losartan-potassium and Stroke

Prevention of epilepsy is a great unmet need. Acute central nervous system (CNS) insults such as traumatic brain injury (TBI), cerebrovascular accidents (CVA), and CNS infections account for 15%-20% of all epilepsy. Following TBI and CVA, there is a latency of days to years before epilepsy develops. This allows treatment to prevent or modify postinjury epilepsy. No such treatment exists. In animal models of acquired epilepsy, a number of medications in clinical use for diverse indications have been shown to have antiepileptogenic or disease-modifying effects, including medications with excellent side effect profiles. These include atorvastatin, ceftriaxone, losartan, isoflurane, N-acetylcysteine, and the antiseizure medications levetiracetam, brivaracetam, topiramate, gabapentin, pregabalin, vigabatrin, and eslicarbazepine acetate. In addition, there are preclinical antiepileptogenic data for anakinra, rapamycin, fingolimod, and erythropoietin, although these medications have potential for more serious side effects. However, except for vigabatrin, there have been almost no translation studies to prevent or modify epilepsy using these potentially "repurposable" medications. We may be missing an opportunity to develop preventive treatment for epilepsy by not evaluating these medications clinically. One reason for the lack of translation studies is that the preclinical data for most of these medications are disparate in terms of types of injury, models within different injury type, dosing, injury-treatment initiation latencies, treatment duration, and epilepsy outcome evaluation mode and duration. This makes it difficult to compare the relative strength of antiepileptogenic evidence across the molecules, and difficult to determine which drug(s) would be the best to evaluate clinically. Furthermore, most preclinical antiepileptogenic studies lack information needed for translation, such as dose-blood level relationship, brain target engagement, and dose-response, and many use treatment parameters that cannot be applied clinically, for example, treatment initiation before or at the time of injury and dosing higher than tolerated human equivalent dosing. Here, we review animal and human antiepileptogenic evidence for these medications. We highlight the gaps in our knowledge for each molecule that need to be filled in order to consider clinical translation, and we suggest a platform of preclinical antiepileptogenesis evaluation of potentially repurposable molecu

Topics: Acetylcysteine; Animals; Anticonvulsants; Antioxidants; Atorvastatin; Brain Injuries, Traumatic; Ceftriaxone; Dibenzazepines; Drug Repositioning; Epilepsy; Epilepsy, Post-Traumatic; Erythropoietin; Fingolimod Hydrochloride; GABA Agents; Gabapentin; Humans; Immunologic Factors; Inflammation; Interleukin 1 Receptor Antagonist Protein; Isoflurane; Levetiracetam; Losartan; Neuroprotective Agents; Oxidative Stress; Pregabalin; Pyrrolidinones; Sirolimus; Stroke; Topiramate; Translational Research, Biomedical; Vigabatrin

The loss of blood-brain barrier (BBB) integrity leading to vasogenic edema and brain swelling is a common feature of hypoxic/ischemic brain diseases such as stroke, but is also central to the etiology of other CNS disorders. In the past decades, numerous proteins, belonging to the family of angioneurins, have gained increasing attention as potential therapeutic targets for ischemic stroke, but also other CNS diseases attributed to BBB dysfunction. Angioneurins encompass mediators that affect both neuronal and vascular function. Recently, increasing evidence has been accumulated that certain angioneurins critically determine disease progression and outcome in stroke among others through multifaceted effects on the compromised BBB. Here, we will give a concise overview about the family of angioneurins. We further describe the most important cellular and molecular components that contribute to structural integrity and low permeability of the BBB under steady-state conditions. We then discuss BBB alterations in ischemic stroke, and highlight underlying cellular and molecular mechanisms. For the most prominent angioneurin family members including vascular endothelial growth factors, angiopoietins, platelet-derived growth factors and erythropoietin, we will summarize current scientific literature from experimental studies in animal models, and if available from clinical trials, on the following points: (i) spatiotemporal expression of these factors in the healthy and hypoxic/ischemic CNS, (ii) impact of loss- or gain-of-function during cerebral hypoxia/ischemia for BBB integrity and beyond, and (iii) potential underlying molecular mechanisms. Moreover, we will highlight novel therapeutic strategies based on the activation of endogenous angioneurins that might improve BBB dysfuntion during ischemic stroke.

Topics: Angiopoietins; Animals; Blood-Brain Barrier; Brain Ischemia; Erythropoietin; Humans; Stroke; Vascular Endothelial Growth Factor A

Erythropoietin (EPO) for treating acute ischemic stroke (AIS) has been investigated in many studies. However, the evidence was inconsistent. Thus, a systematic review and metaanalysis were performed to elucidate the role of EPO in treating patients with AIS.. Two electronic databases (PubMed and EMBASE) were used. 30-day NIHSS measures primary outcome while all-cause mortality in the follow up and 90-day Barthel Index were regarded as secondary outcome. Results are presented as relative risk (RR), standardized mean difference (SMD) and 95% confidence intervals (CI). We employed Stata software to perform the meta-analysis.. Four randomized controlled trials (RCTs) involving 784 patients were contained in this metaanalysis. The total combined results on 30-day NIHSS were (SMD = -0.52, 95% CI: -1.39, 0.34) with random-effects model and sensitivity analysis showed a significant difference after excluding the Ehrenreich 2009 trial. The total combined secondary measured results were (RR=1.72, 95% CI: 1.10, 2.70) and (SMD = 0.01, 95% CI: -0.14, 0.16) for all-cause mortality and 90-day Barthel Index. In the subgroup analysis by using recombinant tissue plasminogen activator (rtPA) earlier, the rtPA group showed increased all-cause mortality with the result of (RR = 1.92, 95% CI: 1.04, 3.52), but not in non-rtPA group.. To our systematic review and meta-analysis, we didn't recommend EPO administration for patients with AIS, especially with the combination of rtPA. Large RCTs are warranted to examine EPO efficacy in AIS patients in the future.

Topics: Animals; Brain Ischemia; Erythropoietin; Humans; Randomized Controlled Trials as Topic; Recombinant Proteins; Stroke; Tissue Plasminogen Activator

Over recent decades, experimental and clinical stroke studies have identified a number of neurorestorative treatments that stimulate neural plasticity and promote functional recovery. In contrast to the acute stroke treatments thrombolysis and endovascular thrombectomy, neurorestorative treatments are still effective when initiated days after stroke onset, which makes them applicable to virtually all stroke patients. In this article, selected physical, pharmacological and cell-based neurorestorative therapies are discussed, with special emphasis on interventions that have already been transferred from the laboratory to the clinical setting. We explain molecular and structural processes that promote neural plasticity, discuss potential limitations of neurorestorative treatments, and offer a speculative viewpoint on how neurorestorative treatments will evolve.

Topics: Axons; Brain; Brain Ischemia; Cytidine Diphosphate Choline; Erythropoietin; Granulocyte Colony-Stimulating Factor; Humans; Myelin Proteins; Neovascularization, Physiologic; Neurogenesis; Neurological Rehabilitation; Neuronal Plasticity; Nogo Proteins; Nootropic Agents; Phosphodiesterase 5 Inhibitors; Recovery of Function; Regeneration; Selective Serotonin Reuptake Inhibitors; Stem Cell Transplantation; Stroke; Stroke Rehabilitation

Subarachnoid haemorrhage (SAH) caused by a ruptured aneurysm accounts for only 5 % of strokes, but occurs at a fairly young age and carries a poor prognosis. Delayed cerebral ischaemia (DCI) is an important cause of death and dependence after aneurysmal SAH. The current mainstay of preventing DCI is nimodipine and maintenance of normovolemia, but even with this strategy DCI occurs in a considerable proportion of patients.Several drugs have been developed that have the potential to limit cerebral vasospasm and delayed ischaemic neurologic deficit, thus improving outcome for patients. However, although numerous agents can prevent arterial narrowing and/or block the excitatory cascade of events leading to ischaemic neuronal death in experimental conditions, there is still no pharmacologic agent that has been shown conclusively to improve the outcome in clinical practice.Erythropoietin (EPO) is a well-known erythropoietic hormone recently found to exert neuroprotective properties and has been shown to reduce cerebral vasospasm and infarct volume after experimental SAH. In humans, although EPO treatment did not impact the overall incidence of vasospasm, it significantly reduced the incidence of severe vasospasm, the incidence of delayed ischaemic deficits with new cerebral infarcts, and the duration of impaired autoregulation. The current study provides new evidence for the potential benefit and relative safety of EPO for the treatment of SAH in humans. Future clinical trials will hopefully provide definite evidence whether EPO treatment is beneficial in SAH patients.

Topics: Animals; Brain Ischemia; Erythropoietin; Humans; Stroke; Subarachnoid Hemorrhage; Vasospasm, Intracranial

Recombinant human erythropoietin (rhEPO), over the past decade, was hailed as an auspicious therapeutic strategy for various types of brain injuries. The promising results from experiments conducted in animal models of stroke led to a hurried clinical trial that was swiftly aborted in Phase II. The multiple neuroprotective modalities of rhEPO failed to translate smoothly to human adult ischemic brain injury and provided limited aid to neonates. In light of the antithetical results, several questions were raised as to why and how this clinical trial failed. There was bolstering evidence from the preliminary studies that pointed to a bright future. Therefore, the objective of this review is to address these questions by discussing the signaling pathways of rhEPO that are reported to mediate the neuroprotective effect in various animal models of brain injury. Major biomedical bibliographical databases (MEDLINE, ISI, PubMed, and Cochrane Library) were searched with the use of keywords such as erythropoietin, stroke, neonatal hypoxia ischemia, intracerebral hemorrhage, etc. This article will discuss the confounding factors that influence the efficacy of rhEPO treatment hence challenging its clinical translatability. Lastly, rhEPO may still be a promising therapeutic candidate for neonates in spite of its shortcoming in clinical trial if caution is taken with the dose and duration of its administration.

Topics: Erythropoietin; Humans; Recombinant Proteins; Signal Transduction; Stroke

Colony stimulating factors (CSFs), also called haematopoietic growth factors, regulate bone marrow production of circulating red and white cells, and platelets. Some CSFs also mobilise the release of bone marrow stem cells into the circulation. CSFs have been shown to be neuroprotective in experimental stroke.. To assess (1) the safety and efficacy of CSFs in people with acute or subacute ischaemic or haemorrhagic stroke, and (2) the effect of CSFs on circulating stem and blood cell counts.. We searched the Cochrane Stroke Group Trials Register (last searched September 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 4), MEDLINE (1985 to September 2012), EMBASE (1985 to September 2012) and Science Citation Index (1985 to September 2012). In an attempt to identify further published, unpublished and ongoing trials we contacted manufacturers and principal investigators of trials (last contacted April 2012). We also searched reference lists of relevant articles and reviews.. We included randomised controlled trials recruiting people with acute or subacute ischaemic or haemorrhagic stroke. CSFs included stem cell factor (SCF), erythropoietin (EPO), granulocyte colony stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF), macrophage-colony stimulating factor (M-CSF, CSF-1), thrombopoietin (TPO), or analogues of these. The primary outcome was functional outcome at the end of the trial. Secondary outcomes included safety at the end of treatment, death at the end of follow-up, infarct volume and haematology measures.. Two review authors (TE and NS) independently extracted data and assessed trial quality. We contacted study authors for additional information.. We included a total of 11 studies involving 1275 participants. In three trials (n = 782), EPO therapy was associated with a significant increase in death by the end of the trial (odds ratio (OR) 1.98, 95% confidence interval (CI) 1.19 to 3.3, P = 0.009) and a non-significant increase in serious adverse events. EPO significantly increased the red cell count with no effect on platelet or white cell count, or infarct volume. Two small trials of carbamylated EPO have been completed but have yet to be reported. We included eight small trials (n = 548) of G-CSF. G-CSF was associated with a non-significant reduction in early impairment (mean difference (MD) -0.4, 95% CI -1.82 to 1.01, P = 0.58) but had no effect on functional outcome at the end of the trial. G-CSF significantly elevated the white cell count and the CD34+ cell count, but had no effect on infarct volume. Further trials of G-CSF are ongoing.. There are significant safety concerns regarding EPO therapy for stroke. It is too early to know whether other CSFs improve functional outcome.

Topics: Colony-Stimulating Factors; Erythropoietin; Granulocyte Colony-Stimulating Factor; Humans; Randomized Controlled Trials as Topic; Stroke

Topics: Acute Lung Injury; Adult; Anemia; Blood Preservation; Blood Specimen Collection; Brain Injuries; Critical Illness; Erythrocyte Transfusion; Erythropoietin; Hemorrhage; Humans; Myocardial Ischemia; Nervous System Diseases; Sepsis; Shock; Stroke; Subarachnoid Hemorrhage

The most common cause of stroke is cerebral ischemia, where blood flow to the brain is interrupted due to a thrombus in a major cerebral artery. Currently, the only therapeutic approach available is thrombolysis. A more recent approach that has started to gain attention is neuroprotection, the ability to prevent neuronal death and enhance endogenous protective mechanisms. Several studies have shown the neuroprotective action of Erythropoietin (EPO). A potential problem in the use of EPO for neurodegenerative disorders is the undesirable erythropoietic side effects. In this context, investigations have been focused to develop derivatives of EPO lacking erythropoietic activity but retaining neuroprotective potential. Low sialic acid-containing EPO (Neuro EPO) is very similar to the one that occurs in the mammalian brain and is rapidly degraded by the liver. Similar neuroprotective effects had been observed with neuro EPO, original recombinant human EPO and EPO variants in ischemia models. Intranasal route could be safe and hematological side effects could be avoided. Neuro EPO that constitutes a new agent has retained the neuroprotective effects without stimulating the EPOR in the bone marrow and can therefore be used without increasing the hematocrit. This review gives a brief introduction to the no hematopoietic effects of EPO, the evidence of neuroprotective effect, the alternatives for obtaining an EPO derivate without hematological side effects and discusses the advantages of nasal administration of Neuro EPO for neuroprotective stroke treatment.

Topics: Administration, Intranasal; Animals; Erythropoietin; Humans; Neuroprotective Agents; Reproducibility of Results; Stroke; Treatment Outcome

Tissue plasminogen activator (tPA) administered within 4.5h of symptom onset restores cerebral blood flow (CBF) and promotes neurological recovery of stroke patients. However, the narrow therapeutic time window and the risk of intracerebral hemorrhage after tPA treatment pose major hurdles to its clinical usage. In light of the failures of neuroprotective therapies in clinical trials, emerging concepts suggest that neuroprotection alone without restoration of tissue perfusion and vascular integrity may not be adequate for treatment of acute stroke. Here we review evidence of the use of adjuvant pharmacological agents to extend the therapeutic window for tPA via targeting the neurovascular unit and the underlying mechanisms of the combination therapy in experimental stroke.

Topics: Anti-Bacterial Agents; Antineoplastic Agents; Boronic Acids; Bortezomib; Cerebral Hemorrhage; Drug Therapy, Combination; Erythropoietin; Fibrinolytic Agents; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Minocycline; Pyrazines; Stroke; Tissue Plasminogen Activator

Erythropoietin (EPO) has shown promise as a neuroprotectant in animal models of ischemic stroke. EPO is thought not only to protect neurons from cell death, but also to promote regeneration after stroke. Here, we report a systematic review and meta-analysis of the efficacy of EPO in animal models of focal cerebral ischemia. Primary outcomes were infarct size and neurobehavioral outcome. Nineteen studies involving 346 animals for infarct size and 425 animals for neurobehavioral outcome met our inclusion criteria. Erythropoietin improved infarct size by 30.0% (95% CI: 21.3 to 38.8) and neurobehavioral outcome by 39.8% (33.7 to 45.9). Studies that randomized to treatment group or that blinded assessment of outcome showed lower efficacy. Erythropoietin was tested in animals with hypertension in no studies reporting infarct size and in 7.5% of the animals reporting neurobehavioral outcome. These findings show efficacy for EPO in experimental stroke, but when the impact of common sources of bias are considered, this efficacy falls, suggesting we may be overestimating its potential benefit. As common human co-morbidities may reduce therapeutic efficacy, broader testing to delineate the range of circumstances in which EPO works best would be beneficial.

Topics: Animals; Behavior, Animal; Brain Ischemia; Databases, Factual; Disease Models, Animal; Erythropoietin; Humans; Hypertension; Neuroprotective Agents; Stroke

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

Recombinant erythropoietin (rEPO) failed in a recent clinical study to protect from damages induced by ischemic stroke. The lack of acute treatments in ischemic stroke and the promising outcome in numerous preclinical studies in vivo demands a more critical evaluation of the future use of EPO as an acute treatment.. The current use and administration of rhEPO and its analogs in animal models and the future use of this cytokine in the treatment of ischemic stroke.. In this review the potential reasons for the failure of EPO in the clinical trial are analysed and whether the preclinical trials sufficiently evaluated the true potential of recombinant EPO and its analogs is assessed. Alternative methods for administration of EPO to enhance its potential as a neuroprotective drug in ischemic stroke are discussed.. Failure in clinical trial does not necessarily indicate the lack of therapeutic potential of EPO. This review encourages further investigation of the true potential of EPO as a candidate drug for the treatment of ischemic stroke by improved preclinical experimental design and utilization of alternative administration methods.

Topics: Administration, Intranasal; Animals; Brain Ischemia; Drug Delivery Systems; Erythropoietin; Humans; Injections, Intraventricular; Nanoparticles; Neuroprotective Agents; Recombinant Proteins; Stroke

Following stroke or traumatic damage, neuronal death via both necrosis and apoptosis causes loss of functions, including memory, sensory perception, and motor skills. As necrosis has the nature to expand, while apoptosis stops the cell death cascade in the brain, necrosis is considered to be a promising target for rapid treatment for stroke. We identified the nuclear protein, prothymosin alpha (ProTalpha) from the conditioned medium of serum-free culture of cortical neurons as a key protein-inhibiting necrosis. In the culture of cortical neurons in the serum-free condition without any supplements, ProTalpha inhibited the necrosis, but caused apoptosis. In the ischemic brain or retina, ProTalpha showed a potent inhibition of both necrosis and apoptosis. By use of anti-brain-derived neurotrophic factor or anti-erythropoietin IgG, we found that ProTalpha inhibits necrosis, but causes apoptosis, which is in turn inhibited by ProTalpha-induced neurotrophins under the condition of ischemia. From the experiment using anti-ProTalpha IgG or antisense oligonucleotide for ProTalpha, it was revealed that ProTalpha has a pathophysiological role in protecting neurons in stroke.

Topics: Apoptosis; Brain; Brain-Derived Neurotrophic Factor; Cell Death; Cerebral Cortex; Culture Media, Conditioned; Erythropoietin; Immunoproteins; Ischemia; Necrosis; Nerve Growth Factors; Neurons; Protein Precursors; Retina; Stroke; Thymosin

Since the realization that erythropoietin (EPO) molecules have 'neuroprotective' properties, they have been investigated as treatments for acute ischemic stroke (AIS), but not systematically. The results of the 2009 clinical trial showed that EPO was ineffective as a stroke treatment, and moreover, increased mortality when combined with tissue plasminogen activator. Currently, CEPO, an EPO analog, is entering into a safety, tolerability and pharmacokinetic clinical trial for the treatment of AIS.. This review covers translational and clinical studies carried out over the period 1998 - 2010.. The primary aim of this article is to review the information available regarding the pharmacological and biological characteristics of EPO molecules. Second, based upon the translational research with EPO molecules in preclinical stroke models, a recommendation is made regarding the continued development of EPO molecules as an option to treat AIS.. EPO, CEPO and helix B peptide EPO analogs have significant neuroprotective activity is preclinical stroke models. However, given the detrimental effect of EPO in a recent clinical trial, preclinical safety studies of EPO molecules in embolic stroke models that parallel acute ischemic stroke in humans are warrented.

Topics: Adult; Aged; Aged, 80 and over; Brain Ischemia; Clinical Trials as Topic; Drug Evaluation, Preclinical; Erythropoietin; Female; Humans; Male; Middle Aged; Signal Transduction; Stroke; Translational Research, Biomedical; Young Adult

Subarachnoid hemorrhage (SAH) has a worldwide incidence of approximately 10.5 cases per 100,000 person-years and constitutes 3% of all strokes. Erythropoietin (EPO) has recently been proposed for the treatment of a variety of brain diseases, including SAH, because of its neuroprotective effects. Hence, the current evidence in the published literature was reviewed to determine the potential utility of EPO in the treatment of SAH.. A careful retrospective review of the literature was performed to determine the potential benefit of employing EPO in the treatment of SAH and its sequelae.. Careful literature review revelaed that the use of EPO may not necessarily reduce the incidence of vasospasm after SAH, but it may reduce the severity and its eventual outcome.. Given the recent trial results, a dose-escalation study and subsequent randomized trial should be considered.

Topics: Erythropoietin; Humans; Neuroprotective Agents; Recombinant Proteins; Retrospective Studies; Stroke; Subarachnoid Hemorrhage; Treatment Outcome; Vasospasm, Intracranial

Ischemic stroke causes brain damage by multiple pathways. Previous stroke trials have demonstrated that drugs targeting one or only a few of these pathways fail to improve clinical outcome after stroke. Drugs with multimodal actions have been suggested to overcome this challenge. In this review, we describe the mechanisms of action of agents approved for secondary prevention of ischemic stroke, such as antiplatelet, antihypertensive, and lipid-lowering drugs. These drugs exhibit considerable properties beyond their classical mechanisms, including neuroprotective and neuroregenerative properties. In addition, candidate stroke drugs currently studied in clinical phase III trials are described. Among these, albumin, hematopoietic growth factors, and citicoline have been identified as promising agents with multiple mechanisms. These drugs offer hope that additional treatment options for the acute phase after a stroke will become available in the near future.

Topics: Albumins; Animals; Antihypertensive Agents; Aspirin; Brain Ischemia; Clopidogrel; Cytidine Diphosphate Choline; Dipyridamole; Erythropoietin; Granulocyte Colony-Stimulating Factor; Humans; Hypolipidemic Agents; Neuroprotective Agents; Platelet Aggregation Inhibitors; Stroke; Ticlopidine

The growth factor erythropoietin (EPO) and erythropoietin receptors (EPOR) are expressed in the nervous system. Neuronal expression of EPO and EPOR peaks during brain development and is upregulated in the adult brain after injury. Peripherally administered EPO, and at least some of its variants, cross the blood-brain barrier, stimulate neurogenesis, neuronal differentiation, and activate brain neurotrophic, anti-apoptotic, anti-oxidant and anti-inflammatory signaling. These mechanisms underlie their tissue protective effects in nervous system disorders. As the tissue protective functions of EPO can be separated from its stimulatory action on hematopoiesis, novel EPO derivatives and mimetics, such as asialo-EPO and carbamoylated EPO have been developed. While the therapeutic potential of the novel EPO derivatives continues to be characterized in preclinical studies, the experimental findings in support for the use of recombinant human (rh)EPO in human brain disease have already been translated to clinical studies in acute ischemic stroke, chronic schizophrenia, and chronic progressive multiple sclerosis. In this review article, we assess the studies on EPO and, in particular, on its structural or functional variants in experimental models of nervous system disorders, and we provide a short overview of the completed and ongoing clinical studies testing EPO as neuroprotective/neuroregenerative treatment option in neuropsychiatric disease.

Topics: Animals; Brain Diseases; Erythropoietin; Humans; Nervous System; Neurodegenerative Diseases; Neurons; Neuroprotective Agents; Peripheral Nerves; Receptors, Erythropoietin; Retinal Diseases; Schizophrenia; Signal Transduction; Spinal Cord Injuries; Stroke

Erythropoietin (EPO) was explored regarding its suitability as a candidate stroke drug in animal experimental studies. We performed a meta-analysis to obtain an overall impression of the efficacy of EPO in published animal experimental stroke studies and for potential guidance of future clinical studies.. By electronic and manual searches of the literature, we identified studies describing the efficacy of EPO in experimental focal cerebral ischemia. Data on study quality, EPO dose, time of administration, and outcome measured as infarct volume or functional deficit were extracted. Data from all studies were pooled by means of a meta-analysis.. Sixteen studies were included in the meta-analysis. When administered after the onset of ischemia, EPO and its analogues reduced infarct size by 32% and improved neurobehavioral deficits significantly. A meta-regression suggests higher doses of EPO to be associated with smaller infarct volumes. When administered earlier than 6 hours EPO was more effective compared to a later treatment initiation. Both hematopoietic and nonhematopoietic EPO analogues showed efficacy in experimental stroke.. In conclusion, this analysis further strengthens confidence in the efficacy of EPO and its analogues in stroke therapy. Nonhematopoietic EPO analogues which are known to have less systemic adverse effects compared to EPO are also promising candidate stroke drugs. Further experimental studies are required that evaluate the safety of a combination of EPO with thrombolysis and whether EPO is also effective in animals with comorbidity.

