OBJECTIVETo evaluate the effect of early application of recombinant human erythropoietin (rhEPO) on white matter development in preterm infants using fractional anisotropy (FA) of magnetic resonance diffusion tensor imaging (DTI).

METHODSA total of 81 preterm infants with gestational age ≤32 weeks, birth weight <1 500 g, and hospitalization within 24 hours after birth were randomly divided into rhEPO group (42 infants) and control group (39 infants). The infants in the rhEPO group were administered rhEPO, while those in the control group were given the same volume of normal saline. The preterm infants of both groups took examinations of head magnetic resonance imaging, diffusion-weighted imaging, and DTI at the corrected gestational age of 35-37 weeks. FA was calculated for the regions of interest in both groups.

RESULTSThere was no significant difference in the incidence of intracranial hemorrhage, periventricular leukomalacia, focal cerebral white matter damage (CWMD), and extensive CWMD between rhEPO and control groups (P>0.05). Compared with the control group, the rhEPO group showed higher FA values at the posterior limb of the internal capsule, the splenium of the corpus callosum, frontal white matter, and occipital white matter (P<0.05). There was no significant difference in FA values at the parietal white matter, thalamus, lenticular nucleus, and caudate nucleus between the two groups (P>0.05).

CONCLUSIONSEarly application of rhEPO has a neuroprotective effect on white matter development in preterm infants.

Diffusion Tensor Imaging ; Erythropoietin ; pharmacology ; Female ; Humans ; Infant, Newborn ; Infant, Premature ; Male ; Neuroprotective Agents ; pharmacology ; Recombinant Proteins ; pharmacology ; White Matter ; drug effects ; growth & development

OBJECTIVETo explore the impacts of erythropoietin on vascular endothelial growth factor receptor 2 (VEGFR2) by the extracellular signal-regulated kinase (ERK) signaling pathway in a neonatal rat model of periventricular white matter damage.

METHODSAll of postnatal day 4 rats were randomized into three groups: the sham group [without hypoxia-ischemia (HI)], the HI group (HI with saline administration), and the erythropoietin (EPO) group [HI with recombinant human erythropoietin (rh-EPO) administration]. Rat pups underwent permanent ligation of the right common carotid artery, followed by 6% O2 for 2 hours or sham operation and normoxic exposure. Immediately after the HI, rats received a single intraventricular injection of rh-EPO (0.6 IU/g body mass) or saline. ERK and phosphorylation-ERK were examined at 60 minutes and 90 minutes after operation, and VEGFR2 were detected at 2 and 4 days after operation by using Western blot.

RESULTSAt 60 minutes and 90 minutes after operation, the proteins of phosphorylation-ERK were significantly higher in HI rats than in the sham rats and significantly higher in HI+EPO rats than in the HI rats (P<0.05). Two days after operation, VEGFR2 was not significantly different between sham and HI rats. However, the proteins of VEGFR2 were increased after administration of rh-EPO (P<0.05). Four days after operation, the proteins of VEGFR2 were significantly higher in HI rats than in the sham rats and significantly higher in HI+EPO rats than in the HI rats (P<0.05).

CONCLUSIONEPO may regulate VEGFR2 expression by affecting the intracranial ERK signaling pathways.

Animals ; Animals, Newborn ; Disease Models, Animal ; Erythropoietin ; pharmacology ; Humans ; Hypoxia-Ischemia, Brain ; physiopathology ; MAP Kinase Signaling System ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; pharmacology ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism ; White Matter ; physiopathology

OBJECTIVETo explore the effect of recombinant human erythropoietin (rhEPO) on expression of brain-derived neurotrophic factor (BDNF) in different brain regions of aging rats.

METHODSForty male SD rats were randomized equally into negative control group, D-galactose group, EPO treatment group, and positive control group. Rat models of subacute aging were established by continuous subcutaneous injection of 5% D-galactose. Immunohistochemical staining was used to analyze the variation of BDNF expressions in different brain regions of the aging rats with different treatments.

RESULTSSignificant brain region-specific differences in BDNF expression were found among the rats in different groups. Compared with those in the negative control group, the numbers of BDNF-positive cells in the hippocampal CA1 region, CA3 region, dentate gyrus (DG) and frontal cortex were all decreased obviously in D-galactose group (P<0.05) but increased in both EPO group and the positive control group (P<0.05) without significant differences between the latter two groups. In the rats in the same group, the number of BDNF-positive cells varied markedly in different brain regions (P<0.05), and the expression level of BDNF was the highest in the frontal cortex followed by the hippocampal CA3 region and the dentate gyrus, and was the lowest in the hippocampal CA1 region.

