• 약학회지
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• 제47권6호
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• pp.422-431
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• 2003

The use of recombinant human erythropoietin (rhEPO), a stimulator of erythropoiesis, banned in sports because of the medical risk associated with thrombosis. Due to analytical difficulties to differentiate between natural human EPO (hEPO) and rhEPO, blood parameters of erythropoiesis such as contents of hemoglobin (cut-off value <17.5 g/d l for man, and < 16.0 g/dl for women), hematocrit and reticulocytes (cut-off value <2.0%) were measured to focus the misuse of rhEPO. We conducted anti-doping test for 122 blood samples of the World Cup athletes. The mean values of key parameters are as follows; 14.5$\pm$1.0 g/dl for hemoglobin, 41.7$\pm$2.8% for hematocrit, and 1.3$\pm$0.4% for reticulocyte. Blood sample was found to be stable up to 8 hours for the reticulocyte measurement. In addition, the soluble transferrin receptor and ferritin levels were measured by immunoassay methods using plasma samples (n=28) in which the mean value was 0.8$\pm$0.5 $\mu\textrm{g}$/$m\ell$ and 54.6$\pm$33.7 ng/$m\ell$, respectively. The results indicate that all samples tested were negative for the blood parameters of indirect anti-doping test for hEPO misuse. The statistical evaluation suggest that several other parameters such as red blood cell, mean corpuscular hemoglobin concentration, mean corpuscular volume, mean corpuscular hemoglobin and white blood cell could be considered as factors influencing hEPO function in addition to five parameters mentioned.

• 생명과학회지
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• 제9권2호
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• pp.201-206
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• 1999

본 연구는 정상 및 호흡곤란 신생아의 혈청내에 존재하는 nitric oxide(NO)의 생성을 관찰하고 erythropoietin (EPO)의 생성을 보기 위하여 정상 신생아 18명과 호흡곤란 신생아 16명으로부터 혈액을 채취하여 혈청내에서의 NO 및 EPO 생성량을 enzyme-linked immunosorbant assay법으로 측정하여 다음과 같은 결과를 얻었다. 1. 정상신생아의 혈청내 nitrite ion은 14.9$\pm$3.2 $\mu$M을 나타냈고 호흡곤란신생아군에서는 12.8$\pm$3.3 $\mu$M을 나타냄으로서 정상 대조군보다 호흡곤란군이 NO생성량이 낮음을 알 수 있었다. 2. 정상신생아의 혈청내 EPO는 16.2$\pm$3.4 mU/ml을 나타냈고 호흡곤란신생아군에서는 21.2 $\pm$5.4 mU/ml을 나타냄으로서 정상 대조군보다 호흡곤란군이 EPO생성량이 많음을 알 수 있었으며 통계학적으로 매우 유의한 차이를 나타냈다. 이상의 결과에서 호흡곤란증후군에서는 정상대조군에 비하여 NO생성이 대체적으로 저하되어 있음을 알 수 있었고 반대로 EPO의 생성은 증가되어 나타남으로서 EPO 상승에 따른 임상증상도 발현될 가능성이 있다하겠다.

• 한국가축번식학회지
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• 제27권4호
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• pp.299-307
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• 2003

The effects of additions/deletions in glycosylated residues of recombinant human EPO (rhEPO) produced in CHO-K1 on their secretion were examined. hEPO cDNA was amplified from human liver mRNA and cloned into the pCR2.1 TOPO. Using overlapping-extension site-directed mutagenesis method, glycosylation sites at 24th, 38th, 83rd, and 126th were respectively or accumulatively removed by substituting its asparagine (or serine) with glutamine. To add novel glycosylation sites, 69 and 105th leucine was mutated to asparagine. Mutant and wild type rhEPO constructs were cloned into the pcDNA3 expression vector with CMV promoter and transfected into CHO cell line, CHO-K1, to produce mutant rhEPO mutant rhEPO proteins. Enzyme-linked immunosorbant assay (ELISA) and Western analysis with monoclonal anti-EPO antibody were performed using supernatants of the cultures showing transient and stable expressions respectively. Addition of novel glycosylation reduced rhEPO secretion dramatically while deletion mutants had little effect except some double deletion mutants ($\Delta$24/83 and $\Delta$38/83) and triple mutant ($\Delta$24/38/83). This fact suggests that not single but combination of changes in glycosyl groups affect secretion of rhEPO in cell culture, possibly via changes in their conformations.

• The Korean Journal of Physiology and Pharmacology
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• 제16권4호
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• pp.281-285
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• 2012

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/microtubulea-ssociated 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.

• Clinical and Experimental Pediatrics
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• 제60권6호
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• pp.181-188
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• 2017

Purpose: Hypoxic-ischemic encephalopathy is a significant cause of neonatal morbidity and mortality. Erythropoietin (EPO) is emerging as a therapeutic candidate for neuroprotection. Therefore, this study was designed to determine the neuroprotective role of recombinant human EPO (rHuEPO) and the possible mechanisms by which mitogen-activated protein kinase (MAPK) signaling pathway including extracellular signal-regulated kinase (ERK1/2), JNK, and p38 MAPK is modulated in cultured cortical neuronal cells and astrocytes. Methods: Primary neuronal cells and astrocytes were prepared from cortices of ICR mouse embryos and divided into the normoxic, hypoxia (H), and hypoxia-pretreated with EPO (H+EPO) groups. The phosphorylation of MAPK pathway was quantified using western blot, and the apoptosis was assessed by caspase-3 measurement and terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Results: All MAPK pathway signals were activated by hypoxia in the neuronal cells and astrocytes (P<0.05). In the neuronal cells, phosphorylation of ERK-1/-2 and apoptosis were significantly decreased in the H+EPO group at 15 hours after hypoxia (P<0.05). In the astrocytes, phosphorylation of ERK-1/-2, p38 MAPK, and apoptosis was reduced in the H+EPO group at 15 hours after hypoxia (P<0.05). Conclusion: Pretreatment with rHuEPO exerts neuroprotective effects against hypoxic injury reducing apoptosis by caspase-dependent mechanisms. Pathologic, persistent ERK activation after hypoxic injury may be attenuateed by pretreatment with EPO supporting that EPO may regulate apoptosis by affecting ERK pathways.

