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Sample records for preischaemic erythropoietin administration

  1. Efficiency of recombinant erythropoietin administration in hemoglobinopathy H.

    PubMed

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

    2014-01-01

    Alpha-thalassemia is widely spread in human population and one of the most common types of α-thalassemia is hemoglobinopathy H which develops with mild microcytic hypochromic anemia, hepatosplenomegaly and jaundice. The basic method of anemia correction is blood transfusion. However this method has crucial deficiencies. As it is known recombinant erythropoetin (rEPO) contributes to erythroid proliferation and could be used for anemia treatment. The aim of the study was to qualify efficiency of administration rEPO in complex therapy of hemaglobinopathy H. Study involved irregularly transfused 14 patients with hemoglobinopathy H (2 males and 12 females). Control group included 30 healthy persons. Recombinant erythropoietin (Eprex) administrated hypodermically 10,000 units 3 times a week during 6 months. Average hemoglobin level before treatment was 62 g/l. Responses to the rEPO treatment varied from 9 to 70 g/l, 9 (64%) of patients had a good response, showed an increase in hemoglobin level more than 20 g/l. In 4 patients (29%) had a moderate response (10-20 g/l), but only in 1 (7%) patient occurred poor response. Changing the parameters of erithrocyte indices, hemoglobin fractions, serum iron and serum ferritin level are not statistically significant. It can be concluded that the use of rEPO in complex therapy of hemaglobinopathy H, leads to increased levels of hemoglobin and consequently reducing the need for blood transfusions.

  2. Erythropoietin

    PubMed Central

    Bunn, H. Franklin

    2013-01-01

    During the past century, few proteins have matched erythropoietin (Epo) in capturing the imagination of physiologists, molecular biologists, and, more recently, physicians and patients. Its appeal rests on its commanding role as the premier erythroid cytokine, the elegant mechanism underlying the regulation of its gene, and its remarkable impact as a therapeutic agent, arguably the most successful drug spawned by the revolution in recombinant DNA technology. This concise review will begin with a synopsis of the colorful history of this protein, culminating in its purification and molecular cloning. It then covers in more detail the contemporary understanding of Epo’s physiology as well as its structure and interaction with its receptor. A major part of this article focuses on the regulation of the Epo gene and the discovery of HIF, a transcription factor that plays a cardinal role in molecular adaptation to hypoxia. In the concluding section, a synopsis of Epo’s role in disorders of red blood cell production will be followed by an assessment of the remarkable impact of Epo therapy in the treatment of anemias, as well as concerns that provide a strong impetus for the development of even safer and more effective treatment. PMID:23457296

  3. Anti-erythropoietin and anti-thrombopoietin antibodies induced after administration of recombinant human erythropoietin.

    PubMed

    Shin, Sug Kyun; Pack, Seung Pil; Oh, Jin-Gyo; Kang, Nam Kyu; Chang, Myung Hee; Chung, Yoon Hee; Kim, Sung-Jo; Lee, Jong Wook; Heo, Tae-Hwe

    2011-12-01

    Recombinant human erythropoietin (rhEPO) has been successfully used for correcting renal anemia. However, recent studies have raised some concerns about the safety of rhEPO treatment due to its immunogenic side effect - pure red cell aplasia (PRCA). We now report a case of development of anti-EPO neutralizing antibodies (Abs) implicated in thrombocytopenia as well as erythrocytopenia. A 35-year-old man had a history of administering rhEPO (epoetin alfa, epoetin beta and darbepoetin alfa) for 2years to treat renal anemia. The hematological parameters were collected. Anti-EPO, anti-platelet, and anti-thrombopoietin (TPO) Ab assays were performed to test the presence of autoreactive Abs. After performing antibody assays due to severe resistance to rhEPO treatment, a high titer of anti-EPO neutralizing Abs was detected. However, unexpectedly, this patient also showed thrombocytopenia rather than PRCA. We investigated the cause of the marked thrombocytopenia and found anti-TPO Abs in patient serum. To our best knowledge, this is the first report of the development of anti-TPO Abs during rhEPO treatment for anemia.

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

    PubMed

    Faa, Armando; Faa, Gavino; Papalois, Apostolos; Obinu, Eleonora; Locci, Giorgia; Pais, Maria Elena; Lelovas, Pavlos; Barouxis, Dimitrios; Pantazopoulos, Charalampos; Vasileiou, Panagiotis V; Iacovidou, Nicoletta; Xanthos, Theodoros

    2016-01-01

    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.

  5. The role of excessive versus acute administration of erythropoietin in attenuating hepatic ischemia-reperfusion injury.

    PubMed

    Pappo, Orit; Ben-Ari, Ziv; Shevtsov, Evgeni; Avlas, Orna; Gassmann, Max; Ravid, Amiram; Cheporko, Yelena; Hochhauser, Edith

    2010-12-01

    Ischemia-reperfusion injury (I/R) is the main cause of primary graft nonfunction. Our aim was to evaluate the effect of excessive versus acute administration of erythropoietin (EPO) in attenuating the hepatic injury induced by I/R in mice. The effect of segmental (70%) hepatic ischemia was evaluated in a transgenic mouse line with constitutive overexpression of human EPO cDNA and in wild-type (WT) mice. Mice were randomly allocated to 5 main experimental groups: (i) WT-sham, (ii) WT ischemia, (iii) WT ischemia + recombinant human erythropoietin (rhEPO), (iv) transgenic-sham, and (v) transgenic ischemia. The EPO-pretreated mice showed a significant reduction in liver enzyme levels and intrahepatic caspase-3 activity and fewer apoptotic hepatocytes (p < 0.05 for all) compared with the WT untreated I/R group. EPO decreased c-Jun N-terminal kinase (JNK) phosphorylation and nuclear factor-κB (NF-κB) expression during I/R. In transgenic I/R livers, baseline histology showed diffused hepatic injury, and no significant beneficial effect was noted between the WT untreated and the transgenic I/R mice. In conclusion, acute pretreatment with EPO in WT mice attenuated in vivo I/R liver injury. However, in excessive EPO overexpression, the initial liver injury abolished the beneficial effect of EPO. These findings have important implications for the potential use of acute EPO in I/R injury during liver transplantation.

  6. Preclinical evaluation of erythropoietin administration in a model of radiation-induced kidney dysfunction

    SciTech Connect

    Andratschke, Nicolaus; Schnaitera, Andrea; Weber, Wolfgang A.; Caia, Lu; Schill, Sabine; Wiedenmann, Nicole; Schwaiger, Markus; Molls, Michael; Nieder, Carsten . E-mail: cnied@hotmail.com

    2006-04-01

    Purpose: To test whether the clinically available growth factor erythropoietin (EPO) influences radiation-induced normal-tissue damage in a model of kidney dysfunction. Methods: Animal experiments were conducted to test the role of EPO administration in a C3H mouse model of unilateral kidney irradiation with 6, 8, and 10 Gy and to assess the effects of 2 different dose levels of EPO. The kidney function was assessed before radiotherapy, as well as 19, 25, 31, and 37 weeks thereafter by means of {sup 99m}Tc-dimercaptosuccinat scans (static scintigraphy). Results: Concomitant EPO administration significantly increased the degree of radiation-induced kidney dysfunction. A dose of 2,000 IU/kg body weight per injection tended to cause more damage than the lower dose of 500 IU/kg. Conclusion: Administration of growth factors concomitant to radiotherapy might modify the development of kidney dysfunction. Although insulin-like growth factor-1 has previously been shown to protect the kidney, such an effect could not be demonstrated for EPO. The latter agent even increased the development of nephropathy.

  7. Late-onset blueberry muffin lesions following recombinant erythropoietin administration in a premature infant.

    PubMed

    Pandey, Vishal; Dummula, Krishna; Fraga, Garth; Parimi, Prabhu

    2012-10-01

    Recombinant erythropoietin is being used in premature population for anemia of prematurity. It is considered very safe in this population, although risks are still being evaluated. We report the first case of dermal erythropoiesis as a side effect of recombinant erythropoietin in an extremely prematurely born infant presenting with late-onset blueberry muffin lesions.

  8. Erythropoietin administration increases splenic erythroferrone protein content and liver TMPRSS6 protein content in rats.

    PubMed

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

    2017-02-28

    Erythroferrone (ERFE) and TMPRSS6 are important proteins in the regulation of iron metabolism. The objective of the study was to examine splenic ERFE and liver TMPRSS6 synthesis in rats treated with a combination of iron and erythropoietin (EPO). EPO was administered to female Wistar rats at 600U/day for four days, iron-pretreated rats received 150mg of iron before EPO treatment. Content of ERFE and TMPRSS6 proteins was determined by commercial antibodies. Iron pretreatment prevented the EPO-induced decrease in hepcidin expression. Content of phosphorylated SMAD 1,5,8 proteins was decreased in the liver by both EPO and iron plus EPO treatment. Fam132b expression in the spleen was increased both by EPO and iron plus EPO treatments; these treatments also significantly induced splenic Fam132a expression. ERFE protein content in the spleen was increased both by EPO and iron plus EPO to a similar extent. EPO administration increased TMPRSS6 content in the plasma membrane-enriched fraction of liver homogenate; in iron-pretreated rats, this increase was abolished. The results confirm that iron pretreatment prevents the EPO-induced decrease in liver Hamp expression. This effect probably occurs despite high circulating ERFE levels, since EPO-induced ERFE protein synthesis is not influenced by iron pretreatment.

  9. Erythropoietin administration partially prevents adipose tissue loss in experimental cancer cachexia models

    PubMed Central

    Penna, Fabio; Busquets, Silvia; Toledo, Miriam; Pin, Fabrizio; Massa, David; López-Soriano, Francisco J.; Costelli, Paola; Argilés, Josep M.

    2013-01-01

    Cancer-associated cachexia is characterized, among other symptoms, by a dramatic loss of both muscle and fat. In addition, the cachectic syndrome is often associated with anemia. The object of the present investigation was to assess the effects of erythropoietin (EPO) treatment on experimental cancer cachexia models. The results clearly show that, in addition to the improvement of the hematocrit, EPO treatment promoted a partial preservation of adipose tissue while exerting negligible effects on muscle loss. Administration of EPO to tumor-bearing animals resulted in a significant increase of lipoprotein lipase (LPL) activity in adipose tissue, suggesting that the treatment favored triacylglycerol (TAG) accumulation in the adipose tissue. In vitro experiments using both adipose tissue slices and 3T3-L1 adipocytes suggests that EPO is able to increase the lipogenic rate through the activation of its specific receptor (EPOR). This metabolic pathway, in addition to TAG uptake by LPL, may contribute to the beneficial effects of EPO on fat preservation in cancer cachexia. PMID:23966665

  10. Delayed administration of darbepoetin or erythropoietin protects against ischemic acute renal injury and failure.

    PubMed

    Johnson, D W; Pat, B; Vesey, D A; Guan, Z; Endre, Z; Gobe, G C

    2006-05-01

    Administration of human recombinant erythropoietin (EPO) at time of acute ischemic renal injury (IRI) inhibits apoptosis, enhances tubular epithelial regeneration, and promotes renal functional recovery. The present study aimed to determine whether darbepoetin-alfa (DPO) exhibits comparable renoprotection to that afforded by EPO, whether pro or antiapoptotic Bcl-2 proteins are involved, and whether delayed administration of EPO or DPO 6 h following IRI ameliorates renal dysfunction. The model of IRI involved bilateral renal artery occlusion for 45 min in rats (N = 4 per group), followed by reperfusion for 1-7 days. Controls were sham-operated. Rats were treated at time of ischemia or sham operation (T0), or post-treated (6 h after the onset of reperfusion, T6) with EPO (5000 IU/kg), DPO (25 mug/kg), or appropriate vehicle by intraperitoneal injection. Renal function, structure, and immunohistochemistry for Bcl-2, Bcl-XL, and Bax were analyzed. DPO or EPO at T0 significantly abrogated renal dysfunction in IRI animals (serum creatinine for IRI 0.17 +/- 0.05 mmol/l vs DPO-IRI 0.08 +/- 0.03 mmol/l vs EPO-IRI 0.04 +/- 0.01 mmol/l, P = 0.01). Delayed administration of DPO or EPO (T6) also significantly abrogated subsequent renal dysfunction (serum creatinine for IRI 0.17 +/- 0.05 mmol/l vs DPO-IRI 0.06 +/- 0.01 mmol/l vs EPO-IRI 0.03 +/- 0.03 mmol/l, P = 0.01). There was also significantly decreased tissue injury (apoptosis, P < 0.05), decreased proapoptotic Bax, and increased regenerative capacity, especially in the outer stripe of the outer medulla, with DPO or EPO at T0 or T6. These results reaffirm the potential clinical application of DPO and EPO as novel renoprotective agents for patients at risk of ischemic acute renal failure or after having sustained an ischemic renal insult.

  11. Effect of pre-ischaemic conditioning on hypoxic depolarization of dopamine efflux in the rat caudate brain slice measured in real-time with fast cyclic voltammetry.

    PubMed

    Davidson, Colin; Coomber, Ben; Gibson, Claire L; Young, Andrew M J

    2011-10-01

    Fast cyclic voltammetry can be used to measure dopamine release after oxygen and glucose deprivation (OGD) induced anoxic depolarization in vitro. Here we measure dopamine efflux with 1s time resolution, which is appropriate to measure OGD-evoked dopamine efflux accurately. In the present study, we examined whether OGD-evoked dopamine efflux could be used to show pre-ischaemic conditioning in the rat caudate brain slice. Caudate slices were exposed to 0, 2, or 10 min OGD pre-ischaemic conditioning, then 60 min later exposed to a second OGD event of 15 min duration. We measured the OGD-evoked dopamine efflux using fast cyclic voltammetry and in some experiments caudate dopamine and DOPAC tissue levels were measured using HPLC and 20 μm cryostat sections were Nissl stained to indicate neuronal loss. We found that 10 but not 2 min OGD pre-ischaemic conditioning resulted in a longer time to onset of OGD-evoked dopamine efflux on the main OGD event (475 ± 31 and 287 ± 30 s for 10 Vs 0 min pre-ischaemic conditioning respectively). Further, 10 min OGD pre-ischaemic conditioning resulted in less dopamine efflux on the second OGD event (4.23 ± 1.12 and 8.14 ± 0.82 μM for 10 Vs 0 min pre-ischaemic conditioning respectively), despite these slices having similar tissue dopamine content and DOPAC/DA ratio, and the rate of dopamine release was slower in the main OGD event (21 ± 5 and 74 ± 8 nM/s for 10 Vs 0 min pre-ischaemic conditioning respectively). These data suggest that 10 min OGD pre-ischaemic conditioning can evoke tolerance to a second OGD event and that voltammetric recording of OGD-evoked dopamine efflux is a useful model of pre-ischaemic conditioning in neuronal tissue.

  12. Administration of recombinant erythropoietin alone does not improve the phenotype in iron refractory iron deficiency anemia patients.

    PubMed

    Lehmberg, Kai; Grosse, Regine; Muckenthaler, Martina U; Altamura, Sandro; Nielsen, Peter; Schmid, Hansjörg; Graubner, Ulrike; Oyen, Florian; Zeller, Wolfgang; Schneppenheim, Reinhard; Janka, Gritta E

    2013-03-01

    Mutations in transmembrane protease, serine 6 (TMPRSS6) cause iron refractory iron deficiency anemia (IRIDA). Parenteral iron administration may slightly improve hemoglobin level but is troublesome for patients. Optimal treatment has yet to be determined. We identified five patients from four independent families displaying the IRIDA picture with truncating biallelic mutations in TMPRSS6, one of which is novel. Liver iron determined by superconducting quantum interference device biosusceptometry ranged from 390 to 720 µg Fe/g wet weight (normal range 100-500; n = 3). Intestinal iron absorption (12 and 32 %, normal range 10-50; n = 2) and 59Fe erythrocyte incorporation after ingestion of 59Fe (57 and 38 %, normal range 70-90; n = 2) were inadequately low for iron-deficient anemic individuals. Baseline serum erythropoietin was elevated or borderline high in four patients. Administration of recombinant human erythropoietin (rhEPO) at up to 273 and 188 U/kg body weight/week alone did not improve anemia or result in a decrease of urinary hepcidin in two individuals. In conclusion, the ability of exogenous rhEPO to increase hemoglobin level appears to be impaired in IRIDA.

  13. Can local Erythropoietin administration enhance bone regeneration in osteonecrosis of femoral head?

    PubMed

    Bakhshi, Hooman; Rasouli, Mohammad R; Parvizi, Javad

    2012-08-01

    Osteonecrosis of femoral head (ONFH) is a challenging disease. Regardless of underlying causes, the ultimate result in all cases is disruption of femoral head blood supply. Once the disease starts, it is progressive in 80% of cases. Since the majority of the affected individuals are young, every effort should be focused on preserving the patients own femoral head. These years, the role of angiogenic growth factors has been investigated with promising results in animal models of ONFH. Erythropoietin (EPO) is a well known hormone that has been used in treatment of chronic anemia for many years with few side effects. Considering the angiogenic properties of EPO, we hypothesize that local delivery of recombinant human EPO during core decompression will enhance bone regeneration in ONFH. In this way we also can avoid systemic side effects of EPO.

  14. Accidental ten times overdose administration of recombinant human erythropoietin (rh-EPO) up to 318,000 units a day in acute myocardial infarction: report of two cases.

    PubMed

    Shin, Dae-Hee; Kwon, Young-Il; Choi, Sung-Il; Park, Ui-Soon; Lee, Je; Shin, Jin-Ho; Lee, Jae-Ung; Kim, Soon-Gil; Kim, Jeong-Hyun; Lim, Heon-Kil; Lee, Bang-Hun; Kim, Kyung-Soo

    2006-02-01

    The cytokine erythropoietin protects the heart from ischaemic injury, in part by preventing apoptosis. But appropriate dose of erythropoietin for the protection of injured heart has not been studied. While we were researching the cardiac protective effects of erythropoietin in acute myocardial infarction, we experienced two cases of accidental nearly ten times overdose administration of erythropoietin up to 318,000 units instead of 33,000 units on the second day of three scheduled days of treatment. So a total of 384,000 units of erythropoietin were administered during three days. In case 1, the ALT level soared up to 386 U/l on the second day of administration and decreased slowly. It was back to normal state 3 months later. The AST level increased slowly up to 391 U/l and normalized 3 months later. Haemoglobin level was elevated up to 15.7 g/dl (14.7 g/dl at admission) and, 3 months later, normalized to 14.8 g/dl. In case 2, the ALT level was elevated up to 98 U/l on the second day of administration and decreased slowly. Three months later, the ALT level was normalized. The AST level also increased slowly up to 71 U/l and normalized 3 months later. Haemoglobin level was elevated up to 15.6 g/dl (13.8 g/dl at admission) and, 3 months later, normalized to 13.6 g/dl. In these two cases reported, these patients, even after massive overdose, tolerated it relatively well and the only side-effects we found were elevated liver enzyme and haemoglobin levels.

  15. Short-term intra-nasal erythropoietin administration with low sialic acid content is without toxicity or erythropoietic effects.

    PubMed

    Lagarto, Alicia; Bueno, Viviana; Sanchez, Jose A; Couret, Micaela; Valdes, Odalys; Barzaga, Pedro; Lopez, Raisell; Guerra, Isbel; Gabilondo, Tatiana; Vega, Yamile; Beausoleil, Irene

    2012-11-01

    The objective of this investigation was to assess the toxicological potential of nasal formulation of erythropoietin with low sialic acid content (Neuro EPO) after 28 days of intra-nasal dosing in rats besides to evaluate the immunogenicity and erythropoietic effect of the test substance. Healthy Wistar rats of both sexes were used for 28 days subacute toxicity and immunogenicity assays. Doses evaluated were 3450, 4830 and 6900 UI/kg/day. The toxicological endpoints examined included animal body weight, food consumption, hematological and biochemical patterns, antibodies determination, selected tissue weights and histopathological examination. Reversibility of toxic effects was evaluated at high dose 14 days after treatment period. Female B6D2F1 mice were used for evaluated erythropoietic effect of the nasal formulation. Hematological endpoints were examined every week during 28 days of intra-nasal dosing of 6900 UI/kg/day. Variations of hematological patterns were not observed after 28 days of intranasal dosing. A slight increase in glucose level of treated animals within the normal range was observed. This effect was not dose related and was reversible. Antibody formation was not observed in any of the test doses. Histopathological examination of organs and tissues did not reveal treatment induced changes. The administration of Neuro EPO in normocythaemic mice did not produce erythropoietic effect. These results suggest that Neuro EPO could be used as a neuroprotective agent, without significant systemic haematological side effects.

  16. Erythropoietin Derived by Chemical Synthesis

    PubMed Central

    Shieh, Jae-Hung; Peguero, Elizabeth; Hendrickson, Ronald; Moore, Malcolm A. S.; Danishefsky, Samuel J.

    2014-01-01

    Erythropoietin is a signaling glycoprotein that controls the fundamental process of erythropoiesis, orchestrating the production and maintenance of red blood cells. As administrated clinically, erythropoietin has a polypeptide backbone with complex dishomogeneity in its carbohydrate domains. Here we describe the total synthesis of homogeneous erythropoietin with consensus carbohydrate domains incorporated at all of the native glycosylation sites. The oligosaccharide sectors were built by total synthesis and attached stereospecifically to peptidyl fragments of the wild-type primary sequence, themselves obtained by solid-phase peptide synthesis. The glycopeptidyl constructs were joined by chemical ligation, followed by metal-free dethiylation, and subsequently folded. This homogeneous erythropoietin glycosylated at the three wild-type aspartates with N-linked high-mannose sialic acid–containing oligosaccharides and O-linked glycophorin exhibits Procrit-level in vivo activity in mice. PMID:24337294

  17. Delayed Administration of Pyroglutamate Helix B Surface Peptide (pHBSP), a Novel Nonerythropoietic Analog of Erythropoietin, Attenuates Acute Kidney Injury

    PubMed Central

    Patel, Nimesh S A; Kerr-Peterson, Hannah L; Brines, Michael; Collino, Massimo; Rogazzo, Mara; Fantozzi, Roberto; Wood, Elizabeth G; Johnson, Florence L; Yaqoob, Muhammad M; Cerami, Anthony; Thiemermann, Christoph

    2012-01-01

    In preclinical studies, erythropoietin (EPO) reduces ischemia-reperfusion–associated tissue injury (for example, stroke, myocardial infarction, acute kidney injury, hemorrhagic shock and liver ischemia). It has been proposed that the erythropoietic effects of EPO are mediated by the classic EPO receptor homodimer, whereas the tissue-protective effects are mediated by a hetero-complex between the EPO receptor monomer and the β-common receptor (termed “tissue-protective receptor”). Here, we investigate the effects of a novel, selective-ligand of the tissue-protective receptor (pyroglutamate helix B surface peptide [pHBSP]) in a rodent model of acute kidney injury/dysfunction. Administration of pHBSP (10 μg/kg intraperitoneally [i.p.] 6 h into reperfusion) or EPO (1,000 IU/kg i.p. 4 h into reperfusion) to rats subjected to 30 min ischemia and 48 h reperfusion resulted in significant attenuation of renal and tubular dysfunction. Both pHBSP and EPO enhanced the phosphorylation of Akt (activation) and glycogen synthase kinase 3β (inhibition) in the rat kidney after ischemia-reperfusion, resulting in prevention of the activation of nuclear factor-κB (reduction in nuclear translocation of p65). Interestingly, the phosphorylation of endothelial nitric oxide synthase was enhanced by EPO and, to a much lesser extent, by pHBSP, suggesting that the signaling pathways activated by EPO and pHBSP may not be identical. PMID:22415011

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

    SciTech Connect

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

    2008-05-01

    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.

  19. The pre-ischaemic neuroprotective effects of N1-dansyl-spermine in a transient focal cerebral ischaemia model in mice.

    PubMed

    Li, Jun; Henman, Martin C; Tatlisumak, Turgut; Shaw, Graham G; Doyle, Karen M

    2005-09-07

    The pre-ischaemic neuroprotective potential of a novel polyamine/NMDA antagonist N1-dansyl-spermine (1-5 mg kg(-1)) was studied in a transient focal cerebral ischaemia model in mice in comparison to a reference compound, MK-801 (1 or 3 mg kg(-1)). The intraluminal suture transient middle cerebral artery occlusion (MCAO) model was used. N1-dansyl-spermine and MK-801 were administered (i.p.) 30 min prior to ischaemia. A range of histological and behavioural assessments was employed. N1-dansyl-spermine had a comparable effect to MK-801 at reducing the percentage hemisphere lesion volume (%HLV) at the doses tested. Furthermore, N1-dansyl-spermine reduced the ischaemic brain oedema, which MK-801 did not. N1-dansyl-spermine significantly reversed the decrease of locomotor activity (LMA) caused by the MCAO and showed a significant effect at improving the rotarod performance impaired by MCAO. In contrast, MK-801 had no beneficial effect on sensorimotor function and even worsened the LMA. These results clearly demonstrate the pre-ischaemic neuroprotective effect of N1-dansyl-spermine in a transient focal cerebral ischaemia model.

  20. 21 CFR 864.7250 - Erythropoietin assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 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...

  1. 21 CFR 864.7250 - Erythropoietin assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 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...

  2. 21 CFR 864.7250 - Erythropoietin assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 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...

  3. Testing for recombinant erythropoietin.

    PubMed

    Delanghe, Joris R; Bollen, Mathieu; Beullens, Monique

    2008-03-01

    Erythropoietin (Epo) is a glycoprotein hormone that promotes the production of red blood cells. Recombinant human Epo (rhEpo) is illicitly used to improve performance in endurance sports. Doping in sports is discouraged by the screening of athletes for rhEpo. Both direct tests (indicating the presence of exogeneous Epo isoforms) and indirect tests (indicating hematological changes induced by exogenous Epo administration) can be used for Epo detection. At present, the test adopted by the World Anti Doping Agency is based on a combination of isoelectric focusing and double immunoblotting, and distinguishes between endogenous and rhEpo. However, the adopted monoclonal anti-Epo antibodies are not monospecific. Therefore, the test can occasionally lead to the false-positive detection of rhEpo (epoetin-beta) in post-exercise, protein-rich urine, or in case of contamination of the sample with microorganisms. An improved preanalytical care may counteract a lot of these problems. Adaptation of the criteria may be helpful to further refine direct Epo testing. Indirect tests have the disadvantage that they require blood instead of urine samples, but they can be applied to detect a broader range of performance improving techniques which are illicitly used in sports.

  4. Anemia treatment with erythropoietin in pregnant renal recipients.

    PubMed

    Cyganek, A; Pietrzak, B; Kociszewska-Najman, B; Sanko-Resmer, J; Paczek, L; Wielgos, M

    2011-10-01

    Pregnancies in renal transplant patients are considered to be high risk. Anemia is one of the major complications of pregnancy occurring among 65% to 85% of cases in this setting, especially since these patients carry additional risk factors. Herein we have presented five renal transplant recipients who were women who were treated with human recombinant erythropoietin due to severe anemia that developed during pregnancy. Hemoglobin levels below 9 g/dL after 3 weeks of oral iron administration were assumed to be qualifying criteria for erythropoietin treatment. No complication was observed to be associated with the treatment. Two of the five patients required blood transfusions despite erythropoietin administration. Two cases delivered small for gestational fetus age. Erythropoietin therapy in pregnant kidney transplant recipients should be considered to be a safe method to reduce the need for blood transfusions.

  5. Sex-Related Difference in Nitric Oxide Metabolites Levels after Nephroprotectant Supplementation Administration against Cisplatin-Induced Nephrotoxicity in Wistar Rat Model: The Role of Vitamin E, Erythropoietin, or N-Acetylcysteine.

    PubMed

    Nematbakhsh, Mehdi; Pezeshki, Zahra

    2013-01-01

    Background. Nitric oxide (NO) concentration in serum is altered by cisplatin (CP), and NO influences CP-induced nephrotoxicity. The effect of nephroprotectant agent supplementation (vitamin E, human recombinant erythropoietin (EPO), or n-acetylcysteine (NAC)) on the NO metabolites levels after CP administration in the two genders was determined. Methods. Sixty-four adult Wistar rats were randomly divided into 10 groups. Male and female rats in different groups received vehicle (saline), CP (7 mg/kg) alone, CP plus EPO (100 IU/kg), CP plus vitamin E (250 mg/kg), and CP plus NAC (600 mg/kg). CP was administrated as a single dose, but the supplementations were given for a period of 7 days. Results. In male rats, the serum levels of total NO metabolites (NO x ) and nitrite were increased significantly (P < 0.05) by CP. However, vitamin E significantly reduced the serum levels of these metabolites, which was increased by administration of CP (P < 0.05), and such findings were not observed for female rats. The EPO or NAC did not influence NO metabolites neither in male rats nor in female rats. Conclusion. Although vitamin E, EPO, and NAC are reported to be nephroprotectant agents against CP-induced nephrotoxicity, only vitamin E could reduce the level of all NO metabolites only in male rats.

  6. Erythropoietin and Nonhematopoietic Effects.

    PubMed

    Nekoui, Alireza; Blaise, Gilbert

    2017-01-01

    Erythropoietin (EPO) is the main regulator of red blood cell production. Since the 1990s, EPO has been used for the treatment of anemia associated with end-stage renal failure and chemotherapy. The erythropoietin receptors were found on other organs such as the brain, spinal cord, heart and skin. In addition, it has been shown that many tissues produce and locally release EPO in response to hypoxic, biochemical and physical stress. In cellular, animal and clinical studies, EPO protects tissues from ischemia and reperfusion injury, has antiapoptotic effects and improves regeneration after injury. In this article, we mainly review the nonhematopoietic effects and new possible clinical indications for EPO.

  7. Erythropoietin is Neuroprotective in a Transgenic Mouse Model of Multiple System Atrophy

    PubMed Central

    Pallua, Anton; Stefanova, Nadia; Poewe, Werner; Wenning, Gregor K.

    2016-01-01

    Multiple system atrophy is a rapidly progressive neurodegenerative disorder with a markedly reduced life expectancy. Failure of symptomatic treatment raises an urgent need for disease-modifying strategies. We have investigated the neuroprotective potential of erythropoietin in (proteolipid protein)-α-synuclein transgenic mice exposed to 3-nitropropionic acid featuring multiple system atrophy-like pathology including oligodendroglial α-synuclein inclusions and selective neuronal degeneration. Mice were treated with erythropoietin starting before (early erythropoietin) and after (late erythropoietin) intoxication with 3-nitropropionic acid. Nonintoxicated animals receiving erythropoietin and intoxicated animals treated with saline served as control groups. Behavioral tests included pole test, open field activity, and motor behavior scale. Immunohistochemistry for tyrosine hydroxylase and dopamine and cyclic adenosine monophosphate-regulated phosphoprotein (DARPP-32) was analyzed stereologically. Animals receiving erythropoietin before and after 3-nitropropionic acid intoxication scored significantly lower on the motor behavior scale and they performed better in the pole test than controls with no significant difference between early and late erythropoietin administration. Similarly, rearing scores were worse in 3-nitropropionic acid-treated animals with no difference between the erythropoietin subgroups. Immunohistochemistry revealed significant attenuation of 3-nitropropionic acid-induced loss of tyrosine hydroxylase and DARPP-32 positive neurons in substantia nigra pars compacta and striatum, respectively, in both erythropoietin-treated groups without significant group difference in the substantia nigra. However, at striatal level, a significant difference between early and late erythropoietin administration was observed. In the combined (proteolipid protein)-α-synuclein 3-nitropropionic acid multiple system atrophy mouse model, erythropoietin appears to rescue

  8. Erythropoietin and oxidative stress.

    PubMed

    Maiese, Kenneth; Chong, Zhao Zhong; Hou, Jinling; Shang, Yan Chen

    2008-05-01

    Unmitigated oxidative stress can lead to diminished cellular longevity, accelerated aging, and accumulated toxic effects for an organism. Current investigations further suggest the significant disadvantages that can occur with cellular oxidative stress that can lead to clinical disability in a number of disorders, such as myocardial infarction, dementia, stroke, and diabetes. New therapeutic strategies are therefore sought that can be directed toward ameliorating the toxic effects of oxidative stress. Here we discuss the exciting potential of the growth factor and cytokine erythropoietin for the treatment of diseases such as cardiac ischemia, vascular injury, neurodegeneration, and diabetes through the modulation of cellular oxidative stress. Erythropoietin controls a variety of signal transduction pathways during oxidative stress that can involve Janus-tyrosine kinase 2, protein kinase B, signal transducer and activator of transcription pathways, Wnt proteins, mammalian forkhead transcription factors, caspases, and nuclear factor kappaB. Yet, the biological effects of erythropoietin may not always be beneficial and may be poor tolerated in a number of clinical scenarios, necessitating further basic and clinical investigations that emphasize the elucidation of the signal transduction pathways controlled by erythropoietin to direct both successful and safe clinical care.

  9. Human recombinant erythropoietin in the prevention and treatment of anemia of prematurity.

    PubMed

    Ohls, Robin K

    2002-01-01

    Human recombinant erythropoietin has been studied extensively as treatment for a variety of anemias. Since in vitro studies showed the primary etiology of the anemia of prematurity to be insufficient serum erythropoietin concentrations, clinical trials have evaluated the administration of human recombinant erythropoietin to preterm infants to treat this indication. These studies were followed by pharmacokinetic determinations in animal models and preterm infants, which revealed that preterm infants required greater doses of human recombinant erythropoietin because of a more rapid clearance and greater volume of distribution. Recent studies have focused on the administration of human recombinant erythropoietin in the first weeks of life to alleviate the anemia caused by excessive phlebotomy losses, and to prevent the anemia of prematurity. In addition, human recombinant erythropoietin has been tried clinically in a variety of neonatal populations in an attempt to decrease or eliminate transfusions. Although much information has been accumulated about the clinical use of human recombinant erythropoietin in preterm infants over the last 15 years, many questions remain unanswered. The evolution of clinical practice in the care of extremely low birthweight infants continues to affect the number of transfusions. It is likely that human recombinant erythropoietin administration in combination with instituting rigorous transfusion guidelines and decreasing phlebotomy losses will have the greatest impact in decreasing transfusion requirements in all preterm and term neonates, regardless of the etiology of their anemia.

  10. Erythropoietin and Neonatal Neuroprotection

    PubMed Central

    Juul, Sandra E.; Pet, Gillian C.

    2015-01-01

    Certain groups of neonates are at high risk of developing long-term neurodevelopmental impairment (NDI) and might be considered candidates for neuroprotective interventions. This chapter will explore some of these high-risk groups, relevant mechanisms of brain injury, and specific mechanisms of cellular injury and death. The potential of erythropoietin (Epo) to act as a neuroprotective agent for neonatal brain injury will be discussed. Clinical trials of Epo neuroprotection in preterm and term infants are updated. PMID:26250911

  11. Erythropoietin binding protein from mammalian serum

    DOEpatents

    Clemons, G.K.

    1997-04-29

    Purified mammalian erythropoietin binding-protein is disclosed, and its isolation, identification, characterization, purification, and immunoassay are described. The erythropoietin binding protein can be used for regulation of erythropoiesis by regulating levels and half-life of erythropoietin. A diagnostic kit for determination of level of erythropoietin binding protein is also described. 11 figs.

  12. Erythropoietin binding protein from mammalian serum

    DOEpatents

    Clemons, Gisela K.

    1997-01-01

    Purified mammalian erythropoietin binding-protein is disclosed, and its isolation, identification, characterization, purification, and immunoassay are described. The erythropoietin binding protein can be used for regulation of erythropoiesis by regulating levels and half-life of erythropoietin. A diagnostic kit for determination of level of erythropoietin binding protein is also described.

  13. Neuroprotective Effect of Erythropoietin in Postoperation Cervical Spinal Cord Injury: Case Report and Review

    PubMed Central

    Nekoui, Alireza; Del Carmen Escalante Tresierra, Violeta; Abdolmohammadi, Sadegh; Shedid, Daniel; Blaise, Gilbert

    2015-01-01

    Introduction: New research shows shown that erythropoietin has neuro-protective effects. In preclinical trial and human clinical trials, it was demonstrated that erythropoietin is effective treatment for spinal cord injury. Early administration of medications after injury increases the hope of attenuating secondary damage and maximizing an improved outcome. Case presentation: A 42-year-old female patient presented with gait instability and progressive weakness in her right leg over a 6-year period. She was diagnosed as myelomalacia and was candidate for cervical discectomy. After surgery, she suffered from right hemiplegia due to spinal cord injury that did not respond well to routine treatment. Darbepoetin alpha (Aranesp) 100 mcg, subcutaneous daily for three days, was added to the patient’s treatment seven days after trauma and resulted in rapid improvement. The patient recovered progressively and was discharged from the hospital ten days after erythropoietin therapy. Conclusions: This case report supports the beneficial role of erythropoietin in function, maintenance, and recovery of neurons. Erythropoietin is a double-edge sword, as long-term erythropoietin therapy has some complications, like thromboembolism and stroke. Recent studies suggested that erythropoietin should be given as single high dose to exert a rapid neuro-protective effect with minimal hematopoietic side effects. We believe that the effects and other adverse consequences of erythropoietin and its non-erythropoietic derivatives should be evaluated in clinical trials. PMID:26705520

  14. [Overview of erythropoietin].

    PubMed

    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.

  15. Erythropoietin and blood doping

    PubMed Central

    Robinson, N; Giraud, S; Saudan, C; Baume, N; Avois, L; Mangin, P; Saugy, M

    2006-01-01

    Objective and method To outline the direct and indirect approaches in the fight against blood doping in sports, the different strategies that have been used and are currently being used to fight efficiently against blood doping are presented and discussed. Results and conclusions The paper outlines the different approaches and diagnostic tools that some federations have to identify and target sportspeople demonstrating abnormal blood profiles. Originally blood tests were introduced for medical reasons and for limiting misuse of recombinant human erythropoietin (rHuEPO). In this way it became possible to prevent athletes with haematocrit levels well above normal, and potentially dangerous for their health, competing in sport. Today, with nearly a decade of blood testing experience, sports authorities should be familiar with some of the limitations and specially the ability of blood tests performed prior to competitions to fight efficiently against the misuse of rHuEPO, blood transfusion, and artificial haemoglobin. PMID:16799100

  16. Erythropoietin Neuroprotection in Neonatal Cardiac Surgery: A Phase I/II Safety and Efficacy Trial

    PubMed Central

    Andropoulos, Dean B.; Brady, Ken; Easley, R. Blaine; Dickerson, Heather A.; Voigt, Robert G.; Shekerdemian, Lara S.; Meador, Marcie R.; Eisenman, Carol A.; Hunter, Jill V.; Turcich, Marie; Rivera, Carlos; McKenzie, E. Dean; Heinle, Jeffrey S.; Fraser, Charles D.

    2012-01-01

    Objectives Neonates undergoing complex congenital heart surgery have a significant incidence of neurological problems. Erythropoietin has anti-apoptotic, anti-excitatory, and anti-inflammatory properties to prevent neuronal cell death in animal models, and improves neurodevelopmental outcomes in full term neonates with hypoxic ischemic encephalopathy. We designed a prospective phase I/II trial of erythropoietin neuroprotection in neonatal cardiac surgery to assess safety, and indicate efficacy. Methods Neonates undergoing surgery for D-transposition of the great vessels, hypoplastic left heart syndrome, or aortic arch reconstruction were randomized to 3 perioperative doses of erythropoietin, or placebo. Neurodevelopmental testing with Bayley Scales of Infant and Toddler Development III was performed at age 12 months. Results 59 patients received study drug. Safety profile, including MRI brain injury, clinical events, and death, was not different between groups. 3 patients in each group died. 42 patients (22 erythropoietin, 20 placebo, 79% of survivors) returned for 12-month follow-up. The mean Cognitive Scores were erythropoietin, 101.1 ± 13.6, placebo, 106.3 ± 10.8 (p=0.19); Language Scores were erythropoietin 88.5 ± 12.8, placebo 92.4 ± 12.4 (p=0.33); and Motor Scores were erythropoietin 89.9 ± 12.3, placebo 92.6 ± 14.1, (p=0.51). Conclusions Safety profile for erythropoietin administration was not different than placebo. Neurodevelopmental outcomes were not different between groups, however this pilot study was not powered to definitively address this outcome. Lessons learned from the current study suggest optimized study design features for a larger prospective trial to definitively address the utility of erythropoietin for neuroprotection in this population. PMID:23102686

  17. Erythropoietin and diabetes mellitus.

    PubMed

    Maiese, Kenneth

    2015-10-25

    Erythropoietin (EPO) is a 30.4 kDa growth factor and cytokine that governs cell proliferation, immune modulation, metabolic homeostasis, vascular function, and cytoprotection. EPO is under investigation for the treatment of variety of diseases, but appears especially suited for the treatment of disorders of metabolism that include diabetes mellitus (DM). DM and the complications of this disease impact a significant portion of the global population leading to disability and death with currently limited therapeutic options. In addition to its utility for the treatment of anemia, EPO can improve cardiac function, reduce fatigue, and improve cognition in patients with DM as well as regulate cellular energy metabolism, obesity, tissue repair and regeneration, apoptosis, and autophagy in experimental models of DM. Yet, EPO can have adverse effects that involve the vasculature system and unchecked cellular proliferation. Critical to the cytoprotective capacity and the potential for a positive clinical outcome with EPO are the control of signal transduction pathways that include protein kinase B, the mechanistic target of rapamycin, Wnt signaling, mammalian forkhead transcription factors of the O class, silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae), and AMP activated protein kinase. Therapeutic strategies that can specifically target and control EPO and its signaling pathways hold great promise for the development of new and effective clinical treatments for DM and the complications of this disorder.

  18. Erythropoietin and diabetes mellitus

    PubMed Central

    Maiese, Kenneth

    2015-01-01

    Erythropoietin (EPO) is a 30.4 kDa growth factor and cytokine that governs cell proliferation, immune modulation, metabolic homeostasis, vascular function, and cytoprotection. EPO is under investigation for the treatment of variety of diseases, but appears especially suited for the treatment of disorders of metabolism that include diabetes mellitus (DM). DM and the complications of this disease impact a significant portion of the global population leading to disability and death with currently limited therapeutic options. In addition to its utility for the treatment of anemia, EPO can improve cardiac function, reduce fatigue, and improve cognition in patients with DM as well as regulate cellular energy metabolism, obesity, tissue repair and regeneration, apoptosis, and autophagy in experimental models of DM. Yet, EPO can have adverse effects that involve the vasculature system and unchecked cellular proliferation. Critical to the cytoprotective capacity and the potential for a positive clinical outcome with EPO are the control of signal transduction pathways that include protein kinase B, the mechanistic target of rapamycin, Wnt signaling, mammalian forkhead transcription factors of the O class, silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae), and AMP activated protein kinase. Therapeutic strategies that can specifically target and control EPO and its signaling pathways hold great promise for the development of new and effective clinical treatments for DM and the complications of this disorder. PMID:26516410

  19. Erythropoietin in Stroke Therapy: Friend or Foe

    PubMed Central

    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. PMID:25620101

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

    PubMed Central

    Sharma, Kumkum; Sharma, Sumit B.; Pukhta, Imran A.; Sharma, Amit B.; Salaria, Abdul Q.

    2013-01-01

    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 5th 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. PMID:23559764

  1. Biology of erythropoietin.

    PubMed

    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.

  2. Maximizing the erythropoietin response: iron strategies.

    PubMed

    Prabhu, Mayoor V; Nayak, Aditi; Sridhar, G; Subhramanyam, S V; Nayak, K S

    2012-01-01

    Anemia is a significant cause of morbidity and lowers the quality of life of patients suffering from chronic kidney disease (CKD). Iron deficiency is the most important cause of erythropoietin (EPO) hyporesponsiveness in CKD. EPO administration significantly increases the costs of CKD management. It follows that paramount importance must be given to enhancing responsiveness to EPO thereby ensuring that the patient derives maximum benefit. Intravenous iron (IVI) administration has been used for decades to replenish body iron stores. Multiple preparations of Iron are available in the market. However, IVI administration is fraught with dangers like adverse drug reactions, susceptibility to infection, and, as recently postulated, direct cellular toxicity. Traditional approaches to IVI administration have focused on multiple administrations of lower doses for fear of adverse reactions. However, recent studies have demonstrated that higher doses can be safely administered in a single infusion, thereby reducing hospitalization costs and patient inconvenience. Newer preparations of IVI are relatively safer, easier to administer and efficacious. Preparations like Iron sucrose, ferumoxytol, ferric carboxymaltose and iron isomaltoside do not require test doses and allow higher doses to be administered at a time with cost and effect benefits.

  3. Human CD133+ Renal Progenitor Cells Induce Erythropoietin Production and Limit Fibrosis After Acute Tubular Injury

    PubMed Central

    Aggarwal, Shikhar; Grange, Cristina; Iampietro, Corinne; Camussi, Giovanni; Bussolati, Benedetta

    2016-01-01

    Persistent alterations of the renal tissue due to maladaptive repair characterize the outcome of acute kidney injury (AKI), despite a clinical recovery. Acute damage may also limit the renal production of erythropoietin, with impairment of the hemopoietic response to ischemia and possible lack of its reno-protective action. We aimed to evaluate the effect of a cell therapy using human CD133+ renal progenitor cells on maladaptive repair and fibrosis following AKI in a model of glycerol-induced rhabdomyolysis. In parallel, we evaluated the effect of CD133+ cells on erythropoietin production. Administration of CD133+ cells promoted the restoration of the renal tissue, limiting the presence of markers of injury and pro-inflammatory molecules. In addition, it promoted angiogenesis and protected against fibrosis up to day 60. No effect of dermal fibroblasts was observed. Treatment with CD133+ cells, but not with PBS or fibroblasts, limited anemia and increased erythropoietin levels both in renal tissue and in circulation. Finally, CD133+ cells contributed to the local production of erythropoietin, as observed by detection of circulating human erythropoietin. CD133+ cells appear therefore an effective source for cell repair, able to restore renal functions, including erythropoietin release, and to limit long term maldifferentiation and fibrosis. PMID:27853265

  4. Novel applications of recombinant erythropoietin.

    PubMed

    Sharples, Edward J; Thiemermann, Christoph; Yaqoob, Magdi M

    2006-04-01

    Recombinant erythropoietin (EPO) was introduced into clinical practice after the identification of EPO as the major haemopoietic growth factor determining survival and maturation of erythroid precursors. Advances in our understanding of the novel sites of action of EPO in the vasculature, brain, heart and kidney have opened new avenues of therapeutic potential for EPO, and have led to an increased understanding of the biological roles of EPO and its mechanisms of cell protection.

  5. Cytoprotective doses of erythropoietin or carbamylated erythropoietin have markedly different procoagulant and vasoactive activities

    PubMed Central

    Coleman, Thomas R.; Westenfelder, Christof; Tögel, Florian E.; Yang, Ying; Hu, Zhuma; Swenson, LeAnne; Leuvenink, Henri G. D.; Ploeg, Rutger J.; d’Uscio, Livius V.; Katusic, Zvonimir S.; Ghezzi, Pietro; Zanetti, Adriana; Kaushansky, Kenneth; Fox, Norma E.; Cerami, Anthony; Brines, Michael

    2006-01-01

    Recombinant human erythropoietin (rhEPO) is receiving increasing attention as a potential therapy for prevention of injury and restoration of function in nonhematopoietic tissues. However, the minimum effective dose required to mimic and augment these normal paracrine functions of erythropoietin (EPO) in some organs (e.g., the brain) is higher than for treatment of anemia. Notably, a dose-dependent risk of adverse effects has been associated with rhEPO administration, especially in high-risk groups, including polycythemia–hyperviscosity syndrome, hypertension, and vascular thrombosis. Of note, several clinical trials employing relatively high dosages of rhEPO in oncology patients were recently halted after an increase in mortality and morbidity, primarily because of thrombotic events. We recently identified a heteromeric EPO receptor complex that mediates tissue protection and is distinct from the homodimeric receptor responsible for the support of erythropoiesis. Moreover, we developed receptor-selective ligands that provide tools to assess which receptor isoform mediates which biological consequence of rhEPO therapy. Here, we demonstrate that rhEPO administration in the rat increases systemic blood pressure, reduces regional renal blood flow, and increases platelet counts and procoagulant activities. In contrast, carbamylated rhEPO, a heteromeric receptor-specific ligand that is fully tissue protective, increases renal blood flow, promotes sodium excretion, reduces injury-induced elevation in procoagulant activity, and does not effect platelet production. These preclinical findings suggest that nonerythropoietic tissue-protective ligands, which appear to elicit fewer adverse effects, may be especially useful in clinical settings for tissue protection. PMID:16585502

  6. Recombinant erythropoietin in clinical practice

    PubMed Central

    Ng, T; Marx, G; Littlewood, T; Macdougall, I

    2003-01-01

    The introduction of recombinant human erythropoietin (RHuEPO) has revolutionised the treatment of patients with anaemia of chronic renal disease. Clinical studies have demonstrated that RHuEPO is also useful in various non-uraemic conditions including haematological and oncological disorders, prematurity, HIV infection, and perioperative therapies. Besides highlighting both the historical and functional aspects of RHuEPO, this review discusses the applications of RHuEPO in clinical practice and the potential problems of RHuEPO treatment. PMID:12897214

  7. Erythropoietin and iron.

    PubMed

    Kaltwasser, J P; Gottschalk, R

    1999-03-01

    Serum ferritin concentration is most informative in estimating the amount of storage iron available for a particular individual. The serum transferrin receptor concentration, in contrast to serum ferritin, provides direct information about any deficit in the adequacy of iron supply to the erythropoiesis. The combination of serum transferrin receptor and serum ferritin provides complete information about storage and functional iron compartments. Using this combination along with the hemoglobin concentration, it is possible to define the iron nutritional status completely. Inflammatory conditions as well as parenteral iron administration interfere, however, with the direct and quantitative ferritin to storage iron relationship and, therefore, have to be considered carefully with respect to diagnostic purposes. The diagnostic use of the serum transferrin receptor is presently limited because of limitations in methodology and definition (standardization) of reference ranges.

  8. Erythropoietin Neuroprotection with Traumatic Brain Injury

    PubMed Central

    Ponce, Lucido L.; Navarro, Jovany Cruz; Ahmed, Osama; Robertson, Claudia S.

    2012-01-01

    Numerous experimental studies in recent years have suggested that erythropoietin (EPO) is an endogenous mediator of neuroprotection in various central nervous system disorders, including TBI. Many characteristics of EPO neuroprotection that have been defined in TBI experimental models suggest that it is an attractive candidate for a new treatment of TBI. EPO targets multiple mechanisms known to cause secondary injury after TBI, including anti-excitotoxic, antioxidant, anti-edematous, and anti-inflammatory mechanisms. EPO crosses the blood brain barrier. EPO has a known dose response and time window for neuroprotection and neurorestoration that would be practical in the clinical setting. However, EPO also stimulates erythropoiesis, which can result in thromboembolic complications. Derivatives of EPO which do not bind to the classical EPO receptor (carbamylated EPO) or that have such a brief half-life in the circulation that they do not stimulate erythropoiesis (asialo EPO and neuro EPO) have the neuroprotective activities of EPO without these potential thromboembolic adverse effects associated with EPO administration. Likewise, a peptide based on the structure of the Helix B segment of the EPO molecule that does not bind to the EPO receptor (pyruglutamate Helix B surface peptide) has promise as another alternative to EPO that may provide neuroprotection without stimulating erythropoiesis. PMID:22421507

  9. Downstream modulation of extrinsic apoptotic pathway in streptozotocin-induced Alzheimer's dementia in rats: Erythropoietin versus curcumin.

    PubMed

    Samy, Doaa M; Ismail, Cherine A; Nassra, Rasha A; Zeitoun, Teshreen M; Nomair, Azhar M

    2016-01-05

    Erythropoietin and curcumin showed promising neuroprotective effects in various models of Alzheimer's dementia. This study was designed to compare the beneficial effects of erythropoietin and/or curcumin in intracerebro-ventricular (ICV) streptozotocin-induced Alzheimer's like disease in rats. Rats received ICV injection of either saline (control, n=8 rats), or streptozotocin. Three weeks following surgery, streptozotocin-injected rats were assigned into 4 groups (8 rats each); vehicle, curcumin (80mg/kg/day, orally), erythropoietin (500 IU/kg every other day, intraperitoneally) and combined (curcumin and erythropoietin)-treated groups. After 3 months of treatment, rats were subjected to neurobehavioral testing, and then killed for biochemical and histological assessment of hippocampus. Fas ligand protein and caspase-8 activity as mediators of extrinsic apoptotic pathway, oxidative stress markers (malondialdehyde and reduced glutathione) and β-amyloid (1-40 and 1-42) peptides were measured. The results showed that administration of erythropoietin suppressed extrinsic apoptosis better than curcumin, while curcumin was more effective in combating oxidative stress in ICV-streptozotocin injected rats. Both erythropoietin and curcumin treatments (individually or combined) equally reduced the hippocampal β-amyloid accumulation and improved cognitive impairment in Morris water maze and passive avoidance tasks. The combined treatment was the most effective in ameliorating apoptosis and oxidative stress rather than behavioral responses or β-amyloid burden. In conclusion, ICV-streptozotocin-induced Alzheimer's dementia activates hippocampal Fas ligand-mediated apoptosis, which could be reduced by erythropoietin and/or curcumin treatment. Curcumin supplementation alone could ameliorate cognitive deficits and reverse biochemical alterations in ICV-streptozotocin Alzheimer's rat model without the hazardous polycythemic effect of long-term erythropoietin injection.

  10. [The role of erythropoietin in improvement of wound healing].

    PubMed

    Sorg, H; Kuhbier, J W; Menger, B; Reimers, K; Harder, Y; Vogt, P M

    2010-11-01

    Pleiotropic substances are characterized by their versatile and complex range of actions which makes them potential new active agents for the therapy of wounds. Besides its known effect to increase red blood cell production, the glycoprotein hormone erythropoietin (EPO) has been found to demonstrate a tissue protective effect in several other organs. The administration of EPO during skin wound healing is most likely essentially based on its cytopotective, proangiogenic, antiapoptotic and antiinflammatory effects. Herein EPO stimulates a coordinated interaction of different types of cells at a low or only a single dose. This review article aims to present the advantages and disadvantages of EPO administration in different experimental models to study the healing and regeneration processes of the skin and discusses possible clinical applications.

  11. Specific activities of poetam preparation (superlow-doses of antibodies to erythropoietin) and recombinant erythropoietin.

    PubMed

    Dygai, A M; Zhdanov, V V; Udut, E V; Simanina, E V; Gur'yantseva, L A; Khrichkova, T Yu; Epshtein, O I; Sergeeva, S A

    2006-09-01

    We compared the capacity of superlow-dose of antibodies to erythropoietin (Poetam) and recombinant erythropoietin (Recormon) to stimulate the recovery of adriamycin-suppressed erythropoiesis in mice. Both preparations exhibited high erythron activation capacity and considerably increased the content of erythrocytes and reticulocytes in the peripheral blood and content of erythrokaryocytes and erythroid precursors in the hemopoietic tissue of experimental animals. The effect of Recormon manifested immediately after injection, while the effect of Poetam was somewhat delayed, but more lasting (due to activation of host erythropoietin system).

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

    PubMed

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

    2009-01-30

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

  13. Outcomes with the Use of Recombinant Human Erythropoietin in Critically Ill Burn Patients

    DTIC Science & Technology

    2010-09-01

    human erythropoietin (rhEPO) has been approved by the U.S. Food and Drug Administration for use in anemic patient with chronic kidney disease ( CKD ).7...January 1, 2007 to December 31, 2008). Patients treated with rhEPO who also had any other indication for erythropoiesis before BICU to in- clude CKD ...17 In addition, mechanisms that lead to benefit in anemic patient with CKD may be at play in AK1. 18 Whether there may be a mortality benefit

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

    PubMed Central

    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

  15. Pure red cell aplasia due to antibody against erythropoietin in hemodialysis patients

    PubMed Central

    Rahbar, Maryam; Chitsazian, Zahra; Abdoli, Firoozeh; Moeini Taba, Seyed-Masoud; Akbari, Hosein

    2017-01-01

    Background Anemia is a common complication of chronic renal failure due to reduce erythropoietin production by kidneys. Anemia treated with recombinant human erythropoietin (rHu-EPO). Pure red cell aplasia (PRCA) due to antibody productionagainst rHu-EPO is a rare but major complication of this drug. Objectives The aim of this study was to determine the prevalence of PRCA due to antibodies in dialysis patients with resistant anemia who received erythropoietin. Patients and Methods We studied 128 under maintenance hemodialysis patients more than 3 month in Kashan. In patients with anemia who received erythropoietin with dose requirements based on weight and anemia and without any another cause for anemia, evaluate for PRCA and anti-rHu-EPO antibody level were measured by ELISA. Results In this research, 75 patients (58.6%) were male and 53 patients (41.4%) were female. The mean age of the patients was 59.05 ± 16.66 years. The result of analysis showed that 55 (43%) patients had anemia with hemoglobin level less than 10 mg/dL. Only 3 patients had PRCA and antibodies against erythropoietin in serum. There were no correlation between age, gender, cause of renal failure, hemodialysis duration, hemoglobin level, rHu-EPO dose and levels of anti-rHu-EPO antibody serum value. Conclusions The result of this study indicated that administration of rHu-EPO in dialysis patients afflicted to kidney failure may cause PRCA especially through intravenous injection. However, this change is not statistically significant. PMID:28042550

  16. 21 CFR 864.7250 - Erythropoietin assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... erythropoietin (an enzyme that regulates the production of red blood cells) in serum or urine. This assay provides diagnostic information for the evaluation of erythrocytosis (increased total red cell mass) and anemia. (b) Classification. Class II. The special control for this device is FDA's “Document for...

  17. Development of a new radioimmunoassay for erythropoietin using recombinant erythropoietin

    SciTech Connect

    Mason-Garcia, M.; Beckman, B.S.; Brookins, J.W.; Powell, J.S.; Lanham, W.; Blaisdell, S.; Keay, L.; Li, S.C.; Fisher, J.W. )

    1990-11-01

    The development of a 24 hour radioimmunoassay for erythropoietin (EPO) using EPO derived from recombinant DNA as both immunogen and ligand is described in the present paper. Mixed breed rabbits immunized with 10 micrograms/kg of EPO derived from a stably transfected cell line (MD) produced antibodies to EPO with high titer (up to 1:896,000 final dilution in the tube), high affinity (8.4 x 10(11) liter/M), and good specificity. Purified EPO from the above source or from AmGen Biologicals (AG) were successfully radioiodinated with the chloramine-T method and used as ligand in the radioimmunoassay. Standard dose-response curves prepared with EPO from both commercial sources were not significantly different and showed a sensitivity of 0.75 to 0.96 mU/tube. The dose-response curves in both systems also showed parallelism with serially diluted serum from a patient with aplastic anemia. Within-assay and between-assay precision were determined by assaying multiple replicates of a serum pool. Recovery of exogenous EPO added to a serum pool averaged 97% for both systems. The range of normal human serum EPO was determined by assaying the sera of 153 hematologically-normal adult subjects and was found to be 1.1 to 27.3 mU/ml for MD EPO and 0.5 to 16.7 mU/ml for AG EPO. Sera from several patients with hematologic abnormalities were also assayed, including those of 36 patients with anemia of end-stage renal disease (mean +/- SEM, 29.5 +/- 4.0 mU/ml; P less than 0.01). In conclusion, this new, more rapid and sensitive radioimmunoassay system can be used to measure EPO levels in sera from normal human subjects and patients with several types of anemia, and should also be very useful in therapeutic drug monitoring of patients receiving EPO from various commercial sources.

  18. A quest for erythropoietin over nine decades.

    PubMed

    Fisher, J W

    1998-01-01

    The major research accomplishments of the author are described from the time of his PhD thesis work on the mechanism of cobalt polycythemia to the present day. His early work on the quest for the cell that produces erythropoietin (Epo) to his current work on oxygen sensing and signal transduction pathways involved in erythropoietin gene expression are reported. He describes his main research interest in the mechanism of cobalt polycythemia between 1954 and 1962 and his research on how hormones such as the glucocorticoids function in the regulation of erythropoiesis (1956-1962). His major findings during this period were the discovery that hydrocortisone and corticosterone stimulated erythropoiesis (1958) and that cobalt increased erythropoietin production in the isolated perfused dog kidney (1961). He describes how he was led astray in some of his early studies on the cells in the kidney that produce erythropoietin, because of the less-developed technology available to him at that time; and how in situ hybridization and other molecular biology techniques enabled him to confirm some of the earlier work in mice by other investigators that interstitial cells in the kidney were the site of production of erythropoietin in the primate. His work in the controversial area of the mechanism of the anemia of end-stage renal disease is described in detail, as it pertains to Epo deficiency and suppressed erythroid progenitor cell response to Epo. He also discusses his recent work on signal transduction pathways (hypoxia, nitric oxide, adenosine, and C kinase) in oxygen sensing and Epo gene expression.

  19. Polycythemia in transgenic mice expressing the human erythropoietin gene

    SciTech Connect

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

    1989-04-01

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

  20. What evidence supports use of erythropoietin as a novel neurotherapeutic?

    PubMed

    Brines, Michael

    2002-09-01

    In its hormonal role, erythropoietin is produced by the kidney in response to hypoxic stress and signals the bone marrow to increase the number of circulating erythrocytes. It has become clear in recentyears, however, that erythropoietin and its receptor are members of a cytokine superfamily that mediates diverse functions in nonhematopoietic tissues. Nonhormonal erythropoietin actions include a critical role in the development, maintenance, protection, and repair of the central nervous system (CNS). Our group has found serendipitously that recombinant human erythropoietin administered into the systemic circulation is not strictly excluded from the brain. Human recombinant erythropoietin appears within the cerebrospinal fluid in neuroprotective concentrations, probably by translocation initiated by binding to the erythropoietin receptor on the luminal surface of the endothelium. This observation suggested that recombinant human erythropoietin could be therapeutic for CNS diseases, a possibility further supported by positive findings in a model of ischemic stroke. Recombinant human erythropoietin administered systemically either in advance of, or up to 3 hours after, a cerebral arterial occlusion in rats prevents apoptosis of neurons within the ischemic penumbra and reduces infarction volume by 75%. Erythropoietin also dramatically reduces postinfarct inflammation in this model. Other brain and spinal cord injuries such as mechanical trauma, experimental autoimmune encephalitis or subarachnoid hemorrhage also respond favorably to erythropoietin administered within a similar window of time. In addition to ameliorating neuronal injury, erythropoietic therapy also directly modulates neuronal excitability and acts as a trophic factor for neurons in vivo and in vitro. Erythropoietin may therefore provide benefit in epileptic or degenerative neurologic diseases. Given the outstanding safety record for recombinant human erythropoietin after more than a decade in widespread

  1. Long-term results of enriched environment and erythropoietin after hypobaric hypoxia in rats.

    PubMed

    Hralová, M; Angerová, Y; Gueye, T; Bortelová, J; Svestková, O; Zima, T; Lippertová-Grünerová, M

    2013-01-01

    After global cerebral hypoxia, many patients are severely disabled even after intensive neurorehabilitation. Secondary mechanisms of brain injury as a result of biochemical and physiological events occur within a period of hours to months, and provide a window of opportunity for therapeutic intervention. Erythropoietin (EPO) has been shown to be neuroprotective in the brain subjected to a variety of injuries. Fifty-nine 3-month-old male Wistar rats were randomly distributed to experimental groups with respect to the housing (enriched environment - EE, standard housing - SH), to hypoxia exposure, and to EPO treatment. An acute mountain sickness model was used as a hypobaric hypoxia simulating an altitude of 8000 m. One half of the animals received erythropoietin injections, while the others were injected saline. Spatial memory was tested in a Morris water maze (MWM). The escape latency and the path length were measured. Better spatial learning in MWM was only seen in the group that received erythropoietin together with enriched environment. EPO administration itself had no influence on spatial memory. The results were very similar for both latencies and path lengths. These results support the idea that after brain injuries, the recovery can be potentiated by EPO administration combined with neurorehabilitation.

  2. Impact of an Interleukin-1 Receptor Antagonist and Erythropoietin on Experimental Myocardial Ischemia/Reperfusion Injury

    PubMed Central

    Grothusen, Christina; Hagemann, Angelika; Attmann, Tim; Braesen, Jan; Broch, Ole; Cremer, Jochen; Schoettler, Jan

    2012-01-01

    Background. Revascularization of infarcted myocardium results in release of inflammatory cytokines mediating myocardial reperfusion injury and heart failure. Blockage of inflammatory pathways dampens myocardial injury and reduces infarct size. We compared the impact of the interleukin-1 receptor antagonist Anakinra and erythropoietin on myocardial ischemia/reperfusion injury. In contrast to others, we hypothesized that drug administration prior to reperfusion reduces myocardial damage. Methods and Results. 12–15 week-old Lewis rats were subjected to myocardial ischemia by a 1 hr occlusion of the left anterior descending coronary artery. After 15 min of ischemia, a single shot of Anakinra (2 mg/kg body weight (bw)) or erythropoietin (5000 IE/kg bw) was administered intravenously. In contrast to erythropoietin, Anakinra decreased infarct size (P < 0.05, N = 4/group) and troponin T levels (P < 0.05, N = 4/group). Conclusion. One-time intravenous administration of Anakinra prior to myocardial reperfusion reduces infarct size in experimental ischemia/reperfusion injury. Thus, Anakinra may represent a treatment option in myocardial infarction prior to revascularization. PMID:22649318

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

    PubMed

    Aachmann-Andersen, Niels Jacob; Just Christensen, Søren; Lisbjerg, Kristian; Oturai, Peter; Meinild-Lundby, Anne-Kristine; Holstein-Rathlou, Niels-Henrik; Lundby, Carsten; Vidiendal Olsen, Niels

    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 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.

  4. Resistance of dialyzed patients to erythropoietin

    PubMed Central

    Alves, Michelle Teodoro; Vilaça, Sandra Simone; Carvalho, Maria das Graças; Fernandes, Ana Paula; Dusse, Luci Maria Sant’Ana; Gomes, Karina Braga

    2015-01-01

    Resistance to recombinant human erythropoietin is a common condition in dialyzed patients with chronic kidney disease and is associated with more hospitalizations, increased mortality and frequent blood transfusions. The main cause of hyporesponsiveness to recombinant human erythropoietin in these patients is iron deficiency. However, a high proportion of patients does not respond to treatment, even to the use of intravenous iron, which indicates the presence of other important causes of resistance. In addition to the iron deficiency, the most common causes of resistance include inflammation, infection, malnutrition, inadequate dialysis, and hyperparathyroidism, although other factors may be associated. In the presence of adequate iron stores, other causes should be investigated and treated appropriately. PMID:26041422

  5. Effect of plethora on erythropoietin levels

    SciTech Connect

    Moccia, G.; Miller, M.E.; Garcia, J.F.; Cronkite, E.P.

    1980-01-01

    The mechanism by which plethora suppresses erythropoiesis in experimental animals has been assumed to be related to a decrease in erythropoietin (Ep) levels. Prior to the advent of a radioimmunoassay (RIA) for Ep this theory could not be confirmed because of the insensitivity of the bioassay for Ep. In the present study hypertransfusion induced plethora was associated with approximately a 50% reduction in plasma Ep levels in CF/sub 1/ mice.

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

    PubMed

    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 <10 g/l). After rEPO treatment of beta-thalassemia 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.

  7. Regenerative medicine: does Erythropoietin have a role?

    PubMed

    Buemi, Michele; Lacquaniti, Antonio; Maricchiolo, Giulia; Bolignano, Davide; Campo, Susanna; Cernaro, Valeria; Sturiale, Alessio; Grasso, Giovanni; Buemi, Antoine; Allegra, Alessandro; Donato, Valentina; Genovese, Lucrezia

    2009-01-01

    Regenerative Medicine, a recent new medical domain, aims to develop new therapies through the stimulation of natural regenerative processes also in human beings. In this field, Erythropoietin (EPO) represents a significant subject of research. Several studies allow the assertion that EPO, in different concentrations, has protective effects mainly on the central nervous system, cardiovascular system and renal tissue. This action is carried out through one of few regenerative activities of human beings: angiogenesis. This mechanism, which involves endothelial stem cells and VEGF (Vascular Endothelial Growth Factor), has been experimentally demonstrated with Recombinant human erythropoietin (rHuEPO) and Darbepoetin, a long-acting EPO derivate. Furthermore, the demonstration of a cardiac production of EPO in Fugu rubripes and in Zebrafish has led cardiologists to "discover" Erythropoietin, postulating a hypothetical role in treatment of cardiovascular disease for this hormone. This is some of the experimental evidence which demonstrates that EPO can be in reason considered an important element of research of Regenerative Medicine and put in the network of drugs able to regenerate tissues and organs.

  8. Procedures for monitoring recombinant erythropoietin and analogs in doping.

    PubMed

    Lamon, Séverine; Robinson, Neil; Saugy, Martial

    2010-03-01

    Hemoglobin concentration is one of the principal factors of aerobic power and, consequently, of performance in many types of physical activities. The use of recombinant human erythropoietin is, therefore, particularly powerful for improving the physical performances of patients, and, more generally, improving their quality of life. This article discusses procedures for monitoring recombinant erythropoietin and its analogues in doping for athletic performance.

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

    PubMed Central

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

    2014-01-01

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

  10. State-of-the-art biosimilar erythropoietins in the management of renal anemia: lessons learned from Europe and implications for US nephrologists.

    PubMed

    Covic, Adrian; Abraham, Ivo

    2015-09-01

    The European Medicines Agency (EMA), under a strictly regulated pathway, has approved several biosimilar products since 2005, including biosimilar versions of the erythropoiesis-stimulating agent (ESA) epoetin alfa since 2007. Subsequent to these approvals, the use of biosimilar epoetin alfa in the management of renal anemia has grown steadily throughout Europe. With the enactment of the US Biologics Price Competition and Innovation Act of 2009, a US Food and Drug Administration regulatory approval process for biosimilars was legalized. Thus, biosimilar erythropoietin products are expected to be available for prescription in the USA by mid-decade, presumably at a price that is competitive with the originator brand-name reference products. In this paper, we describe the status of originator and biosimilar ESAs, review the clinical development and regulatory approval of biosimilar erythropoietins in Europe, and summarize relevant efficacy and safety information of biosimilar erythropoietins in relation to their reference products to provide a background for US nephrologists as they appraise biosimilar erythropoietins as treatment options for renal anemia. Key lessons learned from Europe are that (a) EMA-approved biosimilar erythropoietins have comparable efficacy and safety profiles to their reference product erythropoietin; (b) pharmacovigilance preapproval and postapproval are critical, especially with regard to immunogenicity and vascular thromboembolic events; (c) strict preapproval and postapproval requirements must guide the regulatory pathway for biosimilars; and (d) high-quality manufacturing and production processes must be established to ensure quality biosimilar products. The availability of biosimilar erythropoietins in the USA will provide nephrologists with alternative effective, and potentially more affordable, treatment options for patients with renal anemia.

  11. Erythropoietin-induced iritis-like reaction.

    PubMed

    Beiran, I; Krasnitz, I; Mezer, E; Meyer, E; Miller, B

    1996-01-01

    The present report describes an iritis-like reaction found in 13 patients treated with recombinant human erythropoietin (Eprex), a drug given to hemodialysis patients for their chronic anemia. Among 120 patients being treated by hemodialysis in two centers affiliated with our medical center, ten out of 30 Eprex-treated patients but none of 90 not being treated with Eprex developed this reaction. The observations described support a causal relation between Eprex treatment and the iritis-like reaction. Further investigative effort is needed to establish the mechanism.

  12. Erythropoietin protects cardiac myocytes against anthracycline-induced apoptosis

    SciTech Connect

    Fu Ping; Arcasoy, Murat O. . E-mail: arcas001@mc.duke.edu

    2007-03-09

    The cardiotoxic adverse effects of anthracycline antibiotics limit their therapeutic utility as essential components of chemotherapy regimens for hematologic and solid malignancies. Here we show that the hematopoietic cytokine erythropoietin attenuates doxorubicin-induced apoptosis of primary neonatal rat ventricular cardiomyocytes in a dose-dependent manner. Erythropoietin treatment induced rapid, time-dependent phosphorylation of MAP kinases (MAPK) Erk1/2 and the phosphatidylinositol 3-kinase substrate Akt. Treatment of cardiomyocytes with inhibitors of phosphatidylinositol 3-kinase (LY294002) or Akt (Akti-1/2) abolished the protective effect of erythropoietin, whereas treatment with MAPK kinase (MEK1) inhibitor U0126 did not. Erythropoietin also induced the phosphorylation of GSK-3{beta}, a downstream target of PI3K-Akt. Because phosphorylation is known to inactivate GSK-3{beta}, we investigated whether GSK-3{beta} inhibition is cardioprotective. We found that GSK-3{beta} inhibitors SB216763 or lithium chloride blocked doxorubicin-induced cardiomyocyte apoptosis in a manner similar to erythropoietin, suggesting that GSK-3{beta} inhibition is involved in erythropoietin-mediated cardioprotection. Erythropoietin may serve as a novel cardioprotective agent against anthracycline-induced cardiotoxicity.

  13. Erythropoietin as a novel brain and kidney protective agent.

    PubMed

    Moore, E M; Bellomo, R; Nichol, A D

    2011-05-01

    Erythropoietin is a 30.4 kDa glycoprotein produced by the kidney, which is mostly known for its physiological function in regulating red blood cell production in the bone marrow Accumulating evidence, however suggests that erythropoietin has additional organ protective effects, which may specifically be useful in protecting the brain and kidneys from injury. Experimental evidence suggests that these protective mechanisms are multi-factorial in nature and may include inhibition of apoptotic cell death, stimulation of cellular regeneration, inhibition of deleterious pathways and promotion of recovery. In this article we review the physiology of erythropoietin, assess previous work that supports the role of erythropoietin as a general tissue protective agent and explain the mechanisms by which it may achieve this tissue protective effect. We then focus on specific laboratory and clinical data that suggest that erythropoietin has a strong brain protective and kidney protective effect. In addition, we comment on the implications of these studies for clinicians at the bedside and for researchers designing controlled trials to further elucidate the true clinical utility of erythropoietin as a neuroprotective and nephroprotective agent. Finally, we describe EPO-TBI, a double-blinded multi-centre randomised controlled trial involving the authors that is being conducted to investigate the organ protective effects of erythropoietin on the brain, and also assesses its effect on the kidneys.

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

    PubMed Central

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

    2016-01-01

    During the past decade, accumulating evidence from both clinical and experimental studies has indicated that erythropoietin may have antidepressant effects. In addition to the kidney and liver, many organs have been identified as secretory tissues for erythropoietin, including the brain. Its receptor is expressed in cerebral and spinal cord neurons, the hypothalamus, hippocampus, neocortex, dorsal root ganglia, nerve axons, and Schwann cells. These findings may highlight new functions for erythropoietin, which was originally considered to play a crucial role in the progress of erythroid differentiation. Erythropoietin and its receptor signaling through JAK2 activate multiple downstream signaling pathways including STAT5, PI3K/Akt, NF-κB, and MAPK. These factors may play an important role in inflammation and neuroprogression in the nervous system. This is particularly true for the hippocampus, which is possibly related to learning, memory, neurocognitive deficits and mood alterations. Thus, the influence of erythropoietin on the downstream pathways known to be involved in the treatment of depression makes the erythropoietin-related pathway an attractive target for the development of new therapeutic approaches. Focusing on erythropoietin may help us understand the pathogenic mechanisms of depression and the molecular basis of its treatment. PMID:27164096

  15. Pharmacokinetics and pharmacodynamics of recombinant human erythropoietin in athletes. Blood sampling and doping control

    PubMed Central

    SOUILLARD, AGNES; AUDRAN, MICHEL; BRESSOLLE, FRANÇOISE; GAREAU, RAYNALD; DUVALLET, ALAIN; CHANAL, JEAN-LOUIS

    1996-01-01

    1The pharmacokinetics of recombinant human erythropoietin (rHuEpo) were initially determined in two healthy volunteers after a single subcutaneous dose (50 u kg−1). Twenty subjects then received repeated subcutaneous administrations of high dose (200 u kg−1) rHuEpo and 10 subjects received placebo. An immunoradiometric assay was used to measure the concentrations of erythropoietin (Epo) in serum and urine. 2Serum Epo concentration-time profiles were best described by a one-compartment open model with zero-order input. The mean elimination half-life (±s.d.) was 42.0±34.2 h. Clearance, uncorrected for bioavailability, was 0.05±0.01 l h−1 kg& minus;1. Erythropoietin concentrations returned to normal values in serum and urine, 7 and 4 days after the last administration, respectively. 3The recombinant hormone was well tolerated. Significant changes in reticulocytes and red blood cells, haemoglobin concentrations and haematocrit were observed after administration of rHuEpo. In the control group, these parameters remained unchanged. 4The change in reticulocytes was used as an index of the therapeutic effect of rHuEpo. The concentration-effect relationship was best described by an exponential model. 5These data show the limitations of the measurement of Epo concentrations in blood and urine samples, collected in athletes during competition, for antidoping control. Epo doping can be detected only during or within 4 to 7 days of ending, a course of rHuEpo. PMID:8877027

  16. Polycythemia, increased erythropoietin levels in a patient with renal lymphoma

    PubMed Central

    Bhat, Riyaz Ahmad; Khan, Imran; Khan, Irfan; Mir, Mohd Ashraf

    2014-01-01

    A young male presented to our clinic with 3 months history of shortness of breathness and progressive distension of abdomen. On investigations, patient had renal failure, polycythemia and nephromegaly. A diagnosis of non-Hodgkin's lymphoma was made on renal and lymph node biopsy. Serum erythropoietin concentrations were physiologically inappropriate. – Erythropoietin immunohistochemistry on renal tissue samples demonstrated positive staining for tumor cells. This patient was managed as a case of infiltrative lymphoproliferative disorder with kidney involvement having polycythemia owing to paraneoplastic Erythropoietin production and possibly local hypoxia produced by tumor cells. With maximum efforts, we could not find such an association in the literature. PMID:25161994

  17. Efficacy of a single, weekly dose of recombinant erythropoietin in myelodysplastic syndromes.

    PubMed

    Musto, Pellegrino; Falcone, Antonietta; Sanpaolo, Grazia; Bodenizza, Carlo; La Sala, Antonio; Perla, Gianni; Carella, Angelo Michele

    2003-07-01

    Thirteen patients with low-to-intermediate risk myelodysplastic syndrome (MDS) received recombinant erythropoietin (r-EPO) at the single, weekly dose of 40.000 U for at least 8 weeks. Five patients (38.4%) achieved a major erythroid response (increased haemoglobin levels > 2 g/dl and/or transfusion independence), which is currently maintained after 3-11 months, without modification of r-EPO dose. This study suggests that 40.000 U r-EPO given once a week may be at least as effective as the more frequent (daily or three times a week) administrations of the drug usually employed in MDS patients.

