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Sample records for ca9 erythropoietin vegf

  1. Expression patterns of the hypoxia-related genes osteopontin, CA9, erythropoietin, VEGF and HIF-1α in human glioma in vitro and in vivo

    International Nuclear Information System (INIS)

    Said, Harun M.; Hagemann, Carsten; Staab, Adrian; Stojic, Jelena; Kuehnel, Siglinde; Vince, Giles H.; Flentje, Michael; Roosen, Klaus; Vordermark, Dirk

    2007-01-01

    Background and purpose: To identify molecular markers of tumor hypoxia and potential therapeutic targets in glioblastoma (GBM), we investigated the hypoxia-related expression of osteopontin (OPN), carbonic anhydrase 9 (CA9), erythropoietin (EPO), vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α (HIF-1α) in vitro in human GBM cell lines and in vivo in human tumor samples of GBM, compared to low-grade astrocytoma (LGA). Materials and methods: Expression of the hypoxia-induced genes OPN, CA9, EPO, VEGF and HIF-1α was analyzed in three GBM cell lines, GaMG, U373 and U251, under in vitro hypoxia (1, 6 or 24 h at 5%, 1% or 0.1% O 2 ) and in tumor samples from two patient groups with LGA and GBM (n = 15 each), at the mRNA level (semiquantitative RT-PCR). Selected conditions and representative tumor samples were also evaluated at the protein level by Western blot. Results: OPN and CA9 mRNA was most consistently upregulated in relation to severity and duration of in vitro hypoxia. In tumor samples, mean expression levels (LGA vs. GBM, normalized to mean expression in normal brain) were 1.71 vs. 4.57 (p < 0.001) for OPN, 1.11 vs. 3.35 (p < 0.001) for CA9, 2.79 vs. 5.28 (not significant, n.s.) for Epo, 1.13 vs. 2.0 (p = 0.007) for VEGF and 0.97 vs. 0.97 (n.s.) for HIF-1α. In tumor samples, GBM showed a particularly strong protein expression of OPN. Conclusions: Among a panel of known hypoxia-inducible genes, OPN and CA9 emerge as most consistently induced by in vitro hypoxia in human GBM cell lines and most specifically expressed in patient GBM tumor tissue, rendering these two genes attractive targets for hypoxia-directed treatment approaches

  2. Erythropoietin

    DEFF Research Database (Denmark)

    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 mo...

  3. Erythropoietin radioimmunoassay studies

    International Nuclear Information System (INIS)

    Garcia, J.F.

    1982-01-01

    A highly sensitive radioimmunoassay capable of measuring erythropoietin concentrations in very small amounts of serum as been developed. After establishing normal human values on a large series of serum samples, serum samples from patients with polycythemia vera and patients with secondary polycythemia were obtained and the erythropoietin concentrations measured

  4. Radioimmunoassay of erythropoietin

    Energy Technology Data Exchange (ETDEWEB)

    Goldwasser, E; Sherwood, J B [Chicago Univ., IL (USA). Dept. of Biochemistry

    1981-07-01

    A brief review of the historical development of the radioimmunoassay (RIA) for serum erythropoietin is given. It has been shown that there is reasonable agreement between the results obtained by RIA and those obtained by the previously used bioassay. By RIA, a mean normal serum titre of 18 mu/ml erythropoietin has been determined in a study of 445 individuals. Serum erythropoietin results for patients with polycythaemia vera have not been shown to be significantly different from normal values but in patients with secondary polycythaemia, serum titres averaging 94 mu/ml have been found. The predicted physiological changes in erythropoietin titre have also been demonstrated in humans using the RIA; increasing after bleeding and decreasing after red cell administration. Studies of erythropoietin levels in experimental animals have shown that, with the particular antiserum used, the sensitivity of the RIA is markedly reduced.

  5. 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

    OBJECTIVE: Circulating erythropoietin (EPO) and vascular endothelial growth factor (VEGF) increase during hypoglycaemia and may represent protective hormonal counter-regulatory responses. We tested the hypothesis that low levels of EPO and VEGF are associated with a higher frequency of severe....... 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...... 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...

  6. Erythropoietin and radiotherapy; Erythropoietine et radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Le Fur, E.; Albarghach, M.N.; Pradier, O. [CHU de Morvan, Dept. de radiotherapie, 29 - Brest (France)

    2010-01-15

    Erythropoietin (E.P.O.) is a glycoprotein hormone. This hormone is a growth factor for red blood cells precursors in the bone marrow. The decrease of oxygen partial pressure, a reduced number of erythrocytes caused by bleeding or excessive destruction, or increased tissues oxygen requirements lead to increased secretion of E.P.O.. Its action takes place on bone marrow erythroblastic cells through specific receptors. E.P.O. stimulates the proliferation of red cell precursors stem cells in the bone marrow, thus increasing their production in one to two weeks. The effectiveness of E.P.O. at increasing haemoglobin and improving patients quality of life has been demonstrated by several studies. However, its use in radiotherapy remains controversial. While tumour hypoxia caused by anaemia is a factor of radio resistance and thus a source of local failure, tumour expression of E.P.O. receptors presents a significant risk for tumour progression and neo-angiogenesis, which would be increased during the administration of E.P.O.. The purpose of this article is to answer the question: is there a place for E.P.O. in combination with radiotherapy in the management of cancer?

  7. [Overview of erythropoietin].

    Science.gov (United States)

    Lacombe, C; Mayeux, P; Casadevall, N

    1991-01-01

    Erythropoietin (Epo) is a glycoprotein that promotes the proliferation and differentiation of erythrocyte precursors. The major site of Epo production is the kidney and the liver is the main extra renal site of Epo production. Epo producing cells were identified by in situ hybridization, in the kidney, they are peritubular cells, most likely endothelial cells of the cortex and outer medulla; in the liver, they are mainly hepatocytes. The Epo secretion is stimulated by hypoxia, which is detected by an oxygen sensor. The Epo receptor is a multimeric protein, one chain which binds Epo has been cloned. However the structure of the Epo receptor is still puzzling, and one or more accessory chains remain to be identified. Since the clonage of the Epo gene, recombinant Epo has been available and allowed the treatment of patients with renal diseases with a constant efficacy.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Role of Erythropoietin in Renal Anemia Therapy

    African Journals Online (AJOL)

    of erythropoietin and others drugs in renal anemia treatment, as well as the cause of erythropoietin resistance. .... mouth health, atrophy prevention, prevention of artery hardening ... Secondary hyperthyroidism can lead to osteitis fibrosa ...

  10. Erythropoietin in radiotherapy

    International Nuclear Information System (INIS)

    Guttenburger, R.

    2003-01-01

    A high blood hemoglobin level is an independent factor for good prognosis as demonstrated in retrospective and prospective studies in a number of cancer sites. However, there is still debate on how hemoglobin affects outcome after radiotherapy. The issues are: 1. How about the predictive power and the magnitude of effect in various tumor entities? 2. Are all potential mechanisms for the hemoglobin effect considered? 3. Do EPO receptors found on tumor and normal cells outside the bone marrow play a role? Experimental and clinical data on anemia and its treatment have been extensively discussed. So far, the means to manipulate the hemoglobin level, their indication and administration are to be clarified. The issues are: 1. Why does transfusion not improve prognosis? 2. What have we learned from trials using EPO to stimulate endogenous Hb production? 3. What are the potential pitfalls of correcting anemia with EPO? 4. What is the optimal design of EPO-RT trials? Although there are still more questions than answers, the therapeutic potential of erythropoietin is of considerable interest to radiation oncologists. This report gives a summary reviewing the topic and ends on a note of caution: Mild anemia in cancer patients is no indication to use EPO outside clinical trials

  11. Erythropoietin and radiotherapy

    International Nuclear Information System (INIS)

    Le Fur, E.; Albarghach, M.N.; Pradier, O.

    2010-01-01

    Erythropoietin (E.P.O.) is a glycoprotein hormone. This hormone is a growth factor for red blood cells precursors in the bone marrow. The decrease of oxygen partial pressure, a reduced number of erythrocytes caused by bleeding or excessive destruction, or increased tissues oxygen requirements lead to increased secretion of E.P.O.. Its action takes place on bone marrow erythroblastic cells through specific receptors. E.P.O. stimulates the proliferation of red cell precursors stem cells in the bone marrow, thus increasing their production in one to two weeks. The effectiveness of E.P.O. at increasing haemoglobin and improving patients quality of life has been demonstrated by several studies. However, its use in radiotherapy remains controversial. While tumour hypoxia caused by anaemia is a factor of radio resistance and thus a source of local failure, tumour expression of E.P.O. receptors presents a significant risk for tumour progression and neo-angiogenesis, which would be increased during the administration of E.P.O.. The purpose of this article is to answer the question: is there a place for E.P.O. in combination with radiotherapy in the management of cancer?

  12. Anti-VEGF therapy in the management of retinopathy of prematurity: what we learn from representative animal models of oxygen-induced retinopathy.

    Science.gov (United States)

    Wang, Haibo

    2016-01-01

    Retinopathy of prematurity (ROP) remains a leading cause of childhood blindness, affecting infants born prematurely. ROP is characterized by the onset of delayed physiological retinal vascular development (PRVD) and followed by pathologic neovascularization into the vitreous instead of the retina, called intravitreal neovascularization (IVNV). Therefore, the therapeutic strategy for treating ROP is to promote PRVD and inhibit or prevent IVNV. Vascular endothelial growth factor (VEGF) plays an important role in the pathogenesis of ROP. There is a growing body of studies testing the use of anti-VEGF agents as a treatment for ROP. Intravitreal anti-VEGF treatment for ROP has potential advantages compared with laser photocoagulation, the gold standard for the treatment of severe ROP; however, intravitreal anti-VEGF treatment has been associated with reactivation of ROP and suppression of systemic VEGF that may affect body growth and organ development in preterm infants. Therefore, it is important to understand the role of VEGF in PRVD and IVNV. This review includes the current knowledge of anti-VEGF treatment for ROP from animal models of oxygen-induced retinopathy (OIR), highlighting the importance of VEGF inhibition by targeting retinal Müller cells, which inhibits IVNV and permits PRVD. The signaling events involved in mediating VEGF expression and promoting VEGF-mediated angiogenesis, including hypoxia-dependent signaling, erythropoietin/erythropoietin receptor-, oxidative stress-, beta-adrenergic receptor-, integrin-, Notch/Delta-like ligand 4- and exon guidance molecules-mediated signaling pathways, are also discussed.

  13. Biology of erythropoietin.

    Science.gov (United States)

    Lacombe, C; Mayeux, P

    1998-08-01

    Erythropoietin (Epo) controls the proliferation, differentiation and survival of the erythroid progenitors. This cytokine was cloned in 1985 and rapidly became used for treatment of anemia of renal failure, opening the way to the first clinical trials of a hematopoietic growth factor. The clonage of one chain of the Epo receptor followed in 1989, thereby opening the research on intracellular signal transduction induced by Epo. Epo is synthesized mainly by the kidney and the liver and sequences required for tissue-specific expression have been localized in the Epo gene. A 3'enhancer is responsible for hypoxia-inducible Epo gene expression. HIF-1 alpha and beta proteins bind to this enhancer. Gene regulation by hypoxia is widespread in many cells and involves numerous genes in addition to the Epo gene. The Epo receptor belongs to the cytokine receptor family and includes a p66 chain which is dimerized upon Epo activation; two accessory proteins defined by cross-linking remain to be characterized. Epo binding induces the stimulation of Jak2 tyrosine kinase. Jak2 activation leads to the tyrosine phosphorylation of several proteins including the Epo receptor itself. As a result, different intracellular pathways are activated: Ras/MAP kinase, phosphatidylinositol 3-kinase and STAT transcription factors. However, the exact mechanisms by which the proliferation and/or the differentiation of erythroid cells are regulated after Epo stimulation are not known. Furthermore, target disruption of both Epo and Epo receptor showed that Epo was not involved in the commitment of the erythroid lineage and seemed to act mainly as a survival factor.

  14. Studies on Erythropoietin Bioassay Method

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Kyoung Sam; Ro, Heung Kyu; Lee, Mun Ho [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1975-09-15

    It is the purpose of this paper to design the most preferable method of erythropoietin bioassay in Korea. Bioassay utilizing polycythemic mice are currently in general use for the indirect determination of erythropoietin. Assay animals are usually prepared either by transfusion or by exposure to reduced oxygen tension in specially constructed chamber. We prepared the polycythemic mice by the specially constructed hypobaric chamber. We observed weights and hematocrits of the mice in the hypobaric chamber, then hematocrits and 72 hours {sup 59}Fe red cell uptake ratio of the polycythemic mice induced by hypoxia after removal from the hypobaric chamber. We designed the method of erythropoietin bioassay according to the results obtained by above experiments. Then we measured the 72 hours {sup 59}Fe red cell uptake ratio of the polycythemic mice with normal saline, normal plasma and anemic plasma according to the method we designed. The results are followed:1) The hematocrits of the mice in hypobaric chamber increased to 74% in 11 days. It is preferable to maintain the pressure of the chamber to 400 mmHg for first 4 days then 300 mmHg for last 10 days to reduce the death rate and time consuming in hypobaric chamber. 2) After removal from the hypobaric chamber, the 72 hours {sup 59}Fe red cell uptake ratio decreased rapidly and maintained the lowest level from the fourth day to tenth day. 3) We design the method of erythropoietin bioassay according to the results of above experiment and to the half life of erythropoietin. 4) The Korean product {sup 59}Fe is mixture of {sup 55}Fe and {sup 59}Fe. And the {sup 59}Fe red cell uptake ratio in normal mice was far less with Korean product {sup 59}Fe than with pure {sup 59}Fe of foreign product. So it is desirable to use pure {sup 59}Fe in this method of erythropoietin bioassay. 5) Considering the cost, the technique, the time consuming and the sensitivity it is the most preferable method of erythropoietin bioassay in Korea

  15. Erythropoietin: a multimodal neuroprotective agent

    OpenAIRE

    Byts, Nadiya; Sir?n, Anna-Leena

    2009-01-01

    Abstract The tissue protective functions of the hematopoietic growth factor erythropoietin (EPO) are independent of its action on erythropoiesis. EPO and its receptors (EPOR) are expressed in multiple brain cells during brain development and upregulated in the adult brain after injury. Peripherally administered EPO crosses the blood-brain barrier and activates in the brain anti-apoptotic, anti-oxidant and anti-inflammatory signaling in neurons, glial and cerebrovascular endothelial cells and ...

  16. Effect of carbamylated erythropoietin on retinopathy of diabetic rats

    Institute of Scientific and Technical Information of China (English)

    Lin Jiang

    2017-01-01

    Objective:To study the effect of carbamylated erythropoietin (CEPO) on retinopathy of diabetic rats.Methods: Male SD rats were selected as experimental animals and randomly divided into control group, DM group and CEPO group, and diabetic animal models were established and then given CEPO intervention. 2 weeks after intervention, the retina was collected to detect the expression of angiogenesis molecules, apoptosis molecules and oxidative stress pathway molecules.Results: HIF-1α, VEGF, Ang-1, Bax, Caspase-3, Nrf-2, ARE, HO-1 and NQO-1 mRNA expression in retina of DM group were significantly higher than those of control group while TKLK, PEDF, Bcl-2 and Survivin mRNA expression were significantly lower than those of control group; HIF-1α, VEGF, Ang-1, TKLK and PEDF mRNA expression in retina of CEPO group were not significantly different from those of DM group, Bcl-2, Survivin, Nrf-2, ARE, HO-1 and NQO-1 mRNA expression were significantly higher than those of DM group, and Bax and Caspase-3 mRNA expression were significantly lower than those of DM group.Conclusion:CEPO can reduce the apoptosis and oxidative stress injury of the retina tissue in diabetic rats without affecting the angiogenesis.

  17. Topical erythropoietin promotes wound repair in diabetic rats.

    Science.gov (United States)

    Hamed, Saher; Ullmann, Yehuda; Masoud, Muhannad; Hellou, Elias; Khamaysi, Ziad; Teot, Luc

    2010-01-01

    Wound healing in diabetic patients is slower than in healthy individuals. Erythropoietin (EPO) has non-hemopoietic targets in the skin, and systemically administered EPO promotes wound healing in experimental animals. This study investigated the effect of topical EPO treatment on defective wound repair in the skin of diabetic rats. Full-thickness excisional skin wounds were made in 38 rats, of which 30 had diabetes. The wounds were then treated topically with a cream that contained either vehicle, 600 IU ml(-1) EPO (low dose), or 3,000 IU ml(-1) (high dose) EPO. We assessed the rate of wound closure during the 12-day treatment period, and microvascular density (MVD), vascular endothelial growth factor (VEGF), and hydroxyproline (HP) contents, and the extent of apoptosis in wound tissues at the end of the 12-day treatment period. Topical EPO treatment significantly reduced the time to final wound closure. This increased rate of closure of the two EPO-treated wounds in diabetic rats was associated with increased MVD, VEGF, and HP contents, and a reduced extent of apoptosis. In light of our finding that topical EPO treatment promotes skin wound repair in diabetic rats, we propose that topical EPO treatment is a therapeutically beneficial method of treating chronic diabetic wounds.

  18. Recombinant human erythropoietin improves angiogenesis and wound healing in experimental burn wounds.

    Science.gov (United States)

    Galeano, Mariarosaria; Altavilla, Domenica; Bitto, Alessandra; Minutoli, Letteria; Calò, Margherita; Lo Cascio, Patrizia; Polito, Francesca; Giugliano, Giovanni; Squadrito, Giovanni; Mioni, Chiara; Giuliani, Daniela; Venuti, Francesco S; Squadrito, Francesco

    2006-04-01

    Erythropoietin interacts with vascular endothelial growth factor (VEGF) and stimulates endothelial cell mitosis and motility; thus it may be of importance in the complex phenomenon of wound healing. The purpose of this study was to investigate the effect of recombinant human erythropoietin (rHuEPO) on experimental burn wounds. Randomized experiment. Research laboratory. C57BL/6 male mice weighing 25-30 g. Mice were immersed in 80 degrees C water for 10 secs to achieve a deep-dermal second degree burn. Animals were randomized to receive either rHuEPO (400 units/kg/day for 14 days in 100 microL subcutaneously) or its vehicle alone (100 microl/day distilled water for 14 days subcutaneously). On day 14 the animals were killed. Burn areas were used for histologic examination, evaluation of neoangiogenesis by immunohistochemistry, and expression (Western blot) of the specific endothelial marker CD31 as well as quantification of microvessel density, measurement of VEGF wound content (enzyme-linked immunosorbent assay), expression (Western blot) of endothelial and inducible nitric oxide synthases, and determination of wound nitric oxide (NO) products. rHuEPO increased burn wound reepithelialization and reduced the time to final wound closure. These effects were completely abated by a passive immunization with specific antibodies against erythropoietin. rHuEPO improved healing of burn wound through increased epithelial proliferation, maturation of the extracellular matrix, and angiogenesis. The hematopoietic factor augmented neoangiogenesis as suggested by the marked increase in microvessel density and by the robust expression of the specific endothelial marker CD31. Furthermore, rHuEPO enhanced the wound content of VEGF caused a marked expression of endothelial and inducible nitric oxide synthases and increased wound content of nitric oxide products. Our study suggests that rHuEPO may be an effective therapeutic approach to improve clinical outcomes after thermal injury.

  19. 21 CFR 864.7250 - Erythropoietin assay.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Erythropoietin assay. 864.7250 Section 864.7250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7250 Erythropoietin...

  20. The Relationship of Erythropoietin Receptor Expression and ...

    African Journals Online (AJOL)

    2018-04-04

    Apr 4, 2018 ... brain tumor characterized with poor prognosis and short survival. In addition to the standard treatment protocols, targeted molecular treatment options are under trial. In the recent trials, erythropoietin and erythropoietin receptor were found to be linked with the progression of GBM cells. Aim: In this study, we.

  1. Recombinant human erythropoietin in sports: a review

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

  3. Anti-VEGF therapy in the management of retinopathy of prematurity: what we learn from representative animal models of oxygen-induced retinopathy

    Directory of Open Access Journals (Sweden)

    Wang H

    2016-05-01

    Full Text Available Haibo Wang Department of Ophthalmology, John A Moran Eye Center, The University of Utah, Salt Lake City, UT, USA Abstract: Retinopathy of prematurity (ROP remains a leading cause of childhood blindness, affecting infants born prematurely. ROP is characterized by the onset of delayed physiological retinal vascular development (PRVD and followed by pathologic neovascularization into the vitreous instead of the retina, called intravitreal neovascularization (IVNV. Therefore, the therapeutic strategy for treating ROP is to promote PRVD and inhibit or prevent IVNV. Vascular endothelial growth factor (VEGF plays an important role in the pathogenesis of ROP. There is a growing body of studies testing the use of anti-VEGF agents as a treatment for ROP. Intravitreal anti-VEGF treatment for ROP has potential advantages compared with laser photocoagulation, the gold standard for the treatment of severe ROP; however, intravitreal anti-VEGF treatment has been associated with reactivation of ROP and suppression of systemic VEGF that may affect body growth and organ development in preterm infants. Therefore, it is important to understand the role of VEGF in PRVD and IVNV. This review includes the current knowledge of anti-VEGF treatment for ROP from animal models of oxygen-induced retinopathy (OIR, highlighting the importance of VEGF inhibition by targeting retinal Müller cells, which inhibits IVNV and permits PRVD. The signaling events involved in mediating VEGF expression and promoting VEGF-mediated angiogenesis, including hypoxia-dependent signaling, erythropoietin/erythropoietin receptor-, oxidative stress-, beta-adrenergic receptor-, integrin-, Notch/Delta-like ligand 4- and exon guidance molecules-mediated signaling pathways, are also discussed. Keywords: vascular endothelial growth factor, retinopathy of prematurity, intravitreal neovascularization, oxygen-induced retinopathy model, physiological retinal vascular development

  4. Hepatic erythropoietin response in cirrhosis

    DEFF Research Database (Denmark)

    Risør, Louise M; Fenger, Mogens; Olsen, Niels Vidiendal

    2016-01-01

    The main function of erythropoietin (EPO) is to maintain red blood cell mass, but in recent years, increasing evidence has suggested a wider biological role not solely related to erythropoiesis, e.g. angiogenesis and tissue protection. EPO is produced in the liver during fetal life, but the main...... production shifts to the kidney after birth. The liver maintains a production capacity of up to 10% of the total EPO synthesis in healthy controls, but can be up-regulated to 90-100%. However, the hepatic EPO synthesis has been shown not to be adequate for correction of anemia in the absence of renal......, which lead to arterial hypotension, hepatic nephropathy and anemia. An increase in EPO due to renal hypoperfusion, hypoxia and anemia or an EPO-mediated hepato-protective and regenerative mechanism is plausible. However, poor hepatic synthesis capacity, a decreasing co-factor level and inflammatory...

  5. 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

  6. VEGF Signaling in Neurological Disorders

    Directory of Open Access Journals (Sweden)

    Joon W. Shim

    2018-01-01

    Full Text Available Vascular endothelial growth factor (VEGF is a potent growth factor playing diverse roles in vasculogenesis and angiogenesis. In the brain, VEGF mediates angiogenesis, neural migration and neuroprotection. As a permeability factor, excessive VEGF disrupts intracellular barriers, increases leakage of the choroid plexus endothelia, evokes edema, and activates the inflammatory pathway. Recently, we discovered that a heparin binding epidermal growth factor like growth factor (HB-EGF—a class of EGF receptor (EGFR family ligands—contributes to the development of hydrocephalus with subarachnoid hemorrhage through activation of VEGF signaling. The objective of this review is to entail a recent update on causes of death due to neurological disorders involving cerebrovascular and age-related neurological conditions and to understand the mechanism by which angiogenesis-dependent pathological events can be treated with VEGF antagonisms. The Global Burden of Disease study indicates that cancer and cardiovascular disease including ischemic and hemorrhagic stroke are two leading causes of death worldwide. The literature suggests that VEGF signaling in ischemic brains highlights the importance of concentration, timing, and alternate route of modulating VEGF signaling pathway. Molecular targets distinguishing two distinct pathways of VEGF signaling may provide novel therapies for the treatment of neurological disorders and for maintaining lower mortality due to these conditions.

  7. Impact of VEGF and VEGF receptor 1 (FLT1) expression on the prognosis of stage III esophageal cancer patients after radiochemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Rades, D. [Dept. of Radiation Oncology, Univ. Medical Center Hamburg-Eppendorf (Germany); Dept. of Radiation Oncology, Univ. Hospital Schleswig-Holstein, Luebeck (Germany); Golke, H. [Dept. of Radiation Oncology, Univ. Medical Center Hamburg-Eppendorf (Germany); Inst. of Pathology, Univ. Medical Center Hamburg-Eppendorf (Germany); Schild, S.E. [Dept. of Radiation Oncology, Mayo Clinic, Scottsdale, AZ (United States); Kilic, E. [Inst. of Pathology, Univ. Medical Center Hamburg-Eppendorf (Germany); Inst. of Pathology, Univ. Hospital Basel-Stadt (Switzerland)

    2008-08-15

    Background and purpose: high expression of vascular endothelial growth factor (VEGF) is negatively associated with clinical outcome. The prognostic value of VEGF receptor 1 (FLT1) is unclear. This retrospective study investigated the impact of tumor expression of VEGF and FLT1 on outcome in 68 stage III esophageal cancer patients. Material and methods: the impact of tumor VEGF and FLT expression (< 10% vs. > 10%) and five additional potential prognostic factors on overall survival (OS) and locoregional control (LC) was retrospectively evaluated. These factors included T-stage (T3 vs. T4), N-stage (NO vs. N1), treatment (radiochemotherapy plus resection vs. radiochemotherapy alone), erythropoietin (ERYPO {sup registered} 10000, Janssen-Cilag, Neuss, Germany) administration during radiotherapy, and majority of hemoglobin levels during radiotherapy (< 12 vs. {>=} 12 g/dl). Subgroup analyses were performed for patients receiving resection (R0 vs. R1/2 resection). The factors found to be significant on univariate analyses (Kaplan-Meier method, log-rank test) were included in multivariate analyses performed with the Cox proportional hazard model. Results: on univariate analysis, improved OS was associated with T3 stage (p = 0.011), surgery (p = 0.019), and hemoglobin {>=} 12 g/dl (p < 0.001). Improved LC was associated with T3 stage (p = 0.025), hemoglobin {>=} 12 g/dl (p < 0.001), and VEGF negativity (p = 0.045). On multivariate analyses, only hemoglobin maintained significance. In patients having surgery, R0 resection was significantly better than R1/2 resection for OS (p < 0.001) and LC (p < 0.001). Conclusion: preradiotherapy tumor VEGF expression appears negatively correlated with outcomes, whereas FLT1 expression appears to have no significant impact on OS and LC. (orig.)

  8. Impact of VEGF and VEGF receptor 1 (FLT1) expression on the prognosis of stage III esophageal cancer patients after radiochemotherapy

    International Nuclear Information System (INIS)

    Rades, D.; Golke, H.; Schild, S.E.; Kilic, E.

    2008-01-01

    Background and purpose: high expression of vascular endothelial growth factor (VEGF) is negatively associated with clinical outcome. The prognostic value of VEGF receptor 1 (FLT1) is unclear. This retrospective study investigated the impact of tumor expression of VEGF and FLT1 on outcome in 68 stage III esophageal cancer patients. Material and methods: the impact of tumor VEGF and FLT expression ( 10%) and five additional potential prognostic factors on overall survival (OS) and locoregional control (LC) was retrospectively evaluated. These factors included T-stage (T3 vs. T4), N-stage (NO vs. N1), treatment (radiochemotherapy plus resection vs. radiochemotherapy alone), erythropoietin (ERYPO registered 10000, Janssen-Cilag, Neuss, Germany) administration during radiotherapy, and majority of hemoglobin levels during radiotherapy (< 12 vs. ≥ 12 g/dl). Subgroup analyses were performed for patients receiving resection (R0 vs. R1/2 resection). The factors found to be significant on univariate analyses (Kaplan-Meier method, log-rank test) were included in multivariate analyses performed with the Cox proportional hazard model. Results: on univariate analysis, improved OS was associated with T3 stage (p = 0.011), surgery (p = 0.019), and hemoglobin ≥ 12 g/dl (p < 0.001). Improved LC was associated with T3 stage (p = 0.025), hemoglobin ≥ 12 g/dl (p < 0.001), and VEGF negativity (p = 0.045). On multivariate analyses, only hemoglobin maintained significance. In patients having surgery, R0 resection was significantly better than R1/2 resection for OS (p < 0.001) and LC (p < 0.001). Conclusion: preradiotherapy tumor VEGF expression appears negatively correlated with outcomes, whereas FLT1 expression appears to have no significant impact on OS and LC. (orig.)

  9. Erythropoietin in Cardiorenal Anemia Syndrome

    Directory of Open Access Journals (Sweden)

    Emir Fazlibegović

    2008-11-01

    Full Text Available Incidents of heart and renal failure (HF, RF together, are increasing in our country and all over the world, so a great attention has been dedicated to this problem recently. These diseases together have shown bad results because of the process of accelerated arteriosclerosis, structural changes of myocardium, oxidative stress, inflammation, increased activities of sympathetic nervous system (SNS, increased activities of a renin-angiotensin-aldosterone system (RAAS. These factors are crucial in the development of patho-physiological process and consequential development of anemia, that together with heart and renal failure through interaction, cause serious disorder that we call the cardio-renal anemia syndrome. We examined effects of erythropoietin (Epoetin beta at 90 (60 men and 30 women pre-dialysed and dialysed patients with HF signs during a period of three years in individual dozes of 2000-6000 units subcutaneous (sc weekly. Using computer S PLUS and SAS multiple variant analysis we have got correlations by Pearson. Epoetin beta significantly develops anemiaparameters: number of erythrocytes (r=0.51779; p<0.0001, hemoglobin (r=0.38811; p<0.0002, MCV (r=0.59876; p<0.0001 at patients with HF. Positive effects are seen at NYHA class (r=0.59906; p<0.0001, on quality of life before and after prescribing medicine. Parameters of renal functions are improving: more urea (r =0.45557; p<0.0001 than creatinine (r=0.26397; p<0.00119 and potassium values K(+ are not changed significantly (r=0.02060; p<0.8471. Epoetin beta has been useful in treatment of pre-dialysed and dialysed patients with HF and anemia by improving functional ability of myocardium and quality of life.

  10. Therapeutic implications of recombinant human erythropoietin in ...

    African Journals Online (AJOL)

    AJB SERVER

    2006-12-29

    Dec 29, 2006 ... quence of both, RHUEPO has achieved the highest annual sales ... analysis of the US Medicare database (Ma et al., 1999) ... blood transfusions and improves quality of life (Eschbach, ... Large doses of EPO results increase in blood pressure .... human erythropoietin was obtained from human genomic.

  11. Erythropoietin: ready for prime-time cardioprotection.

    NARCIS (Netherlands)

    Riksen, N.P.; Hausenloy, D.J.; Yellon, D.

    2008-01-01

    To improve clinical outcomes in patients presenting with an acute myocardial infarction, new strategies to limit infarct size and postinfarct remodelling are warranted. Recent animal studies have revealed that erythropoietin has the potential to achieve both these goals. Even more intriguing is the

  12. Erythropoietin receptor signaling is membrane raft dependent

    NARCIS (Netherlands)

    K.L. McGraw (Kathy); G.M. Fuhler (Gwenny); J.O. Johnson (Joseph); J.A. Clark (Justine); G.C. Caceres (Gisela); L. Sokol (Lubomir); A.F. List (Alan)

    2012-01-01

    textabstractUpon erythropoietin (Epo) engagement, Epo-receptor (R) homodimerizes to activate JAK2 and Lyn, which phosphorylate STAT5. Although recent investigations have identified key negative regulators of Epo-R signaling, little is known about the role of membrane localization in controlling

  13. Does erythropoietin augment noise induced hearing loss?

    DEFF Research Database (Denmark)

    Frederiksen, Birgitte Lidegaard; Cayé-Thomasen, Per; Lund, Søren Peter

    2007-01-01

    Noise-induced hearing loss may result from excessive release of glutamate, nitrogen oxide and reactive oxygen species. The effects of these factors on the inner ear may potentially be prevented or reduced by erythropoietin (EPO), as indicated by previously demonstrated neuro-protective effects of...

  14. Enhancement of gene expression under hypoxic conditions using fragments of the human vascular endothelial growth factor and the erythropoietin genes

    International Nuclear Information System (INIS)

    Shibata, Toru; Akiyama, Nobutake; Noda, Makoto; Sasai, Keisuke; Hiraoka, Masahiro

    1998-01-01

    Purpose: Selective gene expression in response to tumor hypoxia may provide new avenues, not only for radiotherapy and chemotherapy, but also for gene therapy. In this study, we have assessed the extent of hypoxia responsiveness of various DNA constructs by the luciferase assay to help design vectors suitable for cancer therapy. Materials and Methods: Reporter plasmids were constructed with fragments of the human vascular endothelial growth factor (VEGF) and the erythropoietin (Epo) genes encompassing the putative hypoxia-responsive elements (HRE) and the pGL3 promoter vector. Test plasmids and the control pRL-CMV plasmid were cotransfected into tumor cells by the calcium phosphate method. After 6 h hypoxic treatment, the reporter assay was performed. Results: The construct pGL3/VEGF containing the 385 bp fragment of the 5' flanking region in human VEGF gene showed significant increases in luciferase activity in response to hypoxia. The hypoxic/aerobic ratios were about 3-4, and 8-12 for murine and human tumor cells, respectively. Despite the very high degree of conservation among the HREs of mammalian VEGF genes, murine cells showed lower responsiveness than human cells. We next tested the construct pGL3/Epo containing the 150 bp fragment of the 3' flanking region in the Epo gene. Luciferase activity of pGL3/Epo was increased with hypoxia only in human cell lines. The insertion of 5 copies of the 35-bp fragments derived from the VEGF HREs and 32 bp of the E1b minimal promoter resulted in maximal enhancement of hypoxia responsiveness. Conclusions: The constructs with VEGF or Epo fragments containing HRE may be useful for inducing specific gene expression in hypoxic cells. Especially, the application of multiple copies of the HREs and an E1b minimal promoter appears to have the advantage of great improvement in hypoxia responsiveness

  15. Recombinant human erythropoietin stimulates angiogenesis and wound healing in the genetically diabetic mouse.

    Science.gov (United States)

    Galeano, Mariarosaria; Altavilla, Domenica; Cucinotta, Domenico; Russo, Giuseppina T; Calò, Margherita; Bitto, Alessandra; Marini, Herbert; Marini, Rolando; Adamo, Elena B; Seminara, Paolo; Minutoli, Letteria; Torre, Valerio; Squadrito, Francesco

    2004-09-01

    The effects of recombinant human erythropoietin (rHuEPO) in diabetes-related healing defects were investigated by using an incisional skin-wound model produced on the back of female diabetic C57BL/KsJ-m(+/+)Lept(db) mice (db(+)/db(+)) and their normoglycemic littermates (db(+/+)m). Animals were treated with rHuEPO (400 units/kg in 100 microl s.c.) or its vehicle alone (100 microl). Mice were killed on different days (3, 6, and 12 days after skin injury) for measurement of vascular endothelial growth factor (VEGF) mRNA expression and protein synthesis, for monitoring angiogenesis by CD31 expression, and for evaluating histological changes. Furthermore, we evaluated wound-breaking strength at day 12. At day 6, rHuEPO injection in diabetic mice resulted in an increase in VEGF mRNA expression (vehicle = 0.33 +/- 0.1 relative amount of mRNA; rHuEPO = 0.9 +/- 0.09 relative amount of mRNA; P < 0.05) and protein wound content (vehicle = 23 +/- 5 pg/wound; rHuEPO = 92 +/- 12 pg/wound; P < 0.05) and caused a marked increase in CD31 gene expression (vehicle = 0.18 +/- 0.05 relative amount of mRNA; rHuEPO = 0.98 +/- 0.21 relative amount of mRNA; P < 0.05) and protein synthesis. Furthermore, rHuEPO injection improved the impaired wound healing and, at day 12, increased the wound-breaking strength in diabetic mice (vehicle = 12 +/- 2 g/mm; rHuEPO 21 +/- 5 g/mm; P < 0.05). Erythropoietin may have a potential application in diabetes-related wound disorders.

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

    Directory of Open Access Journals (Sweden)

    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  

  17. Polycythemia in transgenic mice expressing the human erythropoietin gene

    International Nuclear Information System (INIS)

    Semenza, G.L.; Traystman, M.D.; Gearhart, J.D.; Antonarakis, S.E.

    1989-01-01

    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' flanking sequence and 0.7 kilobase of 3' 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

  18. Serum level of vascular endothelial growth factor is influenced by erythropoietin treatment in peritoneal dialysis patients. (Grupo de Estudios Peritoneales de Madrid).

    Science.gov (United States)

    del Peso, G; Selgas, R; Bajo, M A; Fernández de Castro, M; Aguilera, A; Cirugeda, A; Jiménez, C

    2000-01-01

    Some patients on long-term peritoneal dialysis (PD) develop a hyperpermeability state, owing to peritoneal neoangiogenesis. Vascular endothelial growth factor (VEGF), a potent mitogen for endothelial cells, has been implicated in most diseases characterized by microvascular neoformation. Erythropoietin (EPO) is able to induce endothelial proliferation in vitro. Our aim was to elucidate whether VEGF serum levels are influenced by EPO treatment, and whether VEGF serum level maintains a relationship with peritoneal transport data. We analyzed serum levels of VEGF in 35 PD patients (18 males, 17 females). Mean age was 58 years, with a mean time on PD of 98 +/- 75 months. Of the 35 patients, 19 were on automated peritoneal dialysis, and 16 were on continuous ambulatory peritoneal dialysis. Seven patients had diabetes. Peritoneal transport parameters were: urea mass transfer coefficient (MTC), 19.5 +/- 6.6 mL/min; creatinine MTC, 9.9 +/- 4.7 mL/min; net ultrafiltration, 491 +/- 166 mL per 4-hour dwell. Twenty seven patients were under therapy with recombinant human erythropoietin (rHuEPO). Mean serum VEGF levels were 347 +/- 203 pg/mL (range 66-857 pg/mL), with most patients in the normal range (60-700 pg/mL). VEGF levels did not correlate with age, sex, primary renal disease, diabetes, type of PD, time on PD, peritonitis, and cumulative glucose load. We found no correlation with urea MTC, creatinine MTC, ultrafiltration rate, or protein effluent levels. However, a significant negative correlation with residual renal function was seen (r = -0.39, p < 0.05). Patients treated with rHuEPO showed significantly higher serum levels of VEGF than non treated patients (375 +/- 220 pg/mL vs 251 +/- 75 pg/mL, p < 0.05), although they had similar residual renal function. We conclude that increased serum VEGF levels are associated with EPO treatment. Consequently, VEGF might have a role in the EPO effects found in PD patients. Whether both agents are related to peritoneal

  19. Anti-VEGF drugs: evidence for effectiveness

    OpenAIRE

    Evans, Jennifer; Virgili, Gianni

    2014-01-01

    Anti-vascular endothelial growth factors (anti-VEGF) are targeted biological drugs (e.g. monoclonal antibodies) that prevent the growth of new vessels by inhibiting VEGF. VEGF is a cytokine (cell-signalling protein) that promotes the growth of, and leakage from, new vessels. Currently there are three anti-VEGF drugs licensed for use in eye disease: pegaptanib, aflibercept, ranibizumab and one that is not licensed but is commonly used off-label (bevacizumab).

  20. Erythropoietin improves the survival of fat tissue after its transplantation in nude mice.

    Directory of Open Access Journals (Sweden)

    Saher Hamed

    Full Text Available BACKGROUND: Autologous transplanted fat has a high resorption rate, providing a clinical challenge for the means to reduce it. Erythropoietin (EPO has non-hematopoietic targets, and we hypothesized that EPO may improve long-term fat graft survival because it has both pro-angiogenic and anti-apoptotic properties. We aimed to determine the effect of EPO on the survival of human fat tissue after its transplantation in nude mice. METHODOLOGY/PRINCIPAL FINDINGS: Human fat tissue was injected subcutaneously into immunologically-compromised nude mice, and the grafts were then treated with either 20 IU or 100 IU EPO. At the end of the 15-week study period, the extent of angiogenesis, apoptosis, and histology were assessed in the fat grafts. The results were compared to vascular endothelial growth factor (VEGF-treated and phosphate-buffered saline (PBS-treated fat grafts. The weight and volume of the EPO-treated grafts were higher than those of the PBS-treated grafts, whose weights and volumes were not different from those of the VEGF-treated grafts. EPO treatment also increased the expression of angiogenic factors and microvascular density, and reduced inflammation and apoptosis in a dose-dependent manner in the fat grafts. CONCLUSIONS/SIGNIFICANCE: Our data suggest that stimulation of angiogenesis by a cluster of angiogenic factors and decreased fat cell apoptosis account for potential mechanisms that underlie the improved long-term survival of fat transplants following EPO treatment.

  1. Erythropoietin improves the survival of fat tissue after its transplantation in nude mice.

    Science.gov (United States)

    Hamed, Saher; Egozi, Dana; Kruchevsky, Danny; Teot, Luc; Gilhar, Amos; Ullmann, Yehuda

    2010-11-15

    Autologous transplanted fat has a high resorption rate, providing a clinical challenge for the means to reduce it. Erythropoietin (EPO) has non-hematopoietic targets, and we hypothesized that EPO may improve long-term fat graft survival because it has both pro-angiogenic and anti-apoptotic properties. We aimed to determine the effect of EPO on the survival of human fat tissue after its transplantation in nude mice. Human fat tissue was injected subcutaneously into immunologically-compromised nude mice, and the grafts were then treated with either 20 IU or 100 IU EPO. At the end of the 15-week study period, the extent of angiogenesis, apoptosis, and histology were assessed in the fat grafts. The results were compared to vascular endothelial growth factor (VEGF)-treated and phosphate-buffered saline (PBS)-treated fat grafts. The weight and volume of the EPO-treated grafts were higher than those of the PBS-treated grafts, whose weights and volumes were not different from those of the VEGF-treated grafts. EPO treatment also increased the expression of angiogenic factors and microvascular density, and reduced inflammation and apoptosis in a dose-dependent manner in the fat grafts. Our data suggest that stimulation of angiogenesis by a cluster of angiogenic factors and decreased fat cell apoptosis account for potential mechanisms that underlie the improved long-term survival of fat transplants following EPO treatment.

  2. Vascular endothelial growth factor ( VEGF ) receptor expression ...

    African Journals Online (AJOL)

    Avidin-biotin complex method was employed for immunohistochemical detection of VEGF. Results: VEGF immuno-expression was positive in 51.9% of CRC, while it was 18.2% in the normal colonic tissue (p<0.05). VEGF immunostaining was positively correlated with grade of colonic malignancy (p<0.05). Conclusion: ...

  3. Accuracy of erythropoietin determination in the dialysate of CAPD patients

    NARCIS (Netherlands)

    Struijk, D. G.; Koomen, G. C.; Krediet, R. T.; Arisz, L.

    1990-01-01

    In vitro experiments were performed to analyze problems with the determination of erythropoietin in dialysate. Human recombinant erythropoietin (EPO; 4000 U/L) was added to several fluids, to glass or polystyrene tubes with or without addition of bovine serum albumin (BSA) and to dialysate bags. The

  4. Hypoxia and the initiation of erythropoietin production. [Rats

    Energy Technology Data Exchange (ETDEWEB)

    Schooley, J.C.; Mahlmann, L.J.

    1975-01-01

    The initiation of erythropoietin production in rats by hypoxia is dependent upon the magnitude of the hypoxic exposure, the position of the oxygen dissociation curve at the time of the hypoxic exposure, and the animal's endocrine status. Normal male rats produce more erythropoietin and elevate their intraerythrocytic 2,3-DPG levels more than female rats exposed to the same degree of hypoxia. Hypophysectomized rats produce erythropoietin following severe hypoxic exposure, but do not elevate their 2,3-DPG levels above control values. Respiratory acidosis in rats produced by breathing 10 percent CO/sub 2/ or by the injection of acetazolamide inhibits the initiation of erythropoietin production by hypoxic environments, but this inhibition is minimal in animals with metabolic acidosis produced by ureterligation. Changes in serum erythropoietin levels and the in vitro P/sub 50/ appear to be two separate but interrelated physiological events which occur during the adaptation of animals to hypoxic environments.

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

    Science.gov (United States)

    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.

  6. Erythropoiesis and erythropoietin in hypo- and hyperthyroidism.

    Science.gov (United States)

    Das, K C; Mukherjee, M; Sarkar, T K; Dash, R J; Rastogi, G K

    1975-02-01

    Qualitative and quantitative studies of erythropoiesis in 23 patients with hypothyroidism and 21 patients with hyperthryoidism included routine hematologic evaluation, bone marrow morphology, status of serum iron, B12 and folate red blood cell mass and plasma volume by radioisotope methods, erythrokinetics and radiobioassay of plasma erythropoietin. A majority of patients with the hypothyroid state had significant reduction in red blood cell mas per kg of body weight. The presence of anemia in many of these patients was not evident from hemoglobin and hematocrit values due to concomitant reduction of plasma volume. The erythrokinetic data in hypothyroid patients provided evidence of significant decline of the erythropoietic activity of the bone marrow. Erythroid cells in the marrow were depleted and also showed reduced proliferative activity as indicated by lower 3H-thymidine labeling index. Plasma erythropoietin levels were reduced, often being immeasurable by the polycythemic mouse bioassay technique. These changes in erythropoiesis in the hypothyroid state appear to be a part of physiological adjustment to the reduced oxygen requirement of the tissues due to diminished basal metabolic rate. Similar investigations revealed mild erythrocytosis in a significant proportion of patients with hyperthyroidism. Failure of erythrocytosis to occur in other patients of this group was associated with impaired erythropoiesis due to a deficiency of hemopoietic nutrients such as iron, vitamin B12 and folate. The mean plasma erythropoietin level of these patients was significantly elevated; in 4 patients the levels were in the upper normal range whereas in the rest, the values were above the normal range. The bone marrow showed erythyroid hyperplasia in all patients with hyperthyroidism. The mean 3H-thymidine labeling index of the erythroblasts was also significantly higher than normal in hyperthyroidism; in 8 patients the index was within the normal range whereas in the

  7. Autosomal dominant familial erythrocytosis due to autonomous erythropoietin production

    International Nuclear Information System (INIS)

    Distelhorst, C.W.; Wagner, D.S.; Goldwasser, E.; Adamson, J.W.

    1981-01-01

    A family is described in which four members spanning three consecutive generations have erythrocytosis associated with a normal hemoglobin oxygen affinity. When bone marrow from one affected family member was cultured in vitro, erythroid colonies formed only when erythropoietin was added to the culture. Serum erythropoietin, measured by radioimmunoassay, was significantly elevated above normal in each of the affected family members. Bioassayable erythropoietin was detected in the urine of two of the three affected family members. In two of the affected family members, erythropoietin was measured in serum by radioimmunoassay and in urine by bioassay before and for 4 days following an isovolemic phlebotomy, which reduced the red cell mass by 20%. Neither serum nor urinary erythropoietin levels changed following phlebotomy. The erythrocytosis in this family appears to be secondary to inappropriately increased erythropoietin production unassociated with a decrease in the blood oxygen-carrying capacity. This is the first instance in which autonomous erythropoietin production appears to be inherited on an autosomal dominant basis

  8. Erythropoietin in stroke therapy: friend or foe.

    Science.gov (United States)

    Souvenir, Rhonda; Doycheva, Desislava; Zhang, John H; Tang, Jiping

    2015-01-01

    Recombinant human erythropoietin (rhEPO), over the past decade, was hailed as an auspicious therapeutic strategy for various types of brain injuries. The promising results from experiments conducted in animal models of stroke led to a hurried clinical trial that was swiftly aborted in Phase II. The multiple neuroprotective modalities of rhEPO failed to translate smoothly to human adult ischemic brain injury and provided limited aid to neonates. In light of the antithetical results, several questions were raised as to why and how this clinical trial failed. There was bolstering evidence from the preliminary studies that pointed to a bright future. Therefore, the objective of this review is to address these questions by discussing the signaling pathways of rhEPO that are reported to mediate the neuroprotective effect in various animal models of brain injury. Major biomedical bibliographical databases (MEDLINE, ISI, PubMed, and Cochrane Library) were searched with the use of keywords such as erythropoietin, stroke, neonatal hypoxia ischemia, intracerebral hemorrhage, etc. This article will discuss the confounding factors that influence the efficacy of rhEPO treatment hence challenging its clinical translatability. Lastly, rhEPO may still be a promising therapeutic candidate for neonates in spite of its shortcoming in clinical trial if caution is taken with the dose and duration of its administration.

  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. The Impact of Tumor Expression of Erythropoietin Receptors and Erythropoietin on Clinical Outcome of Esophageal Cancer Patients Treated With Chemoradiation

    International Nuclear Information System (INIS)

    Rades, Dirk; Golke, Helmut; Schild, Steven E.; Kilic, Ergin

    2008-01-01

    Background: To investigate the impact of tumor erythropoietin receptors (Epo-R) and erythropoietin (Epo) expression in 64 patients with Stage III esophageal cancer receiving or not receiving erythropoietin during chemoradiation. Materials and Methods: The impact of tumor Epo-R expression, Epo expression, and 10 additional factors (age, Karnofsky-Performance-Score [KPS], tumor length, T and N stage, histology and grading, hemoglobin during radiotherapy, erythropoietin administration, surgery) on overall survival (OS) and locoregional control (LC) was evaluated. Results: Improved OS was associated with low (≤20%) Epo expression (p = 0.049), KPS >80 (p 0.008), T3 stage (p = 0.010), hemoglobin ≥12 g/dL (p < 0.001), and surgery (p = 0.010). Erythropoietin receptor expression showed a trend (p = 0.09). Locoregional control was associated with T stage (p = 0.005) and hemoglobin (p < 0.001), almost with erythropoietin administration (p = 0.06). On multivariate analyses, OS was associated with KPS (p = 0.045) and hemoglobin (p = 0.032), LC with hemoglobin (p < 0.001). Patients having low expression of both Epo-R and Epo had better OS (p = 0.003) and LC (p = 0.043) than others. Two-year OS was nonsignificantly better (p = 0.25) in patients with low Epo-R expression receiving erythropoietin (50%) than in those with higher Epo-R expression receiving erythropoietin (21%), low Epo-R expression/no erythropoietin administration (29%), or higher Epo-R expression/no erythropoietin administration (18%). Two-year LC rates were, respectively, 65%, 31%, 26%, and 29% (p = 0.20). Results for Epo expression were similar. Conclusions: Higher Epo-R expression or Epo expression seemed to be associated with poorer outcomes. Patients with low expression levels receiving erythropoietin seemed to do better than patients with higher expression levels or not receiving erythropoietin. The data need to be confirmed in a larger series of patients

  11. Fetal plasma erythropoietin concentration in severe growth retardation.

    Science.gov (United States)

    Snijders, R J; Abbas, A; Melby, O; Ireland, R M; Nicolaides, K H

    1993-02-01

    The aim of this study was to determine whether hypoxemia induces an increase in plasma erythropoietin concentration in human fetal life and, if so, whether this response stimulates fetal erythropoiesis. The plasma erythropoietin concentration in blood samples from 33 small-for-gestational-age fetuses at 26 to 38 weeks' gestation was measured. Measurements were compared with the reference range for gestation, and associations with PO2, pH, and erythroblast and erythrocyte counts were examined. The mean plasma erythropoietin concentration in the small-for-gestational-age fetuses was significantly increased, and the degree of increase was significantly associated both with fetal acidemia and, more strongly, with fetal erythroblastosis. Erythropoietin production in response to tissue hypoxia occurs from at least 26 weeks' gestation with measurable physiologic effects on erythropoiesis. Furthermore, more accurate assessment of tissue oxygenation may be obtained by measuring the erythroblast count rather than the blood pH.

  12. VEGF immunoexpression in penile carcinoma

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Pereira Martins

    2002-01-01

    Full Text Available OBJECTIVE: To investigate the vessel endothelial growth factor (VEGF as a risk factor in squamous cell carcinoma of the penis (SCCP. METHODS: Forty-seven patients with penile carcinoma were evaluated retrospectively. The mean age and standard deviation were 61.1±11.7 years. All of them were treated by penectomy and those with positive nodes underwent groin lymphadenectomy. Tumor grading was 35 G1 and 12 G2/3. Primary lesion stage was 24 pT1 and 23 pT2-4. Positive inguinal nodes were observed in 15 patients. Selected paraffin embedded sections were submitted to VEGF immunohistochemical analysis by the avidin-biotin-immunoperoxidase method with antigen retrieval. All slides were examined using an automatic analyzer system and the proportion of labeled cells in 10 high magnification power fields (400X were recorded in a blind analysis. RESULTS: Median (% labeling index was 2.3 in G1 versus 2.2 in G2/3 tumors (p=0.60, and 4.0 in pT1 versus 1.8 pT2-4 tumors (p=0.10. The respective data for pN0 patients was 2.8 and for pN+ was 2.1 (p=0.20. Survival curves showed no association with patients survival. CONCLUSION: In squamous cell carcinoma of the penis the VEGF immunoexpression has no association with tumor grade or stage, as well as with patient survival.

  13. High-dose erythropoietin for tissue protection

    DEFF Research Database (Denmark)

    Lund, Anton; Lundby, Carsten; Olsen, Niels Vidiendal

    2014-01-01

    BACKGROUND: The discovery of potential anti-apoptotic and cytoprotective effects of recombinant human erythropoietin (rHuEPO) has led to clinical trials investigating the use of high-dose, short-term rHuEPO therapy for tissue protection in conditions such as stroke and myocardial infarction....... Experimental studies have been favourable, but the clinical efficacy has yet to be validated. MATERIALS AND METHODS: We have reviewed clinical studies regarding the use of high-dose, short-term rHuEPO therapy for tissue protection in humans with the purpose to detail the safety and efficacy of r...... no effect of rHuEPO therapy on measures of tissue protection. Five trials including 1025 patients reported safety concerns in the form of increased mortality or adverse event rates. No studies reported reduced mortality. CONCLUSIONS: Evidence is sparse to support a tissue-protective benefit of r...

  14. Synthesis and structure of ternary lithium, calcium, copper phosphate Ca9CuLi(PO4)7

    International Nuclear Information System (INIS)

    Yanov, O.V.; Morozov, V.A.; Koznyakov, I.V.; Lazoryak, B.I.; Khasanov, S.S.

    1998-01-01

    New Ca 9 CuLi(PO 4 ) 7 compound is synthesized and specified through the methods of roentgenographic and thermogravimetric analysis. This compound is crystallized in trigonal syngony (sp.gr. R3c, Z=6) and is related to the structural type of the vitlokite natural mineral. The crystal structure (a=10.3231(2), c=37.111(1)A, V=3425(2)A 3 , R WP =5.99, R p =4/35, R I =2.25, R F =1.11, R E =3.28) is verified through the Ritweld method. The calcium cations are positioned in three nonequivalent octaapexed. The copper cations are located in a distorted octahedron. The lithium cations occupy irregularly and statistically two types of positions Li(A) (75(6)%) and Li(B) (25(6)%)uLi(PO 4 ) 7

  15. 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.

  16. 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.

  17. VEGF regulates TRPC6 channels in podocytes

    DEFF Research Database (Denmark)

    Thilo, Florian; Liu, Ying; Loddenkemper, Christoph

    2012-01-01

    increased TRPC6 mRNA expression and TRPC6 protein levels. The effects of VEGF165 were dose dependent and could be blocked by phosphoinositide-3-kinase inhibitors. In the presence of cycloheximide, an inhibitor of protein biosynthesis, we did not observe an effect of VEGF on TRPC6 protein levels, indicating...

  18. 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.

  19. Cervical spinal erythropoietin induces phrenic motor facilitation via ERK and Akt signaling

    Science.gov (United States)

    Dale, Erica A.; Satriotomo, Irawan; Mitchell, Gordon S.

