losartan-potassium and Brain-Infarction

Analysis of published data indicates that erythropoietin plays an important role in regulation of brain tolerance to impact of ischemia-reperfusion. This cytokine is involved in ischemic preconditioning of the brain and can mimic the phenomenon of preconditioning and postconditioning. However, it is unclear whether endogenous erythropoietin takes part in postconditioning of the brain. It is established that erythropoietin inhibits apoptosis of neurons after ischemia-reperfusion. It was found that erythropoietin could stimulate regeneration of the brain after ischemia. Signaling mechanism of neuroprotective action of erythropoietin is well studied but there are very little data on the mechanism of erythropoietin-induced neurogenesis and neoangiogenesis. It is unknown whether erythropoietin can exhibit infarct-limiting effect in humans and stimulate neurogenesis and neoangiogenesis in patients after insult.

Topics: Animals; Apoptosis; Brain; Brain Infarction; Erythropoietin; Ischemic Preconditioning; Male; Neovascularization, Physiologic; Neurons; Regeneration; Reperfusion Injury; Stroke

Extremely high doses of erythropoietin (EPO) has been used for neuroprotection in ischemia-reperfusion brain injury to deliver sufficient amounts of EPO across the blood-brain barrier (BBB); however, harmful outcomes were observed afterward. We aimed to test the ability of HBHAc (heparin-binding haemagglutinin adhesion c), an intracellular delivery peptide for macromolecules, as an EPO carrier across the BBB. The cellular internalization and transcytosis ability of HBHAc-modified EPO (EPO-HBHAc) were evaluated in bEnd.3 cells and in the bEnd.3/CTX TNA2 co-culture BBB model, respectively. Subsequently, the NMDA-induced-toxicity model and ischemia-reperfusion rat model were used to understand the neuronal protective activity of EPO-HBHAc. The biodistribution of EPO-HBHAc was demonstrated in rats by the quantification of EPO-HBHAc in the brain, plasma, and organs by ELISA. Our results demonstrate that EPO-HBHAc exhibited significantly higher cellular internalization in dose- and time-dependent manners and better transcytosis ability than EPO. In addition, the transported EPO-HBHAc in the co-culture transwell system maintained the neuronal protective activity when primary rat cortical neurons underwent NMDA-induced toxicity. The calculated cerebral infarction area of rats treated with EPO-HBHAc was significantly reduced compared to that of rats treated with EPO (29.9 ± 7.0% vs 48.9 ± 7.9%) 24 h after occlusion in 3VO rat experiments. Moreover, the EPO amount in both CSF and damaged cortex from the EPO-HBHAc group was 4.0-fold and 3.0-fold higher than the EPO group, respectively. These results suggest that HBHAc would be a favorable tool for EPO brain delivery and would further extend the clinical applications of EPO in neuroprotection.

Topics: Animals; Blood-Brain Barrier; Brain Infarction; CHO Cells; Cricetinae; Cricetulus; Drug Carriers; Drug Development; Erythropoietin; Male; Neuroprotective Agents; Plasmids; Rats; Rats, Wistar; Tissue Distribution

We examined the preventive effect of human recombinant erythropoietin (HrEPO) on nitric oxide (NO)-mediated toxicity to neurons and cysteine protease release into cytoplasm, which is attributed to neuronal death in brain ischemia. Focal cerebral ischemia was induced by permanent occlusion of middle cerebral artery in two sets of rat. The first set was used to monitor NO concentration and cathepsin activity, while the second was used for histological examination with hematoxylin and eosin, and TUNEL staining. A group in both set was administered human recombinant erythropoietin (HrEPO). NO content, cathepsins B and L activity increased significantly in the post-ischemic cerebral tissue (p<0.05). HrEPO treatment reduced NO concentration and cathepsin activity to control level (p>0.05). A significant increase in the number of necrotic and apoptotic neurons was observed in the post-ischemic cerebral cortex (p<0.05). HrEPO treatment was markedly lowered both of these (p<0.05). It is concluded that HrEPO prevents neuronal death by protecting neuronal liposomes from NO-mediated toxicity and suppressing the release of cathepsins.