  18. Novel uses for recombinant erythropoietin therapy in unlicensed indications.

    PubMed

    Macartney, Christine A; Adgey, A A Jennifer; Jones, Frank G C; Morris, Treen C M; McMullin, Mary-Frances

    2004-01-01

    Clinical uses for recombinant human erythropoietin (rHuEPO) therapy continue to expand. Initial use was in anaemia associated with end-stage renal disease, but more recently there have been many reports of the benefits of erythropoietin in other clinical situations such as cancer-related anaemia. Recombinant erythropoietin reduces the need for blood transfusion and hence exposure to donor blood products as well as improving quality of life. We report four patients who were transfusion dependent, none of whom had licensed indications for the use of recombinant erythropoietin. Two patients had microangiopathic haemolytic anaemia secondary to mechanical valve haemolysis and were unsuitable for any further cardiac intervention. One patient had anaemia of chronic disease and anti-Vel red cell antibodies, making compatible blood transfusions difficult to obtain. The fourth patient had primary thrombocythaemia and developed transfusion-dependent anaemia secondary to myelosuppressive agents. All four patients had a relative deficiency in endogenous erythropoietin levels ranging between 7 and 41 IU/l. After commencing recombinant erythropoietin therapy, all had a response in haemoglobin of at least 1 g/dl with an overall improvement in their quality of life. We conclude that rHuEPO is a very convenient and useful form of treatment in transfusion-dependent anaemia and in some cases beyond the licensed indications.

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

    PubMed

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

    2012-01-01

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

  20. Erythropoietin in bone - Controversies and consensus.

    PubMed

    Hiram-Bab, Sahar; Neumann, Drorit; Gabet, Yankel

    2017-01-01

    Erythropoietin (Epo) is the main hormone that regulates the production of red blood cells (hematopoiesis), by stimulating their progenitors. Beyond this vital function, several emerging roles have been noted for Epo in other tissues, including neurons, heart and retina. The skeletal system is also affected by Epo, however, its actions on bone are, as yet, controversial. Here, we review the seemingly contradicting evidence regarding Epo effects on bone remodeling. We also discuss the evidence pointing to a direct versus indirect effect of Epo on the osteoblastic and osteoclastic cell lineages. The current controversy may derive from a context-dependent mode of action of Epo, namely opposite skeletal actions during bone regeneration and steady-state bone remodeling. Differences in conclusions from the published in-vitro studies may thus relate to the different experimental conditions. Taken together, these studies indicate a complexity of Epo functions in bone cells.

  1. Regeneration in the nervous system with erythropoietin.

    PubMed

    Maiese, Kenneth

    2016-01-01

    Globally, greater than 30 million individuals are afflicted with disorders of the nervous system accompanied by tens of thousands of new cases annually with limited, if any, treatment options. Erythropoietin (EPO) offers an exciting and novel therapeutic strategy to address both acute and chronic neurodegenerative disorders. EPO governs a number of critical protective and regenerative mechanisms that can impact apoptotic and autophagic programmed cell death pathways through protein kinase B (Akt), sirtuins, mammalian forkhead transcription factors, and wingless signaling. Translation of the cytoprotective pathways of EPO into clinically effective treatments for some neurodegenerative disorders has been promising, but additional work is necessary. In particular, development of new treatments with erythropoiesis-stimulating agents such as EPO brings several important challenges that involve detrimental vascular outcomes and tumorigenesis. Future work that can effectively and safely harness the complexity of the signaling pathways of EPO will be vital for the fruitful treatment of disorders of the nervous system.

  2. Erythropoietin (EPO) in acute kidney injury.

    PubMed

    Moore, Elizabeth; Bellomo, Rinaldo

    2011-03-21

    Erythropoietin (EPO) is a 30.4 kDa glycoprotein produced by the kidney, and is mostly well-known for its physiological function in regulating red blood cell production in the bone marrow. Accumulating evidence, however, suggests that EPO has additional organ protective effects, which may be useful in the prevention or treatment of acute kidney injury. These protective mechanisms are multifactorial in nature and include inhibition of apoptotic cell death, stimulation of cellular regeneration, inhibition of deleterious pathways, and promotion of recovery.In this article, we review the physiology of EPO, assess previous work that supports the role of EPO as a general tissue protective agent, and explain the mechanisms by which it may achieve this tissue protective effect. We then focus on experimental and clinical data that suggest that EPO has a kidney protective effect.

  3. Effects of erythropoietin on the bone microenvironment.

    PubMed

    McGee, S J; Havens, A M; Shiozawa, Y; Jung, Y; Taichman, R S

    2012-02-01

    It has been well established that blood and bone share a unique, regulatory relationship with one another, though the specifics of this relationship still remain unanswered. Erythropoietin (Epo) is known primarily for its role as a hematopoietic hormone. However, after the discovery of Epo receptor outside the hematopoietic tissues, Epo has been avidly studied for its possible nonhematopoietic effects. It has been proposed that Epo interacts with bone both directly, by activating bone marrow stromal cells, and indirectly, through signaling pathways on hematopoietic stem cells. Yet, the role of Epo in regulating skeletal maintenance and regeneration remains controversial. Here, we review the current state of knowledge pertaining to the effects of Epo on the skeleton.

  4. Regeneration in the nervous system with erythropoietin

    PubMed Central

    Maiese, Kenneth

    2015-01-01

    Globally, greater than 30 million individuals are afflicted with disorders of the nervous system accompanied by tens of thousands of new cases annually with limited, if any, treatment options. Erythropoietin (EPO) offers an exciting and novel therapeutic strategy to address both acute and chronic neurodegenerative disorders. EPO governs a number of critical protective and regenerative mechanisms that can impact apoptotic and autophagic programmed cell death pathways through protein kinase B (Akt), sirtuins, mammalian forkhead transcription factors, and wingless signaling. Translation of the cytoprotective pathways of EPO into clinically effective treatments for some neurodegenerative disorders has been promising, but additional work is necessary. In particular, development of new treatments with erythropoiesis-stimulating agents such as EPO brings several important challenges that involve detrimental vascular outcomes and tumorigenesis. Future work that can effectively and safely harness the complexity of the signaling pathways of EPO will be vital for the fruitful treatment of disorders of the nervous system. PMID:26549969

  5. [Treatment of renal anemia with erythropoietin].

    PubMed

    Spustova, V; Kovac, A

    1999-08-01

    During the last decade, a considerable amount of new information has accumulated regarding therapy optimalization of renal anaemia with recombinant human erythropoietin (EPO). Key question involved is EPO hyporesponsiveness caused by absolute or functional iron deficiency. Most controversial issue in the treatment of renal anaemia in patients with chronic renal insufficiency is the definition of optimal target haemoglobin. Many questions about optimizing EPO therapy were considered at the 2nd European Epoetin Symposium which was held in April 1998 on Crete. Discussion was devoted also to revision of a draft version of the European Best Practice Guidelines for the Management of Anaemia in Patients with Chronic Renal Failure. The presented review is on summary of new insights presented at the symposium. (Ref. 85.)

  6. Effect of erythropoietin on free radical oxidation and glycoprotein expression in platelets under conditions of chronic renal failure.

    PubMed

    Osikov, M V

    2014-05-01

    A short-term open prospective study examined 62 patients at the terminal stage of chronic renal failure. The experimental group received erythropoietin in a total dose of about 40,000 U. The expression of glycoproteins IIb-IIIa, IIb, and Ib was enhanced, the content of LPO products was elevated, and SOD and catalase activities were reduced in platelets from patients with chronic renal failure. Administration of erythropoietin partially restored free radical oxidation and expression of glycoproteins IIb-IIIa, IIb, and Ib in platelets. A significant correlation was revealed between the expression of platelet receptors on the one hand, and content of LPO products and SOD and catalase activities, on the other hand.

  7. Effect of recombinant erythropoietin on functional activity of cultured human cells.

    PubMed

    Emel'yanova, E A; Kosykh, A V; Sukhanov, Yu V; Vorotelyak, E A; Vasil'ev, A V

    2012-08-01

    We studied the effect of recombinant human erythropoietin on functional activity of skin cells in vitro. It was found that erythropoietin stimulated proliferation of mesenchymal and epithelial cells and effectively protected epidermal HaCaT cells from apoptosis. Insignificant effect of erythropoietin on contraction of collagen gel by mesenchymal cells was revealed. These findings suggest that erythropoietin can be a promising component of wound-healing preparations.

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

    NASA Astrophysics Data System (ADS)

    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

  9. Erythropoietin concentrations and isoforms in urine of anonymous Olympic athletes during the Nagano Olympic Games.

    PubMed

    Berglund, B; Wide, L

    2002-12-01

    The ordinary doping control urine samples of 36 anonymous participants (cross-country skiers, biathlon athletes, and curling athletes) of the 1998 Nagano Olympic Games were analyzed for erythropoietin and erythropoietin isoforms. The urine erythropoietin concentration (IU/l) was determined with a competitive radioimmunoassay method and the isoforms were studied by electrophoresis and given as milli albumin mobility units (mAMU). Erythropoietin was detectable in 23 out of 36 specimens (64%). The biathlon and curling athletes had similar urine concentration of erythropoietin. The group of 16 cross-country skiers had significantly (P < 0.05) increased urine concentration of erythropoietin as compared to curling athletes and four of them had urine erythropoietin concentrations between 3.6 and 5.1 IU/l. The electrophoretic mobility of erythropoietin was determined in all eight samples with urine concentration of erythropoietin of more than 2 (range 2.1-5.1) IU/l. No single urine specimen with a median erythropoietin electrophoretic mobility below the cut-off level of 670 mAMU (indicative of doping with recombinant erythropoietin) was registered. Erythropoietin in urine was detected in 71% and the isoforms of Epo characterized in 29% of the anonymous Olympic endurance athletes. The urine concentration of erythropoietin in the biathlon and curling athletes were similar to those of non-athletes. The group of cross-country skiers had higher levels of erythropoietin in urine. These higher levels of urine erythropoietin in cross-country skiers are partly due to more concentrated urine specimens.

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

    SciTech Connect

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

    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.

  11. Pure red cell aplasia and anti-erythropoietin antibodies in patients treated with epoetin.

    PubMed

    Casadevall, Nicole

    2003-11-01

    Recombinant human erythropoietin (epoetin) was first used for the treatment of renal anaemia in 1986. During the first 10 years of its use, epoetin-induced antibodies were a rare complication and only three cases of patients with epoetin-induced antibodies associated with pure red cell aplasia (PRCA) were published. Since 1998, however, there has been a significant increase in the number of patients developing severe anaemia during the course of epoetin treatment due to neutralizing antibodies. Patients with PRCA present with an absolute resistance to epoetin therapy and then rapidly develop severe anaemia with a very low reticulocyte count (<10 000/mm(3)). Consequently, patients become dependent on blood transfusions to maintain an acceptable level of haemoglobin. By December 2002, approximately 142 patients worldwide had been diagnosed with antibody-positive PRCA after receiving epoetin. The vast majority of these patients had been treated with the Eprex/Erypo brand of epoetin alfa, but there were also some cases in which patients had been receiving epoetin beta (NeoRecormon). To date, there have been no cases of antibody-mediated PRCA reported with the sole use of darbepoetin alfa (Aranesp). All patients with epoetin-induced anti-erythropoietin antibodies had received the drug subcutaneously (s.c.), and almost all had chronic kidney disease-related anaemia. To our knowledge, no patient treated exclusively by intravenous (i.v.) administration has developed anti-erythropoietin antibodies. The increase in reported cases coincides with the removal of human serum albumin from the ex-US formulation of epoetin alfa, in order to comply with new regulations from the European regulatory authorities. It has been proposed that the new formulation is less stable, allowing aggregates of erythropoietin molecules to form, which increases the probability of antibody formation. Treatment with epoetin must be discontinued if PRCA is suspected. Patients do not respond to an

  12. Erythropoietin's inhibiting impact on hepcidin expression occurs indirectly.

    PubMed

    Gammella, Elena; Diaz, Victor; Recalcati, Stefania; Buratti, Paolo; Samaja, Michele; Dey, Soumyadeep; Noguchi, Constance Tom; Gassmann, Max; Cairo, Gaetano

    2015-02-15

    Under conditions of accelerated erythropoiesis, elevated erythropoietin (Epo) levels are associated with inhibition of hepcidin synthesis, a response that ultimately increases iron availability to meet the enhanced iron needs of erythropoietic cells. In the search for erythroid regulators of hepcidin, many candidates have been proposed, including Epo itself. We aimed to test whether direct interaction between Epo and the liver is required to regulate hepcidin. We found that prolonged administration of high doses of Epo in mice leads to great inhibition of liver hepcidin mRNA levels, and concomitant induction of the hepcidin inhibitor erythroferrone (ERFE). Epo treatment also resulted in liver iron mobilization, mediated by increased ferroportin activity and accompanied by reduced ferritin levels and increased TfR1 expression. The same inhibitory effect was observed in mice that do not express the homodimeric Epo receptor (EpoR) in liver cells because EpoR expression is restricted to erythroid cells. Similarly, liver signaling pathways involved in hepcidin regulation were not influenced by the presence or absence of hepatic EpoR. Moreover, Epo analogs, possibly interacting with the postulated heterodimeric β common EpoR, did not affect hepcidin expression. These findings were supported by the lack of inhibition on hepcidin found in hepatoma cells exposed to various concentrations of Epo for different periods of times. Our results demonstrate that hepcidin suppression does not require the direct binding of Epo to its liver receptors and rather suggest that the role of Epo is to stimulate the synthesis of the erythroid regulator ERFE in erythroblasts, which ultimately downregulates hepcidin.

  13. Erythropoietin and erythropoietin receptor in hepatocellular carcinoma: correlation with vasculogenic mimicry and poor prognosis.

    PubMed

    Yang, Zhihong; Sun, Baocun; Zhao, Xiulan; Shao, Bing; An, Jindan; Gu, Qiang; Wang, Yong; Dong, Xueyi; Zhang, Yanhui; Qiu, Zhiqiang

    2015-01-01

    To evaluate erythropoietin (Epo) and erythropoietin receptor (EpoR) expression, its relationship with vasculogenic mimicry (VM) and its prognostic value in human hepatocellular carcinoma (HCC), we examined Epo/EpoR expression and VM formation using immunohistochemistry and CD31/PAS (periodic acid-Schiff) double staining on 92 HCC specimens. The correlation between Epo/EpoR expression and VM formation was analyzed using two-tailed Chi-square test and Spearman correlation analysis. Survival curves were generated using Kaplan-Meier method. Multivariate analysis was performed using Cox regression model to assess the prognostic values. Results showed positive correlation between Epo/EpoR expression and VM formation (P < 0.05). Patients with Epo or EpoR expression exhibited poorer overall survival (OS) than Epo-negative or EpoR-negative patients (P < 0.05). Epo-positive/VM-positive and EpoR-positive/VM-positive patients had the worst OS (P < 0.05). In multivariate survival analysis, age, Epo and EpoR were independent prognostic factors related to OS. These results will provide evidence for further research on HCC microcirculation patterns and also will provide new possible targets for HCC diagnosis and treatment.

  14. Mystery Story about Erythropoietin (Epo) and Erythropoietin Receptor (EpoR) are Disguised?

    PubMed

    Cubranić, Aleksandar; Redzovic, Arnela; Dobrila-Dintinjana, Renata; Vukelić, Jelena; Dintinjana, Marijan

    2015-05-01

    In this review we would like to focus our attention upon very controversial reports on Erythropoietin (Epo) and Erythropoietin Receptor (EpoR) expression in cancer patients. The effects of Epo on cancerous tissues are poorly understood. Hypoxia results in an increase in the level of the production of both Epo and EpoR via activation of the hypoxia-inducible factor 1 (HIF-1) pathway. HIF-1α, promotes the expression of vascular endothelial growth factor (VEGF). The signaling through VEGF in both a paracrine and an autocrine manner is required for the homeostasis of adult vessels. Macrophages stimulate vessel sprouting via a soluble factor other than VEGF, rather than through direct contact with endothelial cells. The intriguing questions are set about many researches to link Epo/EpoR expression and function in order to establish one of the mechanisms of tumor growth, disease progression of cancer patient. However, it is uncertain role in tumour angiogenesis as promoter and stimulator of tumour growth which should need to be furtherly validated.

  15. EPO's alter ego: erythropoietin has multiple actions.

    PubMed

    Lappin, Terence R; Maxwell, A Peter; Johnston, Patrick G

    2002-01-01

    Many cancer patients suffer from anemia, which has a major detrimental effect on their quality of life. Recombinant human erythropoietin (rHuEPO) is now widely used in cancer patients, as it improves hematocrit, lowers blood transfusion requirements, and improves quality of life. Recent research indicates that EPO has pleiotropic effects on the body well beyond the maintenance of red cell mass, but the mechanisms involved in relieving fatigue and improving quality of life in cancer patients are poorly understood. EPO receptors (EPO-Rs) have been detected in many different cells and tissues, providing evidence for autocrine, paracrine, and endocrine functions of EPO. Apart from its endocrine function, EPO may have a generalized role as an antiapoptotic agent that is associated with enhancement of muscle tone, mucosal status, and gonadal and cognitive function. The recent discovery of EPO-Rs in breast tumor vasculature, while raising important questions about the possible effects of pharmacological doses of rHuEPO on tumor cells, also suggests that the receptors could provide a useful target for drugs attached to EPO.

  16. Recent developments in doping testing for erythropoietin.

    PubMed

    Reichel, Christian

    2011-08-01

    The constant development of new erythropoiesis-stimulating agents (ESAs), since the first introduction of recombinant erythropoietin (rhEpo) for clinical use, has also necessitated constant development of methods for detecting the abuse of these substances. Doping with ESAs is prohibited according to the World Anti-Doping Code and its prohibited list of substances and methods. Since the first publication of a direct and urine-based detection method in 2000, which uses changes in the Epo isoform profile as detected by isoelectric focusing in polyacrylamide slab gels (IEF-PAGE), the method has been constantly adapted to the appearance of new ESAs (e.g., Dynepo, Mircera). Blood had to be introduced as an additional matrix, because Mircera (a PEGylated Epo) is best confirmed in serum or plasma after immunoaffinity purification. A Mircera ELISA was developed for fast screening of sera. With the appearance of Dynepo and copy epoetins, the additional application of sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE or equivalent) became necessary. The haematological module of the Athlete Biological Passport is the latest development in multivariable indirect testing for ESA doping. The article summarizes the main strategies currently used in Epo anti-doping testing with special focus on new developments made between 2009 and 2010.

  17. Erythropoietin Restores Long-Term Neurocognitive Function Involving Mechanisms of Neuronal Plasticity in a Model of Hyperoxia-Induced Preterm Brain Injury

    PubMed Central

    Sifringer, Marco; van de Looij, Yohan; Herz, Josephine; Sizonenko, Stéphane V.; Kempe, Karina; Palasz, Joanna; Hadamitzky, Martin; Fandrey, Joachim

    2016-01-01

    Cerebral white and grey matter injury is the leading cause of an adverse neurodevelopmental outcome in prematurely born infants. High oxygen concentrations have been shown to contribute to the pathogenesis of neonatal brain damage. Here, we focused on motor-cognitive outcome up to the adolescent and adult age in an experimental model of preterm brain injury. In search of the putative mechanisms of action we evaluated oligodendrocyte degeneration, myelination, and modulation of synaptic plasticity-related molecules. A single dose of erythropoietin (20,000 IU/kg) at the onset of hyperoxia (24 hours, 80% oxygen) in 6-day-old Wistar rats improved long-lasting neurocognitive development up to the adolescent and adult stage. Analysis of white matter structures revealed a reduction of acute oligodendrocyte degeneration. However, erythropoietin did not influence hypomyelination occurring a few days after injury or long-term microstructural white matter abnormalities detected in adult animals. Erythropoietin administration reverted hyperoxia-induced reduction of neuronal plasticity-related mRNA expression up to four months after injury. Thus, our findings highlight the importance of erythropoietin as a neuroregenerative treatment option in neonatal brain injury, leading to improved memory function in adolescent and adult rats which may be linked to increased neuronal network connectivity. PMID:27493706

  18. Effects of Erythropoietin on Electrocardiogram Changes in Carbon Monoxide Poisoning: an Experimental Study in Rats

    PubMed Central

    Asgharian Rezaee, Mitra; Moallem, Seyed Adel; Imenshahidi, Mohsen; Farzadnia, Mahdi; Mohammadpour, Amir Hooshang

    2012-01-01

    The aim of this study was to define the electrocardiogram (ECG) changes following the moderate to severe CO intoxication in rats, and also evaluating the effect of erythropoietin (EPO) on observed cardiac disturbances. The growing literature on erythropoietin effect on cardiac ischemia led us to question its effect on cardiotoxicity due to the carbon monoxide poisoning. Wistar rats were exposed to three different concentrations of CO (250 PPM, 1000 PPM or 3000 PPM). EPO was administrated (5000 IU/Kg, intraperitoneal injection) at the end of CO exposure and then the animals were re-oxygenated with ambient air. Subsequently ECG recording, heart rate and carboxyhemoglobin values were evaluated. ECG changes following the CO intoxication included ST segment elevation and depression, T wave inversion and first-degree AV block. Ischemic ECG changes reduced significantly in EPO-treated animals. In the present study, for the first time, EPO was investigated for the management of cardiac complications due to the CO poisoning. Our results showed that EPO could inhibit ischemic changes of ECG after the CO poisoning. PMID:24250553

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

    PubMed

    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.

  20. Erythropoietin alleviates hepatic insulin resistance via PPARγ-dependent AKT activation

    PubMed Central

    Ge, Zhijuan; Zhang, Pengzi; Hong, Ting; Tang, Sunyinyan; Meng, Ran; Bi, Yan; Zhu, Dalong

    2015-01-01

    Erythropoietin (EPO) has beneficial effects on glucose metabolism and insulin resistance. However, the mechanism underlying these effects has not yet been elucidated. This study aimed to investigate how EPO affects hepatic glucose metabolism. Here, we report that EPO administration promoted phosphatidylinositol 3-kinase (PI3K)/AKT pathway activation in palmitic acid (PA)-treated HepG2 cells and in the liver of high-fat diet (HFD)-fed mice, whereas adenovirus-mediated silencing of the erythropoietin receptor (EPOR) blocked EPO-induced AKT signalling in HepG2 cells. Importantly, a peroxisome proliferator-activated receptor γ (PPARγ) antagonist and PPARγ small interfering RNA (siRNA) abrogated the EPO-induced increase in p-AKT in HepG2 cells. Lentiviral vector-mediated hepatic PPARγ silencing in HFD-fed C57BL/6 mice impaired EPO-mediated increases in glucose tolerance, insulin sensitivity and hepatic AKT activation. Furthermore, EPO activated the AMP-activated protein kinase (AMPK)/sirtuin 1 (SIRT1) signalling pathway, and AMPKα and SIRT1 knockdown each attenuated the EPO-induced PPARγ expression and deacetylation and PPARγ-dependent AKT activation in HepG2 cells. In summary, these findings suggest that PPARγ is involved in EPO/EPOR-induced AKT activation, and targeting the PPARγ/AKT pathway via EPO may have therapeutic implications for hepatic insulin resistance and type 2 diabetes. PMID:26643367

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

    PubMed Central

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

    2015-01-01

    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. PMID:26189892

  2. Carbamylated Erythropoietin: A Prospective Drug Candidate for Neuroprotection

    PubMed Central

    Chen, Jianmin; Yang, Zheng; Zhang, Xiao

    2015-01-01

    Carbamylated erythropoietin (cEpo), which is neuroprotective but lacks hematopoietic activity, has been attracting rising concerns. However, the cellular and molecular mechanisms involved in the process of neuroprotection of cEpo are not well known. Based on several recent reports, the neuroprotective effects of cEpo are illustrated, and signaling pathways involved in the different effects of erythropoietin and cEpo are discussed. These newly reported researches may shed new light on the development and application of cEpo, a prospective drug candidate for neuroprotection. PMID:26862298

  3. Recombinant Human Erythropoietin Antagonizes Trastuzumab Treatment of Breast Cancer Cells via Jak2-Mediated Activation of Src and Inactivation of PTEN

    PubMed Central

    Liang, Ke; Esteva, Francisco J.; Albarracin, Constance; Stemke-Hale, Katherine; Lu, Yang; Bianchini, Giampaolo; Yang, Ching-Yi; Li, Yong; Li, Xinqun; Chen, Chun-Te; Mills, Gordon B.; Hortobagyi, Gabriel N.; Mendelsohn, John; Hung, Mien-Chie; Fan, Zhen

    2010-01-01

    SUMMARY We found that the receptor for erythropoietin (EpoR) is coexpressed with human epidermal growth factor receptor-2 (HER2) in a significant percentage of human breast tumor specimens and breast cancer cell lines. Exposure of HER2 and EpoR dual-positive breast cancer cells to recombinant human erythropoietin (rHuEPO) activated cell signaling. Concurrent treatment of the cells with rHuEPO and trastuzumab reduced the cells’ response to trastuzumab both in vitro and in vivo. We identified Jak2-mediated activation of Src and inactivation of PTEN as underlying mechanisms through which rHuEPO antagonizes trastuzumab-induced therapeutic effects. Furthermore, we found that compared with administration of trastuzumab alone, concurrent administration of rHuEPO and trastuzumab correlated with shorter progression-free and overall survival in patients with HER2-positive metastatic breast cancer. PMID:21075308

  4. The Effect of Presurgery Recombinant Erythropoietin on Post-surgery Hematocrit following Orthognathic Surgery

    PubMed Central

    Politano, Nicholas; Jaskolka, Michael; Blakey, George; Turvey, Timothy; White, Raymond; Phillips, Ceib

    2013-01-01

    Purpose Compare the post-surgery red cell mass as indicated by hematocrit value of orthognathic surgery patients given iron supplementation and a single presurgery dose of erythropoietin alpha(EPO) and patients who did not receive either EPO or iron supplementation (NEPO). Subjects and Methods Subjects who had a Lefort I osteotomy(LFI) or a combination of a LFI and bilateral sagittal split osteotomy(BSSO) between 2005 and 2008, and were at least 13 years of age, were included. Subjects were excluded if they had a history of maxillofacial trauma, a craniofacial syndrome, or a major systemic medical condition. Subjects had either the drug administered with iron supplements prior to surgery(EPO; Surgeon A protocol) or received neither (NEPO; Surgeon B protocol). Venous blood samples were taken, in accordance with clinic protocol, before surgery (before administration of EPO) and on post-surgery day 1. Multiple linear regression with backward selection was used to analyze the change in hematocrit value. Explanatory variables included group, pre-surgery hematocrit, age, gender, length of surgery, blood loss, and crystalloid (fluid replacement) volume. Results 178 eligible patients were included: 86 patients (48%) had a combination LFI and BSSO and 92 patients (52%) an isolated LFI. 114 (64%) had erythropoietin alpha/ iron supplements administered presurgery, while 64 did not. The average change in hematocrit as an indicator of the change in red cell mass was statistically significantly different(P= 0.01) for the subjects who received preoperative administration of EPO with iron supplementation compared to those who did not receive EPO+Iron. The administration of EPO + iron was protective: the decrease in hematocrit after surgery was smaller for subjects in the EPO group even after controlling for age, gender, preoperative hematocrit, length of surgery, blood loss, and crystalloid (fluid replacement ) volume. Conclusions A single presurgery dose of erythropoietin with

  5. Increased Synthesis of Liver Erythropoietin with CKD.

    PubMed

    de Seigneux, Sophie; Lundby, Anne-Kristine Meinild; Berchtold, Lena; Berg, Anders H; Saudan, Patrick; Lundby, Carsten

    2016-08-01

    Anemia of CKD seems to be related to impaired production of renal erythropoietin (Epo). The glycosylation pattern of Epo depends on the synthesizing cell and thus, can indicate its origin. We hypothesized that synthesis of Epo from nonkidney cells increases to compensate for insufficient renal Epo production during CKD. We determined plasma Epo levels and Epo glycosylation patterns in 33 patients with CKD before undergoing dialysis and nine patients with CKD undergoing dialysis. We compared these values with values obtained in healthy volunteers and other controls. Although patients with CKD before undergoing dialysis had median (interquartile range) Epo levels higher than those of healthy controls (13.8 IU/L; interquartile range, 10.0-20.7 IU/L versus 8.4 IU/L; interquartile range, 7.6-9.0 IU/L; P<0.01), these patients were moderately anemic (mean±SD; hemoglobin =118±17 g/L). Detected as the percentage of migrated isoforms (PMI), Epo glycosylation in patients with CKD before undergoing dialysis (PMI=36.1±11.7%) differed from that in healthy controls (PMI=9.2±3.8%; P<0.01) but not from that in umbilical cord plasma (PMI=53.9±10.6%; P>0.05), which contains mainly liver-derived Epo. Furthermore, glycosylation modification correlated with eGFR loss. These results suggest that patients with CKD maintain persistent Epo synthesis despite declining renal function, and this maintenance may result in part from increased liver Epo synthesis.

  6. Acute normobaric hypoxia stimulates erythropoietin release.

    PubMed

    Mackenzie, Richard W A; Watt, Peter W; Maxwell, Neil S

    2008-01-01

    Investigations studying the secretion of EPO (erythropoietin) in response to acute hypoxia have produced mixed results. Further, the errors associated with the various methods used to determine EPO are not well documented. The purpose of the current study was to determine the EPO response of 17 trained male subjects to either an acute bout of normobaric hypoxia (Hy; n = 10) or normoxia (Con; n = 7). A secondary aim was to determine the error associated with the measurement of EPO. After baseline tests, the treatment group (Hy) underwent a single bout of hypoxic exposure (F(I(O(2))) approximately 0.148; 3100 m) consisting of a 90-min rest period followed by a 30-min exercise phase (50% V(O)(2max)). Venous blood samples were drawn pre (0 min) and post (120 min) each test to assess changes in plasma EPO (DeltaEPO). The control (Con) group was subjected to the same general experimental design, but placed in a normoxic environment (F(I(O(2))) approximately 0.2093). The Hy group demonstrated a mean increase in EPO [19.3 (4.4) vs. 24.1 (5.1) mU/mL], p < 0.04, post 120 min of normobaric hypoxia. The calculated technical error of measurement for EPO was 2.1 mU/mL (9.8%). It was concluded that an acute bout of hypoxia, has the capacity to elevate plasma EPO. This study also demonstrates that the increase in EPO accumulation was 2 times greater than the calculated measurement of error.

  7. Recombinant human erythropoietin offers neuroprotection through inducing endogenous erythropoietin receptor and neuroglobin in a neonatal rat model of periventricular white matter damage.

    PubMed

    Zhu, Lihua; Huang, Li; Wen, Quan; Wang, Ting; Qiao, Lixing; Jiang, Li

    2017-03-27

    Recombinant human erythropoietin (rh-EPO) has been reported to have protective effects against brain injury. The purpose of this study was to evaluate the levels of erythropoietin receptor (EPOR) and neuroglobin (Ngb) in a neonatal rat model of periventricular white matter damage (PWMD), and to identify the relationship between the two proteins. On postnatal day 3 (P3), rats underwent permanent ligation of the right common carotid artery followed by 6% O2 for 4h (HI) or sham operation and normoxic exposure (sham). Immediately after HI, rats received a single intraperitoneal injection of rh-EPO (5U/g) or saline. We assessed the expression level of Ngb and EPOR on postnatal days 5, 7, 10 and 14. EPOR in the HI rats was initially increased as compared to the sham rats at P5. Subsequently, EPOR expression decreased, but was maintained at a higher level than in sham rats from P7 to P14. In rh-EPO treated rats, the increase in EPOR was greater than in HI rats at P5. However, EPOR levels decreased sharply from P7 to P14. In HI rats, Ngb was increased compared to the sham rats from P5 to P14. Ngb levels were further upregulated after rh-EPO administration from P5 to P10 compared to HI rats. However, this upregulation decreased at P14. In conclusion, this study shows that EPOR and Ngb were upregulated, and both of them act as important coordinated neuroprotectors in rh-EPO treatment of PWMD. However, the two proteins exhibit different expression patterns.

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

    PubMed

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

    2008-02-01

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

  9. Endogenous erythropoietin signaling facilitates skeletal muscle repair and recovery following pharmacologically induced damage

    PubMed Central

    Jia, Yi; Suzuki, Norio; Yamamoto, Masayuki; Gassmann, Max; Noguchi, Constance Tom

    2012-01-01

    Erythropoietin acts by binding to its cell surface receptor on erythroid progenitor cells to stimulate erythrocyte production. Erythropoietin receptor expression in nonhematopoietic tissue, including skeletal muscle progenitor cells, raises the possibility of a role for erythropoietin beyond erythropoiesis. Mice with erythropoietin receptor restricted to hematopoietic tissue were used to assess contributions of endogenous erythropoietin to promote skeletal myoblast proliferation and survival and wound healing in a mouse model of cardiotoxin induced muscle injury. Compared with wild-type controls, these mice had fewer skeletal muscle Pax-7+ satellite cells and myoblasts that do not proliferate in culture, were more susceptible to skeletal muscle injury and reduced maximum load tolerated by isolated muscle. In contrast, mice with chronic elevated circulating erythropoietin had more Pax-7+ satellite cells and myoblasts with increased proliferation and survival in culture, decreased muscle injury, and accelerated recovery of maximum load tolerated by isolated muscle. Skeletal muscle myoblasts also produced endogenous erythropoietin that increased at low O2. Erythropoietin promoted proliferation, survival, and wound recovery in myoblasts via the phosphoinositide 3-kinase/AKT pathway. Therefore, endogenous and exogenous erythropoietin contribute to increasing satellite cell number following muscle injury, improve myoblast proliferation and survival, and promote repair and regeneration in this mouse induced muscle injury model independent of its effect on erythrocyte production.—Jia, Y., Suzuki, N., Yamamoto, M., Gassmann, M., Noguchi, C. T. Endogenous erythropoietin signaling facilitates skeletal muscle repair and recovery following pharmacologically induced damage. PMID:22490927

  10. [Use of human recombinant erythropoietin in children with cancer].

    PubMed

    Guyot, D; Margueritte, G

    2005-09-01

    Eighty percent of children with cancer suffer from anemia at the time of diagnosis. The physiopathology of anemia is complex. Although anemia can be life threatening, its consequences on the physical, psychological and social state of the child are often minimized. Blood transfusion is the main treatment of anemia: its efficacy is immediate but shortlasting, and it involves infectious and hemolytic risks. The human recombinant erythropoietin has been used for more than 25-years, and is often prescribed to adults with cancer and anemia. The human recombinant erythropoietin rHuEPO is nowadays used when blood transfusion is contra-indicated because of religious or cultural considerations, although several promising studies have been conducted about rHuEPO and children with cancer since 1996: it might be soon the preferential alternative treatment to anemia in children with cancer.

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

    PubMed Central

    Pichon, Aurélien; Jeton, Florine; El Hasnaoui-Saadani, Raja; Hagström, Luciana; Launay, Thierry; Beaudry, Michèle; Marchant, Dominique; Quidu, Patricia; Macarlupu, Jose-Luis; Favret, Fabrice; Richalet, Jean-Paul; Voituron, Nicolas

    2016-01-01

    Despite its well-known role in red blood cell production, it is now accepted that erythropoietin (Epo) has other physiological functions. Epo and its receptors are expressed in many tissues, such as the brain and heart. The presence of Epo/Epo receptors in these organs suggests other roles than those usually assigned to this protein. Thus, the aim of this review is to describe the effects of Epo deficiency on adaptation to normoxic and hypoxic environments and to suggest a key role of Epo on main physiological adaptive functions. Our original model of Epo-deficient (Epo-TAgh) mice allowed us to improve our knowledge of the possible role of Epo in O2 homeostasis. The use of anemic transgenic mice revealed Epo as a crucial component of adaptation to hypoxia. Epo-TAgh mice survive well in hypoxic conditions despite low hematocrit. Furthermore, Epo plays a key role in neural control of ventilatory acclimatization and response to hypoxia, in deformability of red blood cells, in cerebral and cardiac angiogenesis, and in neuro- and cardioprotection. PMID:27800506

  12. Erythropoietin reduces cumulative nephrotoxicity from cisplatin and enhances renal tubular cell proliferation.

    PubMed

    Zafirov, Dimce; Petrusevska, G; Sikole, Aleksandar; Trojacanec, J; Labacevski, N; Kostova, E; Jakovski, K; Atanasovska, E; Petrov, S

    2008-12-01

    Cisplatin, a heavy metal complex, is one of the most active drugs used in the treatment of several human malignancies. However, high-dose therapy with cisplatin is limited by its cumulative nephrotoxicity. The main objectives of this study were to determine the role of recombinant human erythropoietin (Epoetin alfa) in the prevention of nephrotoxicity induced experimentally in Wistar rats by long-term administration of cisplatin (2 mg/kg/b.w./week) over eight weeks, and an evaluation of its effect on renal tubular cell proliferation. The animals were randomly assigned into three groups, each including 25 rats. Group 1 (CP) received only cisplatin (2 mg/kg/b.w./week), group 2 (CP+EPO) received cisplatin (2 mg/kg/b.w./week) and epoetin alfa (150 IE/kg/b.w./three times a week), and group 3 (control group) received only saline. During the study, the following tests for the assessment of the renal function and renal damages were performed: determination of concentration of serum creatinine and BUN and determination of total protein quantity in 24-hour urine samples. At the end of the study, the abdomen was opened and both kidneys of the rats were removed and sent for histological and morphometric analysis. Ki-67 was used as a tool to determine a proliferative index. The results obtained have shown that epoetin alfa significantly reduced the functional renal failures and renal damages, and increased toleration of high doses of cisplatin. At the same time, our results with regard to tubular proliferative index have confirmed that one of the possible mechanisms by which erythropoietin accomplishes its renoprotective effect is stimulation of tubular cell proliferation and regeneration.

  13. Recombinant erythropoietin differently affects proliferation of mesothelioma cells but not sensitivity to cisplatin and pemetrexed.

    PubMed

    Palumbo, Camilla; Battisti, Sonia; Carbone, Daniela; Albonici, Loredana; Alimandi, Maurizio; Bei, Roberto; Modesti, Andrea

    2008-04-01

    The combination of cisplatin and pemetrexed represents the newly established standard of care for patients with unresectable malignant mesothelioma (MM). However, this chemotherapy regimen appears to be associated with an increased prevalence of higher grade anemia as compared to treatment with cisplatin alone. Human recombinant erythropoietin (rHuEpo) is currently used for the treatment of anemia in cancer patients. Still, following the finding that the erythropoietin receptor (EpoR) is expressed by several tumor cells types and after the trials reporting that the recombinant cytokine can adversely affect tumor progression and patient survival, the clinical safety of rHuEpo administration to neoplastic patients has recently been questioned. The observation that the expression of EpoR, variably associated with the expression of the cognate ligand, is a common feature of MM cells prompted us to investigate whether treatment with rHuEpo could elicit proliferative and cytoprotective signals in EpoR-positive MM cell lines. Biochemical responsiveness of MM cells to rHuEpo was demonstrated by the time-course activation of both ERK1/2 and AKT following treatment with the recombinant cytokine. A moderately increased mitogenic activity was observed in two out of five MM cell lines treated with pharmacologically relevant concentrations of rHuEpo. On the other hand, the recombinant cytokine, administered either before or after cisplatin and pemetrexed, failed to interfere with the cytotoxic effects exerted by the chemotherapeutic drugs on the five MM cell lines. According to the presented findings, rHuEpo appears to have an overall limited impact on cell growth and no effect on MM sensitivity to chemotherapy.

  14. Association of Serum Erythropoietin with Cardiovascular Events, Kidney Function Decline and Mortality: The Health ABC Study

    PubMed Central

    Garimella, Pranav S.; Katz, Ronit; Patel, Kushang V.; Kritchevsky, Stephen B.; Parikh, Chirag R.; Ix, Joachim H.; Fried, Linda F.; Newman, Anne B.; Shlipak, Michael G.; Harris, Tamara B.; Sarnak, Mark J.

    2015-01-01

    Background Studies suggest that in patients with heart failure (HF), high serum erythropoietin is associated with risk of recurrent HF and mortality. Trials of erythropoietin stimulating agents in persons with kidney disease have also suggested an increased incidence of adverse clinical events. No studies have evaluated the association of endogenous erythropoietin levels with clinical outcomes in the community living older adults. Methods and Results Erythropoietin concentration was measured in 2,488 participants aged 70–79 years in the Health, Aging and Body Composition Study. Associations of erythropoietin with incident HF, coronary heart disease (CHD), stroke, mortality, and ≥30% decline in estimated glomerular filtration rate (eGFR) were examined using Cox proportional hazards and logistic regression over 10.7 years of follow up. Mean (SD) age was 75 (3) years and median (quartile 1, quartile 3) erythropoietin was 12.3 (9.0, 17.2) mIU/mL. There were 503 incident HF events and each doubling of serum erythropoietin was associated with a 25% increased risk of incident HF 1.25 (95% CI 1.13, 1.48) after adjusting for demographics, prevalent cardiovascular disease (CVD), CVD risk factors, kidney function and serum hemoglobin. There was no interaction of serum erythropoietin with chronic kidney disease or anemia (p>0.50). There were 330 incident CHD events, 161 strokes, 1,112 deaths and 698 outcomes of ≥ 30% decline in eGFR. Serum erythropoietin was not significantly associated with these outcomes. Conclusions Higher levels of endogenous erythropoietin are associated with incident HF in older adults. Studies need to elucidate the mechanisms through which endogenous erythropoietin levels associate with specific outcomes. PMID:26721912

  15. Erythropoietin-Associated PRCA: Still an Unsolved Mystery.

    PubMed

    Schellekens, Huub; Jiskoot, Wim

    2006-09-01

    The peak of erythropoietin-associated pure red cell aplasia (PRCA) incidents occurred over 4 years ago, but the debate on what triggered the autoimmune disorder continues today. The association with the recombinant human erythropoietin (epoetin, rhEPO) alpha-branded Eprex (Johnson and Johnson), makes PRCA of interest to medical and scientific communities, as well as the biotechnology industry, as it opens a broader question of the potential immunogenicity of biopharmaceuticals in general. An overview of the background and a perspective on current thought in erythropoietin-associated PRCA may assist in avoiding a repeat of similar immunogenic cases with other biopharmaceuticals and their emerging follow-on products. At the same time, it is also important to clarify what are the relevant questions to ask in order to ensure appropriate testing in the regulation of biopharmaceuticals. The upsurge of PRCA is associated with a formulation change introduced in 1998 when human serum albumin (HSA) as protein stabilizer was exchanged with polysorbate 80. Several explanations have been offered to explain how this change led to Eprex-associated PRCA. Leachates from uncoated rubber stoppers acting as adjuvant are blamed by the manufacturer of Eprex, but the experimental data substantiating this claim are poor and the leachates theory has no biological rationale and is also inconsistent with epidemiological and clinical data. A more likely explanation that is consistent with all data is a higher tendency for aggregate formation during handling and storage due to the exchange of HSA by polysorbate 80 as stabilizer.

  16. [Tumor anemia. Overview of the role of human recombinant erythropoietin (r-hu-EPO) in treatment of tumor anemia].

    PubMed

    Monnerat, C; Leyvraz, S

    1999-01-28

    The prevalence of anaemia in patients with cancer lies between 10 and 40%, depending on the type of tumor and chemotherapy. Anaemia has a significant impact on the quality of life, along with pain or disease progression. There are multiple causes but the physiopathology resembles that of inflammatory anaemia. The following mechanisms can be distinguished: a resistance of the erythroid precursor cells (BFU-e, CFU-e) to erythropoietin, an inappropriately decreased renal erythropoietin secretion for a given haemoglobin value and alterations of the iron metabolism leading to a functional iron deficiency. Recombinant human erythropoietin (r-hu-EPO) is safe and efficient in the treatment of anaemia of chronic renal failure and rheumatoid arthritis. In oncology different phase I and II studies have demonstrated an efficacy (increase of haemoglobin, decrease of transfusion requirements) in about 50% of all adult patients. A response to a subcutaneous r-hu-EPO treatment with a relatively high posology of 150 U/kg three times a week can be expected after one to two months. No single reliable parameter will predict a response to the r-hu-EPO treatment. Several phase III studies confirm that anaemia in cancer patients undergoing chemotherapy (notably with cisplatin) can be corrected in 40 to 60% of all cases and that the haemoglobin increase improves the quality of life. Finally, recent clinical trials suggest that an early r-hu-EPO treatment might prevent the occurrence of anaemia secondary to chemotherapy. Several parameters will have to be specified such as the precise definition of the groups at risk, the appropriate haemoglobin level to initiate a r-hu-EPO treatment, its optimal posology, as well as the role of the iron substitution and its route of administration. The impact of the r-hu-EPO treatment on the quality of life of cancer patients constitutes a priority for future studies, which will have define the exact role of r-hu-EPO in oncology management.

  17. Designing a small molecule erythropoietin mimetic.

    PubMed

    Guarnieri, Frank

    2015-01-01

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

  18. Erythropoietin and carbamylated erythropoietin are neuroprotective following spinal cord hemisection in the rat.

    PubMed

    King, V R; Averill, S A; Hewazy, D; Priestley, J V; Torup, Lars; Michael-Titus, A T

    2007-07-01

    The cytokine erythropoietin (EPO) has been shown to be neuroprotective in a variety of models of central and peripheral nervous system injury. Derivatives of EPO that lack its erythropoietic effects have recently been developed, and the initial reports suggest that they have a neuroprotective potential comparable to that of EPO. One such derivative is carbamylated EPO (CEPO). In the current study we compared the effects of treatment with EPO and CEPO on some of the early neurodegenerative events that occur following spinal cord injury (SCI) induced by hemisection. Adult male Wistar rats received a unilateral hemisection of the spinal cord. Thirty minutes and 24 h following injury, animals received an intraperitoneal injection of saline, EPO (40 microg/kg) or CEPO (40 microg/kg). Results indicated that 3 days post-injury, both CEPO and EPO decreased to a similar extent the size of the lesion compared with control animals. Both compounds also decreased the number of terminal transferase-mediated dUTP nick-end labelling (TUNEL)-labelled apopotic nuclei around the lesion site, as well as the number of axons expressing the injury marker beta-amyloid precursor protein. EPO and CEPO also increased Schwann cell infiltration into the lesion site, although neither compound had any effect on macrophage infiltration either within the lesion site itself or in the surrounding intact tissue. In addition, immunohistochemistry showed an increased expression of both the EPO receptor and the beta common receptor subunit, the components of the receptor complex proposed to mediate the neuroprotective effects of EPO and CEPO in neurons near the site of the injury. The results show that not only does CEPO have an efficacy comparable to that of EPO in its neuroprotective potential following injury, but also that changes in the receptors for these compounds following SCI may underlie their neuroprotective efficacy.

  19. Phagocyte respiratory burst activates macrophage erythropoietin signalling to promote acute inflammation resolution

    PubMed Central

    Luo, Bangwei; Wang, Jinsong; Liu, Zongwei; Shen, Zigang; Shi, Rongchen; Liu, Yu-Qi; Liu, Yu; Jiang, Man; Wu, Yuzhang; Zhang, Zhiren

    2016-01-01

    Inflammation resolution is an active process, the failure of which causes uncontrolled inflammation which underlies many chronic diseases. Therefore, endogenous pathways that regulate inflammation resolution are fundamental and of wide interest. Here, we demonstrate that phagocyte respiratory burst-induced hypoxia activates macrophage erythropoietin signalling to promote acute inflammation resolution. This signalling is activated following acute but not chronic inflammation. Pharmacological or genetical inhibition of the respiratory burst suppresses hypoxia and macrophage erythropoietin signalling. Macrophage-specific erythropoietin receptor-deficient mice and chronic granulomatous disease (CGD) mice, which lack the capacity for respiratory burst, display impaired inflammation resolution, and exogenous erythropoietin enhances this resolution in WT and CGD mice. Mechanistically, erythropoietin increases macrophage engulfment of apoptotic neutrophils via PPARγ, promotes macrophage removal of debris and enhances macrophage migration to draining lymph nodes. Together, our results provide evidences of an endogenous pathway that regulates inflammation resolution, with important implications for treating inflammatory conditions. PMID:27397585

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

    PubMed

    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.

  1. Effects of Intraosseous Erythropoietin during Hemorrhagic Shock in Swine

    PubMed Central

    Borovnik-Lesjak, Vesna; Whitehouse, Kasen; Baetiong, Alvin; Miao, Yang; Currie, Brian M.; Velmurugan, Sathya; Radhakrishnan, Jeejabai; Gazmuri, Raúl J.

    2014-01-01

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

  2. Erythropoietin-dependent anaemia: a possible complication of diabetic neuropathy.

    PubMed

    Hadjadj, S; Torremocha, F; Fanelli, A; Brizard, A; Bauwens, M; Maréchaud, R

    2001-06-01

    We report the case of a 52-year-old woman with long-term type 1 diabetes mellitus, complicated with proliferative retinopathy, autonomic neuropathy and microalbuminuria and moderate renal failure. A normochromic, normocytic are generative anaemia had been diagnosed for three years. Clinical and biological investigations for the aetiology of anaemia remained normal or negative. Anaemia was associated with a concentration of erythropoietin (EPO) in the normal range, but inappropriately low regarding anaemia. Treatment with recombinant EPO induced a rapid increase in haemoglobin level and improved the patient's quality of life. The role of diabetic neuropathy in the genesis of anaemia, in conjunction with a modest renal impairment is discussed.

  3. Tissue protection by erythropoietin: new findings in a moving field.

    PubMed

    Nangaku, Masaomi

    2013-09-01

    Two groups elucidate novel mechanisms of tissue protection by erythropoietin (EPO). Hu et al. demonstrate that Klotho's protective effect against oxidant-induced cytotoxicity is partially mediated by an increase in the endogenous expression of the classical EPO receptor (EpoR). While erythropoiesis is stimulated by the canonical EpoR homodimer, the tissue-protective effects of EPO are mediated through a heterodimeric 'tissue-protective' receptor. Coldewey et al. demonstrate a protective role of the 'tissue-protective' EpoR against acute kidney injury.

  4. Expression of adrenomedullin in rats after spinal cord injury and intervention effect of recombinant human erythropoietin.

    PubMed

    Zhao, Liang; Jing, Yu; Qu, Lin; Meng, Xiangwei; Cao, Yang; Tan, Huibing

    2016-12-01

    The expression of adrenomedullin (ADM) in injured tissue of rat spinal cord was observed and the effect of recombinant human erythropoietin was analyzed. A total of 45 Sprague-Dawley rats were selected and divided into 3 equal groups including, a sham-operation group in which rats received an excision of vertebral plate; a spinal cord injury model group and a recombinant human erythropoietin group in which rats with spinal cord injury received a caudal vein injection of 300 units recombinant human erythropoietin after injury. Hematoxylin and eosin staining was performed to observe the spinal cord injury conditions. Immunohistochemical staining was performed to observe the expression of ADM. Pathologic changes in the group of recombinant human erythropoietin at various times were significantly less severe than those in the group of spinal cord injury model. The expression of ADM was increased particularly in the group of recombinant human erythropoietin (P<0.01). The improved Tarlov scores of the group of spinal cord injury model and the group of recombinant human erythropoietin were lower than those of the sham-operation group at 3, 6 and 9 days (P<0.01). Thus, the recombinant human erythropoietin is capable of alleviating the secondary injury of spinal cord. One of the mechanisms may be achieved by promoting the increase of ADM expression.

  5. Expression of adrenomedullin in rats after spinal cord injury and intervention effect of recombinant human erythropoietin

    PubMed Central

    Zhao, Liang; Jing, Yu; Qu, Lin; Meng, Xiangwei; Cao, Yang; Tan, Huibing

    2016-01-01

    The expression of adrenomedullin (ADM) in injured tissue of rat spinal cord was observed and the effect of recombinant human erythropoietin was analyzed. A total of 45 Sprague-Dawley rats were selected and divided into 3 equal groups including, a sham-operation group in which rats received an excision of vertebral plate; a spinal cord injury model group and a recombinant human erythropoietin group in which rats with spinal cord injury received a caudal vein injection of 300 units recombinant human erythropoietin after injury. Hematoxylin and eosin staining was performed to observe the spinal cord injury conditions. Immunohistochemical staining was performed to observe the expression of ADM. Pathologic changes in the group of recombinant human erythropoietin at various times were significantly less severe than those in the group of spinal cord injury model. The expression of ADM was increased particularly in the group of recombinant human erythropoietin (P<0.01). The improved Tarlov scores of the group of spinal cord injury model and the group of recombinant human erythropoietin were lower than those of the sham-operation group at 3, 6 and 9 days (P<0.01). Thus, the recombinant human erythropoietin is capable of alleviating the secondary injury of spinal cord. One of the mechanisms may be achieved by promoting the increase of ADM expression. PMID:28101163

  6. [Is there still a role for recombinant erythropoietin in the management of anaemia of critical illness?].

    PubMed

    Muñoz, Manuel; Ramón Leal-Noval, Santiago; García-Erce, José Antonio

    2009-05-23

    There is a high prevalence of anaemia among patients admitted to the intensive care unit (ICU), and it may have a negative effect on patient's outcome. The most common treatment for anaemia in the ICU patient is allogeneic blood transfusion (ABT), yet it has been found to be a risk factor associated with an increased risk of morbidity and mortality in critical care patients. As a reduction of erythropoietin secretion and action is observed in most ICU patients, the administration of (rHuEPO) has emerged as a therapeutic option. Unfortunately, the results from different studies show that rHuEPO treatment results in a small reduction of ABT requirements when "restrictive" transfusion criteria are applied, which has only been supported by three of the studies. Yet this did not result in a decreased mortality rate, except for patients with a diagnosis on admission of trauma in two studies, even though one study reported a dose-dependent increase of thrombotic vascular events among patients without thromboprophylaxis. Altogether, clinical data suggest a role for rHuEPO in the treatment of anaemia in trauma patients, especially in those sustaining neurotrauma, whereas for non-trauma patients without an approved indication, rHuEPO administration is an expensive approach, does not seem to improve outcome, and might result in serious adverse effects. Consequently, more basic and clinical studies are required to ascertain which patients are more likely to benefit from these treatments, as well as to identify the optimal doses and administration schedules, and iron administration.

  7. Involvement of BDNF and NGF in the mechanism of neuroprotective effect of human recombinant erythropoietin nanoforms.

    PubMed

    Solev, I N; Balabanyan, V Yu; Volchek, I A; Elizarova, O S; Litvinova, S A; Garibova, T L; Voronina, T A

    2013-06-01

    Human recombinant erythropoietin adsorbed on poly(butyl)cyanoacrylate nanoparticles and administered intraperitoneally in a dose of 0.05 mg/kg exhibited a neuroprotective effect in experimental intracerebral posttraumatic hematomas (hemorrhagic stroke) and reduced animal mortality. Human recombinant erythropoietin, native and adsorbed on lactic and glycolic acid copolymer-based nanoparticles, exhibited no antistroke effect on this model. Analysis of reverse transcription PCR products showed that human recombinant erythropoietin adsorbed on poly(butyl)cyanoacrylate nanoparticles more than 2-fold increased the expression of BDNF and NGF neurotrophins in the rat brain frontal cortex and hippocampus.

  8. The effect of erythropoietin on normal and neoplastic cells

    PubMed Central

    Elliott, Steve; Sinclair, Angus M

    2012-01-01

    Erythropoietin (Epo) is an essential hormone that binds and activates the Epo receptor (EpoR) resident on the surface of erythroid progenitor cells, thereby promoting erythropoiesis. Recombinant human erythropoietin has been used successfully for over 20 years to treat anemia in millions of patients. In addition to erythropoiesis, Epo has also been reported to have other effects, such as tissue protection and promotion of tumor cell growth or survival. This became of significant concern in 2003, when some clinical trials in cancer patients reported increased tumor progression and worse survival outcomes in patients treated with erythropoiesis-stimulating agents (ESAs). One of the potential mechanisms proffered to explain the observed safety issues was that functional EpoR was expressed in tumors and/or endothelial cells, and that ESAs directly stimulated tumor growth and/or antagonized tumor ablative therapies. Since then, numerous groups have performed further research evaluating this potential mechanism with conflicting data and conclusions. Here, we review the biology of endogenous Epo and EpoR expression and function in erythropoiesis, and evaluate the evidence pertaining to the expression of EpoR on normal nonhematopoietic and tumor cells. PMID:22848149

  9. Protective role of erythropoietin during testicular torsion of the rats.

    PubMed

    Yazihan, Nuray; Ataoglu, Haluk; Koku, Naim; Erdemli, Esra; Sargin, Ayse Kose

    2007-10-01

    Testicular torsion is an important clinical urgency. Similar mechanisms occurred after detorsion of the affected testis as in the ischemia reperfusion (I/R) damage. This study was designed to investigate the effects of erythropoietin (EPO) treatment after unilateral testicular torsion. Fifty male Sprague-Dawley rats were divided into five groups. Group 1 underwent a sham operation of the right testis under general anesthesia. Group 2 was same as sham, and EPO (3,000 IU/kg) infused i.p., group 3 underwent a similar operation but the right testis was rotated 720 degrees clockwise for 1 h, maintained by fixing the testis to the scrotum, and saline infused during the procedure. Group 4 underwent similar torsion but EPO was infused half an hour before the detorsion procedure, and in group 5, EPO was infused after detorsion procedure. Four hours after detorsion, ipsilateral and contralateral testes were taken out for evaluation. Treatment with EPO improved testicular structures in the ipsilateral testis but improvement was less in the contralateral testis histologically, but EPO treatment decreased germ cell apoptosis in both testes following testicular IR. TNF-alpha, IL-1beta, IL-6 and nitrite levels decreased after EPO treatment especially in the ipsilateral testis. We conclude that testicular I/R causes an increase in germ cell apoptosis both in the ipsilateral and contralateral testes. Erythropoietin has antiapoptotic and anti-inflammatory effects following testicular torsion.

  10. Erythropoietin Activates Mitochondrial Biogenesis and Couples Red Cell Mass to Mitochondrial Mass in the Heart

    EPA Science Inventory

    RATIONALE: Erythropoietin (EPO) is often administered to cardiac patients with anemia, particularly from chronic kidney disease, and stimulation of erythropoiesis may stabilize left ventricular and renal function by recruiting protective effects beyond the correction of anemia. O...

  11. Erythropoietin inhibits liver gelatinases during galactosamine-induced hepatic damage in rats.

    PubMed

    Madro, Agnieszka; Kurzepa, Jacek; Czechowska, Grazyna; Słomka, Maria; Celiński, Krzysztof; Szymonik-Lesiuk, Stanisława

    2009-01-01

    Matrix metalloproteinase (MMP)-2 and -9 (gelatinases) participate in extracellular protein remodeling. Moreover, they are involved in the development of hepatic fibrosis. The goal of this study was to evaluate liver gelatinase activities after erythropoietin (Epo) treatment (1U/dose, sc) in experimentally damaged livers of rats treated with D-galactosamine (Gal, 800 mg/kg/dose, ip). Sixty rats were divided into six equal groups: I - received 5 doses of Epo and a single dose of Gal [the experiment duration (ED): 10 days]; II - received 5 doses of Epo and 3 doses of Gal (ED: 14 days); III - received only 5 doses of Epo (ED: 9 days); IV - received 3 doses of Gal (ED: 5 days);V - received a single dose of Gal (ED: 1 day); VI - control group (ED: 9 days). The animals were sacrificed and the livers were collected 48 h after the last drug administration. The activity of gelatinases was measured using gelatin zymography. No fluctuations in gelatinase activities were observed after the administration of a single dose of Gal in comparison to the control group. However, a significant increase in gelatinase activities was observed after treatment with three doses of Gal. Five doses of Epo administrated before Gal treatment prevented elevated gelatinase activities: MMP-9 activity was comparable to control, and MMP-2 activity was decreased (group II). The gelatinase activities was lower in group I and II in comparison to the control group. These results revealed that Epo decreases MMP-2 and MMP-9 activity, suggesting that it is a hepatoprotective agent against hepatic damage induced by galactosamine injection.

  12. Erythropoietin modulates the structure of bone morphogenetic protein 2-engineered cranial bone.

    PubMed

    Sun, Hongli; Jung, Younghun; Shiozawa, Yusuke; Taichman, Russell S; Krebsbach, Paul H

    2012-10-01

    The ideally engineered bone should have similar structural and functional properties to the native tissue. Although structural integrity is critical for functional bone regeneration, we know less about modulating the structural properties of the engineered bone elicited by bone morphogenetic protein (BMP) than efficacy and safety. Erythropoietin (Epo), a primary erythropoietic hormone, has been used to augment blood transfusion in orthopedic surgery. However, the effects of Epo on bone regeneration are not well known. Here, we determined the role of Epo in BMP2-induced bone regeneration using a cranial defect model. Epo administration improved the quality of BMP2-induced bone and more closely resembled natural cranial bone with a higher bone volume (BV) fraction and lower marrow fraction when compared with BMP2 treatment alone. Epo increased red blood cells (RBCs) in peripheral blood and also increased hematopoietic and mesenchymal stem cell (MSC) populations in bone marrow. Consistent with our previous work, Epo increased osteoclastogenesis both in vitro and in vivo. Results from a metatarsal organ culture assay suggested that Epo-promoted osteoclastogenesis contributed to angiogenesis because angiogenesis was blunted when osteoclastogenesis was blocked by alendronate (ALN) or osteoprotegerin (OPG). Earlier calcification of BMP2-induced temporary chondroid tissue was observed in the Epo+BMP group compared to BMP2 alone. We conclude that Epo significantly enhanced the outcomes of BMP2-induced cranial bone regeneration in part through its actions on osteoclastogenesis and angiogenesis.

  13. Erythropoietin-mediated tissue protection: reducing collateral damage from the primary injury response.

    PubMed

    Brines, M; Cerami, A

    2008-11-01

    In its classic hormonal role, erythropoietin (EPO) is produced by the kidney and regulates the number of erythrocytes within the circulation to provide adequate tissue oxygenation. EPO also mediates other effects directed towards optimizing oxygen delivery to tissues, e.g. modulating regional blood flow and reducing blood loss by promoting thrombosis within damaged vessels. Over the past 15 years, many unexpected nonhaematopoietic functions of EPO have been identified. In these more recently appreciated nonhormonal roles, locally-produced EPO signals through a different receptor isoform and is a major molecular component of the injury response, in which it counteracts the effects of pro-inflammatory cytokines. Acutely, EPO prevents programmed cell death and reduces the development of secondary, pro-inflammatory cytokine-induced injury. Within a longer time frame, EPO provides trophic support to enable regeneration and healing. As the region immediately surrounding damage is typically relatively deficient in endogenous EPO, administration of recombinant EPO can provide increased tissue protection. However, effective use of EPO as therapy for tissue injury requires higher doses than for haematopoiesis, potentially triggering serious adverse effects. The identification of a tissue-protective receptor isoform has facilitated the engineering of nonhaematopoietic, tissue-protective EPO derivatives, e.g. carbamyl EPO, that avoid these complications. Recently, regions within the EPO molecule mediating tissue protection have been identified and this has enabled the development of potent tissue-protective peptides, including some mimicking EPO's tertiary structure but unrelated in primary sequence.

  14. Erythropoietin responsive cardiomyogenic cells contribute to heart repair post myocardial infarction.

    PubMed

    Zafiriou, Maria Patapia; Noack, Claudia; Unsöld, Bernhard; Didie, Michael; Pavlova, Elena; Fischer, Henrike J; Reichardt, Holger M; Bergmann, Martin W; El-Armouche, Ali; Zimmermann, Wolfram-Hubertus; Zelarayan, Laura Cecilia

    2014-09-01

    The role of erythropoietin (Epo) in myocardial repair after infarction remains inconclusive. We observed high Epo receptor (EPOR) expression in cardiac progenitor cells (CPCs). Therefore, we aimed to characterize these cells and elucidate their contribution to myocardial regeneration on Epo stimulation. High EPOR expression was detected during murine embryonic heart development followed by a marked decrease until adulthood. EPOR-positive cells in the adult heart were identified in a CPC-enriched cell population and showed coexpression of stem, mesenchymal, endothelial, and cardiomyogenic cell markers. We focused on the population coexpressing early (TBX5, NKX2.5) and definitive (myosin heavy chain [MHC], cardiac Troponin T [cTNT]) cardiomyocyte markers. Epo increased their proliferation and thus were designated as Epo-responsive MHC expressing cells (EMCs). In vitro, EMCs proliferated and partially differentiated toward cardiomyocyte-like cells. Repetitive Epo administration in mice with myocardial infarction (cumulative dose 4 IU/g) resulted in an increase in cardiac EMCs and cTNT-positive cells in the infarcted area. This was further accompanied by a significant preservation of cardiac function when compared with control mice. Our study characterized an EPO-responsive MHC-expressing cell population in the adult heart. Repetitive, moderate-dose Epo treatment enhanced the proliferation of EMCs resulting in preservation of post-ischemic cardiac function.

  15. Revisiting adult neurogenesis and the role of erythropoietin for neuronal and oligodendroglial differentiation in the hippocampus.

    PubMed

    Hassouna, I; Ott, C; Wüstefeld, L; Offen, N; Neher, R A; Mitkovski, M; Winkler, D; Sperling, S; Fries, L; Goebbels, S; Vreja, I C; Hagemeyer, N; Dittrich, M; Rossetti, M F; Kröhnert, K; Hannke, K; Boretius, S; Zeug, A; Höschen, C; Dandekar, T; Dere, E; Neher, E; Rizzoli, S O; Nave, K-A; Sirén, A-L; Ehrenreich, H

    2016-12-01

    Recombinant human erythropoietin (EPO) improves cognitive performance in neuropsychiatric diseases ranging from schizophrenia and multiple sclerosis to major depression and bipolar disease. This consistent EPO effect on cognition is independent of its role in hematopoiesis. The cellular mechanisms of action in brain, however, have remained unclear. Here we studied healthy young mice and observed that 3-week EPO administration was associated with an increased number of pyramidal neurons and oligodendrocytes in the hippocampus of ~20%. Under constant cognitive challenge, neuron numbers remained elevated until >6 months of age. Surprisingly, this increase occurred in absence of altered cell proliferation or apoptosis. After feeding a (15)N-leucine diet, we used nanoscopic secondary ion mass spectrometry, and found that in EPO-treated mice, an equivalent number of neurons was defined by elevated (15)N-leucine incorporation. In EPO-treated NG2-Cre-ERT2 mice, we confirmed enhanced differentiation of preexisting oligodendrocyte precursors in the absence of elevated DNA synthesis. A corresponding analysis of the neuronal lineage awaits the identification of suitable neuronal markers. In cultured neurospheres, EPO reduced Sox9 and stimulated miR124, associated with advanced neuronal differentiation. We are discussing a resulting working model in which EPO drives the differentiation of non-dividing precursors in both (NG2+) oligodendroglial and neuronal lineages. As endogenous EPO expression is induced by brain injury, such a mechanism of adult neurogenesis may be relevant for central nervous system regeneration.

  16. Erythropoietin attenuates loss of potassium chloride co-transporters following prenatal brain injury.

    PubMed

    Jantzie, L L; Getsy, P M; Firl, D J; Wilson, C G; Miller, R H; Robinson, S

    2014-07-01

    Therapeutic agents that restore the inhibitory actions of γ-amino butyric acid (GABA) by modulating intracellular chloride concentrations will provide novel avenues to treat stroke, chronic pain, epilepsy, autism, and neurodegenerative and cognitive disorders. During development, upregulation of the potassium-chloride co-transporter KCC2, and the resultant switch from excitatory to inhibitory responses to GABA guide the formation of essential inhibitory circuits. Importantly, maturation of inhibitory mechanisms is also central to the development of excitatory circuits and proper balance between excitatory and inhibitory networks in the developing brain. Loss of KCC2 expression occurs in postmortem samples from human preterm infant brains with white matter lesions. Here we show that late gestation brain injury in a rat model of extreme prematurity impairs the developmental upregulation of potassium chloride co-transporters during a critical postnatal period of circuit maturation in CA3 hippocampus by inducing a sustained loss of oligomeric KCC2 via a calpain-dependent mechanism. Further, administration of erythropoietin (EPO) in a clinically relevant postnatal dosing regimen following the prenatal injury protects the developing brain by reducing calpain activity, restoring oligomeric KCC2 expression and attenuating KCC2 fragmentation, thus providing the first report of a safe therapy to address deficits in KCC2 expression. Together, these data indicate it is possible to reverse abnormalities in KCC2 expression during the postnatal period, and potentially reverse deficits in inhibitory circuit formation central to cognitive impairment and epileptogenesis.

  17. Erythropoietin, testosterone, and thyroxine in the erythropoietic response of the snake, Xenochrophis piscator.

    PubMed

    Pati, A K; Thapliyal, J P

    1984-03-01

    The erythropoietic response of snakes was examined after injecting human urinary erythropoietin (Ep), testosterone propionate (TP), and L-thyroxine (T4), separately and in combinations, into starved ophids. The effect of starvation was reflected by a decrease in the number of erythrocytes, a fall in hemoglobin concentration, and a decline in hematocrit. Statistically significant elevation of erythrocyte number, hemoglobin concentration, and hematocrit was observed at 24 hr following the administration of Ep + T4, and Ep + TP + T4 into starved ophids. The erythrocyte number was also increased by T4 treatment at 24 hr. Furthermore, while T4 and Ep individually increased the red blood cell number at 168 hr, T4, TP + T4, and Ep + TP + T4 elevated the hemoglobin concentration and Ep + T4 and Ep + TP + T4 increased the hematocrit value. It is suggested that the influence of any one of the hormones utilized in the present study on blood morphology of fasted snakes depends to a greater extent on the presence or absence of the other hormone(s).

  18. Revisiting adult neurogenesis and the role of erythropoietin for neuronal and oligodendroglial differentiation in the hippocampus

    PubMed Central

    Hassouna, I; Ott, C; Wüstefeld, L; Offen, N; Neher, R A; Mitkovski, M; Winkler, D; Sperling, S; Fries, L; Goebbels, S; Vreja, I C; Hagemeyer, N; Dittrich, M; Rossetti, M F; Kröhnert, K; Hannke, K; Boretius, S; Zeug, A; Höschen, C; Dandekar, T; Dere, E; Neher, E; Rizzoli, S O; Nave, K-A; Sirén, A-L; Ehrenreich, H

    2016-01-01

    Recombinant human erythropoietin (EPO) improves cognitive performance in neuropsychiatric diseases ranging from schizophrenia and multiple sclerosis to major depression and bipolar disease. This consistent EPO effect on cognition is independent of its role in hematopoiesis. The cellular mechanisms of action in brain, however, have remained unclear. Here we studied healthy young mice and observed that 3-week EPO administration was associated with an increased number of pyramidal neurons and oligodendrocytes in the hippocampus of ~20%. Under constant cognitive challenge, neuron numbers remained elevated until >6 months of age. Surprisingly, this increase occurred in absence of altered cell proliferation or apoptosis. After feeding a 15N-leucine diet, we used nanoscopic secondary ion mass spectrometry, and found that in EPO-treated mice, an equivalent number of neurons was defined by elevated 15N-leucine incorporation. In EPO-treated NG2-Cre-ERT2 mice, we confirmed enhanced differentiation of preexisting oligodendrocyte precursors in the absence of elevated DNA synthesis. A corresponding analysis of the neuronal lineage awaits the identification of suitable neuronal markers. In cultured neurospheres, EPO reduced Sox9 and stimulated miR124, associated with advanced neuronal differentiation. We are discussing a resulting working model in which EPO drives the differentiation of non-dividing precursors in both (NG2+) oligodendroglial and neuronal lineages. As endogenous EPO expression is induced by brain injury, such a mechanism of adult neurogenesis may be relevant for central nervous system regeneration. PMID:26809838

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

    NASA Astrophysics Data System (ADS)

    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.

  20. Erythropoietin preserves the integrity and quality of organs for transplantation after cardiac death.

    PubMed

    Maio, Rui; Sepodes, Bruno; Patel, Nimesh S A; Thiemermann, Christoph; Mota-Filipe, Helder; Costa, Paulo

    2011-02-01

    Previous studies have shown that treatment with erythropoietin (EPO) exerts important cytoprotective and antiapoptotic effects. Donor organs recovered after cardiac death (DCD) can alleviate the shortage of organs required for transplantation. However, organs obtained subsequent to cardiac death demonstrate an increased incidence of delayed graft function and primary nonfunction. The aim of this study was to determine the effects of EPO administration to the donor in a porcine model of kidney transplantation under DCD conditions. Landrace pigs received 1,000 IU/kg i.v. EPO 30 min before cardiac arrest. Kidneys were then subjected to 30 min of warm ischemia and were transplanted after 24 h of cold storage. Renal dysfunction, injury, and inflammation were evaluated 4 h after transplantation. Transplantation of kidneys from DCD resulted in significant renal dysfunction, injury, and inflammation. This study provides the first evidence that pretreatment of the donor with a single pharmacologically relevant dose of EPO causes substantial attenuation of the dysfunction and injury associated with the transplantation of kidneys recovered after cardiac death.

  1. Effects of Erythropoietin on Adipose Tissue: A Possible Strategy in Refilling

    PubMed Central

    Sabbatini, Maurizio; Bosetti, Michela; Borrone, Alessia; Boldorini, Renzo; Taveggia, Antonio; Verna, Giovanni; Cannas, Mario

    2015-01-01

    Background: The increased resorption and the difficulty of the fat graft take following autologous fat transplantation procedure are associated with reduced fat tissue revascularization and increased apoptosis of adipose cells. We suppose that the lipofilling procedure induces an inflammatory environment within the fat graft mass, whose evolution influences the efficacy of autologous fat graft survival. Erythropoietin (EPO) is a glycoprotein hormone known to exert angiogenetic and anti-inflammatory effects; therefore, our purpose was to investigate its reaction with adipose tissue used in lipofilling. Methods: Fat masses were harvested using manual suction lipectomy and then seeded on dishes in appropriate culture and treated for 3 weeks with 3 doses of EPO. CD31 and CD68 immunohistochemistry was used to identify microvessels and several infiltrating leukocyte cells. Results: Following EPO administration, we have detected an increase in the number of CD31-positive microvessel endothelium cells and CD31-positive small leukocytes and a reduction of CD68-positive cells. These effects were more conspicuous following higher EPO dose. Conclusions: Our findings evidence EPO treatment as a useful strategy to sustain the revascularization of grafted tissue and to reduce its inflammatory state. PMID:26034645

  2. Erythropoietin reduces storage lesions and decreases apoptosis indices in blood bank red blood cells

    PubMed Central

    Penuela, Oscar Andrés; Palomino, Fernando; Gómez, Lina Andrea

    2015-01-01

    Background Recent evidence shows a selective destruction of the youngest circulating red blood cells (neocytolysis) trigged by a drop in erythropoietin levels. Objective The aim of this study was to evaluate the effect of recombinant human erythropoietin beta on the red blood cell storage lesion and apoptosis indices under blood bank conditions. Methods Each one of ten red blood cell units preserved in additive solution 5 was divided in two volumes of 100 mL and assigned to one of two groups: erythropoietin (addition of 665 IU of recombinant human erythropoietin) and control (isotonic buffer solution was added). The pharmacokinetic parameters of erythropoietin were estimated and the following parameters were measured weekly, for six weeks: Immunoreactive erythropoietin, hemolysis, percentage of non-discocytes, adenosine triphosphate, glucose, lactate, lactate dehydrogenase, and annexin-V/esterase activity. The t-test or Wilcoxon's test was used for statistical analysis with significance being set for a p-value <0.05. Results Erythropoietin, when added to red blood cell units, has a half-life >6 weeks under blood bank conditions, with persistent supernatant concentrations of erythropoietin during the entire storage period. Adenosine triphosphate was higher in the Erythropoietin Group in Week 6 (4.19 ± 0.05 μmol/L vs. 3.53 ± 0.02 μmol/L; p-value = 0.009). The number of viable cells in the Erythropoietin Group was higher than in the Control Group (77% ± 3.8% vs. 71% ± 2.3%; p-value <0.05), while the number of apoptotic cells was lower (9.4% ± 0.3% vs. 22% ± 0.8%; p-value <0.05). Conclusions Under standard blood bank conditions, an important proportion of red blood cells satisfy the criteria of apoptosis. Recombinant human erythropoietin beta seems to improve storage lesion parameters and mitigate apoptosis. PMID:26969770

  3. [Application of recombinant erythropoietin during preparation for hepatic transplantation operation from the living kindred donor].