    2012-01-01

    Erythropoietin (EPO) is typically known for its role in erythropoiesis, but is also a potent neurotrophic/neuroprotective factor for spinal motor neurons. Another trophic factor regulated by Hypoxia-Inducible Factor-1, vascular endothelial growth factor (VEGF), signals via ERK and Akt activation to elicit long-lasting phrenic motor facilitation (pMF). Since EPO also signals via ERK and Akt activation, we tested the hypothesis that EPO elicits similar pMF. Using retrograde labeling and immunohistochemical techniques, we demonstrate in adult, male, Sprague-Dawley rats that EPO and its receptor, EPO-R, are expressed in identified phrenic motor neurons. Intrathecal EPO at C4 elicits long-lasting pMF; integrated phrenic nerve burst amplitude increased >90 min post-injection (63±12% baseline 90 min post-injection; pphrenic motor neurons; EPO also increased pAkt (1.6 fold vs controls; pphrenic motor neurons (p<0.05), indicating a complex interaction between these kinases. We conclude that EPO elicits spinal plasticity in respiratory motor control. Since EPO expression is hypoxia-sensitive, it may play a role in respiratory plasticity in conditions of prolonged or recurrent low oxygen. PMID:22539857

  20. Studying of the standardization principles of pharmacological activity of recombinant erythropoietin preparations

    OpenAIRE

    A. K. Yakovlev; L. A. Gayderova; N. A. Alpatova; T. N. Lobanova; E. L. Postnova; E. I. Yurchikova; T. A. Batuashvili; R. A. Volkova; V. N. Podkuiko; Yu. V. Olefir

    2016-01-01

    Analysis of the publications devoted to the structure, functions, mechanism of action of erythropoietin is given in the article. Erythropoietin preparations derived from recombinant DNA technology are a mixture of isoforms with different biological activity, which determine the biological properties pharmacological activity, pharmacokinetics, efficacy and safety of medicinal product. Erythropoietin preparations derived by using recombinant DNA technology are a mixture of isoforms with differe...

  1. Crystal structures of double vanadates Ca9R(VO4)7. 1. R = La, Pr and Eu

    International Nuclear Information System (INIS)

    Belik, A.A.; Morozov, V.A.; Lazoryak, B.I.; Khasanov, S.S.

    1997-01-01

    Crystalline structures of Ca 9 R(VO 4 ) 7 (R = La(1), Pr(2), Eu(3)) were studied by means of the complete profile analysis. The compounds crystallize in trigonal syngony (sp.gr. R3c, Z=6) with the following parameters of the elementary cells: 1 - a=10.8987(5), c = 38.147(1) A, V = 3924.1(3) A; 2 - a 10.8808(7), c = 38.135(1) A, V = 3910.0(3) A; 3 - a = 10.8651(1), c 38.089(1) A, V = 3894.0(3) A 3 . The rare-earth element cations together with calcium population density of the rare-earth element cations in the positions changes regularly depending on their radius. In some compounds starting from La up to Eu the population density of the rare-earth element cations in M(3) position decreases, while that in M(1) and M(2) position - increases

  2. Erythropoietin Receptor Signaling Is Membrane Raft Dependent

    Science.gov (United States)

    McGraw, Kathy L.; Fuhler, Gwenny M.; Johnson, Joseph O.; Clark, Justine A.; Caceres, Gisela C.; Sokol, Lubomir; List, Alan F.

    2012-01-01

    Upon erythropoietin (Epo) engagement, Epo-receptor (R) homodimerizes to activate JAK2 and Lyn, which phosphorylate STAT5. Although recent investigations have identified key negative regulators of Epo-R signaling, little is known about the role of membrane localization in controlling receptor signal fidelity. Here we show a critical role for membrane raft (MR) microdomains in creation of discrete signaling platforms essential for Epo-R signaling. Treatment of UT7 cells with Epo induced MR assembly and coalescence. Confocal microscopy showed that raft aggregates significantly increased after Epo stimulation (mean, 4.3±1.4(SE) vs. 25.6±3.2 aggregates/cell; p≤0.001), accompanied by a >3-fold increase in cluster size (p≤0.001). Raft fraction immunoblotting showed Epo-R translocation to MR after Epo stimulation and was confirmed by fluorescence microscopy in Epo stimulated UT7 cells and primary erythroid bursts. Receptor recruitment into MR was accompanied by incorporation of JAK2, Lyn, and STAT5 and their activated forms. Raft disruption by cholesterol depletion extinguished Epo induced Jak2, STAT5, Akt and MAPK phosphorylation in UT7 cells and erythroid progenitors. Furthermore, inhibition of the Rho GTPases Rac1 or RhoA blocked receptor recruitment into raft fractions, indicating a role for these GTPases in receptor trafficking. These data establish a critical role for MR in recruitment and assembly of Epo-R and signal intermediates into discrete membrane signaling units. PMID:22509308

  3. Serum erythropoietin levels by radioimmunoassay in polycythaemia

    Energy Technology Data Exchange (ETDEWEB)

    Birgegaard, G.; Miller, O.; Caro, J.; Erslev, A. (Cardeza Foundation for Hematological Research, Jefferson University, Philadelphia, Pa.)

    1982-01-01

    A radioimmunoassay (RIA) method for erythropoietin (Epo) was developed and validated against the polycythaemic mouse assay. The correlation was good, with a r=0.94. Several other criteria of specificity were also filled by the RIA, which had a lower detection limit of 5 mU/ml. The mean serum-Epo level in 6 patients with secondary polycythaemia, 50.2 +- 26.2 mU/ml, was significantly higher than in a group of 11 normal subjects, 28.7 +- 7.2 mU/ml (P<0.0002). However, the Epo level in 31 polycythaemia vera (PV) patients, M = 21.9 +- 6.6 mU/ml, was not significantly different from normal (P = 0.006). Since previous studies with bioassay of heat-treated and concentrated plasma samples have shown a decreased serum-Epo level in PV, Epo levels were measured before and after heat treatment and concentration of samples from normals and polycythaemics. It was found that the levels of immunoreactive material increased after heat treatment and 40 times concentration in samples from normals and patients with secondary polycythaemias, but decreased in PV. We conclude that the Epo levels in serum in the low range measured by our and previous RIA:s probably are not true Epo levels but are partly due to an unspecific serum effect, that was removed by heat treatment.

  4. Erythropoietin abuse and erythropoietin gene doping: detection strategies in the genomic era.

    Science.gov (United States)

    Diamanti-Kandarakis, Evanthia; Konstantinopoulos, Panagiotis A; Papailiou, Joanna; Kandarakis, Stylianos A; Andreopoulos, Anastasios; Sykiotis, Gerasimos P

    2005-01-01

    The administration of recombinant human erythropoietin (rhEPO) increases the maximum oxygen consumption capacity, and is therefore abused as a doping method in endurance sports. The detection of erythropoietin (EPO) abuse is based on direct pharmacological and indirect haematological approaches, both of which have several limitations. In addition, current detection methods cannot cope with the emerging doping strategies of EPO mimicry, analogues and gene doping, and thus novel detection strategies are urgently needed. Direct detection methods for EPO misuse can be either pharmacological approaches that identify exogenous substances based on their physicochemical properties, or molecular methods that recognise EPO transgenes or gene transfer vectors. Since direct detection with molecular methods requires invasive procedures, it is not appropriate for routine screening of large numbers of athletes. In contrast, novel indirect methods based on haematological and/or molecular profiling could be better suited as screening tools, and athletes who are suspect of doping would then be submitted to direct pharmacological and molecular tests. This article reviews the current state of the EPO doping field, discusses available detection methods and their shortcomings, outlines emerging pharmaceutical and genetic technologies in EPO misuse, and proposes potential directions for the development of novel detection strategies.

  5. 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

    they are involved in tissue protection. However, the use of erythropoietin as a neuroprotective agent may be hampered by its erythropoietic activity. Therefore, developing non-haematopoietic erythropoietin mimetics is important. Based on the crystal structure of the complex of erythropoietin and its receptor, we...... 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...

  6. 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...

  7. 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

    2018-06-01

    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 optic neuropathy and may represent a promising treatment for this disorder.

  8. 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.

  9. Haemostatic aspects of recombinant human erythropoietin in colorectal surgery

    DEFF Research Database (Denmark)

    Poulsen, K A; Qvist, N; Winther, K

    1998-01-01

    OBJECTIVE: To find out whether recombinant human erythropoietin (r-HuEPO) given perioperatively has any effect on haemostatic activity in patients undergoing elective colorectal resection. DESIGN: A placebo-controlled double-blind study. SETTING: Odense university hospital, Denmark. SUBJECTS: 24...

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

    African Journals Online (AJOL)

    O2-induced hyperpermeability. H Zhang, Y Gong, X Wu, Y Shi, L Yin, Y Qiu. Abstract. 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 ...

  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. Reduction in central venous pressure enhances erythropoietin synthesis

    DEFF Research Database (Denmark)

    Montero, D.; Rauber, S.; Gøtze, Jens Peter

    2016-01-01

    AIMS: Erythropoiesis is a tightly controlled biological event, but its regulation under non-hypoxic conditions, however, remains unresolved. We examined whether acute changes in central venous blood pressure (CVP) elicited by whole-body tilting affect erythropoietin (EPO) concentration according...

  13. Protein kinase C alpha controls erythropoietin receptor signaling.

    NARCIS (Netherlands)

    M.M. von Lindern (Marieke); M. Parren-Van Amelsvoort (Martine); T.B. van Dijk (Thamar); E. Deiner; B. Löwenberg (Bob); E. van den Akker (Emile); S. van Emst-de Vries (Sjenet); P.J. Willems (Patrick); H. Beug (Hartmut)

    2000-01-01

    textabstractProtein kinase C (PKC) is implied in the activation of multiple targets of erythropoietin (Epo) signaling, but its exact role in Epo receptor (EpoR) signal transduction and in the regulation of erythroid proliferation and differentiation remained elusive. We

  14. Protein kinase C alpha controls erythropoietin receptor signaling

    NARCIS (Netherlands)

    von Lindern, M.; Parren-van Amelsvoort, M.; van Dijk, T.; Deiner, E.; van den Akker, E.; van Emst-de Vries, S.; Willems, P.; Beug, H.; Löwenberg, B.

    2000-01-01

    Protein kinase C (PKC) is implied in the activation of multiple targets of erythropoietin (Epo) signaling, but its exact role in Epo receptor (EpoR) signal transduction and in the regulation of erythroid proliferation and differentiation remained elusive. We analyzed the effect of PKC inhibitors

  15. 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

  16. Regulation of VEGF signaling by membrane traffic.

    Science.gov (United States)

    Horowitz, Arie; Seerapu, Himabindu Reddy

    2012-09-01

    Recent findings have drawn attention to the role of membrane traffic in the signaling of vascular endothelial growth factor (VEGF). The significance of this development stems from the pivotal function of VEGF in vasculogenesis and angiogenesis. The outline of the regulation of VEGF receptor (VEGFR) signaling by membrane traffic is similar to that of the epidermal growth factor receptor (EGFR), a prototype of the intertwining between membrane traffic and signaling. There are, however, unique features in VEGFR signaling that are conferred in part by the involvement of the co-receptor neuropilin (Nrp). Nrp1 and VEGFR2 are integrated into membrane traffic through the adaptor protein synectin, which recruits myosin VI, a molecular motor that drives inward trafficking [17,21,64]. The recent detection of only mild vascular defects in a knockin mouse model that expresses Nrp1 lacking a cytoplasmic domain [104], questions the co-receptor's role in VEGF signaling and membrane traffic. The regulation of endocytosis by ephrin-B2 is another feature unique to VEGR2/3 [18,19], but it awaits a mechanistic explanation. Current models do not fully explain how membrane traffic bridges between VEGFR and the downstream effectors that produce its functional outcome, such as cell migration. VEGF-A appears to accomplish this task in part by recruiting endocytic vesicles carrying RhoA to internalized active VEGFR2 [58]. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Prognostic significance of erythropoietin in pancreatic adenocarcinoma.

    Directory of Open Access Journals (Sweden)

    Thilo Welsch

    Full Text Available BACKGROUND: Erythropoietin (Epo administration has been reported to have tumor-promoting effects in anemic cancer patients. We investigated the prognostic impact of endogenous Epo in patients with pancreatic ductal adenocarcinoma (PDAC. METHODOLOGY: The clinico-pathological relevance of hemoglobin (Hb, n = 150, serum Epo (sEpo, n = 87 and tissue expression of Epo/Epo receptor (EpoR, n = 104 was analyzed in patients with PDAC. Epo/EpoR expression, signaling, growth, invasion and chemoresistance were studied in Epo-exposed PDAC cell lines. RESULTS: Compared to donors, median preoperative Hb levels were reduced by 15% in both chronic pancreatitis (CP, p<0.05 and PDAC (p<0.001, reaching anemic grade in one third of patients. While inversely correlating to Hb (r = -0.46, 95% of sEPO values lay within the normal range. The individual levels of compensation were adequate in CP (observed to predicted ratio, O/P = 0.99 but not in PDAC (O/P = 0.85. Strikingly, lower sEPO values yielding inadequate Epo responses were prominent in non-metastatic M0-patients, whereas these parameters were restored in metastatic M1-group (8 vs. 13 mU/mL; O/P = 0.82 vs. 0.96; p<0.01--although Hb levels and the prevalence of anemia were comparable. Higher sEpo values (upper quartile ≥ 16 mU/ml were not significantly different in M0 (20% and M1 (30% groups, but were an independent prognostic factor for shorter survival (HR 2.20, 10 vs. 17 months, p<0.05. The pattern of Epo expression in pancreas and liver suggested ectopic release of Epo by capillaries/vasa vasorum and hepatocytes, regulated by but not emanating from tumor cells. Epo could initiate PI3K/Akt signaling via EpoR in PDAC cells but failed to alter their functions, probably due to co-expression of the soluble EpoR isoform, known to antagonize Epo. CONCLUSION/SIGNIFICANCE: Higher sEPO levels counteract anemia but worsen outcome in PDAC patients. Further trials are required to clarify how overcoming a sEPO threshold

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

    DEFF Research Database (Denmark)

    Christensen, Britt; Lundby, Carsten; Jessen, Niels

    2012-01-01

    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...... 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...

  19. 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...

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

    International Nuclear Information System (INIS)

    Jo, Hye-Ryeong; Kim, Yong-Seok; Son, Hyeon

    2016-01-01

    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. 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......-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...

  2. 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.

  3. 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....... 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....

  4. Clinical trial experience using erythropoietin during radiation therapy

    International Nuclear Information System (INIS)

    Lavey, R.S.

    1998-01-01

    Oncologists have several reasons for trying to maintain or increase hemoglobin levels in their patients during therapy. Relief of the symptoms of anemia, including fatigue and dyspnea, are traditional, well-accepted indications. A newer rationale is to enhance the efficacy of radiation therapy and/or chemotherapy in controlling tumors. A laboratory animal study found that administration of recombinant human erythropoietin (rHuEPO) increased intratumoral median oxygen levels and diminished the proportion of measurements in the very low ( [de

  5. L-arginine supplementation enhances exhaled NO, breath condensate VEGF, and headache at 4,342 m.

    Science.gov (United States)

    Mansoor, Jim K; Morrissey, Brian M; Walby, William F; Yoneda, Ken Y; Juarez, Maya; Kajekar, Radhika; Severinghaus, John W; Eldridge, Marlowe W; Schelegle, Edward S

    2005-01-01

    We examined the effect of dietary supplementation with L-arginine on breath condensate VEGF, exhaled nitric oxide (NO), plasma erythropoietin, symptoms of acute mountain sickness, and respiratory related sensations at 4,342 m through the course of 24 h in seven healthy male subjects. Serum L-arginine levels increased in treated subjects at time 0, 8, and 24 h compared with placebo, indicating the effectiveness of our treatment. L-arginine had no significant effect on overall Lake Louise scores compared with placebo. However, there was a significant increase in headache within the L-arginine treatment group at 12 h compared with time 0, a change not seen in the placebo condition between these two time points. There was a trend (p = 0.087) toward greater exhaled NO and significant increases in breath condensate VEGF with L-arginine treatment, but no L-arginine effect on serum EPO. These results suggest that L-arginine supplementation increases HIF-1 stabilization in the lung, possibly through a NO-dependent pathway. In total, our observations indicate that L-arginine supplementation is not beneficial in the prophylactic treatment of AMS.

  6. 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.

  7. The potential of erythropoietin to treat asphyxia in newborns

    Directory of Open Access Journals (Sweden)

    Pet GC

    2014-11-01

    Full Text Available Gillian C Pet, Sandra E Juul Department of Pediatrics, Division of Neonatology, University of Washington, Seattle, WA, USA Abstract: Perinatal asphyxia is a cause of significant neonatal morbidity worldwide. Lack of oxygenation and perfusion to the neonatal brain leads to energy failure and cell death. Currently, therapeutic hypothermia is the standard of care for term infants with hypoxic-ischemic encephalopathy, but as it has shown only modest effects on survival and morbidity, additional neuroprotective agents are needed. Erythropoietin has been extensively studied as a neuroprotective agent for infants who suffer a hypoxic-ischemic brain injury. It has multiple mechanisms of action, in both preventing cell death and promoting tissue repair. Studies have progressed over time from in vitro to in vivo studies, first in animals and now in humans, with several Phase I/II trials completed and Phase III trials underway. As therapeutic hypothermia has become the standard of care in treating term infants with hypoxic-ischemic encephalopathy, studies must now evaluate other neuroprotective agents, including erythropoietin, used in concert with therapeutic hypothermia. Erythropoietin has shown promise as a neuroprotective agent in animal and human models, both alone and together with hypothermia. Keywords: neonate, brain injury

  8. Identification of functional VEGF receptors on human platelets.

    Science.gov (United States)

    Selheim, Frode; Holmsen, Holm; Vassbotn, Flemming S

    2002-02-13

    Platelets secrete platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) upon stimulation. We have demonstrated that platelets have functionally active PDGF alpha-receptors, a transmembrane tyrosine kinase involved in negative feedback regulation. Here we demonstrate the presence of the related VEGF receptors fms-like tyrosine kinase-1 and kinase-insert domain region on human platelets. VEGF itself did not cause platelet aggregation. However, addition of exogenous VEGF to SFRLLN or thrombin-stimulated platelets potentiated platelet aggregation. Moreover, thrombin-induced phosphoinositide 3-kinase and mitogen-activated protein kinase activity were enhanced in the presence of VEGF.

  9. AKT increases VEGF expression in tumor cells by transactivating the proximal VEGF promoter

    International Nuclear Information System (INIS)

    Pore, N.; Bernhard, E.J.; Shu, H.-K.; Li, B.; O'Rourke, D.M.; Maity, A.; Haas-Kogan, D.

    2003-01-01

    Vascular endothelial growth factor (VEGF) is overexpressed in many cancers including glioblastomas and may contribute to their growth. Epidermal growth factor receptor (EGFR) amplification and loss of PTEN, commonly found in glioblastomas leading to increase phosphatidylinositol-3-kinase (PI3K) activity and VEGF expression. In the current study we show that AKT, which is downstream of PI3K, regulates VEGF expression. U87MG human glioblastoma cells lack wildtype PTEN and express high levels of phosphorylated AKT. Over expression of AKT either by stable expression in immortalized human astrocytes or by transduction with adenovirus containing activated myristoylated AKT in SF188 glioblastoma cells increases VEGF expression. Moreover the elevation of angiogenesis by constitutively expressed AKT is further confirmed by in vivo matrigel plug assay in nude mice. The upregulation of VEGF by AKT is mediated through a region in the proximal promoter located between -88 and -70 (+1 is transcription start site). In transient transfection activity of a luciferase reporter containing the -88/+54 region of the VEGF promoter is increased by cotransfection with myristoylated AKT and downregulated by a dominant negative AKT expression vector. Mutation of the putative Sp1 binding sites located in the -88/-70 region we show that AKT acts through Sp1 to transactivate the VEGF promoter. Cotransfection of the VEGF promoter reporter with both Sp1 and myristoylated AKT expression vectors increases promoter activity to a greater extent than either Sp1 or Akt by itself. In vivo phosphate labeling of proteins reveals that AKT leads to increased Sp1 phosphorylation. Gel shift assays using a radio labeled probe corresponding to nucleotides -88 through -66 in the promoter show increased binding with nuclear extracts from cells transduced with adenovirus expressing myristoylated AKT. In conclusion, our results suggest that loss of PTEN leads to increased VEGF expression by increasing AKT

  10. VEGF promotes tumorigenesis and angiogenesis of human glioblastoma stem cells

    International Nuclear Information System (INIS)

    Oka, Naoki; Soeda, Akio; Inagaki, Akihito; Onodera, Masafumi; Maruyama, Hidekazu; Hara, Akira; Kunisada, Takahiro; Mori, Hideki; Iwama, Toru

    2007-01-01

    There is increasing evidence for the presence of cancer stem cells (CSCs) in malignant brain tumors, and these CSCs may play a pivotal role in tumor initiation, growth, and recurrence. Vascular endothelial growth factor (VEGF) promotes the proliferation of vascular endothelial cells (VECs) and the neurogenesis of neural stem cells. Using CSCs derived from human glioblastomas and a retrovirus expressing VEGF, we examined the effects of VEGF on the properties of CSCs in vitro and in vivo. Although VEGF did not affect the property of CSCs in vitro, the injection of mouse brains with VEGF-expressing CSCs led to the massive expansion of vascular-rich GBM, tumor-associated hemorrhage, and high morbidity, suggesting that VEGF promoted tumorigenesis via angiogenesis. These results revealed that VEGF induced the proliferation of VEC in the vascular-rich tumor environment, the so-called stem cell niche

  11. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. 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.

  14. 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...

  15. 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.

  16. VEGF blockade inhibits angiogenesis and reepithelialization of endometrium.

    Science.gov (United States)

    Fan, Xiujun; Krieg, Sacha; Kuo, Calvin J; Wiegand, Stanley J; Rabinovitch, Marlene; Druzin, Maurice L; Brenner, Robert M; Giudice, Linda C; Nayak, Nihar R

    2008-10-01

    Despite extensive literature on vascular endothelial growth factor (VEGF) expression and regulation by steroid hormones, the lack of clear understanding of the mechanisms of angiogenesis in the endometrium is a major limitation for use of antiangiogenic therapy targeting endometrial vessels. In the current work, we used the rhesus macaque as a primate model and the decidualized mouse uterus as a murine model to examine angiogenesis during endometrial breakdown and regeneration. We found that blockade of VEGF action with VEGF Trap, a potent VEGF blocker, completely inhibited neovascularization during endometrial regeneration in both models but had no marked effect on preexisting or newly formed vessels, suggesting that VEGF is essential for neoangiogenesis but not survival of mature vessels in this vascular bed. Blockade of VEGF also blocked reepithelialization in both the postmenstrual endometrium and the mouse uterus after decidual breakdown, evidence that VEGF has pleiotropic effects in the endometrium. In vitro studies with a scratch wound assay showed that the migration of luminal epithelial cells during repair involved signaling through VEGF receptor 2-neuropilin 1 (VEGFR2-NP1) receptors on endometrial stromal cells. The leading front of tissue growth during endometrial repair was strongly hypoxic, and this hypoxia was the local stimulus for VEGF expression and angiogenesis in this tissue. In summary, we provide novel experimental data indicating that VEGF is essential for endometrial neoangiogenesis during postmenstrual/postpartum repair.

  17. Endogenous Vascular Endothelial Growth Factor-A (VEGF-A) Maintains Endothelial Cell Homeostasis by Regulating VEGF Receptor-2 Transcription*

    Science.gov (United States)

    E, Guangqi; Cao, Ying; Bhattacharya, Santanu; Dutta, Shamit; Wang, Enfeng; Mukhopadhyay, Debabrata

    2012-01-01

    Vascular endothelial growth factor A (VEGF-A) is one of the most important factors controlling angiogenesis. Although the functions of exogenous VEGF-A have been widely studied, the roles of endogenous VEGF-A remain unclear. Here we focused on the mechanistic functions of endogenous VEGF-A in endothelial cells. We found that it is complexed with VEGF receptor 2 (VEGFR-2) and maintains a basal expression level for VEGFR-2 and its downstream signaling activation. Endogenous VEGF-A also controls expression of key endothelial specific genes including VEGFR-2, Tie-2, and vascular endothelial cadherin. Of importance, endogenous VEGF-A differs from exogenous VEGF-A by regulating VEGFR-2 transcription through mediation of FoxC2 binding to the FOX:ETS motif, and the complex formed by endogenous VEGF-A with VEGFR-2 is localized within the EEA1 (early endosome antigen 1) endosomal compartment. Taken together, our results emphasize the importance of endogenous VEGF-A in endothelial cells by regulating key vascular proteins and maintaining the endothelial homeostasis. PMID:22167188

  18. Therapy with recombinant human erythropoietin in patients with myelodysplastic syndromes.

    Science.gov (United States)

    Stone, R M; Bernstein, S H; Demetri, G; Facklam, D P; Arthur, K; Andersen, J; Aster, J C; Kufe, D

    1994-10-01

    We conducted a Phase I-II trial of recombinant human erythropoietin-beta (rhEPO) in patients with myelodysplastic syndrome (MDS). Patients with anemia and pathologically confirmed MDS were eligible for the study. Treatment consisted of rhEPO by subcutaneous injection thrice weekly for 6 weeks at one of three dose levels (100 U/kg (three patients), 200 U/kg (three patients) and 400 U/kg (14 patients)). Ferrous sulfate (325 mg po tid) was also administered if the transferrin saturation was below 30% (two patients). Patients were monitored with weekly CBC, white cell differential, and reticulocyte counts. Bone marrow examinations were performed at the conclusion of the treatment period and after a 2 week washout period. Patients who responded to therapy were continued on rhEPO at the same dose for 6 additional months. Response criteria included: 50% reduction in transfusion requirements compared with the 6 week pre-study period; doubling of reticulocyte count that was maintained on two determinations at least 1 week apart; or an increase in hemoglobin by at least 1.2 gm/dl without transfusions. Pre-treatment factors potentially predictive of response were analyzed by univariate analysis and in a multivariate fashion by classification and regression trees. Seven of the twenty patients sustained an untransfused rise in serum hemoglobin > or = 1.2 gm/dl. Four of the sixteen patients (including three of seven patients experiencing a rise in serum hemoglobin) who were transfusion-dependent prior to the study achieved a reduction or elimination of their transfusion requirements. Five of thirteen patients who received rhEPO during the extension phase had a continued response. A low baseline erythropoietin level (< 50 mU/ml) was the best predictor of hemoglobin response when controlling for other variables. rhEPO has a role in the treatment of certain patients with MDS, particularly in those whose endogenous serum erythropoietin levels are not markedly elevated.

  19. 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.

  20. 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)

  1. Pharmacokinetics of erythropoietin in intact and anephric dogs

    International Nuclear Information System (INIS)

    Fu, J.S.; Lertora, J.J.; Brookins, J.; Rice, J.C.; Fisher, J.W.

    1988-01-01

    The present studies were performed to determine the pharmacokinetic parameters of erythropoietin in intact and anephric dogs by use of unlabeled crude native erythropoietin (nEp) and iodine 125-labeled purified recombinant erythropoietin (rEp) given by intravenous infusion for 15 minutes. Sephadex G-75 gel filtration was used to confirm that the 125I-rEp molecule remained iodinated in dog plasma during the 24-hour period of these studies. The plasma disappearance of erythropoietin conformed to a biexponential equation for both nEp and 125I-rEp, with the central compartment being larger than the peripheral compartment. The mean distribution half-life of 75.3 +/- 21.2 minutes for nEp was significantly (p less than 0.05) longer than that of 125I-rEp (23.7 +/- 5.0 minutes) in intact dogs. The intercompartmental clearance (CIic) for nEp (0.018 +/- 0.006 L/kg/hr) was significantly smaller than that of 125I-rEp (0.068 +/- 0.018 L/kg/hr) in intact dogs (p less than 0.05). There were no significant differences in apparent volume of distribution, elimination half-life, and elimination clearance (CIe) for nEp and rEp in intact dogs. The mean elimination half-life for 125I-rEp in intact dogs (9.0 +/- 0.6 hours) and anephric dogs (13.8 +/- 1.4 hours) was significantly different (p less than 0.05). The CIe for 125I-rEp in anephric dogs (0.008 +/- 0.001 L/kg/hr) was significantly (p less than 0.05) smaller than that of 125I-rEp in intact dogs (0.011 +/- 0.001 L/kg/hr). There were no significant differences in apparent volume of distribution, distribution half-life, and CIic for 125I-rEp in intact and anephric dogs

  2. Development of a VHH-Based Erythropoietin Quantification Assay

    DEFF Research Database (Denmark)

    Kol, Stefan; Beuchert Kallehauge, Thomas; Adema, Simon

    2015-01-01

    Erythropoietin (EPO) quantification during cell line selection and bioreactor cultivation has traditionally been performed with ELISA or HPLC. As these techniques suffer from several drawbacks, we developed a novel EPO quantification assay. A camelid single-domain antibody fragment directed against...... human EPO was evaluated as a capturing antibody in a label-free biolayer interferometry-based quantification assay. Human recombinant EPO can be specifically detected in Chinese hamster ovary cell supernatants in a sensitive and pH-dependent manner. This method enables rapid and robust quantification...

  3. Renal Involvement in Preeclampsia: Similarities to VEGF Ablation Therapy

    Directory of Open Access Journals (Sweden)

    Janina Müller-Deile

    2011-01-01

    Full Text Available Glomerular VEGF expression is critical for the maintenance and function of an intact filtration barrier. Alterations in glomerular VEGF bioavailability result in endothelial as well as in podocyte damage. Renal involvement in preeclampsia includes proteinuria, podocyturia, elevated blood pressure, edema, glomerular capillary endotheliosis, and thrombotic microangiopathy. At least the renal signs, symptoms, and other evidence can sufficiently be explained by reduced VEGF levels. The aim of this paper was to summarize our pathophysiological understanding of the renal involvement of preeclampsia and point out similarities to the renal side effects of VEGF-ablation therapy.

  4. The effect of erythropoietin on healing of obstructive vs nonobstructive left colonic anastomosis: an experimental study

    Directory of Open Access Journals (Sweden)

    Renda Nurten

    2007-05-01

    Full Text Available Abstract Background Anastomotic leakage is an important problem following primary resection in the left colon and is even more prominent when obstruction is present. We aimed to evaluate the possible effects of erythropoietin on the healing of anastomosis under both obstructive and non-obstructive states. Methods Forty male Wistar albino rats were divided into four groups. In group I, two cm left colonic resection and primary anastomosis were done. In group II, left colon were completely ligated and 24 hours later animals were re-operated for segmental resection. The same procedures were performed for rats in group III and IV in respect to group I and II and, 500 IU/kg a day erythropoietin were given in the latter two groups for seven days. For the quantative description of anastomotic healing mechanical, biochemical and histopathological parameters were employed on the seventh day and the animals were sacrificied. Results Although erythropoietin had positive effects on bursting pressure in group IV when compared to group II, it has no effect in group III. Despite the increased tissue hydroxyproline levels in group IV, erythropoietin failed to show any effects in group III. Erythropoietin had positive effects on neovascularization, fibroblast proliferiation and storage of collagen in group IV. Conclusion We failed to find any direct and evident effects of erythropoietin on healing of left colonic anastomosis. On the other hand, erythropoietin might prevent negative effects of obstruction on healing.

  5. Granulocyte-Colony Stimulating Factor Receptor, Tissue Factor, and VEGF-R Bound VEGF in Human Breast Cancer In Loco.

    Science.gov (United States)

    Wojtukiewicz, Marek Z; Sierko, Ewa; Skalij, Piotr; Kamińska, Magda; Zimnoch, Lech; Brekken, Ralf A; Thorpe, Philip E

    2016-01-01

    Doxorubicin and docetaxel-based chemotherapy regimens used in breast cancer patients are associated with high risk of febrile neutropenia (FN). Granulocyte colony-stimulating factors (G-CSF) are recommended for both treating and preventing chemotherapy-induced neutropenia. Increased thrombosis incidence in G-CSF treated patients was reported; however, the underlying mechanisms remain unclear. The principal activator of blood coagulation in cancer is tissue factor (TF). It additionally contributes to cancer progression and stimulates angiogenesis. The main proangiogenic factor is vascular endothelial growth factor (VEGF). The aim of the study was to evaluate granulocyte-colony stimulating factor receptor (G-CSFR), tissue factor (TF) expression and vascular endothelial growth factor receptor (VEGF-R) bound VEGF in human breast cancer in loco. G-CSFR, TF and VEGFR bound VEGF (VEGF: VEGFR) were assessed in 28 breast cancer tissue samples. Immunohistochemical (IHC) methodologies according to ABC technique and double staining IHC procedure were employed utilizing antibodies against G-CSFR, TF and VEGF associated with VEGFR (VEGF: VEGFR). Expression of G-CSFR was demonstrated in 20 breast cancer tissue specimens (71%). In 6 cases (21%) the expression was strong (IRS 9-12). Strong expression of TF was observed in all investigated cases (100%). Moreover, expression of VEGF: VEGFR was visualized in cancer cells (IRS 5-8). No presence of G-CSFR, TF or VEGF: VEGFR was detected on healthy breast cells. Double staining IHC studies revealed co-localization of G-CSFR and TF, G-CSFR and VEGF: VEGFR, as well as TF and VEGF: VEGFR on breast cancer cells and ECs. The results of the study indicate that GCSFR, TF and VEGF: VEGFR expression as well as their co-expression might influence breast cancer biology, and may increase thromboembolic adverse events incidence.

  6. 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

  7. Elevated IGFIR expression regulating VEGF and VEGF-C predicts lymph node metastasis in human colorectal cancer

    International Nuclear Information System (INIS)

    Zhang, Chunhui; Hao, Li; Wang, Liang; Xiao, Yichuan; Ge, Hailiang; Zhu, Zhenya; Luo, Yunbao; Zhang, Yi; Zhang, Yanyun

    2010-01-01

    Insulin-like growth factor-I receptor (IGFIR) has been shown to regulate the tumor development. The objective of the current study is to determine the association of IGFIR with lymph node metastasis and to explore the related mechanism in human colorectal cancer in clinic. In a random series of 98 colorectal cancer patients, the expressions of IGFIR, vascular endothelial growth factor (VEGF) and VEGF-C were investigated by immunohistochemistry, and the association of these expressions with lymph node metastasis was statistically analyzed. The expressions of VEGF and VEGF-C in colorectal cancer cells stimulated with IGF-I were also examined by real-time quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. Higher rates of IGFIR (46%), VEGF (53%), and VEGF-C (46%) expression were found in colorectal cancer tissues than in normal and colorectal adenoma tissues. These expressions were significantly associated with clinicopathologic factors and lymph node status. We also found the concomitant high expressions of IGFIR/VEGF (P < 0.001) and IGFIR/VEGF-C (P = 0.001) had a stronger correlation with lymph node metastasis than did each alone or both low expressions. In addition, IGF-I could effectively induce the VEGF and VEGF-C mRNA expression and protein secretion in colorectal cancer cells expressing IGFIR molecules. Moreover, Patients who had strong staining for IGFIR, VEGF and VEGF-C showed significantly less favorable survival rates compared with patients who had low staining for these molecules (P < 0.001). The survival rates of patients who were both high expression of IGFIR/VEGF and IGFIR/VEGF-C also were significantly lower compared with patients who were negative or one of high expression of these molecules (P < 0.001). Together the findings indicated for the first time that simultaneous examination of the expressions of IGFIR, VEGF and VEGF-C will benefit the diagnosis of lymph node metastasis in order to assay the

  8. 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.

  9. Clinical significance of the VEGF level in urinary bladder carcinoma.

    Science.gov (United States)

    Sankhwar, Monica; Sankhwar, Satya Narayan; Abhishek, Amar; Rajender, Singh

    2015-01-01

    To investigate the correlation of Vascular Endothelial Growth Factor (VEGF) and micro-vessel density (MVD) with urinary bladder tumor and its stage. The study was conducted between January 2010 and December 2012. The study included screening of 122 patients at elevated risk for bladder cancer, of which 35 patients were finally enrolled in the study. Diagnosis was made on the basis of urine cytology, radiological investigation (ultrasound KUB, and CT-scan) and histopathology. Thirty-five normal cancer-free individuals were enrolled as controls. Human VEGF levels were measured using an enzyme linked immunoassay and protein content (pg/mg protein) by Lowry method. SPSS for Windows version 10.0.7 (SPSS, Chicago, IL, USA) was used for statistical analysis of the data. Mean urine VEGF level in the cases was significantly higher in comparison to the control group. There was a direct correlation between VEGF level and tumor stage. Mean urine VEGF values were minimum in the control group (22.75 ± 15.41 pg/mg creatinine) and maximum in stage IV patients (180.15 ± 75.93 pg/mg creatinine). Tissue VEGF levels also showed a similar trend of increase with increase in stage. Urine VEGF level also showed a correlation with tissue VEGF level. Similarly, MVD showed a significant increase with increase in tumor stage. A correlation between bladder cancer and MVD and VEGF suggest that the latter can serve as markers for therapeutic guidance. This is the first study from India on clinical and pathological correlation among urine VEGF, tumor tissue VEGF levels, and Micro Vessel Density (MVD) in urinary bladder cancer patients.

  10. Predominance of granulocytopoiesis in bone marrow grafts in the omenta of mice treated with erythropoietin

    International Nuclear Information System (INIS)

    Meck, R.A.; Laissue, J.A.

    1977-01-01

    The effects of erythropoietin on the differentiation of murine bone marrow injected into the omenta of x-irradiated mice were investigated. Experimental hosts were injected with 2.5 units of erythropoietin on days 0-7 and sacrificed on day 10. Control hosts were injected with saline or sheep serum. After 10 days the grafts were > 95% granulocytic regardless of host treatment. Since these grafts contain multipotent hematopoietic stem cells and the experimental hosts were exposed to large doses of erythropoietin, the results of this experiment indicate that a specialized microenvironment is required for murine erythropoiesis in vivo. (author)

  11. Structure and thermal expansion of Ca9Gd(VO4)7: A combined powder-diffraction and dilatometric study of a Czochralski-grown crystal

    Science.gov (United States)

    Paszkowicz, Wojciech; Shekhovtsov, Alexei; Kosmyna, Miron; Loiko, Pavel; Vilejshikova, Elena; Minikayev, Roman; Romanowski, Przemysław; Wierzchowski, Wojciech; Wieteska, Krzysztof; Paulmann, Carsten; Bryleva, Ekaterina; Belikov, Konstantin; Fitch, Andrew

    2017-11-01

    Materials of the Ca9RE(VO4)7 (CRVO) formula (RE = rare earth) and whitlockite-related structures are considered for applications in optoelectronics, e.g., in white-light emitting diodes and lasers. In the CRVO structure, the RE atoms are known to share the site occupation with Ca atoms at two or three among four Ca sites, with partial occupancy values depending on the choice of the RE atom. In this work, the structure and quality of a Czochralski-grown crystal of this family, Ca9Gd(VO4)7 (CGVO), are studied using X-ray diffraction methods. The room-temperature structure is refined using the powder diffraction data collected at a high-resolution synchrotron beamline ID22 (ESRF, Grenoble); for comparison purposes, a laboratory diffraction pattern was collected and analyzed, as well. The site occupancies are discussed on the basis of comparison with literature data of isostructural synthetic crystals of the CRVO series. The results confirm the previously reported site-occupation scheme and indicate a tendency of the CGVO compound to adopt a Gd-deficient composition. Moreover, the thermal expansion coefficient is determined for CGVO as a function of temperature in the 302-1023 K range using laboratory diffraction data. Additionally, for CGVO and six other single crystals of the same family, thermal expansion is studied in the 298-473 K range, using the dilatometric data. The magnitude and anisotropy of thermal expansion, being of importance for laser applications, are discussed for these materials.

  12. Regulation of alternative VEGF-A mRNA splicing is a therapeutic target for analgesia.

    Science.gov (United States)

    Hulse, R P; Beazley-Long, N; Hua, J; Kennedy, H; Prager, J; Bevan, H; Qiu, Y; Fernandes, E S; Gammons, M V; Ballmer-Hofer, K; Gittenberger de Groot, A C; Churchill, A J; Harper, S J; Brain, S D; Bates, D O; Donaldson, L F

    2014-11-01

    Vascular endothelial growth factor-A (VEGF-A) is best known as a key regulator of the formation of new blood vessels. Neutralization of VEGF-A with anti-VEGF therapy e.g. bevacizumab, can be painful, and this is hypothesized to result from a loss of VEGF-A-mediated neuroprotection. The multiple vegf-a gene products consist of two alternatively spliced families, typified by VEGF-A165a and VEGF-A165b (both contain 165 amino acids), both of which are neuroprotective. Under pathological conditions, such as in inflammation and cancer, the pro-angiogenic VEGF-A165a is upregulated and predominates over the VEGF-A165b isoform. We show here that in rats and mice VEGF-A165a and VEGF-A165b have opposing effects on pain, and that blocking the proximal splicing event - leading to the preferential expression of VEGF-A165b over VEGF165a - prevents pain in vivo. VEGF-A165a sensitizes peripheral nociceptive neurons through actions on VEGFR2 and a TRPV1-dependent mechanism, thus enhancing nociceptive signaling. VEGF-A165b blocks the effect of VEGF-A165a. After nerve injury, the endogenous balance of VEGF-A isoforms switches to greater expression of VEGF-Axxxa compared to VEGF-Axxxb, through an SRPK1-dependent pre-mRNA splicing mechanism. Pharmacological inhibition of SRPK1 after traumatic nerve injury selectively reduced VEGF-Axxxa expression and reversed associated neuropathic pain. Exogenous VEGF-A165b also ameliorated neuropathic pain. We conclude that the relative levels of alternatively spliced VEGF-A isoforms are critical for pain modulation under both normal conditions and in sensory neuropathy. Altering VEGF-Axxxa/VEGF-Axxxb balance by targeting alternative RNA splicing may be a new analgesic strategy. Copyright © 2014. Published by Elsevier Inc.

  13. The power of VEGF (vascular endothelial growth factor) family molecules.

    Science.gov (United States)

    Thomas, Jean-Leon; Eichmann, Anne

    2013-05-01

    Vascular endothelial growth factors (VEGFs) and their high-affinity tyrosine kinase VEGF receptors (VEGFRs) are key regulators of both angiogenesis and neurogenesis. The current issue of CMLS discusses recent literature and work implementing these signals in nervous system development, maintenance and disease pathology.

  14. 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.

  15. VEGF improves survival of mesenchymal stem cells in infarcted hearts

    International Nuclear Information System (INIS)

    Pons, Jennifer; Huang Yu; Arakawa-Hoyt, Janice; Washko, Daniel; Takagawa, Junya; Ye, Jianqin; Grossman, William; Su Hua

    2008-01-01

    Bone marrow-derived mesenchymal stem cells (MSC) are a promising source for cell-based treatment of myocardial infarction (MI), but existing strategies are restricted by low cell survival and engraftment. We examined whether vascular endothelial growth factor (VEGF) improve MSC viability in infracted hearts. We found long-term culture increased MSC-cellular stress: expressing more cell cycle inhibitors, p16 INK , p21 and p19 ARF . VEGF treatment reduced cellular stress, increased pro-survival factors, phosphorylated-Akt and Bcl-xL expression and cell proliferation. Co-injection of MSCs with VEGF to MI hearts increased cell engraftment and resulted in better improvement of cardiac function than that injected with MSCs or VEGF alone. In conclusion, VEGF protects MSCs from culture-induce cellular stress and improves their viability in ischemic myocardium, which results in improvements of their therapeutic effect for the treatment of MI

  16. VEGF signaling inside vascular endothelial cells and beyond.

    Science.gov (United States)

    Eichmann, Anne; Simons, Michael

    2012-04-01

    Vascular endothelial growth factor-A (VEGF-A) has long been recognized as the key regulator of vascular development and function in health and disease. VEGF is a secreted polypeptide that binds to transmembrane tyrosine kinase VEGF receptors on the plasma membrane, inducing their dimerization, activation and assembly of a membrane-proximal signaling complex. Recent studies have revealed that many key events of VEGFR signaling occur inside the endothelial cell and are regulated by endosomal receptor trafficking. Plasma membrane VEGFR interacting molecules, including vascular guidance receptors Neuropilins and Ephrins also regulate VEGFR endocytosis and trafficking. VEGF signaling is increasingly recognized for its roles outside of the vascular system, notably during neural development, and blood vessels regulate epithelial branching morphogenesis. We review here recent advances in our understanding of VEGF signaling and its biological roles. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. The use of /sup 125/I recombinant DNA/sub 125/ derived human erythropoietin (R-HuEPO) as a replacement for /sup 125/I human urinary epo as tracer antigen in a radioimmunoassay for human epo

    International Nuclear Information System (INIS)

    Cotes, P.M.; Tam, R.C.; GainesDas, R.E.

    1987-01-01

    This paper represents evidence that in a radioimmunoassay for human erythropoietin, recombinant DNA derived human erythropoietin can replace highly purified human urinary erythropoietin in the preparation of radioiodinated tracer antigen

  18. 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.

  19. [Correction of anemia in hemodialysis, effect of intravenous iron without erythropoietin].

    Science.gov (United States)

    Alvo, Miriam; Elgueta, Leticia; Aragón, Henry; Cotera, Alejandro

    2002-08-01

    In the last two decades, the use of erythropoietin for the correction of anemia in hemodialysis patients has been recommended. In Chile, only 10% of hemodialysis patients use erythropoietin, therefore, the correction of iron deficiency must be optimized. To report the effects of intravenous iron without erythropoietin in the management of anemia in hemodialysis patients. Retrospective analysis of 42 patients that received intravenous ferrous sacharate in doses of 100 mg/week during 5 weeks and 100 mg bimonthly during six months. These patients did not receive erythropoietin. Thirty six patients had iron deficiency. Basal ferritin was 137 +/- 22 micrograms/l and increased to 321 +/- 28 micrograms/l after treatment. Packed red cell volume increased from 24 +/- 2% to 29 +/- 3%. No adverse effects were reported. Iron deficiency is frequent in hemodialyzed patients. Intraveineous iron is safe and effective in the treatment of iron deficiency in these patients.

  20. 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.

  1. High-dose phenobarbital or erythropoietin for the treatment of perinatal asphyxia in term newborns.

    Science.gov (United States)

    Avasiloaiei, Andreea; Dimitriu, Cristina; Moscalu, Mihaela; Paduraru, Luminita; Stamatin, Maria

    2013-10-01

    The aim of this study was to compare two neuroprotective strategies to supportive care in the treatment of perinatal asphyxia. A total of 67 term newborns with perinatal asphyxia were included and randomized into three groups: one group received supportive treatment; another group received a single dose of 40 mg/kg phenobarbital; and the third received three daily doses of 1000 IU/kg erythropoietin. The following parameters were analyzed: gestational age, birthweight, Apgar scores, cord blood pH, total serum antioxidant status (TAS), superoxide dismutase (SOD), glutathione peroxidase (GPx) and malondialdehyde (MDA). The newborns were included in the follow-up program and examined up to 18 months of age. TAS was higher in the erythropoietin group than in the other groups. SOD and GPx were lower for infants treated with phenobarbital or erythropoietin compared to control infants. MDA was lower in the erythropoietin group compared to the other groups, although the difference was not statistically significant (P > 0.05). The mortality rate was lower in the phenobarbital and erythropoietin groups (both 4.6%) than in the control group (17.4%). Long-term neurologic follow up showed a high incidence of sequelae in the control group compared to the phenobarbital and erythropoietin groups. Follow-up results were better in the phenobarbital group than in the erythropoietin group for motor and cognitive function at 3 and 6 months and worse for expressive language. At 18 months, however, the differences between these two groups were not significant. High-dose phenobarbital or erythropoietin along with supportive treatment has a positive influence on the outcome of newborns with perinatal asphyxia. Phenobarbital has the advantage of low cost and simplicity. © 2013 The Authors. Pediatrics International © 2013 Japan Pediatric Society.

  2. Discrete β-adrenergic mechanisms regulate early and late erythropoiesis in erythropoietin-resistant anemia.

    Science.gov (United States)

    Hasan, Shirin; Mosier, Michael J; Szilagyi, Andrea; Gamelli, Richard L; Muthumalaiappan, Kuzhali

    2017-10-01

    Anemia of critical illness is resistant to exogenous erythropoietin. Packed red blood cells transfusions is the only treatment option, and despite related cost and morbidity, there is a need for alternate strategies. Erythrocyte development can be divided into erythropoietin-dependent and erythropoietin-independent stages. We have shown previously that erythropoietin-dependent development is intact in burn patients and the erythropoietin-independent early commitment stage, which is regulated by β1/β2-adrenergic mechanisms, is compromised. Utilizing the scald burn injury model, we studied erythropoietin-independent late maturation stages and the effect of β1/β2, β-2, or β-3 blockade in burn mediated erythropoietin-resistant anemia. Burn mice were randomized to receive daily injections of propranolol (nonselective β1/β2 antagonist), nadolol (long-acting β1/β2 antagonist), butoxamine (selective β2 antagonist), or SR59230A (selective β3 antagonist) for 6 days after burn. Total bone marrow cells were characterized as nonerythroid cells, early and late erythroblasts, nucleated orthochromatic erythroblasts and enucleated reticulocyte subsets using CD71, Ter119, and Syto-16 by flow cytometry. Multipotential progenitors were probed for MafB expressing cells. Although propranolol improved early and late erythroblasts, only butoxamine and selective β3-antagonist administrations were positively reflected in the peripheral blood hemoglobin and red blood cells count. While burn impeded early commitment and late maturation stages, β1/β2 antagonism increased the early erythroblasts through commitment stages via β2 specific MafB regulation. β3 antagonism was more effective in improving overall red blood cells through late maturation stages. The study unfolds novel β2 and β3 adrenergic mechanisms orchestrating erythropoietin resistant anemia after burn, which impedes both the early commitment stage and the late maturation stages, respectively. Copyright © 2017

  3. 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.

  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......: This study provides class II evidence that treatment with high-dose EPO is not an effective treatment in patients with moderately advanced progressive MS....

  5. Is erythropoietin gene a modifier factor in amyotrophic lateral sclerosis?

    Science.gov (United States)

    Ghezzi, Serena; Del Bo, Roberto; Scarlato, Marina; Nardini, Martina; Carlesi, Cecilia; Prelle, Alessandro; Corti, Stefania; Mancuso, Michelangelo; Briani, Chiara; Siciliano, Gabriele; Murri, Luigi; Bresolin, Nereo; Comi, Giacomo Pietro

    2009-05-01

    To investigate the role of erythropoietin (EPO) as genetic determinant in the susceptibility to sporadic amyotrophic lateral sclerosis (SALS). We sequenced a 259-bp region spanning the 3'hypoxia-responsive element of the EPO gene in 222 Italian SALS patients and 204 healthy subjects, matched for age and ethnic origin. No potentially causative variation was detected in SALS subjects; in addition, two polymorphic variants (namely C3434T and G3544T) showed the same genotype and haplotype frequencies in patients and controls. Conversely, a weak but significant association between G3544T and age of disease onset was observed (p=0.04). Overall, our data argue against the hypothesis of EPO as a genetic risk factor for motor neuron dysfunction, at least in Italian population. However, further studies on larger cohort of patients are needed to confirm the evidence of EPO gene as modifier factor.

  6. Effect of erythropoietin on acoustically traumatized rat cochlea: an immunohistochemical study.

    Science.gov (United States)

    Gürgen, Oğuzhan; Gürgen, Seren Gülşen; Kirkim, Günay; Kolatan, Efsun; Gürkan, Selhan; Güvenç, Yeşim; Eskiizmir, Görkem

    2014-08-01

    To investigate the audiological and histopathological effects of erythropoietin on acoustic overstimulation in rats. Twenty-two male Wistar albino rats were divided into 3 groups: sham group (n = 7), erythropoietin injection group (n = 8), and saline injection group (n = 7). Both erythropoietin and saline injection groups were exposed to white noise (100 decibel [dB] sound pressure level [SPL]) for 3 hours. Auditory brainstem responses were measured before, immediately after, and on the 7th day of noise exposure. All animals were sacrificed on the 7th day and temporal bones were collected. The serial sections of the cochleae were stained by caspase-3 and caspase-9 immunostaining and by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method in order to detect apoptotic cells. In the saline group statistically significant differences were detected between the baseline and immediate postacoustic overstimulation thresholds of click and 6 kHz stimuli. However, when the baseline and immediate postacoustic overstimulation thresholds of click and 6 kHz stimuli were compared in the erythropoietin injection group, no statistically significant difference was determined. Histopathologic evaluations demonstrated that erythropoietin decreased the amount of apoptotic cells in the cochlea. Erythropoietin is likely to prevent the acute threshold changes and decrease the amount of apoptosis in cochlea after acoustic overstimulation in rats.

  7. Blood leptin levels and erythropoietin requirement in Iranian hemodialysis patients

    Directory of Open Access Journals (Sweden)

    Rahimi A

    2008-12-01

    Full Text Available "nBackground: Anemia is a common complication accompanied by high morbidity and mortality in hemodialysis patients. Considering the fact that the reduction of erythropoietin (EPO synthesis is the main cause of uremic anemia, receiving recombinant human erythropoietin (rHuEPO can improve the condition in these patients. Some of these hemodialysis patients, however, have acceptable hemoglobin levels without any need to EPO. Higher BMI, higher albumin and leptin plasma levels and longer durations of hemodialysis are possible factors contributing to the reduced need for rHuEPO in these patients. The present study is designed to asses the relationship between the plasma levels of leptin and the reduced EPO need. "nMethods: Fifty eligible hemodialysis patients with hemoglobin levels higher than 11 mg/dl were enrolled in the cross-sectional study. The information on age, sex, hemodialysis duration and the cause of renal dysfunction were extracted from the files. The baseline plasma levels of Leptin and albumin were measured. The patients BMI and the weekly need for rHuEPO were also calculated. "nResults: There was no correlation between the weekly need for rHuEPO and sex, BMI, the cause of renal dysfunction and the plasma levels of albumin and leptin; it, however, was related with age and the duration of dialysis. While age negatively influences the weekly need, the duration of dialysis has a positive effect on the need. "nConclusion: The plasma levels of leptin are not directly correlated with the required amounts of rHuEPO, indicating that leptin is not an effective factor in erythropoiesis. Conversely, older age and shorter hemodialysis durations are accompanied by reduced need for rHuEPO.

  8. 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.

  9. Preschool Assessment of Preterm Infants Treated With Darbepoetin and Erythropoietin.

    Science.gov (United States)

    Ohls, Robin K; Cannon, Daniel C; Phillips, John; Caprihan, Arvind; Patel, Shrena; Winter, Sarah; Steffen, Michael; Yeo, Ronald A; Campbell, Richard; Wiedmeier, Susan; Baker, Shawna; Gonzales, Sean; Lowe, Jean

    2016-03-01

    We previously reported improved neurodevelopmental outcomes at 2 years among infants treated with the erythropoiesis-stimulating agents (ESAs) darbepoetin alfa (darbepoetin) or erythropoietin. Here we characterize 4-year outcomes. Former preterm infants randomly assigned to receive darbepoetin (10 μg/kg, once per week), erythropoietin (400 U/kg, 3 times/week), or placebo through 35 weeks' postconceptual age were evaluated at 3.5 to 4 years of age. For comparison, healthy children formerly delivered full term (term controls [TCs]) were also recruited. All participants were assessed by using measures of full-scale IQ (FSIQ) and general language from the Wechsler Preschool and Primary Scale of Intelligence, Third Edition, and an overall measure of executive function, on the basis of tests evaluating inhibitory control and spatial working memory. Rates of neurodevelopmental impairment were compared across groups. Multivariate analysis of variance compared children randomly assigned to ESAs (n = 39), placebo (n =14), and TCs (n = 24). FSIQ and performance IQ were significantly higher in the ESA group than in the placebo group (FSIQ: 91.1 ± 17.5 vs 79.2 ± 18.5, P = .036; performance IQ: 93.0 ± 17.0 vs 79.5 ± 19.5, P = .018). Follow-up analyses revealed that the children receiving ESAs performed better than those who received placebo on executive function tasks. The ESA group's performance was below that of TCs, but the results did not reach significance on executive function. The incidence of neurodevelopmental impairment was greater in the placebo group than in the ESA group. ESA-treated infants had better cognitive outcomes and less developmental impairment at 3.5 to 4 years of age compared with placebo-treated infants. ESAs show promise in improving long-term cognitive outcomes of infants born prematurely. Copyright © 2016 by the American Academy of Pediatrics.

  10. CLINICAL APPLICATION OF RECOMBINANT ERYTHROPOIETIN IN BETA-THALASSAEMIA INTERMEDIA.

    Science.gov (United States)

    Asadov, Ch; Alimirzoyeva, Z; Hasanova, M; Mammadova, T; Shirinova, A

    2016-06-01

    Research objective is to study the efficacy of recombinant erythropoietin (epoetin alfa) as alternative method of treatment beta-thalassemia intermedia. Study involved 58 patients with beta-thalassemia intermedia (23 women and 35 men). In all observed patients was defined levels of hemoglobin (Hb), red blood cells (RBC), erythrocyte indexes (MCV, MCH, MCHC), hemoglobin fractions (HbA, HbA2, HbF), serum ferritin, serum erythropoietin before and after administrated rEPO. All patients received rEPO during 6 month at the dose - 10000 IU subcutaneously. The majority of patients - 39 (67%) had a good response to rEPO (increase in hemoglobin level more than 20 g/l); 16 patients (28%) had a mean response (increase in Hb 10 - 20 g/l); in 3 (5%) patients occurred poor response to rEPO therapy (increase in Hb intermedia patients there was a statistically significant change in the number of RBC, levels of HbF and sEPO. The evaluation of interdependence between the indices of the baseline sEPO and increased Hb values in patients after rEPO treatment revealed the presence of the reverse direct relationship (r=-0.67). Based on the results, it can be concluded that the use of rEPO in complex therapy of beta-thalassemia intermedia leads to increased levels of Hb and consequently reducing the need for blood transfusions, and accordingly expected to prevent severe complications of blood transfusion (alloimmunization, hypersplenism, iron overload, contamination transmissible infections) facilitating normal growth and development, and a better quality of life.

