Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The risks inherent in the use of homologous blood products have increased efforts toward identifying alternatives to transfusion. We have previously shown that the administration of recombinant human erythropoietin (rhEpo) enhances the erythropoietic response to acute blood loss. Recombinant human interleukin-3 (rh-IL-3) is a hematopoietic growth factor that has been shown to act synergistically with rhEpo in accelerating erythropoiesis in vitro. The purpose of this study in a primate model was to determine if the administration of rhIL-3 in combination with rhEpo could augment the erythropoietic response to acute blood loss more than rhEpo therapy alone. Twenty-four adult male baboons were randomized into four groups. The induction of acute normovolemic anemia to a hematocrit of 20% was accomplished via exchange-transfusion with 6% hetastarch. The groups were then treated for 7 consecutive days with the following growth factors: group I (n = 7), no growth factors; group II (n = 5), rhIL-3 alone (100 micrograms/kg/d); group III (n = 6), rhEpo alone (1000 U/kg/d); group IV (n = 6), rhEpo (1000 U/kg/d) plus rhIL-3 (100 micrograms/kg/d). All animals received folate, vitamin B12, and intravenous iron-dextran immediately following the exchange-transfusion. Response to therapy was monitored for 35 days. There were no adverse reactions following growth factor administration. The analysis of erythropoietic rates between study days 1 through 11, as determined via linear regression analysis, revealed that hematocrits increased significantly faster in the groups receiving rhEpo compared to controls. The administration of rhIL-3, however, did not increase the rate of erythropoiesis when compared to controls, nor did it augment response when added to the rhEpo regimen. The results of this study demonstrate that the administration of rhIL-3 alone had no significant effect on erythropoiesis in this setting of acute blood loss. Further, despite promising in vitro data, rhIL-3 provided no additional stimulation of erythropoiesis in animals receiving rhEpo. Nevertheless, the study confirms that the pharmacologic acceleration of erythropoiesis by rhEpo alone remains an attractive alternative to homologous transfusion.
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PMID:Effects of recombinant human erythropoietin and interleukin-3 on erythropoietic recovery from acute anemia. 840 28

Erythropoietin is the only hematopoietic growth factor that behaves like a hormone. Produced in the kidneys and the liver, erythropoietin interacts with erythroid progenitor cells in the bone marrow to promote their proliferation and maintain their viability. Erythropoietin production is regulated at the level of its gene by tissue oxygenation; hypoxia or anemia stimulates erythropoietin production, and erythrocytosis suppresses it, but never completely. The plasma erythropoietin concentration reflects erythropoietin production and can be used to define erythropoietin-deficient states in which anemia may be amenable to correction by administration of recombinant human erythropoietin.
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PMID:Recombinant erythropoietin. 847 46

Erythropoietin (EPO) is the hematopoietic growth factor that regulates red cell production. There is a direct relationship between its secretion and tissue hypoxia. Above sea level, oxygen concentration diminishes. This causes an increase of hemoglobin and hematocrit; this effect could be the consequence of higher EPO levels. Currently, evaluation of baseline serum EPO levels is very important in the differential diagnosis of anemia and erythrocytosis. The purpose of the present work was to report the EPO levels on a group of healthy blood donors living in Mexico City, 2,240 m above sea level. Two-hundred twenty blood donors were selected to measure serum EPO; there were 168 males and 52 females. Median EPO levels of the entire population were 7.5 mU/mL (percentile interval, PI, 1-18). Median EPO levels were 7.6 (PI 1-18) and 7.5 (PI 1-16.9) for men and women, respectively. We did not find differences in serum EPO levels among previous reports in other populations and the values determined in this study.
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PMID:[Blood erythropoietin levels in healthy subjects studied in the valley of Mexico]. 950 69

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.
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PMID:Biology of erythropoietin. 979 57

The problems of immunologic adaptation during the transitional period from intra- to extrauterine life are responsible for the physiologic immaturity of the immune function in newborn infants. In preterm neonates the immunodeficiency is more severe and prolonged and is associated with a higher incidence of infections and sepsis. Furthermore, due to immaturity of the hematologic system, anemia, thrombocytopenia, and neutropenia are frequently observed in very low birth weight infants. The dysregulation of cytokine and hematopoietic growth factor synthesis is an important contributory factor to the complex deficiency of immunologic and hematologic function in the neonate and may explain the reduced incidence of acute graft-versus-host disease observed after cord blood transplantation in children. Human milk is a rich source of most of the cytokines that are reduced in the neonate. Granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, and erythropoietin are currently under evaluation in newborn infants with septic neutropenia or anemia of prematurity.
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PMID:Hematopoietic growth factor levels in term and preterm infants. 1022 41

Despite considerable progress in recent years in the understanding of the biology of multiple myeloma (MM), this disease remains incurable, although many new therapeutic approaches are under evaluation. The rapid development of recombinant technologies has permitted the production of large amounts of cytokines and growth factors, favoring the use of biotherapies also in this disease. Among these products, the interferons have been the most extensively used in clinical trials, giving the most promising results especially in the setting of minimal residual disease, as maintenance therapy after response to conventional therapies, or to high dose chemotherapies followed by bone marrow (BM) or peripheral blood stem cell (PBSC) transplantation. However, more recently, a large number of cytokines and growth factors have been introduced in the clinical practice. Data of the use of erythropoietin have consistently demonstrated the role of this growth factor in ameliorating the grade of anemia as well as the quality of life of those MM patients whose disease is complicated by the presence of a severe or moderate anemia. Using hematopoietic growth factor in the mobilization of PBSC, the quantity of progenitor cells in the peripheral blood increased and the hematological toxicity of chemotherapy could be reduced. Despite the large amount of experimental data indicating a role for interleukins, as IL-2 and IL-6, in controlling tumor growth, there are only few clinical studies dealing with their use in MM. Results show that they arrest tumor progression rather than aid tumor regression, for this reason it appears that IL-2 and anti IL-6 antibodies should be investigated as maintenance therapy, in MM patients responding to chemotherapy. In the future it will be necessary to clarify for MM patients the role of other cytokines such as IL-1 beta and TNF alpha. A possible strategy to improve the clinical outcome of MM patients is to prevent the regrowth of residual tumor cells by establishing adoptive immunity at the stages of minimal residual disease previous obtained using chemotherapy. To this end a possible strategy is to induce an immune response against residual tumor cells by passive (using monoclonal antibodies) or active (using the idiotype expressed by malignant cells) immunotherapy.
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PMID:[The role of biotherapy in multiple myeloma]. 1107 35