    PubMed

    Kotenko, O G; Mazur, A P; Dykhovichnaia, N Iu; Popov, A O; Gusev, A V

    2007-07-01

    First experience of application of the blood autodonorship programme, using recombinant erythropoietin (Eprex) plus preparations containing iron during their preparation for partial hepatic resection, was analyzed. Realization of this programme had permitted to escape the performance of allogenic hemotransfusion in 71.4% of donors, in whom the right or left hepatic lobe was taken out and in 100%--the left lateral section. The erythropoietin dosage regimes in different types of hepatic resections in living kindred donors were proposed.

  4. Anti-Inflammatory Effect of Erythropoietin in the TNBS-induced Colitis.

    PubMed

    Mateus, Vanessa; Rocha, João; Alves, Paula; Mota-Filipe, Helder; Sepodes, Bruno; Pinto, Rui Manuel Amaro

    2017-02-01

    Erythropoietin is a potent stimulator of erythroid progenitor cells, which is able to inhibit NF-kB activation, due to its pleiotropic properties, thus promoting an anti-inflammatory effect. As inflammatory bowel disease is a chronic disease with reduced quality of life, and the current pharmacotherapy only induces or maintains the patient in remission, there is a crucial need of new pharmacological approaches. The main objective of this study was to evaluate the effect of erythropoietin in the TNBS-induced colitis model in mice with a normal intestinal flora. Mice with TNBS-induced colitis were treated with a daily dose of erythropoietin at 500 IU/kg bw/day and 1000 IU/Kg bw/day IP during 4 days. As to clinical symptoms/signs, erythropoietin attenuated the decreased body-weight and reduced diarrhoea and oedema of the anus registered in the non-treated mice group in a dose-dependent manner. The anti-inflammatory properties of erythropoietin in the TNBS-induced colitis were confirmed by suppression of pro-inflammatory mediators, such as TNF-α, IL-1β and MPO, as well as a significant increase in the anti-inflammatory cytokine, IL-10, was promoted. These treated mice also presented a reduction in haemoglobin faecal and ALP, suggesting a beneficial effect of erythropoietin in the haemorrhagic focus and destruction of the enterocyte associated with the colon injury induced by TNBS, respectively. The histopathological score was reduced after treatment with erythropoietin, decreasing the severity and extension of the colitis. Furthermore, renal and hepatic biomarkers, as well as haematocrit concentration, remained stabilized after treatment. In conclusion, erythropoietin reduces the inflammatory response associated with TNBS-induced colitis in mice.

  5. Rechallenge with intravenous recombinant human erythropoietin can be successful following the treatment of anti-recombinant erythropoietin associated pure red cell aplasia.

    PubMed

    Praditpornsilpa, Kearkiat; Tiranathanakul, Khajohn; Jootar, Saengsuree; Tungsanga, Kriang; Eiam-Ong, Somchai

    2014-05-01

    Anti recombinant human erythropoietin (r-HuEpo) associated pure red cell aplasia (PRCA) is an immunologic adverse effect of using subcutaneous r-HuEpo. Immunosuppressive agents have been suggested as treatment of this serious complication. After the reversal of anti-r-HuEpo antibody, the patients continue to have renal anemia and require long-term blood transfusion, albeit less frequently than when the antibody is positive. It is controversial whether re-challenging the patients with r-HuEpo is appropriate because re-challenging may cause the reappearance of the antibody. To balance the risk of antir-HuEpo antibody reappearance and longterm blood transfusion complications, we re-challenged r-HuEpo in five anti-r-HuEpo associated PRCA cases after a successful reversal of antibody using prednisolone in combination with cyclophosphamide. The rechallenge was performed intravenously since there were no reports of anti-r-HuEpo associated PRCA cases using this administration route. The duration after the reversal of antibody was 2.4 months before the re-challenge. Two patients were immediately re-challenged as soon as the antibodies reversed. After rechallenge with intravenous r-HuEpo, all patients responded to r-HuEpo: target level of Hb was maintained, blood transfusion was not required, and anti-r-HuEpo was consistently negative. All patients were followed for at least 6 months after re-challenge. Our data suggest that re-challenge with intravenous r-HuEpo can successfully treat anti- r-HuEpo associated PRCA.

  6. Erythropoietin modulates the neural control of hypoxic ventilation.

    PubMed

    Gassmann, Max; Soliz, Jorge

    2009-11-01

    Numerous factors involved in general homeostasis are able to modulate ventilation. Classically, this comprises several kind of molecules, including neurotransmitters and steroids that are necessary for fine tuning ventilation under different conditions such as sleep, exercise, and acclimatization to high altitude. Recently, however, we have found that erythropoietin (Epo), the main regulator of red blood cell production, influences both central (brainstem) and peripheral (carotid bodies) respiratory centers when the organism is exposed to hypoxic conditions. Here, we summarize the effect of Epo on the respiratory control in mammals and highlight the potential implication of Epo in the ventilatory acclimatization to high altitude, as well as in the several respiratory sickness and syndromes occurring at low and high altitude.

  7. The role of recombinant erythropoietin in childhood cancer.

    PubMed

    Shankar, Ananth Gouri

    2008-02-01

    Anemia in children with cancer is not an uncommon complication and is usually multifactorial in etiology. In numerous trials in adult cancer patients, treatment with recombinant erythropoietin has been shown to increase hemoglobin levels, reduce red blood cell transfusion requirements, and improve quality of life. Much less has been published of its use in the prevention or treatment of cancer-associated anemia (CAA) in children, in whom chemotherapy is usually more intensive and likely to result in greater myelosuppression. This review critically evaluates the published evidence of its use in childhood cancer especially; its safety and efficacy in the prevention and treatment of CAA and some indications for its use in childhood cancer are suggested.

  8. Procedures for monitoring recombinant erythropoietin and analogues in doping control.

    PubMed

    Segura, Jordi; Pascual, José A; Gutiérrez-Gallego, Ricardo

    2007-08-01

    The present report summarizes the main analytical strategies developed to identify the presence of recombinant erythropoietin (EPO) administered as a doping agent. Indirect evidence is based on the analysis of blood parameters (haemoglobin, haematocrit, reticulocytes, macrocytes, etc.) and serum markers (concentration of EPO and serum transferrin receptors, etc.). The problem of intertechnique comparison for reliable results evaluation is emphasized, especially for serum markers. Charge differences between isoforms of recombinant EPO and native urinary EPO are the grounds for the isoelectric focusing-double blotting-chemiluminescence detection method presently approved for doping control. Works addressing its advantages and limitations are presented and commented on. The chemical bases of the differential detection are highlighted and some future approaches for detection are also presented. The appearance and detectability of EPO analogues and mimetics susceptible for abuse are also addressed.

  9. From neurogenesis to neuroprotection in the epilepsy: signalling by erythropoietin.

    PubMed

    Castaneda-Arellano, Rolando; Beas-Zarate, Carlos; Feria-Velasco, Alfredo I; Bitar-Alatorre, Emilio W; Rivera-Cervantes, Martha C

    2014-06-01

    Epilepsy is a disorder characterised by recurrent seizures and molecular events, including the activation of early expression genes and the post-translational modifications of functional proteins. These events lead to changes in neurogenesis, mossy fibre sprouting, network reorganisation and neuronal death. The role of these events is currently a matter of great debate, especially as they relate to protection, repair, or further brain injury. In recent years, accumulating data have supported the idea that erythropoietin (EPO) regulates biological processes including neuroprotection and neurogenesis in several diseases, such as epilepsy. This review summarises the role of EPO in some of the molecular mechanisms involved in these events that could direct a more detailed approach for its use as a therapeutic alternative in reducing epileptic seizures.

  10. Erythropoietin: new approaches to improved molecular designs and therapeutic alternatives.

    PubMed

    Debeljak, N; Sytkowski, A J

    2008-01-01

    Erythropoietin (Epo) is a glycoprotein hormone that is the prime regulator of erythropoiesis. Recombinant Epo is a highly effective pharmaceutical used to correct anemias associated with renal insufficiency, cancer and other diseases. Efforts to increase its efficacy in vivo by manipulating the protein's structure have met with some success, and novel Epo-like agents are in development. Additionally, efforts to create Epo mimetic agents are underway, as is the design of agents to increase endogenous production. Because Epo has tissue protective actions outside of erythropoiesis, other designs have focused on producing erythropoietically inactive molecules that still retain extra-hematopoietic activity. The demonstration that Epo can trigger signaling in some cancer cells with, potentially, adverse effects on patient health has raised warning signs in the medical community and has gained the attention of regulatory authorities.

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

    PubMed Central

    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

    2016-01-01

    BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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. PMID:26908704

  12. Human rhabdomyosarcoma cells express functional erythropoietin receptor: Potential therapeutic implications

    PubMed Central

    PONIEWIERSKA-BARAN, AGATA; SUSZYNSKA, MALWINA; SUN, WENYUE; ABDELBASET-ISMAIL, AHMED; SCHNEIDER, GABRIELA; BARR, FREDERIC G.; RATAJCZAK, MARIUSZ Z.

    2015-01-01

    The erythropoietin receptor (EpoR) is expressed by cells from the erythroid lineage; however, evidence has accumulated that it is also expressed by some solid tumors. This is an important observation, because recombinant erythropoietin (EPO) is employed in cancer patients to treat anemia related to chemo/radiotherapy. In our studies we employed eight rhabdomyosarcoma (RMS) cell lines (three alveolar-type RMS cell lines and five embrional-type RMS cell lines), and mRNA samples obtained from positive, PAX7-FOXO1-positive, and fusion-negative RMS patient samples. Expression of EpoR was evaluated by RT-PCR, gene array and FACS. The functionality of EpoR in RMS cell lines was evaluated by chemotaxis, adhesion, and direct cell proliferation assays. In some of the experiments, RMS cells were exposed to vincristine (VCR) in the presence or absence of EPO to test whether EPO may impair the therapeutic effect of VCR. We report for a first time that functional EpoR is expressed in human RMS cell lines as well as by primary tumors from RMS patients. Furthermore, EpoR is detectably expressed in both embryonal and alveolar RMS subtypes. At the functional level, several human RMS cell lines responded to EPO stimulation by enhanced proliferation, chemotaxis, cell adhesion, and phosphorylation of MAPKp42/44 and AKT. Moreover, RMS cells became more resistant to VCR treatment in the presence of EPO. Our findings have important potential clinical implications, indicating that EPO supplementation in RMS patients may have the unwanted side effect of tumor progression. PMID:26412593

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

    PubMed

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

    2015-09-01

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

  14. Nonclinical evaluation of the potential for mast cell activation by an erythropoietin analog

    SciTech Connect

    Weaver, James L.

    2015-09-15

    The erythropoietin analog peginesatide was withdrawn from marketing due to unexpected severe anaphylactic reactions associated with administration of the multi-use formulation. The adverse events occurred rapidly following the first ever administration of the drug with most affected patients becoming symptomatic in less than 30 min. This is most consistent with an anaphylactoid reaction due to direct activation of mast cells. Laboratory evaluation was undertaken using rat peritoneal mast cells as the model system. Initial studies showed that high concentrations of the formulated drug as well as formulated vehicle alone could cause mast cell degranulation as measured by histamine release. The purified active drug was not able to cause histamine release whereas the vehicle filtrate and lab created drug vehicle were equally potent at causing histamine release. Individual formulations of vehicle leaving one component out showed that histamine release was due to phenol. Dose response studies with phenol showed a very sharp dose response curve that was similar in three buffer systems. Cellular analysis by flow cytometry showed that the histamine release was not due to cell death, and that changes in light scatter parameters consistent with degranulation were rapidly observed. Limited testing with primary human mast cells showed a similar dose response of histamine release with exposure to phenol. To provide in vivo confirmation, rats were injected with vehicle formulated with various concentrations of phenol via a jugular vein cannula. Significant release of histamine was detected in blood samples taken 2 min after dosing at the highest concentrations tested. - Highlights: • Peginesatide caused severe anaphylactoid reactions in 0.2% of patients. • Both formulated drug and vehicle cause degranulation of rat mast cells. • Phenol was identified as the vehicle component causing degranulation. • Human mast cells show similar dose response to phenol as rat mast cells

  15. Effect of short-term recombinant human erythropoietin therapy in the prevention of anemia of prematurity in very low birth weight neonates.

    PubMed

    Yasmeen, B H N; Chowdhury, M A K A; Hoque, M M; Hossain, M M; Jahan, R; Akhtar, S

    2012-12-01

    Premature infants especially those with birth weight < 1500 g suffer from Anaemia of prematurity (AOP) and associated problems. Erythropoietin therapy is a safe effective way to prevent and to treat anaemia of prematurity. To evaluate the effect of short-term administration of recombinant human erythropoietin (rHuEPO) with iron and folic acid in very low birth weight (VLBW) neonates in the prevention of anaemia of prematurity. A randomized controlled trial was carried out at Dhaka Shishu Hospital. Sixty preterm very low birth weight (PTVLBW) babies were enrolled in this study. Thirty were assigned to rHuEPO group and 30 as control. Baseline haematologic values were estimated before administration of rHuEPO. From day 7 of life rHuEPO-200 IU/kg/dose subcutaneously every alternate day for 2 weeks was administered to rHuEPO group. All infants in both groups have received oral iron, folic acid from day 14. Clinical and haematological assessment was done at 6 and 10 weeks of life. Baseline clinical characteristics and haematologic values were almost similar in both groups. This study has shown increase in haematological values (haemoglobin and haematocrit) and reduction in the number of blood transfusions during both the 1st and 2nd follow up in rHuEPO group in comparison to control group (p < 0.01). Short-term rHuEPO appears to be very effective in prevention of Anaemia of prematurity.

  16. Administrators: Nursing Home Administrator

    ERIC Educational Resources Information Center

    Kahl, Anne

    1976-01-01

    Responsibilities, skills needed, training needed, earnings, employment outlook, and sources of additional information are outlined for the administrator who holds the top management job in a nursing home. (JT)

  17. Absence of hematological side effects in acute and subacute nasal dosing of erythropoietin with a low content of sialic acid.

    PubMed

    Lagarto, Alicia; Bueno, Viviana; Guerra, Isbel; Valdés, Odalys; Couret, Micaela; López, Raisel; Vega, Yamile

    2011-09-01

    The use of human recombinant erythropoietin (EPO) as a neuroprotective agent is limited due to its hematological side effects. An erythropoietin along with a low content of sialic acid (rhEPOb), similar to that produced in the brain during hypoxia, may be used as a neuroprotective agent without risk of thrombotic events. The objective of this investigation was to assess the toxicological potential of a nasal formulation with rhEPOb in acute, subacute and nasal irritation assays in rats. Healthy Wistar rats (Cenp:Wistar) were used for the assays. In an irritation test, animals received 15 μl of rhEPOb into the right nostril. Rats were sacrificed after 24 h and slides of the nasal mucosa tissues were examined. Control and treated groups showed signs of a minimal irritation consisting of week edema and vascular congestion in all animals. In the acute toxicity test, the dose of 47,143 UI/kg was administered by nasal route. Hematological patterns, body weight, relative organ weight, and organ integrity were not affected by single dosing with rhEPOb. In the subacute toxicity test, Wistar rats of both sexes received 6,600 UI/kg/day for 14 days. The toxicological endpoints examined included animal body weight, food consumption, hematological and biochemical patterns, selected tissue weights, and histopathological examinations. An increase of lymphocytes was observed in males that was considered to reflect an immune response to treatment. Histopathological examination of organs and tissues did not reveal treatment-induced changes. The administration of rhEPOb at daily doses of 6,600 UI/kg during 14 days did not produce hematological side effects. These results suggest that rhEPOb could offer the same neuroprotection as EPO, without hematological side effects.

  18. Effects of early parenteral iron combined erythropoietin in preterm infants

    PubMed Central

    Qiao, Linxia; Tang, Qingya; Zhu, Wenying; Zhang, Haiyan; Zhu, Yuefang; Wang, Hua

    2017-01-01

    Abstract Backgroud: The aim of the study was to evaluate the effect of early parenteral iron supplementation combined erythropoietin for prevention of anemia in preterm infants. Methods: In total, 96 preterm infants were randomly assigned to 3 groups: a control group receiving standard parenteral nutrition (group 1: n = 31), an iron-supplemented group (group 2: IS, n = 33), and an iron-supplemented combined erythropoietin group (group 3: IS+EPO, n = 32). The primary objective was to assess hemoglobin (Hb) levels. The secondary objectives included assessment of red blood cell counts (RBC), mean cell volume (MCV), serum iron, ferritin, percentages of reticulocyte (RET), total iron binding capacity (TIBC) and oxidative stress, which was assessed by measuring plasma levels of malondialdehyde and superoxide dismutase at baseline and at 2 weeks. The blood routine indices including Hb, RBC, MCV, and percentages of RET were measured at corrected age of 1 and 3 months. Results: At 2 weeks of life, the percentages of reticulocyte in group 2 and group 3 were significantly higher than those in group 1 (2.1±0.4, 2.5±0.3, and 1.7±0.3, respectively, P < 0.001, P<0.001), whereas TIBC were significantly lower than those in group 1 (36.7±4.6, 36.0±4.7, and 41.6 ± 5.2 respectively, P = 0.011, P = 0.006). There were no significant differences in RBC counts, the levels of hemoglobin, ferritin, malondialdehyde, and superoxide dismutase among the 3 groups at 2weeks of life. RBC, Hb, MCV, body weight, body length, and head circumference at a corrected age of 1 month did not differ among 3 groups. At corrected age of 3months, more infants in the control group had abnormal Hb and MCV levels (Hb levels: 114.3 ± 21.3, 123.7 ± 31.6, and 125.1 ± 21.2, P = 0.021, P = 0.034, respectively; MCV: 74.1 ± 3.5, 78.3 ± 4.7 and 79.1 ± 5.2, P = 0.017, P = 0.012, respectively), whereas cases of oral iron, cases of breastfeeding

  19. No response to recombinant human erythropoietin therapy in patients with congenital dyserythropoietic anemia type I.

    PubMed

    Tamary, H; Shalev, H; Pinsk, V; Zoldan, M; Zaizov, R

    1999-01-01

    Congenital dyserythropoietic anemia (CDA) type I is a rare inherited bone marrow disorder characterized by moderate to severe macrocytic anemia with pathognomonic cytopathology of nucleated red blood cells. Previous studies have suggested that serum erythropoietin levels in affected patients are lower than expected for the degree of anemia. An earlier study demonstrated a substantial increase in the number of CFU-E in CDA type I pattern on addition of exogenous erythropoietin. The present study reports on the response to recombinant human erythropoietin in 8 patients with CDA type I. Eighteen weeks of treatment, starting at 300 IU/kg twice a week and gradually increasing to 500 IU/kg three times a week, did not have a substantial effect on the mean hemoglobin value. These results indicate that recombinant human erythropoietin (rHuEpo) is not beneficial to patients with CDA type I and that the relatively low levels of serum erythropoietin probably play no major role in the pathogenesis of the disease.

  20. The hematopoietic growth factor "erythropoietin" enhances the therapeutic effect of mesenchymal stem cells in Alzheimer's disease.

    PubMed

    Khairallah, M I; Kassem, L A; Yassin, N A; El Din, M A Gamal; Zekri, M; Attia, M

    2014-01-01

    Alzheimer's disease is a neurodegenerative disorder clinically characterized by cognitive dysfunction and by deposition of amyloid plaques, neurofibrillary tangles in the brain. The study investigated the therapeutic effect of combined mesenchymal stem cells and erythropoietin on Alzheimer's disease. Five groups of mice were used: control group, Alzheimer's disease was induced in four groups by a single intraperitoneal injection of 0.8 mg kg(-1) lipopolysaccharide and divided as follows: Alzheimer's disease group, mesenchymal stem cells treated group by injecting mesenchymal stem cells into the tail vein (2 x 10(6) cells), erythropoietin treated group (40 microg kg(-1) b.wt.) injected intraperitoneally 3 times/week for 5 weeks and mesenchymal stem cells and erythropoietin treated group. Locomotor activity and memory were tested using open field and Y-maze. Histological, histochemical, immunohistochemical studies, morphometric measurements were examined in brain sections of all groups. Choline transferase activity, brain derived neurotrophic factor expression and mitochondrial swellings were assessed in cerebral specimens. Lipopolysaccharide decreased locomotor activity, memory, choline transferase activity and brain derived neurotrophic factor. It increased mitochondrial swelling, apoptotic index and amyloid deposition. Combined mesenchymal stem cells and erythropoietin markedly improved all these parameters. This study proved the effective role of mesenchymal stem cells in relieving Alzheimer's disease symptoms and manifestations; it highlighted the important role of erythropoietin in the treatment of Alzheimer's disease.

  1. Nutritional assessment in anemic hemodialysis patients treated with recombinant human erythropoietin.

    PubMed

    Bárány, P; Pettersson, E; Ahlberg, M; Hultman, E; Bergström, J

    1991-06-01

    Nutritional status was assessed in 25 anemic hemodialysis patients before and during erythropoietin treatment. Nutritional assessment included regular blood chemistry determinations, anthropometric measurements, analysis of protein content in skeletal muscle, and estimation of daily protein intake from protein catabolic rate determinations (using urea kinetic modelling) and dialysis efficiency for urea. These measurements were done immediately prior to erythropoietin treatment, after anemia correction and after one year of maintenance erythropoietin treatment. Both relative body weights and subcutaneous fat stores were low at the start, but increased significantly (p less than 0.05) during the study. Sixteen of the 25 patients gained weight and eight patients lost weight. The patients with weight gain had at the start of the study low weight indices (body weight 89.9 +/- 7.6% of ideal body weight, body mass index 20.6 +/- 1.6), significantly (p less than 0.005) lower than the patients with weight loss. Although protein malnutrition was not obvious from arm anthropometrics, alkali soluble protein/DNA ratio or from serum albumin determinations, ASP/DNA ratio, increased in three of five patients investigated after one year on erythropoietin treatment. Neither protein catabolic rate nor dialysis efficiency changed significantly during the study. We conclude that anemia correction with erythropoietin has a positive effect on malnutrition in hemodialysis patients. In patients with underweight, an adjustment of fat stores was initially observed, followed possibly by an improvement in muscle protein content.

  2. Cell-type-specific and hypoxia-inducible expression of the human erythropoietin gene in transgenic mice

    SciTech Connect

    Semenza, G.L.; Nejfelt, M.K.; Gearhart, J.D.; Antonarakis, S.E. ); Koury, S.T. )

    1991-10-01

    Synthesis of erythropoietin, the primary humoral regulator or erythropoiesis, in liver and kidney is inducible by anemia or hypoxia. Analysis of human erythropoietin gene expression in transgenic mice revealed that sequences located 6-14 kilobases 5{prime} to the gene direct expression to the kidney, whereas sequences within the immediate 3{prime}-flanking region control hepatocyte-specific expression. Human erythropoietin transcription initiation sites were differentially utilized in liver and kidney. Inducible transgene expression was precisely targeted to peritubular interstitial cells in the renal cortex that synthesize endogenous mouse erythropoietin. These studies demonstrate that multiple erythropoietin gene regulatory elements control cello-type-specific expression and inducibility by a fundamental physiologic stimulus, hypoxia.

  3. Hepatoprotective effects of erythropoietin on D-galactosamine/lipopolysaccharide-induced fulminant hepatic failure in mice.

    PubMed

    Yang, Xue-Fei; He, Yi; Li, Hai-Yuan; Liu, Xin; Chen, Huan; Liu, Jian-Bang; Ji, Wen-Jun; Wang, Bing; Chen, Li-Na

    2014-07-01

    Fulminant hepatic failure is a severe clinical syndrome associated with a high rate of patient mortality. Recent studies have shown that in addition to its hematopoietic effect, erythropoietin (EPO) has multiple protective effects and exhibits antiapoptotic, antioxidant and anti-inflammatory activities. The present study aimed to determine the hepatoprotective effect of EPO and to elucidate the underlying mechanisms using a D-galactosamine (D-GalN)/lipopolysaccharide (LPS)-induced model of acute liver injury. Experimental groups of mice were administered with various doses of EPO (1,000, 3,000 or 10,000 U/kg, intraperitoneal) once per day for 3 days, prior to injection with D-GalN (700 mg/kg)/LPS (10 µg/kg). Mice were sacrificed 8 h after treatment with D‑GalN/LPS. Liver function and histopathology, malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH‑Px) activities and EPO receptor (EPOR) and phosphatidylinositol 3-kinase (PI3K) mRNA expression were evaluated. D-GalN/LPS administration markedly induced liver injury, as evidenced by elevated levels of serum aminotransferases, as well as histopathological changes. Compared with the D-GalN/LPS group, pretreatment with EPO significantly decreased the levels of aspartate aminotransferase, alanine aminotransferase and MDA, and increased the activities of SOD and GSH-Px. Furthermore, the protective effects of EPO were paralleled by an upregulation in the mRNA expression of EPOR and PI3K. These data suggest that EPO can ameliorate D-GalN/LPS-induced acute liver injury by reducing oxidative stress and upregulating the mRNA expression of EPOR and PI3K.

  4. Discovery and Characterization of Nonpeptidyl Agonists of the Tissue-Protective Erythropoietin Receptor

    PubMed Central

    Church, Timothy J.; Leonoudakis, Dmitri; Lariosa-Willingham, Karen; Frigon, Normand L.; Tettenborn, Connie S.; Spencer, Jeffrey R.; Punnonen, Juha

    2015-01-01

    Erythropoietin (EPO) and its receptor are expressed in a wide variety of tissues, including the central nervous system. Local expression of both EPO and its receptor is upregulated upon injury or stress and plays a role in tissue homeostasis and cytoprotection. High-dose systemic administration or local injection of recombinant human EPO has demonstrated encouraging results in several models of tissue protection and organ injury, while poor tissue availability of the protein limits its efficacy. Here, we describe the discovery and characterization of the nonpeptidyl compound STS-E412 (2-[2-(4-chlorophenoxy)ethoxy]-5,7-dimethyl-[1,2,4]triazolo[1,5-a]pyrimidine), which selectively activates the tissue-protective EPO receptor, comprising an EPO receptor subunit (EPOR) and the common β-chain (CD131). STS-E412 triggered EPO receptor phosphorylation in human neuronal cells. STS-E412 also increased phosphorylation of EPOR, CD131, and the EPO-associated signaling molecules JAK2 and AKT in HEK293 transfectants expressing EPOR and CD131. At low nanomolar concentrations, STS-E412 provided EPO-like cytoprotective effects in primary neuronal cells and renal proximal tubular epithelial cells. The receptor selectivity of STS-E412 was confirmed by a lack of phosphorylation of the EPOR/EPOR homodimer, lack of activity in off-target selectivity screening, and lack of functional effects in erythroleukemia cell line TF-1 and CD34+ progenitor cells. Permeability through artificial membranes and Caco-2 cell monolayers in vitro and penetrance across the blood-brain barrier in vivo suggest potential for central nervous system availability of the compound. To our knowledge, STS-E412 is the first nonpeptidyl, selective activator of the tissue-protective EPOR/CD131 receptor. Further evaluation of the potential of STS-E412 in central nervous system diseases and organ protection is warranted. PMID:26018904

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

    PubMed

    Martin, L; Ashenden, M; Bejder, J; Hoffmann, M; Nordsborg, N; Karstoft, K; Morkeberg, J; Sharpe, K; Lasne, F; Marchand, A

    2016-11-01

    To minimize the chances of being caught after doping with recombinant human erythropoietins (rhEPO), athletes have turned to new practices using micro-doses and excess fluid ingestion to accelerate elimination and decrease the probability of detection. Our objective was to test the sensitivity of detection by validated methods (IEF: isoelectric focusing; SDS-PAGE: sodium dodecyl sulfate polyacrylamide gel electrophoresis) when such practices are used. First, after a three-week rhEPO boost period and 10 days of wash out, detection of a single 900 IU micro-dose of Eprex® was evaluated in healthy male 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 protocol was then performed with a single injection of a micro-dose of rhEPO (500 IU or 900 IU), without a prior rhEPO boost. In addition, urine and plasma samples were also collected 15 and 20 h post rhEPO administration. Once again drinking water did not affect the rate of detection. Urine appeared a better matrix to detect micro-doses after 10 h, enabling between 92% and 100% of identification at that time. The rate of identification decreased rapidly thereafter, in particular for the 500 IU micro-dose. However IEF analysis still resulted in 71% identification of rhEPO in urine after 20 h. These results could help to define a better strategy for controlling and identifying athletes using rhEPO micro-doses. Copyright © 2016 John Wiley & Sons, Ltd.

  6. Recombinant human erythropoietin therapy in critically ill patients: a dose-response study [ISRCTN48523317

    PubMed Central

    Georgopoulos, Dimitris; Matamis, Dimitris; Routsi, Christina; Michalopoulos, Argiris; Maggina, Nina; Dimopoulos, George; Zakynthinos, Epaminondas; Nakos, George; Thomopoulos, George; Mandragos, Kostas; Maniatis, Alice

    2005-01-01

    Introduction The aim of this study was to assess the efficacy of two dosing schedules of recombinant human erythropoietin (rHuEPO) in increasing haematocrit (Hct) and haemoglobin (Hb) and reducing exposure to allogeneic red blood cell (RBC) transfusion in critically ill patients. Method This was a prospective, randomized, multicentre trial. A total of 13 intensive care units participated, and a total of 148 patients who met eligibility criteria were enrolled. Patients were randomly assigned to receive intravenous iron saccharate alone (control group), intravenous iron saccharate and subcutaneous rHuEPO 40,000 units once per week (group A), or intravenous iron saccharate and subcutaneous rHuEPO 40,000 units three times per week (group B). rHuEPO was given for a minimum of 2 weeks or until discharge from the intensive care unit or death. The maximum duration of therapy was 3 weeks. Results The cumulative number of RBC units transfused, the average numbers of RBC units transfused per patient and per transfused patient, the average volume of RBCs transfused per day, and the percentage of transfused patients were significantly higher in the control group than in groups A and B. No significant difference was observed between group A and B. The mean increases in Hct and Hb from baseline to final measurement were significantly greater in group B than in the control group. The mean increase in Hct was significantly greater in group B than in group A. The mean increase in Hct in group A was significantly greater than that in control individuals, whereas the mean increase in Hb did not differ significantly between the control group and group A. Conclusion Administration of rHuEPO to critically ill patients significantly reduced the need for RBC transfusion. The magnitude of the reduction did not differ between the two dosing schedules, although there was a dose response for Hct and Hb to rHuEPO in these patients. PMID:16277712

  7. Erythropoietin elevates VO2,max but not voluntary wheel running in mice.

    PubMed

    Kolb, E M; Kelly, S A; Middleton, K M; Sermsakdi, L S; Chappell, M A; Garland, T

    2010-02-01

    Voluntary activity is a complex trait, comprising both behavioral (motivation, reward) and anatomical/physiological (ability) elements. In the present study, oxygen transport was investigated as a possible limitation to further increases in running by four replicate lines of mice that have been selectively bred for high voluntary wheel running and have reached an apparent selection limit. To increase oxygen transport capacity, erythrocyte density was elevated by the administration of an erythropoietin (EPO) analogue. Mice were given two EPO injections, two days apart, at one of two dose levels (100 or 300 microg kg(-1)). Hemoglobin concentration ([Hb]), maximal aerobic capacity during forced treadmill exercise (VO2,max) and voluntary wheel running were measured. [Hb] did not differ between high runner (HR) and non-selected control (C) lines without EPO treatment. Both doses of EPO significantly (P<0.0001) increased [Hb] as compared with sham-injected animals, with no difference in [Hb] between the 100 microg kg(-1) and 300 microg kg(-1) dose levels (overall mean of 4.5 g dl(-1) increase). EPO treatment significantly increased VO2,max by approximately 5% in both the HR and C lines, with no dosexline type interaction. However, wheel running (revolutions per day) did not increase with EPO treatment in either the HR or C lines, and in fact significantly decreased at the higher dose in both line types. These results suggest that neither [Hb] per se nor VO2,max is limiting voluntary wheel running in the HR lines. Moreover, we hypothesize that the decrease in wheel running at the higher dose of EPO may reflect direct action on the reward pathway of the brain.

  8. Grafted Neural Precursors Integrate Into Mouse Striatum, Differentiate and Promote Recovery of Function Through Release of Erythropoietin in MPTP-Treated Mice

    PubMed Central

    Giallongo, Toniella; Viaggi, Cristina; Gombalova, Zuzana; Latorre, Elisa; Mazza, Massimiliano; Vaglini, Francesca; Di Giulio, Anna Maria; Gorio, Alfredo

    2016-01-01

    Erythropoietin-releasing neural precursor cells (Er-NPCs) are a subclass of subventricular zone-derived neural progenitors, capable of surviving for 6 hr after death of donor. They present higher neural differentiation. Here, Er-NPCs were studied in animal model of Parkinson’s disease. Dopaminergic degeneration was caused by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine intraperitoneal administration in C57BL/6 mice. The loss of function was evaluated by specific behavioral tests. Er-NPCs (2.5 × 105) expressing the green fluorescent protein were administered by stereotaxic injection unilaterally in the left striatum. At the end of observational research period (2 weeks), most of the transplanted Er-NPCs were located in the striatum, while several had migrated ventrally and caudally from the injection site, up to ipsilateral and contralateral substantia nigra. Most of transplanted cells had differentiated into dopaminergic, cholinergic, or GABAergic neurons. Er-NPCs administration also promoted a rapid functional improvement that was already evident at the third day after cells administration. This was accompanied by enhanced survival of nigral neurons. These effects were likely promoted by Er-NPCs-released erythropoietin (EPO), since the injection of Er-NPCs in association with anti-EPO or anti-EPOR antibodies had completely neutralized the recovery of function. In addition, intrastriatal administration of recombinant EPO mimics the effects of Er-NPCs. We suggest that Er-NPCs, and cells with similar properties, may represent good candidates for cellular therapy in neurodegenerative disorders of this kind. PMID:27789613

  9. Effects of erythropoietin in skin wound healing are dose related.

    PubMed

    Sorg, Heiko; Krueger, Christian; Schulz, Torsten; Menger, Michael D; Schmitz, Frank; Vollmar, Brigitte

    2009-09-01

    The hematopoietic growth factor erythropoietin (EPO) attracts attention due to its all-tissue-protective pleiotropic properties. We studied the effect of EPO on dermal regeneration using intravital microscopy in a model of full dermal thickness wounds in the skin-fold chamber of hairless mice. Animals received repetitive low doses or high doses of EPO (RLD-EPO or RHD-EPO) or a single high dose of EPO (SHD-EPO). SHD-EPO accelerated wound epithelialization, reduced wound cellularity, and induced maturation of newly formed microvascular networks. In contrast, RHD-EPO impaired the healing process, as indicated by delayed epithelialization, high wound cellularity, and lack of maturation of microvascular networks. Also, RHD-EPO caused an excessive erythrocyte mass and rheological malfunction, further deteriorating vessel and tissue maturation. Moreover, RHD-EPO altered fibroblast and keratinocyte migration in vitro, while both cell types exposed to RLD-EPO, and, in particular, to SHD-EPO showed accelerated wound scratch closure. In summary, our data show that a single application of a high dose of EPO accelerates and improves skin wound healing.

  10. Low dose erythropoietin stimulates bone healing in mice.

    PubMed

    Garcia, P; Speidel, V; Scheuer, C; Laschke, M W; Holstein, J H; Histing, T; Pohlemann, T; Menger, M D

    2011-02-01

    Beyond its classical role in regulation of erythropoiesis, erythropoietin (EPO) has been shown to exert protective and regenerative actions in a variety of non-hematopoietic tissues. However, little is known about potential actions in bone regeneration. To analyze fracture healing in mice, a femoral 0.25 mm osteotomy gap was stabilized with a pin-clip technique. Animals were treated with 500 U EPO/kg bw per day or with vehicle only. After 2 and 5 weeks, fracture healing was analyzed biomechanically, radiologically and histologically. Expression of PCNA and NFκB was examined by Western blot analysis. Vascularization was analyzed by immunohistochemical staining of PECAM-1. Circulating endothelial progenitor cells were measured by flow-cytometry. Herein, we demonstrate that EPO-treatment significantly accelerates bone healing in mice. This is indicated by a significantly greater biomechanical stiffness and a higher radiological density of the periosteal callus at 2 and 5 weeks after fracture and stabilization. Histological analysis demonstrated significantly more bone and less cartilage and fibrous tissue in the periosteal callus. Endosteal vascularization was significantly increased in EPO-treated animals when compared to controls. The number of circulating endothelial progenitor cells was significantly greater in EPO-treated animals. The herein shown acceleration of healing by EPO may represent a promising novel treatment strategy for fractures with delayed healing and non-union formation.

  11. Neurite outgrowth on cultured spiral ganglion neurons induced by erythropoietin.

    PubMed

    Berkingali, Nurdanat; Warnecke, Athanasia; Gomes, Priya; Paasche, Gerrit; Tack, Jan; Lenarz, Thomas; Stöver, Timo

    2008-09-01

    The morphological correlate of deafness is the loss of hair cells with subsequent degeneration of spiral ganglion neurons (SGN). Neurotrophic factors have a neuroprotective effect, and especially brain-derived neurotrophic factor (BDNF) has been demonstrated to protect SGN in vitro and after ototoxic trauma in vivo. Erythropoietin (EPO) attenuates hair cell loss in rat cochlea explants that were treated with gentamycin. Recently, it has also been shown that EPO reduces the apoptose rate in hippocampal neurons. Therefore, the aim of the study was to examine the effects of EPO on SGN in vitro. Spiral ganglion cells were isolated from neonatal rats and cultured for 48 h in serum-free medium supplemented with EPO and/or BDNF. Results showed that survival rates of SGN were not significantly improved when cultivated with EPO alone. Also, EPO did not further increase BDNF-induced survival of SGN. However, significant elongation of neurites was determined when SGN were cultivated with EPO alone. Even though a less than additive effect was observed, combined treatment with BDNF and EPO led to a significant elongation of neurites when compared to individual treatment with BDNF or EPO. It can be concluded that EPO induces neurite outgrowth rather than promoting survival. Thus, EPO presents as an interesting candidate to enhance and modulate the regenerative effect of BDNF on SGN.

  12. Topical erythropoietin promotes wound repair in diabetic rats.

    PubMed

    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.

  13. Local erythropoietin signaling enhances regeneration in peripheral axons.

    PubMed

    Toth, C; Martinez, J A; Liu, W Q; Diggle, J; Guo, G F; Ramji, N; Mi, R; Hoke, A; Zochodne, D W

    2008-06-23

    Erythropoietin (EPO) and its receptor (EPO-R), mediate neuroprotection from axonopathy and apoptosis in the peripheral nervous system (PNS). We examined the impact and potential mechanisms of local EPO signaling on regenerating PNS axons in vivo and in vitro. As a consequence of injury, peripheral nerve axons and DRG neurons have a marked increase in the expression of EPO and EPO-R. Local delivery of EPO via conduit over 2 weeks to rat sciatic nerve following crush injury increased the density and maturity of regenerating myelinated axons growing distally from the crush site. In addition, EPO also rescued retrograde degeneration and atrophy of axons. EPO substantially increased the density and intensity of calcitonin gene-related peptide (CGRP) expression within outgrowing axons. Behavioral improvements in sensorimotor function also occurred in rats exposed to near nerve EPO delivery. EPO delivery led to decreased nuclear factor kappaB (NFkB) activation but increased phosphorylation of Akt and STAT3 within nerve and dorsal root ganglia neurons indicating rescue from an injury phenotype. Spinal cord explant studies also demonstrated a similar dose-dependent effect of EPO upon motor axonal outgrowth. Local EPO signaling enhances regenerating peripheral nervous system axons in addition to its known neuroprotection. Exogenous EPO may have a therapeutic role in a large number of peripheral nerve diseases through its impact on regeneration.

  14. Hypoxia Signaling Cascade for Erythropoietin Production in Hepatocytes.

    PubMed

    Tojo, Yutaka; Sekine, Hiroki; Hirano, Ikuo; Pan, Xiaoqing; Souma, Tomokazu; Tsujita, Tadayuki; Kawaguchi, Shin-ichi; Takeda, Norihiko; Takeda, Kotaro; Fong, Guo-Hua; Dan, Takashi; Ichinose, Masakazu; Miyata, Toshio; Yamamoto, Masayuki; Suzuki, Norio

    2015-08-01

    Erythropoietin (Epo) is produced in the kidney and liver in a hypoxia-inducible manner via the activation of hypoxia-inducible transcription factors (HIFs) to maintain oxygen homeostasis. Accelerating Epo production in hepatocytes is one plausible therapeutic strategy for treating anemia caused by kidney diseases. To elucidate the regulatory mechanisms of hepatic Epo production, we analyzed mouse lines harboring liver-specific deletions of genes encoding HIF-prolyl-hydroxylase isoforms (PHD1, PHD2, and PHD3) that mediate the inactivation of HIF1α and HIF2α under normal oxygen conditions. The loss of all PHD isoforms results in both polycythemia, which is caused by Epo overproduction, and fatty livers. We found that deleting any combination of two PHD isoforms induces polycythemia without steatosis complications, whereas the deletion of a single isoform induces no apparent phenotype. Polycythemia is prevented by the loss of either HIF2α or the hepatocyte-specific Epo gene enhancer (EpoHE). Chromatin analyses show that the histones around EpoHE dissociate from the nucleosome structure after HIF2α activation. HIF2α also induces the expression of HIF3α, which is involved in the attenuation of Epo production. These results demonstrate that the total amount of PHD activity is more important than the specific function of each isoform for hepatic Epo expression regulated by a PHD-HIF2α-EpoHE cascade in vivo.

  15. Erythropoietin-loaded oligochitosan nanoparticles for treatment of periventricular leukomalacia.

    PubMed

    Wang, Ting; Hu, Yan; Leach, Michelle K; Zhang, Long; Yang, Wenjing; Jiang, Li; Feng, Zhang-Qi; He, Nongyue

    2012-01-17

    In this study, a single intraperitoneal injection of erythropoietin (EPO) loaded oligochitosan nanoparticles (epo-NPs) (average diameter 266 nm) was investigated as a treatment for periventricular leukomalacia (PVL). Nanoparticles were fabricated using a gelation technology process. PVL rats models were prepared to examine the therapeutic efficacy of epo-NPs and analyze the mechanism by which epo-NPs protect white matter. The metabolization of epo-NPs in the liver was also investigated. The pathology and behavioral data show that this single injection of a low quantity of epo-NPs had an excellent therapeutic effect on the rat model of PVL. The EPO release curve in phosphate buffered saline solution was a good fit with the zero-order kinetics distribution and was maintained at around 25% in 48 h. In vivo experiments demonstrated that 50 IU/kg epo-NPs had the same effect as a 5000 IU/kg direct injection of free EPO. Nanoparticles prolonged the time course of EPO metabolization in the liver and the stable release of EPO from the nanoparticles kept the plasma concentration of EPO at around 100 IU/ml during the 8-12h post-injection. Therefore, we suggest that oligochitosan based nanoparticles are an effective vehicle for drug delivery.

  16. Hepatic erythropoietin response in cirrhosis. A contemporary review.

    PubMed

    Risør, Louise Madeleine; Fenger, Mogens; Olsen, Niels Vidiendal; Møller, Søren

    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-derived EPO. Elevated circulating EPO has been reported in a number of diseases, but data from cirrhotic patients are sparse and the level of plasma EPO in patients with cirrhosis is controversial. Cirrhosis is characterized by liver fibrosis, hepatic dysfunction and the release of proinflammatory cytokines, 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 feedback mechanisms may explain a potential insufficient EPO response in end-stage cirrhosis. Finally, the question remains as to whether a potential increase in EPO production in certain stages of cirrhosis originates from the kidney or liver. This paper aims to review contemporary aspects of EPO relating to chronic liver disease.

  17. Oxygen-dependent Regulation of Erythropoietin Receptor Turnover and Signaling*

    PubMed Central

    Heir, Pardeep; Srikumar, Tharan; Bikopoulos, George; Bunda, Severa; Poon, Betty P.; Lee, Jeffrey E.; Raught, Brian; Ohh, Michael

    2016-01-01

    von Hippel-Lindau (VHL) disease is a rare familial cancer predisposition syndrome caused by a loss or mutation in a single gene, VHL, but it exhibits a wide phenotypic variability that can be categorized into distinct subtypes. The phenotypic variability has been largely argued to be attributable to the extent of deregulation of the α subunit of hypoxia-inducible factor α, a well established target of VHL E3 ubiquitin ligase, ECV (Elongins/Cul2/VHL). Here, we show that erythropoietin receptor (EPOR) is hydroxylated on proline 419 and 426 via prolyl hydroxylase 3. EPOR hydroxylation is required for binding to the β domain of VHL and polyubiquitylation via ECV, leading to increased EPOR turnover. In addition, several type-specific VHL disease-causing mutants, including those that have retained proper binding and regulation of hypoxia-inducible factor α, showed a severe defect in binding prolyl hydroxylated EPOR peptides. These results identify EPOR as the second bona fide hydroxylation-dependent substrate of VHL that potentially influences oxygen homeostasis and contributes to the complex genotype-phenotype correlation in VHL disease. PMID:26846855

  18. Erythropoietin, forkhead proteins, and oxidative injury: biomarkers and biology.

    PubMed

    Maiese, Kenneth; Hou, Jinling; Chong, Zhao Zhong; Shang, Yan Chen

    2009-10-02

    Oxidative stress significantly impacts multiple cellular pathways that can lead to the initiation and progression of varied disorders throughout the body. It therefore becomes imperative to elucidate the components and function of novel therapeutic strategies against oxidative stress to further clinical diagnosis and care. In particular, both the growth factor and cytokine erythropoietin (EPO), and members of the mammalian forkhead transcription factors of the O class (FoxOs), may offer the greatest promise for new treatment regimens, since these agents and the cellular pathways they oversee cover a range of critical functions that directly influence progenitor cell development, cell survival and degeneration, metabolism, immune function, and cancer cell invasion. Furthermore, both EPO and FoxOs function not only as therapeutic targets, but also as biomarkers of disease onset and progression, since their cellular pathways are closely linked and overlap with several unique signal transduction pathways. Yet, EPO and FoxOs may sometimes have unexpected and undesirable effects that can raise caution for these agents and warrant further investigations. Here we present the exciting as well as the complex role that EPO and FoxOs possess to uncover the benefits as well as the risks of these agents for cell biology and clinical care in processes that range from stem cell development to uncontrolled cellular proliferation.

  19. Erythropoietin elevation in the chronically hyperglycemic fetal lamb

    SciTech Connect

    Philipps, A.F. Widness, J.A.; Garcia, J.F.; Raye, J.R.; Swartz, R.

    1982-05-01

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

  20. ERYTHROPOIETIN: ELUCIDATING NEW CELLULAR TARGETS THAT BROADEN THERAPEUTIC STRATEGIES

    PubMed Central

    Maiese, Kenneth; Chong, Zhao Zhong; Li, Faqi; Shang, Yan Chen

    2008-01-01

    Given that erythropoietin (EPO) is no longer believed to have exclusive biological activity in the hematopoietic system, EPO is now considered to have applicability in a variety of nervous system disorders that can overlap with vascular disease, metabolic impairments, and immune system function. As a result, EPO may offer efficacy for a broad number of disorders that involve Alzheimer’s disease, cardiac insufficiency, stroke, trauma, and diabetic complications. During a number of clinical conditions, EPO is robust and can prevent metabolic compromise, neuronal and vascular degeneration, and inflammatory cell activation. Yet, use of EPO is not without its considerations especially in light of frequent concerns that may compromise clinical care. Recent work has elucidated a number of novel cellular pathways governed by EPO that can open new avenues to avert deleterious effects of this agent and offer previously unrecognized perspectives for therapeutic strategies. Obtaining greater insight into the role of EPO in the nervous system and elucidating its unique cellular pathways may provide greater cellular viability not only in the nervous system but also throughout the body. PMID:18396368

  1. Erythropoietin regulates Treg cells in asthma through TGFβ receptor signaling.

    PubMed

    Wan, Guoshi; Wei, Bing

    2015-01-01

    Asthma is a chronic inflammatory disorder of the airways, the development of which is suppressed by regulatory T cells (Treg). Erythropoietin (EPO) is originally defined as a hematopoietic growth factor. Recently, the anti-inflammatory effects of EPO in asthma have been acknowledged. However, the underlying mechanisms remain ill-defined. Here, we showed that EPO treatment significantly reduced the severity of an ovalbumin (OVA)-induced asthma in mice, seemingly through promoting Foxp3-mediated activation of Treg cells in OVA-treated mouse lung. The activation of Treg cells resulted from increases in transforming growth factor β1 (TGFβ1), which were mainly produced by M2 macrophages (M2M). In vitro, Co-culture with M2M increased Foxp3 levels in Treg cells and the Treg cell number, in a TGFβ receptor signaling dependent manner. Moreover, elimination of macrophages abolished the therapeutic effects of EPO in vivo. Together, our data suggest that EPO may increase M2M, which activate Treg cells through TGFβ receptor signaling to mitigate the severity of asthma.

  2. Erythropoietin, Forkhead Proteins, and Oxidative Injury: Biomarkers and Biology

    PubMed Central

    Maiese, Kenneth; Hou, Jinling; Chong, Zhao Zhong; Shang, Yan Chen

    2009-01-01

    Oxidative stress significantly impacts multiple cellular pathways that can lead to the initiation and progression of varied disorders throughout the body. It therefore becomes imperative to elucidate the components and function of novel therapeutic strategies against oxidative stress to further clinical diagnosis and care. In particular, both the growth factor and cytokine erythropoietin (EPO), and members of the mammalian forkhead transcription factors of the O class (FoxOs), may offer the greatest promise for new treatment regimens, since these agents and the cellular pathways they oversee cover a range of critical functions that directly influence progenitor cell development, cell survival and degeneration, metabolism, immune function, and cancer cell invasion. Furthermore, both EPO and FoxOs function not only as therapeutic targets, but also as biomarkers of disease onset and progression, since their cellular pathways are closely linked and overlap with several unique signal transduction pathways. Yet, EPO and FoxOs may sometimes have unexpected and undesirable effects that can raise caution for these agents and warrant further investigations. Here we present the exciting as well as the complex role that EPO and FoxOs possess to uncover the benefits as well as the risks of these agents for cell biology and clinical care in processes that range from stem cell development to uncontrolled cellular proliferation. PMID:19802503

  3. A mouse model for an erythropoietin-deficiency anemia.

    PubMed

    Zeigler, Brandon M; Vajdos, Janis; Qin, Wenning; Loverro, Linda; Niss, Knut

    2010-01-01

    In mammals, the production of red blood cells is tightly regulated by the growth factor erythropoietin (EPO). Mice lacking a functional Epo gene are embryonic lethal, and studying erythropoiesis in EPO-deficient adult animals has therefore been limited. In order to obtain a preclinical model for an EPO-deficient anemia, we developed a mouse in which Epo can be silenced by Cre recombinase. After induction of Cre activity, Epo(KO/flox) mice experience a significant reduction of serum EPO levels and consequently develop a chronic, normocytic and normochromic anemia. Furthermore, compared with wild-type mice, Epo expression in Epo(KO/flox) mice is dramatically reduced in the kidney, and expression of a well-known target gene of EPO signaling, Bcl2l1, is reduced in the bone marrow. These observations are similar to the clinical display of anemia in patients with chronic kidney disease. In addition, during stress-induced erythropoiesis these mice display the same recovery rate as their heterozygous counterparts. Taken together, these results demonstrate that this model can serve as a valuable preclinical model for the anemia of EPO deficiency, as well as a tool for the study of stress-induced erythropoiesis during limiting conditions of EPO.

  4. Study on the inflammatory intervention of erythropoietin on NEC

    PubMed Central

    QI, WEIBIN; SHEN, QIONG; ZHANG, LIN; HAN, LI-PING; WANG, SUMIN

    2016-01-01

    The aim of this study was to investigate the effect of erythropoietin (EPO) on the inflammatory response and the mechanism analysis of the Τoll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) signaling pathway of NEC. A total of 94 patients with necrotizing enterocolitis (NEC) were randomly divided into the control (42 cases) and observation (52 cases) groups, The control group received the standard medical treatment plan, whereas for the observation group this treatment plan was combined with the application of recombinant EPO for intramuscular injection treatment. The clinical effect was subsequently compared. The results showed that the complication and death rates in the observation group were significantly lower than those in the control group with statistically significant differences (P<0.05). Following treatments, the levels of tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 in the observation group were significantly lower than those in the control group. The expression levels of mRNA of TLR4 and NF-κB in the observation group were significantly lower than those in the control group, with statistically significant differences (P<0.05). In summary, EPO was able to reduce the levels of inflammatory response of TNF-α and IL-6 through the TLR4/NF-κB signaling pathway, and improve the NEC, thus providing a basis for the clinical treatment of NEC. PMID:27284304

  5. The non-haematopoietic biological effects of erythropoietin.

    PubMed

    Arcasoy, Murat O

    2008-04-01

    In the haematopoietic system, the principal function of erythropoietin (Epo) is the regulation of red blood cell production, mediated by its specific cell surface receptor (EpoR). Following the cloning of the Epo gene (EPO) and characterization of the selective haematopoietic action of Epo in erythroid lineage cells, recombinant Epo forms (epoetin-alfa, epoetin-beta and the long-acting analogue darbepoetin-alfa) have been widely used for treatment of anaemia in chronic kidney disease and chemotherapy-induced anaemia in cancer patients. Ubiquitous EpoR expression in non-erythroid cells has been associated with the discovery of diverse biological functions for Epo in non-haematopoietic tissues. During development, Epo-EpoR signalling is required not only for fetal liver erythropoiesis, but also for embryonic angiogenesis and brain development. A series of recent studies suggest that endogenous Epo-EpoR signalling contributes to wound healing responses, physiological and pathological angiogenesis, and the body's innate response to injury in the brain and heart. Epo and its novel derivatives have emerged as major tissue-protective cytokines that are being investigated in the first human studies involving neurological and cardiovascular diseases. This review focuses on the scientific evidence documenting the biological effects of Epo in non-haematopoietic tissues and discusses potential future applications of Epo and its derivatives in the clinic.

  6. Erythropoietin enhances hippocampal long-term potentiation and memory

    PubMed Central

    Adamcio, Bartosz; Sargin, Derya; Stradomska, Alicja; Medrihan, Lucian; Gertler, Christoph; Theis, Fabian; Zhang, Mingyue; Müller, Michael; Hassouna, Imam; Hannke, Kathrin; Sperling, Swetlana; Radyushkin, Konstantin; El-Kordi, Ahmed; Schulze, Lizzy; Ronnenberg, Anja; Wolf, Fred; Brose, Nils; Rhee, Jeong-Seop; Zhang, Weiqi; Ehrenreich, Hannelore

    2008-01-01

    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. PMID:18782446

  7. Erythropoietin and Cancer: The Unintended Consequences of Anemia Correction

    PubMed Central

    Debeljak, Nataša; Solár, Peter; Sytkowski, Arthur J.

    2014-01-01

    Until 1990, erythropoietin (EPO) was considered to have a single biological purpose and action, the stimulation of red blood cell growth and differentiation. Slowly, scientific and medical opinion evolved, beginning with the discovery of an effect on endothelial cell growth in vitro and the identification of EPO receptors (EPORs) on neuronal cells. We now know that EPO is a pleiotropic growth factor that exhibits an anti-apoptotic action on numerous cells and tissues, including malignant ones. In this article, we present a short discussion of EPO, receptors involved in EPO signal transduction, and their action on non-hematopoietic cells. This is followed by a more detailed presentation of both pre-clinical and clinical data that demonstrate EPO’s action on cancer cells, as well as tumor angiogenesis and lymphangiogenesis. Clinical trials with reported adverse effects of chronic erythropoiesis-stimulating agents (ESAs) treatment as well as clinical studies exploring the prognostic significance of EPO and EPOR expression in cancer patients are reviewed. Finally, we address the use of EPO and other ESAs in cancer patients. PMID:25426117

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

    NASA Astrophysics Data System (ADS)

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

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

  9. Use of erythropoietin and parenteral iron dextran in a severely anemic Jehovah's Witness with colon cancer.

    PubMed

    Madura, J A

    1993-10-01

    A Jehovah's Witness presented with colon cancer and profound anemia. On admission, her hemoglobin level was 30 g/L (3.0 g/dL). She refused all transfusions and failed to respond to oral iron therapy. She was ultimately prepared for surgery using recombinant human erythropoietin, iron dextran, and total parenteral nutrition. It took nearly 1 month to increase her hemoglobin level to an acceptable preoperative level of 110 g/L (11.0 g/dL). During the postoperative period, erythropoietin and parenteral iron therapy were briefly continued and a follow-up hemoglobin level of greater than 120 g/L (12.0 g/dL) was observed. Recombinant human erythropoietin, along with parenteral iron and adequate nutrition, may be useful in patients who refuse transfusion or cannot be transfused because of difficult cross-reacting antibodies.

  10. The anemia of primary autonomic failure and its reversal with recombinant erythropoietin

    NASA Technical Reports Server (NTRS)

    Biaggioni, I.; Robertson, D.; Krantz, S.; Jones, M.; Haile, V.

    1994-01-01

    OBJECTIVE: To determine if chronic sympathetic deprivation is associated with anemia and a low erythropoietin response. DESIGN: Survey of the prevalence and characteristics of anemia in patients with severe primary autonomic failure. SETTING: A referral service for autonomic failure in a tertiary teaching hospital. PATIENTS: 84 patients with primary autonomic failure who had symptomatic orthostatic hypotension. INTERVENTION: Open-label trial with human recombinant erythropoietin. RESULTS: Anemia was present in 32 of 84 patients (38%; 95% Cl, 27% to 50%). Plasma norepinephrine levels, measured in patients standing upright, were lower in the patient group with lower hemoglobin levels. Mean values in 22 patients with a hemoglobin level of less than 120 g/L were as follows: hemoglobin, 108 g/L (range, 87 to 118 g/L); hematocrit, 0.33; corrected reticulocyte counts, 0.008; mean corpuscular volume, 89 fL (89 microns 3); serum iron, 16.5 mumol/L (92 micrograms/dL); total iron binding capacity, 43.3 mumol/L (242 micrograms/dL); ferritin, 184 micrograms/L; serum vitamin B12, 410 pmol/L (556 pg/mL); and serum folate, 22.7 nmol/L (10 ng/mL). No relation was found between serum erythropoietin and blood hemoglobin levels. In seven of nine patients with autonomic failure who had hemoglobin levels less than 120 g/L, serum erythropoietin levels decreased below the 95% confidence interval corresponding to patients with iron deficiency anemia. Therapy with recombinant erythropoietin improved mean hemoglobin levels (from 108 to 133 g/L) in all patients treated (n = 5) at relatively low doses (25 to 50 units/kg body weight, subcutaneously, three times a week). CONCLUSIONS: Our data support the hypothesis that the sympathetic nervous system stimulates erythropoiesis in humans because anemia is a frequent occurrence in patients with severe autonomic failure and is associated with a blunted erythropoietin response.

  11. Incidence of erythropoietin antibody-mediated pure red cell aplasia: the Prospective Immunogenicity Surveillance Registry (PRIMS)

    PubMed Central

    Macdougall, Iain C.; Casadevall, Nicole; Locatelli, Francesco; Combe, Christian; London, Gerard M.; Di Paolo, Salvatore; Kribben, Andreas; Fliser, Danilo; Messner, Hans; McNeil, John; Stevens, Paul; Santoro, Antonio; De Francisco, Angel L.M.; Percheson, Paul; Potamianou, Anna; Foucher, Arnaud; Fife, Daniel; Mérit, Véronique; Vercammen, Els

    2015-01-01

    Background Subcutaneous administration of Eprex® (epoetin alfa) in patients with chronic kidney disease (CKD) was contraindicated in the European Union between 2002 and 2006 after increased reports of anti-erythropoietin antibody-mediated pure red cell aplasia (PRCA). The Prospective Immunogenicity Surveillance Registry (PRIMS) was conducted to estimate the incidence of antibody-mediated PRCA with subcutaneous administration of a new coated-stopper syringe presentation of Eprex® and to compare this with the PRCA incidence with subcutaneous NeoRecormon® (epoetin beta) and Aranesp® (darbepoetin alfa). Methods PRIMS was a multicentre, multinational, non-interventional, parallel-group, immunogenicity surveillance registry. Adults with CKD receiving or about to initiate subcutaneous Eprex®, NeoRecormon® or Aranesp® for anaemia were enrolled and followed for up to 3 years. Unexplained loss or lack of effect (LOE), including suspected PRCA, was reported, with antibody testing for confirmation of PRCA. Results Of the 15 333 patients enrolled, 5948 received Eprex® (8377 patient-years) and 9356 received NeoRecormon®/Aranesp® (14 286 patient-years). No treatment data were available for 29 patients. Among 23 patients with LOE, five cases of PRCA were confirmed (Eprex®, n = 3; NeoRecormon®, n = 1; Aranesp®, n = 1). Based on exposed time, PRCA incidence was 35.8/100 000 patient-years (95% CI 7.4–104.7) for Eprex® versus 14.0/100 000 patient-years (95% CI 1.7–50.6) for NeoRecormon®/Aranesp®. The incidence of PRCA with Eprex® was not significantly different versus comparator ESAs (rate ratio: 2.56; 95% CI 0.43–15.31). An analysis based on observed time produced similar findings. Conclusion This large, prospective registry demonstrates that PRCA is rare with subcutaneous administration of either the new coated-stopper syringe presentation of Eprex®, or NeoRecormon® or Aranesp®. PMID:25239637

  12. Localized and sustained delivery of erythropoietin from PLGA microspheres promotes functional recovery and nerve regeneration in peripheral nerve injury.

    PubMed

    Zhang, Wei; Gao, Yuan; Zhou, Yan; Liu, Jianheng; Zhang, Licheng; Long, Anhua; Zhang, Lihai; Tang, Peifu

    2015-01-01

    Erythropoietin (EPO) has been demonstrated to exert neuroprotective effects on peripheral nerve injury recovery. Though daily intraperitoneal injection of EPO during a long period of time was effective, it was a tedious procedure. In addition, only limited amount of EPO could reach the injury sites by general administration, and free EPO is easily degraded in vivo. In this study, we encapsulated EPO in poly(lactide-co-glycolide) (PLGA) microspheres. Both in vitro and in vivo release assays showed that the EPO-PLGA microspheres allowed sustained release of EPO within a period of two weeks. After administration of such EPO-PLGA microspheres, the peripheral nerve injured rats had significantly better recovery compared with those which received daily intraperitoneal injection of EPO, empty PLGA microspheres, or saline treatments. This was supported by the functional, electrophysiological, and histological evaluations of the recovery done at week 8 postoperatively. We conclude that sustained delivery of EPO could be achieved by using EPO-PLGA microspheres, and such delivery method could further enhance the recovery function of EPO in nerve injury recovery.

  13. Effect of recombinant human erythropoietin on mitomycin C-induced oxidative stress and genotoxicity in rat kidney and heart tissues.

    PubMed

    Rjiba-Touati, K; Ayed-Boussema, I; Guedri, Y; Achour, A; Bacha, H; Abid-Essefi, S

    2016-01-01

    Mitomycin C (MMC) is an antineoplastic agent used for the treatment of several human malignancies. Nevertheless, the prolonged use of the drug may result in a serious heart and kidney injuries. Recombinant human erythropoietin (rhEPO) has recently been shown to exert an important cytoprotective effect in experimental brain injury and ischemic acute renal failure. The aim of the present work is to investigate the cardioprotective and renoprotective effects of rhEPO against MMC-induced oxidative damage and genotoxicity. Our results showed that MMC induced oxidative stress and DNA damage. rhEPO administration in any treatment conditions decreased oxidative damage induced by MMC. It reduced malondialdehyde and protein carbonyl levels. rhEPO ameliorated reduced glutathione plus oxidized glutathione modulation and the increased catalase activity after MMC treatment. Furthermore, rhEPO restored DNA damage caused by MMC. We concluded that rhEPO administration especially in pretreatment condition protected rats against MMC-induced heart and renal oxidative stress and genotoxicity.

  14. Erythropoietin-enhanced endothelial progenitor cell recruitment in peripheral blood and renal vessels during experimental acute kidney injury in rats.

    PubMed

    Cakiroglu, Figen; Enders-Comberg, Sora Maria; Pagel, Horst; Rohwedel, Jürgen; Lehnert, Hendrik; Kramer, Jan

    2016-03-01

    Beneficial effects of erythropoietin (EPO) have been reported in acute kidney injury (AKI) when administered prior to induction of AKI. We studied the effects of EPO administration on renal function shortly after ischemic AKI. For this purpose, rats were subjected to renal ischemia for 30 min and EPO was administered at a concentration of 500 U/kg either i.v. as a single shot directly after ischemia or with an additional i.p. dose until 3 days after surgery. The results were compared with AKI rats without EPO application and a sham-operated group. Renal function was assessed by measurement of serum biochemical markers, histological grading, and using an isolated perfused kidney (IPK) model. Furthermore, we performed flow cytometry to analyze the concentration of endothelial progenitor cells (EPCs) in the peripheral blood and renal vessels. Following EPO application, there was only a statistically non-significant tendency of serum creatinine and urea to improve, particularly after daily EPO application. Renal vascular resistance and the renal perfusion rate were not significantly altered. In the histological analysis, acute tubular necrosis was only marginally ameliorated following EPO administration. In summary, we could not demonstrate a significant improvement in renal function when EPO was applied after AKI. Interestingly, however, EPO treatment resulted in a highly significant increase in CD133- and CD34-positive EPC both in the peripheral blood and renal vessels.

  15. Epobis is a Nonerythropoietic and Neuroprotective Agonist of the Erythropoietin Receptor with Anti-Inflammatory and Memory Enhancing Effects

    PubMed Central

    Korshunova, Irina

    2016-01-01

    The cytokine erythropoietin (EPO) stimulates proliferation and differentiation of erythroid progenitor cells. Moreover, EPO has neuroprotective, anti-inflammatory, and antioxidative effects, but the use of EPO as a neuroprotective agent is hampered by its erythropoietic activity. We have recently designed the synthetic, dendrimeric peptide, Epobis, derived from the sequence of human EPO. This peptide binds the EPO receptor and promotes neuritogenesis and neuronal cell survival. Here we demonstrate that Epobis in vitro promotes neuritogenesis in primary motoneurons and has anti-inflammatory effects as demonstrated by its ability to decrease TNF release from activated AMJ2-C8 macrophages and rat primary microglia. When administered systemically Epobis is detectable in both plasma and cerebrospinal fluid, demonstrating that the peptide crosses the blood-brain barrier. Importantly, Epobis is not erythropoietic, but systemic administration of Epobis in rats delays the clinical signs of experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis, and the peptide has long-term, but not short-term, effects on working memory, detected as an improved social memory 3 days after administration. These data reveal Epobis to be a nonerythropoietic and neuroprotective EPO receptor agonist with anti-inflammatory and memory enhancing properties. PMID:27990061

  16. Erythropoietin messenger RNA levels in developing mice and transfer of /sup 125/I-erythropoietin by the placenta

    SciTech Connect

    Koury, M.J.; Bondurant, M.C.; Graber, S.E.; Sawyer, S.T.

    1988-07-01

    Erythropoietin (EP) mRNA was measured in normal and anemic mice during fetal and postnatal development. Normal fetal livers at 14 d of gestation contained a low level of EP mRNA. By day 19 of gestation, no EP mRNA was detected in normal or anemic fetal livers or normal fetal kidneys, but anemic fetal kidneys had low levels of EP mRNA. Newborn through adult stage mice responded to anemia by accumulating renal and hepatic EP mRNA. However, total liver EP mRNA was considerably less than that of the kidneys. Juvenile animals, 1-4 wk old, were hyperresponsive to anemia in that they produced more EP mRNA than adults. Moreover, nonanemic juveniles had readily measured renal EP mRNA, whereas the adult level was at the lower limit of detection. Because of the very low level of fetal EP mRNA, placental transfer of EP was evaluated. When administered to the pregnant mouse, /sup 125/I-EP was transferred in significant amounts to the fetuses. These results indicate that in mice the kidney is the main organ of EP production at all stages of postnatal development and that adult kidney may also play some role in providing EP for fetal erythropoiesis via placental transfer of maternal hormone.

  17. Comparison of Neurite Outgrowth Induced by Erythropoietin (EPO) and Carbamylated Erythropoietin (CEPO) in Hippocampal Neural Progenitor Cells.

    PubMed

    Oh, Dong Hoon; Lee, In Young; Choi, Miyeon; Kim, Seok Hyeon; Son, Hyeon

    2012-08-01

    A previous animal study has shown the effects of erythropoietin (EPO) and its non-erythropoietic carbamylated derivative (CEPO) on neurogenesis in the dentate gyrus. In the present study, we sought to investigate the effect of EPO on adult hippocampal neurogenesis, and to compare the ability of EPO and CEPO promoting dendrite elongation in cultured hippocampal neural progenitor cells. Two-month-old male BALB/c mice were given daily injections of EPO (5 U/g) for seven days and were sacrificed 12 hours after the final injection. Proliferation assays demonstrated that EPO treatment increased the density of bromodeoxyuridine (BrdU)-labeled cells in the subgranular zone (SGZ) compared to that in vehicle-treated controls. Functional differentiation studies using dissociated hippocampal cultures revealed that EPO treatment also increased the number of double-labeled BrdU/microtubule-associated protein 2 (MAP2) neurons compared to those in vehicle-treated controls. Both EPO and CEPO treatment significantly increased the length of neurites and spine density in MAP2(+) cells. In summary, these results provide evidences that EPO and CEPO promote adult hippocampal neurogenesis and neuronal differentiation. These suggest that EPO and CEPO could be a good candidate for treating neuropsychiatric disorders such as depression and anxiety associated with neuronal atrophy and reduced hippocampal neurogenesis.

  18. Darbepoietin-alfa has comparable erythropoietic stimulatory effects to recombinant erythropoietin whilst preserving the bone marrow microenvironment.

    PubMed

    Dewamitta, Sita R; Russell, Megan R; Nandurkar, Harshal; Walkley, Carl R

    2013-05-01

    Erythropoiesis stimulating agents are widely used for the treatment of anemia. Recently, we reported erythroid expansion with impaired B lymphopoiesis and loss of trabecular bone in C57BL/6 mice following ten days of treatment with low-dose short acting recombinant human erythropoietin. We have assessed erythropoietin against longer-acting darbepoietin-alfa at a comparable erythroid stimulatory dosage regime. Darbepoietin-alfa and erythropoietin induced similar in vivo erythropoietic expansion. Both agents induced an expansion of the colony-forming unit-erythroid populations. However, unlike erythropoietin, darbepoietin-alfa did not impair bone marrow B lymphopoiesis. Strikingly the bone loss observed with erythropoietin was not apparent following darbepoietin-alfa treatment. This analysis demonstrates that whilst darbepoietin-alfa has similar in vivo erythropoietic potency to erythropoietin, it preserves the bone marrow microenvironment. Thus erythropoietin and darbepoietin-alfa manifest different action showing that erythropoiesis stimulating agents have differential non-erythroid effects dependent on their duration of action.

  19. Protection against cisplatin-induced nephrotoxicity by recombinant human erythropoietin.

    PubMed

    Yalcin, Suayib; Müftüoğlu, Sevda; Cetin, Eren; Sarer, Banu; Yildirim, Berna Akkuş; Zeybek, Dilara; Orhan, Bülent

    2003-01-01

    Cisplatin (CDDP) is a potent nephrotoxin, and nephrotoxicity is its most important dose-limiting toxicity. In this study, we aimed to investigate the role of recombinant human erythropoietin (rhEPO) in the protection of cisplatin-induced nephrotoxicity and compare its efficacy with the cell-protective agent amifostine. All experiments were conducted on female Wistar albino rats. Animals were randomly assigned to four groups, each including six rats. Group A received only CDDP, group B received CDDP plus rhEPO, group C received CDDP plus amifostine, and group D received only rhEPO. At the end of 7 wk, hemoglobin (Hgb), hematocrite (Htc), blood urea nitrogen (BUN), and creatinine (Cr) levels were determined and kidneys of the rats were removed. The weights of the kidneys were measured and sent for histopathological examination. Proximal tubules from four areas of the kidney (outer cortex, inner cortex, the medullary ray, and outer stripe of outer medulla [OSOM]) were evaluated. There were statistically significant differences among the groups in terms of tubular scores, including overall renal tubular score, cortex, inner cortex, OSOM, and medullary ray tubular scores, and Htc levels. Group A rats had the worse tubular scores in all categories when compared to group D rats. When the results of groups B and C were compared, there were no differences in terms of BUN, Cr levels, and tubular scores, but the Htc level was significantly higher in group B. Group B rats had better overall and OSOM tubular scores when compared to group A. Group C also had better overall and OSOM tubular scores compared to group A. The present study showed for the first time that rhEPO plays an important role in the prevention of cisplatin-induced nephrotoxicity and it is as effective as amifostine.

  20. Effects of systemic erythropoietin on ischemic wound healing in rats.

    PubMed

    Arslantaş, Mustafa Kemal; Arslantaş, Reyhan; Tozan, Emine Nur

    2015-03-01

    Results of in vivo studies have shown erythropoietin (EPO) is associated with anti-inflammatory, anti-apoptotic, and cell protective effects on wound healing. These effects are dose-dependent. The aim of this study was to evaluate whether the duration of EPO treatment affects the healing process in the ischemic wound. Forty-two (42) Sprague-Dawley rats were anesthetized, wounded with H-shaped flaps, and randomized to 2 groups; Group 1 received 400 u/kg/day EPO and Group 2 received a saline solution, both via intraperitoneal injection following the wounding. All substances were administered once daily at the same time for up to 10 days after surgery. At days 3, 5, and 10, 7 rats from each group were sacrificed. Skin samples were stained with hematoxylin/eosin, viewed under an optical microscope at 10X and 40X magnification, and analyzed by blinded investigators for re-epithelialization, neovascularization amount and maturation of granulation tissue, inflammatory cells, and ulcer healing using an evaluation scale where 0 = none; 1 = partial; 2 = complete, but immature/thin: and 4 = complete and mature. Blood hemoglobin and hematocrit levels also were measured. Data were analyzed using ANOVA one-way test (P <0.05). Hemoglobin and hematocrit levels rose while subsequent doses of EPO were administered over time, accompanied by a transient surge in healing on day 5, when differences in healing scores were significant. Flap necrosis, ulceration, and abscess were noted on post-wounding day 10 near the pedicle. The study showed EPO therapy can improve wound healing early in the post-wounding period but can reduce wound healing after post-injury treatment day 5. Further research is necessary, particularly to establish how EPO influences the microcirculation and rheology.

  1. Predialysis versus postdialysis hematocrit evaluation during erythropoietin therapy.

    PubMed

    Movilli, Ezio; Pertica, Nicoletta; Camerini, Corrado; Cancarini, Giovanni C; Brunori, Giuliano; Scolari, Francesco; Maiorca, Rosario

    2002-04-01

    American guidelines for the management of renal anemia by recombinant human erythropoietin (rHuEPO) recommend collecting a predialysis blood sample to evaluate hemoglobin (Hb) and hematocrit (Hct) levels in hemodialysis patients. Although a predialysis blood sample is appropriate for evaluating when to start rHuEPO treatment, the same sample would not be appropriate for evaluating the target Hb/Hct to be maintained, particularly when normal or near-normal values are pursued. We measured the degree of intradialytic and extradialytic variation of Hb, Hct, and body weight in 68 stable hemodialysis patients on maintenance subcutaneous rHuEPO treatment. Hb and Hct concentrations were determined before and after dialysis. In 16 patients, Hb and Hct concentrations also were assessed 24 hours after the end of dialysis. Predialysis versus postdialysis Hb and Hct concentrations for all patients were 10.5 +/- 1.3 g/dL versus 11.5 +/- 1.3 g/dL (P < 0.0001) and 32 +/- 4% versus 35 +/- 4% (P < 0.0001). The intradialytic percent variation (%Delta) of Hct and body weight were 10 +/- 6% and -6.3 +/- 3.5%. There was a close inverse correlation between %Delta of Hct and Hb and %Delta of body weight (P < 0.0001). In patients with body weight losses 2.5 kg or more per session, the mean %Delta of Hct was 12 +/- 7%. In the 16 patients studied 24 hours after the end of the dialysis session, Hct and Hb values remained significantly higher compared with the predialysis levels (P < 0.001), suggesting a slow reequilibration of the intravascular volume in the first 24 hours after hemodialysis. For these reasons, predialysis samples for monitoring the target Hb and Hct levels in patients treated by rHuEPO should be considered with caution.

