losartan-potassium and Hypoxia-Ischemia--Brain

Previous systematic review has shown the safety and efficiency of EPO (erythropoietin) for neonatal hypoxic-ischemic encephalopathy (HIE). To date, the evidence is limited that EPO is beneficial to therapeutic hypothermia as an adjuvant. There has not a brief discussion about the neuroprotection effects of EPO without hypothermia. To evaluate the long-term prognosis of HIE treated with EPO alone, we carried out this study that can be a supplement to the previous meta-analysis.. 7 databases (including PubMed, EMBASE, Cochrane, CKNI, CBM, WanFang, and VIP) and the ClinicalTrials.gov were retrieved from inception to 1 March 2020. The inclusion criteria were RCTs with EPO treatment without hypothermia. The outcomes were tested by using the Bayley Scales of Infant Development (BSID), including the Bayley Mental Development Index Score (MDI) and the Bayley Psychomotor Development Index Score (PDI). This meta-analysis was done to compare the Risk Ratio (RR) for the scores of BSID less than 70 after over 6 months of follow-up.. 11 RCTs (1099 newborns) were included, excluding deaths and lost visits, and 917 patients finally were performed the statistical analysis. In neonatal HIE infants, investigation results showed a lower risk of cognitive impairment and psychomotor disability with EPO monotherapy. The pooled event rates of MDI <70 saw a reduction of 36% (95% CI 24%-54%) compared to the control group. There was a decrease of 37% (95% CI 24%-56%) of Psychomotor abnormal (PDI <70) in the EPO group.. EPO administration alone could improve the scores of mental and psychomotor in neonates with HIE. However, the level of evidence is low to moderate for the insufficient sample size, so large-scale, multicenter clinical trials are still needed.

Topics: Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Maternal Behavior; Neuroprotective Agents

We examined whether erythropoietin monotherapy improves neurodevelopmental outcomes in near-term and term infants with neonatal encephalopathy (NE) in low-middle income countries (LMICs).. We searched Pubmed, Embase, and Web of Science databases to identify studies that used erythropoietin (1500-12,500 units/kg/dose) or a derivative to treat NE.. Five studies, with a total of 348 infants in LMICs, were retrieved. However, only three of the five studies met the primary outcome of death or neuro-disability at 18 months of age or later. Erythropoietin reduced the risk of death (during the neonatal period and at follow-up) or neuro-disability at 18 months or later (p < 0.05). Death or neuro-disability occurred in 27.6% of the erythropoietin group and 49.7% of the comparison group (risk ratio 0.56 (95% CI: 0.42-0.75)).. The pooled data suggest that erythropoietin monotherapy may improve outcomes after NE in LMICs where therapeutic hypothermia is not available.

Topics: Developing Countries; Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant; Infant, Newborn; Neuroprotection

Neonatal encephalopathy (NE), most commonly a result of the disruption of cerebral oxygen delivery, is the leading cause of neurologic disability in term neonates. Given the key role of free radicals in brain injury development following hypoxia-ischemia-reperfusion, several oxidative biomarkers have been explored in preclinical and clinical models of NE. Among these, antioxidant enzyme activity, uric acid excretion, nitric oxide, malondialdehyde, and non-protein-bound iron have shown promising results as possible predictors of NE severity and outcome. Owing to high costs and technical complexity, however, their routine use in clinical practice is still limited. Several strategies aimed at reducing free radical production or upregulating physiological scavengers have been proposed for NE. Room-air resuscitation has proved to reduce oxidative stress following perinatal asphyxia and is now universally adopted. A number of medications endowed with antioxidant properties, such as melatonin, erythropoietin, allopurinol, or N-acetylcysteine, have also shown potential neuroprotective effects in perinatal asphyxia; nevertheless, further evidence is needed before these antioxidant approaches could be implemented as standard care.

Topics: Acetylcysteine; Allopurinol; Animals; Antioxidants; Asphyxia Neonatorum; Biomarkers; Brain Injuries; Clinical Trials as Topic; DNA; Erythropoietin; Free Radicals; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Malondialdehyde; Melatonin; Nitric Oxide; Oxidative Stress; Prostaglandins; Proteins; Uric Acid

Therapeutic hypothermia is now proven to reduce death or disability in term and near-term born infants with moderate to severe hypoxic-ischemic encephalopathy. Nevertheless, many infants still survive with disability, despite treatment with hypothermia. Recent preclinical and clinical studies suggest that current protocols for therapeutic hypothermia are near-optimal. The obvious strategy, in addition to improving early initiation of therapeutic hypothermia after birth, is to combine hypothermia with other neuroprotective agents. We review evidence that the mechanisms of action of many promising agents overlap with the anti-excitotoxic, anti-apoptotic, and anti-inflammatory mechanisms of hypothermia, leading to a lack of benefit from combination treatment. Moreover, even apparently beneficial combinations have failed to translate in clinical trials. These considerations highlight the need for preclinical studies to test clinically realistic protocols of timing and duration of treatment, before committing to large randomized controlled trials.

Topics: Combined Modality Therapy; Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Magnesium Sulfate; Neuroprotection; Neuroprotective Agents

Neonatal hypoxic-ischemic encephalopathy is a disorder with heterogeneous manifestation due to asphyxia during perinatal period. It affects approximately 3-12 children per 1000 live births and cause death of 1 million neonates worldwide per year. Besides, motor disabilities, seizures, impaired muscle tone and epilepsy are few of the consequences of hypoxic-ischemic encephalopathy. Despite an extensive research effort regarding various treatment strategies, therapeutic hypothermia with intensive care unit supportive treatment remains the only approved method for neonates who have suffered from moderate to severe hypoxic-ischemic encephalopathy. However, these protocols are only partially effective given that many infants still suffer from severe brain damage. Thus, further research to systematically test promising neuroprotective treatments in combination with hypothermia is essential. In this review, we discussed the pathophysiology of hypoxic-ischemic encephalopathy and delved into different promising treatment modalities, such as melatonin and erythropoietin. However, preclinical studies and clinical trials are still needed to further elucidate the mechanisms of action of these modalities.

Topics: Central Nervous System Depressants; Erythropoietin; Female; Humans; Hypoxia; Hypoxia-Ischemia, Brain; Infant, Newborn; Melatonin; Pregnancy

Neonatal hypoxic ischemic encephalopathy (HIE) is an important cause of neonatal death and disability. At present, there is no unified standard and specialized treatment method for neonatal HIE. In clinical practice, we have found that a gap remains between preclinical medical research and clinical application in the treatment of neonatal HIE. To promote an organic combination of preclinical research and clinical application, we propose the different phases as intervention targets, based on the pathophysiologic changes in phases I, II, and III of neonatal HIE; moreover, we suggest transformative medicine as a principle that may improve the therapeutic effect by blocking the progression of the disease to an irreversible stage. For instance, in phase I, mild hypothermia, free radical scavenger (erythropoietin, hydrogen-rich saline), excitatory amino acid receptor blocker, and neuroprotective agents should be administered to neonates with moderate/severe HIE; in phase II, following phase I treatment, anti-inflammatory agents, neuroprotective or nerve regeneration agents, and stem cell transplantation should be administered to patients; in phase III, anti-inflammatory agents, neuroprotective or nerve regeneration agents, and stem cell transplantation should be administered to patients. As soon as the patient's condition has stabilized, acupuncture, massage, and rehabilitation training should be performed. Following further study of stem cells, stem cell transplantation is expected to become the most promising therapeutic candidate for treatment of severe neonatal HIE with its sequelae.

Topics: Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Neuroprotective Agents; Stem Cell Transplantation

Background Erythropoietin (EPO) appears to confer neuroprotection to the injured brain. Randomized clinical trials (RCTs) have demonstrated its safety in neonates with hypoxic-ischemic encephalopathy (HIE); however, the evidence is unclear. The objective of this study was to examine the role of EPO in perinatal HIE by a systematic review and meta-analysis. Methods Database search included Embase, MEDLINE, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Cochrane Central Register of Controlled Trials (CENTRAL). RCTs reporting a death, neurodevelopmental outcomes or brain injury were included. Two authors extracted the data independently from included studies and assessed the level of evidence (LOE). Results Six RCTs (EPO=5 and darbepoetin α=1) involving 454 neonates were included. A trend toward a lower risk of death was identified in infants treated with EPO [EPO with or without hypothermia: five RCTs, 368 participants, relative risk (RR) 0.74, 95% confidence interval (CI) 0.47-1.19, LOE-low; EPO without hypothermia: four RCTs, 318 participants, RR 0.89, 95% CI 0.49-1.32, LOE-low]. EPO treatment without hypothermia compared to placebo resulted in a reduced risk of cerebral palsy (two RCTs, 230 participants, RR 0.47, 95% CI 0.27-0.80, LOE-moderate) and moderate to severe cognitive impairment (two RCTs, 226 participants, RR 0.49, 95% CI 0.28-0.85, LOE-moderate). A reduced risk of brain injury was identified in EPO treated infants (EPO with or without hypothermia, two RCTs, 148 participants, RR 0.70, 95% CI 0.53-0.92, LOE-moderate). Conclusion EPO administration in neonates with perinatal HIE reduces the risk of brain injury, cerebral palsy and cognitive impairment. The evidence is limited to suggest its role as an adjuvant to hypothermia. Larger powered trials are underway to overcome this limitation.

Topics: Brain Injuries; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Infant, Premature; Neurodevelopmental Disorders

Perinatal asphyxia is characterized by oxygen deprivation and lack of perfusion in the perinatal period, leading to hypoxic-ischemic encephalopathy and sequelae such as cerebral palsy, mental retardation, cerebral visual impairment, epilepsy and learning disabilities. On cellular level PA is associated with a decrease in oxygen and glucose leading to ATP depletion and a compromised mitochondrial function. Upon reoxygenation and reperfusion, the renewed availability of oxygen gives rise to not only restoration of cell function, but also to the activation of multiple detrimental biochemical pathways, leading to secondary energy failure and ultimately, cell death. The formation of reactive oxygen species, nitric oxide and peroxynitrite plays a central role in the development of subsequent neurological damage. In this review we give insight into the pathophysiology of perinatal asphyxia, discuss its clinical relevance and summarize current neuroprotective strategies related to therapeutic hypothermia, ischemic postconditioning and pharmacological interventions. The review will also focus on the possible neuroprotective actions and molecular mechanisms of the selective neuronal and inducible nitric oxide synthase inhibitor 2-iminobiotin that may represent a novel therapeutic agent for the treatment of hypoxic-ischemic encephalopathy, both in combination with therapeutic hypothermia in middle- and high-income countries, as well as stand-alone treatment in low-income countries.

Topics: Allopurinol; Asphyxia Neonatorum; Biotin; Cerebral Palsy; Clinical Trials as Topic; Epilepsy; Erythropoietin; Female; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Intellectual Disability; Ischemic Postconditioning; Melatonin; Neuroprotective Agents; Pregnancy; Reactive Nitrogen Species; Reactive Oxygen Species

Neonatal brain injury (NBI) remains a major contributor to neonatal mortality and long-term neurodevelopmental morbidity. Although therapeutic hypothermia is the only proven treatment to minimize brain injury caused by neonatal encephalopathy in term neonates, it provides incomplete neuroprotection. There are no specific drugs yet proven to prevent NBI in preterm neonates. This review discusses the scientific and emerging clinical trial data for several neuroprotective drugs in development, examining potential efficacy and safety concerns. Drugs with the highest likelihood of success and closest to clinical application include erythropoietin for term and preterm neonates and antenatal magnesium for preterm neonates.

Topics: Adrenal Cortex Hormones; Allopurinol; Anesthetics, Inhalation; Anticonvulsants; Antioxidants; Cerebral Intraventricular Hemorrhage; Cyclooxygenase Inhibitors; Darbepoetin alfa; Erythropoietin; Free Radical Scavengers; Hematinics; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Indomethacin; Infant, Newborn; Leukomalacia, Periventricular; Magnesium; Melatonin; Neuroprotection; Prenatal Care; Topiramate; Xenon

Perinatal asphyxia-induced brain injury may present as hypoxic-ischemic encephalopathy in the neonatal period, and disability including cerebral palsy in the long term. The brain injury is secondary to both the hypoxic-ischemic event and the reoxygenation-reperfusion following resuscitation. Early events in the cascade of brain injury can be classified as either inflammation or oxidative stress through the generation of free radicals. The objective of this paper is to present efforts that have been made to limit the oxidative stress associated with hypoxic-ischemic encephalopathy. In the acute phase of ischemia/hypoxia and reperfusion/reoxygenation, the outcomes of asphyxiated infants can be improved by optimizing the initial delivery room stabilization. Interventions include limiting oxygen exposure, and shortening the time to return of spontaneous circulation through improved methods for supporting hemodynamics and ventilation. Allopurinol, melatonin, noble gases such as xenon and argon, and magnesium administration also target the acute injury phase. Therapeutic hypothermia, N-acetylcysteine2-iminobiotin, remote ischemic postconditioning, cannabinoids and doxycycline target the subacute phase. Erythropoietin, mesenchymal stem cells, topiramate and memantine could potentially limit injury in the repair phase after asphyxia. To limit the injurious biochemical processes during the different stages of brain injury, determination of the stage of injury in any particular infant remains essential. Currently, therapeutic hypothermia is the only established treatment in the subacute phase of asphyxia-induced brain injury. The effects and side effects of oxidative stress reducing/limiting medications may however be difficult to predict in infants during therapeutic hypothermia. Future neuroprotection in asphyxiated infants may indeed include a combination of therapies. Challenges include timing, dosing and administration route for each neuroprotectant.

Topics: Acetylcysteine; Allopurinol; Argon; Asphyxia Neonatorum; Cannabinoids; Erythropoietin; Female; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Magnesium Sulfate; Melatonin; Neuroprotective Agents; Oxidative Stress; Pregnancy; Treatment Outcome; Xenon

Hypoxic ischemic encephalopathy (HIE) is one of the leading causes of neonatal mortality in developing countries and leads to some form of neuro-developmental disability in latter part of life.. The aim of this study is to evaluate the role of erythropoietin (EPO) in neuroprotection for term newborn having HIE.. The literature search was done for various trials by searching the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, Web of science, Scopus, Index Copernicus, and other database.. A total of nine studies fulfilled inclusion criteria. EPO has shown to cause reduction in death and disability, better long-term neuro-developmental outcome, improvement in EEG, and reduction in risk of cerebral palsy.. EPO treatment has neuroprotective effects against moderate/severe HIE and improves long-term behavioral neurological developments in neonates.

Topics: Asphyxia Neonatorum; Cerebral Palsy; Developmental Disabilities; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Neuroprotective Agents; Randomized Controlled Trials as Topic; Term Birth; Treatment Outcome

Hypoxic ischemic encephalopathy (HIE) is the most important reason for morbidity and mortality in term-born infants. Understanding pathophysiology of the brain damage is essential for the early detection of patients with high risk for HIE and development of strategies for their treatments. Areas covered: This review discusses pathophysiology of the neonatal HIE and its treatment options, including hypothermia, melatonin, allopurinol, topiramate, erythropoietin, N-acetylcyctein, magnesium sulphate and xenon. Expert commentary: Several clinical studies have been performed in order to decrease the risk of brain injury due to difficulties in the early diagnosis and treatment, and to develop strategies for better long-term outcomes. Although currently standard treatment methods include therapeutic hypothermia for neonates with moderate to severe HIE, new supportive options are needed to enhance neuroprotective effects of the hypothermia, which should aim to reduce production of the free radicals and to have anti-inflammatory and anti-apoptotic actions.

Topics: Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Neuroprotective Agents

Neonatal encephalopathy (NE) is a major cause of neonatal mortality and morbidity. Therapeutic hypothermia (TH) is standard treatment for newborns at 36 weeks of gestation or greater with intrapartum hypoxia-related NE. Term and late preterm infants with moderate to severe encephalopathy show improved survival and neurodevelopmental outcomes at 18 months of age after TH. TH can increase survival without increasing major disability, rates of an IQ less than 70, or cerebral palsy. Neonates with severe NE remain at risk of death or severe neurodevelopmental impairment. This review discusses the evidence supporting TH for term or near term neonates with NE.

Topics: Anesthetics, Inhalation; Biotin; Central Nervous System Depressants; Cerebral Palsy; Constriction; Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Intellectual Disability; Melatonin; Stem Cell Transplantation; Survival Rate; Umbilical Cord; Xenon

Perinatal hypoxic-ischaemic encephalopathy (HIE) occurs in 1 to 3 per 1000 term births. HIE is not preventable in most cases, and therapies are limited. Hypothermia improves outcomes and is the current standard of care. Yet, clinical trials suggest that 44-53% of infants who receive hypothermia will die or suffer moderate to severe neurological disability. In this article, we review the preclinical and clinical evidence for erythropoietin (EPO) as a potential novel neuroprotective agent for the treatment of HIE. EPO is a novel neuroprotective agent, with remarkable neuroprotective and neuroregenerative effects in animals. Rodent and primate models of neonatal brain injury support the safety and efficacy of multiple EPO doses for improving histological and functional outcomes after hypoxia-ischaemia. Small clinical trials of EPO in neonates with HIE have also provided evidence supporting safety and preliminary efficacy in humans. There is currently insufficient evidence to support the use of high-dose EPO in newborns with HIE. However, several on-going trials will provide much needed data regarding the safety and efficacy of this potential new therapy when given in conjunction with hypothermia for HIE. Novel neuroprotective therapies are needed to further reduce the rate and severity of neurodevelopmental disabilities resulting from HIE. High-dose EPO is a promising therapy that can be administered in conjunction with hypothermia. However, additional data are needed to determine the safety and efficacy of this adjuvant therapy for HIE.

