast cancer.

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    R Joseph Bender

    Full Text Available Triple negative breast cancers (TNBC are difficult to treat due to a lack of targets and heterogeneity. Inhibition of angiogenesis is a promising therapeutic strategy, but has had limited effectiveness so far in breast cancer. To quantify heterogeneity in angiogenesis-related gene expression in breast cancer, we focused on two families--VEGFs and semaphorins--that compete for neuropilin co-receptors on endothelial cells. We compiled microarray data for over 2,600 patient tumor samples and analyzed the expression of VEGF- and semaphorin-related ligands and receptors. We used principal component analysis to identify patterns of gene expression, and clustering to group samples according to these patterns. We used available survival data to determine whether these clusters had prognostic as well as therapeutic relevance. TNBC was highly associated with dysregulation of VEGF- and semaphorin-related genes; in particular, it appeared that expression of both VEGF and semaphorin genes were altered in a pro-angiogenesis direction. A pattern of high VEGFA expression with low expression of secreted semaphorins was associated with 60% of triple-negative breast tumors. While all TNBC groups demonstrated poor prognosis, this signature also correlated with lower 5-year survival rates in non-TNBC samples. A second TNBC pattern, including high VEGFC expression, was also identified. These pro-angiogenesis signatures may identify cancers that are more susceptible to VEGF inhibition.

  17. Quantification of plasma and bone marrow VEGF and angiopoietin-2 levels in pediatric malignancies.

    Science.gov (United States)

    Hintsala, Emilia; Bono, Petri; Andersson, Sture; Kivivuori, Sanna-Maria

    2012-10-01

    Data on angiogenesis in pediatric patients with malignancy are scarce. Our aim was to study angiogenic growth factors vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang2) in pediatric oncological patients at diagnosis and a few months after the beginning of the therapy. Eighty-four consecutive patients with malignancy were included in this study. The levels of plasma and bone marrow VEGF and Ang2 were analyzed by enzyme-linked immunosorbent assay. The levels of VEGF were higher in patients with solid tumors than in patients with leukemias (P=0.003), whereas Ang2 concentrations showed the opposite (P=0.003). Interestingly, the plasma concentrations of both VEGF and Ang2 correlated with concentrations in the bone marrow (Ppatients with lower VEGF level and patients with higher Ang2 level at follow-up had longer event-free survival than other patients (P=0.032 and 0.053, respectively). The results of our study enlighten the behavior of 2 different angiogenic factors in pediatric patients with malignancy. An interesting finding was the connection between survival of pediatric leukemia patients and angiogenic factor levels a few months after the beginning of therapy. Pathophysiology and clinical applications of these findings need further studies.

  18. Calotropis procera root extracts block VEGF-induced angiogenesis: quantitative analysis.

    Science.gov (United States)

    Mathur, Rajani; Gupta, Suresh Kumar; Mathur, Sandeep Rajinder; Velpandian, Thirumurthy

    2011-01-01

    Angiogenesis is controlled by number of growth factors, including vascular endothelial growth factor (VEGF). Plant derived anti-angiogenic molecules acting via VEGF are being investigated for curtailing angiogenesis dependent diseases. In this study, methanolic (CM), n-hexane (CH), ethylacetate (CE) and water (CW) extracts of the roots of Calotropis procera were tested for anti-angiogenic activity. In the chicken egg chorioallantoic membrane (CAM) assay, CM, CH and CE but not CW inhibited VEGF-induced neovascularization in a dose-dependent manner. Of all the tested extracts, CM at the dose of 10, 5 and 2.5 ng most effectively inhibited over 83, 71 and 64%, of neovascularization induced by 10ng of VEGF, respectively. Sponge implantation assay in mice further showed that at the dose of 100ng CM, CH and CE but not CW significantly inhibited neovascularization induced by VEGF (100 ng). Taken together, this study indicates that the root extracts of C. procera may possess anti-angiogenic activity.

  19. DC electric stimulation upregulates angiogenic factors in endothelial cells through activation of VEGF receptors.

    Science.gov (United States)

    Bai, Huai; Forrester, John V; Zhao, Min

    2011-07-01

    Small direct current (DC) electric fields direct some important angiogenic responses of vascular endothelial cells. Those responses indicate promising use of electric fields to modulate angiogenesis. We sought to determine the regulation of electric fields on transcription and expression of a serial of import angiogenic factors by endothelial cells themselves. Using semi-quantitative PCR and ELISA we found that electric stimulation upregulates the levels of mRNAs and proteins of a number of angiogenic proteins, most importantly VEGF165, VEGF121 and IL-8 in human endothelial cells. The up-regulation of mRNA levels might be specific, as the mRNA encoding bFGF, TGF-beta and eNOS are not affected by DC electric stimulation at 24h time-point. Inhibition of VEGF receptor (VEGFR1 or VEGFR2) signaling significantly decreased VEGF production and completely abolished IL-8 production. DC electric stimulation selectively regulates production of some growth factors and cytokines important for angiogenesis through a feed-back loop mediated by VEGF receptors. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. PEDF and VEGF-A output from human retinal pigment epithelial cells grown on novel microcarriers.

    Science.gov (United States)

    Falk, Torsten; Congrove, Nicole R; Zhang, Shiling; McCourt, Alexander D; Sherman, Scott J; McKay, Brian S

    2012-01-01

    Human retinal pigment epithelial (hRPE) cells have been tested as a cell-based therapy for Parkinson's disease but will require additional study before further clinical trials can be planned. We now show that the long-term survival and neurotrophic potential of hRPE cells can be enhanced by the use of FDA-approved plastic-based microcarriers compared to a gelatin-based microcarrier as used in failed clinical trials. The hRPE cells grown on these plastic-based microcarriers display several important characteristics of hRPE found in vivo: (1) characteristic morphological features, (2) accumulation of melanin pigment, and (3) high levels of production of the neurotrophic factors pigment epithelium-derived factor (PEDF) and vascular endothelial growth factor-A (VEGF-A). Growth of hRPE cells on plastic-based microcarriers led to sustained levels (>1 ng/ml) of PEDF and VEGF-A in conditioned media for two months. We also show that the expression of VEGF-A and PEDF is reciprocally regulated by activation of the GPR143 pathway. GPR143 is activated by L-DOPA (1 μM) which decreased VEGF-A secretion as opposed to the previously reported increase in PEDF secretion. The hRPE microcarriers are therefore novel candidate delivery systems for achieving long-term delivery of the neuroprotective factors PEDF and VEGF-A, which could have a value in neurodegenerative conditions such as Parkinson's disease.

  1. Low Molecular Weight Fucoidan Inhibits Tumor Angiogenesis through Downregulation of HIF-1/VEGF Signaling under Hypoxia

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    Meng-Chuan Chen

    2015-07-01

    Full Text Available Activation of hypoxia-induced hypoxia-inducible factors-1 (HIF-1 plays a critical role in promoting tumor angiogenesis, growth and metastasis. Low molecular weight fucoidan (LMWF is prepared from brown algae, and exhibits anticancer activity. However, whether LMWF attenuates hypoxia-induced angiogenesis in bladder cancer cells and the molecular mechanisms involved remain unclear. This is the first study to demonstrate that LMWF can inhibit hypoxia-stimulated H2O2 formation, HIF-1 accumulation and transcriptional activity vascular endothelial growth factor (VEGF secretion, and the migration and invasion in hypoxic human bladder cancer cells (T24 cells. LMWF also downregulated hypoxia-activated phosphorylation of PI3K/AKT/mTOR/p70S6K/4EBP-1 signaling in T24 cells. Blocking PI3K/AKT or mTOR activity strongly diminished hypoxia-induced HIF-1α expression and VEGF secretion in T24 cells, supporting the involvement of PI3K/AKT/mTOR in the induction of HIF-1α and VEGF. Additionally, LMWF significantly attenuated angiogenesis in vitro and in vivo evidenced by reduction of tube formation of hypoxic human umbilical vascular endothelial cells and blood capillary generation in the tumor. Similarly, administration of LMWF also inhibited the HIF-1α and VEGF expression in vivo, accompanied by a reduction of tumor growth. In summary, under hypoxia conditions, the antiangiogenic activity of LMWF in bladder cancer may be associated with suppressing HIF-1/VEGF-regulated signaling pathway.