Topics: Animals; Brain Infarction; Brain Ischemia; Cathepsin B; Cathepsin L; Cell Death; Disease Models, Animal; Erythropoietin; Humans; Nerve Degeneration; Neuroprotective Agents; Rats; Rats, Sprague-Dawley

This study tested the superiority of combined cyclosporine A (CsA)-erythropoietin (EPO) therapy compared with either one in limiting brain infarction area (BIA) and preserving neurological function in rat after ischemic stroke (IS).. Fifty adult-male SD rats were equally divided into sham control (group 1), IS plus intra-peritoneal physiological saline (at 0.5/24/48 h after IS) (group 2), IS plus CsA (20.0 mg/kg at 0.5/24h, intra-peritoneal) (group 3), IS plus EPO (5,000IU/kg at 0.5/24/48h, subcutaneous) (group 4), combined CsA and EPO (same route and dosage as groups 3 and 4) treatment (group 5) after occlusion of distal left internal carotid artery.. BIA on day 21 after acute IS was higher in group 2 than in other groups and lowest in group 5 (all p < 0.01). The sensorimotor functional test showed higher frequency of left turning in group 2 than in other groups and lowest in group 5 (all p < 0.05). mRNA and protein expressions of apoptotic markers and number of apoptotic nuclei on TUNEL were higher in group 2 than in other groups and lowest in group 1 and 5, whereas the anti-apoptotic markers exhibited an opposite trend (all p < 0.05). The expressions of inflammatory and oxidized protein were higher in group 2 than in other groups and lowest in group 1 and 5, whereas anti-inflammatory markers showed reversed changes in group 1 and other groups (all p < 0.05). The number of aquaporin-4+ and glial fibrillary acid protein+ stained cells were higher in group 2 as compared to other groups and lowest in groups 1 and 5 (all p < 0.01).. combined treatment with CsA and EPO was superior to either one alone in protecting rat brain from ischemic damage after IS.

Topics: Animals; Apoptosis; Aquaporin 4; Brain Infarction; Cell Nucleus; Cyclosporine; Cytochromes c; Drug Therapy, Combination; Erythropoietin; Gene Expression Regulation; Glial Fibrillary Acidic Protein; In Situ Nick-End Labeling; Inflammation; Male; Oxidative Stress; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Rats; Rats, Sprague-Dawley; Recovery of Function; RNA-Binding Proteins; RNA, Messenger; Stroke; Transcription Factors

Erythropoietin (EPO) exhibits diverse cellular functions, including neurotrophic, anti-oxidant, anti-apoptotic, and anti-inflammatory effects in non-hematopoietic tissues. This study evaluated whether bone marrow mesenchymal stromal cells (MSCs) transduced with the EPO gene (EPO-MSCs) promoted neural cell survival and improved neurological deficits caused by ischemic stroke. EPO-MSCs stably produced high levels of EPO (10IU/ml) without any alteration of their mesenchymal phenotype. Both EPO transduction and treatment with 10 international units (IU) of recombinant human EPO (rhEPO) provided protection from H(2)O(2)-induced oxidative injury in human bone marrow mesenchymal stromal cells and in SH-SY5Y cells. EPO-MSCs were more protected than were MSCs treated with 10IU rhEPO (10U-MSCs). We also found that the expression of the neurotrophic factors BDNF, PD-ECGF, HGF, SDF-1alpha, and TGF-1beta increased in EPO-MSCs, while only BDNF and TGF-1beta increased in 10U-MSCs. Implantation of EPO-MSCs in an animal model of ischemic stroke significantly improved neurological function and decreased infarct volumes without affecting hematocrit level. An evaluation of the brain tissue 21days after implantation showed that EPO and phosphorylated Akt (a downstream mediator of EPO) increased only in brains implanted with EPO-MSCs. Transduction of the EPO gene into MSCs induced secretion of EPO and various trophic factors that may provide excellent neuroprotective effects in both in vitro and in vivo models of ischemic stroke.

Topics: Animals; Antigens, CD; Brain Infarction; Caspase 3; Cell Death; Cell Line; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Erythropoietin; Flow Cytometry; Gene Expression Regulation; Green Fluorescent Proteins; Humans; Hydrogen Peroxide; Infarction, Middle Cerebral Artery; Lentivirus; Magnetic Resonance Imaging; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Nerve Growth Factors; Nervous System Diseases; Rats; Statistics, Nonparametric; Tetrazolium Salts; Thiazoles; Transduction, Genetic