CONCLUSIONTreatment with rhEPO enhances the expression of BDNF in rat neural cells, suggesting that rhEPO may protect the nervous system from aging by regulating the BDNF pathway.

Aging ; Animals ; Brain-Derived Neurotrophic Factor ; metabolism ; CA1 Region, Hippocampal ; metabolism ; CA3 Region, Hippocampal ; metabolism ; Dentate Gyrus ; metabolism ; Erythropoietin ; pharmacology ; Frontal Lobe ; metabolism ; Galactose ; Humans ; Male ; Neurons ; drug effects ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; pharmacology

OBJECTIVETo investigate the effect and mechanism of recombinant human erythropoietin (rhEPO) on angiogenesis in chronic ischemic porcine myocardium.

METHODSA ameroid constrictor was placed around the proximal circumflex branch of the left coronary artery in 12 Bama miniatures' swine artery by thoracoscopy. Electrocardiogram and coronary angiography were used to confirm the establishment of myocardial ischemia. The animals were divided into rhEPO treatment group (n = 6) and negative control group (n = 6). Treatment group received subcutaneous injection of rhEPO at 1, 3, 7, 14, 21 days, control group received saline. The expression of vascular endothelial growth factor (VEGF) in serum was assessed by ELISA. Ultrasonography and coronary angiography were assessed 28 days after therapy. Western blot was used to detect the expression of VEGF, phosphorylated protein kinase B (p-Akt) and phosphorylated extracellular signal regulated kinases (p-Erk). The degree of angiogenesis was assessed by immunohistochemical analysis.

RESULTSSerum VEGF rose significantly in both control and treatment groups, peaking at 3 days and then returning to the near-baseline level at 28 days, but the two groups showed no significant difference at each time point (P > 0.05). Echocardiographic measurements showed that the left ventricular systolic function of animals in treatment group increase significantly after rhEPO therapy. the expression levels of VEGF, p-Akt and p-Erk had markedly increased, which resulted in a 2.5-fold increased of VEGF, 1.1-fold increased of p-Akt, 1.5-fold increased of p-Erk (t = 37.721, 10.907, 12.957, all P = 0.000). there were significant increase in capillary density and arteriole density in the two groups ((944 ± 98) %/mm² vs. (569 ± 102) %/mm², (73 ± 13) %/mm² vs. (45 ± 10) %/mm², t = 4.214, 2.869, P = 0.016, 0.023).

CONCLUSIONSrhEPO can promote angiogenesis and arteriogenesis and improve the left ventricular systolic function in porcine model of chronic myocardial ischemia. The potential mechanism is to up-regulated the expression of p-Akt and p-Erk.

Animals ; Disease Models, Animal ; Epoetin Alfa ; Erythropoietin ; pharmacology ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Humans ; Male ; Myocardial Ischemia ; drug therapy ; metabolism ; pathology ; Neovascularization, Physiologic ; drug effects ; Proto-Oncogene Proteins c-akt ; metabolism ; Recombinant Proteins ; pharmacology ; Swine ; Swine, Miniature ; Vascular Endothelial Growth Factor A ; metabolism

OBJECTIVETo evaluate the clinical effects of the early use of recombinant human erythropoietin (rhEPO) on the neurointelligence development in very low birth weight infants (VLBWI).

METHODSSeventy-eight VLBWI were divided into rhEPO treatment group (n=35) and control group (n=43) according to the choice of their parents. Neonatal behavioral neurological assessment (NBNA) was performed at 40 weeks of corrected gestational age. The Gesell Developmental Schedules were used for neurodevelopmental evaluation at 3, 6, and 12 months of corrected age. The abnormal rates of auditory brainstem response (ABR) and cranial ultrasound were evaluated at 6 months of corrected age.

RESULTSThe rhEPO treatment group had significantly higher NBNA scores at 40 weeks of corrected gestational age than the control group (P<0.05). The adaptability at 3 months of corrected age, the gross motor, adaptability, and sociability at 6 months, and the gross motor, adaptability, fine motor, sociability, and language at 12 months were significantly better in the rhEPO treatment group than in the control group (P<0.05). The abnormal rates of ABR and cranial ultrasound in the rhEPO treatment group were significantly lower than in the control group at 6 months of corrected age (P<0.05).