• Clinical and Experimental Pediatrics
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• 제52권1호
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• pp.105-110
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• 2009

목적 : 신생 백서의 저산소 허혈 뇌손상에 있어서의 erythropietin (Epo) 투여의 손상 예방 효과와 보호 기전에 철 대사가 관여하는지를 조사하고자 하였다. 방 법 : 신생 백서를 암수 구별 없이 생후 7일째에 편측 온목동맥 결찰 후 산소 농도 8%인 환경에 2시간 노출시켜 저산소 허혈을 유도하였으며 저산소 노출 직후 Epo 5,000 u/kg를 복강내 투여하였다. 이들은 저산소 허혈 유도 전 투여한 생리식염수, 철, deferoxamine 등에 따라 Epo군, Iron+Epo군, Def+Epo군, Iron+ Def+Epo군, 대조군으로 나누어 저산소 허혈 유도 후 7일에 뇌손상 정도를 비교하였다. 결 과 : Epo 투여시 뇌손상의 빈도와 정도는 대조군에 비해 감소하였다. 뇌손상의 빈도와 손상 점수로 뇌손상 정도를 비교한 결과 철 투여는 Epo의 뇌손상 예방 효과를 감소시키지 않았다. Deferoxamine 투여는 Epo 단독 투여군에 비해 뇌손상의 빈도와 정도가 경감하였으나 통계적 유의성은 없었다. 결 론 : Epo는 저산소 허혈 뇌손상에 있어 뇌손상 보호 효과를 보인다. 철 투여는 뇌손상을 악화시키지 않았으나 deferoxamine 동시 투여는 Epo 단독 투여에 비해 뇌손상의 빈도와 손상 점수가 감소하여 뇌손상 보호 효과에 철 대사가 관여할 가능성을 제시하였다.

• Toxicological Research
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• 제13권1_2호
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• pp.139-147
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• 1997

Four-week toxicity of EPO(erythropoietin) was investigated using New Zealand White rabbits according to the established regulations of Korean National Institute of Safety Research. Rabbits were administered intravenously seven days per week for 28 days with dosage of 0, 80, 400 and 2000IU/kg B. W./day. Animals administered with EPO showed no significant changes of body weight, water consumption and feed consumption, and no clinical signs and death. They were not significantly different from the control group in hematological and serum biochemical analysis, urinalysis, prothrombin time, and partial thromboplastin time. In this study, we concluded that EPO had no toxic effect in the New Zealand White rabbits when they were administered intravenously below 2000IU/ kg B.W./ day for 28 days.

• Toxicological Research
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• 제13권1_2호
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• pp.127-130
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• 1997

Acute toxicity of EPO(Erythropoietin) was investigated using rats and beagle dogs according to Established Regulation of Korean National Institute of Safety Research (1994. 4. 14). Rats and beagle dogs were injected intravenously with dosages of 20000 IU/kg, 2000 IU/kg, 200 IU/kg, 20 IU/kg and 2 IU/kg. In animals injected with EPO, there were neither dead animals nor significant changes of body weights. In addition, no differences were found between control and treated groups in clinical signs and autopsy findings. Therefore $LD_50$ of EPO was considered to be higher than 20000 IU/ kg B. W. in rats and beagle dogs.

• Toxicological Research
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• 제13권1_2호
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• pp.131-138
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• 1997

Group of 40 male and 40 female Sprague-Dawley rats were given daily intravenous injections of different dosage of Erythropoietin (EPO), 80 IU/ kg/day (low dosage group), 400 IU/ kg/day (middle dosage group), or 2000 IU /kg/day (high dosage group)for 4 weeks by tail vein according to Established Regulation of Korean National Institute of Safety Research (1994. 4. 14). Appearance, behavior, mortality, and food consumption of rats of treated groups were not affected during the experimental periods. No significant EPO (erythropoietin)-related changes were found in urinalysts, eye examination, hematology, serum chemistry, and organ weight. No histopathological lesions were observed in both control and treatment groups. Our results strongly suggest that no toxic changes were found in rat treated intravenously with EPO (erythropoietin)for 4 weeks.

• Biomolecules & Therapeutics
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• 제4권4호
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• pp.330-333
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• 1996

Acute intravenous toxicities of rHu-EPO (recombinant human erythropoietin) were investigated in Sprague-Dawley rats. Seven days after administration of rHu-EPO, we examined the clinical signs, mortalities, body weight and etc. No clinical signs and mortalities of toxicity were observed in animals. Also, a significant change of body weights was not observed. These results suggest that LD$_{50}$ value was >25,000 unit/ kg in Sprague-Dawley rats and the acute intravenous toxicities of rHu-EPO were not significant.t.