Topics: Animals; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Neuroprotective Agents

Intrapartum-related events are the third leading cause of childhood mortality worldwide and result in one million neurodisabled survivors each year. Infants exposed to a perinatal insult typically present with neonatal encephalopathy (NE). The contribution of pure hypoxia-ischaemia (HI) to NE has been debated; over the last decade, the sensitising effect of inflammation in the aetiology of NE and neurodisability is recognised. Therapeutic hypothermia is standard care for NE in high-income countries; however, its benefit in encephalopathic babies with sepsis or in those born following chorioamnionitis is unclear. It is now recognised that the phases of brain injury extend into a tertiary phase, which lasts for weeks to years after the initial insult and opens up new possibilities for therapy.There has been a recent focus on understanding endogenous neuroprotection and how to boost it or to supplement its effectors therapeutically once damage to the brain has occurred as in NE. In this review, we focus on strategies that can augment the body's own endogenous neuroprotection. We discuss in particular remote ischaemic postconditioning whereby endogenous brain tolerance can be activated through hypoxia/reperfusion stimuli started immediately after the index hypoxic-ischaemic insult. Therapeutic hypothermia, melatonin, erythropoietin and cannabinoids are examples of ways we can supplement the endogenous response to HI to obtain its full neuroprotective potential. Achieving the correct balance of interventions at the correct time in relation to the nature and stage of injury will be a significant challenge in the next decade.

Topics: Asphyxia Neonatorum; Brain; Cannabinoids; Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Melatonin; Neuroprotection; Neuroprotective Agents

Certain groups of neonates are at high risk of developing long-term neurodevelopmental impairment and might be considered candidates for neuroprotective interventions. This article explores some of these high-risk groups, relevant mechanisms of brain injury, and specific mechanisms of cellular injury and death. The potential of erythropoietin (Epo) to act as a neuroprotective agent for neonatal brain injury is discussed. Clinical trials of Epo neuroprotection in preterm and term infants are updated.

Topics: Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Neuroprotection

This article explains the mechanisms underlying choices of pharmacotherapy for hypoxic-ischemic insults of both preterm and term babies. Some preclinical data are strong enough that clinical trials are now underway. Challenges remain in deciding the best combination therapies for each age and insult.

Topics: Acetylcysteine; Allopurinol; Antioxidants; Ascorbic Acid; Biopterins; Erythropoietin; Excitatory Amino Acid Antagonists; Free Radical Scavengers; Fructose; Humans; Hypoxia-Ischemia, Brain; Infant, Extremely Premature; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Melatonin; Memantine; Neuroprotective Agents; Nitric Oxide Synthase Type III; Resveratrol; Stilbenes; Topiramate; Vitamin E; Xenon

The use of erythropoiesis-stimulating agents (ESAs) such as erythropoietin and darbepoetin in preterm and term infants has been studied for over 20 years. Recent investigations have explored the potential neuroprotective effects of ESAs. We review the recent clinical trials and experimental animal models that provide evidence in support of using ESA to improve the neurodevelopmental outcomes in term and preterm infants.. Continued work using animal models have confirmed the neuroprotective properties of ESAs, including promotion of oligodendrocyte development in the face of neuronal injury. Clinical studies in term and preterm infants have reported the neuroprotective effects following ESA administration, and improved neurodevelopmental outcomes have been reported in the studies of preterm infants.. ESAs show great promise in preventing and treating brain injury in term and preterm infants.

Topics: Animals; Child Development; Darbepoetin alfa; Drug Administration Schedule; Erythropoietin; Hematinics; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Infant, Premature; Neuroprotective Agents

This review summarizes target populations of neonates for which erythropoietin (Epo) neuroprotective therapy might be of benefit, and the mechanisms by which Epo functions as a neuroprotective agent. Potential risks of Epo are reviewed. Finally, the progression of Epo neuroprotection from preclinical studies to translational studies is discussed.

Topics: Brain; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Infant, Newborn, Diseases; Infant, Premature, Diseases; Nervous System Diseases; Neuroprotective Agents; Risk Factors

Neonatal brain injury, caused by perinatal hypoxia-ischemia and extreme prematurity, remains a great challenge for prevention and treatment. There is no effective treatment for term hypoxic-ischemic encephalopathy (HIE) except hypothermia which by itself does not afford complete neuroprotection. Erythropoietin (EPO), a pleiotropic cytokine, has neuroprotective effects in a series of neonatal experimental models and recent clinical trials of HIE. However, the mechanisms, dosing, and the toxicity of EPO in these settings are inconsistently reported. This review will focus on the possible mechanisms, recent clinical advances and potential complications of EPO used in research and the clinic. In addition, optimal dose and administrative routes of EPO, and novel EPO mimetics will be discussed.

Topics: Brain Injuries; Clinical Trials as Topic; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Infant, Newborn, Diseases; Neuroprotective Agents; Receptors, Erythropoietin; Signal Transduction

Erythropoientin (Epo), a glycoprotein hormone, plays an important role in erythropoiesis and neuroprotection. Recently,Epo is also considered to have protective effects against hyperoxic lung injury, retinopathy of prematurity and neonatal necrotizing enterocolitis. Recombinant human erythropietin (rhEpo) as Epo gene cloning drug has been widely used in neonatal clinical practice.

Topics: Enterocolitis, Necrotizing; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Infant, Newborn, Diseases; Recombinant Proteins; Retinopathy of Prematurity

Perinatal asphyxia, intraventricular hemorrhage and stroke are common causes of neonatal brain injury, with hypoxia-ischemia as the final common pathway of injury. Erythropoietin (Epo) has potential to lessen neurologic sequelae due to hypoxia-ischemia. The purpose of this review is to highlight new clinical trials and experimental evidence that expand our understanding of Epo as a potential treatment for perinatal brain injury.. Several trials of Epo treatment are reviewed: two phase I/II trials of high-dose Epo given to preterm infants established pharmacokinetic and safety profiles, and a trial of Epo treatment for term infants with moderate hypoxic-ischemic encephalopathy found reduced disability. Potential risks and benefits of high-dose Epo are discussed. New evidence related to Epo receptor expression, signal transduction pathways, and mechanisms of neuroprotection are reviewed.. Cautious optimism is warranted regarding the use of high-dose Epo as a treatment option for neonatal brain injury. To date, Epo has been well tolerated to use in neonatal populations and now studies of neuroprotective efficacy are underway.

Topics: Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Infant, Premature

Neuroprotection is a major health care priority, given the enormous burden of human suffering and financial cost caused by perinatal brain damage. With the advent of hypothermia as therapy for term hypoxic-ischemic encephalopathy, there is hope for repair and protection of the brain after a profound neonatal insult. However, it is clear from the published clinical trials and animal studies that hypothermia alone will not provide complete protection or stimulate the repair that is necessary for normal neurodevelopmental outcome. This review critically discusses drugs used to treat seizures after hypoxia-ischemia in the neonate with attention to evidence of possible synergies for therapy. In addition, other agents such as xenon, N-acetylcysteine, erythropoietin, melatonin and cannabinoids are discussed as future potential therapeutic agents that might augment protection from hypothermia. Finally, compounds that might damage the developing brain or counteract the neuroprotective effects of hypothermia are discussed.

Topics: Acetylcysteine; Anticonvulsants; Body Temperature; Cannabinoids; Combined Modality Therapy; Erythropoietin; Fructose; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Levetiracetam; Melatonin; Neuroprotective Agents; Piracetam; Topiramate; Xenon

Perinatal hypoxic-ischemic encephalopathy can be a devastating complication of childbirth. Herein, the authors review the pathophysiology of hypoxic-ischemic encephalopathy and the current status of neuroprotective strategies to ameliorate the injury centering on four themes: (1) monitoring in the perinatal period, (2) rapid identification of affected neonates to allow timely institution of therapy, (3) preconditioning therapy (a therapeutic that reduces the brain vulnerability) before hypoxic-ischemic encephalopathy, and (4) prompt institution of postinsult therapies to ameliorate the evolving injury. Recent clinical trials have demonstrated the significant benefit for hypothermic therapy in the postnatal period; furthermore, there is accumulating preclinical evidence that adjunctive therapies can enhance hypothermic neuroprotection. Advances in the understanding of preconditioning may lead to the administration of neuroprotective agents earlier during childbirth. Although most of these neuroprotective strategies have not yet entered clinical practice, there is a significant hope that further developments will enhance hypothermic neuroprotection.

Topics: Adrenergic alpha-Agonists; Animals; Anti-Inflammatory Agents; Anticonvulsants; Antioxidants; Apoptosis; Erythropoietin; Female; Free Radical Scavengers; Humans; Hyperoxia; Hypocapnia; Hypoxia-Ischemia, Brain; Inflammation; Ischemic Preconditioning; Neuroprotective Agents; Neurotoxins; Pregnancy; Prenatal Diagnosis; Receptors, N-Methyl-D-Aspartate; Seizures

In forensic pathology, while classical morphology remains a core procedure to investigate deaths, a spectrum of ancillary procedures has been developed and incorporated to detail the pathology. Among them, postmortem biochemistry is important to investigate the systemic pathophysiological changes involved in the dying process that cannot be detected by morphology. In addition, recent advances in molecular biology have provided a procedure to investigate genetic bases of diseases that might present with sudden death, which is called 'molecular autopsy'. Meanwhile, the practical application of RNA analyses to postmortem investigation has not been accepted due to rapid decay after death; however, recent experimental and practical studies using real-time reverse transcription-PCR have suggested that the relative quantification of mRNA transcripts can be applied in molecular pathology for postmortem investigation of deaths, which may be called 'advanced molecular autopsy'. In a broad sense, forensic molecular pathology implies applied medical sciences to investigate the genetic basis of diseases, and the pathophysiology of diseases and traumas leading to death at a biological molecular level in the context of forensic pathology. The possible applications include analyses of local pathology, including tissue injury, ischemia/hypoxia and inflammation at the site of insult or specific tissue damage from intoxication, systemic responses to violence or environmental hazards, disorders due to intoxication, and systemic pathophysiology of fatal process involving major life-support organs. A review of previous studies suggests that systematic postmortem quantitative analysis of mRNA transcripts can be established from multi-faceted aspects of molecular biology and incorporated into death investigations in forensic pathology, to support and reinforce morphological evidence.

Topics: Aging; Animals; Asphyxia; Biomarkers; Erythropoietin; Forensic Pathology; Gene Expression; Glucose Transporter Type 1; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; Immunohistochemistry; Postmortem Changes; Pulmonary Surfactant-Associated Proteins; Respiratory Insufficiency; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Shock; Specimen Handling; Vascular Endothelial Growth Factor A; Violence; Wounds and Injuries

Topics: Allopurinol; Antioxidants; Antipyrine; Edaravone; Erythropoietin; Free Radical Scavengers; Free Radicals; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Neuroprotective Agents; Oxidative Stress

Traumatic brain injuries remain an area of great challenge to both neurosurgeons and neuroanaesthesiologists. The management of these injuries starts at the scene of the accident. However, strategies for preventing secondary brain injury and its sequelae are continuing to evolve. These strategies include the use of pharmacological and nonpharmacological techniques. Preventing hypoxia and the use of hypertonic saline have been shown to have favourable results on the outcome of these injuries. The use of isoflurane has been shown to have a neuronprotective effect. Propofol is thought to be the future drug of choice because of its neuroprotective properties, although these still need to be further proven through research. In this review an understanding of the pathophysiology of traumatic brain injury will be outlined in order to understand the effects of pharmacological and nonpharmacological agents on secondary brain injury.

Topics: Adolescent; Adult; Brain Injuries; Cell Death; Central Nervous System Depressants; Craniocerebral Trauma; Cyclosporine; Dexmedetomidine; Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Intracranial Hypotension; Isoflurane; Middle Aged; Neuroprotective Agents; Nitrous Oxide; Perioperative Care; Propofol; Resuscitation; Saline Solution, Hypertonic; Xenon; Young Adult

Besides its established function in erythropoiesis, erythropoietin (EPO) is currently also appreciated for its neuroprotective effects. The detrimental sequelae of prolonged cerebral hypoxia and ischemia have been shown to attenuate by EPO treatment. After binding to the EPO receptor, EPO is capable of initiating a cascade of events which--via different pathways--may lead to neuroprotection. The circumstances that determine which specific signalling route(s) are activated by EPO are largely unknown. We aim to provide the reader with a timely overview on the use of EPO in models of stroke and hypoxia-ischemia and to discuss the molecular events that underlie its neuroprotection.

Topics: Animals; Disease Models, Animal; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Neuroprotective Agents; Signal Transduction; Time Factors

Oxidative stress plays an important role in causing organ injury in the compromised fetus and neonate. Recent experimental research and clinical studies have clarified important pathways in the production of reactive oxygen and nitrogen species. Free radicals are involved in causing cerebral damage after perinatal hypoxia-ischemia affecting membrane lipids, proteins, and DNA. Anti-oxidant strategies can be used as add-on neuroprotective therapy after perinatal oxidative stress. Selective inhibitors of neuronal and inducible nitric oxide synthase, allopurinol, melatonin, and erythropoietin are among the first compounds that are ready for clinical trials.

Topics: Allopurinol; Animals; Antioxidants; Clinical Trials as Topic; Erythropoietin; Free Radicals; Humans; Hypoxia-Ischemia, Brain; Neuroprotective Agents; Nitric Oxide Synthase; Oxidative Stress; Reactive Nitrogen Species; Reactive Oxygen Species

Topics: Algorithms; Aprotinin; Blood Loss, Surgical; Blood Transfusion, Autologous; Cardiopulmonary Bypass; Coronary Artery Bypass; Erythropoietin; Evidence-Based Medicine; Female; Hematocrit; Hemodilution; Hemostasis, Surgical; Humans; Hypoxia-Ischemia, Brain; Intraoperative Complications; Male; Multicenter Studies as Topic; Premedication

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

An ancillary study of the High-Dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) trial for neonates with hypoxic-ischemic encephalopathy (HIE) and treated with therapeutic hypothermia examined the hypothesis that neonates randomized to receive erythropoietin (Epo) would have a lower seizure risk and burden compared with neonates who received placebo.. Electroencephalograms (EEGs) from 7/17 HEAL trial centers were reviewed. Seizure presence was compared across treatment groups using a logistic regression model adjusting for treatment, HIE severity, center, and seizure burden prior to the first dose. Among neonates with seizures, differences across treatment groups in median maximal hourly seizure burden were assessed using adjusted quantile regression models.. Forty-six of 150 (31%) neonates had EEG seizures (31% in Epo vs 30% in placebo, p = 0.96). Maximal hourly seizure burden after the study drug was not significantly different between groups (median 11.4 for Epo, IQR: 5.6, 18.1 vs median 9.7, IQR: 4.9, 21.0 min/h for placebo).. In neonates with HIE treated with hypothermia who were randomized to Epo or placebo, we found no meaningful between-group difference in seizure risk or burden. These findings are consistent with overall trial results, which do not support Epo use for neonates with HIE undergoing therapeutic hypothermia.. In the HEAL trial of erythropoietin (Epo) vs placebo for neonates with encephalopathy presumed due to hypoxic-ischemic encephalopathy (HIE) who were also treated with therapeutic hypothermia, electrographic seizures were detected in 31%, which is lower than most prior studies. Epo did not reduce the proportion of neonates with acute provoked seizures (31% in Epo vs 30% in placebo) or maximal hourly seizure burden after the study drug (median 11.4, IQR 5.6, 18.1 for Epo vs median 9.7, IQR 4.9, 21.0 min/h for placebo). There was no anti- or pro-convulsant effect of Epo when combined with therapeutic hypothermia for HIE.

Topics: Asphyxia; Erythropoietin; Humans; Hypothermia; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Seizures

Inconsistent enrollment among hospitals for neonatal clinical trials may lead to study populations that are not representative of the patient population in the neonatal intensive care unit. The High-Dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) trial was a multisite randomized clinical trial investigating erythropoietin as a neuroprotective treatment for term infants (those born between 37 and 42 complete weeks) with hypoxic ischemic encephalopathy. Substantial variability was noted in enrollment rate by hospital. We developed survey questions across five conceptual domains to understand systems-level issues that might contribute to variation in enrollment rate by hospital. Our study found that hospitals varied in their responses across these five domains. We propose three potential reasons that we found a lack of identifiable hospital-level factors that correlated with enrollment rates: sample-size limitations, methodological concerns, and confounding factors. Future studies with a larger sample size should be considered to evaluate contributors to hospital-level variability. This will lead to more robust recruitment strategies, improved enrollment, and decreases in the waste of research resources.

Topics: Asphyxia; Epoetin Alfa; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant; Infant, Newborn; Intensive Care Units, Neonatal; Neuroprotection

To assess whether high dose erythropoietin (Epo) treatment of cooled infants with neonatal hypoxic ischemic encephalopathy results in a higher risk of prespecified serious adverse events (SAEs).. Five hundred infants born at ≥36 weeks of gestation with moderate or severe hypoxic ischemic encephalopathy undergoing therapeutic hypothermia were randomized to Epo or placebo on days 1, 2, 3, 4, and 7. Pretreatment and posttreatment SAEs were compared with adjusted generalized linear models, with posttreatment models adjusted for the presence of a pretreatment SAE. Clinical risk factors and potential mechanisms for SAEs were also examined.. The rate of experiencing at least one posttreatment SAE did not significantly differ between groups (adjusted relative risk [aRR], 95% CI: 1.17, 0.92-1.49); however, posttreatment thrombosis was identified more often in the Epo group (n = 6, 2.3%) than the placebo group (n = 1, 0.4%; aRR, 95% CI: 5.09, 1.32-19.64). The rate of posttreatment intracranial hemorrhage identified at the treatment sites by either ultrasound or magnetic resonance imaging was slightly elevated in the Epo group (n = 61, 24%) but not significantly different from the placebo group (n = 46, 19%; aRR, 95% CI: 1.21, 0.85, 1.72).. A small increased risk of major thrombotic events was identified in the Epo treatment group.. NCT02811263.