  2. Plant recombinant erythropoietin attenuates inflammatory kidney cell injury.

    PubMed

    Conley, Andrew J; Mohib, Kanishka; Jevnikar, Anthony M; Brandle, Jim E

    2009-02-01

    Human erythropoietin (EPO) is a pleiotropic cytokine with remarkable tissue-protective activities in addition to its well-established role in red blood cell production. Unfortunately, conventional mammalian cell cultures are unlikely to meet the anticipated market demands for recombinant EPO because of limited capacity and high production costs. Plant expression systems may address these limitations to enable practical, cost-effective delivery of EPO in tissue injury prevention therapeutics. In this study, we produced human EPO in tobacco and demonstrated that plant-derived EPO had tissue-protective activity. Our results indicated that targeting to the endoplasmic reticulum (ER) provided the highest accumulation levels of EPO, with a yield approaching 0.05% of total soluble protein in tobacco leaves. The codon optimization of the human EPO gene for plant expression had no clear advantage; furthermore, the human EPO signal peptide performed better than a tobacco signal peptide. In addition, we found that glycosylation was essential for the stability of plant recombinant EPO, whereas the presence of an elastin-like polypeptide fusion had a limited positive impact on the level of EPO accumulation. Confocal microscopy showed that apoplast and ER-targeted EPO were correctly localized, and N-glycan analysis demonstrated that complex plant glycans existed on apoplast-targeted EPO, but not on ER-targeted EPO. Importantly, plant-derived EPO had enhanced receptor-binding affinity and was able to protect kidney epithelial cells from cytokine-induced death in vitro. These findings demonstrate that tobacco plants may be an attractive alternative for the production of large amounts of biologically active EPO.

  3. Targeted erythropoietin selectively stimulates red blood cell expansion in vivo

    PubMed Central

    Burrill, Devin R.; Vernet, Andyna; Collins, James J.; Silver, Pamela A.; Way, Jeffrey C.

    2016-01-01

    The design of cell-targeted protein therapeutics can be informed by natural protein–protein interactions that use cooperative physical contacts to achieve cell type specificity. Here we applied this approach in vivo to the anemia drug erythropoietin (EPO), to direct its activity to EPO receptors (EPO-Rs) on red blood cell (RBC) precursors and prevent interaction with EPO-Rs on nonerythroid cells, such as platelets. Our engineered EPO molecule was mutated to weaken its affinity for EPO-R, but its avidity for RBC precursors was rescued via tethering to an antibody fragment that specifically binds the human RBC marker glycophorin A (huGYPA). We systematically tested the impact of these engineering steps on in vivo markers of efficacy, side effects, and pharmacokinetics. huGYPA transgenic mice dosed with targeted EPO exhibited elevated RBC levels, with only minimal platelet effects. This in vivo selectivity depended on the weakening EPO mutation, fusion to the RBC-specific antibody, and expression of huGYPA. The terminal plasma half-life of targeted EPO was ∼28.3 h in transgenic mice vs. ∼15.5 h in nontransgenic mice, indicating that huGYPA on mature RBCs acted as a significant drug sink but did not inhibit efficacy. In a therapeutic context, our targeting approach may allow higher restorative doses of EPO without platelet-mediated side effects, and also may improve drug pharmacokinetics. These results demonstrate how rational drug design can improve in vivo specificity, with potential application to diverse protein therapeutics. PMID:27114509

  4. Recombinant human erythropoietin improves neurological outcomes in very preterm infants

    PubMed Central

    Song, Juan; Sun, Huiqing; Xu, Falin; Kang, Wenqing; Gao, Liang; Guo, Jiajia; Zhang, Yanhua; Xia, Lei; Wang, Xiaoyang

    2016-01-01

    Objective To evaluate the efficacy and safety of repeated low‐dose human recombinant erythropoietin (rhEPO) in the improvement of neurological outcomes in very preterm infants. Methods A total of 800 infants of ≤32‐week gestational age who had been in an intensive care unit within 72 hours after birth were included in the trial between January 2009 and June 2013. Preterm infants were randomly assigned to receive rhEPO (500IU/kg; n = 366) or placebo (n = 377) intravenously within 72 hours after birth and then once every other day for 2 weeks. The primary outcome was death or moderate to severe neurological disability assessed at 18 months of corrected age. Results Death and moderate/severe neurological disability occurred in 91 of 338 very preterm infants (26.9%) in the placebo group and in 43 of 330 very preterm infants (13.0%) in the rhEPO treatment group (relative risk [RR] = 0.40, 95% confidence interval [CI] = 0.27–0.59, p < 0.001) at 18 months of corrected age. The rate of moderate/severe neurological disability in the rhEPO group (22 of 309, 7.1%) was significantly lower compared to the placebo group (57 of 304, 18.8%; RR = 0.32, 95% CI = 0.19–0.55, p < 0.001), and no excess adverse events were observed. Interpretation Repeated low‐dose rhEPO treatment reduced the risk of long‐term neurological disability in very preterm infants with no obvious adverse effects. Ann Neurol 2016;80:24–34 PMID:27130143

  5. Charting a course for erythropoietin in traumatic brain injury

    PubMed Central

    Maiese, Kenneth

    2016-01-01

    Traumatic brain injury (TBI) is a severe public health problem that impacts more than four million individuals in the United States alone and is increasing in incidence on a global scale. Importantly, TBI can result in acute as well as chronic impairments for the nervous system leaving individuals with chronic disability and in instances of severe trauma, death becomes the ultimate outcome. In light of the significant negative health consequences of TBI, multiple therapeutic strategies are under investigation, but those focusing upon the cytokine and growth factor erythropoietin (EPO) have generated a great degree of enthusiasm. EPO can control cell death pathways tied to apoptosis and autophagy as well oversees processes that affect cellular longevity and aging. In vitro studies and experimental animal models of TBI have shown that EPO can restore axonal integrity, promote cellular proliferation, reduce brain edema, and preserve cellular energy homeostasis and mitochondrial function. Clinical studies for neurodegenerative disorders that involve loss of cognition or developmental brain injury support a positive role for EPO to prevent or reduce injury in the nervous system. However, recent clinical trials with EPO and TBI have not produced such clear conclusions. Further clinical studies are warranted to address the potential efficacy of EPO during TBI, the concerns with the onset, extent, and duration of EPO therapeutic strategies, and to focus upon the specific downstream pathways controlled by EPO such as protein kinase B (Akt), mechanistic target of rapamycin (mTOR), AMP activated protein kinase (AMPK), sirtuins, wingless pathways, and forkhead transcription factors for improved precision against the detrimental effects of TBI. PMID:27081573

  6. Erythropoietin: Powerful Protection of Ischemic and Post-Ischemic Brain

    PubMed Central

    Nguyen, Anh Q.; Cherry, Brandon H.; Scott, Gary F.; Ryou, Myoung-Gwi; Mallet, Robert T.

    2015-01-01

    Ischemic brain injury inflicted by stroke and cardiac arrest ranks among the leading causes of death and long-term disability in the United States. The brain consumes large amounts of metabolic substrates and oxygen to sustain its energy requirements. Consequently, the brain is exquisitely sensitive to interruptions in its blood supply, and suffers irreversible damage after 10–15 minutes of severe ischemia. Effective treatments to protect the brain from stroke and cardiac arrest have proven elusive, due to the complexities of the injury cascades ignited by ischemia and reperfusion. Although recombinant tissue plasminogen activator and therapeutic hypothermia have proven efficacious for stroke and cardiac arrest, respectively, these treatments are constrained by narrow therapeutic windows, potentially detrimental side effects and the limited availability of hypothermia equipment. Mounting evidence demonstrates the cytokine hormone erythropoietin (EPO) to be a powerful neuroprotective agent and a potential adjuvant to established therapies. Classically, EPO originating primarily in the kidneys promotes erythrocyte production by suppressing apoptosis of proerythroid progenitors in bone marrow. However, the brain is capable of producing EPO, and EPO’s membrane receptors and signaling components also are expressed in neurons and astrocytes. EPO activates signaling cascades that increase the brain’s resistance to ischemia-reperfusion stress by stabilizing mitochondrial membranes, limiting formation of reactive oxygen and nitrogen intermediates, and suppressing pro-inflammatory cytokine production and neutrophil infiltration. Collectively, these mechanisms preserve functional brain tissue and, thus, improve neurocognitive recovery from brain ischemia. This article reviews the mechanisms mediating EPO-induced brain protection, critiques the clinical utility of exogenous EPO to preserve brain threatened by ischemic stroke and cardiac arrest, and discusses the

  7. Erythropoietin Augments Survival of Glioma Cells After Radiation and Temozolomide

    SciTech Connect

    Hassouna, Imam; Sperling, Swetlana; Kim, Ella; Schulz-Schaeffer, Walter; Rave-Fraenk, Margret; Hasselblatt, Martin; Jelkmann, Wolfgang; Giese, Alf; Ehrenreich, Hannelore

    2008-11-01

    Purpose: Despite beneficial effects of irradiation/chemotherapy on survival of glioblastoma (GBM) patients, collateral damage to intact neural tissue leads to 'radiochemobrain' and reduced quality of life in survivors. For prophylactic neuroprotection, erythropoietin (EPO) is a promising candidate, provided that concerns regarding potential tumor promoting effects are alleviated. Methods and Materials: Human GBM-derived cell lines U87, G44, G112, and the gliosarcoma-derived line G28 were treated with EPO, with and without combinations of irradiation or temozolomide (TMZ). Responsiveness of glioma cells to EPO was measured by cell migration from spheroids, cell proliferation, and clonogenic survival. Implantation of U87 cells into brains of nude mice, followed 5 days later by EPO treatment (5,000 U/kg intraperitoneal every other day for 2 weeks) should reveal effects of EPO on tumor growth in vivo. Reverse transcriptase-polymerase chain reaction was performed for EPOR, HIF-1{alpha}, and epidermal growth factor receptor (EGFR)vIII in cell lines and 22 human GBM specimens. Results: EPO did not modulate basal glioma cell migration and stimulated proliferation in only one of four cell lines. Importantly, EPO did not enhance tumor growth in mouse brains. Preincubation of glioma cells with EPO for 3 h, followed by irradiation and TMZ for another 24 h, resulted in protection against chemoradiation-induced cytotoxicity in three cell lines. Conversely, EPO induced a dose-dependent decrease in survival of G28 gliosarcoma cells. In GBM specimens, expression of HIF-1{alpha} correlated positively with expression of EPOR and EGFRvIII. EPOR and EGFRvIII expression did not correlate. Conclusions: EPO is unlikely to appreciably influence basal glioma growth. However, concomitant use of EPO with irradiation/chemotherapy in GBM patients is not advisable.

  8. The Winding Pathway to Erythropoietin Along the Chemistry–Biology Frontier: A Success At Last

    PubMed Central

    Wilson, Rebecca M.; Dong, Suwei; Wang, Ping; Danishefsky, Samuel J.

    2016-01-01

    The total synthesis of a homogeneous erythropoietin, possessing the native amino acid sequence and chitobiose glycans at each of the three wild-type sites of N-glycosylation, has been accomplished in our laboratory. We provide herein an account of our decade-long research effort en route to this formidable target compound. PMID:23775885

  9. Postoperative high-dose intravenous iron sucrose with low dose erythropoietin therapy after total hip replacement.

    PubMed

    Yoon, Jiyeol; Kim, Sungmin; Lee, Soo Chan; Lim, Hongsub

    2010-12-01

    Erythropoietin combined with parenteral iron sucrose therapy is an alternative to blood transfusion in anemic patients. It was shown to be effective in surgical patients in several previous studies when used in conjunction with other methods. However, there are no guidelines about safety limits in dosage amounts or intervals. In this study, we report a case of significant postoperative hemorrhage managed with high dose parenteral iron sucrose, low dose erythropoietin, vitamin B(12), vitamin C, and folic acid. An 80-year-old female patient presented for severe anemia after a total hip arthroplasty and refused an allogenic blood transfusion as treatment. The preoperative hemoglobin of 12.2 g/dL decreased to 5.3 g/dL postoperatively. She received the aforementioned combination of iron sucrose, erythropoietin, and vitamins. A total of 1,500 mg of intravenous iron sucrose was given postoperatively for 6 consecutive days. Erythropoietin was also administered at 2,000 IU every other day for a total of 12,000 IU. The patient was discharged in good condition on the twelfth postoperative day with a hemoglobin of 8.5 g/dL. Her hemoglobin was at 11.2 g/dL on the twentieth postoperative day.

  10. Erythropoietin stimulation of human adipose tissue for therapeutic refilling releases protective cytokines

    PubMed Central

    Sabbatini, Maurizio; Bosetti, Michela; Borrone, Alessia; Moalem, Liah; Taveggia, Antonio; Verna, Giovanni; Cannas, Mario

    2016-01-01

    Apoptosis and inflammatory processes may be at the basis of reducing graft survival. Erythropoietin is a tissue-protective hormone with pleiotropic potential, and it interferes with the activities of pro-inflammatory cytokines and stimulates healing following injury, preventing destruction of tissue surrounding the injury site. It may represent a useful tool to increase the autograft integration. Through the use of multipanel kit cytokine analysis we have detected the cytokines secreted by human tissue adipose mass seeded in culture following withdrawal by Coleman’s modified technique in three groups: control, after lipopolysaccharides stimulation and after erythropoietin stimulation. In the control group, we have observed expression of factors that may have a role in protecting the tissue homeostatic mechanism. But the same factors were secreted following stimulation with lipopolysaccharides combined with others factors that delineated the inflammatory state. Instead through erythropoietin stimulation, the factors known to exert tissue-protective action were secreted. Therefore, the use of a trophic factors such as erythropoietin may help to inhibit the potential inflammatory process development and stimulate the activation of reparative/regenerative process in the tissue graft. PMID:27738510

  11. Computational and functional analysis of biopharmaceutical drugs in zebrafish: Erythropoietin as a test model.

    PubMed

    Guarienti, Michela; Giacopuzzi, Edoardo; Gianoncelli, Alessandra; Sigala, Sandra; Spano, Pierfranco; Pecorelli, Sergio; Pani, Luca; Memo, Maurizio

    2015-12-01

    The zebrafish (Danio rerio) is a very popular vertebrate model system, especially embryos represent a valuable tool for in vivo pharmacological assays. This is mainly due to the zebrafish advantages when compared to other animal models. Erythropoietin is a glycoprotein hormone that acts principally on erythroid progenitors, stimulating their survival, proliferation and differentiation. Recombinant human erythropoietin (rhEPO) has been widely used in medicine to treat anemia and it is one of the best-selling biotherapeutics worldwide. The recombinant molecule, industrially produced in CHO cells, has the same amino acid sequence of endogenous human erythropoietin, but differs in the glycosylation pattern. This may influence efficacy and safety, particularly immunogenicity, of the final product. We employed the zebrafish embryo as a vertebrate animal model to perform in vivo pharmacological assays. We conducted a functional analysis of rhEPO alpha Eprex(®) and two biosimilars, the erythropoietin alpha Binocrit(®) and zeta Retacrit(®). By in silico analysis and 3D modeling we proved the interaction between recombinant human erythropoietin and zebrafish endogenous erythropoietin receptor. Then we treated zebrafish embryos with the 3 rhEPOs and we investigated their effect on erythrocytes production with different assays. By real time-PCR we observed the relative upregulation of gata1 (2.4 ± 0.3 fold), embryonic α-Hb (1.9 ± 0.2 fold) and β-Hb (1.6 ± 0.1 fold) transcripts. A significant increase in Stat5 phosphorylation was also assessed in embryos treated with rhEPOs when compared with the negative controls. Live imaging in tg (kdrl:EGFP; gata1:ds-red) embryos, o-dianisidine positive area quantification and cyanomethemoglobin content quantification revealed a 1.8 ± 0.3 fold increase of erythrocytes amount in embryos treated with rhEPOs when compared with the negative controls. Finally, we verified that recombinant human erythropoietins did not cause any

  12. Characterization of the erythropoietin/erythropoietin receptor axis in a rat model of liver damage and cholangiocarcinoma development.

    PubMed

    Moriconi, Federico; Ramadori, Pierluigi; Schultze, Frank C; Blaschke, Martina; Amanzada, Ahmad; Khan, Sajjad; Ramadori, Giuliano

    2013-03-01

    It has been recently shown that the biological effects of erythropoietin (EPO) are not limited to the hematopoietic compartment but, as pleiotropic glycoprotein, this hormone can exert pro-angiogenic and tissue-protective functions also in a wide range of non-hematopoietic organs. The role of EPO and the effective functionality of its receptor in solid tumors are still a controversial point of debate. In the present work we analyzed the gene expression of EPO and its cognate receptor (EpoR) in a rat model of thioacetamide-induced damage and tumor. An analysis of the EPO/EpoR axis was also performed on human cholangiocarcinoma (CC) cell lines. A progressive increase of EPO and EpoR mRNA can already be observed during the fibrotic-cirrhotic development with a peak of expression rising at tumor formation (24.7 ± 9.9-fold increase and 15.5 ± 1.1-fold increase, respectively, for the two genes). Co-localization studies by immunofluorescence revealed hepatocytes in the regenerative cirrhotic nodules (Hep Par-1(+)) and in the dysplastic bile duct cells (CK19(+)) as the major EPO producers in this specific condition. The same cell populations, together with endothelial cells, exhibited an increased expression of EpoR, although all the non-parenchymal cell populations in the liver exhibited modest basal mRNA levels. Challenging human CC cells, Mz-Cha-2, with a combination of EPO and SCF resulted in a synergistic effect on the gene expression of EPO, CyclinD1 and PCNA. This study suggests that the autocrine and paracrine release of endogenous EPO in the microenvironment may contribute to the development and maintenance of the CC possibly in cooperation with other signaling pathways.

  13. Inhibitory effect on cerebral inflammatory agents that accompany traumatic brain injury in a rat model: a potential neuroprotective mechanism of recombinant human erythropoietin (rhEPO).

    PubMed

    Chen, Gang; Shi, Ji Xin; Hang, Chun Hua; Xie, Weiying; Liu, Jian; Liu, Xiaoming

    2007-10-02

    Erythropoietin (EPO) has recently been shown to have a neuroprotective effect in animal models of traumatic brain injury (TBI). However, the precise mechanisms remain unclear. Cerebral inflammation plays an important role in the pathogenesis of secondary brain injury after TBI. We, therefore, tried to analyze how recombinant human erythropoietin (rhEPO) might effect the inflammation-related factors common to TBI: nuclear factor kappa B (NF-kappaB), interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and intercellular adhesion molecule-1 (ICAM-1) in a rat TBI model. Male rats were given 0 or 5000 units/kg injections of rhEPO 1h post-injury and on days 1, 2 and 3 after surgery. Brain samples were extracted at 3 days after trauma. We measured NF-kappaB by electrophoretic mobility shift assay (EMSA); IL-1beta, TNF-alpha and IL-6 by enzyme-linked immunosorbent assay (ELISA); ICAM-1 by immunohistochemistry; brain edema by wet/dry method; blood-brain barrier (BBB) permeability by Evans blue extravasation and cortical apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method. We found that NF-kappaB, pro-inflammatory cytokines and ICAM-1 were increased in all injured animals. In animals given rhEPO post-TBI, NF-kappaB, IL-1beta, TNF-alpha and ICAM-1 were decreased in comparison to vehicle-treated animals. Measures of IL-6 showed no change after rhEPO treatment. Administration of rhEPO reduced brain edema, BBB permeability and apoptotic cells in the injured brain. In conclusion, post-TBI rhEPO administration may attenuate inflammatory response in the injured rat brain, and this may be one mechanism by which rhEPO improves outcome following TBI.

  14. Erythropoietin against cisplatin-induced peripheral neurotoxicity in rats.

    PubMed

    Orhan, Bulent; Yalcin, Suayib; Nurlu, Gulay; Zeybek, Dilara; Muftuoglu, Sevda

    2004-01-01

    Cisplatin (CDDP) is a potent anticancer drug, and neurotoxicity is one of its most important dose-limiting toxicities. In this study we investigated the role of recombinant human erythropoietin (rhuEPO) for protection against CDDP-induced neurotoxicity. All experiments were conducted on female Wistar-albino rats. Animals were randomly assigned to three groups. Group A received only CDDP, group B received CDDP plus rhuEPO, and group C received only rhuEPO. Electroneurography (ENG) was done in the beginning and at the end of 7 wk, then the rats were sacrificed and the sciatic nerve was removed for histopathological examination. The mean initial latency was 2.7438 ms in group A, 2.4875 ms in group B, and 2.62 ms in group C. After 7 wk of treatment, the latency was 2.4938, 2.6313, and 2.3900 ms, respectively. The difference in latencies was not statistically significant. The amplitude of compound muscle action potential (CMAP) was 12.8125 mV, 14.3875 mV, and 14.5600 mV before the treatment and 8.4875, 12.8250, and, 13.0800 mV after treatment, respectively. Amplitude of CMAP was significantly greater in rhuEPO-treated groups (groups B and C) compared to cisplatin only Group A. The mean area of CMAP was 12.2625, 12.3500, and, 12.2800 mV s before the treatment and 5.7125, 10.6463, and 9.1600 mV s after the treatment, respectively. The area of CMAP was significantly larger in rhuEPO-treated groups. In histopathological studies thick, thin, and total number of nerve fibers were 4053, 5050, and 9103, in group A, 5100, 8231, and 13331, in group B, and 5264, 6010, and 11274, in group C respectively. In the microscopic examination active myelinization process was observed in rhuEPO-treated groups. We concluded that at the given dose and schedule CDDP-induced motor neuropathy and rhuEPO prevented this neuropathy by sparing the number of normal nerve fibers and by protecting the amplitude and area of CMAP. We concluded that rhuEPO may also play a role in active myelinization and

  15. Erythropoietin promotes axonal regeneration after optic nerve crush in vivo by inhibition of RhoA/ROCK signaling pathway.

    PubMed

    Tan, Haibo; Zhong, Yisheng; Shen, Xi; Cheng, Yu; Jiao, Qin; Deng, Lianfu

    2012-11-01

    We investigated whether the RhoA/ROCK pathway was involved in the effect of erythropoietin (EPO) to promote retinal ganglion cells (RGCs) axonal regeneration in a rat optic nerve crush (ONC) model. We demonstrated that both EPO and ROCK inhibitor Y-27632 significantly enhanced RGCs survival and axon regeneration in vivo, and the effects of these agents were additive. Expression of active-RhoA was decreased after EPO or Y-27632 per pull down assay and affinity precipitation. Administration of EPO and Y-27632 cocktail resulted in even more RhoA inactivation, decreased expression of ROCK-1 and ROCK-2, and increased expression of growth associated protein-43 (GAP-43) protein per immunohistochemistry and western blot analysis. Down-regulation of active-RhoA, ROCK-1, and ROCK-2 expression by EPO coincided with the appearance of larger numbers of regenerating axons. In conclusion, the RhoA/ROCK signaling pathway was involved in the EPO effect to promote RGCs axon regeneration after ONC.

  16. Patients with anaemia can shift from kidney to liver production of erythropoietin as shown by glycoform analysis.

    PubMed

    Lönnberg, Maria; Garle, Mats; Lönnberg, Lina; Birgegård, Gunnar

    2013-01-01

    The primary production site of erythropoietin (EPO) is shifted from the liver to the kidney shortly after birth. Under conditions of lost or reduced kidney production, it is valuable to measure the production capacity of the liver. However, there is a lack of urine or serum based methods that can distinguish endogenous EPO produced in different cell types. Here is presented a method based on chromatographic interaction with the lectin wheat germ agglutinin (WGA) that can distinguish presumably liver-produced EPO, found in anaemic patients receiving epoetin and darbepoetin, from kidney-produced EPO found in healthy individuals. All the tested samples from haemodialysis patients with end-stage renal disease showed a presence of liver EPO. In some samples, the liver-produced EPO made up 90-100% of total EPO at a concentration of 8-10 ng/L in urine, which indicates that the liver has a quite high production capacity, although not adequate for the degree of anaemia. This glycoform analysis has made it possible to affirm that some anaemic patients can increase their liver-production of EPO. The use of such a method can give better insight into the regulation of non-renal endogenous EPO production, a potential source of EPO intended to replace administration of exogenous EPO.

  17. Anemia lessens and its prevention with recombinant human erythropoietin worsens glomerular injury and hypertension in rats with reduced renal mass.

    PubMed Central

    Garcia, D L; Anderson, S; Rennke, H G; Brenner, B M

    1988-01-01

    Chronic renal disease is frequently characterized by anemia, which may modify systemic and renal hemodynamics. In adult Munich-Wistar rats, the mild anemia (hematocrit, approximately equal to 42 vol/dl) that accompanies five-sixths nephrectomy was either made more severe (approximately equal to 30 vol/dl) by feeding a low iron diet or prevented (approximately equal to 50 vol/dl) by administration of recombinant human erythropoietin (r-HuEpo). In functional studies performed 4 weeks after renal ablation, untreated rats exhibited mild anemia with systemic hypertension and elevation of the single nephron glomerular filtration rate due to glomerular capillary hyperperfusion and hypertension. Preventing anemia with r-HuEpo worsened systemic and glomerular hypertension, effects largely obviated by induction of more marked anemia with the low iron diet. Untreated rats followed for 6 weeks postablation exhibited progressive proteinuria and sclerosis involving 12% of glomeruli, contrasted with 33% in rats given r-HuEpo. Even after 12 weeks, sclerosis involved only 6% of glomeruli in rats with more severe anemia but progressed to 30% in untreated rats. Thus, anemia limits systemic and glomerular hypertension and glomerular injury, whereas its prevention by r-HuEpo severely accelerates hemodynamically mediated glomerular injury in this model. These results suggest that anemia is a hemodynamically favorable adaptation to chronic renal disease and that its overly vigorous correction may have adverse renal hemodynamic and structural consequences. PMID:3413082

  18. In vivo erythropoietin requirements of regenerating erythroid progenitors (BFU-e, CFU-e) in bone marrow of mice.

    PubMed

    Udupa, K B; Reissmann, K R

    1979-06-01

    Erythroid progenitors (B-8, B-4, CFU-e) in the femoral marrow of polycythemic mice were measured by in vitro culture assays after a single administration of BCNU or Myleran. BCNU reduced pluripotent stem cells to 40% and erythroid progenitors to less than 5% of normal. B-8, the earliest erythroid progenitors, regenerated without erythropoietin (Epo) completely within 5 days. At 14 days after BCNU, intermediate progenitors (B-4) attained 60% of their normal numbers and CFU-e attained approximately 30%. Daily injections of Epo promptly restored normal B-4 numbers and near-normal CFU-e numbers in BCNU-treated mice. After Myleran, CFU-s remained below 2% of normal for 14 days, and no regeneration of the B-8 occurred with or without daily Epo injections. The findings suggest that regneration of B-8 was dependent on cell inflow from the pluripotent stem cell compartment but was independent of the presence of Epo. Intermediate progenitors (B-4) required Epo and the presence of B-8 for complete and permanent regeneration. CFU-e were the most Epo-dependent of the three progenitors. B-4, recruited by Epo, required after their formation a second exposure to the hormone in order to progress into the CFU-e stage.

  19. The effectiveness and safety of preoperative use of erythropoietin in patients scheduled for total hip or knee arthroplasty

    PubMed Central

    Zhao, Yan; Jiang, Chao; Peng, Huiming; Feng, Bin; Li, Yulong; Weng, Xisheng

    2016-01-01

    Abstract Introduction: Because allogeneic blood transfusion carries a risk of serious complications, erythropoietin (EPO) has been used in patients scheduled for total hip or knee arthroplasty in an effort to reduce the need for allogeneic blood transfusion; however, its efficacy, cost-effectiveness, and safety are still controversial. The purpose of this review was to determine the hematopoiesis-promoting effect and potential complications, as well as the cost-effectiveness, of preoperative use of EPO in patients scheduled for total hip or knee arthroplasty. Methods: : We searched MEDLINE, EMBASE, Cochrane, and ClinicalTrials.gov databases for relevant literature from 2000 to 2015. Risk of bias was assessed for all included studies and data were extracted and analyzed. Results: Preoperative use of EPO was associated with lower exposure to allogeneic blood transfusion (odds ratio = 0.41) and higher hemoglobin concentration after surgery (standardized mean difference = 0.86, P < 0.001). Complications were not generally reported, but there was no significant difference between the group with and without EPO based on given data. Cost-effectiveness was also summarized but was not conclusive. Conclusion: Preoperative administration of EPO reduces the requirement for allogeneic blood transfusion and increases hemoglobin level after surgery. The studies of cost-effectiveness were not conclusive. Further studies and guidelines specific to blood management in the perioperative stage of total knee and hip arthroplasty are expected. PMID:27399121

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

    PubMed

    Robach, Paul; Recalcati, Stefania; Girelli, Domenico; Gelfi, Cecilia; Aachmann-Andersen, Niels J; Thomsen, Jonas J; Norgaard, Anne M; Alberghini, Alessandra; Campostrini, Natascia; Castagna, Annalisa; Viganò, Agnese; Santambrogio, Paolo; Kempf, Tibor; Wollert, Kai C; Moutereau, Stéphane; Lundby, Carsten; Cairo, Gaetano

    2009-06-25

    The high iron demand associated with enhanced erythropoiesis during high-altitude hypoxia leads to skeletal muscle iron mobilization and decrease in myoglobin protein levels. To investigate the effect of enhanced erythropoiesis on systemic and muscle iron metabolism under nonhypoxic conditions, 8 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 in GDF-15. The increased iron use and reduced hepcidin levels suggested increased iron mobilization, but the treatment was associated with increased muscle iron and L ferritin levels. The muscle expression of transferrin receptor and ferroportin was up-regulated by rhEpo administration, whereas no appreciable change in myoglobin levels was observed, which suggests unaltered muscle oxygen homeostasis. In conclusion, under rhEpo stimulation, the changes in the expression of muscle iron proteins indicate the occurrence of skeletal muscle iron accumulation despite the remarkable hepcidin suppression that may be mediated by several factors, such as rhEpo or decreased transferrin saturation or both.

  1. Detection of recombinant human erythropoietin in urine for doping analysis: interpretation of isoelectric profiles by discriminant analysis.

    PubMed

    Lasne, Françoise; Thioulouse, Jean; Martin, Laurent; de Ceaurriz, Jacques

    2007-06-01

    The detection in urine of recombinant human erythropoietin (rHuEPO), a hormone misused by endurance athletes as a doping agent, is based on the differentiation of its isoelectric pattern from that of the corresponding natural hormone. Different empirical criteria have been proposed for discriminating the images of the patterns but none of them have been elaborated from a rational statistical approach. Discriminant analysis was applied to a dataset of profiles defined as positive (116 profiles from 26 subjects) (presence of rHuEPO and possibly residual natural endogenous hormone) and negative (131 profiles from 131 subjects) (presence of natural endogenous hormone only). The different bands were numbered according to a template of 16 possible positions and their relative intensities constituted the 16 variables of the statistical analysis. This method was then tested with data from an administration trial of low doses (6.7-10 IU/kg) following high-dose (265 IU/kg) injections (71 profiles from one subject). The analysis of the dataset clearly separated the negative and positive profiles. A cross-validation procedure confirmed that the analysis was extremely stable: with ten-fold cross-validation, no false positives were observed even with 100,000 simulations. Furthermore, the detection of rHuEPO in the profiles from the low-dose trial was greatly improved in comparison with a previously validated empirical criterion.

  2. Erythropoietin increases expression and function of transient receptor potential canonical 5 channels.

    PubMed

    Liu, Ying; Xu, Yunfei; Thilo, Florian; Friis, Ulla G; Jensen, Boye L; Scholze, Alexandra; Zheng, Junhua; Tepel, Martin

    2011-08-01

    Hypertension is a common complication in hemodialysis patients during erythropoietin (EPO) treatment. The underlying mechanisms of EPO-induced hypertension still remain to be determined. Increased transient receptor potential canonical (TRPC) channels have been associated with hypertension. Now, TRPC gene expression was investigated using quantitative real-time RT-PCR and immunoblotting in cultured human endothelial cells and in monocytes from hemodialysis patients. EPO dose-dependently increased TRPC5 mRNA in endothelial cells. EPO increased TRPC5 mRNA stability, that is, EPO prolonged the half-life period for TRPC5 mRNA from 16 hours (control) to 24 hours (P<0.05). The poly(A) tail length was measured by rapid amplification of cDNA ends-poly(A) test. Increased TRPC5 mRNA stability was attributed to longer 3' poly(A) tail lengths after EPO administration. EPO also significantly increased TRPC5 channel protein abundance by 70% (P<0.05). Whole-cell patch clamp showed that angiotensin II-induced, TRPC5-mediated currents were dramatically increased in endothelial cells treated with EPO. Fluorescent dye techniques confirmed that increased calcium influx after EPO treatment was abolished after TRPC5 knockdown (P<0.05). EPO also significantly increased intracellular reactive oxygen species production. Knockdown of TRPC5 alleviated EPO-induced reactive oxygen species generation in endothelial cells (P<0.05). In vivo, EPO-treated hemodialysis patients showed significantly increased amounts of TRPC5 mRNA in monocytes compared with EPO-free hemodialysis patients (6.0±2.4 [n=12] versus 1.0±0.5 [n=9]; P<0.01). Patients undergoing EPO treatment also showed significantly elevated systolic blood pressure (160±7 versus 139±6 mm Hg; P<0.05). Our findings suggest that upregulated functional TRPC5 gene may be one cause of EPO-induced hypertension in patients with chronic kidney disease.

  3. Effect of recombinant erythropoietin on ischemia-reperfusion-induced apoptosis in rat liver.

    PubMed

    Shawky, Heba M; Younan, Sandra M; Rashed, Leila A; Shoukry, Heba

    2012-03-01

    Ischemia-reperfusion (I/R) cannot be avoided in liver transplantation procedures, and apoptosis is a central mechanism of cell death after liver reperfusion. Protective effect of recombinant erythropoietin (rhEPO) on liver apoptosis has not been clearly investigated. This work investigated intraportal (IP) rhEPO-protective effect in a rat model of hepatic I/R-induced apoptosis and its appropriated time and dose of administration. Eight groups were included (n = 10/group): sham-operated, I/R (45 min ischemia and 2 h reperfusion), preconditioned rhEPO I/R (24 h or 30 min before ischemia), and postconditioned rhEPO I/R (before reperfusion) using two different rhEPO doses (1,000 and 5,000 IU/kg). When compared with the sham-operated group, the I/R group showed significant increase of serum levels of aspartate and alanine aminotransferases (AST, ALT), hepatic caspase-9 activity(894.99 ± 176.90 relative fluorescence units (RFU)/mg/min versus 458.48 ± 82.96 RFU/mg/min), and Fas ligand (FasL) expression, histopathological damages, and significant decrease in the antiapoptotic Bcl-xL/apoptotic Bax ratio(0.38 ± 0.21 versus 3.35 ± 0.77) rhEPO-improved ALT and AST but failed to reduce FasL expression in all groups compared with the I/R group. Thirty minutes and 24 h preconditioning with rhEPO (1,000 IU/kg) increased Bcl-xL/Bax ratio and reduced caspase-9 activity, and the same effect was observed when higher dose was given 24 h before ischemia. Preconditioning was more effective than postconditioning in improving caspase-9 activity, and no dose-dependent effect was observed. In conclusion, single IP rhEPO injection 30 min before ischemia has an advantage over rhEPO postconditioning in improving post-hepatic I/R-induced apoptosis with no additional time- and dose-dependent effects which may provide potentially useful guide in liver transplantation procedures.

  4. Mathematical modeling reveals differential effects of erythropoietin on proliferation and lineage commitment of human hematopoietic progenitors in early erythroid culture

    PubMed Central

    Ward, Daniel; Carter, Deborah; Homer, Martin; Marucci, Lucia; Gampel, Alexandra

    2016-01-01

    Erythropoietin is essential for the production of mature erythroid cells, promoting both proliferation and survival. Whether erythropoietin and other cytokines can influence lineage commitment of hematopoietic stem and progenitor cells is of significant interest. To study lineage restriction of the common myeloid progenitor to the megakaryocyte/erythroid progenitor of peripheral blood CD34+ cells, we have shown that the cell surface protein CD36 identifies the earliest lineage restricted megakaryocyte/erythroid progenitor. Using this marker and carboxyfluorescein succinimidyl ester to track cell divisions in vitro, we have developed a mathematical model that accurately predicts population dynamics of erythroid culture. Parameters derived from the modeling of cultures without added erythropoietin indicate that the rate of lineage restriction is not affected by erythropoietin. By contrast, megakaryocyte/erythroid progenitor proliferation is sensitive to erythropoietin from the time that CD36 first appears at the cell surface. These results shed new light on the role of erythropoietin in erythropoiesis and provide a powerful tool for further study of hematopoietic progenitor lineage restriction and erythropoiesis. PMID:26589912

  5. Administrative Synergy

    ERIC Educational Resources Information Center

    Hewitt, Kimberly Kappler; Weckstein, Daniel K.

    2012-01-01

    One of the biggest obstacles to overcome in creating and sustaining an administrative professional learning community (PLC) is time. Administrators are constantly deluged by the tyranny of the urgent. It is a Herculean task to carve out time for PLCs, but it is imperative to do so. In this article, the authors describe how an administrative PLC…

  6. Comparison among three anion exchange chromatographic supports to capture erythropoietin from cell culture supernatant.

    PubMed

    Hernández, Lourdes; Stewart, Diobel; Zumalacárregui, Lourdes; Amaro, Daniel

    2015-06-01

    Affinity and ion exchange conventional chromatography have been used to capture erythropoietin (EPO) from mammalian cell culture supernatant. Currently, chromatographic adsorbent perfusion is available, however a limited number of applications have been found in the literature. In this work, three anion exchange chromatographic supports (gel, membrane and monolithic) were evaluated in the capture step of the recombinant erythropoietin purification process. The influences of load and flow rate on each support performance were analyzed. Also the purity of the EPO molecules was determined. A productivity analysis, as a decision tool for larger scale implementation, was done. As a conclusion, the evaluated supports are technically suitable to capture EPO with adequate recovery and good purity. However, the monolithic column admits high operating velocity, showing the highest adsorption capacity and productivity.

  7. Serum erythropoietin titers during prolonged bedrest; relevance to the "anaemia" of space flight.

    PubMed

    Dunn, C D; Lange, R D; Kimzey, S L; Johnson, P C; Leach, C S

    1984-01-01

    The overall objective of these studies was to test the hypothesis that the suppression of erythropoiesis, which occurs during both spaceflight and bedrest, was mediated by reduction in circulating levels of erythropoietin. In each of two 7-day studies, groups of subjects were exposed to either horizontal or 6 degrees head-down tilt bedrest and no evidence was obtained to suggest that the erythropoietic effects were dependent on the angle of recumbency. An additional study involved six men who were exposed to horizontal bedrest for 28 days. Serum erythropoietin titers were not significantly depressed in any of the subjects but total red cell volume was decreased. Absolute increases in red cell numbers and reductions in plasma volume both elevate the haematocrit, but our data suggest that the mechanism of erythrosuppression in these two instances may be different.

  8. Secondary polycythaemia associated with high plasma erythropoietin concentrations in a dog with a necrotising pyelonephritis.

    PubMed

    Kessler, M

    2008-07-01

    An 11-year-old mixed breed dog was presented with anorexia, apathy and intermittent macrohaematuria, absolute polycythaemia (packed cell volume, 80 per cent; red blood cell, 12.2 x 10(6)/microl) and elevated erythropoietin concentrations. A renal mass was detected by ultrasonography and, following total nephrectomy, diagnosed as necrotising pyelonephritis. After surgery, the haematological parameters and erythropoietin values returned to normal, suggesting that the pyelonephritis was the cause of the polycythaemia. While secondary polycythaemia because of a non-neoplastic condition of the kidneys occasionally occurs in human beings, it has only extremely rarely been reported in dogs. This is the first case report of a unilateral pyelonephritis causing secondary polycythaemia in a dog.

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

    PubMed

    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.

  10. Changes in erythropoietin levels during space flight or space flight simulation

    NASA Technical Reports Server (NTRS)

    Dunn, C. D. R.; Hen, J. P.

    1980-01-01

    Two hundred and seventy samples from 24 subjects involved in 3 bedrest studies and from 3 subjects involved in Spacelab Mission Development Test 3 were assayed for erythropoietin (Ep), in an in vitro fetal mouse liver cell assay, and for ferritin using a commercially available immunoradiometric assay kit. No trends or significant changes in serum Ep were observed. Serum ferritin concentrations tended to increases slightly during the 'missions', reflecting a redirection of iron from the suppressed erythron into iron stores.

  11. Expression of GPI anchored human recombinant erythropoietin in CHO cells is devoid of glycosylation heterogeneity.

    PubMed

    Singh, Pankaj Kumar; Devasahayam, Mercy; Devi, Sobita

    2015-04-01

    Erythropoietin is a glycohormone involved in the regulation of the blood cell levels. It is a 166 amino acid protein having 3 N-glycosylation and one O-linked glycosylation sites, and is used to treat anaemia related illness. Though human recombinant erythropoietin (rEPO) is produced in CHO cells, the loss in quality control is 80% due to incomplete glycosylation of the rEPO with low levels of fully glycosylated active rEPO. Here, we describe the expression from CHO cells of fully glycosylated human rEPO when expressed as a GPI anchored molecule (rEPO-g). The results demonstrated the production of a homogenous completely glycosylated human rEPO-g as a 42 kD band without any low molecular weight glycoform variants as shown by affinity chromatography followed by SDS-PAGE and anti-human EPO specific western blot. The western blot using specific monoclonal antibody is the available biochemical technique to prove the presence of homogeneity in the expressed recombinant protein. The GPI anchor can be removed during the purification process to yield a therapeutically relevant recombinant erythropoietin molecule cells with a higher in vivo biological activity due to its high molecular weight of 40 kD. This is possibly the first report on the production of a homogenous and completely glycosylated human rEPO from CHO cells for efficient therapy.

  12. Isoforms of the Erythropoietin receptor in dopaminergic neurons of the Substantia Nigra.

    PubMed

    Marcuzzi, Federica; Zucchelli, Silvia; Bertuzzi, Maria; Santoro, Claudio; Tell, Gianluca; Carninci, Piero; Gustincich, Stefano

    2016-11-01

    Erythropoietin receptor (EpoR) regulates erythrocytes differentiation in blood. In the brain, EpoR has been shown to protect several neuronal cell types from cell death, including the A9 dopaminergic neurons (DA) of the Substantia Nigra (SN). These cells form the nigrostriatal pathway and are devoted to the control of postural reflexes and voluntary movements. Selective degeneration of A9 DA neurons leads to Parkinson's disease. By the use of nanoCAGE, a technology that allows the identification of Transcription Start Sites (TSSs) at a genome-wide level, we have described the promoter-level expression atlas of mouse A9 DA neurons purified with Laser Capture Microdissection (LCM). Here, we identify mRNA variants of the Erythropoietin Receptor (DA-EpoR) transcribed from alternative TSSs. Experimental validation and full-length cDNA cloning is integrated with gene expression analysis in the FANTOM5 database. In DA neurons, the EpoR gene encodes for a N-terminal truncated receptor. Based on STAT5 phosphorylation assays, we show that the new variant of N-terminally truncated EpoR acts as decoy when co-expressed with the full-length form. A similar isoform is also found in human. This work highlights new complexities in the regulation of Erythropoietin (EPO) signaling in the brain.

  13. Administrative Ecology

    ERIC Educational Resources Information Center

    McGarity, Augustus C., III; Maulding, Wanda

    2007-01-01

    This article discusses how all four facets of administrative ecology help dispel the claims about the "impossibility" of the superintendency. These are personal ecology, professional ecology, organizational ecology, and community ecology. Using today's superintendency as an administrative platform, current literature describes a preponderance of…

  14. Randomized Trial of Neuroprotective Effects of Erythropoietin in Patients Receiving Adjuvant Chemotherapy for Breast Cancer: Positron Emission Tomography and Neuropsychological Study

    DTIC Science & Technology

    2008-09-01

    Effects of Erythropoietin in Patients Receiving Adjuvant Chemotherapy for Breast Cancer : Positron Emission Tomography and Neuropsychological Study...Neuroprotective Effects of Erythropoietin in Patients 5a. CONTRACT NUMBER Receiving Adjuvant Chemotherapy for Breast Cancer : Positron Emission Tomography...11 Introduction In the United States approximately 60-80% of patients diagnosed with breast cancer will receive

  15. Partial white and grey matter protection with prolonged infusion of recombinant human erythropoietin after asphyxia in preterm fetal sheep.

    PubMed

    Wassink, Guido; Davidson, Joanne O; Dhillon, Simerdeep K; Fraser, Mhoyra; Galinsky, Robert; Bennet, Laura; Gunn, Alistair J

    2017-03-01

    Perinatal asphyxia in preterm infants remains a significant contributor to abnormal long-term neurodevelopmental outcomes. Recombinant human erythropoietin has potent non-haematopoietic neuroprotective properties, but there is limited evidence for protection in the preterm brain. Preterm (0.7 gestation) fetal sheep received sham asphyxia (sham occlusion) or asphyxia induced by umbilical cord occlusion for 25 min, followed by an intravenous infusion of vehicle (occlusion-vehicle) or recombinant human erythropoietin (occlusion-Epo, 5000 international units by slow push, then 832.5 IU/h), starting 30 min after asphyxia and continued until 72 h. Recombinant human erythropoietin reduced neuronal loss and numbers of caspase-3-positive cells in the striatal caudate nucleus, CA3 and dentate gyrus of the hippocampus, and thalamic medial nucleus ( P < 0.05 vs. occlusion-vehicle). In the white matter tracts, recombinant human erythropoietin increased total, but not immature/mature oligodendrocytes ( P < 0.05 vs. occlusion-vehicle), with increased cell proliferation and reduced induction of activated caspase-3, microglia and astrocytes ( P < 0.05). Finally, occlusion-Epo reduced seizure burden, with more rapid recovery of electroencephalogram power, spectral edge frequency, and carotid blood flow. In summary, prolonged infusion of recombinant human erythropoietin after severe asphyxia in preterm fetal sheep was partially neuroprotective and improved electrophysiological and cerebrovascular recovery, in association with reduced apoptosis and inflammation.

  16. Mimicking Hypoxia to Treat Anemia: HIF-Stabilizer BAY 85-3934 (Molidustat) Stimulates Erythropoietin Production without Hypertensive Effects

    PubMed Central

    Flamme, Ingo; Oehme, Felix; Ellinghaus, Peter; Jeske, Mario; Keldenich, Jörg; Thuss, Uwe

    2014-01-01

    Oxygen sensing by hypoxia-inducible factor prolyl hydroxylases (HIF-PHs) is the dominant regulatory mechanism of erythropoietin (EPO) expression. In chronic kidney disease (CKD), impaired EPO expression causes anemia, which can be treated by supplementation with recombinant human EPO (rhEPO). However, treatment can result in rhEPO levels greatly exceeding the normal physiological range for endogenous EPO, and there is evidence that this contributes to hypertension in patients with CKD. Mimicking hypoxia by inhibiting HIF-PHs, thereby stabilizing HIF, is a novel treatment concept for restoring endogenous EPO production. HIF stabilization by oral administration of the HIF-PH inhibitor BAY 85-3934 (molidustat) resulted in dose-dependent production of EPO in healthy Wistar rats and cynomolgus monkeys. In repeat oral dosing of BAY 85-3934, hemoglobin levels were increased compared with animals that received vehicle, while endogenous EPO remained within the normal physiological range. BAY 85-3934 therapy was also effective in the treatment of renal anemia in rats with impaired kidney function and, unlike treatment with rhEPO, resulted in normalization of hypertensive blood pressure in a rat model of CKD. Notably, unlike treatment with the antihypertensive enalapril, the blood pressure normalization was achieved without a compensatory activation of the renin–angiotensin system. Thus, BAY 85-3934 may provide an approach to the treatment of anemia in patients with CKD, without the increased risk of adverse cardiovascular effects seen for patients treated with rhEPO. Clinical studies are ongoing to investigate the effects of BAY 85-3934 therapy in patients with renal anemia. PMID:25392999

  17. Remote conditioning or erythropoietin before surgery primes kidneys to clear ischemia-reperfusion-damaged cells: a renoprotective mechanism?

    PubMed

    Gardner, David S; Welham, Simon J M; Dunford, Louise J; McCulloch, Thomas A; Hodi, Zsolt; Sleeman, Philippa; O'Sullivan, Saoirse; Devonald, Mark A J

    2014-04-15

    Acute kidney injury is common, serious with no specific treatment. Ischemia-reperfusion is a common cause of acute kidney injury (AKI). Clinical trials suggest that preoperative erythropoietin (EPO) or remote ischemic preconditioning may have a renoprotective effect. Using a porcine model of warm ischemia-reperfusion-induced AKI (40-min bilateral cross-clamping of renal arteries, 48-h reperfusion), we examined the renoprotective efficacy of EPO (1,000 iu/kg iv.) or remote ischemic preconditioning (3 cycles, 5-min inflation/deflation to 200 mmHg of a hindlimb sphygmomanometer cuff). Ischemia-reperfusion induced significant kidney injury at 24 and 48 h (χ(2), 1 degree of freedom, >10 for 6/7 histopathological features). At 2 h, a panel of biomarkers including plasma creatinine, neutrophil gelatinase-associated lipocalin, and IL-1β, and urinary albumin:creatinine could be used to predict histopathological injury. Ischemia-reperfusion increased cell proliferation and apoptosis in the renal cortex but, for pretreated groups, the apoptotic cells were predominantly intratubular rather than interstitial. At 48-h reperfusion, plasma IL-1β and the number of subcapsular cells in G2-M arrest were reduced after preoperative EPO, but not after remote ischemic preconditioning. These data suggest an intrarenal mechanism acting within cortical cells that may underpin a renoprotective function for preoperative EPO and, to a limited extent, remote ischemic preconditioning. Despite equivocal longer-term outcomes in clinical studies investigating EPO as a renoprotective agent in AKI, optimal clinical dosing and administration have not been established. Our data suggest further clinical studies on the potential renoprotective effect of EPO and remote ischemic preconditioning are justified.

  18. Brain penetrating IgG-erythropoietin fusion protein is neuroprotective following intravenous treatment in Parkinson's disease in the mouse.

    PubMed

    Zhou, Qing-Hui; Hui, Eric Ka-Wai; Lu, Jeff Zhiqiang; Boado, Ruben J; Pardridge, William M

    2011-03-25

    Parkinson's disease (PD) is caused by oxidative stress, and erythropoietin (EPO) reduces oxidative stress in the brain. However, EPO cannot be developed as a treatment for PD, because EPO does not cross the blood-brain barrier (BBB). A brain penetrating form of human EPO has been developed wherein EPO is fused to a chimeric monoclonal antibody (MAb) against the mouse transferrin receptor (TfR), which is designated as the cTfRMAb-EPO fusion protein. The TfRMAb acts as a molecular Trojan horse to transport the fused EPO into brain via transport on the BBB TfR. Experimental PD was induced in adult mice by the intra-striatal injection of 6-hydroxydopamine, and PD mice were treated with 1mg/kg of the cTfRMAb-EPO fusion protein intravenously (IV) every other day starting 1 h after toxin injection. Following 3weeks of treatment mice were euthanized for measurement of striatal tyrosine hydroxylase (TH) enzyme activity. Mice treated with the cTfRMAb-EPO fusion protein showed a 306% increase in striatal TH enzyme activity, which correlated with improvement in three assays of neurobehavior. The blood hematocrit increased 10% at 2weeks, with no further changes at 3weeks of treatment. A sandwich ELISA showed the immune reaction against the cTfRMAb-EPO fusion protein was variable and low titer. In conclusion, the present study demonstrates that a brain penetrating form of EPO is neuroprotective in PD following IV administration with minimal effects on erythropoiesis.

  19. Exercise aggravates cardiovascular risks and mortality in rats with disrupted nitric oxide pathway and treated with recombinant human erythropoietin.

    PubMed

    Meziri, Fayçal; Binda, Delphine; Touati, Sabeur; Pellegrin, Maxime; Berthelot, Alain; Touyz, Rhian M; Laurant, Pascal

    2011-08-01

    Chronic administration of recombinant human erythropoietin (rHuEPO) can generate serious cardiovascular side effects such as arterial hypertension (HTA) in clinical and sport fields. It is hypothesized that nitric oxide (NO) can protect from noxious cardiovascular effects induced by chronic administration of rHuEPO. On this base, we studied the cardiovascular effects of chronic administration of rHuEPO in exercise-trained rats treated with an inhibitor of NO synthesis (L-NAME). Rats were treated or not with rHuEPO and/or L-NAME during 6 weeks. During the same period, rats were subjected to treadmill exercise. The blood pressure was measured weekly. Endothelial function of isolated aorta and small mesenteric arteries were studied and the morphology of the latter was investigated. L-NAME induced hypertension (197 ± 6 mmHg, at the end of the protocol). Exercise prevented the rise in blood pressure induced by L-NAME (170 ± 5 mmHg). However, exercise-trained rats treated with both rHuEPO and L-NAME developed severe hypertension (228 ± 9 mmHg). Furthermore, in these exercise-trained rats treated with rHuEPO/L-NAME, the acetylcholine-induced relaxation was markedly impaired in isolated aorta (60% of maximal relaxation) and small mesenteric arteries (53%). L-NAME hypertension induced an internal remodeling of small mesenteric arteries that was not modified by exercise, rHuEPO or both. Vascular ET-1 production was not increased in rHuEPO/L-NAME/training hypertensive rats. Furthermore, we observed that rHuEPO/L-NAME/training hypertensive rats died during the exercise or the recovery period (mortality 51%). Our findings suggest that the use of rHuEPO in sport, in order to improve physical performance, represents a high and fatal risk factor, especially with pre-existing cardiovascular risk.

  20. Red blood cell cation transports in uraemic anaemia: evidence for an increased K/Cl co-transport activity. Effects of dialysis and erythropoietin treatment.

    PubMed

    De Franceschi, L; Olivieri, O; Girelli, D; Lupo, A; Bernich, P; Corrocher, R

    1995-10-01

    This study examines the role of uraemia and the effect of different dialysis treatments on red cell cation transport. We evaluated the main cation transport systems in erythrocytes of non-dialysed end-stage renal disease (ESRD) subjects, of patients undergoing haemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD), as well as the changes induced by human recombinant erythropoietin (r-HuEPO) administration. In uraemic undialysed and dialysed patients, we observed an increase in K/Cl co-transport activity and in shrinkage-induced amiloride-sensitive (HMA-sensitive) Na efflux (Na/H exchange) and a decrease in Na/K pump and Na/K/Cl co-transport activity, while Na/Li exchange was increased only in dialysed patients. In uraemic erythrocytes, we showed for the first time an increased K/Cl co-transport activity, which was cell age independent. Generally, the different method of dialysis (CAPD or HD) did not modify the cation transport abnormalities observed. During the treatment with r-HuEPO, all the systems, with the exception of the Na/K pump and Na/K/Cl co-transport, increased their activities following the increase of circulating young red cells. The changes produced under r-HuEPO administration were transient and cation transports returned to the baseline values within 100 days of treatment, indicating a primary and prominent pathogenetic role of uraemia in modulating the red cell membrane cation transport activities.

  1. Clinical efficacy and safety of recombinant canine erythropoietin in dogs with anemia of chronic renal failure and dogs with recombinant human erythropoietin-induced red cell aplasia.

    PubMed

    Randolph, John E; Scarlett, Janet; Stokol, Tracy; MacLeod, James N

    2004-01-01

    The efficacy and safety of recombinant canine erythropoietin (rcEPO) therapy was evaluated in 19 dogs with anemia of chronic renal failure (group 1) and 6 dogs with chronic renal failure and recombinant human erythropoietin (rhEPO)-induced red cell aplasia (group 2). Hematocrit (Hct) and absolute reticulocyte count (ARC) were monitored weekly for the first 8 weeks, CBC (including ARC) and serum iron profiles were evaluated monthly, and serum biochemical analyses were performed every 2 months for 6 (group 2) to 12 (group 1) months. For group 1 dogs, median Hct and ARC increased significantly during the 1st week of rcEPO treatment, and median Hct was sustained at >35% after week 5. In contrast, median Hct and ARC for group 2 did not change significantly with rcEPO treatment, even with doses greater than those used in group 1. Nevertheless, 2 (33%) of the 6 dogs in group 2 developed erythroid hyperplasia, reticulocytosis, and increases in Hct with rcEPO treatment. Although median systolic blood pressure did not change significantly in either group, 5 dogs developed systolic blood pressures > or = 180 mm Hg during the study. Appetite and energy level improved in most group 1 dogs with increases in Hct. Recombinant cEPO stimulated erythrocyte production in dogs with nonregenerative anemia secondary to chronic renal failure without causing the profound erythroid hypoplasia that can occur in rhEPO-treated dogs. Unfortunately, rcEPO was not as effective in restoring erythrocyte production in dogs that had previously developed rhEPO-induced red cell aplasia.

  2. Oxidative stress during erythropoietin hyporesponsiveness anemia at end stage renal disease: Molecular and biochemical studies

    PubMed Central

    Khalil, Samar K.M.; Amer, H.A.; El Behairy, Adel M.; Warda, Mohamad

    2016-01-01

    Inflammation and oxidative stress are two faces of one coin in end stage renal disease patients (ESRD) on maintenance hemodialysis. Their interconnection induces anemia complicated with erythropoietin hyporesponsiveness. The biochemical bases behind the resistance to erythropoietin therapy with frequent hemoglobinemia, oxidative stress and iron status have not been fully understood. Here two equal groups (40 patients each) of responders and non-responders to recombinant human erythropoietin therapy (higher than 300 IU/kg/wk of epoetin) were investigated. Hematological and biochemical analyses of collected blood and serum samples were performed along with serum electrophoretic protein footprinting. The leukocytic DNA fragmentation was used to evaluate the degree of oxidative insult. The good responders showed lower erythrocyte malondialdehyde (E-MDA) level and less DNA fragmentation of circulating leukocytes than poor responders with elevated hemoglobin, albumin, A/G ratio, total iron, and ferritin levels. Contrariwise, lower erythrocyte superoxide dismutase (E-SOD) and catalase activities in EPO poor responder group were noticed. Neither other serum constituents nor electrophoretic protein pattern showed any difference between the two groups. There were higher levels of inflammatory markers, interleukin-6 (IL6) and C-reactive protein (CRP) in EPO poor responder than good responder. The negative correlations between Hb and both IL6 and CRP levels in the present data remotely indicate a positive correlation between inflammatory markers and severity of anemia. A direct correlation between Hb and antioxidant enzymes (E-SOD and catalase) was noticed, while inverse correlation with E-MDA was recorded. The study proved that oral supplementation of vitamin C to ESRD patients might mitigate the previously elevated serum MDA level in these patients. PMID:27222740

  3. Treatment of anaemia in haemodialysis patients with erythropoietin: long-term effects on exercise capacity.

    PubMed

    Bárány, P; Freyschuss, U; Pettersson, E; Bergström, J

    1993-04-01

    1. The effects of correcting anaemia on exercise capacity were evaluated in 21 haemodialysis patients (aged 39 +/- 12 years) before starting treatment with recombinant human erythropoietin (Hb concentration, 73 +/- 10 g/l; total Hb, 59 +/- 12% of expected), after correction of the anaemia to a Hb concentration of 108 +/- 7 g/l and a total Hb 82 +/- 10% of expected, and in 13 of the patients after 12 months on maintenance recombinant human erythropoietin treatment (Hb concentration 104 +/- 14 g/l, total Hb 79 +/- 17% of expected). Fifteen healthy subjects (aged 41 +/- 9 years), who took no regular exercise, constituted the control group. Maximal exercise capacity was determined on a bicycle ergometer. Oxygen uptake, respiratory quotient, blood lactate concentration, heart rate and blood pressure were measured at rest and at maximal workload. 2. After 6 +/- 3 months on recombinant human erythropoietin, maximal exercise capacity increased from 108 +/- 27 W to 130 +/- 36W (P < 0.001) and the maximal oxygen uptake increased from 1.24 +/- 0.39 litres/min to 1.50 +/- 0.45 litres/min (P < 0.001). No significant changes in respiratory quotient (1.16 +/- 0.13 versus 1.18 +/- 0.13) and blood lactate concentration (4.0 +/- 1.8 versus 3.6 +/- 1.1 mmol/l) at maximal workload were observed, but the blood lactate concentration in the patients was significantly lower than that in the control subjects (6.7 +/- 2.3 mmol/l, P < 0.01). After the correction of anaemia, the aerobic power was still 38% lower in the patients than in the control subjects and 17% lower than the reference values.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Erythropoietin-producing cells in the liver of ICR-derived glomerulonephritis (ICGN) mice.

    PubMed

    Yamaguchi-Yamada, Misuzu; Akashi, Naotsugu; Goto, Yasufumi; Anan, Sayuri; Yamamoto, Yoshie; Ogura, Atsuo; Manabe, Noboru

    2006-01-01

    The ICR-derived glomerulonephritis (ICGN) mouse is an appropriate model for anemia associated with chronic renal disorder (CRD). Insufficient renal production of erythropoietin (EPO) induces the anemia associated with CRD. EPO mRNA is expressed in both kidneys and liver of progressing-stage ICGN mice. Hypoxic stimulation induced the EPO mRNA expression in the liver as well as in the kidneys of ICGN mice. The localization of EPO-producing cells in the liver remains controversial. Present study using an amplified in situ hybridization technique identified that nonparenchymal cells were the source of hepatic EPO production in ICGN mice under both normoxia and hypoxia.

  5. Preterm infant with a late presentation of blueberry muffin lesions secondary to recombinant erythropoietin.

    PubMed

    Rajpara, Anand; Blackmon, Joseph; Laarman, Rachel; Skaggs, Robert; Liolios, Ana; Lui, Deede; Fraga, Garth

    2013-09-14

    Our patient is a 26-week-old preterm female infant delivered by caesarean section secondary to severe maternal preeclampsia who had been receiving subcutaneous recombinant erythropoietin (r-EPO) for anemia of prematurity. At 8 weeks of age after 8 doses of r-EPO, the infant developed numerous non-blanching erythematous macules and patches located on the back, posterior shoulder, and posterior arms, concerning for late-onset blueberry muffin lesions. Biopsy of the lesions confirmed dermal hematopoiesis. After r-EPO was discontinued all skin lesions gradually resolved over a period of 2 weeks and never recurred.

  6. Engineering Administration.

    ERIC Educational Resources Information Center

    Naval Personnel Program Support Activity, Washington, DC.

    This book is intended to acquaint naval engineering officers with their duties in the engineering department. Standard shipboard organizations are analyzed in connection with personnel assignments, division operations, and watch systems. Detailed descriptions are included for the administration of directives, ship's bills, damage control, training…

  7. Administrative IT

    ERIC Educational Resources Information Center

    Grayson, Katherine, Ed.

    2006-01-01

    When it comes to Administrative IT solutions and processes, best practices range across the spectrum. Enterprise resource planning (ERP), student information systems (SIS), and tech support are prominent and continuing areas of focus. But widespread change can also be accomplished via the implementation of campuswide document imaging and sharing,…

  8. Database Administrator

    ERIC Educational Resources Information Center

    Moore, Pam

    2010-01-01

    The Internet and electronic commerce (e-commerce) generate lots of data. Data must be stored, organized, and managed. Database administrators, or DBAs, work with database software to find ways to do this. They identify user needs, set up computer databases, and test systems. They ensure that systems perform as they should and add people to the…

  9. Nonspecific shielding of unfavorable electrostatic intramolecular interactions in the erythropoietin native-state increase conformational stability and limit non-native aggregation

    PubMed Central

    Banks, Douglas D

    2015-01-01

    Previous equilibrium and kinetic folding studies of the glycoprotein erythropoietin indicate that sodium chloride increases the conformational stability of this therapeutically important cytokine, ostensibly by stabilizing the native-state [Banks DD, (2011) The Effect of Glycosylation on the Folding Kinetics of Erythropoietin. J Mol Biol 412:536–550]. The focus of the current report is to determine the underlying cause of the salt dependent increase in erythropoietin conformational stability and to understand if it has any impact on aggregation, an instability that remains a challenge to the biotech industry in maintaining the efficacy and shelf-life of protein therapeutics. Isothermal urea denaturation experiments conducted at numerous temperatures in the absence and presence of sodium chloride indicated that salt stabilizes erythropoietin primarily by increasing the difference in enthalpy between the native and unfolded sates. This result, and the finding that the salt induced increases in erythropoietin melting temperatures were independent of the identity of the salt cation and anion, indicates that salt likely increases the conformational stability of erythropoietin at neutral pH by nonspecific shielding of unfavorable electrostatic interaction(s) in the native-state. The addition of salt (even low concentrations of the strong chaotrope salt guanidinium hydrochloride) also exponentially decreased the initial rate of soluble erythropoietin non-native aggregation at 37 °C storage. PMID:25628168

  10. Ameliorative Effect of Recombinant Human Erythropoietin and Ischemic Preconditioning on Renal Ischemia Reperfusion Injury in Rats

    PubMed Central

    Elshiekh, Mohammed; Kadkhodaee, Mehri; Seifi, Behjat; Ranjbaran, Mina; Ahghari, Parisa

    2015-01-01

    Background: Ischemia-reperfusion (IR) injury is one of the most common causes of renal dysfunction. There is increasing evidence about the role of the reactive oxygen species (ROS) in these injuries and endogenous antioxidants seem to have an important role in decreasing the renal tissue injury. Objectives: The aim of this study was to compare the effect of recombinant human erythropoietin (EPO) and ischemic preconditioning (IPC) on renal IR injury. Materials and Methods: Twenty four male Wistar rats were allocated into four experimental groups: sham-operated, IR, EPO + IR, and IPC + IR. Rats were underwent 50 minutes bilateral ischemia followed by 24 hours reperfusion. Erythropoietin (5000 IU/kg, i.p) was administered 30 minutes before onset of ischemia. Ischemic preconditioning was performed by three cycles of 3 minutes ischemia followed by 3 minutes reperfusion. Plasma concentrations of urea and creatinine were measured. Kidney samples were taken for reactive oxidative species (ROS) measurement including superoxide dismutase (SOD) activity, glutathione (GSH) contents, and malondialdehyde (MDA) levels. Results: Compared to the sham group, IR led to renal dysfunction as evidenced by significantly higher plasma urea and creatinine. Treatment with EPO or IPC decreased urea, creatinine, and renal MDA levels and increased SOD activity and GSH contents in the kidney. Conclusions: Pretreatment with EPO and application of IPC significantly ameliorated the renal injury induced by bilateral renal IR. However, both treatments attenuated renal dysfunction and oxidative stress in kidney tissues. There were no significant differences between pretreatment with EPO or application of IPC. PMID:26866008

  11. A novel mutation of the erythropoietin receptor gene associated with primary familial and congenital polycythaemia.

    PubMed

    O'Rourke, Kacey; Fairbairn, David J; Jackson, Kathryn A; Morris, Kirk L; Tey, Siok-Keen; Kennedy, Glen A

    2011-04-01

    Primary familial and congenital polycythaemia (PFCP) is a rare form of inherited erythrocytosis caused by heterozygous mutations in the erythropoietin receptor gene (EPOR). We present a novel mutation in the EPOR in a 15-year-old male who was referred to our clinic for investigation of a persistently elevated haemoglobin level. A significant family history of unexplained erythrocytosis spanning four generations of the patient's family was established. The family history was also significant for an apparent increased rate of cerebrovascular disease in individuals with erythrocytosis. The mutation detected in our patient resides in exon 8 of EPOR, similar to all other EPOR mutations responsible for PFCP. These mutations result in truncation of the cytoplasmic domain of the receptor and impair down-regulation of signalling via the erythropoietin receptor (EPOR). Clinical manifestations in published cases have varied widely and there is a paucity of firm recommendations regarding the management of affected patients. Given the strong family history of complications attributable to erythrocytosis we have recommended venesection with a haematocrit target of ≤0.45 for our patient.

  12. Erythropoietin enhances whole body lipid oxidation during prolonged exercise in humans.

    PubMed

    Caillaud, Corinne; Connes, Philippe; Ben Saad, Helmi; Mercier, Jacques

    2015-03-01

    Animal studies have suggested that erythropoietin, besides its well-known hematopoietic effects, can modulate metabolism and prevent fat accumulation. We investigated the effects of repeated injections of recombinant human erythropoietin (EPO) on the balance of substrate oxidation during aerobic exercise in humans. Twelve healthy aerobically trained males received subcutaneously either moderate dose of EPO (50 U/kg, EPO) or saline injections (NaCl 0.9 %, control) three times a week for 4 weeks. Body weight, % fat, maximal aerobic capacity, and substrate utilization during exercise were assessed before and after treatment, while hemoglobin and hematocrit were monitored regularly during the treatment. Carbohydrate and fat oxidation were evaluated via indirect calorimetry, during a submaximal exercise performed at 75 % of the participants' maximal aerobic capacity (V̇(O2max)) for 60 min. Results showed that 4 weeks of EPO treatment significantly enhanced fat oxidation (+56 % in EPO versus -9 % in control) during exercise, independent of its effects on hematological parameters or V̇(O2max). This study shows that EPO can modulate substrate utilization during exercise, leading to enhanced fat utilization and lower use of carbohydrates. This opens new research directions exploring whether systemic EPO levels, in physiological conditions, participate to the modulation of fat oxidation.

  13. Exploring Erythropoietin and G-CSF Combination Therapy in Chronic Stroke Patients

    PubMed Central

    Shin, Yoon-Kyum; Cho, Sung-Rae

    2016-01-01

    Erythropoietin (EPO) and granulocyte-colony stimulating factor (G-CSF) are known to have neuroprotective actions. Based on previous reports showing the synergistic effects of EPO+G-CSF combination therapy in experimental models, we investigated the safety of EPO+G-CSF combination therapy in patients with chronic stroke. In a pilot study, 3 patients were treated with EPO and G-CSF for 5 consecutive days, with follow-up on day 30. In an exploratory double-blind study, 6 patients were allocated to treatment with either EPO+G-CSF or placebo. Treatment was applied once a day for 5 days per month over 3 months. Participants were followed up for 6 months. To substantiate safety, vital signs, adverse events, and hematological values were measured on days 0, 5, and 30 in each cycle and on day 180. Functional outcomes were determined on day 0 and 180. In the laboratory measurements, EPO+G-CSF combination therapy significantly elevated erythropoietin, CD34+ hematopoietic stem cells, white blood cells, and neutrophils on day 5 of each cycle. There were no observations of serious adverse events. In the functional outcomes, the grip power of the dominant hand was increased in the EPO+G-CSF treatment group. In conclusion, this exploratory study suggests a novel strategy of EPO+G-CSF combination therapy for stroke patients. PMID:27043535

  14. [Infantile pyknocytosis: A cause of noenatal hemolytic anemia. Is recombinant erythropoietin an alternative to transfusion?].

    PubMed

    Bagou, M; Rolland, E; Gay, C; Patural, H

    2016-01-01

    Infantile pyknocytosis is a neonatal hemolytic disorder which causes anemia and icterus and is characterized by the presence of an increased number of distorted red blood cells called pyknocytes. Resolution spontaneously occurs in the first semester of life. It has been generally described as a rare entity, with an occasional family history. We report seven cases of infantile pyknocytosis observed in our hospital in 3 years. Most of the infants presented with hemolytic icterus and profound anemia that was reaching its peak by the 3rd week of life. Three neonates received one to three red blood cell transfusions, according to former recommendations. However, the following four received a treatment with recombinant erythropoietin administered subcutaneously. Only one of these four cases required a transfusion. All of them were free of hematological disease 2-3 months after completion of treatment. Infantile pyknocytosis is a recognized cause of neonatal hemolytic anemia, which requires careful examination of red cell morphology on a peripheral blood smear. The cause of this transient disorder remains unknown. Our observations show that recombinant erythropoietin therapy is effective in treating infantile pyknocytosis and increases the reticulocyte response, thus improving the hemoglobin level.

  15. Erythropoietin and IGF-1 signaling synchronize cell proliferation and maturation during erythropoiesis

    PubMed Central

    Kadri, Zahra; Lefevre, Carine; Goupille, Olivier; Penglong, Tipparat; Granger-Locatelli, Marine; Fucharoen, Suthat; Maouche-Chretien, Leila; Leboulch, Philippe; Chretien, Stany

    2015-01-01

    Tight coordination of cell proliferation and differentiation is central to red blood cell formation. Erythropoietin controls the proliferation and survival of red blood cell precursors, while variations in GATA-1/FOG-1 complex composition and concentrations drive their maturation. However, clear evidence of cross-talk between molecular pathways is lacking. Here, we show that erythropoietin activates AKT, which phosphorylates GATA-1 at Ser310, thereby increasing GATA-1 affinity for FOG-1. In turn, FOG-1 displaces pRb/E2F-2 from GATA-1, ultimately releasing free, proproliferative E2F-2. Mice bearing a Gata-1S310A mutation suffer from fatal anemia when a compensatory pathway for E2F-2 production involving insulin-like growth factor-1 (IGF-1) signaling is simultaneously abolished. In the context of the GATA-1V205G mutation resulting in lethal anemia, we show that the Ser310 cannot be phosphorylated and that constitutive phosphorylation at this position restores partial erythroid differentiation. This study sheds light on the GATA-1 pathways that synchronize cell proliferation and differentiation for tissue homeostasis. PMID:26680303

  16. Erythropoietin therapy after allogeneic hematopoietic cell transplantation: a prospective, randomized trial.

    PubMed

    Jaspers, Aurélie; Baron, Frédéric; Willems, Evelyne; Seidel, Laurence; Hafraoui, Kaoutar; Vanstraelen, Gaetan; Bonnet, Christophe; Beguin, Yves

    2014-07-03

    We conducted a prospective randomized trial to assess hemoglobin (Hb) response to recombinant human erythropoietin (rhEPO) therapy after hematopoietic cell transplantation (HCT). Patients (N = 131) were randomized (1:1) between no treatment (control arm) or erythropoietin at 500 U/kg per week (EPO arm). Patients were also stratified into 3 cohorts: patients undergoing myeloablative HCT with rhEPO to start on day (D)28, patients given nonmyeloablative HCT (NMHCT) with rhEPO to start on D28, and patients also given NMHCT but with rhEPO to start on D0. The proportion of complete correctors (ie, Hb ≥13 g/dL) before D126 posttransplant was 8.1% in the control arm (median not reached) and 63.1% in the EPO arm (median, 90 days) (P < .001). Hb levels were higher and transfusion requirements decreased (P < .001) in the EPO arm, but not during the first month in the nonmyeloablative cohort starting rhEPO on D0. There was no difference in rates of thromboembolic events or other complications between the 2 arms. This is the first randomized trial to demonstrate that rhEPO therapy hastens erythroid recovery and decreases transfusion requirements when started one month after allogeneic HCT. There was no benefit to start rhEPO earlier after NMHCT.

  17. Erythropoietin administration alone or in combination with endurance training affects neither skeletal muscle morphology nor angiogenesis in healthy young men.

    PubMed

    Larsen, Mads S; Vissing, Kristian; Thams, Line; Sieljacks, Peter; Dalgas, Ulrik; Nellemann, Birgitte; Christensen, Britt

    2014-10-01

    The aim was to investigate the ability of an erythropoiesis-stimulating agent (ESA), alone or in combination with endurance training, to induce changes in human skeletal muscle fibre and vascular morphology. In a comparative study, 36 healthy untrained men were randomly dispersed into the following four groups: sedentary-placebo (SP, n = 9); sedentary-ESA (SE, n = 9); training-placebo (TP, n = 10); or training-ESA (TE, n = 8). The ESA or placebo was injected once weekly. Training consisted of progressive bicycling three times per week for 10 weeks. Before and after the intervention period, muscle biopsies and magnetic resonance images were collected from the thigh muscles, blood was collected, body composition measured and endurance exercise performance evaluated. The ESA treatment (SE and TE) led to elevated haematocrit, and both ESA treatment and training (SE, TP and TE) increased maximal O2 uptake. With regard to skeletal muscle morphology, TP alone exhibited increases in whole-muscle cross-sectional area and fibre diameter of all fibre types. Also exclusively for TP was an increase in type IIa fibres and a corresponding decrease in type IIx fibres. Furthermore, an overall training effect (TP and TE) was statistically demonstrated in whole-muscle cross-sectional area, muscle fibre diameter and type IIa and type IIx fibre distribution. With regard to muscle vascular morphology, TP and TE both promoted a rise in capillary to muscle fibre ratio, with no differences between the two groups. There were no effects of ESA treatment on any of the muscle morphological parameters. Despite the haematopoietic effects of ESA, we provide novel evidence that endurance training rather than ESA treatment induces adaptational changes in angiogenesis and muscle morphology.

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

    PubMed Central

    Marcon, Raphael Martus; Cristante, Alexandre Fogaça; de Barros Filho, Tarcísio Eloy Pessoa; Ferreira, Ricardo; dos Santos, Gustavo Bispo

    2016-01-01

    OBJECTIVE: To evaluate the functional and histological effects of ganglioside G(M1) and erythropoietin after experimental spinal cord contusion injury. METHODS: Fifty male Wistar rats underwent experimental spinal cord lesioning using an NYU-Impactor device and were randomly divided into the following groups, which received treatment intraperitoneally. The G(M1) group received ganglioside G(M1) (30 mg/kg); the erythropoietin group received erythropoietin (1000 IU/kg); the combined group received both drugs; and the saline group received saline (0.9%) as a control. A fifth group was the laminectomy group, in which the animals were subjected to laminectomy alone, without spinal lesioning or treatment. The animals were evaluated according to the Basso, Beattie and Bresnahan (BBB) scale, motor evoked potential recordings and, after euthanasia, histological analysis of spinal cord tissue. RESULTS: The erythropoietin group had higher BBB scores than the G(M1) group. The combined group had the highest BBB scores, and the saline group had the lowest BBB scores. No significant difference in latency was observed between the three groups that underwent spinal cord lesioning and intervention. However, the combined group showed a significantly higher signal amplitude than the other treatment groups or the saline group (p<0.01). Histological tissue analysis showed no significant difference between the groups. Axonal index was significantly enhanced in the combined group than any other intervention (p<0.01). CONCLUSION: G(M1) and erythropoietin exert therapeutic effects on axonal regeneration and electrophysiological and motor functions in rats subjected to experimental spinal cord lesioning and administering these two substances in combination potentiates their effects. PMID:27438570

  19. Revisiting emergency anti-apoptotic cytokinotherapy: erythropoietin synergizes with stem cell factor, FLT-3 ligand, trombopoietin and interleukin-3 to rescue lethally-irradiated mice.