Topics: Animals; Brain Ischemia; Disease Models, Animal; Dose-Response Relationship, Drug; Erythropoietin; Gerbillinae; Meta-Analysis as Topic; Mice; Rats; Stroke; Thrombolytic Therapy; Time Factors

Intranasal delivery provides a practical, noninvasive method of bypassing the blood-brain barrier (BBB) in order to deliver therapeutic agents to the brain. This method allows drugs that do not cross the BBB to be delivered to the central nervous system in a few minutes. With this technology, it will be possible to eliminate systemic administration and its potential side effects. Using the intranasal delivery system, researchers have demonstrated neuroprotective effects in different animal models of stroke using erythropoietin (EPO) as a neuroprotector or other different types of EPO without erythropoiesis-stimulating activity. These new molecules retain their ability to protect neural tissue against injury and they include Asialoerythropoietin (asialoEPO) carbamylated EPO (CEPO), and rHu-EPO with low sialic acid content (Neuro-EPO). Contrary to the other EPO variants, Neuro-EPO is not chemically modified, making it biologically similar to endogenous EPO, with the advantage of less adverse reactions when this molecule is applied chronically. This constitutes a potential benefit of Neuro-EPO over other variants of EPO for the chronic treatment of neurodegenerative illnesses. Nasal administration of EPO is a potential, novel, neurotherapeutic approach. However, it will be necessary to initiate clinical trials in stroke patients using intranasal delivery in order to obtain the clinical evidence of its neuroprotectant capacity in the treatment of patients with acute stroke and other neurodegenerative disorders. This new therapeutic approach could revolutionize the treatment of neurodegenerative disorders in the 21st century.

Topics: Administration, Intranasal; Animals; Asialoglycoproteins; Blood-Brain Barrier; Brain Ischemia; Clinical Trials as Topic; Disease Models, Animal; Erythropoietin; Humans; Neurodegenerative Diseases; Neuroprotective Agents; Receptors, Erythropoietin; Recombinant Proteins; Stroke

Recombinant human erythropoietin was produced soon after the discovery of the erythropoietin gene in 1985 and since then, it is used in various clinical conditions such as chronic renal failure. Moreover, experimental studies have shown that erythropoietin exerts neuroprotective action as well. Recently, a clinical trial yielded promising results concerning the use of erythropoietin in stroke management. In this review, we summarize the main data which suggest that recombinant human erythropoietin and its analogues may indeed have a role in stroke treatment.

Topics: Acute Disease; Animals; Brain; Brain Ischemia; Clinical Trials as Topic; Erythropoietin; Humans; Neuroprotective Agents; Recombinant Proteins; Stroke; Treatment Outcome

Carbamylated erythropoietin (CEPO) is a modified erythropoietin molecule not affecting hematocrit. It is a potentially important pharmacological agent that may be applied to the treatment of several diseases affecting central and peripheral system neurons.. Carbamylated erythropoietin is a prime candidate for development because of its potent cell survival and function enhancing effects. This article reviews the preclinical development profile of CEPO in animal models to determine whether further clinical development is justified.. The review spans a detailed analysis of patents and scientific publications related to CEPO in animal models.. Use of CEPO in treating diseases such as stroke and traumatic brain and spinal cord injuries is important because these conditions affect millions of patients every year. Extensive preclinical studies support further clinical studies of CEPO for acute ischemic stroke. However, further studies are required for testing CEPO in patients with many other indications.

Topics: Animals; Brain Injuries; Clinical Trials as Topic; Diabetic Neuropathies; Disease Models, Animal; Erythropoietin; Humans; Motor Neuron Disease; Nervous System Diseases; Spinal Cord Injuries; Stroke; Treatment Outcome

Neonatal stroke is increasingly recognized in preterm and term infants, and the rate of arterial ischemic infarction occurring around the time of birth is as high as the annual incidence of large-vessel ischemic stroke in adults. Thus, neonatal stroke is a major contributor to perinatal morbidity and mortality, and a considerable number of these children will develop long-term neurodevelopmental disabilities. Our ability to investigate this situation has been limited by the technical challenges in developing suitable animal models. Our objective is to describe recent evidence in relation to animal models of neonatal stroke. In addition, we review and report potential neuroprotective strategies specific to neonatal stroke, with a focus on erythropoietin and cardiotrophin-1 because of their potential role in protection as well as repair.

Topics: Animals; Animals, Newborn; Cytokines; Disease Models, Animal; Dose-Response Relationship, Drug; Erythropoietin; Humans; Nerve Tissue Proteins; Neuroprotective Agents; Risk Factors; Stroke; Time Factors

Two hematopoietic cytokines are currently gaining increasing attention within neurological research. Erythropoietin (EPO) and granulocyte-colony stimulating factor (G-CSF) have long been known for their ability to induce the proliferation of certain populations of hematopoietic lineage cells. However, it has recently been found that EPO, G-CSF, and their respective receptors are also expressed in the human central nervous system (CNS) and may be an important part of the brain's endogenous system of protection. Both hematopoietic cytokines have been shown to have neuroprotective potential in a variety of animal disease models both in vitro and in vivo, through the inhibition of apoptosis, induction of angiogenesis, exertion of anti-inflammatory and neurotrophic effects, as well as by the enhancement of neurogenesis. EPO and G-CSF have been extensively studied in the context of hematological disorders and have recently been successfully applied in the first clinical trials in stroke patients. Intravenous high-dose EPO therapy was associated with an improvement in the clinical outcome and preclinical studies with intravenous high-dose G-CSF therapy have clearly shown that it has considerable neuroprotective potential in the acute, as well as in the chronic phase of stroke. In this review, the current knowledge of the neuroprotective mechanisms of EPO and G-CSF is summarized with regard to in vitro and in vivo data. Focus is placed on the role of EPO in neurological disease models with an emphasis on its influence on functional outcome. New experimental results are assessed in detail and correlated with the findings of recent clinical studies.

Topics: Animals; Apoptosis; Brain; Erythropoietin; Granulocyte Colony-Stimulating Factor; Humans; In Vitro Techniques; Inflammation; Models, Neurological; Neovascularization, Physiologic; Nervous System Diseases; Neurology; Neuroprotective Agents; Parkinson Disease; Research Design; Signal Transduction; Stroke

Colony stimulating factors (CSFs), also called haematopoietic growth factors, regulate bone marrow production of circulating red and white cells, and platelets. They have been shown to be neuroprotective in experimental stroke. Some CSFs also mobilise the release of bone marrow stem cells into the circulation.. To assess the effects of CSFs on functional outcome and haematology measures in patients with acute or subacute stroke.. We searched the Cochrane Stroke Group Trials Register (last searched November 2006), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 2, 2006), MEDLINE (1985 to June 2006), EMBASE (1985 to June 2006), and Science Citation Index (1985 to June 2006). In an attempt to identify further published, unpublished and ongoing trials we contacted manufacturers and principal investigators of trials (last contacted 2006). We also searched reference lists of relevant articles and reviews.. Unconfounded randomised controlled trials recruiting patients with acute or subacute ischaemic or haemorrhagic stroke were included. CSFs included stem cell factor (SCF), erythropoietin (EPO), granulocyte colony stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF), macrophage-colony stimulating factor (M-CSF, CSF-1), and thrombopoietin (TPO), or analogues of these. The primary outcome was functional outcome (assessed as combined death or disability and dependency using scales such as the modified Rankin Scale or Barthel Index) at the end of the trial. Secondary outcomes included safety at the end of treatment (death, impairment, deterioration, extension or recurrence), death at the end of follow up, and haematology measures (blood counts at or around day seven after treatment commenced).. Two review authors independently extracted data and assessed trial quality. Study authors were contacted for additional information.. No large trials were identified. EPO therapy was associated with a non-significant reduction in neurological impairment in one small trial (n = 40 participants) but had no significant effect on haematological measures. G-CSF was associated with a non-significant reduction in combined death and dependency in two small trials (n = 46 participants) although there was substantial heterogeneity in this result. G-CSF significantly elevated white cell count in three trials (n = 91). Further small trials of EPO and G-CSF are ongoing.. No large trials of EPO, G-CSF or other colony stimulating factors have been performed and it is too early to know whether CSFs improve functional outcome.

Topics: Colony-Stimulating Factors; Erythropoietin; Granulocyte Colony-Stimulating Factor; Humans; Randomized Controlled Trials as Topic; Stroke

Treatments for spontaneous intracerebral, thrombolytic-induced and intraventricular hemorrhages (IVH) are still at the preclinical or early clinical investigational stages. There has been some renewed interest in the use of surgical evacuation surgery or thrombolytics to remove hematomas, but these techniques can be used only for specific types of brain bleeding. The STICH (Surgical Trial in Intracerebral Haemorrhage) clinical trials should provide some insight into the potential for such techniques to counteract hematoma-induced damage and subsequently, morbidity and mortality. More recently, clinical trials (ATACH [Antihypertensive Treatment in Acute Cerebral Hemorrhage] and INTERACT [Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial]) have begun testing whether or not regulating blood pressure affects the well-being of hemorrhage patients, but the findings thus far have not conclusively demonstrated a positive result. More promising trials, such as the early stage CHANT (Cerebral Hemorrhagic And NXY-059 Treatment) and the late stage FAST (Factor VIIa for Acute Hemorrhagic Stroke Treatment), have addressed whether or not manipulating oxidative stress and components of the blood coagulation cascade can achieve an improved prognosis following spontaneous hemorrhages. However, CHANT was halted prematurely because although it showed that the spin trap agent NXY-059 was safe, it also demonstrated that the drug was ineffective in treating acute ischemic stroke. In addition, the recombinant activated factor VII FAST trial recently concluded with only modestly positive results. Despite a beneficial effect on the primary end point of reducing hemorrhage volume, controlling the coagulation cascade with recombinant factor VIIa did not decrease the mortality rate. Consequently, Novo Nordisk has abandoned further development of the drug for the treatment of intracerebral hemorrhaging. Even though progress in hemorrhage therapy that successfully reduces the escalating morbidity and mortality rate associated with brain bleeding is slow, perseverance and applied translational drug development will eventually be productive. The urgent need for such therapy becomes more evident in light of concerns related to uncontrolled high blood pressure in the general population, increased use of blood thinners by the elderly (e.g., warfarin) and thrombolytics by acute ischemic stroke patients, respectively. The future of drug development for hemorrhage may requi

Topics: Animals; Antihypertensive Agents; Antioxidants; Benzenesulfonates; Blood Pressure; Cardiovascular Agents; Coagulants; Disease Models, Animal; Drug Design; Enzyme Inhibitors; Erythropoietin; Excitatory Amino Acid Antagonists; Factor VIIa; Hemostasis; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Intracranial Hemorrhages; Oxidative Stress; Signal Transduction; Stroke; Treatment Outcome

Nervous system diseases are very complex conditions comprising a large variety of local and systemic responses. Several therapeutic agents interfering with all or in part the biochemical steps that ultimately cause neuronal death have been demonstrated to be neuroprotective in preclinical models. However, all the agents so far investigated have inexorably failed in the phase III trials carried out. A large body of evidence suggests that the hormone erythropoietin (EPO), besides its well-known hematopoietic action, exerts beneficial effects in the central nervous system. EPO's effect has been assessed in several experimental models of brain and spinal cord injury thus becoming a serious candidate for neuroprotection. The use of EPO as neuroprotectant raises several questions. Besides dosage and therapeutic time window, the safety of recombinant EPO administration in the setting of nervous system diseases takes priority over all other questions. Although recombinant EPO seems to be potentially safe at the neuroprotective proved doses, cardiovascular or cerebrovascular events can occur as a result of its bone marrow stimulating activities. The successful trial using EPO in patients with ischemic stroke and the large body of experimental evidence encourages intensive evaluation of this cytokine to support safe and larger clinical trials in the near future.

Topics: Animals; Enzyme Activation; Erythropoietin; Humans; Mitogen-Activated Protein Kinases; Models, Biological; Neuroprotective Agents; Recombinant Proteins; Stroke; Treatment Outcome

Colony stimulating factors (CSFs), also called haematopoietic growth factors, regulate bone marrow production of circulating red and white cells, and platelets. They have been shown to be neuroprotective in experimental stroke. Some CSFs also mobilise the release of bone marrow stem cells into the circulation.. We systematically assessed the effects of CSFs on functional outcome and haematology measures in patients with acute or subacute stroke enrolled into randomised controlled trials.. We searched the Cochrane Stroke Group Trials Register (last searched February 2005), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2005), MEDLINE (1985 to March 2006), EMBASE (1985 to November 2005), and Science Citation Index (1985 to November 2005). In an attempt to identify further published, unpublished and ongoing trials we contacted manufacturers and principal investigators of trials (last contacted 2005). We also searched reference lists of relevant articles and reviews.. Unconfounded randomised controlled trials recruiting patients with acute or subacute ischaemic or haemorrhagic stroke were included. CSFs included stem cell factor (SCF), erythropoietin (EPO), granulocyte colony stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF), macrophage-colony stimulating factor (M-CSF, CSF-1), and thrombopoietin (TPO), or analogues of these. The primary outcome was functional outcome (assessed as combined death or disability and dependency using scales such as the modified Rankin Scale or Barthel Index) at the end of the trial. Secondary outcomes included safety at the end of treatment (death, impairment, deterioration, extension or recurrence), death at the end of follow up, and haematology measures (blood counts at or around day seven after treatment commenced).. Data on measures by intention to treat (where available) were collected and analysed as dichotomous or continuous outcomes, as relevant, using random-effects models. Heterogeneity was assessed.. No large trials were identified. EPO therapy was associated with a non-significant reduction in neurological impairment in one small trial (n = 40 participants) but had no significant effect on haematological measures. Further small trials of EPO and G-CSF are ongoing.. No large trials of EPO, G-CSF or other colony stimulating factors have been performed and it is too early to know whether CSFs improve functional outcome.

Topics: Colony-Stimulating Factors; Erythropoietin; Humans; Randomized Controlled Trials as Topic; Stroke

There is a compelling need to develop cell and pharmacological therapeutic approaches to be administered beyond the hyperacute phase of stroke. These therapies capitalize on the capacity of the brain for neuroregeneration and neuroplasticity and are designed to reduce neurological deficits after stroke. This review provides an update of bone marrow-derived mesenchymal stem cells (MSCs) and select pharmacological agents in clinical use for other indications that promote the recovery process in the subacute and chronic phases after stroke. Among these agents are 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins), erythropoietin (EPO), and phosphodiesterase type 5 (PDE-5) inhibitors and nitric oxide (NO) donors. Both the MSCs and the pharmacologic agents potentiate brain plasticity and neurobehavioral recovery after stroke.

Topics: Animals; Cyclic GMP; Erythropoietin; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Mesenchymal Stem Cell Transplantation; Nitric Oxide Donors; Phosphodiesterase Inhibitors; Recombinant Proteins; Stroke; Stroke Rehabilitation; Vascular Endothelial Growth Factor A

Topics: Animals; Apoptosis; Brain Diseases; Brain Ischemia; Cerebral Hemorrhage; Cerebrovascular Disorders; Erythropoietin; Humans; Ischemia; Neurons; Neuroprotective Agents; Stroke

The vascular events that happen during ischemic stroke worsen outcomes in patients by causing edema, hemorrhagic transformation, and general neurologic tissue compromise. In the past 2 decades, clinical trials in patients after ischemic stroke focused on neuroprotection, but these strategies have failed in providing actual benefit. Vascular protection represents a new field to be explored in acute ischemic stroke in order to develop new approaches to therapeutic intervention.. We identified tactics likely to provide vascular protection in patients with ischemic stroke. These tactics are based on knowledge of the molecular processes involved.. The pathologic processes due to vascular injury after an occlusion of a cerebral artery can be separated into acute (those occurring within hrs), subacute (hrs to days), and chronic (days to mo). Targets for intervention can be identified for all three stages. In the acute phase, superoxide is the predominant mediator, followed by inflammatory mediators and proteases in the subacute phase. In the chronic phase, proapoptotic gene products have been implicated. Many already-marketed therapeutic agents (statins, angiotensin modulators, erythropoietin, minocycline, and thiazolidinediones), with proven safety in patients, have been shown to have activity against some of the key targets of vascular protection.. Currently available pharmacologic agents are poised for clinical trials of vascular protection after acute ischemic stroke.

Topics: Acute Disease; Angiotensin-Converting Enzyme Inhibitors; Brain; Brain Edema; Brain Ischemia; Cerebral Hemorrhage; Chronic Disease; Erythropoietin; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Minocycline; Stroke; Thiazolidinediones; Thrombolytic Therapy

This review discusses the potential usefulness of several selected polypeptide growth factors as treatments for stroke. Distinctions between global vs. focal cerebral ischemia, permanent vs. temporary focal ischemia, and acute stroke vs. stroke recovery are first discussed. Potential routes of administration of growth factors are also considered. The growth factors basic fibroblast growth factor (bFGF), osteogenic protein-1 (OP-1), vascular endothelial growth factor (Veg-f), erythropoietin (EPO), and granulocyte colony stimulating factor (G-CSF) all show potential usefulness in animal models of acute stroke and stroke recovery. Two of these factors, bFGF and EPO, have reached human clinical trials for acute stroke, and the data are discussed. Future directions in this field are also discussed.

Topics: Animals; Bone Morphogenetic Protein 7; Bone Morphogenetic Proteins; Brain Ischemia; Drug Administration Routes; Erythropoietin; Fibroblast Growth Factor 2; Granulocyte Colony-Stimulating Factor; Growth Substances; Humans; Mice; Rats; Stroke; Transforming Growth Factor beta; Vascular Endothelial Growth Factors

Several studies showed that anaemia is commonly observed in patients with Chronic Heart Failure (CHF) and is associated with worsened symptoms and survival. When anaemia in these patients is treated with erythropoietin (EPO), a significant improvement in cardiac function and symptoms was observed. Although it was originally believed that EPO specifically acted on haematopoietical cells, recent evidence demonstrated several non-haematopoietical effects. Ischaemia/reperfusion experiments in rat heart and brain showed large infarct reduction when treated with EPO. Other effects of EPO are related to its pro-angiogenic effects on endothelial cells, which could be of potential value in patients with ischaemic heart disease. These preclinical findings suggest that EPO may have potential effects in cardiovascular disease beyond correction of haemoglobin levels.

Topics: Anemia; Apoptosis; Cardiac Output, Low; Cardiovascular Diseases; Chronic Disease; Erythropoietin; Humans; Kidney Failure, Chronic; Myocardial Ischemia; Neovascularization, Pathologic; Recombinant Proteins; Stroke

With the increased life expectancy in western industrialized countries, the incidence and prevalence of brain diseases dramatically increased. Stroke and a wide spectrum of neuropsychiatric illnesses such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, traumatic head injury, and schizophrenia all lead to severe disability. However, targeted effective therapies for treatment of these diseases are lacking. Even more frustrating is the fact that we do not yet clearly understand the basic mechanisms underlying the disease processes in these conditions. We propose a hypothesis of loss of neuronal function via a final common deleterious pathway in this clinically very heterogeneous disease group. This review presents a novel neuroprotective concept for treatment of brain disease: Erythropoietin (EPO). EPO is a natural body-own-protein hormone that has been used for treatment of anemia for more than a decade. The neuroprotective approach using EPO in brain disease represents a totally new frontier. The "Göttingen EPO-stroke trial" represents the first effective use in man of a neuroprotective therapy in an acute brain disease while the experimental EPO therapy to combat cognitive decline in patients with schizophrenia will be introduced as an example of a neuroprotective strategy for a chronic brain disease.

Topics: Animals; Brain Diseases; Clinical Trials as Topic; Erythropoietin; Humans; Nerve Degeneration; Neuroprotective Agents; Regeneration; Schizophrenia; Stroke

Erythropoietin (EPO) is a cytokine which is commonly associated with its central role in erythropoiesis. The clinical applications of the recombinant hormone are currently restricted to the treatment of anemia in renal failure and cancer. Recent studies, however, have suggested a new role for EPO as an anti-inflammatory and neuroprotective drug. EPO and its receptor are expressed in neurons, glial cells and brain capillary endothelial cells, and the system is upregulated in conditions of cerebral ischaemia and hypoxia. Animal studies have now established that intracerebroventricular administration of recombinant EPO exerts neuroprotection in models of stroke. The mechanisms appear to involve an upregulation of specific anti-apoptotic and anti-inflammatory pathways. In addition, neurotrophic and angiogenetic effects of EPO may contribute in a long latency protection. Interestingly, also systemic administration of recombinant EPO ameliorates neuronal damage after brain ischaemia, and prevents the loss of autoregulation of cerebral blood flow following experimental subarachnoid haemorrhage. Recombinant human EPO is a safe and non-toxic drug, and clinical studies are currently investigating the neuroprotective potential of EPO in humans.

Topics: Animals; Brain Ischemia; Erythropoietin; Humans; Injections, Intraventricular; Neurons; Neuroprotective Agents; Receptors, Erythropoietin; Recombinant Proteins; Stroke

Sickle cell disease is numerically as common as thalassaemia. However, it affects relatively under privileged population i.e. tribal population belonging to economically poor class and having inadequate access to education and modern health facilities. A recent explosion acknowledged in understanding the pathogenesis of this disease has lead to newer dimensions in treatment. Some of these viz. prevention of overwhelming bacterial infection, present indications and controversies regarding blood transfusion, prevention of stroke, acute chest syndrome, hydroxyurea therapy--probably the best disease modifying agent at the moment, stem cell transplantation--a cure and certain promising experimental therapies including gene therapy have been discussed in this review.

Topics: Acute Disease; Adolescent; Anemia, Sickle Cell; Antisickling Agents; Bacterial Infections; Blood Transfusion; Child; Child, Preschool; Erythropoietin; Humans; Hydroxyurea; Infant; Infant, Newborn; Recombinant Proteins; Respiratory Tract Diseases; Stem Cell Transplantation; Stroke; Syndrome

The oxygen-dependent, renal cytokine eythropoietin (Epo) is well known to increase red cell production. Binding of Epo to the Epo receptor (EpoR) represses apoptosis of erythroid progenitor cells, thereby allowing their final maturation. We and others showed that Epo and its receptor are expressed in many other tissues, including brain, spinal cord, retina and testis. The presence of a blood barrier suggests that Epo plays a local role in these organs. Indeed, therapeutically applied or hypoxically induced Epo has been shown to reduce the infarct volume in various stroke animal models, to prevent retinal degeneration, and to ameliorate spinal cord injury. In a study conducted by Ehrenreich and colleagues, stroke patients treated with Epo showed reduced infarct volume, fast neurological recovery and improved clinical outcome. In analogy to its function on erythroid progenitor cells, this neuroprotective effect of Epo might be explained by repression of programmed cell death. Apart from neuroprotection, there is an assumption that Epo present in breast milk has the potential to protect against mother-to-infant transmission of HIV. When using Epo at high doses for longer time periods; however, care has to be taken to control the resulting chronic polycythemia that most probably caused enlarged cerebral infarct volumes in a transgenic mouse model that due to Epo-overexpression reached hematocrit levels of about 0.8. Overall, these data strongly support the notion that Epo will soon find new applications in the clinic.

Topics: Animals; Blood-Brain Barrier; Brain; Brain Injuries; Erythropoietin; Female; HIV Infections; Humans; Infectious Disease Transmission, Vertical; Ischemia; Male; Polycythemia; Pregnancy; Receptors, Erythropoietin; Recombinant Proteins; Retinal Vessels; Spinal Cord Ischemia; Stroke

Erythropoietin (EPO) is an endogenous cytokine with antiapoptotic, antiinflammatory, and neurotrophic properties. Apart from being produced by the kidney, liver, and spleen in response to hypoxia, EPO is highly expressed in the brain during development and after neuropathological insults. The observation that receptors for EPO are present on brain capillaries and glial capillary end-feet has suggested that circulating (plasma) EPO may be transferred into the brain. This review summarizes the increasing number of studies indicating that peripherally administered recombinant human (rHu) EPO crosses the blood-brain barrier. Moreover, several of these studies have shown that peripherally administered rHuEPO can protect against the damage caused by a diversity of neuropathological conditions such as (a) stroke, (b) head and spinal cord trauma, (c) inflammatory and demyelinating conditions, (d) toxin-induced epileptic seizures, and (e) retinal ischemia. While all these studies are based on experiments in animal models, the effectiveness of rHuEPO in ischemic stroke in human patients has recently been suggested in a proof-of-concept trial, which is also discussed.

Topics: Animals; Blood-Brain Barrier; Brain Injuries; Controlled Clinical Trials as Topic; Cross-Sectional Studies; Demyelinating Diseases; Disease Models, Animal; Erythropoietin; Evidence-Based Medicine; Female; Humans; Injections, Intramuscular; Injections, Intraperitoneal; Male; Mice; Neuroprotective Agents; Rabbits; Rats; Recombinant Proteins; Sensitivity and Specificity; Spinal Cord Injuries; Stroke; Treatment Outcome

Topics: Erythropoietin; Humans; Ischemic Preconditioning; Janus Kinase 2; Neurodegenerative Diseases; Neuroprotective Agents; NF-kappa B; Nitric Oxide; Protein-Tyrosine Kinases; Proto-Oncogene Proteins; Receptors, N-Methyl-D-Aspartate; Signal Transduction; Stroke

Erythropoietin and its receptor function as primary mediators of the normal physiological response to hypoxia. Erythropoietin is recognized for its central role in erythropoiesis, but studies in which recombinant human erythropoietin (epoetin alfa) is injected directly into ischaemic rodent brain show that erythropoietin also mediates neuroprotection. Abundant expression of the erythropoietin receptor has been observed at brain capillaries, which could provide a route for circulating erythropoietin to enter the brain. In confirmation of this hypothesis, systemic administration of epoetin alfa before or up to 6 h after focal brain ischaemia reduced injury by 50-75%. Epoetin alfa also limited the extent of concussive brain injury, the immune damage in experimental autoimmune encephalomyelitis and excitotoxicity induced by kainate. Thus, systemically administered epoetin alfa in animal models has neuroprotective effects, demonstrating its potential use after brain injury, trauma and multiple sclerosis. It is evident that erythropoietin has biological activities in addition to increasing red cell mass. Given the excellent safety profile of epoetin alfa, clinical trials evaluating systemically administered epoetin alfa as a general neuroprotective treatment are warranted.