The impact of epoetin beta (recombinant human erythropoietin) on brain infarction area (BIA) and neurological status in a rat model of acute ischemic stroke (IS) induced by distal left internal carotid artery occlusion was investigated.. Adult male Sprague-Dawley rats (n = 30) were categorized into group 2 (IS only) and group 3 (IS plus intraperitoneal erythropoietin 5000 IU/kg at 0, 12, and 24 hours after IS). Healthy Sprague-Dawley rats (n = 10) served as group 1.. Analysis of brain tissues showed larger BIA in group 2 than in group 3 (P < 0.001). Corner test identified highest frequency of left turn in group 2 (P < 0.05). The mRNA expressions of Bax, caspase 3, interleukin 18, toll-like receptor 4, and plasminogen activator inhibitor 1 were highest, whereas Bcl-2 was lowest in group 2 (P < 0.05). Lower CXCR4 and stromal cell-derived factor 1 expressions were noted in group 2 than in group 3 (P < 0.01). Immunohistofluorescence staining showed lower expressions of CXCR4, stromal cell-derived factor 1, von Willebrand factor, and doublecortin with higher number of apoptotic nuclei in group 2 than in group 3 (P < 0.001). Immunohistochemical staining demonstrated lower cellular proliferation and number of small vessels with higher glial fibrillary acid protein expression in group 2 than in group 3 (P < 0.01).. Erythropoietin significantly limited BIA and improved sensorimotor dysfunction after acute IS.

Topics: Acute Disease; Animals; Apoptosis; Brain Infarction; Brain Ischemia; Disease Models, Animal; Doublecortin Protein; Encephalitis; Erythropoietin; Hematinics; Humans; Male; Neovascularization, Physiologic; Neurogenesis; Oxidative Stress; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Recovery of Function

Deferoxamine (DFO) and erythropoietin (EPO) have each been shown to provide neuroprotection in neonatal rodent models of brain injury. In view of the described anti-oxidative actions of DFO and the anti-apoptotic and anti-inflammatory effects of EPO, we hypothesized that the combination of DFO and EPO would increase neuroprotection after neonatal hypoxic-ischemic brain injury as compared to single DFO or EPO treatment. At postnatal day 7 rats underwent right common carotid artery occlusion followed by a 90-min exposure to 8% oxygen. Rats were treated intraperitoneally with DFO (200mg/kg), recombinant human EPO (1 kU/kg), a combination of DFO-EPO or vehicle at 0, 24 and 48 h after hypoxia-ischemia (HI) and were sacrificed at 72 h. DFO-EPO administration reduced the number of cleaved caspase 3-positive cells in the ipsilateral cerebral cortex. Early neuronal damage was assessed by staining for microtubuli-associated protein (MAP)-2. In our model 63+/-9% loss of ipsilateral MAP-2 was observed after HI, indicating extensive brain injury. DFO, EPO or DFO-EPO treatment did not improve neuronal integrity as defined by MAP-2. Cerebral white matter tracts were stained for myelin basic protein (MBP), a constituent of myelin. Hypoxia-ischemia strongly reduced MBP staining which suggests white matter damage. However, DFO, EPO and DFO-EPO treatment had no effect on the loss of MBP staining. Finally, HI-induced loss of striatal tyrosine hydroxylase staining was not attenuated by DFO, EPO or DFO-EPO. Although DFO-EPO treatment reduced the number of cleaved caspase 3(+) cells, treatment with DFO, EPO, or with the combination of DFO and EPO did not protect against gray or white matter damage in the experimental setting applied.

Topics: Animals; Animals, Newborn; Anti-Inflammatory Agents; Antioxidants; Brain Infarction; Caspase 3; Cerebral Cortex; Cytoprotection; Deferoxamine; Disease Models, Animal; Drug Combinations; Drug Synergism; Erythropoietin; Hypoxia-Ischemia, Brain; Microtubule-Associated Proteins; Myelin Basic Protein; Nerve Degeneration; Nerve Fibers, Myelinated; Neurons; Rats; Rats, Wistar

Intracerebral hemorrhage (ICH) is a devastating clinical syndrome for which no truly efficacious therapy has yet been identified. In preclinical studies, erythropoietin (EPO) and its long-lasting analog, darbepoetin alfa, have been demonstrated to be neuroprotective in several models of neuronal insult. The objectives of this study were to analyze whether the systemic administration of recombinant human EPO (rHuEPO) and its long-lasting derivative darbepoetin alfa expedited functional recovery and brain damage in a rat model of ICH.. Experimental ICH was induced in rats by injecting autologous blood into the right striatum under stereotactic guidance. Subsequently, animals underwent placebo treatment, daily injections of rHuEPO, or weekly injections of darbepoetin alfa. Animals were killed 14 days after injury.. Both rHuEPO and darbepoetin alfa were effective in reducing neurological impairment after injury, as assessed by the neurological tasks performed. rHuEPO- and darbepoetin alfa-treated animals exhibited a restricted brain injury with nearly normal parenchymal architecture. In contrast, the saline-treated group exhibited extensive cerebral cytoarchitectural disruption and edema. The number of surviving NeuN-positive neurons was significantly higher in the rats treated with rHuEPO and darbepoetin alfa compared with those that received saline (P < 0.05).. These results demonstrate that weekly administered darbepoetin alfa confers behavioral and histological neuroprotection after ICH in rats similar to that of daily EPO administration. Administration of EPO and its long-lasting recombinant forms affords significant neuroprotection in an ICH model and may hold promise for future clinical applications.