    PubMed

    Drouet, Michel; Grenier, Nancy; Hérodin, Francis

    2012-06-01

    We have re-evaluated the benefit of using erythropoietin (Epo) as a pleiotropic cytokine to counteract hematological and extra-hematological toxicity following lethal irradiation. B6D2F1 mice were exposed to a dose of 9 Gy gamma radiation resulting in 90% mortality at 30 days, and then injected with stem cell factor, FLT-3 ligand, thrombopoietin and interleukin-3 [i.e. SFT3] at two and 24 hours with or without Epo (1,000 IU/kg) at 2 hours and day 8. As controls, two groups of irradiated mice were given only Epo or Phosphate-buffered saline. Epo synergized with SFT3 to rescue lethally-irradiated mice from radiation-induced death (survival: 60%, 95% and 5% respectively for SFT3, SFT3+Epo and controls at 30 days, p<0.05), whereas Epo alone exhibited no protective effect. Hematopoietic parameters did not differ significantly between SFT3 and SFT3+Epo groups during the animal death period. Some beneficial effects on gastro-intestinal toxicity were noticed following administration of Epo, although lung, liver and kidney were not protected. Further studies are necessary to understand fully the mechanisms involved in these effects of Epo in order to optimize treatment with cytokines following high-dose irradiation.

  20. Cellular and molecular mechanisms regulating the hepatic erythropoietin expression during acute-phase response: a role for IL-6.

    PubMed

    Ramadori, Pierluigi; Ahmad, Ghayyor; Ramadori, Giuliano

    2010-09-01

    The source of circulating erythropoietin (EPO), the mediators and the mechanisms involved in the upregulation of EPO gene expression during acute-phase reaction are still poorly understood. Acute-phase reaction was induced by either intramuscular turpentine oil (TO) or intraperitoneal lipopolysaccharide (LPS) administration into wild-type and interleukin (IL)-6 knockout (KO) mice. Animals were killed at different time points and blood, liver and muscle tissue were collected. Serum levels of EPO were measured by enzyme-linked immunoadsorbent assay; liver and injured muscle samples were processed for RNA isolation and for protein analysis. EPO, hypoxia-inducible factors 1alpha and 2alpha (HIF-1alpha and HIF-2alpha) mRNA were analyzed by RT-PCR and the protein levels were analyzed by western blot and electrophoretic mobility shift assay. HIF-1alpha and HIF-2alpha localization was performed through immunofluorescence staining. EPO, HIF-1 and HIF-2 gene and protein expression levels were also analyzed in isolated mouse hepatocytes after stimulation with IL-6. In the wild-type animals, EPO serum levels increased dramatically at 12 h after the insults together with the hepatic gene expression. In TO-treated animals, the EPO gene expression reached an 8.2-fold increase at 12 h, and in LPS-treated mice a similar induction was recorded at 6 h (about 4.5-fold increase). In the IL-6KO strain, the upregulation after the inflammatory stimuli was much lower (only 2.0-fold increase). A progressive upregulation of HIF-1alpha and HIF-2alpha was detectable until 6 h after the insults, but only HIF-1alpha upregulation was reduced in IL-6KO mice. In isolated hepatocytes, stimulation with a single dose of IL-6 induced a nuclear accumulation of HIF-1alpha, in parallel with an increase of EPO mRNA. No effect on HIF-2alpha expression was found. IL-6 appears to be the main regulator of EPO gene expression and a major contributor for HIF-1alpha induction in hepatocytes and Kupffer cells

  1. Effect of an intravenous iron dextran regimen on iron stores, hemoglobin, and erythropoietin requirements in hemodialysis patients.

    PubMed

    Park, L; Uhthoff, T; Tierney, M; Nadler, S

    1998-05-01

    Iron deficiency is a common cause of delayed or diminished response to erythropoietin (EPO) in hemodialysis patients. Although oral iron is often prescribed to replete iron stores, this approach to iron supplementation may not be adequate with chronic EPO therapy. Intravenous (IV) iron dextran may be an effective alternative approach to replete iron stores and may facilitate more cost-effective use of EPO. The purpose of this study was to evaluate an IV iron dextran regimen that consisted of a loading dose phase followed by monthly maintenance doses of iron dextran. The effect of this regimen on iron stores, hemoglobin, and EPO doses was evaluated. This was an open prospective study in adult hemodialysis patients who were iron deficient as defined by a serum ferritin less than 100 ng/mL or transferrin saturation (TSAT) of less than 20%. Patients were loaded with 1 g iron dextran in five divided doses and then received monthly maintenance doses of 100 mg for the 4-month study period. Values of serum ferritin, TSAT, hemoglobin, and EPO dose were followed for the 4-month study period. Thirty hemodialysis patients receiving EPO were identified as being iron deficient and were enrolled in the study. The mean serum ferritin increased significantly from 49 ng/mL at baseline to 225 ng/mL at the end of the study period (P < 0.0001). Mean TSAT also increased significantly from 27% to 33% (P = 0.002). Values for hemoglobin did not change significantly during the study period; however, there was a significant reduction in EPO dose from a mean baseline dose of 112 U/kg/wk to 88 U/kg/wk at the end of the study period (P = 0.009). Seventeen patients experienced an increase in hemoglobin or a decrease in EPO dose. Economic analysis showed that approximately $580 (Cdn) per patient per year could be saved by use of IV iron dextran. The administration of the IV iron dextran regimen in the iron-deficient hemodialysis population was effective at repleting and maintaining iron stores

  2. Chemical synthesis of erythropoietin glycoforms for insights into the relationship between glycosylation pattern and bioactivity

    PubMed Central

    Murakami, Masumi; Kiuchi, Tatsuto; Nishihara, Mika; Tezuka, Katsunari; Okamoto, Ryo; Izumi, Masayuki; Kajihara, Yasuhiro

    2016-01-01

    The role of sialyloligosaccharides on the surface of secreted glycoproteins is still unclear because of the difficulty in the preparation of sialylglycoproteins in a homogeneous form. We selected erythropoietin (EPO) as a target molecule and designed an efficient synthetic strategy for the chemical synthesis of a homogeneous form of five EPO glycoforms varying in glycosylation position and the number of human-type biantennary sialyloligosaccharides. A segment coupling strategy performed by native chemical ligation using six peptide segments including glycopeptides yielded homogeneous EPO glycopeptides, and folding experiments of these glycopeptides afforded the correctly folded EPO glycoforms. In an in vivo erythropoiesis assay in mice, all of the EPO glycoforms displayed biological activity, in particular the EPO bearing three sialyloligosaccharides, which exhibited the highest activity. Furthermore, we observed that the hydrophilicity and biological activity of the EPO glycoforms varied depending on the glycosylation pattern. This knowledge will pave the way for the development of homogeneous biologics by chemical synthesis. PMID:26824070

  3. Cost minimization analysis of preoperative erythropoietin vs autologous and allogeneic blood donation in total joint arthroplasty.

    PubMed

    Green, William Scott; Toy, Pearl; Bozic, Kevin J

    2010-01-01

    Autologous blood donation and erythropoietin (EPO) have been shown to be effective in reducing allogeneic blood transfusion, but the cost-effectiveness of these interventions remains unclear. A cost minimization analysis was performed, comparing the total costs of allogeneic blood transfusion strategy and autologous and allogeneic blood transfusion strategy for 161 primary total hip arthroplasty (THA) and 195 total knee arthroplasty (TKA) patients. An EPO cost minimization model was constructed using a previously published algorithm for blood management after total joint arthroplasty. The least costly strategy was autologous blood donation in combination with allogeneic blood for THA and TKA patients at $856 and $892 per patient, respectively. The most costly strategy was allogeneic only at $1769 and $1352 per THA and TKA patient, respectively. The EPO strategy model predicted costs similar to the autologous and allogeneic. A strategy that combines autologous blood donation with EPO for patients who cannot donate autologous blood may provide the greatest cost savings and minimize allogeneic blood transfusion.

  4. Undifferentiated sarcoma of the liver: a case study of an erythropoietin-secreting tumor.

    PubMed

    Lin, JoAnn M; Heath, Jonathon E; Twaddell, William S; Castellani, Rudy J

    2014-09-01

    Undifferentiated embryonal sarcoma of the liver (UESL) is an uncommon hepatic tumor usually found in children, with rare cases reported in adults. We present a case of a 53-year-old woman with an undifferentiated sarcoma of the liver (USL), which resembles UESL, who initially presented with a markedly elevated hematocrit (61.2%). Cytogenetic studies for polycythemia vera were negative, but the patient's erythropoietin (EPO) was elevated. A computed tomography scan and subsequent partial hepatectomy revealed a well-circumscribed, partially cystic mass in the right lobe of the liver measuring 34 cm. Following surgery, the patient's EPO level and hematocrit dropped to within normal range and remained so for 1 year, at which point it rose again. A subsequent magnetic resonance imaging scan showed a liver mass at the previous resection margin, consistent with a recurrence. In this case study, we describe the first reported USL resembling an UESL that secretes EPO, which was a useful marker of tumor recurrence.

  5. Erythropoietin and thrombopoietin mimetics: Natural alternatives to erythrocyte and platelet disorders.

    PubMed

    Gutti, Usha; Pasupuleti, Satya Ratan; Sahu, Itishri; Kotipalli, Aneesh; Undi, Ram Babu; Kandi, Ravinder; Venakata Saladi, Raja Gopal; Gutti, Ravi Kumar

    2016-12-01

    Erythropoietin (EPO) and thrombopoietin (TPO) plays a major role in the regulation of hematopoietic development. Though, blood transfusion was the most widely used method to treat low blood count, over the years with advancements in recombinant technology and drug designing, the EPO and TPO mimetics are dominating the therapeutics industry. On the other hand, the recombinant human EPO and TPO are associated either with reduced half-life or immune reactions. The restoration of alternate medicine in recent years has the hope to overcome limitations associated with recombinant technology, to treat various disorder including blood diseases, with low to no side effects. The work in recent years on plant derived mimetics suggests a paradigm shift in the way diseases are treated. Here, we are providing a comprehensive review on the EPO and TPO recombinant counterparts and synthetic mimetics studied till date with a focus on the need for more natural alternatives.

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

    PubMed Central

    2012-01-01

    There is a plethora of experimental data on the potential therapeutic benefits of recombinant human erythropoietin (rhEPO) and its synthetic derivatives in critical care medicine, in particular in ischemia/reperfusion injury. Most of the recent clinical trials have not shown clear benefits, and, in some patients, EPO-aggravated morbidity and mortality was even reported. Treatment with rhEPO has been successfully used in patients with anemia resulting from chronic kidney disease, but even a subset of this patient population does not adequately respond to rhEPO therapy. The following viewpoint uses rhEPO as an example to highlight the possible pitfalls in current practice using young healthy animals for the evaluation of therapies to treat patients of variable age and underlying chronic co-morbidity. PMID:23016869

  7. Expression and characterization of erythropoietin receptors on normal human bone marrow cells

    SciTech Connect

    Hoshino, S.; Teramura, M.; Takahashi, M.; Motoji, T.; Oshimi, K.; Ueda, M.; Mizoguchi, H.

    1989-05-01

    We studied the specific binding of /sup 125/I-labeled bioactive recombinant human erythropoietin (Epo) to human bone marrow mononuclear cells (BMNC) obtained from normal subjects. The /sup 125/I-labeled Epo bound specifically to the BMNC. Scatchard analysis of the data showed two classes of binding sites; one high affinity (Kd 0.07 nM) and the other low affinity (Kd 0.38 nM). The number of Epo binding sites per BMNC was 46 +/- 16 high-affinity receptors and 91 +/- 51 low-affinity receptors. The specific binding was displaced by unlabeled Epo, but not by other growth factors. Receptor internalization was observed significantly at 37 degrees C, but was prevented by the presence of 0.2% sodium azide. These findings indicate that human BMNC possess two classes of specific Epo receptors with characteristics of a hormone-receptor association.

  8. Chemical synthesis of erythropoietin glycoforms for insights into the relationship between glycosylation pattern and bioactivity.

    PubMed

    Murakami, Masumi; Kiuchi, Tatsuto; Nishihara, Mika; Tezuka, Katsunari; Okamoto, Ryo; Izumi, Masayuki; Kajihara, Yasuhiro

    2016-01-01

    The role of sialyloligosaccharides on the surface of secreted glycoproteins is still unclear because of the difficulty in the preparation of sialylglycoproteins in a homogeneous form. We selected erythropoietin (EPO) as a target molecule and designed an efficient synthetic strategy for the chemical synthesis of a homogeneous form of five EPO glycoforms varying in glycosylation position and the number of human-type biantennary sialyloligosaccharides. A segment coupling strategy performed by native chemical ligation using six peptide segments including glycopeptides yielded homogeneous EPO glycopeptides, and folding experiments of these glycopeptides afforded the correctly folded EPO glycoforms. In an in vivo erythropoiesis assay in mice, all of the EPO glycoforms displayed biological activity, in particular the EPO bearing three sialyloligosaccharides, which exhibited the highest activity. Furthermore, we observed that the hydrophilicity and biological activity of the EPO glycoforms varied depending on the glycosylation pattern. This knowledge will pave the way for the development of homogeneous biologics by chemical synthesis.

  9. Is erythropoietin a worthy candidate for traumatic brain injury or are we heading the wrong way?

    PubMed Central

    Grasso, Giovanni; Alafaci, Concetta; Ghezzi, Pietro

    2016-01-01

    Traumatic brain injury (TBI) is a leading cause of death and disability in the modern society. Although primary prevention is the only strategy that can counteract the primary brain damage, numerous preclinical studies have been accumulated in order to find therapeutic strategies against the secondary damage. In this scenario erythropoietin (EPO) has been shown to be a promising candidate as neuroprotective agent. A recent clinical trial, however, has shown that EPO has not an overall effect on outcomes following TBI thus renewing old concerns.  However, the results of a prespecified sensitivity analysis indicate that the effect of EPO on mortality remains still unclear. In the light of these observations, further investigations are needed to resolve doubts on EPO effectiveness in order to provide a more solid base for tailoring conclusive clinical trials. PMID:27239280

  10. Antiepoetin antibody-related pure red cell aplasia: successful remission with cessation of recombinant erythropoietin alone.

    PubMed

    Katagiri, Daisuke; Shibata, Maki; Katsuki, Takashi; Masumoto, Shoichi; Katsuma, Ai; Minami, Eri; Hoshino, Taro; Inoue, Tsuyoshi; Tada, Manami; Hinoshita, Fumihiko

    2010-10-01

    An elderly patient with pure red cell aplasia (PRCA) with antierythropoietin (anti-EPO) antibodies is described. PRCA due to alloimmunization is a rare and severe complication of recombinant human erythropoietin (rHu-EPO) therapy. Most reported patients with PRCA were cured primarily by immunosuppressive drug therapy. The patient in this case, however, did not want to receive any immunosuppressive drugs. Therefore, rHu-EPO injection was simply discontinued, the severe anemia gradually improved, and the hemoglobin approached normal range. This case is very rare and significant in that there have been few such elderly patients with rHu-EPO-induced PRCA in whom PRCA remission was achieved, with decreasing antibody titers, after cessation of rHu-EPO alone. Further cases are needed to assess how PRCA should be treated in patients with anti-EPO antibodies.

  11. Isoelectric profiles of human erythropoietin are different in serum and urine.

    PubMed

    Lasne, Françoise; Martin, Laurent; Martin, Jean Antoine; de Ceaurriz, Jacques

    2007-08-01

    By adding a step of immunoaffinity to the method we had previously developed for analysing erythropoietin (EPO) in urine, we were able to study the isoelectric profiles of this hormone in human serum samples. This method was sensitive enough to investigate samples presenting physiological levels of this hormone. Comparison with the corresponding profiles in urine showed that natural EPO was systematically more acidic in urine. The acidification process, which was not patent in the non-human primate Cynomolgus macaque, clearly also affected recombinant EPO when injected into humans. This process was unrelated to any enzymatic activity in urine since the incubation of natural or recombinant EPO in urine induced no transformation of their isoelectric profiles. The nature and mechanism of the structural modifications occurring during the renal handling of this hormone remain to be investigated.

  12. Effects of exercise on the secondary blood markers commonly used to suspect erythropoietin doping.

    PubMed

    Robinson, Neil; Saugy, Martial; Mangin, Patrice

    2003-01-01

    Numerous trials have reported that some haematological and biochemical parameters could be put together and be used to detect and fight recombinant erythropoietin doping. Unfortunately, none of the studies mentioned the necessity of taking pre-analytical precautions to avoid possible suspicious results coming from major plasma volume changes caused notably by dehydration. Therefore we studied the behaviour of the most common secondary blood markers before and after a strenuous physical activity to find out how reliable these parameters were. The soluble transferrin receptor and the haemoglobin concentrations as well as the haematocrit level increased significantly after effort, whereas the plasma EPO concentration and the reticulocyte count remained constant. On the other hand, if the values were corrected for haemoconcentration, the soluble transferrin receptor concentration remained stable.

  13. Gel electrophoretic methods for the analysis of biosimilar pharmaceuticals using the example of recombinant erythropoietin.

    PubMed

    Reichel, Christian; Thevis, Mario

    2013-03-01

    Due to their versatility and cost-effectiveness, gel electrophoretic methods provide an important set of tools for the analysis of therapeutic proteins. As an increasing number of biosimilar pharmaceuticals are entering the market, techniques are required that allow reliable demonstration of comparability of these products with the reference products. Isoelectric focusing, SDS-PAGE, native PAGE and 2D electrophoresis (2D-PAGE) have been frequently applied for this purpose. Supplementary techniques are fluorophore-assisted carbohydrate electrophoresis and sarcosyl-PAGE. Of additional importance is the comparison of recombinant with endogenously synthesized glycoproteins. Reagent array analysis combined with SDS-PAGE and western blotting proved especially useful for this purpose. As an example for the application of these methods, the analysis of recombinant originator erythropoietins and some of their biosimilar counterparts is described.

  14. Role of cytochrome P sub 450 in the control of the production of erythropoietin

    SciTech Connect

    Fandrey, J.; Seydel, F.P.; Siegers, C.P.; Jelkmann, W. )

    1990-01-01

    Effects of agents affecting cytochrome P{sub 450} were studied on the production of erythropoietin (Epo) in cultures of the human hepatoma cell line HepG2. Epo was measured by radioimmunoassay of the culture media after 24 h of incubation. The addition of phenobarbital or 3-methylcholanthrene, which induce cytochrome P{sub 450}, significantly enhanced the formation of Epo. Likewise, the thyroid hormones T{sub 3} and T{sub 4} stimulated the rate of the production of Epo. On the other hand, the formation of Epo was lowered following the addition of diethyl-dithiocarbamate or cysteamine chloride, which inhibit cytochrome P{sub 450}. These findings support the idea that O{sub 2} sensitive hemoproteins of the microsomal mixed-functional oxidases play a role in the control of the synthesis of Epo.

  15. The SH2B1 adaptor protein associates with a proximal region of the erythropoietin receptor.

    PubMed

    Javadi, Mojib; Hofstätter, Edda; Stickle, Natalie; Beattie, Bryan K; Jaster, Robert; Carter-Su, Christin; Barber, Dwayne L

    2012-07-27

    Gene targeting experiments have shown that the cytokine erythropoietin (EPO), its cognate erythropoietin receptor (EPO-R), and associated Janus tyrosine kinase, JAK2, are all essential for erythropoiesis. Structural-functional and murine knock-in experiments have suggested that EPO-R Tyr-343 is important in EPO-mediated mitogenesis. Although Stat5 binds to EPO-R phosphotyrosine 343, the initial Stat5-deficient mice did not have profound erythroid abnormalities suggesting that additional Src homology 2 (SH2) domain-containing effectors may bind to EPO-R Tyr-343 and couple to downstream signaling pathways. We have utilized cloning of ligand target (COLT) screening to demonstrate that EPO-R Tyr(P)-343 and Tyr(P)-401 bind to the SH2 domain-containing adaptor protein SH2B1β. Immunoprecipitation and in vitro mixing experiments reveal that EPO-R binds to SH2B1 in an SH2 domain-dependent manner and that the sequence that confers SH2B1 binding to the EPO-R is pYXXL. Previous studies have shown that SH2B1 binds directly to JAK2, but we show that in hematopoietic cells, SH2B1β preferentially associates with the EPO-R. SH2B1 is capable of constitutive association with EPO-R, which is necessary for its optimal SH2-dependent recruitment to EPO-R-Tyr(P)-343/Tyr(P)-401. We also demonstrate that SH2B1 is responsive to EPO stimulation and becomes phosphorylated, most likely on serines/threonines, in an EPO dose- and time-dependent manner. In the absence of SH2B1, we observe enhanced activation of signaling pathways downstream of the EPO-R, indicating that SH2B1 is a negative regulator of EPO signaling.

  16. Neuroprotective effects of erythropoietin posttreatment against kainate-induced excitotoxicity in mixed spinal cultures.

    PubMed

    Yoo, Jong Yoon; Won, You Jin; Lee, Jong Hwan; Kim, Jong Uk; Sung, In Young; Hwang, Seung Jun; Kim, Mi Jung; Hong, Hea Nam

    2009-01-01

    Although the neuroprotective effects of erythropoietin (EPO) preconditioning are well known, the potential of postapplied EPO to protect neurons against excitotoxic injury has not been clearly established. Here we show that kainate (KA)-induced excitotoxicity, which plays a key role in secondary spinal cord injury, decreased neuron survival, inhibited neurite extension, and significantly reduced the expression of erythropoietin receptors (EpoR) in cultured spinal neurons. Posttreatment with EPO for 48 hr protected neurons against KA-induced injury, opposing KA-induced apoptosis and promoting regrowth of motoneuron neurites. These neuroprotective effects were paralleled by a restoration of EpoR expression. The importance of the EpoR signaling pathway was demonstrated using an EpoR blocking antibody, which neutralized the neuroprotective action of EPO posttreatment and prevented EPO-induced increases in EpoR expression. We also found that up-regulated EpoR stimulated the Janus kinase 2 (JAK2) pathway, which is known to facilitate neuronal growth and neurite regeneration. Although EPO posttreatment modestly attenuated KA-induced reactive gliosis in mixed neuron-glial cultures, blocking EpoR activity did not alter glial fibrillary acidic protein expression or astrocyte proliferation. In conclusion, 48 hr treatment with EPO following KA exposure induced EpoR-dependent protection against excitotoxic injury, demonstrating that preconditioning is not a prerequisite for neuroprotection by EPO. The neuroprotective effects of EPO posttreatment were mediated by an EpoR-dependent signaling pathway that possibly involves JAK2. The neuroprotective effect of EPO posttreatment against KA excitotoxicity appears to reflect direct effects on neurons and not indirect effects mediated by astrocytes.

  17. Erythropoietin is involved in the angiogenic potential of bone marrow macrophages in multiple myeloma.

    PubMed

    De Luisi, Annunziata; Binetti, Laura; Ria, Roberto; Ruggieri, Simona; Berardi, Simona; Catacchio, Ivana; Racanelli, Vito; Pavone, Vincenzo; Rossini, Bernardo; Vacca, Angelo; Ribatti, Domenico

    2013-10-01

    Erythropoietin (Epo) is the crucial cytokine regulator of red blood cell production, and recombinant human erythropoietin (rHuEpo) is widely used in clinical practice for the treatment of anemia, primarily in kidney disease and in cancer. Increasing evidence suggests several biological roles for Epo and its receptor, Epo-R, unrelated to erythropoiesis, including angiogenesis. Epo-R has been found expressed in various non-haematopoietic cells and tissues, and in cancer cells. Here, we detected the expression of Epo-R in bone marrow-derived macrophages (BMMAs) from multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS) patients and assessed whether Epo/Epo-R axis plays a role in MM macrophage-mediated angiogenesis. We found that Epo-R is over-expressed in BMMAs from MM patients with active disease compared to MGUS patients. The treatment of BMMAs with rHuEpo significantly increased the expression and secretion of key pro-angiogenic mediators, such as vascular endothelial growth factor, hepatocyte growth factor and monocyte chemotactic protein (MCP-1/CCL-2), through activation of JAK2/STAT5 and PI3 K/Akt pathways. In addition, the conditioned media harvested from rHuEpo-treated BMMAs enhanced bone marrow-derived endothelial cell migration and capillary morphogenesis in vitro, and induced angiogenesis in the chorioallantoic membrane of chick embryos in vivo. Furthermore, we found an increase in the circulating levels of several pro-angiogenic cytokines in serum of MM patients with anemia under treatment with Epo. Our findings highlight the direct effect of rHuEpo on macrophage-mediated production of pro-angiogenic factors, suggesting that Epo/Epo-R pathway may be involved in the regulation of angiogenic response occurring in MM.

  18. Transplantation of genetically engineered cardiac fibroblasts producing recombinant human erythropoietin to repair the infarcted myocardium

    PubMed Central

    Ruvinov, Emil; Sharabani-Yosef, Orna; Nagler, Arnon; Einbinder, Tom; Feinberg, Micha S; Holbova, Radka; Douvdevani, Amos; Leor, Jonathan

    2008-01-01

    Background Erythropoietin possesses cellular protection properties. The aim of the present study was to test the hypothesis that in situ expression of recombinant human erythropoietin (rhEPO) would improve tissue repair in rat after myocardial infarction (MI). Methods and results RhEPO-producing cardiac fibroblasts were generated ex vivo by transduction with retroviral vector. The anti-apoptotic effect of rhEPO-producing fibroblasts was evaluated by co-culture with rat neonatal cardiomyocytes exposed to H2O2-induced oxidative stress. Annexin V/PI assay and DAPI staining showed that compared with control, rhEPO forced expression markedly attenuated apoptosis and improved survival of cultured cardiomyocytes. To test the effect of rhEPO on the infarcted myocardium, Sprague-Dawley rats were subjected to permanent coronary artery occlusion, and rhEPO-producing fibroblasts, non-transduced fibroblasts, or saline, were injected into the scar tissue seven days after infarction. One month later, immunostaining identified rhEPO expression in the implanted engineered cells but not in controls. Compared with non-transduced fibroblasts or saline injection, implanted rhEPO-producing fibroblasts promoted vascularization in the scar, and prevented cell apoptosis. By two-dimensional echocardiography and postmortem morphometry, transplanted EPO-engineered fibroblasts did not prevent left ventricular (LV) dysfunction and adverse LV remodeling 5 and 9 weeks after MI. Conclusion In situ expression of rhEPO enhances vascularization and reduces cell apoptosis in the infarcted myocardium. However, local EPO therapy is insufficient for functional improvement after MI in rat. PMID:19014419

  19. Erythropoietin assay: present status of methods, pitfalls, and results in polycythemic disorders.

    PubMed

    Popovic, W J; Adamson, J W

    1978-01-01

    Mammalian erythropoiesis is regulated primarily by the hormone erythropoietin (ESP). Studies of ESF have provided information about its biochemistry and its role in regulating hemoglobin synthesis. Such studies rely on assays for erythropoietic activity in biological fluid. The assay which has proven most valuable and is used most widely is based upon the incorporation of radioactive iron into newly-formed red cells of polycythemic mice. While this assay has gained wide acceptance, it is expensive, cumbersome, imprecise, and insensitive, capable of reliably detecting no less than 50 milliunits of erythropoietin. Improvements in assay techniques will require new methodology relying primarily on immunologic recognition for the determination of hormone activity. Currently under development and in experimental use are radioimmunoassays and a hemagglutination inhibition assay. While work has progressed in these areas, these assays are not of proven value at present and meaningful physiological correlations have not emerged from their use. Alternatively, assays for hormone activity using suspensions of hematopoietic cells and the measurement of incorporation of radioactive isotopes into hemoglobin have provided both improvement in sensitivity and precision. The disadvantage of these types of assays is that they are sensitive to factors other than ESF and may give misleading information, depending on whether the factors present stimulate or inhibit cellular proliferation and hemoglobin synthesis. While such techniques may provide a temporary solution to some problems associated with assaying ESF for purification or physiological studies, they are not the best answer to the overall problem of hormone detection and characterization. The most important contribution to this field will be the availability of large amounts of highly purified and well-characterized ESF.

  20. Erythropoietin reduces ischemia-reperfusion injury after liver transplantation in rats.

    PubMed

    Schmeding, Maximilian; Hunold, Gerhard; Ariyakhagorn, Veravoorn; Rademacher, Sebastian; Boas-Knoop, Sabine; Lippert, Steffen; Neuhaus, Peter; Neumann, Ulf P

    2009-07-01

    Human recombinant Erythropoietin (rHuEpo) has recently been shown to be a potent protector of ischemia- reperfusion injury in warm-liver ischemia. Significant enhancement of hepatic regeneration and survival after large volume partial hepatic resection has also been demonstrated. It was the aim of this study to evaluate the capacities of rHuEpo in the setting of rat liver transplantation. One-hundred-and-twenty Wistar rats were used: 60 recipients received liver transplantation following donor organ treatment (60 donors) with either 1000 IU rHuEpo or saline injection (controls) into portal veins (cold ischemia 18 h, University of Wisconsin (UW) solution). Recipients were allocated to two groups, which either received 1000 IU rHuEpo at reperfusion or an equal amount of saline (control). Animals were sacrificed at defined time-points (2, 4.5, 24, 48 h and 7 days postoperatively) for analysis of liver enzymes, histology [hematoxylin-eosin (HE) staining, periodic acid Schiff staining (PAS)], immunostaining [terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), Hypoxyprobe] and real-time polymerase chain reaction (RT-PCR) of cytokine mRNA (IL-1, IL-6). Lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) values were significantly reduced among the epo-treated animals 24 and 48 h after liver transplantation (LT). The TUNEL and Hypoxyprobe analyses as well as necrotic index evaluation displayed significant reduction of apoptosis and necrosis in rHuEpo-treated graft livers. Erythropoietin reduces ischemia-reperfusion injury after orthotopic liver transplantation in rats.

  1. The pharmacokinetics and pharmacodynamics of recombinant human erythropoietin in haemodialysis patients.

    PubMed Central

    Brockmöller, J; Köchling, J; Weber, W; Looby, M; Roots, I; Neumayer, H H

    1992-01-01

    1. The pharmacokinetics of and therapeutic response to recombinant human erythropoietin (rcEPO) were studied in 12 patients under chronic haemodialysis on a thrice weekly intravenous rcEPO treatment scheme. The kinetics of rcEPO were also assessed after a subcutaneous injection during the initial period and during maintenance treatment. RcEPO was measured in plasma by radioimmunoassay. 2. After the first i.v. dose plasma erythropoietin concentrations were best described by a monoexponential disposition function with a mean (+/- s.d.) elimination half-life of 5.4 +/- 1.7 h. The volume of distribution was 70 +/- 5.2 ml kg-1 and the clearance was 10.1 +/- 3.5 ml h-1 kg-1 (n = 12). 3. After 3 months of continuous therapy, the plasma half-life of rcEPO decreased by 15% (P < 0.05, mean half-life during steady state: 4.6 +/- 2.8 h), while mean clearance and volume of distribution remained constant. 4. After the first s.c. injection the mean (+/- s.d.) absorption time was 22 +/- 11 h and systemic availability was 44 +/- 7%. 5. Changes in haemoglobin concentrations were described by a linear additive dose-response model, defined by an efficacy constant (Keff) and the mean erythrocyte lifetime (MRTHb). The sample mean (+/- s.d.) Keff was 0.043 +/- 0.017 g dl-1 Hb per 1000 units rcEPO and MRTHb was 10.02 +/- 1.75 weeks. The net effect of rcEPO treatment was described by the area under the unit-dose-response curve (AUEC) with a mean (+/- s.d.) value of 0.45 +/- 0.23 g dl-1 weeks. 6. RcEPO clearance showed a significant positive correlation (r2 = 0.41) with the effectiveness of rcEPO therapy, as measured by the parameters Keff or AUEC. PMID:1493082

  2. Recovery of radiation-induced dry eye and corneal damage by pretreatment with adenoviral vector-mediated transfer of erythropoietin to the salivary glands in mice.

    PubMed

    Rocha, Eduardo M; Cotrim, Ana P; Zheng, Changyu; Riveros, Paola Perez; Baum, Bruce J; Chiorini, John A

    2013-04-01

    Therapeutic doses of radiation (RTx) causes dry eye syndrome (DES), dry mouth, and as in other sicca syndromes, they are incurable. The aims of this work are as follows: (a) to evaluate a mouse model of DES induced by clinically relevant doses of radiation, and (b) to evaluate the protective effect of erythropoietin (Epo) in preventing DES. C3H female mice were subjected to five sessions of RTx, with or without pre-RTx retroductal administration of the AdLTR2EF1a-hEPO (AdEpo) vector in the salivary glands (SG), and compared with naïve controls at Day 10 (10d) (8 Gy fractions) and 56 days (56d) (6 Gy fractions) after RTx treatment. Mice were tested for changes in lacrimal glands (LG), tear secretion (phenol red thread), weight, hematocrit (Hct), and markers of inflammation, as well as microvessels and oxidative damage. Tear secretion was reduced in both RTx groups, compared to controls, by 10d. This was also seen at 56d in RTx but not AdEpo+RTx group. Hct was significantly higher in all AdEpo+RTx mice at 10d and 56d. Corneal epithelium was significantly thinner at 10d in the RTx group compared with AdEpo+RTx or the control mice. There was a significant reduction at 10d in vascular endothelial growth factor (VEGF)-R2 in LG in the RTx group that was prevented in the AdEpo+RTx group. In conclusion, RTx is able to induce DES in mice. AdEpo administration protected corneal epithelia and resulted in some recovery of LG function, supporting the value of further studies using gene therapy for extraglandular diseases.

  3. Toward Homogeneous Erythropoietin: Application of Metal Free Dethiylation in the Chemical Synthesis of the Ala79-Arg166 Glycopeptide Domain

    PubMed Central

    Dong, Suwei; Shang, Shiying; Tan, Zhongping

    2013-01-01

    We describe herein the assembly of hEPO(79–166), a key glycopeptide segment en route to erythropoietin, in minimally protected form. Key to the success of this synthetic endeavor was the application of our two-step cysteine-free native chemical ligation strategy, by which we achieved formal ligation at alanine and proline residues through the use of an N-terminal amino acid surrogate presenting a readily removable thiol functionality. PMID:23585694

  4. Pure red cell aplasia associated with recombinant erythropoietin: a case report and brief review of the literature.

    PubMed

    Mohd Slim, M Atif; Shaik, Riaz

    2013-11-22

    Pure red cell aplasia (PRCA) is a rare adverse effect of recombinant erythropoietin (rEPO). Affected patients rapidly become transfusion-dependent, with many requiring immunosuppressive therapy for remission. We report a confirmed case in an elderly female, possibly the first of its kind in New Zealand, who was started on rEPO for anaemia of chronic kidney disease. We also briefly review current literature on rEPO-associated PRCA.

  5. Treatment of optic neuritis with erythropoietin (TONE): a randomised, double-blind, placebo-controlled trial—study protocol

    PubMed Central

    Diem, Ricarda; Molnar, Fanni; Beisse, Flemming; Gross, Nikolai; Drüschler, Katharina; Heinrich, Sven P; Joachimsen, Lutz; Rauer, Sebastian; Pielen, Amelie; Sühs, Kurt-Wolfram; Linker, Ralf Andreas; Huchzermeyer, Cord; Albrecht, Philipp; Hassenstein, Andrea; Aktas, Orhan; Guthoff, Tanja; Tonagel, Felix; Kernstock, Christoph; Hartmann, Kathrin; Kümpfel, Tania; Hein, Katharina; van Oterendorp, Christian; Grotejohann, Birgit; Ihorst, Gabriele; Maurer, Julia; Müller, Matthias; Volkmann, Martin; Wildemann, Brigitte; Platten, Michael; Wick, Wolfgang; Heesen, Christoph; Schiefer, Ulrich; Wolf, Sebastian; Lagrèze, Wolf A

    2016-01-01

    Introduction Optic neuritis leads to degeneration of retinal ganglion cells whose axons form the optic nerve. The standard treatment is a methylprednisolone pulse therapy. This treatment slightly shortens the time of recovery but does not prevent neurodegeneration and persistent visual impairment. In a phase II trial performed in preparation of this study, we have shown that erythropoietin protects global retinal nerve fibre layer thickness (RNFLT-G) in acute optic neuritis; however, the preparatory trial was not powered to show effects on visual function. Methods and analysis Treatment of Optic Neuritis with Erythropoietin (TONE) is a national, randomised, double-blind, placebo-controlled, multicentre trial with two parallel arms. The primary objective is to determine the efficacy of erythropoietin compared to placebo given add-on to methylprednisolone as assessed by measurements of RNFLT-G and low-contrast visual acuity in the affected eye 6 months after randomisation. Inclusion criteria are a first episode of optic neuritis with decreased visual acuity to ≤0.5 (decimal system) and an onset of symptoms within 10 days prior to inclusion. The most important exclusion criteria are history of optic neuritis or multiple sclerosis or any ocular disease (affected or non-affected eye), significant hyperopia, myopia or astigmatism, elevated blood pressure, thrombotic events or malignancy. After randomisation, patients either receive 33 000 international units human recombinant erythropoietin intravenously for 3 consecutive days or placebo (0.9% saline) administered intravenously. With an estimated power of 80%, the calculated sample size is 100 patients. The trial started in September 2014 with a planned recruitment period of 30 months. Ethics and dissemination TONE has been approved by the Central Ethics Commission in Freiburg (194/14) and the German Federal Institute for Drugs and Medical Devices (61-3910-4039831). It complies with the Declaration of Helsinki

  6. Erythropoietin test

    MedlinePlus

    ... polycythemia (high red blood cell count) or other bone marrow disorders. A change in red blood cells will affect the release of EPO. For example, persons with anemia have too few red blood cells, so more EPO is produced.

  7. Evaluation of the osteogenesis and angiogenesis effects of erythropoietin and the efficacy of deproteinized bovine bone/recombinant human erythropoietin scaffold on bone defect repair.

    PubMed

    Li, Donghai; Deng, Liqing; Xie, Xiaowei; Yang, Zhouyuan; Kang, Pengde

    2016-06-01

    Erythropoietin (EPO) could promote the angiogenesis and may also play a role in bone regeneration. This study was conducted to evaluate the osteogenesis and angiogenesis effects of EPO and the efficacy of deproteinized bovine bone/recombinant human EPO scaffold on bone defect repair. Twenty-four healthy adult goats were chosen to build goat defects model and randomly divided into four groups. The goats were treated with DBB/rhEPO scaffolds (group A), porous DBB scaffolds (group B), autogenous cancellous bone graft (group C), and nothing (group D). Animals were evaluated with radiological and histological methods at 4, 8 and 12 weeks after surgery. The grey value of radiographs was used to evaluate the healing of the defects and the outcome revealed that the group A had a better outcome of defect healing compared with group B (P < 0.05). However, the grey values in group A were lower than group C at week 4 and week 8 (P < 0.05), but at week 12 their difference had no statistical significance (P > 0.05). The newly formed bone area was calculated from histological sections and the results demonstrated that the amount of new bone in group A increased significantly compared with that in group B (P < 0.05) but was inferior to that in group C (P > 0.05) at 4, 8, 12 weeks respectively. In addition, the expression of vascular endothelial growth factor (VEGF) by immunohistochemical testing and real-time polymerase chain reaction at 12 weeks in group A was significantly higher than that in group B (P < 0.05), and also better than that in group C at week 4 and week 8 (P < 0.05), but at week 12 their difference had no statistical significance (P > 0.05). Therefore, EPO has significant effects on bone formation and angiogenesis, and has capacity to promote the repair of bone defects. It is worthy of being recommended to further studies.

  8. Response to erythropoietin in erythroid subclones of the factor-dependent cell line 32D is determined by translocation of the erythropoietin receptor to the cell surface.

    PubMed Central

    Migliaccio, A R; Migliaccio, G; D'Andrea, A; Baiocchi, M; Crotta, S; Nicolis, S; Ottolenghi, S; Adamson, J W

    1991-01-01

    Regulation of the expression of the erythropoietin (Epo) receptor (EpoR) gene is under the control of transcriptional regulatory factor GATA-1. GATA-1 is expressed widely among the nonerythroid, factor-dependent subclones of the interleukin 3-dependent mouse cell line 32D. Consequently, to determine whether GATA-1 and EpoR gene expression are linked even in nonerythroid cells, we have studied the correlation of GATA-1 expression with expression and function of EpoR in these cell lines. EpoR mRNA (by RNase protection analysis) and EpoR protein (by specific antibody immunoprecipitation of metabolically labeled EpoR protein) were detectable not only in 32D and 32D Epo (an Epo-dependent subclone) but also in 32D GM, a subclone dependent for growth on granulocyte/macrophage colony-stimulating factor. EpoR mRNA also was detectable by PCR in 32D G, a subclone dependent for growth on granulocyte colony-stimulating factor. However, only 32D Epo cells bound 125I-labeled Epo and expressed EpoR protein on the cell surface, as determined by immunoprecipitation of surface-labeled proteins. These results indicate that, in these factor-dependent cell lines, the major regulatory step determining the erythroid-specific response to Epo is the efficiency of EpoR protein translocation to the cell surface. Mechanisms that could affect lineage-specific translocation are the presence of a chaperone protein, erythroid-specific editing of EpoR mRNA, or altered processing of the EpoR protein to the cell surface. In this model, lineage-restricted responses to growth factors such as Epo are determined not by expression of the genes for growth factor receptors but, rather, by appropriate processing of the receptor protein. Images PMID:1722318

  9. Cardioprotection of exogenous erythropoietin in mice with ligature-induced aortic stenosis: effects on maladaptive cardiac hypertrophy.

    PubMed

    Zheng, L; Xu, J; Qiu, W; Liu, X; Zhao, C-M; Chen, D; Chen, Y

    2010-02-01

    Pre-operative treatment with recombinant human erythropoietin may improve aortic stenosis patients' condition, including anemia and/or cardiac dysfunction, for subjecting to aortic valve replacement. In this study, we tested this hypothesis in a mouse model of aortic stenosis. Adult male mice were subjected to either aortic stenosis created by aortic ligature or sham operation. Aortic stenosis for 4 weeks caused cardiac hypertrophy, pulmonary congestion and left ventricular dysfunction. It was associated with increased levels of tumor necrosis factor-alpha in serum and myocardium, and reduced levels of interleukin-10 in myocardium but not in serum. Myocyte apoptosis rate, level of cleaved caspase 3, activity of nuclear factor-kappaB and expression of p38-MAPK pathway were also elevated. Erythropoietin treatment increased hematocrit but did not prevent the development of cardiac hypertrophy. It, however, reduced the apoptosis, prevented the increases in tumor necrosis factor-alpha, nuclear factor-kappaB activation and phosphorylation of p38, and attenuated the increases in lung weight, the decreases in LVEF and LVFS, and the increases in LVDd and LVDs. In conclusion recombinant human erythropoietin has cardioprotective effects in maladaptive cardiac hypertrophy by inhibiting nuclear factor-kappaB activation, phosphorylation of p38-MAPK pathway, and production of tumor necrosis factor-alpha, together leading to a reduced apoptosis.

  10. Long-term treatment of anemia with recombinant human erythropoietin in familial amyloidosis TTR V30M.

    PubMed

    Beirão, Idalina; Lobato, Luísa; Moreira, Luciana; Mp Costa, Paulo; Fonseca, Isabel; Cabrita, António; Porto, Graça

    2008-09-01

    Familial amyloidosis or familial amyloid polyneuropathy (FAP) TTR V30M is a hereditary disease presented, in most cases, as a sensorimotor and autonomic neuropathy. Normocytic and normochromic anaemia was found in 24.8% of symptomatic FAP patients associated to lower serum erythropoietin (Epo) levels. Erythropoietin has been reported as efficient in anaemia correction in this disease. To evaluate the tolerance and efficacy of this treatment, a retrospective longitudinal study with 24 patients was undertaken. Patients were followed for at least 6 months. Haemoglobin, hematocrit, iron status, serum creatinine and urea and r-HuEPO doses were monitored, at 0, 3 months, 6 months and at the end of the follow-up. Long-term use of r-HuEPO proved to be efficient in the treatment of anaemia in familial amyloidosis TTR V30M and, despite the disease progression, no resistance cases to this treatment were observed. Positive side effects, like improvement on orthostatic hypotension symptoms and well-being sensation, contributing to confirm erythropoietin as a drug of choice to treat anaemia in amyloidosis TTR V30M.

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

    PubMed

    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.

  12. SDS-PAGE of recombinant and endogenous erythropoietins: benefits and limitations of the method for application in doping control.

    PubMed

    Reichel, Christian; Kulovics, Ronald; Jordan, Veronika; Watzinger, Martina; Geisendorfer, Thomas

    2009-01-01

    Doping of athletes with recombinant and genetically modified erythropoietins (EPO) is currently detected by isoelectric focusing (IEF). The application of these drugs leads to a significant change in the isoform profile of endogenous urinary erythropoietin (uhEPO). Dynepo, MIRCERA, biosimilars with variable IEF-profiles as well as active urines and effort urines have made additional testing strategies necessary. The new generation of small molecule EPO-receptor stimulating agents like Hematide will also challenge the analytical concept of detecting the abuse of erythropoiesis stimulating agents (ESA). By determining their apparent molecular masses with SDS-PAGE a clear differentiation between endogenous and exogenous substances also concerning new EPO modifications is possible. Due to the orthogonal character of IEF- and SDS-PAGE both methods complement each other. The additional benefits of SDS-PAGE especially in relation to active and effort urines as well as the detection of Dynepo were investigated. Due to significant differences between the apparent molecular masses of uhEPO/serum EPO (shEPO) and recombinant, genetically or chemically modified erythropoietins the presence of active or effort urines was easily revealed. The characteristic band shape and apparent molecular mass of Dynepo on SDS-PAGE additionally evidenced the presence of this substance in urine. A protocol for the detection of EPO-doping in serum and plasma by SDS-PAGE was developed. Blood appears to be the ideal matrix for detecting all forms ESA-doping in the future.

  13. Optimization and qualification of capillary zone electrophoresis method for glycoprotein isoform distribution of erythropoietin for quality control laboratory.

    PubMed

    Zhang, Junge; Chakraborty, Utpal; Villalobos, Annabelle P; Brown, John M; Foley, Joe P

    2009-10-15

    The European Pharmacopoeia (Ph. Eur.) monograph for Erythropoietin Concentrated Solution describes a capillary zone electrophoresis method for identification of recombinant human erythropoietin. However, this method has shown poor reproducibility due to inadequate capillary conditioning. We have modified the Ph. Eur. method to make it more robust and suitable for the quality control laboratory for the analysis of epoetin alfa and epoetin alfa after formulation with polysorbate 80. This study qualified the modified method by showing improved robustness and reproducibility. The study also characterized and qualified a secondary standard of epoetin alfa as a substitute for the primary standard, Ph. Eur. erythropoietin Biological Reference Preparation, which is available in limited supply. Four sets of analyses were performed to assess repeatability, intermediate precision, and the secondary standard. The results showed that the modified method is suitable for its intended purpose to test epoetin alfa and formulated epoetin alfa samples. The epoetin alfa secondary standard is a suitable substitute for the primary standard. Further, we developed a procedure for the removal of polysorbate 80 from formulated epoetin alfa, allowing the material to be analyzed by the modified Ph. Eur. method.

  14. Effect of acute and chronic cobalt administration on carotid body chemoreceptors responses.

    PubMed

    Morelli, L; Di Giulio, C; Iezzi, M; Data, P G

    1994-06-30

    Chronic cobalt exposure leads to release and production of erythropoietin and consequently to polycythemia. Accordingly, cellular elements sensitive to oxygen in the carotid body, would manifest responses during acute and chronic cobalt administration. The carotid body, detects gas changes (PO2, PCO2/pH) in the arterial blood and regulates ventilation and circulation by the afferent nerve discharge. We hypothesized that cobalt interacts with an oxygen sensitive mechanism in the carotid chemoreception and in erythropoietin producing cells. Twelve cats were anesthetized, paralysed and artificially ventilated; few fiber preparation of carotid sinus nerve were recorded during close intraarterial injection of cobalt. In another protocol, 12 rats received an intraperitoneal dose of CoCl2 (10 mg/kg) daily for 6 weeks. At the end, the carotid body was fixed in situ by superfusion. Ultrastructural and morphometric studies were made. Acute administration (0.08-2.3 mumol) promptly stimulated the chemoreceptor afferents. Type I cells increased significantly along with erythropoiesis in the chronic cobalt treated rats. The stimulatory effects of cobalt on the carotid body chemoreceptor showed that sensitive mechanisms in the kidney and in the carotid body are similar, and cobalt interacts with the physiological responses of oxygen.

  15. Hypoxic pulmonary vasoconstriction, carotid body function and erythropoietin production in adult rats perinatally exposed to hyperoxia

    PubMed Central

    Prieto-Lloret, Jesus; Ramirez, Maria; Olea, Elena; Moral-Sanz, Javier; Cogolludo, Angel; Castañeda, Javier; Yubero, Sara; Agapito, Teresa; Gomez-Niño, Angela; Rocher, Asuncion; Rigual, Ricardo; Obeso, Ana; Perez-Vizcaino, Francisco; González, Constancio

    2015-01-01

    Adult mammalians possess three cell systems that are activated by acute bodily hypoxia: pulmonary artery smooth muscle cells (PASMC), carotid body chemoreceptor cells (CBCC) and erythropoietin (EPO)-producing cells. In rats, chronic perinatal hyperoxia causes permanent carotid body (CB) atrophy and functional alterations of surviving CBCC. There are no studies on PASMC or EPO-producing cells. Our aim is to define possible long-lasting functional changes in PASMC or EPO-producing cells (measured as EPO plasma levels) and, further, to analyse CBCC functional alterations. We used 3- to 4-month-old rats born and reared in a normal atmosphere or exposed to perinatal hyperoxia (55–60% O2 for the last 5–6 days of pregnancy and 4 weeks after birth). Perinatal hyperoxia causes an almost complete loss of hypoxic pulmonary vasoconstriction (HPV), which was correlated with lung oxidative status in early postnatal life and prevented by antioxidant supplementation in the diet. O2-sensitivity of K+ currents in the PASMC of hyperoxic animals is normal, indicating that their inhibition is not sufficient to trigger HPV. Perinatal hyperoxia also abrogated responses elicited by hypoxia on catecholamine and cAMP metabolism in the CB. An increase in EPO plasma levels elicited by hypoxia was identical in hyperoxic and control animals, implying a normal functioning of EPO-producing cells. The loss of HPV observed in adult rats and caused by perinatal hyperoxia, comparable to oxygen therapy in premature infants, might represent a previously unrecognized complication of such a medical intervention capable of aggravating medical conditions such as regional pneumonias, atelectases or general anaesthesia in adult life. Key points Adult animals that have been perinatally exposed to oxygen-rich atmospheres (hyperoxia), recalling those used for oxygen therapy in infants, exhibit a loss of hypoxic pulmonary vasoconstriction, whereas vasoconstriction elicited by depolarizing agents is

  16. Analysis of the erythropoietin receptor gene in patients with myeloproliferative and myelodysplastic syndromes.

    PubMed

    Mittelman, M; Gardyn, J; Carmel, M; Malovani, H; Barak, Y; Nir, U

    1996-06-01

    The human erythropoietin receptor (EpoR) gene has been cloned and characterized. Very few EpoR genetic abnormalities have been reported so far. Polycythemia vera (PV) is characterized by low/normal serum erythropoietin (Epo) levels with proposed Epo hypersensitivity. Myelodysplastic syndromes (MDS) are characterized by refractory anemia with variable serum Epo levels. Several reports have suggested EpoR abnormalities in both types of stem cell disorders. We analyzed DNA obtained from peripheral blood mononuclear cells of seven healthy controls, 20 patients with myeloproliferative disorders (MPD, 11 patients with PV, five agnogenic myeloid metaplasia with myelofibrosis, four essential thrombocytosis) and eight patients with refractory anemia with ringed sideroblasts (RARS), an MDS variant. The DNA was digested with four restriction enzymes (BamHI, Bgl II, Sacl and HindIII), followed by Southern blot, using a 32P radiolabeled probe, containing 1.5 kb of the human EpoR cDNA. All 20 MPD patients and seven out of the eight MDS patients demonstrated a restriction pattern which was identical to the seven normal controls, as well as to the erythroid cell line K562, and also consistent with the expected restriction map, for all four enzymes tested. One RARS patient had a normal pattern with three enzymes but a different one with HindIII. The HindIII 12 kb large band was replaced by a faint 12 kb band and a new (about 9 kb) band appeared. The EpoR restriction map and the normal pattern obtained with the other three enzymes suggest that this patient has a 3 kb upstream deletion in one allelic EpoR gene. The same molecular pattern was detected in the patient's sister, who suffers from anemia with mild bone marrow (BM) dyserythropoiesis and plasmacytosis. Northern blot analysis showed that the patient's BM RNA carried normal EpoR message. This familial pattern may represent polymorphism. However, the patient's very high serum Epo level, her resistance to treatment with

  17. 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

    SciTech Connect

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

    2011-06-01

    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 < 0.048), surgery (p < 0.042), no smoking during radiotherapy (p = 0.024), and no EPO expression (p = 0.001). A trend was observed for a KPS of >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

  18. A "classical" homodimeric erythropoietin receptor is essential for the antiapoptotic effects of erythropoietin on differentiated neuroblastoma SH-SY5Y and pheochromocytoma PC-12 cells.

    PubMed

    Um, Moonkyoung; Gross, Alec W; Lodish, Harvey F

    2007-03-01

    The hematopoietic cytokine erythropoietin (Epo) exerts cytoprotective effects on several types of neuronal cells both in vivo and in culture. Detailed molecular mechanisms underlying this phenomenon have not been elucidated and even the identity of the cytoprotective Epo receptors in neuronal cells is controversial. Here we show that Epo prevents staurosporine-induced apoptosis of differentiated human neuroblastoma SH-SY5Y cells, and activates the STAT5, AKT and MAPK signaling pathways. Differentiated SH-SY5Y cells have fewer than 50 high affinity Epo surface binding sites per cell, which could not be detected by standard assays measuring binding of 125I-labeled Epo. However, by measuring endocytosis of 125I-Epo, we could reliably quantify very small numbers of high-affinity Epo surface binding sites. Using SH-SY5Y cells stably expressing an Epo receptor (EpoR) shRNA and thus lacking detectable EpoR expression, we show that high affinity binding of Epo to these neuronal cells is mediated by the hematopoietic EpoR, and that this EpoR is also essential for the antiapoptotic activity of Epo. In contrast, a mutant Epo that has an intact binding site 1 but a non-functional binding site 2 and hence binds only to one cell surface EpoR molecule ("site 2" Epo mutant) displays significantly lower antiapoptotic activity than wild-type Epo. Furthermore, expression of the GM-CSF/IL-3/IL-5 receptor common beta chain, which was proposed to be responsible for the cytoprotective activity of Epo on certain types of neuronal cells, was undetectable in differentiated SH-SY5Y cells. Epo also alleviated staurosporine-induced apoptosis of rat PC-12 pheochromocytoma cells while the R103A "site 2" Epo mutant did not, and we could not detect expression of the common beta chain in PC-12 cells. Together our results indicate that Epo exerts its antiapoptotic effects on differentiated SH-SY5Y and PC-12 cells through the standard stoichiometry of one molecule of Epo binding to two EpoR subunits

  19. Restoration of Haemoglobin Level Using Hydrodynamic Gene Therapy with Erythropoietin Does Not Alleviate the Disease Progression in an Anaemic Mouse Model for TGFβ1-Induced Chronic Kidney Disease.

    PubMed

    Pedersen, Lea; Wogensen, Lise; Marcussen, Niels; Cecchi, Claudia R; Dalsgaard, Trine; Dagnæs-Hansen, Frederik

    2015-01-01

    Erythropoietin, Epo, is a 30.4 kDa glycoprotein hormone produced primarily by the fetal liver and the adult kidney. Epo exerts its haematopoietic effects by stimulating the proliferation and differentiation of erythrocytes with subsequent improved tissue oxygenation. Epo receptors are furthermore expressed in non-haematopoietic tissue and today, Epo is recognised as a cytokine with many pleiotropic effects. We hypothesize that hydrodynamic gene therapy with Epo can restore haemoglobin levels in anaemic transgenic mice and that this will attenuate the extracellular matrix accumulation in the kidneys. The experiment is conducted by hydrodynamic gene transfer of a plasmid encoding murine Epo in a transgenic mouse model that overexpresses TGF-β1 locally in the kidneys. This model develops anaemia due to chronic kidney disease characterised by thickening of the glomerular basement membrane, deposition of mesangial matrix and mild interstitial fibrosis. A group of age matched wildtype littermates are treated accordingly. After a single hydrodynamic administration of plasmid DNA containing murine EPO gene, sustained high haemoglobin levels are observed in both transgenic and wildtype mice from 7.5 ± 0.6 mmol/L to 9.4 ± 1.2 mmol/L and 10.7 ± 0.3 mmol/L to 15.5 ± 0.5 mmol/L, respectively. We did not observe any effects in the thickness of glomerular or tubular basement membrane, on the expression of different collagen types in the kidneys or in kidney function after prolonged treatment with Epo. Thus, Epo treatment in this model of chronic kidney disease normalises haemoglobin levels but has no effect on kidney fibrosis or function.

  20. Targeted delivery of erythropoietin by transcranial focused ultrasound for neuroprotection against ischemia/reperfusion-induced neuronal injury: a long-term and short-term study.

    PubMed

    Wu, Sheng-Kai; Yang, Ming-Tao; Kang, Kai-Hsiang; Liou, Houng-Chi; Lu, Dai-Hua; Fu, Wen-Mei; Lin, Win-Li

    2014-01-01

    Erythropoietin (EPO) is a neuroprotective agent against cerebral ischemia/reperfusion (I/R)-induced brain injury. However, its crossing of blood-brain barrier is limited. Focused ultrasound (FUS) sonication with microbubbles (MBs) can effectively open blood-brain barrier to boost the vascular permeability. In this study, we investigated the effects of MBs/FUS on extending the therapeutic time window of EPO and its neuroprotective effects in both acute and chronic phases. Male Wistar rats were firstly subjected to two common carotid arteries and right middle cerebral artery occlusion (three vessels occlusion, 3VO) for 50 min, and then the rats were treated with hEPO (human recombinant EPO, 5000 IU/kg) with or without MBs/FUS at 5 h after occlusion/reperfusion. Acute phase investigation (I/R, I/R+MBs/FUS, I/R+hEPO, and I/R+hEPO+MBs/FUS) was performed 24 h after I/R; chronic tests including cylinder test and gait analysis were performed one month after I/R. The experimental results showed that MBs/FUS significantly increased the cerebral content of EPO by bettering vascular permeability. In acute phase, both significant improvement of neurological score and reduction of infarct volume were found in the I/R+hEPO+MBs/FUS group, as compared with I/R and I/R+hEPO groups. In chronic phase, long-term behavioral recovery and neuronal loss in brain cortex after I/R injury was significantly improved in the I/R+hEPO+MBs/FUS group. This study indicates that hEPO administration with MBs/FUS sonication even at 5 h after occlusion/reperfusion can produce a significant neuroprotection.

  1. Erythropoietin attenuates renal and pulmonary injury in polymicrobial induced-sepsis through EPO-R, VEGF and VEGF-R2 modulation.

    PubMed

    Heitrich, Mauro; García, Daiana Maria de Los Ángeles; Stoyanoff, Tania Romina; Rodríguez, Juan Pablo; Todaro, Juan Santiago; Aguirre, María Victoria

    2016-08-01

    Sepsis remains the most important cause of acute kidney injury (AKI) and acute lung injury (ALI) in critically ill patients. The cecal ligation and puncture (CLP) model in experimental mice reproduces most of the clinical features of sepsis. Erythropoietin (EPO) is a well-known cytoprotective multifunctional hormone, which exerts anti-inflammatory, anti-oxidant, anti-apoptotic and pro-angiogenic effects in several tissues. The aim of this study was to evaluate the underlying mechanisms of EPO protection through the expression of the EPO/EPO receptor (EPO-R) and VEGF/VEF-R2 systems in kidneys and lungs of mice undergoing CLP-induced sepsis. Male inbred Balb/c mice were divided in three experimental groups: Sham, CLP, and CLP+EPO (3000IU/kg sc). Assessment of renal functional parameters, survival, histological examination, immunohistochemistry and/or Western blottings of EPO-R, VEGF and VEGF-R2 were performed at 18h post-surgery. Mice demonstrated AKI by elevation of serum creatinine and renal histologic damage. EPO treatment attenuates renal dysfunction and ameliorates kidney histopathologic changes. Additionally, EPO administration attenuates deleterious septic damage in renal cortex through the overexpression of EPO-R in tubular interstitial cells and the overexpression of the pair VEGF/VEGF-R2. Similarly CLP- induced ALI, as evidenced by parenchymal lung histopathologic alterations, was ameliorated through pulmonary EPO-R, VEGF and VEGF-R2 over expression suggesting and improvement in endothelial survival and functionality. This study demonstrates that EPO exerts protective effects in kidneys and lungs in mice with CLP-induced sepsis through the expression of EPO-R and the regulation of the VEGF/VEGF-R2 pair.

  2. HIF‑1 signaling pathway involving iNOS, COX‑2 and caspase‑9 mediates the neuroprotection provided by erythropoietin in the retina of chronic ocular hypertension rats.

    PubMed

    Gui, Dongmei; Li, Yanfeng; Chen, Xiaolong; Gao, Dianwen; Yang, Yang; Li, Xun

    2015-02-01

    This study aimed to investigate the impacts of erythropoietin (EPO) on the electroretinogram b‑wave (ERG‑b), and on the mRNA and protein expression levels of hypoxia‑inducible factor‑1α (HIF‑1α), inducible nitric oxide synthase (iNOS), cyclooxygenase‑2 (COX‑2) and caspase‑9 in chronic ocular hypertension rats. Episcleral vein cauterization (EVC) was used to establish the chronic ocular hypertension rat model based on the intraocular pressure (IOP) value. ERG‑b and mRNA and protein expression levels of HIF‑1α, iNOS, COX‑2 and caspase‑9 in normal, EVC‑treated and EVC combined with EPO (EVC+EPO)‑treated rats were measured by electroretinography, RT‑PCR and western blotting, respectively. Moreover, the correlations of HIF‑1α with IOP, ERG‑b, iNOS, COX‑2 and caspase‑9 were evaluated. The mRNA and protein expression levels of HIF‑1α, iNOS, COX‑2 and caspase‑9 in EVC‑treated rats were increased significantly compared with normal rats. The peak expression levels of HIF‑1α, iNOS, COX‑2 and caspase‑9 were respectively obtained 7, 7, 7 and 14 days postoperatively. Compared with EVC‑treated rats, EPO administration weakened the mRNA and protein expression levels of HIF‑1α, iNOS, COX‑2 and caspase‑9. The mRNA expression level of HIF‑1α demonstrated a significant positive correlation with IOP and ERG‑b. HIF‑1α was positively correlated with iNOS, COX‑2 and caspase‑9 at the mRNA and protein levels. The protective effect of EPO on the retina of chronic ocular hypertension rats may be mediated by the HIF‑1 signaling pathway involving iNOS, COX‑2 and caspase‑9.

  3. Erythropoietin and its Carbamylated Derivative Prevent the Development of Experimental Diabetic Autonomic Neuropathy in STZ-Induced Diabetic NOD-SCID Mice

    PubMed Central

    Schmidt, Robert E.; Green, Karen G.; Feng, Dongyan; Dorsey, Denise A.; Parvin, Curtis A.; Lee, Jin-Moo; Xiao, Qinlgi; Brines, Michael

    2008-01-01

    Autonomic neuropathy is a significant diabetic complication resulting in increased morbidity and mortality. Studies of autopsied diabetic patients and several rodent models demonstrate that the neuropathologic hallmark of diabetic sympathetic autonomic neuropathy in prevertebral ganglia is the occurrence of synaptic pathology resulting in distinctive dystrophic neurites (“neuritic dystrophy”). Our prior studies show that neuritic dystrophy is reversed by exogenous IGF-I administration without altering the metabolic severity of diabetes, i.e. functioning as a neurotrophic substance. The description of erythropoietin (EPO) synergy with IGF-I function and the recent discovery of EPO’s multifaceted neuroprotective role suggested it might substitute for IGF-I in treatment of diabetic autonomic neuropathy. Our current studies demonstrate EPO receptor (EPO-R) mRNA in a cDNA set prepared from NGF-maintained rat sympathetic neuron cultures which decreased with NGF deprivation, a result which demonstrates clearly that sympathetic neurons express EPO-R, a result confirmed by immunohistochemistry. Treatment of STZ-diabetic NOD-SCID mice have demonstrated a dramatic preventative effect of EPO and carbamylated EPO (CEPO, which is neuroprotective but not hematopoietic) on the development of neuritic dystrophy. Neither EPO nor CEPO had a demonstrable effect on the metabolic severity of diabetes. Our results coupled with reported salutary effects of EPO on postural hypotension in a few clinical studies of EPO-treated anemic diabetic and non-diabetic patients may reflect a primary neurotrophic effect of EPO on the sympathetic autonomic nervous system, rather than a primary hematopoietic effect. These findings may represent a major clinical advance since EPO has been widely and safely used in anemic patients due to a variety of clinical conditions. PMID:17967455

  4. Senior Administrators Should Have Administrative Contracts.

    ERIC Educational Resources Information Center

    Posner, Gary J.

    1987-01-01

    Recognizing that termination is viewed by the employee as the equivalent to capital punishment of a career, an administrative contract can reduce the emotional and financial entanglements that often result. Administrative contracts are described. (MLW)

  5. Circulating damage marker profiles support a neuroprotective effect of erythropoietin in ischemic stroke patients.

    PubMed

    Ehrenreich, Hannelore; Kästner, Anne; Weissenborn, Karin; Streeter, Jackson; Sperling, Swetlana; Wang, Kevin K; Worthmann, Hans; Hayes, Ronald L; von Ahsen, Nico; Kastrup, Andreas; Jeromin, Andreas; Herrmann, Manfred

    2011-01-01

    The German Multicenter EPO Stroke Trial, which investigated safety and efficacy of erythropoietin (EPO) treatment in ischemic stroke, was formally declared a negative study. Exploratory subgroup analysis, however, revealed that patients not receiving thrombolysis most likely benefited from EPO during clinical recovery, a result demonstrated in the findings of the Göttingen EPO Stroke Study. The present work investigated whether the positive signal on clinical outcome in this patient subgroup was mirrored by respective poststroke biomarker profiles. All patients of the German Multicenter EPO Stroke Trial nonqualifying for thrombolysis were included if they (a) were treated per protocol and (b) had at least two of the five follow-up blood samples for circulating damage markers drawn (n = 163). The glial markers S100B and glial fibrillary acid protein (GFAP) and the neuronal marker ubiquitin C-terminal hydrolase (UCH-L1) were measured by enzyme-linked immunosorbent assay in serum on d 1, 2, 3, 4 and 7 poststroke. All biomarkers increased poststroke. Overall, EPO-treated patients had significantly lower concentrations (area under the curve) over 7 d of observation, as reflected by the composite score of all three markers (Cronbach α = 0.811) and by UCH-L1. S100B and GFAP showed a similar tendency. To conclude, serum biomarker profiles, as an outcome measure of brain damage, corroborate an advantageous effect of EPO in ischemic stroke. In particular, reduction in the neuronal damage marker UCH-L1 may reflect neuroprotection by EPO.

  6. Dexamethasone mimics aspects of physiological acclimatization to 8 hours of hypoxia but suppresses plasma erythropoietin

    PubMed Central

    Liu, Chun; Croft, Quentin P. P.; Kalidhar, Swati; Brooks, Jerome T.; Herigstad, Mari; Smith, Thomas G.; Dorrington, Keith L.

    2013-01-01

    Dexamethasone ameliorates the severity of acute mountain sickness (AMS) but it is unknown whether it obtunds normal physiological responses to hypoxia. We studied whether dexamethasone enhanced or inhibited the ventilatory, cardiovascular, and pulmonary vascular responses to sustained (8 h) hypoxia. Eight healthy volunteers were studied, each on four separate occasions, permitting four different protocols. These were: dexamethasone (20 mg orally) beginning 2 h before a control period of 8 h of air breathing; dexamethasone with 8 h of isocapnic hypoxia (end-tidal Po2 = 50 Torr); placebo with 8 h of air breathing; and placebo with 8 h of isocapnic hypoxia. Before and after each protocol, the following were determined under both euoxic and hypoxic conditions: ventilation; pulmonary artery pressure (estimated using echocardiography to assess maximum tricuspid pressure difference); heart rate; and cardiac output. Plasma concentrations of erythropoietin (EPO) were also determined. Dexamethasone had no early (2-h) effect on any variable. Both dexamethasone and 8 h of hypoxia increased euoxic values of ventilation, pulmonary artery pressure, and heart rate, together with the ventilatory sensitivity to acute hypoxia. These effects were independent and additive. Eight hours of hypoxia, but not dexamethasone, increased the sensitivity of pulmonary artery pressure to acute hypoxia. Dexamethasone, but not 8 h of hypoxia, increased both cardiac output and systemic arterial pressure. Dexamethasone abolished the rise in EPO induced by 8 h of hypoxia. In summary, dexamethasone enhances ventilatory acclimatization to hypoxia. Thus, dexamethasone in AMS may improve oxygenation and thereby indirectly lower pulmonary artery pressure. PMID:23393065

  7. Erythropoietin augments bone formation in a rabbit posterolateral spinal fusion model.

    PubMed

    Rölfing, Jan Hendrik Duedal; Bendtsen, Michael; Jensen, Jonas; Stiehler, Maik; Foldager, Casper Bindzus; Hellfritzsch, Michel Bach; Bünger, Cody

    2012-07-01

    We tested the hypothesis that erythropoietin (EPO) enhances bone formation after posterolateral spinal fusion (PLF) in a rabbit model. Thirty-four adult rabbits underwent posterolateral intertransverse arthrodesis at the L5-L6 level using 2.0 g autograft per side. The animals were randomly divided into two groups receiving subcutaneous daily injections of either EPO or saline for 20 days. Treatment commenced 2 days preoperatively. Hemoglobin was monitored at baseline and 2, 4, and 6 weeks after fusion surgery. After euthanasia 6 weeks postoperatively, manual palpation, radiographic, and histomorphometric examinations were performed. Bone volume of the fusion mass was estimated by CT after 6 weeks. EPO increased bone fusion volume to 3.85 ccm (3.66-4.05) compared with 3.26 ccm (2.97-3.55) in the control group (p<0.01). EPO treatment improved vascularization of the fusion mass and increased hemoglobin levels (p<0.01). Fusion rate tended to be higher in the EPO group based on manual palpation, CT, and radiographic examinations. For the first time EPO has shown to augment bone formation after autograft PLF in a rabbit model. Increased vascularization provides a partial explanation for the efficacy of EPO as a bone autograft enhancer.

  8. Potential of mesenchymal stem cells by adenovirus-mediated erythropoietin gene therapy approaches for bone defect.

    PubMed

    Li, Chen; Ding, Jian; Jiang, Liming; Shi, Ce; Ni, Shilei; Jin, Han; Li, Daowei; Sun, Hongchen

    2014-11-01

    Regeneration of large bone defects is a common clinical problem. Recent studies have shown that mesenchymal stem cells (MSCs) have emerged as a promising alternative to traditional surgical techniques. However, it is still a key question how to enhance the osteogenic potential of MSCs for possible clinical trials. The aim of the present study was to investigate the effect of adenovirus-mediated erythropoietin (Ad-EPO) transfer on BMSCs, we performed extensive in vitro/in vivo assays in this study. Flow cytometry analysis and the result of MTT showed that EPO could promote BMSCs proliferation. QPCR data demonstrated that EPO increased expressions of Runx2, Sp7, and Col1 in osteoblast at various time points and also increased alkaline phosphatase activity and the calcium deposition. These results indicate that EPO can increase the differentiation of osteoblast. Importantly, in vivo assays clearly demonstrate that EPO can efficiently induce new bone formation in the bone defect model. Our results strongly suggest that EPO can affect osteoblast differentiation and play important roles in bone regeneration leading to an increase in bone formation.

  9. Schwann cells express erythropoietin receptor and represent a major target for Epo in peripheral nerve injury.

    PubMed

    Li, Xiaoqing; Gonias, Steven L; Campana, W Marie

    2005-09-01

    Erythropoietin (Epo) expresses potent neuroprotective activity in the peripheral nervous system; however, the underlying mechanism remains incompletely understood. In this study, we demonstrate that Epo is upregulated in sciatic nerve after chronic constriction injury (CCI) and crush injury in rats, largely due to local Schwann cell production. In uninjured and injured nerves, Schwann cells also express Epo receptor (EpoR), and its expression is increased during Wallerian degeneration. CCI increased the number of Schwann cells at the injury site and the number was further increased by exogenously administered recombinant human Epo (rhEpo). To explore the activity of Epo in Schwann cells, primary cultures were established. These cells expressed cell-surface Epo receptors, with masses of 71 and 62 kDa, as determined by surface protein biotinylation and affinity precipitation. The 71-kDa species was rapidly but transiently tyrosine-phosphorylated in response to rhEpo. ERK/MAP kinase was also activated in rhEpo-treated Schwann cells; this response was blocked by pharmacologic antagonism of JAK-2. RhEpo promoted Schwann cell proliferation, as determined by BrdU incorporation. Cell proliferation was ERK/MAP kinase-dependent. These results support a model in which Schwann cells are a major target for Epo in injured peripheral nerves, perhaps within the context of an autocrine signaling pathway. EpoR-induced cell signaling and Schwann cell proliferation may protect injured peripheral nerves and promote regeneration.

  10. Erythropoietin promotes bone formation through EphrinB2/EphB4 signaling.

    PubMed

    Li, C; Shi, C; Kim, J; Chen, Y; Ni, S; Jiang, L; Zheng, C; Li, D; Hou, J; Taichman, R S; Sun, H

    2015-03-01

    Recent studies have demonstrated that erythropoietin (EPO) has extensive nonhematopoietic biological functions. However, little is known about how EPO regulates bone formation, although several studies suggested that EPO can affect bone homeostasis. In this study, we investigated the effects of EPO on the communication between osteoclasts and osteoblasts through the ephrinB2/EphB4 signaling pathway. We found that EPO slightly promotes osteoblastic differentiation with the increased expression of EphB4 in ST2 cells. However, EPO increased the expression of Nfatc1 and ephrinB2 but decreased the expression of Mmp9 in RAW264.7 cells, resulting in an increase of ephrinB2-expressing osteoclasts and a decrease in resorption activity. The stimulation of ephrinB2/EphB4 signaling via ephrinB2-Fc significantly promoted EPO-mediated osteoblastic differentiation in ST2 cells. EphB4 knockdown through EphB4 shRNA inhibited EPO-mediated osteoblastic phenotypes. Furthermore, in vivo assays clearly demonstrated that EPO efficiently induces new bone formation in the alveolar bone regeneration model. Taken together, these results suggest that ephrinB2/EphB4 signaling may play an important role in EPO-mediated bone formation.

  11. Erythropoietin couples erythropoiesis, B-lymphopoiesis, and bone homeostasis within the bone marrow microenvironment.

    PubMed

    Singbrant, Sofie; Russell, Megan R; Jovic, Tanja; Liddicoat, Brian; Izon, David J; Purton, Louise E; Sims, Natalie A; Martin, T John; Sankaran, Vijay G; Walkley, Carl R

    2011-05-26

    Erythropoietin (Epo) has been used in the treatment of anemia resulting from numerous etiologies, including renal disease and cancer. However, its effects are controversial and the expression pattern of the Epo receptor (Epo-R) is debated. Using in vivo lineage tracing, we document that within the hematopoietic and mesenchymal lineage, expression of Epo-R is essentially restricted to erythroid lineage cells. As expected, adult mice treated with a clinically relevant dose of Epo had expanded erythropoiesis because of amplification of committed erythroid precursors. Surprisingly, we also found that Epo induced a rapid 26% loss of the trabecular bone volume and impaired B-lymphopoiesis within the bone marrow microenvironment. Despite the loss of trabecular bone, hematopoietic stem cell populations were unaffected. Inhibition of the osteoclast activity with bisphosphonate therapy blocked the Epo-induced bone loss. Intriguingly, bisphosphonate treatment also reduced the magnitude of the erythroid response to Epo. These data demonstrate a previously unrecognized in vivo regulatory network coordinating erythropoiesis, B-lymphopoiesis, and skeletal homeostasis. Importantly, these findings may be relevant to the clinical application of Epo.

  12. The effect of erythropoietin on autologous stem cell-mediated bone regeneration.

    PubMed

    Nair, Ashwin M; Tsai, Yi-Ting; Shah, Krishna M; Shen, Jinhui; Weng, Hong; Zhou, Jun; Sun, Xiankai; Saxena, Ramesh; Borrelli, Joseph; Tang, Liping

    2013-10-01

    Mesenchymal stem cells (MSCs) although used for bone tissue engineering are limited by the requirement of isolation and culture prior to transplantation. Our recent studies have shown that biomaterial implants can be engineered to facilitate the recruitment of MSCs. In this study, we explore the ability of these implants to direct the recruitment and the differentiation of MSCs in the setting of a bone defect. We initially determined that both stromal derived factor-1alpha (SDF-1α) and erythropoietin (Epo) prompted different degrees of MSC recruitment. Additionally, we found that Epo and bone morphogenetic protein-2 (BMP-2), but not SDF-1α, triggered the osteogenic differentiation of MSCs in vitro. We then investigated the possibility of directing autologous MSC-mediated bone regeneration using a murine calvaria model. Consistent with our in vitro observations, Epo-releasing scaffolds were found to be more potent in bridging the defect than BMP-2 loaded scaffolds, as determined by computed tomography (CT) scanning, fluorescent imaging and histological analyses. These results demonstrate the tremendous potential, directing the recruitment and differentiation of autologous MSCs has in the field of tissue regeneration.

