Disease relevance of EPO

• These results suggest that there is an ineffective erythroid response in the face of elevated EPO concentrations during bovine trypanosomiasis [1].
• Erythroid colony formation by polycythemia vera bone marrow in vitro. Dependence on erythropoietin [2].
• Because retinal ischemia is known to increase intracellular adenosine levels, which subsequently regulate hypoxia-inducible genes, such as vascular endothelial growth factor and erythropoietin, the role of adenosine and its receptor-mediated pathways has also been evaluated [3].
• When human anti-hsp70 antibody was added to ERBP-containing human hepatoma cell (Hep3B) lysates, the ERBP-Epo RNA complex was inhibited in an electrophoretic mobility band shift assay [4].
• Synthesis of erythropoietin (Epo), the glycoprotein hormone that regulates red blood cell formation, is induced in response to low oxygen stress (hypoxia), and is regulated at both transcriptional and post-transcriptional levels [4].

High impact information on EPO

• Role of endogenous prostaglandin E2 in erythropoietin production and dome formation by human renal carcinoma cells in culture [5].
• However, after the cultured cells became confluent, the levels of Ep in the incubated media showed a marked increase to 222.9 +/- 5.26 mU/ml (n = 5) at 30 d of cultivation [5].
• Studies were carried out on the role of endogenous prostaglandin E2 (PGE2) in erythropoietin (Ep) production and dome formation in primary monolayer cultures of a human renal carcinoma from a patient with erythrocytosis that has been serially transplanted into BALB/c athymic nude mice [5].
• In the plasma clot culture system both normal and polycythemia vera (PV) bone marrow cells respond to erythropoietin (Ep), giving rise to large numbers of colonies of erythroid cells [2].
• These results indicate that a portion of the NH2-terminal region of erythropoietin is exposed on the surface of the protein at some distance from the receptor-binding domain [6].

Biological context of EPO

• A bovine cDNA encoding erythropoietin (Epo) was isolated by polymerase chain reaction (PCR) amplification and screening of a bovine kidney cDNA library [7].
• In the present study, we investigated whether EPO can promote other cell proliferation and possible molecular mechanisms [8].
• Epo-secreting MSCs when administered as 'free' cells by subcutaneous or intraperitoneal injection, at the same cell dose, led to a significant - yet temporary - hematocrit increase to over 70% for 55+/-13 days [9].
• Interaction of erythropoietin RNA binding protein with erythropoietin RNA requires an association with heat shock protein 70 [4].
• We have previously described an Epo RNA binding protein (ERBP) which specifically binds to the 3'-untranslated region of Epo mRNA and is likely involved in the regulation of Epo mRNA stability [4].

Anatomical context of EPO

• Erythropoietin (EPO) stimulates the production of small erythroid cell stimulating factors (molecular weight <5 kDa) in cultures of bone marrow endothelial cells [10].
• Hemoglobin levels after four and eight weeks of EPO showed a significant relationship with circulating BFU-E at baseline (r = -0.873, r = -0.928, respectively) [11].
• These results indicate that EPO was eliminated by membrane adsorption only with some dialysis membranes [12].
• Erythropoietin (EPO), a hematopoietic factor, is required for normal erythrocyte developments, but it has been demonstrated to have many other functions, and its receptor is localized in other tissues [8].
• EPO restored the inhibition of the RAW264.7 and PC12 cell growth by fetal bovine serum (FBS) withdrawal in a dose dependent manner, but not that of other cell types tested [8].

Associations of EPO with chemical compounds

• The formation of EPO aggregates at later time points is probably induced by acidic cleavage products of the biodegradable polymer and requires further optimization of the ABA polymer composition [13].
• The bioactivity of EPO was measured in the assay by its stimulatory effect on 125I-deoxyuridine incorporation in spleen cells from phenylhydrazine-treated mice [1].
• Endotoxin, cortisol, T3, T4, insulin, estradiol, testosterone, and erythropoietin levels were not changed in a consistent direction by the CD treatment [14].
• Erythrotropin II stimulated thymidine incorporation and potentiated the action of erythropoietin in cultures of erythroid cells from fetal rat liver [15].
• Human erythropoietin (EPO) is an endogenously produced glycoprotein, which plays a key role in the erythropoiesis process [16].

Regulatory relationships of EPO

• The effect of recombinant human erythropoietin (Ep) and granulocyte colony-stimulating factor (G-CSF) on colony formation by human hemopoietic progenitors was examined in a methylcellulose culture system [17].

Other interactions of EPO

• In addition the EPO adsorptive rate, as well as that of beta 2-microglobulin (beta 2-MG), was greater with a PMMA membrane than with a PAN membrane [12].
• Erythropoietin at a concentration of 2 mU/mL was sufficient to increase erythropoiesis in the presence of these stromal cells, and the effect could be further enhanced in the presence of physiological concentrations of insulin-like growth factor II [18].
• Analysis of erythropoietin and erythropoietin receptor genes expression in cattle during acute infection with Trypanosoma congolense [19].
• The easy preparation of serum erythrotropin with specific activities higher than commercially available erythropoietin preparations will facilitate the study of the physiological role of this factor in vivo and in vitro [20].
• These techniques are applied to determining the degree of erythropoietin glycosylation, the degree of polyethylene glycol conjugation to RNase A and brain-derived neurotrophic factor, and the solution association states of these molecules [21].

Analytical, diagnostic and therapeutic context of EPO

• The expression of the bovine Epo gene in tissues from a severely anemic calf, bovine fetus and a healthy steer was analysed by a competitive RT-PCR method [7].
• The release profile was comparable to FITC-Dextran 40 kDa (FD 40) loaded microspheres in the initial release phase, while EPO release was leveling off at later time points [13].
• Different polymer compositions were studied for the microencapsulation of EPO using a modified double-emulsion process (W/O/W) [13].
• A bioassay was used to measure erythropoietin (EPO) concentrations in calves with haemorrhagic anaemia due to blood loss and in calves with anaemia due to Trypanosoma congolense infection [1].
• In addition, the cultured cells at each time period were incubated for 24 h in 5 ml of serum-free Eagle's MEM and the levels of PGE2 and Ep in the incubated media were measured via radioimmunoassay [5].

References