Topics: Cold Temperature; Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant; Infant, Newborn

The ability to predict neurodevelopmental impairment (NDI) for infants diagnosed with hypoxic ischemic encephalopathy (HIE) is important for parental guidance and clinical treatment as well as for stratification of patients for future neurotherapeutic studies.. To examine the effect of erythropoietin on plasma inflammatory mediators in infants with moderate or severe HIE and to develop a panel of circulating biomarkers that improves the projection of 2-year NDI over and above the clinical data available at the time of birth.. This study is a preplanned secondary analysis of prospectively collected data from infants enrolled in the High-Dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) Trial, which tested the efficacy of erythropoietin as an adjunctive neuroprotective therapy to therapeutic hypothermia. The study was conducted at 17 academic sites comprising 23 neonatal intensive care units in the United States between January 25, 2017, and October 9, 2019, with follow-up through October 2022. Overall, 500 infants born at 36 weeks' gestation or later with moderate or severe HIE were included.. Erythropoietin treatment 1000 U/kg/dose on days 1, 2, 3, 4 and 7.. Plasma erythropoietin was measured in 444 infants (89%) within 24 hours after birth. A subset of 180 infants who had plasma samples available at baseline (day 0/1), day 2, and day 4 after birth and either died or had 2-year Bayley Scales of Infant Development III assessments completed were included in the biomarker analysis.. The 180 infants included in this substudy had a mean (SD) gestational age of 39.1 (1.5) weeks, and 83 (46%) were female. Infants who received erythropoietin had increased concentrations of erythropoietin at day 2 and day 4 compared with baseline. Erythropoietin treatment did not alter concentrations of other measured biomarkers (eg, difference in interleukin [IL] 6 between groups on day 4: -1.3 pg/mL; 95% CI, -4.8 to 2.0 pg/mL). After adjusting for multiple comparisons, we identified 6 plasma biomarkers (C5a, interleukin [IL] 6, and neuron-specific enolase at baseline; IL-8, tau, and ubiquitin carboxy-terminal hydrolase-L1 at day 4) that significantly improved estimations of death or NDI at 2 years compared with clinical data alone. However, the improvement was only modest, increasing the AUC from 0.73 (95% CI, 0.70-0.75) to 0.79 (95% CI, 0.77-0.81; P = .01), corresponding to a 16% (95% CI, 5%-44%) increase in correct classification of participant risk of death or NDI at 2 years.. In this study, erythropoietin treatment did not reduce biomarkers of neuroinflammation or brain injury in infants with HIE. Circulating biomarkers modestly improved estimation of 2-year outcomes.. ClinicalTrials.gov Identifier: NCT02811263.

Topics: Biomarkers; Brain Injuries; Erythropoietin; Female; Gestational Age; Humans; Hypoxia-Ischemia, Brain; Infant; Infant, Newborn; Male

Neonatal hypoxic-ischemic encephalopathy is an important cause of death as well as long-term disability in survivors. Erythropoietin has been hypothesized to have neuroprotective effects in infants with hypoxic-ischemic encephalopathy, but its effects on neurodevelopmental outcomes when given in conjunction with therapeutic hypothermia are unknown.. In a multicenter, double-blind, randomized, placebo-controlled trial, we assigned 501 infants born at 36 weeks or more of gestation with moderate or severe hypoxic-ischemic encephalopathy to receive erythropoietin or placebo, in conjunction with standard therapeutic hypothermia. Erythropoietin (1000 U per kilogram of body weight) or saline placebo was administered intravenously within 26 hours after birth, as well as at 2, 3, 4, and 7 days of age. The primary outcome was death or neurodevelopmental impairment at 22 to 36 months of age. Neurodevelopmental impairment was defined as cerebral palsy, a Gross Motor Function Classification System level of at least 1 (on a scale of 0 [normal] to 5 [most impaired]), or a cognitive score of less than 90 (which corresponds to 0.67 SD below the mean, with higher scores indicating better performance) on the Bayley Scales of Infant and Toddler Development, third edition.. Of 500 infants in the modified intention-to-treat analysis, 257 received erythropoietin and 243 received placebo. The incidence of death or neurodevelopmental impairment was 52.5% in the erythropoietin group and 49.5% in the placebo group (relative risk, 1.03; 95% confidence interval [CI], 0.86 to 1.24; P = 0.74). The mean number of serious adverse events per child was higher in the erythropoietin group than in the placebo group (0.86 vs. 0.67; relative risk, 1.26; 95% CI, 1.01 to 1.57).. The administration of erythropoietin to newborns undergoing therapeutic hypothermia for hypoxic-ischemic encephalopathy did not result in a lower risk of death or neurodevelopmental impairment than placebo and was associated with a higher rate of serious adverse events. (Funded by the National Institute of Neurological Disorders and Stroke; ClinicalTrials.gov number, NCT02811263.).

Topics: Administration, Intravenous; Cerebral Palsy; Double-Blind Method; Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant; Infant, Newborn; Neuroprotective Agents

To examine the frequency of placental abnormalities in a multicenter cohort of newborn infants with hypoxic-ischemic encephalopathy (HIE) and to determine the association between acuity of placental abnormalities and clinical characteristics of HIE.. Infants born at ≥36 weeks of gestation (n = 500) with moderate or severe HIE were enrolled in the High-dose Erythropoietin for Asphyxia and Encephalopathy Trial. A placental pathologist blinded to clinical information reviewed clinical pathology reports to determine the presence of acute and chronic placental abnormalities using a standard classification system.. Complete placental pathologic examination was available for 321 of 500 (64%) trial participants. Placental abnormalities were identified in 273 of 321 (85%) and were more common in infants ≥40 weeks of gestation (93% vs 81%, P = .01). A combination of acute and chronic placental abnormalities (43%) was more common than either acute (20%) or chronic (21%) abnormalities alone. Acute abnormalities included meconium staining of the placenta (41%) and histologic chorioamnionitis (39%). Chronic abnormalities included maternal vascular malperfusion (25%), villitis of unknown etiology (8%), and fetal vascular malperfusion (6%). Infants with chronic placental abnormalities exhibited a greater mean base deficit at birth (-15.9 vs -14.3, P = .049) than those without such abnormalities. Patients with HIE and acute placental lesions had older mean gestational ages (39.1 vs 38.0, P < .001) and greater rates of clinically diagnosed chorioamnionitis (25% vs 2%, P < .001) than those without acute abnormalities.. Combined acute and chronic placental abnormalities were common in this cohort of infants with HIE, underscoring the complex causal pathways of HIE.. ClinicalTrials.gov: NCT02811263.

Topics: Acute Disease; Chronic Disease; Cohort Studies; Double-Blind Method; Erythropoietin; Female; Gestational Age; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Male; Placenta Diseases; Pregnancy; Risk Factors

Perinatal asphyxia, more appropriately known as hypoxic-ischemic encephalopathy (HIE), is a condition characterized by clinical and laboratory evidence of acute or sub-acute brain injury resulting from systemic hypoxemia and/or reduced cerebral blood flow. HIE is a common and devastating clinical condition in resource-poor countries with poor treatment outcome. This paper describes the protocol for an ongoing study that aims to evaluate the neuroprotective effects of Erythropoietin (EPO) as compared to routine care in the management of moderate to severe HIE among term infants.. This study is a double-blind randomized controlled trial that will be conducted in the neonatal wards of the Lagos University Teaching Hospital (LUTH), Lagos, Nigeria, over a two-year period after ethical approvals and consents. One hundred and twenty-eight term newborns (≥ 37 weeks gestation) diagnosed with moderate/ severe HIE at admission will be allocated by randomization to receive either EPO or normal saline. All the participants will be offered standard care according to the unit protocol for HIE. Baseline investigations and close monitoring of the babies are done until discharge. Participants are followed up for 2 years to monitor their outcome (death or neurological development) using standard instruments.. Previous trials had shown that EPO confers neuroprotective benefits and improve neurological and behavioral outcome in infants with HIE both singly or as an adjuvant to therapeutic hypothermia. This study hypothesized that administering EPO to newborns with moderate /severe HIE can positively influence their clinical and neurological outcomes and will provide evidence to either support or disprove the usefulness of Erythropoietin as a sole agent in the treatment of HIE, especially in resource-limited environment with the highest burden of the disease.. The study has been registered with the Pan African Clinical trials registry on the 2nd of December 2018, with registration number PACTR201812814507775.

Topics: Asphyxia Neonatorum; Brain Injuries; Cerebrovascular Circulation; Double-Blind Method; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Neuroprotection; Neuroprotective Agents; Nigeria; Outcome Assessment, Health Care; Randomized Controlled Trials as Topic

Newborns with hypoxic-ischemic encephalopathy (HIE) may exhibit abnormalities on placental histology. In this phase II clinical trial ancillary study, we hypothesized that placental abnormalities correlate with MRI brain injury and with response to treatment.. Fifty newborns with moderate/severe encephalopathy who received hypothermia were enrolled in a double-blind, placebo-controlled trial of erythropoietin for HIE. A study pathologist reviewed all available clinical pathology reports to determine the presence of chronic abnormalities and acute chorioamnionitis. Neonatal brain MRIs were scored using a validated HIE scoring system.. Placental abnormalities in 19 of the 35 (54%) patients with available pathology reports included chronic changes (N = 13), acute chorioamnionitis (N = 9), or both (N = 3). MRI subcortical brain injury was less common in infants with a placental abnormality (26 vs. 69%, P = 0.02). Erythropoietin treatment was associated with a lower global brain injury score (median 2.0 vs. 11.5, P = 0.003) and lower rate of subcortical brain injury (33 vs. 90%, P = 0.01) among patients with no chronic placental abnormality but not in patients whose placentas harbored a chronic abnormality.. Erythropoietin treatment was associated with less brain injury only in patients whose placentas exhibited no chronic histologic changes. Placentas may provide clues to treatment response in HIE.

Topics: Brain; Brain Diseases; Double-Blind Method; Erythropoietin; Female; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Magnetic Resonance Imaging; Male; Placenta; Pregnancy

To study the effects of intermittent whole-body hypoxic preconditioning on patients with carotid artery stenosis.. Fifty patients with carotid artery stenosis were selected and randomly divided into a hypoxic intervention group (HIG) and a control group (CG). Both groups were treated with a hypoxic respiration device for 7 days (HIG: 18% oxygen, CG: 21% oxygen). Venous blood samples were taken preoperatively and postoperatively. The subjects' vital signs were recorded during and after the intervention. After the completion of the trial, the concentrations of hemoglobin, hypoxia inducible factor-1α, erythropoietin, vascular endothelial growth factor, neuron-specific enolase, S100β protein, brain-derived neurotrophic factor, serum aspartate transaminase, serum alanine aminotransferase, serum creatinine, and blood urea nitrogen were measured in the previously selected blood samples.. During the intervention, the vital signs of the HIG were significantly different from those of the CG (P < 0.05). In the HIG, postoperative concentrations of hemoglobin, erythropoietin, hypoxia inducible factor-1α, and vascular endothelial growth factor were significantly more than the preoperative values (P < 0.05). In the CG, postoperative concentrations of neuron-specific enolase and S100β protein were more than the preoperative values (P < 0.05). The concentrations of brain-derived neurotrophic factor, serum aspartate transaminase, serum alanine aminotransferase, serum creatinine, and blood urea nitrogen showed no significant differences between their preoperative and postoperative values in either the HIG or the CG (P > 0.05).. Intermittent hypoxic preconditioning can change the vital signs and hematologic indexes of patients with carotid artery stenosis without causing new postoperative complications or organ damage.

Topics: Alanine Transaminase; Aspartate Aminotransferases; Biomarkers; Blood Urea Nitrogen; Brain-Derived Neurotrophic Factor; Carotid Stenosis; Creatinine; Equipment Design; Erythropoietin; Female; Hemoglobins; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; Intraoperative Complications; Ischemic Preconditioning; Male; Middle Aged; Oxygen; Phosphopyruvate Hydratase; Postoperative Complications; Preoperative Care; Vascular Endothelial Growth Factor A

To evaluate plasma brain specific proteins and cytokines as biomarkers of brain injury in newborns with hypoxic-ischemic encephalopathy (HIE) and, secondarily, to assess the effect of erythropoietin (Epo) treatment on the relationship between biomarkers and outcomes.. A study of candidate brain injury biomarkers was conducted in the context of a phase II multicenter randomized trial evaluating Epo for neuroprotection in HIE. Plasma was collected at baseline (<24 hours) and on day 5. Brain injury was assessed by magnetic resonance imaging (MRI) and neurodevelopmental assessments at 1 year. The relationships between Epo, brain-specific proteins (S100B, ubiquitin carboxy-terminal hydrolase-L1 [UCH-L1], total Tau, neuron specific enolase), cytokines (interleukin [IL]-1β, IL-6, IL-8, IL-10, IL-12P70, IL-13, interferon-gamma [IFN-γ], tumor necrosis factor alpha [TNF-α], brain-derived neurotrophic factor [BDNF], monocyte chemoattractant protein-1), and brain injury were assessed.. In 50 newborns with encephalopathy, elevated baseline S100B, Tau, UCH-L1, IL-1β, IL-6, IL-8, IL-10, IL-13, TNF-α, and IFN-γ levels were associated with increasing brain injury severity by MRI. Higher baseline Tau and lower day 5 BDNF were associated with worse 1 year outcomes. No statistically significant evidence of Epo treatment modification on biomarkers was detected in this small cohort.. Elevated plasma brain-specific proteins and cytokine levels in the first 24 hours of life are associated with worse brain injury by MRI in newborns with HIE. Only Tau and BDNF levels were found to be related to neurodevelopmental outcomes. The effect of Epo treatment on the relationships between biomarkers and brain injury in HIE requires further study.. ClinicalTrials.gov: 01913340.

Topics: Biomarkers; Brain Injuries; Brain-Derived Neurotrophic Factor; Cytokines; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Magnetic Resonance Imaging; tau Proteins

Hypoxic-ischemic encephalopathy (HIE) remains an important cause of neonatal death and frequently leads to significant long-term disability in survivors. Therapeutic hypothermia, while beneficial, still leaves many treated infants with lifelong disabilities. Adjunctive therapies are needed, and erythropoietin (Epo) has the potential to provide additional neuroprotection.. The aim of this study was to review the current incidence, mechanism of injury, and sequelae of HIE, and to describe a new phase III randomized, placebo-controlled trial of Epo neuroprotection in term and near-term infants with moderate to severe HIE treated with therapeutic hypothermia.. This article presents an overview of HIE, neuroprotective functions of Epo, and the design of a double-blind, placebo-controlled, multicenter trial of high-dose Epo administration, enrolling 500 neonates ≥36 weeks of gestation with moderate or severe HIE diagnosed by clinical criteria.. Epo has robust neuroprotective effects in preclinical studies, and phase I/II trials suggest that multiple high doses of Epo may provide neuroprotection against brain injury in term infants. The High Dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) Trial will evaluate whether high-dose Epo reduces the combined outcome of death or neurodevelopmental disability when given in conjunction with hypothermia to newborns with moderate/severe HIE.

Topics: Asphyxia; Clinical Trials, Phase III as Topic; Double-Blind Method; Erythropoietin; Female; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Logistic Models; Male; Multicenter Studies as Topic; Neuroprotection; Neuroprotective Agents; Randomized Controlled Trials as Topic

In the Neonatal Erythropoietin and Therapeutic Hypothermia Outcomes study, 9/20 erythropoietin-treated vs 12/24 placebo-treated infants with hypoxic-ischemic encephalopathy had acute brain injury. Among infants with acute brain injury, the injury volume was lower in the erythropoietin than the placebo group (P = .004). Higher injury volume correlated with lower 12-month neurodevelopmental scores.. ClinicalTrials.gov: NCT01913340.

Topics: Brain Injuries; Double-Blind Method; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Infant; Infant, Newborn; Magnetic Resonance Imaging; Male; Neuroprotective Agents; Prospective Studies; Time Factors; Treatment Outcome; United States

High-dose erythropoietin (Epo) is a promising neuroprotective treatment in neonates with hypoxic-ischemic encephalopathy (HIE) receiving hypothermia. We evaluated the pharmacokinetics and dose-exposure relationships of high-dose Epo in this population to inform future dosing strategies.. In neonates with HIE receiving hypothermia, Epo 1,000 U/kg every 24 h for the first 2 d of therapy resulted in consistent achievement of target exposures associated with neuroprotection in animal models.

Topics: Area Under Curve; Dose-Response Relationship, Drug; Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn

Erythropoietin (EPO) is neuroprotective after asphyxia in animal studies. The efficacy and safety of EPO monotherapy in term neonates with hypoxic ischemic encephalopathy (HIE) is uncertain.. Hundred term neonates with moderate or severe HIE were randomized by random permuted block algorithm to receive either EPO 500 U kg. Death or moderate or severe disability occurred in 40% of neonates in the treatment group vs 70% in the placebo group (risk ratio, 0.57; 95% confidence interval (CI) 0.38 to 0.85; P=0.003). Death occurred in 16% of patients in both the groups (risk ratio, 1.0; 95% CI 0.33 to 2.9; P=0.61). The risk of cerebral palsy was lower among survivors in the treatment group (risk ratio, 0.52; 95% CI 0.25 to 1.03; P=0.04) and lesser number of babies were on anticonvulsants at assessment (risk ratio, 0.47; 95% CI 0.20 to 1.01; P=0.03). Neonatal brain magnetic resonance imaging showed more abnormalities in the placebo group (relative risk, 0.66; 95% CI 0.42 to 1.03; P=0.04)). Improvement in other neurological outcomes was not significant.. EPO monotherapy reduces the risk of death or disability in term neonates with moderate or severe encephalopathy.