  13. Fibronectin potentiates topical erythropoietin-induced wound repair in diabetic mice.

    PubMed

    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.

  14. A critical role of erythropoietin receptor in neurogenesis and post-stroke recovery.

    PubMed

    Tsai, Peter T; Ohab, John J; Kertesz, Nathalie; Groszer, Matthias; Matter, Cheryl; Gao, Jing; Liu, Xin; Wu, Hong; Carmichael, S Thomas

    2006-01-25

    Erythropoietin (EPO) is the principal growth factor regulating the production of red blood cells. Recent studies demonstrated that exogenous EPO acts as a neuroprotectant and regulates neurogenesis. Using a genetic approach, we evaluate the roles of endogenous EPO and its classical receptor (EPOR) in mammalian neurogenesis. We demonstrate severe and identical embryonic neurogenesis defects in animals null for either the Epo or EpoR gene, suggesting that the classical EPOR is essential for EPO action during embryonic neurogenesis. Furthermore, by generating conditional EpoR knock-down animals, we demonstrate that brain-specific deletion of EpoR leads to significantly reduced cell proliferation in the subventricular zone and impaired post-stroke neurogenesis. EpoR conditional knockdown leads to a specific deficit in post-stroke neurogenesis through impaired migration of neuroblasts to the peri-infarct cortex. Our results suggest that both EPO and EPOR are essential for early embryonic neural development and that the classical EPOR is important for adult neurogenesis and for migration of regenerating neurons during post-injury recovery.

  15. The nonhematopoietic effects of erythropoietin in skin regeneration and repair: from basic research to clinical use.

    PubMed

    Sorg, Heiko; Harder, Yves; Krueger, Christian; Reimers, Kerstin; Vogt, Peter M

    2013-05-01

    Erythropoietin (EPO) is the main regulator of red blood cell production but there exists also a variety of nonhematopoietic properties. More recent data show that EPO is also associated with the protection of tissues suffering from ischemia and reperfusion injury as well as with improved regeneration in various organ systems, in particular the skin. This review highlights the mechanisms of EPO in the different stages of wound healing and the reparative processes in the skin emphasizing pathophysiological mechanisms and potential clinical applications. There is clear evidence that EPO effectively influences all wound-healing phases in a dose-dependent manner. This includes inflammation, tissue, and blood vessel formation as well as the remodeling of the wound. The molecular mechanism is predominantly based on an increased expression of the endothelial and inducible nitric oxide (NO) synthase with a consecutive rapid supply of NO as well as an increased content of vascular endothelial growth factor (VEGF) in the wound. The improved understanding of the functions and regulatory mechanisms of EPO in the context of wound-healing problems and ischemia/reperfusion injury, especially during flap surgery, may lead to new considerations of this growth hormone for its regular clinical application in patients.

  16. Erythropoietin improves skin wound healing and activates the TGF-β signaling pathway.

    PubMed

    Siebert, Nikolai; Xu, Weiguo; Grambow, Eberhard; Zechner, Dietmar; Vollmar, Brigitte

    2011-12-01

    We could recently report that erythropoietin (EPO) accelerates skin wound healing in mice. Now, we provide insight into the molecular mechanisms of this non-hematopoietic property of EPO analyzing the transforming growth factor (TGF)-β signaling pathway. EPO receptor was found expressed in both non-wounded and wounded skin tissue as well as in fibroblasts and keratinocytes. In saline-treated control animals, wounds exhibited a significant upregulation of TGF-β1 and of α-smooth muscle actin (α-SMA) compared with non-wounded skin. EPO treatment accelerated wound epithelialization and induced mRNA expression of TGF-β1 and α-SMA. In addition, EPO significantly enhanced phosphorylation of Smad2 and Smad3 in fibroblasts and also elevated phosphorylation of Smad3 in wound tissue. Blockade of TGF-β using a neutralizing anti-TGF-β antibody attenuated EPO-induced acceleration of wound epithelialization in vivo and markedly reversed EPO effects on mRNA expression of TGF-β1 and α-SMA. In conclusion, EPO caused activation of the Smad-dependent TGF-β signaling pathway, enhanced differentiation of myofibroblasts, and accelerated skin wound closure.

  17. Interactive role of trauma cytokines and erythropoietin and their therapeutic potential for acute and chronic wounds.

    PubMed

    Bader, Augustinus; Lorenz, Katrin; Richter, Anja; Scheffler, Katja; Kern, Larissa; Ebert, Sabine; Giri, Shibashish; Behrens, Maria; Dornseifer, Ulf; Macchiarini, Paolo; Machens, Hans-Günther

    2011-02-01

    If controllable, stem cell activation following injury has the therapeutic potential for supporting regeneration in acute or chronic wounds. Human dermally-derived stem cells (FmSCs) were exposed to the cytokines interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α) in the presence of erythropoietin (EPO). Cells were cultured under ischemic conditions and phenotypically characterized using flow cytometry. Topical EPO application was performed in three independent clinical wound healing attempts. The FmSCs expressed the receptor for EPO. EPO had a strong inhibitory effect on FmSC growth in the absence of IL-6 and TNF-α. With IL-6, the EPO effects were reversed to that of growth stimulation. TNF-α had the strongest stimulatory effect. In contrast, IL-1β had an inhibitory effect. Topically applied EPO considerably enhanced wound healing and improved wound conditions of acute and chronic wounds. Site specificity of stem cell activation is mediated by IL-6 and TNF-α. In trauma, EPO ceases its inhibitory role and reverts to a clinically relevant boosting function. EPO may be an important therapeutic tool for the topical treatment of acute and chronic wounds.

  18. Investigation of the protective effect of erythropoietin on spinal cord injury in rats.

    PubMed

    Hong, Zhenghua; Hong, Huaxing; Chen, Haixiao; Wang, Zhangfu; Hong, Dun

    2011-09-01

    Erythropoietin (EPO) is a promising therapeutic agent used in a variety of spinal cord injuries. Therefore, identifying the specific molecular pathway mediating the neuronal protective effect of EPO after spinal cord injury (SCI) is of great value to the patients concerned. Platelet-derived growth factor (PDGF)-B is an important factor in the recovery of neurological function. We explored changes in the expression of PDGF-B in spinal cord injury rats after receiving EPO treatment. We used a weight-drop contusion SCI model, and EPO treatment group rats received single doses of EPO (1,000 U/kg i.p.) immediately after the operation. Seven days after the operation, the results revealed a more rapid recovery as noted by the higher BBB scores, less disruption and more neuronal regeneration of the spinal cord in the EPO treatment group than that in the SCI group. PDGF-B expression also increased in the EPO treatment group compared to that in the SCI group (P<0.01). This study showed that PDGF-B plays a role in the neuronal protective effect of EPO on spinal cord injury in rats, which may help to explain the quick recovery after EPO treatment of spinal cord injury.

  19. Specific contribution of the erythropoietin gene 3' enhancer to hepatic erythropoiesis after late embryonic stages.

    PubMed

    Suzuki, Norio; Obara, Naoshi; Pan, Xiaoqing; Watanabe, Miho; Jishage, Kou-Ichi; Minegishi, Naoko; Yamamoto, Masayuki

    2011-09-01

    Erythropoietin (Epo) is secreted from the liver and kidney, where Epo production is strictly regulated at the transcriptional level in a hypoxia- and/or anemia-inducible manner. Here, we examined the in vivo function of the enhancer located 3' to the Epo gene (EpoE-3'). Reporter transgenic-mouse analyses revealed that the EpoE-3' enhancer is necessary and sufficient for the liver-specific and hypoxia-responsive expression of the gene after embryonic day 14.5 (E14.5). However, the enhancer is dispensable for Epo gene expression in the kidney and early-stage embryonic liver. Genetic removal of EpoE-3' from the endogenous Epo gene resulted in mice with severe anemia at late embryonic and neonatal stages due to defects in hepatic erythropoiesis, but early hepatic and splenic erythropoiesis was not affected. The mutant mice recover from the anemia in the juvenile period when major Epo production switches from the liver to the kidney. These results demonstrate that EpoE-3' is necessary for late hepatic erythropoiesis by specifically supporting paracrine production of Epo in the liver. In contrast, Epo production in the kidney utilizes distinct regulatory machinery and supports erythropoiesis in the bone marrow and spleen in adult animals.

  20. Distinct subpopulations of FOXD1 stroma-derived cells regulate renal erythropoietin.

    PubMed

    Kobayashi, Hanako; Liu, Qingdu; Binns, Thomas C; Urrutia, Andres A; Davidoff, Olena; Kapitsinou, Pinelopi P; Pfaff, Andrew S; Olauson, Hannes; Wernerson, Annika; Fogo, Agnes B; Fong, Guo-Hua; Gross, Kenneth W; Haase, Volker H

    2016-05-02

    Renal peritubular interstitial fibroblast-like cells are critical for adult erythropoiesis, as they are the main source of erythropoietin (EPO). Hypoxia-inducible factor 2 (HIF-2) controls EPO synthesis in the kidney and liver and is regulated by prolyl-4-hydroxylase domain (PHD) dioxygenases PHD1, PHD2, and PHD3, which function as cellular oxygen sensors. Renal interstitial cells with EPO-producing capacity are poorly characterized, and the role of the PHD/HIF-2 axis in renal EPO-producing cell (REPC) plasticity is unclear. Here we targeted the PHD/HIF-2/EPO axis in FOXD1 stroma-derived renal interstitial cells and examined the role of individual PHDs in REPC pool size regulation and renal EPO output. Renal interstitial cells with EPO-producing capacity were entirely derived from FOXD1-expressing stroma, and Phd2 inactivation alone induced renal Epo in a limited number of renal interstitial cells. EPO induction was submaximal, as hypoxia or pharmacologic PHD inhibition further increased the REPC fraction among Phd2-/- renal interstitial cells. Moreover, Phd1 and Phd3 were differentially expressed in renal interstitium, and heterozygous deficiency for Phd1 and Phd3 increased REPC numbers in Phd2-/- mice. We propose that FOXD1 lineage renal interstitial cells consist of distinct subpopulations that differ in their responsiveness to Phd2 inactivation and thus regulation of HIF-2 activity and EPO production under hypoxia or conditions of pharmacologic or genetic PHD inactivation.

  1. Hypoxia-inducible factor regulates hepcidin via erythropoietin-induced erythropoiesis.

    PubMed

    Liu, Qingdu; Davidoff, Olena; Niss, Knut; Haase, Volker H

    2012-12-01

    Iron demand in bone marrow increases when erythropoiesis is stimulated by hypoxia via increased erythropoietin (EPO) synthesis in kidney and liver. Hepcidin, a small polypeptide produced by hepatocytes, plays a central role in regulating iron uptake by promoting internalization and degradation of ferroportin, the only known cellular iron exporter. Hypoxia suppresses hepcidin, thereby enhancing intestinal iron uptake and release from internal stores. While HIF, a central mediator of cellular adaptation to hypoxia, directly regulates renal and hepatic EPO synthesis under hypoxia, the molecular basis of hypoxia/HIF-mediated hepcidin suppression in the liver remains unclear. Here, we used a genetic approach to disengage HIF activation from EPO synthesis and found that HIF-mediated suppression of the hepcidin gene (Hamp1) required EPO induction. EPO induction was associated with increased erythropoietic activity and elevated serum levels of growth differentiation factor 15. When erythropoiesis was inhibited pharmacologically, Hamp1 was no longer suppressed despite profound elevations in serum EPO, indicating that EPO by itself is not directly involved in Hamp1 regulation. Taken together, we provide in vivo evidence that Hamp1 suppression by the HIF pathway occurs indirectly through stimulation of EPO-induced erythropoiesis.

  2. Development of Erythroid Progenitors under Erythropoietin Stimulation in Xenopus laevis Larval Liver.

    PubMed

    Okui, Takehito; Hosozawa, Sakiko; Kohama, Satoka; Fujiyama, Shingo; Maekawa, Shun; Muto, Hiroshi; Kato, Takashi

    2016-12-01

    Erythroid progenitors that respond to erythropoietin (Epo) are present in the liver of adult Xenopus laevis. However, cells responding to Epo in the larval liver and through the metamorphosis period under hepatic remodeling have not been characterized. In this study, tadpoles were staged using the tables of Nieuwkoop and Faber (NF). Liver cells from pre- (NF56) or post- (NF66) metamorphic stage were cultured in the presence of Epo. β2-globin mRNA expression peaked at day 7 after the start of culture. Larval β2-globin was highly expressed in NF56-derived cells, while adult β2-globinwas detected in those of NF66. In both NF56- and NF66-derived cells, mRNA expression of eporand gata2 peaked at day 5 and days 3-4, respectively. In contrast, gata1 expression peaked at day 6 in NF56 cells and at day 5 in NF66 cells. Half maximal proliferation of erythrocytic blast cells derived from the liver at NF66 was observed at day 3, which was earlier than that of NF56. These results indicate that erythroid progenitors that respond to Xenopus laevis Epo are maintained in pre- and post-metamorphic liver, although the tissue architecture changes dramatically during metamorphosis. Additionally, the globin switching occurred, and/or the erythroid progenitors for larval erythrocytes were replaced by those for adult erythrocytes in the metamorphic liver.

  3. Impaired erythropoietin production in liver transplant recipients: the role of calcineurin inhibitors.

    PubMed

    Bardet, Valérie; Junior, Alcindo Pissaia; Coste, Joël; Lecoq-Lafon, Carinne; Chouzenoux, Sandrine; Bernard, Denis; Soubrane, Olivier; Lacombe, Catherine; Calmus, Yvon; Conti, Filoména

    2006-11-01

    Anemia is common following liver transplantation. Because cyclosporine inhibits erythropoietin (Epo) production in experimental models, we investigated whether Epo production was impaired in liver transplant recipients receiving a cyclosporine- or tacrolimus-based immunosuppressive regimen. First, serum Epo levels were measured before and 1 year after transplantation in 35 liver transplant recipients. Second, serum Epo levels were compared in a large series of liver transplant recipients with stable graft and renal functions: 27 receiving a cyclosporine-based and 31 receiving a tacrolimus-based immunosuppressive regimen. A reference group was made up of 22 blood donors and 21 nontransplanted subjects with iron-deficiency anemia. Serum Epo levels were significantly lower after than before liver transplantation, especially in cyclosporine-treated patients. Serum Epo concentrations correlated with hematocrit values in both transplant recipients and control subjects. Using multiple linear regression models, the polynomial relationship between hematocrit and serum Epo values was similar to the control group in patients under tacrolimus, whereas Epo production was significantly reduced in patients under cyclosporine-based immunosuppression. Hematocrit values and the type of calcineurin inhibitor were the only parameters independently related to Epo levels. In conclusion, cyclosporine, but not tacrolimus, inhibits Epo production at the doses used in clinical practice.

  4. Renal epithelium regulates erythropoiesis via HIF-dependent suppression of erythropoietin

    PubMed Central

    Farsijani, Navid M.; Liu, Qingdu; Davidoff, Olena; Sha, Feng; Fandrey, Joachim; Ikizler, T. Alp; O’Connor, Paul M.

    2016-01-01

    The adult kidney plays a central role in erythropoiesis and is the main source of erythropoietin (EPO), an oxygen-sensitive glycoprotein that is essential for red blood cell production. Decreases of renal pO2 promote hypoxia-inducible factor 2–mediated (HIF-2–mediated) induction of EPO in peritubular interstitial fibroblast-like cells, which serve as the cellular site of EPO synthesis in the kidney. It is not clear whether HIF signaling in other renal cell types also contributes to the regulation of EPO production. Here, we used a genetic approach in mice to investigate the role of renal epithelial HIF in erythropoiesis. Specifically, we found that HIF activation in the proximal nephron via induced inactivation of the von Hippel–Lindau tumor suppressor, which targets the HIF-α subunit for proteasomal degradation, led to rapid development of hypoproliferative anemia that was associated with a reduction in the number of EPO-producing renal interstitial cells. Moreover, suppression of renal EPO production was associated with increased glucose uptake, enhanced glycolysis, reduced mitochondrial mass, diminished O2 consumption, and elevated renal tissue pO2. Our genetic analysis suggests that tubulointerstitial cellular crosstalk modulates renal EPO production under conditions of epithelial HIF activation in the kidney. PMID:26927670

  5. Erythropoietin employs cell longevity pathways of SIRT1 to foster endothelial vascular integrity during oxidant stress.

    PubMed

    Hou, Jinling; Wang, Shaohui; Shang, Yan Chen; Chong, Zhao Zhong; Maiese, Kenneth

    2011-08-01

    Given the cytoprotective ability of erythropoietin (EPO) in cerebral microvascular endothelial cells (ECs) and the invaluable role of ECs in the central nervous system, it is imperative to elucidate the cellular pathways for EPO to protect ECs against brain injury. Here we illustrate that EPO relies upon the modulation of SIRT1 (silent mating type information regulator 2 homolog 1) in cerebral microvascular ECs to foster cytoprotection during oxygen-glucose deprivation (OGD). SIRT1 activation which results in the inhibition of apoptotic early membrane phosphatidylserine (PS) externalization and subsequent DNA degradation during OGD becomes a necessary component for EPO protection in ECs, since inhibition of SIRT1 activity or diminishing its expression by gene silencing abrogates cell survival supported by EPO during OGD. Furthermore, EPO promotes the subcellular trafficking of SIRT1 to the nucleus which is necessary for EPO to foster vascular protection. EPO through SIRT1 averts apoptosis through activation of protein kinase B (Akt1) and the phosphorylation and cytoplasmic retention of the forkhead transcription factor FoxO3a. SIRT1 through EPO activation also utilizes mitochondrial pathways to prevent mitochondrial depolarization, cytochrome c release, and Bad, caspase 1, and caspase 3 activation. Our work identifies novel pathways for EPO in the vascular system that can govern the activity of SIRT1 to prevent apoptotic injury through Akt1, FoxO3a phosphorylation and trafficking, mitochondrial membrane permeability, Bad activation, and caspase 1 and 3 activities in ECs during oxidant stress.

  6. Comparison of the Protective Effects of Erythropoietin and Melatonin on Renal Ischemia-Reperfusion Injury

    PubMed Central

    Banaei, Shokofeh; Ahmadiasl, Nasser; Alihemmati, Alireza

    2016-01-01

    Background 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. Objectives 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. Materials and Methods 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. Results 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. Conclusions 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. PMID:27921018

  7. Cord blood erythropoietin and interleukin-6 for prediction of intraventricular hemorrhage in the preterm neonate

    PubMed Central

    BHANDARI, VINEET; BUHIMSCHI, CATALIN S.; HAN, CHRISTINA S.; LEE, SARAH Y.; PETTKER, CHRISTIAN M.; CAMPBELL, KATHERINE H.; DULAY, ANTONETTE T.; OLIVER, EMILY A.; WERNER, ERIKA F.; BUHIMSCHI, IRINA A.

    2013-01-01

    Objective To evaluate cord blood erythropoietin (EPO) and interleukin-6 (IL-6) levels to predict preterm infants at risk of developing intraventricular hemorrhage (IVH). Methods Levels of umbilical cord EPO, acid–base status and IL-6 were analyzed in 116 consecutive, preterm newborns (GA at delivery: 29 [23–34] weeks) born to mothers who had a clinically indicated amniocentesis to rule out infection. Early-onset neonatal sepsis (EONS) was diagnosed using symptoms, hematological criteria and blood cultures. Results IVH was diagnosed by cranial ultrasounds. The prevalence of IVH in our population was 25% (29/116). There was a direct relationship between cord blood EPO and cord blood IL-6 concentration (r = 0.225, p = 0.014), independent of GA at birth. Elevated cord blood EPO levels (r = 0.182, p = 0.016) and GA birth at birth (r = –0.236, p = 0.004) remained significant independent factors associated with the risk of IVH, when evaluated with stepwise logistic regression analyses. Cord blood IL-6, pH, and EONS were not associated with IVH. These relationships remained following correction for GA at birth (p = 0.027). Conclusions Our results suggest that elevation in cord blood EPO may predict newborns at risk for IVH, independent of fetal inflammatory status. Further studies are warranted to confirm this association. PMID:20937006

  8. A gene responsible for prolyl-hydroxylation of moss-produced recombinant human erythropoietin

    PubMed Central

    Parsons, Juliana; Altmann, Friedrich; Graf, Manuela; Stadlmann, Johannes; Reski, Ralf; Decker, Eva L.

    2013-01-01

    Recombinant production of pharmaceutical proteins is crucial, not only for personalized medicine. While most biopharmaceuticals are currently produced in mammalian cell culture, plant-made pharmaceuticals gain momentum. Post-translational modifications in plants are similar to those in humans, however, existing differences may affect quality, safety and efficacy of the products. A frequent modification in higher eukaryotes is prolyl-4-hydroxylase (P4H)-catalysed prolyl-hydroxylation. P4H sequence recognition sites on target proteins differ between humans and plants leading to non-human posttranslational modifications of recombinant human proteins produced in plants. The resulting hydroxyprolines display the anchor for plant-specific O-glycosylation, which bears immunogenic potential for patients. Here we describe the identification of a plant gene responsible for non-human prolyl-hydroxylation of human erythropoietin (hEPO) recombinantly produced in plant (moss) bioreactors. Targeted ablation of this gene abolished undesired prolyl-hydroxylation of hEPO and thus paves the way for plant-made pharmaceuticals humanized via glyco-engineering in moss bioreactors. PMID:24145658

  9. Salmonella Infection Enhances Erythropoietin Production by the Kidney and Liver, Which Correlates with Elevated Bacterial Burdens.

    PubMed

    Li, Lin-Xi; Benoun, Joseph M; Weiskopf, Kipp; Garcia, K Christopher; McSorley, Stephen J

    2016-10-01

    Salmonella infection profoundly affects host erythroid development, but the mechanisms responsible for this effect remain poorly understood. We monitored the impact of Salmonella infection on erythroid development and found that systemic infection induced anemia, splenomegaly, elevated erythropoietin (EPO) levels, and extramedullary erythropoiesis in a process independent of Salmonella pathogenicity island 2 (SPI2) or flagellin. The circulating EPO level was also constitutively higher in mice lacking the expression of signal-regulatory protein α (SIRPα). The expression level of EPO mRNA was elevated in the kidney and liver but not increased in the spleens of infected mice despite the presence of extramedullary erythropoiesis in this tissue. In contrast to data from a previous report, mice lacking EPO receptor (EPOR) expression on nonerythroid cells (EPOR rescued) had bacterial loads similar to those of wild-type mice following Salmonella infection. Indeed, treatment to reduce splenic erythroblasts and mature red blood cells correlated with elevated bacterial burdens, implying that extramedullary erythropoiesis benefits the host. Together, these findings emphasize the profound effect of Salmonella infection on erythroid development and suggest that the modulation of erythroid development has both positive and negative consequences for host immunity.

  10. Improvement of in vivo efficacy of recombinant human erythropoietin by encapsulation in PEG–PLA micelle

    PubMed Central

    Shi, Yanan; Huang, Wan; Liang, Rongcai; Sun, Kaoxiang; Zhang, Fangxi; Liu, Wanhui; Li, Youxin

    2013-01-01

    To improve the pharmacokinetics and stability of recombinant human erythropoietin (rhEPO), rhEPO was successfully formulated into poly(ethylene glycol)–poly(d,l-lactide) (PEG–PLA) di-block copolymeric micelles at diameters ranging from 60 to 200 nm with narrow polydispersity indices (PDIs; PDI < 0.3) and trace amount of protein aggregation. The zeta potential of the spherical micelles was in the range of −3.78 to 4.65 mV and the highest encapsulation efficiency of rhEPO in the PEG–PLA micelles was about 80%. In vitro release profiles indicated that the stability of rhEPO in the micelles was improved significantly and only a trace amount of aggregate was found. Pharmacokinetic studies in rats showed highly enhanced plasma retention time of the rhEPO-loaded PEG-PLA micelles in comparison with the native rhEPO group. Increased hemoglobin concentrations were also found in the rat study. Native polyacrylamide gel electrophoresis results demonstrated that rhEPO was successfully encapsulated into the micelles, which was stable in phosphate buffered saline with different pHs and concentrations of NaCl. Therefore, PEG–PLA micelles can be a potential protein drug delivery system. PMID:23293515

  11. Sorting of growth hormone-erythropoietin fusion proteins in rat salivary glands.

    PubMed

    Samuni, Yuval; Zheng, Changyu; Cawley, Niamh X; Cotrim, Ana P; Loh, Y Peng; Baum, Bruce J

    2008-08-15

    Neuroendocrine and exocrine cells secrete proteins in either a constitutive manner or via the regulated secretory pathway (RSP), but the specific sorting mechanisms involved are not fully understood. After gene transfer to rat salivary glands, the transgenic model proteins human growth hormone (hGH) and erythropoietin (hEpo) are secreted primarily into saliva (RSP; exocrine) and serum (constitutive; endocrine), respectively. We hypothesized that fusion of hGH at either the C-terminus or the N-terminus of hEpo would re-direct hEpo from the bloodstream into saliva. We constructed and expressed two fusion proteins, hEpo-hGH and hGH-hEpo, using serotype 5-adenoviral vectors, and delivered them to rat submandibular glands in vivo via retroductal cannulation. Both the hEpo-hGH and hGH-hEpo fusion proteins, but not hEpo alone, were secreted primarily into saliva (p<0.0001 and p=0.0083, respectively). These in vivo studies demonstrate for the first time that hGH, in an N- as well as C-terminal position, influences the secretion of a constitutive pathway protein.

  12. Erythropoietin Signaling: A Novel Regulator of White Adipose Tissue Inflammation During Diet-Induced Obesity

    PubMed Central

    Alnaeeli, Mawadda; Raaka, Bruce M.; Gavrilova, Oksana; Teng, Ruifeng; Chanturiya, Tatyana

    2014-01-01

    Obesity-induced white adipose tissue (WAT) inflammation and insulin resistance are associated with macrophage (Mф) infiltration and phenotypic shift from “anti-inflammatory” M2-like to predominantly “proinflammatory” M1-like cells. Erythropoietin (EPO), a glycoprotein hormone indispensable for erythropoiesis, has biological activities that extend to nonerythroid tissues, including antiapoptotic and anti-inflammatory effects. Using comprehensive in vivo and in vitro analyses in mice, EPO treatment inhibited WAT inflammation, normalized insulin sensitivity, and reduced glucose intolerance. We investigated EPO receptor (EPO-R) expression in WAT and characterized the role of its signaling during obesity-induced inflammation. Remarkably, and prior to any detectable changes in body weight or composition, EPO treatment reduced M1-like Mф and increased M2-like Mф in WAT, while decreasing inflammatory monocytes. These anti-inflammatory effects were found to be driven, at least in part, by direct EPO-R response in Mф via Stat3 activation, where EPO effects on M2 but not M1 Mф required interleukin-4 receptor/Stat6. Using obese ∆EpoR mice with EPO-R restricted to erythroid cells, we demonstrated an anti-inflammatory role for endogenous EPO. Collectively, our findings identify EPO-R signaling as a novel regulator of WAT inflammation, extending its nonerythroid activity to encompass effects on both Mф infiltration and subset composition in WAT. PMID:24647735

  13. Human fetal liver stromal cells expressing erythropoietin promote hematopoietic development from human embryonic stem cells.

    PubMed

    Yang, Chao; Ji, Lei; Yue, Wen; Shi, Shuang-Shuang; Wang, Ruo-Yong; Li, Yan-Hua; Xie, Xiao-Yan; Xi, Jia-Fei; He, Li-Juan; Nan, Xue; Pei, Xue-Tao

    2012-02-01

    Blood cells transfusion and hematopoietic stem cells (HSCs) transplantation are important methods for cell therapy. They are widely used in the treatment of incurable hematological disorder, infectious diseases, genetic diseases, and immunologic deficiency. However, their availability is limited by quantity, capacity of proliferation and the risk of blood transfusion complications. Recently, human embryonic stem cells (hESCs) have been shown to be an alternative resource for the generation of hematopoietic cells. In the current study, we describe a novel method for the efficient production of hematopoietic cells from hESCs. The stable human fetal liver stromal cell lines (hFLSCs) expressing erythropoietin (EPO) were established using the lentiviral system. We observed that the supernatant from the EPO transfected hFLSCs could induce the hESCs differentiation into hematopoietic cells, especially erythroid cells. They not only expressed fetal and embryonic globins but also expressed the adult-globin chain on further maturation. In addition, these hESCs-derived erythroid cells possess oxygen-transporting capacity, which indicated hESCs could generate terminally mature progenies. This should be useful for ultimately developing an animal-free culture system to generate large numbers of erythroid cells from hESCs and provide an experimental model to study early human erythropoiesis.

  14. Statins inhibited erythropoietin-induced proliferation of rat vascular smooth muscle cells.

    PubMed

    Kaneda, Tae; Tsuruoka, Shuichi; Fujimura, Akio

    2010-12-15

    Erythropoietin (EPO) directly stimulates the proliferation of vascular smooth muscle cells, and this is believed to be one of the mechanisms of vascular access failure of hemodialysis patients. However, precise mechanisms of the EPO-induced proliferation of vascular smooth muscle cells are not certain. HMG-CoA reductase inhibitors (statins) are primarily used to reduce cholesterol levels, but also exert other effects, including reno-protective effects. We evaluated the effect of several statins with various hydrophilicities on the EPO-induced proliferation of primary cultured rat vascular smooth muscle cells (VSMCs) in vitro. EPO significantly and concentration-dependently increased DNA synthesis as assessed by [³H]thymidine incorporation, cell proliferation as assessed by WST-1 assay, and activation of the p44/42MAPK pathway. Therapeutic doses of statins (pravastatin, simvastatin, atorvastatin and fluvastatin) in patients with hypercholesterolemia almost completely suppressed all of the EPO-induced effects in a concentration-dependent manner. Co-addition of mevalonic acid almost completely reversed the effects of statins. Statin alone did not affect the basal proliferation capacity of the cells. The effects were almost similar among the statins. We concluded that statins inhibited EPO-induced proliferation in rat VSMCs at least partly through their inhibition of HMG-CoA reductase activity. In the future, statins might prove useful for the treatment of EPO-induced hyperplasia of vascular access. Because the statins all showed comparable effects irrespective of their hydrophilicities, these effects might be a class effect.

  15. Salmonella Infection Enhances Erythropoietin Production by the Kidney and Liver, Which Correlates with Elevated Bacterial Burdens

    PubMed Central

    Li, Lin-Xi; Benoun, Joseph M.; Weiskopf, Kipp; Garcia, K. Christopher

    2016-01-01

    Salmonella infection profoundly affects host erythroid development, but the mechanisms responsible for this effect remain poorly understood. We monitored the impact of Salmonella infection on erythroid development and found that systemic infection induced anemia, splenomegaly, elevated erythropoietin (EPO) levels, and extramedullary erythropoiesis in a process independent of Salmonella pathogenicity island 2 (SPI2) or flagellin. The circulating EPO level was also constitutively higher in mice lacking the expression of signal-regulatory protein α (SIRPα). The expression level of EPO mRNA was elevated in the kidney and liver but not increased in the spleens of infected mice despite the presence of extramedullary erythropoiesis in this tissue. In contrast to data from a previous report, mice lacking EPO receptor (EPOR) expression on nonerythroid cells (EPOR rescued) had bacterial loads similar to those of wild-type mice following Salmonella infection. Indeed, treatment to reduce splenic erythroblasts and mature red blood cells correlated with elevated bacterial burdens, implying that extramedullary erythropoiesis benefits the host. Together, these findings emphasize the profound effect of Salmonella infection on erythroid development and suggest that the modulation of erythroid development has both positive and negative consequences for host immunity. PMID:27456828

  16. Resistance to Recombinant Human Erythropoietin Therapy in a Rat Model of Chronic Kidney Disease Associated Anemia.

    PubMed

    Garrido, Patrícia; Ribeiro, Sandra; Fernandes, João; Vala, Helena; Rocha-Pereira, Petronila; Bronze-da-Rocha, Elsa; Belo, Luís; Costa, Elísio; Santos-Silva, Alice; Reis, Flávio

    2015-12-25

    This study aimed to elucidate the mechanisms explaining the persistence of anemia and resistance to recombinant human erythropoietin (rHuEPO) therapy in a rat model of chronic kidney disease (CKD)-associated anemia with formation of anti-rHuEPO antibodies. The remnant kidney rat model of CKD induced by 5/6 nephrectomy was used to test a long-term (nine weeks) high dose of rHuEPO (200 UI/kg bw/week) treatment. Hematological and biochemical parameters were evaluated as well as serum and tissue (kidney, liver and/or duodenum) protein and/or gene expression of mediators of erythropoiesis, iron metabolism and tissue hypoxia, inflammation, and fibrosis. Long-term treatment with a high rHuEPO dose is associated with development of resistance to therapy as a result of antibodies formation. In this condition, serum EPO levels are not deficient and iron availability is recovered by increased duodenal absorption. However, erythropoiesis is not stimulated, and the resistance to endogenous EPO effect and to rHuEPO therapy results from the development of a hypoxic, inflammatory and fibrotic milieu in the kidney tissue. This study provides new insights that could be important to ameliorate the current therapeutic strategies used to treat patients with CKD-associated anemia, in particular those that become resistant to rHuEPO therapy.

  17. Erythropoietin acts as an anti-inflammatory signal on murine mast cells.

    PubMed

    Wiedenmann, Tanja; Ehrhardt, Stefanie; Cerny, Daniela; Hildebrand, Dagmar; Klein, Sabrina; Heeg, Klaus; Kubatzky, Katharina F

    2015-05-01

    Recently it was found that the erythropoietin receptor (EpoR) is expressed on innate immune cells, such as dendritic cells and macrophages. We found that murine bone marrow-derived mast cells express the EpoR and that its expression is increased under hypoxic conditions. Interestingly, Epo stimulation of the cells did not activate signal transducer and activator of transcription molecules, nor did we find differences in the expression of typical STAT-dependent genes, the proliferation rate, and the ability to differentiate or to protect the cells from apoptosis. Instead, we demonstrate that stimulation of mast cells with Epo leads to phosphorylation of the receptor tyrosine kinase c-kit. We hypothesize that this is due to the formation of a receptor complex between the EpoR and c-kit. The common beta chain of the IL-3 receptor family, which was described as part of the tissue protective receptor (TPR) on other non-erythroid cells, however is not activated. To investigate whether the EpoR/c-kit complex has tissue protective properties, cells were treated with the Toll-like receptor ligand LPS. Combined Epo and LPS treatment downregulated the inflammatory response of the cells as detected by a decrease in IL-6 and TNF-α secretion.

  18. Erythropoietin enhances neurogenesis and restores spatial memory in rats after traumatic brain injury.

    PubMed

    Lu, Dunyue; Mahmood, Asim; Qu, Changsheng; Goussev, Anton; Schallert, Timothy; Chopp, Michael

    2005-09-01

    Erythropoietin (EPO) is neuroprotective in models of stroke and traumatic brain injury (TBI) when administered prior to or within the first few hours after injury. We seek to demonstrate that EPO also has neurorestorative effects when administered late (i.e., 1 day) after TBI in the rat. Twelve rats were subjected to TBI. Six rats were treated with EPO daily for 14 days starting 1 day after injury, and an additional six rats were treated with saline. Bromodeoxyuridine (BrdU) was administered daily for 14 days. Memory tests using a Morris Water Maze were performed prior to and after injury and treatment. Animals were sacrificed at 15 days after TBI, and their brains were prepared for histological analysis of damage to the dentate gyrus (DG) and for evaluation of newly formed neurons using double labeling of BrdU and MAP-2. The data revealed a significant improvement in spatial memory and significant increase in the number of newly formed neurons with EPO treatment compared with control animals. These data suggest that EPO treatment initiated 1 day after TBI is neurorestorative by enhancing neurogenesis, as well as neuroprotective.

  19. Beneficial Effect of Erythropoietin Short Peptide on Acute Traumatic Brain Injury.

    PubMed

    Wang, Bo; Kang, Mitchell; Marchese, Michelle; Rodriguez, Esther; Lu, Wei; Li, Xintong; Maeda, Yasuhiro; Dowling, Peter

    2016-04-01

    There is currently no effective medical treatment for traumatic brain injury (TBI). Beyond the immediate physical damage caused by the initial impact, additional damage evolves due to the inflammatory response that follows brain injury. Here we show that therapy with JM4, a low molecular weight 19-amino acid nonhematopoietic erythropoietin (EPO) peptidyl fragment, containing amino acids 28-46 derived from the first loop of EPO, markedly reduces acute brain injury. Mice underwent controlled cortical injury and received either whole molecule EPO, JM4, or sham-treatment with phosphate-buffered saline. Animals treated with JM4 peptide exhibited a large decrease in number of dead neural cells and a marked reduction in lesion size at both 3 and 8 days postinjury. Therapy with JM4 also led to improved functional recovery and we observed a treatment window for JM4 peptide that remained open for at least 9 h postinjury. The full-length EPO molecule was divided into a series of 6 contiguous peptide segments; the JM4-containing segment and the adjoining downstream region contained the bulk of the death attenuating effects seen with intact EPO molecule following TBI. These findings indicate that the JM4 molecule substantially blocks cell death and brain injury following acute brain trauma and, as such, presents an excellent opportunity to explore the therapeutic potential of a small-peptide EPO derivative in the medical treatment of TBI.

  20. Negative Relationship between Erythropoietin Dose and Blood Lead Level in Patients Undergoing Maintenance Hemodialysis

    PubMed Central

    Huang, Wen-Hung; Hsu, Ching-Wei; Weng, Cheng-Hao; Lin-Tan, Dan-Tzu; Yen, Tzung-Hai

    2016-01-01

    The adverse effects of increased blood lead levels have been well discussed. Several antioxidant agents have been reported to offer protection from lead toxicity and to reduce blood lead levels (BLL). Given that erythropoietin (EPO) also has antioxidant properties, the aim of this cross-sectional study was to assess the role of EPO and other clinical variables on BLL in hemodialysis (HD) patients. We recruited 931 maintenance hemodialysis (MHD) patients who had undergone HD for at least 6 months and who had ever received blood lead level (BLL) study. Use of erythropoiesis-stimulating agents followed the The National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF KDOQI) Clinical Practice Guideline. We estimated demographic, hematological, nutritional, inflammatory, biochemical, and dialysis-related data based on this study. In the group with EPO, 7% had high BLL. In the group without EPO, 22% had high BLL. From the stepwise liner regression, urban areas, hemodialysis duration, and clearance of urea (KT/Vurea) were positively associated with log BLL. In contrast, diabetes (DM), and monthly EPO dose were negatively associated with log BLL. This study showed that EPO dose might be negatively associated with blood lead levels in patients on maintenance hemodialysis. PMID:27680289

  1. Erythropoietin protects against diabetes through direct effects on pancreatic β cells

    PubMed Central

    Choi, Diana; Schroer, Stephanie A.; Lu, Shun Yan; Wang, Linyuan; Wu, Xiaohong; Liu, Yunfeng; Zhang, Yi; Gaisano, Herbert Y.; Wagner, Kay-Uwe; Wu, Hong; Retnakaran, Ravi

    2010-01-01

    A common feature among all forms of diabetes mellitus is a functional β-cell mass insufficient to maintain euglycemia; therefore, the promotion of β-cell growth and survival is a fundamental goal for diabetes prevention and treatment. Evidence has suggested that erythropoietin (EPO) exerts cytoprotective effects on nonerythroid cells. However, the influence of EPO on pancreatic β cells and diabetes has not been evaluated to date. In this study, we report that recombinant human EPO treatment can protect against diabetes development in streptozotocin-induced and db/db mouse models of type 1 and type 2 diabetes, respectively. EPO exerts antiapoptotic, proliferative, antiinflammatory, and angiogenic effects within the islets. Using β-cell–specific EPO receptor and JAK2 knockout mice, we show that these effects of EPO result from direct biological effects on β cells and that JAK2 is an essential intracellular mediator. Thus, promotion of EPO signaling in β cells may be a novel therapeutic strategy for diabetes prevention and treatment. PMID:21149549

  2. Safety and angiogenic effects of systemic gene delivery of a modified erythropoietin

    PubMed Central

    de Lucas Cerrillo, Ana; Bond, Wesley S.; Rex, Tonia S.

    2015-01-01

    Erythropoietin (EPO) is critical for red blood cell production and is also an effective neuroprotective agent. However, it may also contribute to pathological angiogenesis. Here we investigate the angiogenic potential of EPO and a mutant form with attenuated erythropoietic activity, EPO-R76E, on primary human retinal microvascular endothelial cells (HRMEC) and in the adult retina. Assays of death, proliferation, and tube-formation were performed on HRMECs exposed to EPO, EPO-R76E, or media alone. Postnatal day 9 wild-type mice were injected intramuscularly with adeno-associated virus vectors expressing either enhanced green fluorescent protein or EpoR76E. At 3 months, levels of EPO-R76E in the eye were quantified, and the health of the retinal vasculature was assessed by fluorescein angiography and isolectin immunolabeling. Immunohistochemistry, histology, and electroretinogram assessments were performed as measures of retinal health. Neither EPO nor EPO-R76E induced proliferation or tube-formation in HRMEC under the conditions used. EPO-R76E decreased HRMEC death in a dose-dependent manner. Long-term systemic gene delivery of EPO-R76E was safe in terms of retinal vasculature, histology, and the electroretinogram in vivo. Our results show that EPO-R76E can block HRMEC death, consistent with its role in erythropoiesis and neuroprotection. In addition, long-term gene delivery of EPO-R76E is safe in the adult retina. PMID:25716531

  3. Sorting of growth hormone-erythropoietin fusion proteins in rat salivary glands

    SciTech Connect

    Samuni, Yuval Zheng Changyu; Cawley, Niamh X.; Cotrim, Ana P.; Loh, Y. Peng; Baum, Bruce J.

    2008-08-15

    Neuroendocrine and exocrine cells secrete proteins in either a constitutive manner or via the regulated secretory pathway (RSP), but the specific sorting mechanisms involved are not fully understood. After gene transfer to rat salivary glands, the transgenic model proteins human growth hormone (hGH) and erythropoietin (hEpo) are secreted primarily into saliva (RSP; exocrine) and serum (constitutive; endocrine), respectively. We hypothesized that fusion of hGH at either the C-terminus or the N-terminus of hEpo would re-direct hEpo from the bloodstream into saliva. We constructed and expressed two fusion proteins, hEpo-hGH and hGH-hEpo, using serotype 5-adenoviral vectors, and delivered them to rat submandibular glands in vivo via retroductal cannulation. Both the hEpo-hGH and hGH-hEpo fusion proteins, but not hEpo alone, were secreted primarily into saliva (p < 0.0001 and p = 0.0083, respectively). These in vivo studies demonstrate for the first time that hGH, in an N- as well as C-terminal position, influences the secretion of a constitutive pathway protein.

  4. Distinct subpopulations of FOXD1 stroma-derived cells regulate renal erythropoietin

    PubMed Central

    Liu, Qingdu; Binns, Thomas C.; Davidoff, Olena; Kapitsinou, Pinelopi P.; Pfaff, Andrew S.; Olauson, Hannes; Fogo, Agnes B.; Fong, Guo-Hua; Gross, Kenneth W.

    2016-01-01

    Renal peritubular interstitial fibroblast-like cells are critical for adult erythropoiesis, as they are the main source of erythropoietin (EPO). Hypoxia-inducible factor 2 (HIF-2) controls EPO synthesis in the kidney and liver and is regulated by prolyl-4-hydroxylase domain (PHD) dioxygenases PHD1, PHD2, and PHD3, which function as cellular oxygen sensors. Renal interstitial cells with EPO-producing capacity are poorly characterized, and the role of the PHD/HIF-2 axis in renal EPO-producing cell (REPC) plasticity is unclear. Here we targeted the PHD/HIF-2/EPO axis in FOXD1 stroma-derived renal interstitial cells and examined the role of individual PHDs in REPC pool size regulation and renal EPO output. Renal interstitial cells with EPO-producing capacity were entirely derived from FOXD1-expressing stroma, and Phd2 inactivation alone induced renal Epo in a limited number of renal interstitial cells. EPO induction was submaximal, as hypoxia or pharmacologic PHD inhibition further increased the REPC fraction among Phd2–/– renal interstitial cells. Moreover, Phd1 and Phd3 were differentially expressed in renal interstitium, and heterozygous deficiency for Phd1 and Phd3 increased REPC numbers in Phd2–/– mice. We propose that FOXD1 lineage renal interstitial cells consist of distinct subpopulations that differ in their responsiveness to Phd2 inactivation and thus regulation of HIF-2 activity and EPO production under hypoxia or conditions of pharmacologic or genetic PHD inactivation. PMID:27088801

  5. Carbamylated erythropoietin protects the kidneys from ischemia-reperfusion injury without stimulating erythropoiesis

    SciTech Connect

    Imamura, Ryoichi; Isaka, Yoshitaka . E-mail: isaka@att.med.osaka-u.ac.jp; Ichimaru, Naotsugu; Takahara, Shiro; Okuyama, Akihiko

    2007-02-16

    Several studies have shown that erythropoietin (EPO) can protect the kidneys from ischemia-reperfusion injury and can raise the hemoglobin (Hb) concentration. Recently, the EPO molecule modified by carbamylation (CEPO) has been identified and was demonstrated to be able to protect several organs without increasing the Hb concentration. We hypothesized that treatment with CEPO would protect the kidneys from tubular apoptosis and inhibit subsequent tubulointerstitial injury without erythropoiesis. The therapeutic effect of CEPO was evaluated using a rat ischemia-reperfusion injury model. Saline-treated kidneys exhibited increased tubular apoptosis with interstitial expression of {alpha}-smooth muscle actin ({alpha}-SMA), while EPO treatment inhibited tubular apoptosis and {alpha}-SMA expression to some extent. On the other hand, CEPO-treated kidneys showed minimal tubular apoptosis with limited expression of {alpha}-SMA. Moreover, CEPO significantly promoted tubular epithelial cell proliferation without erythropoiesis. In conclusion, we identified a new therapeutic approach using CEPO to protect kidneys from ischemia-reperfusion injury.

  6. Erythropoietin (EPO) increases myelin gene expression in CG4 oligodendrocyte cells through the classical EPO receptor.

    PubMed

    Cervellini, Ilaria; Annenkov, Alexander; Brenton, Thomas; Chernajovsky, Yuti; Ghezzi, Pietro; Mengozzi, Manuela

    2013-08-28

    Erythropoietin (EPO) has protective effects in neurodegenerative and neuroinflammatory diseases, including in animal models of multiple sclerosis, where EPO decreases disease severity. EPO also promotes neurogenesis and is protective in models of toxic demyelination. In this study, we asked whether EPO could promote neurorepair by also inducing remyelination. In addition, we investigated whether the effect of EPO could be mediated by the classical erythropoietic EPO receptor (EPOR), since it is still questioned if EPOR is functional in nonhematopoietic cells. Using CG4 cells, a line of rat oligodendrocyte precursor cells, we found that EPO increases the expression of myelin genes (myelin oligodendrocyte glycoprotein [MOG] and myelin basic protein [MBP]). EPO had no effect in wild-type CG4 cells, which do not express EPOR, whereas it increased MOG and MBP expression in cells engineered to overexpress EPOR (CG4-EPOR). This was reflected in a marked increase in MOG protein levels, as detected by Western blot. In these cells, EPO induced by 10-fold the early growth response gene 2 (Egr2), which is required for peripheral myelination. However, Egr2 silencing with a siRNA did not reverse the effect of EPO, indicating that EPO acts through other pathways. In conclusion, EPO induces the expression of myelin genes in oligodendrocytes and this effect requires the presence of EPOR. This study demonstrates that EPOR can mediate neuroreparative effects.

  7. Combining erythropoietin infusion with intramyocardial delivery of bone marrow cells is more effective for cardiac repair.

    PubMed

    Zhang, Dingguo; Zhang, Fumin; Zhang, Yuqing; Gao, Xiang; Li, Chuanfu; Yang, Naiquan; Cao, Kejiang

    2007-02-01

    We postulated that combining erythropoietin (EPO) infusion with bone marrow mesenchymal stem cells (MSC) delivery may give better prognosis in a rat infarcted heart. Acute myocardial infarction (MI) model was developed by coronary artery ligation. Animals were grouped (n=18) to receive intramyocardial injection of 30 microl saline solution without cells (EPO and control groups) or with 3x10(6) MSC from transgenic green fluorescent protein (GFP)+ male mice (MSC and MSC-EPO groups). The animals received either 5000 U/kg body weight EPO (EPO and MSC-EPO groups) or saline solution (MSC and control groups) for 7 days after MI. Cardiac functions were measured by echocardiography and cardiac tissue was harvested for immunohistological studies 3 weeks after surgery. We observed regeneration of MSC in and around the infarcted myocardium in MSC and MSC-EPO groups. Capillary density was markedly enhanced with significantly smaller infarct size and reduced fibrotic area in MSC-EPO group as compared with other three groups. A smaller left ventricular (LV) diastolic dimension and a higher LV fractional shortening were observed in MSC-EPO group than in other three groups. Transplantation of MSC combined with cytokine EPO is superior to either of the monotherapy approach for angiomyogenesis and cardiac function recovery.

  8. Detection of isoelectric profiles of erythropoietin in urine: differentiation of natural and administered recombinant hormones.

    PubMed

    Lasne, Françoise; Martin, Laurent; Crepin, Nathalie; de Ceaurriz, Jacques

    2002-12-15

    Erythropoietin (EPO) is normally present in urine at a low concentration (about 1IU/L, i.e., about 10ng/L) for a total protein concentration of at least 50mg/L. A method to study the isoelectric profile of this hormone from 20-ml urine aliquots without previous purification was developed. This method involves isoelectric focusing of the retentate from ultrafiltered urine. Both the ultrafiltration and the isoelectric focusing required precautionary measures to prevent EPO degradation by the proteases that are present in urine. Because classical immunoblotting gave rise to an unspecific detection of various urinary proteins in the focused retentate, it was essential to use the "double-blotting" process developed to solve this problem. Sufficient sensitivity was achieved using amplified chemiluminiscent detection after the blotting membrane was treated with dithiotreitol. The patterns that were revealed from various urinary samples proved to be highly heterogeneous as they were composed of more than 10 isoforms in a pI range of 3.7-4.7. Clear transformation of the patterns was observed in the case of treatment by the recombinant hormone, suggesting that this method can be regarded an efficient tool for indicating recombinant EPO misuse in sports. It may also open new investigations in the field of physiologic or pathologic exploration.

  9. Desialylation improves the detection of recombinant erythropoietins in urine samples analyzed by SDS-PAGE.

    PubMed

    Desharnais, Philippe; Naud, Jean-François; Ayotte, Christiane

    2013-01-01

    Recombinant erythropoietin (rhEPO) has been misused for over two decades by athletes, mainly but not only in endurance sports. A direct rhEPO detection method in urine by isoelectric focusing (IEF) was introduced in 2000, but the emergence of third-generation erythropoiesis-stimulating agents and so-called biosimilar rhEPOs, together with the sensitivity of human endogenous EPO (huEPO) pattern to enzymatic activities and its modification following short strenuous exercise, prompted the development of a complementary test based on SDS-PAGE analysis. While Mircera and NESP are easily detected with the existing IEF and SDS-PAGE methods, some samples containing both epoetin-α/β and huEPO present profiles that are still difficult to interpret. As doping practices have moved to micro-dosing, these mixed patterns are more frequently observed. We investigated the impact of enzymatic desialylation on the urinary and serum EPO profiles obtained by SDS-PAGE with the aim of improving the separation of the bands in these mixed EPO populations. We observed that the removal with neuraminidase of the sialic acid moieties from the different EPOs studied reduced their apparent molecular weight (MW) and increased the migration distance between huEPO and rhEPO centroids, therefore eliminating the size overlaps between them and improving the detection of rhEPO.

  10. Elevated serum erythropoietin in a patient with polycythaemia vera presenting with Budd-Chiari syndrome

    PubMed Central

    Jones, Catherine; Levy, Yair; Tong, Alex W

    2014-01-01

    Polycythaemia vera (PV) is a clonal disorder of bone marrow stem cells characterised by erythrocytosis. Diagnosis of PV requires exclusion of secondary causes of polycythaemia. It has been held that an elevated erythropoietin (Epo) level strongly indicates secondary erythrocytosis and excludes PV diagnosis, to the extent that the reduced serum Epo level is currently listed as a minor criterion in the WHO classification scheme for PV. However, patients with PV who co-present with Budd-Chiari syndrome have been documented with elevated serum Epo levels. For these patients, identification of the Janus kinase 2 (JAK2) V617F point mutation along with the transient nature of the Epo elevation provides certainty of PV diagnosis, as illustrated by the proband. In this case report, the patient's positive response to cytoreductive therapy (hydroxyurea 500 mg daily) and phlebotomy (750 mL over three phlebotomies) further supports validity of PV diagnosis with elevated Epo. The patient remains on rivaroxaban (Xarelto) for treatment of her portal vein thrombosis. PMID:25452296

  11. Erythropoietin regulates POMC expression via STAT3 and potentiates leptin response.

    PubMed

    Dey, Soumyadeep; Li, Xiaoxia; Teng, Ruifeng; Alnaeeli, Mawadda; Chen, ZhiYong; Rogers, Heather; Noguchi, Constance Tom

    2016-02-01

    The arcuate nucleus of the hypothalamus is essential for metabolic homeostasis and responds to leptin by producing several neuropeptides including proopiomelanocortin (POMC). We previously reported that high-dose erythropoietin (Epo) treatment in mice while increasing hematocrit reduced body weight, fat mass, and food intake and increased energy expenditure. Moreover, we showed that mice with Epo receptor (EpoR) restricted to erythroid cells (ΔEpoRE) became obese and exhibited decreased energy expenditure. Epo/EpoR signaling was found to promote hypothalamus POMC expression independently from leptin. Herein we used WT and ΔEpoRE mice and hypothalamus-derived neural culture system to study the signaling pathways activated by Epo in POMC neurons. We show that Epo stimulation activated STAT3 signaling and upregulated POMC expression in WT neural cultures. ΔEpoRE mice hypothalamus showed reduced POMC levels and lower STAT3 phosphorylation, with and without leptin treatment, compared to in vivo and ex vivo WT controls. Collectively, these data show that Epo regulates hypothalamus POMC expression via STAT3 activation, and provide a previously unrecognized link between Epo and leptin response.

  12. Postnatal Erythropoietin Mitigates Impaired Cerebral Cortical Development Following Subplate Loss from Prenatal Hypoxia-Ischemia.

    PubMed

    Jantzie, Lauren L; Corbett, Christopher J; Firl, Daniel J; Robinson, Shenandoah

    2015-09-01

    Preterm birth impacts brain development and leads to chronic deficits including cognitive delay, behavioral problems, and epilepsy. Premature loss of the subplate, a transient subcortical layer that guides development of the cerebral cortex and axonal refinement, has been implicated in these neurological disorders. Subplate neurons influence postnatal upregulation of the potassium chloride co-transporter KCC2 and maturation of γ-amino-butyric acid A receptor (GABAAR) subunits. We hypothesized that prenatal transient systemic hypoxia-ischemia (TSHI) in Sprague-Dawley rats that mimic brain injury from extreme prematurity in humans would cause premature subplate loss and affect cortical layer IV development. Further, we predicted that the neuroprotective agent erythropoietin (EPO) could attenuate the injury. Prenatal TSHI induced subplate neuronal loss via apoptosis. TSHI impaired cortical layer IV postnatal upregulation of KCC2 and GABAAR subunits, and postnatal EPO treatment mitigated the loss (n ≥ 8). To specifically address how subplate loss affects cortical development, we used in vitro mechanical subplate ablation in slice cultures (n ≥ 3) and found EPO treatment attenuates KCC2 loss. Together, these results show that subplate loss contributes to impaired cerebral development, and EPO treatment diminishes the damage. Limitation of premature subplate loss and the resultant impaired cortical development may minimize cerebral deficits suffered by extremely preterm infants.

  13. Population pharmacodynamic analysis of erythropoiesis in preterm infants for determining the anemia treatment potential of erythropoietin.

    PubMed

    Saleh, Mohammad I; Nalbant, Demet; Widness, John A; Veng-Pedersen, Peter

    2013-05-01

    A population pharmacokinetics/pharmacodynamic (PK/PD) model was developed to describe changes in erythropoiesis as a function of plasma erythropoietin (EPO) concentration over the first 30 days of life in preterm infants who developed severe anemia requiring red blood cell (RBC) transfusion. Several covariates were tested as possible factors influencing the responsiveness to EPO. Discarded blood samples in 27 ventilated preterm infants born at 24-29 wk of gestation were used to construct plasma EPO, hemoglobin (Hb), and RBC concentration-time profiles. The amount of Hb removed for laboratory testing and that transfused throughout the study period were recorded. A population PK/PD model accounting for the dynamic Hb changes experienced by these infants was simultaneously fitted to plasma EPO, Hb, and RBC concentrations. A covariate analysis suggested that the erythropoietic efficacy of EPO is increased for preterm infants at later gestational ages. The PD analysis showed a sevenfold difference in maximum Hb production rate dependent on gestational age and indicated that preterm infants, when stimulated by EPO, have the capacity to produce additional Hb that may result in a decrease in RBC transfusions. The present model has utility in clinical trial simulations investigating the treatment potential of erythropoietic stimulating agents in the treatment of anemia of prematurity.

  14. Erythropoietin protects myocardin-expressing cardiac stem cells against cytotoxicity of tumor necrosis factor-{alpha}

    SciTech Connect

    Madonna, Rosalinda; Shelat, Harnath; Xue, Qun; Willerson, James T.; De Caterina, Raffaele; Geng, Yong-Jian

    2009-10-15

    Cardiac stem cells are vulnerable to inflammation caused by infarction or ischemic injury. The growth factor, erythropoietin (Epo), ameliorates the inflammatory response of the myocardium to ischemic injury. This study was designed to assess the role of Epo in regulation of expression and activation of the cell death-associated intracellular signaling components in cardiac myoblasts stimulated with the proinflammatory cytokine tumor necrosis factor (TNF)-{alpha}. Cardiac myoblasts isolated from canine embryonic hearts characterized by expression of myocardin A, a promyogenic transcription factor for cardiovascular muscle development were pretreated with Epo and then exposed to TNF-{alpha}. Compared to untreated cells, the Epo-treated cardiac myoblasts exhibited better morphology and viability. Immunoblotting revealed lower levels of active caspase-3 and reductions in iNOS expression and NO production in Epo-treated cells. Furthermore, Epo pretreatment reduced nuclear translocation of NF-{kappa}B and inhibited phosphorylation of inhibitor of kappa B (I{kappa}B) in TNF-{alpha}-stimulated cardiac myoblasts. Thus, Epo protects cardiac myocyte progenitors or myoblasts against the cytotoxic effects of TNF-{alpha} by inhibiting NF-{kappa}B-mediated iNOS expression and NO production and by preventing caspase-3 activation.

  15. Erythropoietin Promotes Bone Formation through EphrinB2/EphB4 Signaling

    PubMed Central

    Li, C.; Shi, C.; Kim, J.; Chen, Y.; Ni, S.; Jiang, L.; Zheng, C.; Li, D.; Hou, J.; Sun, H.

    2015-01-01

    Recent studies have demonstrated that erythropoietin (EPO) has extensive nonhematopoietic biological functions. However, little is known about how EPO regulates bone formation, although several studies suggested that EPO can affect bone homeostasis. In this study, we investigated the effects of EPO on the communication between osteoclasts and osteoblasts through the ephrinB2/EphB4 signaling pathway. We found that EPO slightly promotes osteoblastic differentiation with the increased expression of EphB4 in ST2 cells. However, EPO increased the expression of Nfatc1 and ephrinB2 but decreased the expression of Mmp9 in RAW264.7 cells, resulting in an increase of ephrinB2-expressing osteoclasts and a decrease in resorption activity. The stimulation of ephrinB2/EphB4 signaling via ephrinB2-Fc significantly promoted EPO-mediated osteoblastic differentiation in ST2 cells. EphB4 knockdown through EphB4 shRNA inhibited EPO-mediated osteoblastic phenotypes. Furthermore, in vivo assays clearly demonstrated that EPO efficiently induces new bone formation in the alveolar bone regeneration model. Taken together, these results suggest that ephrinB2/EphB4 signaling may play an important role in EPO-mediated bone formation. PMID:25586589

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

    PubMed Central

    Wiese, Lothar; Hempel, Casper; Penkowa, Milena; Kirkby, Nikolai; Kurtzhals, Jørgen AL

    2008-01-01

    Background Cerebral malaria (CM) is an acute encephalopathy with increased pro-inflammatory cytokines, sequestration of parasitized erythrocytes and localized ischaemia. In children CM induces cognitive impairment in about 10% of the survivors. Erythropoietin (Epo) has – besides of its well known haematopoietic properties – significant anti-inflammatory, antioxidant and anti-apoptotic effects in various brain disorders. The neurobiological responses to exogenously injected Epo during murine CM were examined. Methods Female C57BL/6j mice (4–6 weeks), infected with Plasmodium berghei ANKA, were treated with recombinant human Epo (rhEpo; 50–5000 U/kg/OD, i.p.) at different time points. The effect on survival was measured. Brain pathology was investigated by TUNEL (Terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP)-digoxigenin nick end labelling), as a marker of apoptosis. Gene expression in brain tissue was measured by real time PCR. Results Treatment with rhEpo increased survival in mice with CM in a dose- and time-dependent manner and reduced apoptotic cell death of neurons as well as the expression of pro-inflammatory cytokines in the brain. This neuroprotective effect appeared to be independent of the haematopoietic effect. Conclusion These results and its excellent safety profile in humans makes rhEpo a potential candidate for adjunct treatment of CM. PMID:18179698

  17. An alternative to animal testing in the quality control of erythropoietin.

    PubMed

    Zimmermann, H; Gerhard, D; Hothorn, L A; Dingermann, T

    2011-06-01

    A physico-chemical method has been developed as an alternative to the current bioassay in normocythaemic mice for estimating the biological activity of erythropoietin batches. Capillary zone electrophoresis was used for quantification of the isoforms and their substructures were further elucidated by N-glycan mapping techniques. The analytical study was carried out on a total of 40 batches of epoetin beta which were selected to cover an adequate range of precisely established potency values. The relationship between the biological and chemical parameters was evaluated statistically in order to identify suitable covariates for the prediction of the biological activity. Out of several alternatives, a prediction model which is based on the percentages of isoforms per batch and the degree of sialidation was selected and tested. This model is comparable in terms of accuracy to the established in vivo bioassay, but is far superior in terms of precision. Further advantages of the method are improved animal welfare and savings in time and effort. The question whether the prediction model already meets the requirements for replacing the bioassay according to the ICH guideline Q6B is discussed.

  18. Postnatal Erythropoietin Mitigates Impaired Cerebral Cortical Development Following Subplate Loss from Prenatal Hypoxia–Ischemia

    PubMed Central

    Jantzie, Lauren L.; Corbett, Christopher J.; Firl, Daniel J.; Robinson, Shenandoah

    2015-01-01

    Preterm birth impacts brain development and leads to chronic deficits including cognitive delay, behavioral problems, and epilepsy. Premature loss of the subplate, a transient subcortical layer that guides development of the cerebral cortex and axonal refinement, has been implicated in these neurological disorders. Subplate neurons influence postnatal upregulation of the potassium chloride co-transporter KCC2 and maturation of γ-amino-butyric acid A receptor (GABAAR) subunits. We hypothesized that prenatal transient systemic hypoxia–ischemia (TSHI) in Sprague–Dawley rats that mimic brain injury from extreme prematurity in humans would cause premature subplate loss and affect cortical layer IV development. Further, we predicted that the neuroprotective agent erythropoietin (EPO) could attenuate the injury. Prenatal TSHI induced subplate neuronal loss via apoptosis. TSHI impaired cortical layer IV postnatal upregulation of KCC2 and GABAAR subunits, and postnatal EPO treatment mitigated the loss (n ≥ 8). To specifically address how subplate loss affects cortical development, we used in vitro mechanical subplate ablation in slice cultures (n ≥ 3) and found EPO treatment attenuates KCC2 loss. Together, these results show that subplate loss contributes to impaired cerebral development, and EPO treatment diminishes the damage. Limitation of premature subplate loss and the resultant impaired cortical development may minimize cerebral deficits suffered by extremely preterm infants. PMID:24722771

  19. [Clinical use of serum erythropoietin determination by the recombigen EPO RIA kit].

    PubMed

    Masaki, Y; Oka, N; Furuya, H; Ohguni, S; Takagi, C; Sato, T; Notsu, K; Kato, Y

    1992-06-01

    Serum erythropoietin (EPO) levels were determined by the recombigen EPO RIA kit (DPC) in normal subjects and patients with renal dysfunction, diabetes mellitus, hypothyroidism and a variety of hematological disorders. Mean (+/- SD) serum EPO levels were 18.6 +/- 5.6 mU/ml in 180 normal subjects and no sex difference was obtained. Serum EPO levels in older subjects were slightly greater than those in younger subjects. There was a negative correlation between serum EPO levels and Ht values in anemic patients with normal renal function, whereas serum EPO levels were within the normal range in anemic patients with renal disorders, suggesting that serum EPO levels were relatively low in patients with chronic renal failure. Serum EPO levels were rather increased in patients with diabetes mellitus and hypothyroidism. High serum EPO levels were obtained in patients with a variety of hematological disorders such as acute leukemia, multiple myeloma, myelodysplasia syndrome, aplastic anemia and pure red cell aplasia. In a patient with pure red cell aplasia treated with glucocorticoids, serum EPO levels were lowered before anemia was recovered and reticulocytes were increased. These findings indicate that measurement of serum EPO levels are useful for not only differential diagnosis of anemia but also clinical evaluation of the treatment.

  20. Erythropoietin Exacerbates Inflammation and Increases the Mortality of Histoplasma capsulatum-Infected Mice

    PubMed Central

    Locachevic, Gisele Aparecida; Pereira, Priscilla Aparecida Tartari; Secatto, Adriana; Fontanari, Caroline; Galvão, Alyne Fávero; Prado, Morgana Kelly Borges; Zoccal, Karina Furlani; Petta, Tânia; Moraes, Luiz Alberto Beraldo; Ramos, Simone Gusmão; de Castro, Fabíola Attie; Sorgi, Carlos Artério; Faccioli, Lúcia Helena

    2015-01-01

    Erythropoietin (EPO) is a key hormone involved in red blood cell formation, but its effects on nonerythroid cells, such as macrophages, have not been described. Macrophages are key cells in controlling histoplasmosis, a fungal infection caused by Histoplasma capsulatum (Hc). Considering that little is known about EPO's role during fungal infections and its capacity to activate macrophages, in this study we investigated the impact of EPO pretreatment on the alveolar immune response during Hc infection. The consequence of EPO pretreatment on fungal infection was determined by evaluating animal survival, fungal burden, activation of bronchoalveolar macrophages, inflammatory mediator release, and lung inflammation. Pretreatment with EPO diminished mononuclear cell numbers, increased the recruitment of F4/80+/CD80+ and F4/80+/CD86+ cells to the bronchoalveolar space, induced higher production of IFN-γ, IL-6, MIP-1α, MCP-1, and LTB4, reduced PGE2 concentration, and did not affect fungal burden. As a consequence, we observed an increase in lung inflammation with extensive tissue damage that might account for augmented mouse mortality after infection. Our results demonstrate for the first time that EPO treatment has a deleterious impact on lung immune responses during fungal infection. PMID:26538835

  1. Poly-γ-glutamic acid enhances the quality of recombant erythropoietin produced by CHO cells.

    PubMed

    Kim, Tae Gon; Cho, Young Chol; Chun, Bok-Hwan; Park, Sung Hyo; Lee, Hoi-Seon; Chung, Namhyun

    2014-03-04

    The effect of poly-γ-glutamic acid (γPGA), which is produced by Bacillus sp., on the production of recombinant erythropoietin (rEPO) by Chinese hamster ovary (CHO) cells in suspension culture was evaluated. The growth, viability, and productivity of recombinant CHO cells were investigated in a chemically defined medium with 50 and 500 kD γPGAs at 0.075% or with Pluronic F68. Cell growth with the two γPGAs was lower than that with Pluronic F68 but significantly higher than that without any additive (control). The effect of additives on rEPO productivity was 50 kDa γPGA > 500 kDa γPGA > Pluronic F68 > control. Using EPO-dependent F-36E cells, we found that the effect of additives on rEPO quality was 500 kDa γPGA > 50 kDa γPGA > control > Pluronic F68. γPGA has an enhancement effect on the quality of rEPO produced by CHO cells.

  2. In silico design and analysis of a new hyperglycosylated analog of erythropoietin to improve drug efficacy

    PubMed Central

    Kianmehr, Anvarsadat; Mohammadi, Hamid Shahbaz; Shokrgozar, Mohammad Ali; Omidinia, Eskandar

    2015-01-01

    Background: The enhancement of glycosylation by applying glycoengineering approaches has become widely used to boost properties for protein therapeutics. The objective of this work was to engineer a new hyperglycosylated analog of erythropoietin (EPO) with appropriately targeted N-linked carbohydrates through bioinformatics tools. Materials and Methods: The EPO protein sequence was retrieved from NCBI protein sequence database. Prediction of N-glycosylation sites for the target protein was done using the prediction server, NetNGlyc. The three-dimensional model of glycoengineered EPO (named as kypoetin) was constructed using the homology modeling program. Ramchandran plot obtained from PROCHECK server was used to check stereochemical property. Meanwhile, 3D model of kypoetin with attached N-carbohydrates was built up using the GlyProt server. Results: In the new modified analog, three additional N-glycosylation sites at amino-acid positions 30, 34 and 86 were inserted. Ramchandran plot analysis showed 81.6% of the residues in the most favored region, 15.6% in the additional allowed, 1.4% in the generously allowed regions and 1.4% in the disallowed region. 3D structural modeling showed that attached carbohydrates were on the proper spatial position. The whole solvent accessible surface areas of kypoetin (15132.69) were higher than EPO (9938.62). Conclusions: Totally, various model evaluation methods indicated that the glycoengineered version of EPO had considerably good geometry and acceptable profiles for clinical studies and could be considered as the effective drug. PMID:26322290

  3. Erythropoietin Slows Photoreceptor Cell Death in a Mouse Model of Autosomal Dominant Retinitis Pigmentosa

    PubMed Central

    Kasmala, Lorraine; Bond, Wesley S.; de Lucas Cerrillo, Ana M.; Wynn, Kristi; Lewin, Alfred S.

    2016-01-01

    Purpose To test the efficacy of systemic gene delivery of a mutant form of erythropoietin (EPO-R76E) that has attenuated erythropoietic activity, in a mouse model of autosomal dominant retinitis pigmentosa. Methods Ten-day old mice carrying one copy of human rhodopsin with the P23H mutation and both copies of wild-type mouse rhodopsin (hP23H RHO+/-,mRHO+/+) were injected into the quadriceps with recombinant adeno-associated virus (rAAV) carrying either enhanced green fluorescent protein (eGFP) or EpoR76E. Visual function (electroretinogram) and retina structure (optical coherence tomography, histology, and immunohistochemistry) were assessed at 7 and 12 months of age. Results The outer nuclear layer thickness decreased over time at a slower rate in rAAV.EpoR76E treated as compared to the rAAV.eGFP injected mice. There was a statistically significant preservation of the electroretinogram at 7, but not 12 months of age. Conclusions Systemic EPO-R76E slows death of the photoreceptors and vision loss in hP23H RHO+/-,mRHO+/+ mice. Treatment with EPO-R76E may widen the therapeutic window for retinal degeneration patients by increasing the number of viable cells. Future studies might investigate if co-treatment with EPO-R76E and gene replacement therapy is more effective than gene replacement therapy alone. PMID:27299810

  4. Antidepressant-Like Effects of Erythropoietin: A Focus on Behavioural and Hippocampal Processes

    PubMed Central

    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. PMID:24019878

  5. Calmodulin physically interacts with the erythropoietin receptor and enhances Jak2-mediated signaling

    SciTech Connect

    Kakihana, Kazuhiko; Yamamoto, Masahide; Iiyama, Mitsuko; Miura, Osamu . E-mail: miura.hema@tmd.ac.jp

    2005-09-23

    Stimulation of the erythropoietin receptor (EpoR) induces a transient increase in intracellular Ca{sup 2+} level as well as activation of the Jak2 tyrosine kinase to stimulate various downstream signaling pathways. Here, we demonstrate that the universal Ca{sup 2+} receptor calmodulin (CaM) binds EpoR in a Ca{sup 2+}-dependent manner in vitro. Binding studies using various EpoR mutants in hematopoietic cells showed that CaM binds the membrane-proximal 65-amino-acid cytoplasmic region (amino acids 258-312) of EpoR that is critical for activation of Jak2-mediated EpoR signaling. Structurally unrelated CaM antagonists, W-13 and CMZ, inhibited activation of Jak2-mediated EpoR signaling pathways, whereas W-12, a W-13 analog, did not show any significant inhibitory effect. Moreover, overexpression of CaM augmented Epo-induced tyrosine phosphorylation of the EpoR. W-13, but not W-12, also inhibited Epo-induced proliferation and survival. Together, these results indicate that CaM binds to the membrane-proximal EpoR cytoplasmic region and plays an essential role in activation of Jak2-mediated EpoR signaling.

  6. Construction and genetic selection of small transmembrane proteins that activate the human erythropoietin receptor.

    PubMed

    Cammett, Tobin J; Jun, Susan J; Cohen, Emily B; Barrera, Francisco N; Engelman, Donald M; Dimaio, Daniel

    2010-02-23

    This work describes a genetic approach to isolate small, artificial transmembrane (TM) proteins with biological activity. The bovine papillomavirus E5 protein is a dimeric, 44-amino acid TM protein that transforms cells by specifically binding and activating the platelet-derived growth factor beta receptor (PDGFbetaR). We used the E5 protein as a scaffold to construct a retrovirus library expressing approximately 500,000 unique 44-amino acid proteins with randomized TM domains. We screened this library to select small, dimeric TM proteins that were structurally unrelated to erythropoietin (EPO), but specifically activated the human EPO receptor (hEPOR). These proteins did not activate the murine EPOR or the PDGFbetaR. Genetic studies with one of these activators suggested that it interacted with the TM domain of the hEPOR. Furthermore, this TM activator supported erythroid differentiation of primary human hematopoietic progenitor cells in vitro in the absence of EPO. Thus, we have changed the specificity of a protein so that it no longer recognizes its natural target but, instead, modulates an entirely different protein. This represents a novel strategy to isolate small artificial proteins that affect diverse membrane proteins. We suggest the word "traptamer" for these transmembrane aptamers.

  7. Erythropoietin Pretreatment of Transplanted Endothelial Colony-Forming Cells Enhances Recovery in a Cerebral Ischemia Model by Increasing Their Homing Ability: A SPECT/CT Study.

    PubMed

    Garrigue, Philippe; Hache, Guillaume; Bennis, Youssef; Brige, Pauline; Stalin, Jimmy; Pellegrini, Lionel; Velly, Lionel; Orlandi, Francesca; Castaldi, Elena; Dignat-George, Françoise; Sabatier, Florence; Guillet, Benjamin

    2016-11-01

    Endothelial colony-forming cells (ECFCs) are promising candidates for cell therapy of ischemic diseases, as less than 10% of patients with an ischemic stroke are eligible for thrombolysis. We previously reported that erythropoietin priming of ECFCs increased their in vitro and in vivo angiogenic properties in mice with hindlimb ischemia. The present study used SPECT/CT to evaluate whether priming of ECFCs with erythropoietin could enhance their homing to the ischemic site after transient middle cerebral artery occlusion (MCAO) followed by reperfusion in rats and potentiate their protective or regenerative effect on blood-brain barrier (BBB) disruption, cerebral apoptosis, and cerebral blood flow (CBF).

  8. Veterans Health Administration

    MedlinePlus

    ... code here VA » Veterans Health Administration Veterans Health Administration Marine Continues to Serve by Serving Veterans David ... Read more » VA Medical Centers The Veterans Health Administration is home to the United States’ largest integrated ...

  9. Massive bone marrow involvement in an end stage renal failure case with erythropoietin-resistant anemia and primary hyperoxaluria.

    PubMed

    Taşlı, Funda; Özkök, Güliz; Ok, Ebru Sevinç; Soyer, Nur; Mollamehmetoğlu, Hülya; Vardar, Enver

    2013-09-01

    Primary hyperoxaluria is a rare autosomal recessive disorder. Type 1 PH is the most common form and develops due to a defect in a liver specific enzyme the alanine aminotransferase enzyme. As a result of the enzyme deficiency, there is an overproduction of oxalate and excessive urinary excretion. Recurrent urolithiasis and nephrocalcinosis are the most important findings of the disorder and often at the beginning end-stage renal disease develops. This report presents a case backed up by literature of a patient with end stage renal failure and erythropoietin-resistant anaemia whose bone marrow biopsy showed crystal deposition which received delayed diagnosis of oxalosis.