Topics: Acute Disease; Animals; Autoimmune Diseases; Brain; Brain Ischemia; Cerebral Cortex; Encephalitis; Epoetin Alfa; Erythropoietin; Humans; Kainic Acid; Neuroprotective Agents; Recombinant Proteins; Stroke; Wounds, Nonpenetrating

By definition, idiopathic erythrocytosis (IE) applies to a group of patients characterised by having a measured RCM above their predicted normal range (an absolute erythrocytosis) and following investigation do not have a form of primary or secondary erythrocytosis. Patients with IE are heterogenous. The possibilities include physiological variation, 'early' polycythaemia vera (10-15% develop clear features of PV over a few years), unrecognized congenital erythrocytosis, unrecognized or unrecognizable secondary acquired erythrocytosis or a currently undescribed form of primary or secondary erythrocytosis. Patients are more commonly male with a median age at presentation of 55-60 years. Approximately half of the patients present with vascular occlusive complications. Retrospective evidence indicates that vascular occlusion occurs less frequently when the PCV is controlled at normal levels. Venesection is the treatment of choice to lower the PCV. As a general approach to management, all patients with a PCV above 0.54 should be venesected to a PCV less than 0.45. This target PCV should also apply to patients with lesser degrees of raised PCV who have additional other risk factors for vascular occlusion.

Topics: Aged; Arterial Occlusive Diseases; Bone Marrow; Chlorambucil; Diagnosis, Differential; Endocrine System Diseases; Erythrocyte Volume; Erythroid Precursor Cells; Erythropoietin; Genetic Predisposition to Disease; Humans; Hypoxia; Kidney Diseases; Leukemia; Leukemia, Radiation-Induced; Middle Aged; Phosphorus Radioisotopes; Polycythemia; Polycythemia Vera; Receptors, Erythropoietin; Sequence Deletion; Smoking; Stroke

Neuroprotection as a means to prevent or oppose pathological neuronal loss in central nervous system disease of various pathophysiological origins represents a novel therapeutic approach. This approach is supported by extensive experimental evidence on cell culture and animal studies demonstrating beneficial effects of growth factors on neuronal survival and functional recovery. The clinical use of neuroprotective agents has been hampered by the toxicity of many of the compounds that showed promising therapeutic potential in animal studies. The focus of this review is on a novel neuroprotective approach with erythropoietin, a hematopoietic growth factor that: 1) is expressed in the human central nervous system, 2) is hypoxia-inducible, 3) has demonstrated remarkable neuroprotective potential in cell culture and animal models of disease, 4) has multiple protective effects (antiapoptotic, neurotrophic, antioxidant, angiogenic), and 5) is a clinically extremely well tolerated compound.

Topics: Animals; Brain; Clinical Trials as Topic; DNA-Binding Proteins; Erythropoietin; Gene Expression Regulation; Humans; Hypoxia-Inducible Factor 1; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; Neuroprotective Agents; Nuclear Proteins; Receptors, Erythropoietin; Recombinant Proteins; Stroke; Transcription Factors

In patients with acute symptomatic stroke, reinforcement of transdural angiogenesis using multiple burr hole (MBH) procedures after EPO (erythropoietin) treatment has rarely been addressed. We aimed to investigate the efficacy and safety of cranial MBH procedures under local anesthesia for augmenting transdural revascularization after EPO treatment in patients with stroke with perfusion impairments.. This prospective, randomized, blinded-end point trial recruited patients with acute ischemic stroke with a perfusion impairment of grade ≥2 within 14 days of symptom onset, steno-occlusive mechanisms on imaging examinations, and absence of transdural collaterals on transfemoral cerebral angiography. Patients were randomly assigned to receive MBH + EPO or MBH alone. The primary and secondary outcomes were revascularization success (trans-hemispheric and trans-burr hole) at 6 months and adverse events, respectively.. We evaluated 42 of the 44 targeted patients, with 2 patients lost to follow-up. The combined and MBH-only (n=21 each) groups showed no differences in demographic characteristics and baseline perfusion parameters. Significantly, more cases of trans-hemispheric (19/21 [90.5%] versus 12/21 [57.1%]) and trans-burr hole (42/58 [72.4%] versus 30/58 [51.7%]) revascularization and significant improvements in perfusion parameters were observed in the combined group relative to the MBH-only group. No differences in treatment-related complications were observed between groups. Even after adjustment for potential covariates, EPO usage was an independent factor of successful hemispheric revascularization in this study (odds ratio, 6.41 [95% CI, 1.08-38.02]).. The combination of MBH and EPO is safe and feasible for reinforcing transdural revascularization in acute steno-occlusive patients with perfusion impairments.. URL: https://www.. gov; Unique identifier: NCT02603406.

Topics: Cerebral Revascularization; Epoetin Alfa; Erythropoietin; Humans; Ischemic Stroke; Prospective Studies; Stroke; Treatment Outcome; Trephining

Mortality and disability following ischemic stroke (IS) remains unacceptably high with respect to the conventional therapies. This study tested the effect of erythropoietin (EPO) on long-term neurological outcome in patients after acute IS. This study aimed to evaluate the safety and efficacy of two consecutive doses of EPO (5,000 IU/dose, subcutaneously administered at 48 hours and 72 hours after acute IS) on improving the 90-day combined endpoint of recurrent stroke or death that has been previously reported. A secondary objective was to evaluate the long-term (that is, five years) outcome of patients who received EPO.. This was a prospective, randomized, placebo-controlled trial that was conducted between October 2008 and March 2010 in a tertiary referral center. IS stroke patients who were eligible for EPO therapy were enrolled into the study.. The results showed that long-term recurrent stroke and mortality did not differ between group 1 (placebo-control; n = 71) and group 2 (EPO-treated; n = 71). Long-term Barthel index of <35 (defining a severe neurological deficit) was lower in group 2 than group 1 (P = 0.007). Multiple-stepwise logistic-regression analysis showed that EPO therapy was significantly and independently predictive of freedom from a Barthel index of <35 (P = 0.029). Long-term major adverse neurological event (MANE; defined as: death, recurrent stroke, or long-term Barthel index < 35) was lower in group 2 than group 1 (P = 0.04). Log-Rank test showed that MANE-free rate was higher in group 2 than group 1 (P = 0.031). Multiple-stepwise Cox-regression analysis showed that EPO therapy and higher Barthel Index at day 90 were independently predictive of freedom from long-term MANE (all P <0.04).. EPO therapy significantly improved long-term neurological outcomes in patients after IS.. ISRCTN71371114 . Registered 10 October 2008.

Topics: Aged; Brain Ischemia; Endothelial Progenitor Cells; Erythropoietin; Female; Humans; Male; Middle Aged; Multivariate Analysis; Neuroprotective Agents; Prospective Studies; Stroke; Time Factors; Treatment Outcome

Renin-angiotensin system (RAS) inhibition has proven to be helpful in reducing cardiovascular and kidney disease progression in the general population; whether kidney transplant patients would derive similar benefits is unknown. RAS inhibition also reduces posttransplantation erythrocytosis in kidney transplant recipients, but its effect on hemoglobin (Hb) levels in patients without posttransplantation erythrocytosis is unclear.. The Specific Management of Anemia and Hypertension in Renal Transplant (SMAhRT) recipients study was designed to examine the cardiovascular benefits of RAS blockade with telmisartan 80 mg versus placebo, and Hb management with darbepoetin α in a randomized, double-blind, single-center controlled trial in 2,000 patients over 3 years. The primary efficacy variable was a composite of all-cause mortality, myocardial infarction or stroke.. The SMAhRT study was stopped prematurely due to a lower than expected event rate. At that point, 136 patients were enrolled and were followed for a mean duration of 15 months. The use of RAS blockade was not associated with an increased risk of adverse events such as worsening anemia or hyperkalemia. Likewise, the correction of Hb with darbepoetin was not associated with any increase in thrombotic events.. This study provides insight into the safety of RAS inhibition and Hb correction with an erythrocyte-stimulating agent in kidney transplant recipients.

Topics: Adult; Aged; Aged, 80 and over; Anemia; Benzimidazoles; Benzoates; Darbepoetin alfa; Double-Blind Method; Erythropoietin; Female; Hemoglobins; Humans; Hypertension; Kidney Transplantation; Male; Middle Aged; Myocardial Infarction; Renin-Angiotensin System; Stroke; Telmisartan; Treatment Outcome; Young Adult

Preclinical studies suggest that growth factors in the early days after stroke improve final outcome. A prior study found three doses of human choriogonadotropin alfa followed by three doses of erythropoietin to be safe after stroke in humans. A proof of concept trial (REGENESIS) was initiated but placed on regulatory hold during review of an erythropoietin neuroprotective trial. Due to financial constraints, the trial was largely moved to India, using lower erythropoietin doses, as the REGENESIS-LED trial.. Entry criteria included National Institutes of Health Stroke Scale 8-20, supratentorial ischemic stroke, and 24-48 h poststroke at start of therapy. Patients were randomized to three QOD doses of subcutaneous human choriogonadotropin alfa followed by three QD doses of intravenous erythropoietin (three escalating dose cohorts, 4000-20,000 IU/dose) vs. placebo. Primary outcomes were safety and neurological recovery.. The study was halted early by the sponsor after 96 enrollees. There was no significant difference across treatment groups in the proportion of patients experiencing death, serious adverse events, or any adverse event. There was no significant difference in National Institutes of Health Stroke Scale score change from baseline to Day 90 between placebo and active treatment, whether active cohorts were analyzed together or separately, and no exploratory secondary measure of neurological recovery showed a significant difference between groups.. Administration of human choriogonadotropin alfa followed by erythropoietin is safe after a new ischemic stroke. At the doses studied, placebo and active groups did not differ significantly in neurological recovery. Study limitations, such as the use of multiple assessors, differences in rehabilitation care, and being underpowered to show efficacy, are discussed.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Brain Ischemia; Chorionic Gonadotropin; Cohort Studies; Double-Blind Method; Epoetin Alfa; Erythropoietin; Female; Hematinics; Humans; International Cooperation; Magnetic Resonance Imaging; Male; Middle Aged; Nervous System Diseases; Outcome Assessment, Health Care; Recombinant Proteins; Severity of Illness Index; Stroke; Time Factors; Tomography Scanners, X-Ray Computed; Treatment Outcome; Young Adult

Patients with systolic heart failure and anemia have worse symptoms, functional capacity, and outcomes than those without anemia. We evaluated the effects of darbepoetin alfa on clinical outcomes in patients with systolic heart failure and anemia.. In this randomized, double-blind trial, we assigned 2278 patients with systolic heart failure and mild-to-moderate anemia (hemoglobin level, 9.0 to 12.0 g per deciliter) to receive either darbepoetin alfa (to achieve a hemoglobin target of 13 g per deciliter) or placebo. The primary outcome was a composite of death from any cause or hospitalization for worsening heart failure.. The primary outcome occurred in 576 of 1136 patients (50.7%) in the darbepoetin alfa group and 565 of 1142 patients (49.5%) in the placebo group (hazard ratio in the darbepoetin alfa group, 1.01; 95% confidence interval, 0.90 to 1.13; P=0.87). There was no significant between-group difference in any of the secondary outcomes. The neutral effect of darbepoetin alfa was consistent across all prespecified subgroups. Fatal or nonfatal stroke occurred in 42 patients (3.7%) in the darbepoetin alfa group and 31 patients (2.7%) in the placebo group (P=0.23). Thromboembolic adverse events were reported in 153 patients (13.5%) in the darbepoetin alfa group and 114 patients (10.0%) in the placebo group (P=0.01). Cancer-related adverse events were similar in the two study groups.. Treatment with darbepoetin alfa did not improve clinical outcomes in patients with systolic heart failure and mild-to-moderate anemia. Our findings do not support the use of darbepoetin alfa in these patients. (Funded by Amgen; RED-HF ClinicalTrials.gov number, NCT00358215.).

Topics: Aged; Anemia; Darbepoetin alfa; Double-Blind Method; Erythropoietin; Female; Heart Failure, Systolic; Hematinics; Hemoglobins; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Proportional Hazards Models; Shock, Septic; Stroke; Thromboembolism; Treatment Failure

Recombinant erythropoietin has become a routine component of care of patients with chronic kidney disease reducing the need for blood transfusions but raising the risks for cardiovascular events. We undertook this secondary analysis of subjects enrolled in the Correction of Hemoglobin and Outcomes in Renal Insufficiency (CHOIR) trial to examine the interrelationships between epoetin-alfa maintenance doses utilized and achieved hemoglobin (Hb) irrespective of treatment target and randomized allocation.. We performed a post hoc analysis from the CHOIR trial. Inclusion criteria were Hb <11.0 g/dl and estimated glomerular filtration rates of 15-50 ml/min/1.73 m(2). To be included in the present analysis, subjects needed to be free of the composite event at 4 months, receive epoetin-alfa, and have ≥1 postbaseline Hb measurement. The mean weekly dose of epoetin-alfa received up to the time of first event or censure was the main exposure variable, while the achieved Hb at month 4 was the confounder representing the subject's underlying response to treatment. The primary outcome was the composite of death, heart failure hospitalization, stroke, or myocardial infarction. A Cox proportional hazard regression model was used in time-to-event analysis.. Among 1,244 subjects with complete data, the average weekly dose of epoetin-alfa ranged 143.3-fold from 133 to 19,106 units/week at the time of first event or censure. Cox proportional hazard analysis found that those in the middle tertile of Hb achieved (>11.5 to <12.7 g/dl) and the lowest tertile of epoetin-alfa dose exposure level (<5,164 units/week) had the lowest risk. Irrespective of Hb achieved, the relative risk in the highest tertile (>10,095 units/week) of epoetin-alfa dose exposure level was significantly escalated (hazard ratios ranged from 2.536 to 3.572, p < 0.05, when compared to the group of middle Hb tertile and lowered dose tertile). In a multivariable model that adjusted for achieved Hb, albumin, cholesterol, age, prior heart failure, prior stroke, prior deep venous thrombosis, atrial fibrillation or malignancy, the average weekly dose had a significant (p = 0.005) relative risk of 1.067 per 1,000 units of epoetin-alfa for the primary end point.. In the CHOIR trial, average epoetin-alfa doses >10,095 units/week were associated with increased risks for cardiovascular events irrespective of the Hb achieved within the first 4 months of treatment. These data suggest the weekly epoetin-alfa dose and not the Hb achieved was a principal determinant in the primary outcome observed implicating a cardiovascular toxicity of this erythrocyte-stimulating agent.

Topics: Aged; Aged, 80 and over; Anemia; Dose-Response Relationship, Drug; Epoetin Alfa; Erythropoietin; Female; Heart Failure; Hematinics; Hemoglobins; Humans; Male; Middle Aged; Myocardial Infarction; Proportional Hazards Models; Recombinant Proteins; Renal Insufficiency, Chronic; Risk Factors; Stroke; Treatment Outcome

In the German Multicenter Erythropoietin (EPO) Stroke Trial, patients not receiving thrombolysis most likely benefited from EPO on clinical recovery, whereas a combination of rtPA and EPO was associated with increased mortality. We investigated whether the combination of rtPA and EPO increased release of the endogenous NO synthase inhibitor asymmetric dimethylarginine (ADMA), and thereby potentially deteriorated ischemic stroke outcome, as suggested from experimental data.. ADMA was determined in serum samples from 90 patients of the German Multicenter EPO Stroke Trial taken at days 1 (within 6 hours after symptom onset), 2, 3, 4, and 7 after stroke using high-performance liquid chromatography-tandem mass spectrometry. ADMA was analyzed for the different treatment groups (EPO, n=25; placebo, n=30; rtPA+placebo, n=18; EPO+rtPA, n=17). Clinical outcome was expressed as difference between National Institutes of Health Stroke Scale at baseline and 90 days.. ADMA levels significantly increased during the observation time in EPO, EPO+rtPA, and placebo groups (P<0.05). A treatment effect on ADMA levels was revealed by repeated measures ANOVA only in the rtPA+placebo group (P=0.027). Here, ADMA levels were decreased compared with the placebo group (P<0.05). Both the EPO and the rtPA+placebo groups in the Hannover subgroup of the EPO trial had better outcome than the placebo group (P<0.05).. Our data underscore the potential benefit of EPO in ischemic stroke. The hypothesis from experimental data, that EPO treatment increases ADMA in stroke patients, was disproved. Further studies are needed to clarify whether decreased ADMA might contribute to therapeutic rtPA effects.

Topics: Acute Disease; Aged; Aged, 80 and over; Arginine; Double-Blind Method; Drug Therapy, Combination; Erythropoietin; Female; Humans; Male; Middle Aged; Severity of Illness Index; Stroke; Thrombolytic Therapy; Tissue Plasminogen Activator; Treatment Outcome

Descending aortic (DA) surgery poses a high risk for spinal and cerebral infarction and routine use of lumbar drains allows for measurement of CSF markers of neurologic injury. Erythropoiesis medications have extensive preclinical data demonstrating neuroprotection. We hypothesized that prophylactic darbepoetin alfa (DARB) given before surgery reduces neurologic injury in patients undergoing DA repair.. We performed a prospective adaptive dose-finding trial of prophylactic DARB ( www.clinicaltrials.gov NCT00647998) that terminated prematurely following publication of an erythropoietin stroke study showing possible harm. Enrollment halted before dose adjustments; nine patients each received 1 mg/kg IV DARB immediately before surgery. A prospective cohort of nine untreated patients was subsequently obtained for comparison. The primary outcome of death or neurologic impairment at discharge occurred in 1/9 (11 %) DARB patients and 3/9 (33 %) controls (p = 0.58). There were no statistical differences in changes of CSF biomarkers from baseline to 48 h comparing DARB patients to controls: S100β, median 214 versus 260 ng/ml (p = 0.69); glial fibrillary acidic protein (GFAP), median 0.022 versus 0.58 ng/ml (p = 0.45). In patients with early perioperative neurologic ischemia, there were greater changes in CSF biomarkers, compared to those without ischemia: S100β, median 2301 versus 124 ng/ml (p = 0.04); GFAP, median 31.78 versus 0.31 ng/ml (p = 0.34).. There were no significant effects of prophylactic DARB on clinical outcome or CSF markers of neurologic injury in this pilot study, although all point estimates favored treatment. DA repair is a promising model of prophylactic neuroprotection.

Topics: Aged; Aorta; Darbepoetin alfa; Early Termination of Clinical Trials; Erythropoietin; Female; Humans; Male; Middle Aged; Neuroprotective Agents; Pilot Projects; Prospective Studies; Spinal Cord Ischemia; Stroke; Treatment Outcome

Circulating endothelial cells (CECs) are a novel and valuable marker of endothelial damage in a variety of vascular disorders. There is limited information as to CEC counts and the time course of CECs in subtypes of stroke.. We studied 49 patients with stroke (18 with atherothrombotic infarction in the territory of the middle cerebral artery, 16 with cardioembolic stroke, and 15 with lacunar stroke). We also included 16 healthy controls and 64 disease controls. CECs were isolated and enumerated with lectin-augmented CD146-driven immunomagnetic isolation. Neurologic deficit was assessed with the European Stroke Scale (ESS) and the National Institutes of Health Stroke Scale (NIHSS). Recovery was assessed with the modified Rankin scale (mRS).. Healthy controls had low numbers of CECs (median, 8 cells/mL; mean, 9 cells/mL; range, 0-16 cells/mL; n = 16). Patients with stroke had markedly elevated numbers of CECs at presentation. Patients with atherothrombotic infarction had 32 cells per milliliter (mean, 42 cells/mL; range, 24-116 cells/mL; n = 18; P < .001 when compared to controls). Patients with lacunar stroke had 68 cells per milliliter (mean, 68 cells/mL; range, 8-144 cells/mL; n = 15; P < .001 when compared to controls). Patients with cardioembolic stroke had 46 cells per milliter (mean, 54 cells/mL; range, 24-116 cells/mL; n = 16; P < .001 when compared to healthy controls). There was a tendency towards higher numbers of CECs in lacunar stroke. The number of CECs peaked at day 7 in patients with atherothrombotic infarction and came back to normal at day 90. In contrast, CECs in patients with acute lacunar stroke and cardioembolic stroke decreased progressively until day 90.. CECs are markers of endothelial damage and/or repair in stroke. Differences during the course of disease are likely to reflect different pathophysiology.

Topics: Adult; Aged; Aged, 80 and over; Biomarkers; CD146 Antigen; Cell Count; Disability Evaluation; Double-Blind Method; Endothelial Cells; Erythropoietin; Female; Germany; Humans; Immunomagnetic Separation; Magnetic Resonance Imaging; Male; Middle Aged; Recovery of Function; Severity of Illness Index; Stroke; Time Factors; Tomography, X-Ray Computed; Treatment Outcome

Currently, no data on the optimal time point after acute ischemic stroke (IS) at which high-sensitivity C-reactive protein (hs-CRP) level is most predictive of unfavorable outcome. We tested the hypothesis that hs-CRP levels during both acute (48 h after IS) and convalescent (21 days after IS) phases are equally important in predicting 90-day clinical outcome after acute IS. We further evaluated the impact of erythropoietin (EPO), an anti-inflammatory agent, on level of hs-CRP after acute IS.. Totally 160 patients were prospectively randomized to receive either EPO therapy (group 1, n = 80) (5,000 IU each time, subcutaneously) at 48 h and 72 h after acute IS, or placebo (group 2, n = 80). Serum level of hs-CRP was determined using ELISA at 48 h and on day 21 after IS and once in 60 healthy volunteers.. Serum level of hs-CRP was substantially higher in all patients with IS than in healthy controls at 48 h and day 21 after IS (all p < 0.001). Levels of hs-CRP did not differ between group 1 and 2 at 48 h and day 21 after IS (all p > 0.5). Multivariate analysis showed that hs-CRP levels (at 48 h and day 21) were independently predictive of 90-day major adverse neurological event (MANE) (defined as recurrent stroke, NIHSS≥8, or death) (all p < 0.03), whereas EPO therapy was independently predictive of reduced 90-day MANE (all p < 0.02).. EPO therapy which was independently predictive of freedom from 90-day MANE did not alter the crucial role of hs-CRP levels measured at 48 h and 21-day in predicting unfavorable clinical outcome after IS.

Topics: Aged; Brain Ischemia; C-Reactive Protein; Case-Control Studies; Convalescence; Erythropoietin; Female; Humans; Logistic Models; Male; Middle Aged; Multivariate Analysis; ROC Curve; Statistics, Nonparametric; Stroke; Treatment Outcome

Erythropoietin (EPO) enhances the circulating level of endothelial progenitor cells (EPCs), which has been reported to be associated with prognostic outcome in ischemic stroke (IS) patients. The aim of this study was to evaluate the time course of circulating EPC level and the impact of EPO therapy on EPC level and clinical outcome in patients after acute IS.. In total, 167 patients were prospectively randomized to receive either EPO therapy (group 1) (5,000 IU each time, subcutaneously) at 48 h and 72 h after acute IS, or serve as placebo (group 2). The circulating level of EPCs (double-stained markers: CD31/CD34 (E1), CD62E/CD34 (E2) and KDR/CD34 (E3)) was determined using flow cytometry at 48 h and on days 7 and 21 after IS. EPC level was also evaluated once in 60 healthy volunteers.. Circulating EPC (E1 to E3) level at 48 h after IS was remarkably higher in patients than in control subjects (P < 0.02). At 48 h and on Day 7 after IS, EPC (E1 to E3) level did not differ between groups 1 and 2 (all P > 0.1). However, by Day 21, EPC (E1 to E3) level was significantly higher in group 1 than in group 2 (all P < 0.03). Additionally, 90-day recurrent stroke rate was notably lower in group 1 compared with group 2 (P = 0.022). Multivariate analysis demonstrated that EPO therapy (95% confidence interval (CI), 0.153 to 0.730; P = 0.006) and EPC (E3) (95% CI, 0.341 to 0.997; P = 0.049) levels were significantly and independently predictive of a reduced 90-day major adverse neurological event (MANE) (defined as recurrent stroke, National Institutes of Health Stroke scale ≥8, or death).. EPO therapy significantly improved circulating EPC level and 90-day MANE.. ISRCTN: ISRCTN96340690.