  2. The role of VEGF and KDR polymorphisms in moyamoya disease and collateral revascularization.

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    Young Seok Park

    Full Text Available We conducted a case-control study to investigate whether vascular endothelial growth factor (VEGF -2578, -1154, -634, and 936 and kinase insert domain containing receptor (KDR -604, 1192, and 1719 polymorphisms are associated with moyamoya disease. Korean patients with moyamoya disease (n = 107, mean age, 20.9±15.9 years; 66.4% female and 243 healthy control subjects (mean age, 23.0±16.1 years; 56.8% female were included. The subjects were divided into pediatric and adult groups. Among the 64 surgical patients, we evaluated collateral vessel formation after 2 years and divided patients into good (collateral grade A or poor (collateral grade B and C groups. The frequencies and distributions of four VEGF (-2578, -1154, -634, and 936 and KDR (-604, 1192, and 1719 polymorphisms were assessed from patients with moyamoya disease and compared to the control group. No differences were observed in VEGF -2578, -1154, -634, and 936 or KDR -604, 1192, and 1719 polymorphisms between the control group and moyamoya disease group. However, we found the -634CC genotype occurred less frequently in the pediatric moyamoya group (p = 0.040 whereas the KDR -604C/1192A/1719T haplotype increased the risk of pediatric moyamoya (p = 0.024. Patients with the CC genotype of VEGF -634 had better collateral vessel formation after surgery. Our results suggest that the VEGF -634G allele is associated with pediatric moyamoya disease and poor collateral vessel formation.

  3. Expression of VEGF and semaphorin genes define subgroups of triple negative breast cancer.

    Science.gov (United States)

    Bender, R Joseph; Mac Gabhann, Feilim

    2013-01-01

    Triple negative breast cancers (TNBC) are difficult to treat due to a lack of targets and heterogeneity. Inhibition of angiogenesis is a promising therapeutic strategy, but has had limited effectiveness so far in breast cancer. To quantify heterogeneity in angiogenesis-related gene expression in breast cancer, we focused on two families--VEGFs and semaphorins--that compete for neuropilin co-receptors on endothelial cells. We compiled microarray data for over 2,600 patient tumor samples and analyzed the expression of VEGF- and semaphorin-related ligands and receptors. We used principal component analysis to identify patterns of gene expression, and clustering to group samples according to these patterns. We used available survival data to determine whether these clusters had prognostic as well as therapeutic relevance. TNBC was highly associated with dysregulation of VEGF- and semaphorin-related genes; in particular, it appeared that expression of both VEGF and semaphorin genes were altered in a pro-angiogenesis direction. A pattern of high VEGFA expression with low expression of secreted semaphorins was associated with 60% of triple-negative breast tumors. While all TNBC groups demonstrated poor prognosis, this signature also correlated with lower 5-year survival rates in non-TNBC samples. A second TNBC pattern, including high VEGFC expression, was also identified. These pro-angiogenesis signatures may identify cancers that are more susceptible to VEGF inhibition.

  4. Prognostic significance of cellular vascular endothelial growth factor (VEGF expression in the course of chronic myeloid leukaemia

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    Vidović Ana

    2009-01-01

    Full Text Available Introduction. Increased angiogenesis in bone marrow is one of the characteristics of chronic myeloid leukaemia (CML, a clonal myeloproliferative disorder that expresses a chimeric bcr/abl protein. Vascular endothelial growth factor (VEGF is one of the most potent and a specific regulator of angiogenesis which principally targets endothelial cells and regulates several of their functions, including mitogenesis, permeability and migration. The impact of elevated VEGF expression on the course of chronic myeloid leukaemia is unknown. Objective. The aim of this study was the follow-up of VEGF expression during the course of CML. Methods. We studied VEGF expression of 85 CML patients (median age 50 years, range 16-75 years. At the commencement of the study, 29 patients were in chronic phase (CP, 25 in an accelerated phase (AP, and 31 in the blast crisis (BC. The temporal expression (percentage positivity per 1000 analysed cells VEGF proteins over the course of CML were studied using the immunohistochemical technique utilizing relevant monoclonal antibodies. It was correlated with the laboratory (Hb, WBC and platelet counts, and the percentage of blasts and clinical parameters (organomegaly, duration of CP, AP, and BC of disease progression. Results. The expression of VEGF protein was most pronounced in AP (ANOVA, p=0.033. The level of VEGF expression correlated inversely with the degree of splenomegaly (Pearson, r=-0.400, p=0.011. High expression of VEGF correlated with a shorter overall survival (log rank, p=0.042. Conclusion. Immunohistochemically confirmed significance of the expression of VEGF in dependence of the CML stage could be of clinical importance in deciding on the timing therapy. These data suggest that VEGF plays a role in the biology of CML and that VEGF inhibitors should be investigated in CML.

  5. The therapeutic role of VEGF-expressing muscle-derived stem cells in acute penile cavernosal injury.

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    An, Geng; Ji, Chenyang; Wei, Zhe; Chen, Hao; Zhang, Jinming

    2012-08-01

    Traumatic penile injury is one of the urological emergencies. Surgery and conservative management are major treatment methods but are always accompanied by many complications. To investigate the feasibility of repairing cavernous tissues in acute rabbit penile cavernosal injury model with vascular endothelial growth factor (VEGF)-expressing muscle-derived stem cells (MDSCs). MDSCs were isolated and transfected with hVEGF165 lentiviral gene vector in vitro. The expression of VEGF was confirmed using enzyme-linked immunosorbent assay (ELISA), Western blot, and real-time polymerase chain reaction (PCR) analyses. After animal models were constructed, animals were randomly divided into four groups, which were administrated with MDSCs/VEGF, MDSCs/vector, MDSCs, and normal saline, respectively. A month later, magnetic resonance imaging (MRI) and intracavernosal pressures (ICP) were performed on the animals. Then penile tissues were harvested and assayed with Western blot and immunohistochemistry. Real-time PCR, Western blot, ELISA, immunohistochemistry, MRI, and ICP were performed in our experiments. The expression of VEGF significantly increased in the VEGF-expressing MDSCs group compared with those in the MDSCs/vector and MDSCs groups. VEGF protein expression in the injury sites of cavernous tissues were significantly higher in the MDSCs/VEGF group compared with those in other three groups. Immunohistochemical staining showed that α-smooth muscle actin-positive cells, von Willebrand factor-positive cells and capillary density markedly increased in the MDSCs/VEGF group. Animals receiving MDSCs/VEGF showed a significant improvement in cavernosal contractile function and structural repair. The transplantation of VEGF-expressing MDSCs could repair the actuely injured cavernous tissue. We believed that it could be a novel therapeutic strategy for acute rabbit penile cavernosal injury. © 2012 International Society for Sexual Medicine.

  6. Fructose diet and VEGF-induced plasma extravasation in hamster cheek pouch.

    Science.gov (United States)

    Félétou, Michel; Boulanger, Michelle; Staczek, Joanna; Broux, Olivier; Duhault, Jacques

    2003-03-01

    To determine in the hamster cheek pouch whether or not the changes in plasma extravasation induced by vascular endothelial growth factor (VEGF) could be affected by fructose diet. Hamsters were subjected to control drinking water or to water containing fructose (10 %) for 18 weeks. The fructose diet induced a small but significant increase in glycemia (0.80+/-0.11 and 1.09+/-0.15, n=8 and 9 for control and fructose- treated animals, respectively, Pdiet while the effects of VEGF were markedly increased (maximal number of leakage sites: 76+/-20 and 126+/-55, n = 8 and 9 for control and fructose-treated animals, respectively, P<0.01). Even moderate changes in glycemic levels can produce profound alteration in the VEGF response.

  7. Increased serum levels of sortilin are associated with depression and correlated with BDNF and VEGF

    DEFF Research Database (Denmark)

    Buttenschøn, Henriette Nørmølle; Demontis, Ditte; Ollendorff, Mathias Kaas

    2015-01-01

    measured by immunoassay, and potential determinants of the serum sortilin level were assessed by generalized linear models. Serum levels of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) were measured in previous studies. We identified a significant increase of serum...... sortilin levels in depressed individuals compared with controls (P = 0.0002) and significant positive correlation between serum sortilin levels and the corresponding levels of BDNF and VEGF. None of the genotyped SNPs were associated with depression. Additional analyses showed that the serum sortilin level...... was influenced by several other factors. Alcohol intake and body mass index, as well as depression, serum BDNF and serum VEGF were identified as predictors of serum sortilin levels in our final multivariate model. In conclusion, the results suggest a role of circulating sortilin in depression which may relate...