Topics: Asphyxia Neonatorum; Brain; Cerebral Palsy; Double-Blind Method; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; India; Infant; Infant, Newborn; Longitudinal Studies; Magnetic Resonance Imaging; Male; Prospective Studies; Severity of Illness Index; Term Birth

To determine if multiple doses of erythropoietin (Epo) administered with hypothermia improve neuroradiographic and short-term outcomes of newborns with hypoxic-ischemic encephalopathy.. In a phase II double-blinded, placebo-controlled trial, we randomized newborns to receive Epo (1000 U/kg intravenously; n = 24) or placebo (n = 26) at 1, 2, 3, 5, and 7 days of age. All infants had moderate/severe encephalopathy; perinatal depression (10 minute Apgar <5, pH <7.00 or base deficit ≥15, or resuscitation at 10 minutes); and received hypothermia. Primary outcome was neurodevelopment at 12 months assessed by the Alberta Infant Motor Scale and Warner Initial Developmental Evaluation. Two independent observers rated MRI brain injury severity by using an established scoring system.. The mean age at first study drug was 16.5 hours (SD, 5.9). Neonatal deaths did not significantly differ between Epo and placebo groups (8% vs 19%, P = .42). Brain MRI at mean 5.1 days (SD, 2.3) showed a lower global brain injury score in Epo-treated infants (median, 2 vs 11, P = .01). Moderate/severe brain injury (4% vs 44%, P = .002), subcortical (30% vs 68%, P = .02), and cerebellar injury (0% vs 20%, P = .05) were less frequent in the Epo than placebo group. At mean age 12.7 months (SD, 0.9), motor performance in Epo-treated (n = 21) versus placebo-treated (n = 20) infants were as follows: Alberta Infant Motor Scale (53.2 vs 42.8, P = .03); Warner Initial Developmental Evaluation (28.6 vs 23.8, P = .05).. High doses of Epo given with hypothermia for hypoxic-ischemic encephalopathy may result in less MRI brain injury and improved 1-year motor function.

Topics: Brain; Brain Injuries; Double-Blind Method; Drug Administration Schedule; Erythropoietin; Female; Humans; Hypothermia; Hypoxia-Ischemia, Brain; Infant, Newborn; Injections, Intravenous; Magnetic Resonance Imaging; Male; Motor Skills Disorders; Neurodevelopmental Disorders; Neuropsychological Tests; Severity of Illness Index

To investigate the safety and short term outcome of high dose recombinant human erythropoietin (rhEpo) given shortly after birth and subsequently over the first 2 days for neuroprotection to very preterm infants.. Randomized, double masked phase II trial. Preterm infants (gestational age 26 0/7-31 6/7 weeks) were given rhEpo (nt = 229; 3000 U/kg body weight) or NaCl 0.9% (nc = 214) intravenously at 3, 12-18, and 36-42 hours after birth.. There were no relevant differences between the groups for short-term outcomes such as mortality, retinopathy of prematurity, intraventricular hemorrhage, sepsis, necrotizing enterocolitis, and bronchopulmonary dysplasia. At day 7-10, we found significantly higher hematocrit values, reticulocyte, and white blood cell counts, and a lower platelet count in the rhEpo group.. Early high-dose rhEpo administration to very premature infants is safe and causes no excess in mortality or major adverse events.. ClinicalTrials.gov: NCT00413946.

Topics: Bronchopulmonary Dysplasia; Developmental Disabilities; Dose-Response Relationship, Drug; Double-Blind Method; Enterocolitis, Necrotizing; Erythropoietin; Europe; Hematocrit; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Infant, Premature; Intracranial Hemorrhages; Leukocyte Count; Leukomalacia, Periventricular; Neuroprotective Agents; Platelet Count; Recombinant Proteins; Reticulocyte Count; Retinopathy of Prematurity; Sepsis

The aim of this study was to determine the population pharmacokinetics of darbepoetin alfa in hypothermic neonates with hypoxic-ischemic encephalopathy treated with hypothermia.. Neonates ≥36 weeks gestation and <12 h postpartum with moderate to severe hypoxic-ischemic encephalopathy who were undergoing hypothermia treatment were recruited in this randomized, multicenter, investigational, new drug pharmacokinetic study. Two intravenous darbepoetin alfa treatment groups were evaluated: 2 and 10 µg/kg. Serum erythropoietin concentrations were measured using an enzyme-linked immunosorbent assay. Monolix 4.3.1 was used to estimate darbepoetin alfa clearance and volume of distribution. Covariates tested included: birthweight, gestational age, postnatal age, postmenstrual age, sex, Sarnat score, and study site.. Darbepoetin alfa pharmacokinetics were well described by a one-compartment model with exponential error. Clearance and the volume of distribution were scaled by birthweight (centered on the mean) a priori. Additionally, gestational age (also centered on the mean) significantly affected darbepoetin alfa clearance. Clearance and volume of distribution were estimated as 0.0465 L/h (95% confidence interval 0.0392-0.0537) and 1.58 L (95% confidence interval 1.29-1.87), respectively.. A one-compartment model successfully described the pharmacokinetics of darbepoetin alfa among hypothermic neonates treated for hypoxic-ischemic encephalopathy. Clearance decreased with increasing gestational age.

Topics: Administration, Intravenous; Darbepoetin alfa; Double-Blind Method; Erythropoietin; Female; Hematinics; Humans; Hypothermia; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Male

To determine the safety and efficacy of single dose systemic recombinant human erythropoietin (rEPO) in neonates with perinatal hypoxic Ischemic Encephalopathy (HIE), and its effect on serum brain-derived neurotrophic factor (BDNF) and neuron-specific enolase (NSE).. Forty-five full-term neonates; 30 with perinatal HIE and 15 controls were studied. HIE neonates were randomized into three intervention groups (first 6 h of life): 10 received single subcutaneous 1500 U/kg rEPO at day-1, 10 subjected to hypothermia for 72 h and 10 received supportive care. BDNF and NSE measured during first 6 h and day 5 postnatal. Daily Thompson's score, MRI brain and neuromuscular function scale for survivors at 3 months of age were done.. Hypothermia group had best survival especially with stage-II Sarnat scale, followed by rEpo and supportive group. BDNF day-5 was significantly higher in each group compared to controls. MRI score and neuromuscular function score were non-significantly lower in the hypothermia group compared to rEPO.. Therapeutic hypothermia was superior to single dose rEpo for neuro-protection in HIE especially in patients with stage-II Sarnat scale. Therapeutic effect of combined rEPO multiple dosing and modest hypothermia therapy should be studied.

Topics: Case-Control Studies; Developing Countries; Erythropoietin; Female; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Male; Prospective Studies; Severity of Illness Index; Treatment Outcome

To study the effects of erythropoietin (EPO) on serum levels of neuron-specific enolase (NSE) and S-100B in neonates with hypoxic-ischemic encephalopathy (HIE) and the underlying mechanism.. Forty neonates with HIE were randomly divided into conventional treatment (n=20) and EPO treatment groups (n=20). Twenty healthy full-term neonates born during the same period were randomly selected as the normal control group. The conventional treatment group received conventional treatment, while the EPO treatment group received conventional treatment as well as EPO [200 IU/(kg.d)] which was given by intravenous infusion from the second day after birth. The course of treatment was 7 days. Blood samples of the three groups were collected on the first day after birth (before treatment) and the ninth day after birth (after treatment). Serum levels of NSE and S-100B were measured by double-antibody sandwich ABC-ELISA.. Before treatment, the two treatment groups had significantly higher serum NSE and S-100B levels than the normal control group (P<0.01), whereas no significant differences in the levels of NSE and S-100B were observed between the conventional treatment and EPO treatment groups (P>0.05). The serum NSE and S-100B levels on the ninth day after birth were significantly lower than those on the first day after birth in the three groups (P<0.01). After treatment, the serum NSE and S-100B levels were significantly lower in the EPO treatment group than in the conventional treatment group (P<0.05).. Dynamic monitoring of serum NSE and S-100B levels may be helpful for the early diagnosis of HIE and the assessment of brain injury repair in newborns with HIE. EPO may be helpful for the repair of neurons and glial cells.

Topics: Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Male; Phosphopyruvate Hydratase; S100 Calcium Binding Protein beta Subunit

Erythropoietin is neuroprotective in animal models of neonatal hypoxic-ischemic encephalopathy. We previously reported a phase I safety and pharmacokinetic study of erythropoietin in neonates. This article presents the neurodevelopmental follow-up of infants who were enrolled in the phase I clinical trial.. We enrolled 24 newborns with hypoxic-ischemic encephalopathy in a dose-escalation study. Patients received up to six doses of erythropoietin in addition to hypothermia. All infants underwent neonatal brain magnetic resonance imaging (MRI) reviewed by a single neuroradiologist. Moderate-to-severe neurodevelopmental disability was defined as cerebral palsy with Gross Motor Function Classification System levels III-V or cognitive impairment based on Bayley Scales of Infant Development II mental developmental index or Bayley III cognitive composite score.. Outcomes were available for 22 of 24 infants, at mean age 22 months (range, 8-34 months). There were no deaths. Eight (36%) had moderate-to-severe brain injury on neonatal MRI. Moderate-to-severe disability occurred in one child (4.5%), in the setting of moderate-to-severe basal ganglia and/or thalamic injury. Seven infants with moderate-to-severe watershed injury exhibited the following outcomes: normal (three), mild language delay (two), mild hemiplegic cerebral palsy (one), and epilepsy (one). All 11 patients with a normal brain MRI had a normal outcome.. This study is the first to describe neurodevelopmental outcomes in infants who received high doses of erythropoietin and hypothermia during the neonatal period. The findings suggest that future studies are warranted to assess the efficacy of this new potential neuroprotective therapy.

Topics: Brain; Child, Preschool; Cognition Disorders; Dose-Response Relationship, Drug; Erythropoietin; Female; Follow-Up Studies; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant; Magnetic Resonance Imaging; Male; Neuropsychological Tests; Treatment Outcome

High-dose recombinant human erythropoietin (rEpo) has first been administered in clinical trials for neuroprotection in very preterm neonates at high risk of brain injury and in (near-) term neonates with hypoxic-ischemic encephalopathy. However, recent trials in adults raised concerns about the safety of high-dose rEpo for neuro- and cardioprotection.. To evaluate the putative accumulation or renal leakage of Epo as a function of developmental stage after repetitive early short-term infusion of high-dose rEpo (3 × 3,000 U/kg within 42 h after birth; NCT00413946) for neuroprotection in very preterm infants.. Epo concentrations were measured using the ELISA technique in the first two consecutive urine specimens after each rEpo infusion.. Renal Epo excretion was significantly higher in preterm infants with gestational ages <29 weeks than in more mature infants and reached up to 23% of the administered rEpo within 8 h after each infusion. The urinary Epo concentration did not increase after three repetitive infusions of high-dose rEpo. The ratio of urinary Epo to total protein concentrations was the same in infants with gestational ages <29 weeks and in those with gestational ages ≥29 weeks.. Our data suggest that the higher renal Epo excretion in more immature infants may be attributed to a higher glomerular filtration leakage due to the lower maturation of the kidneys and argue against saturation kinetics after multiple doses of 3,000 U/kg rEpo. This information should be considered in future trials on the use of rEpo for neuroprotection in neonates.

Topics: Anemia, Neonatal; Cytoprotection; Dose-Response Relationship, Drug; Double-Blind Method; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Infant, Premature; Infusion Pumps; Male; Neurons; Neuroprotective Agents; Osmolar Concentration; Placebos; Recombinant Proteins; Time Factors

To determine the safety and pharmacokinetics of erythropoietin (Epo) given in conjunction with hypothermia for hypoxic-ischemic encephalopathy (HIE). We hypothesized that high dose Epo would produce plasma concentrations that are neuroprotective in animal studies (ie, maximum concentration = 6000-10000 U/L; area under the curve = 117000-140000 U*h/L).. In this multicenter, open-label, dose-escalation, phase I study, we enrolled 24 newborns undergoing hypothermia for HIE. All patients had decreased consciousness and acidosis (pH < 7.00 or base deficit ≥ 12), 10-minute Apgar score ≤ 5, or ongoing resuscitation at 10 minutes. Patients received 1 of 4 Epo doses intravenously: 250 (N = 3), 500 (N = 6), 1000 (N = 7), or 2500 U/kg per dose (N = 8). We gave up to 6 doses every 48 hours starting at <24 hours of age and performed pharmacokinetic and safety analyses.. Patients received mean 4.8 ± 1.2 Epo doses. Although Epo followed nonlinear pharmacokinetics, excessive accumulation did not occur during multiple dosing. At 500, 1000, and 2500 U/kg Epo, half-life was 7.2, 15.0, and 18.7 hours; maximum concentration was 7046, 13780, and 33316 U/L, and total Epo exposure (area under the curve) was 50306, 131054, and 328002 U*h/L, respectively. Drug clearance at a given dose was slower than reported in uncooled preterm infants. No deaths or serious adverse effects were seen.. Epo 1000 U/kg per dose intravenously given in conjunction with hypothermia is well tolerated and produces plasma concentrations that are neuroprotective in animals. A large efficacy trial is needed to determine whether Epo add-on therapy further improves outcome in infants undergoing hypothermia for HIE.

Topics: Analysis of Variance; Combined Modality Therapy; Dose-Response Relationship, Drug; Drug Administration Schedule; Erythropoietin; Female; Half-Life; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Infusions, Intravenous; Male; Metabolic Clearance Rate; Neuroprotective Agents

To study the efficacy of erythropoietinin (EPO) in the treatment of moderate or severe hypoxic-ischemic encephalopathy (HIE) in neonates.. Seventy neonates with moderate or severe HIE were randomly assigned to two groups: EPO treatment and control (n=35 each). The EPO treatment group included 22 cases of moderate HIE and 13 cases of severe HIE. The control group included 24 cases of moderate HIE and 11 cases of severe HIE. Thirty-five healthy full-term infants served as normal group. The control group received a conventional treatment. Beside the conventional treatment, the EPO treatment group was intravenously injected with EPO of 200 IU/kg•d, 3 times weekly. Routine blood test was performed every 6 days. EPO dose was adjusted based on the results of the routine blood test. The course of EPO treatment was 2 to 4 weeks. Neonatal Behavioral Neurological Assessment (NBNA) was performed at age of 28 days. The infant development test of Child Development Centre of China (CDCC) was performed at ages of 3 months and 6 months.. The percentage of normal NBNA scores in the EPO treatment group was significantly higher than that in the control group at age of 28 days (P<0.05), but was significantly lower than that in the normal group (P<0.01). The CDCC test including physical development index (PDI) and physical development index (MDI) showed the percentage of normal results in the EPO treatment group was significantly higher than in the control group at age of 3 months (P<0.05), but was significantly lower than in the normal group (P<0.01). The CDCC test including PDI and MDI showed that the percentage of normal results in the EPO treatment group was significantly higher than in the control group at age of 6 months. The MDI test results in the EPO treatment group were not significantly different from those in the normal group at age of 6 months, but the percentage of normal results in the PDI test in the EPO treatment group was still significantly lower than that in the normal group (P<0.05).. EPO treatment has neuroprotective effects against moderate or severe HIE and improves long-term behavioral neurological developments in neonates.

Topics: Child Development; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Infant Behavior; Infant, Newborn; Male

The goal was to examine biochemical, neurophysiologic, anatomic, and clinical changes associated with erythropoietin administration to neonates with hypoxic-ischemic encephalopathy (HIE).. We conducted a prospective case-control study with 45 neonates in 3 groups, a normal healthy group (N = 15), a HIE-erythropoietin group (N = 15; infants with mild/moderate HIE who received human recombinant erythropoietin, 2500 IU/kg, subcutaneously, daily for 5 days), and a HIE-control group (N = 15; did not receive erythropoietin). Serum concentrations of nitric oxide (NO) were measured at enrollment for the normal healthy neonates and at enrollment and after 2 weeks for the 2 HIE groups. The 2 HIE groups underwent electroencephalography at enrollment and at 2 to 3 weeks. Brain MRI was performed at 3 weeks. Neurologic evaluations and Denver Developmental Screening Test II assessments were performed at 6 months.. Compared with normal healthy neonates, the 2 HIE groups had greater blood NO concentrations (P < .001). At enrollment, the 2 HIE groups did not differ in clinical severity, seizure incidence, NO concentrations, or electroencephalographic findings. At 2 weeks of age, electroencephalographic backgrounds improved significantly (P = .01) and NO concentrations decreased (P < .001) in the HIE-erythropoietin group, compared with the HIE-control group; MRI findings did not differ between groups. At 6 months of age, infants in the HIE-erythropoietin group had fewer neurologic (P = .03) and developmental (P = .03) abnormalities.. This study demonstrates the feasibility of early administration of human recombinant erythropoietin to term neonates with HIE, to protect against encephalopathy.

Topics: Asphyxia Neonatorum; Brain; Case-Control Studies; Dose-Response Relationship, Drug; Electroencephalography; Erythropoietin; Female; Follow-Up Studies; Humans; Hypoxia-Ischemia, Brain; Infant; Infant, Newborn; Injections, Subcutaneous; Magnetic Resonance Imaging; Male; Neurologic Examination; Nitric Oxide; Prospective Studies; Recombinant Proteins

The purpose of this study was to evaluate the efficacy and safety of erythropoietin in neonatal hypoxic-ischemic encephalopathy (HIE), by using a randomized, prospective study design.. A total of 167 term infants with moderate/severe HIE were assigned randomly to receive either erythropoietin (N = 83) or conventional treatment (N = 84). Recombinant human erythropoietin, at either 300 U/kg (N = 52) or 500 U/kg (N = 31), was administered every other day for 2 weeks, starting <48 hours after birth. The primary outcome was death or disability. Neurodevelopmental outcomes were assessed at 18 months of age.. Complete outcome data were available for 153 infants. Nine patients dropped out during treatment, and 5 patients were lost to follow-up monitoring. Death or moderate/severe disability occurred for 35 (43.8%) of 80 infants in the control group and 18 (24.6%) of 73 infants in the erythropoietin group (P = .017) at 18 months. The primary outcomes were not different between the 2 erythropoietin doses. Subgroup analyses indicated that erythropoietin improved long-term outcomes only for infants with moderate HIE (P = .001) and not those with severe HIE (P = .227). No negative hematopoietic side effects were observed.. Repeated, low-dose, recombinant human erythropoietin treatment reduced the risk of disability for infants with moderate HIE, without apparent side effects.