  11. Chronic inhibition of tumor cell-derived VEGF enhances the malignant phenotype of colorectal cancer cells

    International Nuclear Information System (INIS)

    Yamagishi, Naoko; Teshima-Kondo, Shigetada; Masuda, Kiyoshi; Nishida, Kensei; Kuwano, Yuki; Dang, Duyen T; Dang, Long H; Nikawa, Takeshi; Rokutan, Kazuhito

    2013-01-01

    Vascular endothelial growth factor-a (VEGF)-targeted therapies have become an important treatment for a number of human malignancies. The VEGF inhibitors are actually effective in several types of cancers, however, the benefits are transiently, and the vast majority of patients who initially respond to the therapies will develop resistance. One of possible mechanisms for the acquired resistance may be the direct effect(s) of VEGF inhibitors on tumor cells expressing VEGF receptors (VEGFR). Thus, we investigated here the direct effect of chronic VEGF inhibition on phenotype changes in human colorectal cancer (CRC) cells. To chronically inhibit cancer cell-derived VEGF, human CRC cell lines (HCT116 and RKO) were chronically exposed (2 months) to an anti-VEGF monoclonal antibody (mAb) or were disrupted the Vegf gene (VEGF-KO). Effects of VEGF family members were blocked by treatment with a VEGF receptor tyrosine kinase inhibitor (VEGFR-TKI). Hypoxia-induced apoptosis under VEGF inhibited conditions was measured by TUNEL assay. Spheroid formation ability was assessed using a 3-D spheroid cell culture system. Chronic inhibition of secreted/extracellular VEGF by an anti-VEGF mAb redundantly increased VEGF family member (PlGF, VEGFR1 and VEGFR2), induced a resistance to hypoxia-induced apoptosis, and increased spheroid formation ability. This apoptotic resistance was partially abrogated by a VEGFR-TKI, which blocked the compensate pathway consisted of VEGF family members, or by knockdown of Vegf mRNA, which inhibited intracellular function(s) of all Vegf gene products. Interestingly, chronic and complete depletion of all Vegf gene products by Vegf gene knockout further augmented these phenotypes in the compensate pathway-independent manner. These accelerated phenotypes were significantly suppressed by knockdown of hypoxia-inducible factor-1α that was up-regulated in the VEGF-KO cell lines. Our findings suggest that chronic inhibition of tumor cell-derived VEGF

  12. VEGF Correlates with Inflammation and Fibrosis in Tuberculous Pleural Effusion

    Science.gov (United States)

    Bien, Mauo-Ying; Wu, Ming-Ping; Chen, Wei-Lin; Chung, Chi-Li

    2015-01-01

    Objective. To investigate the relationship among angiogenic cytokines, inflammatory markers, and fibrinolytic activity in tuberculous pleural effusion (TBPE) and their clinical importance. Methods. Forty-two patients diagnosed with TBPE were studied. Based on chest ultrasonography, there were 26 loculated and 16 nonloculated TBPE patients. The effusion size radiological scores and effusion vascular endothelial growth factor (VEGF), interleukin- (IL-) 8, plasminogen activator inhibitor type-1 (PAI-1), and tissue type plasminogen activator (tPA) were measured. Treatment outcome and pleural fibrosis, defined as radiological residual pleural thickening (RPT), were assessed at 6-month follow-up. Results. The effusion size and effusion lactate dehydrogenase (LDH), VEGF, IL-8, PAI-1, and PAI-1/tPA ratio were significantly higher, while effusion glucose, pH value, and tPA were significantly lower, in loculated than in nonloculated TBPE. VEGF and IL-8 correlated positively with LDH and PAI-1/tPA ratio and negatively with tPA in both loculated and nonloculated TBPE. Patients with higher VEGF or greater effusion size were prone to develop RPT (n = 14; VEGF, odds ratio 1.28, P = 0.01; effusion size, odds ratio 1.01, P = 0.02), and VEGF was an independent predictor of RPT in TBPE (receiver operating characteristic curve AUC = 0.985, P Effusion VEGF correlates with pleural inflammation and fibrosis and may be targeted for adjunct therapy for TBPE. PMID:25884029

  13. VEGF Correlates with Inflammation and Fibrosis in Tuberculous Pleural Effusion

    Directory of Open Access Journals (Sweden)

    Mauo-Ying Bien

    2015-01-01

    Full Text Available Objective. To investigate the relationship among angiogenic cytokines, inflammatory markers, and fibrinolytic activity in tuberculous pleural effusion (TBPE and their clinical importance. Methods. Forty-two patients diagnosed with TBPE were studied. Based on chest ultrasonography, there were 26 loculated and 16 nonloculated TBPE patients. The effusion size radiological scores and effusion vascular endothelial growth factor (VEGF, interleukin- (IL- 8, plasminogen activator inhibitor type-1 (PAI-1, and tissue type plasminogen activator (tPA were measured. Treatment outcome and pleural fibrosis, defined as radiological residual pleural thickening (RPT, were assessed at 6-month follow-up. Results. The effusion size and effusion lactate dehydrogenase (LDH, VEGF, IL-8, PAI-1, and PAI-1/tPA ratio were significantly higher, while effusion glucose, pH value, and tPA were significantly lower, in loculated than in nonloculated TBPE. VEGF and IL-8 correlated positively with LDH and PAI-1/tPA ratio and negatively with tPA in both loculated and nonloculated TBPE. Patients with higher VEGF or greater effusion size were prone to develop RPT (n=14; VEGF, odds ratio 1.28, P=0.01; effusion size, odds ratio 1.01, P=0.02, and VEGF was an independent predictor of RPT in TBPE (receiver operating characteristic curve AUC=0.985, P<0.001. Conclusions. Effusion VEGF correlates with pleural inflammation and fibrosis and may be targeted for adjunct therapy for TBPE.

  14. VEGF correlates with inflammation and fibrosis in tuberculous pleural effusion.

    Science.gov (United States)

    Bien, Mauo-Ying; Wu, Ming-Ping; Chen, Wei-Lin; Chung, Chi-Li

    2015-01-01

    To investigate the relationship among angiogenic cytokines, inflammatory markers, and fibrinolytic activity in tuberculous pleural effusion (TBPE) and their clinical importance. Forty-two patients diagnosed with TBPE were studied. Based on chest ultrasonography, there were 26 loculated and 16 nonloculated TBPE patients. The effusion size radiological scores and effusion vascular endothelial growth factor (VEGF), interleukin- (IL-) 8, plasminogen activator inhibitor type-1 (PAI-1), and tissue type plasminogen activator (tPA) were measured. Treatment outcome and pleural fibrosis, defined as radiological residual pleural thickening (RPT), were assessed at 6-month follow-up. The effusion size and effusion lactate dehydrogenase (LDH), VEGF, IL-8, PAI-1, and PAI-1/tPA ratio were significantly higher, while effusion glucose, pH value, and tPA were significantly lower, in loculated than in nonloculated TBPE. VEGF and IL-8 correlated positively with LDH and PAI-1/tPA ratio and negatively with tPA in both loculated and nonloculated TBPE. Patients with higher VEGF or greater effusion size were prone to develop RPT (n=14; VEGF, odds ratio 1.28, P=0.01; effusion size, odds ratio 1.01, P=0.02), and VEGF was an independent predictor of RPT in TBPE (receiver operating characteristic curve AUC=0.985, PEffusion VEGF correlates with pleural inflammation and fibrosis and may be targeted for adjunct therapy for TBPE.

  15. Ethanol extract of Portulaca oleracea L. protects against hypoxia-induced neuro damage through modulating endogenous erythropoietin expression.

    Science.gov (United States)

    Wanyin, Wang; Liwei, Dong; Lin, Jia; Hailiang, Xin; Changquan, Ling; Min, Li

    2012-04-01

    In addition to its role in erythropoiesis, erythropoietin is also appreciated for its neuroprotective effects, and it has been suggested for treatment of some ischemic-hypoxic neurovascular diseases. The protective effects of endogenous erythropoietin in the brain give rise to the hypothesis that modulating erythropoietin expression might be a better way for treatment of ischemia-hypoxia neurovascular diseases. We have found that ethanol extract of Portulaca oleracea L. (EEPO) could increase erythropoietin expression in hypoxic mouse brain in our previous study. The present study is to investigate whether EEPO exerts its neuroprotective effects against hypoxia injury through regulating endogenous erythropoietin expression. The results demonstrated that EEPO decreased the serum neuron specific enolase level in hypoxia mice and the activity of caspase-3 in neuron, increased the neuron viability and attenuated the pathological damages caused by the hypoxia condition. Importantly, we also found that EEPO stimulated the endogenous erythropoietin expression at both mRNA and protein levels. Using the conditioned medium containing soluble erythropoietin receptor, we found that the neuroprotective effects of EEPO were dependent, at least partly, on erythropoietin expression. Although EEPO did not affect transcription of hypoxia inducible factor-1α (HIF-1α), it did stabilize expression of HIF-1α. It is concluded that EEPO has neuroprotective effects against hypoxia injury, which is at least partly through stimulating endogenous erythropoietin expression by stabilizing HIF-1α. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Recovery of the Erythropoietin-Sensitive Stem-Cell Population following Total-Body X-Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Byron, J. W. [Paterson Laboratories, Christie Hospital and Holt Radium Institute, Manchester (United Kingdom)

    1968-08-15

    Erythropoietin acts upon haemopoietic stem cells to initiate their differentiation into the erythroid series. This effect may be used in polycythaemic mice to estimate changes in the erythropoietin-sensitive stem-cell population following total-body irradiation (TBR). Generally, single doses of erythropoietin, less than that needed for maximum stem-cell response, are used to estimate changes in the stem-cell population. The validity of results using this test is based upon accepting several assumptions regarding erythropoietin kinetics. These are: (a) the contribution of endogenous erythropoietin is always negligible; (b) the origin of the dose-response curve to erythropoietin alters only because of changes in stem-cell numbers; (c) the proportion of stem cells responding to a given concentration of erythropoietin is independent of stem-cell numbers; (d) the slope of the dose-response curve does not alter; and (e) competition between erythropoietin and other factors for the stem cells remains unchanged. The studies to be reported indicate that some of these assumptions m a y not always be valid. Following 150 rad TBR, changes in erythropoietin dose-response curves were not always due to changes in the size of the stem-cell population, but also due to changes in erythropoietin kinetics. Changes in erythropoietin kinetics could be corrected for by using doses of erythropoietin which at any particular time after TBR gave maximum stem-cell response; through full dose-response studies, the nature of changes in erythropoietin kinetics following TBR could be established. These studies appear to explain discrepancies in results obtained in different laboratories using the erythropoietin test. The effect of 150 rad TBR on the erythropoietin-sensitive stem-cell population is an initial depression within 30 min to 20% of normal followed by a second depression (post-irradiation dip) at about 12 h. Twenty-four hours after TBR there is a recovery to the initial depression. This

  17. Erythropoietin during hypoglycaemia in type 1 diabetes: relation to basal renin-angiotensin system activity and cognitive function

    DEFF Research Database (Denmark)

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

    2009-01-01

    diabetes with high and nine with low activity in RAS were studied. Hypoglycaemia was induced using a standardized insulin-infusion. RESULTS: Overall, erythropoietin concentrations increased during hypoglycaemia. In the high RAS group erythropoietin rose 29% (p=0.032) whereas no significant response...... was observed in the low RAS group (7% increment; p=0.43). Independently, both hypoglycaemia and high RAS activity were associated with higher levels of erythropoietin (p=0.02 and 0.04, respectively). Low plasma erythropoietin at baseline was associated with poorer cognitive performance during hypoglycaemia...

  18. VEGF expression in hepatectomized tumor-bearing mice.

    Science.gov (United States)

    Andrini, L; Blanco, A Fernandez; Inda, A; García, M; Garcia, A; Errecalde, A

    2011-01-01

    The experiments were designed in order to study the VEGF expression in intact (group I), hepatectomized (group II), and hepatectomized-tumor bearing mice (group III) throughout one complete circadian time span. Adult male mice were used for the VEGF expression study. The statistical analysis was performed using analysis of variance (ANOVA). The results showed statistical differences in the VEGF expression between groups I and II, but the most significant differences were found between groups I and III. In conclusion, these expressions have a circadian rhythm in all groups; moreover, in group III, this expression was higher and appeared before than in the others.

  19. Structural and thermal characterization of La5Ca9Cu24O41 thin films grown by pulsed laser deposition on (1 1 0) SrTiO3 substrates

    International Nuclear Information System (INIS)

    Svoukis, E.; Athanasopoulos, G.I.; Altantzis, Th.; Lioutas, Ch.; Martin, R.S.; Revcolevschi, A.; Giapintzakis, J.

    2012-01-01

    In the present study stoichiometric, b-axis oriented La 5 Ca 9 Cu 24 O 41 thin films were grown by pulsed laser deposition on (1 1 0) SrTiO 3 substrates in the temperature range 600–750 °C. High resolution transmission electron microscopy was employed to investigate the growth mechanism and the epitaxial relationship between the SrTiO 3 substrates and the La 5 Ca 9 Cu 24 O 41 films grown at 700 °C. The 3-ω method was used to measure the cross-plane thermal conductivity of La 5 Ca 9 Cu 24 O 41 films in the temperature range 50–350 K. The observed glass-like behavior is attributed to atomic-scale defects, grain boundaries and an interfacial layer formed between film and substrate.

  20. 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.

    Objectives: The vascular endothelial growth factor (VEGF) is one of the most important vascular mitogens, while the angiotensin receptor Tie-2 binds to the angiopoietin and stabilizes newly formed vessels. We therefore wanted to localize VEGF and its receptors VEGF-R1, VEGF-R2 and the Tie-2 recep...

  1. The immunohistochemical expression of endocrine gland-derived-VEGF (EG-VEGF) as a prognostic marker in ovarian cancer.

    Science.gov (United States)

    Bălu, Sevilla; Pirtea, L; Gaje, Puşa; Cîmpean, Anca Maria; Raica, M

    2012-01-01

    Ovarian cancer-related angiogenesis is a complex process orchestrated by many positive and negative regulators. Many growth factors are involved in the development of the tumor-associated vasculature, and from these, endocrine gland-derived vascular endothelial growth factor (EG-VEGF) seems to play a crucial role. EG-VEGF is the first organ-specific angiogenic factor and its effects are restricted to the endothelial cells of the endocrine glands. Although EG-VEGF was detected in both normal and neoplastic ovaries, its clinical significance remains controversial. In the present study, we analyzed 30 patients with epithelial ovarian cancer, and the immunohistochemical expression of EG-VEGF was compared with the conventional clinico-pathological parameters of prognosis. Neoplastic cells of the ovarian carcinoma expressed EG-VEGF in 73.33% of the cases, as a cytoplasmic granular product of reaction. We found a strong correlation between the expression of EG-VEGF at protein level and tumor stage, grade, and microscopic type. The expression of EG-VEGF was found in patients with stage III and IV, but not in stage II. The majority of serous adenocarcinoma, half of the cases with clear cell carcinoma and two cases with endometrioid carcinoma showed definite expression in tumor cells. No positive reaction was found in the cases with mucinous carcinoma. Our results showed that EG-VEGF expression is an indicator not only of the advanced stage, but also of ovarian cancer progression. Based on these data, we concluded that EG-VEGF expression in tumor cells of the epithelial ovarian cancer is a good marker of unfavorable prognosis and could be an attractive therapeutic target in patients with advanced-stage tumors, refractory conventional chemotherapy.

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

    African Journals Online (AJOL)

    User

    2011-05-16

    May 16, 2011 ... was quantified by means of western blot and immunohistochemistry technology. ... Key words: Vascular endothelial growth factor (VEGF), spinal cord injury, ... accordance with the National Institute of Health Guide for the Care.

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

    African Journals Online (AJOL)

    User

    2011-05-16

    May 16, 2011 ... Vascular endothelial growth factor (VEGF), a well known angiogenic factor, has been shown to have direct and/or ... Endogenous repair efforts fail to repair ... Spinal cord injury model preparation and intramedullary spinal.

  4. EG-VEGF: a key endocrine factor in placental development.

    Science.gov (United States)

    Brouillet, Sophie; Hoffmann, Pascale; Feige, Jean-Jacques; Alfaidy, Nadia

    2012-10-01

    Endocrine gland-derived vascular endothelial growth factor (EG-VEGF), also named prokineticin 1, is the canonical member of the prokineticin family. Numerous reports suggest a direct involvement of this peptide in normal and pathological reproductive processes. Recent advances propose EG-VEGF as a key endocrine factor that controls many aspects of placental development and suggest its involvement in the development of preeclampsia (PE), the most threatening pathology of human pregnancy. This review describes the finely tuned action and regulation of EG-VEGF throughout human pregnancy, argues for its clinical relevance as a potential diagnostic marker of the onset of PE, and discusses future research directions for therapeutic targeting of EG-VEGF. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. VEGF-A is increased in exogenous endophthalmitis.

    Science.gov (United States)

    Seamone, Mark E; Lewis, Darrell R; Haidl, Ian D; Gupta, R Rishi; O' Brien, Daniel M; Dickinson, John; Samad, Arif; Marshall, Jean S; Cruess, Alan F

    2017-06-01

    Exogenous endophthalmitis is an ophthalmologic emergency defined by panocular inflammation. Vascular endothelial growth factor A (VEGF-A) contributes to inflammation by promoting chemotaxis of monocytes and granulocytes and by increasing vascular permeability. The purpose of this article is to determine if VEGF-A is elevated in the vitreous samples obtained from individuals with exogenous endophthalmitis. Vitreous samples from individuals with exogenous endophthalmitis (n = 18) were analyzed via Luminex assay and enzyme-linked immunosorbent assay for the cytokines VEGF-A, tumor necrosis factor (TNF), interleukin 6 (IL-6), IL-8 (chemokine [CXCL]-8), IL-1β, IL-10, IL-12p70, IL-33, interferon (IFN)-γ, IFN-α, IFN-β, chemokine ligand (CCL)-3, IL-2, IL-5, IL-15, CXCL-10, CCL-2, IL-1Ra, CCL-5, IL-17, and CCL-11. Vitreous samples obtained at the time of macular hole surgery served as controls (n = 8). Concentrations of VEGF-A were significantly elevated in vitreous samples from individuals with exogenous endophthalmitis compared with macular hole (p exogenous endophthalmitis after cataract surgery (p = 0.001), vitrectomy (p = 0.024), and intravitreal injection (p = 0.012). VEGF-A concentrations were similar in both culture-positive and culture-negative populations (p > 0.05). In a linear regression model, levels of VEGF-A correlated significantly with the chemokine CXCL-8 (p = 0.028). We demonstrate that VEGF-A is potently upregulated in exogenous endophthalmitis. This observation provides a foundation for future studies of targeted VEGF-A blockade in the management of endophthalmitis. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

  6. Expression of Ang-2 and VEGF in the endometriosis

    Directory of Open Access Journals (Sweden)

    Xiao-Li Chen

    2016-01-01

    Full Text Available Objective: To detect the expression of Ang-2 and VEGF in the endometriosis (EMT, and to explore the correlation of Ang-2 and VEGF with the pathogenesis of EMT. Methods: A total of 60 patients with EMT who were confirmed by laparoscopy and admitted in our hospital from August, 2014 to August, 2015 were included in the study and served as the observation group; moreover, 60 women who came for laparoscopy at the same stage were served as the control group. A volume of 5mL morning fasting elbow venous blood in the two groups was extracted, standing in the room temperature for 1h, centrifuged at 3 500 r/min for 20 min. The supernatant was extracted and stored at -70 ℃ for inspection. During the laparoscopy, a volume of 5 mL peritoneal fluid was collected, standing in the room temperature for 1 h, centrifuged at 3 500 r/min for 20 min. The supernatant was extracted and stored at -70 ℃ for inspection. ELISA was used to detect the levels of Ang-2 and VEGF. Results: The levels of Ang-2 and VEGF in the serum and peritoneal fluid in the observation group were significantly higher than those in the control group (P<0.05. The serum Ang-2 level in the severe patients was significantly higher than that in the mild patients, while the comparison of VEGF was not statistically significant. The levels of Ang-2 and VEGF in the peritoneal fluid in the severe patients were significantly higher than those in the mild patients. Conclusions: Ang-2 and VEGF can promote the angiogenesis in EMT patients, and their high expressions in the serum and peritoneal fluid are correlated with the occurrence and development of EMT; therefore, detection of the levels of Ang-2 and VEGF is of great significance in estimating the progression of EMT in the clinic.

  7. Vascular endothelial growth factor (VEGF and prostate pathology

    Directory of Open Access Journals (Sweden)

    Francisco Botelho

    2010-08-01

    Full Text Available PURPOSE: Previous studies suggest that vascular endothelial growth factor (VEGF circulating levels might improve identification of patients with prostate cancer but results are conflicting. Our aim was to compare serum VEGF levels across different prostate pathologies (including benign prostatic hyperplasia, prostatitis, high grade prostate intraepithelial neoplasia and prostate cancer in patients at high risk of prostate cancer. MATERIALS AND METHODS: We consecutively enrolled 186 subjects with abnormal digital rectal examination and/or total PSA (tPSA = 2.5 ng/mL. Blood was collected before diagnostic ultrasound guided trans-rectal prostate biopsy, or any prostate oncology treatment, to measure PSA isoforms and VEGF. Unconditional logistic regression was used to compute age-, tPSA- and free/total PSA-adjusted odds ratios (OR and respective 95% confidence intervals (95% CI for the association between serum VEGF and different prostatic pathologies. RESULTS: Prostate biopsy main diagnoses were normal or benign prostatic hyperplasia (27.3%, prostatitis (16.6%, and prostatic cancer (55.0%. The median VEGF levels (ng/mL in these groups were 178.2, 261.3 and 266.4 (p = 0.029, respectively, but no significant differences were observed for benign vs. malignant pathologies (215.2 vs. 266.4, p = 0.551. No independent association was observed between VEGF (3rd vs. 1st third and prostate cancer, when compared to benign conditions (adjusted OR = 1.44; CI 95%: 0.64-3.26. CONCLUSIONS: In patients at high risk of prostate cancer, circulating VEGF levels have no clinical role in deciding which patients should be submitted to prostate biopsy. Prostatitis patients, often with higher PSA levels, also present high serum levels of VEGF, and their inclusion in control groups might explain the heterogeneous results in previous studies.

  8. 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.

  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. AdVEGF-B186 and AdVEGF-DΔNΔC induce angiogenesis and increase perfusion in porcine myocardium.

    Science.gov (United States)

    Nurro, Jussi; Halonen, Paavo J; Kuivanen, Antti; Tarkia, Miikka; Saraste, Antti; Honkonen, Krista; Lähteenvuo, Johanna; Rissanen, Tuomas T; Knuuti, Juhani; Ylä-Herttuala, Seppo

    2016-11-01

    Coronary heart disease remains a significant clinical problem, and new therapies are needed especially for patients with refractory angina for whom the current therapies do not provide sufficient relief. The aim of this study was to find out if angiogenic gene therapy using new members of the vascular endothelial growth factor (VEGF) family, VEGF-B 186 and VEGF-D ΔNΔC , increase myocardial perfusion as measured by the positron emission tomography (PET) 15 O-imaging, and whether there would be coronary steal effect to the contralateral side. Furthermore, safety of intramyocardial angiogenic adenoviral gene transfer was evaluated. Intramyocardial adenoviral (Ad) VEGF-B 186 or AdVEGF-D ΔNΔC gene transfers were given endovascularly into the porcine posterolateral wall of the left ventricle (n=34). Six days later, PET 15 O-imaging for myocardial perfusion and coronary angiography were performed. AdVEGF-B 186 and AdVEGF-D ΔNΔC induced angiogenesis and increased total microvascular area 1.8-fold (95% CI 0.2 to 3.5) and 2.8-fold (95% CI 1.4 to 4.3), respectively. At rest, perfusion was maintained at normal levels, but at stress, relative perfusion was increased 1.4-fold (95% CI 1.1 to 1.7) for AdVEGF-B 186 and 1.3-fold (95% CI 1.0 to 1.7) for AdVEGF-D ΔNΔC , without causing coronary steal effect in the control area. The therapy was well tolerated and did not lead to any significant changes in laboratory safety parameters. Both AdVEGF-B 186 and AdVEGF-D ΔNΔC gene transfers induced efficient angiogenesis in the myocardium resulting in an increased myocardial perfusion measured by PET. Importantly, local perfusion increase did not induce any coronary steal effect. As such, both treatments seem suitable new candidates for the induction of therapeutic angiogenesis for the treatment of refractory angina. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  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. Increased preoperative collection of autologous blood with recombinant human erythropoietin therapy in tertiary care hospitals of Jammu

    Directory of Open Access Journals (Sweden)

    Kumkum Sharma

    2013-01-01

    Full Text Available Introduction: To study whether the administration of recombinant human erythropoietin increases the amount of autologous blood that can be collected before orthopaedic surgery. Materials and Methods: We conducted a randomized controlled trial of recombinant human erythropoietin in 68 adults scheduled for elective orthopedic procedures. The patients received either erythropoietin 600 units/kg of body weight or placebo intravenously every 5 th day prior to each phlebotomy for 21 days during which time up to 5 units of blood was collected. Patients were excluded from donation when their hematocrit values were less than 33%. All patients received iron sulphate 325mg orally 3 times daily. The mean number of units collected per patient was 4.33 ± 0.4 for erythropoietin group and 3.05± 0.71 for the placebo group. Results: The mean packed red cell volume donated by patients who received erythropoietin was 32% greater than that donated by patients who received placebo (196.3 vs. 169.4 ml, p<0.05. 68% in the placebo group and 9% of patients treated with erythropoietin were unable to donate ≥4 units. No adverse effects were attributed to erythropoietin. While participating in the study, complications developed in 2 patients one in each group necessitating their removal from the study. Conclusion: We conclude that recombinant human erythropoietin increases the ability of the patients about to undergo elective surgery to donate autologous blood units.

  13. 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.

  14. VEGF111b, a new member of VEGFxxxb isoforms and induced by mitomycin C, inhibits angiogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Fang; Li, Xiuli [Department of Obstetrics and Gynecology, Chinese PLA General Hospital, Beijing (China); Kong, Jian [Department of Hepatobiliary Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing (China); Pan, Bing [The Institute of Cardiovascular Sciences, Peking University Health Science Center, Key Laboratory of Molecular Cardiovascular Sciences of Education Ministry, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides of Health Ministry, Beijing (China); Institute of Systems Biomedicine, School of Basic Medical Sciences, Peking University Health Science Center, Key Laboratory of Molecular Cardiovascular Sciences of Education Ministry, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides of Health Ministry, Beijing (China); Sun, Min [Department of Obstetrics and Gynecology, Tangdu Hospital, Fourth Military Medical University, Xian (China); Zheng, Lemin, E-mail: zhengl@bjmu.edu.cn [The Institute of Cardiovascular Sciences, Peking University Health Science Center, Key Laboratory of Molecular Cardiovascular Sciences of Education Ministry, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides of Health Ministry, Beijing (China); Institute of Systems Biomedicine, School of Basic Medical Sciences, Peking University Health Science Center, Key Laboratory of Molecular Cardiovascular Sciences of Education Ministry, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides of Health Ministry, Beijing (China); Yao, Yuanqing, E-mail: yqyao@126.com [Department of Obstetrics and Gynecology, Chinese PLA General Hospital, Beijing (China)

    2013-11-08

    Highlights: •We discovered a new member of VEGFxxxb family-VEGF111b. •We found VEGF111b mRNA and protein can be induced by mitomycin C. •We confirmed VEGF111b over-expression inhibits angiogenesis. •VEGF111b inhibits angiogenesis through inhibiting VEGF-R2/PI3K/Akt and VEGF-R2/ERK1/2 phosphorylation. -- Abstract: Vascular endothelial growth factor (VEGF-A) stimulating angiogenesis is required for tumor growth and progression. The conventional VEGF-A isoforms have been considered as pro-angiogenic factors. Another family of VEGF-A isoforms generated by alternative splicing, termed VEGFxxxb isoforms, has anti-angiogenic property, exemplified by VEGF165b. Here, we identify a new number of VEGFxxx family-VEGF111b induced by mitomycin C, although not detected in mitomycin C-unexposed ovarian cancer cells. SKOV3 cells were transfected with pcDNA{sub 3.1} empty vector, pcDNA{sub 3.1}-VEGF111b or pcDNA{sub 3.1}-VEGF165b to collect conditioned mediums respectively. VEGF111b overexpression inhibits proliferation, migration and tube formation of endothelial cell by inhibiting VEGF-R2 phosphorylation and its downstream signaling, similar to VEGF165b but slightly lower than VEGF165b. The anti-angiogenic property depends on the six amino acids of exon 8b of the VEGFxxxb isoforms. Our results show that VEGF111b is a novel potent anti-angiogenic agent that can target the VEGF-R2 and its signaling pathway to inhibit ovarian tumor growth.

  15. VEGF111b, a new member of VEGFxxxb isoforms and induced by mitomycin C, inhibits angiogenesis

    International Nuclear Information System (INIS)

    Gu, Fang; Li, Xiuli; Kong, Jian; Pan, Bing; Sun, Min; Zheng, Lemin; Yao, Yuanqing

    2013-01-01

    Highlights: •We discovered a new member of VEGFxxxb family-VEGF111b. •We found VEGF111b mRNA and protein can be induced by mitomycin C. •We confirmed VEGF111b over-expression inhibits angiogenesis. •VEGF111b inhibits angiogenesis through inhibiting VEGF-R2/PI3K/Akt and VEGF-R2/ERK1/2 phosphorylation. -- Abstract: Vascular endothelial growth factor (VEGF-A) stimulating angiogenesis is required for tumor growth and progression. The conventional VEGF-A isoforms have been considered as pro-angiogenic factors. Another family of VEGF-A isoforms generated by alternative splicing, termed VEGFxxxb isoforms, has anti-angiogenic property, exemplified by VEGF165b. Here, we identify a new number of VEGFxxx family-VEGF111b induced by mitomycin C, although not detected in mitomycin C-unexposed ovarian cancer cells. SKOV3 cells were transfected with pcDNA 3.1 empty vector, pcDNA 3.1 -VEGF111b or pcDNA 3.1 -VEGF165b to collect conditioned mediums respectively. VEGF111b overexpression inhibits proliferation, migration and tube formation of endothelial cell by inhibiting VEGF-R2 phosphorylation and its downstream signaling, similar to VEGF165b but slightly lower than VEGF165b. The anti-angiogenic property depends on the six amino acids of exon 8b of the VEGFxxxb isoforms. Our results show that VEGF111b is a novel potent anti-angiogenic agent that can target the VEGF-R2 and its signaling pathway to inhibit ovarian tumor growth

  16. Clinical applications of measurement of serum immunoreactive levels of erythropoietin

    International Nuclear Information System (INIS)

    Miller, M.E.; Chandra, M.; Garcia, J.F.

    1985-01-01

    The purification of erythropoietin (Ep) in 1977 enabled investigators to more clearly define the role of this hormone in erythropoiesis in man. Radioimmunoassays were rapidly developed. Undoubtedly differences between levels of immunoreactive and biologically active Ep will be found but the resolution of these discrepancies will expand our understanding of the erythron. Recently others described a monoclonal antibody against Ep. Because of this breakthrough, large quantities of pure hormone should soon be available to a larger number of investigators than currently have access to it. The major clinical use of this hormone will probably be in the treatment of the anemia of chronic renal disease. In the relatively few years since the radioimmunoassay (RIA) was developed, measurements of the levels of this hormone have been made in several disease states as well as in normal man. Most of the findings to date confirm the predictions that have been made over the years based on studies done using the rather crude bioassay for Ep. In the present study the authors shall review and expand on what is known about subjects with chronic lung and renal disease

  17. Antioxidants may Attenuate Plasma Erythropoietin Decline after Hyperbaric Oxygen Diving.

    Science.gov (United States)

    Mutzbauer, T S; Schneider, M; Neubauer, B; Weiss, M; Tetzlaff, K

    2015-11-01

    According to previous studies, plasma erythropoietin (EPO) may decrease after hyperbaric oxygen exposure due to oxidative stress. It is hypothesized that the decrease of EPO can be attenuated by oxygen free radical scavengers.The aim of the present study was to evaluate whether EPO plasma levels can be influenced by oral application of vitamin C and E before repeated hyperbaric oxygen exposure during diving. 16 healthy male police task force divers performed 3 morning dives on oxygen within a regular diving schedule on 3 consecutive days. They were randomized into either the placebo group or the vitamin group, receiving 1 g ascorbic acid and 600 IU D-α-tocopherol orally 60 min before the dive. Blood samples for EPO measurement were taken on days 1, 2, and 3 at T1, T3 and T5 60 min before and at T2, T4 and T6 60 min after each dive, respectively. A moderate decrease of EPO was observed beginning at T3 until T6 in the placebo group. The EPO concentrations in the vitamin group did not show relevant variations compared to baseline. Radical scavenging vitamins C and D may counteract hyperbaric oxygen related mechanisms reducing EPO production in hyperbaric oxygen exposure during diving. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Stability of erythropoietin repackaging in polypropylene syringes for clinical use

    Directory of Open Access Journals (Sweden)

    Angela Marsili

    2017-02-01

    Full Text Available Introduction: Epoetin alfa (Eprex® is a subcutaneous, injectable formulation of short half-life recombinant human erythropoietin (rHuEPO. To current knowledge there are no published studies regarding the stability of rHuEPO once repackaging occurs (r-EPO for clinical trial purposes. Materials and methods: We assessed EPO concentration in Eprex® and r-EPO syringes at 0, 60, 90, and 120 days after repackaging in polypropylene syringes. R-EPO was administered to 56 patients taking part in a clinical trial in Friedreich Ataxia. Serum EPO levels were measured at baseline and 48 h after r-EPO administration. Results: No differences were found between r-EPO and Eprex® syringes, but both globally decreased in total EPO content during storage at 4 °C. Patients receiving r-EPO had similar levels in EPO content as expected from previous trials in Friedreich Ataxia and from pharmacokinetics studies in healthy volunteers. Discussion: We demonstrate that repackaging of EPO does not alter its concentration if compared to the original product (Eprex®. This is true both for repackaging procedures and for the stability in polypropylene tubes. The expiration date of r-EPO can be extended from 1 to 4 months after repackaging, in accordance with pharmacopeia rules.

  19. 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.

  20. Endogenous erythropoietin protects neuroretinal function in ischemic retinopathy.

    Science.gov (United States)

    Mowat, Freya M; Gonzalez, Francisco; Luhmann, Ulrich F O; Lange, Clemens A; Duran, Yanai; Smith, Alexander J; Maxwell, Patrick H; Ali, Robin R; Bainbridge, James W B

    2012-04-01

    Because retinal ischemia is a common cause of vision loss, we sought to determine the effects of ischemia on neuroretinal function and survival in murine oxygen-induced retinopathy (OIR) and to define the role of endogenous erythropoietin (EPO) in this model. OIR is a reproducible model of ischemia-induced retinal neovascularization; it is used commonly to develop antiangiogenic strategies. We investigated the effects of ischemia in murine OIR on retinal function and neurodegeneration by electroretinography and detailed morphology. OIR was associated with significant neuroretinal dysfunction, with reduced photopic and scotopic ERG responses and reduced b-wave/a-wave ratios consistent with specific inner-retinal dysfunction. OIR resulted in significantly increased apoptosis and atrophy of the inner retina in areas of ischemia. EPO deficiency in heterozygous Epo-Tag transgenic mice was associated with more profound retinal dysfunction after OIR, indicated by a significantly greater suppression of ERG amplitudes, but had no measurable effect on the extent of retinal ischemia, preretinal neovascularization, or neuroretinal degeneration in OIR. Systemic administration of recombinant EPO protected EPO-deficient mice against this additional suppression, but EPO supplementation in wild-type animals with OIR did not rescue neuroretinal dysfunction or degeneration. Murine OIR offers a valuable model of ischemic neuroretinal dysfunction and degeneration in which to investigate adaptive tissue responses and evaluate novel therapeutic approaches. Endogenous EPO can protect neuroretinal function in ischemic retinopathy. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  1. Erythropoietin enhances hippocampal long-term potentiation and memory

    Directory of Open Access Journals (Sweden)

    El-Kordi Ahmed

    2008-09-01

    Full Text Available Abstract Background Erythropoietin (EPO improves cognition of human subjects in the clinical setting by as yet unknown mechanisms. We developed a mouse model of robust cognitive improvement by EPO to obtain the first clues of how EPO influences cognition, and how it may act on hippocampal neurons to modulate plasticity. Results We show here that a 3-week treatment of young mice with EPO enhances long-term potentiation (LTP, a cellular correlate of learning processes in the CA1 region of the hippocampus. This treatment concomitantly alters short-term synaptic plasticity and synaptic transmission, shifting the balance of excitatory and inhibitory activity. These effects are accompanied by an improvement of hippocampus dependent memory, persisting for 3 weeks after termination of EPO injections, and are independent of changes in hematocrit. Networks of EPO-treated primary hippocampal neurons develop lower overall spiking activity but enhanced bursting in discrete neuronal assemblies. At the level of developing single neurons, EPO treatment reduces the typical increase in excitatory synaptic transmission without changing the number of synaptic boutons, consistent with prolonged functional silencing of synapses. Conclusion We conclude that EPO improves hippocampus dependent memory by modulating plasticity, synaptic connectivity and activity of memory-related neuronal networks. These mechanisms of action of EPO have to be further exploited for treating neuropsychiatric diseases.

  2. 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

    in 2, 3 diphosphoglycerate. After 64 h at altitude, six of the nine subjects had down-regulated their serum-EPO concentrations so that median values were three times above those at sea level. These six subjects had significant diurnal variations of serum-EPO concentration at sea level; the nadir......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 level...... and during 4 days at an altitude of 4350 m. Median sea level serum-EPO concentration was 6 (range 6-13) U.l-1. Serum-EPO concentration increased after 18 and 42 h at altitude, [58 (range 39-240) and 54 (range 36-340) U.l-1, respectively], and then decreased after 64 and 88 h at altitude [34 (range 18...

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

    International Nuclear Information System (INIS)

    Feder, D.; Rugollini, M.; Santomauro, A. Jr; Oliveira, L.P.; Lioi, V.P.; Santos, R. dos; Ferreira, L.G.; Nunes, M.T.; Carvalho, M.H.; Delgado, P.O.; Carvalho, A.A.S.; Fonseca, F.L.A.

    2014-01-01

    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

  4. Modulation of erythropoietin concentrations by manipulation of hypercarbia

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M.E.; Howard, D.

    1979-01-01

    The present studies were done to determine whether preventing the respiratory alkalosis, which is known to occur with acute hypoxic stimuli, would lead to alterations in plasma concentrations of erythropoietin (Ep). Rats were subjected to two acute stresses, hypoxia and blood loss, separately and in combination, with and without the added stress of hypercarbia. Hypercarbia in all experimental groups was associated with a decrease in plasma concentrations of Ep. This reduction in plasma Ep with hypercarbia could not be fully explained by the higher arterial pO/sub 2/s or p50s of the hypercarbic rats. Hypercarbia may have indirectly suppressed Ep production by increasing blood flow to the site of Ep production. Alternatively, the cell of origin of Ep could be sensitive to changes in pH and/or pCO/sub 2/. It was further demonstrated that neither the onset nor the degree of reticulocytosis could be predicted by the plasma Ep concentrations. It is likely that the removal of red blood cells led to a decrease in marrow transit time with the early emergence of reticulocytes after acute blood loss.

  5. Radioimmunoassay of erythropoietin: analytical performance and clinical use in hematology.

    Science.gov (United States)

    Schlageter, M H; Toubert, M E; Podgorniak, M P; Najean, Y

    1990-10-01

    We report here the performance of a recently commercialized radioimmunoassay kit for determining erythropoietin (EPO) in serum or plasma. The lower detection limit of the method was 3 U/L. Precision, analyzed by the variation coefficients between different assay runs and in the same experiment, was always less than 10%; accuracy was assessed by recovery and dilution tests. In anemic patients (hematocrit 18-39%), the concentration of EPO was logarithmically related to hematocrit. A relatively large dispersion of the results was noted, as reported by others with various RIAs. Patients with severe renal failure demonstrated a very low EPO value, whatever the degree of their anemia. In some chronic anemias resulting from malignancy, EPO concentrations were also relatively low. In the polycythemia vera group, the EPO mean was below normal for greater than 95% of the patients, whatever their clinical stage (first evaluation, relapse, or remission). In contrast, 91% of the patients with pure erythrocytosis had a normal or increased EPO value, even when the etiology was unknown. Measurement of EPO concentration may be useful for the clinical differentiation of myeloproliferative disorders and, subsequently, for their prognosis and choice of treatment.

  6. Functional significance of erythropoietin in renal cell carcinoma

    International Nuclear Information System (INIS)

    Morais, Christudas; Johnson, David W; Vesey, David A; Gobe, Glenda C

    2013-01-01

    One of the molecules regulated by the transcription factor, hypoxia inducible factor (HIF), is the hypoxia-responsive hematopoietic factor, erythropoietin (EPO). This may have relevance to the development of renal cell carcinoma (RCC), where mutations of the von Hippel-Lindau (VHL) gene are major risk factors for the development of familial and sporadic RCC. VHL mutations up-regulate and stabilize HIF, which in turn activates many downstream molecules, including EPO, that are known to promote angiogenesis, drug resistance, proliferation and progression of solid tumours. HIFs typically respond to hypoxic cellular environment. While the hypoxic microenvironment plays a critical role in the development and progression of tumours in general, it is of special significance in the case of RCC because of the link between VHL, HIF and EPO. EPO and its receptor, EPOR, are expressed in many cancers, including RCC. This limits the use of recombinant human EPO (rhEPO) to treat anaemia in cancer patients, because the rhEPO may be stimulatory to the cancer. EPO may also stimulate epithelial-mesenchymal transition (EMT) in RCC, and pathological EMT has a key role in cancer progression. In this mini review, we summarize the current knowledge of the role of EPO in RCC. The available data, either for or against the use of EPO in RCC patients, are equivocal and insufficient to draw a definitive conclusion

  7. 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.

  8. Recombinant human erythropoietin therapy in critically ill Jehovah's Witnesses.

    Science.gov (United States)

    Ball, Amanda M; Winstead, P Shane

    2008-11-01

    Blood transfusions and blood products are often given as a life-saving measure in patients with critical illness. However, some patients, such as Jehovah's Witnesses, may refuse their administration due to religious beliefs. Jehovah's Witnesses accept most available medical treatments, but not blood transfusions or blood products due to their religion's interpretation of several passages from the Bible. Since recombinant human erythropoietin (rHuEPO) became available, several cases have been reported in which rHuEPO was successfully administered to critically ill Jehovah's Witnesses. Administration of rHuEPO in combination with other blood conservation techniques has been shown to increase hemoglobin levels and survival in patients who experienced trauma, burns, general surgery, or gastrointestinal hemorrhage. We performed a literature search of the MEDLINE and International Pharmaceutical Abstracts databases of rHuEPO therapy in the Jehovah's Witness population. Fourteen cases were identified in which rHuEPO was administered to Jehovah's Witnesses who required the drug for critical care resuscitation as an alternative to blood products. In each clinical situation, rHuEPO enhanced erythropoiesis; however, time to the start of treatment, dosages, route of administration, and treatment duration varied widely. Supplementation with adjunctive agents, such as iron, folic acid, and vitamin B12, was also beneficial. Use of rHuEPO in Jehovah's Witnesses may provide an alternative to blood transfusions or blood products. Other alternatives, such as hemoglobin-based oxygen carriers and perfluorocarbons, are also being explored.

  9. 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...... were unchanged. The conclude that, in spite of changes in rheologic variables, increasing viscosity of the blood and thus possibly increasing the peripheral resistance, these had no effect on the cardiovascular state. Erythropoietin treatment improves the subjective well-being in patients on chronic...

  10. Erythropoietin between therapy and doping : Two sides of the same coin

    Directory of Open Access Journals (Sweden)

    Ostojić Ana

    2016-01-01

    Full Text Available Erythropoietin is a hormone that promotes the formation of red blood cells by the bone marrow. In adults it is mainly produced by the kidneys as a response to hypoxia. Besides its main role, it also acts as antiapoptotic, anti-inflammatory and cytoprotective agent. Furthermore, it is produced in many non-hematopoietic tissues where it acts locally, stimulating angiogenesis. Erythropoietin binds cytokine receptors on target cells, such as erythrocyte precursor cells, neurons, glial and endothelial cells, cardiomyocytes, myocytes etc. The discovery of synthetic erythropoietin forms, in the late eighties of the last century, has significantly improved treatment outcome of patients with anaemia related to chronic diseases, especially chronic renal failure. Renal anaemia is multifactorial, but predominantly a consequence of erythropoietin deficiency. Today, three generations of erythropoiesis stimulating agents are available, differing in glycosylation pattern, molecular size, half-life and modes of administration and dosage. In anaemic patients this therapy significantly improves their quality of life, but may also have serious, potentially dangerous adverse effects. Synthesis of recombinant human erythropoietin, on the other hand, has improved possibilities for manipulations in sport, in the field of blood doping. Erythropoietin administration in athletes increases their maximum oxygen consumption capacity, improves endurance and performance, especially in aerobic exercise. This seriously undermines the spirit of sport, and also endangers athletes' health. Different anti-doping tests have been developed and used, still with limited success. At the same time, new illicit ways of malpractice are developing, such as variuos models of gene doping. Therefore, providing new models of anti-doping tests and strategies, together with better health control of athletes, still remains a considerable challenge.

  11. Caveat oncologist: clinical findings and consequences of distributing counterfeit erythropoietin in the United States.

    Science.gov (United States)

    Qureshi, Zaina P; Norris, Leann; Sartor, Oliver; McKoy, June M; Armstrong, John; Raisch, Dennis W; Garg, Vishvas; Stafkey-Mailey, Dana; Bennett, Charles Lee

    2012-03-01

    Counterfeit pharmaceuticals pose risks domestically. Because of their cost, cancer pharmaceuticals are vulnerable. We review findings from a domestic counterfeiting episode involving erythropoietin and outline anticounterfeiting recommendations for policy makers, patients, and health care professionals. Information was obtained on patients who received counterfeit erythropoietin, its distribution, and criminal investigations into counterfeiting networks. Interview sources included a physician, an attorney, employees of the Florida Department of Health and Human Services and the US Food and Drug Administration's (FDA) Office of Criminal Investigation, manufacturers, and wholesalers. Other sources included the book "Dangerous Doses," LexisNexis (search terms "counterfeit" and "erythropoietin") and the FDA database. Counterfeit product consisted of 2,000 U vials with counterfeit labels denoting 40,000 U. The counterfeiters, in collaboration with a Miami pharmacy, purchased 110,000 erythropoietin 2,000 U vials and affixed counterfeit labels to each vial. Products were then sold via the pharmaceutical "gray market" to wholesalers, then pharmacy chains. Investigations by Florida government officials implicated 17 persons, all of whom were found guilty of trafficking in counterfeit pharmaceuticals. Despite the large size of the operation, the FDA received reports of only 12 patients who had received counterfeit erythropoietin and detailed information for only two individuals. A 17-year-old liver transplant recipient and a 61-year-old patient with breast cancer experienced loss of efficacy after receiving counterfeit erythropoietin. Wider use of FDA anticounterfeit initiatives, limiting pharmaceutical suppliers to reputable distributors, and educating providers and patients about signs of counterfeit drugs can improve the safety of cancer pharmaceuticals.

  12. FGF23 modulates the effects of erythropoietin on gene expression in renal epithelial cells

    Directory of Open Access Journals (Sweden)

    Yashiro M

    2018-04-01

    Full Text Available Mitsuru Yashiro,1 Masaki Ohya,1 Toru Mima,1 Yumi Ueda,2 Yuri Nakashima,1 Kazuki Kawakami,1 Yohei Ishizawa,2 Shuto Yamamoto,1 Sou Kobayashi,1 Takurou Yano,1 Yusuke Tanaka,1 Kouji Okuda,1 Tomohiro Sonou,1 Tomohiro Shoshihara,1 Yuko Iwashita,1 Yu Iwashita,1 Kouichi Tatsuta,1 Ryo Matoba,2 Shigeo Negi,1 Takashi Shigematsu1 1Department of Nephrology, Wakayama Medical University, Wakayama, Japan; 2DNA Chip Research Inc., Minato, Japan Background: FGF23 plays an important role in calcium–phosphorus metabolism. Other roles of FGF23 have recently been reported, such as commitment to myocardium enlargement and immunological roles in the spleen. In this study, we aimed to identify the roles of FGF23 in the kidneys other than calcium–phosphorus metabolism. Methods: DNA microarrays and bioinformatics tools were used to analyze gene expression in mIMCD3 mouse renal tubule cells following treatment with FGF23, erythropoietin and/or an inhibitor of ERK. Results: Three protein-coding genes were upregulated and 12 were downregulated in response to FGF23. Following bioinformatics analysis of these genes, PPARγ and STAT3 were identified as candidate transcript factors for mediating their upregulation, and STAT1 as a candidate for mediating their downregulation. Because STAT1 and STAT3 also mediate erythropoietin signaling, we investigated whether FGF23 and erythropoietin might show interactive effects in these cells. Of the 15 genes regulated by FGF23, 11 were upregulated by erythropoietin; 10 of these were downregulated following cotreatment with FGF23. Inhibition of ERK, an intracellular mediator of FGF23, reversed the effects of FGF23. However, FGF23 did not influence STAT1 phosphorylation, suggesting that it impinges on erythropoietin signaling through other mechanisms. Conclusion: Our results suggest cross talk between erythropoietin and FGF23 signaling in the regulation of renal epithelial cells. Keywords: FGF23, STAT1, PPARγ, DNA microarray

  13. 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...

  14. Recombinant Erythropoietin And Blood Transfusion In Very Low Birth Weight Infants

    Directory of Open Access Journals (Sweden)

    Keramat Nouri

    2005-05-01

    Full Text Available Backgroundp: Very low birth weight infants ( <1500 g frequently require blood transfusions because of repeated blood sampling accompanied by anemia of prematurity. Methods: In an attempt to identify the effect of human recombinant erythropoietin to decrease the requirement for blood transfusions, erythropoietin was administered to 24 pre term infants less than 1500 g prospectively from September 1999 till December2000. Data about the characteristics of the population, the severity of diseases, and treatment with erythropoietin, clinical diagnosis, initial and subsequent hemoglobin, volume of blood loss, and the number of blood transfusions were recorded. These results were compared with data from the recorded information of 49 infants who did not receive erythropoietin during those past 2 years. There were no differences between the 2 groups with regard to the gestational age, birth weight, clinical diagnosis, severity of the illness, primary causes of admission, and initial hematologic parameters such as hemoglobin, hematocrit and reticulocytes. Erythropoietin was administered in a dose of 200 ill/kg three times weekly for 6-8 weeks accompanied with iron supplement 6 mg/ kg/day. Transfusions were administered according to protocol. Results: There was no significant difference between the number of blood transfusion among these 2 groups (p= 0.07. However, transfusions in the erythropoietin treated group were fewer in comparison to the other group (1.9 +1-1.6 to 3.2 +/-1.1. No difference was observed between final hemoglobin and hematocrit levels among the two groups (10.3 +1- 0.9 vs. 10.4 +1- 0.7 and 33.7 +1- 2.3 vs. 32.2 +1- 2.2. Conclusion: Very low birth weight infants receive frequent blood transfusions but a reduction in transfusion requirements was not apparent after administration of erythropoietin and iron in preterm infants in this study. However, the lack of impact on transfusion requirements fails to support routine use of

  15. Neural correlates of improved recognition of happy faces after erythropoietin treatment in bipolar disorder

    DEFF Research Database (Denmark)

    Miskowiak, K W; Petersen, N A; Harmer, C J

    2018-01-01

    -group design. Participants underwent whole-brain fMRI at 3T, mood ratings and blood tests at baseline and week 14. During fMRI, participants viewed happy and fearful faces and performed a gender discrimination task. RESULTS: Thirty-four patients had complete pre- and post-treatment fMRI data (EPO: N = 18......, saline: N = 16). Erythropoietin vs. saline increased right superior frontal response to happy vs. fearful faces. This correlated with improved happiness recognition in the EPO group. Erythropoietin also enhanced gender discrimination accuracy for happy faces. These effects were not influenced...

  16. SREBP inhibits VEGF expression in human smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Motoyama, Koka [Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan); Fukumoto, Shinya [Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan); Koyama, Hidenori [Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan); Emoto, Masanori [Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan); Shimano, Hitoshi [Department of Internal Medicine, Institute of Clinical Medicine, University of Tsukuba, Ibaraki (Japan); Maemura, Koji [Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Tokyo (Japan); Nishizawa, Yoshiki [Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka (Japan)

    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.

  17. SREBP inhibits VEGF expression in human smooth muscle cells

    International Nuclear Information System (INIS)

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

    2006-01-01

    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

  18. 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.

  19. Effects of EG-VEGF, VEGF and TGF-β1 on pregnancy outcome in patients undergoing IVF-ET treatment.

    Science.gov (United States)

    Gao, Min-zhi; Zhao, Xiao-ming; Lin, Yi; Sun, Zhao-gui; Zhang, Hui-qin

    2012-10-01

    To investigate the correlation of endocrine gland-derived vascular endothelial growth factor (EG-VEGF), vascular endothelial growth factor (VEGF) and transforming growth factor beta 1 (TGF-β1) with the corresponding reproductive outcome in patients who received in vitro fertilization-embryo transfer (IVF-ET). Sixty-seven women undergoing IVF-ET at a university tertiary hospital were recruited for a prospective study. Concentrations of EG-VEGF, VEGF and TGF-β1 were measured by enzyme-linked immunosorbent assay (ELISA) in follicular fluid (FF) collected during oocyte retrieval (OR) and in serum collected 2 days after OR. In FF, concentrations of both EG-VEGF and VEGF were negatively correlated with peak E2 and the number of MII oocytes retrieved, and positively correlated with each other. In serum, concentrations of all the three growth factors were positively correlated with the rate of good quality embryo, and with one another. Patients in the pregnancy group had lower peak E2 concentrations and higher serum EG-VEGF concentrations than those in the non-pregnancy group, but such tendency was not observed in the case of VEGF and TGF-β1. Both concentrations of EG-VEGF and VEGF in FF were negatively correlated with ovarian response and oocyte maturation. Concentrations of all the three growth factors in serum were positively correlated with embryo quality, but only serum concentrations of EG-VEGF were associated with the pregnancy outcome.

  20. Applications and biomonitoring issues of recombinant erythropoietins for doping control.

    Science.gov (United States)

    Tsitsimpikou, Christina; Kouretas, Demetrios; Tsarouhas, Konstantinos; Fitch, Kenneth; Spandidos, Demetrios A; Tsatsakis, Aristides

    2011-02-01

    The biochemical actions and side effects of recombinant erythropoietins (rhEPOs), their analogs and mimetics, their misuse as doping agents, and the principal analytical strategies developed to identify them in athletes' biologic fluids are reviewed. Patients who experience a range of pathologies have benefited from the administration of rhEPOs to correct severe anemia. Currently, monitoring the biologic effect of rhEPO in patients under treatment is by measuring the hemoglobin concentration. However, it may be valuable to directly monitor the actual levels of the administered drug and determine a dose-dependent correlation with any clinical adverse effect observed. This may permit the adoption of a patient-specific administration regime. Currently, the method of detecting EPO approved for doping control is an isoelectric-focusing, double-blotting, chemiluminescence assay based on charge differences between isoforms of rhEPOs and endogenous EPO in urine. The advantages and limitations of this method are presented. A new approach using sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a complementary tool to the established method is discussed. The application of matrix-assisted laser desorption/ionization mass spectrometry and liquid chromatography combined with tandem mass spectrometry for the direct detection of the rhEPO molecules may prove to be promising. Indirect evidence of rhEPO abuse by athletes is based on the analysis of blood parameters (hemoglobin hematocrit, reticulocytes, macrocytes, etc) and serum markers (concentration of EPO and serum transferrin receptors, etc). Enrichment of the screened parameters with gene or biochemical markers revealing altered erythropoiesis and adoption of longitudinal monitoring of athletes' hematologic and biochemical parameters could also be a complementary approach in the fight against doping.