  8. Estimation of Immunohistochemical Expression of VEGF in Ductal Carcinomas of the Breast

    DEFF Research Database (Denmark)

    Maae, Else; Nielsen, Martin; Dahl Steffensen, Karina

    2012-01-01

    . Material and methods: We immunostained whole tumor sections for VEGF-A, -B, and VEGFR-1 of invasive ductal carcinomas of the breast and scored the tumors manually by staining intensity as the only parameter and by a combination of qualitative and quantitative staining information. We also introduced...... an automated method for analyzing VEGF expression (so-called AI score) using the same tumor sections. Analysis of 100% of the tumor area was performed and the results were compared to the reduced analysis of 25% of the tumor area. These analyses were performed at 5x and 10x magnification and each analysis...... was repeated in a second run with a new delineation of the tumor area. Results: We found that the AI scores were correlated to the manual scoring of VEGF intensity, but the reproducibility of manual IHC scores was rather poor. The AI scores were reproducible and the restricted analysis of 25% of the tumor area...

  9. Estimation of Immunohistochemical Expression of VEGF in Ductal Carcinomas of the Breast

    DEFF Research Database (Denmark)

    Maae, Else; Nielsen, Martin; Dahl Steffensen, Karina

    2011-01-01

    whole tumor sections for VEGF-A, -B, and VEGFR-1 of invasive ductal carcinomas of the breast and scored the tumors manually with staining intensity as the only parameter and by a combination of qualitative and quantitative information. We also introduce an automated method for analyzing VEGF expression...... (so-called AI score) using the same tumor sections. Analysis of 100% of the tumor area was performed and the results were compared to the reduced analysis of 25% of the tumor area. These analyses were performed at 5x and 10x magnification and each analysis was repeated in a second run with a new...... delineation of the tumor area. We found that the AI scores were correlated to the manual scoring of VEGF intensity, but reproducibility of manual IHC scores was rather poor. The AI scores were reproducible and the restricted analysis of 25% of the tumor area at 5x magnifications was the most efficient...

  10. Water extract of Cinnamomum cassia suppresses angiogenesis through inhibition of VEGF receptor 2 phosphorylation.

    Science.gov (United States)

    Kim, Eok-Cheon; Kim, Hye Jin; Kim, Tack-Joong

    2015-01-01

    Angiogenesis, the process of new blood vessel formation, has been a major target for cancer therapy. Antiangiogenic herbal medicines are useful in the treatment of cancer. In this study, we found that a water extract of Cinnamomum cassia (CCWE) was a potent inhibitor of angiogenesis. In cultured human umbilical vein endothelial cells, CCWE suppressed vascular endothelial growth factor (VEGF)-induced proliferation, migration, invasion, tube formation, and intracellular signaling events such as phosphorylation of ERK, p38 and VEGFR2, and activation of matrix metalloproteinase. Furthermore, CCWE inhibited VEGF-induced vessel sprouting of rat aorta ex vivo. These findings might be of particular interest for drug development because VEGF signaling is a potential target for treatment of angiogenesis-associated diseases.

  11. A positive circuit of VEGF increases Glut-1 expression by increasing HIF-1α gene expression in human retinal endothelial cells.

    Science.gov (United States)

    Choi, Yoon Kyung

    2017-12-01

    Treatment of human retinal microvascular endothelial cells (HRMECs) with vascular endothelial growth factor 165 (VEGF 165 ) increased hypoxia-inducible factor 1α (HIF-1α), VEGF, and glucose transporter 1 (Glut-1) mRNA expression and Glut-1 protein localization to the membrane. In contrast, treatment of human retinal pigment epithelium cells with VEGF 165 did not induce HIF-1α, VEGF, and Glut-1 gene expression. Microvascular endothelial cells are surrounded by astrocytic end feet in the retina. Astrocyte-derived A-kinase anchor protein 12 overexpression during hypoxia downregulated VEGF secretion, and this conditioned medium reduced VEGF and Glut-1 expression in HRMECs, suggesting that communications between astrocytes and endothelial cells may be the determinants of the blood vessel network. In HRMECs, HIF-1α small interfering RNA transfection blocked the VEGF 165 -mediated increase in VEGF and Glut-1 gene expression. Inhibition of protein kinase C (PKC) with inhibitor GF109203X or with a small interfering RNA targeting PKCζ attenuated the VEGF 165 -induced Glut-1 protein expression and VEGF and Glut-1 mRNA expression. In addition, results of an immunoprecipitation assay imply an interaction between VEGF receptor 2 (VEGFR2) and PKCζ in HRMECs. Therefore, VEGF secretion by hypoxic astrocytes may upregulate HIF-1α gene expression, inducing VEGF and Glut-1 expression via the VEGFR2-PKCζ axis in HRMECs.

  12. Long-term L-Carnitine Administration reduces Erythropoietin Resistance in Chronic Hemodialysis Patients with Thalassemia Minor

    Directory of Open Access Journals (Sweden)

    Biagio R. Di Iorio

    2007-01-01

    Full Text Available Background and Aim: Both thalassemia and carnitine deficiency represent independent causes of erythropoietin resistance, and thus anemia, in uremic patients. We evaluated the unknown long-term effects of L-carnitine administration in β-thalassemic on chronic hemodialysis.Methods: We studied twelve subjects (M = 8; F = 4 affected by β-thalassemia minor (β-thal; HbA2 level = 6.6 ± 0.6% and forty non-thalassemic subjects (M = 24; F = 16 as controls (C, on chronic hemodialysis treatment. Patients and controls were at target hemoglobin levels (11–12g/dl prior to the study and underwent to i.v. L-carnitine administration for a one year period-time.Results: Groups were comparable for age, gender, serum levels of hemoglobin (Hb, iron, ferritine, PTH and aluminum, transferrin saturation, and dialysis modalities. During the study both groups showed signifi cant Hb increase and erythropoietin (EPO decrease; as a difference, such changes emerged at the 3rd month in C but at the 8th month in β-thal. At start, during the dialysis session the erythrocyte MCV reduced in C but not in β-thal (65.3 ± 3.2 to 65.5 ± 3.2 fl ; NS; along carnitine administration period, however, MCV during dialysis decreased also in β-thal, starting since the 9th month of treatment.Conclusion: This study provides evidence of the lowering of EPO resistance in β-thalassemia patients on hemodialysis due to long-term carnitine administration. Thus, prolonged carnitine supplementation should be suggested to patients on dialysis affected by β-thalassemia with poorly responsive anemia, or requiring large doses of erythropoietin.

  13. Long-term L-Carnitine Administration reduces Erythropoietin Resistance in Chronic Hemodialysis Patients with Thalassemia Minor

    Directory of Open Access Journals (Sweden)

    Biagio R. Di Iorio

    2007-01-01

    Full Text Available Background and Aim Both thalassemia and carnitine deficiency represent independent causes of erythropoietin resistance, and thus anemia, in uremic patients. We evaluated the unknown long-term effects of L-carnitine administration in β-thalassemic on chronic hemodialysis. Methods We studied twelve subjects (M = 8; F = 4 affected by β-thalassemia minor (β-thal; HbA2 level = 6.6 ± 0.6% and forty non-thalassemic subjects (M = 24; F = 16 as controls (C, on chronic hemodialysis treatment. Patients and controls were at target hemoglobin levels (11–12g/dl prior to the study and underwent to i.v. L-carnitine administration for a one year period-time. Results Groups were comparable for age, gender, serum levels of hemoglobin (Hb, iron, ferritine, PTH and aluminum, transferrin saturation, and dialysis modalities. During the study both groups showed significant Hb increase and erythropoietin (EPO decrease; as a difference, such changes emerged at the 3rd month in C but at the 8th month in β-thal. At start, during the dialysis session the erythrocyte MCV reduced in C but not in β-thal (65.3 ± 3.2 to 65.5 ± 3.2 fl; NS; along carnitine administration period, however, MCV during dialysis decreased also in β-thal, starting since the 9th month of treatment. Conclusion This study provides evidence of the lowering of EPO resistance in β-thalassemia patients on hemodialysis due to long-term carnitine administration. Thus, prolonged carnitine supplementation should be suggested to patients on dialysis affected by β-thalassemia with poorly responsive anemia, or requiring large doses of erythropoietin.