Topics: Asphyxia Neonatorum; Brain Damage, Chronic; China; Developmental Disabilities; Disability Evaluation; Dose-Response Relationship, Drug; Drug Administration Schedule; Erythropoietin; Female; Follow-Up Studies; Humans; Hypoxia-Ischemia, Brain; Infant; Infant, Newborn; Infusions, Intravenous; Injections, Subcutaneous; Intensive Care Units, Neonatal; Male; Neurologic Examination; Prospective Studies; Psychomotor Disorders; Recombinant Proteins

Topics: Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn

Minimizing multiple organ dysfunction-related mortality and morbidity is a critical issue for patients with hypoxic-ischemic encephalopathy (HIE) receiving therapeutic hypothermia (TH). Although erythropoietin (EPO) has demonstrated protective effects on various hypoxic-ischemic organs in animal studies and clinical trials in adults, its effects on neonates with HIE require further investigation.. This study retrospectively analyzed the medical records of neonates with HIE who received TH with or without EPO (TH+EPO vs TH groups) administration in a tertiary referral hospital from January 2016 to January 2021. Data regarding patient characteristics, medical treatment, and clinical (neurological, cardiac, respiratory, gastrointestinal, hepatic, and renal) function assessments were collected. To control for confounding factors and selection bias between the two groups, a 1:1 propensity matching method was applied.. A total of 45 neonates with HIE received TH during the study period, with 24 patients (53%) in the TH+EPO group. After matching, each group enrolled 13 cases. No significant difference in mortality or hospital stay between the two groups was noted. During the first 3 days, the patients in the TH+EPO group showed significantly higher blood pressure (BP) than those in the TH group ( p < 0.05 on day 1). The TH+EPO group showed trends of higher blood hemoglobin ( p > 0.05) and creatinine ( p > 0.05) levels and lower estimated glomerular filtration rate ( p > 0.05) and urine output ( p > 0.05) during the first 2 weeks than TH group.. The use of EPO in addition to TH is safe for neonates with HIE. The neonates with moderate or severe HIE who received EPO may have a lesser risk of hypotension than those who received TH alone. Further clinical studies on renal and cardiac functions and long-term neurological effects of EPO are required.

Topics: Animals; Erythropoietin; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Kidney; Retrospective Studies

There is a critical need for development of physiological biomarkers in infants with birth asphyxia to identify the physiologic response to therapies in real time. This is an ancillary single site study of the High-Dose Erythropoietin for Asphyxia and Encephalopathy (Wu et al., 2022 [1]) to measure neurovascular coupling (NVC) non-invasively during an ongoing blinded randomized trial.. Neonates who randomized in the HEAL enrolled at a single-center Level III Neonatal Intensive Care Unit were recruited between 2017 and 2019. Neurodevelopmental impairment was blinded and defined as any of the following: cognitive score <90 on Bayley Scales of Infant Toddler Development, third edition (BSID-III), Gross Motor Function Classification Score (GMFCS) ≥1.. All twenty-seven neonates enrolled in HEAL were recruited and 3 died before complete recording. The rank-based analysis of covariance models demonstrated lack of difference in NVC between the two groups (Epo versus Placebo) that was consistent with the observed lack of effect on neurodevelopmental outcomes.. We demonstrate no difference in neurovascular coupling after Epo administration. These findings are consistent with overall negative trial results. Physiological biomarkers can help elucidate mechanisms of neuroprotective therapies in real time in future trials.

Topics: Asphyxia; Asphyxia Neonatorum; Biomarkers; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant; Infant, Newborn; Neuroprotection; Neurovascular Coupling

To investigate the neuroprotection of recombinant human erythropoietin (rhEPO) against hypoxic/ischemic (HI) insult in three-day-old rats. Postnatal day 3 (PD3) rats were randomly divided into three groups: Sham group, HI group and HI+rhEPO group. Ligation of the right common carotid artery and hypoxia to induce HI brain injury. After HI insult, the rats received intraperitoneal injection of rhEPO (5000 IU/Kg, qod) in HI+rhEPO group or equal saline in other groups. On PD10, damage of brain tissue was examined by hematoxylin-eosin (HE) staining, observation of neuronal apoptosis in the hippocampus and cortex using immunofluorescence assay (marker: TUNEL). Immunohistochemical staining or western blotting was performed to detect the expression of cyclooxygenase-2 (COX-2), Caspase-3 and phosphorylated Akt (p-Akt) protein. On PD28, cognitive ability of rats was assessed by Morris water maze test. HI injury causes brain pathological morphology and cognitive function damage in PD3 rats, which can be alleviated by rhEPO intervention. Compared with the HI group, the HI+rhEPO group showed an increase in platform discovery rate and cross platform frequency, while the search platform time was shortened (P < 0.05). The proportion of TUNEL positive neurons and the expression of COX-2 and Caspase-3 proteins in brain tissue in the hippocampus and cortex was decreased, while the expression of p-Akt protein was upregulated (P < 0.05). RhEPO could protect against the pathological and cognitive impairment of immature brain induced by HI insult. This neuroprotective activity may involve in inhibiting inflammatory and apoptosis by activation of PI3K/Akt signaling pathway.

Topics: Animals; Animals, Newborn; Brain; Caspase 3; Cyclooxygenase 2; Erythropoietin; Humans; Hypoxia; Hypoxia-Ischemia, Brain; Ischemia; Neuroprotective Agents; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley

After perinatal asphyxia, hypoxic-ischemic encephalopathy (HIE) in term infants produces long-term neurologic sequelae or death. Obtaining a reliable, evidence-based prognosis is critical. Therapeutic hypothermia is a suggested treatment for newborn babies with moderate-to-severe HIE at or near term. However, this treatment is unsuccessful in a significant proportion of newborns. This sparked a worldwide hunt for neuroprotectants that may enhance the effects of mild hypothermia. We look at erythropoietin (EPO) as a possible possibility. This research aimed to see how EPO paired with moderate hypothermia affects oxidative stress and neuroprotection in newborns with HIE. Children with HIE diagnosed and treated at the hospital were first recruited as research participants and split into two groups using a random number system. The control group got mild hypothermia therapy as part of their standard treatment, whereas the EPO group received EPO therapy in addition to mild hypothermia therapy. Statistical analysis techniques such as the Mann-Whitney U test, Chi-squared test, and t-test were used to examine the effects. The data show that the efficacies of combination therapy of mild hypothermia and EPO for infant HIE seem to be promising right now.

Topics: Child; Erythropoietin; Humans; Hypothermia; Hypoxia-Ischemia, Brain; Infant; Infant, Newborn; Neuroprotection; Oxidative Stress

Topics: Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn

Perinatal hypoxic-ischemic (HI) brain injury, often in conjunction with an inflammatory insult, is the most common cause of death or disability in neonates. Therapeutic hypothermia (TH) is the standard of care for HI encephalopathy in term and near-term infants. However, TH may not always be available or efficacious, creating a need for novel or adjunctive neurotherapeutics. Using a near-term model of inflammation-sensitized HI brain injury in postnatal day (P) 17 ferrets, animals were randomized to either the control group (

Topics: Animals; Disease Models, Animal; Erythropoietin; Ferrets; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Neuroprotection; Neuroprotective Agents; Uridine

Our previous clinical studies demonstrated the synergistic therapeutic effect induced by co-administering recombinant human erythropoietin (rhEPO) in human umbilical cord blood (hUCB) therapy for children with cerebral palsy. However, the cellular mechanism beyond the beneficial effects in this combination therapy still needs to be elucidated. A hypoxic-ischemic encephalopathy (HIE) model of neonates, representing cerebral palsy, was prepared and randomly divided into five groups (hUCB+rhEPO combination, hUCB, and rhEPO treatments over HIE, HIE control, and sham). Seven days after, hUCB was administered intraperitoneally and the rhEPO injections were started. Neurobehavioral tests showed the best outcome in the combination therapy group, while the hUCB and rhEPO alone treatments also showed better outcomes compared with the control (

Topics: Animals; Animals, Newborn; Apoptosis; Brain Injuries; Disease Models, Animal; Erythropoietin; Female; Fetal Blood; Hypoxia-Ischemia, Brain; Male; Mice; Mice, Inbred ICR; Proto-Oncogene Proteins c-akt; Recombinant Proteins; Signal Transduction

Little data are available regarding erythropoietin (Epo) utilization patterns within neonatal intensive care units (NICUs). We sought to describe the trends in Epo utilization across a large cohort of U.S. NICUs.. This is a retrospective cohort study of infants discharged from 2008 to 2017 using the Pediatrix Clinical Data Warehouse.. We identified 704,159 eligible infants from 358 sites, of whom 9,749 (1.4%) had Epo exposure. For extremely low gestational age newborns (ELGANs), Epo exposure ranged from 7.6 to 13.5%. We found significant site variability in Epo utilization in ELGANs. Among the 299 NICUs caring for ELGANs during the study period, 184 (61.5%) never used Epo for this population, whereas 21 (7%) utilized Epo in 50% or more of eligible infants. Epo was initiated at a median of 25 days in ELGANs. For infants with hypoxic-ischemic encephalopathy (HIE), Epo exposure remained ≤1% through 2014 then increased fourfold to 3.4% by 2017. The median day of Epo initiation was the day of birth for infants diagnosed with HIE.. Epo is utilized in ELGANs more commonly than for other NICU populations. Utilization patterns appear to indicate the treatment of established anemia for ELGANs and more recently for neuroprotection in patients diagnosed with HIE.

Topics: Anemia, Neonatal; Drug Evaluation; Erythropoietin; Female; Gestational Age; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Infant, Small for Gestational Age; Intensive Care Units, Neonatal; Male; Neuroprotection; Retrospective Studies; United States

Hypoxia-inducible factor-1α (HIF1α) is a major regulator of cellular adaptation to hypoxia and oxidative stress, and recent advances of prolyl-4-hydroxylase (P4H) inhibitors have produced powerful tools to stabilize HIF1α for clinical applications. However, whether HIF1α provokes or resists neonatal hypoxic-ischemic (HI) brain injury has not been established in previous studies. We hypothesize that systemic and brain-targeted HIF1α stabilization may have divergent effects. To test this notion, herein we compared the effects of GSK360A, a potent P4H inhibitor, in in-vitro oxygen-glucose deprivation (OGD) and in in-vivo neonatal HI via intracerebroventricular (ICV), intraperitoneal (IP), and intranasal (IN) drug-application routes. We found that GSK360A increased the erythropoietin (EPO), heme oxygenase-1 (HO1) and glucose transporter 1 (Glut1) transcripts, all HIF1α target-genes, and promoted the survival of neurons and oligodendrocytes after OGD. Neonatal HI insult stabilized HIF1α in the ipsilateral hemisphere for up to 24 h, and either ICV or IN delivery of GSK360A after HI increased the HIF1α target-gene transcripts and decreased brain damage. In contrast, IP-injection of GSK360A failed to reduce HI brain damage, but elevated the risk of mortality at high doses, which may relate to an increase of the kidney and plasma EPO, leukocytosis, and abundant vascular endothelial growth factor (VEGF) mRNAs in the brain. These results suggest that brain-targeted HIF1α-stabilization is a potential treatment of neonatal HI brain injury, while systemic P4H-inhibition may provoke unwanted adverse effects.

Topics: Administration, Intranasal; Animals; Animals, Newborn; Cell Survival; Enzyme Inhibitors; Erythropoietin; Glucose Transporter Type 1; Glycine; Heme Oxygenase (Decyclizing); Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Inducible Factor-Proline Dioxygenases; Hypoxia-Ischemia, Brain; Injections, Intraperitoneal; Injections, Intraventricular; Neurons; Oligodendroglia; Quinolones; Rats

Topics: Animals; Animals, Newborn; Area Under Curve; Biomarkers; Chemokines; Cytokines; Disease Models, Animal; Erythropoietin; Female; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Intercellular Signaling Peptides and Proteins; Macaca nemestrina; Monocyte Chemoattractant Proteins; Pregnancy; ROC Curve; Severity of Illness Index

MRI and MR spectroscopy (MRS) provide early biomarkers of brain injury and treatment response in neonates with hypoxic-ischaemic encephalopathy). Still, there are challenges to incorporating neuroimaging biomarkers into multisite randomised controlled trials. In this paper, we provide the rationale for incorporating MRI and MRS biomarkers into the multisite, phase III high-dose erythropoietin for asphyxia and encephalopathy (HEAL) Trial, the MRI/S protocol and describe the strategies used for harmonisation across multiple MRI platforms.. Neonates with moderate or severe encephalopathy enrolled in the multisite HEAL trial undergo MRI and MRS between 96 and 144 hours of age using standardised neuroimaging protocols. MRI and MRS data are processed centrally and used to determine a brain injury score and quantitative measures of lactate and n-acetylaspartate. Harmonisation is achieved through standardisation-thereby reducing intrasite and intersite variance, real-time quality assurance monitoring and phantom scans.. IRB approval was obtained at each participating site and written consent obtained from parents prior to participation in HEAL. Additional oversight is provided by an National Institutes of Health-appointed data safety monitoring board and medical monitor.. NCT02811263; Pre-result.

Topics: Asphyxia; Biomarkers; Clinical Trial Protocols as Topic; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Multicenter Studies as Topic; Neuroimaging

Multiple clinical trials have demonstrated the safety and efficacy of erythropoietin in improving neurodevelopmental outcomes in infants with hypoxic-ischemic encephalopathy (HIE). It is undoubtedly urgent to include only randomized controlled trials (RCTs) for more standardized systematic reviews and meta-analyses. The purpose of this study is to examine whether erythropoietin reduces the risk of death and improve neurodevelopmental disorders in infants with HIE.. The electronic databases of Cochrane Library, EMBASE, PubMed, and Web of Science were searched from the inception to June 2021 using the following key terms: "erythropoietin," "hypoxic-ischemic encephalopathy," and "prospective," for all relevant RCTs. Only English publications were included. The primary outcome was mortality rate. Secondary outcomes included neurodevelopmental disorders, brain injury, and cognitive impairment. The Cochrane risk of bias tool was independently used to evaluate the risk of bias of included RCTs by 2 reviewers.. We hypothesized that group with erythropoietin would provide better therapeutic benefits compared with control group.. 10.17605/OSF.IO/FERUS.

Topics: Clinical Protocols; Cognitive Dysfunction; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant; Meta-Analysis as Topic; Neurodevelopmental Disorders; Risk Factors; Systematic Reviews as Topic; Treatment Outcome

Recombinant human erythropoietin (rEpo) is neuroprotective in immature animals, but it is unclear whether the combination of high-dose rEpo therapy with therapeutic hypothermia can further improve outcomes. Hypothermia and rEpo independently improved neuronal survival, with greater improvement with hypothermia, and similarly reduced numbers of caspase-3 positive cells and reactive microglia after 7 days recovery. Hypothermia, but not rEpo, was associated with markedly improved EEG power, whereas both interventions improved recovery of EEG frequency. There was no significant improvement in any outcome after combined rEpo and hypothermia compared with hypothermia alone, and of concern, the combination was associated with increased numbers of cortical caspase-3-positive cells compared with ischaemia-hypothermia. These data suggest that the mechanisms of neuroprotection with hypothermia and rEpo overlap and, thus, high-dose rEpo infusion does not appear to be an effective adjunct therapy for therapeutic hypothermia.. Therapeutic hypothermia for hypoxic-ischaemic encephalopathy (HIE) provides incomplete neuroprotection. Recombinant human erythropoietin (rEpo) is neuroprotective in immature animals, but it is unclear whether adjunct rEpo therapy with therapeutic hypothermia can further improve outcomes. Near-term fetal sheep received sham-ischaemia (n = 9) or global cerebral ischaemia for 30 min (ischaemia-vehicle, n = 8), followed by intravenous infusion of rEpo (ischaemia-Epo, n = 8; 5000 U/kg loading dose, then 833.3 U/kg/h), cerebral hypothermia (ischaemia-hypothermia, n = 8), or rEpo plus hypothermia (ischaemia-Epo-hypothermia, n = 8), from 3 to 72 h post ischaemia. Fetal brains were collected 7 days after cerebral ischaemia. Cerebral ischaemia was associated with severe neuronal loss and microglial induction in the parasagittal cortex and subcortical regions. Hypothermia reduced overall neuronal loss, cortical caspase-3 and reactive microglia in the striatum and cortex, with greater recovery of electroencephalographic (EEG) power and spectral edge (SEF) from 48 h onwards. rEpo independently improved neuronal survival in the parasagittal cortex, hippocampal CA4 and thalamus, and reduced cortical caspase-3 and activated microglia in striatal and cortical areas, with greater SEF from 120 h onwards. However, ischaemia-Epo-hypothermia did not further improve outcomes compared with ischaemia-hypothermia and was associated with increased numbers of cortical caspase-3-positive cells. These findings suggest that although delayed, prolonged treatment with both hypothermia and rEpo are independently neuroprotective, they have overlapping anti-inflammatory and anti-apoptotic mechanisms, such that the delayed, high-dose rEpo infusion for 3 days did not materially augment neuroprotection with therapeutic hypothermia.

Topics: Animals; Electroencephalography; Erythropoietin; Fetus; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Sheep

Wu and colleagues analyzed the placental pathology from a subset of the neonates in the NEATO trial who had reports available and correlated the placental pathology findings with outcomes. This study highlights the importance of placental pathology, and its potential to bring precision medicine to critically-ill neonates. Placental pathology will likely aid stratification of neonates for clinical trials and accelerate progress for neurorepair.