  1. Erythropoietin in the treatment of carbon monoxide neurotoxicity in rat.

    Science.gov (United States)

    Moallem, Seyed Adel; Mohamadpour, Amir Hooshang; Abnous, Khalil; Sankian, Mojtaba; Sadeghnia, Hamid Reza; Tsatsakis, Aristidis; Shahsavand, Shabnam

    2015-12-01

    Erythropoietin (EPO) plays a critical role in the development of the nervous system. In this study, the effects of EPO in carbon monoxide (CO) neurotoxicity were examined. Rats were exposed to 3000 ppm CO for 1 h and then different doses of EPO were administrated intraperitoneally. After 24 h, glial fibrillary acidic protein (GFAP) levels in the serum were determined and water content of brain and the extravasation of a tracer (Evans blue) were measured. Brain lipid peroxidation, myeloperoxidase activity Myelin basic protein (MBP) and BAX/BcL2 protein relative expressions were determined. Cation exchange chromatography was used to evaluate MBP alterations. Seven days after exposure, pathological assessment was performed after Klüver-Barrera staining. EPO reduced malondialdehyde levels at all doses (2500, 5000 and 10,000 u/kg). Lower doses of EPO (625, 1250, 2500 u/kg) significantly decreased the elevated serum levels of GFAP. EPO could not reduce the water content of the edematous poisoned brains. However, at 5000 and 10,000 u/kg it protected the blood brain barrier against integrity loss as a result of CO. EPO could significantly decrease the MPO activity. CO-mediated oxidative stress caused chemical alterations in MBP and EPO could partially prevent these biochemical changes. Fewer vacuoles and demyelinated fibers were found in the EPO-treated animals. EPO (5000 u/kg) could restore the MBP density. CO increased brain BAX/Bcl-2 ratio 38.78%. EPO reduced it 38.86%. These results reveal that EPO could relatively prevent different pathways of neurotoxicity by CO poisoning and thus has the potential to be used as a novel approach to manage this poisoning. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Erythropoietin's Beta Common Receptor Mediates Neuroprotection in Spinal Cord Neurons.

    Science.gov (United States)

    Foley, Lisa S; Fullerton, David A; Mares, Joshua; Sungelo, Mitchell; Weyant, Michael J; Cleveland, Joseph C; Reece, T Brett

    2017-12-01

    Paraplegia from spinal cord ischemia-reperfusion (SCIR) remains an elusive and devastating complication of complex aortic operations. Erythropoietin (EPO) attenuates this injury in models of SCIR. Upregulation of the EPO beta common receptor (βcR) is associated with reduced damage in models of neural injury. The purpose of this study was to examine whether EPO-mediated neuroprotection was dependent on βcR expression. We hypothesized that spinal cord neurons subjected to oxygen-glucose deprivation would mimic SCIR injury in aortic surgery and EPO treatment attenuates this injury in a βcR-dependent fashion. Lentiviral vectors with βcR knockdown sequences were tested on neuron cell cultures. The virus with greatest βcR knockdown was selected. Spinal cord neurons from perinatal wild-type mice were harvested and cultured to maturity. They were treated with knockdown or nonsense virus and transduced cells were selected. Three groups (βcR knockdown virus, nonsense control virus, no virus control; n = 8 each) were subjected to 1 hour of oxygen-glucose deprivation. Viability was assessed. βcR expression was quantified by immunoblot. EPO preserved neuronal viability after oxygen-glucose deprivation (0.82 ± 0.04 versus 0.61 ± 0.01; p neuron preservation was similar in the nonsense virus and control mice (0.82 ± 0.04 versus 0.80 ± 0.05; p = 0.77). EPO neuron preservation was lost in βcR knockdown mice compared with nonsense control mice (0.46 ± 0.03 versus 0.80 ± 0.05; p neuronal loss after oxygen-glucose deprivation in a βcR-dependent fashion. This receptor holds immense clinical promise as a target for pharmacotherapies treating spinal cord ischemic injury. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  3. VEGF-independent angiogenic pathways induced by PDGF-C

    Science.gov (United States)

    Kumar, Anil; Zhang, Fan; Lee, Chunsik; Li, Yang; Tang, Zhongshu; Arjunan, Pachiappan

    2010-01-01

    VEGF is believed to be a master regulator in both developmental and pathological angiogenesis. The role of PDGF-C in angiogenesis, however, is only at the beginning of being revealed. We and others have shown that PDGF-C is a critical player in pathological angiogenesis because of its pleiotropic effects on multiple cellular targets. The angiogenic pathways induced by PDGF-C are, to a large extent, VEGF-independent. These pathways may include, but not limited to, the direct effect of PDGF-C on vascular cells, the effect of PDGF-C on tissue stroma fibroblasts, and its effect on macrophages. Taken together, the pleiotropic, versatile and VEGF-independent angiogenic nature of PDGF-C has placed it among the most important target genes for antiangiogenic therapy. PMID:20871734

  4. VEGF-induced Rac1 activation in endothelial cells is regulated by the guanine nucleotide exchange factor Vav2

    NARCIS (Netherlands)

    Garrett, Tiana A.; van Buul, Jaap D.; Burridge, Keith

    2007-01-01

    Vascular endothelial growth factor (VEGF) signaling is critical for both normal and disease-associated vascular development. Dysregulated VEGF signaling has been implicated in ischemic stroke, tumor angiogenesis, and many other vascular diseases. VEGF signals through several effectors, including the

  5. Molecular Pharmacology of VEGF-A Isoforms: Binding and Signalling at VEGFR2.

    Science.gov (United States)

    Peach, Chloe J; Mignone, Viviane W; Arruda, Maria Augusta; Alcobia, Diana C; Hill, Stephen J; Kilpatrick, Laura E; Woolard, Jeanette

    2018-04-23

    Vascular endothelial growth factor-A (VEGF-A) is a key mediator of angiogenesis, signalling via the class IV tyrosine kinase receptor family of VEGF Receptors (VEGFRs). Although VEGF-A ligands bind to both VEGFR1 and VEGFR2, they primarily signal via VEGFR2 leading to endothelial cell proliferation, survival, migration and vascular permeability. Distinct VEGF-A isoforms result from alternative splicing of the Vegfa gene at exon 8, resulting in VEGF xxx a or VEGF xxx b isoforms. Alternative splicing events at exons 5⁻7, in addition to recently identified posttranslational read-through events, produce VEGF-A isoforms that differ in their bioavailability and interaction with the co-receptor Neuropilin-1. This review explores the molecular pharmacology of VEGF-A isoforms at VEGFR2 in respect to ligand binding and downstream signalling. To understand how VEGF-A isoforms have distinct signalling despite similar affinities for VEGFR2, this review re-evaluates the typical classification of these isoforms relative to the prototypical, “pro-angiogenic” VEGF 165 a. We also examine the molecular mechanisms underpinning the regulation of VEGF-A isoform signalling and the importance of interactions with other membrane and extracellular matrix proteins. As approved therapeutics targeting the VEGF-A/VEGFR signalling axis largely lack long-term efficacy, understanding these isoform-specific mechanisms could aid future drug discovery efforts targeting VEGF receptor pharmacology.

  6. Expression of platelet-derived growth factor BB, erythropoietin and erythropoietin receptor in canine and feline osteosarcoma.

    Science.gov (United States)

    Meyer, F R L; Steinborn, R; Grausgruber, H; Wolfesberger, B; Walter, I

    2015-10-01

    The discovery of expression of the erythropoietin receptor (EPO-R) on neoplastic cells has led to concerns about the safety of treating anaemic cancer patients with EPO. In addition to its endocrine function, the receptor may play a role in tumour progression through an autocrine mechanism. In this study, the expression of EPO, EPO-R and platelet-derived growth factor BB (PDGF-BB) was analysed in five feline and 13 canine osteosarcomas using immunohistochemistry (IHC) and reverse transcription polymerase chain reaction (RT-PCR). EPO expression was positive in all tumours by IHC, but EPO mRNA was only detected in 38% of the canine and 40% of the feline samples. EPO-R was expressed in all samples by quantitative RT-PCR (RT-qPCR) and IHC. EPO-R mRNA was expressed at higher levels in all feline tumours, tumour cell lines, and kidney when compared to canine tissues. PDGF-BB expression was variable by IHC, but mRNA was detected in all samples. To assess the functionality of the EPO-R on tumour cells, the proliferation of canine and feline osteosarcoma cell lines was evaluated after EPO administration using an alamarBlue assay and Ki67 immunostaining. All primary cell lines responded to EPO treatment in at least one of the performed assays, but the effect on proliferation was very low indicating only a weak responsiveness of EPO-R. In conclusion, since EPO and its receptor are expressed by canine and feline osteosarcomas, an autocrine or paracrine tumour progression mechanism cannot be excluded, although in vitro data suggest a minimal role of EPO-R in osteosarcoma cell proliferation. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Study on the correlation between VEGF and peritumoral edema and tumor border in astrocytoma by CT

    International Nuclear Information System (INIS)

    Ye Yuxiang; Tan Siping; Liu Bo; Liu Guorui; Zhen Zhichao; Fan Miao

    2004-01-01

    Objective: To study the correlation between VEGF and peritumoral edema and tumor border in human astrocytoma, investigate the significance of its CT features in molecular-biology. Methods: The VEGF was examined by means of SP immunohistochemical technique in 52 cases of astrocytoma proved by pathology. The correlation of tumor VEGF with peritumoral edema, and tumor border was analyzed. Results: The peritumoral edema, tumor border and mass effect of astrocytoma was positively correlated with its VEGF. The VEGF increased with peritumoral edema and mass effect (P<0.01). VEGF were significantly higher in uncertain border group than those the clear border group (P<0.05), which VEGF were 69.2 ± 19.0. Conclusion: The over expression of VEGF obviously effect CT features in astrocytoma, such as peritumoral edema and tumor border

  8. 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

  9. Ovarian hyperstimulation syndrome is correlated with a reduction of soluble VEGF receptor protein level and a higher amount of VEGF-A.

    Science.gov (United States)

    Pietrowski, D; Szabo, L; Sator, M; Just, A; Egarter, C

    2012-01-01

    Ovarian hyperstimulation syndrome (OHSS) is a potentially life-threatening condition associated with increased vascular permeability. The vascular endothelial growth factor (VEGF) system and its receptors have been identified as the main angiogenic factors responsible for increased capillary permeability and are therefore discussed as crucial for the occurrence of OHSS. Recently, a number of soluble receptors for the VEGFs have been detected (sVEGF-Rs) and it has been shown that these sVEGF-Rs compete with the membrane-standing VEGF-R to bind VEGFs. We analyzed the serum levels of soluble VEGF-R1, -R2 and -R3 in 34 patients suffering from OHSS and in 34 controls without this disease. In a subgroup analysis, we correlated the severity of the OHSS with the detected amounts of VEGF-R1, -R2 and -R3. In addition, we determined the amount of total VEGF-A in the samples. All the three soluble VEGF receptors tended to be higher in the control group compared with that in the OHSS group but this difference only reached significance for sVEGF-R2 (mean ± SEM: 15.5 ± 0.6 versus 13.8 ± 0.5 ng/ml, respectively, P< 0.05). In the subgroup analysis, sVEGF-R2 levels decreased as the severity of OHSS increased (OHSS-I: 16.8 ± 1.9 ng/ml and OHSS-III: 12.7 ± 1.0 ng/ml, P< 0.05) Moreover, the serum levels of total VEGF-A were higher in the OHSS group than those in the controls (537.7 ± 38.9 versus 351 ± 53.4 pg/ml, respectively P< 0.05). We propose that VEGF-A plays a role in the occurrence of OHSS, that the amount of biologically available VEGF-A is modulated by sVEGF-Rs and that different combinations of VEGF-A and sVEGF-R levels might contribute to the severity of OHSS.

  10. The Effect of Erythropoietin on Testosterone Levels During Ischemia Reperfusion Injury in Rats

    Directory of Open Access Journals (Sweden)

    Tsompos C.

    2016-11-01

    Full Text Available Objective: This experimental study examined the effect of erythropoietin (Epo in a rat model and particularly in an adrenal ischemia-reperfusion (IR protocol. The effect of that molecule was studied biochemically using blood mean testosterone levels (T.

  11. 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.

  12. Expression of human erythropoietin gene in the mammary gland of a transgenic mouse

    Czech Academy of Sciences Publication Activity Database

    Mikuš, Tomáš; Malý, Petr; Poplštein, M.; Landa, Vladimír; Trefil, P.; Lidický, J.

    2001-01-01

    Roč. 47, č. 6 (2001), s. 187-195 ISSN 0015-5500 Institutional research plan: CEZ:AV0Z5052915 Keywords : erythropoietin, mammary gland, transgenic mouse Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.519, year: 2001

  13. Characterization of recombinant human erythropoietin produced in Chinese hamster ovary cells

    International Nuclear Information System (INIS)

    Davis, J.M.; Arakawa, T.; Strickland, T.W.; Yphantis, D.A.

    1987-01-01

    Physicochemical properties of recombinant human erythropoietin were examined. This protein, produced in Chinese hamster ovary cells, showed a conformation apparently identical with the natural product isolated from human urine when examined by circular dichroism, UV absorbance, and fluorescence spectroscopy. Sedimentation equilibrium experiments showed the recombinant erythropoietin preparation to be essentially a single macromolecular component with a molecular weight of 30,400 and a carbohydrate content of 39%. The Stokes radius of recombinant erythropoietin was estimated to be 32 A from gel filtration, much larger than the 20-A radius calculated for a sphere of the observed molecular weight. This difference may be ascribed to the extensive glycosylation. The fluorescence and phosphorescence spectra showed that the luminescent tryptophan(s) is (are) solvent-exposed and can be quenched by I - and acrylamide but not by Cs + . On acid titration, the recombinant erythropoietin showed a conformational transition with a midpoint of pH 4.1. This suggests that the net charges on the protein moiety rather than on the whole molecule play a role in protein structure stability

  14. [Recombinant erythropoietin as treatment for hyporegenerative anemia following hemolytic disease of the newborn].

    Science.gov (United States)

    Donato, Hugo; Bacciedoni, Viviana; García, Cecilia; Schvartzman, Gabriel; Vain, Néstor

    2009-04-01

    The aim of the study is to report results of erythropoietin treatment for late hyporegenerative anemia in the hemolytic disease of the newborn (HDN). Reports previously published concern only a few cases, with controversial results. Case series report concerning 50 neonates with HDN due to Rh, ABO or KpA antigens, aged more than 7 days. Erythropoietin treatment started when hematocrit dropped to levels requiring transfusion, with an inappropriate reticulocyte response (Reticulocyte Production Index <1). At start of treatment mean age was 24.3 +/- 12.0 days (range 8-65 days), hematocrit 24.1 +/- 2.8% (range 18-30%), and Reticulocyte Production Index 0.34 +/- 0.25 (range 0.05-0.98). Hematocrit and Reticulocyte Production Index showed significant increases after 7 and 14 days of treatment (p <0.001). No difference was observed either between infants with Rh-HDN and ABO-HDN or between Rh-HDN patients with or without intrauterine transfusions. Seven infants (14%) required one packed RBC transfusion during erythropoietin therapy, 2 of them within 72 hours from starting treatment. The percentage of transfused infants showed no difference either between ABO-HDN and Rh-HDN or between Rh-HDN with and without intrauterine transfusions. Moderate, short-lasting neutropenia, not associated to infections, was observed in 11 patients. No other adverse effect was observed. The administration of erythropoietin appears to be a safe and useful therapy. Its efficacy should be confirmed by randomized studies.

  15. Human erythropoietin response to hypocapnic hypoxia, normocapnic hypoxia, and hypocapnic normoxia

    DEFF Research Database (Denmark)

    Klausen, T; Christensen, H; Hansen, J M

    1996-01-01

    This study investigated the human erythropoietin (EPO) response to short-term hypocapnic hypoxia, its relationship to a normoxic or hypoxic increase of the haemoglobin oxygen affinity, and its suppression by the addition of CO2 to the hypoxic gas. On separate days, eight healthy male subjects were...

  16. 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

    -life and plasma clearance of intravenously injected recombinant human erythropoietin (rhEPO) were determined. The results indicate that the lack of compensatory increase in serum EPO to the anaemic stimulus is not due to increased catabolism, but to decreased synthesis of the renal hormone. Two patients were...

  17. Lentivirus administration to rat muscle provides efficient sustained expression of erythropoietin

    NARCIS (Netherlands)

    Seppen, J.; Barry, S. C.; Harder, B.; Osborne, W. R.

    2001-01-01

    A lentivirus pseudotyped with vesicular stomatitis virus G protein (VSV-G) encoding rat erythropoietin (EPO) complementary DNA was administered to rat skeletal muscle and red blood cell production was serially monitored. After a single intramuscular injection hematocrit values increased and reached

  18. Therapeutic levels of erythropoietin (EPO) achieved after gene electrotransfer to skin in mice

    DEFF Research Database (Denmark)

    Gothelf, A; Hojman, P; Gehl, Julie

    2010-01-01

    Gene electrotransfer refers to gene transfection by electroporation and is an effective non-viral method for delivering naked DNA into cells and tissues. This study presents data from gene electrotransfer with erythropoietin (EPO) to mouse skin. Nine-week-old female NMRI mice received one, two...

  19. 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...

  20. Erythropoietin in the cerebrospinal fluid of patients with aneurysmal subarachnoid haemorrhage originates from the brain

    DEFF Research Database (Denmark)

    Springborg, Jacob Bertram; Sonne, Bjarne; Frederiksen, Hans Jørgen

    2003-01-01

    Recent years' research has revealed a specific, neuroprotective erythropoietin (EPO) system in the central nervous system (CNS) that is upregulated by hypoxia. The presence and dynamics of EPO in the cerebrospinal fluid (CSF) of patients with subarachnoid haemorrhage (SAH) has not been investigated...

  1. Tyrosine kinase receptor RON functions downstream of the erythropoietin receptor to induce expansion of erythroid progenitors

    NARCIS (Netherlands)

    van den Akker, Emile; van Dijk, Thamar; Parren-van Amelsvoort, Martine; Grossmann, Katja S.; Schaeper, Ute; Toney-Earley, Kenya; Waltz, Susan E.; Löwenberg, Bob; von Lindern, Marieke

    2004-01-01

    Erythropoietin (EPO) is required for cell survival during differentiation and for progenitor expansion during stress erythropoiesis. Although signaling pathways may couple directly to docking sites on the EPO receptor (EpoR), additional docking molecules expand the signaling platform of the

  2. Control of erythropoiesis by erythropoietin and stem cell factor: a novel role for Bruton's tyrosine kinase

    NARCIS (Netherlands)

    von Lindern, Marieke; Schmidt, Uwe; Beug, Hartmut

    2004-01-01

    Erythropoietin (Epo) and stem cell factor (SCF) are essential factors in the control of survival, expansion and differentiation of erythroid progenitors. Upon activation, their receptors, the EpoR and c-Kit, initiate multiple signalling pathways that control many cellular processes. To control

  3. Erythropoietin Receptor in Human Tumor Cells: Expression and Aspects Regarding Functionality

    NARCIS (Netherlands)

    T.A. Knoch (Tobias); G. Westphal; E. Niederberger; C. Blum; Y. Wollman; W. Rebel; J. Debus; E. Friedrich

    2001-01-01

    textabstractRecombinant human erythropoietin (Epo)and granu l o cy t e - c o l o ny - s t i mulating factor (G-CSF) are used to stimulate hematopoiesis in patients with malignant dise a s e s . These cytokines transduce their biological signal via the Epo receptor (EpoR) and G-CSF receptor (G-CSF-R)

  4. Active Smoking and Hematocrit and Fasting Circulating Erythropoietin Concentrations in the General Population

    NARCIS (Netherlands)

    Eisenga, Michele F.; Kieneker, Lyanne M.; Touw, Daan J.; Nolte, Ilja M.; van der Meer, Peter; Huls, Gerwin; Gaillard, Carlo A. J. M.; Bakker, Stephan J. L.

    Cigarette smoking continues to be one of the major risk factors for increased morbidity and mortality worldwide. Among many adverse health effects, smoking can induce erythrocytosis, which is commonly believed to result from elevated serum erythropoietin (EPO) levels. Currently, however, this notion

  5. Comparison of Hemoglobin Levels Before and After Hemodialysis and Their Effects on Erythropoietin Dosing and Cost

    OpenAIRE

    Sagheb; Fallahzadeh; Moaref; Fallahzadeh; Dormanesh

    2016-01-01

    Background Hemoglobin levels measured after hemodialysis, as compared to hemoglobin levels measured before hemodialysis, are suggested to be a more accurate reflection of the hemoglobin levels between hemodialysis sessions, and to be a better reference point for adjusting erythropoietin dosing. Objectives The aim of this study was to compare the hemoglobin levels before and after hemodialysis, to calculate the required erythropoie...

  6. Increased serum erythropoietin activity in rats following intrarenal injection of nickel subsulfide

    International Nuclear Information System (INIS)

    Hopfer, S.M.; Sunderman, F.W. Jr.; Fredrickson, T.N.; Morse, E.E.

    1979-01-01

    To investigate the pathopysiologic mechanisms of nickel-induced erythocytosis, serum erythropoietin activities were measured in (a) pooled serum from rats at 2 wk after intrarenal injection of αNi 3 S 2 (5 mg/rat), and (b) pooled serum from control rats at 2 wk after intrarenal injection of sterile NaCl vehicle (0.4 ml/rat). A sensitive erythropoietin bioassay was employed, which entailed repetitive administration of test serums to post-hypoxic polycythemic mice in divided doses (12 s.c. injections of 0.5 ml of serum at 6 h intervals for 3 da; total dose = 6 ml of serum/mouse). The erythropoietin detection limit was approx. = 20 I.U./liter of serum. In mice which received pooled serum from αNi 3 S 2 -treated rats, erythrocyte 59 Fe-uptake averaged 28% (S.D. +- 5) (vs 3.7 +- 1.1% in control rats; P 3 S 2 -treated rats averaged 130 I.U./liter (S.D. +- 18) (vs 27 +- 6 I.U./liter in control rats; P 3 S 2 is mediated by increased serum erythropoietin activity

  7. Soluble vascular endothelial growth factor (VEGF) receptor-1 inhibits migration of human monocytic THP-1 cells in response to VEGF.

    Science.gov (United States)

    Zhu, Cansheng; Xiong, Zhaojun; Chen, Xiaohong; Lu, Zhengqi; Zhou, Guoyu; Wang, Dunjing; Bao, Jian; Hu, Xueqiang

    2011-08-01

    We aimed to investigate the regulation and contribution of vascular endothelial growth factor (VEGF) and sFlt-1(1-3) to human monocytic THP-1 migration. Ad-sFlt-1/FLAG, a recombinant adenovirus carrying the human sFlt-1(1-3) (the first three extracellular domains of FLT-1, the hVEGF receptor-1) gene, was constructed. L929 cells were infected with Ad-sFlt-1/FLAG and the expression of sFlt-1 was detected by immunofluorescent assay and ELISA. Corning(®) Transwell(®) Filter Inserts containing polyethylene terephthalate (PET) membranes with pore sizes of 3 μm were used as an experimental model to simulate THP-1 migration. Five VEGF concentrations (0, 0.1, 1, 10 and 100 ng/ml), four concentrations of sFlt-1(1-3)/FLAG expression supernatants (0.1, 1, 10 and 100 ng/ml), and monocyte chemoattractant protein-1 (MCP-1, 10 ng/ml) were used to test the ability of THP-1 cells to migrate through PET membranes. The sFlt-1(1-3) gene was successfully recombined into Ad-sFlt-1/FLAG. sFlt-1(1-3) was expressed in L929 cells transfected with Ad-sFlt-1/FLAG. THP-1 cell migration increased with increasing concentrations of VEGF, while cell migration decreased with increasing concentrations of sFlt1(1-3)/FLAG. sFlt1(1-3)/FLAG had no effect on MCP-1-induced cell migration. This study demonstrated that VEGF is able to elicit a migratory response in THP-1 cells, and that sFlt-1(1-3) is an effective inhibitor of THP-1 migration towards VEGF.

  8. 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

  9. VEGF-C gene therapy augments postnatal lymphangiogenesis and ameliorates secondary lymphedema

    OpenAIRE

    Yoon, Young-sup; Murayama, Toshinori; Gravereaux, Edwin; Tkebuchava, Tengiz; Silver, Marcy; Curry, Cynthia; Wecker, Andrea; Kirchmair, Rudolf; Hu, Chun Song; Kearney, Marianne; Ashare, Alan; Jackson, David G.; Kubo, Hajime; Isner, Jeffrey M.; Losordo, Douglas W.

    2003-01-01

    Although lymphedema is a common clinical condition, treatment for this disabling condition remains limited and largely ineffective. Recently, it has been reported that overexpression of VEGF-C correlates with increased lymphatic vessel growth (lymphangiogenesis). However, the effect of VEGF-C–induced lymphangiogenesis on lymphedema has yet to be demonstrated. Here we investigated the impact of local transfer of naked plasmid DNA encoding human VEGF-C (phVEGF-C) on two animal models of lymphed...

  10. 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

  11. Caveat Oncologist: Clinical Findings and Consequences of Distributing Counterfeit Erythropoietin in the United States

    Science.gov (United States)

    Qureshi, Zaina P.; Norris, LeAnn; Sartor, Oliver; McKoy, June M.; Armstrong, John; Raisch, Dennis W.; Garg, Vishvas; Stafkey-Mailey, Dana; Bennett, Charles Lee

    2012-01-01

    Purpose: Counterfeit pharmaceuticals pose risks domestically. Because of their cost, cancer pharmaceuticals are vulnerable. We review findings from a domestic counterfeiting episode involving erythropoietin and outline anticounterfeiting recommendations for policy makers, patients, and health care professionals. Materials and Methods: Information was obtained on patients who received counterfeit erythropoietin, its distribution, and criminal investigations into counterfeiting networks. Interview sources included a physician, an attorney, employees of the Florida Department of Health and Human Services and the US Food and Drug Administration's (FDA) Office of Criminal Investigation, manufacturers, and wholesalers. Other sources included the book “Dangerous Doses,” LexisNexis (search terms “counterfeit” and “erythropoietin”) and the FDA database. Results: Counterfeit product consisted of 2,000 U vials with counterfeit labels denoting 40,000 U. The counterfeiters, in collaboration with a Miami pharmacy, purchased 110,000 erythropoietin 2,000 U vials and affixed counterfeit labels to each vial. Products were then sold via the pharmaceutical “gray market” to wholesalers, then pharmacy chains. Investigations by Florida government officials implicated 17 persons, all of whom were found guilty of trafficking in counterfeit pharmaceuticals. Despite the large size of the operation, the FDA received reports of only 12 patients who had received counterfeit erythropoietin and detailed information for only two individuals. A 17-year-old liver transplant recipient and a 61-year-old patient with breast cancer experienced loss of efficacy after receiving counterfeit erythropoietin. Conclusion: Wider use of FDA anticounterfeit initiatives, limiting pharmaceutical suppliers to reputable distributors, and educating providers and patients about signs of counterfeit drugs can improve the safety of cancer pharmaceuticals. PMID:23077434

  12. 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 ....... For both molecules, large biological variation and lack of standardization of assay procedures are major challenges....

  13. 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

  14. Polymorphism of the VEGF gene and its association with growth ...

    African Journals Online (AJOL)

    Thus, mutations of this gene may exert a significant influence on animal growth. We screened the exons of the caprine VEGF gene using PCR-SSCP and DNA sequencing methods in 459 individuals from four goat breeds to identify sequence variations that may have an effect on protein structure and function, and might be ...

  15. Polymorphism of the VEGF gene and its association with growth ...

    African Journals Online (AJOL)

    User

    Keywords: VEGF gene, caprine, single nucleotide polymorphism (SNP), genetic variation, PCR-SSCP ... This field is strongly focusing on gene loci and polymorphisms that have ..... Enhance the efficiency of single-strand conformation polymorphism analysis by short polyacrylamide gel and modified silver staining. Anal.

  16. [Systemic safety following intravitreal injections of anti-VEGF].

    Science.gov (United States)

    Baillif, S; Levy, B; Girmens, J-F; Dumas, S; Tadayoni, R

    2018-03-01

    The goal of this manuscript is to assess data suggesting that intravitreal injection of anti-vascular endothelial growth factors (anti-VEGFs) could result in systemic adverse events (AEs). The class-specific systemic AEs should be similar to those encountered in cancer trials. The most frequent AE observed in oncology, hypertension and proteinuria, should thus be the most common expected in ophthalmology, but their severity should be lower because of the much lower doses of anti-VEGFs administered intravitreally. Such AEs have not been frequently reported in ophthalmology trials. In addition, pharmacokinetic and pharmacodynamic data describing systemic diffusion of anti-VEGFs should be interpreted with caution because of significant inconsistencies reported. Thus, safety data reported in ophthalmology trials and pharmacokinetic/pharmacodynamic data provide robust evidence that systemic events after intravitreal injection are very unlikely. Additional studies are needed to explore this issue further, as much remains to be understood about local and systemic side effects of anti-VEGFs. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  17. Mural cell associated VEGF is required for organotypic vessel formation.

    Directory of Open Access Journals (Sweden)

    Lasse Evensen

    Full Text Available BACKGROUND: Blood vessels comprise endothelial cells, mural cells (pericytes/vascular smooth muscle cells and basement membrane. During angiogenesis, mural cells are recruited to sprouting endothelial cells and define a stabilizing context, comprising cell-cell contacts, secreted growth factors and extracellular matrix components, that drives vessel maturation and resistance to anti-angiogenic therapeutics. METHODS AND FINDINGS: To better understand the basis for mural cell regulation of angiogenesis, we conducted high content imaging analysis on a microtiter plate format in vitro organotypic blood vessel system comprising primary human endothelial cells co-cultured with primary human mural cells. We show that endothelial cells co-cultured with mural cells undergo an extensive series of phenotypic changes reflective of several facets of blood vessel formation and maturation: Loss of cell proliferation, pathfinding-like cell migration, branching morphogenesis, basement membrane extracellular matrix protein deposition, lumen formation, anastamosis and development of a stabilized capillary-like network. This phenotypic sequence required endothelial-mural cell-cell contact, mural cell-derived VEGF and endothelial VEGFR2 signaling. Inhibiting formation of adherens junctions or basement membrane structures abrogated network formation. Notably, inhibition of mural cell VEGF expression could not be rescued by exogenous VEGF. CONCLUSIONS: These results suggest a unique role for mural cell-associated VEGF in driving vessel formation and maturation.

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

    African Journals Online (AJOL)

    Methods: Twenty-one ulcerative colitis (UC), 14 Crohn's disease (CD), 11 colorectal cancer patients, and 11 healthy controls colonic biopsy samples were evaluated immunohistochemically. Results: The expressions of TSP-1, VEGF, and iNOS in UC and CD groups were higher than expression in healthy control group, ...

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

    African Journals Online (AJOL)

    Enas Mohamed Ali

    a Cancer Management and Research Department, Alexandria University, Egypt ... and followed for 4 years and 30 females with benign breast lesions matched with ... Results: The mean serum level of VEGF elevated in breast cancer patients .... 120 patients of non metastatic breast cancer. Number. Percent. Age. <50. 78.

  20. [VEGF expression in dog retina after chorioretinal venous anastomosis].

    Science.gov (United States)

    Lu, Ning; Li, Zhihui; Sun, Xianli; Wang, Guanglu; Zhang, Feng; Peng, Xiaoyan

    2002-09-01

    To identify changes in vascular endothelial growth factor (VEGF) expression in the dog retina after laser-induced chorioretinal venous anastomosis (CRVA), in order to find out the relationship between CRVA treatment and the related neovascular complications. Immediately after branch retinal vein occlusion (BRVO) model was made in 5 eyes of 5 normal dogs, CRVA treatment was done over a small tributary vein in the drainage distribution of the occluded vein. In each eye, there were 2 - 3 treatment sites. Four to six weeks later, a repeated treatment was given if the first treatment failed to show the anastomosis. The treatment sites with successful CRVA were divided into two groups: the small laser spot group, which received one treatment and the big laser spot group, which received more than one treatment. The expression of VEGF was investigated immunohistochemically in the treatment sites with successful anastomoses and in the 5 normal fellow eyes (control). There were totally 10 successful anastomoses in the 5 experimental eyes, among which, five received one treatment and the other 5 received more than one treatment. On fundus examination, the small laser spots were round and small, and the big laser spots were large with local proliferation. VEGF immunoreactivity was absent/weak in the normal dog retina, and remained unchanged in the small laser spot group, but somewhat increased in the big laser spot group. No neovascular complications occurred. All immunostaining experiments were accompanied by proper controls and none of the negative controls showed any immunoreactivity. Proper laser treatment can induce CRVA quite safely in nonischemic dog retina, which does not cause changes in the expression of VEGF, but severe laser damage in the treatment site can cause increased VEGF expression which may be related to neovascular complications.

  1. Radioiodinated VEGF to image tumor angiogenesis in a LS180 tumor xenograft model

    International Nuclear Information System (INIS)

    Yoshimoto, Mitsuyoshi; Kinuya, Seigo; Kawashima, Atsuhiro; Nishii, Ryuichi; Yokoyama, Kunihiko; Kawai, Keiichi

    2006-01-01

    Introduction: Angiogenesis is essential for tumor growth or metastasis. A method involving noninvasive detection of angiogenic activity in vivo would provide diagnostic information regarding antiangiogenic therapy targeting vascular endothelial cells as well as important insight into the role of vascular endothelial growth factor (VEGF) and its receptor (flt-1 and KDR) system in tumor biology. We evaluated radioiodinated VEGF 121 , which displays high binding affinity for KDR, and VEGF 165 , which possesses high binding affinity for flt-1 and low affinity for KDR, as angiogenesis imaging agents using the LS180 tumor xenograft model. Methods: VEGF 121 and VEGF 165 were labeled with 125 I by the chloramine-T method. Biodistribution was observed in an LS180 human colon cancer xenograft model. Additionally, autoradiographic imaging and immunohistochemical staining of tumors were performed with 125 I-VEGF 121 . Results: 125 I-VEGF 121 and 125 I-VEGF 165 exhibited strong, continuous uptake by tumors and the uterus, an organ characterized by angiogenesis. 125 I-VEGF 121 uptake in tumors was twofold higher than that of 125 I-VEGF 165 (9.12±98 and 4.79±1.08 %ID/g at 2 h, respectively). 125 I-VEGF 121 displayed higher tumor to nontumor (T/N) ratios in most normal organs in comparison with 125 I-VEGF 165 . 125 I-VEGF 121 accumulation in tumors decreased with increasing tumor volume. Autoradiographic and immunohistochemical analyses confirmed that the difference in 125 I-VEGF 121 tumor accumulation correlated with degree of tumor vascularity. Conclusion: Radioiodinated VEGF 121 is a promising tracer for noninvasive delineation of angiogenesis in vivo

  2. VEGF induces sensory and motor peripheral plasticity, alters bladder function, and promotes visceral sensitivity.

    Science.gov (United States)

    Malykhina, Anna P; Lei, Qi; Erickson, Chris S; Epstein, Miles L; Saban, Marcia R; Davis, Carole A; Saban, Ricardo

    2012-12-19

    This work tests the hypothesis that bladder instillation with vascular endothelial growth factor (VEGF) modulates sensory and motor nerve plasticity, and, consequently, bladder function and visceral sensitivity.In addition to C57BL/6J, ChAT-cre mice were used for visualization of bladder cholinergic nerves. The direct effect of VEGF on the density of sensory nerves expressing the transient receptor potential vanilloid subfamily 1 (TRPV1) and cholinergic nerves (ChAT) was studied one week after one or two intravesical instillations of the growth factor.To study the effects of VEGF on bladder function, mice were intravesically instilled with VEGF and urodynamic evaluation was assessed. VEGF-induced alteration in bladder dorsal root ganglion (DRG) neurons was performed on retrogradly labeled urinary bladder afferents by patch-clamp recording of voltage gated Na+ currents. Determination of VEGF-induced changes in sensitivity to abdominal mechanostimulation was performed by application of von Frey filaments. In addition to an overwhelming increase in TRPV1 immunoreactivity, VEGF instillation resulted in an increase in ChAT-directed expression of a fluorescent protein in several layers of the urinary bladder. Intravesical VEGF caused a profound change in the function of the urinary bladder: acute VEGF (1 week post VEGF treatment) reduced micturition pressure and longer treatment (2 weeks post-VEGF instillation) caused a substantial reduction in inter-micturition interval. In addition, intravesical VEGF resulted in an up-regulation of voltage gated Na(+) channels (VGSC) in bladder DRG neurons and enhanced abdominal sensitivity to mechanical stimulation. For the first time, evidence is presented indicating that VEGF instillation into the mouse bladder promotes a significant increase in peripheral nerve density together with alterations in bladder function and visceral sensitivity. The VEGF pathway is being proposed as a key modulator of neural plasticity in the pelvis and

  3. VEGF induces sensory and motor peripheral plasticity, alters bladder function, and promotes visceral sensitivity

    Directory of Open Access Journals (Sweden)

    Malykhina Anna P

    2012-12-01

    Full Text Available Abstract Background This work tests the hypothesis that bladder instillation with vascular endothelial growth factor (VEGF modulates sensory and motor nerve plasticity, and, consequently, bladder function and visceral sensitivity. In addition to C57BL/6J, ChAT-cre mice were used for visualization of bladder cholinergic nerves. The direct effect of VEGF on the density of sensory nerves expressing the transient receptor potential vanilloid subfamily 1 (TRPV1 and cholinergic nerves (ChAT was studied one week after one or two intravesical instillations of the growth factor. To study the effects of VEGF on bladder function, mice were intravesically instilled with VEGF and urodynamic evaluation was assessed. VEGF-induced alteration in bladder dorsal root ganglion (DRG neurons was performed on retrogradly labeled urinary bladder afferents by patch-clamp recording of voltage gated Na+ currents. Determination of VEGF-induced changes in sensitivity to abdominal mechanostimulation was performed by application of von Frey filaments. Results In addition to an overwhelming increase in TRPV1 immunoreactivity, VEGF instillation resulted in an increase in ChAT-directed expression of a fluorescent protein in several layers of the urinary bladder. Intravesical VEGF caused a profound change in the function of the urinary bladder: acute VEGF (1 week post VEGF treatment reduced micturition pressure and longer treatment (2 weeks post-VEGF instillation caused a substantial reduction in inter-micturition interval. In addition, intravesical VEGF resulted in an up-regulation of voltage gated Na+ channels (VGSC in bladder DRG neurons and enhanced abdominal sensitivity to mechanical stimulation. Conclusions For the first time, evidence is presented indicating that VEGF instillation into the mouse bladder promotes a significant increase in peripheral nerve density together with alterations in bladder function and visceral sensitivity. The VEGF pathway is being proposed as a

  4. Differential effects of erythropoietin on neural and cognitive measures of executive function 3 and 7 days post-administration

    DEFF Research Database (Denmark)

    Miskowiak, Kamilla; Inkster, Becky; O'Sullivan, Ursula

    2008-01-01

    Erythropoietin (Epo) has neuroprotective and neurotrophic effects and improves cognitive function in animal models of neurodegenerative and neuropsychiatric illness. In humans, weekly Epo administration over 3 months improves cognitive function in schizophrenia. The neural underpinnings and time...

  5. Comparison of erythropoietic response to erythropoietin-secreting stimuli in mice following polycythemia induced by transfusion or hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Alippi, R.M.; Barcelo, A.C.; Bozzini, C.E.

    1985-03-01

    The erythropoietic response, measured as RBC-/sup 59/Fe uptake, in response to either 24-h exposure to hypoxia or administration of dexamethasone, isoproterenol, testosterone, or erythropoietin, was determined in both posthypoxic (PH) and hypertransfused (HT) polycythemic mice. Highly significant differences between PH and HT mice exposed to hypoxia or injected with dexamethasone, isoproterenol, or testosterone were observed, isotope incorporation being always higher in PH than in HT mice. On the other hand, the response to erythropoietin did not show a significant difference between PH and HT mice. These results suggest that PH mice have been preconditioned by exposure to hypoxia in a way that makes them more sensitive to at least some kinds of erythropoietic stimuli. Since these stimuli have been shown by others to increase erythropoietin production, the results support the hypothesis that hypoxia induces sensitization of the erythropoietin- producing organ(s).

  6. Potent neutralization of VEGF biological activities with a fully human antibody Fab fragment directed against VEGF receptor 2

    International Nuclear Information System (INIS)

    Miao, H.-Q.; Hu, Kun; Jimenez, Xenia; Navarro, Elizabeth; Zhang, Haifan; Lu Dan; Ludwig, Dale L.; Balderes, Paul; Zhu Zhenping

    2006-01-01

    Compelling evidence suggest that vascular endothelial growth factor (VEGF) and its receptors, especially receptor 2 (VEGFR2, or kinase insert domain-containing receptor, KDR), play a critical role in angiogenesis under both physiological and pathological conditions, including cancer and angiogenic retinopathies such as age-related macular degeneration (AMD). To this end, inhibition of angiogenesis with antagonists to either VEGF or KDR has yielded significant therapeutic efficacy both in preclinical studies in animal models and in clinical trials in patients with cancer and AMD. We previously reported the identification of a high affinity, fully human anti-KDR antibody fragment, 1121B Fab, through a highly stringent affinity maturation process with a Fab originally isolated from a naive human antibody phage display library. In this study, we demonstrate that 1121B Fab is able to strongly block KDR/VEGF interaction, resulting in potent inhibition of an array of biological activities of VEGF, including activation of the receptor and its signaling pathway, intracellular calcium mobilization, and migration and proliferation of endothelial cells. Taken together, our data lend strong support to the further development of 1121B Fab fragment as an anti-angiogenesis agent in both cancer and angiogenic retinopathies

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

    DEFF Research Database (Denmark)

    Høier, Birgitte; Hellsten, Ylva

    2014-01-01

    , such as shear stress and passive stretch, lead to cellular signalling, enhanced expression of angiogenic factors and initiation of capillary growth. The most central angiogenic factor in skeletal muscle capillary growth is vascular endothelial growth factor (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...

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

    OpenAIRE

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

    2015-01-01

    Background and Purpose 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-?-d-glucoside, also known ...

  9. 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.

  10. 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.

  11. 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.

  12. 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.

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

    Science.gov (United States)

    Fearnley, Gareth W; Smith, Gina A; Abdul-Zani, Izma; Yuldasheva, Nadira; Mughal, Nadeem A; Homer-Vanniasinkam, Shervanthi; Kearney, Mark T; Zachary, Ian C; Tomlinson, Darren C; Harrison, Michael A; Wheatcroft, Stephen B; Ponnambalam, Sreenivasan

    2016-05-15

    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. © 2016. Published by The Company of Biologists Ltd.

  14. Clinical significance of determination of serum VEGF and CEA levels in patients with colorectal cancer

    International Nuclear Information System (INIS)

    Du Xiaohui; Song Shaobai; Zheng Wei

    2007-01-01

    Objective: To study the applicability of combined determination of serum VEGF and CEA levels in the diagnosis of colorectal cancer as well as the relationship between VEGF level and stage of the disease. Methods: Serum VEGF (with ELISA) and CEA (with RIA) levels serum were detected in 28 patients with colorectal cancer of various stages and 29 controls. Results: The diagnostic positive rate was 53.6% (15/28), 39.3% (11/28), 71.4% (20/28) with CEA, VEGF and combined test for colorectal cancer, respectively. The serum VEGF levels in patients with advance colorectal cancer were significantly higher than those in patients with earlier stages diseases and controls, VEGF levels were positively correlated with CEA levels (P<0.05). Conclusion: Combined detection of the levels of serum VEGF and CEA could improve significantly the diagnostic positive rate in patients with colorectal cancer. (authors)

  15. VEGF-production by CCR2-dependent macrophages contributes to laser-induced choroidal neovascularization.

    Directory of Open Access Journals (Sweden)

    Torsten A Krause

    Full Text Available Age-related macular degeneration (AMD is the most prevalent cause of blindness in the elderly, and its exsudative subtype critically depends on local production of vascular endothelial growth factor A (VEGF. Mononuclear phagocytes, such as macrophages and microglia cells, can produce VEGF. Their precursors, for example monocytes, can be recruited to sites of inflammation by the chemokine receptor CCR2, and this has been proposed to be important in AMD. To investigate the role of macrophages and CCR2 in AMD, we studied intracellular VEGF content in a laser-induced murine model of choroidal neovascularisation. To this end, we established a technique to quantify the VEGF content in cell subsets from the laser-treated retina and choroid separately. 3 days after laser, macrophage numbers and their VEGF content were substantially elevated in the choroid. Macrophage accumulation was CCR2-dependent, indicating recruitment from the circulation. In the retina, microglia cells were the main VEGF+ phagocyte type. A greater proportion of microglia cells contained VEGF after laser, and this was CCR2-independent. On day 6, VEGF-expressing macrophage numbers had already declined, whereas numbers of VEGF+ microglia cells remained increased. Other sources of VEGF detectable by flow cytometry included in dendritic cells and endothelial cells in both retina and choroid, and Müller cells/astrocytes in the retina. However, their VEGF content was not increased after laser. When we analyzed flatmounts of laser-treated eyes, CCR2-deficient mice showed reduced neovascular areas after 2 weeks, but this difference was not evident 3 weeks after laser. In summary, CCR2-dependent influx of macrophages causes a transient VEGF increase in the choroid. However, macrophages augmented choroidal neovascularization only initially, presumably because VEGF production by CCR2-independent eye cells prevailed at later time points. These findings identify macrophages as a relevant source

  16. 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.

  17. 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...

  18. Effects of prolonged recombinant human erythropoietin administration on muscle membrane transport systems and metabolic marker enzymes

    DEFF Research Database (Denmark)

    Juel, C; Thomsen, J J; Rentsch, R L

    2007-01-01

    on the expression of muscle membrane transport proteins. Likewise, improvements in performance may involve upregulation of metabolic enzymes. Since Epo is known to augment performance we tested the effect of rHuEpo on some marker enzymes that are related to aerobic capacity. For these purposes eight subjects...... performance by approximately 54%. Membrane transport systems and carbonic anhydrases involved in pH regulation remained unchanged. Of the Na(+), K(+)-pump isoforms only the density of the alpha2 subunit was decreased (by 22%) after treatment. The marker enzymes cytochrom c and hexokinase remained unchanged......Adaptations to chronic hypoxia involve changes in membrane transport proteins. The underlying mechanism of this response may be related to concomitant occurring changes in erythropoietin (Epo) levels. We therefore tested the direct effects of recombinant human erythropoietin (rHuEpo) treatment...

  19. 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.

  20. Metronomic chemotherapy in metastatic breast cancer Impact on VEGF

    International Nuclear Information System (INIS)

    Ezz El-Arab, L.R.; Menha Swellam, M.; El Mahdy, M.M.

    2012-01-01

    Background: Anticancer chemotherapy is thought to be effective by means of direct cytotoxicity on tumor cells. Alternative mechanisms of efficacy have been ascribed to several common anticancer agents; including cyclophosphamide (CTX) and capecitabine (Cap) when given at lower doses for prolonged period (metronomic chemotherapy) postulating an antiangiogenic activity as well, Aim of work :To evaluate the action and tolerability of metronomic chemotherapy (MC) and its impact on serum vascular endothetial growth factor (VEGF) levels in metastatic breast cancer (MBC) patients. Patients and methods: In this study we evaluated the clinical efficacy and tolerability of low dose, capecitabine (500 mg twice daily) together with oral cyclophosphamide (CTX) (a dose of 50 mg once daily) in patients with metastatic breast cancer. Vascular endothelial growth factor (VEGF), an angiogenic marker, was measured in the serum samples; at base line, and after 2 and 6 months of therapy. Results: Sixty patients were evaluable. One achieved complete response (CR), 12 partial responses (PR), and 21 stable diseases (SD), while 26 were with progressive disease (PD). The overall response rate was 21.7% with overall disease control (CR, PR, and SD) 56.7%. The median time to progression was 7±2.59 months and overall survival 16 ±8.02 months. Toxicity was mild, Palmar-plantar erythrodythesia was the must common side effect and was observed in 22 patients (37%), leucopenia (Gl + 2) was the most common hematological toxicity, and it was reported in 27% of the cases. The median VEGF level was significantly declined after 2 and 6 months of therapy compared to the base line among the patients with disease control (CR, PR, and SD). In multivariate logisatic regression analysis, patients with post-menopausal, positive hormonal receptors, negative HER-2/Neu, and one, metastatic site, were statistically significant and have a better disease control rate. Coclcusions: MC induced drop in VEGF, and was

  1. VEGF blockade inhibits angiogenesis and reepithelialization of endometrium

    OpenAIRE

    Fan, Xiujun; Krieg, Sacha; Kuo, Calvin J.; Wiegand, Stanley J.; Rabinovitch, Marlene; Druzin, Maurice L.; Brenner, Robert M.; Giudice, Linda C.; Nayak, Nihar R.

    2008-01-01

    Despite extensive literature on vascular endothelial growth factor (VEGF) expression and regulation by steroid hormones, the lack of clear understanding of the mechanisms of angiogenesis in the endometrium is a major limitation for use of antiangiogenic therapy targeting endometrial vessels. In the current work, we used the rhesus macaque as a primate model and the decidualized mouse uterus as a murine model to examine angiogenesis during endometrial breakdown and regeneration. We found that ...

  2. VEGF Correlates with Inflammation and Fibrosis in Tuberculous Pleural Effusion

    OpenAIRE

    Bien, Mauo-Ying; Wu, Ming-Ping; Chen, Wei-Lin; Chung, Chi-Li

    2015-01-01

    Objective. To investigate the relationship among angiogenic cytokines, inflammatory markers, and fibrinolytic activity in tuberculous pleural effusion (TBPE) and their clinical importance. Methods. Forty-two patients diagnosed with TBPE were studied. Based on chest ultrasonography, there were 26 loculated and 16 nonloculated TBPE patients. The effusion size radiological scores and effusion vascular endothelial growth factor (VEGF), interleukin- (IL-) 8, plasminogen activator inhibitor type-1 ...

  3. Form CMS-2728 data versus erythropoietin claims data: implications for quality of care studies.

    Science.gov (United States)

    Beaubrun, Anne C; Kanda, Eiichiro; Bond, T Christopher; McClellan, William M

    2013-01-01

    Medical Evidence Report Form CMS-2728 data is frequently used to study US dialysis patients, but the validity of these data have been called into question. We compared predialysis erythropoietin use as recorded on Form CMS-2728 with claims data as part of an assessment of quality of care among hemodialysis patients. Medicare claims were linked to Form CMS-2728 data for 18,870 patients. Dialysis patients, 67 years old or older, who started dialysis from 1 June 2005 to 31 May 2007 were eligible. Logistic and multivariate regressions were used to compare the use of either Form CMS-2728 or the corresponding claims data to predict mortality and the probability of meeting target hemoglobin levels. The sensitivity, specificity, and kappa coefficient for the predialysis erythropoietin indicator were 58.0%, 78.4%, and 0.36, respectively. Patients with a predialysis erythropoietin claim were less likely to die compared with patients without a claim (odds ratio = 0.80 and 95% confidence interval = 0.74-0.87), but there was no relationship observed between predialysis care and death using only Form CMS-2728 predictors. At the facility level, a predialysis erythropoietin claim was associated with a 0.085 increase in the rate of meeting target hemoglobin levels compared with patients without a claim (p = 0.041), but no statistically significant relationship was observed when using the Form CMS-2728 indicators. The agreement between Form CMS-2728 and claims data is poor and discordant results are observed when comparing the use of these data sources to predict health outcomes. Facilities with higher agreement between the two data sources may provide greater quality of care.

  4. Increased Levels of Erythropoietin in Nipple Aspirate Fluid and in Ductal Cells from Breast Cancer Patients

    Directory of Open Access Journals (Sweden)

    Ferdinando Mannello

    2008-01-01

    Full Text Available Background: Erythropoietin (Epo is an important regulator of erythropoiesis, and controls proliferation and differentiation of both erythroid and non-erythroid tissues. Epo is actively synthesized by breast cells during lactation, and also plays a role in breast tissues promoting hypoxia-induced cancer initiation. Our aims are to perform an exploratory investigation on the Epo accumulation in breast secretions from healthy and cancer patients and its localization in breast cancer cells.

  5. VEGF-B is dispensable for blood vessel growth but critical for their survival, and VEGF-B targeting inhibits pathological angiogenesis

    Science.gov (United States)

    Zhang, Fan; Tang, Zhongshu; Hou, Xu; Lennartsson, Johan; Li, Yang; Koch, Alexander W.; Scotney, Pierre; Lee, Chunsik; Arjunan, Pachiappan; Dong, Lijin; Kumar, Anil; Rissanen, Tuomas T.; Wang, Bin; Nagai, Nobuo; Fons, Pierre; Fariss, Robert; Zhang, Yongqing; Wawrousek, Eric; Tansey, Ginger; Raber, James; Fong, Guo-Hua; Ding, Hao; Greenberg, David A.; Becker, Kevin G.; Herbert, Jean-Marc; Nash, Andrew; Yla-Herttuala, Seppo; Cao, Yihai; Watts, Ryan J.; Li, Xuri

    2009-01-01

    VEGF-B, a homolog of VEGF discovered a long time ago, has not been considered an important target in antiangiogenic therapy. Instead, it has received little attention from the field. In this study, using different animal models and multiple types of vascular cells, we revealed that although VEGF-B is dispensable for blood vessel growth, it is critical for their survival. Importantly, the survival effect of VEGF-B is not only on vascular endothelial cells, but also on pericytes, smooth muscle cells, and vascular stem/progenitor cells. In vivo, VEGF-B targeting inhibited both choroidal and retinal neovascularization. Mechanistically, we found that the vascular survival effect of VEGF-B is achieved by regulating the expression of many vascular prosurvival genes via both NP-1 and VEGFR-1. Our work thus indicates that the function of VEGF-B in the vascular system is to act as a “survival,” rather than an “angiogenic” factor and that VEGF-B inhibition may offer new therapeutic opportunities to treat neovascular diseases. PMID:19369214

  6. VEGF-A, cytoskeletal dynamics, and the pathological vascular phenotype

    International Nuclear Information System (INIS)

    Nagy, Janice A.; Senger, Donald R.

    2006-01-01

    Normal angiogenesis is a complex process involving the organization of proliferating and migrating endothelial cells (ECs) into a well-ordered and highly functional vascular network. In contrast, pathological angiogenesis, which is a conspicuous feature of tumor growth, ischemic diseases, and chronic inflammation, is characterized by vessels with aberrant angioarchitecture and compromised barrier function. Herein we review the subject of pathological angiogenesis, particularly that driven by vascular endothelial growth factor (VEGF-A), from a new perspective. We propose that the serious structural and functional anomalies associated with VEGF-A-elicited neovessels, reflect, at least in part, imbalances in the internal molecular cues that govern the ordered assembly of ECs into three dimensional vascular networks and preserve vessel barrier function. Adopting such a viewpoint widens the focus from solely on specific pro-angiogenic stimuli such as VEGF-A to include a key set of cytoskeletal regulatory molecules, the Rho GTPases, which are known to direct multiple aspects of vascular morphogenesis including EC motility, alignment, multi-cellular organization, as well as intercellular junction integrity. We offer this perspective to draw attention to the importance of endothelial cytoskeletal dynamics for proper neovascularization and to suggest new therapeutic strategies with the potential to improve the pathological vascular phenotype

  7. 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

  8. 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.

  9. Crosstalk between VEGF-A/VEGFR2 and GDNF/RET signaling pathways

    International Nuclear Information System (INIS)

    Tufro, Alda; Teichman, Jason; Banu, Nazifa; Villegas, Guillermo

    2007-01-01

    Vascular endothelial growth factor (VEGF-A) plays multiple roles in kidney development: stimulates cell proliferation, survival, tubulogenesis, and branching morphogenesis. However, the mechanism that mediates VEGF-A induced ureteric bud branching is unclear. Glial-derived neurotrophic factor (GDNF) signaling through tyrosine kinase c-RET is the major regulator of ureteric bud branching. Here we examined whether VEGF-A regulates RET signaling. We determined that ureteric bud-derived cells express the main VEGF-A signaling receptor, VEGFR2 and RET, by RT-PCR, immunoblotting, and immunocytochemistry. We show that the VEGF-A isoform VEGF 165 induces RET-tyr 1062 phosphorylation in addition to VEGFR2 autophosphorylation, that VEGF 165 and GDNF have additive effects on RET-tyr 1062 phosphorylation, and that VEGFR2 and RET co-immunoprecipitate. Functionally, VEGF 165 induces ureteric bud cell proliferation and branching morphogenesis. Similarly, in embryonic kidney explants VEGF 165 induces RET-tyr 1062 phosphorylation and upregulates GDNF. These findings provide evidence for a novel cooperative interaction between VEGFR2 and RET that mediates VEGF-A functions in ureteric bud cells

  10. VEGF-121 plasma level as biomarker for response to anti-angiogenetic therapy in recurrent glioblastoma.

    Science.gov (United States)

    Martini, Maurizio; de Pascalis, Ivana; D'Alessandris, Quintino Giorgio; Fiorentino, Vincenzo; Pierconti, Francesco; Marei, Hany El-Sayed; Ricci-Vitiani, Lucia; Pallini, Roberto; Larocca, Luigi Maria

    2018-05-10

    Vascular endothelial growth factor (VEGF) isoforms, particularly the diffusible VEGF-121, could play a major role in the response of recurrent glioblastoma (GB) to anti-angiogenetic treatment with bevacizumab. We hypothesized that circulating VEGF-121 may reduce the amount of bevacizumab available to target the heavier isoforms of VEGF, which are the most clinically relevant. We assessed the plasma level of VEGF-121 in a brain xenograft model, in human healthy controls, and in patients suffering from recurrent GB before and after bevacizumab treatment. Data were matched with patients' clinical outcome. In athymic rats with U87MG brain xenografts, the level of plasma VEGF-121 relates with tumor volume and it significantly decreases after iv infusion of bevacizumab. Patients with recurrent GB show higher plasma VEGF-121 than healthy controls (p = 0.0002) and treatment with bevacizumab remarkably reduced the expression of VEGF-121 in plasma of these patients (p = 0.0002). Higher plasma level of VEGF-121 was significantly associated to worse PFS and OS (p = 0.0295 and p = 0.0246, respectively). Quantitative analysis of VEGF-121 isoform in the plasma of patients with recurrent GB could be a promising predictor of response to anti-angiogenetic treatment.