  14. Effect of relative hypoparathyroidism on the responsiveness to recombinant human erythropoietin in chronic hemodialysis patients: A single Saudi center experience

    Directory of Open Access Journals (Sweden)

    Khalid Al Saran

    2013-01-01

    Full Text Available Anemia is a common concomitant disorder in dialysis patients. The responsiveness to recombinant human erythropoietin in hemodialysis (HD patients with relative hypoparathyroidism [4 ≤ intact parathyroid hormone (iPTH ≤16.5 pmol/L] remains undetermined. We retrospectively studied 70 chronic hemodialysis patients who were divided into two groups: Group A (32 patients had 16.5 ≤ iPTH levels <33.5 pmol/L and Group B (38 patients had 4 ≥ iPTH≤16.5 pmol/L during the preceding six months without 1- (OH Vitamin D3 administration. The percentage of female gender was significantly higher in Group B compared with Group A (P = 0.018. In Groups A and B, the mean weekly recombinant human erythropoietin dose (U/kg/ week was 227.96 ± 95.24 vs. 154.1 ± 84.9 (P = 0.001 and the mean hemoglobin level was 11.15 ± 0.63 g/dL versus 11.62 ± 0.63 g/dL (P = 0.008. There was no significant statistical difference regarding the other biochemical markers (serum ferritin, iron saturation, serum Ca, serum alkaline phosphatase, C-reactive protein, serum B12, serum folate levels, residual renal function and Kt/v between the groups. If other factors related to anemia are excluded in chronic HD patients, the lower the iPTH level (relative hypoparathyroidism the better the responsiveness to recombinant human erythropoietin.

  15. The response of VEGF-stimulated endothelial cells to angiostatic molecules is substrate-dependent

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    Polverini Peter J

    2005-10-01

    Full Text Available Abstract Background The microenvironment surrounding cells can exert multiple effects on their biological responses. In particular the extracellular matrix surrounding cells can profoundly influence their behavior. It has been shown that the extracellular matrix composition in tumors is vastly different than that found in normal tissue with increased amounts of certain matrices such as collagen I. It has been previously demonstrated that VEGF stimulation of endothelial cells growing on type I collagen results in the induction of bcl-2 expression and enhanced endothelial cell survival. We sought to investigate whether this increased endothelial cell survival resulted in the failure of angiostatic molecules to inhibit angiogenesis. Results We now demonstrate that VEGF-induced survival on collagen I impairs the ability of three known angiostatic molecules, TSP-1, IP-10 and endostatin to inhibit endothelial cell proliferation. Apoptosis of endothelial cells, growing on collagen I, induced by TSP-1 and IP-10 was also inhibited following VEGF stimulation. In contrast, endostatin induced apoptosis in these same cells. Further analysis determined that endostatin did not decrease the expression of bcl-2 nor did it increase activation of caspase-3 in the presence of VEGF. Alternatively, it appeared that in the presence of VEGF, endostatin induced the activation of caspase-8 in endothelial cells grown on collagen I. Furthermore, only endostatin had the ability to inhibit VEGF-induced sprout formation in collagen I gels. Conclusion These data suggest that TSP-1, IP-10 and endostatin inhibit endothelial cells via different mechanisms and that only endostatin is effective in inhibiting angiogenic activities in the presence of collagen I. Our results suggest that the efficacy of angiostatic treatments may be impaired depending on the context of the extracellular matrix within the tumor environment and thus could impede the efficacy of angiostatic therapies.

  16. PDGF-BB/KLF4/VEGF Signaling Axis in Pulmonary Artery Endothelial Cell Angiogenesis.

    Science.gov (United States)

    Liang, Songhe; Yu, Hao; Chen, Xinxin; Shen, Tingting; Cui, Zhongqi; Si, Genle; Zhang, JunTing; Cheng, Yue; Jia, Shiwei; Song, Shasha; Zhang, Xiang; Yu, Xiufeng

    2017-01-01

    Accumulating evidence suggests that platelet-derived growth factor-BB (PDGF-BB) and vascular endothelial growth factor(VEGF) play a role in the progression of pulmonary arterial hypertension (PAH).Since chronic hypoxia is responsible for intimal hyperplasia and disordered angiogenesis of pulmonary arteries, which are histological hallmarks of PAH, we explored the role of the PDGF-BB/KLF4/VEGF signaling axis in the angiogenesis of pulmonary artery endothelial cells (PAECs). Adult male Wistar rats were used to study hypoxia-induced or monocrotaline (MCT)-induced right ventricular (RV) remodeling as well as systolic function and hemodynamics using echocardiography and a pressure-volume admittance catheter. Morphometric analyses of lung vasculature and RV vessels were performed. The results revealed that both the PDGF receptor-tyrosine kinase inhibitor imatinib and the multi-targeted VEGF and PDGF receptor inhibit or sunitinib malate reversed hypoxia-induced increases in right ventricular systolic pressure (RVSP), right ventricular function and thickening of the medial walls. Mechanistically VEGF/VEGFR and PDGF/PDGFR formed a biological complex. We also showed that PDGF-BBincreasedKLF4 promoter activity transcriptionally activating VEGF expression, which regulates PAEC proliferation; migration; and the cell-cycle transition from G0/G1phase to S phase and G2/M-phase and eventually leads to PAEC angiogenesis Conclusion: Our study indicates that hypoxia-induced angiogenesis of PAECs is associated with increased levels of PDGF-BB/KLF4/VEGF, which contribute to pulmonary vascular remodeling. Overall, our study contributes to a better understanding of PAH pathogenesis. © 2017 The Author(s). Published by S. Karger AG, Basel.

  17. Angiogenetic axis angiopoietins/Tie2 and VEGF in familial breast cancer.

    Science.gov (United States)

    Danza, K; Pilato, B; Lacalamita, R; Addati, T; Giotta, F; Bruno, A; Paradiso, A; Tommasi, S

    2013-08-01

    Angiogenesis leads to the formation of blood vessels from pre-existing ones, allowing tumor growth. Vascular endothelial growth factor (VEGF) and Angiopoietins (Ang-1, Ang-2) have a pivotal role in tumor angiogenesis but few data regarding their role in hereditary breast cancer are available. The aim of the present study was to analyze Ang-1, Ang-2, tyrosine-protein kinase receptor Tie2 and VEGF expression and their correlation in a cohort of familial and sporadic breast cancers in order to verify whether the presence of germline mutations in BRCA may have a role in tumor microenvironment regulation. Tumor samples from a cohort of 41 patients with a first diagnosis and a family history of breast cancer and 19 patients with sporadic breast cancers were enrolled. The expression of Tie2, Ang-1, Ang-2 and VEGF were analyzed by quantitative real-time PCR. Patients harboring BRCA mutations had higher levels of Ang-1 (P=0.05), Ang-2 (P=0.02) and VEGF (P=0.04) mRNA compared with those without BRCA mutations (BRCAX). The same was observed in triple-negative breast cancer (TNBC). Moreover, a positive correlation between Ang-2 and VEGF was found in both the familial breast cancer group (BRCA carriers: r=0.83; P<0.0001 and BRCAX: r=0.58; P=0.008) and in TNBC (r=0.62; P=0.007). The higher levels of Ang-1, Ang-2 and VEGF mRNA found in BRCA carriers and TNBCs suggest that they could be attractive angiogenic therapeutic targets in these breast cancers.

  18. Outer retinal tubulation in diabetic macular edema following anti-VEGF treatment.

    Science.gov (United States)

    Al-Halafi, Ali M

    2015-01-01

    To address the presence and features of outer retinal tubulation (ORT) found in diabetic macular edema (DME) treated with anti-vascular endothelial growth factor (anti-VEGF) and to differentiate between ORT and cystoid DME, which have different plans of management. This was a retrospective review of a total of 514 patients investigated with spectral domain optical coherence tomography (OCT) in patients with diabetic macular edema treated with anti-VEGF. ORT was seen in 12 eyes of 11 patients. The morphologic characteristics of ORT and its progress over time were examined using OCT data. The retinal images were obtained by horizontal and vertical scans to analyze the possible presence of ORT and to explore their morphologic features and location in the retinal layers. ORT was seen in DME treated with anti-VEGF. ORT was shown as round or ovoid hyporeflective spaces with hyperreflective borders on the B-scans, measuring 30 to 120 μm high and 30 to 1775 μm wide. The tubules generally remained stable over time. In a retinal practice specializing in advanced diabetic retinopathy clinic, this ORT was seen in 12 eyes of 11 patients during a 12-month period. ORT presented either after receiving 0.05 mL open-label intravitreal injections of 0.5 mg ranibizumab or 1.25 mg bevacizumab. ORT is found in DME treated with anti-VEGF that may show damage to the outer retina secondary to the severity and chronicity of the DME. ORT may be a result of underlying chronic and severe diabetic macular edema that may occur later possibly secondary to retinal layers rearrangement after several anti-VEGF injections. It is important to differentiate between ORT and cystoids DME. The presence of the ORT entity alone without the presence of DME does not require further anti-VEGF re-injections.