Topics: Brain; Brain Injuries; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Magnetic Resonance Imaging; Placenta; Precision Medicine; Pregnancy

High-dose human recombinant erythropoietin (rEPO) is a promising potential neuroprotective treatment in preterm and full-term neonates with hypoxic-ischemic encephalopathy (HIE). There are limited data on the pharmacokinetics of high-dose rEPO in neonates. We examined the effects of body weight, gestation age, global asphyxia, cerebral ischemia, hypothermia and exogenous rEPO on the pharmacokinetics of high-dose rEPO in fetal sheep. Near-term fetal sheep on gestation day 129 (0.87 gestation) (full term 147 days) received sham-ischemia (

Topics: Animals; Asphyxia Neonatorum; Birth Weight; Body Weight; Combined Modality Therapy; Dose-Response Relationship, Drug; Embryonic Development; Erythropoietin; Female; Fetus; Gestational Age; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Infusions, Intravenous; Injections, Intravenous; Models, Biological; Neuroprotective Agents; Recombinant Proteins; Sheep; Species Specificity

Hypoxic-ischemic encephalopathy (HIE) has a high morbidity rate and involves severe neurologic deficits, including cerebral palsy. Therapeutic hypothermia (TH) has been shown to decrease the mortality rate and provide neuroprotection in infants with HIE. However, death and disability rates in HIE infants treated with TH remain high. Although the cellular mechanism of the neuroprotective effect of TH remains unclear, astrocytic erythropoietin (EPO) is known to be a key mediator of neuroprotection under hypoxic conditions. In the present study, we investigated the hypothermia effect on EPO expression in astrocytes and determined whether hypothermia attenuates neuronal damage via EPO signaling.. Astrocytes derived from rat cerebral cortex were cultured under oxygen/glucose deprivation (OGD). The expression of EPO and hypoxia-inducible factor (HIF), a transcription factor of EPO, was assessed. After OGD, astrocytes were cultured under normothermic (37 °C) or hypothermic (33.5 °C) conditions, and then EPO and HIF expression was assessed. After OGD, rat cortical neurons were cultured in astrocyte-conditioned medium (ACM) derived from the hypothermic group, and neuronal apoptosis was evaluated.. OGD induced EPO mRNA and protein expression, although at lower levels than hypoxia alone. HIF-1α and HIF-2α protein expression increased under hypoxia alone and OGD, although OGD increased HIF-2α protein expression less than hypoxia alone. EPO gene and protein expression after OGD was significantly higher under hypothermia. Moreover, expression of HIF-1α and HIF-2α protein was enhanced under hypothermia. In the presence of ACM derived from hypothermic astrocytes following OGD, the number of cleaved caspase 3 and TdT-mediated dUTP nick-end labeling-positive apoptotic neurons was lower than in the presence of ACM from normothermic astrocytes following OGD. Blockade of EPO signaling using anti-EPO neutralization antibody attenuated the anti-apoptotic effect of ACM derived from hypothermic astrocytes following OGD.. Hypothermia after OGD stabilized HIF-EPO signaling in astrocytes, and upregulated EPO expression could suppress neuronal apoptosis. Investigating the neuroprotective effect of EPO from astrocytes under hypothermic conditions may contribute to the development of novel neuroprotection-based therapies for HIE.

Topics: Animals; Astrocytes; Erythropoietin; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Neurons; Neuroprotection; Rats; Rats, Wistar

Hypoxic ischemic encephalopathy (HIE) is a serious condition which results in neonatal morbidity and mortality. Early prediction of HIE especially in the first six hours of birth leads to early treatment with better prognosis.. The aim of this study was to compare the concentrations of leptin, adiponectin, and erythropoietin between normal neonates and those with HIE for the possible use of these markers for assessment of the degree of HIE and as markers for early prediction of HIE.. This study was carried out on 50 appropriate for gestational age (AGA) neonates with HIE born in Tanta University Hospital during the period from June 2016 to March 2018 (Group I). This study also included 50 appropriate for gestational age (AGA) normal neonates not suffering from any complications and matched with group I in age and sex as a control group (Group II). For all neonates in both groups, the following were done: Complete prenatal, natal, and postnatal history, assessment of APGAR score at 5 and 10 minutes, complete clinical examination with special account on clinical evidence of encephalopathy including hypotonia, abnormal oculomotor or pupillary movements, weak or absent suckling, apnea, hyperpnea, or seizures, measurement of cord blood gases and measurement of serum erythropoietin, leptin and adiponectin levels by ELISA immediately after birth.. There were no significant differences between Group I and Group II regarding gestational age, male to female ratio, mode of delivery, and weight while there were significant differences regarding Apgar score at 1 and 5 minutes with significantly lower Apgar score at 1 and 5 minutes in group I compared with Group II. There were significantly lower cord blood PH and adiponectin level and significantly higher cord blood Leptin and erythropoietin in group I compared with group II. There were significant differences between cord blood adiponectin, leptin, erythropoietin, and PH in different degrees of HIE with significantly lower cord blood adiponectin and PH and significantly higher cord blood leptin and erythropoietin in severe degree of hypoxia compared with moderate degree and in moderate degree compared with mild degree of hypoxia. There was a significant positive correlation between cord blood erythropoietin and leptin and a significant negative correlation between cord blood erythropoietin and both adiponectin and PH in studied neonates with hypoxia. ROC curve showed that EPO had the best sensitivity and specificity followed by leptin then adiponectin while the PH had the least sensitivity and specificity as early predictors of hypoxic neonates.. Neonates with HIE had lower cord blood PH and adiponectin levels and higher leptin and erythropoietin levels than normal healthy neonates at birth and during the early postnatal period. The significant differences between cord blood erythropoietin, leptin, and adiponectin between neonates with hypoxia compared with normal neonates may arouse our attention about the use of these markers in the cord blood as early predictors of neonatal HIE which can lead early treatment and subsequently better prognosis.

Topics: Adiponectin; Biomarkers; Erythropoietin; Female; Fetal Blood; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Leptin; Male; Pregnancy

There is mounting experimental evidence that therapeutic hypothermia (TH) mitigates secondary mechanisms of spinal cord injury (SCI). There is a potential synergistic neuroprotective effect for SCI through the combination of TH and other promising therapies. The treatment of TH for SCI has promising results in adults, but its use is anecdotal in newborns with SCI. SCI is a rare, serious, and often fatal complication of instrumental delivery. For the first time, we describe the case of a male newborn infant with upper SCI who was born at term age and was offered whole-body cooling and erythropoietin treatment with unsuccessful outcome. There are still many unresolved issues related to TH in the SCI, some of them specific to the neonatal patient. Accurately establishing the diagnosis and its severity is crucial to redirect care for SCI and to indicate potential neuroprotective therapies. Considering the lack of therapeutic options, the extremely poor outcomes associated with acute SCI, and the extensive experience in safe use of whole-body cooling in newborn infants, we feel that moderate whole-body cooling should be offered as soon as possible after birth to the newborn infant with SCI.

Topics: Apgar Score; Cervical Vertebrae; Combined Modality Therapy; Erythropoietin; Fatal Outcome; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Male; Obstetrical Forceps; Spinal Cord Injuries; Time-to-Treatment; Treatment Outcome

Although therapeutic hypothermia improves the outcome of neonatal hypoxic-ischemic encephalopathy (HIE), its efficacy is still limited. This preliminary study evaluates the safety and feasibility of the combination therapy with erythropoietin (Epo), magnesium sulfate and hypothermia in neonates with HIE.. A combination therapy with Epo (300 U/kg every other day for 2 weeks), magnesium sulfate (250 mg/kg for 3 days) and hypothermia was started within 6 h of birth in neonates who met the institutional criteria for hypothermia therapy. All patients received continuous infusion of dopamine. Vital signs and adverse events were recorded during the therapy. Short-term and long-term developmental outcomes were also evaluated.. Nine patients were included in the study. The mean age at first intervention was 3.9 h (SD, 0.5). Death, serious adverse events or changes in vital signs likely due to intervention were not observed during hospital care. All nine patients completed the therapy. At the time of hospital discharge, eight patients had established oral feeding and did not require ventilation support. Two patients had abnormal MRI findings. At 18 months of age, eight patients received a follow-up evaluation, and three of them showed signs of severe neurodevelopmental disability.. The combination therapy with 300 U/kg Epo every other day for 2 weeks, 250 mg/kg magnesium sulphate for 3 days and therapeutic hypothermia is feasible in newborn patients with HIE.. ISRCTN33604417 retrospectively registered on 14 September 2018.

Topics: Combined Modality Therapy; Drug Administration Schedule; Erythropoietin; Feasibility Studies; Female; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Magnesium Sulfate; Male; Pilot Projects; Prospective Studies

Hypoxic-ischemic brain damage (HIBD) occurs due to intrauterine hypoxia ischemia influencing the energy supply for fetal brain cells, which affects the metabolism of the brain to make the brain suffer a severe damage. Erythropoietin (EPO), which regulates hemacytopoiesis, is a kind of cytokine. EPO is sensitive to hypoxia ischemia. In this study, we aimed to investigate the effect of EPO on the expression of Fas/FasL in brain tissues of neonatal rats with HIBD. Neonatal rats were assigned randomly to sham, HIBD, and EPO groups. Five time points for observation were 6, 12, 24, 48, and 72 h after the HIBD rat model had been established, respectively. In the HIBD group, Fas/FasL expression began to rise at 6 h, reached the peak at 12-24 h, and dropped from 24 h. In the EPO group, the expression of Fas/FasL was lower than those in HIBD group at 12, 24, and 48 h (P<0.05). Our findings suggest that EPO may reduce cell apoptosis after hypoxic-ischemic damage through reduction of the expression of Fas and FasL, and that optimal therapeutic time window is 6-24 h after HIBD.

Topics: Animals; Animals, Newborn; Brain; Erythropoietin; Fas Ligand Protein; fas Receptor; Female; Fetal Hypoxia; Hypoxia-Ischemia, Brain; Male; Random Allocation; Rats; Rats, Sprague-Dawley

Hypoxic-ischemic encephalopathy (HIE) is a common disease that occurs during the perinatal period. The primary cause of neonatal HIE is related to fetal intrauterine anoxia. Carbamylated erythropoietin (CEPO), a derivative of erythropoietin (EPO), does not exert any erythropoietic effect; however, the neuroprotective effects resemble those of EPO. Previous studies have shown the potential benefits of CEPO on the central nervous system. The present study aimed to investigate the role of CEPO in neuronal apoptosis during intrauterine HIE and the underlying mechanisms.. To validate our hypothesis, we established an intrauterine HIE model by occluding the bilateral utero-ovarian arteries of pregnant Sprague-Dawley rats. Compared to the I/R group, neuronal apoptosis in the CEPO group was significantly lower at 4, 12, 24, and 48 h (P < 0.05). CEPO significantly inhibited CC3 expression (P < 0.05) during the early-stages after ischemia-reperfusion (0.5, 4, 8, 12 and 24 h), upregulated Bcl-2 expression, and downregulated Bax expression at 4, 8, 12, and 24 h (P < 0.05).. Carbamylated erythropoietin pretreatment inhibited the expression of proapoptotic protein CC3 in brain and regulated the Bcl-2/Bax ratio, resulting in reduced neuronal apoptosis and thus resulting in a protective effect on intrauterine HIE.

Topics: Animals; Apoptosis; Disease Models, Animal; Erythropoietin; Female; Hypoxia-Ischemia, Brain; Neuroprotective Agents; Pregnancy; Rats; Rats, Sprague-Dawley; Time Factors

The memory dysfunction is one of the disastrous outcomes for perinatal hypoxia ischemia. Erythropoietin (EPO) has been demonstrated as a neuroprotective agent with multiple effects in a series of neurological diseases. We hypothesized that disruption of neural network including synapses and neurites would contribute to memory dysfunction induced by hypoxia ischemia. The aim of the present study was to elucidate the involvement of EPO on synaptogenesis and neurite repair following perinatal hypoxia ischemia. Using a neonatal hypoxia ischemia rat model, we found that EPO rescued hypoxia ischemia-induced decrease of synaptic proteins including Synapsin1 and PSD95 rather than GluR1 in the cortex and hippocampus. In addition, EPO reduced the expression of APP (an axonal injury marker), induced the expression of microtubule-associated protein MAP-2 (a dendritic marker), and restored axonal density after hypoxia ischemia. These changes contributed to improving electrophysiological properties of synapses and spatial memory performance. In summary, our data revealed an important role of EPO in synaptogenesis and neurite repair, providing a new insight into cellular mechanisms underlying cognitive and memory dysfunction associated with perinatal hypoxia ischemia.

Topics: Animals; Animals, Newborn; Cerebral Cortex; Erythropoietin; Female; Hypoxia-Ischemia, Brain; Male; Neurites; Neuroprotective Agents; Spatial Memory; Synapses

Children who are born preterm are at risk for encephalopathy of prematurity, a leading cause of cerebral palsy, cognitive delay and behavioral disorders. Current interventions are limited and none have been shown to reverse cognitive and behavioral impairments, a primary determinant of poor quality of life for these children. Moreover, the mechanisms of perinatal brain injury that result in functional deficits and imaging abnormalities in the mature brain are poorly defined, limiting the potential to target interventions to those who may benefit most. To determine whether impairments are reversible after a prenatal insult, we investigated a spectrum of functional deficits and diffusion tensor imaging (DTI) abnormalities in young adult animals. We hypothesized that prenatal transient systemic hypoxia-ischemia (TSHI) would induce multiple functional deficits concomitant with reduced microstructural white and gray matter integrity, and tested whether these abnormalities could be ameliorated using postnatal erythropoietin (EPO), an emerging neurorestorative intervention. On embryonic day 18 uterine arteries were transiently occluded for 60min via laparotomy. Shams underwent anesthesia and laparotomy for 60min. Pups were born and TSHI pups were randomized to receive EPO or vehicle via intraperitoneal injection on postnatal days 1 to 5. Gait, social interaction, olfaction and open field testing was performed from postnatal day 25-35 before brains underwent ex vivo DTI to measure fractional anisotropy, axial diffusivity and radial diffusivity. Prenatal TSHI injury causes hyperactivity, impaired gait and poor social interaction in young adult rats that mimic the spectrum of deficits observed in children born preterm. Collectively, these data show for the first time in a model of encephalopathy of prematurity that postnatal EPO treatment mitigates impairments in social interaction, in addition to gait deficits. EPO also normalizes TSHI-induced microstructural abnormalities in fractional anisotropy and radial diffusivity in multiple regions, consistent with improved structural integrity and recovery of myelination. Taken together, these results show behavioral and memory deficits from perinatal brain injury are reversible. Furthermore, resolution of DTI abnormalities may predict responsiveness to emerging interventions, and serve as a biomarker of CNS injury and recovery.

Topics: Animals; Animals, Newborn; Brain; Diffusion Tensor Imaging; Disease Models, Animal; Embryo, Mammalian; Erythropoietin; Exploratory Behavior; Female; Gait Disorders, Neurologic; Gene Expression Regulation, Developmental; Hindlimb; Hypoxia-Ischemia, Brain; Interpersonal Relations; Male; Olfaction Disorders; Pregnancy; Prenatal Injuries; Rats; Rats, Sprague-Dawley; Sex Factors; Social Behavior Disorders

Topics: Asphyxia; Asphyxia Neonatorum; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn

Topics: Angiopoietin-1; Angiopoietin-2; Animals; Apoptosis; Brain; Erythropoietin; Hypoxia-Inducible Factor 1; Hypoxia-Ischemia, Brain; Isoquinolines; Mice, Inbred C57BL; Neovascularization, Pathologic; Prolyl-Hydroxylase Inhibitors; Receptor, TIE-2; Regeneration; Signal Transduction

Recombinant human-erythropoietin (rh-EPO) has therapeutic efficacy for premature infants with brain damage during the active rehabilitation and anti-inflammation. In the present study, we found that the rh-EPO was related to the promotion of neovascularization. Our aim was to investigate whether rh-EPO augments neovascularization in the neonatal rat model of premature brain damage through the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) signaling pathway.. Postnatal day 5 (PD5), rats underwent permanent ligation of the right common carotid artery and were exposed to hypoxia for 2 h. All the rat pups were randomized into five groups as follows: (1) control group; (2) hypoxia-ischemic (HI) group; (3) HI + LY294002 group; (4) HI + rh-EPO group; and (5) HI + rh-EPO + LY294002 group. The phospho-Akt protein was tested 90 min after the whole operation, and CD34, vascular endothelial growth factor receptor 2 (VEGFR2), and vascular endothelial growth factor (VEGF) were also tested 2 days after the whole operation.. In the hypoxic and ischemic zone of the premature rat brain, the rh-EPO induced CD34+ cells to immigrate to the HI brain zone (P < 0.05) and also upregulated the VEGFR2 protein expression (P < 0.05) and VEGF mRNA level (P < 0.05) through the PI3K/Akt (P < 0.05) signaling pathway when compared with other groups.. The rh-EPO treatment augments neovascularization responses in the neonatal rat model of premature brain damage through the PI3K/Akt signaling pathway. Besides, the endogenous EPO may exist in the HI zone of rat brain and also has neovascularization function through the PI3K/Akt signaling pathway.

Topics: Animals; Animals, Newborn; Antigens, CD34; Brain; Disease Models, Animal; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Neovascularization, Physiologic; Phosphatidylinositol 3-Kinase; Pregnancy; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Signal Transduction; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factor Receptor-2

The neonatal brain is highly susceptible to oxidative stress as developing endogenous antioxidant mechanisms are overwhelmed. In the neonate, superoxide dismutase (SOD) overexpression worsens hypoxic-ischemic injury due to H2O2 accumulation in the brain. Erythropoietin (EPO) is upregulated in 2 phases after HI, early (4 h) and late (7 days), and exogenous EPO has been effective in reducing the injury, possibly through reducing oxidative stress. We hypothesized that exogenous EPO would limit injury from excess H2O2 seen in SOD1-overexpressing mice, and thus enhance recovery after HI. We first wanted to confirm our previous findings in postnatal day 7 (P7) SOD-tg (CD1) mice using a P9 model of the Vannucci procedure of HI with SOD-tg mice from a different background strain (C57Bl/6), and then determine the efficacy of EPO treatment in this strain and their wild-type (WT) littermates. Thus, mice overexpressing copper/zinc SOD1 were subjected to HI, modified for the P9 mouse, and recombinant EPO (5 U/g) or vehicle (saline) was administered intraperitoneally 3 times: at 0 h, 24 h, and 5 days. Injury was assessed 7 days after HI. In addition, protein expression for EPO and EPO receptor was assessed in the cortex and hippocampus 24 h after HI. With the moderate insult, the SOD-tg mice had greater injury than the WT overall, confirming our previous results, as did the hippocampus and striatum when analyzed separately, but not the cortex or thalamus. EPO treatment worsened injury in SOD-tg overall and in the WT and SOD-tg hippocampus and striatum. With the more severe insult, all groups had greater injury than with the moderate insult, but differences between SOD-tg and WT were no longer observed and EPO treatment had no effect. Increased protein expression of EPO was observed in the cortex of SOD-tg mice given recombinant human EPO compared to SOD-tg given vehicle. This study confirms our previous results showing greater injury with SOD overexpression in the neonatal brain after HI at P7 in a different strain. These results also suggest that EPO treatment cannot ameliorate the damage seen in situations where there is excess H2O2 accumulation, and it may exacerbate injury in settings of extreme oxidative stress.