Topics: Aged; Biomarkers; Endothelial Cells; Erythropoietin; Female; Hematinics; Humans; Male; Middle Aged; Predictive Value of Tests; Prognosis; Prospective Studies; Stem Cells; Stroke; Time Factors; Treatment Outcome

Acute ST-segment elevation myocardial infarction (STEMI) is a leading cause of morbidity and mortality. In experimental models of MI, erythropoietin reduces infarct size and improves left ventricular (LV) function.. To evaluate the safety and efficacy of a single intravenous bolus of epoetin alfa in patients with STEMI.. A prospective, randomized, double-blind, placebo-controlled trial with a dose-escalation safety phase and a single dose (60,000 U of epoetin alfa) efficacy phase; the Reduction of Infarct Expansion and Ventricular Remodeling With Erythropoietin After Large Myocardial Infarction (REVEAL) trial was conducted at 28 US sites between October 2006 and February 2010, and included 222 patients with STEMI who underwent successful percutaneous coronary intervention (PCI) as a primary or rescue reperfusion strategy.. Participants were randomly assigned to treatment with intravenous epoetin alfa or matching saline placebo administered within 4 hours of reperfusion.. Infarct size, expressed as percentage of LV mass, assessed by cardiac magnetic resonance (CMR) imaging performed 2 to 6 days after study medication administration (first CMR) and again 12 ± 2 weeks later (second CMR).. In the efficacy cohort, the infarct size did not differ between groups on either the first CMR scan (n = 136; 15.8% LV mass [95% confidence interval {CI}, 13.3-18.2% LV mass] for the epoetin alfa group vs 15.0% LV mass [95% CI, 12.6-17.3% LV mass] for the placebo group; P = .67) or on the second CMR scan (n = 124; 10.6% LV mass [95% CI, 8.4-12.8% LV mass] vs 10.4% LV mass [95% CI, 8.5-12.3% LV mass], respectively; P = .89). In a prespecified analysis of patients aged 70 years or older (n = 21), the mean infarct size within the first week (first CMR) was larger in the epoetin alfa group (19.9% LV mass; 95% CI, 14.0-25.7% LV mass) than in the placebo group (11.7% LV mass; 95% CI, 7.2-16.1% LV mass) (P = .03). In the safety cohort, of the 125 patients who received epoetin alfa, the composite outcome of death, MI, stroke, or stent thrombosis occurred in 5 (4.0%; 95% CI, 1.31%-9.09%) but in none of the 97 who received placebo (P = .04).. In patients with STEMI who had successful reperfusion with primary or rescue PCI, a single intravenous bolus of epoetin alfa within 4 hours of PCI did not reduce infarct size and was associated with higher rates of adverse cardiovascular events. Subgroup analyses raised concerns about an increase in infarct size among older patients.. clinicaltrials.gov Identifier: NCT00378352.

Topics: Adult; Age Factors; Angioplasty, Balloon, Coronary; Double-Blind Method; Epoetin Alfa; Erythropoietin; Female; Hematinics; Humans; Injections, Intravenous; Magnetic Resonance Imaging; Male; Middle Aged; Myocardial Infarction; Myocardial Reperfusion; Myocardium; Placebos; Recombinant Proteins; Stents; Stroke; Thrombosis; Treatment Outcome; Ventricular Function, Left; Ventricular Remodeling

The German Multicenter EPO Stroke Trial, which investigated safety and efficacy of erythropoietin (EPO) treatment in ischemic stroke, was formally declared a negative study. Exploratory subgroup analysis, however, revealed that patients not receiving thrombolysis most likely benefited from EPO during clinical recovery, a result demonstrated in the findings of the Göttingen EPO Stroke Study. The present work investigated whether the positive signal on clinical outcome in this patient subgroup was mirrored by respective poststroke biomarker profiles. All patients of the German Multicenter EPO Stroke Trial nonqualifying for thrombolysis were included if they (a) were treated per protocol and (b) had at least two of the five follow-up blood samples for circulating damage markers drawn (n = 163). The glial markers S100B and glial fibrillary acid protein (GFAP) and the neuronal marker ubiquitin C-terminal hydrolase (UCH-L1) were measured by enzyme-linked immunosorbent assay in serum on d 1, 2, 3, 4 and 7 poststroke. All biomarkers increased poststroke. Overall, EPO-treated patients had significantly lower concentrations (area under the curve) over 7 d of observation, as reflected by the composite score of all three markers (Cronbach α = 0.811) and by UCH-L1. S100B and GFAP showed a similar tendency. To conclude, serum biomarker profiles, as an outcome measure of brain damage, corroborate an advantageous effect of EPO in ischemic stroke. In particular, reduction in the neuronal damage marker UCH-L1 may reflect neuroprotection by EPO.

Topics: Aged; Area Under Curve; Biomarkers; Brain Ischemia; Epoetin Alfa; Erythropoietin; Female; Humans; Male; Neuroprotective Agents; Recombinant Proteins; Stroke; Treatment Outcome

More strokes were observed in the Trial to Reduce Cardiovascular Events With Aranesp Therapy (TREAT) among patients assigned to darbepoetin alfa. We sought to identify baseline characteristics and postrandomization factors that might explain this association.. A multivariate logistic regression model was used to identify baseline predictors of stroke in 4038 patients with diabetes mellitus, chronic kidney disease, and anemia randomized to receive darbepoetin alfa or placebo. To determine whether postrandomization blood pressure, hemoglobin level, platelet count, or treatment dose were responsible for the increased risk related to darbepoetin alfa, we performed a nested case-control analysis (1:10 matching) identifying nonstroke controls with propensity matching. The risk of stroke was doubled with darbepoetin alfa. Overall, 154 patients had a stroke, 101/2012 (5.0%) in the darbepoetin alfa arm and 53/2026 (2.6%) in the placebo arm (hazard ratio 1.9; 95% confidence interval, 1.4-2.7). Independent predictors of stroke included assignment to darbepoetin alfa (odds ratio 2.1; 95% confidence interval, 1.5-2.9), history of stroke (odds ratio 2.0; 95% confidence interval, 1.4-2.9), more proteinuria, and known cardiovascular disease. In patients assigned to darbepoetin alfa, postrandomization systolic and diastolic blood pressure, hemoglobin level, platelet count, and darbepoetin alfa dose did not differ between those with and without stroke. Additional sensitivity analyses using maximal values, latest values, or changes over varying periods of exposure yielded similar results.. The 2-fold increase in stroke with darbepoetin alfa in TREAT could not be attributed to any baseline characteristic or to postrandomization blood pressure, hemoglobin, platelet count, or dose of treatment. These readily identifiable factors could not be used to mitigate the risk of darbepoetin alfa-related stroke.. http://www.clinicaltrials.gov. Unique identifier: NCT00093015.

Topics: Aged; Anemia; Case-Control Studies; Darbepoetin alfa; Diabetes Mellitus, Type 2; Erythropoietin; Female; Follow-Up Studies; Hematinics; Humans; Incidence; Logistic Models; Male; Middle Aged; Multivariate Analysis; Predictive Value of Tests; Prospective Studies; Renal Insufficiency, Chronic; Risk Factors; Risk Reduction Behavior; Stroke; Treatment Outcome

Animal data suggest the use of beta-human chorionic gonadotropin followed by erythropoietin to promote brain repair after stroke. The current study directly translated these results by evaluating safety of this sequential growth factor therapy through a 3-center, single-dose, open-label, noncontrolled, Phase IIa trial.. Patients with ischemic stroke 24 to 48 hours old and National Institutes of Health Stroke Scale score of 6 to 24 started a 9-day course of beta-human chorionic gonadotropin (once daily on Days 1, 3, and 5 of study participation) followed by erythropoietin (once daily on Days 7, 8, and 9 of study participation). This study also evaluated performance of serially measured domain-specific end points.. A total of 15 patients were enrolled. Two deaths occurred, neither related to study medications. No safety concerns were noted among clinical or laboratory measures, including screening for deep vein thrombosis and serial measures of serum hemoglobin. In several instances, domain-specific end points provided greater insight into impairments as compared with global outcome measures.. Results support the safety of this sequential, 2-growth factor therapy initiated 24 to 48 hours after stroke onset.

Topics: Adult; Aged; Aged, 80 and over; Brain Ischemia; Chorionic Gonadotropin, beta Subunit, Human; Drug Therapy, Combination; Erythropoietin; Female; Hemoglobins; Humans; Male; Middle Aged; Stroke; Venous Thrombosis; Young Adult

Erythropoietin improves myocardial function in experimental models of myocardial infarction. The aim of the present study was to determine the value of erythropoietin in patients with acute ST-elevation myocardial infarction.. This randomized, double-blind study included 138 patients admitted with acute ST-elevation myocardial infarction and treated with primary percutaneous coronary intervention. Patients were randomly assigned to receive epoetin-β (3.33×104 U, n=68) or placebo (n=70) immediately and at 24 and 48 hours after percutaneous coronary intervention. The primary end point was left ventricular ejection fraction after 6 months measured by MRI. Other end points included infarct size at 5 days and 6 months. Clinical adverse events (death, recurrent myocardial infarction, stroke, and infarct-related artery revascularization) were investigated at 30 days and 6 months. Left ventricular ejection fraction at 6-month follow-up was 52.0±9.1% in the erythropoietin group compared with 51.8±9.3% in the placebo group (P=0.92). Five days after percutaneous coronary intervention, left ventricular ejection fraction was 49.4±8.0% in the erythropoietin group and 50.8±7.3% in the placebo group (P=0.32); infarct size was 26.8±20.9% and 28.3±24.4% (P=0.76) and decreased to 17.3±14.3% and 20.9±16.4% at 6-month follow-up (P=0.27). The cumulative 6-month incidence of death, recurrent myocardial infarction, stroke or target vessel revascularization was 13.2% in the erythropoietin group and 5.7% in the placebo group (hazard ratio, 2.36; 95% confidence interval, 0.73 to 7.66; P=0.15).. In patients with acute ST-elevation myocardial infarction treated with primary percutaneous coronary intervention, erythropoietin treatment did not improve left ventricular ejection fraction or reduce infarct size but may increase clinical adverse events.. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00390832.

Topics: Aged; Angioplasty; Double-Blind Method; Electrocardiography; Erythropoietin; Follow-Up Studies; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Myocardium; Recurrence; Stroke; Stroke Volume; Survival Analysis; Treatment Outcome

Non–placebo-controlled trials of erythropoiesis-stimulating agents (ESAs) comparing lower and higher hemoglobin targets in patients with chronic kidney disease indicate that targeting of a lower hemoglobin range may avoid ESA-associated risks. However, target-based strategies are confounded by each patient's individual hematopoietic response.. We assessed the relationship among the initial hemoglobin response to darbepoetin alfa after two weight-based doses, the hemoglobin level achieved after 4 weeks, the subsequent darbepoetin alfa dose, and outcomes in 1872 patients with chronic kidney disease and type 2 diabetes mellitus who were not receiving dialysis. We defined a poor initial response to darbepoetin alfa (which occurred in 471 patients) as the lowest quartile of percent change in hemoglobin level (<2%) after the first two standardized doses of the drug.. Patients who had a poor initial response to darbepoetin alfa had a lower average hemoglobin level at 12 weeks and during follow-up than did patients with a better hemoglobin response (a change in hemoglobin level ranging from 2 to 15% or more) (P<0.001 for both comparisons), despite receiving higher doses of darbepoetin alfa (median dose, 232 μg vs. 167 μg; P<0.001). Patients with a poor response, as compared with those with a better response, had higher rates of the composite cardiovascular end point (adjusted hazard ratio, 1.31; 95% confidence interval [CI], 1.09 to 1.59) or death (adjusted hazard ratio, 1.41; 95% CI, 1.12 to 1.78).. A poor initial hematopoietic response to darbepoetin alfa was associated with an increased subsequent risk of death or cardiovascular events as doses were escalated to meet target hemoglobin levels. Although the mechanism of this differential effect is not known, these findings raise concern about current target-based strategies for treating anemia in patients with chronic kidney disease. (Funded by Amgen; ClinicalTrials.gov number, NCT00093015.)

Topics: Aged; Anemia; Cardiovascular Diseases; Chi-Square Distribution; Darbepoetin alfa; Diabetes Mellitus, Type 2; Double-Blind Method; Erythropoietin; Female; Hematinics; Hemoglobins; Humans; Injections, Subcutaneous; Kidney Failure, Chronic; Male; Middle Aged; Proportional Hazards Models; Risk; Stroke

Numerous preclinical findings and a clinical pilot study suggest that recombinant human erythropoietin (EPO) provides neuroprotection that may be beneficial for the treatment of patients with ischemic stroke. Although EPO has been considered to be a safe and well-tolerated drug over 2 decades, recent studies have identified increased thromboembolic complications and/or mortality risks on EPO administration to patients with cancer or chronic kidney disease. Accordingly, the double-blind, placebo-controlled, randomized German Multicenter EPO Stroke Trial (Phase II/III; ClinicalTrials.gov Identifier: NCT00604630) was designed to evaluate efficacy and safety of EPO in stroke.. This clinical trial enrolled 522 patients with acute ischemic stroke in the middle cerebral artery territory (intent-to-treat population) with 460 patients treated as planned (per-protocol population). Within 6 hours of symptom onset, at 24 and 48 hours, EPO was infused intravenously (40,000 IU each). Systemic thrombolysis with recombinant tissue plasminogen activator was allowed and stratified for.. Unexpectedly, a very high number of patients received recombinant tissue plasminogen activator (63.4%). On analysis of total intent-to-treat and per-protocol populations, neither primary outcome Barthel Index on Day 90 (P=0.45) nor any of the other outcome parameters showed favorable effects of EPO. There was an overall death rate of 16.4% (n=42 of 256) in the EPO and 9.0% (n=24 of 266) in the placebo group (OR, 1.98; 95% CI, 1.16 to 3.38; P=0.01) without any particular mechanism of death unexpected after stroke.. Based on analysis of total intent-to-treat and per-protocol populations only, this is a negative trial that also raises safety concerns, particularly in patients receiving systemic thrombolysis.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Brain Ischemia; Double-Blind Method; Drug Administration Schedule; Drug Interactions; Drug-Related Side Effects and Adverse Reactions; Erythropoietin; Female; Humans; Infarction, Middle Cerebral Artery; Injections, Intravenous; Male; Middle Aged; Mortality; Neuroprotective Agents; Patient Selection; Placebo Effect; Recombinant Proteins; Stroke; Tissue Plasminogen Activator; Treatment Outcome; Young Adult

Anemia is associated with an increased risk of cardiovascular and renal events among patients with type 2 diabetes and chronic kidney disease. Although darbepoetin alfa can effectively increase hemoglobin levels, its effect on clinical outcomes in these patients has not been adequately tested.. In this study involving 4038 patients with diabetes, chronic kidney disease, and anemia, we randomly assigned 2012 patients to darbepoetin alfa to achieve a hemoglobin level of approximately 13 g per deciliter and 2026 patients to placebo, with rescue darbepoetin alfa when the hemoglobin level was less than 9.0 g per deciliter. The primary end points were the composite outcomes of death or a cardiovascular event (nonfatal myocardial infarction, congestive heart failure, stroke, or hospitalization for myocardial ischemia) and of death or end-stage renal disease.. Death or a cardiovascular event occurred in 632 patients assigned to darbepoetin alfa and 602 patients assigned to placebo (hazard ratio for darbepoetin alfa vs. placebo, 1.05; 95% confidence interval [CI], 0.94 to 1.17; P=0.41). Death or end-stage renal disease occurred in 652 patients assigned to darbepoetin alfa and 618 patients assigned to placebo (hazard ratio, 1.06; 95% CI, 0.95 to 1.19; P=0.29). Fatal or nonfatal stroke occurred in 101 patients assigned to darbepoetin alfa and 53 patients assigned to placebo (hazard ratio, 1.92; 95% CI, 1.38 to 2.68; P<0.001). Red-cell transfusions were administered to 297 patients assigned to darbepoetin alfa and 496 patients assigned to placebo (P<0.001). There was only a modest improvement in patient-reported fatigue in the darbepoetin alfa group as compared with the placebo group.. The use of darbepoetin alfa in patients with diabetes, chronic kidney disease, and moderate anemia who were not undergoing dialysis did not reduce the risk of either of the two primary composite outcomes (either death or a cardiovascular event or death or a renal event) and was associated with an increased risk of stroke. For many persons involved in clinical decision making, this risk will outweigh the potential benefits. (ClinicalTrials.gov number, NCT00093015.)

Topics: Aged; Anemia; Cardiovascular Diseases; Darbepoetin alfa; Diabetes Mellitus, Type 2; Double-Blind Method; Erythropoietin; Female; Hematinics; Hemoglobins; Humans; Kaplan-Meier Estimate; Kidney Failure, Chronic; Male; Middle Aged; Neoplasms; Renal Insufficiency, Chronic; Stroke

Anemia, a common complication of chronic kidney disease, usually develops as a consequence of erythropoietin deficiency. Recombinant human erythropoietin (epoetin alfa) is indicated for the correction of anemia associated with this condition. However, the optimal level of hemoglobin correction is not defined.. In this open-label trial, we studied 1432 patients with chronic kidney disease, 715 of whom were randomly assigned to receive a dose of epoetin alfa targeted to achieve a hemoglobin level of 13.5 g per deciliter and 717 of whom were assigned to receive a dose targeted to achieve a level of 11.3 g per deciliter. The median study duration was 16 months. The primary end point was a composite of death, myocardial infarction, hospitalization for congestive heart failure (without renal replacement therapy), and stroke.. A total of 222 composite events occurred: 125 events in the high-hemoglobin group, as compared with 97 events in the low-hemoglobin group (hazard ratio, 1.34; 95% confidence interval, 1.03 to 1.74; P=0.03). There were 65 deaths (29.3%), 101 hospitalizations for congestive heart failure (45.5%), 25 myocardial infarctions (11.3%), and 23 strokes (10.4%). Seven patients (3.2%) were hospitalized for congestive heart failure and myocardial infarction combined, and one patient (0.5%) died after having a stroke. Improvements in the quality of life were similar in the two groups. More patients in the high-hemoglobin group had at least one serious adverse event.. The use of a target hemoglobin level of 13.5 g per deciliter (as compared with 11.3 g per deciliter) was associated with increased risk and no incremental improvement in the quality of life. (ClinicalTrials.gov number, NCT00211120 [ClinicalTrials.gov].).

Topics: Aged; Anemia; Epoetin Alfa; Erythropoietin; Female; Glomerular Filtration Rate; Heart Failure; Hematinics; Hemoglobins; Hospitalization; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Infarction; Recombinant Proteins; Renal Insufficiency, Chronic; Stroke; Survival Analysis

Erythropoietin (EPO) and its receptor play a major role in embryonic brain, are weakly expressed in normal postnatal/adult brain and up-regulated upon metabolic stress. EPO protects neurons from hypoxic/ ischemic injury. The objective of this trial is to study the safety and efficacy of recombinant human EPO (rhEPO) for treatment of ischemic stroke in man.. The trial consisted of a safety part and an efficacy part. In the safety study, 13 patients received rhEPO intravenously (3.3 X 10(4) IU/50 ml/30 min) once daily for the first 3 days after stroke. In the double-blind randomized proof-of-concept trial, 40 patients received either rhEPO or saline. Inclusion criteria were age <80 years, ischemic stroke within the middle cerebral artery territory confirmed by diffusion-weighted MRI, symptom onset <8 hr before drug administration, and deficits on stroke scales. The study endpoints were functional outcome at day 30 (Barthel Index, modified Rankin scale), NIH and Scandinavian stroke scales, evolution of infarct size (sequential MRI evaluation using diffusion-weighted [DWI] and fluid-attenuated inversion recovery sequences [FLAIR]) and the damage marker S100ss.. No safety concerns were identified. Cerebrospinal fluid EPO increased to 60-100 times that of nontreated patients, proving that intravenously administered rhEPO reaches the brain. In the efficacy trial, patients received rhEPO within 5 hr of onset of symptoms (median, range 2:40-7:55). Admission neurologic scores and serum S100beta concentrations were strong predictors ofoutcome. Analysis of covariance controlled for these two variables indicated that rhEPO treatment was associated with an improvement in follow-up and outcome scales. A strong trend for reduction in infarct size in rhEPO patients as compared to controls was observed by MRI.. Intravenous high-dose rhEPO is well tolerated in acute ischemic stroke and associated with an improvement in clinical outcome at 1 month. A larger scale clinical trial is warranted.

Topics: Blood Platelets; Double-Blind Method; Erythrocytes; Erythropoietin; Hematocrit; Humans; Infusions, Intravenous; Stroke; Time Factors

Inflammasomes are known to contribute to brain damage after acute ischemic stroke (AIS). TAK1 is predominantly expressed in microglial cells and can regulate the NLRP3 inflammasome, but its impact on other inflammasomes including NLRC4 and AIM2 after AIS remains elusive. EPO has been shown to reduce NLRP3 protein levels in different disease models. Whether EPO-mediated neuroprotection after AIS is conveyed via an EPO/TAK1/inflammasome axis in microglia remains to be clarified. Subjecting mice deficient for TAK1 in microglia/macrophages (Mi/MΦ) to AIS revealed a significant reduction in infarct sizes and neurological impairments compared to the corresponding controls. Post-ischemic increased activation of TAK1, NLRP3, NLRC4, and AIM2 inflammasomes including their associated downstream cascades were markedly reduced upon deletion of Mi/MΦ TAK1. EPO administration improved clinical outcomes and dampened stroke-induced activation of TAK1 and inflammasome cascades, which was not evident after the deletion of Mi/MΦ TAK1. Pharmacological inhibition of NLRP3 in microglial BV-2 cells did not influence post-OGD IL-1β levels, but increased NLRC4 and AIM2 protein levels, suggesting compensatory activities among inflammasomes. Overall, we provide evidence that Mi/MΦ TAK1 regulates the expression and activation of the NLRP3, NLRC4, AIM2 inflammasomes. Furthermore, EPO mitigated stroke-induced activation of TAK1 and inflammasomes, indicating that EPO conveyed neuroprotection might be mediated via an EPO/TAK1/inflammasome axis.

Topics: Animals; Apoptosis Regulatory Proteins; Calcium-Binding Proteins; DNA-Binding Proteins; Erythropoietin; Inflammasomes; Interleukin-1beta; Ischemic Stroke; Macrophages; MAP Kinase Kinase Kinases; Mice; Mice, Inbred C57BL; Microglia; NLR Family, Pyrin Domain-Containing 3 Protein; Stroke

In 2011, the Centers for Medicare & Medicaid Services implemented bundling of all services for patients receiving dialysis, including erythropoietin-stimulating agents use, and the Food and Drug Administration recommended conservative erythropoietin-stimulating agent dosing.. This retrospective cohort study investigated anemia care and clinical outcomes before and after the Centers for Medicare & Medicaid Services bundled payment and the revised Food and Drug Administration-recommended erythropoietin-stimulating agent labeling for Medicare-insured adults receiving hemodialysis using data from the United States Renal Data System from January 1, 2006 to December 31, 2016. Clinical outcomes included major adverse cardiovascular event (stroke, acute myocardial infarction, and all-cause mortality), cardiovascular mortality, and heart failure. Measurements were compared between prepolicy (2006-2010) and postpolicy (2012-2016) implementation using interrupted time series and Cox proportional hazards regression models.. The Medicare reimbursement policy and Food and Drug Administration-recommended erythropoietin-stimulating agent dosing changes were associated with lower erythropoietin-stimulating agent use and lower hemoglobin levels. These changes in anemia care were associated with lower risks of major adverse cardiovascular event, stroke, mortality, and heart failure but higher risk of acute myocardial infarction among adults receiving hemodialysis.

Topics: Adult; Aged; Anemia; Epoetin Alfa; Erythropoietin; Heart Failure; Hematinics; Hemoglobins; Humans; Kidney Failure, Chronic; Medicare; Myocardial Infarction; Policy; Renal Dialysis; Retrospective Studies; Stroke; United States

Spinal strokes may be associated with tremendous spinal cord injury. Erythropoietin (EPO) improves the neurological outcome of animals after spinal cord ischemia (SCI) and its effects on ischemia-induced endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) are considered possible molecular mechanisms. Furthermore, sphingosin-1-phosphate (S1P) is suggested to correlate with SCI. In this study, the effect of recombinant human EPO (rhEPO) and carbamylated EPO (cEPO-Fc) on the outcome of mice after SCI and a prognostic value of S1P were investigated. SCI was induced in 12-month-old male mice by thoracic aortal cross-clamping after administration of rhEPO, cEPO-Fc, or a control. The locomotory behavior of mice was evaluated by the Basso mouse scale and S1P serum levels were measured by liquid chromatography-tandem mass spectrometry. The spinal cord was examined histologically and the expressions of key UPR proteins (ATF6, PERK, and IRE1a, caspase-12) were analyzed utilizing immunohistochemistry and real-time quantitative polymerase chain reaction. RhEPO and cEPO-Fc significantly improved outcomes after SCI. The expression of caspase-12 significantly increased in the control group within the first 24 h of reperfusion. Animals with better locomotory behavior had significantly higher serum levels of S1P. Our data indicate that rhEPO and cEPO-Fc have protective effects on the clinical outcome and neuronal tissue of mice after SCI and that the ER is involved in the molecular mechanisms. Moreover, serum S1P may predict the severity of impairment after SCI.