  10. Development and characterization of a human antibody reference panel against erythropoietin suitable for the standardization of ESA immunogenicity testing.

    PubMed

    Mytych, Daniel T; Barger, Troy E; King, Chadwick; Grauer, Stephanie; Haldankar, Raj; Hsu, Eric; Wu, Michelle Min; Shiwalkar, Mukta; Sanchez, Sergio; Kuck, Andrew; Civoli, Francesca; Sun, Jilin; Swanson, Steven J

    2012-08-31

    Recombinant human erythropoietin (EPO) has been used therapeutically for more than two decades in the treatment of anemia. Although EPO is generally well tolerated, in rare cases, patients have developed anti-EPO antibodies that can negatively impact safety and efficacy. Therefore, the detection of antibodies against EPO is a regulatory requirement during clinical development and post-approval. Although it is a rare phenomenon, antibody-mediated pure red cell aplasia (PRCA) is a serious complication than can result from antibodies that develop and neutralize EPO as well as endogenous erythropoietin. Currently, there are no universally accepted analytical methods to detect the full repertoire of binding and neutralizing anti-EPO antibodies. A number of different methods that differ in terms of antibodies detected and assay sensitivities are used by different manufacturers. There is also a lack of antibody reference reagents, and therefore no consistent basis for detecting and measuring anti-EPO antibodies. Reference reagents, with established ranges, are essential to monitor the safety and efficacy of all erythropoiesis-stimulating agents (ESAs) structurally related to human erythropoietin. This is the first report of the development and characterization of a panel of fully human antibodies against EPO suitable as reference reagents. The characteristics of antibodies within the panel were selected based on the prevalence of non-neutralizing IgG and IgM antibodies in non-PRCA patients and neutralizing IgG antibodies, including IgG1 and IgG4, in antibody-mediated PRCA subjects. The reference panel includes antibodies of high- and low-affinity with binding specificity to neutralizing and non-neutralizing erythropoietin epitopes. The subclass of human antibodies in this reference panel includes an IgG1, IgG2, and IgG4, as well as an IgM isotype. This antibody panel could help select appropriate immunogenicity assays, guide validation, and monitor assay performance

  11. Is it time for a paradigm shift? Is erythropoietin deficiency still the main cause of renal anaemia?

    PubMed

    Eschbach, Joseph W; Varma, Ashok; Stivelman, John C

    2002-01-01

    An increasing number of reports documenting resistance to human recombinant erythropoietin (rHuEPO) therapy are challenging the concept that erythropoietin deficiency is the main cause of the anaemia of chronic kidney disease (CKD). In an attempt to establish whether other factors play a more predominant role in the anaemia of CKD, 988 patients receiving dialysis were assessed for a wide range of variables. Data were collected on haematocrit (Hct) levels, rHuEPO dose, dry weight, serum ferritin, transferrin saturation, serum albumin, serum aluminium, serum parathyroid hormone intact, eKt/V for urea, gender, dose of i.v. iron administered, time in hospital, and use of i.v. vancomycin. Hyporesponsiveness to rHuEPO was defined as patients requiring >500 IU/kg/week or failing to achieve Hct levels of >30%. Ninety-two (9.2%) of the 988 patients met the above criteria for hyporesponsiveness to rHuEPO. In 21 of these patients, Hct concentrations remained <30% at 6-month follow-up. There were known haematological causes of refractoriness to rHuEPO in nine of these patients. During extended follow-up, probable causes of hyporesponsiveness were discovered in all but two of the remaining 13 patients. Of 62 dialysis patients who received rHuEPO at doses >500 IU/kg/week, 45 (73%) had Hct concentrations of 33-42%. These patients were responding to the higher doses of rHuEPO with no obvious adverse effects. Lower values of serum ferritin, transferrin saturation, and eKt/V, or higher levels of parathyroid hormone or serum aluminium were not associated with higher rHuEPO dose requirements. These results suggest that erythropoietin deficiency is still the main cause of the anaemia of CKD. Erythropoietin replacement therapy can correct the anaemia in almost all iron replete patients providing enough hormone is given, functional iron deficiency is avoided, aluminium levels and parathyroid toxicities are controlled and that no de novo haematological condition that affects

  12. Role of recombinant human erythropoietin loading chitosan-tripolyphosphate nanoparticles in busulfan-induced genotoxicity: Analysis of DNA fragmentation via comet assay in cultured HepG2 cells.

    PubMed

    Ghassemi-Barghi, Nasrin; Varshosaz, Jaleh; Etebari, Mahmoud; Jafarian Dehkordi, Abbas

    2016-10-01

    Busulfan is one of the most effective chemotherapeutic agents used for the treatment of chronic myeloid leukemia. Busulfan is involved in secondary malignancy due to its genotoxic potential in normal tissues. As an alkylating agent busulfan can cause DNA damage by cross-linking DNAs and DNA and proteins, induces senescence in normal cells via transient depletion of intracellular glutathione (GSH) and subsequently by a continuous increase in reactive oxygen species (ROS) production. Erythropoietin, a glycoprotein widely used against drug induced anemia in cancerous patients and regulates hematopoiesis, has been shown to exert an important cyto-protective effect in many tissues. Recombinant human erythropoietin has been demonstrated to directly limit cell injury and ROS generation during oxidative stress. Furthermore, rhEPO decreased levels of pro-apoptotic factor (Bax) and also increased expression of the anti-apoptotic factor Bcl2. According to EPO's short half-life and requirements for the frequently administration, finding the new strategies to attenuate its side effects is important. The aim of this study was to explore whether rhEPO loading chitosan-tripolyphosphate nanoparticles protects against busulfan-induced genotoxicity in HepG2 cells. For this purpose cells were incubated with busulfan alone, regular rhEPO alone and regular rhEPO and CS-TPP-EPO nanoparticles along with busulfan in pre and co-treatment condition. Our results showed that busulfan induced a noticeable genotoxic effects in HepG2 cells (p<0.0001). Both regular rhEPO and CS-TPP-EPO nanoparticles reduced the effects of busulfan significantly (p<0.0001) by reduction of the level of DNA damage via blocking ROS generation, and enhancement intracellular glutathione levels. CS-TPP-EPO nanoparticles were more effective than regular rhEPO in both pre and co-treatment conditions. In conclusion, our results show that administration of rhEPO and CS-TPP-EPO nanoparticles especially in the pre

  13. Enhancement of ventricular-subventricular zone-derived neurogenesis and oligodendrogenesis by erythropoietin and its derivatives.

    PubMed

    Kaneko, Naoko; Kako, Eisuke; Sawamoto, Kazunobu

    2013-11-27

    In the postnatal mammalian brain, stem cells in the ventricular-subventricular zone (V-SVZ) continuously generate neuronal and glial cells throughout life. Genetic labeling of cells of specific lineages have demonstrated that the V-SVZ is an important source of the neuroblasts and/or oligodendrocyte progenitor cells (OPCs) that migrate toward injured brain areas in response to several types of insult, including ischemia and demyelinating diseases. However, this spontaneous regeneration is insufficient for complete structural and functional restoration of the injured brain, so interventions to enhance these processes are sought for clinical applications. Erythropoietin (EPO), a clinically applied erythropoietic factor, is reported to have cytoprotective effects in various kinds of insult in the central nervous system. Moreover, recent studies suggest that EPO promotes the V-SVZ-derived neurogenesis and oligodendrogenesis. EPO increases the proliferation of progenitors in the V-SVZ and/or the migration and differentiation of their progenies in and around injured areas, depending on the dosage, timing, and duration of treatment, as well as the type of animal model used. On the other hand, EPO has undesirable side effects, including thrombotic complications. We recently demonstrated that a 2-week treatment with the EPO derivative asialo-EPO promotes the differentiation of V-SVZ-derived OPCs into myelin-forming mature oligodendrocytes in the injured white matter of neonatal mice without causing erythropoiesis. Here we present an overview of the multifaceted effects of EPO and its derivatives in the V-SVZ and discuss the possible applications of these molecules in regenerative medicine.

  14. Erythropoietin improves functional and histological recovery of traumatized skeletal muscle tissue.

    PubMed

    Rotter, Robert; Menshykova, Marija; Winkler, Tobias; Matziolis, Georg; Stratos, Ioannis; Schoen, Matthias; Bittorf, Thomas; Mittlmeier, Thomas; Vollmar, Brigitte

    2008-12-01

    Apart from its hematopoietic effect, erythropoietin (EPO) is known as pleiotropic cytokine with anti-inflammatory and anti-apoptotic properties. Here, we evaluated for the first time the EPO-dependent regeneration capacity in an in vivo rat model of skeletal muscle trauma. A myoblast cell line was used to study the effect of EPO on serum deprivation-induced cell apoptosis in vitro. A crush injury was performed to the left soleus muscle in 80 rats treated with either EPO or saline. Muscle recovery was assessed by analysis of contraction capacities. Intravital microscopy, BrdU/laminin double immunohistochemistry and cleaved caspase-3 immunohistochemistry of muscle tissue on days 1, 7, 14, and 42 posttrauma served for assessment of local microcirculation, tissue integrity, and cell proliferation. Serum deprivation-induced myoblast apoptosis of 23.9 +/- 1.5% was reduced by EPO to 17.2 +/- 0.8%. Contraction force analysis in the EPO-treated animals revealed significantly improved muscle strength with 10-20% higher values of twitch and tetanic forces over the 42-day observation period. EPO-treated muscle tissue displayed improved functional capillary density as well as reduced leukocytic response and consecutively macromolecular leakage over day 14. Concomitantly, muscle histology showed significantly increased numbers of BrdU-positive satellite cells and interstitial cells as well as slightly lower counts of cleaved caspase-3-positive interstitial cells. EPO results in faster and better regeneration of skeletal muscle tissue after severe trauma and goes along with improved microcirculation. Thus, EPO, a compound established as clinically safe, may represent a promising therapeutic option to optimize the posttraumatic course of muscle tissue healing.

  15. Neural stem cell transplantation combined with erythropoietin for the treatment of spinal cord injury in rats.

    PubMed

    Zhao, Yan; Zuo, Yuan; Jiang, Jianming; Yan, Huibo; Wang, Xiliang; Huo, Hunjun; Xiao, Yulong

    2016-10-01

    Spinal cord injury (SCI) comprises nerve and motor function disorders that may be caused by a variety of damaging factors and is challenging to treat. The aim of the present study was to investigate the regenerative effects of neural stem cell (NSC) transplantation combined with intraperitoneal injection of erythropoietin (EPO) on cross-sectional SCI in rats. A model of SCI was induced in 40 adult Wistar rats via the complete transection of the 10th thoracic vertebra (T10). The rats were allocated at random into 4 groups: Control, NSC, EPO and NSC + EPO groups (n=10 per group). Morphological alterations associated with axonal regeneration were detected using neurofilament (NF)-200 immunohistochemistry and immunofluorescence staining after 8 weeks. Basso, Beattie and Bresnahan (BBB) scoring was used to evaluate the recovery of hindlimb function. A total of 5 rats died following surgery, including 2 control rats and 1 rat each in the EPO, NSC and NSC + EPO groups. NSCs labeled with bromodeoxyuridine were observed to have survived and migrated in the spinal cord tissue after 8 weeks. Significant histomorphological differences were observed in the NSC and NSC + EPO groups compared with the EPO and control groups. Furthermore, the rats of the NSC + EPO group exhibited significantly enhanced axonal regeneration in the SCI area compared with the NSC group rats. The rats of the NSC and NSC + EPO groups exhibited significantly improved BBB scores compared with the EPO and control group rats at 7 days after treatment (P<0.05). In addition, the BBB scores of the NSC + EPO group were significantly improved compared with those of the three other groups at 7 days after surgery (P<0.05). Therefore, the results of the present study suggest that NSC transplantation combined with intraperitoneal injection of EPO may benefit the survival and regeneration of injured axons, and accelerate the repair of injured spinal cord tissue, thus facilitating the functional recovery of hindlimb

  16. Erythropoietin (EPO): EPO-receptor signaling improves early endochondral ossification and mechanical strength in fracture healing.

    PubMed

    Holstein, Joerg H; Menger, Michael D; Scheuer, Claudia; Meier, Christoph; Culemann, Ulf; Wirbel, Rainer J; Garcia, Patric; Pohlemann, Tim

    2007-02-13

    Beyond its role in the regulation of red blood cell proliferation, the glycoprotein erythropoietin (EPO) has been shown to promote cell regeneration and angiogenesis in a variety of different tissues. In addition, EPO has been indicated to share significant functional and structural homologies with the vascular endothelial growth factor (VEGF), a cytokine essential in the process of fracture healing. However, there is complete lack of information on the action of EPO in bone repair and fracture healing. Therefore, we investigated the effect of EPO treatment on bone healing in a murine closed femur fracture model using radiological, histomorphometric, immunohistochemical, biomechanical and protein biochemical analysis. Thirty-six SKH1-hr mice were treated with daily i.p. injections of 5000 U/kg EPO from day 1 before fracture until day 4 after fracture. Controls received equivalent amounts of the vehicle. After 2 weeks of fracture healing, we could demonstrate expression of the EPO-receptor (EPOR) in terminally differentiating chondrocytes within the callus. At this time point EPO-treated animals showed a higher torsional stiffness (biomechanical analysis: 39.6+/-19.4% of the contralateral unfractured femur) and an increased callus density (X-ray analysis (callus density/spongiosa density): 110.5+/-7.1%) when compared to vehicle-treated controls (14.3+/-8.2% and 105.9+/-6.6%; p<0.05). Accordingly, the histomorphometric examination revealed an increased fraction of mineralized bone and osteoid (33.0+/-3.0% versus 28.5+/-3.6%; p<0.05). Of interest, this early effect of the initial 6-day EPO treatment had vanished at 5 weeks after fracture. We conclude that EPO-EPOR signaling is involved in the process of early endochondral ossification, enhancing the transition of soft callus to hard callus.

  17. Neural stem cell transplantation combined with erythropoietin for the treatment of spinal cord injury in rats

    PubMed Central

    Zhao, Yan; Zuo, Yuan; Jiang, Jianming; Yan, Huibo; Wang, Xiliang; Huo, Hunjun; Xiao, Yulong

    2016-01-01

    Spinal cord injury (SCI) comprises nerve and motor function disorders that may be caused by a variety of damaging factors and is challenging to treat. The aim of the present study was to investigate the regenerative effects of neural stem cell (NSC) transplantation combined with intraperitoneal injection of erythropoietin (EPO) on cross-sectional SCI in rats. A model of SCI was induced in 40 adult Wistar rats via the complete transection of the 10th thoracic vertebra (T10). The rats were allocated at random into 4 groups: Control, NSC, EPO and NSC + EPO groups (n=10 per group). Morphological alterations associated with axonal regeneration were detected using neurofilament (NF)-200 immunohistochemistry and immunofluorescence staining after 8 weeks. Basso, Beattie and Bresnahan (BBB) scoring was used to evaluate the recovery of hindlimb function. A total of 5 rats died following surgery, including 2 control rats and 1 rat each in the EPO, NSC and NSC + EPO groups. NSCs labeled with bromodeoxyuridine were observed to have survived and migrated in the spinal cord tissue after 8 weeks. Significant histomorphological differences were observed in the NSC and NSC + EPO groups compared with the EPO and control groups. Furthermore, the rats of the NSC + EPO group exhibited significantly enhanced axonal regeneration in the SCI area compared with the NSC group rats. The rats of the NSC and NSC + EPO groups exhibited significantly improved BBB scores compared with the EPO and control group rats at 7 days after treatment (P<0.05). In addition, the BBB scores of the NSC + EPO group were significantly improved compared with those of the three other groups at 7 days after surgery (P<0.05). Therefore, the results of the present study suggest that NSC transplantation combined with intraperitoneal injection of EPO may benefit the survival and regeneration of injured axons, and accelerate the repair of injured spinal cord tissue, thus facilitating the functional recovery of hindlimb

  18. Erythropoietin enhances nerve repair in anti-ganglioside antibody-mediated models of immune neuropathy.

    PubMed

    Zhang, Gang; Lehmann, Helmar C; Bogdanova, Nataliia; Gao, Tong; Zhang, Jiangyang; Sheikh, Kazim A

    2011-01-01

    Guillain-Barré syndrome (GBS) is a monophasic immune neuropathic disorder in which a significant proportion of patients have incomplete recovery. The patients with incomplete recovery almost always have some degree of failure of axon regeneration and target reinnervation. Anti-ganglioside antibodies (Abs) are the most commonly recognized autoimmune markers in all forms of GBS and specific Abs are associated with the slow/poor recovery. We recently demonstrated that specific anti-ganglioside Abs inhibit axonal regeneration and nerve repair in preclinical models by activation of small GTPase RhoA and its downstream effectors. The objective of this study was to determine whether erythropoietin (EPO), a pleiotropic cytokine with neuroprotective and neurotrophic properties, enhances nerve regeneration in preclinical cell culture and animal models of autoimmune neuropathy/nerve repair generated with monoclonal and patient derived Abs. Primary neuronal cultures and a standardized sciatic crush nerve model were used to assess the efficacy of EPO in reversing inhibitory effects of anti-ganglioside Abs on nerve repair. We found that EPO completely reversed the inhibitory effects of anti-ganglioside Abs on axon regeneration in cell culture models and significantly improved nerve regeneration/repair in an animal model. Moreover, EPO-induced proregenerative effects in nerve cells are through EPO receptors and Janus kinase 2/Signal transducer and activator of transcription 5 pathway and not via early direct modulation of small GTPase RhoA. These preclinical studies indicate that EPO is a viable candidate drug to develop further for neuroprotection and enhancing nerve repair in patients with GBS.

  19. Erythropoietin promotes survival and regeneration of insect neurons in vivo and in vitro.

    PubMed

    Ostrowski, D; Ehrenreich, H; Heinrich, R

    2011-08-11

    In addition to its function as a regulator of hematopoiesis, the cytokine erythropoietin (Epo) initiates adaptive cellular responses to both moderate environmental challenges and tissue damaging insults in various non-hematopoietic mammalian tissues. Epo's neuroprotective and neuroregenerative functions mediated through janus kinases (JAK)/signal transducers and activators of transcription (STAT) transduction pathways and regulation of Epo and Epo receptor expression in the nervous system by hypoxia inducible factor (HIF) have been documented in a variety of in vitro and in vivo studies and homologs of the human Epo gene are present in fish, amphibians and mammals. The present study reproduces the hallmarks of Epo-mediated mammalian neuroprotection in the grasshopper nervous system. Recombinant human Epo (rhEpo) increases the survival of dissociated grasshopper brain neurons under normoxic and hypoxic conditions and promotes the regeneration of neurites in vitro. In addition, reestablishment of sound source localization after unilateral tympanic nerve crush injury was accelerated and more complete after application of rhEpo, demonstrating in vivo support of auditory receptor cell axon regeneration. Immunoblots of central nervous tissue extracts from mouse, grasshopper, crayfish and leech labeled protein bands of ∼38 kDa, fitting to the molecular weight of Epo reported in earlier studies. These results indicate that a ligand/receptor system that shares structural and functional similarities with mammalian Epo and Epo receptor exerts neuroprotective and neuroregenerative effects in insects. With both upstream (HIF system) and downstream (JAK/STAT pathway) elements of the mammalian Epo system being present in insects and other invertebrates, Epo-like signaling involved in tissue protection appears to be an ancient beneficial function shared by vertebrates and invertebrates.

  20. Endoplasmic reticulum stress signal impairs erythropoietin production: a role for ATF4.

    PubMed

    Chiang, Chih-Kang; Nangaku, Masaomi; Tanaka, Tetsuhiro; Iwawaki, Takao; Inagi, Reiko

    2013-02-15

    Hypoxia upregulates the hypoxia-inducible factor (HIF) pathway and the endoplasmic reticulum (ER) stress signal, unfolded protein response (UPR). The cross talk of both signals affects the pathogenic alteration by hypoxia. Here we showed that ER stress induced by tunicamycin or thapsigargin suppressed inducible (CoCl(2) or hypoxia) transcription of erythropoietin (EPO), a representative HIF target gene, in HepG2. This suppression was inversely correlated with UPR activation, as estimated by expression of the UPR regulator glucose-regulated protein 78, and restored by an ER stress inhibitor, salubrinal, in association with normalization of the UPR state. Importantly, the decreased EPO expression was also observed in HepG2 overexpressing UPR activating transcription factor (ATF)4. Overexpression of mutated ATF4 that lacks the transcriptional activity did not alter EPO transcriptional regulation. Transcriptional activity of the EPO 3'-enhancer, which is mainly regulated by HIF, was abolished by both ER stressors and ATF4 overexpression, while nuclear HIF accumulation or expression of other HIF target genes was not suppressed by ER stress. Chromatin immunoprecipitation analysis identified a novel ATF4 binding site (TGACCTCT) within the EPO 3'-enhancer region, suggesting a distinct role for ATF4 in UPR-dependent suppression of the enhancer. Induction of ER stress in rat liver and kidney by tunicamycin decreased the hepatic and renal mRNA and plasma level of EPO. Collectively, ER stress selectively impairs the transcriptional activity of EPO but not of other HIF target genes. This effect is mediated by suppression of EPO 3'-enhancer activity via ATF4 without any direct effect on HIF, indicating that UPR contributes to oxygen-sensing regulation of EPO.

  1. Protective effects of erythropoietin on endotoxin-related organ injury in rats.

    PubMed

    Li, Xiu-jiang; Zhang, Guo-xing; Sun, Ni; Sun, Yu; Yang, Li-zhi; Du, Yu-jun

    2013-10-01

    The protective effect of erythropoietin (EPO) on tissues following ischemia and reperfusion injuries remains poorly understood. We aimed to investigate the effect of EPO in preventing endotoxin-induced organ damage. Rat model of multiple organ failure (MOF) was established by tail vein injection of 10 mg/kg lipopolysaccharide (LPS). Recombinant human EPO treatment (5000 U/kg) was administered by tail vein injection at 30 min after LPS challenge. Twenty-four h after EPO treatment, changes in serum enzyme levels, including aspartate aminotransferase (AST), alanine transaminase (ALT), blood urea nitrogen (BUN) and creatinine (Cr), were evaluated by biochemical analysis. Serum levels of tumor necrosis factor-α (TNF-α) were determined by using immunoradiometric assay. Histological examination of tissue sections was carried out by hematoxylin and eosin staining, while ultrastructure evaluation of organ tissues was assessed by transmission electron microscopy. Protein expression levels were detected by using Western blotting. EPO treatment showed a modest effect in preventing LPS-induced elevation of AST, ALT, BUN, Cr, and TNF-α levels, and in protecting against LPS-induced tissue degeneration and injured ultrastructure in the lung, liver, and kidney. Moreover, LPS promoted phosphorylation of alanine aminotransferase (AKT) and increased nuclear factor-κB (NF-κB) activation in the lung, liver, and kidney (P<0.05 vs. control). However, EPO treatment significantly decreased the LPS-induced pAKT up-regulation in these tissues (P<0.05 vs. LPS treatment alone). The present study demonstrates that EPO may play a protective role against LPS-induced MOF by reducing the inflammatory response and tissue degeneration, possibly via the phosphatidylinositol 3-kinase/AKT and NF-κB signaling pathways.

  2. Activation and inhibition of erythropoietin receptor function: role of receptor dimerization.

    PubMed Central

    Watowich, S S; Hilton, D J; Lodish, H F

    1994-01-01

    Members of the cytokine receptor superfamily have structurally similar extracellular ligand-binding domains yet diverse cytoplasmic regions lacking any obvious catalytic domains. Many of these receptors form ligand-induced oligomers which are likely to participate in transmembrane signaling. A constitutively active (factor-independent) mutant of the erythropoietin receptor (EPO-R), R129C in the exoplasmic domain, forms disulfide-linked homodimers, suggesting that the wild-type EPO-R is activated by ligand-induced homodimerization. Here, we have taken two approaches to probe the role EPO-R dimerization plays in signal transduction. First, on the basis of the crystal structure of the ligand-bound, homodimeric growth hormone receptor (GH-R) and sequence alignment between the GH-R and EPO-R, we identified residues of the EPO-R which may be involved in intersubunit contacts in an EPO-R homodimer. Residue 129 of the EPO-R corresponds to a residue localized to the GH-R dimer interface region. Alanine or cysteine substitutions were introduced at four other residues of the EPO-R predicted to be in the dimer interface region. Substitution of residue E-132 or E-133 with cysteine renders the EPO-R constitutively active. Like the arginine-to-cysteine mutation at position 129 in the exoplasmic domain (R129C), E132C and E133C form disulfide-linked homodimers, suggesting that constitutive activity is due to covalent dimerization. In the second approach, we have coexpressed the wild-type EPO-R with inactive mutants of the receptor missing all or part of the cytosolic domain. These truncated receptors have a dominant inhibitory effect on the proliferative action of the wild-type receptor. Taken together, these results strengthen the hypothesis that an initial step in EPO- and EPO-R-mediated signal transduction is ligand-induced receptor dimerization. Images PMID:8196600

  3. Mitogenic effect of erythropoietin on neonatal rat cardiomyocytes: signal transduction pathways.

    PubMed

    Wald, M R; Borda, E S; Sterin-Borda, L

    1996-06-01

    The mitogenic effect of recombinant human erythropoietin (rHuEpo) on primary cultures of neonatal rat cardiac myocytes was observed. rHuEpo triggered a dose-dependent increase in myocyte proliferation. The hormone effect over optimally grown control culture 1 day after addition was maximum with 0.5 U/ml and was inhibited with anti-rHuEpo. Inhibitors of enzymatic pathways known to be involved in the cytokines intracellular mechanism such as genistein (tyrosine kinase inhibitor), 2-nitro-4-carboxyphenyl-N,N-diphenylcarbamate (phospholipase C [PLC] inhibitor), and 1-(5-isoquinolinylsulfonyl)-2-methyl-piperazine (protein kinase C [PKC] inhibitor) prevented the mitogenic action of rHuEpo. Also the inhibition of Na(+)-K(+)-ATPase activity by ouabain blunted the stimulatory action of rHuEpo on cell proliferation. The mitogenic action of the hormone was correlated with cardiac membrane paranitrophenylphosphatase (pNPPase) and PKC activity, since concentrations of rHuEpo that stimulate DNA synthesis increased pNPPase and PKC activity. Moreover, the enzymatic inhibition of tyrosine kinase, PLC, and PKC attenuated the stimulatory action of rHuEpo upon cardiac pNPPase activity. In this paper we demonstrate a non-hematopoietic action of rHuEpo showing both mitogenic and enzymatic effect upon primary myocyte cell culture and on pNPPase activity of neonatal rat heart. These effects are related to the capacity of rHuEpo to stimulate Na(+)-K(+)-ATPase activity and appear to be secondary to the activation of tyrosine kinase and PKC, indicating that in the rHuEpo mediated mitogenic action on cardiomyocytes involves the activation of the same enzymatic pathways that have been described by other cytokines in different tissues.

  4. Serum erythropoietin concentrations in symptomatic infants during the anaemia of prematurity.

    PubMed Central

    Meyer, J; Sive, A; Jacobs, P

    1992-01-01

    A comparison was carried out between a series of neonates who weighed less than 1500 g at birth and received red cell transfusions for symptomatic anaemia of prematurity (group 1, n = 14) and controls of similar gestational age and weight, who remained well and were not transfused during their nursery stay (group 2, n = 10). Mean (SD) haemoglobin concentrations at birth were 163 (12) g/l and 183 (17) g/l (p = 0.004), respectively. Transfusion resulted in significantly better weight gain in six infants who had been growing poorly:mean (SE) 8.8 (2.8) g/day improved to 23.3 (2.1) g/day (p less than 0.002). Geometric mean (SD) serum immunoreactive erythropoietin (SiEp) concentrations (17.7 (1.3) U/l) for the whole group of infants were similar to those of normal adults (17.4 (4.7) U/l) despite considerably reduced haemoglobin values. There was a significant inverse correlation between haemoglobin and log SiEp concentrations in the infants requiring transfusion (r = -0.43; p less than 0.01), but this was not apparent in the untransfused babies. Moreover, at haemoglobin concentrations below 120 g/l the mean (SE) SiEp concentration of 20 (1.08) U/l in group 1 was significantly higher than in group 2 (14 (1.06) U/l; p = 0.002). These data suggest that an increased concentration of SiEp early in the course of the anaemia of prematurity helps to identify those infants who would benefit from red cell transfusions, but that clinical criteria, although ill defined, do so equally well. PMID:1519982

  5. Erythropoietin Does Not Enhance Skeletal Muscle Protein Synthesis Following Exercise in Young and Older Adults

    PubMed Central

    Lamon, Séverine; Zacharewicz, Evelyn; Arentson-Lantz, Emily; Gatta, Paul A. Della; Ghobrial, Lobna; Gerlinger-Romero, Frederico; Garnham, Andrew; Paddon-Jones, Douglas; Russell, Aaron P.

    2016-01-01

    Purpose: Erythropoietin (EPO) is a renal cytokine that is primarily involved in hematopoiesis while also playing a role in non-hematopoietic tissues expressing the EPO-receptor (EPOR). The EPOR is present in human skeletal muscle. In mouse skeletal muscle, EPO stimulation can activate the AKT serine/threonine kinase 1 (AKT) signaling pathway, the main positive regulator of muscle protein synthesis. We hypothesized that a single intravenous EPO injection combined with acute resistance exercise would have a synergistic effect on skeletal muscle protein synthesis via activation of the AKT pathway. Methods: Ten young (24.2 ± 0.9 years) and 10 older (66.6 ± 1.1 years) healthy subjects received a primed, constant infusion of [ring-13C6] L-phenylalanine and a single injection of 10,000 IU epoetin-beta or placebo in a double-blind randomized, cross-over design. 2 h after the injection, the subjects completed an acute bout of leg extension resistance exercise to stimulate skeletal muscle protein synthesis. Results: Significant interaction effects in the phosphorylation levels of the members of the AKT signaling pathway indicated a differential activation of protein synthesis signaling in older subjects when compared to young subjects. However, EPO offered no synergistic effect on vastus lateralis mixed muscle protein synthesis rate in young or older subjects. Conclusions: Despite its ability to activate the AKT pathway in skeletal muscle, an acute EPO injection had no additive or synergistic effect on the exercise-induced activation of muscle protein synthesis or muscle protein synthesis signaling pathways. PMID:27458387

  6. The Greatly Misunderstood Erythropoietin Resistance Index and the Case for a New Responsiveness Measure

    PubMed Central

    Chait, Y; Kalim, S; Horowitz, J; Hollot, CH; Ankers, ED; Germain, MJ; Thadhani, RI

    2016-01-01

    Background The optimal use of erythropoiesis stimulating agents (ESAs) to treat anemia in end stage renal disease (ESRD) remains controversial due to reported associations with adverse events. In analyzing these associations, studies often utilize ESA resistance indices (ERIs), to characterize a patient’s response to ESA. In this study, we examine whether ERI is an adequate measure of ESA resistance. Methods We used retrospective data from a non-concurrent cohort study of incident hemodialysis patients in the United States (n=9386). ERI is defined as average weekly erythropoietin (EPO) dose per kg body weight (wt) per average hemoglobin (Hgb), over a 3-month period (ERI = (EPO/wt)/Hgb). Linear regression was used to demonstrate the relationship between ERI and weight-adjusted EPO. The coefficient of variation (CV) was used to compare the variability of Hgb with that of weight-adjusted EPO in order to explain this relationship. This analysis was done for each quarter during the first year of dialysis. Results ERI is strongly linearly related with weight-adjusted EPO dose in each of the 4 quarters by the equation ERI = 0.0899*(EPO/wt) (range of R2 = 0.97–0.98) and weakly linearly related to 1/Hgb (range of R2 = 0.06–0.16). These correlations hold independent of age, sex, hgb level, ERI level, and epo-naïve stratifications. Conclusions ERI is strongly linearly related to weight-adjusted (and non-weight-adjusted) EPO dose by a “universal”, not patient-specific formula, and thus is a surrogate of EPO dose. Therefore, associations between ERI and clinical outcomes are associations between a confounded EPO dose and those outcomes. PMID:26843352

  7. Effect of erythropoietin loading chitosan-tripolyphosphate nanoparticles on an IgA nephropathy rat model

    PubMed Central

    ZHANG, XIAOLI; WU, YIN; SUN, KUN; TAN, JING

    2014-01-01

    The aim of the present study was to investigate the effect of erythropoietin (EPO) loading chitosan-tripolyphosphate (CS-TPP) nanoparticles on an immunoglobulin A nephropathy (IgAN) rat model. CS-TPP nanoparticles were produced from CS and TPP and EPO was loaded by mixing with the nanoparticles. The IgAN rat models were randomly divided into three groups: the CS-TPP-EPO group, CS-TPP group and EPO group. Hemoglobin (Hb), blood urea nitrogen (BUN) and creatinine (Cr) levels were measured in each group using a Biochemical Analyzer (Hitachi, Tokyo, Japan). The average size of nanoparticles was 485±12 nm and the encapsulation efficiency of EPO was 78.45%. The EPO release curve in CS-TPP-EPO nanoparticles exhibited a biphasic distribution in vitro. The levels of BUN and Cr in the CS-TPP-EPO group were significantly lower compared with the control group (P<0.05); however, the level of Hb in the CS-TPP-EPO group was higher compared with the other groups (P<0.05). The changes in Hb, BUN and Cr in the CS-TPP-EPO group were maintained for less than one week following the end of the treatment with CS-TPP-EPO nanoparticles. In conclusion, the CS-TPP-EPO nanoparticles had a lower toxicity compared with EPO and CS-TPP treatment. Furthermore, CS-TPP-EPO may improve the therapeutic effect in the IgAN model. This suggests that CS-TPP-EPO nanoparticles may be a potential therapeutic drug for the treatment of patients with IgAN. PMID:24926362

  8. Erythropoietin and respiratory control at adulthood and during early postnatal life.

    PubMed

    Soliz, Jorge

    2013-01-01

    Erythropoietin (Epo) was originally discovered as a cytokine able to increase the production of red blood cells upon conditions of reduced oxygen availability. Now we know that Epo does far more than "only" augmenting the number of erythrocytes. Since the demonstration that Epo (and its receptor) is expressed in the mammalian brain, several elegant experiments were performed to reveal the function of this molecule in the neuronal tissue. Accordingly to its anti-apoptotic, neurotrophic and proliferative effects in the bone marrow, it was suitably suggested that upon pathological conditions Epo exerts neuroprotective functions (i.e. reducing the infarct volume of stroke, thus allowing better and faster recovery). We considered however, that Epo in brain might also exert a physiological function. Indeed, we found that Epo is an important modulator of the respiratory control system. By using adult mice we showed that Epo increases the hypoxic ventilatory response by interacting with both the central respiratory network (brainstem) as well as the main peripheral sensory organs detecting systemic hypoxia, the carotid bodies. More recently, our research turned to examine the exciting hypothesis that Epo is also implicated in the regulation of the neuronal control of ventilation during the postnatal development. The objective of this review is to summarize the role and mode of action of Epo on respiratory control in adult mammals and highlight the potential pathways by which this cytokine achieve this function. Additionally, we review recent evidences showing that Epo play a crucial role in setting the respiratory motor output (measured on the isolated brainstem spinal cord preparation, en bloc technique) during the early postnatal life.

  9. The Neuroprotective Mechanism of Erythropoietin-TAT Fusion Protein Against Neurodegeneration from Ischemic Brain Injury.

    PubMed

    Liu, P; Liu, X; Akf Liou, Emptyyn Y; Xing, J; Jing, Z; Ji, X; Liu, X; Zhao, H; Yan, F; Chen, J; Cao, G; Luo, Y

    2013-08-27

    Aims: To compare the neuroprotection of erythropoietin (EPO) and EPO fusion protein containing transduction domain derived from HIV TAT (EPO-TAT) against ischemic brain injury, inclusive of the side effect, and explore the mechanism underlying the role of EPO-TAT in a transient focal cerebral ischemia model in rats. Methods: Transient focal ischemia was induced by middle cerebral artery occlusion (MCAO) in rats. Rats were treated, respectively, with following regimens: saline, 1000 U/kg EPO, 5000 U/kg EPO, 1000 U/kg EPO-TAT, 1000 U/kg EPO-TAT + 5 µl of 10 mM LY294002 (or/plus 5 µl of 5 mM PD98059). Neurological deficit scores, infarct volume, and hematologic side effect were assessed at 72 hours after MCAO. Apoptotic cells were determined with TUNEL staining. The expression and localization of phosphorylated AKT (pAKT) and phosphorylated ERK (pERK) were detected with Western blot, immunohistochemistry, and immunofluorescence, respectively. Results: 1000 U/kg EPO-TAT exhibited a comparable neuroprotection to 5000 U/kg EPO, as evidenced by a comparable attenuation in neurological deficit, infarct volume, and number of apoptotic cells in the rat ischemic cortex after MCAO. The pAKT and pERK levels were significantly elevated solely in neurons of rodents receiving EPO or EPO-TAT treatments, suggesting the concurrent activation of these two pathways. Specific inhibition of either AKT or ERK pathway partially abolished EPO-TAT protection, but exhibited no influence on the activation status of its counterpart, suggesting no cross-modulation between these two protective pathways. Conclusion: Our study indicates that EPO-TAT at 1000 U/kg displays neuroprotection with no detectable side effects. The mechanism for neuroprotection may be attributable to the simultaneous activation of the AKT and ERK pathways, which preserve neuronal cell viability and attenuate behavioral deficits.

  10. Plasma soluble erythropoietin receptor is decreased during sleep in Andean highlanders with Chronic Mountain Sickness

    PubMed Central

    Corante, Noemí; Anza-Ramírez, Cecilia; Figueroa-Mujíca, Rómulo; Vizcardo-Galindo, Gustavo; Mercado, Andy; Macarlupú, José Luis; León-Velarde, Fabiola

    2016-01-01

    Excessive erythrocytosis (EE) is the main sign of Chronic Mountain Sickness (CMS), a highly prevalent syndrome in Andean highlanders. Low pulse O2 saturation (SpO2) during sleep and serum androgens have been suggested to contribute to EE in CMS patients. However, whether these factors have a significant impact on the erythropoietin (Epo) system leading to EE is still unclear. We have recently shown that morning soluble Epo receptor (sEpoR), an endogenous Epo antagonist, is decreased in CMS patients suggesting increased Epo availability (increased Epo/sEpoR). The present study aimed to characterize the nocturnal concentration profile of sEpoR and Epo and their relationship with SpO2, Hct, and serum testosterone in healthy highlanders (HH) and CMS patients. Epo and sEpoR concentrations were evaluated every 4 h (6 PM to 6 AM) and nighttime SpO2 was continuously monitored (10 PM to 6 AM) in 39 male participants (CMS, n = 23; HH, n = 16) aged 21-65 yr from Cerro de Pasco, Peru (4,340 m). CMS patients showed higher serum Epo concentrations throughout the night and lower sEpoR from 10 PM to 6 AM. Consequently, Epo/sEpoR was significantly higher in the CMS group at every time point. Mean sleep-time SpO2 was lower in CMS patients compared with HH, while the percentage of sleep time spent with SpO2 < 80% was higher. Multiple-regression analysis showed mean sleep-time SpO2 and Epo/sEpoR as significant predictors of hematocrit corrected for potential confounders (age, body mass index, and testosterone). Testosterone levels were associated neither with Hct nor with erythropoietic factors. In conclusion, our results show sustained erythropoietic stimulus driven by the Epo system in CMS patients, further enhanced by a continuous exposure to accentuated nocturnal hypoxemia. PMID:27125843

  11. Erythropoietin triggers a burst of GATA-1 in normal human erythroid cells differentiating in tissue culture.

    PubMed Central

    Dalyot, N; Fibach, E; Ronchi, A; Rachmilewitz, E A; Ottolenghi, S; Oppenheim, A

    1993-01-01

    GATA-1 is a central transcription-activator of erythroid differentiation. In the present work we have studied the kinetics of its expression and activity during development of normal human erythroid progenitors, grown in primary cultures. In response to the addition of erythropoietin (Epo), the cells undergo proliferation and differentiation in a synchronized fashion. This recently developed experimental system allows biochemical dissection of erythroid differentiation in a physiological meaningful environment. No DNA-binding activity of GATA-1 could be detected before the addition of Epo, although a very low level of mRNA was observed. Following Epo addition there was a sharp parallel rise in both mRNA and DNA-binding activity, consistent with positive autoregulation of the GATA-1 gene. After reaching a peak on day 7-9, both mRNA and protein activity decreased. The binding activity of the ubiquitous factor SP1 showed a biphasic pattern; its second peak usually coincided with the GATA-1 peak, suggesting that SP1 also plays a specific role in erythroid maturation. The highest activity of GATA-1 per erythroid cell was found on day 6-8, immediately preceding the major rise in globin gene mRNA and in the number of hemoglobinized cells. The results imply that a high level of GATA-1 activity is necessary for globin gene expression and erythroid maturation, suggesting that a requirement for a threshold concentration of GATA-1 is part of the mechanism that determines the final steps of erythroid maturation. Images PMID:8371977

  12. Human recombinant erythropoietin (rEpo) has no effect on tumour growth or angiogenesis.

    PubMed

    Hardee, M E; Kirkpatrick, J P; Shan, S; Snyder, S A; Vujaskovic, Z; Rabbani, Z N; Dewhirst, M W; Blackwell, K L

    2005-12-12

    Tumour hypoxia has been shown to increase mutation rate, angiogenesis, and metastatic potential, and decrease response to conventional therapeutics. Improved tumour oxygenation should translate into increased treatment response. Exogenous recombinant erythropoietin (rEpo) has been recently shown to increase tumour oxygenation in a mammary carcinoma model. The mechanism of this action is not yet understood completely. The presence of Epo and its receptor (EpoR) have been demonstrated on several normal and neoplastic tissues, including blood vessels and various solid tumours. In addition, rEpo has been shown in two recent prospective, randomized clinical trials to negatively impact treatment outcome. In this study, we attempt to characterize the direct effects of rEpo on tumour growth and angiogenesis in two separate rodent carcinomas. The effect of rEpo on R3230 rat mammary adenocarcinomas, CT-26 mouse colon carcinomas, HCT-116 human colon carcinomas, and FaDu human head and neck tumours, all of which express EpoR, was examined. There were no differences in tumour growth or proliferation (measured by Ki-67) between placebo-treated and rEpo-treated tumours. In the mammary window chamber, vascular length density (VLD) measurements in serial images of both placebo-treated and Epo-treated rats revealed no difference in angiogenesis between the Epo-treated tumours and placebo-treated tumours at any time point. These experiments are important because they suggest that the recent clinical detriment seen with the use of Epo is not due to its tumour growth effects or angiogenesis. These studies also suggest that further preclinical studies need to examine rEpo's direct tumour effects in efforts to improve the therapeutic benefits of Epo in solid tumour patients.

  13. Lenalidomide Stabilizes the Erythropoietin Receptor by Inhibiting the E3 Ubiquitin Ligase RNF41.

    PubMed

    Basiorka, Ashley A; McGraw, Kathy L; De Ceuninck, Leentje; Griner, Lori N; Zhang, Ling; Clark, Justine A; Caceres, Gisela; Sokol, Lubomir; Komrokji, Rami S; Reuther, Gary W; Wei, Sheng; Tavernier, Jan; List, Alan F

    2016-06-15

    In a subset of patients with non-del(5q) myelodysplastic syndrome (MDS), lenalidomide promotes erythroid lineage competence and effective erythropoiesis. To determine the mechanism by which lenalidomide promotes erythropoiesis, we investigated its action on erythropoietin receptor (EpoR) cellular dynamics. Lenalidomide upregulated expression and stability of JAK2-associated EpoR in UT7 erythroid cells and primary CD71+ erythroid progenitors. The effects of lenalidomide on receptor turnover were Type I cytokine receptor specific, as evidenced by coregulation of the IL3-Rα receptor but not c-Kit. To elucidate this mechanism, we investigated the effects of lenalidomide on the E3 ubiquitin ligase RNF41. Lenalidomide promoted EpoR/RNF41 association and inhibited RNF41 auto-ubiquitination, accompanied by a reduction in EpoR ubiquitination. To confirm that RNF41 is the principal target responsible for EpoR stabilization, HEK293T cells were transfected with EpoR and/or RNF41 gene expression vectors. Steady-state EpoR expression was reduced in EpoR/RNF41 cells, whereas EpoR upregulation by lenalidomide was abrogated, indicating that cellular RNF41 is a critical determinant of drug-induced receptor modulation. Notably, shRNA suppression of CRBN gene expression failed to alter EpoR upregulation, indicating that drug-induced receptor modulation is independent of cereblon. Immunohistochemical staining showed that RNF41 expression decreased in primary erythroid cells of lenalidomide-responding patients, suggesting that cellular RNF41 expression merits investigation as a biomarker for lenalidomide response. Our findings indicate that lenalidomide has E3 ubiquitin ligase inhibitory effects that extend to RNF41 and that inhibition of RNF41 auto-ubiquitination promotes membrane accumulation of signaling competent JAK2/EpoR complexes that augment Epo responsiveness. Cancer Res; 76(12); 3531-40. ©2016 AACR.

  14. Cessation of intensive treatment with recombinant human erythropoietin is followed by secondary anemia.

    PubMed

    Piron, M; Loo, M; Gothot, A; Tassin, F; Fillet, G; Beguin, Y

    2001-01-15

    Little information is available on the evolution of erythropoiesis after interruption of recombinant human erythropoietin (rHuEpo) therapy. Iron-overloaded rats received 20 daily injections of rHuEpo. During treatment, reticulocytes, soluble transferrin receptor (sTfR), and hematocrit increased progressively. This was accompanied by a substantial expansion of spleen erythropoiesis but a decrease in the bone marrow. Five weeks after treatment, rats developed a significant degree of a regenerative anemia. Erythropoietic activity, as assessed by reticulocytes, sTfR, erythroid cellularity, iron incorporation into heme, and the number of erythroid colonies, was severely depressed 3 weeks after cessation of rHuEpo. This was followed by regeneration of erythroblasts and reticulocytes at weeks 6 to 7 post-Epo, but erythroid progenitors recovered only partially by that time. The anemia was definitely corrected 2 months after cessation of rHuEpo treatment. Serum Epo levels remained elevated for several weeks, but the sensitivity of marrow erythroid precursors to Epo was preserved. No rat antibodies to rHuEpo were detected, and serum from post-Epo animals did not exert any inhibitory activity on erythropoiesis. In conclusion, after cessation of intensive rHuEpo therapy, there was a strong inhibition of erythropoietic activity with secondary anemia followed by late recovery. This was not due to antibodies or other soluble inhibitory factors, a defect in endogenous Epo production, or a loss of sensitivity to Epo. This may rather represent intrinsic erythroid marrow exhaustion, mostly at the level of erythroid progenitors but also at later stages of erythropoiesis.

  15. Plasma soluble erythropoietin receptor is decreased during sleep in Andean highlanders with Chronic Mountain Sickness.

    PubMed

    Villafuerte, Francisco C; Corante, Noemí; Anza-Ramírez, Cecilia; Figueroa-Mujíca, Rómulo; Vizcardo-Galindo, Gustavo; Mercado, Andy; Macarlupú, José Luis; León-Velarde, Fabiola

    2016-07-01

    Excessive erythrocytosis (EE) is the main sign of Chronic Mountain Sickness (CMS), a highly prevalent syndrome in Andean highlanders. Low pulse O2 saturation (SpO2) during sleep and serum androgens have been suggested to contribute to EE in CMS patients. However, whether these factors have a significant impact on the erythropoietin (Epo) system leading to EE is still unclear. We have recently shown that morning soluble Epo receptor (sEpoR), an endogenous Epo antagonist, is decreased in CMS patients suggesting increased Epo availability (increased Epo/sEpoR). The present study aimed to characterize the nocturnal concentration profile of sEpoR and Epo and their relationship with SpO2, Hct, and serum testosterone in healthy highlanders (HH) and CMS patients. Epo and sEpoR concentrations were evaluated every 4 h (6 PM to 6 AM) and nighttime SpO2 was continuously monitored (10 PM to 6 AM) in 39 male participants (CMS, n = 23; HH, n = 16) aged 21-65 yr from Cerro de Pasco, Peru (4,340 m). CMS patients showed higher serum Epo concentrations throughout the night and lower sEpoR from 10 PM to 6 AM. Consequently, Epo/sEpoR was significantly higher in the CMS group at every time point. Mean sleep-time SpO2 was lower in CMS patients compared with HH, while the percentage of sleep time spent with SpO2 < 80% was higher. Multiple-regression analysis showed mean sleep-time SpO2 and Epo/sEpoR as significant predictors of hematocrit corrected for potential confounders (age, body mass index, and testosterone). Testosterone levels were associated neither with Hct nor with erythropoietic factors. In conclusion, our results show sustained erythropoietic stimulus driven by the Epo system in CMS patients, further enhanced by a continuous exposure to accentuated nocturnal hypoxemia.

  16. Erythropoietin promotes neurovascular remodeling and long-term functional recovery in rats following traumatic brain injury

    PubMed Central

    Ning, Ruizhuo; Xiong, Ye; Mahmood, Asim; Zhang, Yanlu; Meng, Yuling; Qu, Changsheng; Chopp, Michael

    2011-01-01

    Erythropoietin (EPO) improves functional recovery after traumatic brain injury (TBI). This study was designed to investigate long-term (3 mo) effects of EPO on brain remodeling and functional recovery in rats after TBI. Young male Wistar rats were subjected to unilateral controlled cortical impact injury. TBI rats were divided into the following groups: 1) Saline group (n = 7); 2) EPO-6h group (n = 8); and 3) EPO-24h group (n = 8). EPO (5,000 U/kg in saline) was administered intraperitoneally at 6 h, and 1 and 2 days (EPO-6h group) or at 1, 2, and 3 days (EPO-24h group) post injury. Neurological function was assessed using a modified neurological severity score, footfault and Morris water maze tests. Animals were sacrificed at 3 mos after injury and brain sections stained for immunohistochemical analyses. Compared to the saline, EPO-6h treatment significantly reduced cortical lesion volume, while EPO-24h therapy did not affect the lesion volume (P<0.05). Both the EPO-6h and EPO-24h treatments significantly reduced hippocampal cell loss (P<0.05), promoted angiogenesis (P<0.05) and increased endogenous cellular proliferation (BrdU-positive cells) in the injury boundary zone and hippocampus (P<0.05) compared to saline controls. Significantly enhanced neurogenesis (BrdU/NeuN-positive cells) was seen in the dentate gyrus of both EPO groups compared to the saline group. Both EPO treatments significantly improved long-term sensorimotor and cognitive functional recovery after TBI. In conclusion, the beneficial effects of posttraumatic EPO treatment on injured brain persisted for at least 3 months. The long-term improvement in functional outcome may in part be related to the neurovascular remodeling induced by EPO. PMID:21295557

  17. Recombinant erythropoietin is neuroprotective in a novel mouse oxidative injury model.

    PubMed

    Juul, Sandra E; McPherson, Ronald J; Bammler, Theodor K; Wilkerson, Jasmine; Beyer, Richard P; Farin, Federico M

    2008-01-01

    To identify neuroprotective changes in gene expression, we developed a neonatal mouse model of moderate to severe oxidative brain injury and hypothesized that recombinant erythropoietin (rEpo) would decrease the expression of proapoptotic and proinflammatory genes 24 and 48 h, respectively, after injury and increase the expression of neurogenic and angiogenic genes 168 h after injury. Postnatal day 10 BALB-c mice underwent sham surgery or right common carotid artery occlusion followed by alternating hypoxia and hyperoxia and were then treated with rEpo (5,000 U/kg s.c.) or saline (vehicle) daily for up to three doses. At death, gross brain injury was assessed, then hippocampus, cortex, and thalamus were isolated for RNA or protein extraction. Microarray analysis, real-time polymerase chain reaction, and Bio-Plex suspension array system validation were performed. rEpo decreased both incidence and severity of brain injury (median injury score 3 vs. 0, p < 0.0001) and reduced the injury-induced increases in interleukin-1alpha and interleukin-6 gene expression (p < 0.001), with corresponding effects on protein translation. Similarly, the expression of caspase-1, caspase-4, and caspase-6 and of p53 was increased by brain injury at 24 h, but mitigated by rEpo (p < 0.01). The interleukin-10 expression was higher in the rEpo-treated animals. Apoptotic and proinflammatory gene expression persisted for 168 h. There was no increase in angiogenic gene expression at the time points studied.

  18. Enhanced sialylation of recombinant erythropoietin in CHO cells by human glycosyltransferase expression.

    PubMed

    Jeong, Yeon Tae; Choi, One; Lim, Hye Rim; Son, Young Dok; Kim, Hong Jin; Kim, Jung Hoe

    2008-12-01

    Sialylation, the attachment of sialic acid residues to a protein, can affect the biological activity and in vivo circulatory half-life of glycoproteins. Human alpha2,3- sialyltransferase (alpha2,3-ST) and beta1,4-galactosyltransferase (beta1,4-GT) are responsible for terminal sialylation and galactosylation, respectively. Enhanced sialylation of human erythropoietin (EPO) by the expression of alpha2,3-ST and beta1,4-GT was achieved using recombinant Chinese hamster ovary (CHO) cells (EC1). The sialic acid content and sialylation of N-glycans were evaluated by HPLC. When alpha2,3-ST was expressed in CHO cells (EC1-ST2), the sialic acid content (moles of sialic acid/mole of EPO) increased from 6.7 to 7.5. In addition, the amount of trisialylated glycans increased from 17.3% to 26.1%. When alpha2,3-ST and beta1,4-GT were coexpressed in CHO cells (EC1-GTST15), the degree of sialylation was greater than that in EC1-ST2 cells. In the case of EC1-GTST15 cells, the sialic acid content increased to 8.2 and the proportion of trisialylated glycans was markedly increased from 17.3% to 35.5%. Interestingly, the amount of asialoglycans decreased only in the case of GTST15 cells (21.4% to 14.2%). These results show that coexpression of alpha2,3- ST and beta1,4-GT is more effective than the expression of alpha2,3-ST alone. Coexpression of alpha2,3-ST and beta1,4-GT did not affect CHO cell growth and metabolism or EPO production. Thus, coexpression of alpha2,3-ST and beta1,4-GT may be beneficial for producing therapeutic glycoproteins with enhanced sialylation in CHO cells.

  19. Enhanced sialylation of recombinant erythropoietin in genetically engineered Chinese-hamster ovary cells.

    PubMed

    Jeong, Yeon Tae; Choi, One; Son, Young Dok; Park, Seung Yeol; Kim, Jung Hoe

    2009-04-01

    Sialic acid, the terminal sugar in N-linked complex glycans, is usually found in glycoproteins and plays a major role in determining the circulatory lifespan of glycoproteins. In the present study we attempted to enhance the sialylation of recombinant EPO (erythropoietin) in CHO (Chinese-hamster ovary) cells. To enhance EPO sialylation, we introduced human alpha2,3-ST (alpha2,3-sialyltransferase) and CMP-SAS (CMP-sialic acid synthase) into recombinant human EPO-producing CHO cells. The sialylation of EPO was increased by the expression of alpha2,3-ST alone. Although the co-expression of alpha2,3-ST and CMP-SAS did not further increase sialylation, an increase in the intracellular pool of CMP-sialic acid was noted. On the basis of these observations, it was postulated that the transport capacity of CMP-sialic acid into the Golgi lumen was limited, thereby causing the reduced availability of CMP-sialic acid substrate for sialylation. Therefore, we co-expressed human alpha2,3-ST and CMP-SAS, as well as overexpress Chinese hamster CMP-sialic acid transporter (CMP-SAT) in CHO cells, which produced recombinant human EPO. When alpha2,3-ST, CMP-SAS, and CMP-SAT were overexpressed in CHO cells, there was a corresponding increase in sialylation compared with the co-expression of alpha2,3-ST and CMP-SAS. The present study provides a useful strategy for enhancing the sialylation of therapeutic glycoproteins produced in CHO cells.

  20. Molecular Design, Expression and Evaluation of PASylated Human Recombinant Erythropoietin with Enhanced Functional Properties.

    PubMed

    Hedayati, Mohammad Hossein; Norouzian, Dariush; Aminian, Mahdi; Teimourian, Shahram; Ahangari Cohan, Reza; Sardari, Soroush; Khorramizadeh, M Reza

    2017-02-01

    Erythropoietin (EPO) is the principal hormone which, has somewhat short half-life involved in the differentiation and regulation of circulating red blood cells. The present study was carried out to evaluate the capability of a polyethylene glycol mimetic technology as a biological alternative to improve pharmaceutical properties of human recombinant EPO. In silico models of EPO fused to 200 amino acids of proline, alanine, and serine (PAS) were initially generated and assessed by molecular dynamic (MD) simulation. The fluctuations of the modeled structure reached a plateau after 6000 ps of MD simulation. The Phi and psi analysis showed >99.2% of residues were located in the allowed regions. An expression vector consisting of EPO cDNA tagged to PAS coding sequences was synthesized and expressed in CHO-K1 Cells. The produced PASylated molecule was purified and characterized by standard analytical methods. The molecular weight of fusion protein was expanded to 70 kDa using sodium dodecyl sulfate polyacrylamide gel electrophoresis method. Analytical size exclusion chromatography revealed an approximately sevenfold increase in apparent size of produced protein. Although the in vitro potency of the fusion protein was significantly reduced (1.26 ± 0.05 vs. 0.24 ± 0.03 ng/ml) but, the in vivo activity was considerably increased up to 1.58 × 10(5) IU/ml in normocythemic mice assay. Pharmacokinetic animal studies revealed strongly 15.6-fold plasma half-life extension for the PASylated EPO (83.16 ± 13.28 h) in comparison to epoetin α (8.5 ± 2.4 h) and darbepoetin α (25.3 ± 2.2h).

  1. Cryopreservation of microencapsulated murine mesenchymal stem cells genetically engineered to secrete erythropoietin.

    PubMed

    Gurruchaga, Haritz; Ciriza, Jesús; Saenz Del Burgo, Laura; Rodriguez-Madoz, Juan Roberto; Santos, Edorta; Prosper, Felipe; Hernández, Rosa María; Orive, Gorka; Pedraz, Jose Luis

    2015-05-15

    The ability to cryopreserve and store for long term the structure and function of therapeutic cells and tissues plays a pivotal role in clinical medicine. In fact, it is an essential pre-requisite for the commercial and clinical application of stem cells since preserves cells at low temperature and creates a reserve for future uses. This requisite may also affect the encapsulated stem cells. Several parameters should be considered on encapsulated cell cryopreservation such as the time and temperature during the cryopreservation process, or the cryoprotectant solutions used. In this study, we have compared the influence of penetrating and nonpenetrating cryoprotectants on the viability and functionality of encapsulated mesenchymal stem cells genetically modified to secrete erythropoeitin. Several cryoprotectant solutions combining DMSO, glycerol and trehalose at different concentrations were studied. Although almost no differences among the studied cryoprotectant solutions were observed on the differentiation potential of encapsulated mesenchymal stem cells, the penetrating cryoprotectant DMSO at a concentration of 10% displayed the best viability and erythropoietin secretion profile compared to the other cryoprotectant solutions. These results were confirmed after subcutaneous implantation of thawed encapsulated mesenchymal stem cells secreting erythropoeitin on Balb/c mice. The hematocrit levels of these animals increased to similar levels of those detected on animals transplanted with noncryopreserved encapsulated cells. Therefore, DMSO 10% represents the most suitable cryoprotectant solution among the solutions here studied, for encapsulated mesenchymal stem cells cryopreservation and its translation into the clinic. Similar studies should be performed for the encapsulation of other cell types before they can be translated into the clinic.

  2. Neuroprotective effects of erythropoietin against oxidant injury following brain irradiation: an experimental study

    PubMed Central

    Cebi, Aysegul; Mert, Handan; Mert, Nihat; Serin, Meltem; Erkal, Haldun Sukru

    2016-01-01

    Introduction Radiation therapy (RT) is a major treatment modality, and the central nervous system is a dose-limiting organ in clinical RT. This experimental study aims to present the evaluation of the neuroprotective effects of erythropoietin (EPO) against oxidant injury following brain irradiation in rats. Material and methods Forty Wistar rats were randomly assigned to four groups (n = 10 each). In group 1 the rats received no EPO and underwent sham RT. The rats in groups 2 and 3 received EPO. In group 2 rats underwent sham RT, while in group 3 rats received RT. The rats in group 4 received no EPO and underwent RT. Rats were irradiated using a Cobalt-60 teletherapy machine using a single fraction of 20 Gy covering the whole brain. Cervical dislocation euthanasia was performed. The nitrite and malondialdehyde (MDA) levels and the superoxide dismutase (SOD) and glutathione peroxidase (GSHPX) activities were evaluated in dissected brain tissues. Results The nitrite and MDA levels were higher in the RT group (2.10 ±0.62 ppm, 26.02 ±2.16 nmol/ml; p < 0.05) and lower in the EPO + RT group (1.45 ±0.12 ppm, 25.49 ±1.90 nmol/ml; p < 0.05). The SOD and GSHPX activity was higher in the EPO + RT group (2.62 ±0.49 U/mg, 1.75 ±0.25 U/mg, p < 0.05). Conclusions This study supports the probable neuroprotective effects of EPO against oxidant injury following brain irradiation in a rat model, presumably through decreasing free radical production and increasing expression of antioxidant enzymes. PMID:27904528

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

    PubMed Central

    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; p<0.001). EPO increased phosphorylation (and presumed activation) of ERK (1.6 fold vs controls; p<0.05) in phrenic motor neurons; EPO also increased pAkt (1.6 fold vs controls; p<0.05). EPO-induced pMF was abolished by the MEK/ERK inhibitor U0126 and the PI3 kinase/Akt inhibitor LY294002, demonstrating that ERK MAP kinases and Akt are both required for EPO-induced pMF. Pre-treatment with U0126 and LY294002 decreased both pERK and pAkt in phrenic 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

  4. Mortality risk in hemodialysis patients according to anemia control and erythropoietin dosing.

    PubMed

    Santos, Paulo Roberto; Melo, Antonio Danilo Mourão; Lima, Monique Marie Brito Cortez; Negreiros, Idalina Maria A Holanda; Miranda, Jéssica Silva; Pontes, Larissa Salles; Rabelo, Guilherme Menezes; Viana, Ana Carolina Parente; Alexandrino, Mayara Teixeira; Barros, Francisco Anderson; Neto, Benjamin Ramos; Brito, Alana Alcântara; Da Silva Costa, Anderson

    2011-10-01

    There is no consensus about the toxicity of erythropoiesis-stimulating agents among hemodialysis patients. We aimed to calculate the risk of death according to anemia control and erythropoietin (EPO) dosing among end-stage renal disease patients undergoing hemodialysis. We retrospectively studied 156 end-stage renal disease patients on hemodialysis from a single renal unit during 12 months. Participants were classified according to anemia control into four groups: excellent (A), good (B), moderate (C) and bad (D) control. They were also classified according to EPO dosing into two groups: usual and high EPO dosing. The Cox proportional hazards regression model, adjusted for the difference in age, sex, time on dialysis, comorbidity, albumin, and Kt/V index, was performed to calculate the risk of death according to anemia control and EPO dosing profiles. Multivariate analysis by backward stepwise logistic regression was used to calculate the risk of death according to the variables that differed in the comparison between survivors and nonsurvivors. The hazard ratio of death was not significant according to anemia control profile C/D vs. A/B, but hazard ratio was 2.967 (95% confidence interval [CI] = 1.132-7.777; P = 0.027) for high EPO dosing profile patients. The multivariate analysis showed comorbidity (odds ratio [OR] = 8.958; 95% CI = 2.843-26.223; P < 0.001], high EPO dosing profile (OR = 5.172; 95% CI = 1.663-16,081; P = 0.005), age (OR = 1.056; 95% CI = 1.020-1.094; P = 0.002), and mean hemoglobin (OR = 0.435; 95% CI = 0.267-0.709; P = 0.001) to be predictive of death. Even though we cannot conclude that mortality risk is due to EPO toxicity, hemodialysis patients using high EPO dosing must be seen as at risk.

  5. Role of ATP-dependent K channels in the effects of erythropoietin in renal ischaemia injury

    PubMed Central

    Yilmaz, Tonguç Utku; Yazihan, Nuray; Dalgic, Aydın; Kaya, Ezgi Ermis; Salman, Bulent; Kocak, Mehtap; Akcil, Ethem

    2015-01-01

    Background & objectives: Erythropoietin (EPO) has cytoprotective and anti-apoptotic effects in pathological conditions, including hypoxia and ischaemia-reperfusion injury. One of the targets to protect against injury is ATP-dependent potassium (KATP) channels. These channels could be involved in EPO induced ischaemic preconditoning like a protective effect. We evaluated the cell cytoprotective effects of EPO in relation to KATP channel activation in the renal tubular cell culture model under hypoxic/normoxic conditions. Methods: Dose and time dependent effects of EPO, KATP channel blocker glibenclamide and KATP channel opener diazoxide on cellular proliferation were evaluated by colorimetric assay MTT [3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide] under normoxic and hypoxic conditions in human renal proximal tubular cell line (CRL-2830). Evaluation of the dose and time dependent effects of EPO, glibenclamide and diazoxide on apoptosis was done by caspase-3 activity levels. Hypoxia inducible factor-1 alpha (HIF-1 α) mRNA levels were measured by semi-quantative reverse transcription polymerase chain reaction (RT)-PCR. Kir 6.1 protein expresion was evalutaed by Western blot. Results: Glibenclamide treatment decreased the number of living cells in a time and dose dependent manner, whereas EPO and diazoxide treatments increased. Glibenclamide (100 μM) treatment significantly blocked the anti-apoptotic effects of EPO (10 IU/ml) under both normoxic and hypoxic conditions. EPO (10 IU/ml) and diazoxide (100 μM) treatments significantly increased (P<0.01) whereas glibenclamide decreased (P<0.05) HIF-1 α mRNA expression. Glibenclamide significantly (P<0.01) decreased EPO induced HIF-1 α mRNA expression when compared with the EPO alone group. Interpretation & conclusions: Our results showed that the cell proliferative, cytoprotective and anti-apoptotic effects of EPO were associated with KATP channels in the renal tubular cell culture model under hypoxic

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

    PubMed

    Yin, Bojiao; Gao, Yuan; Chung, Cheng-Yu; Yang, Shuang; Blake, Emily; Stuczynski, Mark C; Tang, Juechun; Kildegaard, Helene F; Andersen, Mikael R; Zhang, Hui; Betenbaugh, Michael J

    2015-11-01

    Sialic acid, a terminal residue on complex N-glycans, and branching or antennarity can play key roles in both the biological activity and circulatory lifetime of recombinant glycoproteins of therapeutic interest. In order to examine the impact of glycosyltransferase expression on the N-glycosylation of recombinant erythropoietin (rEPO), a human α2,6-sialyltransferase (ST6Gal1) was expressed in Chinese hamster ovary (CHO-K1) cells. Sialylation increased on both EPO and CHO cellular proteins as observed by SNA lectin analysis, and HPLC profiling revealed that the sialic acid content of total glycans on EPO increased by 26%. The increase in sialic acid content was further verified by detailed profiling of the N-glycan structures using mass spectra (MS) analysis. In order to enhance antennarity/branching, UDP-N-acetylglucosamine: α-1,3-D-mannoside β1,4-N-acetylglucosaminyltransferase (GnTIV/Mgat4) and UDP-N-acetylglucosamine:α-1,6-D-mannoside β1,6-N-acetylglucosaminyltransferase (GnTV/Mgat5), was incorporated into CHO-K1 together with ST6Gal1. Tri- and tetraantennary N-glycans represented approximately 92% of the total N-glycans on the resulting EPO as measured using MS analysis. Furthermore, sialic acid content of rEPO from these engineered cells was increased ∼45% higher with tetra-sialylation accounting for ∼10% of total sugar chains compared to ∼3% for the wild-type parental CHO-K1. In this way, coordinated overexpression of these three glycosyltransferases for the first time in model CHO-K1 cell lines provides a mean for enhancing both N-glycan branching complexity and sialylation with opportunities to generate tailored complex N-glycan structures on therapeutic glycoproteins in the future.

  7. Protective action of erythropoietin on neuronal damage induced by activated microglia.

    PubMed

    Wenker, Shirley D; Chamorro, María E; Vittori, Daniela C; Nesse, Alcira B

    2013-04-01

    Inflammation is a physiological defense response, but may also represent a potential pathological process in neurological diseases. In this regard, microglia have a crucial role in either progression or amelioration of degenerative neuronal damage. Because of the role of hypoxia in pro-inflammatory mechanisms in the nervous system, and the potential anti-inflammatory protective effect of erythropoietin (Epo), we focused our investigation on the role of this factor on activation of microglia and neuroprotection. Activation of microglial cells (EOC-2) was achieved by chemical hypoxia induced by cobalt chloride (CoCl2 ) and characterized by increased levels of nitrite, tumor necrosis factor-α and reactive oxygen species production, as well as up-regulation of inducible nitric oxide synthase expression. Under these conditions, cell proliferation data and proliferating cell nuclear antigen (PCNA) staining demonstrated a mitogenic effect of chemical hypoxia. Even though pre-treatment with Epo did not prevent nitrite production, inducible nitric oxide synthase protein expression or tumor necrosis factor-α secretion, it prevented the oxidative stress induced by CoCl2 as well as cell proliferation. Neuronal cells (SH-SY5Y) cultured in the presence of conditioned medium from activated EOC-2 cells or macrophages (RAW 264.7) developed significant apoptosis, an effect that was abolished by Epo via Epo/Epo receptor activation. The results show that even though Epo did not exert a direct anti-inflammatory effect on microglia activation, it did increase the resistance of neurons to subsequent damage from pro-inflammatory agents. In addition to its anti-apoptotic ability, the Epo antioxidant effect may have an indirect influence on neuronal survival by modulation of the pro-inflammatory environment.

  8. Doping with growth hormone/IGF-1, anabolic steroids or erythropoietin: is there a cancer risk?

    PubMed

    Tentori, Lucio; Graziani, Grazia

    2007-05-01

    Anabolic steroid and peptide hormones or growth factors are utilized to increase the performance of athletes of professional or amateur sports. Despite their well-documented adverse effects, the use of some of these agents has significantly grown and has been extended also to non-athletes with the aim to improve appearance or to counteract ageing. Pre-clinical studies and epidemiological observations in patients with an excess of hormone production or in patients chronically treated with hormones/growth factors for various pathologies have warned about the potential risk of cancer development and progression which may be also associated to the use of certain doping agents. Anabolic steroids have been described to provoke liver tumours; growth hormone or high levels of its mediator insulin-like growth factor-1 (IGF-1) have been associated with colon, breast, and prostate cancers. Actually, IGF-1 promotes cell cycle progression and inhibits apoptosis either by triggering other growth factors or by interacting with pathways which have an established role in carcinogenesis and cancer promotion. More recently, the finding that erythropoietin (Epo) may promote angiogenesis and inhibit apoptosis or modulate chemo- or radiosensitivity in cancer cells expressing the Epo receptor, raised the concern that the use of recombinant Epo to increase tissue oxygenation might favour tumour survival and aggressiveness. Cancer risk associated to doping might be higher than that of patients using hormones/growth factors as replacement therapy, since enormous doses are taken by the athletes often for a long period of time. Moreover, these substances are often used in combination with other licit or illicit drugs and this renders almost unpredictable all the possible adverse effects including cancer. Anyway, athletes should be made aware that long-term treatment with doping agents might increase the risk of developing cancer.

  9. Erythrocyte incorporation and absorption of 58Fe in premature infants treated with erythropoietin.

    PubMed

    Widness, J A; Lombard, K A; Ziegler, E E; Serfass, R E; Carlson, S J; Johnson, K J; Miller, J E

    1997-03-01

    We hypothesized that treatment of very low birth weight premature infants with r-HuEPO would increase erythrocyte incorporation and gastrointestinal absorption of iron. Infants with birth weights < or = 1.25 kg and gestational ages < 31 wk were randomized to receive 6 wk of 500 U of r-HuEPO/kg/wk (epo group, n = 7) or placebo (placebo group, n = 7). All infants received daily enteral supplementation with 6 mg of elemental iron per kg. An enteral test dose of a stable iron isotope, 58Fe, was administered after the 1st ("early dosing") and 4th ("late dosing") wk of treatment. Mean (+/-SD) erythrocyte incorporation of the dose of 58Fe administered determined 2 wk after early dosing was significantly greater in the epo group compared with the placebo group (4.4% +/- 1.6 versus 2.0 +/- 1.4%, p = 0.013). In contrast, after late 58Fe dosing, there was no difference between groups in incorporation (3.8 +/- 1.6% versus 5.5 +/- 2.7%). Within the epo group, percentage erythrocyte incorporation of 58Fe did not differ between early and late dosing, whereas in the placebo group it increased 3-fold (p < 0.01). Percentage absorption of 58Fe was not different between the epo and placebo groups after both early dosing (30 +/- 22% versus 34 +/- 8%) and late dosing (32 +/- 9% versus 31 +/- 6%). Absorption of nonlabeled elemental iron and 58Fe were significantly correlated with one another. The percentage of the absorbed 58Fe dose incorporated into Hb was not different between groups. We conclude that, although erythropoietin treatment stimulates erythrocyte iron incorporation in premature infants, it has no effect on iron absorption at the r-HuEPO dose studied.

  10. Erythropoietin doping in cycling: lack of evidence for efficacy and a negative risk–benefit

    PubMed Central

    Heuberger, Jules A A C; Cohen Tervaert, Joost M; Schepers, Femke M L; Vliegenthart, Adriaan D B; Rotmans, Joris I; Daniels, Johannes M A; Burggraaf, Jacobus; Cohen, Adam F

    2013-01-01

    Imagine a medicine that is expected to have very limited effects based upon knowledge of its pharmacology and (patho)physiology and that is studied in the wrong population, with low-quality studies that use a surrogate end-point that relates to the clinical end-point in a partial manner at most. Such a medicine would surely not be recommended. The use of recombinant human erythropoietin (rHuEPO) to enhance performance in cycling is very common. A qualitative systematic review of the available literature was performed to examine the evidence for the ergogenic properties of this drug, which is normally used to treat anaemia in chronic renal failure patients. The results of this literature search show that there is no scientific basis from which to conclude that rHuEPO has performance-enhancing properties in elite cyclists. The reported studies have many shortcomings regarding translation of the results to professional cycling endurance performance. Additionally, the possibly harmful side-effects have not been adequately researched for this population but appear to be worrying, at least. The use of rHuEPO in cycling is rife but scientifically unsupported by evidence, and its use in sports is medical malpractice. What its use would have been, if the involved team physicians had been trained in clinical pharmacology and had investigated this properly, remains a matter of speculation. A single well-controlled trial in athletes in real-life circumstances would give a better indication of the real advantages and risk factors of rHuEPO use, but it would be an oversimplification to suggest that this would eradicate its use. PMID:23216370

  11. Effect of fiber length of carbon nanotubes on the absorption of erythropoietin from rat small intestine.

    PubMed

    Ito, Yukako; Venkatesan, Natarajan; Hirako, Noriko; Sugioka, Nobuyuki; Takada, Kanji

    2007-06-07

    Erythropoietin (EPO) loaded carbon nanotubes (CNTs) with surfactant as an absorption enhancer were prepared for the oral delivery of EPO using two types of CNTs, long and short fiber length CNTs, and the effect of CNT fiber length on the absorption efficiency of EPO was studied. After Labrasol, PEG-8 caprylic/capric glycerides, as absorption enhancer was adsorbed into long fiber CNTs of which mean fiber length was 20-80 microm, as a carrier, EPO and casein as protease inhibitor and Explotab (sodium starch glycolate) as a disintegrating agent, were mixed. The resulting solid preparation was administered into the rat jejunum and serum EPO levels were measured by ELISA. The dose of EPO, CNTs, casein and Explotab were 100 IU/kg, 5mg/kg, 25mg/kg and 2.5mg/kg, respectively. Serum EPO level reached to C(max), 69.0+/-3.9 mIU/ml, at 3.5+/-0.1h and AUC was 175.7+/-13.8 mIU h/ml. These values were approximately half of that obtained with short fiber length CNTs of which C(max) was 143.1+/-15.2 mIU/ml and AUC was 256.3+/-9.7 mIU h/ml. When amphoteric surfactant, Lipomin LA, sodium beta-alkylaminopropionic acid, was used to accelerate the disaggregation of long fiber length CNTs, C(max) was 36.0+/-4.9 and AUC was 96.9+/-11.9, which showed less bioavailability (BA) of EPO. These results suggest that the short fiber length CNTs deliver more both EPO and absorption enhancer to the absorptive cells of the rat small intestine and the aggregation of CNTs is not the critical factor for the oral delivery of EPO.

  12. [Treatment of anemia in hemodialysis patients using recombinant human erythropoietin: advantages and disadvantages].