Topics: Animals; Basal Ganglia Hemorrhage; Blood Transfusion, Autologous; Brain; Brain Edema; Brain Infarction; Cerebral Hemorrhage; Corpus Striatum; Darbepoetin alfa; Disease Models, Animal; Drug Administration Schedule; Erythropoietin; Hematinics; Humans; Male; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Treatment Outcome

Carbamylated erythropoietin (CEPO) is a novel neuroprotective agent that does not bind to the classical erythropoietin receptor or affect hematocrit. Since CEPO has not been systematically studied in a fully blinded and randomized manner in an embolic stroke model, we determined if CEPO would be useful to attenuate clinical deficits associated with multiple infarct ischemia using the rabbit small clot embolic stroke model (RSCEM). Rabbits were embolized and treated with vehicle or CEPO within 6 h of embolization and behavioral analysis was conducted 48 h after embolization. Using quantal analysis, we determined the quantity of blood clot (mg) in brain that produce neurologic dysfunction in 50% of the rabbits (P(50)), with intervention considered beneficial if it increased the P(50) compared to controls. CEPO administered between 5 min and 3 h after embolization significantly (p<0.05) improved behavioral function and increased the P(50) value by 55-216%. However, CEPO administration did not improve behavior when administered 6 h following embolization. In conclusion, in the RSCEM, CEPO had a therapeutic window of at least 3 h, where it effectively improved clinical rating scores and motor function. Our results suggest that CEPO may be useful to treat acute ischemic stroke and supports the study of CEPO in stroke patients.

Topics: Animals; Behavior, Animal; Brain Infarction; Brain Ischemia; Erythropoietin; Intracranial Embolism; Male; Neuroprotective Agents; Rabbits; Recovery of Function; Time

Hypoxia-ischemia (HI) is a common injury arising from prematurity/complications at birth and is associated with later language, auditory, and learning impairments.. To investigate the efficacy of two doses (300 or 1000 U/kg) of Erythropoietin (Epo) in protecting against neuropathological and behavioral impairments associated with HI injury in rats.. HI injury (right carotid artery cauterization and 120 min of 8% O(2)) was induced on postnatal day 7 (P7) and Epo or saline was administered i.p. immediately following the procedure. Auditory processing and learning/memory were assessed throughout development.. Both doses of Epo provided behavioral protection following HI injury. Rats given 300 or 1000 U/kg of Epo performed significantly better than HI animals on a short duration complex auditory processing procedure, on a spatial Morris water maze assessing spatial learning/reference memory, and a non-spatial water maze assessing associative learning/reference memory.. Given Epo's extant clinical use (FDA approved for pediatric patients with anemia secondary to prematurity), the current results add to a growing body of literature supporting the use of Epo as a potential protective agent for neurological and behavioral impairments following early HI injury in infants.

Topics: Animals; Animals, Newborn; Atmosphere Exposure Chambers; Auditory Perception; Brain; Brain Infarction; Disease Models, Animal; Dose-Response Relationship, Drug; Erythropoietin; Hearing Loss, Central; Hypoxia-Ischemia, Brain; Learning Disabilities; Male; Maze Learning; Memory Disorders; Neuroprotective Agents; Rats; Rats, Wistar