Topics: Animals; Caspase 12; Epoetin Alfa; Erythropoietin; Humans; Infant; Lysophospholipids; Male; Mice; Neuroprotective Agents; Recombinant Proteins; Sphingosine; Spinal Cord Injuries; Spinal Cord Ischemia; Stroke

Although electroacupuncture (EA) has been shown to be effective in the treatment of stroke, its mechanisms of action remain undefined. This study explored the therapeutic effects of EA in rats with cerebral ischemia-reperfusion injury (CIRI) and evaluated its possible mechanisms in promoting angiogenesis. To evaluate the effect of EA, we used 2, 3, 5-Triphenyl-2H-Tetrazolium Chloride (TTC) staining and behavior score to calculate the cerebral infarct volume and neurological deficit score after CIRI. Western blot (WB) analysis was employed to evaluate the expression of cluster of differentiation 34 (CD34), erythropoietin (EPO), vascular endothelial growth factor (VEGF) and phospho-Src (p-Src) in the brain of the rats with CIRI. On the other hand, we established an oxygen-glucose deprivation/reoxygenation (OGD/R) injury model using brain microvascular endothelial cells (BMECs), and analyzed cell viability and expression of VEGF or p-Src using cell counting kit-8 (CCK-8) and WB, respectively. Our data showed that EA at the GV26 acupoint could significantly promote the expression of CD34, EPO, VEGF and p-Src in CIRI rats. Our CCK-8 results demonstrated that intervention with recombinant EPO and VEGF proteins remarkably improved the viability of BMECs after OGD/R, while a Src inhibitor, PP1, reversed this phenotype. The WB results showed that the recombinant EPO protein increased the expression of VEGF and p-Src, which was significantly inhibited by PP1. Taken together, our findings showed that EA at the GV26 acupoint can significantly attenuate ischemic injury after stroke and promote angiogenesis via activation of EPO-mediated Src and VEGF signaling pathways. Besides, the upregulation of VEGF may also be associated with the activation of Src by EPO.

Topics: Animals; Chlorides; Electroacupuncture; Endothelial Cells; Erythropoietin; Glucose; Ischemia; Oxygen; Rats; Reperfusion Injury; Signal Transduction; Stroke; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors

Background Targeting higher hemoglobin levels with erythropoietin to treat anemia in patients with chronic kidney disease is associated with increased cardiovascular risk, including that of stroke. The risks of the subtypes of stroke, ischemic, hemorrhagic, and unspecified, following the administration of erythropoietin in patients with end-stage renal disease receiving hemodialysis remain unclear. Methods and results Overall, 12 948 adult patients with end-stage renal disease treated during 1999 to 2010 who had undergone hemodialysis were included. The study end points were the incidences of stroke and its subtypes. We used Cox proportional hazards regression models to estimate hazard ratios (HRs) of stroke and its subtypes in erythropoietin recipients compared with nonrecipients. Patients in the erythropoietin cohort did not have an increased risk of stroke compared with those in the nonerythropoietin cohort (adjusted HR, 1.03; 95% CI, 0.92-1.15). Compared with patients in the nonerythropoietin cohort, the risks of ischemic, hemorrhagic, or unspecified stroke were not higher in patients in the erythropoietin cohort (adjusted HRs, 1.08 [95% CI, 0.93-1.26], 0.96 [95% CI, 0.78-1.18], and 1.03 [95% CI, 0.80-1.32], respectively). Increased risks of stroke and its subtypes were not observed with even large annual defined daily doses of erythropoietin (>201). Conclusions Erythropoietin in patients receiving hemodialysis is not associated with increased risk of stroke or any of its subtypes.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Dose-Response Relationship, Drug; Erythropoietin; Female; Humans; Kidney Failure, Chronic; Male; Middle Aged; Proportional Hazards Models; Renal Dialysis; Retrospective Studies; Stroke; Taiwan; Young Adult

Therapeutic delivery to the brain is limited by the blood-brain barrier and is exacerbated by off-target effects associated with systemic delivery, thereby precluding many potential therapies from even being tested. Given the systemic side effects of cyclosporine and erythropoietin, systemic administration would be precluded in the context of stroke, leaving only the possibility of local delivery. We wondered if direct delivery to the brain would allow new reparative therapeutics, such as these, to be identified for stroke. Using a rodent model of stroke, we employed an injectable drug delivery hydrogel strategy to circumvent the blood-brain barrier and thereby achieved, for the first time, local and sustained co-release to the brain of cyclosporine and erythropoietin. Both drugs diffused to the sub-cortical neural stem and progenitor cell (NSPC) niche and were present in the brain for at least 32 days post-stroke. Each drug had a different outcome on brain tissue: cyclosporine increased plasticity in the striatum while erythropoietin stimulated endogenous NSPCs. Only their co-delivery, but not either drug alone, accelerated functional recovery and improved tissue repair. This platform opens avenues for hitherto untested therapeutic combinations to promote regeneration and repair after stroke.

Topics: Animals; Brain; Cyclosporine; Erythropoietin; Hydrogels; Rats; Stroke

Previously study has proved the non-erythropoietic mutant erythropoietin (MEPO) exerted neuroprotective effects against ischemic cerebral injury, with an efficacy similar to that of wild-type EPO. This study investigates its effects on neurogenesis, angiogenesis, and gliogenesis in cerebral ischemic mice. Male C57BL/6 mice were subjected to middle cerebral artery occlusion (MCAO) and reperfusion. EPO (5000 U/kg), MEPO (5000 U/kg) or equal volume of normal saline was injected intraperitoneally. Neurological function was evaluated by Rota-rod test, Neurological severity scores (NSS) and Adhesive removal test. After ischemia and reperfusion (I/R), the survival rate, brain tissue loss, neurogenesis, angiogenesis and gliogenesis were detected by Nissl staining, Immunofluorescence and Western blot, respectively. The results shown that MEPO significantly increased survival rate, reduced brain tissue loss, and improved neurological function after MCAO (P < 0.05). Furthermore, MEPO obviously enhanced the proliferation of neuronal precursors (DCX) and promoted its differentiation into mature neurons (NeuN) (P < 0.05). In addition, compared to normal saline treatment mice, MEPO increased the number of BrdU-positive cells in the cerebral vasculature (P < 0.05). Whereas, MEPO treatment also reduced the numbers of newly generated astrocytes (GFAP) and microglia (Iba1) (P < 0.05). Among all the tests in this study, there was no significant difference between EPO group and MEPO group. Taken together, MEPO promoted the regeneration of neurons and blood vessels in peripheral area of infarction, and suppressed the gliogenesis, thus promoting neurogenesis, improving neurological function and survival rate. Our findings suggest that the MEPO may be a therapeutic drug for ischemic stroke intervention.

Topics: Animals; Brain Ischemia; Cell Proliferation; Doublecortin Protein; Erythropoietin; Male; Mice; Mice, Inbred C57BL; Mutation; Neovascularization, Physiologic; Neurogenesis; Neuroglia; Neuroprotection; Stroke

Erythropoietin (EPO) can enhance neurogenesis and fibroblasts can secrete growth factors; together, they may benefit ischemic stroke. We transplanted EPO-producing fibroblasts into the rodent infarcted brain to test their effect on neurogenesis and functional recovery.. The MCAO rats with EPO/EGFP/3T3 treatment showed high EPO expression in the infarcted brain for at least 1 week. The concentration of brain-derived neurotrophic factor was higher in both hemispheres of MCAO rats with either EGFP/3T3 or EPO/EGFP/3T3 treatment at 14 days poststroke compared with untreated MCAO rats. The number of Ki-67-, nestin-, or doublecortin-immunoreactive cells in bilateral subventricular zones was higher in EPO/EGFP/3T3-treated MCAO rats than it was in untreated MCAO control animals, indicating the enhancement of neurogenesis after EPO/EGFP/3T3 treatment. Notably, post-MCAO EPO/EGFP/3T3 treatment significantly reduced infarct size and improved functional recovery.. The intracerebral transplantation of EPO-producing fibroblasts benefited an ischemic stroke model probably via the enhancement of neurogenesis.

Topics: Animals; Brain Ischemia; Cell- and Tissue-Based Therapy; Disease Models, Animal; Doublecortin Protein; Erythropoietin; Fibroblasts; Male; Neurogenesis; Rats; Recovery of Function; Stroke; Treatment Outcome

Stroke is a major cause of adult mortality and morbidity worldwide. However, the treatment of stroke using the vast majority of possible drug candidates, including erythropoietin (EPO), remains problematic because of the presence of the blood-brain barrier (BBB), resulting in scarce penetration onto the brain. To overcome this, we synthesized a novel EPO delivery system, namely the cholic acid-coated poly lactic-co-glycolic acid (PLGA) nanoparticles loaded with EPO (EPO-CA-NPs), with the aim of enabling efficient penetration of EPO-CA-NPs across the BBB. The therapeutic efficacy of EPO-CA-NPs on an animal model of stroke was compared with that of EPO. The experimental stroke model was produced by subjecting rats to the middle carotid artery occlusion and reperfusion (MCAO/R) technique. The results indicated that EPO-CA-NPs reduced the extent of the infarct volume and cellular apoptosis to a greater extent than EPO alone at postoperative day (POD) 1. Furthermore, EPO-CA-NPs showed better performance on sensorimotor functions than EPO alone at POD 1, 3, 5, and 7. Taken together, EPO-CA-NPs, a newly synthesized brain-targeted EPO-delivery system, has stronger therapeutic effects on stroke than EPO alone, by enabling efficient EPO delivery into the brain.

Topics: Animals; Cholic Acid; Drug Carriers; Erythropoietin; Glycolates; Lactic Acid; Nanoparticles; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Rats; Stroke

Erythropoietin (EPO) has been well known as a hematopoietic cytokine over the past decades. However, recent reports have demonstrated that EPO plays a neuroprotective role in the central nervous system, and EPO has been considered as a therapeutic target in neurodegenerative diseases such as ischemic stroke. Despite the neuroprotective effect of EPO, clinical trials have shown its unexpected side effects, including undesirable proliferative effects such as erythropoiesis and tumor growth. Therefore, the development of EPO analogs that would confer neuroprotection without adverse effects has been attempted. In this study, we examined the potential of a novel EPO-based short peptide, MK-X, as a novel drug for stroke treatment in comparison with EPO. We found that MK-X administration with reperfusion dramatically reduced brain injury in an in vivo mouse model of ischemic stroke induced by middle cerebral artery occlusion, whereas EPO had little effect. Similar to EPO, MK-X efficiently ameliorated mitochondrial dysfunction followed by neuronal death caused by glutamate-induced oxidative stress in cultured neurons. Consistent with this effect, MK-X significantly decreased caspase-3 cleavage and nuclear translocation of apoptosis-inducing factor induced by glutamate. MK-X completely mimicked the effect of EPO on multiple activation of JAK2 and its downstream PI3K/AKT and ERK1/2 signaling pathways, and this signaling process was involved in the neuroprotective effect of MK-X. Furthermore, MK-X and EPO induced similar changes in the gene expression patterns under glutamate-induced excitotoxicity. Interestingly, the most significant difference between MK-X and EPO was that MK-X better penetrated into the brain across the brain-blood barrier than did EPO. In conclusion, we suggest that MK-X might be used as a novel drug for protection from brain injury caused by ischemic stroke, which penetrates into the brain faster in comparison with EPO, even though MK-X and EPO have similar protective effects against excitotoxicity.

Topics: Animals; Blood-Brain Barrier; Brain Ischemia; Caspase 3; Cell Death; Cerebral Cortex; Cerebrovascular Disorders; Embryo, Mammalian; Erythropoietin; Gene Expression Regulation; Glutamic Acid; Janus Kinase 2; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Middle Cerebral Artery; Mitochondria; Neurons; Neuroprotective Agents; Peptides; Permeability; Phosphatidylinositol 3-Kinases; Primary Cell Culture; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Stroke

There is interest in pharmacologic preconditioning for end-organ protection by targeting the HIF system. This can be accomplished by inhibition of prolyl 4-hydroxylase (PHD). GSK360A is an orally active PHD inhibitor that has been previously shown to protect the failing heart. We hypothesized that PHD inhibition can also protect the brain from injuries and resulting behavioral deficits that can occur as a result of surgery. Thus, our goal was to investigate the effect of pre-stroke surgery brain protection using a verified GSK360A PHD inhibition paradigm on post-stroke surgery outcomes. Vehicle or an established protective dose (30 mg/kg, p.o.) of GSK360A was administered to male Sprague-Dawley rats. Initially, GSK360A pharmacokinetics and organ distribution were determined, and then PHD-HIF pharmacodynamic markers were measured (i.e., to validate the pharmacological effects of the GSK360A administration regimen). Results obtained using this validated PHD dose-regimen indicated significant improvement by GSK360A (30mg/kg); administered at 18 and 5 hours prior to transient middle cerebral artery occlusion (stroke). GSK360A exposure and plasma, kidney and brain HIF-PHD pharmacodynamics endpoints (e.g., erythropoietin; EPO and Vascular Endothelial Growth Factor; VEGF) were measured. GSK360A provided rapid exposure in plasma (7734 ng/ml), kidney (45-52% of plasma level) and brain (1-4% of plasma level), and increased kidney EPO mRNA (80-fold) and brain VEGF mRNA (2-fold). We also observed that GSK360A increased plasma EPO (300-fold) and VEGF (2-fold). Further assessments indicated that GSK360A reduced post-stroke surgery neurological deficits (47-64%), cognitive dysfunction (60-75%) and brain infarction (30%) 4 weeks later. Thus, PHD inhibition using GSK360A pretreatment produced long-term post-stroke brain protection and improved behavioral functioning. These data support PHD inhibition, specifically by GSK360A, as a potential strategy for pre-surgical use to reduce brain injury and functional decline due to surgery-related cerebral injury.

Topics: Administration, Oral; Animals; Behavior, Animal; Brain; Brain Injuries; Cognition Disorders; Erythropoietin; Glycine; Hypoxia-Inducible Factor 1, alpha Subunit; Infarction, Middle Cerebral Artery; Male; Motor Activity; Organ Specificity; Prolyl Hydroxylases; Prolyl-Hydroxylase Inhibitors; Quinolones; Rats, Sprague-Dawley; RNA, Messenger; Sensation; Stroke; Vascular Endothelial Growth Factor A

The European Medicines Agency recommends limiting the hemoglobin (Hb) concentration to 10 to 12 g/dL in adults with chronic kidney disease (CKD) receiving erythropoiesis-stimulating agents such as epoetin theta. This postauthorization study assessed the incidence and intensity of cardiovascular events, including ischemic stroke, in patients receiving epoetin theta for anemia associated with CKD. A secondary end point was adverse drug reactions, including pure red cell aplasia.. In this prospective, noninterventional, multinational cohort study, consecutive patients with advanced or end-stage renal disease and receiving epoetin theta were followed up for 6 months. Data on reportable adverse events (RAEs) (cardiac disorders, cardiac failure, myocardial infarction, and ischemic stroke and respective subterms), epoetin theta dosage, and Hb concentrations were collected. A post hoc exploratory analysis assessed the incidences of RAEs according to tertiles for individual mean Hb concentration (≤10.7, >10.7-11.47, and >11.47 g/dL for low, intermediate, and high, respectively) and mean weekly epoetin theta dosage (≤62, >62-125, and >125 IU/kg/wk for low, intermediate, and high).. Data from 1039 patients were included (577 men, 462 women; mean age, 68.7 years). A total of 101 RAEs were documented in 89 patients (8.6%), for an event rate of 0.1985/person-year. Sixty-four patients (6.1%) died; none of the deaths was considered related to epoetin theta use. The incidence of RAEs was lowest at intermediate Hb concentrations (6.2%) compared with low (11.3%) and high (7.8%) Hb concentrations. The incidence of ischemic stroke was 1.5% at high Hb concentrations versus 0.6% at both the low and intermediate Hb concentrations. The incidence of any RAE was greater in the high-dose group (10.1%) than in the intermediate-dose (8.0%) and low-dose (7.6%) groups. The risk for any cardiovascular RAE or ischemic stroke was greatest in the high-dose/high-Hb group (13.3%), followed by high dose/low Hb (12.6%) and low dose/low Hb (12.1%). The risks for RAEs were lowest at high dose/intermediate Hb (3.8%) and low dose/intermediate Hb (5.3%). The event rate of adverse drug reactions other than the predefined RAEs was 0.0161/person-year. No cases of pure red cell aplasia were reported.. The findings from the present study suggest that, for maintaining the optimal target Hb concentration (10-12 g/dL according to the current summary of product characteristics for epoetin theta; 10-11.5 g/dL according to the current guideline from Kidney Disease Improving Global Outcomes) in anemic adults with CKD, the lowest approved, effective dose epoetin theta should be used.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anemia; Cohort Studies; Erythropoietin; Female; Heart Failure; Hematinics; Humans; Kidney Failure, Chronic; Male; Middle Aged; Myocardial Infarction; Prospective Studies; Red-Cell Aplasia, Pure; Renal Insufficiency, Chronic; Stroke; Young Adult

In patients with heart failure (HF), serum erythropoietin (EPO) levels are elevated and associated with disease severity and outcome. Whether endogenous EPO levels are prospectively associated with the development of HF or cardiovascular events in the general population is unknown.. Serum EPO levels were measured at baseline in 6686 subjects enrolled in the Prevention of REnal and Vascular ENd-stage Disease (PREVEND) study. Mean age (±SD) was 53 ± 12 years, 49.8% were male, and the median (interquartile range) EPO level was 7.7 (5.9-10.2) IU/L. During a median follow-up of 8.3 (7.7-8.8) years, 209 (3.1%) subjects were newly diagnosed with HF, 97 (1.5%) died of a cardiovascular cause, and 386 (6.0%) subjects had a non-fatal cardiovascular event (277 cardiac events and 93 strokes). Each doubling of EPO level was multivariably associated with new-onset HF [hazard ratio (HR) 1.32, 95% confidence interval (CI) 1.03-1.69, P = 0.031]. EPO levels showed interaction with urinary albumin excretion (P = 0.006) and were only associated with HF in subjects with albuminuria (HR 1.51, 95% CI 1.13-2.03, P = 0.005). There was an independent association of EPO levels with stroke in women (HR 1.82, 95% CI 1.24-2.65, P = 0.002), but not in men. No association was observed for EPO levels with other cardiovascular events or cardiovascular mortality.. High serum EPO levels are independently associated with an increased risk of new-onset HF in subjects with albuminuria. More research into the pathophysiological mechanisms linking EPO levels to HF is needed to understand this association.

Topics: Adult; Aged; Albuminuria; Cardiovascular Diseases; Erythropoietin; Female; Heart Failure; Humans; Male; Middle Aged; Multivariate Analysis; Myocardial Infarction; Myocardial Ischemia; Myocardial Revascularization; Netherlands; Prognosis; Proportional Hazards Models; Sex Factors; Stroke

Stroke is a major cause of neonatal morbidity, often with delayed diagnosis and with no accepted therapeutic options. The purpose of this study is to investigate the efficacy of delayed initiation of multiple dose erythropoietin (EPO) therapy in improving histological and behavioral outcomes after early transient ischemic stroke.. 32 postnatal day 10 (P10) Sprague-Dawley rats underwent sham surgery or transient middle cerebral artery occlusion (tMCAO) for 3h, resulting in injury involving the striatum and parieto-temporal cortex. EPO (1000U/kg per dose×3 doses) or vehicle was administered intraperitoneally starting one week after tMCAO (at P17, P20, and P23). At four weeks after tMCAO, sensorimotor function was assessed in these four groups (6 vehicle-sham, 6 EPO-sham, 10 vehicle-tMCAO and 10 EPO-tMCAO) with forepaw preference in cylinder rearing trials. Brains were then harvested for hemispheric volume and Western blot analysis.. EPO-tMCAO animals had significant improvement in forepaw symmetry in cylinder rearing trials compared to vehicle-tMCAO animals, and did not differ from sham animals. There was also significant preservation of hemispheric brain volume in EPO-tMCAO compared to vehicle-tMCAO animals. No differences in ongoing cell death at P17 or P24 were noted by spectrin cleavage in either EPO-tMCAO or vehicle-tMCAO groups.. These results suggest that delayed EPO therapy improves both behavioral and histological outcomes at one month following transient neonatal stroke, and may provide a late treatment alternative for early brain injury.

Topics: Animals; Animals, Newborn; Brain; Brain Injuries; Cell Death; Erythropoietin; Hypoxia-Ischemia, Brain; Infarction, Middle Cerebral Artery; Neurons; Rats, Sprague-Dawley; Stroke

Stroke is associated with neuroinflammation, neuronal loss and blood-brain barrier (BBB) breakdown. Thus far, recombinant tissue-type plasminogen activator (rtPA), the only approved treatment for acute ischemic stroke, increases the risk of intracerebral hemorrhage and is poorly efficient in disaggregating platelet-rich thrombi. Therefore, the development of safer and more efficient therapies is highly awaited. Encouraging neuroprotective effects were reported in mouse models of ischemic stroke following administration of erythropoietin (EPO). However, previous preclinical studies did not investigate the effects of EPO in focal ischemic stroke induced by a platelet-rich thrombus and did not consider the implication of age. Here, we performed middle cerebral artery occlusion by inducing platelet-rich thrombus formation in chimeric 5- (i.e. young) and 20- (i.e. aged) months old C57BL/6 mice, in which hematopoietic stem cells carried the green fluorescent protein (GFP)-tag. Recombinant human EPO (rhEPO) was administered 24 hours post-occlusion and blood-circulating monocyte populations were studied by flow cytometry 3 hours post-rhEPO administration. Twenty-four hours following rhEPO treatment, neuronal loss and BBB integrity were assessed by quantification of Fluoro-Jade B (FJB)-positive cells and extravasated serum immunoglobulins G (IgG), respectively. Neuroinflammation was determined by quantifying infiltration of GFP-positive bone marrow-derived cells (BMDC) and recruitment of microglial cells into brain parenchyma, along with monocyte chemotactic protein-1 (MCP-1) brain protein levels. Here, rhEPO anti-inflammatory properties rescued ischemic injury by reducing neuronal loss and BBB breakdown in young animals, but not in aged littermates. Such age-dependent effects of rhEPO must therefore be taken into consideration in future studies aiming to develop new therapies for ischemic stroke.

Topics: Age Factors; Animals; Blood-Brain Barrier; Brain; Brain Ischemia; Chemokine CCL2; Disease Models, Animal; Erythropoietin; Flow Cytometry; Green Fluorescent Proteins; Humans; Inflammation; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Middle Cerebral Artery; Neuroprotective Agents; Recombinant Proteins; Stroke; Thrombosis

To reduce side effects due to non-specific expression, the heme oxygenase-1 (HO-1) gene under control of a hypoxia-inducible erythropoietin (Epo) enhancer (pEpo-SV-HO-1) was developed for site-specific gene therapy of ischemic stroke.. pEpo-SV-HO-1 was constructed by insertion of the Epo enhancer into pSV-HO-1. Dexamethasone-conjugated polyamidoamine (PAMAM-Dexa) was used as a gene carrier. In vitro transfection assays were performed in the Neuro2A cells. In vivo efficacy of pEpo-SV-HO-1 was evaluated in the transient middle cerebral artery occlusion (MCAO) model.. In vitro transfection assay with the PAMAM-Dexa/pEpo-SV-HO-1 complex showed that pEpo-SV-HO-1 had higher HO-1 gene expression than pSV-HO-1 under hypoxia. In addition, pEpo-SV-HO-1 reduced the level of apoptosis more efficiently than pSV-HO-1 in Neuro2A cells under hypoxia. For in vivo evaluation, the PAMAM-Dexa/pEpo-SV-HO-1 complex was injected into the ischemic brain of the transient MCAO model. pEpo-SV-HO-1 increased HO-1 expression and reduced the number of apoptotic cells in the ischemic brain, compared with the pSV-HO-1 injection group. As a result, the infarct volume was more efficiently decreased by pEpo-SV-HO-1 than by pSV-HO-1.. pEpo-SV-HO-1 induced HO-1 gene expression and therapeutic effect in the ischemic brain. Therefore, pEpo-SV-HO-1 may be useful for site-specific gene therapy of ischemic stroke.

Topics: Animals; Brain; Cell Line, Tumor; Dexamethasone; Disease Models, Animal; Erythropoietin; Gene Transfer Techniques; Genetic Therapy; Heme Oxygenase-1; Hypoxia; Infarction, Middle Cerebral Artery; Male; Polyamines; Rats; Rats, Sprague-Dawley; Stroke; Transfection

Using the model of bilateral photothrombosis of the blood vessels in the prefrontal cortex we have shown that new hybrid proteins derived from recombinant human erythropoietin, carbamylated EPO-Fc and EPO-TR fusion proteins, injected intraperitoneally 1 h after ischemic injury contribute to restoration of passive avoidance response formed before photothrombotic injury and reduction in the volume of the ischemic focus. These data attest to nootropic and neuroprotective activities of these hybrid proteins. Carbamylated glycopeptide derivative ЕPO-TR exhibited prolonged neuroprotective properties.