Topics: Animals; Animals, Newborn; Brain; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Mice; Mice, Inbred C57BL; Mice, Transgenic; Oxidative Stress; Recombinant Proteins; Superoxide Dismutase-1

Cerebral palsy (CP) is the most common motor disability in childhood, with a worldwide prevalence of 1.5-4/1,000 live births. Hypoxic-ischemic encephalopathy (HIE) contributes to the burden of CP, but the long-term neuropathological findings of this association remain limited.. Thirty-four term Macaca nemestrina macaques were included in this long-term neuropathological study: 9 control animals delivered by cesarean section and 25 animals with perinatal asphyxia delivered by cesarean section after 15-18 min of umbilical cord occlusion (UCO). UCO animals were randomized to saline (n = 11), therapeutic hypothermia (TH; n = 6), or TH + erythropoietin (Epo; n = 8). Epo was given on days 1, 2, 3, and 7. Animals had serial developmental assessments and underwent magnetic resonance imaging with diffusion tensor imaging at 9 months of age followed by necropsy. Histology and immunohistochemical (IHC) staining of brain and brainstem sections were performed.. All UCO animals demonstrated and met the standard diagnostic criteria for human neonates with moderate-to-severe HIE. Four animals developed moderate-to-severe CP (3 UCO and 1 UCO + TH), 9 had mild CP (2 UCO, 3 UCO + TH, 3 UCO + TH + Epo, and 1 control), and 2 UCO animals died. None of the animals treated with TH + Epo died, had moderate-to-severe CP, or demonstrated signs of long-term neuropathological toxicity. Compared to animals grouped together as having no CP (no-CP; controls and mild CP only), animals with CP (moderate and severe) demonstrated decreased fractional anisotropy of multiple white-matter tracts including the corpus callosum and internal capsule, when using Tract-Based Spatial Statistics (TBSS). Animals with CP had decreased staining for cortical neurons and increased brainstem glial scarring compared to animals without CP. The cerebellar cell density of the internal granular layer and white matter was decreased in CP animals compared to that in control animals without CP.. In this nonhuman primate HIE model, animals treated with TH + Epo had less brain pathology noted on TBSS and IHC staining, which supports the long-term safety of TH + Epo in the setting of HIE. Animals that developed CP showed white-matter changes noted on TBSS, subtle histopathological changes in both the white and gray matter, and brainstem injury that correlated with CP severity. This HIE model may lend itself to further study of the relationship between brainstem injury and CP.

Topics: Animals; Animals, Newborn; Asphyxia Neonatorum; Cerebral Palsy; Disease Models, Animal; Erythropoietin; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Macaca nemestrina; Random Allocation

Erythropoietin (EPO), as a type of the tissue-protective cytokines, is a 30.4 kDa hematopoietic glycoprotein. The purpose of this study was to explore the neuroprotective effects of EPO on the neonatal hypoxic-ischemic-induced hippocampus injury and the MMP-2 expression.. Neonatal Sprague-Dawley (SD) rats were randomly divided into an untreated group (control) and two hypoxia-ischemia (HI) groups treated with saline control or EPO. Hippocampi were harvested at various times after return to normoxia (6 h, 24 h, 3 days and 7 days post-HI) for analyses of infarct areas and expression using histology, Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR).. EPO injections reduced the infarction and loss of brain tissue. HI group exhibited an enhanced MMP-2 positive staining compared to controls at 24 h, 3 and 7 days post-HI by immunohistochemistry. These results were confirmed by Western blot analysis of MMP-2 expression at 7 days post-HI. Levels of MMP-2 mRNA in the injured hippocampi increased significantly at 24 h and 7 days post-HI. In particular, the EPO treatment further significantly enhanced this increase.. EPO protected hypoxic-ischemic-induced neonatal brain damage by up-regulating the MMP-2 expression. Hence, systemic EPO may have potential utility for the treatment of HI injury in human newborns.

Topics: Animals; Animals, Newborn; Cerebral Infarction; Erythropoietin; Hippocampus; Hypoxia-Ischemia, Brain; Male; Matrix Metalloproteinase 2; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Up-Regulation

Hypoxic-ischemic (HI) injury to the developing brain remains a major cause of morbidity. To date, few therapeutic strategies could provide complete neuroprotection. Erythropoietin (EPO) has been shown to be beneficial in several models of neonatal HI. This study examines the effect of treatment with erythropoietin on postnatal day 2 (P2) rats introduced with HI injury.. Rats at P2 were randomized into four groups: sham, bilateral carotid artery occlusion (BCAO), BCAO + early EPO, and BCAO + late EPO groups. Pups in each group were injected with either saline or EPO (5000U/kg) intraperitoneally once at immediately (early) or 48h (late) after HI induction. Body weight was assessed at P2 before and day 7 after HI. Mortality Rate was assessed at 24h, 48h and 72h after HI and brain water content was assessed at 72h. Brain weight and expression of myelin basic protein (MBP) were assessed at day 7 and day 14. At day 31 to 35 following HI insult, neurological behavior function was assessed via Morris water maze (MWM) test.. HI cause significant higher mortality in male than in female (P=0.0445). Among the surviving animal, HI affect significantly the body growth, brain growth, MBP expression, and neurological behavior. EPO treatments at both early and late time points significantly benefit the rats in injury recovery, in which they promoted weight gains, reduced brain edema, as well as improved spatial learning ability and memory.. We demonstrated a single dose of EPO at 5000U/kg immediately or 48h after HI injury had significant benefit for the P2 rats in injury recovery, and there was no adverse effect associated with either EPO treatment.

Topics: Age Factors; Analysis of Variance; Animals; Animals, Newborn; Body Weight; Brain Edema; Developmental Disabilities; Disease Models, Animal; Erythropoietin; Hypoxia-Ischemia, Brain; Maze Learning; Myelin Basic Protein; Neuroprotective Agents; Rats; Rats, Sprague-Dawley

Infants with neonatal encephalopathy (NE) of hypoxic-ischaemic origin are at risk of oxidative and ischaemia-reperfusion injury, which may induce abnormal inflammatory responses involving excessive cytokine production and release in serum and cerebrospinal fluid (CSF). Systemic inflammation is found in infants with NE, and we therefore were interested in cytokines associated with hypoxia, including vascular endothelial growth factor (VEGF) and erythropoietin (Epo).. To investigate the relationship between Epo, VEGF levels, brain injury and outcome in a group of term infants exposed to perinatal asphyxia (PA) compared to controls.. Serum and CSF biomarkers associated with hypoxia (VEGF, Epo) were serially measured using multiplex immunoassays over days 1-4 in term infants exposed to PA including infants with NE and controls. Results were compared to severity of encephalopathy, MR brain imaging and mortality.. Ninety-four infants had 247 serum samples collected (n = 12 controls, 82 exposed to PA with 34 CSF samples), and 4 infants died. Controls had significantly lower serum Epo levels on days 1 and 2 compared to those exposed to PA (p = 0.02). Grade II/III NE was significantly associated with elevated day 2 Epo and decreased day 1 VEGF (p < 0.05; day 2 Epo AUC = 0.74, cut-off 10.05 IU/ml). Elevated serum Epo was associated with severely abnormal MRI. Mortality was associated with elevated day 3 Epo and decreased day 1 VEGF. CSF levels were all after hypothermia and were not significantly associated with outcome.. Serum Epo and VEGF may be markers of severity of hypoxia-ischaemia and brain injury as they are closely related to hypoxic exposure.

Topics: Asphyxia Neonatorum; Biomarkers; Brain; Case-Control Studies; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Ireland; Magnetic Resonance Imaging; Male; Severity of Illness Index; Tertiary Care Centers; Vascular Endothelial Growth Factor A

Preterm infants suffer central nervous system (CNS) injury from hypoxia-ischemia and inflammation - termed encephalopathy of prematurity. Mature CNS injury activates caspase and calpain proteases. Erythropoietin (EPO) limits apoptosis mediated by activated caspases, but its role in modulating calpain activation has not yet been investigated extensively following injury to the developing CNS. We hypothesized that excess calpain activation degrades developmentally regulated molecules essential for CNS circuit formation, myelination and axon integrity, including neuronal potassium-chloride co-transporter (KCC2), myelin basic protein (MBP) and phosphorylated neurofilament (pNF), respectively. Further, we predicted that post-injury EPO treatment could mitigate CNS calpain-mediated degradation. Using prenatal transient systemic hypoxia-ischemia (TSHI) in rats to mimic CNS injury from extreme preterm birth, and postnatal EPO treatment with a clinically relevant dosing regimen, we found sustained postnatal excess cortical calpain activation following prenatal TSHI, as shown by the cleavage of alpha II-spectrin (αII-spectrin) into 145-kDa αII-spectrin degradation products (αII-SDPs) and p35 into p25. Postnatal expression of the endogenous calpain inhibitor calpastatin was also reduced following prenatal TSHI. Calpain substrate expression following TSHI, including cortical KCC2, MBP and NF, was modulated by postnatal EPO treatment. Calpain activation was reflected in serum levels of αII-SDPs and KCC2 fragments, and notably, EPO treatment also modulated KCC2 fragment levels. Together, these data indicate that excess calpain activity contributes to the pathogenesis of encephalopathy of prematurity. Serum biomarkers of calpain activation may detect ongoing cerebral injury and responsiveness to EPO or similar neuroprotective strategies.

Topics: Animals; Animals, Newborn; Apoptosis; Axons; Brain Injuries; Calcium-Binding Proteins; Calpain; Caspases; Enzyme Activation; Erythropoietin; Female; Hypoxia-Ischemia, Brain; Membrane Proteins; Myelin Basic Protein; Rats, Sprague-Dawley

The hematopoietic growth factor erythropoietin (EPO) has been shown to be neuroprotective against hypoxia-ischemia (HI) in Postnatal Day 7 (P7)-P10 or adult animal models. The current study was aimed to determine whether EPO also provides long-lasting neuroprotection against HI in P5 rats, which is relevant to immature human infants. Sprague-Dawley rats at P5 were subjected to right common carotid artery ligation followed by an exposure to 6% oxygen with balanced nitrogen for 1.5 h. Human recombinant EPO (rEPO, at a dose of 5 units/g) was administered intraperitoneally one hour before or immediately after insult, followed by additional injections at 24 and 48 h post-insult. The control rats were injected with normal saline following HI. Neurobehavioral tests were performed on P8 and P20, and brain injury was examined on P21. HI insult significantly impaired neurobehavioral performance including sensorimotor, locomotor activity and cognitive ability on the P8 and P20 rats. HI insult also resulted in brain inflammation (as indicated by microglia activation) and neuronal death (as indicated by Jade B positive staining) in the white matter, striatum, cortex, and hippocampal areas of the P21 rat. Both pre- and post-treatment with rEPO significantly improved neurobehavioral performance and protected against the HI-induced neuronal death, microglia activation (OX42+) as well as loss of mature oligodendrocytes (APC-CC1+) and hippocampal neurons (Nissl+). The long-lasting protective effects of rEPO in the neonatal rat HI model suggest that to exert neurotrophic activity in the brain might be an effective approach for therapeutic treatment of neonatal brain injury induced by hypoxia-ischemia.

Topics: Animals; Astrocytes; Erythropoietin; Hippocampus; Humans; Hypoxia-Ischemia, Brain; Locomotion; Motor Disorders; Neurons; Neuroprotective Agents; Rats; Rats, Sprague-Dawley

The mTOR (mammalian target of rapamycin) signaling pathway is a master regulator of cell growth and proliferation in the nervous system. However, the effects of erythropoietin (EPO) treatment on the mTOR signaling pathway have not been elucidated in neonates with hypoxic/ischemic (H/I) brain injury.. We investigated the mechanism underlying the neuroprotective effect of EPO by analyzing the mTOR signaling pathway after H/I injury in a neonatal rat model.. Seven-day-old rats were subjected to left carotid artery ligation and hypoxic exposure (8%) for 90 min (H/I). EPO at a dose of either 3,000 U/kg or a vehicle (V) was administered by intraperitoneal injection 0, 24 and 48 h after H/I. At 72 h after H/I (postnatal day 10), 2,3,5-triphenyltetrazolium chloride staining, myelin basic protein (MBP) immunofluorescence staining and Western blot analysis of the Akt/mTOR/p70S6K pathway were performed. Neuromotor behavioral tests included Rotarod challenge and cylinder rearing test 1 performed 3 and 6 weeks after H/I.. EPO treatment resulted in significant offsetting of MBP depletion ipsilateral (p = 0.001) and contralateral (p = 0.003) to ligation. Western blot analysis showed that the relative immunoreactivity of phosphorylated (p)-Akt, p-mTOR and p-p70S6K ipsilateral to ligation was significantly decreased in the H/I+V group compared with the sham-operated groups. However, EPO treatment significantly upregulated Akt/mTOR/p70S6K signals ipsilateral to ligation compared to the H/I+V group. The behavior tests showed that EPO attenuates long-term impairment in Rotarod challenge and cylinder test performance from 3-6 weeks.. This study demonstrates an underlying mechanism of the mTOR signaling pathway after EPO treatment, which is a potential target for treating H/I-induced brain injury.

Topics: Animals; Animals, Newborn; Disease Models, Animal; Erythropoietin; Hypoxia-Ischemia, Brain; Male; Neuroprotective Agents; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Ribosomal Protein S6 Kinases, 70-kDa; Signal Transduction; TOR Serine-Threonine Kinases

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

To explore the impacts of erythropoietin on vascular endothelial growth factor receptor 2 (VEGFR2) by the extracellular signal-regulated kinase (ERK) signaling pathway in a neonatal rat model of periventricular white matter damage.. All of postnatal day 4 rats were randomized into three groups: the sham group [without hypoxia-ischemia (HI)], the HI group (HI with saline administration), and the erythropoietin (EPO) group [HI with recombinant human erythropoietin (rh-EPO) administration]. Rat pups underwent permanent ligation of the right common carotid artery, followed by 6% O2 for 2 hours or sham operation and normoxic exposure. Immediately after the HI, rats received a single intraventricular injection of rh-EPO (0.6 IU/g body mass) or saline. ERK and phosphorylation-ERK were examined at 60 minutes and 90 minutes after operation, and VEGFR2 were detected at 2 and 4 days after operation by using Western blot.. At 60 minutes and 90 minutes after operation, the proteins of phosphorylation-ERK were significantly higher in HI rats than in the sham rats and significantly higher in HI+EPO rats than in the HI rats (P<0.05). Two days after operation, VEGFR2 was not significantly different between sham and HI rats. However, the proteins of VEGFR2 were increased after administration of rh-EPO (P<0.05). Four days after operation, the proteins of VEGFR2 were significantly higher in HI rats than in the sham rats and significantly higher in HI+EPO rats than in the HI rats (P<0.05).. EPO may regulate VEGFR2 expression by affecting the intracranial ERK signaling pathways.

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

Erythropoietin (EPO) is important for angiogenesis after hypoxia/ischemia. In this study, we investigated whether recombinant human erythropoietin (rhEPO) can enhance angiogenesis, and promote cognitive function through vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR2) signaling pathway in a rat model of hypoxic-ischemic encephalopathy (HIE). RhEPO, selective VEGFR2 inhibitor (SU5416) or vehicle was administrated by intraperitoneal injection. The assessment for cognitive function begins on day 60 after anoxia. Vascular density in hippocampus and white matter damage within corpus callosum were examined on day 28 after anoxia. The expression of erythropoietin receptor (EPOR), VEGF, rapidly accelerated fibrosarcoma 1 (Raf1), and extracellular-signal-regulated kinases 1 and 2 (ERK1/2) in hippocampus were evaluated on day 7 after anoxia. RhEPO-treated anoxia rats had better cognitive recovery, higher vascular density, and less white matter damage than in the vehicle anoxia rats. These protective effects associated with increased expression of EPOR, VEGF; and increased phosphorylation of Raf1 and ERK1/2. While this up-regulation, and changes in the histopathologic and functional outcomes were abolished by SU5416. Our data indicate that rhEPO can enhance angiogenesis, reduce white matter damage, and promote cognitive recovery through VEGF/VEGFR2 signaling pathway in anoxia rats.