This review focuses on the role of interleukin (IL)-12, a proinflammatory cytokine with pleiotropic effects as a potent immunoregulatory molecule and hematopoietic growth factor, in infection with Plasmodium parasites, the causative agents of malaria. IL-12 has been demonstrated to have profound effects on the immune response to blood-stage malaria, to induce protection, and to alleviate malarial anemia. In combination with an anti-malarial drug, IL-12 is effective in an established malaria infection. This cytokine also has potent immune effects as a malaria vaccine adjuvant. However, IL-12 can also mediate pathology during blood-stage malaria.
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PMID:Modulation of host responses to blood-stage malaria by interleukin-12: from therapy to adjuvant activity. 1122 54

Erythropoietin (EPO), granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage stimulating factor (GM-CSF) are currently licensed for use in cancer patients and play a significant role in the management of anemia and neutropenia following myeloblative chemotherapy. EPO was the first recombinant hematopoietic growth factor to be used clinically after a number of clinical trials which demonstrated its effectiveness in treating mild to moderate cancer-associated anemia with or without concomitant chemotherapy (particulary cisplatin). An extensive research has been made for the improvement of the quality of life with EPO therapy, however, when formally assessed, variable effects of this important treatment have been observed. Recently, EPO has been shown to significantly accelerate hematopoietic reconstitution after peripheral blood stem cell transplantation (PBSCT) resulting in reduced infection rates. Both, G-CSF and GM-CSF have been shown, in numerous trials, to shorten the period of chemotherapy-induced neutropenia, with reduction in attendant morbidity and to mobilize PBSC. In addition, administration of both cytokines after PBSCT significantly reduced the use of antibiotics and duration of hospitalization suggesting an economic benefit. The narrower therapeutic window of GM-CSF at higher doses accounts for the fact that it is used much less frequently than G-CSF. To date, none of the growth factors used clinically has been shown to stimulate thrombopoiesis. Although thrombopoietin (TPO) has been found to induce megakaryocyte differentiation in vitro, it is unlikely to enter routine clinical use for treatment of post-chemotherapy thrombocytopenia, since results of clinical trials are not very encouraging, mainly because TPO is difficult to schedule and platelet aggregation may occur. Recently, innovative chimeric growth factor receptor agonists have been synthesized. Synthokine (SC-55494) (a high-affinity human IL-3 receptor ligand analog), myelopoietin (MPO) (activates human IL-3 and G-CSF receptors) and promegapoietin (PMP) (stimulates the human IL-3 and c-mpl receptors) were found to be multilineage hematopoietic growth factors and are currently undergoing clinical trials. Preliminary results suggest that these compounds may have a major impact on the management of myeloablative chemotherapy because of their ability to enhance platelet recovery in addition to their neutrophil restorative activity.
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PMID:Human hematopoietic growth factors: old lessons and new perspectives. 1132 88

People with advanced HIV infection and anemia are at greater risk of complications from red blood cell transfusions than those who are not HIV-positive. The advent of synthetic hematopoietic growth factors has provided an alternative for managing anemia. Epoetin alfa is a recombinant human erythropoietin (rHuEpo), which is an example of a hematopoietic growth factor, and it was approved for treatment of anemia in HIV-positive patients in 1991. The origin and makeup of rHuEpo are examined, as are the effects of regulating its levels with different drug treatments. Because the effects of blood transfusions to raise hematocrit levels are short-lived, fewer transfusions are being performed in favor of using rHuEpo. Also, side effects of anemia, as well as statistics of survival are somewhat improved by this treatment. Several possible causes for anemia in HIV-infected patients are cited, including atypical mycobacteria, toxoplasma gondii, and side effects resulting from drug therapy. Additional studies are examined.
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PMID:Recombinant human erythropoietin for HIV-related anemia. 1136 57

The myelodysplastic syndromes (MDS) are clonal hematological disorders characterized by ineffective hematopoiesis manifested by anemia, neutropenia, thrombocytopenia or a combination. Correction of these cytopenia is a priority in MDS without excess of blasts. Treatment of anemia depends mainly on erythrocyte transfusions. However with the ability of recombinant human hematopoietic growth factor many trials have been promoted. In vitro, erythroid progenitors from MDS patients are able to differentiate but they require much higher concentrations of erythropoietin than normal progenitors. Trials using rHu-Epo alone are disappointing. Combining rHu-Epo and rHu-G-CSF induces more encouraging results showing a synergistic effect particularly clear in sideroblastic anemia. Patients with low endogenous Epo level and low transfusion need are more likely to respond. Clinician should be able in the future to identify MDS patients with a chance of reversal of anemia or transfusion dependency.
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PMID:[The place of growth factors in the treatment of myelodysplastic syndromes]. 1208 72


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