Topics: Animals; Cerebral Cortex; Erythropoietin; Humans; Male; Neuroprotective Agents; Prefrontal Cortex; Rats; Stroke

Adequately powered studies directly comparing hard clinical outcomes of darbepoetin alfa (DPO) versus epoetin alfa (EPO) in patients undergoing dialysis are lacking.. Observational, registry-based, retrospective cohort study; we mimicked a cluster-randomized trial by comparing mortality and cardiovascular events in US patients initiating hemodialysis therapy in facilities (almost) exclusively using DPO versus EPO.. Nonchain US hemodialysis facilities; each facility switching from EPO to DPO (2003-2010) was matched for location, profit status, and facility type with one EPO facility. Patients subsequently initiating hemodialysis therapy in these facilities were assigned their facility-level exposure.. DPO versus EPO.. All-cause mortality, cardiovascular mortality; composite of cardiovascular death, nonfatal myocardial infarction (MI), and nonfatal stroke.. Unadjusted and adjusted HRs from Cox proportional hazards regression models.. Of 508 dialysis facilities that switched to DPO, 492 were matched with a similar EPO facility; 19,932 (DPO: 9,465 [47.5%]; EPO: 10,467 [52.5%]) incident hemodialysis patients were followed up for 21,918 person-years during which 5,550 deaths occurred. Almost all baseline characteristics were tightly balanced. The demographics-adjusted mortality HR for DPO (vs EPO) was 1.06 (95% CI, 1.00-1.13) and was materially unchanged after adjustment for all other baseline characteristics (HR, 1.05; 95% CI, 0.99-1.12). Cardiovascular mortality did not differ between groups (HR, 1.05; 95% CI, 0.94-1.16). Nonfatal outcomes were evaluated among 9,455 patients with fee-for-service Medicare: 4,542 (48.0%) in DPO and 4,913 (52.0%) in EPO facilities. During 10,457 and 10,363 person-years, 248 and 372 events were recorded, respectively, for strokes and MIs. We found no differences in adjusted stroke or MI rates or their composite with cardiovascular death (HR, 1.10; 95% CI, 0.96-1.25).. Nonrandom treatment assignment, potential residual confounding.. In incident hemodialysis patients, mortality and cardiovascular event rates did not differ between patients treated at facilities predominantly using DPO versus EPO.

Topics: Aged; Ambulatory Care Facilities; Anemia; Cardiovascular Diseases; Cause of Death; Comorbidity; Darbepoetin alfa; Epoetin Alfa; Erythropoietin; Female; Hematinics; Hemodialysis Units, Hospital; Humans; Kidney Failure, Chronic; Male; Middle Aged; Myocardial Infarction; Proportional Hazards Models; Recombinant Proteins; Registries; Renal Dialysis; Renal Insufficiency, Chronic; Retrospective Studies; Stroke; Treatment Outcome; United States

To perform a feasibility and safety study with recombinant human erythropoietin (rhEPO) in neonates with perinatal arterial ischemic stroke.. Neonates with a magnetic resonance imaging-confirmed perinatal arterial ischemic stroke (n = 21) were treated with 1000 IU/kg rhEPO immediately after diagnosis and at 24 and 48 hours after the first dose. Repeat magnetic resonance imaging was performed when the patients were 3 months of age. Coagulation and hematologic variables (red blood cells, white blood cells, platelet counts) were performed in the first week after initiation of treatment. We also compared 10 patients who were treated with rhEPO with 10 historic infants with perinatal arterial ischemic stroke matched for the involved arterial branch to investigate whether rhEPO reduces the residual size of the infarction and subsequent brain growth between first and second scan.. Seizures were a first symptom in 20 of 21 neonates. Heart rate, blood pressure, and coagulation function were in the normal range, as were red blood cells, white blood cells, and platelet counts. In a subgroup of 10 rhEPO-treated neonates, no differences were detected in residual infarction volumes or neurodevelopmental outcome compared with their historical nontreated counterparts.. rhEPO in neonates with perinatal arterial ischemic stroke had no adverse effects on red blood cells, white blood cells, platelets counts, or coagulation. rhEPO, 3000 IU/kg in total, given during a 3-day period, appears to be a safe therapy. The beneficial effects remains to be demonstrated in a larger, randomized, double-blind, placebo-controlled trial.

Topics: Blood Cell Count; Brain Ischemia; Cerebral Palsy; Erythropoietin; Feasibility Studies; Female; Hematocrit; Hemoglobins; Humans; Infant, Newborn; Magnetic Resonance Imaging; Male; Matched-Pair Analysis; Neuroprotective Agents; Recombinant Proteins; Seizures; Stroke

Rehabilitation is the only treatment option for chronic stroke deficits, but unfortunately, it often provides incomplete recovery. In this study, a novel combination of growth factor administration and rehabilitation therapy was used to facilitate functional recovery in a rat model of cortical stroke.. Ischemia was induced via injection of endothelin-1 into the sensorimotor cortex. This was followed by either a 2-week infusion of epidermal growth factor and erythropoietin or artificial cerebrospinal fluid into the ipsilateral lateral ventricle. Two weeks after ischemia, animals began an 8-week enriched rehabilitation program. Functional recovery was assessed after ischemia using the Montoya staircase-reaching task, beam-traversing, and cylinder test of forelimb asymmetry.. The combination of growth factor infusion and rehabilitation led to a significant acceleration in recovery in the staircase task. When compared with controls, animals receiving the combination treatment attained significant recovery of function at 4 weeks after stroke, whereas those receiving rehabilitation alone did not recover until 10 weeks. Significant recovery was also observed on the beam-traversing and cylinder tasks.. Combining behavioral rehabilitation with growth factor infusion accelerates motor recovery. These data suggest a promising new avenue of combination therapies that may have the potential to reduce the rehabilitation time necessary to recover from sensorimotor deficits arising from stroke.

Topics: Animals; Chronic Disease; Disease Models, Animal; Endothelin-1; Epidermal Growth Factor; Erythropoietin; Male; Motor Activity; Rats; Rats, Sprague-Dawley; Stroke; Stroke Rehabilitation

Topics: Adrenal Cortex Hormones; Anticholesteremic Agents; Authorship; Bias; Conflict of Interest; Controlled Clinical Trials as Topic; Drug Administration Schedule; Drug Industry; Early Termination of Clinical Trials; Erythropoietin; Evidence-Based Medicine; Fear; Fibrinolytic Agents; Guideline Adherence; Humans; Malpractice; National Institutes of Health (U.S.); Periodicals as Topic; Practice Guidelines as Topic; Societies, Medical; Spinal Cord Injuries; Standard of Care; Stroke; Tissue Plasminogen Activator; Trust; United States

In a setting with two concurrent treatments, inverse-probability-of-treatment weights can be used to estimate the joint treatment effects or the marginal effect of one treatment while taking the other to be a confounder. We explore these two approaches in a study of intravenous iron use in hemodialysis patients treated concurrently with epoetin alfa (EPO).. We linked US Renal Data System data with electronic health records (2004-2008) from a large dialysis provider. Using a retrospective cohort design with 776,203 records from 117,050 regular hemodialysis patients, we examined a composite outcome: mortality, myocardial infarction, or stroke.. With EPO as a joint treatment, inverse-probability-of-treatment weights were unstable, confidence intervals for treatment effects were wide, covariate balance was unsatisfactory, and the treatment and outcome models were sensitive to omission of the baseline EPO covariate. By handling EPO exposure as a confounder instead of a joint treatment, we derived stable weights and balanced treatment groups on measured covariates.. In settings with concurrent treatments, if only one treatment is of interest, then including the other in the treatment model as a confounder may result in more stable treatment effect estimates. Otherwise, extreme weights may necessitate additional analysis steps.

Topics: Anemia; Confounding Factors, Epidemiologic; Drug Therapy, Combination; Epidemiologic Methods; Epoetin Alfa; Erythropoietin; Ferric Compounds; Hematinics; Humans; Kidney Failure, Chronic; Medicare; Myocardial Infarction; Outcome Assessment, Health Care; Recombinant Proteins; Renal Dialysis; Stroke; Transferrin; United States

Topics: Age of Onset; Altitude; Erythropoietin; Humans; Risk Factors; Stroke

Stroke is a leading cause of disability with no effective regenerative treatment. One promising strategy for achieving tissue repair involves the stimulation of endogenous neural stem/progenitor cells through sequential delivery of epidermal growth factor (EGF) followed by erythropoietin (EPO). Yet currently available delivery strategies such as intracerebroventricular (ICV) infusion cause significant tissue damage. We designed a novel delivery system that circumvents the blood brain barrier and directly releases growth factors to the brain. Sequential release of the two growth factors is a key in eliciting tissue repair. To control release, we encapsulate pegylated EGF (EGF-PEG) in poly(lactic-co-glycolic acid) (PLGA) nanoparticles and EPO in biphasic microparticles comprised of a PLGA core and a poly(sebacic acid) coating. EGF-PEG and EPO polymeric particles are dispersed in a hyaluronan methylcellulose (HAMC) hydrogel which spatially confines the particles and attenuates the inflammatory response of brain tissue. Our composite-mediated, sequential delivery of EGF-PEG and EPO leads to tissue repair in a mouse stroke model and minimizes damage compared to ICV infusion.

Topics: Absorbable Implants; Animals; Brain; Delayed-Action Preparations; Drug Delivery Systems; Epidermal Growth Factor; Erythropoietin; Humans; Lactic Acid; Male; Methylcellulose; Mice; Mice, Inbred C57BL; Nanoparticles; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Recombinant Proteins; Regeneration; Stroke

Erythropoietin (EPO) has been shown to be neuroprotective in various models of neuronal injury. The aim of the present study was to investigate the beneficial effect of recombinant human EPO (rhEPO) following intracerebral hemorrhage (ICH) and the underlying molecular and cellular mechanisms. ICH was induced using autologous blood injection in adult rats. rhEPO (5000 IU/kg) or vehicle was administered to rats with ICH 2 h following surgery and every 24 h for 1 or 3 days. To study the involvement of the PI3K signaling pathway in the rhEPO‑mediated effect, the PI3K inhibitor wortmannin (15 µg/kg), was intravenously administered to rats with ICH 90 min prior to rhEPO treatment. Brain edema was measured 3 days following ICH and behavioral outcomes were measured at 1, 7, 14, 21 and 28 days following ICH using the modified neurological severity score (mNSS) and the corner turn test. Proinflammatory cytokines, including tumor necrosis factor (TNF)‑α, interleukin (IL)-1β and IL-6, in the ipsilateral striatum were analyzed using an enzyme-linked immunosorbent assay 24 h following ICH. Neuronal apoptosis in the perihematomal area was determined by NeuN and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) double-staining. The results showed that rhEPO treatment reversed ICH, increased brain water content, upregulated proinflammatory cytokines, neuronal loss and apoptosis in the perihematomal area and rescued behavioral deficits in injured rats. Inhibiting the PI3K pathway with wortmannin abolished the rhEPO‑mediated neuroprotective effects. Moreover, western blot analysis showed that rhEPO induced the upregulation of Akt phosphorylation and downregulation of glycogen synthase kinase (GSK)‑3β phosphorylation, which were reversed by pretreatment with wortmannin, indicating the involvement of PI3K signaling in rhEPO-mediated anti-apoptotic and anti-inflammatory effects following ICH. In conclusion, these results suggested that rhEPO may exert its beneficial effects in ICH through the activation of the PI3K signaling pathway.

Topics: Animals; Apoptosis; Behavior, Animal; Blotting, Western; Brain Injuries; Cells, Cultured; Cerebral Hemorrhage; Cytokines; Disease Models, Animal; Epoetin Alfa; Erythropoietin; Fluorescent Antibody Technique; Male; Neuroprotective Agents; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Signal Transduction; Stroke

Topics: Arginine; Drug Therapy, Combination; Erythropoietin; Female; Humans; Male; Stroke; Thrombolytic Therapy; Tissue Plasminogen Activator

Topics: Arginine; Drug Therapy, Combination; Erythropoietin; Female; Humans; Male; Stroke; Thrombolytic Therapy; Tissue Plasminogen Activator

Human recombinant erythropoietin adsorbed on poly(butyl)cyanoacrylate nanoparticles and administered intraperitoneally in a dose of 0.05 mg/kg exhibited a neuroprotective effect in experimental intracerebral posttraumatic hematomas (hemorrhagic stroke) and reduced animal mortality. Human recombinant erythropoietin, native and adsorbed on lactic and glycolic acid copolymer-based nanoparticles, exhibited no antistroke effect on this model. Analysis of reverse transcription PCR products showed that human recombinant erythropoietin adsorbed on poly(butyl)cyanoacrylate nanoparticles more than 2-fold increased the expression of BDNF and NGF neurotrophins in the rat brain frontal cortex and hippocampus.

Topics: Animals; Brain-Derived Neurotrophic Factor; Cerebral Cortex; Cerebral Hemorrhage; Cyanoacrylates; Drug Delivery Systems; Enbucrilate; Erythropoietin; Hematoma; Hippocampus; Humans; Male; Nanoparticles; Nerve Growth Factor; Neuroprotective Agents; Rats; Rats, Wistar; Recombinant Proteins; Stroke

Stroke is a common cause of neonatal brain injury. The subventricular zone is a lifelong source of newly generated cells in rodents, and erythropoietin (EPO) treatment has shown benefit in different animal models of brain injury. The purpose of this study is to investigate the specific role of exogenous EPO on subventricular zone progenitor cell populations in response to neonatal stroke.. Intraventricular injections of green fluorescent protein (GFP)-expressing lentivirus to label subventricular zone precursor cells were made in postnatal day 1 (P1) Long-Evans rats, which then underwent transient middle cerebral artery occlusion on P7. Middle cerebral artery occlusion and sham rats were treated with either vehicle or EPO (1000 U/kg) at reperfusion, 24 hours, and 7 days later. The density of double-labeled DCx+/GFP+, NeuN+/GFP+, O4+/GFP+, GFAP+/GFP+, as well as single-labeled GFP+ and Ki67+ cells, was calculated to determine cell fate outcome in the striatum at 72 hours and 2 weeks after stroke.. There was a significant increase in DCx+/GFP+ and NeuN+/GFP+ neurons and O4+/GFP+ oligodendrocyte precursors, with decreased GFAP+/GFP+ astrocytes at both time points in EPO-middle cerebral artery occlusion animals. There was also a significant increase in GFP+ cells and Ki67+ proliferating cells in EPO compared with vehicle-middle cerebral artery occlusion animals.. These data suggest that subventricular zone neural progenitor cells proliferate and migrate to the site of injury after neonatal stroke and multiple doses of EPO, with a shift in cell fate toward neurogenesis and oligodendrogliosis at both early and late time points. The contribution of local cell proliferation and neurogenesis remains to be determined.

Topics: Animals; Animals, Newborn; Basal Ganglia; Cell Differentiation; Cell Movement; Cell Proliferation; Dose-Response Relationship, Drug; Doublecortin Protein; Erythropoietin; Green Fluorescent Proteins; Infarction, Middle Cerebral Artery; Models, Animal; Neurogenesis; Oligodendroglia; Rats; Rats, Long-Evans; Stroke; Time Factors

Several polymorphisms of vasoactive hormones have been implicated in hypertension. Erythropoietin (EPO) interacts with vasoactive substances, such as angiotensin II. Previously detected single nucleotide polymorphisms in the hypoxia-responsive element of EPO might be associated with hypertension and hypertensive end organ damages.. 400 hypertensive patients and 200 age- and gender-matched normotensive controls were genotyped for an EPO polymorphism [cytosine (C)/thymine (T) single nucleotide polymorphism] at position 3434. Patients were grouped according to their genotype into the CC group (CC genotype) and the CT/TT group (CT and TT genotype). BP was measured by ambulatory BP monitoring.. The CC genotype was present in 87% of hypertensive patients and in 78.5% of controls (p = 0.007). In addition, patients with the CC genotype had higher BP levels compared with CT/TT genotypes (BPsys 143.7 ± 20.4 vs. 136.1 ± 13.5 mm Hg, p = 0.01, and BPdias 85.8 ± 11.6 vs. 82.4 ± 8.9, p = 0.043) despite a nearly identical number of antihypertensive drugs (2.3 ± 1.5 vs. 2.3 ± 1.6; p = 0.257). 100% of the small number of patients with end-stage renal disease (n = 15) had the CC genotype.. The CC genotype of the EPO gene at position 3434 is more frequently found in patients with hypertension and is associated with higher BP levels.

Topics: Adult; Aged; Blood Pressure; Blood Pressure Monitoring, Ambulatory; Erythropoietin; Female; Genotype; Homozygote; Humans; Hypertension, Renal; Hypoxia; Male; Middle Aged; Myocardial Infarction; Polymorphism, Genetic; Stroke; Vascular Diseases

Drug delivery to the brain is challenging because systemic delivery requires high doses to achieve diffusion across the blood-brain barrier and often results in systemic toxicity. Intracerebroventricular implantation of a minipump/catheter system provides local delivery, yet results in brain tissue damage and can be prone to infection. An alternate local delivery strategy, epi-cortical delivery, releases the biomolecule directly to the brain while causing minimal tissue disruption. We pursued this strategy with a hyaluronan/methyl cellulose (HAMC) hydrogel for the local release of erythropoietin to induce endogenous neural stem and progenitor cells of the subventricular zone to promote repair after stroke injury in the mouse brain. Erythropoeitin promotes neurogenesis when delivered intraventricularly, thereby making it an ideal biomolecule with which to test this new epi-cortical delivery strategy. We investigated HAMC in terms of the host tissue response and the diffusion of erythropoeitin therefrom in the stroke-injured brain for neural repair. Erythropoietin delivered from HAMC at 4 and 11 days post-stroke resulted in attenuated inflammatory response, reduced stroke cavity size, increased number of both neurons in the peri-infarct region and migratory neuroblasts in the subventricular zone, and decreased apoptosis in both the subventricular zone and the injured cortex. We demonstrate that HAMC-mediated epi-cortical administration is promising for minimally invasive delivery of erythropoeitin to the brain.

Topics: Animals; Apoptosis; Brain; Cell Count; Cerebral Cortex; DNA-Binding Proteins; Doublecortin Domain Proteins; Drug Administration Routes; Drug Delivery Systems; Erythropoietin; Humans; Hyaluronic Acid; Hydrogel, Polyethylene Glycol Dimethacrylate; In Situ Nick-End Labeling; Inflammation; Ki-67 Antigen; Methylcellulose; Mice; Mice, Inbred C57BL; Microtubule-Associated Proteins; Nerve Tissue Proteins; Neuropeptides; Nuclear Proteins; Receptors, Erythropoietin; Stem Cells; Stroke

Pyruvate is known to be cytoprotective through antioxidant and anti-inflammatory mechanisms. We tested the hypothesis that pyruvate protects the brain against ischemia-reperfusion injury by inducing endogenous erythropoietin (EPO) expression.. Pyruvate's protective effect was evaluated in C6 glioma cells and HT22 neuronal cells subjected to transient oxygen glucose deprivation. Cell viability (calcein AM assay) and expression of hypoxia-inducible factor-1α, EPO, Akt and Erk (immunoblot), and EPO receptor (reverse transcription-polymerase chain reaction) were analyzed. Transient focal cerebral ischemia in rats was induced by 2 hours middle cerebral artery occlusion followed by 24 hours reperfusion. Pyruvate or saline was infused from 60 minutes occlusion until 30 minutes reperfusion. Lesion volume and DNA fragmentation were assessed by 2,3,5-triphenyltetrazolium staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay, respectively. Immunoblots were conducted to determine cerebral EPO contents.. Pyruvate increased cell viability, hypoxia-inducible factor-1α, EPO, and Akt phosphorylation. Small interfering RNA suppression of hypoxia-inducible factor-1α and EPO abolished pyruvate-induced cytoprotection. In the rat stroke model, pyruvate reduced lesion volume by 84% and DNA fragmentation by 77% versus controls; increased EPO content paralleled these cerebroprotective actions of pyruvate.. Pyruvate activation of the hypoxia-inducible factor-1α-EPO signaling cascade in neurons and glia could protect the brain from ischemia-reperfusion injury.

Topics: Animals; Brain; Cell Line, Tumor; Disease Models, Animal; Erythropoietin; Gene Expression Regulation; Hypoxia-Inducible Factor 1, alpha Subunit; Male; Mice; Proto-Oncogene Proteins c-akt; Pyruvic Acid; Rats; Rats, Sprague-Dawley; Receptors, Erythropoietin; Reperfusion Injury; Signal Transduction; Stroke

Topics: Chronic Disease; Epoetin Alfa; Erythropoietin; Heart Failure; Hematinics; Humans; Kidney Diseases; Patient Education as Topic; Physician-Patient Relations; Recombinant Proteins; Renal Dialysis; Risk Assessment; Risk Factors; Risk Management; Stroke; United States; United States Food and Drug Administration

Global geographic disparities in stroke mortality rates are substantial. In the US alone, higher stroke mortality rates are reported in the Southeast part particularly along the coastline while lower rates have been observed in the Mountain region. The phenomenon has been called the "stroke belt". Although many theories have attempted to explain such nonrandom distribution of stroke mortality rates, no conclusive explanations have been drawn so far. I hypothesize that this nonrandom stroke distribution is related to regional differences in individual levels of erythropoietin (EPO), a hormone, which production depends on the tissue hypoxia due to variation in altitude. If successful, future studies based on this hypothesis may open up new avenues for treatment of such an important health issue as stroke. More importantly, future studies based on this theory may shed the lights on the mechanism of stroke as well as other diseases which have nonrandom geographic distribution not only in the US but also internationally.

Topics: Altitude; Biomarkers; Disease Outbreaks; Erythropoietin; Humans; Models, Biological; Stroke

Erythropoietin (EPO) is a neuroprotective cytokine in models of ischemic and nervous system injury, where it reduces neuronal apoptosis and inflammatory cytokines and increases neurogenesis and angiogenesis. EPO also improves cognition in healthy volunteers and schizophrenic patients. We studied the effect of EPO administration on the gene-expression profile in the ischemic cortex of rats after cerebral ischemia at early time points (2 and 6 h). EPO treatment up-regulated genes already increased by ischemia. Hierarchical clustering and analysis of overrepresented functional categories identified genes implicated in synaptic plasticity-Arc, BDNF, Egr1, and Egr2, of which Egr2 was the most significantly regulated. Up-regulation of Arc, BDNF, Dusp5, Egr1, Egr2, Egr4, and Nr4a3 was confirmed by quantitative PCR. We investigated the up-regulation of Egr2/Krox20 further because of its role in neuronal plasticity. Its elevation by EPO was confirmed in an independent in vivo experiment of cerebral ischemia in rats. Using the rat neuroblastoma B104, we found that wild-type cells that do not express EPO receptor (EPOR) do not respond to EPO by inducing Egr2. However, EPOR-expressing B104 cells induce Egr2 early upon incubation with EPO, indicating that Egr2 induction is a direct effect of EPO and that EPOR mediates this effect. Because these changes occur in vivo before decreased inflammatory cytokines or neuronal apoptosis is evident, these findings provide a molecular mechanism for the neuroreparative effects of cytokines and suggest a mechanism of neuroprotection by which promotion of a plastic phenotype results in decreased inflammation and neuronal death.

Topics: Animals; Brain; Erythropoietin; Gene Expression Profiling; Neuronal Plasticity; Polymerase Chain Reaction; Rats; Stroke

Topics: Algorithms; Anemia; Chronic Disease; Darbepoetin alfa; Dose-Response Relationship, Drug; Erythropoietin; Hematinics; Hemoglobins; Humans; Kidney Diseases; Risk Factors; Stroke; United States; United States Food and Drug Administration

The promotion of post-ischaemic motor recovery remains a major challenge in clinical neurology. Recently, plasticity-promoting effects have been described for the growth factor erythropoietin in animal models of neurodegenerative diseases. To elucidate erythropoietin's effects in the post-acute ischaemic brain, we examined how this growth factor influences functional neurological recovery, perilesional tissue remodelling and axonal sprouting of the corticorubral and corticobulbar tracts, when administered intra-cerebroventricularly starting 3 days after 30 min of middle cerebral artery occlusion. Erythropoietin administered at 10 IU/day (but not at 1 IU/day), increased grip strength of the contralesional paretic forelimb and improved motor coordination without influencing spontaneous locomotor activity and exploration behaviour. Neurological recovery by erythropoietin was associated with structural remodelling of ischaemic brain tissue, reflected by enhanced neuronal survival, increased angiogenesis and decreased reactive astrogliosis that resulted in reduced scar formation. Enhanced axonal sprouting from the ipsilesional pyramidal tract into the brainstem was observed in vehicle-treated ischaemic compared with non-ischaemic animals, as shown by injection of dextran amines into both motor cortices. Despite successful remodelling of the perilesional tissue, erythropoietin enhanced axonal sprouting of the contralesional, but not ipsilesional pyramidal tract at the level of the red and facial nuclei. Moreover, molecular biological and histochemical studies revealed broad anti-inflammatory effects of erythropoietin in both hemispheres together with expression changes of plasticity-related molecules that facilitated contralesional axonal growth. Our study establishes a plasticity-promoting effect of erythropoietin after stroke, indicating that erythropoietin acts via recruitment of contralesional rather than of ipsilesional pyramidal tract projections.