  19. Association of mast cell-derived VEGF and proteases in Dengue shock syndrome.

    Directory of Open Access Journals (Sweden)

    Takahisa Furuta

    Full Text Available BACKGROUND: Recent in-vitro studies have suggested that mast cells are involved in Dengue virus infection. To clarify the role of mast cells in the development of clinical Dengue fever, we compared the plasma levels of several mast cell-derived mediators (vascular endothelial cell growth factor [VEGF], soluble VEGF receptors [sVEGFRs], tryptase, and chymase and -related cytokines (IL-4, -9, and -17 between patients with differing severity of Dengue fever and healthy controls. METHODOLOGY/PRINCIPAL FINDINGS: The study was performed at Children's Hospital No. 2, Ho Chi Minh City, and Vinh Long Province Hospital, Vietnam from 2002 to 2005. Study patients included 103 with Dengue fever (DF, Dengue hemorrhagic fever (DHF, and Dengue shock syndrome (DSS, as diagnosed by the World Health Organization criteria. There were 189 healthy subjects, and 19 febrile illness patients of the same Kinh ethnicity. The levels of mast cell-derived mediators and -related cytokines in plasma were measured by ELISA. VEGF and sVEGFR-1 levels were significantly increased in DHF and DSS compared with those of DF and controls, whereas sVEGFR-2 levels were significantly decreased in DHF and DSS. Significant increases in tryptase and chymase levels, which were accompanied by high IL-9 and -17 concentrations, were detected in DHF and DSS patients. By day 4 of admission, VEGF, sVEGFRs, and proteases levels had returned to similar levels as DF and controls. In-vitro VEGF production by mast cells was examined in KU812 and HMC-1 cells, and was found to be highest when the cells were inoculated with Dengue virus and human Dengue virus-immune serum in the presence of IL-9. CONCLUSIONS: As mast cells are an important source of VEGF, tryptase, and chymase, our findings suggest that mast cell activation and mast cell-derived mediators participate in the development of DHF. The two proteases, particularly chymase, might serve as good predictive markers of Dengue disease severity.

  20. Cellular and molecular aspects of diabetic nephropathy; the role of VEGF-A.

    Science.gov (United States)

    Carranza, Katherine; Veron, Dolores; Cercado, Alicia; Bautista, Noemi; Pozo, Wilson; Tufro, Alda; Veron, Delma

    2015-01-01

    The prevalence of diabetes mellitus increased during the last century and it is estimated that 45% of the patients are not diagnosed. In South America the prevalence of diabetes and chronic kidney disease (CKD) increased, with a great disparity among the countries with respect to access to dialysis. In Ecuador it is one of the main causes of mortality, principally in the provinces located on the coast of the Pacific Ocean. The greatest single cause of beginning dialysis is diabetic nephropathy (DN). Even using the best therapeutic options for DN, the residual risk of proteinuria and of terminal CKD remains high. In this review we indicate the importance of the problem globally and in our region. We analyse relevant cellular and molecular studies that illustrate the crucial significance of glomerular events in DN development and evolution and in insulin resistance. We include basic anatomical, pathophysiological and clinical concepts, with special attention to the role of angiogenic factors such as the vascular endothelial growth factor (VEGF-A) and their relationship to the insulin receptor, endothelial isoform of nitric oxide synthase (eNOS) and angiopoietins. We also propose various pathways that have therapeutic potential in our opinion. Greater in-depth study of VEGF-A and angiopoietins, the state of glomerular VEGF resistance, the relationship of VEGF receptor 2/nephrin, VEGF/insulin receptors/nephrin and the relationship of VEGF/eNOS-NO at glomerular level could provide solutions to the pressing world problem of DN and generate new treatment alternatives. Copyright © 2015. Published by Elsevier España, S.L.U.

  1. P70S6K 1 regulation of angiogenesis through VEGF and HIF-1{alpha} expression

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    Bian, Chuan-Xiu; Shi, Zhumei [Department of Pathology, Cancer Center, Nanjing Medical University, Nanjing 210029 (China); Meng, Qiao; Jiang, Yue; Liu, Ling-Zhi [Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Jiang, Bing-Hua, E-mail: binghjiang@yahoo.com [Department of Pathology, Cancer Center, Nanjing Medical University, Nanjing 210029 (China); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107 (United States)

    2010-07-30

    Research highlights: {yields} P70S6K1 regulates VEGF expression; {yields} P70S6K1 induces transcriptional activation through HIF-1{alpha} binding site; {yields} P70S6K1 regulates HIF-1{alpha}, but not HIF-1{beta} protein expression; {yields} P70S6K1 mediates tumor growth and angiogenesis through HIF-1{alpha} and VEGF expression. -- Abstract: The 70 kDa ribosomal S6 kinase 1 (p70S6K1), a downstream target of phosphoinositide 3-kinase (PI3K) and ERK mitogen-activated protein kinase (MAPK), is an important regulator of cell cycle progression, and cell proliferation. Recent studies indicated an important role of p70S6K1 in PTEN-negative and AKT-overexpressing tumors. However, the mechanism of p70S6K1 in tumor angiogenesis remains to be elucidated. In this study, we specifically inhibited p70S6K1 activity in ovarian cancer cells using vector-based small interfering RNA (siRNA) against p70S6K1. We found that knockdown of p70S6K1 significantly decreased VEGF protein expression and VEGF transcriptional activation through the HIF-1{alpha} binding site at its enhancer region. The expression of p70S6K1 siRNA specifically inhibited HIF-1{alpha}, but not HIF-1{beta} protein expression. We also found that p70S6K1 down-regulation inhibited ovarian tumor growth and angiogenesis, and decreased cell proliferation and levels of VEGF and HIF-1{alpha} expression in tumor tissues. Our results suggest that p70S6K1 is required for tumor growth and angiogenesis through HIF-1{alpha} and VEGF expression, providing a molecular mechanism of human ovarian cancer mediated by p70S6K1 signaling.

  2. Expressions and clinical significance of COX-2, VEGF-C, and EFGR in endometrial carcinoma.

    Science.gov (United States)

    Cai, Shengnan; Zhang, Yue-Xiang; Han, Ke; Ding, Yi-Qian

    2017-07-01

    The article is to study the expressions of COX-2, VEGF-C, and EGFR in endometrial carcinoma as well as its clinical significances. Clinical data of 183 patients with endometrial carcinoma who received surgery as initial treatment in the Nanjing Drum Tower Hospital Affiliated to the Nanjing University Medical School and the Nantong Maternal and Child Health Hospital Affiliated to the Nantong University from January 2005 to December 2010 were retrospectively investigated; 152 out of the 183 patients were closely followed up. Expressions of COX-2, VEGF-C, and EGFR proteins in 152 endometrial carcinoma samples were detected by immunohistochemical S-P assay. A 5-year survival rate of 152 patients was 81.56% (124/152). Positive COX-2 expression rate was 67.76% (103/152), and its positive expression was related to FIGO stage, differentiation degree, and myometrial invasion depth of patients (P  0.05). Positive expression rates of VEGF-C and EGFR were 64.47% (98/152) and 82.24% (125/152), respectively, and their positive expression was associated with FIGO stage, differentiation degree, myometrial invasion depth, and lymphatic metastasis (P  0). Patient prognosis was associated with the FIGO stage, differentiation degree, and myometrial invasion depth of tumors, as well as the presence or absence of lymph node metastasis (P  0.05). COX-2, VEGF-C, and EGFR are of significance for determining the FIGO stage, differentiation degree, and myometrial invasion depth of endometrial carcinoma, of which VEGF-C and EGFR are important in determining whether tumors metastasize to lymph nodes. Combined detection of COX-2, EGFR, and VEGF-C can be used as the indices for early diagnosis, recurrence prediction, and outcome evaluation for patients with endometrial carcinoma.