CONCLUSIONSEarly use of rhEPO can promote the early recovery of neurological symptoms and improve the cognitive, motor, and language abilities in VLBWI due to its protective effects on the nervous system.

Child Development ; drug effects ; Erythropoietin ; pharmacology ; Evoked Potentials, Auditory, Brain Stem ; Female ; Humans ; Infant, Newborn ; Infant, Very Low Birth Weight ; growth & development ; Intelligence ; drug effects ; Male ; Nervous System ; drug effects ; growth & development ; Recombinant Proteins ; pharmacology

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.
Alanine Transaminase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Blood Urea Nitrogen ; Blotting, Western ; Creatinine ; blood ; Endotoxins ; Erythropoietin ; administration & dosage ; genetics ; pharmacology ; Injections, Intravenous ; Kidney ; drug effects ; metabolism ; ultrastructure ; Lipopolysaccharides ; Liver ; drug effects ; metabolism ; ultrastructure ; Lung ; drug effects ; metabolism ; ultrastructure ; Male ; Microscopy, Electron, Transmission ; Multiple Organ Failure ; blood ; chemically induced ; prevention & control ; NF-kappa B ; metabolism ; Phosphorylation ; drug effects ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Rats, Wistar ; Recombinant Proteins ; administration & dosage ; pharmacology ; Tumor Necrosis Factor-alpha ; blood

OBJECTIVETo study the effect of erythropoietin (EPO) on the activities of antioxidant enzymes, namely catalase (CAT) and glutathione peroxidase (GSH-Px) in the brain tissues of aged rats.

METHODSThirty SD rats were randomly divided into normal control, aging model, and recombinant human erythropoietin (rhEPO) treatment groups (n=10). Morris water maze was used to compare the behavioral indexes. The rats were then sacrificed to observe Nissl bodies in the hippocampal neurons with Nissl staining and test the activities of CAT and GSH-Px in the brain tissues.

RESULTSCompared with the control group, the aging rats showed significantly deteriorated learning and memory abilities (P<0.05), which were improved obviously by rhEPO treatment (P<0.05). The number of Nissl bodies in the neurons was reduced in the aging rats compared with that in the control group, and rhEPO treatment increased the number of Nissle bodies but failed to restore the control level. The aging rats also showed significantly lowered activities of CAT and GSH-Px in the brain tissue (P<0.05), which were increased significantly after rhEPO treatment (P<0.05).

CONCLUSIONEPO can enhance the activities of the antioxidant enzymes in the brain tissues of aged rats to increase the antioxidant capacity and produces an anti-aging effect.

Aging ; Animals ; Brain ; enzymology ; Catalase ; metabolism ; Epoetin Alfa ; Erythropoietin ; pharmacology ; Glutathione Peroxidase ; metabolism ; Learning ; drug effects ; Male ; Memory ; drug effects ; Nissl Bodies ; drug effects ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; pharmacology

BACKGROUNDIn addition to hematopoietic effect, the erythropoietin is known as a multifunctional cytokine with anti-fibrosis and organ-protective activities. The purpose of this study was to evaluate the effect of recombinant human erythropoietin (rhEPO) on hepatic fibrosis and hepatic stellate cells (HSCs).

METHODSCarbon tetrachloride (CCl(4)) induced hepatic fibrosis mice models were used for in vivo study and HSCs line for in vitro study. CCl(4) and rhEPO (0, 200 or 1000 U/kg) was injected intraperitoneally in BALB/c mice three times a week for 4 weeks. Immunohistochemistry and immunoblotting were performed to evaluate expressions of transforming growth factor-β1 (TGF-β1), α-smooth muscle actin (α-SMA), and fibronectin in explanted liver. Immunoblotting of α-SMA, phophorylated Smad-2 and Smad-2/3 was performed in HSCs treated with TGF-β1 and/or rhEPO.

RESULTSExpressions of TGF-β1, α-SMA, and fibronectin were increased in CCl(4) injected mice livers, but significantly attenuated by co-treatment with CCl(4) and rhEPO. Co-treatment of rhEPO markedly suppressed fibrosis in Masson's trichrome compared with treatment of only CCl(4). TGF-β1 increased phosphorylated α-SMA, Smad-2 expressions in HSCs, which were decreased by rhEPO co-treatment.