  11. The significance of VEGF expression in stage II carcinoma of uterine cervix treated with definitive radiotherapy

    International Nuclear Information System (INIS)

    Park, Won; Choi, Yoon La; Huh, Seung Jae; Yoon, Sang Min; Park, Young Je; Nam, Hee Rim; Ahn, Yong Chan; Lim, Do Hoon; Park, Hee Chul

    2006-01-01

    We wanted to determine the clinical characteristics and prognosis according to the VEGF expression in stage II cervical carcinoma patients treated with definitive radiotherapy. We enrolled 31 patients who were diagnosed with cervical cancer from 1995 to 2003 at Samsumg Medical Center and their paraffin block tissue samples were available for study. The median age of the patients was 65 years. The mean tumor size was 4.1 cm (range: 1.2 ∼8.2 cm). Seven patients (22.6%) were suspected of having pelvic lymph node metastasis. An external beam irradiation dose of 45-56.4 Gy was administered to the whole pelvis with a 15 MV linear accelerator, and an additional 24 Gy was given to point A by HDR intracavitary brachytherapy. VEGF staining was defined as positive when more than 10% of the tumor cells were stained. The median follow-up duration was 58 months. A positive VEGF expression was observed in 21 patients (67.7%). There was no significant correlation between the VEGF expression and pelvic lymph node metastasis, tumor size and the response of radiotherapy. During follow-up, 7 patients had recurrence. The complete response rate was not significant between the VEGF (-) and VEGF(+) tumors. However, the VEGF(+) tumors showed a significantly higher recurrence rate in comparison with the VEGF(-) tumors (ρ = 0.040). The three year disease-free survival rates were 100% and 66.7%, respectively, for patients with VEGF(-) or VEGF(+) tumor (ρ = 0.047). The VEGF expression was a significant factor for recurrence and disease-free survival. However, the significance of the VEGF expression is still controversial because of the various definitions of VEGF expression and the mismatches of the clinical data in the previous studies

  12. 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

  13. Activation of erythropoietin receptors by Friend viral gp55 and by erythropoietin and down-modulation by the murine Fv-2r resistance gene

    International Nuclear Information System (INIS)

    Hoatlin, M.E.; Kozak, S.L.; Kabat, D.; Lilly, F.; Chakraborti, A.; Kozak, C.A.

    1990-01-01

    The leukemogenic membrane glycoprotein (gp55) encoded by Friend spleen focus-forming virus appears to bind to erythropoietin receptors (EpoR) to stimulate erythroblastosis. To directly compare the effects of gp55 with erythropoietin (Epo), the authors produced retrovirions that encode either gp55, Epo, or EpoR. After infection with EpoR virus, interleukin 3-dependent DA-3 cells bound 125 I-labeled Epo and grew without interleukin 3 in the presence of Epo. These latter cells, but not parental DA-3 cells, became factor-independent after superinfection either with Epo virus or with Friend spleen focus-forming virus. In addition, Epo virus caused a disease in mice that mimicked Friend erythroleukemia. Although Fv-2 r homozygotes are susceptible to all other retroviral diseases, they are resistant to both Epo viral and Friend viral erythroleukemia. These results indicate that both gp55 and Epo stimulate EpoR and that the Fv-2 gene encodes a protein that controls response to these ligands. However, the Fv-2 protein is not EpoR because the corresponding genes map to opposite ends of mouse chromosome 9. These results have important implications for understanding signal transduction by EpoR and the role of host genetic variation in controlling susceptibility to an oncogenic protein

  14. 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

    and that the contraction induced secretion of VEGF is partially mediated via adenosine acting on A(2B) adenosine receptors. Moreover, the contraction induced secretion of VEGF protein from muscle is dependent on both PKA and MAPK activation, but only the MAPK pathway appears to be adenosine dependent.......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 contraction caused secretion of VEGF (pcontraction induced secretion of VEGF protein was abolished by the A(2B) antagonist enprofyllin and markedly reduced by inhibition of PKA or MAPK. The results demonstrate that adenosine causes secretion of VEGF from human skeletal muscle cells...

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

    International Nuclear Information System (INIS)

    Garcia-Roman, Jonathan; Ibarra-Sanchez, Alfredo; Lamas, Monica; Gonzalez Espinosa, Claudia

    2010-01-01

    Research highlights: → Bone marrow-derived mast cells (BMMCs) secrete functional VEGF but do not degranulate after Cobalt chloride-induced hypoxia. → CoCl 2 -induced VEGF secretion in mast cells occurs by a Ca 2+ -insensitive but brefeldin A and Tetanus toxin-sensitive mechanism. → Trolox and N-acetylcysteine inhibit hypoxia-induced VEGF secretion but only Trolox inhibits FcεRI-dependent anaphylactic degranulation in mast cells. → 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 2 ) to analyze VEGF secretion in murine bone marrow-derived mast cells (BMMCs). We found that CoCl 2 promotes a sustained production of functional VEGF, able to induce proliferation of endothelial cells in vitro. CoCl 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 2 -induced VEGF secretion was observed in Fyn kinase-deficient BMMCs. Moreover, Fyn kinase was activated by CoCl 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-dependent Fyn kinase activation.

  16. Differential regulation of ANG2 and VEGF-A in human granulosa lutein cells by choriogonadotropin.

    Science.gov (United States)

    Pietrowski, D; Keck, C

    2004-04-01

    The growth and development of the corpus luteum after rupture of the follicle is a highly regulated process characterised by a rapid vascularization of the follicle surrounding granulosa cells. Vascularization is regulated by a large number of growth factors and cytokines whereas members of the angiopoietin family and VEGF-A are reported to play a principal role. The gonadotropic hormones luteinizing hormone and choriogonadotropin are reported to be essential for corpus luteum formation. In this study we investigated by RT PCR if the growth factors PGF, PDGF-A, PDGF-B, VEGF-A, VEGF-B, VEGF-C, VEGF-D, ANG1, ANG2, ANG3 and ANG4 are expressed in granulosa cells. We show the expression of VEGF-A, VEGF-B, PDGF-A, ANG1 and ANG2 in granulosa cells. Using RT-PCR and Real-Time PCR we demonstrate that angiopoietin 2 is downregulated in human granulosa cells in vitro after choriogonadotropin treatment whereas the expression of angiopoietin 1 is not significantly altered. The expression of VEGF on the RNA- and on the protein level was determined. It was shown that in granulosa cells VEGF is upregulated after choriogonadotropin treatment on the RNA level and that increasing concentrations of choriogonadotropin from 0 to 10 U/ml leads to an increasing amount of VEGF in the cell culture supernatants. The amount of VEGF in the supernatants reaches a plateau at 0.5 U/ml and is increased only slightly and not significantly after treatment of the cells with 10 U/ml choriogonadotropin compared to 0.5 U/ml. In total these findings suggests that in granulosa cells the mRNA of various growth factors is detectable by RT-PCR and that VEGF-A and ANG2 is regulated by the gonadotropic hormone choriogonadotropin. These findings may add impact on the hypothesis of choriogonadotropin as a novel angiogenic factor.

  17. 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

  18. 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.

  19. Radiolabeling of VEGF165 with 99mTc to evaluate VEGFR expression in tumor angiogenesis.

    Science.gov (United States)

    Galli, Filippo; Artico, Marco; Taurone, Samanta; Manni, Isabella; Bianchi, Enrica; Piaggio, Giulia; Weintraub, Bruce D; Szkudlinski, Mariusz W; Agostinelli, Enzo; Dierckx, Rudi A J O; Signore, Alberto

    2017-06-01

    Angiogenesis is the main process responsible for tumor growth and metastatization. The principal effector of such mechanism is the vascular endothelial growth factor (VEGF) secreted by cancer cells and other components of tumor microenvironment. Radiolabeled VEGF analogues may provide a useful tool to noninvasively image tumor lesions and evaluate the efficacy of anti-angiogenic drugs that block the VEGFR pathway. Aim of the present study was to radiolabel the human VEGF165 analogue with 99mTechnetium (99mTc) and to evaluate the expression of VEGFR in both cancer and endothelial cells in the tumor microenvironment. 99mTc-VEGF showed in vitro binding to HUVEC cells and in vivo to xenograft tumors in mice (ARO, K1 and HT29). By comparing in vivo data with immunohistochemical analysis of excised tumors we found an inverse correlation between 99mTc-VEGF165 uptake and VEGF histologically detected, but a positive correlation with VEGF receptor expression (VEGFR1). Results of our studies indicate that endogenous VEGF production by cancer cells and other cells of tumor microenvironment should be taken in consideration when performing scintigraphy with radiolabeled VEGF, because of possible false negative results due to saturation of VEGFRs.

  20. Alteration of protein expression pattern of vascular endothelial growth factor (VEGF) from soluble to cell-associated isoform during tumourigenesis

    International Nuclear Information System (INIS)

    Cressey, Ratchada; Wattananupong, Onusa; Lertprasertsuke, Nirush; Vinitketkumnuen, Usanee

    2005-01-01

    Vascular endothelial growth factor (VEGF) is a potent mitogen for endothelial cells, and its expression has been correlated with increased tumour angiogenesis. Although numerous publications dealing with the measurement of circulating VEGF for diagnostic and therapeutic monitoring have been published, the relationship between the production of tissue VEGF and its concentration in blood is still unclear. The aims of this study were to determine: 1) The expression pattern of VEGF isoforms at the protein level in colorectal and lung adenocarcinoma in comparison to the pattern in corresponding adjacent normal tissues 2) The relationship between the expression pattern of VEGF and total level of circulating VEGF in the blood to clarify whether the results of measuring circulating VEGF can be used to predict VEGF expression in tumour tissues. Ninety-four tissue samples were obtained from patients, 76 colorectal tumour tissues and 18 lung tumour tissues. VEGF protein expression pattern and total circulating VEGF were examined using western blot and capture ELISA, respectively. Three major protein bands were predominately detected in tumour samples with an apparent molecular mass under reducing conditions of 18, 23 and 26 kDa. The 18 kDa VEGF protein was expressed equally in both normal and colorectal tumour tissues and predominately expressed in normal tissues of lung, whereas the 23 and 26 kDa protein was only detected at higher levels in tumour tissues. The 18, 23 and 26 kDa proteins are believed to represent the VEGF 121 , the VEGF 165 and the VEGF 189 , respectively. There was a significant correlation of the expression of VEGF 165 with a smaller tumour size maximum diameter <5 cm (p < 0.05), and there was a significant correlation of VEGF 189 with advanced clinical stage of colorectal tumours. The measurement of total circulating VEGF in serum revealed that cancer patients significantly (p < 0.001) possessed a higher level of circulating VEGF (1081 ± 652 pg/ml in

  1. Exposure of chick embryos to cadmium changes the extra-embryonic vascular branching pattern and alters expression of VEGF-A and VEGF-R2

    Energy Technology Data Exchange (ETDEWEB)

    Gheorghescu, Anna Kaskova [School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4 (Ireland); Tywoniuk, Bartlomiej [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Complex and Adaptive Systems Laboratory, University College Dublin, Belfield, Dublin 4 (Ireland); Duess, Johannes [School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4 (Ireland); National Children' s Research Centre, Our Lady' s Children' s Hospital, Crumlin, Dublin 12 (Ireland); Buchete, Nicolae-Viorel, E-mail: buchete@ucd.ie [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Complex and Adaptive Systems Laboratory, University College Dublin, Belfield, Dublin 4 (Ireland); Thompson, Jennifer, E-mail: jennifer.thompson@ucd.ie [School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4 (Ireland)

    2015-11-15

    Cadmium (Cd) has several industrial applications, and is found in tobacco products, a notable source of human exposure. Vascular endothelial cells are key targets of Cd toxicity. Here, we aim to quantify the alteration to vascular branching pattern following Cd exposure in the chick extra-embryonic membrane (EEM) using fractal analysis, and explore molecular cues to angiogenesis such as VEGF-A and VEGF-R2 expression following Cd treatment. Chicken embryos were incubated for 60 h to Hamburger–Hamilton developmental stage 16–17, then explanted and treated with 50 μL of 50 μmol cadmium acetate (CdAc) or an equivalent volume of equimolar sodium acetate (NaAc). Images of embryos and their area vasculosa (AV) were captured and analyzed at 4 different time points (4, 8, 24 and 48 h) following treatment. Vascular branching in the AV was quantified using its fractal dimension (D{sub f}), estimated using a box counting method. Gallinaceous VEGF ELISA was used to measure the VEGF-A concentration in the EEM following treatment, with determination of the relative expression of VEGF-A and VEGF-R2 using quantitative real-time RT-PCR. Vascular branching increased monotonically in the control group at all time points. The anti-angiogenic effect of Cd exposure on the AV was reflected by a significant reduction in D{sub f} when compared with controls. D{sub f} was more markedly reduced in cultures with abnormal embryos. The expression of VEGF-A protein, and VEGF-A and VEGF-R2 mRNA were reduced in Cd-exposed EEMs. Both molecules contribute to growth, vessel sprouting and branching processes, which supports our findings using fractal analysis. - Highlights: • The chick area vasculosa was undersized in embryos exposed to 50 μM cadmium acetate. • Fractal dimension was reduced in the AV after Cd exposure, indicating decreased branching. • VEGF-A protein was decreased in Cd-treated extraembryonic membranes. • VEGF-A and VEGF-R2 mRNA was decreased in Cd-treated extraembryonic

  2. 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.

  3. Monitoring PAI-1 and VEGF Levels in 6 Human Squamous Cell Carcinoma Xenografts During Fractionated Irradiation

    International Nuclear Information System (INIS)

    Bayer, Christine; Kielow, Achim; Schilling, Daniela; Maftei, Constantin-Alin; Zips, Daniel; Yaromina, Ala; Baumann, Michael; Molls, Michael; Multhoff, Gabriele

    2012-01-01

    Purpose: Previous studies have shown that the plasminogen activator inhibitor type-1 (PAI-1) and vascular endothelial growth factor (VEGF) are regulated by hypoxia and irradiation and are involved in neoangiogenesis. The aim of this study was to determine in vivo whether changes in PAI-1 and VEGF during fractionated irradiation could predict for radiation resistance. Methods and Materials: Six xenografted tumor lines from human squamous cell carcinomas (HSCC) of the head and neck were irradiated with 0, 3, 5, 10, and 15 daily fractions of 2 Gy. The PAI-1 and VEGF antigen levels in tumor lysates were determined by enzyme-linked immunosorbent assay kits. The amounts of PAI-1 and VEGF were compared with the dose to cure 50% of tumors (TCD 50 ). Colocalization of PAI-1, pimonidazole (hypoxia), CD31 (endothelium), and Hoechst 33342 (perfusion) was examined by immunofluorescence. Results: Human PAI-1 and VEGF (hVEGF) expression levels were induced by fractionated irradiation in UT-SCC-15, UT-SCC-14, and UT-SCC-5 tumors, and mouse VEGF (msVEGF) was induced only in UT-SCC-5 tumors. High hVEGF levels were significantly associated with radiation sensitivity after 5 fractions (P=.021), and high msVEGF levels were significantly associated with radiation resistance after 10 fractions (P=.007). PAI-1 staining was observed in the extracellular matrix, the cytoplasm of fibroblast-like stroma cells, and individual tumor cells at all doses of irradiation. Colocalization studies showed PAI-1 staining close to microvessels. Conclusions: These results indicate that the concentration of tumor-specific and host-specific VEGF during fractionated irradiation could provide considerably divergent information for the outcome of radiation therapy.

  4. 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.

  5. A two-compartment model of VEGF distribution in the mouse.

    Directory of Open Access Journals (Sweden)

    Phillip Yen

    Full Text Available Vascular endothelial growth factor (VEGF is a key regulator of angiogenesis--the growth of new microvessels from existing microvasculature. Angiogenesis is a complex process involving numerous molecular species, and to better understand it, a systems biology approach is necessary. In vivo preclinical experiments in the area of angiogenesis are typically performed in mouse models; this includes drug development targeting VEGF. Thus, to quantitatively interpret such experimental results, a computational model of VEGF distribution in the mouse can be beneficial. In this paper, we present an in silico model of VEGF distribution in mice, determine model parameters from existing experimental data, conduct sensitivity analysis, and test the validity of the model. The multiscale model is comprised of two compartments: blood and tissue. The model accounts for interactions between two major VEGF isoforms (VEGF(120 and VEGF(164 and their endothelial cell receptors VEGFR-1, VEGFR-2, and co-receptor neuropilin-1. Neuropilin-1 is also expressed on the surface of parenchymal cells. The model includes transcapillary macromolecular permeability, lymphatic transport, and macromolecular plasma clearance. Simulations predict that the concentration of unbound VEGF in the tissue is approximately 50-fold greater than in the blood. These concentrations are highly dependent on the VEGF secretion rate. Parameter estimation was performed to fit the simulation results to available experimental data, and permitted the estimation of VEGF secretion rate in healthy tissue, which is difficult to measure experimentally. The model can provide quantitative interpretation of preclinical animal data and may be used in conjunction with experimental studies in the development of pro- and anti-angiogenic agents. The model approximates the normal tissue as skeletal muscle and includes endothelial cells to represent the vasculature. As the VEGF system becomes better characterized in

  6. 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.

  7. National Cooperative rHu Erythropoietin Study in patients with chronic renal failure--an interim report. The National Cooperative rHu Erythropoietin Study Group.

    Science.gov (United States)

    Levin, N W; Lazarus, J M; Nissenson, A R

    1993-08-01

    This second interim report of the National Cooperative rHu Erythropoietin Study presents data from 324 patients new to recombinant human erythropoietin (Epoetin alfa) who completed at least 12 months of study participation. Mean hematocrit levels increased to approximately 30% by month 3 in patients on hemodialysis (n = 293) and stabilized for the remainder of the study whether Epoetin alfa was administered by the intravenous (n = 250) or subcutaneous (n = 42) route. The intravenous dosage level ranged between 106.9 and 121.6 U/kg/wk; subcutaneous dosing ranged between 87.4 and 108.0 U/kg/wk; dosing levels in patients on peritoneal dialysis (n = 31) were similar, although there was a trend towards slightly higher hematocrit levels. Throughout the 12 months of the study, there was no relationship between blood pressure and either hematocrit level or Epoetin alfa dose. Approximately two thirds of the patients were receiving iron supplementation at any given time, and there was a trend towards the increased use of oral iron supplements. The incidence of adverse events in this cohort of patients was low throughout the study, and there was no relationship between the incidence of adverse events and either hematocrit level or Epoetin alfa dose. Based on an analysis of data from baseline to first follow-up, Epoetin alfa therapy resulted in improvement in several quality-of-life factors, most notable of which was vitality. Improvement occurred in all patient subgroups with some variability in the level and intensity of effect. Overall, these data demonstrate that Epoetin alfa therapy is safe and effective when used in a broad cross-section of patients on dialysis.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Skeletal myofiber VEGF regulates contraction-induced perfusion and exercise capacity but not muscle capillarity in adult mice.

    Science.gov (United States)

    Knapp, Amy E; Goldberg, Daniel; Delavar, Hamid; Trisko, Breanna M; Tang, Kechun; Hogan, Michael C; Wagner, Peter D; Breen, Ellen C

    2016-07-01

    A single bout of exhaustive exercise signals expression of vascular endothelial growth factor (VEGF) in the exercising muscle. Previous studies have reported that mice with life-long deletion of skeletal myofiber VEGF have fewer capillaries and a severe reduction in endurance exercise. However, in adult mice, VEGF gene deletion conditionally targeted to skeletal myofibers limits exercise capacity without evidence of capillary regression. To explain this, we hypothesized that adult skeletal myofiber VEGF acutely regulates skeletal muscle perfusion during muscle contraction. A tamoxifen-inducible skeletal myofiber-specific VEGF gene deletion mouse (skmVEGF-/-) was used to reduce skeletal muscle VEGF protein by 90% in adult mice. Three weeks after inducing deletion of the skeletal myofiber VEGF gene, skmVEGF-/- mice exhibited diminished maximum running speed (-10%, P Contraction-induced perfusion measured by optical imaging during a period of electrically stimulated muscle contraction was 85% lower in skmVEGF-/- than control mice. No evidence of capillary rarefication was detected in the soleus, gastrocnemius, and extensor digitorum longus (EDL) up to 8 wk after tamoxifen-induced VEGF ablation, and contractility and fatigue resistance of the soleus measured ex vivo were also unchanged. The force-frequency of the EDL showed a small right shift, but fatigue resistance did not differ between EDL from control and skmVEGF-/- mice. These data suggest myofiber VEGF is required for regulating perfusion during periods of contraction and may in this manner affect endurance capacity. Copyright © 2016 the American Physiological Society.

  9. 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...

  10. Cytoprotective effect of glutaraldehyde erythropoietin on HEK293 kidney cells after silver nanoparticle exposure

    Directory of Open Access Journals (Sweden)

    Sooklert K

    2016-02-01

    Full Text Available Kanidta Sooklert,1,2 Supreecha Chattong,3 Krissanapong Manotham,3 Chawikan Boonwong,1 I-yanut Klaharn,1 Depicha Jindatip,4 Amornpun Sereemaspun1,4 1Nanobiomedicine Laboratory, Department of Anatomy, Faculty of Medicine, 2Inter-Department Program of Biomedical Sciences, Faculty of Graduate School, Chulalongkorn University, 3Renal Unit, Department of Medicine, Lerdsin General Hospital, 4Department of Anatomy, Faculty of Medicine, Chulalongkorn University, Bangkok, ThailandAbstract: The toxic effects from exposure to silver nanoparticles (AgNPs, which are broadly present in many consumer products, have long raised concerns. Many studies have focused on the mechanisms of nanosilver, which cause toxicity in human cells, but little is known about prevention of this type of injury. This study investigated the in vitro effects of glutaraldehyde erythropoietin (GEPO, a cytoprotective compound derived from erythropoietin, in terms of cell protection against AgNP-induced injury. HEK293 cells were pretreated with or without GEPO before administration of AgNPs. The protective effects of GEPO in this cell line were assessed by the percentage of viable cells, alterations of cell morphology, and the proliferative capability of the cells. In addition, we assessed the role of GEPO in lowering cellular oxidative stress and regulating expression of the anti-apoptotic protein Bcl2. The results showed rescue effects on the percentage of viable and proliferative cells among GEPO pretreated cells. Pretreatment with GEPO maintained the normal cell shape and ultrastructural morphology. Moreover, GEPO reduced the generation of reactive oxygen species in cells and activated expression of Bcl2, which are the major mechanisms in protection against cellular toxicity induced by AgNPs. In conclusion, our study showed that the cytotoxic effects from exposure to AgNPs can be prevented by GEPO. Keywords: glutaraldehyde erythropoietin, silver nanoparticles, cytoprotection

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

    International Nuclear Information System (INIS)

    Dunst, J.

    2004-01-01

    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 ∝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.)

  12. Effects of low-dose recombinant human erythropoietin treatment on cognitive performance

    DEFF Research Database (Denmark)

    Viuff, Søren Lundgaard; Plenge, Ulla; Belhage, Bo

    2017-01-01

    , NUFI or self-reported results between the groups. CONCLUSIONS: In this small study, we found no significant effect of low-dose or micro-dose rhEpo on visual attention, cognitive performance in complex cognitive tasks or self-experienced cognitive performance compared with placebo. FUNDING: The Aase......INTRODUCTION: High-dose recombinant human erythropoietin (rhEpo) has been shown to improve cognitive performance in both healthy volunteers and in patients suffering from diseases affecting the brain. The aim of this study was to examine whether administration of low-dose and even micro-dose rh...

  13. Effects of low-dose recombinant human erythropoietin treatment on cognitive performance

    DEFF Research Database (Denmark)

    Viuff, Søren Lundgaard; Plenge, Ulla; Belhage, Bo

    2017-01-01

    -reported results between the groups. Conclusions: In this small study, we found no significant effect of low-dose or micro-dose rhEpo on visual attention, cognitive performance in complex cognitive tasks or self-experienced cognitive performance compared with placebo. Funding: The Aase and Ejnar Danielsen......Introduction: High-dose recombinant human erythropoietin (rhEpo) has been shown to improve cognitive performance in both healthy volunteers and in patients suffering from diseases affecting the brain. The aim of this study was to examine whether administration of low-dose and even micro-dose rh...

  14. Immunoreactive erythropoietin concentrations in neonatal rats and the effects of hypoxia

    International Nuclear Information System (INIS)

    Clemons, G.K.; Fitzsimmons, S.L.; DeManincor, D.

    1987-01-01

    We attempted to find answers to what are the circulating, hepatic and renal erythropoietin (Ep) levels in normal rat neonates measured daily through the first three weeks of life and when they attain sexual maturity, how are these Ep levels altered by exposure to hypoxia, and whether can it be transferred to the nursing neonatal animals? Since we established earlier that in the fetal rat the liver is the main Ep producing tissue, we attempted to determine the age at which the switch from liver to kidney occurred in both the normal and the hypoxic neonatal rat. 2 figs

  15. 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...... subjects. After an injection in the evening, urine and plasma samples were collected the following morning. Half of the subjects then drank a bolus of water and new samples were collected 80 min later. Interestingly, rhEPO was detected in 100% of the samples even after water ingestion. A second similar...

  16. [Renal cell carcinoma producing erythrocytosis due to inappropriate production of erythropoietin].

    Science.gov (United States)

    Villanueva-Gimeno, M M; Vicario-Bermúdez, J M; Fonseca-López, Ch; Caballero-Castro, J P; Zabala-López, S I; Sánchez-Elipe, M A; González-Gómez, N

    2013-01-01

    Erythrocytosis, or polycythaemia, is an increase, in absolute terms, of the erythrocyte mass. The most common solid tumour related to this phenomenon is renal cell carcinoma, which can produce erythrocytosis by increasing erythropoietin production. About 30% of symptomatic renal cell carcinomas are diagnosed due to the appearance of a paraneoplastic syndrome. Polycythaemia is one of these. Surgery, (radical or partial nephrectomy), is the treatment of choice in renal cell carcinoma and helps to keep the erythrocytosis situation under control. Copyright © 2011 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

  17. Erythropoietin as an add-on treatment for cognitive side effects of electroconvulsive therapy

    DEFF Research Database (Denmark)

    Schmidt, Lejla Sjanic; Petersen, Jeff Zarp; Vinberg, Maj

    2018-01-01

    trial investigates (1) whether short-term add-on treatment with erythropoietin (EPO) can reduce the cognitive side -effects of ECT and (2) whether such effects are long-lasting. Further, structural and functional magnetic resonance imaging (MRI) will be used to explore the neural underpinnings...... cognitive benefits of EPO are investigated with structural and functional MRI after the final EPO/saline infusion. The primary outcome is change from baseline to after EPO treatment (3 days after eight ECT sessions) in a cognitive composite score spanning attention, psychomotor speed, and executive...... of covariance. Functional MRI data will be preprocessed and analyzed using the FMRIB Software Library....

  18. 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

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

    Directory of Open Access Journals (Sweden)

    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

  20. 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...

  1. VEGF-C gene therapy augments postnatal lymphangiogenesis and ameliorates secondary lymphedema

    Science.gov (United States)

    Yoon, Young-sup; Murayama, Toshinori; Gravereaux, Edwin; Tkebuchava, Tengiz; Silver, Marcy; Curry, Cynthia; Wecker, Andrea; Kirchmair, Rudolf; Hu, Chun Song; Kearney, Marianne; Ashare, Alan; Jackson, David G.; Kubo, Hajime; Isner, Jeffrey M.; Losordo, Douglas W.

    2003-01-01

    Although lymphedema is a common clinical condition, treatment for this disabling condition remains limited and largely ineffective. Recently, it has been reported that overexpression of VEGF-C correlates with increased lymphatic vessel growth (lymphangiogenesis). However, the effect of VEGF-C–induced lymphangiogenesis on lymphedema has yet to be demonstrated. Here we investigated the impact of local transfer of naked plasmid DNA encoding human VEGF-C (phVEGF-C) on two animal models of lymphedema: one in the rabbit ear and the other in the mouse tail. In a rabbit model, following local phVEGF-C gene transfer, VEGFR-3 expression was significantly increased. This gene transfer led to a decrease in thickness and volume of lymphedema, improvement of lymphatic function demonstrated by serial lymphoscintigraphy, and finally, attenuation of the fibrofatty changes of the skin, the final consequences of lymphedema. The favorable effect of phVEGF-C on lymphedema was reconfirmed in a mouse tail model. Immunohistochemical analysis using lymphatic-specific markers: VEGFR-3, lymphatic endothelial hyaluronan receptor-1, together with the proliferation marker Ki-67 Ab revealed that phVEGF-C transfection potently induced new lymphatic vessel growth. This study, we believe for the first time, documents that gene transfer of phVEGF-C resolves lymphedema through direct augmentation of lymphangiogenesis. This novel therapeutic strategy may merit clinical investigation in patients with lymphedema. PMID:12618526

  2. 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

  3. 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 ...

  4. Activation of Protease-Activated Receptor 2 Induces VEGF Independently of HIF-1

    DEFF Research Database (Denmark)

    Rasmussen, J.G.; Riis, Simone Elkjær; Frøbert, O.

    2012-01-01

    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 fact...

  5. 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...

  6. Radiolabeling of VEGF(165) with Tc-99m to evaluate VEGFR expression in tumor angiogenesis

    NARCIS (Netherlands)

    Galli, Filippo; Artico, Marco; Taurone, Samanta; Manni, Isabella; Bianchi, Enrica; Piaggio, Giulia; Weintraub, Bruce D.; Szkudlinski, Mariusz W.; Agostinelli, Enzo; Dierckx, Rudi A. J. O.; Signore, Alberto

    Angiogenesis is the main process responsible for tumor growth and metastatization. The principal effector of such mechanism is the vascular endothelial growth factor (VEGF) secreted by cancer cells and other components of tumor microenvironment. Radiolabeled VEGF analogues may provide a useful tool

  7. Interplay between VEGF and Nrf2 regulates angiogenesis due to intracranial venous hypertension.

    Science.gov (United States)

    Li, Liwen; Pan, Hao; Wang, Handong; Li, Xiang; Bu, Xiaomin; Wang, Qiang; Gao, Yongyue; Wen, Guodao; Zhou, Yali; Cong, Zixiang; Yang, Youqing; Tang, Chao; Liu, Zhengwei

    2016-11-21

    Venous hypertension(VH) plays an important role in the pathogenesis of cerebral arteriovenous malformations (AVMs) and is closely associated with the HIF-1α/VEGF signaling pathway. Nuclear factor erythroid 2-related factor 2(Nrf2) significantly influences angiogenesis; however, the interplay between Nrf2 and VEGF under VH in brain AVMs remains unclear. Therefore, our study aimed to investigate the interplay between Nrf2 and VEGF due to VH in brain AVMs. Immunohistochemistry indicated that Nrf2 and VEGF were highly expressed in human brain AVM tissues. In vivo, we established a VH model in both wild-type (WT) and siRNA-mediated Nrf2 knockdown rats. VH significantly increased the expression of Nrf2 and VEGF. Loss of Nrf2 markedly inhibited the upregulation of VEGF, as determined by Western blot analysis and qRT-PCR. In vitro, primary brain microvascular endothelial cells (BMECs) were isolated from WT and Nrf2 -/- mice, and a VEGF-Nrf2 positive feed-back loop was observed in BMECs. By trans well assay and angiogenesis assay, Nrf2 knockout significantly inhibited the migration and vascular tube formation of BMECs. These findings suggest that the interplay between Nrf2 and VEGF can contribute to VH-induced angiogenesis in brain AVMs pathogenesis.

  8. 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...

  9. 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...

  10. 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...

  11. Molecular characterization of EG-VEGF-mediated angiogenesis: differential effects on microvascular and macrovascular endothelial cells.

    Science.gov (United States)

    Brouillet, Sophie; Hoffmann, Pascale; Benharouga, Mohamed; Salomon, Aude; Schaal, Jean-Patrick; Feige, Jean-Jacques; Alfaidy, Nadia

    2010-08-15

    Endocrine gland derived vascular endothelial growth factor (EG-VEGF) also called prokineticin (PK1), has been identified and linked to several biological processes including angiogenesis. EG-VEGF is abundantly expressed in the highest vascularized organ, the human placenta. Here we characterized its angiogenic effect using different experimental procedures. Immunohistochemistry was used to localize EG-VEGF receptors (PROKR1 and PROKR2) in placental and umbilical cord tissue. Primary microvascular placental endothelial cell (HPEC) and umbilical vein-derived macrovascular EC (HUVEC) were used to assess its effects on proliferation, migration, cell survival, pseudovascular organization, spheroid sprouting, permeability and paracellular transport. siRNA and neutralizing antibody strategies were used to differentiate PROKR1- from PROKR2-mediated effects. Our results show that 1) HPEC and HUVEC express both types of receptors 2) EG-VEGF stimulates HPEC's proliferation, migration and survival, but increases only survival in HUVECs. and 3) EG-VEGF was more potent than VEGF in stimulating HPEC sprout formation, pseudovascular organization, and it significantly increases HPEC permeability and paracellular transport. More importantly, we demonstrated that PROKR1 mediates EG-VEGF angiogenic effects, whereas PROKR2 mediates cellular permeability. Altogether, these data characterized angiogenic processes mediated by EG-VEGF, depicted a new angiogenic factor in the placenta, and suggest a novel view of the regulation of angiogenesis in placental pathologies.

  12. RELATIONSHIP BETWEEN THE PROANGIOGENIC ROLE OF EG-VEGF, CLINICOPATHOLOGICAL CHARACTERISTICS AND SURVIVAL IN TUMORAL OVARY.

    Science.gov (United States)

    Lozneanu, Ludmila; Avădănei, Roxana; Cîmpean, Anca Maria; Giuşcă, Simona Eliza; Amălinei, Cornelia; Căruntu, Irina-Draga

    2015-01-01

    To prove the presence of EG-VEGF in tumor ovary and to analyze its involvement in the ovarian carcinogenesis, as promoter of angiogenesis, in relationship with the clinicopathological prognostic factors and survival. The study group comprises tumor tissue specimens from 50 cases of surgically treated ovarian cancer that were immunohistochemically investigated. A scoring system based on the percentage of positive cells and the intensity of staining was applied for the semiquantitative assessment of EG-VEGF, as negative or positive. Statistics involved χ2 test, and Kaplan-Meier and log-rank test. EG-VEGF was positive in 35 cases (70%) and negative in 15 cases (30%). Our data confirmed the predominance of EG-VEGF positivity in the serous subiype as compared to endometrioid and clear cell subtypes, and its absence in mucinous subtype. Moreover, we demonstrated that EG-VEGF is overexpressed mainly in high-grade ovarian carcinomas (type II) than in low-grade ones. Significant differences were registered between the EG-VEGF positive or negative expression and tumor stage and histological subtypes, respectively. Survival analysis showed no differences in patient's survival and EG-VEGF positive and negative cases. The analysis of EG-VEGF expression in ovarian tumors points out the relationship between the enhanced potential for tumor angiogenesis and the tumor aggressivity.

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

    African Journals Online (AJOL)

    Yomi

    2012-01-16

    Jan 16, 2012 ... recombinant human VEGF165 (rhVEGF165) protein in CHO cells. ... The PCR program consisted of a denaturation step at 95°C for 3 min, then 25 cycles at ... PCR product for template and two oligos introduced at one end for.

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

    Directory of Open Access Journals (Sweden)

    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

  15. Neutralizing VEGF bioactivity with a soluble chimeric VEGF receptor protein flt (1-3) IGG inhibits testosterone stimulated prostate growth in castrated mice

    International Nuclear Information System (INIS)

    Hammarsten, P.; Lissbrant, E.; Lissbrant, I.-F.; Haeggstroem-Rudolfsson, S.; Bergh, A.; Ferrara, N.

    2003-01-01

    Recent studies show that testosterone stimulated growth of the glandular tissue in the ventral prostate in adult castrated rats is preceded by increased epithelial VEGF synthesis, endothelial cell proliferation, vascular growth, and increased blood flow. These observations suggest that testosterone stimulated prostate growth could be angiogenesis dependent, and that VEGF could play a central role in this. To test this hypothesis adult male mice were castrated and after one week treated with testosterone and vehicle, or with testosterone and a soluble chimeric VEGF-receptor flt(1-3)IgG protein. Treatment with testosterone markedly increased endothelial cell proliferation, vascular volume and organ weight in the ventral prostate lobe in the vehicle groups, but these responses were inhibited but not fully prevented by anti-VEGF treatment. The testosterone stimulated increase in epithelial cell proliferation was unaffected by flt(1-3)IgG, but endothelial and epithelial cell apoptosis were increased in the anti-VEGF compared to the vehicle treated group. This study, together with our previous observations, suggest that testosterone stimulates vascular growth in the ventral prostate lobe indirectly by increasing epithelial VEGF synthesis and that this is a necessary component in testosterone stimulated prostate growth

  16. Effects of antibodies to EG-VEGF on angiogenesis in the chick embryo chorioallantoic membrane.

    Science.gov (United States)

    Feflea, Stefana; Cimpean, Anca Maria; Ceausu, Raluca Amalia; Gaje, Pusa; Raica, Marius

    2012-01-01

    Endocrine gland-related vascular endothelial growth factor (EG-VEGF), is an angiogenic factor specifically targeting endothelial cells derived from endocrine tissues. The inhibition of the EG-VEGF/prokineticin receptor pathway could represent a selective antiangiogenic and anticancer strategy. to evaluate the impact of an antibody to EG-VEGF on the rapidly growing capillary plexus of the chick embryo chorioallantoic membrane (CAM). The in ovo CAM assay was performed for the humanized EG-VEGF antibody. Hemorrhagic damage was induced in the capillaries, which led to early death of the embryos. Upon morphological staining, there was evidence of vascular disruption and extravasation of red blood cells in the chorion. Signs of vacuolization of the covering epithelium were also observed. Blocking endogenous EG-VEGF might represent a valuable approach of impairing or inhibiting angiogenesis in steroidogenic-derived embryonic tissues.

  17. Acute Podocyte Vascular Endothelial Growth Factor (VEGF-A) Knockdown Disrupts alphaVbeta3 Integrin Signaling in the Glomerulus

    Science.gov (United States)

    Veron, Delma; Villegas, Guillermo; Aggarwal, Pardeep Kumar; Bertuccio, Claudia; Jimenez, Juan; Velazquez, Heino; Reidy, Kimberly; Abrahamson, Dale R.; Moeckel, Gilbert; Kashgarian, Michael; Tufro, Alda

    2012-01-01

    Podocyte or endothelial cell VEGF-A knockout causes thrombotic microangiopathy in adult mice. To study the mechanism involved in acute and local injury caused by low podocyte VEGF-A we developed an inducible, podocyte-specific VEGF-A knockdown mouse, and we generated an immortalized podocyte cell line (VEGFKD) that downregulates VEGF-A upon doxycycline exposure. Tet-O-siVEGF:podocin-rtTA mice express VEGF shRNA in podocytes in a doxycycline-regulated manner, decreasing VEGF-A mRNA and VEGF-A protein levels in isolated glomeruli to ∼20% of non-induced controls and urine VEGF-A to ∼30% of control values a week after doxycycline induction. Induced tet-O-siVEGF:podocin-rtTA mice developed acute renal failure and proteinuria, associated with mesangiolysis and microaneurisms. Glomerular ultrastructure revealed endothelial cell swelling, GBM lamination and podocyte effacement. VEGF knockdown decreased podocyte fibronectin and glomerular endothelial alphaVbeta3 integrin in vivo. VEGF receptor-2 (VEGFR2) interacts with beta3 integrin and neuropilin-1 in the kidney in vivo and in VEGFKD podocytes. Podocyte VEGF knockdown disrupts alphaVbeta3 integrin activation in glomeruli, detected by WOW1-Fab. VEGF silencing in cultured VEGFKD podocytes downregulates fibronectin and disrupts alphaVbeta3 integrin activation cell-autonomously. Collectively, these studies indicate that podocyte VEGF-A regulates alphaVbeta3 integrin signaling in the glomerulus, and that podocyte VEGF knockdown disrupts alphaVbeta3 integrin activity via decreased VEGFR2 signaling, thereby damaging the three layers of the glomerular filtration barrier, causing proteinuria and acute renal failure. PMID:22808199

  18. VEGF as a Survival Factor in Ex Vivo Models of Early Diabetic Retinopathy.

    Science.gov (United States)

    Amato, Rosario; Biagioni, Martina; Cammalleri, Maurizio; Dal Monte, Massimo; Casini, Giovanni

    2016-06-01

    Growing evidence indicates neuroprotection as a therapeutic target in diabetic retinopathy (DR). We tested the hypothesis that VEGF is released and acts as a survival factor in the retina in early DR. Ex vivo mouse retinal explants were exposed to stressors similar to those characterizing DR, that is, high glucose (HG), oxidative stress (OS), or advanced glycation end-products (AGE). Neuroprotection was provided using octreotide (OCT), a somatostatin analog, and pituitary adenylate cyclase activating peptide (PACAP), two well-documented neuroprotectants. Data were obtained with real-time RT-PCR, Western blot, ELISA, and immunohistochemistry. Apoptosis was induced in the retinal explants by HG, OS, or AGE treatments. At the same time, explants also showed increased VEGF expression and release. The data revealed that VEGF is released shortly after exposure of the explants to stressors and before the level of cell death reaches its maximum. Retinal cell apoptosis was inhibited by OCT and PACAP. At the same time, OCT and PACAP also reduced VEGF expression and release. Vascular endothelial growth factor turned out to be a protective factor for the stressed retinal explants, because inhibiting VEGF with a VEGF trap further increased cell death. These data show that protecting retinal neurons from diabetic stress also reduces VEGF expression and release, while inhibiting VEGF leads to exacerbation of apoptosis. These observations suggest that the retina in early DR releases VEGF as a prosurvival factor. Neuroprotective agents may decrease the need of VEGF production by the retina, therefore limiting the risk, in the long term, of pathologic angiogenesis.

  19. Role of EG-VEGF in human placentation: Physiological and pathological implications.

    Science.gov (United States)

    Hoffmann, Pascale; Saoudi, Yasmina; Benharouga, Mohamed; Graham, Charles H; Schaal, Jean-Patrick; Mazouni, Chafika; Feige, Jean-Jacques; Alfaidy, Nadia

    2009-08-01

    Pre-eclampsia (PE), the major cause of maternal morbidity and mortality, is thought to be caused by shallow invasion of the maternal decidua by extravillous trophoblasts (EVT). Data suggest that a fine balance between the expressions of pro- and anti-invasive factors might regulate EVT invasiveness. Recently, we showed that the expression of the new growth factor endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is high in early pregnancy but falls after 11 weeks, suggesting an essential role for this factor in early pregnancy. Using human villous explants and HTR-8/SVneo, a first trimester extravillous trophoblast cell line, we showed differential expression of EG-VEGF receptors, PKR1 and PKR2, in the placenta and demonstrated that EG-VEGF inhibits EVT migration, invasion and tube-like organisation. EG-VEGF inhibitory effect on invasion was supported by a decrease in matrix metalloproteinase (MMP)-2 and MMP-9 production. Interference with PKR2 expression, using specific siRNAs, reversed the EG-VEGF-induced inhibitory effects. Furthermore, we determined EG-VEGF circulating levels in normal and PE patients. Our results showed that EG-VEGF levels were highest during the first trimester of pregnancy and decreased thereafter to non-pregnant levels. More important, EG-VEGF levels were significantly elevated in PE patients compared with age-matched controls. These findings identify EG-VEGF as a novel paracrine regulator of trophoblast invasion. We speculate that a failure to correctly down-regulate placental expression of EG-VEGF at the end of the first trimester of pregnancy might lead to PE.

  20. The endothelial adaptor molecule TSAd is required for VEGF-induced angiogenic sprouting through junctional c-Src activation

    NARCIS (Netherlands)

    Gordon, Emma J; Fukuhara, Daisuke; Weström, Simone; Padhan, Narendra; Sjöström, Elisabet O; van Meeteren, Laurens|info:eu-repo/dai/nl/299142353; He, Liqun; Orsenigo, Fabrizio; Dejana, Elisabetta; Bentley, Katie; Spurkland, Anne; Claesson-Welsh, Lena

    2016-01-01

    Activation of vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) by VEGF binding is critical for vascular morphogenesis. In addition, VEGF disrupts the endothelial barrier by triggering the phosphorylation and turnover of the junctional molecule VE-cadherin, a process mediated by the

  1. Perioperative erythropoietin protects the CNS against ischemic lesions in patients after open heart surgery.

    Science.gov (United States)

    Lakič, Nikola; Mrak, Miha; Šušteršič, Miha; Rakovec, Peter; Bunc, Matjaž

    2016-12-01

    The aim of this study was to establish erythropoietin as a protective factor against brain ischemia during open heart surgery. A total of 36 consecutive patients scheduled for revascularization heart surgery were included in the study. Of the patients 18 received 3 intravenous doses of recombinant human erythropoietin (rHuEpo, 24,000 IU) and 18 patients received a placebo. Magnetic resonance imaging (MRI) to detect new brain ischemic lesions was performed. Additionally, S100A, S100B, neuron-specific enolase A and B (NSE-A and B) and the concentration of antibodies against N‑methyl-D-aspartate receptors (NMDAR) to identify new neurological complications were determined. Patients who received rHuEpo showed no postoperative ischemic changes in the brain on MRI images. In the control group 5 (27.8 %) new ischemic lesions were found. The NMDAR antibody concentration, S100A, S100B and NSE showed no significant differences between the groups for new cerebral ischemia. High levels of lactate before and after external aortic compression (p = 0.022 and p = 0.048, respectively) and duration of operation could predict new ischemic lesions (p = 0.009). The addition of rHuEpo reduced the formation of lesions detectable by MRI in the brain and could be used clinically as neuroprotection in cardiac surgery.

  2. Anemia in kidney transplants without erythropoietic agents: levels of erythropoietin and iron parameters.

    Science.gov (United States)

    Florit, E A; Hadad, F; Rodriguez Cubillo, B; De la Flor, J C; Valga, F; Perez Flores, I; Calvo Romero, N; Valero San Cecilio, R; Barrientos Guzman, A; Sanchez Fructuoso, A

    2012-11-01

    To study the association between hemoglobin, endogenous erythropoietin (EPO) levels and ferric parameters in kidney recipients not treated with EPO-stimulating agents. Transverse study of 219 kidney transplant outpatients. The median time after transplantation was 54 months (P(25-75), 23-107). We assessed blood counts, ferric parameters, EPO levels, renal function (MDRD-4), and adjuvant treatment. We performed a linear regression analysis to predict hemoglobin. Median EPO values were 14.05 mUI/mL (P(25-75) = 10.2-19.7). Applying the formulas described by Beguin, kidney transplant recipients showed a low observed/expected ratio of erythropoietin and of transferrin. Considering anemia to be an hemoglobin of calculate hemoglobin was: hemoglobin = 11829-0909 log (EPG level) - 0455 (if female) + 0.010 0.013 transferrin + 0.013 creatinine clearance (r = .424, P < .001). Treatment with ACEI and/or ARBs seemed to produce a defect in the synthesis of EPO, while those treated with mTORi, a hyporesponsive state. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Neurobehavioral and cytotoxic effects of vanadium during oligodendrocyte maturation: a protective role for erythropoietin.

    Science.gov (United States)

    Mustapha, Oluwaseun; Oke, Bankole; Offen, Nils; Sirén, Anna-Leena; Olopade, James

    2014-07-01

    Vanadium exposure has been known to lead to lipid peroxidation, demyelination and oligodendrocytes depletion. We investigated behaviour and glial reactions in juvenile mice after early neonatal exposure to vanadium, and examined the direct effects of vanadium in oligodendrocyte progenitor cultures from embryonic mice. Neonatal pups exposed to vanadium via lactation for 15 and 22 days all had lower body weights. Behavioural tests showed in most instances a reduction in locomotor activity and negative geotaxis. Brain analyses revealed astrocytic activation and demyelination in the vanadium exposed groups compared to the controls. In cell culture, exposure of oligodendrocytes to 300 μM sodium metavanadate significantly increased cell death. Expression of the oligodendrocyte specific proteins, 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) and oligodendrocyte specific protein (OSP/Claudin) were reduced upon vanadium treatment while simultaneous administration of erythropoietin (EPO; 4-12 U/ml) counteracted vanadium-toxicity. The data suggest that oligodendrocyte damage may explain the increased vulnerability of the juvenile brain to vanadium and support a potential for erythropoietin as a protective agent against vanadium-toxicity during perinatal brain development and maturation. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. The effect of erythropoietin on calcium levels during hypoxia reoxygenation injury in rats

    Directory of Open Access Journals (Sweden)

    Constantinos Tsompos

    2016-04-01

    Full Text Available This experimental study examined the effect of erythropoietin (Epo on rat model and particularly in a hypoxia-reoxygenation protocol. The effect of that molecule was studied biochemically using blood mean calcium levels (Ca++. Forty rats of mean weight 247.7 g were used in the study. Ca++ levels were measured at 60 min (groups A and C and at 120 min (groups B and D of reoxygenation. Erythropoietin was administered only in groups C and D. Epo administration non-significantly decreased the Ca++ levels by 0.56%±1.13% (P=0.5761. Reoxygenation time non-significantly increased the Ca++ levels by 0.65%±1.12% (P=0.5281. However, Epo administration and reoxygenation time together non-significantly decreased the Ca++ levels by 0.34%±0.68% (P=0.6095. Epo administration whether it interacted or not with reoxygenation time had non-significant decreasing short-term effects on calcium levels. Perhaps, a longer study time than 2 h or a higher Epo dose may reveal more significant effects.

  5. 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.

  6. Investigation of Genetic Disturbances in Oxygen Sensing and Erythropoietin Signaling Pathways in Cases of Idiopathic Erythrocytosis

    Directory of Open Access Journals (Sweden)

    Carla Luana Dinardo

    2013-01-01

    Full Text Available Background. Idiopathic erythrocytosis is the term reserved for cases with unexplained origins of abnormally increased hemoglobin after initial investigation. Extensive molecular investigation of genes associated with oxygen sensing and erythropoietin signaling pathways, in those cases, usually involves sequencing all of their exons and it may be time consuming. Aim. To perform a strategy for molecular investigation of patients with idiopathic erythrocytosis regarding oxygen sensing and erythropoietin signaling pathways. Methods. Samples of patients with idiopathic erythrocytosis were evaluated for the EPOR, VHL, PHD2, and HIF-2α genes using bidirectional sequencing of their hotspots. Results. One case was associated with HIF-2α mutation. Sequencing did not identify any pathogenic mutation in 4 of 5 cases studied in any of the studied genes. Three known nonpathogenic polymorphisms were found (VHL p.P25L, rs35460768; HIF-2α p.N636N, rs35606117; HIF-2α p.P579P, rs184760160. Conclusion. Extensive molecular investigation of cases considered as idiopathic erythrocytosis does not frequently change the treatment of the patient. However, we propose a complementary molecular investigation of those cases comprising genes associated with erythrocytosis phenotype to meet both academic and genetic counseling purposes.

  7. Effects of Erythropoietin Administration on Adrenal Glands of Landrace/Large White Pigs after Ventricular Fibrillation

    Directory of Open Access Journals (Sweden)

    Armando Faa

    2016-01-01

    Full Text Available Aim. To evaluate the effects of erythropoietin administration on the adrenal glands in a swine model of ventricular fibrillation and resuscitation. Methods. Ventricular fibrillation was induced via pacing wire forwarded into the right ventricle in 20 female Landrace/Large White pigs, allocated into 2 groups: experimental group treated with bolus dose of erythropoietin (EPO and control group which received normal saline. Cardiopulmonary resuscitation (CPR was performed immediately after drug administration as per the 2010 European Resuscitation Council (ERC guidelines for Advanced Life Support (ALS until return of spontaneous circulation (ROSC or death. Animals who achieved ROSC were monitored, mechanically ventilated, extubated, observed, and euthanized. At necroscopy, adrenal glands samples were formalin-fixed, paraffin-embedded, and routinely processed. Sections were stained with hematoxylin-eosin. Results. Oedema and apoptosis were the most frequent histological changes and were detected in all animals in the adrenal cortex and in the medulla. Mild and focal endothelial lesions were also detected. A marked interindividual variability in the degree of the intensity of apoptosis and oedema at cortical and medullary level was observed within groups. Comparing the two groups, higher levels of pathological changes were detected in the control group. No significant difference between the two groups was observed regarding the endothelial changes. Conclusions. In animals exposed to ventricular fibrillation, EPO treatment has protective effects on the adrenal gland.

  8. Hemoglobin and hematocrit at the end of hemodialysis: a better way to adjust erythropoietin dose?

    Science.gov (United States)

    Rangel, Erika B; Andreoli, Maria Claudia; Matos, Ana Cristina C; Guimarães-Souza, Nadia K; Mallet, Ana Cláudia; Carneiro, Fabiana D; Santos, Bento C

    2010-04-01

    A severe disadvantage of administration of recombinant human erythropoietin to hemodialysis patients has been reported. A significant correlation has been shown with hemoglobin values determined online by use of the blood volume monitor (BVM) and by laboratory measurement. Online hemoglobin and hematocrit were measured by use of the BVM during hemodialysis session. Data were analyzed by t test and statistical significance was defined as a P of hemoglobin and hematocrit from 11.6 +/- 1.9 to 13.9 +/- 2.4 g/dL (17.4 +/- 7.1%, P = 0.02) and from 34.4 +/- 6.8 to 42 +/- 8.3% (20.6 +/- 8.8%, P = 0.022), respectively, were observed from the beginning to the end of dialysis. We hypothesize that a new strategy for adjusting erythropoietin dose may be based on hemoglobin and hematocrit values evaluated at the end of hemodialysis, when patients are no longer hypervolemic. Inadvertent high levels of hemoglobin could be one explanation why patients present higher rates of cardiovascular and access-related events, especially when monitored online by use of the BVM to achieve the dry weight.

  9. Suppression of Retinal Neovascularization in vivo by Inhibition of Vascular Endothelial Growth Factor (VEGF) Using Soluble VEGF-Receptor Chimeric Proteins

    Science.gov (United States)

    Aiello, Lloyd Paul; Pierce, Eric A.; Foley, Eliot D.; Takagi, Hitoshi; Chen, Helen; Riddle, Lavon; Ferrara, Napoleone; King, George L.; Smith, Lois E. H.

    1995-11-01

    The majority of severe visual loss in the United States results from complications associated with retinal neovascularization in patients with ischemic ocular diseases such as diabetic retinopathy, retinal vein occlusion, and retinopathy of prematurity. Intraocular expression of the angiogenic protein vascular endothelial growth factor (VEGF) is closely correlated with neovascularization in these human disorders and with ischemia-induced retinal neovascularization in mice. In this study, we evaluated whether in vivo inhibition of VEGF action could suppress retinal neovascularization in a murine model of ischemic retinopathy. VEGF-neutralizing chimeric proteins were constructed by joining the extracellular domain of either human (Flt) or mouse (Flk) high-affinity VEGF receptors with IgG. Control chimeric proteins that did not bind VEGF were also used. VEGF-receptor chimeric proteins eliminated in vitro retinal endothelial cell growth stimulation by either VEGF (P hypoxic conditioned medium (P < 0.005) without affecting growth under nonstimulated conditions. Control proteins had no effect. To assess in vivo response, animals with bilateral retinal ischemia received intravitreal injections of VEGF antagonist in one eye and control protein in the contralateral eye. Retinal neovascularization was quantitated histologically by a masked protocol. Retinal neovascularization in the eye injected with human Flt or murine Flk chimeric protein was reduced in 100% (25/25; P < 0.0001) and 95% (21/22; P < 0.0001) of animals, respectively, compared to the control treated eye. This response was evident after only a single intravitreal injection and was dose dependent with suppression of neovascularization noted after total delivery of 200 ng of protein (P < 0.002). Reduction of histologically evident neovascular nuclei per 6-um section averaged 47% ± 4% (P < 0.001) and 37% ± 2% (P < 0.001) for Flt and Flk chimeric proteins with maximal inhibitory effects of 77% and 66

  10. Distribution of 131I-labeled recombinant human erythropoietin in maternal and fetal organs following intravenous administration in pregnant rats

    International Nuclear Information System (INIS)

    Yilmaz, O.; Lambrecht, F.Y.; Durkan, K.; Gokmen, N.; Erbayraktar, S.