  3. The association between vascular endothelial growth factor (VEGF) +405G>C genetic polymorphism and endometriosis.

    Science.gov (United States)

    Fang, Fang; Gong, Lili; Wang, Xiaojuan; Zhang, Ling

    2015-09-01

    The vascular endothelial growth factor (VEGF) is one of the most important candidate genes for the development of endometriosis, and VEGF genetic polymorphisms might be potentially associated with endometriosis risk. However, the results still remain controversial. The objective of this study aimed to perform a comprehensive meta-analysis to explore a better understanding of the effects of VEGF +405G>C genetic polymorphism on the risk of endometriosis. A total of eleven eligible studies were eventually identified in this meta-analysis, including 2829 endometriosis cases and 2947 controls. In the overall analysis, no significant association between the VEGF +405G>C genetic polymorphism and the risk of endometriosis was detected in all genetic models (for homozygote comparison [CC versus vs. GG]: OR = 1.21, 95% CI 0.67-2.19, P = 0.537; for heterozygote comparison [CG vs. GG]: OR = 1.16, 95% CI 0.86-1.56, P = 0.348; for dominant comparison CC/CG vs. GG: OR = 1.10, 95% CI 0.93-1.30, P = 0.263; for recessive comparison [CC vs. CG/GG]: OR = 1.03, 95% CI 0.73-1.47, P = 0.857; allele comparison [C vs. G]: OR = 0.99, 95% CI 0.70-1.40, P = 0.962). In the subgroup analysis by ethnicities, there was no significant association between VEGF +405G>C genetic polymorphism and endometriosis risk in Asians and/or Caucasians under all genetic models (all P-values >0.05). No publication bias was observed in this study. This meta-analysis supports that the VEGF +405G>C genetic polymorphism is not significant associated with the risk of endometriosis. © 2015 by the Society for Experimental Biology and Medicine.

  4. Recombinant human erythropoietin pretreatment alleviates renal glomerular injury induced by cardiopulmonary bypass by reducing transient receptor potential channel 6-nuclear factor of activated T-cells pathway activation.

    Science.gov (United States)

    Liu, Xiaoming; Zhang, Tingting; Xia, Weiliang; Wang, Yingwei; Ma, Ke

    2013-09-01

    Acute renal injury after cardiopulmonary bypass is common and associated with high mortality. We aimed to demonstrate the glomerular protective effects of recombinant human erythropoietin using an in vivo rat cardiopulmonary bypass model and to explore the possible mechanism. Dose-related renal protective effects of recombinant human erythropoietin were studied in phase I. Male Sprague Dawley rats were randomly divided into 5 groups: sham group, cardiopulmonary bypass group, and 3 recombinant human erythropoietin-treated cardiopulmonary bypass groups (bolus doses of 500, 3000, and 5000 U/kg 24 hours before surgery). Blood and urine samples were collected just before surgery and at 2, 4, 24, 48, and 72 hours after surgery. In phase II, rats were divided into 3 groups: sham group, cardiopulmonary bypass group, and 5000 U/kg recombinant human erythropoietin group. Kidneys were harvested at 4, 24, 48, and 72 hours after surgery. Ultra-organization of glomeruli was observed. Glomerular transient receptor potential channel 6 (TRPC6) expression was studied by immunofluorescence and Western blot. Nuclei nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1) activity was analyzed by enzyme-linked immunosorbent assays and electrophoretic mobility shift assay. Pretreatment of 5000 U/kg recombinant human erythropoietin decreased the urine protein (72 hours: 7.82 ± 1.13 g/L vs 11.28 ± 1.73 g/L), serum creatinine (72 hours: 35.0 ± 3.5 μmol/L vs 60.7 ± 7.6 μmol/L), and cystatin-C (2 hours: 336.5 ± 28.2 μg/L vs 452.6 ± 63.8 μg/L) compared with the control group (P Cardiopulmonary bypass induced morphologic abnormalities of podocyte foot processes and slit diaphragms, which was improved by recombinant human erythropoietin. Furthermore, recombinant human erythropoietin significantly relieved glomerular TRPC6 increase and NFATc1 activation induced by cardiopulmonary bypass. Pretreatment of 5000 U/kg recombinant human erythropoietin elicited

  5. Development and characterization of a human antibody reference panel against erythropoietin suitable for the standardization of ESA immunogenicity testing.

    Science.gov (United States)

    Mytych, Daniel T; Barger, Troy E; King, Chadwick; Grauer, Stephanie; Haldankar, Raj; Hsu, Eric; Wu, Michelle Min; Shiwalkar, Mukta; Sanchez, Sergio; Kuck, Andrew; Civoli, Francesca; Sun, Jilin; Swanson, Steven J

    2012-08-31

    Recombinant human erythropoietin (EPO) has been used therapeutically for more than two decades in the treatment of anemia. Although EPO is generally well tolerated, in rare cases, patients have developed anti-EPO antibodies that can negatively impact safety and efficacy. Therefore, the detection of antibodies against EPO is a regulatory requirement during clinical development and post-approval. Although it is a rare phenomenon, antibody-mediated pure red cell aplasia (PRCA) is a serious complication than can result from antibodies that develop and neutralize EPO as well as endogenous erythropoietin. Currently, there are no universally accepted analytical methods to detect the full repertoire of binding and neutralizing anti-EPO antibodies. A number of different methods that differ in terms of antibodies detected and assay sensitivities are used by different manufacturers. There is also a lack of antibody reference reagents, and therefore no consistent basis for detecting and measuring anti-EPO antibodies. Reference reagents, with established ranges, are essential to monitor the safety and efficacy of all erythropoiesis-stimulating agents (ESAs) structurally related to human erythropoietin. This is the first report of the development and characterization of a panel of fully human antibodies against EPO suitable as reference reagents. The characteristics of antibodies within the panel were selected based on the prevalence of non-neutralizing IgG and IgM antibodies in non-PRCA patients and neutralizing IgG antibodies, including IgG1 and IgG4, in antibody-mediated PRCA subjects. The reference panel includes antibodies of high- and low-affinity with binding specificity to neutralizing and non-neutralizing erythropoietin epitopes. The subclass of human antibodies in this reference panel includes an IgG1, IgG2, and IgG4, as well as an IgM isotype. This antibody panel could help select appropriate immunogenicity assays, guide validation, and monitor assay performance

  6. Brain and skin do not contribute to the systemic rise in erythropoietin during acute hypoxia in humans

    DEFF Research Database (Denmark)

    Rasmussen, Peter; Nordsborg, Nikolai; Taudorf, Sarah

    2012-01-01

    Erythropoietin (EPO) preserves arterial oxygen content by controlling red blood cell and plasma volumes. Synthesis of EPO was long thought to relate inversely to renal oxygenation, but in knockout mice, brain and skin have been identified as essential for the acute hypoxic EPO response. Whether...... hypoxia with or without breathing oxygen-enriched air to ensure systemic normoxemia. With 9 h of hypoxia, arterial EPO increased (from 6.0±2.2 to 22.0±6.0 mU/ml, n=11, P...

  7. Effects of continuous erythropoietin receptor activator in sepsis-induced acute kidney injury and multi-organ dysfunction.

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    Camila E Rodrigues

    Full Text Available BACKGROUND: Despite advances in supportive care, sepsis-related mortality remains high, especially in patients with acute kidney injury (AKI. Erythropoietin can protect organs against ischemia and sepsis. This effect has been linked to activation of intracellular survival pathways, although the mechanism remains unclear. Continuous erythropoietin receptor activator (CERA is an erythropoietin with a unique pharmacologic profile and long half-life. We hypothesized that pretreatment with CERA would be renoprotective in the cecal ligation and puncture (CLP model of sepsis-induced AKI. METHODS: RATS WERE RANDOMIZED INTO THREE GROUPS: control; CLP; and CLP+CERA (5 µg/kg body weight, i.p. administered 24 h before CLP. At 24 hours after CLP, we measured creatinine clearance, biochemical variables, and hemodynamic parameters. In kidney tissue, we performed immunoblotting--to quantify expression of the Na-K-2Cl cotransporter (NKCC2, aquaporin 2 (AQP2, Toll-like receptor 4 (TLR4, erythropoietin receptor (EpoR, and nuclear factor kappa B (NF-κB--and immunohistochemical staining for CD68 (macrophage infiltration. Plasma interleukin (IL-2, IL-1β, IL-6, IL-10, interferon gamma, and tumor necrosis factor alpha were measured by multiplex detection. RESULTS: Pretreatment with CERA preserved creatinine clearance and tubular function, as well as the expression of NKCC2 and AQP2. In addition, CERA maintained plasma lactate at normal levels, as well as preserving plasma levels of transaminases and lactate dehydrogenase. Renal expression of TLR4 and NF-κB was lower in CLP+CERA rats than in CLP rats (p<0.05 and p<0.01, respectively, as were CD68-positive cell counts (p<0.01, whereas renal EpoR expression was higher (p<0.05. Plasma levels of all measured cytokines were lower in CLP+CERA rats than in CLP rats. CONCLUSION: CERA protects against sepsis-induced AKI. This protective effect is, in part, attributable to suppression of the inflammatory response.