CONCLUSIONSTreatment of rhEPO effectively suppressed fibrosis in CCl(4)-induced liver fibrosis mice models. Anti-fibrosis effect of rhEPO could be related to inhibition of TGF-β1 induced activation of HSCs.

Animals ; Carbon Tetrachloride ; toxicity ; Cells, Cultured ; Erythropoietin ; pharmacology ; therapeutic use ; Fibronectins ; analysis ; Hepatic Stellate Cells ; drug effects ; Liver Cirrhosis, Experimental ; metabolism ; prevention & control ; Male ; Mice ; Mice, Inbred BALB C ; Recombinant Proteins ; pharmacology ; Smad2 Protein ; metabolism ; Transforming Growth Factor beta ; antagonists & inhibitors ; physiology

To study whether recombinant human erythropoietin (rhEPO) reduces neuronal apoptosis through inhibiting over-expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in nucleus induced by brain ischemia/reperfusion in rats, 48 adult Sprague-Dawley rats were randomly divided into 3 groups: sham, saline and EPO groups. Animal models of brain ischemia/reperfusion were established by middle cerebral artery occlusion in rats. The effects of EPO on the sizes of ischemia tissue were observed by TTC staining. The over-expression of GAPDH in nucleus was detected by Hoechst-33258 and anti-GAPDH antibody double staining. The neuronal apoptosis in penumbral was detected by Nissl's staining and Hoechst-33258 immunofluorescence, respectively. The results showed that rhEPO treatment (3 000 U/kg, three times daily, i.p.) apparently reduced the sizes of infarct brain tissue in ischemia/reperfusion rats. rhEPO inhibited over-expression of GAPDH in nucleus of apoptotic neurons. In the meantime rhEPO decreased the number of apoptotic neurons in ischemia/reperfusion rats. These results suggest that rhEPO may induced reduction of neuronal apoptosis in penumbra may be through inhibiting over-expression of GAPDH in nucleus of apoptotic neurons induced by ischemia/reperfusion. Reduction of GAPDH over-expression in nucleus may play a pivotal role in EPO inhibiting neuronal apoptosis in cerebral ischemia/reperfusion rats, providing experimental evidence for EPO neuro-protecting effects against ischemia/reperfusion.
Animals ; Apoptosis ; Brain ; enzymology ; pathology ; Brain Ischemia ; pathology ; Erythropoietin ; pharmacology ; Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating) ; metabolism ; Humans ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; pharmacology ; Reperfusion Injury ; pathology

This study was conducted to investigate the effects of erythropoietin (Epo) on both acute and chronic limb ischemia (ALI and CLI) and to evaluate the differences in mechanisms according to the method of Epo administration. Hindlimb ischemia was made in BALB/c mice with femoral artery ligation. The mice were divided into four groups: Group 1 (control, no treatment), Group 2 (ALI, early multiple doses), Group 3 (ALI, early single high dose), Group 4 (CLI, late multiple doses). Blood flow ratio significantly increased in Group 2 in 4 weeks. Expression of pAkt and Erythropoietin receptor were significantly higher in Group 2 on postoperative day (POD) 7. The number of CD31- and vascular endothelial growth factor-positive cells were significantly higher in Group 2 on POD 7 and 56. Group 3 and 4 showed a tendency of higher cell counts than the control. The early sustained Epo was effective in improving blood flow through angiogenesis. In chronic phase, weekly multiple dosing of Epo induced angiogenesis, however, the blood flow ratio did not increase significantly. The results of this study suggest that Epo administration during the acute phase followed by maintenance for several days may be important for increasing blood flow and angiogenesis.
Acute Disease ; Animals ; Chronic Disease ; Erythropoietin/*pharmacology ; Hindlimb/*blood supply ; Ischemia/*metabolism/pathology ; Laser-Doppler Flowmetry ; Male ; Mice ; Mice, Inbred BALB C ; Neovascularization, Physiologic/drug effects ; Proto-Oncogene Proteins c-akt/metabolism ; Receptors, Erythropoietin/metabolism ; Recombinant Proteins/pharmacology ; Vascular Endothelial Growth Factor A/metabolism