Blood-brain barrier (BBB) leakage plays a role in the pathogenesis of many pathological states of the brain including ischemia and some neurodegenerative disorders. In recent years, erythropoietin (EPO) has been shown to exert neuroprotection in many pathological conditions including ischemia in the brain. This study aimed to investigate the effects of EPO on BBB integrity, infarct size and lipid peroxidation following global brain ischemia/reperfusion in rats. Wistar male rats were divided into four groups (each group n=8); Group I; control group (sham-operated), Group II; ischemia/reperfusion group, Group III; EPO treated group (24 h before decapitation--000 U/kg r-Hu EPO i.p.), Group IV; EPO+ ischemia/reperfusion group (24 h before ischemia/reperfusion--3000 U/kg r-Hu EPO i.p.). Global brain ischemia was produced by the combination of bilateral common carotid arteries occlusion and hemorrhagic hypotension. Macroscopical and spectrophotometrical measurement of Evans Blue (EB) leakage was observed for BBB integrity. Infarct size was calculated based on 2,3,5-triphenyltetrazolium chloride (TTC) staining. Lipid peroxidation in the brain tissue was determined as the concentration of thiobarbituric acid-reactive substances (TBARS) for each group. Ischemic insult caused bilateral and regional BBB breakdown (hippocampus, cortex, corpus striatum, midbrain, brain stem and thalamus). EPO pretreatment reduced BBB disruption, infarct size and lipid peroxide levels in brain tissue with 20 min ischemia and 20 min reperfusion. These results suggest that EPO plays an important role in protecting against brain ischemia/reperfusion through inhibiting lipid peroxidation and decreasing BBB disruption.

Topics: Animals; Blood-Brain Barrier; Brain Infarction; Brain Ischemia; Carotid Arteries; Carotid Stenosis; Disease Models, Animal; Drug Administration Schedule; Epoetin Alfa; Erythropoietin; Evans Blue; Lipid Peroxidation; Male; Neuroprotective Agents; Rats; Rats, Wistar; Recombinant Proteins; Reperfusion Injury; Thiobarbituric Acid Reactive Substances

Metallothioneins (MTs) are small cysteine-rich proteins found widely throughout the mammalian body, including the CNS. MT-1 and -2 protect against reactive oxygen species and free radicals. We investigated the role of MT-1 and -2 using MT-1,-2 knockout (KO) mice. MT-1,-2 KO mice exhibited greater neuronal damage after permanent middle cerebral artery occlusion (MCAO) than wild-type mice. MT-2 mRNA was significantly increased at 6, 12, and 24 h after MCAO in the wild-type mouse brain [as detected by real-time reverse-transcription polymerase chain reaction (RT-PCR)], while MT-1 and MT-3 were decreased at 12 and 24 h. In an immunohistochemical study, MT expression displayed colocalization with glial fibrillary acidic protein (GFAP)-positive cells (astrocytes) in the penumbra area in wild-type mice. Since erythropoietin (EPO) has been reported to induce MT-1 and -2 gene expression in vitro, we examined its effect after permanent MCAO, and explored the possible underlying mechanism by examining MT-1 and -2 induction in vivo. In wild-type mice, EPO significantly reduced both infarct area and volume at 24 h after the ischemic insult. However, in MT-1,-2 KO mice EPO-treatment did not alter infarct volume (vs. vehicle-treatment). In wild-type mice at 6 h after EPO administration, real-time RT-PCR revealed increased MT-1 and -2 mRNA expression in the cerebral cortex (without MCAO). Further, MT-1 and -2 immunoreactivity was increased in the cortex of EPO-treated mice. These findings indicate that MTs are induced, and may be neuroprotective against neuronal damage, after MCAO. Furthermore, EPO is neuroprotective in vivo during permanent MCAO, and this may be at least partly mediated by MTs.

Topics: Animals; Astrocytes; Brain; Brain Infarction; Brain Ischemia; Cytoprotection; Erythropoietin; Gene Expression Regulation; Glial Fibrillary Acidic Protein; Infarction, Middle Cerebral Artery; Male; Metallothionein; Metallothionein 3; Mice; Mice, Inbred C57BL; Mice, Knockout; Nerve Degeneration; Neuroprotective Agents; RNA, Messenger; Up-Regulation