  8. Physical disruption of cell-cell contact induces VEGF expression in RPE cells.

    Science.gov (United States)

    Farjood, Farhad; Vargis, Elizabeth

    2017-01-01

    To investigate the role of RPE cell-cell contact in vascular endothelial growth factor (VEGF) protein expression in cultures of primary human RPE (hRPE) cells and a human RPE cell line (ARPE-19). Two in vitro methods, scratching and micropatterning, were used to control the physical dissociation of RPE cell-cell junctions. Scratching was performed by scoring monolayers of RPE cells with a cell scraper. Micropatterning was achieved by using a stencil patterning method. Extracellular VEGF expression was assessed by using an enzyme-linked immunosorbent assay (ELISA) kit. Immunocytochemistry (ICC) was performed to visualize the expression and localization of VEGF and intercellular proteins zonula occludens-1 (ZO-1), N-cadherin, β-catenin, and claudin-1 in RPE cultures. Higher expression of VEGF protein by cells on the edges of the scratched RPE layers was confirmed with ICC in short-term (1 day after confluency) and long-term (4 weeks after confluency) cultures. According to the ICC results, ZO-1, N-cadherin, β-catenin, and claudin-1 successfully localized to cell-cell junctions in long-term cultures of ARPE-19 and hRPE cells. However, unlike N-cadherin, β-catenin, and claudin-1, only ZO-1 localized junctionally in short-term cultures of both cell types. Moreover, removing cell-cell junctions by scratching resulted in the delocalization of ZO-1 from tight junctions to the cytoplasm. The loss of tight junction formation and the accumulation of ZO-1 in the cytoplasm correlated with increased VEGF expression. Micropatterning RPE cells on different sized circular patterns produced varying concentrations of cells with lost cell-cell junctions. When fewer cells formed intercellular junctions, increased extracellular VEGF secretion was observed from the ARPE-19 and hRPE cells. VEGF expression increases after physical disruption of RPE cell-cell connections. This increase in VEGF expression correlates with the loss of intercellular junctions and the localization of ZO-1 in

  9. Dual delivery of VEGF and ANG-1 in ischemic hearts using an injectable hydrogel.

    Science.gov (United States)

    Rufaihah, Abdul Jalil; Johari, Nurul Azizah; Vaibavi, Srirangam Ramanujam; Plotkin, Marian; Di Thien, Do Thi; Kofidis, Theodoros; Seliktar, Dror

    2017-01-15

    Acute myocardial infarction (MI) caused by ischemia is the most common cause of cardiac dysfunction. While growth factor therapy is promising, the retention in the highly vascularized myocardium is limited and prevents sustained activation needed for adequate cellular responses. Here, we demonstrated the use of polyethylene glycol-fibrinogen (PF) hydrogels for sustained dual delivery of vascular endothelial growth factor (VEGF) and angiopoietin-1 (ANG-1) to enhance myocardial repair and function. VEGF and ANG-1 were incorporated in PF hydrogels and their in vitro characteristics were studied. Acute MI was generated in a rodent model with rats randomly assigned to 4 groups; sham, saline, PF and PF-VEGF-ANG1 (n=10 each group). Saline or hydrogel was injected in infarct and peri-infarct areas of the myocardium. After 4weeks, myocardial function was assessed using echocardiography. Tissue samples were harvested for Hematoxylin and Eosin, Masson Trichrome and capillary staining to assess the extent of fibrotic scar and arteriogenesis. Both VEGF and ANG-1 were released in a sustained and controlled manner over 30days. PF-VEGF-ANG1 treated animals showed the best improvement in cardiac function, highest degree of cardiac muscle preservation, and arteriogenesis. This study demonstrates that PF hydrogels can simultaneously provide mechanical support to attenuate adverse myocardial remodelling, and a pro-angiogenic benefit from the sustained VEGF and ANG1 delivery that culminates in a restorative effect following MI. The utility of this synergistic, biomaterial-based growth factor delivery may have clinical implications in the prevention of post-MI cardiac dysfunction. Acute myocardial infarction (MI) caused by ischemia is the most common cause of cardiac dysfunction. Here, we demonstrated the use of polyethylene glycol-fibrinogen (PF) hydrogels for sustained dual delivery of vascular endothelial growth factor (VEGF) and angiopoietin-1 (ANG-1) to enhance myocardial repair

  10. VEGFR2-mediated vascular dilation as a mechanism of VEGF-induced anemia and bone marrow cell mobilization.

    Science.gov (United States)

    Lim, Sharon; Zhang, Yin; Zhang, Danfang; Chen, Fang; Hosaka, Kayoko; Feng, Ninghan; Seki, Takahiro; Andersson, Patrik; Li, Jingrong; Zang, Jingwu; Sun, Baocun; Cao, Yihai

    2014-10-23

    Molecular mechanisms underlying tumor VEGF-induced host anemia and bone marrow cell (BMC) mobilization remain unknown. Here, we report that tumor VEGF markedly induced sinusoidal vasculature dilation in bone marrow (BM) and BMC mobilization to tumors and peripheral tissues in mouse and human tumor models. Unexpectedly, anti-VEGFR2, but not anti-VEGFR1, treatment completely blocked VEGF-induced anemia and BMC mobilization. Genetic deletion of Vegfr2 in endothelial cells markedly ablated VEGF-stimulated BMC mobilization. Conversely, deletion of the tyrosine kinase domain from Vegfr1 gene (Vegfr1(TK-/-)) did not affect VEGF-induced BMC mobilization. Analysis of VEGFR1(+)/VEGFR2(+) populations in peripheral blood and BM showed no significant ratio difference between VEGF- and control tumor-bearing animals. These findings demonstrate that vascular dilation through the VEGFR2 signaling is the mechanism underlying VEGF-induced BM mobilization and anemia. Thus, our data provide mechanistic insights on VEGF-induced BMC mobilization in tumors and have therapeutic implications by targeting VEGFR2 for cancer therapy. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Potentiated Osteoinductivity via Cotransfection with BMP-2 and VEGF Genes in Microencapsulated C2C12 Cells

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    Yang Shen

    2015-01-01

    Full Text Available Microcapsules with entrapped cells hold great promise for repairing bone defects. Unfortunately, the osteoinductivity of microcapsules has been restricted by many factors, among which the deficiency of functional proteins is a significant priority. We potentiated the osteoinductivity of microencapsulated cells via cotransfection with BMP-2 and VEGF genes. Various tissue-derived mesenchymal stem cells and cell lines were compared for BMP-2 and VEGF cotransfection. Ethidium bromide (EB/Calcein AM staining revealed that all of the cell categories could survive for 4 weeks after microencapsulation. An ELISA assay indicated that all microencapsulated BMP-2 or VEGF transfected cells could secrete gene products constitutively for 1 month. Particularly, the recombinant microencapsulated C2C12 cells released the most desirable level of BMP-2 and VEGF. Further experiments demonstrated that microencapsulated BMP-2 and VEGF cotransfected C2C12 cells generated both BMP-2 and VEGF for 4 weeks. Additionally, the cotransfection of BMP-2 and VEGF in microencapsulated C2C12 cells showed a stronger osteogenic induction against BMSCs than individual BMP-2-transfected microencapsulated C2C12 cells. These results demonstrated that the cotransfection of BMP-2 and VEGF into microencapsulated C2C12 cells is of potent utility for the potentiation of bone regeneration, which would provide a promising clinical strategy for cellular therapy in bone defects.