    2007-01-01

    The aim of the present study was to demonstrate the possible transplacental transmission of 131 I labeled recombinant human erythropoietin ( 131 I-rh-EPO) in pregnant rats and its distribution through maternal and fetal organs. Six Wistar Albino Rats in their pregnancy of 18 days were used 131 I labeled recombinant human erythropoietin (specific activity = 2.4 μCi/IU) was injected into the tail vein of rats. After 30 minutes labeled erythropoietin infusion maternal stomach, kidney, lung, liver, brain and heart as well as fetus were removed. Then, the same organs were removed from each fetus. Measuring weight of maternal and fetal organs as well as placenta were followed by radioactivity count via Cd(Te) detector. 131 I labeled recombinant human erythropoietin was found to be able to pass rat placenta and its distribution order in fetal organs was similar to those of maternal organs. Besides, as measurements were performed closer to cornu uteri, uptakes were decreasing in every fetus and its corresponding placenta. (author)

  11. 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; Bønding, Signe Helbo

    2015-01-01

    fat oxidation were measured. Biopsies of the vastus lateralis muscle were obtained before and after the intervention. Recombinant erythropoietin treatment increased mitochondrial O2 flux during ADP stimulated state 3 respiration in the presence of complex I and II substrates (malate, glutamate...

  12. 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,

  13. Generation and phenotypic analysis of a transgenic line of rabbits secreting active recombinant human erythropoietin in the milk

    Czech Academy of Sciences Publication Activity Database

    Mikuš, Tomáš; Poplštein, M.; Sedláková, J.; Landa, Vladimír; Jeníková, Gabriela; Trefil, P.; Lidický, J.; Malý, Petr

    2004-01-01

    Roč. 13, č. 5 (2004), s. 487-498 ISSN 0962-8819 R&D Projects: GA ČR GA304/03/0090 Institutional research plan: CEZ:AV0Z5052915 Keywords : erythropoietin, mammary gland, transgenic rabbit Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.107, year: 2004

  14. Alterations of systemic and muscle iron metabolism in human subjects treated with low-dose recombinant erythropoietin

    DEFF Research Database (Denmark)

    Robach, Paul; Recalcati, Stefania; Girelli, Domenico

    2009-01-01

    healthy volunteers were treated with recombinant erythropoietin (rhEpo) for 1 month. As expected, the treatment efficiently increased erythropoiesis and stimulated bone marrow iron use. It was also associated with a prompt and considerable decrease in urinary hepcidin and a slight transient increase...

  15. Polymorphisms of VEGF and VEGF receptors are associated with the occurrence of ovarian hyperstimulation syndrome (OHSS)-a retrospective case-control study.

    Science.gov (United States)

    Nouri, Kazem; Haslinger, Peter; Szabo, Ladislaus; Sator, Michael; Schreiber, Martin; Schneeberger, Christian; Pietrowski, Detlef

    2014-01-01

    Ovarian hyperstimulation syndrome (OHSS) is the most serious complication of IVF/ICSI therapy. The pathophysiology and etiology of the disease is still not fully clarified. To assess whether polymorphisms of the VEGF/VEGF-receptor system contribute to the occurrence of ovarian hyperstimulation syndrome (OHSS), we performed a retrospective analysis of 116 OHSS patients, and 124 female controls. The following SNPs were genotyped: Rs2071559 (VEGFR2-604); rs2305948 (VEGFR2-1192); rs1870377 (VEGFR2-1719); rs2010963 (VEGF-405); and rs111458691 (VEGFR1-519). Odds ratios (ORs) were estimated with a 95% confidence interval (CI). Linkage disequilibrium (LD) analysis was performed in the three loci of the VEGFR2 gene. We found an overrepresentation of the T allele of the VEGFR1-519 polymorphism in OHSS patients (P = 0.02, OR: 3.62, CI: 1.16 - 11.27). By genotype modeling, we found that polymorphism of VEGFR1-519 and VEGF-405 showed significant differences in patients and controls (p = 0.02, OR: 3.79 CI: 1.98 - 11.97 and p = 0.000005, OR: 0.29, CI: 0.17 - 0.50). LD analysis revealed significant linkage disequilibrium in VEGFR2. Polymorphisms in the VEGFR2 gene and in the VEGF gene are associated with the occurrence of OHSS. This strengthens the evidence for an important role of the VEGF/VEGF- receptor system in the occurrence of OHSS.

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

    Science.gov (United States)

    Farajpour, Zahra; Rahbarizadeh, Fatemeh; Kazemi, Bahram; Ahmadvand, Davoud

    2014-03-28

    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. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. VEGF and bFGF Gene Polymorphisms in Patients with Non-Hodgkin's Lymphoma

    Directory of Open Access Journals (Sweden)

    Tomasz Wróbel

    2013-01-01

    Full Text Available Angiogenesis and lymphangiogenesis are important in the proliferation and survival of the malignant hematopoietic neoplasms, including non-Hodgkin’s lymphomas (NHLs. Vascular endothelial growth factor (VEGF and basic fibroblast growth factor (bFGF play an important role in the initiation of angiogenesis. Both VEGF and bFGF have been reported to have prognostic significance in NHL. The present study aimed to determine an association between the VEGF and bFGF gene polymorphisms and disease susceptibility and progression. VEGF (rs3025039; 936 C>T and bFGF (rs308395, −921 G>C variants were determined in 78 NHL patients and 122 healthy individuals by PCR-RFLP technique. The presence of the VEGF 936T allele was found to significantly associate with worse prognosis of the disease (expressed by the highest International Prognostic Index (IPI (0.41 versus 0.20, for IPI 4 among patients having and lacking the T allele. The VEGF 936T variant was also more frequent among patients with IPI 4 than in controls (OR = 3.37, . The bFGF −921G variant was more frequently detected among patients with aggressive as compared to those with indolent histological subtype (0.37 versus 0.18, and healthy individuals (0.37 versus 0.19, OR = 2.51, . These results imply that VEGF and bFGF gene polymorphisms have prognostic significance in patients with NHL.

  18. VEGF and VEGFR-2 (KDR) internalization is required for endothelial recovery during wound healing

    International Nuclear Information System (INIS)

    Constantino Rosa Santos, Susana; Miguel, Claudia; Domingues, Ines; Calado, Angelo; Zhu Zhenping; Wu Yan; Dias, Sergio

    2007-01-01

    Vascular endothelial growth factor (VEGF) receptor activation regulates endothelial cell (EC) survival, migration and proliferation. Recently, it was suggested the cross-talk between the VEGF receptors-1 (FLT-1) and -2 (KDR) modulated several of these functions, but the detailed molecular basis for such interactions remained unexplained. Here we demonstrate for the first time that VEGF stimulation of EC monolayers induced a rapid FLT-1-mediated internalization of KDR to the nucleus, via microtubules and the endocytic pathway, internalization which required the activation of PI 3-kinase/AKT. KDR deletion mutants were generated in several tyrosine residues; in these, VEGF-induced KDR internalization was impaired, demonstrating this process required activation (phosphorylation) of the receptor. Furthermore, we demonstrate that in vitro wounding of EC monolayers leads to a rapid and transient internalization of VEGF + KDR to the nucleus, which is essential for monolayer recovery. Notably, FLT-1 blockade impedes VEGF and KDR activation and internalization, blocking endothelial monolayer recovery. Our data reveal a previously unrecognized mechanism induced by VEGF on EC, which regulates EC recovery following wounding, and as such indicate novel targets for therapeutic intervention

  19. Increased expression of EMMPRIN and VEGF in the rat brain after gamma irradiation.

    Science.gov (United States)

    Wei, Ming; Li, Hong; Huang, Huiling; Xu, Desheng; Zhi, Dashi; Liu, Dong; Zhang, Yipei

    2012-03-01

    The extracellular matrix metalloproteinase inducer (EMMPRIN) has been known to play a key regulatory role in pathological angiogenesis. A elevated activation of vascular endothelial growth factor (VEGF) following radiation injury has been shown to mediate blood-brain barrier (BBB) breakdown. However, the roles of EMMPRIN and VEGF in radiation-induced brain injury after gamma knife surgery (GKS) are not clearly understood. In this study, we investigated EMMPRIN changes in a rat model of radiation injury following GKS and examined potential associations between EMMPRIN and VEGF expression. Adult male rats were subjected to cerebral radiation injury by GKS under anesthesia. We found that EMMPRIN and VEGF expression were markedly upregulated in the target area at 8-12 weeks after GKS compared with the control group by western blot, immunohistochemistry, and RT-PCR analysis. Immunofluorescent double staining demonstrated that EMMPRIN signals colocalized with caspase-3 and VEGF-positive cells. Our data also demonstrated that increased EMMPRIN expression was correlated with increased VEGF levels in a temporal manner. This is the first study to show that EMMPRIN and VEGF may play a role in radiation injuries of the central nervous system after GKS.

  20. Vibration induced hearing loss in guinea pig cochlea: expression of TNF-alpha and VEGF.

    Science.gov (United States)

    Zou, Jing; Pyykkö, Ilmari; Sutinen, Päivi; Toppila, Esko

    2005-04-01

    Transcranial vibration was applied for seven animals at a frequency of 250 Hz for 15 min, and five animals were used as normal controls to investigate cellular and molecular mechanism linked to vibration-induced hearing loss in animal model. Compound action potential (CAP) thresholds were measured by round window niche electrode. The expression of tumour necrosis factor alpha (TNF-alpha) and its receptors (TNF R1, TNF R2), vascular endothelium growth factor (VEGF) and its receptors (VEGF R1, VEGF R2) were analysed by immunohistochemistry. Transcranial vibration caused expression of TNF-alpha, TNF R1 and TNF R2 in the cochlea and the expression of TNF R2 was stronger than that of TNF R1. Vibration also induced VEGF and VEGF R2 expression in the cochlea. The average immediate hearing loss was 62 dB and after three days still 48 dB. It is concluded that transcranial vibration as during temporal bone drilling produces cochlear shear stress that is connected with up-regulation of TNF-alpha and its receptors. Also VEGF and VEGF R2 are up-regulated. These responses may be linked to both the damage and repair process of the cochlea.

  1. Expression and significance of HIF-1α and VEGF in rats with diabetic retinopathy

    Institute of Scientific and Technical Information of China (English)

    Hong-Tao Yan; Guan-Fang Su

    2014-01-01

    Objective:To investigate the expression of hypoxia inducible factor-1α(HIF-1α) and vascular endothelial growth factor(VEGF) in diabetic retinopathy(DR) rats and its effect on theDR occurrence and development.Methods:A total of120SD rats were randomly divided into trial group and control group with60 in each.STZi.p. was used in the trial group to establish theDM model, citrate buffer salt of same amount was usedi.p. to the control group.1,3 and6 months after injection, respective20 rats were sacrificed in each group to observe expression ofHIF-1α andVEGF in the rat retina tissue at different time points.Results:Expression ofHIF-1α andVEGF were negative in the control group; expression ofHIF-1α andVEGF protein in retinal tissue were weak after1 month ofDR mold formation.It showed progressive enhancement along with the progression in different organizations, differences between groups were significant (P<0.05).Conclusions:Expressions ofHIF-1α andVEGF were correlated with disease progression in early diabetic retinopathy.Retinal oxygen can induce over-expression ofHIF-1α andVEGF.It shows thatHIF-1α andVEGF play an important role in the pathogenesis ofDR.

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

    International Nuclear Information System (INIS)

    Sun, Jinqiao; Sha, Bin; Zhou, Wenhao; Yang, Yi

    2010-01-01

    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.

  3. Intravitreally Injected Anti-VEGF Antibody Reduces Brown Fat in Neonatal Mice.

    Science.gov (United States)

    Jo, Dong Hyun; Park, Sung Wook; Cho, Chang Sik; Powner, Michael B; Kim, Jin Hyoung; Fruttiger, Marcus; Kim, Jeong Hun

    2015-01-01

    Anti-vascular endothelial growth factor (VEGF) agents are the mainstay treatment for various angiogenesis-related retinal diseases. Currently, bevacizumab, a recombinant humanized anti-VEGF antibody, is trailed in retinopathy of prematurity, a vasoproliferative retinal disorder in premature infants. However, the risks of systemic complications after intravitreal injection of anti-VEGF antibody in infants are not well understood. In this study, we show that intravitreally injected anti-VEGF antibody is transported into the systemic circulation into the periphery where it reduces brown fat in neonatal C57BL/6 mice. A considerable amount of anti-VEGF antibody was detected in serum after intravitreal injection. Furthermore, in interscapular brown adipose tissue, we found lipid droplet accumulation, decreased VEGF levels, loss of vascular network, and decreased expression of mitochondria-related genes, Ppargc1a and Ucp1, all of which are characteristics of "whitening" of brown fat. With increasing age and body weight, brown fat restored its morphology and vascularity. Our results show that there is a transient, but significant impact of intravitreally administered anti-VEGF antibody on brown adipose tissue in neonatal mice. We suggest that more attention should be focused on the metabolic and developmental significance of brown adipose tissue in bevacizumab treated retinopathy of prematurity infants.

  4. Intravitreally Injected Anti-VEGF Antibody Reduces Brown Fat in Neonatal Mice.

    Directory of Open Access Journals (Sweden)

    Dong Hyun Jo

    Full Text Available Anti-vascular endothelial growth factor (VEGF agents are the mainstay treatment for various angiogenesis-related retinal diseases. Currently, bevacizumab, a recombinant humanized anti-VEGF antibody, is trailed in retinopathy of prematurity, a vasoproliferative retinal disorder in premature infants. However, the risks of systemic complications after intravitreal injection of anti-VEGF antibody in infants are not well understood. In this study, we show that intravitreally injected anti-VEGF antibody is transported into the systemic circulation into the periphery where it reduces brown fat in neonatal C57BL/6 mice. A considerable amount of anti-VEGF antibody was detected in serum after intravitreal injection. Furthermore, in interscapular brown adipose tissue, we found lipid droplet accumulation, decreased VEGF levels, loss of vascular network, and decreased expression of mitochondria-related genes, Ppargc1a and Ucp1, all of which are characteristics of "whitening" of brown fat. With increasing age and body weight, brown fat restored its morphology and vascularity. Our results show that there is a transient, but significant impact of intravitreally administered anti-VEGF antibody on brown adipose tissue in neonatal mice. We suggest that more attention should be focused on the metabolic and developmental significance of brown adipose tissue in bevacizumab treated retinopathy of prematurity infants.

  5. Signal transduction by VEGF receptors in regulation of angiogenesis and lymphangiogenesis

    International Nuclear Information System (INIS)

    Shibuya, Masabumi; Claesson-Welsh, Lena

    2006-01-01

    The VEGF/VPF (vascular endothelial growth factor/vascular permeability factor) ligands and receptors are crucial regulators of vasculogenesis, angiogenesis, lymphangiogenesis and vascular permeability in vertebrates. VEGF-A, the prototype VEGF ligand, binds and activates two tyrosine kinase receptors: VEGFR1 (Flt-1) and VEGFR2 (KDR/Flk-1). VEGFR1, which occurs in transmembrane and soluble forms, negatively regulates vasculogenesis and angiogenesis during early embryogenesis, but it also acts as a positive regulator of angiogenesis and inflammatory responses, playing a role in several human diseases such as rheumatoid arthritis and cancer. The soluble VEGFR1 is overexpressed in placenta in preeclampsia patients. VEGFR2 has critical functions in physiological and pathological angiogenesis through distinct signal transduction pathways regulating proliferation and migration of endothelial cells. VEGFR3, a receptor for the lymphatic growth factors VEGF-C and VEGF-D, but not for VEGF-A, regulates vascular and lymphatic endothelial cell function during embryogenesis. Loss-of-function variants of VEGFR3 have been identified in lymphedema. Formation of tumor lymphatics may be stimulated by tumor-produced VEGF-C, allowing increased spread of tumor metastases through the lymphatics. Mapping the signaling system of these important receptors may provide the knowledge necessary to suppress specific signaling pathways in major human diseases

  6. Primary Cilium-Regulated EG-VEGF Signaling Facilitates Trophoblast Invasion.

    Science.gov (United States)

    Wang, Chia-Yih; Tsai, Hui-Ling; Syu, Jhih-Siang; Chen, Ting-Yu; Su, Mei-Tsz

    2017-06-01

    Trophoblast invasion is an important event in embryo implantation and placental development. During these processes, endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is the key regulator mediating the crosstalk at the feto-maternal interface. The primary cilium is a cellular antenna receiving environmental signals and is crucial for proper development. However, little is known regarding the role of the primary cilium in early human pregnancy. Here, we demonstrate that EG-VEGF regulates trophoblast cell invasion via primary cilia. We found that EG-VEGF activated ERK1/2 signaling and subsequent upregulation of MMP2 and MMP9, thereby facilitating cell invasion in human trophoblast HTR-8/SVneo cells. Inhibition of ERK1/2 alleviated the expression of MMPs and trophoblast cell invasion after EG-VEGF treatment. In addition, primary cilia were observed in all the trophoblast cell lines tested and, more importantly, in human first-trimester placental tissue. The receptor of EG-VEGF, PROKR1, was detected in primary cilia. Depletion of IFT88, the intraflagellar transporter required for ciliogenesis, inhibited primary cilium growth, thereby ameliorating ERK1/2 activation, MMP upregulation, and trophoblast cell invasion promoted by EG-VEGF. These findings demonstrate a novel function of primary cilia in controlling EG-VEGF-regulated trophoblast invasion and reveal the underlying molecular mechanism. J. Cell. Physiol. 232: 1467-1477, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Recombinant human erythropoietin and blood transfusion in low-birth weight preterm infants under restrictive transfusion guidelines

    International Nuclear Information System (INIS)

    Badiee, Z.; Pourmirzaiee, Mohmmad A.; Naseri, F.; Kelishadi, R.

    2006-01-01

    To compare the number and volume of red blood cell transfusions (RBCTs) in very low birth weight infants under restrictive red blood cell transfusion guidelines with and without erythropoietin administration. In a controlled clinical trial conducted at the neonatal intensive care unit of Alzahra Hospital, Isfahan, Iran, between April 2002 to April 2004, 60 premature infants with gestational age up to 34 weeks, birth weight up to 1500 g, and postnatal age between 8 and 14 days were included. The newborns were randomized into 2 groups: Group 1 received 3 doses of 400 IU/kg erythropoietin per week for 6 weeks, and Group 2 received no treatment aside from their conventional medications. The 2 groups did not differ significantly with respect to their mean gestational age, birth weight and hematocrit at the study entry. Fewer transfusions were administered to those receiving erythropoietin (26.7% versus 50%, p=0.03), but there was no statistically significant difference between groups with respect to volume of transfusion. Compared with the placebo group, the infants receiving erythropoietin had a higher mean hematocrit (34% +/- 4.3 versus 29% +/- 5.9, p<0.001) and absolute reticulocyte count (57 +/- 19 versus 10 +/- 4.8 x 106, p<0.001) at the end of the study. We found no significant difference in the incidence of thrombocytopenia and leukopenia between the 2 groups. We conclude that when the restrictive RBCT guidelines were followed, treatment with erythropoietin can be useful in reduction of the number of RBCTs. (author)

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

    International Nuclear Information System (INIS)

    Farajpour, Zahra; Rahbarizadeh, Fatemeh; Kazemi, Bahram; Ahmadvand, Davoud

    2014-01-01

    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

  9. 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.

  10. Hypoxia induced VEGF synthesis in visceral adipose depots of obese diabetic patients.

    Science.gov (United States)

    Fusaru, Ana Marina; Pisoschi, Cătălina Gabriela; Bold, Adriana; Taisescu, C; Stănescu, R; Hîncu, Mihaela; Crăiţoiu, Stefania; Baniţă, Ileana Monica

    2012-01-01

    VEGF is one the pro-inflammatory adipokines synthesized by the "adipose secretoma" of obese subjects as a response to hypoxic conditions; but the main function of VEGF is angiogenesis, being recognized as the most important factor increasing blood capillaries in the adipose tissue by stimulating endothelial cell growth. In this paper, we propose a comparative study of the vascular response to VEGF synthesis in the subcutaneous and central-peritoneal adipose depots in lean, obese and obese diabetic patients. We used CD31 to label the endothelial cells in order to evaluate the response of the vascular network to VEGF synthesis. Our results showed an increase of VEGF protein synthesis in obese and obese-diabetic patients compared to lean subjects where the protein was absent. The positivity for VEGF in obese diabetic samples was observed in numerous structures from the adipose depots, both in the stromal vascular fraction--blood vessels and stromal cells--as well as in the cytoplasm of adipocytes. Positivity in the vascular wall was observed more frequently in areas of perivascular and intralobular fibrosis. Obese and diabetic patients showed similar incidence of CD31 immunoreactivity with lean subjects in both subcutaneous and peritoneal depots. In conclusion, human adipose depots show a different incidence of VEGF positive cells in relation with their disposal and the metabolic status. VEGF synthesis in visceral adipose tissue is inefficient being not followed by angiogenesis to counterbalance tissue hypoxia. We suggest that may be a pathogenic link between the degrees of intralobular fibrosis in adipose depots and VEGF expression.

  11. 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.

  12. Direct evidence that the VEGF-specific antibody bevacizumab has antivascular effects in human rectal cancer

    Science.gov (United States)

    Willett, Christopher G; Boucher, Yves; di Tomaso, Emmanuelle; Duda, Dan G; Munn, Lance L; Tong, Ricky T; Chung, Daniel C; Sahani, Dushyant V; Kalva, Sanjeeva P; Kozin, Sergey V; Mino, Mari; Cohen, Kenneth S; Scadden, David T; Hartford, Alan C; Fischman, Alan J; Clark, Jeffrey W; Ryan, David P; Zhu, Andrew X; Blaszkowsky, Lawrence S; Chen, Helen X; Shellito, Paul C; Lauwers, Gregory Y; Jain, Rakesh K

    2009-01-01

    The effects of vascular endothelial growth factor (VEGF) blockade on the vascular biology of human tumors are not known. Here we show here that a single infusion of the VEGF-specific antibody bevacizumab decreases tumor perfusion, vascular volume, microvascular density, interstitial fluid pressure and the number of viable, circulating endothelial and progenitor cells, and increases the fraction of vessels with pericyte coverage in rectal carcinoma patients. These data indicate that VEGF blockade has a direct and rapid antivascular effect in human tumors. PMID:14745444

  13. 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

  14. VEGFR1-mediated pericyte ablation links VEGF and PlGF to cancer-associated retinopathy

    DEFF Research Database (Denmark)

    Cao, Renhai; Xue, Yuan; Hedlund, Eva-Maria

    2010-01-01

    . Moreover, blockade of VEGFR1 but not VEGFR2 significantly restores pericyte saturation in mature retinal vessels. Our findings link VEGF and PlGF to cancer-associated retinopathy, reveal the molecular mechanisms of VEGFR1 ligand-mediated retinopathy, and define VEGFR1 as an important target......, and adenoviral vectors ablates pericytes from the mature retinal vasculature through the VEGF receptor 1 (VEGFR1)-mediated signaling pathway, leading to increased vascular leakage. In contrast, we demonstrate VEGF receptor 2 (VEGFR2) is primarily expressed in nonvascular photoreceptors and ganglion cells...

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

    Science.gov (United States)

    Reynaud, Déborah; Sergent, Frédéric; Abi Nahed, Roland; 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.

  16. Improvement in performance status after erythropoietin treatment in lung cancer patients undergoing concurrent chemoradiotherapy

    International Nuclear Information System (INIS)

    Casas, Francesc; Vinolas, Nuria; Ferrer, Ferran; Farrus, Blanca; Gimferrer, Josep Maria; Agusti, Carles; Belda, Josep; Luburich, Patricio

    2003-01-01

    Purpose: A prospective Phase II trial was carried out to evaluate the effectiveness of erythropoietin in improving or maintaining performance status as determined by the Karnofsky performance status (KPS) score and hemoglobin (Hb) levels in lung cancer patients treated with concurrent chemoradiation (CH-RT). Methods and Materials: A total of 51 patients with lung cancer (11 with small-cell, limited stage and 40 with non-small-cell disease, 17 with Stage IIIA and 23 with Stage IIIB), who underwent three different concurrent CH-RT protocols were enrolled. Baseline Hb and KPS values were recorded, as were the nadir Hb and KPS values before concurrent CH-RT. The final Hb and KPS values were recorded the last week of concurrent CH-RT. An Hb level of ≤11 g/dL before concurrent CH-RT was required before receiving erythropoietin. Prognostic factors for KPS improvement and survival were assessed by univariate and multivariate studies. Results: Of the 51 patients, 47 (92.3%) were men (mean age 63.6 years, range 40-75). The median baseline KPS score was 80, and the mean baseline Hb was 12.2 ± 1.76 g/dL (range 9-16.9). The mean nadir and final Hb value was 9.98±0.67 g/dL (range 8.6-11) and 11.33±1.59 g/dL (range 6.9-14.4), respectively. A significant increase was seen in the Hb and KPS score (p<0.05) in the final measurements. Differences were found between the final and nadir Hb in the predictive value for differences in performance status (p=0.001). On univariate study, pathologic findings (p=0.0234), weight loss (p=0.0049), baseline Hb (p=0.0057), and final Hb improvement (p=0.0237) were prognostic factors for survival. Nadir Hb (p=0.027), final Hb improvement (p=0.0069), pathologic findings (p = 0.0006), and weight loss (p=0.0001) had significant prognostic value for survival in multivariate analysis. Conclusion: In this study, erythropoietin appears to have a significant, beneficial impact on the KPS and Hb of patients undergoing concurrent CH-RT

  17. 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...... was studied in subjects (n = 8) who received long-term Epo administration, and muscle biopsies were obtained before and after. Epo treatment did not alter mean fiber area (0.84 +/- 0.2 vs. 0.72 +/- 0.3 mm(2)), capillaries per fiber (4.3 +/- 0.5 vs. 4.4 +/- 1.3), or number of proliferating endothelial cells...

  18. The glucocorticoid receptor cooperates with the erythropoietin receptor and c-Kit to enhance and sustain proliferation of erythroid progenitors in vitro

    NARCIS (Netherlands)

    von Lindern, M.; Zauner, W.; Mellitzer, G.; Steinlein, P.; Fritsch, G.; Huber, K.; Löwenberg, B.; Beug, H.

    1999-01-01

    Although erythropoietin (Epo) is essential for the production of mature red blood cells, the cooperation with other factors is required for a proper balance between progenitor proliferation and differentiation. In avian erythroid progenitors, steroid hormones cooperate with tyrosine kinase receptors

  19. 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....

  20. Recombinant erythropoietin acutely decreases renal perfusion and decouples the renin-angiotensin-aldosterone system

    DEFF Research Database (Denmark)

    Aachmann-Andersen, Niels J.; Christensen, Soren J.; Lisbjerg, Kristian

    2018-01-01

    The effect of recombinant erythropoietin (rhEPO) on renal and systemic hemodynamics was evaluated in a randomized double-blinded, cross-over study. Sixteen healthy subjects were tested with placebo, or low-dose rhEPO for 2 weeks, or high-dose rhEPO for 3 days. Subjects refrained from excessive salt...... that seems to decouple the activity of the renin-angiotensin-aldosterone system from changes in renal hemodynamics. This may serve as a negative feed-back mechanism on endogenous synthesis of EPO when circulating levels of EPO are high. These results demonstrates for the first time in humans a direct effect...... of rhEPO on renal hemodynamics and a decoupling of the renin-angiotensin-aldosterone system....

  1. 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.

  2. 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

    -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......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...

  3. 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...

  4. 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

    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......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...... 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...

  5. Synthesis and biological evaluation of 125I-erythropoietin as a potential radiopharmaceutical agent for tumours

    International Nuclear Information System (INIS)

    Clemente, Goncalo dos Santos; Duarte, Vera Lucia Serra

    2011-01-01

    Erythropoietin (EPO) is a glycoprotein hormone responsible for regulating erythropoiesis. Expression of EPO and EPO receptors (EPOr) has recently been demonstrated in some neoplastic cell lines and tumours, suggesting a potential new target for therapy. In this work, EPO was labeled with iodine-125 using the lactoperoxidase method, known to prevent damage to protein during radioiodination, and labeling conditions were optimized. In vitro stability studies have shown that 125 I-EPO is radiochemically stable for 20 days after radiolabeling. In vitro cell binding studies have demonstrated very low binding ( 125 I-EPO. In mice with induced melanoma, only a residual fixation in the tumour was evident. Further studies are warranted on other tumoral cell lines to better understand the binding process and internalization into cells. Studies on EPO labeled with carbon-11 could be valuable, since there is a greater chance of preserving the biological activity of the protein using this method. (author)

  6. Generation of a transplantable erythropoietin-producer derived from human mesenchymal stem cells.

    Science.gov (United States)

    Yokoo, Takashi; Fukui, Akira; Matsumoto, Kei; Ohashi, Toya; Sado, Yoshikazu; Suzuki, Hideaki; Kawamura, Tetsuya; Okabe, Masataka; Hosoya, Tatsuo; Kobayashi, Eiji

    2008-06-15

    Differentiation of autologous stem cells into functional transplantable tissue for organ regeneration is a promising regenerative therapeutic approach for cancer, diabetes, and many human diseases. Yet to be established, however, is differentiation into tissue capable of producing erythropoietin (EPO), which has a critical function in anemia. We report a novel EPO-producing organ-like structure (organoid) derived from human mesenchymal stem cells. Using our previously established relay culture system, a human mesenchymal stem cell-derived, human EPO-competent organoid was established in rat omentum. The organoid-derived levels of human EPO increased in response to anemia induced by rapid blood withdrawal. In addition, the presence of an organoid in rats suppressed for native (rat) EPO production enhanced recovery from anemia when compared with control animals lacking the organoid. Together these results confirmed the generation of a stem cell-derived organoid that is capable of producing EPO and sensitive to physiological regulation.

  7. Effects of erythropoietin administration on cerebral metabolism and exercise capacity in men

    DEFF Research Database (Denmark)

    Rasmussen, Peter; Foged, Eva M; Krogh-Madsen, Rikke

    2010-01-01

    administration of EPO. We recorded exercise capacity, transcranial ultrasonography-derived middle cerebral artery blood velocity, and arterial-internal jugular venous concentration differences of glucose and lactate. In addition, cognitive function, ratings of perceived exertion, ventilation and voluntary......Recombinant human erythropoietin (EPO) increases exercise capacity by stimulating erythropoiesis and subsequently enhancing oxygen delivery to the working muscles. In a large dose, EPO cross the blood brain barrier and may reduce central fatigue and improve cognition. In turn, this would augment...... exercise capacity independent of erythropoiesis. To test this hypothesis, 15 healthy young males (18-34 yo., 74 +/- 7 kg) received either 3 days of high dose (30,000 IU day(-1), N=7) double-blinded placebo controlled or 3 months of low dose (5,000 IU week(-1), N=8) counter-balanced open but controlled...

  8. Erythropoietin reduces neural and cognitive processing of fear in human models of antidepressant drug action

    DEFF Research Database (Denmark)

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

    2007-01-01

    with reduced attention to fear. Erythropoietin additionally reduced recognition of fearful facial expressions without affecting recognition of other emotional expressions. These actions occurred in the absence of changes in hematological parameters. CONCLUSIONS: The present study demonstrates that Epo directly......) versus saline on the neural processing of happy and fearful faces in 23 healthy volunteers. Facial expression recognition was assessed outside the scanner. RESULTS: One week after administration, Epo reduced neural response to fearful versus neutral faces in the occipito-parietal cortex consistent...... study aimed to explore the effects of Epo on neural and behavioral measures of emotional processing relevant for depression and the effects of conventional antidepressant medication. METHODS: In the present study, we used functional magnetic resonance imaging to explore the effects of Epo (40,000 IU...

  9. 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...... 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...... will present an atypical ABP profile. Including ret% as a stand-alone parameter improves the sensitivity two-fold....

  10. [Effects of benazepril and valsartan on erythropoietin levels in patients with essential hypertension].

    Science.gov (United States)

    Guo, Lin-lin; Li, Min; Wang, Ai-hong

    2011-10-01

    To compare effects of valsartan and benazepril on erythropoietin (EPO) levels in essential hypertensive patients with normal renal function. Sixty essential hypertensive patients were randomly divided into valsartan group (n=30, valsartan 80 mg/day) and benazepril group (n=30, benazepril 10 mg/day). Plasma EPO and hemoglobin (Hb) levels were measured at the start of and at 4 and 8 weeks during the treatments. EPO and Hb levels were all in normal range in the two groups. Valsartan decreased EPO levels from 14.179∓3.214 U/L (baseline) to 12.138∓2.926 U/L (PBenazepril treatment did not resulted in any obvious changes in EPO or Hb levels (P>0.05). Valsartan may lower EPO and Hb levels in patients with essential hypertension, while benazepril does not have such effects. The safety of valsartan in anemic hypertensive patients should be further investigated.

  11. 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 levels...... and glucose tolerance, without altering total body weight or retroperitoneal fat mass. Concomitantly, EPO partially rescued insulin-stimulated AKT activation, reduced markers of oxidative stress, and restored heat-shock protein 72 expression in soleus muscles from HFD-fed rats. Incubation of skeletal muscle...... not directly activate the phosphorylation of AKT in muscle cells. We propose that the reduced systemic inflammation or oxidative stress that we observed after treatment with EPO could contribute to the improvement of whole-body glucose metabolism....

  12. Effect of recombinant erythropoietin on inflammatory markers in patients with affective disorders

    DEFF Research Database (Denmark)

    Vinberg, Maj; Weikop, Pia; Olsen, Niels Vidiendal

    2016-01-01

    Aim: This study investigated the effect of repeated infusions of recombinant human erythropoietin (EPO) on markers of inflammation in patients with affective disorders and whether any changes in inflammatory markers were associated with improvements on verbal memory. Methods: In total, 83 patients......). In both sub-studies, patients were randomised in a double-blind, parallel-group design to receive eight weekly intravenous infusions of EPO (Eprex; 40,000 IU/ml) or saline (0.9% NaCl). Plasma concentrations of interleukin 6 (IL-6), interleukin 18 (IL-18) and high sensitive c-reactive protein (hsCRP) were...... and change in verbal memory. Conclusions: Repeated EPO infusions had no effect on IL-6 and IL-18 levels but produced a modest increase in hsCRP levels in patients with TRD. Changes over time in inflammatory markers were not correlated with changes in cognition suggesting that modulation of the inflammatory...

  13. Radioimmunoassay of erythropoietin and its potential in the diagnosis of fetal hypoxia

    International Nuclear Information System (INIS)

    Fingerova, H.

    1993-01-01

    Radioimmunoassay (RIA) for erythropoietin (EPO) in the serum and amniotic fluid was set up, based on donated rabbit antibody and a commercial tracer. EPO levels obtained by means of the RIA correlated well with the results obtained by means of ELISA or a commercial RIA kit. Retrospective evaluations of EPO levels in umbilical cord serum and amniotic fluid samples obtained during 171 vaginal or Cesarean section deliveries have shown that already in the course of spontaneous vaginal delivery a moderate increase of EPO in umbilical cord serum can be detected. The marked increase of EPO levels in both cord serum and amniotic fluid was always observed in relation to a severe fetal distress. (author) 3 figs., 3 refs

  14. Diurnal levels of immunoreactive erythropoietin in normal subjects and subjects with chronic lung disease

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M.E.; Garcia, J.F.; Cohen, R.A.; Cronkite, E.P.; Moccia, G.; Acevedo, J.

    1981-10-01

    Serum levels of immunoreactive erythropoietin (Ep) were measured in 48 normal male and female volunteers, ages 20-60 years, to establish a control value for Ep of 18.5 +/- 5.0 (mean +/- SD) mU/ml. Levels of the hormone were also measured sequentially over a 24 h period of time in an additional 17 normal volunteers with no diurnal variation. Diurnal levels of immunoreactive Ep were also measured in 30 subjects, with chronic lung disease. These patients, in contrast to normal subjects exhibited a diurnal variation in the level of immunoreactive Ep with peak levels occurring at midnight. The only variable measured which correlated with the serum immunoreactive Ep level in subjects with chronic lung disease was the level of carboxyhaemoglobin (P less than 0.02).

  15. [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.

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

    International Nuclear Information System (INIS)

    Dunst, J.; Becker, A.; Lautenschlaeger, C.; Markau, S.; Becker, H.; Fischer, K.; Haensgen, G.

    2002-01-01

    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 [de

  17. 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...... 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...

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

    African Journals Online (AJOL)

    HPV)- related cancer mandates the search for new treatment modalities. Therapeutic targeting of tumor vasculature is a promising strategy. The aim was to study angiogenesis in cervical carcinoma in terms of VEGF expression and assessment ...

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

    African Journals Online (AJOL)

    Bassma M. El Sabaa

    2012-01-13

    Jan 13, 2012 ... Eleven cases were low grade and 19 were high-grade cases. VEGF expression .... increasing microvascular permeability,26 degradation of extra- ...... soluble receptors in pre-invasive, invasive and recurrent cervical cancer.

  20. Cytoprotective effect of recombinant human erythropoietin produced in transgenic tobacco plants.

    Directory of Open Access Journals (Sweden)

    Farooqahmed S Kittur

    Full Text Available Asialo-erythropoietin, a desialylated form of human erythropoietin (EPO lacking hematopoietic activity, is receiving increased attention because of its broader protective effects in preclinical models of tissue injury. However, attempts to translate its protective effects into clinical practice is hampered by unavailability of suitable expression system and its costly and limit production from expensive mammalian cell-made EPO (rhuEPO(M by enzymatic desialylation. In the current study, we took advantage of a plant-based expression system lacking sialylating capacity but possessing an ability to synthesize complex N-glycans to produce cytoprotective recombinant human asialo-rhuEPO. Transgenic tobacco plants expressing asialo-rhuEPO were generated by stably co-expressing human EPO and β1,4-galactosyltransferase (GalT genes under the control of double CaMV 35S and glyceraldehyde-3-phosphate gene (GapC promoters, respectively. Plant-produced asialo-rhuEPO (asialo-rhuEPO(P was purified by immunoaffinity chromatography. Detailed N-glycan analysis using NSI-FTMS and MS/MS revealed that asialo-rhuEPO(P bears paucimannosidic, high mannose-type and complex N-glycans. In vitro cytoprotection assays showed that the asialo-rhuEPO(P (20 U/ml provides 2-fold better cytoprotection (44% to neuronal-like mouse neuroblastoma cells from staurosporine-induced cell death than rhuEPO(M (21%. The cytoprotective effect of the asialo-rhuEPO(P was found to be mediated by receptor-initiated phosphorylation of Janus kinase 2 (JAK2 and suppression of caspase 3 activation. Altogether, these findings demonstrate that plants are a suitable host for producing cytoprotective rhuEPO derivative. In addition, the general advantages of plant-based expression system can be exploited to address the cost and scalability issues related to its production.

  1. 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

  2. In vivo tumor angiogenesis imaging with site-specific labeled 99mTc-HYNIC-VEGF

    International Nuclear Information System (INIS)

    Blankenberg, Francis G.; Backer, Marina V.; Patel, Vimalkumar; Backer, Joseph M.; Levashova, Zoia

    2006-01-01

    We recently developed a cysteine-containing peptide tag (C-tag) that allows for site-specific modification of C-tag-containing fusion proteins with a bifunctional chelator, HYNIC (hydrazine nicotinamide)-maleimide. We then constructed and expressed C-tagged vascular endothelial growth factor (VEGF) and labeled it with HYNIC. We wished to test 99m Tc-HYNIC-C-tagged VEGF ( 99m Tc-HYNIC-VEGF) for the imaging of tumor vasculature before and after antiangiogenic (low continuous dosing, metronomic) and tumoricidal (high-dose) cyclophosphamide treatment. HYNIC-maleimide was reacted with the two thiol groups of C-tagged VEGF without any effect on biologic activity in vitro. 99m Tc-HYNIC-VEGF was prepared using tin/tricine as an exchange reagent, and injected via the tail vein (200-300 μCi, 1-2 μg protein) followed by microSPECT imaging 1 h later. Sequencing analysis of HYNIC-containing peptides obtained after digestion confirmed the site-specific labeling of the two accessible thiol groups of C-tagged VEGF. Tumor vascularity was easily visualized with 99m Tc/VEGF in Balb/c mice with 4T1 murine mammary carcinoma 10 days after implantation into the left axillary fat pad in controls (12.3±5.0 tumor/bkg, n=27) along with its decrease following treatment with high (150 mg/kg q.o.d. x 4; 1.14±0.48 tumor/bkg, n=9) or low (25 mg/kg q.d. x 7; 1.03±0.18 tumor/bkg, n=9) dose cyclophosphamide. Binding specificity was confirmed by observing a 75% decrease in tumor uptake of 99m Tc/biotin-inactivated VEGF, as compared with 99m Tc-HYNIC-VEGF. 99m Tc can be loaded onto C-tagged VEGF in a site-specific fashion without reducing its bioactivity. 99m Tc-HYNIC-VEGF can be rapidly prepared for the imaging of tumor vasculature and its response to different types of chemotherapy. (orig.)

  3. 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.

  4. 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....

  5. Up-regulation of VEGF and its receptor in refractory leukemia cells

    OpenAIRE

    Wang, Lei; Zhang, Wenjun; Ding, Yi; Xiu, Bing; Li, Ping; Dong, Yan; Zhu, Qi; Liang, Aibin

    2015-01-01

    Objective: To analyze the causative mechanisms in refractory leukemia cells. Methods: Vascular endothelial growth factor (VEGF) blood plasma concentrations in 35 de novo, 6 relapse, 20 remission leukemia patients and 10 healthy kids were determined via ELISA analyses. Transcription levels of the VEGF receptors (VEGFR) Fms-like tyrosine kinase-1 (Flt-1) and kinase-domain insert containing receptor (KDR) were determined in participants’ leucocytes with RT-PCR. Apoptosis rates as well as Cyt-C a...

  6. Minoxidil Induction of VEGF Is Mediated by Inhibition of HIF-Prolyl Hydroxylase

    Directory of Open Access Journals (Sweden)

    Soohwan Yum

    2017-12-01

    Full Text Available The topical application of minoxidil may achieve millimolar concentrations in the skin. We investigated whether millimolar minoxidil could induce vascular endothelial growth factor (VEGF, a possible effector for minoxidil-mediated hair growth, and how it occurred at the molecular level. Cell-based experiments were performed to investigate a molecular mechanism underlying the millimolar minoxidil induction of VEGF. The inhibitory effect of minoxidil on hypoxia-inducible factor (HIF prolyl hydroxylase-2 (PHD-2 was tested by an in vitro von Hippel–Lindau protein (VHL binding assay. To examine the angiogenic potential of millimolar minoxidil, a chorioallantoic membrane (CAM assay was used. In human keratinocytes and dermal papilla cells, millimolar minoxidil increased the secretion of VEGF, which was not attenuated by a specific adenosine receptor antagonist that inhibits the micromolar minoxidil induction of VEGF. Millimolar minoxidil induced hypoxia-inducible factor-1α (HIF-1α, and the induction of VEGF was dependent on HIF-1. Moreover, minoxidil applied to the dorsal area of mice increased HIF-1α and VEGF in the skin. In an in vitro VHL binding assay, minoxidil directly inhibited PHD-2, thus preventing the hydroxylation of cellular HIF-1α and VHL-dependent proteasome degradation and resulting in the stabilization of HIF-1α protein. Minoxidil inhibition of PHD-2 was reversed by ascorbate, a cofactor of PHD-2, and the minoxidil induction of cellular HIF-1α was abrogated by the cofactor. Millimolar minoxidil promoted angiogenesis in the CAM assay, an in vivo angiogenic test, and this was nullified by the specific inhibition of VEGF. Our data demonstrate that PHD may be the molecular target for millimolar minoxidil-mediated VEGF induction via HIF-1.

  7. Minoxidil Induction of VEGF Is Mediated by Inhibition of HIF-Prolyl Hydroxylase

    Science.gov (United States)

    Yum, Soohwan; Jeong, Seongkeun; Kim, Dohoon; Lee, Sunyoung; Kim, Wooseong; Yoo, Jin-Wook; Kwon, Oh Sang; Kim, Dae-Duk; Min, Do Sik; Jung, Yunjin

    2017-01-01

    The topical application of minoxidil may achieve millimolar concentrations in the skin. We investigated whether millimolar minoxidil could induce vascular endothelial growth factor (VEGF), a possible effector for minoxidil-mediated hair growth, and how it occurred at the molecular level. Cell-based experiments were performed to investigate a molecular mechanism underlying the millimolar minoxidil induction of VEGF. The inhibitory effect of minoxidil on hypoxia-inducible factor (HIF) prolyl hydroxylase-2 (PHD-2) was tested by an in vitro von Hippel–Lindau protein (VHL) binding assay. To examine the angiogenic potential of millimolar minoxidil, a chorioallantoic membrane (CAM) assay was used. In human keratinocytes and dermal papilla cells, millimolar minoxidil increased the secretion of VEGF, which was not attenuated by a specific adenosine receptor antagonist that inhibits the micromolar minoxidil induction of VEGF. Millimolar minoxidil induced hypoxia-inducible factor-1α (HIF-1α), and the induction of VEGF was dependent on HIF-1. Moreover, minoxidil applied to the dorsal area of mice increased HIF-1α and VEGF in the skin. In an in vitro VHL binding assay, minoxidil directly inhibited PHD-2, thus preventing the hydroxylation of cellular HIF-1α and VHL-dependent proteasome degradation and resulting in the stabilization of HIF-1α protein. Minoxidil inhibition of PHD-2 was reversed by ascorbate, a cofactor of PHD-2, and the minoxidil induction of cellular HIF-1α was abrogated by the cofactor. Millimolar minoxidil promoted angiogenesis in the CAM assay, an in vivo angiogenic test, and this was nullified by the specific inhibition of VEGF. Our data demonstrate that PHD may be the molecular target for millimolar minoxidil-mediated VEGF induction via HIF-1. PMID:29295567

  8. Collaborative interplay between FGF-2 and VEGF-C promotes lymphangiogenesis and metastasis

    DEFF Research Database (Denmark)

    Cao, Renhai; Ji, Hong; Feng, Ninghan

    2012-01-01

    Interplay between various lymphangiogenic factors in promoting lymphangiogenesis and lymphatic metastasis remains poorly understood. Here we show that FGF-2 and VEGF-C, two lymphangiogenic factors, collaboratively promote angiogenesis and lymphangiogenesis in the tumor microenvironment, leading...... endothelial cell tip cell formation is a prerequisite for FGF-2-stimulated lymphangiogenesis. In the tumor microenvironment, the reciprocal interplay between FGF-2 and VEGF-C collaboratively stimulated tumor growth, angiogenesis, intratumoral lymphangiogenesis, and metastasis. Thus, intervention and targeting...

  9. Myeloid-Cell-Derived VEGF Maintains Brain Glucose Uptake and Limits Cognitive Impairment in Obesity.

    Science.gov (United States)

    Jais, Alexander; Solas, Maite; Backes, Heiko; Chaurasia, Bhagirath; Kleinridders, André; Theurich, Sebastian; Mauer, Jan; Steculorum, Sophie M; Hampel, Brigitte; Goldau, Julia; Alber, Jens; Förster, Carola Y; Eming, Sabine A; Schwaninger, Markus; Ferrara, Napoleone; Karsenty, Gerard; Brüning, Jens C

    2016-05-05

    High-fat diet (HFD) feeding induces rapid reprogramming of systemic metabolism. Here, we demonstrate that HFD feeding of mice downregulates glucose transporter (GLUT)-1 expression in blood-brain barrier (BBB) vascular endothelial cells (BECs) and reduces brain glucose uptake. Upon prolonged HFD feeding, GLUT1 expression is restored, which is paralleled by increased expression of vascular endothelial growth factor (VEGF) in macrophages at the BBB. In turn, inducible reduction of GLUT1 expression specifically in BECs reduces brain glucose uptake and increases VEGF serum concentrations in lean mice. Conversely, myeloid-cell-specific deletion of VEGF in VEGF(Δmyel) mice impairs BBB-GLUT1 expression, brain glucose uptake, and memory formation in obese, but not in lean mice. Moreover, obese VEGF(Δmyel) mice exhibit exaggerated progression of cognitive decline and neuroinflammation on an Alzheimer's disease background. These experiments reveal that transient, HFD-elicited reduction of brain glucose uptake initiates a compensatory increase of VEGF production and assign obesity-associated macrophage activation a homeostatic role to restore cerebral glucose metabolism, preserve cognitive function, and limit neurodegeneration in obesity. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Interleukin-6 secreted by oral cancer- associated fibroblast accelerated VEGF expression in tumor and stroma cells.

    Science.gov (United States)

    Mirkeshavarz, M; Ganjibakhsh, M; Aminishakib, P; Farzaneh, P; Mahdavi, N; Vakhshiteh, F; Karimi, A; Gohari, N S; Kamali, F; Kharazifard, M J; Shahzadeh Fazeli, S A; Nasimian, A

    2017-10-31

    Oral cancer represents the sixth most common cancer type worldwide. Patients with oral cancer express high levels of IL-6 which is associated with very poor prognosis. Previous studies illustrated that IL-6 cytokine induces angiogenesis. It has also been reported that the presence of Cancer- Associated Fibroblasts (CAFs) is essential for angiogenesis. In this study, we examined the correlation between IL-6 and CAF and the role of this correlation on VEGF production. In this study, quantitative expression level of IL-6 and VEGF in CAF and Oral Cancer Cells (OCCs) examined through Real Time PCR and ELISA and western blot analysis. In addition, maintenance and retention of IL-6 and VEGF checked out in co-culture experiment of CAF and OCC cells. These experiments demonstrated that in oral cancer, CAF cell line secretes significantly more IL-6 than OCC. Also IL-6 is a factor that causes VEGF secretion in CAF cell line. CAF is the basic and the most essential source for producing IL-6 in patients with oral cancer. Secreted IL-6 is able to induce VEGF production in both CAF and OCCs. Correlation between CAF, IL-6 and VEGF could be considered as an approach for cancer therapy.

  11. Thymosin beta 10 Prompted the VEGF-C Expression in Lung Cancer Cell

    Directory of Open Access Journals (Sweden)

    Zixuan LI

    2014-05-01

    Full Text Available Background and objective Our previous study found that thymosin β10 overexpressed in lung cancer and positively correlated with differentiation, lymph node metastasis and stage of lung cancer. In this reasearch we aim to study the effects and mechanism of exogenous human recombinant Tβ10 on the expression of VEGF-C on non-small cell lung cancer. Methods After SPC, A549 and LK2 cells were treated with 100 ng/mL recombinant human Tβ10, the mRNA level of VEGF-C were detected by RT-PCR. The mean while the protein expression of VEGF-C, P-AKT and AKT were determined by Western blot assay. Results Exogenous recombinant human Tβ10 were significantly promote the expression levels of VEGF-C mRNA and protein while promoting the phosphorylation of AKT. Exogenous Tβ10 can promote the expression of VEGF-C mRNA and protein in lung cancer cell lines A549 and LK2 (P<0.05, and this effect can be inhibited by use AKT inhibitor LY294002 (P<0.05. Conclusion Tβ10 human recombinant proteins can promote the expression of VEGF-C by activating AKT phosphorylation in lung cancer cell lines.

  12. Endocrine gland derived-VEGF is down-regulated in human pituitary adenoma.

    Science.gov (United States)

    Raica, Marius; Coculescu, Mihail; Cimpean, Anca Maria; Ribatti, Domenico

    2010-10-01

    Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an angiogenic molecule restricted to endocrine glands and, particularly, to steroid-secreting cells. The expression of EG-VEGF and its significance in human adenohypophysis in physiological and pathological conditions is still unknown. In this study, we investigated by immunohistochemistry the expression of EG-VEGF in 2 samples of normal adenohypophysis and 43 bioptic samples of pituitary adenoma. Moreover, the expression of growth hormone (GH), prolactin (PRL), follicle-stimulating hormone (FSH), luteinizing hormone (LH), thyroid-stimulating hormone (TSH) and adrenocorticoprophic hormone (ACTH) were also estimated. The results of this study for the first time demonstrate a down-regulation of EG-VEGF expression in human pituitary adenoma as compared to normal adenohypophysis, suggesting an impaired function of the neoplastic cells in terms of hormone release in the blood stream, as a consequence of impaired tumor angiogenesis in the tumor. On the basis of our data showing a marked decrease in the expression of EG-VEGF in pituitary adenoma, with the exception of LH-secreting adenomas, we suggest that LH might be involved in the induction of EG-VEGF secretion.

  13. Radiation up-regulated the expression of VEGF in a canine oral melanoma cell line

    International Nuclear Information System (INIS)

    Flickinger, I.; Rütgen, B.C.; Gerner, W.; Tichy, A.; Saalmüller, A.; Kleiter, M.; Calice, I.

    2013-01-01

    To evaluate radiosensitivity and the effects of radiation on the expression of vascular endothelial growth factor (VEGF) and VEGF receptors in the canine oral melanoma cell line, TLM 1, cells were irradiated with doses of 0, 2, 4, 6, 8 and 10 Gray (Gy). Survival rates were then determined by a MTT assay, while vascular endothelial growth factor receptor (VEGFR)-1 and -2 expression was measured by flow cytometry and apoptotic cell death rates were investigated using an Annexin assay. Additionally, a commercially available canine VEGF ELISA kit was used to measure VEGF. Radiosensitivity was detected in TLM 1 cells, and mitotic and apoptotic cell death was found to occur in a radiation dose dependent manner. VEGF was secreted constitutively and significant up-regulation was observed in the 8 and 10 Gy irradiated cells. In addition, a minor portion of TLM 1 cells expressed vascular endothelial growth factor receptor (VEGFR)-1 intracellularly. VEGFR-2 was detected in the cytoplasm and was down-regulated following radiation with increasing dosages. In TLM 1 cells, apoptosis plays an important role in radiation induced cell death. It has also been suggested that the significantly higher VEGF production in the 8 and 10 Gy group could lead to tumour resistance. (author)

  14. 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.

  15. 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.

  16. Angiomodulin is a specific marker of vasculature and regulates VEGF-A dependent neo-angiogenesis

    Science.gov (United States)

    Hooper, Andrea T.; Shmelkov, Sergey V.; Gupta, Sunny; Milde, Till; Bambino, Kathryn; Gillen, Kelly; Goetz, Mollie; Chavala, Sai; Baljevic, Muhamed; Murphy, Andrew J.; Valenzuela, David M.; Gale, Nicholas W.; Thurston, Gavin; Yancopoulos, George D.; Vahdat, Linda; Evans, Todd; Rafii, Shahin

    2010-01-01

    Blood vessel formation is controlled by the balance between pro- and anti-angiogenic pathways. Although much is known about the factors that drive sprouting of neovessels, the factors that stabilize and pattern neovessels are undefined. The expression of angiomodulin (AGM), a VEGF-A binding protein, was increased in the vasculature of several human tumors as compared to normal tissue, raising the hypothesis that AGM may modulate VEGF-A-dependent vascular patterning. To elucidate the expression pattern of AGM, we developed an AGM knockin reporter mouse (AGMlacZ/+) wherein we demonstrate that AGM is predominantly expressed in the vasculature of developing embryos and adult organs. During physiological and pathological angiogenesis, AGM is upregulated in the angiogenic vasculature. Using the zebrafish model, we found that AGM is restricted to developing vasculature by 17-22 hpf. Blockade of AGM activity with morpholino oligomers (MO) results in prominent angiogenesis defects in vascular sprouting and remodeling. Concurrent knockdown of both AGM and VEGF-A results in synergistic angiogenesis defects. When VEGF-A is overexpressed, the compensatory induction of the VEGF-A receptor, VEGFR-2/flk-1, is blocked by the simultaneous injection of AGM MO. These results demonstrate that the vascular-specific marker AGM modulates vascular remodeling in part by temporizing the pro-angiogenic effects of VEGF-A. PMID:19542015

  17. 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

  18. Erythropoietin test

    Science.gov (United States)

    ... used to help determine the cause of anemia, polycythemia (high red blood cell count) or other bone ... Increased EPO level may be due to secondary polycythemia. This is an overproduction of red blood cells ...