Topics: Analysis of Variance; Animals; Blotting, Western; Brain; Brain Ischemia; Erythropoietin; Exploratory Behavior; Hand Strength; Immunohistochemistry; Male; Mice; Motor Activity; Neuronal Plasticity; Neurons; Recovery of Function; Reverse Transcriptase Polymerase Chain Reaction; Rotarod Performance Test; Stroke

Prophylactic neuroprotection against stroke could reduce stroke burden in thousands of patients at high risk of stroke, including those with recent transient ischemic attacks (TIAs). Prolyl hydroxylase inhibitors (PHIs), such as deferoxamine (DFO), reduce stroke volume when administered at high doses in the peristroke period, which is largely mediated by the hypoxia-inducible transcription factor (HIF-1). Yet, in vitro experiments suggest that PHIs may also induce neuroprotection independent of HIF-1. In this study, we examine chronic, prophylactic, low-dose treatment with DFO, or another iron chelator deferasirox (DFR), to determine whether they are neuroprotective with this paradigm and mediate their effects through a HIF-1-dependent mechanism. In fact, prophylactic administration of low-dose DFO or DFR significantly reduces stroke volume. Surprisingly, DFO remained neuroprotective in mice haploinsufficient for HIF-1 (HIF-1+/-) and transgenic mice with conditional loss of HIF-1 function in neurons and astrocytes. Similarly, DFR was neuroprotective in HIF-1+/- mice. Neither DFO nor DFR induced expression of HIF-1 targets. Thus, low-dose chronic administration of DFO or DFR induced a prolonged neuroprotective state independent of HIF-1 function. As DFR is an orally administered and well-tolerated medication in clinical use, it has promise for prophylaxis against stroke in patients at high risk of stroke.

Topics: Animals; Astrocytes; Benzoates; Brain; Cyclic AMP Response Element-Binding Protein; Deferasirox; Deferoxamine; Erythropoietin; Extracellular Signal-Regulated MAP Kinases; Gene Deletion; Hypoxia-Inducible Factor 1; Iron Chelating Agents; Mice; Mice, Knockout; Neurons; Neuroprotective Agents; Phosphorylation; Proto-Oncogene Proteins c-akt; Stroke; Triazoles

Endothelial progenitor cell (EPC) mobilization from the bone marrow was considered to improve outcome after ischemic stroke. Erythropoietin (EPO) might be a potential candidate stroke drug that increases the number of circulating EPCs. In the previous issue of Critical Care, Yip and colleagues investigated the effect of EPO in stroke patients on both clinical outcome and EPC stimulation. Although beneficial effects of EPO were observed, several issues regarding EPO's suitability as a stroke drug remain.

Topics: Endothelial Cells; Erythropoietin; Female; Hematinics; Humans; Male; Stem Cells; Stroke

Topics: Endothelial Cells; Erythropoietin; Female; Hematinics; Humans; Male; Stem Cells; Stroke

The authors evaluated the patterns of use and the risk of thromboembolic events (TEE) associated with erythropoietin-stimulating agents (ESAs) in older patients with metastatic breast cancer who were receiving chemotherapy.. The study was retrospective and used the SEER-Medicare linked database. Stage IV breast cancer patients diagnosed from 1995-2005, treated with chemotherapy, ≥66 years old, with full coverage of Medicare A and B were included. The World Health Organization's International Classification of Diseases (ICD-9) and the Healthcare Common Procedure Coding System (HCPCS) were used to identify the use of ESAs, chemotherapy, and complications of therapy. Analyses included descriptive statistics and logistic regression.. Of 2266 women, 980 (43.3%) received ESAs, and 1286 (56.7%) did not. Patients diagnosed after 1999 or who received treatment with taxanes, anthracyclines, or vinorelbine were more likely to receive ESAs. Patients receiving ESAs had higher rates of stroke (18.5% vs 15.1%, P = .031); deep-vein thrombosis (DVT; 21.3% vs 14.4%, P<.001), other/unspecified thromboembolic event (TEE; 19.8% vs 14.7%, P = .001), and any clot (31.3% vs 23.4%, P<.0001). In multivariate analysis, patients receiving ESAs had increased risk for DVT (odds ratio [OR], 1.36; 95% confidence interval [CI], 1.05-1.75), and any clot (OR, 1.26; 95% CI, 1.02-1.57). A dose-dependent effect was evident for stroke, DVT, other TEE, and any clot.. In this cohort of patients, the use of ESAs increased the risk of TEEs, with a dose-dependent effect for stroke, DVT, other TEE, and any clot. The data show that among patients treated with chemotherapy and ESAs for metastatic breast cancer, TEEs are a common event. Therefore, caution is recommended when using these agents.

Topics: Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Breast Neoplasms; Erythropoietin; Female; Humans; Medicare; Neoplasm Metastasis; Retrospective Studies; SEER Program; Stroke; Thrombosis; United States; Venous Thrombosis

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

Topics: Anemia; Darbepoetin alfa; Diabetes Mellitus, Type 2; Erythropoietin; Female; Humans; Male; Renal Insufficiency, Chronic; Stroke

The neuroprotective activity of recombinant human erythropoietin (r-HuEpo) sorbed on poly(butyl)cyanoacrilate nanoparticles (EPO-PBCA) and on polylactic-co-glycolic acid nanoparticles (EPO-PLGA) has been studied on Wistar rats with intracerebral post-traumatic hematoma (model of hemorrhagic stroke) (IPH-HS) in comparison to native r-HuEpo. It is established that EPO-PBCA produced a protective effect in rats after IPH-HS that was manifested by a decrease in the number of animals with neurological disorders such as circus movement, paresis, and paralysis of hind limbs; the drug also improved coordination (rotating rod test), reduced the number of lost animals, and decreased the loss weight among survived rats. In addition, EPO-PBCA optimized the research behavior of rats with IPH-HS in the open field test and prevented amnesia of passive avoidance reflex (PAR), which was caused by the IPH-HS. These effects were manifested during a two-week observation period. EPO-PLGA has a similar but much less pronounced effect on the major disorders caused by IPH-HS. The efficiency of native r-HuEpo as a neuropotective agent was insignificant and only manifested by decrease in the number of lost animals with IPH-HS.

Topics: Adsorption; Amnesia; Animals; Cerebral Hemorrhage; Disease Models, Animal; Enbucrilate; Erythropoietin; Humans; Lactic Acid; Male; Motor Activity; Nanoparticles; Neuroprotective Agents; Paralysis; Paresis; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Rats; Rats, Wistar; Recombinant Proteins; Stroke; Survival Rate; Weight Loss

Topics: Brain Ischemia; Endothelium, Vascular; Erythropoietin; Humans; Recombinant Proteins; Stroke

Topics: Adult; Anemia; Child; Darbepoetin alfa; Erythropoietin; Female; Hematinics; Hemoglobins; Humans; Male; Renal Insufficiency, Chronic; Risk; Sex Factors; Stroke

Topics: Anemia; Cerebral Hemorrhage; Darbepoetin alfa; Drug Therapy, Combination; Erythropoietin; Female; Hematinics; Humans; Male; Renal Insufficiency, Chronic; Stroke; Tissue Plasminogen Activator

Topics: Anemia; Darbepoetin alfa; Diabetes Mellitus, Type 2; Erythropoietin; Female; Hematinics; Hemoglobins; Humans; Iron; Male; Neoplasms; Renal Insufficiency, Chronic; Stroke; Treatment Outcome

Topics: Anemia; Darbepoetin alfa; Erythropoietin; Female; Hematinics; Hemoglobins; Humans; Male; Platelet Count; Renal Dialysis; Renal Insufficiency, Chronic; Risk; Stroke

Topics: Erythropoietin; Humans; Neuroprotective Agents; Point-of-Care Systems; Receptors, Erythropoietin; Stroke; Thrombolytic Therapy

Topics: Brain Ischemia; Drug Evaluation, Preclinical; Erythropoietin; Humans; Meta-Analysis as Topic; Stroke

Neurorestorative therapy is the next frontier in the treatment of stroke. An expanding body of evidence supports the theory that after stroke, certain cellular changes occur that resemble early stages of development. Increased expression of developmental proteins in the area bordering the infarct suggest an active repair or reconditioning response to ischemic injury. Neurorestorative therapy targets parenchymal cells (neurons, oligodendrocytes, astrocyes, and endothelial cells) to enhance endogenous neurogenesis, angiogenesis, axonal sprouting, and synaptogenesis to promote functional recovery. Pharmacological treatments include statins, phosphodiesterase 5 inhibitors, erythropoietin, and nitric oxide donors that have all improved functional outcome after stroke in the preclinical arena. Thymosin beta4 (Tbeta4) is expressed in both the developing and adult brain and it has been shown to stimulate vasculogenesis, angiogenesis, and arteriogenesis in the postnatal and adult murine cardiac myocardium. In this manuscript, we describe our rationale and techniques to test our hypothesis that Tbeta4 may be a candidate neurorestorative agent.

Topics: Adult; Brain; Endothelial Cells; Erythropoietin; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Neurogenesis; Neurons; Nitric Oxide Donors; Oligodendroglia; Recombinant Proteins; Recovery of Function; Stroke; Thymosin

Erythropoietin (EPO), a hematopoietic cytokine, enhances neurogenesis and angiogenesis during stroke recovery. In the present study, we examined the effect of EPO on oligodendrogenesis in a rat model of embolic focal cerebral ischemia.. Recombinant human EPO (rhEPO) at a dose of 5,000 U/kg (n = 18) or saline (n = 18) was intraperitoneally administered daily for 7 days starting 24 h after stroke onset. Treatment with rhEPO augmented actively proliferating oligodendrocyte progenitor cells (OPCs) measured by NG2 immunoreactive cells within the peri-infarct white matter and the subventricular zone (SVZ), but did not protect against loss of myelinating oligodendrocytes measured by cyclic nucleotide phosphodiesterase (CNPase) positive cells 7 days after stroke. However, 28 and 42 days after stroke, treatment with rhEPO significantly increased myelinating oligodendrocytes and myelinated axons within the peri-infarct white matter. Using lentivirus to label subventricular zone (SVZ) neural progenitor cells, we found that in addition to the OPCs generated in the peri-infarct white matter, SVZ neural progenitor cells contributed to rhEPO-increased OPCs in the peri-infarct area. Using bromodeoxyuridine (BrdU) for birth-dating cells, we demonstrated that myelinating oligodendrocytes observed 28 days after stroke were derived from OPCs. Furthermore, rhEPO significantly improved neurological outcome 6 weeks after stroke. In vitro, rhEPO increased differentiation of adult SVZ neural progenitor cells into oligodendrocytes and enhanced immature oligodendrocyte cell proliferation.. Our in vivo and in vitro data indicate that EPO amplifies stroke-induced oligodendrogenesis that could facilitate axonal re-myelination and lead to functional recovery after stroke.

Topics: Animals; Axons; Cell Division; Erythropoietin; Oligodendroglia; Rats; Recombinant Proteins; Stroke

Use of erythropoiesis-stimulating agents (ESA) has been reported to increase the incidence of cardiovascular diseases at target Hb levels by more than 12.0 g/dl. The recent TREAT study found an increased incidence of stroke and cancer when maintaining the Hb level at 12.5 g/dl in diabetic patients.. Surveillance of Epoetin-Adverse Events of Stroke and Cancer (SEASCAN) was a cross-sectional study conducted under urgent conditions by the Committee on CKD Initiatives of the Japanese Society of Nephrology. Patients who were at least 18 years old and had CKD stage 4 and 5, namely, eGFR <30 ml/min/1.73 m(2), and who had visited the outpatient department of the participating facilities between December 2009 and January 2010 with at least 6 months of prior medical treatment in the participating facilities were eligible to participate in the study.. Of 7,415 patients with CKD stage 4 and 5, 3,653 (49.3%), 879 (11.9%) and 2,883 (38.9%) patients received no epoetin, epoetin for less than 6 months and epoetin for at least 6 months, respectively. In patients who did not use epoetin, use of epoetin for less than 6 months and use of epoetin for at least 6 months, the numbers of patients with stroke were 38 (1.0%), 8 (0.9%) and 27 (0.9%), respectively, and those with newly diagnosed or exacerbated malignancy were 88 (2.4%), 30 (3.4%) and 71 (2.5%), respectively, demonstrating insignificant associations between outcome and duration of treatment with epoetin (P for trend = 0.666 in stroke and 0.836 in malignancy).. No significant increase in the risk of developing symptomatic stroke and cancer was observed for the use of epoetin in current clinical practice in Japan.

Topics: Aged; Cross-Sectional Studies; Epoetin Alfa; Erythropoietin; Female; Hematinics; Humans; Male; Middle Aged; Neoplasms; Recombinant Proteins; Renal Insufficiency, Chronic; Stroke

Erythropoietin (EPO), a hematopoietic cytokine, exerts neuroprotective effects in experimental stroke. In the present study, we investigated the effect of recombinant human EPO (rhEPO) in combination with tissue plasminogen activator (tPA) on embolic stroke.. Rats subjected to embolic middle cerebral artery occlusion (MCAO) were treated with rhEPO (5000 U/kg) in combination with tPA (10 mg/kg) at 2 or 6 hours after MCAO. Control groups consisted of ischemic rats treated with rhEPO (5000 U/kg) alone, tPA (10 mg/kg) alone, or saline at 2 or 6 hours after MCAO.. The combination therapy of rhEPO and tPA initiated 6 hours after MCAO did not reduce the ischemic lesion volume and significantly (P<0.05) increased the incidence of brain hemorrhage measured by frequency of gross hemorrhage and a quantitative spectrophotometric hemoglobin assay compared with rats treated with rhEPO alone and tPA alone. However, when the combination therapy was initiated 2 hours after MCAO, the treatment significantly (P<0.05) reduced the lesion volume and did not substantially increase the incidence of hemorrhagic transformation compared with saline-treated rats. Immunostaining analysis revealed that the combination therapy of rhEPO and tPA at 6 hours significantly (P<0.05) increased matrix metalloproteinase-9, NF-kappaB, and interleukin-1 receptor-associated kinase-1 immunoreactive cerebral vessels compared with rats treated with rhEPO alone and saline.. EPO exacerbates tPA-induced brain hemorrhage without reduction of ischemic brain damage when administered 6 hours after stroke in a rat model of embolic MCAO and that matrix metalloproteinase-9, NF-kappaB, and interleukin-1 receptor-associated kinase-1 upregulated by the delayed combination therapy may contribute to augmentation of brain hemorrhage.

Topics: Analysis of Variance; Animals; Blotting, Western; Brain; Chi-Square Distribution; Drug Therapy, Combination; Erythropoietin; Immunohistochemistry; Interleukin-1 Receptor-Associated Kinases; Intracranial Hemorrhages; Male; Matrix Metalloproteinase 9; NF-kappa B; Rats; Rats, Wistar; Stroke; Time Factors; Tissue Plasminogen Activator; Treatment Outcome

Using magnetic resonance imaging (MRI) protocols of T(2)-, T(2)*-, diffusion- and susceptibility-weighted imaging (T2WI, T2*WI, DWI, and SWI, respectively) with a 7T system, we tested the hypothesis that treatment of embolic stroke with erythropoietin (EPO) initiated at 24 hr and administered daily for 7 days after stroke onset has benefit in repairing ischemic cerebral tissue. Adult Wistar rats were subjected to embolic stroke by means of middle cerebral artery occlusion (MCAO) and were randomly assigned to a treatment (n = 11) or a control (n = 11) group. The treated group was given EPO intraperitoneally at a dose of 5,000 IU/kg daily for 7 days starting 24 hr after MCAO. Controls were given an equal volume of saline. MRI was performed at 24 hr and then weekly for 6 weeks. MRI and histological measurements were compared between groups. Serial T2WI demonstrated that expansion of the ipsilateral ventricle was significantly reduced in the EPO-treated rats. The volume ratio of ipsilateral parenchymal tissue relative to the contralateral hemisphere was significantly increased after EPO treatment compared with control animals, indicating that EPO significantly reduces atrophy of the ipsilateral hemisphere, although no significant differences in ischemic lesion volume were observed between the two groups. Angiogenesis and white matter remodeling were significantly increased and occurred earlier in EPO-treated animals than in the controls, as evident from T2*WI and diffusion anisotropy maps, respectively. These data indicate that EPO treatment initiated 24 hr poststroke promotes angiogenesis and axonal remodeling in the ischemic boundary, which may potentially reduce atrophy of the ipsilateral hemisphere.

Topics: Animals; Atrophy; Disease Models, Animal; Erythropoietin; Intracranial Embolism; Magnetic Resonance Imaging; Male; Nerve Degeneration; Neuroprotective Agents; Random Allocation; Rats; Rats, Wistar; Recombinant Proteins; Stroke

Erythropoietin (EPO) is a potent neuroprotective agent that could be developed as a new treatment for stroke. However, the blood-brain barrier (BBB) is intact in the early hours after stroke when neuroprotection is still possible, and EPO does not cross the intact BBB. To enable BBB transport, human EPO was re-engineered as an IgG-EPO fusion protein, wherein the IgG part is a monoclonal antibody (MAb) against the human insulin receptor (HIR). The HIRMAb acts as a BBB molecular Trojan horse to ferry the fused EPO across the BBB via transport on the BBB insulin receptor. The HIRMAb part of the HIRMAb-EPO fusion protein does not recognize the rat insulin receptor. However, the EPO part of the fusion protein does recognize the rat EPO receptor. Therefore, the neuroprotective properties of the HIRMAb-EPO fusion protein were investigated with a permanent middle cerebral artery occlusion model in the rat. The HIRMAb-EPO fusion protein was injected into the ipsilateral brain under stereotaxic guidance. High doses of the HIRMAb-EPO fusion protein (61pmol) completely eliminated both cortical and sub-cortical infarction. Lower doses of the fusion protein (4.5pmol) eliminated the cortical infarct with no significant effect on sub-cortical infarct. The neurologic deficit was reduced by 35% and 90%, respectively, by the 4.5 and 61pmol doses of the HIRMAb-EPO fusion protein. In conclusion, these studies demonstrate the biological activity of the HIRMAb-EPO fusion protein in the brain in vivo, and that EPO retains neuroprotective properties following fusion to the HIRMAb BBB Trojan horse.

Topics: Animals; Cerebral Cortex; Dose-Response Relationship, Drug; Erythropoietin; Functional Laterality; Immunoglobulin G; Infarction, Middle Cerebral Artery; Male; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Recombinant Fusion Proteins; Recombinant Proteins; Stereotaxic Techniques; Stroke

Neuroprotective, but not hematopoietic, variants of erythropoietin (EPO), such as Neuro-EPO, are promising candidates for treatment in the acute and subacute stroke phase. Characterized by its low sialic acid content and therefore exhibiting a very short plasma half-life, Neuro-EPO can probably not be administered systemically via the blood. As such, alternate routes of delivery are required. In their paper that now appears in TheScientificWorldJOURNAL, Rodríguez Cruz and colleagues provide evidence that Neuro-EPO promotes neurological recovery in the ischemic gerbil brain in a way that is similarly potent, if not superior, to systemically administered EPO. In view of the potential clinical use of Neuro-EPO, stringent proof-of-concept studies are urgently needed to define (1) how intranasally delivered Neuro-EPO reaches the brain, (2) which concentrations are achieved in the ischemic and nonischemic brain tissue of rodents and nonhuman primates, and (3) which are the mechanisms via which Neuro-EPO protects from injury. Only with such information should decisions be made whether intranasal Neuro-EPO may be evaluated in human patients.

Topics: Administration, Intranasal; Animals; Brain Ischemia; Cognition; Disease Models, Animal; Erythropoietin; Gerbillinae; Humans; Neuroprotective Agents; Recombinant Proteins; Stroke; Treatment Outcome

The hematopoietic growth factor erythropoietin (EPO) and its neuroprotective, but not hematopoietic, variants asialoEPO, carbamylated EPO (CEPO), and low sialic acid EPO (Neuro-EPO) are attractive candidates for stroke treatment. Due to their large molecular weight, these proteins enter the brain only to a minor extent when intravenously administered, which has raised the question for alternative delivery strategies, among which intranasal delivery may certainly be an attractive choice, as the review by Garcia Rodriguez and Sosa Teste in this journal points out. Before this strategy may be considered clinically applicable, however, more and, in particular, quantitative information is needed about (a) the temporospatial accumulation of EPO and its variants in the brain tissue both in animals and nonhuman primates, and (b) the accumulation of EPO and its variants in the human cerebrospinal fluid.

Topics: Administration, Intranasal; Asialoglycoproteins; Blood-Brain Barrier; Brain Ischemia; Erythropoietin; Humans; Recombinant Proteins; Stroke

Perioperative beta-blockade and anemia are independent predictors of increased stroke and mortality by undefined mechanisms. This study investigated the effect of beta-blockade on cerebral tissue oxygen delivery in an experimental model of blood loss and fluid resuscitation (hemodilution).. Anesthetized rats were treated with metoprolol (3 mg x kg) or saline before undergoing hemodilution with pentastarch (1:1 blood volume exchange, 30 ml x kg). Outcomes included cardiac output, cerebral blood flow, and brain (PBrO2) and kidney (PKO2) tissue oxygen tension. Hypoxia inducible factor-1alpha (HIF-1alpha) protein levels were assessed by Western blot. Systemic catecholamines, erythropoietin, and angiotensin II levels were measured.. Hemodilution increased heart rate, stroke volume, cardiac output (60%), and cerebral blood flow (50%), thereby maintaining PBrO2 despite an approximately 50% reduction in blood oxygen content (P < 0.05 for all). By contrast, PKO2 decreased (50%) under the same conditions (P < 0.05). Beta-blockade reduced baseline heart rate (20%) and abolished the compensatory increase in cardiac output after hemodilution (P < 0.05). This attenuated the cerebral blood flow response and reduced PBrO2 (50%), without further decreasing PKO2. Cerebral HIF-1alpha protein levels were increased in beta-blocked hemodiluted rats relative to hemodiluted controls (P < 0.05). Systemic catecholamine and erythropoietin levels increased comparably after hemodilution in both groups, whereas angiotensin II levels increased only after beta-blockade and hemodilution.. Cerebral tissue oxygen tension is preferentially maintained during hemodilution, relative to the kidney, despite elevated systemic catecholamines. Acute beta-blockade impaired the compensatory cardiac output response to hemodilution, resulting in a reduction in cerebral tissue oxygen tension and increased expression of HIF-1alpha.

Topics: Adrenergic beta-Antagonists; Angiotensin II; Animals; Brain; Cardiac Output; Catecholamines; Cerebrovascular Circulation; Erythropoietin; Hemodilution; Hypoxia-Inducible Factor 1, alpha Subunit; Male; Metoprolol; Oxygen; Rats; Rats, Sprague-Dawley; Stroke

Topics: Animals; Erythropoietin; Humans; Neuroprotective Agents; Stroke

Stroke remains one of the most urgent medical problems of our times. The failure of most neuroprotective drugs in clinical trials led to the initiation of the Stroke Therapy Academic Industry Roundtable guidelines. Due to this improvement, the positive clinical trial results with the free radical scavenger NXY-059 (SAINT I) was encouraging. However, the subsequent SAINT II trial did not confirm these results. In this article we critically review the history of preclinical and clinical trials based on experience of NXY-059 development and present recommendations for potential future preclinical and clinical development of neuroprotective stroke therapy.

Topics: Animals; Antioxidants; Benzenesulfonates; Brain; Clinical Trials as Topic; Disease Models, Animal; Drug Evaluation; Erythropoietin; Granulocyte Colony-Stimulating Factor; Humans; Magnetic Resonance Imaging; Neuroprotective Agents; Practice Guidelines as Topic; Stroke

Recent studies suggest that proliferation in the adult forebrain subventricular zone increases in response to a forebrain stroke and intraventricular infusions of growth factors enhance this response. The potential for growth factor infusions to regenerate the damaged motor cortex and promote recovery of motor function after stroke has not been examined. Here, we report that intraventricular infusions of epidermal growth factor and erythropoietin together, but not individually, promote substantial regeneration of the damaged cerebral cortex and reverse impairments in spontaneous and skilled motor tasks, in a rat model of stroke. Cortical regeneration and functional recovery occurred even when growth factor administration was delayed for up to 7 days after the stroke-induced lesion. Cell tracking demonstrated the contribution of neural precursors originating in the forebrain subventricular zone to the regenerated cortex. Strikingly, removal of the regenerated cortical tissue reversed the growth factor-induced functional recovery. These findings reveal that specific combinations of growth factors can mobilize endogenous adult neural stem cells to promote cortical tissue re-growth and functional recovery after stroke.