    PubMed

    Zehnder, C; Blumberg, A

    1989-03-04

    18 anemic patients undergoing maintenance hemodialysis were treated with recombinant human erythropoietin (EPO) 1-3 times per week for 10.7 +/- 3 months. 4 patients underwent renal transplantation whereas 14 patients could be followed up during 12 months of EPO treatment. Hemoglobin concentration rose (from 7.0 +/- 0.7 to 11.0 +/- 1.1 g/dl, p less than 0.001) with an EPO maintenance dose of 298 units/kg/week. Blood transfusions were totally eliminated. 12 patients without iron overload required iron supplements. In the course of an infectious episode and notwithstanding an increase in EPO dosage, 2 patients exhibited a fall in hemoglobin which rose again after successful treatment of the infection. The few complications observed in connection with the rise in hemoglobin were: 1. deterioration of arterial hypertension in 7/18 with hypertensive encephalopathy in 3 patients, 2. thrombotic occlusion of the vascular hemodialysis access (a-v fistula) in 3/18, 3. periarticular inflammation with calcified deposits due to an elevated calcium-phosphorus product of 6.8 mmol/l in 4/18, 4. occurrence of hyperkalemia (6.9 +/- 0.3 mmol/l) in 7/18. These complications were more frequent during the first 3 months. They were corrected with close monitoring, drug therapy for hypertension, and intensification of dialysis and of treatment with phosphate binding substances, with the result that no differences were found in 14 patients before and after 12 months of treatment with EPO (blood pressure 133 +/- 25/77 +/- 9 vs 139 +/- 26/79 +/- 13 mm Hg [ns], potassium 5.4 +/- 0.4 vs 5.6 +/- 1.0 mmol/l [ns] and calcium-phosphorus product 4.3 +/- 1.0 vs 4.6 +/- 1.3 [ns]).(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Erythropoietin promotes neurovascular remodeling and long-term functional recovery in rats following traumatic brain injury.

    PubMed

    Ning, Ruizhuo; Xiong, Ye; Mahmood, Asim; Zhang, Yanlu; Meng, Yuling; Qu, Changsheng; Chopp, Michael

    2011-04-12

    Erythropoietin (EPO) improves functional recovery after traumatic brain injury (TBI). This study was designed to investigate long-term (3 months) effects of EPO on brain remodeling and functional recovery in rats after TBI. Young male Wistar rats were subjected to unilateral controlled cortical impact injury. TBI rats were divided into the following groups: (1) saline group (n=7); (2) EPO-6h group (n=8); and (3) EPO-24h group (n=8). EPO (5000 U/kg in saline) was administered intraperitoneally at 6h, and 1 and 2 days (EPO-6h group) or at 1, 2, and 3 days (EPO-24h group) postinjury. Neurological function was assessed using a modified neurological severity score, footfault and Morris water maze tests. Animals were sacrificed at 3 months after injury and brain sections were stained for immunohistochemical analyses. Compared to the saline, EPO-6h treatment significantly reduced cortical lesion volume, while EPO-24h therapy did not affect the lesion volume (P<0.05). Both the EPO-6h and EPO-24h treatments significantly reduced hippocampal cell loss (P<0.05), promoted angiogenesis (P<0.05) and increased endogenous cellular proliferation (BrdU-positive cells) in the injury boundary zone and hippocampus (P<0.05) compared to saline controls. Significantly enhanced neurogenesis (BrdU/NeuN-positive cells) was seen in the dentate gyrus of both EPO groups compared to the saline group. Both EPO treatments significantly improved long-term sensorimotor and cognitive functional recovery after TBI. In conclusion, the beneficial effects of posttraumatic EPO treatment on injured brain persisted for at least 3 months. The long-term improvement in functional outcome may in part be related to the neurovascular remodeling induced by EPO.

  14. Recovery of motor spontaneous activity after intranasal delivery of human recombinant erythropoietin in a focal brain hypoxia model induced by CoCl2 in rats.

    PubMed

    Merelli, Amalia; Caltana, Laura; Girimonti, Patricia; Ramos, Alberto Javier; Lazarowski, Alberto; Brusco, Alicia

    2011-08-01

    Stroke is a major human health problem inducing long-term disability without any efficient therapeutic option being currently available. Under hypoxia, hypoxia-inducible factor-1α (HIF-1α) activates several genes as erythropoietin receptor (Epo-R) related with O(2) supply, and the multidrug-resistance gene (MDR-1) related with drug-refractory phenotype. Brain cortical injection of CoCl(2) produces focal hypoxia-like lesion with neuronal and glial alterations, as well as HIF-1α stabilization and MDR-1 overexpression. Intranasal (IN) drug delivery can by-pass blood-brain barrier (BBB) where MDR-1 is normally expressed. We evaluated the effects of IN-rHu-Epo administration on spontaneous motor activity (SMA) and the brain pattern expression of HIF-1α, MDR-1, and Epo-R in our cobalt-induced hypoxia model. Adult male Wistar rats were injected by stereotaxic surgery in frontoparietal cortex, with CoCl(2) (2 μl-50 mM; n = 20) or saline (controls; n = 20). Ten rats of each group were treated with IN-rHu-Epo 24 U or IN-saline. In addition, erythropoietic stimulation was evaluated by reticulocytes (Ret) account during three consecutive days, after intraperitoneal (i.p.)-recombinant-human Epo (rHu-Epo) (950 U; n = 6) or IN-rHu-Epo (24 U; n = 6) administration. SMA was evaluated by open field and rotarod tests, before and after surgical procedures during five consecutive days. Histological and immunostaining studies of HIF-1α, MDR-1, and Epo-R were performed on brain slides. A significant difference in SMA was observed in the hypoxic rats of IN-rHu-Epo-administered group as compared with Co-Saline-treated subjects and controls (p < 0.001). HIF-1α, EPO-R, and MDR-1 were overexpressed in the hypoxic cortex areas, while in contralateral hemisphere or controls, they were negatives. Reticulocytes were only increased in intraperitoneal (i.p.)-rHu-Epo-administered group. In spite of MDR-1 overexpression being detected in neurons, the coexpression of Epo-R could

  15. Paine Appointed Administrator

    NASA Technical Reports Server (NTRS)

    1969-01-01

    President Richard M. Nixon announcing the appointment of Dr. Thomas O. Paine as Administrator for the National Aeronautics and Space Administration. The ceremony was held at the White House. Paine had been serving as acting administrator. From left to right: President Richard M. Nixon NASA Administrator Dr. Thomas O. Paine Vice President Spiro T. Agnew

  16. Predicting erythroid response to recombinant erythropoietin plus granulocyte colony-stimulating factor therapy following a single subcutaneous bolus in patients with myelodysplasia.

    PubMed

    Bowen, David; Hyslop, Ann; Keenan, Norene; Groves, Michael; Culligan, Dominic; Johnson, Peter; Shaw, Ann; Geddes, Fiona; Evans, Patricia; Porter, John; Cavill, Ivor

    2006-05-01

    We randomized 21 patients with low-risk myelodysplastic syndromes (MDS) to receive a single subcutaneous bolus of recombinant erythropoietin (epoietin) +/- granulocyte-colony stimulating factor (G-CSF), or placebo and monitored erythropoietic response over 7 days. In this small study, the reticulocyte response at day 7 was highly predictive of subsequent response to a therapeutic trial of epoietin + G-CSF.

  17. EPOR-Based Purification and Analysis of Erythropoietin Mimetic Peptides from Human Urine by Cys-Specific Cleavage and LC/MS/MS

    NASA Astrophysics Data System (ADS)

    Vogel, Matthias; Thomas, Andreas; Schänzer, Wilhelm; Thevis, Mario

    2015-09-01

    The development of a new class of erythropoietin mimetic agents (EMA) for treating anemic conditions has been initiated with the discovery of oligopeptides capable of dimerizing the erythropoietin (EPO) receptor and thus stimulating erythropoiesis. The most promising amino acid sequences have been mounted on various different polymeric structures or carrier molecules to obtain highly active EPO-like drugs exhibiting beneficial and desirable pharmacokinetic profiles. Concomitant with creating new therapeutic options, erythropoietin mimetic peptide (EMP)-based drug candidates represent means to artificially enhance endurance performance and necessitate coverage by sports drug testing methods. Therefore, the aim of the present study was to develop a strategy for the comprehensive detection of EMPs in doping controls, which can be used complementary to existing protocols. Three model EMPs were used to provide proof-of-concept data. Following EPO receptor-facilitated purification of target analytes from human urine, the common presence of the cysteine-flanked core structure of EMPs was exploited to generate diagnostic peptides with the aid of a nonenzymatic cleavage procedure. Sensitive detection was accomplished by targeted-SIM/data-dependent MS2 analysis. Method characterization was conducted for the EMP-based drug peginesatide concerning specificity, linearity, precision, recovery, stability, ion suppression/enhancement, and limit of detection (LOD, 0.25 ng/mL). Additionally, first data for the identification of the erythropoietin mimetic peptides EMP1 and BB68 were generated, demonstrating the multi-analyte testing capability of the presented approach.

  18. Far-western blotting as a solution to the non-specificity of the anti-erythropoietin receptor antibody

    PubMed Central

    Fecková, Barbora; Kimáková, Patrícia; Ilkovičová, Lenka; Szentpéteriová, Erika; Debeljak, Nataša; Solárová, Zuzana; Sačková, Veronika; Šemeláková, Martina; Bhide, Mangesh; Solár, Peter

    2016-01-01

    The erythropoietin receptor (EpoR) is a member of the cytokine receptor family. The interaction between erythropoietin (Epo) and EpoR is important for the production and maturation of erythroid cells, resulting in the stimulation of hematopoiesis. The fact that EpoR was also detected in neoplastic cells has opened the question about the relevance of anemia treatment with recombinant Epo in cancer patients. Numerous studies have reported pro-stimulating and anti-apoptotic effects of Epo in cancer cells, thus demonstrating EpoR functionality in these cells. By contrast, a previous study claims the absence of EpoR in tumor cells. This apparent discrepancy is based, according to certain authors, on the use of non-specific anti-EpoR antibodies. With the aim of bypassing the direct detection of EpoR with an anti-EpoR antibody, the present authors propose a far-western blot methodology, which in addition, confirms the interaction of Epo with EpoR. Applying this technique, the presence of EpoR and its interaction with Epo in human ovarian adenocarcinoma A2780 and normal human umbilical vein endothelial cells was confirmed. Furthermore, modified immunoprecipitation of EpoR followed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry analysis confirmed a 57 kDa protein as a human Epo-interacting protein in both cell lines. PMID:27446474

  19. The inhibition of postinfarct ventricle remodeling without polycythaemia following local sustained intramyocardial delivery of erythropoietin within a supramolecular hydrogel.

    PubMed

    Wang, Tao; Jiang, Xue-Jun; Lin, Tao; Ren, Shan; Li, Xiao-Yan; Zhang, Xian-Zheng; Tang, Qi-zhu

    2009-09-01

    Erythropoietin (EPO) can protect myocardium from ischemic injury, but it also plays an important role in promoting polycythaemia, the potential for thrombo-embolic complications. Local sustained delivery of bioactive agents directly to impaired tissues using biomaterials is an approach to limit systemic toxicity and improve the efficacy of therapies. The present study was performed to investigate whether local intramyocardial injection of EPO with hydrogel could enhance cardioprotective effect without causing polycythaemia after myocardial infarction (MI). To test the hypothesis, phosphate buffered solution (PBS), alpha-cyclodextrin/MPEG-PCL-MPEG hydrogel, recombined human erythropoietin (rhEPO) in PBS, or rhEPO in hydrogel were injected into the infarcted area immediately after MI in rats. The hydrogel allowed a sustained release of EPO, which inhibited cell apoptosis and increased neovasculature formation, and subsequently reduced infarct size and improved cardiac function compared with other groups. Notably, there was no evidence of polycythaemia from this therapy, with no differences in erythrocyte count and hematocrit compared with the animals received PBS or hydrogel blank injection. In conclusion, intramyocardial delivery of rhEPO with alpha-cyclodextrin/MPEG-PCL-MPEG hydrogel may lead to cardiac performance improvement after MI without apparent adverse effect.

  20. Erythropoietin-induced progenitor cell mobilisation in patients with acute ST-segment-elevation myocardial infarction and restenosis.

    PubMed

    Stein, A; Mohr, F; Laux, M; Thieme, S; Lorenz, B; Cetindis, M; Hackl, J; Groha, P; Demetz, G; Schulz, S; Mehilli, J; Schömig, A; Kastrati, A; Ott, I

    2012-04-01

    Erythropoietin improves myocardial function and enhances re-endothelialisation. Aim of this study was to analyse progenitor cell mobilisation and restenosis in patients from the Regeneration of Vital Myocardium in ST-Segment Elevation Myocardial Infarction by Erythropoietin (REVIVAL-3) study. Patients with STEMI undergoing percutaneous coronary intervention (PCI) were randomly assigned to Epoetin beta (EPO) (n=68) or placebo (n=70). Drug-eluting stents (DES) were utilised in 93% of patients receiving EPO and in 95% of patients receiving placebo (p=0.83). Serial venous blood samples were drawn; CD133+ progenitor cells were quantified by four-colour flow cytometry and cytokines interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-12 and tumour necrosis factor (TNF) alpha were analysed by cytometric bead array. Forty-eight hours after PCI a significant increase in CD133+ progenitor cells was observed in the EPO group. Yet, no differences in plasma cytokines were found. Quantitative coronary angiography after six months revealed an increase in segment diameter stenosis in the EPO group (32 ± 19% vs. 26 ± 14%, p=0.046). However, this increase in neointima generation was not associated with progenitor cell mobilisation. EPO in patients with STEMI treated with PCI is associated with an increase in diameter stenosis that is not associated with circulating progenitor cells.

  1. Methylation impact analysis of erythropoietin (EPO) Gene to hypoxia inducible factor-1α (HIF-1α) activity.

    PubMed

    Dewi, Firli Rahmah Primula; Fatchiyah, Fatchiyah

    2013-01-01

    Erythropoietin (EPO) is a glycoprotein hormone that play a role as key regulator in the production of red blood cells. The promoter region of EPO is methylated in normoxic (non-hypoxia) condition, but not in hypoxic condition. Methylation of the EPO enhancer region decline the transcription activity of EPO gene. The aim of this study is to investigate how different methylation percentage affected on the regulation and transcriptional activity of EPO gene. The DNA sequence of erythropoietin gene and protein sequence was retrieved from the sequence database of NCBI. DNA structure was constructed using 3D-DART web server and modeling structure of HIF1 predicted using SWISS-MODEL web server. Methylated DNA sequence of EPO gene using performed with YASARA View software and docking of EPO gene and transcription factor HIF1 analyzed by using HADDOCK webserver. Our result showed that binding energy in 46% methylated DNA was higher (-161,45 kcal/mol) than in unmethylated DNA (-194,16 kcal/mol) and 8% methylated DNA (-175,94 kcal/mol). So, we presume that a silencing mechanism of the Epo gene by methylation is correlated with the binding energy, which is required for interaction. A higher methylation percentage correlates with a higher binding energy which can cause an unstable interaction between DNA and transcription factor. In conclution, methylation of promoter and enhancer region of Epo gene leads to silencing.

  2. Total saponins of Panax ginseng induces K562 cell differentiation by promoting internalization of the erythropoietin receptor.

    PubMed

    Zuo, Guowei; Guan, Tao; Chen, Dilong; Li, Chunli; Jiang, Rong; Luo, Chunyan; Hu, Xiaoshu; Wang, Yaping; Wang, Jianwei

    2009-01-01

    Ginseng is a commonly used herbal medicine with a wide range of therapeutic benefits. Total saponins of Panax ginseng (TSPG) is one of the main effective components of ginseng. Our previous studies have shown that TSPG could promote the production of normal blood cells and inhibition of the leukemia cell proliferation. However, whether ginseng can induce the differentiation of leukemia cells is still unclear. This study was to examine the effect of TSPG or the combination of erythropoietin (EPO) and TSPG on the erythroid differentiation of K562 cells, and their corresponding mechanisms regarding erythropoietin receptor (EPOR) expression. Under light and electron microscopes, the TSPG- or TSPG + EPO-treated K562 cells showed a tendency to undergo erythroid differentiation; early and intermediate erythroblast-like cells were observed. Hemoglobin and HIR2 expressions were significantly increased. As determined by Western blotting analysis, the EPOR protein level in the K562 cytoplasmic membrane was significantly decreased after TSPG treatment, while its cytoplasm level increased in a dose-dependent manner. However, the total cellular EPOR level was unchanged. These results indicate that TSPG-induced erythroid differentiation of K562 cells may be accompanied by the internalization of EPOR. Thus, our study suggests that treatment with a combination of TSPG and EPO may induce erythroid differentiation of K562 cells at least in part through induction of EPOR internalization.

  3. Inactivation of erythropoietin receptor function by point mutations in a region having homology with other cytokine receptors.

    PubMed Central

    Miura, O; Cleveland, J L; Ihle, J N

    1993-01-01

    The cytoplasmic domain of the erythropoietin receptor (EpoR) contains a region, proximal to the transmembrane domain, that is essential for function and has homology with other members of the cytokine receptor family. To explore the functional significance of this region and to identify critical residues, we introduced several amino acid substitutions and examined their effects on erythropoietin-induced mitogenesis, tyrosine phosphorylation, and expression of immediate-early (c-fos, c-myc, and egr-1) and early (ornithine decarboxylase and T-cell receptor gamma) genes in interleukin-3-dependent cell lines. Amino acid substitution of W-282, which is strictly conserved at the middle portion of the homology region, completely abolished all the functions of the EpoR. Point mutation at L-306 or E-307, both of which are in a conserved LEVL motif, drastically impaired the function of the receptor in all assays. Other point mutations, introduced into less conserved amino acid residues, did not significantly impair the function of the receptor. These results demonstrate that conserved amino acid residues in this domain of the EpoR are required for mitogenesis, stimulation of tyrosine phosphorylation, and induction of immediate-early and early genes. Images PMID:8382775

  4. Skeletal muscle alterations and exercise performance decrease in erythropoietin-deficient mice: a comparative study

    PubMed Central

    2012-01-01

    Background Erythropoietin (EPO) is known to improve exercise performance by increasing oxygen blood transport and thus inducing a higher maximum oxygen uptake (VO2max). Furthermore, treatment with (or overexpression of) EPO induces protective effects in several tissues, including the myocardium. However, it is not known whether EPO exerts this protective effect when present at physiological levels. Given that EPO receptors have been identified in skeletal muscle, we hypothesized that EPO may have a direct, protective effect on this tissue. Thus, the objectives of the present study were to confirm a decrease in exercise performance and highlight muscle transcriptome alterations in a murine EPO functional knock-out model (the EPO-d mouse). Methods We determined VO2max peak velocity and critical speed in exhaustive runs in 17 mice (9 EPO-d animals and 8 inbred controls), using treadmill enclosed in a metabolic chamber. Mice were sacrificed 24h after a last exhaustive treadmill exercise at critical speed. The tibialis anterior and soleus muscles were removed and total RNA was extracted for microarray gene expression analysis. Results The EPO-d mice’s hematocrit was about 50% lower than that of controls (p < 0.05) and their performance level was about 25% lower (p < 0.001). A total of 1583 genes exhibited significant changes in their expression levels. However, 68 genes were strongly up-regulated (normalized ratio > 1.4) and 115 were strongly down-regulated (normalized ratio < 0.80). The transcriptome data mining analysis showed that the exercise in the EPO-d mice induced muscle hypoxia, oxidative stress and proteolysis associated with energy pathway disruptions in glycolysis and mitochondrial oxidative phosphorylation. Conclusions Our results showed that the lack of functional EPO induced a decrease in the aerobic exercise capacity. This decrease was correlated with the hematocrit and reflecting poor oxygen supply to the muscles. The observed

  5. A radioimmunoassay for erythropoietin: serum levels in normal human subjects and patients with hemopoietic disorders

    SciTech Connect

    Rege, A.B.; Brookins, J.; Fisher, J.W.

    1982-12-01

    An RIA for Ep has been developed that is highly sensitive and specific. A homogeneous Ep preparation was labeled with /sup 125/I by the chloramine-T method to a specific activity of 90 to 136 ..mu..Ci/..mu..g and immunoreactivity of 80%. Ep antiserum, which was produced to a human urinary Ep preparation (80 U/mg of protein), was adsorbed with normal human urinary and serum proteins without any loss in sensitivity of the RIA to increase the specificity of the assay. A good correlation was seen between the RIA and the exhypoxic polycythemic mouse assay (corr. coef. 0.967; slope 1.05 and ''y'' intercept 0.75). Ep titers in sera from 175 hematologically normal human subjects exhibited a normal frequency distribution and ranged between 5.8 and 36.6 mU/ml with a mean of 14.9 +/- 4.7 (S.D.) and median of 14.3. Serum Ep titers were markedly elevated in seven patients with aplastic anemia and one patient with pure red cell aplasia (1350 to 20,640 mU/ml) and were lower than normal in two patients with polycythemia vera (8.1 and 9.4 mU/ml). The serum Ep titers in a prenephrectomy patient with chronic glomerulonephritis (31.1 mU/ml) decreased to below normal levels (9.04 mU/ml) after nephrectomy. The cord serum erythropoietin titers in 10 IDM (90.82 +/- 134.1 (S.D.) mu/ml) returned to values within the normal range (13.86 +/- 5.55) on day 3 after birth, suggesting the utility of the RIA in elucidating the role of hypoxia and/or insulin in increased erythropoiesis in IDM. The serum Ep titers in patients with anemias and polycythemias were compared to those of normal human subjects and agreed well with pathophysiologic mechanisms of these hemopoietic disorders, confirming the validity of the RIA.

  6. A radioimmunoassay for erythropoietin: serum levels in normal human subjects and patients with hemopoietic disorders

    SciTech Connect

    Rege, A.B.; Brookins, J.; Fisher, J.W.

    1982-12-01

    An RIA for Ep has been developed that is highly sensitive and specific. A homogeneous Ep preparation was labeled with /sup 125/I by the chloramine-T method to a specific activity of 90 to 136 micro Ci/microgram and immunoreactivity of 80%. Ep antiserum, which was produced to a human urinary Ep preparation (80 U/mg of protein), was adsorbed with normal human urinary and serum proteins without any loss in sensitivity of the RIA to increase the specificity of the assay. A good correlation was seen between the RIA and the exhypoxic polycythemic mouse assay (corr. coef. 0.967; slope 1.05 and y intercept 0.75). Ep titers in sera from 175 hematologically normal human subjects exhibited a normal frequency distribution and ranged between 5.8 and 36.6 mU/ml with a mean of 14.9 +/- 4.7 (S.D.) and median of 14.3 Serum Ep titers were markedly elevated in seven patients with aplastic anemia and one patient with pure red cell aplasia (1350 to 20,640 mU/ml) and were lower than normal in two patients with polycythemia vera (8.1 and 9.4 mU/ml). The serum Ep titers in a prenephrectomy patient with chronic glomerulonephritis (32.1 mU/ml) decreased to below normal levels (9.04 mU/ml) after nephrectomy. The cord serum erythropoietin titers in 10 IDM (90.82 +/- 134.1 (S.D.) mu/ml) returned to values within the normal range (13.86 +/- 5.55) on day 3 after birth, suggesting the utility of the RIA in elucidating the role of hypoxia and/or insulin in increased erythropoiesis in IDM. The serum Ep titers in patients with anemias and polycythemias were compared to those of normal human subjects and agreed well with pathophysiologic mechanisms of these hemopoietic disorders, confirming the validity of the RIA.

  7. Determinants of erythropoietin release in response to short-term hypobaric hypoxia

    NASA Technical Reports Server (NTRS)

    Ge, Ri-Li; Witkowski, S.; Zhang, Y.; Alfrey, C.; Sivieri, M.; Karlsen, T.; Resaland, G. K.; Harber, M.; Stray-Gundersen, J.; Levine, B. D.

    2002-01-01

    We measured blood erythropoietin (EPO) concentration, arterial O(2) saturation (Sa(O(2))), and urine PO(2) in 48 subjects (32 men and 16 women) at sea level and after 6 and 24 h at simulated altitudes of 1,780, 2,085, 2,454, and 2,800 m. Renal blood flow (Doppler) and Hb were determined at sea level and after 6 h at each altitude (n = 24) to calculate renal O(2) delivery. EPO increased significantly after 6 h at all altitudes and continued to increase after 24 h at 2,454 and 2,800 m, although not at 1,780 or 2,085 m. The increase in EPO varied markedly among individuals, ranging from -41 to 400% after 24 h at 2,800 m. Similar to EPO, urine PO(2) decreased after 6 h at all altitudes and returned to baseline by 24 h at the two lowest altitudes but remained decreased at the two highest altitudes. Urine PO(2) was closely related to EPO via a curvilinear relationship (r(2) = 0.99), although also with prominent individual variability. Renal blood flow remained unchanged at all altitudes. Sa(O(2)) decreased slightly after 6 h at the lowest altitudes but decreased more prominently at the highest altitudes. There were only modest, albeit statistically significant, relationships between EPO and Sa(O(2)) (r = 0.41, P < 0.05) and no significant relationship with renal O(2) delivery. These data suggest that 1) the altitude-induced increase in EPO is "dose" dependent: altitudes > or =2,100-2,500 m appear to be a threshold for stimulating sustained EPO release in most subjects; 2) short-term acclimatization may restore renal tissue oxygenation and restrain the rise in EPO at the lowest altitudes; and 3) there is marked individual variability in the erythropoietic response to altitude that is only partially explained by "upstream" physiological factors such as those reflecting O(2) delivery to EPO-producing tissues.

  8. Erythropoietin in amyotrophic lateral sclerosis: a multicentre, randomised, double blind, placebo controlled, phase III study

    PubMed Central

    Lauria, Giuseppe; Dalla Bella, Eleonora; Antonini, Giovanni; Borghero, Giuseppe; Capasso, Margherita; Caponnetto, Claudia; Chiò, Adriano; Corbo, Massimo; Eleopra, Roberto; Fazio, Raffaella; Filosto, Massimiliano; Giannini, Fabio; Granieri, Enrico; La Bella, Vincenzo; Logroscino, Giancarlo; Mandrioli, Jessica; Mazzini, Letizia; Monsurrò, Maria Rosaria; Mora, Gabriele; Pietrini, Vladimiro; Quatrale, Rocco; Rizzi, Romana; Salvi, Fabrizio; Siciliano, Gabriele; Sorarù, Gianni; Volanti, Paolo; Tramacere, Irene; Filippini, Graziella

    2015-01-01

    Objective To assess the efficacy of recombinant human erythropoietin (rhEPO) in amyotrophic lateral sclerosis (ALS). Methods Patients with probable laboratory-supported, probable or definite ALS were enrolled by 25 Italian centres and randomly assigned (1:1) to receive intravenous rhEPO 40 000 IU or placebo fortnightly as add-on treatment to riluzole 100 mg daily for 12 months. The primary composite outcome was survival, tracheotomy or >23 h non-invasive ventilation (NIV). Secondary outcomes were ALSFRS-R, slow vital capacity (sVC) and quality of life (ALSAQ-40) decline. Tolerability was evaluated analysing adverse events (AEs) causing withdrawal. The randomisation sequence was computer-generated by blocks, stratified by centre, disease severity (ALSFRS-R cut-off score of 33) and onset (spinal or bulbar). The main outcome analysis was performed in all randomised patients and by intention-to-treat for the entire population and patients stratified by severity and onset. The study is registered, EudraCT 2009-016066-91. Results We randomly assigned 208 patients, of whom 5 (1 rhEPO and 4 placebo) withdrew consent and 3 (placebo) became ineligible (retinal thrombosis, respiratory insufficiency, SOD1 mutation) before receiving treatment; 103 receiving rhEPO and 97 placebo were eligible for analysis. At 12 months, the annualised rate of death (rhEPO 0.11, 95% CI 0.06 to 0.20; placebo: 0.08, CI 0.04 to 0.17), tracheotomy or >23 h NIV (rhEPO 0.16, CI 0.10 to 0.27; placebo 0.18, CI 0.11 to 0.30) did not differ between groups, also after stratification by onset and ALSFRS-R at baseline. Withdrawal due to AE was 16.5% in rhEPO and 8.3% in placebo. No differences were found for secondary outcomes. Conclusions RhEPO 40 000 IU fortnightly did not change the course of ALS. PMID:25595151

  9. Mixed-effects modelling of the interspecies pharmacokinetic scaling of pegylated human erythropoietin.

    PubMed

    Jolling, Koen; Perez Ruixo, Juan Jose; Hemeryck, Alex; Vermeulen, An; Greway, Tony

    2005-04-01

    -EPO in humans suggest a less frequent dosing regimen relative to erythropoietin and darbepoetin, potentially leading to a simplification of anemia management.

  10. Changes in erythroid membrane proteins during erythropoietin-mediated terminal differentiation.

    PubMed

    Koury, M J; Bondurant, M C; Rana, S S

    1987-12-01

    Membrane and membrane skeleton proteins were examined in erythroid progenitor cells during terminal differentiation. The employed model system of erythroid differentiation was that in which proerythroblasts from mice infected with the anemia-inducing strain of Friend virus differentiate in vitro in response to erythropoietin (EP). With this system, developmentally homogeneous populations of cells can be examined morphologically and biochemically as they progress from proerythroblasts through enucleated reticulocytes. alpha and beta spectrins, the major proteins of the erythrocyte membrane skeleton, are synthesized in the erythroblasts both before and after EP exposure. At all times large portions of the newly synthesized spectrins exist in and are turned over in the cytoplasm. The remaining newly synthesized spectrin is found in a cellular fraction containing total membranes. Pulse-chase experiments show that little of the cytoplasmic spectrins become membrane associated, but that the proportion of newly synthesized spectrin which is membrane associated increases as maturation proceeds. A membrane fraction enriched in plasma membranes has significant differences in the stoichiometry of spectrin accumulation as compared to total cellular membranes. Synthesis of band 3 protein, the anion transporter, is induced only after EP addition to the erythroblasts. All of the newly synthesized band 3 is membrane associated. A two-dimensional gel survey was conducted of newly synthesized proteins in the plasma membrane enriched fraction of the erythroblasts as differentiation proceeded. A majority of the newly synthesized proteins remain in the same proportion to each other during maturation; however, a few newly synthesized proteins greatly increase following EP induction while others decrease markedly. Of the radiolabeled proteins observed in two dimensional gels, only the spectrins, band 3 and actin become major proteins of the mature erythrocyte membrane. Examination of

  11. Transportation Security Administration

    MedlinePlus

    ... content Official website of the Department of Homeland Security Transportation Security Administration A - Z Index What Can I Bring? ... form Search the Site Main menu Administrator Travel Security Screening Special Procedures TSA Pre✓® Passenger Support Travel ...

  12. Administration on Aging

    MedlinePlus

    ... Federal Initiatives Career Opportunities Contact Us Administration on Aging (AoA) The Administration on Aging (AOA) is the ... themselves. Back to top Older Americans Act and Aging Network To meet the diverse needs of the ...

  13. Rehabilitation Services Administration

    MedlinePlus

    ... Contacts OSEP Reports & Resources RSA Welcome to RSA Rehabilitation Services Administration RSA Spotlight News Commissioner's Quarterly Newsletter ... The Office of Special Education and Rehabilitative Services’ Rehabilitation Services Administration is proud to announce the publication ...

  14. Administration on Aging

    MedlinePlus

    ... Administration on Aging Administration on Disabilities Center for Integrated Programs Center for Performance and Evaluation National Institute ... Project Aging Statistics Profile of Older Americans AGing Integrated Database (AGID) Census Data & Population Estimates Projected Future ...

  15. Legal and Administrative Language

    ERIC Educational Resources Information Center

    Schwarz, Hans

    1977-01-01

    A discussion of legal and administrative language, and the necessity for accurate translation of this language in the field of international relations. Topics treated are: characteristic features of legal and administrative terminology; the interpretation of it; and the technique of translating legal and administrative texts. (AMH)

  16. Women in Administration 1978.

    ERIC Educational Resources Information Center

    National Association of State Universities and Land Grant Colleges, Washington, DC. Office of Communications Services.

    In a survey by the National Association of State Universities and Land-Grant Colleges (NASULGC), women are shown to hold 2,905 of the 13,638 administrative positions reported by 106 major U.S. public universities--slightly more than 21 percent of the administrators at state and land-grant universities. The median number of women administrators at…

  17. School Business Administration.

    ERIC Educational Resources Information Center

    Jordan, K. Forbis; And Others

    This textbook reviews the principal concerns within each of 13 major responsibility areas in school business administration. The first chapter assesses the political, social, and economic context in which schools function and school administrators work. The role and function of the school business administrator within this context is addressed in…

  18. Comparison of two recombinant erythropoietin formulations in patients with anemia due to end-stage renal disease on hemodialysis: A parallel, randomized, double blind study

    PubMed Central

    Pérez-Oliva, Jorge F; Casanova-González, Martha; García-García, Idrian; Porrero-Martín, Pedro J; Valenzuela-Silva, Carmen M; Hernández-Montero, Tairí; Lagarde-Ampudia, Marcia; Casanova-Kutsareva, Yuri; Ávila-Albuerne, Yisel; Vargas-Batista, Alicia; Bobillo-López, Hailen; Herrera-Valdés, Raúl; López-Saura, Pedro A

    2005-01-01

    Background Recombinant human erythropoietin (EPO) is used for the treatment of last stage renal anemia. A new EPO preparation was obtained in Cuba in order to make this treatment fully nationally available. The aim of this study was to compare the pharmacokinetic, pharmacodynamic and safety properties of two recombinant EPO formulations in patients with anemia due to end-stage renal disease on hemodialysis. Methods A parallel, randomized, double blind study was performed. A single 100 IU/Kg EPO dose was administered subcutaneously. Heberitro (Heber Biotec, Havana, formulation A), a newly developed product and Eprex (CILAG AG, Switzerland, formulation B), as reference treatment were compared. Thirty-four patients with anemia due to end-stage renal disease on hemodialysis were included. Patients had not received EPO previously. Serum EPO level was measured by enzyme immunoassay (EIA) during 120 hours after administration. Clinical and laboratory variables were determined as pharmacodynamic and safety criteria until 216 hours. Results Both groups of patients were similar regarding all demographic and baseline characteristics. EPO kinetics profiles were similar for both formulations; the pharmacokinetic parameters were very close (i.e., AUC: 4667 vs. 4918 mIU.h/mL; Cmax: 119.1 vs. 119.7 mIU/mL; Tmax: 13.9 vs. 18.1 h; half-life, 20.0 vs. 22.5 h for formulations A and B, respectively). The 90% confidence intervals for the ratio between both products regarding these metrics were close to the 0.8 – 1.25 range, considered necessary for bioequivalence. Differences did not reach 20% in any case and were not determined by a formulation effect, but probably by a patients' variability effect. Concerning pharmacodynamic features, a high similitude in reticulocyte counts increments until 216 hours and the percentage decrease in serum iron until 120 hours was observed. There were no differences between formulations regarding the adverse events and their intensity. The more

  19. Diabetes mellitus abrogates erythropoietin-induced cardioprotection against ischemic-reperfusion injury by alteration of the RISK/GSK-3β signaling.

    PubMed

    Ghaboura, Nehmat; Tamareille, Sophie; Ducluzeau, Pierre-Henri; Grimaud, Linda; Loufrani, Laurent; Croué, Anne; Tourmen, Yves; Henrion, Daniel; Furber, Alain; Prunier, Fabrice

    2011-01-01

    Recent studies reported cardioprotective effects of erythropoietin (EPO) against ischemia-reperfusion (I/R) injury through activation of the reperfusion injury salvage kinase (RISK) pathway. As RISK has been reported to be impaired in diabetes and insulin resistance syndrome, we examined whether EPO-induced cardioprotection was maintained in rat models of type 1 diabetes and insulin resistance syndrome. Isolated hearts were obtained from three rat cohorts: healthy controls, streptozotocin (STZ)-induced diabetes, and high-fat diet (HFD)-induced insulin resistance syndrome. All hearts underwent 25 min ischemia and 30 min or 120 min reperfusion. They were assigned to receive either no intervention or a single dose of EPO at the onset of reperfusion. In hearts from healthy controls, EPO decreased infarct size (14.36 ± 0.60 and 36.22 ± 4.20% of left ventricle in EPO-treated and untreated hearts, respectively, p < 0.05) and increased phosphorylated forms of Akt, ERK1/2, and their downstream target GSK-3β. In hearts from STZ-induced diabetic rats, EPO did not decrease infarct size (32.05 ± 2.38 and 31.88 ± 1.87% in EPO-treated and untreated diabetic rat hearts, respectively, NS) nor did it increase phosphorylation of Akt, ERK1/2, and GSK-3β. In contrast, in hearts from HFD-induced insulin resistance rats, EPO decreased infarct size (18.66 ± 1.99 and 34.62 ± 3.41% in EPO-treated and untreated HFD rat hearts, respectively, p < 0.05) and increased phosphorylation of Akt, ERK1/2, and GSK-3β. Administration of GSK-3β inhibitor SB216763 was cardioprotective in healthy and diabetic hearts. STZ-induced diabetes abolished EPO-induced cardioprotection against I/R injury through a disruption of upstream signaling of GSK-3β. In conclusion, direct inhibition of GSK-3β may provide an alternative strategy to protect diabetic hearts against I/R injury.

  20. Both acute and prolonged administration of EPO reduce cerebral and systemic vascular conductance in humans.

    PubMed

    Rasmussen, Peter; Kim, Yu-Sok; Krogh-Madsen, Rikke; Lundby, Carsten; Olsen, Niels V; Secher, Niels H; van Lieshout, Johannes J

    2012-03-01

    Administration of erythropoietin (EPO) has been linked to cerebrovascular events. EPO reduces vascular conductance, possibly because of the increase in hematocrit. Whether EPO in itself affects the vasculature remains unknown; here it was evaluated in healthy males by determining systemic and cerebrovascular variables following acute (30,000 IU/d for 3 d; n=8) and chronic (5000 IU/week for 13 wk; n=8) administration of EPO, while the responsiveness of the vasculature was challenged during cycling exercise, with and without hypoxia. Prolonged administration of EPO increased hematocrit from 42.5 ± 3.7 to 47.6 ± 4.1% (P<0.01), whereas hematocrit was unaffected following acute EPO administration. Yet, the two EPO regimes increased arterial pressure similarly (by 8±4 and 7±3 mmHg, respectively; P=0.01) through reduced vascular conductance (by 7±3 and 5±2%; P<0.05). Also, both EPO regimes widened the arterial-to-jugular O(2) differences at rest as well as during normoxic and hypoxic exercise (P<0.01), which indicated reduced cerebral blood flow despite preserved dynamic cerebral autoregulation, and an increase in middle cerebral artery mean blood flow velocity (P<0.05), therefore, reflected vasoconstriction. Thus, administration of EPO to healthy humans lowers systemic and cerebral conductance independent of its effect on hematocrit.

  1. The use of erythropoietin-stimulating agents versus supportive care in newborns with hereditary spherocytosis: a single centre's experience.

    PubMed

    Morrison, Jacqueline F; Neufeld, Ellis J; Grace, Rachael F

    2014-08-01

    Hereditary Spherocytosis (HS) is a common haemolytic anaemia in which 75% of cases are autosomal dominant. As most newborns with HS have a family history of disease, haematologists often see these infants before their physiologic haemoglobin nadir, which is exaggerated in comparison with healthy infants. The objective of this study was to evaluate the frequency of implementation and cost of erythropoietin-stimulating agents (EPO) versus transfusion in infants with HS at a single paediatric programme. In the last decade, only 15% of infants with HS at our centre have been treated with EPO, which costs twice that of a single transfusion and EPO treated infants did not always avoid transfusion. Infrequent prescription of EPO therapy to infants with HS at our centre may be related to the incomplete data supporting its use.

  2. Soluble erythropoietin receptor is present in the mouse brain and is required for the ventilatory acclimatization to hypoxia.

    PubMed

    Soliz, Jorge; Gassmann, Max; Joseph, Vincent

    2007-08-15

    While erythropoietin (Epo) and its receptor (EpoR) have been widely investigated in brain, the expression and function of the soluble Epo receptor (sEpoR) remain unknown. Here we demonstrate that sEpoR, a negative regulator of Epo's binding to the EpoR, is present in the mouse brain and is down-regulated by 62% after exposure to normobaric chronic hypoxia (10% O2 for 3 days). Furthermore, while normoxic minute ventilation increased by 58% in control mice following hypoxic acclimatization, sEpoR infusion in brain during the hypoxic challenge efficiently reduced brain Epo concentration and abolished the ventilatory acclimatization to hypoxia (VAH). These observations imply that hypoxic downregulation of sEpoR is required for adequate ventilatory acclimatization to hypoxia, thereby underlying the function of Epo as a key factor regulating oxygen delivery not only by its classical activity on red blood cell production, but also by regulating ventilation.

  3. The influence of Erythropoietin on platelet activation, thrombin generation and FVII/active FVII in patients with AMI

    PubMed Central

    2014-01-01

    Background Erythropoietin (Epo) has been shown to improve myocardial function in models of experimental myocardial infarction, but has also been associated with a rise in thromboembolic events. Thus, the aim of this study was to investigate the influence of Epo on platelet activation and coagulation in patients with acute myocardial infarction (AMI). Methods The study was designed as a substudy of the randomised, double-blind, placebo controlled REVIVAL-3 (REgeneration of VItal Myocardium in ST-Segment EleVation MyocardiAL Infarction by Erythropoietin) study that investigated the effects of recombinant human Epo in AMI. Serial venous blood samples were collected before and after study medication. Circulating prothrombin fragment F1 + 2, FVII, active FVII, beta thromboglobulin (TG) and P-Selectin were measured before and 60 hours after randomization by immunoassay (n = 94). In a randomly selected subgroup platelet aggregation was measured using whole blood aggregometry (Multiplate Analyzer, n = 45). Results After 5 days an increase in FVII was observed after Epo as compared to placebo (P = 0.02), yet active FVII and prothrombin fragment F1 + 2 remained unchanged. Moreover, no statistically significant differences in circulating TG or P-selectin were observed between the groups. As an expected response to peri-interventional therapy with clopidogrel and aspirin, platelet aggregation after stimulation with ADP, TRAP, ASPI or collagen decreased 12 hours and 2 days after PCI. However, no difference between the Epo and the placebo group was observed. Conclusion After treatment with Epo in patients with AMI a slight increase in circulating FVII after Epo was not associated with an increase in active FVII, prothrombin fragment F1 + 2, TG or P-selectin. Moreover, platelet aggregation was not altered after treatment with Epo as compared to placebo. Trial registration ClinicalTrials.gov Identifier: NCT01761435 PMID:25228850

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

    PubMed Central

    Hoedt, Andrea; Christensen, Britt; Nellemann, Birgitte; Mikkelsen, Ulla Ramer; Hansen, Mette; Schjerling, Peter

    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 show, in human skeletal muscle, that treatment with an Epo‐stimulating agent (darbepoetin‐α) in vivo increases the content of MyoD+ SCs in healthy young men. Moreover, we report that Epo receptor mRNA is expressed in adult human SCs, suggesting that Epo may directly target SCs through ligand‐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. Abstract 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 to investigate the effects of prolonged erythropoiesis‐stimulating agent (ESA; darbepoetin‐α) treatment and endurance training, separately and combined, on SC quantity and commitment in human skeletal muscle. Thirty‐five healthy, untrained men were randomized into four groups: sedentary‐placebo (SP, n = 9), sedentary‐ESA (SE, n = 9), training‐placebo (TP, n = 9) or training‐ESA (TE, n = 8). ESA/placebo was injected once weekly and training consisted of ergometer cycling three times a week for 10 weeks. Prior to and following the intervention period, blood samples and muscle biopsies were obtained and maximal oxygen uptake (V˙O2, max ) was measured. Immunohistochemical analyses were used to quantify fibre type specific SCs (Pax7+), myonuclei

  5. Veterans Administration Databases

    Cancer.gov

    The Veterans Administration Information Resource Center provides database and informatics experts, customer service, expert advice, information products, and web technology to VA researchers and others.

  6. Post-treatment effects of erythropoietin and nordihydroguaiaretic acid on recovery from cisplatin-induced acute renal failure in the rat.

    PubMed

    Lee, Dong Won; Kwak, Ihm Soo; Lee, Soo Bong; Song, Sang Heon; Seong, Eun Young; Yang, Byeong Yun; Lee, Min Young; Sol, Mee Young

    2009-01-01

    5-lipoxygenase inhibitor and human recombinant erythropoietin might accelerate renal recovery in cisplatin-induced acute renal failure rats. Male Sprague-Dawley rats were randomized into four groups: 1) normal controls; 2) Cisplatin group-cisplatin induced acute renal failure (ARF) plus vehicle treatment; 3) Cisplatin+nordihydroguaiaretic acid (NDGA) group-cisplatin induced ARF plus 5-lipoxygenase inhibitor treatment; 4) Cisplatin+erythropoietin (EPO) group-cisplatin induced ARF plus erythropoietin treatment. On day 10 (after 7 daily injections of NDGA or EPO), urea nitrogen and serum Cr concentrations were significantly lower in the Cisplatin+NDGA and Cisplatin+EPO groups than in the Cisplatin group, and 24 hr urine Cr clearances were significantly higher in the Cisplatin+EPO group than in the Cisplatin group. Semi-quantitative assessments of histological lesions did not produce any significant differences between the three treatment groups. Numbers of PCNA(+) cells were significantly higher in Cisplatin, Cisplatin+NDGA, and Cisplatin+EPO groups than in normal controls. Those PCNA(+) cells were significantly increased in Cisplatin+NDGA group. These results suggest that EPO and also NDGA accelerate renal function recovery by stimulating tubular epithelial cell regeneration.

  7. Migrant Education Administrative Guide.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh. Div. of Compensatory Education.

    Relating specifically to the North Carolina migrant education program's administrative responsibilities, this guide is designed to aid administrators in program management, monitoring project activities, project evaluation, self-assessment, determining needs for training and staff development, site-visit preparation, policy development, and…

  8. Champions of Children. Administrators . . .

    ERIC Educational Resources Information Center

    Chaffee, John; Olds, H. Robert

    Today, in an era of taxpayer revolts, lack of clarity in values, and changing family structure, children need advocates in the political arena as well as in the schools. This pamphlet suggests that administrators are in an excellent position to defend the rights of children on all fronts. It focuses on what administrators have done and specific…

  9. The Administrative Power Grab

    ERIC Educational Resources Information Center

    Sorenson, Richard D.

    2007-01-01

    Administrative power for some school teachers can be an aphrodisiac that can be applied negatively, especially when a leader has devastating instinct for the weaknesses of others. A leader's intellect and heart closes shop and ceases to function when drunk on power. In this article, the author describes how the use of administrative power can be…

  10. Traditionalism and Educational Administration.

    ERIC Educational Resources Information Center

    Holmes, Mark

    Administration is defined as the enactment of moral choices influencing subordinates within an organizational setting. It is distinguished from management, which is considered to involve a lower level of discretion. Educational administration is therefore in the moral domain; it involves discretionary, moral choices in a field that is itself moral…

  11. Test Administration Models

    ERIC Educational Resources Information Center

    Becker, Kirk A.; Bergstrom, Betty A.

    2013-01-01

    The need for increased exam security, improved test formats, more flexible scheduling, better measurement, and more efficient administrative processes has caused testing agencies to consider converting the administration of their exams from paper-and-pencil to computer-based testing (CBT). Many decisions must be made in order to provide an optimal…

  12. The Administrative Team.

    ERIC Educational Resources Information Center

    Ohio Association of Elementary School Principals, Westerville.

    Although needs of school districts vary with size, degree of teacher negotiation procedures, and type of community involvement, the administrative team model is presented as an effective, appropriate administrative organization. Based on an assumption that each level of authority in a school district possesses and exercises expertise and unique…

  13. Administrative Theory in Transition.

    ERIC Educational Resources Information Center

    Griffiths, Daniel E.

    This monograph analyzes transition in educational administrative theory. A brief introductory section describes the theoretical movement, the substance and repercussions of Thomas Greenfield's critique of educational administrative theory in 1974, and emerging qualitative approaches. Seven readings, all written by the volume's author, view…

  14. Improving Educational Administrative Decisions.

    ERIC Educational Resources Information Center

    Wolfe, A. E.

    This paper discusses the financial crisis facing public education in the United States today and argues that the most effective response to this crisis is to improve the decision-making skills of educational administrators. Based on a review of the literature on administrative decision-making and organizational change, the author examines several…

  15. Rural Administrative Leadership Handbook.

    ERIC Educational Resources Information Center

    Tift, Carolyn

    This resource book on rural administrative leadership is the result of 1988 interviews with school administrators involved in successful rural educational programs. The material is divided into eight chapters, each self-contained for separate use. Chapter 1, "Getting to Know the Community," addresses qualities of living and working in…

  16. Pharmacokinetics and selected pharmacodynamics of cobalt following a single intravenous administration to horses.

    PubMed

    Knych, H K; Arthur, R M; Mitchell, M M; Holser, I; Poppenga, R; Smith, L L; Helm, M N; Sams, R A; Gaskill, C L

    2015-07-01

    Cobalt has been used by human athletes due to its purported performance-enhancing effects. It has been suggested that cobalt administration results in enhanced erythropoiesis, secondary to increased circulating erythropoietin (EPO) concentrations leading to improvements in athletic performance. Anecdotal reports of illicit administration of cobalt to horses for its suspected performance enhancing effects have led us to investigate the pharmacokinetics and pharmacodynamic effects of this compound when administered in horses, so as to better regulate its use. In the current study, 18 horses were administered a single intravenous dose of cobalt chloride or cobalt gluconate and serum and urine samples collected for up to 10 days post administration. Cobalt concentrations were measured using inductively coupled plasma mass spectrometry (ICP-MS) and pharmacokinetic parameters determined. Additional blood samples were collected for measurement of equine EPO concentrations as well as to assess any effects on red blood cell parameters. Horses were observed for adverse effects and heart rate monitored for the first 4 h post administration. Cobalt was characterized by a large volume of distribution (0.939 L/kg) and a prolonged gamma half-life (156.4 h). Cobalt serum concentrations were still above baseline values at 10 days post administration. A single administration of cobalt had no effect on EPO concentrations, red blood cell parameters or heart rate in any of the horses studied and no adverse effects were noted. Based on the prolonged gamma half-life and prolonged residence time, regulators should be able to detect administration of a single dose of cobalt to horses.

  17. Drug Education for Administrators

    ERIC Educational Resources Information Center

    Hackett, Peter; McKeon, Thomas L.

    1976-01-01

    The formulation of a drug policy and the implementation of that policy in a firm but fair manner are the responsibility of the school administrator. Authors give serious consideration to this responsibility. (Editor/RK)

  18. Food and Drug Administration

    MedlinePlus

    ... blog post. April 11, 2017 ‘Organs-on-Chips’ Technology: FDA Testing Groundbreaking Science More FDA Voice Blog ... FEAR Act Site Map Nondiscrimination Website Policies U.S. Food and Drug Administration 10903 New Hampshire Avenue Silver ...

  19. Administrative Law Judges

    EPA Pesticide Factsheets

    The Administrative Law Judges conduct hearings and render decisions in proceedings between the EPA and persons, businesses, government entities, and other organizations which are or are alleged to be regulated under environmental laws.

  20. Needed: Nursing Administration Leaders

    ERIC Educational Resources Information Center

    Blair, Eunice M.

    1976-01-01

    A master's program that synthesizes clinical nursing knowledge with management theory and skills is one way to prepare nursing service administrators capable of exerting an influence on today's complex health care system. (Editor)

  1. The Administrator Selection Process

    ERIC Educational Resources Information Center

    Griffin, Michael F.

    1974-01-01

    Proposes that education establish for administrators systematic, rigorous, albeit subjective, selection procedures that recognize the principle of organizational democracy and the public nature of the educational enterprise. (Author/DN)

  2. Confrontation and Administrative Response

    ERIC Educational Resources Information Center

    Auerbach, Arnold J.

    1969-01-01

    Describes some of the sociological and psychological effects of organizational conflict and offers 10 operational principles to guide public administrators of schools and social agencies in meeting the confrontation tactics of activist groups. (JH)

  3. One for the Administrators

    ERIC Educational Resources Information Center

    American School and University, 1978

    1978-01-01

    Earth berms, a heavily insulated roof, and a narrow band of thermal pane windows, save energy at the administrative headquarters of the Anoka Hennepin school district in Coon Rapids, a suburb of Minneapolis, Minnesota. (Author/MLF)

  4. Goldstone (GDSCC) administrative computing

    NASA Technical Reports Server (NTRS)

    Martin, H.

    1981-01-01

    The GDSCC Data Processing Unit provides various administrative computing services for Goldstone. Those activities, including finance, manpower and station utilization, deep-space station scheduling and engineering change order (ECO) control are discussed.

  5. Identification of Cell Type-Specific Differences in Erythropoietin Receptor Signaling in Primary Erythroid and Lung Cancer Cells

    PubMed Central

    Salopiata, Florian; Depner, Sofia; Wäsch, Marvin; Böhm, Martin E.; Mücke, Oliver; Plass, Christoph; Lehmann, Wolf D.; Kreutz, Clemens; Timmer, Jens; Klingmüller, Ursula

    2016-01-01

    Lung cancer, with its most prevalent form non-small-cell lung carcinoma (NSCLC), is one of the leading causes of cancer-related deaths worldwide, and is commonly treated with chemotherapeutic drugs such as cisplatin. Lung cancer patients frequently suffer from chemotherapy-induced anemia, which can be treated with erythropoietin (EPO). However, studies have indicated that EPO not only promotes erythropoiesis in hematopoietic cells, but may also enhance survival of NSCLC cells. Here, we verified that the NSCLC cell line H838 expresses functional erythropoietin receptors (EPOR) and that treatment with EPO reduces cisplatin-induced apoptosis. To pinpoint differences in EPO-induced survival signaling in erythroid progenitor cells (CFU-E, colony forming unit-erythroid) and H838 cells, we combined mathematical modeling with a method for feature selection, the L1 regularization. Utilizing an example model and simulated data, we demonstrated that this approach enables the accurate identification and quantification of cell type-specific parameters. We applied our strategy to quantitative time-resolved data of EPO-induced JAK/STAT signaling generated by quantitative immunoblotting, mass spectrometry and quantitative real-time PCR (qRT-PCR) in CFU-E and H838 cells as well as H838 cells overexpressing human EPOR (H838-HA-hEPOR). The established parsimonious mathematical model was able to simultaneously describe the data sets of CFU-E, H838 and H838-HA-hEPOR cells. Seven cell type-specific parameters were identified that included for example parameters for nuclear translocation of STAT5 and target gene induction. Cell type-specific differences in target gene induction were experimentally validated by qRT-PCR experiments. The systematic identification of pathway differences and sensitivities of EPOR signaling in CFU-E and H838 cells revealed potential targets for intervention to selectively inhibit EPO-induced signaling in the tumor cells but leave the responses in erythroid

  6. Three Tyrosine Residues in the Erythropoietin Receptor Are Essential for Janus Kinase 2 V617F Mutant-induced Tumorigenesis.

    PubMed

    Ueda, Fumihito; Tago, Kenji; Tamura, Hiroomi; Funakoshi-Tago, Megumi

    2017-02-03

    The erythropoietin receptor (EpoR) regulates development of blood cells, and its full activation normally requires the cytokine erythropoietin (Epo). In the case of myeloproliferative neoplasms (MPN), Epo-independent signaling through EpoR can be caused by a point mutation, V617F, in the EpoR-interacting tyrosine kinase Janus kinase 2 (JAK2). In cells expressing the JAK2 V617F mutant, eight tyrosine residues in the intracellular domain of EpoR are phosphorylated, but the functional role of these phosphorylations in oncogenic signaling is incompletely understood. Here, to evaluate the functional consequences of the phosphorylation of these tyrosine residues, we constructed an EpoR-8YF mutant in which we substituted all eight tyrosine residues with phenylalanine. Co-expression of EpoR-8YF with the JAK2 V617F mutant failed to induce cytokine-independent cell proliferation and tumorigenesis, indicating that JAK2-mediated EpoR phosphorylation is the reason for JAK2 V617F mutant-induced oncogenic signaling. An exhaustive mutational analysis of the eight EpoR tyrosine residues indicated that three of these residues, Tyr-343, Tyr-460, and Tyr-464, are required for the JAK2 V617F mutant to exhibit its oncogenic activity. We also showed that phosphorylation at these three residues was necessary for full activation of the transcription factor STAT5, which is a critical downstream factor of JAK2 V617F-induced oncogenic signaling. In contrast, Epo stimulation could moderately stimulate the proliferation of cells expressing wild type JAK2 and EpoR-8YF, suggesting that the requirement of the phosphorylation of these three tyrosine residues seems to be specific for the oncogenic proliferation provoked by V617F mutation. Collectively, these results have revealed that phosphorylation of Tyr-343, Tyr-460, and Tyr-464 in EpoR underlies JAK2 V617F mutant-induced tumorigenesis. We propose that the targeted disruption of this pathway has therapeutic utility for managing MPN.

  7. Company Administration Study.

    DTIC Science & Technology

    1974-01-01

    iTRATION CENTER AND FORT BENJAMIN HARRISON FORT BENJAMIN HARRISON. INDIANA 46216 ATZI -XO 16 October 1973 SUBJECT: Letter of Instruction - Company...Mail, files, records management* publications, voting, etc.). ... AnnexA II ATZI -XO 18 October 1973 SUBJECT: Letter of Instruction - Company...administration as follows: A. 2 I * * " " " ’+ " " ’ ’ ’ ’’ ’ , ’" I ATZI -XO 18 October 1973 SUBJECT: Letter of Instruction - Company Administration Study tea

  8. Hematopoietic cell kinase (HCK) is a potential therapeutic target for dysplastic and leukemic cells due to integration of erythropoietin/PI3K pathway and regulation of erythropoiesis: HCK in erythropoietin/PI3K pathway.

    PubMed

    Roversi, Fernanda Marconi; Pericole, Fernando Vieira; Machado-Neto, João Agostinho; da Silva Santos Duarte, Adriana; Longhini, Ana Leda; Corrocher, Flávia Adolfo; Palodetto, Bruna; Ferro, Karla Priscila; Rosa, Renata Giardini; Baratti, Mariana Ozello; Verjovski-Almeida, Sergio; Traina, Fabiola; Molinari, Alessio; Botta, Maurizio; Saad, Sara Teresinha Olalla

    2017-02-01

    New drug development for neoplasm treatment is nowadays based on molecular targets that participate in the disease pathogenesis and tumor phenotype. Herein, we describe a new specific pharmacological hematopoietic cell kinase (HCK) inhibitor (iHCK-37) that was able to reduce PI3K/AKT and MAPK/ERK pathways activation after erythropoietin induction in cells with high HCK expression: iHCK-37 treatment increased leukemic cells death and, very importantly, did not affect normal hematopoietic stem cells. We also present evidence that HCK, one of Src kinase family (SFK) member, regulates early-stage erythroid cell differentiation by acting as an upstream target of a frequently deregulated pathway in hematologic neoplasms, PI3K/AKT and MAPK/ERK. Notably, HCK levels were highly increased in stem cells from patients with some diseases, as Myelodysplastic Syndromes (MDS) and Acute Myeloid Leukemia (AML), that are associated with ineffective erythropoiesis These discoveries support the exploration of the new pharmacological iHCK-37 in future preclinical and clinical studies.

  9. Intranasal formulation of erythropoietin (EPO) showed potent protective activity against amyloid toxicity in the Aβ₂₅₋₃₅ non-transgenic mouse model of Alzheimer's disease.

    PubMed

    Maurice, Tangui; Mustafa, Muhammad-Hariri; Desrumaux, Catherine; Keller, Emeline; Naert, Gaëlle; de la C García-Barceló, María; Rodríguez Cruz, Yamila; Garcia Rodríguez, Julío César

    2013-11-01

    Erythropoietin (EPO) promotes neurogenesis and neuroprotection. We here compared the protection induced by two EPO formulations in a rodent model of Alzheimer's disease (AD): rHu-EPO and a low sialic form, Neuro-EPO. We used the intracerebroventricular administration of aggregated Aβ₂₅₋₃₅ peptide, a non-transgenic AD model. rHu-EPO was tested at 125-500 µg/kg intraperitoneally and Neuro-EPO at 62-250 µg/kg intranasally (IN). Behavioural procedures included spontaneous alternation, passive avoidance, water-maze and object recognition, to address spatial and non-spatial, short- and long-term memories. Biochemical markers of Aβ₂₅₋₃₅ toxicity in the mouse hippocampus were examined and cell loss in the CA1 layer was determined. rHu-EPO and Neuro-EPO led to a significant prevention of Aβ₂₅₋₃₅-induced learning deficits. Both EPO formulations prevented the induction of lipid peroxidation in the hippocampus, showing an antioxidant activity. rHu-EPO (250 µg/kg) or Neuro-EPO (125 µg/kg) prevented the Aβ₂₅₋₃₅-induced increase in Bax level, TNFα and IL-1β production and decrease in Akt activation. A significant prevention of the Aβ₂₅₋₃₅-induced cell loss in CA1 was also observed. EPO is neuroprotective in the Aβ₂₅₋₃₅ AD model, confirming its potential as an endogenous neuroprotection system that could be boosted for therapeutic efficacy. We here identified a new IN formulation of EPO showing high neuroprotective activity. Considering its efficacy, ease and safety, IN Neuro-EPO is a new promising therapeutic agent in AD.

  10. Characterization of the pharmacokinetics of human recombinant erythropoietin in blood and brain when administered immediately after lateral fluid percussion brain injury and its pharmacodynamic effects on IL-1beta and MIP-2 in rats.

    PubMed

    Lieutaud, Thomas; Andrews, Peter J D; Rhodes, Jonathan K J; Williamson, Robert

    2008-10-01

    This study sought to determine the bio-availability of recombinant human erythropoietin (EPO) in the brain and blood and its effects on the cerebral concentrations of the inflammatory mediators interleukin-1beta (IL-1beta) and macrophage-inflammation protein-2 (MIP-2) following lateral fluid percussion brain injury (FPI) in the rat. After induction of moderate FPI (1.6-1.8 atm), EPO was injected intraperitoneally (IP) or intravenously (IV) at doses of 1000-5000 U/kg in a randomized and blinded manner. Animals were then sacrificed at time points (4, 8, 12, 24 h) post-trauma, and the brain concentrations of EPO, IL-1beta, and MIP-2 were determined. EPO administration leads to a dose-dependent increase in the brain concentration of the drug; however, this could only be detected at doses of 3000 and 5000 U/kg. The cerebral concentration peaked in the first 4 h following trauma. EPO concentrations were significantly higher and decreased more slowly in the traumatized cortex compared to the contralateral side (p<0.0125). IV EPO (5000 U/kg) produced slightly higher concentrations of EPO than same doses injected IP; however, this was not significant. At a dose of 5000 U/kg, EPO significantly reduced the increase in IL-1beta at 8 and 12 h in both cortical sides. It also reduced the increase in MIP-2 but only after 8 h, on the contralateral side and after 12 h on the ipsilateral side. Our results suggest that EPO crosses the blood-brain barrier (BBB) by 4 h after trauma and is localized primarily in the traumatized cortex. Further, it has biological efficacy at 8 h on several inflammatory proteins, yet must be employed at high doses to cross the BBB.

  11. Erythropoietin-mediated expression of placenta growth factor is regulated via activation of hypoxia-inducible factor-1α and post-transcriptionally by miR-214 in sickle cell disease.

    PubMed

    Gonsalves, Caryn S; Li, Chen; Mpollo, Marthe-Sandrine Eiymo Mwa; Pullarkat, Vinod; Malik, Punam; Tahara, Stanley M; Kalra, Vijay K

    2015-06-15

    Placental growth factor (PlGF) plays an important role in various pathological conditions and diseases such as inflammation, cancer, atherosclerosis and sickle cell disease (SCD). Abnormally high PlGF levels in SCD patients are associated with increased inflammation and pulmonary hypertension (PHT) and reactive airway disease; however, the transcriptional and post-transcriptional mechanisms regulating PlGF expression are not well defined. Herein, we show that treatment of human erythroid cells and colony forming units with erythropoietin (EPO) increased PlGF expression. Our studies showed EPO-mediated activation of HIF-1α led to subsequent binding of HIF-1α to hypoxia response elements (HREs) within the PlGF promoter, as demonstrated by luciferase transcription reporter assays and ChIP analysis of the endogenous gene. Additionally, we showed miR-214 post-transcriptionally regulated the expression of PlGF as demonstrated by luciferase reporter assays using wild-type (wt) and mutant PlGF-3'-UTR constructs. Furthermore, synthesis of miR-214, located in an intron of DNM3 (dynamin 3), was transcriptionally regulated by transcription factors, peroxisome proliferator-activated receptor-α (PPARα) and hypoxia-inducible factor-1α (HIF-1α). These results were corroborated in vivo wherein plasma from SCD patients and lung tissues from sickle mice showed an inverse correlation between PlGF and miR-214 levels. Finally, we observed that miR-214 expression could be induced by fenofibrate, a Food and Drug Administration (FDA) approved PPARα agonist, thus revealing a potential therapeutic approach for reduction in PlGF levels by increasing miR-214 transcription. This strategy has potential clinical implications for several pathological conditions including SCD.

  12. Erythropoietin attenuates intracerebral hemorrhage by diminishing matrix metalloproteinases and maintaining blood-brain barrier integrity in mice.

    PubMed

    Li, Y; Ogle, M E; Wallace, G C; Lu, Z Y; Yu, S P; Wei, L

    2008-01-01

    The protective mechanism of recombinant human erythropoietin (rhEPO) on blood-brain barrier (BBB) after brain injury is associated with the attenuation of neuro-inflammation. We hypothesize that rhEPO treatment after intracerebral hemorrhage (ICH) modulates matrix metalloproteinase (MMP) activity, maintains BBB integrity, and reduces BBB breakdown-associated inflammation. Adult male 129S2/sv mice were subjected to autologous whole blood-induced ICH. rhEPO or saline was administered intraperitoneally immediately after surgery and for 3 more days until day of sacrifice. BBB permeability was measured by Evans blue leakage, and edema was assessed by brain water content. Immunofluorescence and Western blotting were performed to detect expression of tight junction marker occludin, type IV collagen, MMPs, tissue inhibitor of metalloproteinase (TIMP), and glial fibrillary acidic protein, rhEPO prevented Evans blue leakage, reduced brain edema, and preserved expression of occludin and collagen IV. rhEPO treatment decreased MMP-2 expression, increased TIMP-2 expression, and reduced the number of reactive astrocytes in the brain compared to saline control. We conclude that rhEPO reduces MMP activity, BBB disruption, and the glial cell inflammatory reaction 3 days after ICH. Our study provides additional evidence for the mechanism of rhEPO's neurovascular protective effects and a potential clinical application in the treatment of ICH.

  13. Erythropoietin promotes regeneration of adult CNS neurons via Jak2/Stat3 and PI3K/AKT pathway activation.

    PubMed

    Kretz, Alexandra; Happold, Caroline J; Marticke, Julia K; Isenmann, Stefan

    2005-08-01

    The cytokine hormone erythropoietin (EPO) has proved neuroprotective in CNS injury, and clinical trials for ischemic stroke are ongoing. The capability of EPO to restore postmitotic CNS architecture and function by fibre regeneration has not been examined. Here, we compared in vitro outgrowth capacity of adult retinal ganglion cells (RGCs) following optic nerve (ON) lesion in the presence and absence of EPO. Immediate EPO conditioning in vivo, or delayed EPO treatment of cultures with 10--10,000 IU rhEPO significantly increased numbers (2.66-fold) and length (8.31-fold) of newly generated neurites, without evoking rheological complications. EPO induced Stat3 phosphorylation in RGCs, and inhibition of Jak2/Stat3 abolished EPO-induced growth. EPO-facilitated neuritogenesis was paralleled by upregulation of Bcl-X(L), a Bcl-2 homologue capable of promoting RGC regeneration. The PI3K/Akt pathway was also involved in antiapoptotic and regeneration-enhancing EPO actions. In conclusion, EPO treatment may offer a unique dual-function strategy for neuroprotection and regeneration.

  14. Erythropoietin as neuroprotective and neuroregenerative treatment strategy: comprehensive overview of 12 years of preclinical and clinical research.

    PubMed

    Sargin, Derya; Friedrichs, Heidi; El-Kordi, Ahmed; Ehrenreich, Hannelore

    2010-12-01

    Erythropoietin (EPO), originally discovered as hematopoietic growth factor, has direct effects on cells of the nervous system that make it a highly attractive candidate drug for neuroprotection/neuroregeneration. Hardly any other compound has led to so much preclinical work in the field of translational neuroscience than EPO. Almost all of the >180 preclinical studies performed by many independent research groups from all over the world in the last 12 years have yielded positive results on EPO as a neuroprotective drug. The fact that EPO was approved for the treatment of anemia >20 years ago and found to be well tolerated and safe, facilitated the first steps of translation from preclinical findings to the clinic. On the other hand, the same fact, naturally associated with loss of patent protection, hindered to develop EPO as a highly promising therapeutic strategy for application in human brain disease. Therefore, only few clinical neuroprotection studies have been concluded, all with essentially positive and stimulating results, but no further development towards the clinic has occurred thus far. This article reviews the preclinical and clinical work on EPO for the indications neuroprotection/neuroregeneration and cognition, and hopefully will stimulate new endeavours promoting development of EPO for the treatment of human brain diseases.

  15. Increased bone formation in a rabbit long-bone defect model after single local and single systemic application of erythropoietin.

    PubMed

    Omlor, Georg W; Kleinschmidt, Kerstin; Gantz, Simone; Speicher, Anja; Guehring, Thorsten; Richter, Wiltrud

    2016-08-01

    Background and purpose - Delayed bone healing with non-union is a common problem. Further options to increase bone healing together with surgery are needed. We therefore evaluated a 1-dose single application of erythropoietin (EPO), applied either locally to the defect or systemically during surgery, in a critical-size rabbit long-bone defect. Material and methods - 19 New Zealand White rabbits received a 15-mm defect in the radius diaphysis. An absorbable gelatin sponge was soaked with saline (control group and systemic treatment group) or EPO (local treatment group) and implanted into the gap. The systemic treatment group received EPO subcutaneously. In vivo micro-CT analysis was performed 4, 8, and 12 weeks postoperatively. Vascularization was evaluated histologically. Results - Semiquantitative histomorphometric and radiological evaluation showed increased bone formation (2.3- to 2.5-fold) in both treatment groups after 12 weeks compared to the controls. Quantitative determination of bone volume and tissue volume showed superior bone healing after EPO treatment at all follow-up time points, with the highest values after 12 weeks in locally treated animals (3.0- to 3.4-fold). More vascularization was found in both EPO treatment groups. Interpretation - Initial single dosing with EPO was sufficient to increase bone healing substantially after 12 weeks of follow-up. Local application inside the defect was most effective, and it can be administered directly during surgery. Apart from effects on ossification, systemic and local EPO treatment leads to increased callus vascularization.

  16. Erythropoietin improves memory function with reducing endothelial dysfunction and amyloid-beta burden in Alzheimer's disease models.

    PubMed

    Lee, Soon-Tae; Chu, Kon; Park, Jung-Eun; Jung, Keun-Hwa; Jeon, Daejong; Lim, Ji-Youn; Lee, Sang Kun; Kim, Manho; Roh, Jae-Kyu

    2012-01-01

    Neurovascular degeneration contributes to the pathogenesis of Alzheimer's disease (AD). Because erythropoietin (EPO) promotes endothelial regeneration, we investigated the therapeutic effects of EPO in animal models of AD. In aged Tg2576 mice, EPO receptors (EPORs) were expressed in the cortex and hippocampus. Tg2576 mice were treated with daily injection of EPO (5000 IU/kg/day) for 5 days. At 14 days, EPO improved contextual memory as measured by fear-conditioning test. EPO enhanced endothelial proliferation and the level of synaptophysin expression in the brain. EPO also increased capillary density, and decreased the level of the receptor for advanced glycation endproducts (RAGE) in the brain, while decreasing in the amount of amyloid plaque and amyloid-β (Aβ). In cultured human endothelial cells, EPO enhanced angiogenesis and suppressed the expression of the RAGE. These results show that EPO improves memory and ameliorates endothelial degeneration induced by Aβ in AD models. This pre-clinical evidence suggests that EPO may be useful for the treatment of AD.

  17. Inhibiting PPARγ by erythropoietin while upregulating TAZ by IGF1 synergistically promote osteogenic differentiation of mesenchymal stem cells.

    PubMed

    Zhou, Jianwei; Wei, Fangyuan; Ma, Yuquan

    2016-09-09

    Erythropoietin (EPO) is reported to promote osteogenesis and inhibit adipogenesis of mesenchymal stem cells (MSC) through inhibiting PPARγ, while insulin-like growth factor 1 (IGF1) is able to enhance osteogenesis via upregulating transcriptional coactivator with PDZ-binding motif (TAZ). The different targets of EPO and IGF1 suggested their potential synergism to enhance osteogenesis. In this study, we aimed to determine the potential synergism of EPO and IGF1 and its efficacy on MSC differentiation. Rat adipose-derived mesenchymal stem cells (ADSCs) were separately treated with EPO, IGF1 and EPO/IGF1. It was observed that the co-treatment using EPO and IGF1 was able to potently promote the osteogenic differentiation of rat ADSCs compared with EPO or IGF1 alone, which offered a promising effective option to strengthen bone tissue regeneration for bone defects. Further, we demonstrated that the enhanced osteogenic differentiation by EPO and IGF1 co-treatment was almost counteracted by activating PPARγ through PPARγ agonist, RSG, and blocking TAZ through TAZ silencing RNA, siTAZ. Thus, it could be concluded that EPO and IGF1 possessed a potent synergism in promoting osteogenic differentiation, and the synergism was mainly attributed to co-regulation of different osteogenic regulators PPARγ and TAZ, which were targeted genes of EPO and IGF1 respectively.

  18. Retinoic acid, hypoxia, and GATA factors cooperatively control the onset of fetal liver erythropoietin expression and erythropoietic differentiation.

    PubMed

    Makita, Takako; Duncan, Stephan A; Sucov, Henry M

    2005-04-01

    The cytokine erythropoietin (Epo) is an essential factor promoting the survival, proliferation, and differentiation of erythroid progenitor cells. Epo expression and the initial phase of definitive erythropoietic differentiation in the fetal liver (E9-E12) are compromised in mouse embryos lacking the retinoic acid receptor RXRalpha. Our previous work demonstrated that the Epo gene is a direct target of retinoic acid action, via a retinoic acid receptor binding site in the Epo gene enhancer. However, Epo expression and erythropoietic differentiation become normalized in RXRalpha mutants from E12. In this study, we have investigated the molecular mechanisms underlying the transition in Epo gene regulation from RXRalpha-dependence to RXRalpha-independence. We find that three independent regulatory components are required for high level Epo expression in the early fetal liver: ligand-activated retinoic acid receptors, the hypoxia-regulated factor HIF1, and GATA factors. By E11.5, the fetal liver is no longer hypoxic, and retinoic acid signaling is no longer active; Epo expression from E11.5 onward is enhancer-independent, and is driven instead by basal promoter elements that provide a sufficient level of expression to support further erythropoietic differentiation.

  19. HIF-2α phosphorylation by CK1δ promotes erythropoietin secretion in liver cancer cells under hypoxia.

    PubMed

    Pangou, Evanthia; Befani, Christina; Mylonis, Ilias; Samiotaki, Martina; Panayotou, George; Simos, George; Liakos, Panagiotis

    2016-11-15

    Hypoxia inducible factor 2 (HIF-2) is a transcriptional activator implicated in the cellular response to hypoxia. Regulation of its inducible subunit, HIF-2α (also known as EPAS1), involves post-translational modifications. Here, we demonstrate that casein kinase 1δ (CK1δ; also known as CSNK1D) phosphorylates HIF-2α at Ser383 and Thr528 in vitro We found that disruption of these phosphorylation sites, and silencing or chemical inhibition of CK1δ, reduced the expression of HIF-2 target genes and the secretion of erythropoietin (EPO) in two hepatic cancer cell lines, Huh7 and HepG2, without affecting the levels of HIF-2α protein expression. Furthermore, when CK1δ-dependent phosphorylation of HIF-2α was inhibited, we observed substantial cytoplasmic mislocalization of HIF-2α, which was reversed upon the addition of the nuclear protein export inhibitor leptomycin B. Taken together, these data suggest that CK1δ enhances EPO secretion from liver cancer cells under hypoxia by modifying HIF-2α and promoting its nuclear accumulation. This modification represents a new mechanism of HIF-2 regulation that might allow HIF isoforms to undertake differing functions.

  20. Protection against malaria by anti-erythropoietin antibody due to suppression of erythropoiesis in the liver and at other sites.

    PubMed

    Tsubata, Shyunsuke; Ebe, Kazuto; Kawamura, Toshihiko; Ishimoto, Yuiko; Tomiyama-Miyaji, Chikako; Watanabe, Hisami; Sekikawa, Hiroho; Aoyagi, Yutaka; Abo, Toru

    2005-12-01

    We have previously reported that erythropoiesis commences in the liver and spleen after malarial infection, and that newly generated erythrocytes in the liver are essential for infection of malarial parasites as well as continuation of infection. At this time, erythropoietin (EPO) is elevated in the serum. In the present study, we administered EPO or anti-EPO antibody into C57BL/6 (B6) mice to modulate the serum level of EPO. When mice were infected with a non-lethal strain (17NXL) of Plasmodium yoelii (blood-stage infection of 10(4) parasitized erythrocytes per mouse), parasitemia continued for 1 month, showing a peak at day 17. Daily injection of EPO (200 IU/day per mouse) from day five to day 14 prolonged parasitemia, whereas injection of anti-EPO antibody (1.5 mg/day per mouse) every second day from day five to day 28 decreased it. Erythropoiesis was confirmed in the liver, spleen and bone marrow by the appearance of nucleated erythrocytes (TER119+). When anti-EPO antibody was injected by the same protocol into mice infected with a lethal strain (17XL) of P. yoelii, all mice showed decreased parasitemia and recovered from the infection. These results suggest that the use of anti-EPO antibody after malarial infection may be of therapeutic value in severe cases of malaria.