  19. Treatment of Corneal Neovascularization Using Anti-VEGF Bevacizumab

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    Deli Krizova

    2014-01-01

    Full Text Available Purpose. To evaluate antiangiogenic effect of local use of bevacizumab (anti-VEGF antibody in patients with corneal neovascularization. Methods. Patients were divided into two groups. All patients suffered from some form of corneal neovascularization (NV. Patients in group A received 0.2–0.5 mL of bevacizumab solution subconjunctivally (concentration 25 mg/mL in a single dose. Group A included 28 eyes from 27. Patients in group B applied bevacizumab eye drops twice daily (concentration 2.5 mg/mL for two weeks. Group B included 38 eyes from 35 patients. We evaluated the number of corneal segments affected by NV, CDVA, and the incidence of complications and subjective complaints related to the treatment. The minimum follow-up period was six months. Results. By the 6-month follow-up, in group A the percentage reduction of the affected peripheral segments was 21.6% and of the central segments was 9.6%; in group B the percentage reduction of the central segments was 22.7% and of the central segments was 38.04%. In both groups we noticed a statistically significant reduction in the extent of NV. Conclusion. The use of bevacizumab seems to be an effective and safe method in the treatment of corneal neovascularization, either in the subconjunctival or topical application form.

  20. 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.)

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

    OpenAIRE

    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 progenitor cells (EPCs) and activation of the cytoprotective enzyme heme oxygenase-1 (HO-1). METHODS: Rats with flow-associated PAH, resembling pediatric PAH, were treated with HO-1 inducer EPO in the pre...

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

    OpenAIRE

    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 progenitor cells (EPCs) and activation of the cytoprotective enzyme heme oxygenase-1 (HO-1). Methods Rats with flow-associated PAH, resembling pediatric PAH, were treated with HO-1 inducer EPO i...

  3. A Simple Three-Step Method for Design and Affinity Testing of New Antisense Peptides: An Example of Erythropoietin

    OpenAIRE

    Štambuk, Nikola; Manojlović, Zoran; Turčić, Petra; Martinić, Roko; Konjevoda, Paško; Weitner, Tin; Wardega, Piotr; Gabričević, Mario

    2014-01-01

    Antisense peptide technology is a valuable tool for deriving new biologically active molecules and performing peptide–receptor modulation. It is based on the fact that peptides specified by the complementary (antisense) nucleotide sequences often bind to each other with a higher specificity and efficacy. We tested the validity of this concept on the example of human erythropoietin, a well-characterized and pharmacologically relevant hematopoietic growth factor. The purpose of the work was to ...

  4. Garlic accelerates red blood cell turnover and splenic erythropoietic gene expression in mice: evidence for erythropoietin-independent erythropoiesis.

    Directory of Open Access Journals (Sweden)

    Bünyamin Akgül

    2010-12-01

    Full Text Available Garlic (Allium sativum has been valued in many cultures both for its health effects and as a culinary flavor enhancer. Garlic's chemical complexity is widely thought to be the source of its many health benefits, which include, but are not limited to, anti-platelet, procirculatory, anti-inflammatory, anti-apoptotic, neuro-protective, and anti-cancer effects. While a growing body of scientific evidence strongly upholds the herb's broad and potent capacity to influence health, the common mechanisms underlying these diverse effects remain disjointed and relatively poorly understood. We adopted a phenotype-driven approach to investigate the effects of garlic in a mouse model. We examined RBC indices and morphologies, spleen histochemistry, RBC half-lives and gene expression profiles, followed up by qPCR and immunoblot validation. The RBCs of garlic-fed mice register shorter half-lives than the control. But they have normal blood chemistry and RBC indices. Their spleens manifest increased heme oxygenase 1, higher levels of iron and bilirubin, and presumably higher CO, a pleiotropic gasotransmitter. Heat shock genes and those critical for erythropoiesis are elevated in spleens but not in bone marrow. The garlic-fed mice have lower plasma erythropoietin than the controls, however. Chronic exposure to CO of mice on garlic-free diet was sufficient to cause increased RBC indices but again with a lower plasma erythropoietin level than air-treated controls. Furthermore, dietary garlic supplementation and CO treatment showed additive effects on reducing plasma erythropoietin levels in mice. Thus, garlic consumption not only causes increased energy demand from the faster RBC turnover but also increases the production of CO, which in turn stimulates splenic erythropoiesis by an erythropoietin-independent mechanism, thus completing the sequence of feedback regulation for RBC metabolism. Being a pleiotropic gasotransmitter, CO may be a second messenger for garlic

  5. The effects of erythropoietin signaling on telomerase regulation in non-erythroid malignant and non-malignant cells

    International Nuclear Information System (INIS)

    Uziel, Orit; Kanfer, Gil; Beery, Einat; Yelin, Dana; Shepshelovich, Daniel; Bakhanashvili, Mary; Nordenberg, Jardena; Lahav, Meir

    2014-01-01

    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

  6. Use of recombinant erythropoietin for the management of severe hemolytic disease of the newborn of a K0 phenotype mother.

    Science.gov (United States)

    Manoura, Antonia; Korakaki, Eftychia; Hatzidaki, Eleftheria; Saitakis, Emmanuel; Maraka, Sofia; Papamastoraki, Isabella; Matalliotakis, Emmanuel; Foundouli, Kaliopi; Giannakopoulou, Christine

    2007-01-01

    Very few people do not express any Kell antigens on their red blood cells (K0 phenotype). They can be immunized by transfusion or pregnancy and develop antibodies against Kell system antigens. These maternal antibodies can cause severe hemolytic disease of the fetus/newborn, as a result of the suppression of erythropoiesis and hemolysis. Multiple intrauterine transfusions in the management of severe hemolytic disease have been shown to cause erythropoietic suppression as well. Recombinant erythropoietin has been successfully used in the management of late anemia of infants with Rh hemolytic disease and in 1 case of KEL1 (Kell)-associated hemolytic disease. The authors present the case of severe hemolytic disease of a newborn due to KEL5 (Ku) isoimmunization of his K0 phenotype mother. Regular intrauterine transfusions were performed to manage the severe fetal anemia (Hb 3 g/dL). A male infant was born at the 36th week of gestation having normal hemoglobin (15.8 g/dL) and developed only mild hyperbilirubinemia. On the 15th day of life, the infant's hematocrit had fallen to 27.3%, with low reticulocyte count and low erythropoietin level. The infant was managed successfully with recombinant erythropoietin.

  7. A Simple Three-Step Method for Design and Affinity Testing of New Antisense Peptides: An Example of Erythropoietin

    Directory of Open Access Journals (Sweden)

    Nikola Štambuk

    2014-05-01

    Full Text Available Antisense peptide technology is a valuable tool for deriving new biologically active molecules and performing peptide–receptor modulation. It is based on the fact that peptides specified by the complementary (antisense nucleotide sequences often bind to each other with a higher specificity and efficacy. We tested the validity of this concept on the example of human erythropoietin, a well-characterized and pharmacologically relevant hematopoietic growth factor. The purpose of the work was to present and test simple and efficient three-step procedure for the design of an antisense peptide targeting receptor-binding site of human erythropoietin. Firstly, we selected the carboxyl-terminal receptor binding region of the molecule (epitope as a template for the antisense peptide modeling; Secondly, we designed an antisense peptide using mRNA transcription of the epitope sequence in the 3'→5' direction and computational screening of potential paratope structures with BLAST; Thirdly, we evaluated sense–antisense (epitope–paratope peptide binding and affinity by means of fluorescence spectroscopy and microscale thermophoresis. Both methods showed similar Kd values of 850 and 816 µM, respectively. The advantages of the methods were: fast screening with a small quantity of the sample needed, and measurements done within the range of physicochemical parameters resembling physiological conditions. Antisense peptides targeting specific erythropoietin region(s could be used for the development of new immunochemical methods. Selected antisense peptides with optimal affinity are potential lead compounds for the development of novel diagnostic substances, biopharmaceuticals and vaccines.

  8. 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.

  9. The effects of erythropoietin signaling on telomerase regulation in non-erythroid malignant and non-malignant cells

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. Transcription regulation of the vegf gene by the BMP/Smad pathway in the angioblast of zebrafish embryos

    International Nuclear Information System (INIS)

    He Chen; Chen Xiaozhuo

    2005-01-01

    Vascular endothelial growth factor (VEGF) is a mitogen that is critically involved in vasculogenesis, angiogenesis, and hematopoiesis. However, what and how transcription factors participate in the regulation of vegf gene expression are not fully understood. Here we report the cloning and sequencing of the zebrafish vegf promoter which revealed that the promoter contains a number of bone morphogenetic protein (BMP)-activated Smad binding elements (SBE), implicating Smad1 and Smad5 in the regulation of BMP-induced expression of vegf. Electrophoretic mobility shift assays of adding recombinant Smad proteins to the SBE-containing DNA oligonucleotides that represent portions of zebrafish vegf promoter resulted in mobility shift of the oligonucleotides. These changes demonstrate potential interactions between Smad1/5 and the vegf promoter. Reporter activity assays using the wild-type or SBE-deleted vegf promoters to drive the luciferase reporter gene expression revealed that Smad1 stimulated while Smad5 repressed the vegf promoter activity in zebrafish embryos. These data indicate that the BMP/Smad signaling pathway is involved in the regulation of zebrafish vegf transcription. In addition, we demonstrate that transgenic expression of human BMP4 in zebrafish embryos induced an expansion of the posterior intermediate cell mass (ICM, also commonly called blood island), a population of cells containing endothelial and hematopoietic precursors. In the expanded ICM, vegf and VEGF receptor 2 (flk-1) were ectopically co-expressed, suggesting that an autocrine/paracrine regulation of vegf expression may exist and contribute to the BMP-induced hemangiogenic cell proliferation

  15. VEGF induces proliferation of human hair follicle dermal papilla cells through VEGFR-2-mediated activation of ERK

    International Nuclear Information System (INIS)

    Li, Wei; Man, Xiao-Yong; Li, Chun-Ming; Chen, Jia-Qi; Zhou, Jiong; Cai, Sui-Qing; Lu, Zhong-Fa; Zheng, Min

    2012-01-01

    Vascular endothelial growth factor (VEGF) is one of the strongest regulators of physiological and pathological angiogenesis. VEGF receptor 2 (VEGFR-2), the primary receptor for VEGF, is thought to mediate major functional effects of VEGF. Previously, we have localized both VEGF and VEGFR-2 in human hair follicles. In this study, we further defined the expression and roles of VEGFR-2 on human hair follicle dermal papilla (DP) cells. The expression of VEGFR-2 on DP cells was examined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis separately, and localization of VEGFR-2 was defined by immunofluorescence. The effect of VEGF on DP cells was analyzed by MTT assays and specific inhibitors. Finally, the role of VEGF involved in the signaling pathways was investigated by Western blot. RT-PCR and Western blot analysis demonstrated the expression of VEGFR-2 on DP cells. Immunostaining for VEGFR-2 showed strong signal on cultured human DP cells in vitro. Exogenous VEGF 165 stimulated proliferation of DP cells in a dose-dependent manner. Furthermore, this stimulation was blocked by a VEGFR-2 neutralizing antibody (MAB3571) and an ERK inhibitor (PD98059). VEGF 165 -induced phosphorylation of ERK1/2 was abolished by MAB3571 and PD98059, while the phosphorylation of p38, JNK and AKT were not changed by VEGF 165 . Taken together, VEGFR-2 is expressed on primary human hair follicle DP cells and VEGF induces proliferation of DP cells through VEGFR-2/ERK pathway, but not p38, JNK or AKT signaling. -- Highlights: ► We examine the expression of VEGFR-2 on cultured human dermal papilla (DP) cells. ► VEGF 165 stimulated proliferation of human DP cells in a dose-dependent manner. ► This stimulation was through VEGFR-2-mediated activation of ERK.

  16. Improvement in autologous human fat transplant survival with SVF plus VEGF-PLA nano-sustained release microspheres.

    Science.gov (United States)

    Li, Liqun; Pan, Shengsheng; Ni, Binting; Lin, Yuanshao

    2014-08-01

    Early neovascularization is important for autologous fat transplant survival. SVF cells are ideal seed cells. Both vascular endothelial growth factor (VEGF) and SVF cells can promote neovascularization. However, the half-life (about 50 min) of VEGF is too short to sustain an adequate local concentration. We have investigated whether VEGF-polylactic acid (PLA) nano-sustained release microspheres plus SVF cells can improve neovascularization and survival of transplanted fat tissues. SVF cells were harvested and constructed VEGF-PLA nano-sustained release microspheres in vitro. Human fat tissues was mixed with SVF cells plus VEGF-PLA, SVF cells alone or Dulbecco's modified Eagle's medium as the control. These three mixtures were injected into random sites in 18 nude mice. Two months later, the transplants were weighed and examined histologically; and capillaries were counted to quantify neovascularization. Hematoxylin-eosin (HE) and anti-VEGF stains were applied to reveal cell infiltration. The mean wet weight of fat in the SVF plus VEGF-PLA, SVF alone, and control transplants were 0.18 ± 0.013 g, 0.16 ± 0.015 g, and 0.071 ± 0.12 g, respectively; the differences between groups were statistically significant. More vessels were present in the SVF plus VEGF-PLA transplants than in the other two types. Transplants mixed with SVF cells also had an acceptable density of capillaries. Histological analysis revealed that both the SVF plus VEGF-PLA and SVF alone transplants, but not the control transplants, were composed of adipose tissue, and had less fat necrosis and less fibrosis than control specimens. SVF plus VEGF-PLA transplants had significantly greater capillary density and VEGF expression than the other two transplant groups. Thus transplanted fat tissue survival and quality can be enhanced by the addition of VEGF-PLA nano-sustained release microspheres plus SVF cells. © 2014 International Federation for Cell Biology.

  17. Clinical significance of determination of changes of serum CA125, VEGF levels after treatment in patients with endometriosis

    International Nuclear Information System (INIS)

    Dong Yan; Zhou Dongxia

    2008-01-01

    Objective: To explore the significance of changes of serum CA125, VEGF levels after treatment in patients with endometriosis. Methods: Serum CA125 (with RIA) and VEGF (with ELISA) levels were determined in 36 patients with endometriosis both before and after treatment as well as in 30 controls. Results: Before treatment, the serum CA125, VEGF levels in the patients were significantly higher than those in the controls (P<0.01). After 3 months of treatment, the levels dropped markedly, but still remained significantly higher(P<0.05). Conclusion: Serum levels of CA125 and VEGF were closely related to the disease process in patients with ehdometriosis. (authors)

  18. 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.

  19. Clinical significance of determination of changes of serum TSGF and plasma VEGF levels after treatment in patients with endometriosis

    International Nuclear Information System (INIS)

    Shi Shaohong; Tian Xiaoping

    2006-01-01

    Objective: To investigate the changes of serum TSGF and plasma VEGF levels after treatment in patients with endometriosis. Methods: Serum TSGF levels were determined with ELISA mad plasma VEGF levels with biochemistry in 31 patients with endometriosis both before and after treatment as well as in 30 controls. Results: Before treatment the serum TSGF and plasma VEGF levels in patients were significantly higher than those in the controls (P 0.05). Conclusion: Development of endometriosis were closely related to the plasma levels of VEGF and serum TSGF levels. (authors)

  20. VEGF-A isoform-specific regulation of calcium ion flux, transcriptional activation and endothelial cell migration.

    Science.gov (United States)

    Fearnley, Gareth W; Bruns, Alexander F; Wheatcroft, Stephen B; Ponnambalam, Sreenivasan

    2015-04-24

    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. © 2015. Published by The Company of Biologists Ltd.

  1. VEGF-A isoform-specific regulation of calcium ion flux, transcriptional activation and endothelial cell migration

    Directory of Open Access Journals (Sweden)

    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.

  2. 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.

  3. Autologous blood transfusion with recombinant erythropoietin treatment in anaemic patients with rheumatoid arthritis.

    Science.gov (United States)

    Tanaka, N; Ito, K; Ishii, S; Yamazaki, I

    1999-01-01

    The aim of this study was to determine the conditions under which a sufficient preoperative amount of autologous blood could be obtained with administration of rHuEPO (recombinant human erythropoietin) in anaemic patients with rheumatoid arthritis (RA). Thirty-one patients (29 female, two male) with RA who were unable to donate any autologous blood owing to a haemoglobin level of less than 11 g/dl were recruited for this study. Their mean age at the time of operation was 59.3 years. The study protocol for preoperative autologous blood donations started 2.7 weeks before surgery. All patients received 6000 IU rHuEPO intravenously three times a week, supplemented with 40 mg intravenous saccharated ferric oxide at each rHuEPO administration. The protocol also included the provision that 200 g of blood at the first and third donations and 400 g of blood at the second donation were collected. The patients who were able or unable to donate 800 g of blood by this protocol were regarded as having a good or poor response, respectively, to rHuEPO. Patients with a poor response to rHuEPO showed greater clinical symptoms (morning stiffness, the number of swollen joints, Ritchie index) and higher laboratory inflammation parameters (ESR, CRP, platelets, IL-6, TNFalpha, IL-1beta) than patients with a good response to rHuEPO. The poor-response group showed a significant decrease in the progression of inflammation compared with the good-response group. Before treatment with rHuEPO, anaemia in the poor-response group was the same as that in the good-response group, except for impairment of UIBC (unsaturated iron-binding capacity). The poor-response group had a higher blood loss than the good-response group. In conclusion, anaemic RA patients should be considered as candidates for aggressive blood conservation interventions that depend on erythropoietin-modulated erythropoiesis. However, it is important to determine this approach under good control of inflammation.

  4. In-vivo detection of the erythropoietin receptor in tumours using positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  5. Effect of intravenous iron saccharate on the requirements ofErythropoietin in Hemodialysis patients

    International Nuclear Information System (INIS)

    Shaheen, F.A.M.; Akeel, N.; Souqiyye, M.Z.

    2002-01-01

    We attempt in this study to evaluate the effect of intravenous ironsaccharate (i.v. Sach) on the erythropoietin (EPO) requirements during theinitial phase of replacement therapy with recombinant human erythropoietin(r-HuEPO) in adult chronic hemodialysis (HD) patients. We evaluated 96 studypatients who completed 12 weeks of treatment with EPO. There were 69 (72%)males and 27 (28%) females with a mean age of 44+-10 years (range 24 to 74years). The patients were initiated on EPO at 50 units/kg body weightsubcutaneously post-dialysis two to three times weekly. Intravenous iron wasadministered to maintain the ferritin levels and transferrin saturation ratiowithin normal range. There were 36 (37.5%) patients who received i.v. Sach atdoses of 100 mg at the end of dialysis two or three times per week during thewhole study period (total dose 2400-3600 mg). Of the 96 study patients, 91(94.8%) responded to the EPO. The mean hemoglobin (Hb) at entry to the studywas 72+-84 g/L (range 52-88 g/L). There was significant increase of the meanHb to 108+-10 g/L (range 70-120 grams/L) at the end of study (P 0.2and ferritin 0.2 and ferritin >100ng/ml. There were 19 patients in group I (13 received i.v. Sach), 26 in groupII (16 received i.v. Sach) and 44 in group III (seven received i.v. Sach).There was a group of seven patients who had TSAT 100ng/ml, however, none received i.v. sach and they were not included in thestratification. There was no significant difference in the mean Hb betweenpatients who received and those who did not receive i.v. Sach in thesub-groups studied. However, there was a significant decrease in the meanweekly dose of EPO in the patients who received i.v. Sach. We conclude thatroutine use of i.v. iron supplementation in chronic HD patients receivingrecombinant EPO may be beneficial in the initial phase of treatment inattaining the target Hb with lower doses of EPO, regardless of the status ofthe iron indices. (author)

  6. 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

  7. The expression of PEDF and VEGF in the gastric wall of prehepatic portal hypertensive rats.

    Science.gov (United States)

    Pan, Wei-Dong; Liu, Yanzhang; Lin, Nan; Xu, Ruiyun

    2011-01-01

    Upper gastrointestinal bleeding of portal hypertension cases may result from gastric mucosal lesions due to portal hypertensive gastropathy. The pathological changes in the vessels of the gastric wall are very important in the pathogenesis of portal hypertensive gastropathy. However, the mechanisms of these pathological changes are not completely understood. In this study, we examined the expression levels of PEDF and VEGF in the gastric wall in rats with prehepatic portal hypertension. Eighteen healthy Wistar rats were randomly divided into groups A and B. Group A was used to establish the prehepatic portal hypertensive model and group B to evaluate a sham surgery. The VEGF and PEDF expression in the rat gastric wall were detected by immunohistochemical staining and western blotting. VEGF and PEDF were mainly expressed in the basal layer of the mucosal glands. The expression levels of VEGF and PEDF in group A were higher than that in group B at 7, 10 and 14 days after surgery. The expression levels of VEFG and PEDF in group B did not show significant changes. The results from the present study showed a significantly elevated expression of both VEGF and PEDF in the gastric walls during the development of portal hypertension. The expression of these proteins was mainly located in the basal layer of the gastric mucosa.

  8. Deleterious effects of progestagen treatment in VEGF expression in corpora lutea of pregnant ewes.

    Science.gov (United States)

    Letelier, C A; Sanchez, M A; Garcia-Fernandez, R A; Sanchez, B; Garcia-Palencia, P; Gonzalez-Bulnes, A; Flores, J M

    2011-06-01

    The aim of the current study was to determine the possible effects of progestagen oestrous synchronization on vascular endothelial growth factor (VEGF) expression during sheep luteogenesis and the peri-implantation period and the relationship with luteal function. At days 9, 11, 13, 15, 17 and 21 of pregnancy, the ovaries from 30 progestagen treated and 30 ewes cycling after cloprostenol injection were evaluated by ultrasonography and, thereafter, collected and processed for immunohistochemical evaluation of VEGF; blood samples were drawn for evaluating plasma progesterone. The progestagen-treated group showed smaller corpora lutea than cloprostenol-treated and lower progesterone secretion. The expression of VEGF in the luteal cells increased with time in the cloprostenol group, but not in the progestagen-treated group, which even showed a decrease between days 11 and 13. In progestagen-treated sheep, VEGF expression in granulosa-derived parenchymal lobule capillaries was correlated with the size of the luteal tissue, larger corpora lutea had higher expression, and tended to have a higher progesterone secretion. In conclusion, the current study indicates the existence of deleterious effects from exogenous progestagen treatments on progesterone secretion from induced corpora lutea, which correlate with alterations in the expression of VEGF in the luteal tissue and, this, presumably in the processes of neoangiogenesis and luteogenesis. © 2010 Blackwell Verlag GmbH.

  9. The tetrapeptide Arg-Leu-Tyr-Glu inhibits VEGF-induced angiogenesis

    International Nuclear Information System (INIS)

    Baek, Yi-Yong; Lee, Dong-Keon; So, Ju-Hoon; Kim, Cheol-Hee; Jeoung, Dooil; Lee, Hansoo; Choe, Jongseon; Won, Moo-Ho; Ha, Kwon-Soo; Kwon, Young-Guen; Kim, Young-Myeong

    2015-01-01

    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 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

  10. Angiogenesis in cancer of unknown primary: clinicopathological study of CD34, VEGF and TSP-1

    International Nuclear Information System (INIS)

    Karavasilis, Vasilis; Malamou-Mitsi, Vasiliki; Briasoulis, Evangelos; Tsanou, Elena; Kitsou, Evangelia; Kalofonos, Haralambos; Fountzilas, George; Fotsis, Theodore; Pavlidis, Nicholas

    2005-01-01

    Cancer of unknown primary remains a mallignancy of elusive biology and grim prognosis that lacks effective therapeutic options. We investigated angiogenesis in cancer of unknown primary to expand our knowledge on the biology of these tumors and identify potential therapeutic targets. Paraffin embedded archival material from 81 patients diagnosed with CUP was used. Tumor histology was adenocarcinoma (77%), undifferentiated carcinoma (18%) and squamous cell carcinoma (5%). The tissue expression of CD34, VEGF and TSP-1 was assessed immunohistochemically by use of specific monoclonal antibodies and was analyzed against clinicopathological data. VEGF expression was detected in all cases and was strong in 83%. Stromal expression of TSP-1 was seen in 80% of cases and was strong in 20%. The expression of both proteins was not associated with any clinical or pathological parameters. Tumor MVD was higher in tumors classified as unfavorable compared to more favorable and was positively associated with VEGF and negatively with TSP-1. Angiogenesis is very active and expression of VEGF is almost universal in cancers of unknown primary. These findings support the clinical investigation of VEGF targeted therapy in this clinical setting

  11. Determination of serum leptin and vascular endothelial growth factor (VEGF) contents in patients with breast cancer

    International Nuclear Information System (INIS)

    Huang Xudong; Jin Wentao; Pan Meizhen

    2006-01-01

    Objective: To investigate the serum expression of leptin and vascular endothelial growth factor (VEGF) in patients with breast cancer and assess its diagnostic significance. Methods: Thirty-six patients with breast cancer and thirty-one patients with benign breast disorders entered this study. Serum concentration of leptin (with RIA) and VEGF ( with ELISA) were determined in these patients before operation as well as in 56 controls. All the tested subjects were post-menopausal women. Results: The difference between the leptin levels in the controls and patients with benign breast disorders was significantly; 80 was the difference between the leptin levels in controls and patients with breast cancer. Significant difference also existed between the VEGF levels in controls and patients with cancer as well as between the levels in patients with benign breast disease and patients with cancer. Also, the serum leptin and VEGF levels in the cancerous patients with axillary metastasis were significantly higher than those in patients without metastasis. Conclusion: Serum leptin and VEGF might be taken as diagnostic tumor markers for malignanay and metastasis in patients with breast cancer. (authors)

  12. 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 littermate wild-type (WT) mice were submitted to either 1) 5 wk of exercise training, 2) lifelong (from 2 to 13 mo of age) exercise training in activity wheel, 3) a single exercise bout, or 4) 4 wk of daily subcutaneous AICAR or saline injections. In skeletal muscle of PGC-1alpha KO mice, VEGF protein...... expression was approximately 60-80% lower and the capillary-to-fiber ratio approximately 20% lower than in WT. Basal VEGF mRNA expression was similar in WT and PGC-1alpha KO mice, but acute exercise and AICAR treatment increased the VEGF mRNA content in WT mice only. Exercise training of young mice increased...

  13. Retinal reperfusion in diabetic retinopathy following treatment with anti-VEGF intravitreal injections

    Directory of Open Access Journals (Sweden)

    Levin AM

    2017-01-01

    Full Text Available Ariana M Levin, Irene Rusu, Anton Orlin, Mrinali P Gupta, Peter Coombs, Donald J D’Amico, Szilárd Kiss Department of Ophthalmology, Weill Cornell Medical College, New York, NY, USA Purpose: The aim of this study is to report peripheral reperfusion of ischemic areas of the retina on ultra-widefield fluorescein angiography (UWFA following anti-vascular endothelial growth factor (VEGF intravitreal injections in patients treated for diabetic retinopathy. Methods: This study is a retrospective review of 16 eyes of 15 patients with diabetic retinopathy, who received anti-VEGF intravitreal injections and underwent pre- and postinjection UWFA. The main outcome measured was the presence of reperfusion in postinjection UWFA images in areas of the retina that demonstrated nonperfusion in preinjection images. Images were analyzed for reperfusion qualitatively and quantitatively by two graders. Results: Twelve of 16 eyes (75% or 11 of 15 patients (73.3% demonstrated reperfusion following anti-VEGF injection. On UWFA, reperfusion was detected both within the field of 7-standard field (7SF fluorescein angiography and in the periphery outside the 7SF. Four of 16 eyes or 4 of 15 patients did not demonstrate reperfusion, one of which had extensive scarring from prior panretinal photocoagulation. Conclusion: In patients with diabetic retinopathy, treatment with anti-VEGF agents can be associated with reperfusion of areas of nonperfusion, as demonstrated by UWFA. Keywords: anti-VEGF, diabetes, diabetic retinopathy, ischemia, perfusion, reperfusion

  14. Protective or pathogenic effects of vascular endothelial growth factor (VEGF) as potential biomarker in cerebral malaria.

    Science.gov (United States)

    Canavese, Miriam; Spaccapelo, Roberta

    2014-03-01

    Cerebral malaria (CM) is the major lethal complication of Plasmodium falciparum infection. It is characterized by persistent coma along with symmetrical motor signs. Several clinical, histopathological, and laboratory studies have suggested that cytoadherence of parasitized erythrocytes, neural injury by malarial toxin, and excessive inflammatory cytokine production are possible pathogenic mechanisms. Although the detailed pathophysiology of CM remains unsolved, it is thought that the binding of parasitized erythrocytes to the cerebral endothelia of microvessels, leading to their occlusion and the consequent angiogenic dysregulation play a key role in the disease pathogenesis. Recent evidences showed that vascular endothelial growth factor (VEGF) and its receptor-related molecules are over-expressed in the brain tissues of CM patients, as well as increased levels of VEGF are detectable in biologic samples from malaria patients. Whether the modulation of VEGF is causative agent of CM mortality or a specific phenotype of patients with susceptibility to fatal CM needs further evaluation. Currently, there is no biological test available to confirm the diagnosis of CM and its complications. It is hoped that development of biomarkers to identify patients and potential risk for adverse outcomes would greatly enhance better intervention and clinical management to improve the outcomes. We review and discuss here what it is currently known in regard to the role of VEGF in CM as well as VEGF as a potential biomarker.

  15. 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.

  16. The tetrapeptide Arg-Leu-Tyr-Glu inhibits VEGF-induced angiogenesis

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. 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.

  18. Development of PLGA-coated β-TCP scaffolds containing VEGF for bone tissue engineering.

    Science.gov (United States)

    Khojasteh, Arash; Fahimipour, Farahnaz; Eslaminejad, Mohamadreza Baghaban; Jafarian, Mohammad; Jahangir, Shahrbanoo; Bastami, Farshid; Tahriri, Mohammadreza; Karkhaneh, Akbar; Tayebi, Lobat

    2016-12-01

    Bone tissue engineering is sought to apply strategies for bone defects healing without limitations and short-comings of using either bone autografts or allografts and xenografts. The aim of this study was to fabricate a thin layer poly(lactic-co-glycolic) acid (PLGA) coated beta-tricalcium phosphate (β-TCP) scaffold with sustained release of vascular endothelial growth factor (VEGF). PLGA coating increased compressive strength of the β-TCP scaffolds significantly. For in vitro evaluations, canine mesenchymal stem cells (cMSCs) and canine endothelial progenitor cells (cEPCs) were isolated and characterized. Cell proliferation and attachment were demonstrated and the rate of cells proliferation on the VEGF released scaffold was significantly more than compared to the scaffolds with no VEGF loading. A significant increase in expression of COL1 and RUNX2 was indicated in the scaffolds loaded with VEGF and MSCs compared to the other groups. Consequently, PLGA coated β-TCP scaffold with sustained and localized release of VEGF showed favourable results for bone regeneration in vitro, and this scaffold has the potential to use as a drug delivery device in the future. Copyright © 2016. Published by Elsevier B.V.

  19. 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.

  20. Prognostic Impact of Erythropoietin Expression and Erythropoietin Receptor Expression on Locoregional Control and Survival of Patients Irradiated for Stage II/III Non-Small-Cell Lung Cancer

    International Nuclear Information System (INIS)

    Rades, Dirk; Setter, Cornelia; Dahl, Olav; Schild, Steven E.; Noack, Frank

    2011-01-01

    Purpose: Prognostic factors can guide the physician in selecting the optimal treatment for an individual patient. This study investigates the prognostic value of erythropoietin (EPO) and EPO receptor (EPO-R) expression of tumor cells for locoregional control and survival in non-small-cell lung cancer (NSCLC) patients. Methods and Materials: Fourteen factors were investigated in 62 patients irradiated for stage II/III NSCLC, as follows: age, gender, Karnofsky performance score (KPS), histology, grading, TNM/American Joint Committee on Cancer (AJCC) stage, surgery, chemotherapy, pack years (average number of packages of cigarettes smoked per day multiplied by the number of years smoked), smoking during radiotherapy, hemoglobin levels during radiotherapy, EPO expression, and EPO-R expression. Additionally, patients with tumors expressing both EPO and EPO-R were compared to those expressing either EPO or EPO-R and to those expressing neither EPO nor EPO-R. Results: On univariate analysis, improved locoregional control was associated with AJCC stage II cancer (p 70 (p = 0.08), an N stage of 0 to 1 (p = 0.07), and no EPO-R expression (p = 0.10). On multivariate analysis, AJCC stage II and no EPO expression remained significant. No smoking during radiotherapy was almost significant. On univariate analysis, improved survival was associated with N stage 0 to 1 (p = 0.009), surgery (p = 0.039), hemoglobin levels of ≥12 g/d (p = 0.016), and no EPO expression (p = 0.001). On multivariate analysis, N stage 0 to 1 and no EPO expression maintained significance. Hemoglobin levels of ≥12 g/d were almost significant. On subgroup analyses, patients with tumors expressing both EPO and EPO-R had worse outcomes than those expressing either EPO or EPO-R and those expressing neither EPO nor RPO-R. Conclusions: EPO expression of tumor cells was an independent prognostic factor for locoregional control and survival in patients irradiated for NSCLC. EPO-R expression showed a trend

  1. Using anti-VEGF monoclonal antibody and magnetic nanoparticles

    International Nuclear Information System (INIS)

    Chen Jing; Wuhua; Hang Deyan; Xie Changsheng

    2004-01-01

    Objective: To study the biodistribution of 131 I-anti-vascular endothelial growth factor (VEGF) monoclonal antibody (Sc-7269)-dextran magnetic nanoparticles (DMN) in nude mice bearing human liver cancer where an external magnetic field was focused on, and to evaluate its therapeutic effects and safety. Methods: Eighteen nude mice bearing human liver cancer where an external magnetic field was focused on, were used for the bio-distribution study after intratumoral injection (n=9) or intravenous injection (n=9) of 131 I-Sc-7269-DMN. Another 25 tumor-bearing nude mice were divided into five groups, four groups of them were treated with 74 MBq/ml 131 I-Sc-7269-DMN, 131 I-Sc-7269, 131 I-DMN and 131 I by a single intratumoral injection, respectively. And an external magnetic field was bound to the tumor of the nude mice that were injected 131 I-Sc-7269-DMN or 131 I-DMN. For control study, the remaining one group was injected with physiological saline. Tumor growth delay (TGD) and tumor inhibition rate were observed as antitumor effects. Peripheral white cell counts and the loss of body weight were tested as indicators of systemic toxicity. Results: The retention percentages of radioactivity (%ID/g) in tumors after intratumoral injection were 104.06, 101.58 and 100.96%ID/g at 4, 24 and 48 h, respectively, while in the case of intravenous injection, the %ID/g values were lower (85.33, 89.67 and 90.00%ID/g, respectively, P 131 I-Sc-7269-DMN [ (13.3 ± 3.3) d] was the longest, and tumor inhibition rate (89.0%)was the highest compared with that in other groups (P 131 I-Sc-7269-DMN-treated mice as monitored by the decrease in peripheral white cell counts and the loss of body weight. Conclusions: The radioimmunotherapy with intratumoral injection of 131 I-Sc-7269-DMN may be safe and efficient for the treatment of liver cancer. Furthermore, the radioimmunotherapy using DMN as a carrier system may be a highly potential approach in targeted treatment of other kinds of tumors

  2. Clinical procedure for colon carcinoma tissue sampling directly affects the cancer marker-capacity of VEGF family members

    International Nuclear Information System (INIS)

    Pringels, Sarah; Van Damme, Nancy; De Craene, Bram; Pattyn, Piet; Ceelen, Wim; Peeters, Marc; Grooten, Johan

    2012-01-01

    mRNA levels of members of the Vascular Endothelial Growth Factor family (VEGF-A, -B, -C, -D, Placental Growth Factor/PlGF) have been investigated as tissue-based markers of colon cancer. These studies, which used specimens obtained by surgical resection or colonoscopic biopsy, yielded contradictory results. We studied the effect of the sampling method on the marker accuracy of VEGF family members. Comparative RT-qPCR analysis was performed on healthy colon and colon carcinoma samples obtained by biopsy (n = 38) or resection (n = 39) to measure mRNA expression levels of individual VEGF family members. mRNA levels of genes encoding the eicosanoid enzymes cyclooxygenase 2 (COX2) and 5-lipoxygenase (5-LOX) and of genes encoding the hypoxia markers glucose transporter 1 (GLUT-1) and carbonic anhydrase IX (CAIX) were included as markers for cellular stress and hypoxia. Expression levels of COX2, 5-LOX, GLUT-1 and CAIX revealed the occurrence in healthy colon resection samples of hypoxic cellular stress and a concurrent increment of basal expression levels of VEGF family members. This increment abolished differential expression of VEGF-B and VEGF-C in matched carcinoma resection samples and created a surgery-induced underexpression of VEGF-D. VEGF-A and PlGF showed strong overexpression in carcinoma samples regardless of the sampling method. Sampling-induced hypoxia in resection samples but not in biopsy samples affects the marker-reliability of VEGF family members. Therefore, biopsy samples provide a more accurate report on VEGF family mRNA levels. Furthermore, this limited expression analysis proposes VEGF-A and PlGF as reliable, sampling procedure insensitive mRNA-markers for molecular diagnosis of colon cancer

  3. EG-VEGF controls placental growth and survival in normal and pathological pregnancies: case of fetal growth restriction (FGR).

    Science.gov (United States)

    Brouillet, S; Murthi, P; Hoffmann, P; Salomon, A; Sergent, F; De Mazancourt, P; Dakouane-Giudicelli, M; Dieudonné, M N; Rozenberg, P; Vaiman, D; Barbaux, S; Benharouga, M; Feige, J-J; Alfaidy, N

    2013-02-01

    Identifiable causes of fetal growth restriction (FGR) account for 30 % of cases, but the remainders are idiopathic and are frequently associated with placental dysfunction. We have shown that the angiogenic factor endocrine gland-derived VEGF (EG-VEGF) and its receptors, prokineticin receptor 1 (PROKR1) and 2, (1) are abundantly expressed in human placenta, (2) are up-regulated by hypoxia, (3) control trophoblast invasion, and that EG-VEGF circulating levels are the highest during the first trimester of pregnancy, the period of important placental growth. These findings suggest that EG-VEGF/PROKR1 and 2 might be involved in normal and FGR placental development. To test this hypothesis, we used placental explants, primary trophoblast cultures, and placental and serum samples collected from FGR and age-matched control women. Our results show that (1) EG-VEGF increases trophoblast proliferation ([(3)H]-thymidine incorporation and Ki67-staining) via the homeobox-gene, HLX (2) the proliferative effect involves PROKR1 but not PROKR2, (3) EG-VEGF does not affect syncytium formation (measurement of syncytin 1 and 2 and β hCG production) (4) EG-VEGF increases the vascularization of the placental villi and insures their survival, (5) EG-VEGF, PROKR1, and PROKR2 mRNA and protein levels are significantly elevated in FGR placentas, and (6) EG-VEGF circulating levels are significantly higher in FGR patients. Altogether, our results identify EG-VEGF as a new placental growth factor acting during the first trimester of pregnancy, established its mechanism of action, and provide evidence for its deregulation in FGR. We propose that EG-VEGF/PROKR1 and 2 increases occur in FGR as a compensatory mechanism to insure proper pregnancy progress.

  4. IL-6 Promotes FSH-Induced VEGF Expression Through JAK/STAT3 Signaling Pathway in Bovine Granulosa Cells

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    Meng Yang

    2017-11-01

    Full Text Available Background/Aims: Vascular endothelial growth factor (VEGF has been demonstrated to play a pivotal role in the regulation of angiogenesis in ovarian follicular development, particularly during the preovulatory period. Although numerous studies have shown that interleukin-6 (IL-6 is one of the major inducing factors that regulate the expression of VEGF in non-ovarian cells, whether it involved in regulating the expression of VEGF in normal ovarian granulosa cells is still unknown. The aim of this study was to elucidate the mechanisms underlying the effect of IL-6 on FSH-induced VEGF expression in bovine granulosa cells derived from large follicles. Methods: VEGF mRNA expression in granulosa cells after IL-6 with/without inhibitors treatment was analyzed by RT-qPCR. Phosphorylation levels of ERK1/2 and STAT3 proteins induced by IL-6 were analyzed by western blotting. The protein levels produced by granulosa cells were detected by ELISA. Results: High concentration of IL-6 (10ng/ml can significantly up-regulate FSH-induced VEGF gene and protein expression levels in granulosa cells, and also promote the VEGF upstream regulators HIF-1α and COX2 mRNA expression. VEGF expression levels were significantly decreased after specifically blocking HIF-1α and COX2 by using inhibitors. The up-regulation effect of IL-6 on FSH-induced VEGF expression in granulosa cells mainly through activating the JAK/STAT3 signaling pathway, which can be impaired by JAK inhibitors. Conclusion: IL-6 can promote FSH-induced VEGF expression in granulosa cells, which is mainly achieved by increasing the expression of HIF-1α and COX2.This promoting effect is mediated by activating the JAK/STAT3 pathway. Moreover, there may be a synergistic relationship between FSH and IL-6 in the regulation of VEGF expression.

  5. Significant association between polymorphism of the erythropoietin gene promoter and myelodysplastic syndrome

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    O'Brien Susan

    2010-11-01

    Full Text Available Abstract Background Myelodysplastic syndrome (MDS may be induced by certain mutagenic environmental or chemotherapeutic toxins; however, the role of susceptibility genes remains unclear. The G/G genotype of the single-nucleotide polymorphism (SNP rs1617640 in the erythropoietin (EPO promoter has been shown to be associated with decreased EPO expression. We examined the association of rs1617640 genotype with MDS. Methods We genotyped the EPO rS1617640 SNP in 189 patients with MDS, 257 with acute myeloid leukemia (AML, 106 with acute lymphoblastic leukemia, 97 with chronic lymphocytic leukemia, 353 with chronic myeloid leukemia, and 95 healthy controls. Results The G/G genotype was significantly more common in MDS patients (47/187; 25.1% than in controls (6/95; 6.3% or in patients with other leukemias (101/813; 12.4% (all P P = 0.03. Time to neutrophils recovery after therapy was significantly longer in MDS patients with the G/G genotype (P = 0.02. Conclusions These findings suggest a strong association between the rs1617640 G/G genotype and MDS. Further studies are warranted to investigate the utility of screening for this marker in individuals exposed to environmental toxins or chemotherapy.

  6. HPLC-MS/MS investigation of biochemical markers for the disclosure of erythropoietin abuse in sports

    Science.gov (United States)

    Appolonova, S. A.; Dikunets, M. A.; Rodchenkov, G. M.

    2009-04-01

    The polypeptide hormone erythropoietin (EPO), which is a forbidden doping drug, was determined by high-performance liquid chromatography combined with tandem mass spectrometry (HPLC-MS/MS). The hypothesis about the influence of EPO on the asymmetric dimethylarginine (ADMA)-dimethylargininedime-thylaminohydrolase (DDAH)-NO-synthase system was verified. Changes in this system can serve as indirect biochemical markers of the presence of the forbidden EPO drug in the organism. In the test group, the concentrations of biochemical markers varied from 10 to 40 μg/ml for ADMA and symmetrical DMA (SDMA) and from 0.5 to 10 μg/ml for arginine and citrulline. A single intravenous administration of r-HuEPO (Epocrin, 2000 ME/day) for two volunteers reliably increased ADMA, SDMA, arginine, and citrulline concentrations to 40-270 μg/ml, 40-240μg/ml, 10-60 μg/ml, and 12-140 μg/ml, respectively, with respect to the reference values. The simultaneous increase in arginine, methylarginines, and citrulline contents could be an indirect marker of EPO abuse. The method is recommended for fast screening analysis.

  7. 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.

  8. BET bromodomain inhibition rescues erythropoietin differentiation of human erythroleukemia cell line UT7

    International Nuclear Information System (INIS)

    Goupille, Olivier; Penglong, Tipparat; Lefèvre, Carine; Granger, Marine; Kadri, Zahra; Fucharoen, Suthat; Maouche-Chrétien, Leila; Leboulch, Philippe; Chrétien, Stany

    2012-01-01

    Highlights: ► UT7 erythroleukemia cells are known to be refractory to differentiate. ► Brief JQ1 treatment initiates the first steps of erythroid differentiation program. ► Engaged UT7 cells then maturate in the presence of erythropoietin. ► 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.

  9. Characterization of the structure of the erythropoietin receptor by ligand blotting

    International Nuclear Information System (INIS)

    Atkins, H.L.; Broudy, V.C.; Papayannopoulou, T.

    1991-01-01

    Erythropoietin (Epo) regulates the growth and differentiation of erythroid cells by binding to a specific receptor. We characterized the native Epo receptor on erythroleukemia cell lines by ligand blotting. Solubilized cell membrane proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred onto nitrocellulose, and probed with 125I-Epo. Specificity was demonstrated by inhibition of 125I-Epo binding by unlabeled excess Epo but not other peptide growth factors and by the cellular distribution of the Epo binding protein. A single membrane protein of 61 Kd ± 4 Kd was sufficient to bind 125I Epo in both human (OCIM2, K562) and murine (GM979, Rauscher, DA-1) cell lines. This finding is consistent with the predicted size of the Epo receptor from the murine cDNA clone. However, chemical crosslinking of 125I-Epo to its receptor has identified two Epo binding proteins of 105 Kd and 85 Kd. This difference may occur because the receptor is size fractionated before Epo binding in the ligand blot, but after Epo binding in crosslinking studies. Ligand blotting demonstrates that the native Epo receptor is composed of a single 61-Kd Epo binding protein, and suggests the presence of additional proteins of 20 to 25 Kd that associate with the receptor after Epo binding

  10. Erythropoietin protects against rhabdomyolysis-induced acute kidney injury by modulating macrophage polarization

    Science.gov (United States)

    Wang, Shuo; Zhang, Chao; Li, Jiawei; Niyazi, Sidikejiang; Zheng, Long; Xu, Ming; Rong, Ruiming; Yang, Cheng; Zhu, Tongyu

    2017-01-01

    Erythropoietin (EPO) is a well-known hormone that is clinically used for the treatment of anemia. Very recently, an increasing body of evidence showed that EPO could still regulate bioactivities of macrophages. However, the details about the immunomodulatory effect of EPO on macrophages are not fully delineated, particularly in the setting of renal damages. Therefore, in the present study, we determined whether EPO could exert an impact on the dynamics of macrophages in a well-established model of rhabdomyolysis-induced acute kidney injury and explored the potential mechanisms. EPO was found to ameliorate kidney injuries by reducing macrophages recruitment and promoting phenotype switch toward M2 macrophages in vivo. It was also confirmed that EPO could directly suppress pro-inflammatory responses of M1 macrophages and promote M2 marker expression in vitro. Data indicated the possible involvement of Jak2/STAT3/STAT6 pathway in the augmentation of EPO on M2 polarization. These results improved the understanding of the immunoregulatory capacity of EPO on macrophages, which might optimize the therapeutic modalities of EPO. PMID:28383559

  11. 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.

  12. Serum immunoreactive erythropoietin in high altitude natives with and without excessive erythrocytosis.

    Science.gov (United States)

    León-Velarde, F; Monge, C C; Vidal, A; Carcagno, M; Criscuolo, M; Bozzini, C E

    1991-05-01

    We report the estimation of blood hemoglobin (Hb), arterial blood oxygen saturation (SaO2), and serum immunoreactive erythropoietin (siEPO) in a group of Peruvian workers residing in Cerro de Pasco at 4300 m showing "excessive erythrocytosis" (EE, Monge's disease, chronic mountain sickness). These estimates were compared with those of humans residing either in Cerro de Pasco and showing "normal erythrocytosis" (NE) or in Lima (sea level, SL) to determine whether Hb and SaO2 are related to siEPO in high altitude (HA) natives with NE or EE. The three parameters showed statistically significant differences between HA and SL groups--the values in SL being lower. Significant differences were also found between NE and EE groups in Hb and SaO2. There was no statistical difference in siEPo between the two groups. The results indicate, therefore, that HA residents who develop EE are not distinguishable from residents who develop NE on the basis of estimates of siEPO. As a result, siEPO and Hb do not show a dose-response relationship in HA residents, and variation in EPO does not explain the striking variation in Hb at high altitudes.

  13. Human pluripotent stem cell-derived erythropoietin-producing cells ameliorate renal anemia in mice.

    Science.gov (United States)

    Hitomi, Hirofumi; Kasahara, Tomoko; Katagiri, Naoko; Hoshina, Azusa; Mae, Shin-Ichi; Kotaka, Maki; Toyohara, Takafumi; Rahman, Asadur; Nakano, Daisuke; Niwa, Akira; Saito, Megumu K; Nakahata, Tatsutoshi; Nishiyama, Akira; Osafune, Kenji

    2017-09-27

    The production of erythropoietin (EPO) by the kidneys, a principal hormone for the hematopoietic system, is reduced in patients with chronic kidney disease (CKD), eventually resulting in severe anemia. Although recombinant human EPO treatment improves anemia in patients with CKD, returning to full red blood cell production without fluctuations does not always occur. We established a method to generate EPO-producing cells from human induced pluripotent stem cells (hiPSCs) by modifying previously reported hepatic differentiation protocols. These cells showed increased EPO expression and secretion in response to low oxygen conditions, prolyl hydroxylase domain-containing enzyme inhibitors, and insulin-like growth factor 1. The EPO protein secreted from hiPSC-derived EPO-producing (hiPSC-EPO) cells induced the erythropoietic differentiation of human umbilical cord blood progenitor cells in vitro. Furthermore, transplantation of hiPSC-EPO cells into mice with CKD induced by adenine treatment improved renal anemia. Thus, hiPSC-EPO cells may be a useful tool for clarifying the mechanisms of EPO production and may be useful as a therapeutic strategy for treating renal anemia. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  14. Antidepressant-like effects of erythropoietin: a focus on behavioural and hippocampal processes.

    Science.gov (United States)

    Osborn, Meagan; Rustom, Nazneen; Clarke, Melanie; Litteljohn, Darcy; Rudyk, Chris; Anisman, Hymie; Hayley, Shawn

    2013-01-01

    Depression is a chronic and debilitating condition with a significant degree of relapse and treatment resistance that could stem, at least in part, from disturbances of neuroplasticity. This has led to an increased focus on treatment strategies that target brain derived neurotrophic factor (BDNF), synaptic plasticity and adult neurogenesis. In the current study we aimed to assess whether erythropoietin (EPO) would have antidepressant-like effects given its already established pro-trophic actions. In particular, we assessed whether EPO would diminish the deleterious effects of a social stressor in mice. Indeed, EPO induced anxiolytic and antidepressant-like responses in a forced swim test, open field, elevated-plus maze, and a novelty test, and appeared to blunt some of the negative behavioural effects of a social stressor. Furthermore, EPO promoted adult hippocampal neurogenesis, an important feature of effective antidepressants. Finally, a separate study using the mTOR inhibitor rapamycin revealed that antagonizing this pathway prevented the impact of EPO upon forced swim performance. These data are consistent with previous findings showing that the mTOR pathway and its neurogenic and synaptogenic effects might mediate the behavioral consequences of antidepressant agents. Our findings further highlight EPO as a possible adjunct treatment for affective disorders, as well as other stressor associated disorders of impaired neuroplasticity.

  15. Cost analysis of erythropoietin versus blood transfusions for cervical cancer patients receiving chemoradiotherapy

    International Nuclear Information System (INIS)

    Kavanagh, Brian D.; Fischer, Bernard A.; Segreti, Eileen M.; Wheelock, John B.; Boardman, Cecilia; Roseff, Susan D.; Cardinale, Robert M.; Benedict, Stanley H.; Goram, Adrian L.

    2001-01-01

    Purpose: Red blood cell (RBC) transfusions or erythropoietin (EPO) can be used to evade the detrimental effects of anemia during radiotherapy, but the economic consequences of selecting either intervention are not well defined. The RBC transfusion needs during chemoradiotherapy for cervix cancer were quantified to allow comparison of RBC transfusion costs with the projected cost of EPO in this setting. Methods and Materials: For patients receiving pelvic radiotherapy, weekly cisplatin, and brachytherapy, the RBC units transfused during treatment were tallied. RBC transfusion costs per unit included the blood itself, laboratory fees, and expected value (risk multiplied by cost) of transfusion-related viral illness. EPO costs included the drug itself and supplemental RBC transfusions when hemoglobin was not adequately maintained. An EPO dosage based on reported usage in cervix cancer patients was applied. Results: Transfusions were given for hemoglobin <10 g/dL. Among 12 consecutive patients, 10 needed at least 1 U of RBC before or during treatment, most commonly after the fifth week. A total of 37 U was given during treatment, for an average of 3.1 U/patient. The sum total of the projected average transfusion-related costs was $990, compared with the total projected EPO-related costs of $3869. Conclusions: Because no proven clinical advantage has been documented for EPO compared with RBC transfusions to maintain hemoglobin during cervix cancer treatment, for most patients, transfusions are an appropriate and appealingly less expensive option

  16. An integrative 'omics' solution to the detection of recombinant human erythropoietin and blood doping.

    Science.gov (United States)

    Pitsiladis, Yannis P; Durussel, Jérôme; Rabin, Olivier

    2014-05-01

    Administration of recombinant human erythropoietin (rHumanEPO) improves sporting performance and hence is frequently subject to abuse by athletes, although rHumanEPO is prohibited by the WADA. Approaches to detect rHumanEPO doping have improved significantly in recent years but remain imperfect. A new transcriptomic-based longitudinal screening approach is being developed that has the potential to improve the analytical performance of current detection methods. In particular, studies are being funded by WADA to identify a 'molecular signature' of rHumanEPO doping and preliminary results are promising. In the first systematic study to be conducted, the expression of hundreds of genes were found to be altered by rHumanEPO with numerous gene transcripts being differentially expressed after the first injection and further transcripts profoundly upregulated during and subsequently downregulated up to 4 weeks postadministration of the drug; with the same transcriptomic pattern observed in all participants. The identification of a blood 'molecular signature' of rHumanEPO administration is the strongest evidence to date that gene biomarkers have the potential to substantially improve the analytical performance of current antidoping methods such as the Athlete Biological Passport for rHumanEPO detection. Given the early promise of transcriptomics, research using an 'omics'-based approach involving genomics, transcriptomics, proteomics and metabolomics should be intensified in order to achieve improved detection of rHumanEPO and other doping substances and methods difficult to detect such a recombinant human growth hormone and blood transfusions.

  17. Influence of Erythropoietin Dose and Albumin Level on the Plasma Brain Natriuretic Peptide in Hemodialysis Patients

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    Alsuwaida Abdulkareem

    2006-01-01

    Full Text Available Brain natriuretic peptide (BNP levels increase in patients with congestive heart failure. Theoretically, BNP levels can be helpful in the determination of the "dry weight" of hemodialysis patients. To evaluate the effect of hemodialysis on the plasma concentration of BNP and to determine the factors that affect BNP levels during hemodialysis in patients with chronic renal failure, we studied five stable patients with chronic renal failure. A total of 15 blood samples were obtained for BNP levels at 24, 48 and 72 hours after the last hemodialysis session. The plasma BNP levels did not change significantly either with ultrafiltration volume or with time since last dialysis. However, the BNP levels correlated positively with the erythropoietin (EPO dose (r=0.98, P< 0.001 and negatively with the serum albumin levels (r = 0.94, P=0.02. Univariate analysis showed that the EPO dose (P=0.001 and the albumin level (P=0.02 were significant predictors of BNP level. Adjusted multivariate analysis showed significant interaction between the EPO dose and the albumin level (P=0.01, P=0.03 respectively. In conclusion: the plasma BNP levels were not significantly influenced by ultrafiltration volume or time since last dialysis. However, the BNP levels may be a useful prognostic parameter for assessing the risk of cardiovascular morbidity and mortality in hemodialysis patients.

  18. General anesthetics inhibit erythropoietin induction under hypoxic conditions in the mouse brain.

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    Tomoharu Tanaka

    Full Text Available Erythropoietin (EPO, originally identified as a hematopoietic growth factor produced in the kidney and fetal liver, is also endogenously expressed in the central nervous system (CNS. EPO in the CNS, mainly produced in astrocytes, is induced under hypoxic conditions in a hypoxia-inducible factor (HIF-dependent manner and plays a dominant role in neuroprotection and neurogenesis. We investigated the effect of general anesthetics on EPO expression in the mouse brain and primary cultured astrocytes.BALB/c mice were exposed to 10% oxygen with isoflurane at various concentrations (0.10-1.0%. Expression of EPO mRNA in the brain was studied, and the effects of sevoflurane, halothane, nitrous oxide, pentobarbital, ketamine, and propofol were investigated. In addition, expression of HIF-2α protein was studied by immunoblotting. Hypoxia-induced EPO mRNA expression in the brain was significantly suppressed by isoflurane in a concentration-dependent manner. A similar effect was confirmed for all other general anesthetics. Hypoxia-inducible expression of HIF-2α protein was also significantly suppressed with isoflurane. In the experiments using primary cultured astrocytes, isoflurane, pentobarbital, and ketamine suppressed hypoxia-inducible expression of HIF-2α protein and EPO mRNA.Taken together, our results indicate that general anesthetics suppress activation of HIF-2 and inhibit hypoxia-induced EPO upregulation in the mouse brain through a direct effect on astrocytes.