Topics: Animals; Antimetabolites, Antineoplastic; Bromodeoxyuridine; Cerebral Cortex; Epidermal Growth Factor; Erythropoietin; Forelimb; Immunohistochemistry; Intercellular Signaling Peptides and Proteins; Male; Motor Cortex; Movement; Nerve Regeneration; Psychomotor Performance; Rats; Rats, Long-Evans; Retroviridae; Reverse Transcriptase Polymerase Chain Reaction; Stroke; Swimming

Epidemiological studies report that a third of the cases of anaemia in older persons is unexplained. We compared erythropoietin (EPO), inflammatory markers and major comorbidities between older subjects with normal haemoglobin levels and those with different aetiologic forms of anaemia, including unexplained anaemia. Participants were a representative sample of 964 persons aged > or =65 years, with no evidence of bleeding, complete blood tests, and a complete blood count within 6 h of phlebotomy. Anaemia was defined as haemoglobin <130 g/l in men and 120 g/l in women, and classified as a result of chronic kidney disease, iron deficiency, chronic disease and B12/folate deficiency anaemia, or unexplained anaemia based on standard criteria. Of the 124 anaemic participants, 42 (36.8%) had unexplained anaemia. Participants with anaemia of chronic diseases had significantly higher interleukin-6 (IL-6) and C-reactive protein (CRP) levels, while those with unexplained anaemia had significantly lower CRP than non-anaemic controls. Iron deficiency anaemia was characterised by significantly higher EPO levels compared with other types of anaemia and normal haemoglobin, B12 and/or folate deficiency. Unexplained anaemia was characterised by unexpectedly low EPO and low lymphocyte count. Unexplained anaemia is associated with reduced kidney EPO response, low levels of pro-inflammatory markers and low lymphocyte counts.

Topics: Aged; Aging; Anemia; Biomarkers; C-Reactive Protein; Cardiovascular Diseases; Case-Control Studies; Diabetes Mellitus; Erythropoietin; Female; Health Surveys; Humans; Inflammation Mediators; Interleukin-6; Italy; Kidney Diseases; Lymphocyte Count; Male; Osteoarthritis; Parkinson Disease; Stroke; Tumor Necrosis Factor-alpha

Topics: Angiotensin II Type 1 Receptor Blockers; Benzimidazoles; Biphenyl Compounds; Erythropoietin; Humans; Randomized Controlled Trials as Topic; Stroke; Tetrazoles

Cerebral ischemia disrupts the neurovascular unit, involving death of neuronal, glial, and endothelial cells (ECs) in the core and penumbra regions. Whereas the neuroprotective effect of recombinant human erythropoietin (rhEPO) has been widely investigated, its effects on ECs remain elusive. We now report the effects of rhEPO treatment on EC death and neurovasculature repair following a focal ischemic stroke in postnatal day 7 neonatal rats. rhEPO (5000 U/kg i.p.) was administered 60 min after ischemia and for the next 3 days. Western blot analysis revealed increased expression of neurovascular remodeling proteins, including Tie-1, angiopoietin-2, and basic fibroblast growth factor in rhEPO-treated pups. rhEPO treatment significantly reduced EC death in the ischemic penumbra region 12 to 72 h after ischemia examined by immunostaining of terminal deoxynucleotidyl transferase dUTP nick-end labeling and EC marker glucose transporter-1 (GLUT-1). Treatment with rhEPO increased proliferation of ECs and neuronal cells, revealed by costaining of 5-bromo-2'-deoxyuridine with GLUT-1 or with the neuronal marker protein (NeuN) 7 to 21 days after stroke. Specifically, rhEPO increased number of NeuN-positive cells in close proximity to proliferating microvessels. These results suggest for the first time that, in addition to its protection on neural cells, EPO protects ECs and promotes the neurovascular unit repair, which may contribute to its therapeutic benefits after neonatal ischemic stroke.

Topics: Angiopoietin-2; Animals; Animals, Newborn; Apoptosis; Blotting, Western; Carotid Arteries; Cell Proliferation; Cerebral Arteries; Endothelial Cells; Erythropoietin; Fibroblast Growth Factor 2; Glucose Transporter Type 1; Humans; Immunohistochemistry; Ligation; Neovascularization, Physiologic; Nervous System; Neurons; Rats; Rats, Wistar; Receptor, TIE-1; Recombinant Proteins; Stroke; Vascular Endothelial Growth Factor A

Erythropoietin (EPO) is a pleiotropic cytokine with a therapeutic potential that goes well beyond the treatment of anaemia. The study by Wang et al (2007b) examined the protective effects of EPO in a rat model of embolic stroke. The efficacy and haematological side effects of EPO were compared to those of a carbamylated EPO variant (CEPO). Treatment with EPO dose-dependently reduced infarct volume and improved long-term functional outcome. However, an increase in hematocrit was seen even for doses of EPO that did not offer neuroprotection. These data do not suggest the existence of a therapeutic window between effect and side effect for treatment with EPO. Treatment with CEPO was without haematological side effects.

Topics: Animals; Disease Models, Animal; Dose-Response Relationship, Drug; Erythropoietin; Hematocrit; Neuroprotective Agents; Rats; Stroke

Recombinant human erythropoietin (rhEPO), a neurovascular protective agent, therapeutically supports angiogenesis after stroke by enhancing endogenous up-regulation of vascular endothelial growth factor (VEGF). Increased VEGF expression has been characterized to negatively impact the integrity of the blood brain barrier (BBB), causing brain edema and secondary injury. The present study investigated the rhEPO-induced BBB protection after stroke and how it might be achieved by affecting VEGF pathway. rhEPO treatment (5,000 U/kg, i.p., 30 min before stroke and once a day for three days after stroke) reduced Evans blue leakage and brain edema after ischemia. The expression of the BBB integrity markers, occludin, alpha-catenin and beta-catenin, in the brain was preserved in animals received rhEPO. rhEPO up-regulated VEGF expression; however, the expression of VEGF receptor-2 (fetal liver kinase receptor, Flk-1) was significantly reduced in rhEPO-treated animals three days after stroke. We propose that, disregarding increased VEGF levels, rhEPO protects against ischemia-induced BBB damage at least partly by down-regulating Flk-1 expression and the response to VEGF signaling in the acute phase after stroke.

Topics: Animals; Blood-Brain Barrier; Brain Edema; Cerebrovascular Circulation; Down-Regulation; Erythropoietin; Evans Blue; Fluorescent Antibody Technique; Infarction, Middle Cerebral Artery; Ischemic Attack, Transient; Male; Membrane Proteins; Mice; Microscopy, Confocal; Occludin; Recombinant Proteins; Stroke; Vascular Endothelial Growth Factor Receptor-2

Recombinant human erythropoietin (rhEPO; Epoetin-alpha; PROCRITtrade mark) has been shown to exert neuroprotective and restorative effects in a variety of CNS injury models. However, limited information is available regarding the dose levels required for these beneficial effects or the neuronal responses that may underlie them. Here we have investigated the dose-response to rhEPO and compared the effects of rhEPO with those of carbamylated rhEPO (CEPO) in a model of cerebral stroke in rats.. Rats subjected to embolic middle cerebral artery occlusion (MCAo) were treated with rhEPO or CEPO, starting at 6 h and repeated at 24 and 48 h, after MCAo. Cerebral infarct volumes were assessed at 28 days and neurological impairment at 7, 14, 21 and 28 days, post-MCAo.. rhEPO at dose levels of 500, 1150 or 5000 IU kg(-1) or CEPO at a dose level of 50 microg kg(-1) significantly reduced cortical infarct volume and reduced neurologic impairment. All doses of rhEPO, but not CEPO, produced a transient increase in haematocrit, while rhEPO and CEPO substantially reduced the number of apoptotic cells and activated microglia in the ischemic boundary region.. These data indicate that rhEPO and CEPO have anti-inflammatory and anti-apoptotic effects, even with administration at 6 h following embolic MCAo in rats. Taken together, these actions of rhEPO and CEPO are likely to contribute to their reduction of neurologic impairment following cerebral ischemia.

Topics: Animals; Apoptosis; Blood-Brain Barrier; Brain Ischemia; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Epoetin Alfa; Erythropoietin; Hematinics; Hematocrit; Infarction, Middle Cerebral Artery; Male; Microglia; Neuroprotective Agents; Rats; Rats, Wistar; Recombinant Proteins; Stroke

The administration of CD34-positive cells after stroke has been shown to have a beneficial effect on functional recovery by accelerating angiogenesis and neurogenesis in rodent models. Granulocyte colony-stimulating factor (G-CSF) is known to mobilize CD34-positive cells from bone marrow and has displayed neuroprotective properties after transient ischemic stress. This led us to investigate the effects of G-CSF administration after stroke in mouse. We utilized permanent ligation of the M1 distal portion of the left middle cerebral artery to develop a reproducible focal cerebral ischemia model in CB-17 mice. Animals treated with G-CSF displayed cortical atrophy and impaired behavioral function compared with controls. The negative effect of G-CSF on outcome was associated with G-CSF induction of an exaggerated inflammatory response, based on infiltration of the peri-infarction area with CD11b-positive and F4/80-positive cells. Although clinical trials with G-CSF have been started for the treatment of myocardial and limb ischemia, our results indicate that caution should be exercised in applying these results to cerebral ischemia.

Topics: Animals; Atrophy; Brain Ischemia; Data Interpretation, Statistical; Erythropoietin; Granulocyte Colony-Stimulating Factor; Immunohistochemistry; Mice; Middle Cerebral Artery; Necrosis; Neovascularization, Pathologic; Recombinant Proteins; Stroke; Treatment Outcome

Neonatal stroke leads to mortality and severe morbidity, but there is no effective treatment currently available. Erythropoietin (EPO) has been shown to promote cytoprotection and neurogenesis and decrease subventricular zone morphologic changes following brain injury. The long-term cellular response to EPO has not been defined, and local changes in cell fate decision may play a role in functional improvement. We performed middle cerebral artery occlusion in P10 rats. EPO treatment (5 U/g i.p.) significantly preserved hemispheric brain volume 6 weeks after injury. Furthermore, EPO increased the percentage of newly generated neurons while decreasing newly generated astrocytes following brain injury, without demonstrating long-term differences in the subventricular zone. These results suggest that EPO may neuroprotect and direct cell fate toward neurogenesis and away from gliogenesis in neonatal stroke.

Topics: Animals; Animals, Newborn; Astrocytes; Cell Differentiation; Cell Proliferation; Erythropoietin; Gliosis; Hypoxia, Brain; Infarction, Middle Cerebral Artery; Nerve Regeneration; Neurons; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Recovery of Function; Stem Cells; Stroke; Time; Treatment Outcome

Recently, we reported that erythropoietin attenuates neonatal brain injury caused by focal cerebral ischemia. The long-term effects of erythropoietin on focal cerebral ischemia-induced injury to the developing brain and the potential gender differences in these long-term effects have not been studied in detail. The current study demonstrated a similarity in the mean infarct volume in both the vehicle-treated male and female rats at 6 and 12 weeks after focal cerebral ischemia. On the other hand, erythropoietin treatment (1000 U/kg x three doses after focal cerebral ischemia) caused a significant reduction in the mean infarct volume in both males and females at 6 weeks after focal cerebral ischemia when compared with the corresponding vehicle-treated animals (males: 141.4+/-48.2 mm3 vs. 194.0+/-59.2 mm3, P<0.05; females: 85.4+/-31.6 mm3 vs. 183.4+/-46.3 mm3, P<0.05). Interestingly, the reduction in the mean infarct volume in the erythropoietin-treated males was significantly less than that in the erythropoietin-treated females at 6 weeks after focal cerebral ischemia (141.4+/-48.2 mm3 vs. 85.4+/-31.6 mm3, P<0.05). At 12 weeks after focal cerebral ischemia, the mean infarct volume in the erythropoietin-treated males significantly increased to 181.0+/-50.4 mm3 (P<0.05). In contrast, the mean infarct volume in the erythropoietin-treated females remained stable (87.0+/-41.7 mm3). Additionally, erythropoietin treatment significantly improved sensorimotor function recovery with a misstep number similar to the sham-operation group at 6 and 12 weeks after focal cerebral ischemia. Moreover, the mean number of missteps in the erythropoietin-treated females was less than that in males at 6 (13.5+/-2.0 vs. 24.5+/-2.5, P<0.05) and 12 (12.5+/-2.0 vs. 20.0+/-2.0, P<0.05) weeks after focal cerebral ischemia. These results indicate that erythropoietin administration after focal cerebral ischemia produces a significant long-term neuroprotective benefit on the developing brain, and that this effect is more beneficial in the female rats.

Topics: Animals; Animals, Newborn; Brain; Erythropoietin; Female; Humans; Male; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Sex Factors; Stroke

Treatment with erythropoietin and AT1 blockers is protective in experimental acute cerebral ischemia, with promising results in pilot clinical studies in human stroke. This paper examines the effects of using both agents as combination therapy in acute ischemic stroke.. We used the single carotid ligation stroke model in the gerbil. Six groups of 50 gerbils were treated either with placebo, erythropoietin (intraperitoneally, 5000 IU/kg, 2 and 48 h after stroke), olmesartan (10 mg/kg per day in drinking water started 36 h after stroke), ramipril (2.5 mg/kg per day in drinking water started 36 h after stroke), erythropoietin + olmesartan, or erythropoietin + ramipril. Long-term (1 month) Kaplan-Meyer survival curves were obtained, and survivors were submitted at day 30 to immediate (object recognition test) and spatial (Morris water maze) memory function tests.. Erythropoietin alone and olmesartan alone, but not ramipril, significantly increased survival at day 30 compared with untreated controls (38, 30 and 6% versus 12%, respectively). Combined treatment with erythropoietin and olmesartan further increased the survival rate to 56%, whereas combined therapy with erythropoietin and ramipril decreased 30-day survival to 24% (P < 0.0001, erythropoietin + olmesartan versus erythropoietin + ramipril). Untreated stroke survivors had markedly altered performances in both the object recognition test (P = 0.0007) and the Morris water maze (P < 0.0001) tests at day 30 compared with normal gerbils. In erythropoietin-treated animals, ramipril therapy had no beneficial effect whereas olmesartan fully restored normal response to the memory tests.. Post-infarct treatment with olmesartan combined with early erythropoietin therapy has a protective effect on survival, and markedly improves long-term memory dysfunction in this experimental model.

Topics: Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Animals; Disease Models, Animal; Drug Therapy, Combination; Erythropoietin; Gerbillinae; Imidazoles; Kaplan-Meier Estimate; Male; Memory Disorders; Neuroprotective Agents; Ramipril; Recombinant Proteins; Stroke; Tetrazoles

Neonatal stroke is a condition that leads to disability in later life, and as yet there is no effective treatment. Recently, erythropoietin (EPO) has been shown to be cytoprotective following brain injury and may promote neurogenesis. However, the effect of EPO on functional outcome and on morphologic changes in neonatal subventricular zone (SVZ) following experimental neonatal stroke has not been described. We used a transient focal model of neonatal stroke in P10 rat. Injury was documented by diffusion weighted MRI during occlusion. Immediately upon reperfusion, either EPO (5U/gm) or vehicle was administered intraperitoneally and animals were allowed to grow for 2 wk. Sensorimotor function was assessed using the cylinder rearing test and then brains were processed for volumetric analysis of the SVZ. Stroke induced SVZ expansion proportional to hemispheric volume loss. EPO treatment markedly preserved hemispheric volume and decreased the expansion of SVZ unilaterally. Furthermore, EPO treatment significantly improved the asymmetry of forelimb use following neonatal stroke. This functional improvement directly correlated with the amount of preserved hemispheric volume. These results suggest EPO may be a candidate in the treatment of neonatal stroke.

Topics: Animals; Animals, Newborn; Behavior, Animal; Benzoxazines; Brain; Brain Injuries; Coloring Agents; Diffusion; Erythropoietin; Hypoxia-Ischemia, Brain; Magnetic Resonance Imaging; Neurons; Oxazines; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Reperfusion Injury; Stroke; Time Factors; Treatment Outcome

Brain injury evolves over time, often taking days or even weeks to fully develop. It is a dynamic process that involves immediate oxidative stress and excitotoxicity followed by inflammation and preprogrammed cell death. This article presents a brief overview of mechanisms of neuroprotection in the developing brain. Although the focus is on ischemic injury, the conclusions drawn apply to any type of brain insult-epileptic seizures, trauma, or ischemia. Strategies of neuroprotection include salvaging neurons through the use of targeted pharmacotherapies, protecting neurons through preconditioning, and repairing neurons by enhancing neurogenesis. Drug therapies that dampen the impact of immediate and downstream postinjury events are only modestly effective in protecting the brain from ischemic injury. In experimental models, complete or true protection can be achieved only through preconditioning, a process during which an animal develops tolerance to an otherwise lethal stressor. Although of no clinical use, preconditioning models have provided valuable insight into how repair systems work in the brain. Cumulative evidence indicates that the same genes that are upregulated during preconditioning, those mediating true protection, are also upregulated during injury and repair. Specifically, hypoxic preconditioning and hypoxic-ischemic insult have been shown to induce hypoxia inducible factor-1 (HIF-1) and its target survival genes, vascular endothelial growth factor (VEGF), and erythropoietin (Epo) in rodents. Of particular interest is the upregulation of Epo, a growth factor that may have therapeutic potential in the treatment of ischemic stroke. At this time, however, the postinjury enhancement of neurogenesis appears to offer the best hope for long-lasting functional recovery following brain injury.

Topics: Animals; Apoptosis; Brain; Brain Ischemia; Disease Models, Animal; Epilepsy; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Ischemic Preconditioning; Neuronal Plasticity; Neurons; Neuroprotective Agents; Oxidative Stress; Stroke; Up-Regulation

Erythropoietin (EPO) promotes proliferation and differentiation of erythroid progenitors and the survival of maturing erythroid cells. Here, we investigated the role of EPO in brain repair after stroke.. Rats were treated with recombinant human EPO (rhEPO) at 24 hours after the onset of embolic stroke. An array of behavior tests was performed. Rats were euthanized 28 days after stroke for measurements of infarct volume, angiogenesis, and neurogenesis. In vitro, neurospheres derived from the subventricular zone (SVZ) of the rat and cerebral endothelial cells derived from the mouse were treated with rhEPO. Capillary-like tube formation and neuronal differentiation were measured.. Treatment with rhEPO significantly improved functional recovery, along with increases in density of cerebral microvessels at the stroke boundary and numbers of BrdU, doublecortin, and nestin immunoreactive cells in the SVZ. rhEPO treatment significantly increased brain levels of vascular endothelial growth factor (VEGF) and brain-derived neurotrophic factor (BDNF). In vitro, rhEPO enhanced capillary tube formation of cerebral endothelial cells, which was inhibited by a specific VEGF receptor 2 antagonist (SU1498). Incubation of neurospheres derived from stroke SVZ with anti-EPO neutralizing antibody inhibited neurogenesis, whereas incubation of stroke-derived neurospheres with rhEPO enhanced neurogenesis.. Our data suggest that EPO-increased VEGF and BDNF may be involved in angiogenesis and neurogenesis, which could contribute to functional recovery.

Topics: Angiogenesis Inducing Agents; Animals; Brain; Brain-Derived Neurotrophic Factor; Doublecortin Protein; Erythropoietin; Infarction, Middle Cerebral Artery; Male; Microcirculation; Models, Animal; Neovascularization, Physiologic; Nerve Regeneration; Neuronal Plasticity; Rats; Rats, Wistar; Recombinant Proteins; Stroke; Vascular Endothelial Growth Factor A

Systemic hypoxia is a common complication in stroke patients and may exacerbate ischemic brain damage. Expression of the hypoxia-inducible cytokine erythropoietin (Epo) is upregulated in the brain in both stroke patients and in animal stroke models and exerts local neuroprotective effects in the ischemic brain. Epo is also well known to stimulate red blood cell (RBC) production. The purpose of the present study was to evaluate whether poststroke systemic hypoxia is present in the rat model and whether it is associated with increased peripheral Epo and RBC production.. Wistar rats underwent 1-hour transient middle cerebral artery occlusion (MCAO) under mechanical ventilation, followed by reperfusion without further ventilation. Groups of MCAO and sham-operated animals were evaluated at extended times after reperfusion for assessment of arterial blood gases, plasma Epo, and complete blood count.. Arterial oxygen saturation was significantly lower in the infarct group between 6 and 24 hours after reperfusion (P=0.0005), and plasma Epo levels were increased 6 hours after reperfusion (P<0.05). RBC counts and hematocrit were transiently increased 2 to 7 days after reperfusion in animals with MCAO compared with sham. Maximal increases were seen at day 7 (22% and 16% increases of RBC count and hematocrit, respectively; P<0.001). In contrast, the white blood cell counts in animals with MCAO decreased by >30% in the same time period.. Plasma Epo levels, RBC counts, and hematocrit are all increased in response to systemic hypoxia after cerebral ischemia in rats.

Topics: Animals; Disease Models, Animal; Erythrocyte Count; Erythropoiesis; Erythropoietin; Hematocrit; Homeostasis; Hypoxia; Infarction, Middle Cerebral Artery; Male; Oxygen; Rats; Rats, Wistar; Stroke

Topics: Animals; Clinical Trials as Topic; Drug Design; Erythropoietin; Humans; Ligands; Mental Disorders; Nervous System Diseases; Neuroprotective Agents; Receptors, Erythropoietin; Recombinant Proteins; Stroke

Erythropoietin (EPO) is both hematopoietic and tissue protective, putatively through interaction with different receptors. We generated receptor subtype-selective ligands allowing the separation of EPO's bioactivities at the cellular level and in animals. Carbamylated EPO (CEPO) or certain EPO mutants did not bind to the classical EPO receptor (EPOR) and did not show any hematopoietic activity in human cell signaling assays or upon chronic dosing in different animal species. Nevertheless, CEPO and various nonhematopoietic mutants were cytoprotective in vitro and conferred neuroprotection against stroke, spinal cord compression, diabetic neuropathy, and experimental autoimmune encephalomyelitis at a potency and efficacy comparable to EPO.

Topics: Animals; Apoptosis; Binding Sites; Cells, Cultured; Diabetic Neuropathies; Drug Design; Encephalomyelitis, Autoimmune, Experimental; Erythropoiesis; Erythropoietin; Female; Hematocrit; Humans; Ligands; Mice; Mice, Inbred C3H; Mutagenesis; Nervous System Diseases; Neurons; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Receptors, Erythropoietin; Recombinant Proteins; Signal Transduction; Spinal Cord Compression; Stroke; Structure-Activity Relationship

Topics: Erythropoietin; Glutamic Acid; Humans; Neurons; Stroke

Topics: Aged; Clinical Trials as Topic; Emergencies; Erythropoietin; Fibrinolytic Agents; Germany; Humans; Intensive Care Units; Multicenter Studies as Topic; Placebos; Plasminogen Activators; Stroke; Thrombolytic Therapy

Cellular response to hypoxia is mainly controlled by hypoxia-inducible factor 1 (HIF-1). The HIF-1 target gene erythropoietin (EPO) has been described as neuroprotective. Thus, we hypothesize EPO to be an essential mediator of protection in hypoxic preconditioning.. We randomized Sv129 mice into groups for different pretreatments, different hypoxia-ischemia intervals, or different durations of ischemia. For hypoxic preconditioning, the animals were exposed to a hypoxic gas mixture (8% O2 and 92% N2) for 30, 60, 180, 300, or 360 minutes. At 0, 24, 48, 72, or 144 hours later, we performed middle cerebral artery occlusion and allowed reperfusion after 30, 45, 60, or 120 minutes, or occlusion was left to be permanent. We studied EPO gene expression in brain tissue with a real-time reverse transcriptase-polymerase chain reaction and measured HIF-1 DNA-binding activity with an electrophoretic mobility shift assay. To block endogenously produced EPO, we instilled soluble EPO receptor into the cerebral ventricle.. Hypoxic preconditioning for 180 or 300 minutes induced relative tolerance to transient focal cerebral ischemia, as evidenced by a reduction of infarct volumes to 75% or 54% of the control, respectively. Hypoxic pretreatment was effective only when applied 48 or 72 hours before middle cerebral artery occlusion. Sixty minutes after hypoxia, we found a marked activation of HIF-1 DNA-binding activity and a 7-fold induction of EPO transcription. Infusion of soluble EPO receptor significantly reduced the protective effect of hypoxic pretreatment by 40%.. Endogenously produced EPO is an essential mediator of ischemic preconditioning.

Topics: Animals; Brain; Cerebral Infarction; Disease Models, Animal; DNA; DNA-Binding Proteins; Electrophoretic Mobility Shift Assay; Erythropoietin; Female; Hippocampus; Hypoxia; Hypoxia-Inducible Factor 1; Hypoxia-Inducible Factor 1, alpha Subunit; Infarction, Middle Cerebral Artery; Injections, Intraventricular; Ischemic Preconditioning; Male; Mice; Mice, Inbred Strains; Nuclear Proteins; Receptors, Erythropoietin; Reperfusion; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Stroke; Time Factors; Transcription Factors

Topics: Erythropoietin; Humans; Recombinant Proteins; Stroke