A large body of evidence indicates that the hormone erythropoietin (EPO) exerts beneficial effects in the central nervous system (CNS). To date, EPO's effect has been assessed in several experimental models of brain and spinal cord injury. This study was conducted to validate whether treatment with recombinant human EPO (rHuEPO) would limit the extent of injury following experimental TBI. Experimental TBI was induced in rats by a cryogenic injury model. rHuEPO or placebo was injected intraperitoneally immediately after the injury and then every 8 h until 2 or 14 days. Forty-eight hours after injury brain water content, an indicator of brain edema, was measured with the wet-dry method and blood-brain barrier (BBB) breakdown was evaluated by assay of Evans blue extravasation. Furthermore, extent of cerebral damage was assessed. Administration of rHuEPO markedly improved recovery from motor dysfunction compared with placebo group (P<0.05). Brain edema was significantly reduced in the cortex of the EPO-treated group relative to that in the placebo-treated group (80.6+/-0.3% versus 91.8%+/-0.8% respectively, P<0.05). BBB breakdown was significantly lower in EPO-treated group than in the placebo-treated group (66.2+/-18.7 mug/g versus 181.3+/-21 mug/g, respectively, P<0.05). EPO treatment reduced injury volume significantly compared with placebo group (17.4+/-5.4 mm3 versus 37.1+/-5.3 mm3, P<0.05). EPO, administered in its recombinant form, affords significant neuroprotection in experimental TBI model and may hold promise for future clinical applications.

Topics: Analysis of Variance; Animals; Blood-Brain Barrier; Brain Edema; Brain Infarction; Brain Injuries; Disease Models, Animal; Erythropoietin; Evans Blue; Functional Laterality; Humans; Male; Neurologic Examination; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Reaction Time; Recombinant Proteins; Time Factors

Both mild hypoxia and exogenous erythropoietin may protect the brain against subsequent severe hypoxia, and the conditioning effect of transient hypoxia is partly mediated by hypoxia-induced endogenous erythropoietin. We now observed in several experimental models that combining transient hypoxia and exogenous erythropoietin may cause neuronal damage. High-dose erythropoietin (40 IU/ml) profoundly impeded synaptic transmission of rat hippocampal slice cultures when used in conjunction with moderate hypoxia (10% O2 for two 8-h periods). Addition of erythropoietin increased viability of cultured rat embryonic cortical neurons at 21% O2 but decreased viability under hypoxic conditions (2% O2) in a dose-dependent fashion. Death of human neuronal precursor cells challenged by oxygen and glucose deprivation was increased by erythropoietin when cells were cultured under hypoxic but not under normoxic conditions. In neonatal rats exposed to moderate hypoxia plus erythropoietin, numbers of degenerating cerebral neurons were increased, as compared to controls or rats subjected to either hypoxia or erythropoietin alone. Thus, erythropoietin may aggravate rather than ameliorate neuronal damage when administered during transient hypoxia.

Topics: Age Factors; Animals; Animals, Newborn; Brain Infarction; Cell Line; Cell Survival; Cells, Cultured; Dose-Response Relationship, Drug; Entorhinal Cortex; Erythropoietin; Glucose; Hippocampus; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Nerve Degeneration; Neurons; Neurotoxins; Organ Culture Techniques; Rats; Rats, Wistar; Reperfusion Injury; Stem Cells; Synaptic Transmission

Recently, erythropoietin (EPO) and the nonerythropoietic derivative asialoEPO have been linked to tissue protection in the nervous system. In this study, we tested their effects in a model of neonatal hypoxia-ischemia (HI) in 7-day-old rats (unilateral carotid ligation and exposure to 7.7% O(2) for 50 min). EPO (10 U/g body weight = 80 ng/g; n = 24), asialoEPO (80 ng/g; n = 23) or vehicle (phosphate-buffered saline with 0.1% human serum albumin; n = 24) was injected intraperitoneally 4 h before HI. Both drugs were protective, as judged by measuring the infarct volumes, neuropathological score and gross morphological score. The infarct volumes were significantly reduced by both EPO (52%) and asialoEPO (55%) treatment, even though the plasma levels of asialoEPO had dropped below the detection limit (1 pm) at the onset of HI, while those of EPO were in the nanomolar range. Thus, a brief trigger by asialoEPO before the insult appears to be sufficient for protection. Proteomics analysis after asialoEPO treatment alone (no HI) revealed at least one differentially up-regulated protein, synaptosome-associated protein of 25 kDa (SNAP-25). Activation (phosphorylation) of ERK was significantly reduced in asialoEPO-treated animals after HI. EPO and the nonerythropoietic asialoEPO both provided significant and equal neuroprotection when administered 4 h prior to HI in 7-day-old rats. The protection might be related to reduced ERK activation and up-regulation of SNAP-25.

Topics: Animals; Animals, Newborn; Asialoglycoproteins; Brain Infarction; Disease Models, Animal; Erythropoietin; Female; Hypoxia-Ischemia, Brain; Male; Membrane Proteins; Nerve Tissue Proteins; Proteomics; Rats; Rats, Wistar; Signal Transduction; Synaptosomal-Associated Protein 25; Treatment Outcome