  19. In vitro expression of erythropoietin by transfected human mesenchymal stromal cells.

    Science.gov (United States)

    Mok, P-L; Cheong, S-K; Leong, C-F; Othman, A

    2008-01-01

    Mesenchymal stromal cells (MSC) are pluripotent progenitor cells that can be found in human bone marrow (BM). These cells have low immunogenicity and could suppress alloreactive T-cell responses. In the current study, MSC were tested for their capacity to carry and deliver the erythropoietin (EPO) gene in vitro. Expanded BM MSC was transfected with EPO-encoded plasmid pMCV1.2 and EPO-encoded MIDGE (minimalistic immunologically defined gene expression) vector by electroporation. The expressed EPO was used to induce hematopoietic stem cells (HSC) into erythroid colonies. The results showed that the MIDGE vector was more effective and stable than the plasmid (pMCV1.2) in delivering EPO gene into MSC. The supernatants containing EPO obtained from the transfected cell culture were able to induce the differentiation of HSC into erythroid colonies. MSC hold promise as a cell factory for the production of biologic molecules, and MIDGE vector is more effective and stable than the plasmid in nucleofection involving the EPO gene.

  20. THE ROLE OF ERYTHROPOIETIN IN TREATMENT OF ANEMIA IN CANCER PATIENTS

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    P. G. Berezin

    2017-01-01

    Full Text Available Malignant neoplasms are a serious pathological condition, both in terms of the course of the disease and the need for treatment, and a prognosis for the life of patients. The deterioration in the quality of life, social disadaptation (reduced physical activity, job change, fatigue, etc. is a complication of the course of the disease caused by the development of anemia, which requires a vital need for its correction. This article analyzes the efficacy of recombinant erythropoietin — Epoetin-theta in the treatment of patients with NON — myeloid tumors and CRF (chronic renal failure in cancer patients. The high efficacy and safety of drug therapy in this category of patients are demonstrated. Recommendations are given on the optimal dose of the drug in order to obtain the most pronounced clinical effect of treatment, increasing the therapeutic dose of the drug with an insufficient increase in the hemoglobin level by 100% or more allows an individual approach to the correction of anemia. The possibility of its application in routine clinical practice of the oncologist’s doctor, namely in out-patientpolyclinic conditions, has been determined.

  1. Increased red cell 2,3-diphosphoglycerate levels in haemodialysis patients treated with erythropoietin.

    Science.gov (United States)

    Horina, J H; Schwaberger, G; Brussee, H; Sauseng-Fellegger, G; Holzer, H; Krejs, G J

    1993-01-01

    The efficacy of recombinant human erythropoietin (rHuEpo) for the treatment of renal anaemia is well established. To assess the effect of rHuEpo treatment on physical performance we evaluated physical working capacity, oxygen uptake and red cell 2,3-diphosphoglycerate (DPG) values at rest and during and after exercise on a bicycle spiroergometer in eight chronically haemodialysed patients. Follow-up examination was carried out after a mean of 14 weeks (range 9-19 weeks), when mean haemoglobin had increased from 7.8 to a stable value of 13.0 g/dl in response to rHuEpo treatment (P level without rHuEpo treatment than after correction of anaemia. Therefore rHuEpo treatment results both in better oxygen transport capacity and reduced intraerythrocytic oxygen affinity, which is followed by improved oxygen delivery to tissues per unit of haemoglobin. These effects may explain the improvement of exercise capacity observed in dialysis patients after rHuEpo treatment.

  2. Blood rheology and 2,3-diphosphoglycerate levels after erythropoietin treatment.

    Science.gov (United States)

    Crowley, J P; Chazan, J A; Metzger, J B; Pono, L; Valeri, C R

    1993-01-01

    Twenty-seven transfusion dependent patients with end-stage renal disease on long-term dialysis had blood cell counts, serum chemistries, blood pressure, and whole blood viscosity measured, as well as having transfusion requirements assessed. Three months after the institution of recombinant human erythropoietin (rHU-EPO) (75 u per kg per wk), there was an 88 percent fall in transfusion requirement. After four months, the hematocrit increased from 24 +/- 3.8 to 25.6 +/- 4.2 percent, mean corpuscular volume from 93 +/- 4.9 to 97 +/- 6.6 fl, 2-3-diphosphoglycerate (2,3-DPG) from 13.2 +/- 3.2 to 15.6 +/- 4.3 microM per g of Hb. Whole blood viscosity fell from 14.1 +/- 2.1 to 12.7 +/- 2.3 seconds, and ferritin levels fell from 3282 +/- 3889 to 2131 +/- 2441 ng per ml. In eight patients in whom the dose of rHU-EPO was further increased by up to 50 units per kg three times weekly for three months, the hematocrit rose further to 29.3 +/- 3.0 percent and the rise in hematocrit was accompanied by a further increase in 2,3-DPG to 17.9 +/- 2.8 microM per g of Hb (p < 0.03). There were no major side effects or vascular complications.

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

    Science.gov (United States)

    Halim, Liem Andhyk; Brinks, Vera; Jiskoot, Wim; Romeijn, Stefan; Praditpornsilpa, Kearkiat; Assawamakin, Anunchai; Schellekens, Huub

    2014-05-01

    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 rhEPO copy products being used in Thailand. Twelve rhEPO copy products were purchased from pharmacies in Thailand, shipped under controlled cold chain conditions to the Netherlands and characterized using (1) high performance size-exclusion chromatography, (2) asymmetrical flow field-flow fractionation, (3) sodium dodecyl sulfate polyacrylamide gel electrophoresis in combination with (4) Western blotting and additionally tested for (5) host cell protein impurities as well as (6) endotoxin contamination. Some of the tested rhEPO copy products showed high aggregate levels and contained a substantial amount of protein fragments. Also, one of rhEPO copy products had a high endotoxin level, exceeding the FDA limit. Our observations show that some of the tested copy products on the Thai market differ significantly from the originator rhEPO product, Epogen®. This comparison study supports a link between the quality attributes of copy rhEPO products and their immunogenicity.

  4. BET bromodomain inhibition rescues erythropoietin differentiation of human erythroleukemia cell line UT7

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Long-term erythropoietin gene expression from transduced cells in bioisolator devices.

    Science.gov (United States)

    Yanay, Ofer; Barry, Simon C; Flint, Lisa Y; Brzezinski, Margaret; Barton, Randall W; Osborne, William R A

    2003-11-20

    Recombinant erythropoietin (EPO) is widely administered for long-term treatment of anemia associated with renal failure and other chronic diseases. The ability to deliver EPO by gene therapy would have clinical and economic benefit. We compared autologous and allogeneic transduced primary vascular smooth muscle cells for their ability to provide sustained EPO gene expression when encapsulated in TheraCyte devices implanted subcutaneously (SQ) or intraperitoneally (IP) in rats. Cells were transduced with retrovirus vector LrEpSN encoding rat EPO cDNA. Rats that received either autologous or allogeneic transduced cells showed elevated hematocrits (HCTs) ranging from 50 to 79% that were sustained for more than 12 months. The HCT of control rats remained at baseline (45.8%). Rats that received second SQ implants of either autologous or allogeneic cells showed elevations in hematocrit that were sustained for up to 12 months, suggesting the absence of immunological responses to transduced cells or implant material. All experimental groups had statistically significant elevated HCT (p TheraCyte devices was well tolerated and histological evaluation of the devices up to 12 months after surgery revealed a high degree of vascularization and no evidence of host immune response. TheraCyte devices offer a simple and safe gene delivery system that provides sustained therapeutic gene expression, permit removal and implantation of new devices, and do not require immunosuppression of the host.

  6. 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.

  7. 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.

  8. Targeting higher ferritin concentrations with intravenous iron dextran lowers erythropoietin requirement in hemodialysis patients.

    Science.gov (United States)

    DeVita, M V; Frumkin, D; Mittal, S; Kamran, A; Fishbane, S; Michelis, M F

    2003-11-01

    Although clinical use of recombinant human erythropoietin (rHuEPO) since 1989 has improved anemia in most end-stage renal disease patients, there are still many hemodialysis patients unable to maintain an adequate hematocrit (HCT) without large doses of rHuEPO. This suggests that anemia is not solely a consequence of rHuEPO deficiency, but may be due to other factors including functional iron deficiency. Since the optimal prescription for iron replacement is not yet known, we evaluated the effect of intravenous iron dextran (IVFe) infusion on serum ferritin (SFer) concentration and rHuEPO dose. Our objective was to raise and maintain serum ferritin concentrations to 2 different levels above the National Kidney Foundation Dialysis Outcome Quality Initiative standard of 100 ng/ml to determine whether, and by what degree rHuEPO dose could be lowered. HD patients on i.v. rHuEPO with a SFer concentration > or = 70 ng/ml and an HCT of requirements.

  9. Protective Effects of Erythropoietin and N-Acetylcysteine on Methotrexate-Induced Lung Injury in Rats

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    Hasan Kahraman

    2013-03-01

    Full Text Available Objective: Methotrexate (MTX is known to have deleterious side effects on lung tissue. We aimed to investigate the effects of erythropoietin (EPO and N-acetyl-cysteine (NAC on MTX-induced lung injury in rats. Study Design: Animal experiment. Material and Methods: Twenty-six female Sprague-Dawley rats were divided into 4 groups. Sham group, 0.3 mL saline; MTX group, 5 mg/kg MTX; EPO group, 5mg/kg MTX and 2000 IU/kg EPO; NAC group, 5 mg/kg MTX and 200 mg/kg NAC were administered once daily for 4 consecutive days. Malondialdehyde (MDA, superoxide dismutase (SOD, catalase (CAT and inflammation and congestion scores in lung tissues were evaluated. Results: In MTX group MDA were significantly higher, CAT and SOD were significantly lower than in sham, EPO and NAC groups (p0.005. In group MTX both scores were significantly higher than in sham (p<0.005. The congestion score of group MTX was significantly higher than those of group EPO and NAC (p<0.005. Conclusion: EPO and NAC have significant preventive effects on MTX-induced lung injury in rats. Decreased antioxidant capacity and increased MDA level may cause the oxidative damage in MTX group. Also, higher antioxidant capacity and lower MDA level may be a response to oxidative stress in EPO and NAC groups.

  10. Erythropoietin-derived nonerythropoietic peptide ameliorates experimental autoimmune neuritis by inflammation suppression and tissue protection.

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    Yuqi Liu

    Full Text Available Experimental autoimmune neuritis (EAN is an autoantigen-specific T-cell-mediated disease model for human demyelinating inflammatory disease of the peripheral nervous system. Erythropoietin (EPO has been known to promote EAN recovery but its haematopoiesis stimulating effects may limit its clinic application. Here we investigated the effects and potential mechanisms of an EPO-derived nonerythropoietic peptide, ARA 290, in EAN. Exogenous ARA 290 intervention greatly improved EAN recovery, improved nerve regeneration and remyelination, and suppressed nerve inflammation. Furthermore, haematopoiesis was not induced by ARA 290 during EAN treatment. ARA 290 intervention suppressed lymphocyte proliferation and altered helper T cell differentiation by inducing increase of Foxp3+/CD4+ regulatory T cells and IL-4+/CD4+ Th2 cells and decrease of IFN-γ+/CD4+ Th1 cells in EAN. In addition, ARA 290 inhibited inflammatory macrophage activation and promoted its phagocytic activity. In vitro, ARA 290 was shown to promote Schwann cell proliferation and inhibit its inflammatory activation. In summary, our data demonstrated that ARA 290 could effectively suppress EAN by attenuating inflammation and exerting direct cell protection, indicating that ARA 290 could be a potent candidate for treatment of autoimmune neuropathies.

  11. Fibronectin potentiates topical erythropoietin-induced wound repair in diabetic mice.

    Science.gov (United States)

    Hamed, Saher; Ullmann, Yehuda; Egozi, Dana; Daod, Essam; Hellou, Elias; Ashkar, Manal; Gilhar, Amos; Teot, Luc

    2011-06-01

    Diabetes mellitus disrupts all phases of the wound repair cascade and leads to development of chronic wounds. We previously showed that topical erythropoietin (EPO) can promote wound repair in diabetic rats. Fibronectin (FN) has a critical role throughout the process of wound healing, yet it is deficient in wound tissues of diabetic patients. Therefore, we investigated the effect of topical treatment of both EPO and FN (EPO/FN) on wound repair in diabetic mice. Full-thickness excisional skin wounds in diabetic and nondiabetic mice were treated with a cream containing vehicle, EPO, FN, or EPO/FN. We assessed the rate of wound closure, angiogenesis, apoptosis, and expression of inflammatory cytokines, endothelial nitric oxide synthase (eNOS) and β1-integrin, in the wound tissues. We also investigated the effect of EPO, FN, and EPO/FN on human dermal microvascular endothelial cells and fibroblasts cultured on fibrin-coated plates, or in high glucose concentrations. EPO/FN treatment significantly increased the rate of wound closure and this effect was associated with increased angiogenesis, increased eNOS and β1-integrin expression, and reduced expression of inflammatory cytokines and apoptosis. Our findings show that EPO and FN have an additive effect on wound repair in diabetic mice.

  12. ERYTHROPOIETIN TREATMENT FOR ANEMIA IN CHILDREN WITH CANCER – SINGLE CENTRE EXPERIENCES

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    Polona Mali

    2004-12-01

    Full Text Available Background. Anemia, a common complication during treatment of malignant disease in children, was frequently treated with red blood cell transfusions. Several studies have shown, that the introduction of recombinant human erythropoietin (rh EPO for treating anemia in patients has been effective in reducing the need for transfusions. Variable doses of EPO from 150 to 900 IU/kg body weight have been used usually three times weekly. Recently some studies showed equally effective once weekly administration of EPO with proposed doses for children of 450 to 600 IU/ kg body weight.Efficacy and safety of once weekly EPO therapy was tested in 8/10 children treated in our Unit for solid tumors and nonHodgkin’s lymphoma. In this article we would like to present our one year experience with EPO treatment.Patients and methods. Patients have subcutaneously received the EPO dose of 600 UI/ kg body weight once weekly. Hemoglobin response and transfusion needs before and during treatment with EPO were analyzed.Results. Response was seen in 7/8 of patient, with increased hemoglobin level and lower transfusion needs. Only one patient was poor responder at first, but responded perfect after twice weekly EPO application. No adverse reaction related to EPO therapy was observed.Conclusions. Our experience with treating anemia in pediatric cancer patients who undergo intensive and aggressive chemotherapy treatment regimens are good and promising. Once weekly dosage regimen is child friendly and acceptable way of treating anemia.

  13. 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 composition by hemodilution preceded an additional incremental test. Group averages were calculated for an exercise intensity ∼80% of pre-rHuEPO peak power output. After rHuEPO treatment, leg lactate release to the plasma compartment was similar to before (4.3 ± 1.6 vs 3.9 ± 2.5 mmol/min) and remained similar...... after hemodilution. Venous lactate concentration was higher (P release to the plasma compartment after rHuEPO was similar to before (19.6 ± 5.4 vs 17.6 ± 6.0 mmol/min) and remained similar after hemodilution. Nevertheless, venous p...

  14. A novel biological function of soluble biglycan: Induction of erythropoietin production and polycythemia.

    Science.gov (United States)

    Frey, Helena; Moreth, Kristin; Hsieh, Louise Tzung-Harn; Zeng-Brouwers, Jinyang; Rathkolb, Birgit; Fuchs, Helmut; Gailus-Durner, Valérie; Iozzo, Renato V; de Angelis, Martin Hrabě; Schaefer, Liliana

    2017-06-01

    Secondary polycythemia, a disease characterized by a selective increase in circulating mature erythrocytes, is caused by enhanced erythropoietin (Epo) concentrations triggered by hypoxia-inducible factor-2α (HIF-2α). While mechanisms of hypoxia-dependent stabilization of HIF-2α protein are well established, data regarding oxygen-independent regulation of HIF-2α are sparse. In this study, we generated a novel transgenic mouse model, in which biglycan was constitutively overexpressed and secreted by hepatocytes (BGN Tg ), thereby providing a constant source of biglycan released into the blood stream. We discovered that although the mice were apparently normal, they harbored an increase in mature circulating erythrocytes. In addition to erythrocytosis, the BGN Tg mice showed elevated hemoglobin concentrations, hematocrit values and enhanced total iron binding capacity, revealing a clinical picture of polycythemia. In BGN Tg mice markedly enhanced Epo mRNA expression was observed in the liver and kidney, while elevated Epo protein levels were found in liver, kidney and blood. Mechanistically, we showed that the transgenic animals had an abundance of HIF-2α protein in the liver and kidney. Finally, by transiently overexpressing circulating biglycan in mice deficient in various Toll-like receptors (TLRs), we determined that this novel function of biglycan to promote Epo synthesis was specifically mediated by a selective interaction with TLR2. Thus, we discovered a novel biological pathway of soluble biglycan inducing HIF-2α protein stabilization and Epo production presumably in an oxygen-independent manner, ultimately giving rise to secondary polycythemia.

  15. Inhibition of erythropoietin siRNA on corneal neovascularization of rabbit

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    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.

  16. 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.

  17. Comparison of the Protective Effects of Erythropoietin and Melatonin on Renal Ischemia-Reperfusion Injury.

    Science.gov (United States)

    Banaei, Shokofeh; Ahmadiasl, Nasser; Alihemmati, Alireza

    2016-07-01

    Renal ischemia-reperfusion (IR) contributes to the development of acute renal failure (ARF). Oxygen free radicals are considered to be the principal components involved in the pathophysiological tissue alterations observed during renal IR. In this study, we compared the effects of melatonin (MEL) and erythropoietin (EPO), both known antioxidant and anti-inflammatory agents, on IR-induced renal injury in rats. Wistar albino rats were unilaterally nephrectomized and then subjected to 45 minutes of renal pedicle occlusion followed by 24 hours of reperfusion. MEL (10 mg/kg, i.p) and EPO (5000 U/kg, i.p) were administered prior to the onset of ischemia. After 24 hours of reperfusion and following decapitation, blood samples were collected for the determination of the hemoglobin (Hb) and hematocrit (Hct) levels. Additionally, renal samples were taken for histological evaluation. Ischemia-reperfusion significantly decreased the observed Hb and Hct values. The histopathological findings in the IR group confirmed that there was an increase in the hyaline cast and thickening of the Bowman capsule basement membrane. Treatment with EPO or MEL significantly increased the Hb and Hct values. In the MEL + IR group, the histopathological changes were lower than those found in the EPO + IR group. Treatment with EPO and MEL had a beneficial effect on renal IR injury. The results may also indicate that MEL protects against morphological damage better than EPO in renal IR injury.

  18. Acute Vhl gene inactivation induces cardiac HIF-dependent erythropoietin gene expression.

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    Marta Miró-Murillo

    Full Text Available Von Hippel Lindau (Vhl gene inactivation results in embryonic lethality. The consequences of its inactivation in adult mice, and of the ensuing activation of the hypoxia-inducible factors (HIFs, have been explored mainly in a tissue-specific manner. This mid-gestation lethality can be also circumvented by using a floxed Vhl allele in combination with an ubiquitous tamoxifen-inducible recombinase Cre-ER(T2. Here, we characterize a widespread reduction in Vhl gene expression in Vhl(floxed-UBC-Cre-ER(T2 adult mice after dietary tamoxifen administration, a convenient route of administration that has yet to be fully characterized for global gene inactivation. Vhl gene inactivation rapidly resulted in a marked splenomegaly and skin erythema, accompanied by renal and hepatic induction of the erythropoietin (Epo gene, indicative of the in vivo activation of the oxygen sensing HIF pathway. We show that acute Vhl gene inactivation also induced Epo gene expression in the heart, revealing cardiac tissue to be an extra-renal source of EPO. Indeed, primary cardiomyocytes and HL-1 cardiac cells both induce Epo gene expression when exposed to low O(2 tension in a HIF-dependent manner. Thus, as well as demonstrating the potential of dietary tamoxifen administration for gene inactivation studies in UBC-Cre-ER(T2 mouse lines, this data provides evidence of a cardiac oxygen-sensing VHL/HIF/EPO pathway in adult mice.

  19. 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.

  20. 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...

  1. Multimodal doxorubicin loaded magnetic nanoparticles for VEGF targeted theranostics of breast cancer.

    Science.gov (United States)

    Semkina, Alevtina S; Abakumov, Maxim A; Skorikov, Alexander S; Abakumova, Tatiana O; Melnikov, Pavel A; Grinenko, Nadejda F; Cherepanov, Sergey A; Vishnevskiy, Daniil A; Naumenko, Victor A; Ionova, Klavdiya P; Majouga, Alexander G; Chekhonin, Vladimir P

    2018-05-03

    In presented paper we have developed new system for cancer theranostics based on vascular endothelial growth factor (VEGF) targeted magnetic nanoparticles. Conjugation of anti-VEGF antibodies with bovine serum albumin coated PEGylated magnetic nanoparticles allows for improved binding with murine breast adenocarcinoma 4T1 cell line and facilitates doxorubicin delivery to tumor cells. It was shown that intravenous injection of doxorubicin loaded VEGF targeted nanoparticles increases median survival rate of mice bearing 4T1 tumors up to 50%. On the other hand magnetic resonance imaging (MRI) of 4T1 tumors 24 h after intravenous injection showed accumulation of nanoparticles in tumors, thus allowing simultaneous cancer therapy and diagnostics. Copyright © 2018. Published by Elsevier Inc.

  2. 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.

  3. Galectin-3 disruption impaired tumoral angiogenesis by reducing VEGF secretion from TGFβ1-induced macrophages

    International Nuclear Information System (INIS)

    Machado, Camila Maria Longo; Andrade, Luciana Nogueira Sousa; Teixeira, Verônica Rodrigues; Costa, Fabrício Falconi; Melo, Camila Morais; Santos, Sofia Nascimento dos; Nonogaki, Suely; Liu, Fu-Tong; Bernardes, Emerson Soares; Camargo, Anamaria Aranha; Chammas, Roger

    2014-01-01

    In order to study the role of galectin-3 in tumor angiogenesis associated with tumor-associated macrophages (TAM) and tumor parenchyma, the galectin-3 expression was reconstituted in Tm1 melanoma cell line that lacks this protein. Galectin-3-expressing cells (Tm1G3) and mock-vector transfected cells (Tm1N3) were injected into wild-type (WT) and galectin-3 knockout (KO) C57Bl/6 mice. Tumors originated from Tm1G3 were larger in tumor volume with enlarged functional vessels, decreased necrotic areas, and increased vascular endothelial growth factor (VEGF) protein levels. Galectin-3-nonexpressing-cells injected into WT and KO showed increased levels of transforming growth factor beta 1 (TGFβ1) and, in WT animals this feature was also accompanied by increased VEGFR2 expression and its phosphorylation. In KO animals, tumors derived from galectin-3-expressing cells were infiltrated by CD68 + -cells, whereas in tumors derived from galectin-3-nonexpressing-cells, CD68 + cells failed to infiltrate tumors and accumulated in the periphery of the tumor mass. In vitro studies showed that Tm1G3 secreted more VEGF than Tm1N3 cells. In the latter case, TGFβ1 induced VEGF production. Basal secretion of VEGF was higher in WT-bone marrow-derived macrophages (BMDM) than in KO-BMDM. TGFβ1 induced secretion of VEGF only in WT-BMDM. Tm1G3-induced tumors had the Arginase I mRNA increased, which upregulated alternative macrophage (M2)/TAM induction. M2 stimuli, such as interleukin-4 (IL4) and TGFβ1, increased Arginase I protein levels and galectin-3 expression in WT- BMDM, but not in cells from KO mice. Hence, we report that galectin-3 disruption in tumor stroma and parenchyma decreases angiogenesis through interfering with the responses of macrophages to the interdependent VEGF and TGFβ1 signaling pathways

  4. Changes in VEGF expression and DNA synthesis in hepatocytes from hepatectomized and tumour-bearing mice.

    Science.gov (United States)

    García, Marcela N; Andrini, Laura B; Inda, Ana María; Ronderos, Jorge R; Hijano, Julio C; Errecalde, Ana Lía

    2010-02-05

    Transplanted tumours could modify the intensity and temporal distribution of the cellular proliferation in normal cell populations, and partial hepatectomy alters the serum concentrations of substances involved in cellular proliferation, leading to the compensatory liver hyperplasia. The following experiments were designed in order to study the SI (S-phase index) and VEGF (vascular endothelial growth factor) expression in regenerating liver (after partial hepatectomy) of adult male mice bearing a hepatocellular carcinoma, throughout one complete circadian cycle. We used adult male C3H/S-strain mice. After an appropriate period of synchronization, the C3H/S-histocompatible ES2a hepatocellular carcinoma was grafted into the subcutaneous tissue of each animal's flank. To determine the index of SI and VEGF expression of hepatocytes, we used immunohistochemistry. The animals were divided into two experimental groups: Group I, control, hepatectomized animals; Group II, hepatectomized tumour-bearing animals. The statistical analysis of SI and VEGF expression was performed using Anova and Tukey as a postcomparison test. The results show that in the second group, the curve of SI changes the time points for maximum and minimum activity, and the peak of VEGF expression appears before the first group. In conclusion, in the hepatectomized mice, the increases of hepatic proliferation, measured by the SI index, may produce a rise in VEGF expression with the object of generating a vascular network for hepatic regeneration. Lastly, as we have mentioned, in hepatectomized and tumour-bearing mice, the peak of VEGF expression appears before the one of DNA synthesis.

  5. Association of mast cell-derived VEGF and proteases in Dengue shock syndrome.

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    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.

  6. The impact of KRAS mutations on VEGF-A production and tumour vascular network

    International Nuclear Information System (INIS)

    Figueras, Agnès; Arbos, Maria Antonia; Quiles, Maria Teresa; Viñals, Francesc; Germà, Josep Ramón; Capellà, Gabriel

    2013-01-01

    The malignant potential of tumour cells may be influenced by the molecular nature of KRAS mutations being codon 13 mutations less aggressive than codon 12 ones. Their metabolic profile is also different, with an increased anaerobic glycolytic metabolism in cells harbouring codon 12 KRAS mutations compared with cells containing codon 13 mutations. We hypothesized that this distinct metabolic behaviour could be associated with different HIF-1α expression and a distinct angiogenic profile. Codon13 KRAS mutation (ASP13) or codon12 KRAS mutation (CYS12) NIH3T3 transfectants were analyzed in vitro and in vivo. Expression of HIF-1α, and VEGF-A was studied at RNA and protein levels. Regulation of VEGF-A promoter activity was assessed by means of luciferase assays using different plasmid constructs. Vascular network was assessed in tumors growing after subcutaneous inoculation. Non parametric statistics were used for analysis of results. Our results show that in normoxic conditions ASP13 transfectants exhibited less HIF-1α protein levels and activity than CYS12. In contrast, codon 13 transfectants exhibited higher VEGF-A mRNA and protein levels and enhanced VEGF-A promoter activity. These differences were due to a differential activation of Sp1/AP2 transcription elements of the VEGF-A promoter associated with increased ERKs signalling in ASP13 transfectants. Subcutaneous CYS12 tumours expressed less VEGF-A and showed a higher microvessel density (MVD) than ASP13 tumours. In contrast, prominent vessels were only observed in the latter. Subtle changes in the molecular nature of KRAS oncogene activating mutations occurring in tumour cells have a major impact on the vascular strategy devised providing with new insights on the role of KRAS mutations on angiogenesis

  7. Targeting VEGF-B as a novel treatment for insulin resistance and type 2 diabetes.

    Science.gov (United States)

    Hagberg, Carolina E; Mehlem, Annika; Falkevall, Annelie; Muhl, Lars; Fam, Barbara C; Ortsäter, Henrik; Scotney, Pierre; Nyqvist, Daniel; Samén, Erik; Lu, Li; Stone-Elander, Sharon; Proietto, Joseph; Andrikopoulos, Sofianos; Sjöholm, Ake; Nash, Andrew; Eriksson, Ulf

    2012-10-18

    The prevalence of type 2 diabetes is rapidly increasing, with severe socioeconomic impacts. Excess lipid deposition in peripheral tissues impairs insulin sensitivity and glucose uptake, and has been proposed to contribute to the pathology of type 2 diabetes. However, few treatment options exist that directly target ectopic lipid accumulation. Recently it was found that vascular endothelial growth factor B (VEGF-B) controls endothelial uptake and transport of fatty acids in heart and skeletal muscle. Here we show that decreased VEGF-B signalling in rodent models of type 2 diabetes restores insulin sensitivity and improves glucose tolerance. Genetic deletion of Vegfb in diabetic db/db mice prevented ectopic lipid deposition, increased muscle glucose uptake and maintained normoglycaemia. Pharmacological inhibition of VEGF-B signalling by antibody administration to db/db mice enhanced glucose tolerance, preserved pancreatic islet architecture, improved β-cell function and ameliorated dyslipidaemia, key elements of type 2 diabetes and the metabolic syndrome. The potential use of VEGF-B neutralization in type 2 diabetes was further elucidated in rats fed a high-fat diet, in which it normalized insulin sensitivity and increased glucose uptake in skeletal muscle and heart. Our results demonstrate that the vascular endothelium can function as an efficient barrier to excess muscle lipid uptake even under conditions of severe obesity and type 2 diabetes, and that this barrier can be maintained by inhibition of VEGF-B signalling. We propose VEGF-B antagonism as a novel pharmacological approach for type 2 diabetes, targeting the lipid-transport properties of the endothelium to improve muscle insulin sensitivity and glucose disposal.

  8. Ligand-receptor assay for evaluation of functional activity of human recombinant VEGF and VEGFR-1 extracellular fragment.

    Science.gov (United States)

    Leopol'd, A V; Baklaushev, V P; Korchagina, A A; Shein, S A; Grinenko, N F; Pavlov, K A; Ryabukhin, I A; Chekhonin, V P

    2012-04-01

    cDNA encoding VEGF and Ig-like extracellular domains 2-4 of VEGFR-1 (sFlt-1(2-4)) were cloned into prokaryotic expression vectors pET32a and pQE60. Recombinant proteins were purified (metal affinity chromatography) and renatured. Chemiluminescent study for the interaction of recombinant VEGF and sFlt-1(2-4) showed that biotinylated VEGF specifically binds to the polystyrene-immobilized receptor extracellular fragment. Biotinylated recombinant sFlt-1 interacts with immobilized VEGF. Analysis of the interaction of immobilized recombinant VEGFR-1 and VEGF with C6 glioma cells labeled with CFDA-SE (vital fluorescent dye) showed that recombinant VEGFR-1 also binds to native membrane-associated VEGF. Recombinant VEGF was shown to bind to specific receptors expressed on the surface of C6 glioma cells. Functional activity of these proteins was confirmed by ligand-receptor assay for VEGF and VEGFR-1 (sFlt-1) and quantitative chemiluminescent detection.

  9. Bone marrow stromal cells with a combined expression of BMP-2 and VEGF-165 enhanced bone regeneration

    International Nuclear Information System (INIS)

    Xiao Caiwen; Zhou Huifang; Fu Yao; Gu Ping; Fan Xianqun; Liu Guangpeng; Zhang Peng; Hou Hongliang; Tang Tingting

    2011-01-01

    Bone graft substitutes with osteogenic factors alone often exhibit poor bone regeneration due to inadequate vascularization. Combined delivery of osteogenic and angiogenic factors from biodegradable scaffolds may enhance bone regeneration. We evaluated the effects of bone morphogenetic protein 2 (BMP2) and vascular endothelial growth factor (VEGF), combined with natural coral scaffolds, on the repair of critical-sized bone defects in rabbit orbits. In vitro expanded rabbit bone marrow stromal cells (BMSCs) were transfected with human BMP2 and VEGF165 genes. Target protein expression and osteogenic differentiation were confirmed after gene transduction. Rabbit orbital defects were treated with a coral scaffold loaded with BMP2-transduced and VEGF-transduced BMSCs, BMP2-expressing BMSCs, VEGF-expressing BMSCs, or BMSCs without gene transduction. Volume and density of regenerated bone were determined by micro-computed tomography at 4, 8, and 16 weeks after implantation. Neovascularity, new bone deposition rate, and new bone formation were measured by immunostaining, tetracycline and calcein labelling, and histomorphometric analysis at different time points. The results showed that VEGF increased blood vessel formation relative to groups without VEGF. Combined delivery of BMP2 and VEGF increased new bone deposition and formation, compared with any single factor. These findings indicate that mimicking the natural bone development process by combined BMP2 and VEGF delivery improves healing of critical-sized orbital defects in rabbits.

  10. VEGF system expression by immunohistochemistry and real-time RT-PCR study on collared peccary placenta

    DEFF Research Database (Denmark)

    Santos, Tatiana C.; Oliveira, Moacir F.; Papa, Paula C.

    2014-01-01

    Vascular endothelial growth factor (VEGF) is known to induce endothelial cell proliferation, to promote cell migration, and to inhibit apoptosis, thus playing a central role in angiogenesis and in the regulation of vasculogenesis. The expression of the VEGF-ligand receptor system was studied in t...

  11. Combined immunotherapy of breast cancer with EGF and VEGF vaccines from DNA shuffling in a mouse model.

    Science.gov (United States)

    Jin, Dong; Yu, Xin; Chen, Bing; Li, Zhitao; Ding, Jia; Zhao, Xiuyun; Qi, Gaofu

    2017-06-01

    Development of EGF and VEGF vaccines with high antigenicity for combined immunotherapy of EGF-EGFR signaling-dependent epithelial tumors such as breast cancer. EGF genes from mouse, human and chicken were randomly assembled to chimeric genes by DNA shuffling, then a chimeric EGF was selected out by PCR, SDS-PAGE and immunization for combined immunotherapy of breast cancer with a previously constructed chimeric VEGF vaccine from shuffling. Combined vaccination with chimeric EGF and VEGF from shuffling could induce high titer of antibodies against EGF and VEGF to inhibit tumor growth and angiogenesis, and improve the survival rate of mice with breast cancer. Combined vaccination with EGF and VEGF from shuffling showed better immunotherapy on EGF-EGFR signaling-dependent epithelial tumors such as breast cancer than the single-agent EGF vaccination.

  12. Alternative splicing of TIA-1 in human colon cancer regulates VEGF isoform expression, angiogenesis, tumour growth and bevacizumab resistance.

    Science.gov (United States)

    Hamdollah Zadeh, Maryam A; Amin, Elianna M; Hoareau-Aveilla, Coralie; Domingo, Enric; Symonds, Kirsty E; Ye, Xi; Heesom, Katherine J; Salmon, Andrew; D'Silva, Olivia; Betteridge, Kai B; Williams, Ann C; Kerr, David J; Salmon, Andrew H J; Oltean, Sebastian; Midgley, Rachel S; Ladomery, Michael R; Harper, Steven J; Varey, Alexander H R; Bates, David O

    2015-01-01

    The angiogenic capability of colorectal carcinomas (CRC), and their susceptibility to anti-angiogenic therapy, is determined by expression of vascular endothelial growth factor (VEGF) isoforms. The intracellular protein T-cell Intracellular Antigen (TIA-1) alters post-transcriptional RNA processing and binds VEGF-A mRNA. We therefore tested the hypothesis that TIA-1 could regulate VEGF-A isoform expression in colorectal cancers. TIA-1 and VEGF-A isoform expression was measured in colorectal cancers and cell lines. We discovered that an endogenous splice variant of TIA-1 encoding a truncated protein, short TIA-1 (sTIA-1) was expressed in CRC tissues and invasive K-Ras mutant colon cancer cells and tissues but not in adenoma cell lines. sTIA-1 was more highly expressed in CRC than in normal tissues and increased with tumour stage. Knockdown of sTIA-1 or over-expression of full length TIA-1 (flTIA-1) induced expression of the anti-angiogenic VEGF isoform VEGF-A165b. Whereas flTIA-1 selectively bound VEGF-A165 mRNA and increased translation of VEGF-A165b, sTIA-1 prevented this binding. In nude mice, xenografted colon cancer cells over-expressing flTIA-1 formed smaller, less vascular tumours than those expressing sTIA-1, but flTIA-1 expression inhibited the effect of anti-VEGF antibodies. These results indicate that alternative splicing of an RNA binding protein can regulate isoform specific expression of VEGF providing an added layer of complexity to the angiogenic profile of colorectal cancer and their resistance to anti-angiogenic therapy. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  13. Endocrine gland-derived endothelial growth factor (EG-VEGF) is a potential novel regulator of human parturition.

    Science.gov (United States)

    Dunand, C; Hoffmann, P; Sapin, V; Blanchon, L; Salomon, A; Sergent, F; Benharouga, M; Sabra, S; Guibourdenche, J; Lye, S J; Feige, J J; Alfaidy, N

    2014-09-01

    EG-VEGF is an angiogenic factor that we identified as a new placental growth factor during human pregnancy. EG-VEGF is also expressed in the mouse fetal membrane (FM) by the end of gestation, suggesting a local role for this protein in the mechanism of parturition. However, injection of EG-VEGF to gravid mice did not induce labor, suggesting a different role for EG-VEGF in parturition. Here, we searched for its role in the FM in relation to human parturition. Human pregnant sera and total FM, chorion, and amnion were collected during the second and third trimesters from preterm no labor, term no labor, and term labor patients. Primary human chorion trophoblast and FM explants cultures were also used. We demonstrate that circulating EG-VEGF increased toward term and significantly decreased at the time of labor. EG-VEGF production was higher in the FM compared to placentas matched for gestational age. Within the FM, the chorion was the main source of EG-VEGF. EG-VEGF receptors, PROKR1 and PROKR2, were differentially expressed within the FM with increased expression toward term and an abrupt decrease with the onset of labor. In chorion trophoblast and FM explants collected from nonlaboring patients, EG-VEGF decreased metalloproteinase-2 and -9 activities and increased PGDH (prostaglandin-metabolizing enzyme) expression. Altogether these data demonstrate that EG-VEGF is a new cytokine that acts locally to ensure FM protection in late pregnancy. Its fine contribution to the initiation of human labor is exhibited by the abrupt decrease in its levels as well as a reduction in its receptors. © 2014 by the Society for the Study of Reproduction, Inc.

  14. Revisiting the role of hCG: new regulation of the angiogenic factor EG-VEGF and its receptors.

    Science.gov (United States)

    Brouillet, S; Hoffmann, P; Chauvet, S; Salomon, A; Chamboredon, S; Sergent, F; Benharouga, M; Feige, J J; Alfaidy, N

    2012-05-01

    Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an angiogenic factor reported to be specific for endocrine tissues, including the placenta. Its biological activity is mediated via two G protein-coupled receptors, prokineticin receptor 1 (PROKR1) and prokineticin receptor 2 (PROKR2). We have recently shown that (i) EG-VEGF expression peaks between the 8th and 11th weeks of gestation, (ii) its mRNA and protein levels are up-regulated by hypoxia, (iii) EG-VEGF is a negative regulator of trophoblast invasion and (iv) its circulating levels are increased in preeclampsia (PE), the most threatening pathology of pregnancy. Here, we investigated the regulation of the expression of EG-VEGF and its receptors by hCG, a key pregnancy hormone that is also deregulated in PE. During the first trimester of pregnancy, hCG and EG-VEGF exhibit the same pattern of expression, suggesting that EG-VEGF is potentially regulated by hCG. Both placental explants (PEX) and primary cultures of trophoblasts from the first trimester of pregnancy were used to investigate this hypothesis. Our results show that (i) LHCGR, the hCG receptor, is expressed both in cyto- and syncytiotrophoblasts, (ii) hCG increases EG-VEGF, PROKR1 and PROKR2 mRNA and protein expression in a dose- and time-dependent manner, (iii) hCG increases the release of EG-VEGF from PEX conditioned media, (iv) hCG effects are transcriptional and post-transcriptional and (v) the hCG effects are mediated by cAMP via cAMP response elements present in the EG-VEGF promoter region. Altogether, these results demonstrate a new role for hCG in the regulation of EG-VEGF and its receptors, an emerging regulatory system in placental development.

  15. Huh-7 cell line as an alternative cultural model for the production of human like erythropoietin (EPO

    Directory of Open Access Journals (Sweden)

    Kausar Humera

    2011-11-01

    Full Text Available Abstract Background and Aims Erythropoietin (EPO is a glycoprotein hormone which is required to regulate the production of red blood cells. Deficiency of EPO is known to cause anemia in chronically infected renal patients and they require regular blood transfusion. Availability of recombinant EPO has eliminated the need for blood transfusion and now it is extensively used for the treatment of anemia. Glycosylation of erythropoietin is essential for its secretion, stability, protein conformation and biological activity. However, maintenance of human like glycosylation pattern during manufacturing of EPO is a major challenge in biotechnology. Currently, Chinese hamster ovary (CHO cell line is used for the commercial production of erythropoietin but this cell line does not maintain glycosylation resembling human system. With the trend to eliminate non-human constituent from biopharmaceutical products, as a preliminary approach, we have investigated the potential of human hepatoma cell line (Huh-7 to produce recombinant EPO. Materials and methods Initially, the secretory signal and Kozak sequences was added before the EPO mature protein sequence using overlap extension PCR technique. PCR-amplified cDNA fragments of EPO was inserted into mammalian expression vector under the control of the cytomegalovirus (CMV promoter and transiently expressed in CHO and Huh-7 cell lines. After RT-PCR analysis, ELISA and Western blotting was performed to verify the immunochemical properties of secreted EPO. Results Addition of secretory signal and Kozak sequence facilitated the extra-cellular secretion and enhanced the expression of EPO protein. Significant expression (P Conclusion Huh-7 cell line has a great potential to produce glycosylated EPO, suggesting the use of this cell line to produce glycoproteins of the therapeutic importance resembling to the natural human system.

  16. Protective effect of bone marrow mesenchymal stem cells combined with erythropoietin therapy on spinal cord injury rat model

    Directory of Open Access Journals (Sweden)

    Peng Xie

    2016-01-01

    Full Text Available Objective: To study the protective effect of bone marrow mesenchymal stem cells combined with erythropoietin therapy on spinal cord injury rat model. Methods: SD rats were selected as experimental animals, spinal cord injury rat model was built by striking spinal cord with Hatteras Instruments PCI3000, and model rats were divided into control group, bone marrow mesenchymal stem cells (BMSCs group, erythropoietin (EPO group and BMSCs combined with EPO group according to different treatment methods. Then number of apoptotic cells in spinal cord tissue, contents of neural markers and neurotrophic factors as well as expression of apoptosis and injury molecules was detected. Results: Number of apoptotic cells as well as mRNA contents of Caspase-3 and c-fos of BMSCs group, EPO group and BMSCs+EPO group was lower than those of control group, and number of apoptotic cells as well as mRNA contents of Caspase-3 and c-fos of BMSCs+EPO group were lower than those of BMSCs group and EPO group; mRNA contents of NF-200 and MBP as well as protein contents of NGF and BDNF in spinal cord tissue of BMSCs group, EPO group and BMSCs+EPO group were higher than those of control group, and mRNA contents of NF-200 and MBP as well as protein contents of NGF and BDNF in spinal cord tissue of BMSCs+EPO group were higher than those of BMSCs group and EPO group. Conclusions: Bone marrow mesenchymal stem cells combined with erythropoietin therapy can inhibit cell apoptosis in the injured spinal cord tissue, increase neurotrophic factor levels and inhibit apoptosis and injury molecule expression; it has protective effect on spinal cord injury.

  17. Regulation of human feto-placental endothelial barrier integrity by vascular endothelial growth factors: competitive interplay between VEGF-A165a, VEGF-A165b, PIGF and VE-cadherin.

    Science.gov (United States)

    Pang, Vincent; Bates, David O; Leach, Lopa

    2017-12-01

    The human placenta nourishes and protects the developing foetus whilst influencing maternal physiology for fetal advantage. It expresses several members of the vascular endothelial growth factor (VEGF) family including the pro-angiogenic/pro-permeability VEGF-A 165 a isoform, the anti-angiogenic VEGF-A 165 b, placental growth factor (PIGF) and their receptors, VEGFR1 and VEGFR2. Alterations in the ratio of these factors during gestation and in complicated pregnancies have been reported; however, the impact of this on feto-placental endothelial barrier integrity is unknown. The present study investigated the interplay of these factors on junctional occupancy of VE-cadherin and macromolecular leakage in human endothelial monolayers and the perfused placental microvascular bed. Whilst VEGF-A 165 a (50 ng/ml) increased endothelial monolayer albumin permeability ( P 0.05) or PlGF ( P >0.05) did not. Moreover, VEGF-A 165 b (100 ng/ml; P 0.05) inhibited VEGF-A 165 a-induced permeability when added singly. PlGF abolished the VEGF-A 165 b-induced reduction in VEGF-A 165 a-mediated permeability ( P >0.05); PlGF was found to compete with VEGF-A 165 b for binding to Flt-1 at equimolar affinity. Junctional occupancy of VE-cadherin matched alterations in permeability. In the perfused microvascular bed, VEGF-A 165 b did not induce microvascular leakage but inhibited and reversed VEGF-A 165 a-induced loss of junctional VE-cadherin and tracer leakage. These results indicate that the anti-angiogenic VEGF-A 165 b isoform does not increase permeability in human placental microvessels or HUVEC primary cells and can interrupt VEGF-A 165 a-induced permeability. Moreover, the interplay of these isoforms with PIGF (and s-flt1) suggests that the ratio of these three factors may be important in determining the placental and endothelial barrier in normal and complicated pregnancies. © 2017 The Author(s).

  18. K20E, an oxidative-coupling compound of methyl caffeate, exhibits anti-angiogenic activities through down-regulations of VEGF and VEGF receptor-2

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Chun-Hsu [Department of Pharmacy, Taipei Medical University, Taipei 11031, Taiwan (China); Lin, Wen-Hsin; Chien, Yi-Chung; Liu, Fon-Chang; Sheu, Ming-Jyh [School of Pharmacy, China Medical University, Taichung 40402, Taiwan (China); Kuo, Yueh-Hsiung, E-mail: kuoyh@mail.cmu.edu.tw [Tsuzuki Institute for Traditional Medicine, China Medical University, Taichung 40402, Taiwan (China); Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, China Medical University, Taichung 40402, Taiwan (China); Department of Biotechnology, Asia University, Taichung 41354, Taiwan (China); Wu, Chieh-Hsi, E-mail: chhswu@tmu.edu.tw [Department of Pharmacy, Taipei Medical University, Taipei 11031, Taiwan (China); School of Pharmacy, China Medical University, Taichung 40402, Taiwan (China); Department of Biological Science and Technology, China Medical University, Taichung 40402, Taiwan (China)

    2015-01-15

    Anti-angiogenesis is one of the most popular clinical interventions for cancer chemotherapy. A series of synthesized derivative of methyl caffeate were used to evaluate the anti-angiogenic activity and to investigate possible pharmacological mechanisms in the present study. The most potent anti-angiogenic compound was evaluated in the experiments of murine allograft tumor model and Matrigel plug assay as well as cell models in the human umbilical vascular endothelial cells (HUVECs) and the LLC1 lung cancer cells. Our results suggested that K20E suppressed the tumor growth in the allograft tumor model and exhibited anti-angiogenic activity in Matrigel plug assay. Besides, HUVEC viability was found to be significantly reduced by arresting cell cycle at G{sub 2}/M phase and apoptosis. Cell migration, invasion, and tube formation of the HUVECs were also markedly suppressed by K20E treatment. K20E largely down-regulated the intracellular and secreted vascular endothelial growth factor (VEGF) in the LLC1 cancer cells. Besides, VEGF receptor-2 (VEGFR-2) and its downstream signaling cascades (AKT-mTOR and MEK1/2-ERK1/2) as well as gelatinases were all evidently reduced in the HUVECs treated with K20E. Inversely, K20E can up-regulate the expression levels of p53 and p21 proteins in the HUVECs. Based on these results, our study suggested that K20E possessed inhibiting angiogenesis through regulation of VEGF/VEGFR-2 and its downstream signaling cascades in the vascular endothelial cells (VECs). - Highlights: • K20E is an oxidative-coupling compound of methyl caffeate. • K20E exhibits anti-tumor and anti-angiogenesis effects. • K20E suppresses the expressions of VEGF and VEGF receptor-2 (VEGFR-2) proteins. • K20E deactivates VEGFR-2-mediated downstream signaling pathways to inhibit angiogenesis. • K20E up-regulates p53-p21 pathway to induce apoptosis and cell arrest at G2/M phase.

  19. Simultaneous Expression from Both the Sense and Antisense Strand of the Erythropoietin Receptor Gene Mitigates Acute Lung Injury

    Science.gov (United States)

    2017-09-01

    concept efficacy that increasing EpoR or RopE expression by cDNA delivery to lung cells in vitro enhances cytoprotection against hyperoxia-induced injury...oxidative damage, cell culture, rodent model, inhalation cDNA delivery, sense and antisense erythropoietin receptor transcripts 16. SECURITY...prevention of acute lung injury. 1-6 50% Subtask 1: Prepare plasmid cDNA of EpoR and RopE in nanoparticle formulation. 1 Completed 06.2017 Subtask 2

  20. Pharmacodynamically optimized erythropoietin treatment combined with phlebotomy reduction predicted to eliminate blood transfusions in selected preterm infants.

    Science.gov (United States)

    Rosebraugh, Matthew R; Widness, John A; Nalbant, Demet; Cress, Gretchen; Veng-Pedersen, Peter

    2014-02-01

    Preterm very-low-birth-weight (VLBW) infants weighing eliminated by reducing laboratory blood loss in combination with pharmacodynamically optimized erythropoietin (Epo) treatment. Twenty-six VLBW ventilated infants receiving RBCTx were studied during the first month of life. RBCTx simulations were based on previously published RBCTx criteria and data-driven Epo pharmacodynamic optimization of literature-derived RBC life span and blood volume data corrected for phlebotomy loss. Simulated pharmacodynamic optimization of Epo administration and reduction in phlebotomy by ≥ 55% predicted a complete elimination of RBCTx in 1.0-1.5 kg infants. In infants 1.0 kg.

  1. 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

    these findings apply to humans remains unknown. We exposed healthy young subjects to hypoxia (equivalent to 3800 m) and measured EPO in arterial and jugular venous plasma and in cerebrospinal fluid. To examine the role of the skin for EPO production during hypoxia, subjects were exposed to 8 h of hypobaric......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...

  2. Design of a variant of vascular endothelial growth factor-A (VEGF-A) antagonizing KDR/Flk-1 and Flt-1.

    NARCIS (Netherlands)

    Leenders, W.P.J.; Lubsen, N.H.; Altena, M.C. van; Clauss, M.; Deckers, M.; Lowik, C.W.G.M.; Breier, G.; Ruiter, D.J.; Waal, R.M.W. de

    2002-01-01

    Because of its central role in pathological angiogenesis, vascular endothelial growth factor (VEGF) has become a major target for anti-angiogenic therapies. We report here the construction of a heterodimeric antagonistic VEGF variant (HD-VEGF). In this antagonist, binding domains for the

  3. Intermittent fasting promotes adipose thermogenesis and metabolic homeostasis via VEGF-mediated alternative activation of macrophage.

    Science.gov (United States)

    Kim, Kyoung-Han; Kim, Yun Hye; Son, Joe Eun; Lee, Ju Hee; Kim, Sarah; Choe, Min Seon; Moon, Joon Ho; Zhong, Jian; Fu, Kiya; Lenglin, Florine; Yoo, Jeong-Ah; Bilan, Philip J; Klip, Amira; Nagy, Andras; Kim, Jae-Ryong; Park, Jin Gyoon; Hussein, Samer Mi; Doh, Kyung-Oh; Hui, Chi-Chung; Sung, Hoon-Ki

    2017-11-01

    Intermittent fasting (IF), a periodic energy restriction, has been shown to provide health benefits equivalent to prolonged fasting or caloric restriction. However, our understanding of the underlying mechanisms of IF-mediated metabolic benefits is limited. Here we show that isocaloric IF improves metabolic homeostasis against diet-induced obesity and metabolic dysfunction primarily through adipose thermogenesis in mice. IF-induced metabolic benefits require fasting-mediated increases of vascular endothelial growth factor (VEGF) expression in white adipose tissue (WAT). Furthermore, periodic adipose-VEGF overexpression could recapitulate the metabolic improvement of IF in non-fasted animals. Importantly, fasting and adipose-VEGF induce alternative activation of adipose macrophage, which is critical for thermogenesis. Human adipose gene analysis further revealed a positive correlation of adipose VEGF-M2 macrophage-WAT browning axis. The present study uncovers the molecular mechanism of IF-mediated metabolic benefit and suggests that isocaloric IF can be a preventive and therapeutic approach against obesity and metabolic disorders.

  4. Diagnostic value of urinary CK-20 RNA and VEGF in bladder cancer ...

    African Journals Online (AJOL)

    The present study was carried out to evaluate the diagnostic value of urinary cytokeratin 20 (CK-20) RNA and vascular endothelial growth factor (VEGF) in comparison with urine cytology in the detection of bladder cancer. This study included 80 patients with bladder cancer, 20 patients with bilharzial bladder lesions and 20 ...

  5. Intermittent fasting promotes adipose thermogenesis and metabolic homeostasis via VEGF-mediated alternative activation of macrophage

    Science.gov (United States)

    Kim, Kyoung-Han; Kim, Yun Hye; Son, Joe Eun; Lee, Ju Hee; Kim, Sarah; Choe, Min Seon; Moon, Joon Ho; Zhong, Jian; Fu, Kiya; Lenglin, Florine; Yoo, Jeong-Ah; Bilan, Philip J; Klip, Amira; Nagy, Andras; Kim, Jae-Ryong; Park, Jin Gyoon; Hussein, Samer MI; Doh, Kyung-Oh; Hui, Chi-chung; Sung, Hoon-Ki

    2017-01-01

    Intermittent fasting (IF), a periodic energy restriction, has been shown to provide health benefits equivalent to prolonged fasting or caloric restriction. However, our understanding of the underlying mechanisms of IF-mediated metabolic benefits is limited. Here we show that isocaloric IF improves metabolic homeostasis against diet-induced obesity and metabolic dysfunction primarily through adipose thermogenesis in mice. IF-induced metabolic benefits require fasting-mediated increases of vascular endothelial growth factor (VEGF) expression in white adipose tissue (WAT). Furthermore, periodic adipose-VEGF overexpression could recapitulate the metabolic improvement of IF in non-fasted animals. Importantly, fasting and adipose-VEGF induce alternative activation of adipose macrophage, which is critical for thermogenesis. Human adipose gene analysis further revealed a positive correlation of adipose VEGF-M2 macrophage-WAT browning axis. The present study uncovers the molecular mechanism of IF-mediated metabolic benefit and suggests that isocaloric IF can be a preventive and therapeutic approach against obesity and metabolic disorders. PMID:29039412

  6. Targeting VEGF in canine oxygen-induced retinopathy - a model for human retinopathy of prematurity

    Directory of Open Access Journals (Sweden)

    McLeod DS

    2016-05-01

    Full Text Available D Scott McLeod, Gerard A Lutty Department of Ophthalmology, Wilmer Ophthalmological Institute, Johns Hopkins Hospital, Baltimore, MD, USA Abstract: Development of the dog superficial retinal vasculature is similar to the mechanism of human retinal vasculature development; they both develop by vasculogenesis, differentiation, and assembly of vascular precursors called angioblasts. Canine oxygen-induced retinopathy (OIR was first developed by Arnall Patz in an effort to experimentally determine the effects of hyperoxia on the development of the retinal vasculature. The canine OIR model has many characteristics in common with human retinopathy of prematurity. Exposure of 1-day-old dogs to hyperoxia for 4 days causes a vaso-obliteration throughout the retina. Vasoproliferation, after the animals have returned to room air, is robust. The initial small preretinal neovascular formations anastomose to form large preretinal membranes that eventually cause tractional retinal folds. The end-stage pathology of the canine model is similar to stage IV human retinopathy of prematurity. Therefore, canine OIR is an excellent forum to evaluate the response to drugs targeting VEGF and its receptors. Evaluation of an antibody to VEGF-R2 and the VEGF-Trap demonstrated that doses should be titered down so that preretinal neovascularization is inhibited but retinal revascularization is able to proceed, vascularizing peripheral retina and preventing it from being a source of VEGF. Keywords: angioblasts, blood vessels, endothelial cells, oxygen, retinopathy, retina, vascular endothelial cell growth factor

  7. Canonical hedgehog signaling augments tumor angiogenesis by induction of VEGF-A in stromal perivascular cells

    Science.gov (United States)

    Chen, Weiwe