  12. Penduliflaworosin, a Diterpenoid from Croton crassifolius, Exerts Anti-Angiogenic Effect via VEGF Receptor-2 Signaling Pathway

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    Yeyin Liang

    2017-01-01

    Full Text Available Anti-angiogenesis targeting vascular endothelial growth factor receptor-2 (VEGFR-2 has been considered as an important strategy for cancer therapy. Penduliflaworosin is a diterpenoid isolated from the plant Croton crassifolius. Our previous study showed that this diterpenoid possesses strong anti-angiogenic activity by inhibiting vessel formation in zebrafish. This study was conducted to further investigate the anti-angiogenic activity and mechanism of penduliflaworosin. Results revealed that penduliflaworosin significantly inhibited VEGF-induced angiogenesis processes including proliferation, invasion, migration, and tube formation of human umbilical vein endothelial cells (HUVECs. Moreover, it notably inhibited VEGF-induced sprout formation of aortic rings and blocked VEGF-induced vessel formation in mice. Western blotting studies showed that penduliflaworosin inhibited phosphorylation of the VEGF receptor-2 and its downstream signaling mediators in HUVECs, suggesting that the anti-angiogenic activity was due to an interference with the VEGF/VEGF receptor-2 pathway. In addition, molecular docking simulation indicated that penduliflaworosin could form hydrogen bonds within the ATP-binding region of the VEGF receptor-2 kinase unit. Finally, cytotoxicity assay showed that penduliflaworosin possessed little toxicity toward both cancer and normal cells. Taken together, our findings demonstrate that penduliflaworosin exerts its anti-angiogenic effect via the VEGF receptor-2 signaling pathway. The anti-angiogenic property and low cytotoxicity of penduliflaworosin suggest that it may be useful in cancer treatments.

  13. "EFFECT OF HIGH VERSUS LOW DOSES OF HUMAN RECOMBINANT ERYTHROPOIETIN ON THE ANEMIA OF PREMATURITY"

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    A. Mohammadzadeh

    2005-05-01

    Full Text Available Recombinant human erythropoietin (rh-EPO is known to accelerate erythropoiesis in preterm infants. The purpose of this study was to compare the effectiveness of early treatment with two doses of rh-EPO (high vs. low dose in the management of anemia of prematurity. Twenty preterm infants with hematocrit (Hct < 30% when infant’s age was between 2 to 3 weeks after birth or Hct <25% when infant’s age was more than 3 weeks after birth, were divided randomly in two groups, each group including 10 babies. Infants in high dose group received 500 u/kg rh-EPO twice per week and the low dose group received 500 u/kg rh-EPO weekly. All infants were fed human milk supplemented with enteral iron. Hematocrit and reticulocyte counts were determined for each infant at the start of the study, 3 days after start of treatment and one week after the end of treatment. The means of gestational age in high dose and low dose groups were 31.4 ± 2.2 and 31.3±2.0 weeks, respectively. Means of birth weight in high dose and low dose groups were 1366 ± 243 and 1438±249 gr, respectively. The two groups were significantly different in reticulocyte count at 3 days after treatment (P = 0.047 and in hematocrit at the end of study (P < 0.0001. We concluded the early treatment of anemia of prematurity with high dose rh-EPO with supplemental iron significantly increases hematocrit and reticulocyte in preterm infants and reduce the need for blood transfusion in these high risk neonates.

  14. Lenalidomide induces lipid raft assembly to enhance erythropoietin receptor signaling in myelodysplastic syndrome progenitors.

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    Kathy L McGraw

    Full Text Available Anemia remains the principal management challenge for patients with lower risk Myelodysplastic Syndromes (MDS. Despite appropriate cytokine production and cellular receptor display, erythropoietin receptor (EpoR signaling is impaired. We reported that EpoR signaling is dependent upon receptor localization within lipid raft microdomains, and that disruption of raft integrity abolishes signaling capacity. Here, we show that MDS erythroid progenitors display markedly diminished raft assembly and smaller raft aggregates compared to normal controls (p = 0.005, raft number; p = 0.023, raft size. Because lenalidomide triggers raft coalescence in T-lymphocytes promoting immune synapse formation, we assessed effects of lenalidomide on raft assembly in MDS erythroid precursors and UT7 cells. Lenalidomide treatment rapidly induced lipid raft formation accompanied by EpoR recruitment into raft fractions together with STAT5, JAK2, and Lyn kinase. The JAK2 phosphatase, CD45, a key negative regulator of EpoR signaling, was displaced from raft fractions. Lenalidomide treatment prior to Epo stimulation enhanced both JAK2 and STAT5 phosphorylation in UT7 and primary MDS erythroid progenitors, accompanied by increased STAT5 DNA binding in UT7 cells, and increased erythroid colony forming capacity in both UT7 and primary cells. Raft induction was associated with F-actin polymerization, which was blocked by Rho kinase inhibition. These data indicate that deficient raft integrity impairs EpoR signaling, and provides a novel strategy to enhance EpoR signal fidelity in non-del(5q MDS.

  15. Cell therapy with human renal cell cultures containing erythropoietin-positive cells improves chronic kidney injury.

    Science.gov (United States)

    Yamaleyeva, Liliya M; Guimaraes-Souza, Nadia K; Krane, Louis S; Agcaoili, Sigrid; Gyabaah, Kenneth; Atala, Anthony; Aboushwareb, Tamer; Yoo, James J

    2012-05-01

    New therapeutic strategies for chronic kidney disease (CKD) are necessary to offset the rising incidence of CKD and donor shortage. Erythropoietin (EPO), a cytokine produced by fibroblast-like cells in the kidney, has recently emerged as a renoprotective factor with anti-inflammatory, antioxidant properties. This study (a) determined whether human renal cultures (human primary kidney cells [hPKC]) can be enriched in EPO-positive cells (hPKC(F+)) by using magnetic-bead sorting; (b) characterized hPKC(F+) following cell separation; and (c) established that intrarenal delivery of enriched hPKC(F+) cells would be more beneficial in treatment of renal injury, inflammation, and oxidative stress than unsorted hPKC cultures in a chronic kidney injury model. Fluorescence-activated cell sorting analysis revealed higher expression of EPO (36%) and CD73 (27%) in hPKC(F+) as compared with hPKC. After induction of renal injury, intrarenal delivery of hPKC(F+) or hPKC significantly reduced serum creatinine, interstitial fibrosis in the medulla, and abundance of CD68-positive cells in the cortex and medulla (p renal cortex and decreased urinary albumin (3.5-fold) and urinary tubular injury marker kidney injury molecule 1 (16-fold). hPKC(F+) also significantly reduced levels of renal cortical monocyte chemotactic protein 1 (1.8-fold) and oxidative DNA marker 8-hydroxy-deoxyguanosine (8-OHdG) (2.4-fold). After 12 weeks, we detected few injected cells, which were localized mostly to the cortical interstitium. Although cell therapy with either hPKC(F+) or hPKC improved renal function, the hPKC(F+) subpopulation provides greater renoprotection, perhaps through attenuation of inflammation and oxidative stress. We conclude that hPKC(F+) may be used as components of cell-based therapies for degenerative kidney diseases.

  16. Effects of L-Carnitine Added to Erythropoietin in Anemic Chronic Renal Failure Patients on Hemodialysis.

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    N Taheri

    2006-10-01

    Full Text Available Introduction: Chronic renal disease (C.R.D is a pathophysiological process due to progressive and irreversible decrease in number and function of nephrons in the kidney. Anemia is one of the most important complications in CRD patients. Anemia is caused mainly due to diminished production of erythropoietin (EPO, which is treated by weekly injection of the EPO. L-carnitine added to EPO can increase the efficacy of EPO. Methods: Present study, from March 2003 until September 2004 (18 months, evaluates the effects of L-carnitine added to EPO in 30 patients at Shaheed Rahnemon hemodialysis center of Yazd. Each patient was administered one oral table (250 mg of L-carnitine, twice a day along with EPO for 90 days. EPO was in the form of injection 2000 iu/sc after dialysis.(three times per week. One questionnaire was completed for each patient, which included demographic characteristics, type of disease, duration of the hemodialysis, Hb and Hct levels, transferrin saturation and ferritin levels. Hb ,Hct and transferrin saturations were measured on days 1, 45 and 90. Results were analyzed by paired t test and analysis of variance. Results: Results of this study showed that the mean Hb levels and Hct were significantly raised up to 1.1 mg/dl (P.value<0.001 and 2.7% (P.Value<0.001, respectively. In addition, significant decrease of 5.75% in transferrin (P.Value< 0.001 and 121ng/ml in ferritin levels (P.Value< 0.001 was observed. Efficacy of EPO plus L-carnitine was affected only by duration of hemodialysis and not by age, sex or causes of CRD. Conclusion: L-carnitine added to EPO increases the efficacy of EPO after 3 months.

  17. Erythropoietin enhances nerve repair in anti-ganglioside antibody-mediated models of immune neuropathy.