Topics: Angiogenesis Inducing Agents; Animals; Animals, Newborn; Cognition; Disease Models, Animal; Erythropoietin; Hippocampus; Hypoxia; Hypoxia-Ischemia, Brain; Indoles; Male; Pyrroles; Random Allocation; Rats, Sprague-Dawley; Signal Transduction; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factor Receptor-2; White Matter

Preterm birth impacts brain development and leads to chronic deficits including cognitive delay, behavioral problems, and epilepsy. Premature loss of the subplate, a transient subcortical layer that guides development of the cerebral cortex and axonal refinement, has been implicated in these neurological disorders. Subplate neurons influence postnatal upregulation of the potassium chloride co-transporter KCC2 and maturation of γ-amino-butyric acid A receptor (GABAAR) subunits. We hypothesized that prenatal transient systemic hypoxia-ischemia (TSHI) in Sprague-Dawley rats that mimic brain injury from extreme prematurity in humans would cause premature subplate loss and affect cortical layer IV development. Further, we predicted that the neuroprotective agent erythropoietin (EPO) could attenuate the injury. Prenatal TSHI induced subplate neuronal loss via apoptosis. TSHI impaired cortical layer IV postnatal upregulation of KCC2 and GABAAR subunits, and postnatal EPO treatment mitigated the loss (n ≥ 8). To specifically address how subplate loss affects cortical development, we used in vitro mechanical subplate ablation in slice cultures (n ≥ 3) and found EPO treatment attenuates KCC2 loss. Together, these results show that subplate loss contributes to impaired cerebral development, and EPO treatment diminishes the damage. Limitation of premature subplate loss and the resultant impaired cortical development may minimize cerebral deficits suffered by extremely preterm infants.

Topics: Age Factors; Animals; Animals, Newborn; Brain Injuries; Cell Death; Cerebral Cortex; Disease Models, Animal; Embryo, Mammalian; Erythropoietin; Fetal Diseases; Gene Expression Regulation, Developmental; Hypoxia-Ischemia, Brain; In Vitro Techniques; K Cl- Cotransporters; Motor Activity; Nuclear Receptor Subfamily 4, Group A, Member 2; Rats; Rats, Sprague-Dawley; Receptors, GABA-A; Symporters

Biomarkers that indicate the severity of hypoxic-ischemic brain injury and response to treatment and that predict neurodevelopmental outcomes are urgently needed to improve the care of affected neonates. We hypothesize that sequentially obtained plasma metabolomes will provide indicators of brain injury and repair, allowing for the prediction of neurodevelopmental outcomes. A total of 33 Macaca nemestrina underwent 0, 15 or 18 min of in utero umbilical cord occlusion (UCO) to induce hypoxic-ischemic encephalopathy and were then delivered by hysterotomy, resuscitated and stabilized. Serial blood samples were obtained at baseline (cord blood) and at 0.1, 24, 48, and 72 h of age. Treatment groups included nonasphyxiated controls (n = 7), untreated UCO (n = 11), UCO + hypothermia (HT; n = 6), and UCO + HT + erythropoietin (n = 9). Metabolites were extracted and analyzed using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry and quantified by PARAFAC (parallel factor analysis). Using nontargeted discovery-based methods, we identified 63 metabolites as potential biomarkers. The changes in metabolite concentrations were characterized and compared between treatment groups. Further comparison determined that 8 metabolites (arachidonic acid, butanoic acid, citric acid, fumaric acid, lactate, malate, propanoic acid, and succinic acid) correlated with early and/or long-term neurodevelopmental outcomes. The combined outcomes of death or cerebral palsy correlated with citric acid, fumaric acid, lactate, and propanoic acid. This change in circulating metabolome after UCO may reflect cellular metabolism and biochemical changes in response to the severity of brain injury and have potential to predict neurodevelopmental outcomes.

Topics: Animals; Animals, Newborn; Apgar Score; Asphyxia Neonatorum; Biomarkers; Cerebral Palsy; Disease Models, Animal; Erythropoietin; Female; Hypothermia; Hypoxia-Ischemia, Brain; Macaca nemestrina; Male; Metabolome; Umbilical Cord

We have previously shown that glutathione peroxidase (GPx) overexpressing mice (hGPx-tg) have reduced brain injury after neonatal hypoxia-ischemia (HI) as a consequence of reduced hydrogen peroxide accumulation. However, this protection is reversed with hypoxia preconditioning, raising the question of the roles of the genes regulated by hypoxia-inducible factor-1α (HIF-1α) and their transcription products, such as erythropoietin (EPO), in both the initial protection and subsequent reversal of protection. hGPx-tg and their wild-type (WT) littermates underwent the Vannucci procedure of HI brain injury at postnatal day 9 - left carotid artery ligation followed by exposure to 10% oxygen for 50 min. Brain cortices and hippocampi were subsequently collected 0.5, 4 and 24 h later for the determination of protein expression by Western blot for GPx, HIF-1α, HIF-2α, EPO, EPO receptor, ERK1/2, phospho-ERK1/2, spectrin 145/150 (as a marker of calpain-specific necrotic cell death), and spectrin 120 (as a marker of apoptotic cell death mediated via caspase-3). As expected, the GPx overexpressing mouse cortex had approximately 3 times the GPx expression as WT naïve. Also, GPx expression remained higher in the GPx overexpressing brain than WT at all time points after HI (0.5, 4, 24 h). HIF-1α was not significantly changed in hGPx-tg as a consequence of HI but decreased in the WT cortex 4 h after HI. HIF-2α decreased in the WT hippocampus after HI. EPO was higher in the GPx overexpressing cortex and hippocampus 30 min after HI compared to WT, but the EPO receptor was unchanged by HI. ERK1/2 phosphorylation increased in the hippocampus at 4 h after HI and in the cortex at 24 h after HI in both WT and hGPx-tg. Spectrin 145/150 was increased in the WT cortex at 4 and 24 h after HI, and spectrin 120 increased 24 h after HI, perhaps reflecting greater injury in the WT brain, especially at 24 h when brain injury is more evident. The effect of GPx overexpression does not appear to upregulate the HIF pathway, yet EPO was upregulated, perhaps via ERK. This might explain, in part, why cell death takes a necrotic or apoptotic path. This may also be an explanation for why the GPx overexpressing brain cannot be preconditioned. This information may prove valuable in the development of therapies for neonatal HI brain injury.

Topics: Animals; Animals, Newborn; Basic Helix-Loop-Helix Transcription Factors; Cerebral Cortex; Disease Models, Animal; Erythropoietin; Glutathione Peroxidase; Hippocampus; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; Mice; Mice, Transgenic; Mitogen-Activated Protein Kinase 1; Signal Transduction; Up-Regulation

To observe the one-year neurologic prognostic outcome of newborns with moderate and severe hypoxic-ischemic encephalopathy (HIE) who received recombinant human erythropoietin (rhuEPO) combined with exogenous monosialotetrahexosylganglioside (GM1) treatment to provide new guidelines for clinical treatment.. Seventy-six newborns with moderate and severe HIE were selected from February 2011 to February 2014 in our hospital. This study received the informed consent of our hospital's Ethics Committee and the newborns' guardians. The newborns were divided to an observation group (n = 34 cases) and a control group (n = 42 cases). All newborns underwent hypothermia and conventional treatment for their conditions. The control group received GMl treatment and observation group received rhuEPO combined with GMl treatment. The curative differences and neural behavior from these two groups were compared.. The excellent, efficient proportion and total effective rate of the newborns from the observation group were higher than the control group. The death rate, cerebral palsy and the invalid ratio of the newborns from the observation group were lower than that of the control group. Awareness, muscle tension, primitive reflex and increased intracranial pressure recovery time of the newborns in the observation group were less than those of the control group. The Neonatal Behavior Neurological Assessment (NBNA) score of both groups after the treatment of 7, 14 and 28 days were significantly higher and increased with time (p < 0.05). The MDI, PDI and DQ score of newborns from the two groups all increased after treatment of 3, 6 and 12 months than those of before, which increased with time (p < 0.05).. The rhuEPO + GMl treatment in newborns with HIE improves short-term clinical effects and long-term neurological symptoms.

Topics: Cerebral Palsy; Drug Therapy, Combination; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Male; Neurologic Examination; Prognosis; Recombinant Proteins; Severity of Illness Index; Sphingolipid Activator Proteins; Treatment Outcome

Hypoxia inducible factor (HIF)-1α is the central transcriptional factor for the regulation of oxygen-associated genes in response to hypoxia. Erythropoietin (EPO), a hematopoietic growth factor, increases oxygen availability during hypoxia/ischemia and is associated with neuroprotection following hypoxia-ischemia in laboratory models of stroke. However, EPO has failed to translate in a clinical setting. Thus, it is critical to elucidate the key players in EPO-induced neuroprotection. Our preliminary studies have shown that EPO, as a downstream gene of HIF, inhibits HIF-1α in a dose-dependent manner in an in vitro model of hypoxia-ischemia. This study is designed to elucidate the primary mediator of EPO-induced HIF-1α inhibition and subsequent cell survival/neuroprotection. Oxygen and glucose deprivation (OGD) of nerve growth factor-differentiated rat pheochromocytoma (PC-12) cells were used to model hypoxia-ischemia in an in vitro environment. The profile of HIF-1α, HIF-2α and prolyl hydroxylase domain 2 (PHD-2) expression; HIF-1α and prolyl hydroxylase (PHD-2) mRNA levels; matrix metalloproteinase (MMP)-9; and cell death was evaluated in the presence and absence of either EPO or PHD-2 inhibitor during OGD. Our findings showed that EPO treatment resulted in an increase in PHD-2 transcription and translation, inhibition of HIF-1α expression, reactive oxygen species formation, and MMP-9 activity, resulting in increased cell survival after OGD. We also observed that EPO-induced cell survival/neuroprotection was reversed by siRNA silencing of PHD-2. This led to the conclusion that PHD-2 is a key mediator of EPO-induced HIF-1α inhibition and subsequent neuroprotection in an in vitro model of hypoxia-ischemia.

Topics: Animals; Disease Models, Animal; Erythropoietin; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Inducible Factor-Proline Dioxygenases; Hypoxia-Ischemia, Brain; Neuroprotective Agents; PC12 Cells; Procollagen-Proline Dioxygenase; Rats; Reactive Oxygen Species; Transcription, Genetic; Up-Regulation

Erythropoietin (EPO) and granulocyte colony-stimulating factor (G-CSF) are likely to play broad roles in the brain. We investigated the effects of combination therapy with EPO and G-CSF in hypoxic-ischemic brain injury during the acute, subacute, and chronic phases. A total of 79 C57BL/6 mice with hypoxic-ischemic brain injury were randomly assigned acute (days 1-5), subacute (days 11-15) and chronic (days 28-32) groups. All of them were treated with G-CSF (250 μg/kg) and EPO (5000 U/kg) or saline daily for 5 consecutive days. Behavioral assessments and immunohistochemistry for angiogenesis, neurogenesis, and astrogliosis were performed with an 8-week follow-up. Hypoxia-inducible factor-1 (HIF-1) was also measured by Western blot analysis. The results showed that the combination therapy with EPO and G-CSF in the acute phase significantly improved rotarod performance and forelimb-use symmetry compared to the other groups, while subacute EPO and G-CSF therapy exhibited a modest improvement compared with the chronic saline controls. The acute treatment significantly increased the density of CD31(+) (PECAM-1) and α-smooth muscle actin(+) vessels in the frontal cortex and striatum, increased BrdU(+)/PSA-NCAM(+) neurogenesis in the subventricular zone, and decreased astroglial density in the striatum. Furthermore, acute treatment significantly increased the HIF-1 expression in the cytosol and nucleus, whereas chronic treatment did not change the HIF-1 expression, consistent with the behavioral outcomes. These results indicate that the induction of HIF-1 expression by combination therapy with EPO and G-CSF synergistically enhances not only behavioral function but also neurogenesis and angiogenesis while decreasing the astroglial response in a time-dependent manner.

Topics: Animals; Brain; Disease Models, Animal; Drug Therapy, Combination; Erythropoietin; Granulocyte Colony-Stimulating Factor; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; Male; Mice; Mice, Inbred C57BL; Motor Activity; Neurogenesis; Neuroprotective Agents

Erythropoietin (EPO) has been recognized as a neuroprotective agent. In animal models of neonatal brain injury, exogenous EPO has been shown to reduce lesion size, improve structure and function. Experimental studies have focused on short course treatment after injury. Timing, dose and length of treatment in preterm brain damage remain to be defined. We have evaluated the effects of high dose and long-term EPO treatment in hypoxic-ischemic (HI) injury in 3 days old (P3) rat pups using histopathology, magnetic resonance imaging (MRI) and spectroscopy (MRS) as well as functional assessment with somatosensory-evoked potentials (SEP). After HI, rat pups were assessed by MRI for initial damage and were randomized to receive EPO or vehicle. At the end of treatment period (P25) the size of resulting cortical damage and white matter (WM) microstructure integrity were assessed by MRI and cortical metabolism by MRS. Whisker elicited SEP were recorded to evaluate somatosensory function. Brains were collected for neuropathological assessment. The EPO treated animals did not show significant decrease of the HI induced cortical loss at P25. WM microstructure measured by diffusion tensor imaging was improved and SEP response in the injured cortex was recovered in the EPO treated animals compared to vehicle treated animals. In addition, the metabolic profile was less altered in the EPO group. Long-term treatment with high dose EPO after HI injury in the very immature rat brain induced recovery of WM microstructure and connectivity as well as somatosensory cortical function despite no effects on volume of cortical damage. This indicates that long-term high-dose EPO induces recovery of structural and functional connectivity despite persisting gross anatomical cortical alteration resulting from HI.

Topics: Animals; Animals, Newborn; Astrocytes; Cerebral Cortex; Cicatrix; Diffusion Tensor Imaging; Disease Models, Animal; Erythropoietin; Evoked Potentials, Somatosensory; Female; Hypoxia-Ischemia, Brain; Intermediate Filaments; Male; Metabolome; Metabolomics; Myelin Sheath; Neurons; Neuroprotective Agents; Organ Size; Proton Magnetic Resonance Spectroscopy; Rats; Time Factors

Recombinant human erythropoietin (rh-EPO) has been used as a drug to treat premature infant anemia for over a decade. In addition to its erythropoietic effect, rh-EPO has also been reported to have protective effects against brain injury.. Our aim was to evaluate the levels of angiogenesis-related cells (CD34+ cells) and angiogenic factors (vascular endothelial growth factor, VEGF, and angiopoietin-1, Ang-1) in a neonatal rat model of cerebral unilateral hypoxia-ischemia (HI) and to identify the effects of rh-EPO on angiogenic responses.. Postnatal day 3 (PD3) rats underwent permanent ligation of the right common carotid artery followed by 6% O2 for 4 h (HI) or sham operation and normoxic exposure (sham). Immediately after HI, the rats received a single intraperitoneal injection of rh-EPO (5 U/g) or saline. Angiogenesis-related cells (CD34+ cells) and angiogenic factors (VEGF and Ang-1) were examined on PD5, 7, 10 and 14.. Compared with the sham rats, the number of CD34+ cells in HI rats increased from PD5 to 7 but decreased from PD10 to 14. VEGF and Ang-1 mRNA levels both increased from PD5 to 14. CD34+ cells, VEGF and Ang-1 were all upregulated in rh-EPO-treated rats compared with HI rats.. In the present study, we show the angiogenic effects of rh-EPO in a rat model of neonatal cerebral unilateral HI. Our results highlight the powerful therapeutic potential of rh-EPO treatment of HI premature brain for the enhancement of angiogenic responses.

Topics: Angiogenesis Inducing Agents; Angiopoietin-1; Animals; Animals, Newborn; Antigens, CD34; Brain; Cytoprotection; Disease Models, Animal; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Neovascularization, Physiologic; Neuroprotective Agents; Pregnancy; Rats, Sprague-Dawley; Recombinant Proteins; RNA, Messenger; Time Factors; Vascular Endothelial Growth Factor A

Infants born preterm commonly suffer from a combination of hypoxia-ischemia (HI) and infectious perinatal inflammatory insults that lead to cerebral palsy, cognitive delay, behavioral issues and epilepsy. Using a novel rat model of combined late gestation HI and lipopolysaccharide (LPS)-induced inflammation, we tested our hypothesis that inflammation from HI and LPS differentially affects gliosis, white matter development and motor impairment during the first postnatal month.. Pregnant rats underwent laparotomy on embryonic day 18 and transient systemic HI (TSHI) and/or intra-amniotic LPS injection. Shams received laparotomy and anesthesia only. Pups were born at term. Immunohistochemistry with stereological estimates was performed to assess regional glial loads, and western blots were performed for protein expression. Erythropoietin ligand and receptor levels were quantified using quantitative PCR. Digigait analysis detected gait deficits. Statistical analysis was performed with one-way analysis of variance and post-hoc Bonferonni correction.. Microglial and astroglial immunolabeling are elevated in TSHI + LPS fimbria at postnatal day 2 compared to sham (both P < 0.03). At postnatal day 15, myelin basic protein expression is reduced by 31% in TSHI + LPS pups compared to shams (P < 0.05). By postnatal day 28, white matter injury shifts from the acute injury pattern to a chronic injury pattern in TSHI pups only. Both myelin basic protein expression (P < 0.01) and the phosphoneurofilament/neurofilament ratio, a marker of axonal dysfunction, are reduced in postnatal day 28 TSHI pups (P < 0.001). Erythropoietin ligand to receptor ratios differ between brains exposed to TSHI and LPS. Gait analyses reveal that all groups (TSHI, LPS and TSHI + LPS) are ataxic with deficits in stride, paw placement, gait consistency and coordination (all P < 0.001).. Prenatal TSHI and TSHI + LPS lead to different patterns of injury with respect to myelination, axon integrity and gait deficits. Dual injury leads to acute alterations in glial response and cellular inflammation, while TSHI alone causes more prominent chronic white matter and axonal injury. Both injuries cause significant gait deficits. Further study will contribute to stratification of injury mechanisms in preterm infants, and guide the use of promising therapeutic interventions.

Topics: Animals; Animals, Newborn; Axons; Brain; Calcium-Binding Proteins; Disease Models, Animal; Embryo, Mammalian; Erythropoietin; Female; Gene Expression Regulation, Developmental; Glial Fibrillary Acidic Protein; Hypoxia-Ischemia, Brain; Inflammation; Leukoencephalopathies; Lipopolysaccharides; Microfilament Proteins; Myelin Basic Protein; Pregnancy; Prenatal Exposure Delayed Effects; Rats; Rats, Sprague-Dawley; Receptors, Erythropoietin

In some regions of the hippocampus, neurogenesis persists throughout life and is upregulated following hypoxia/ischemia. The mechanisms underlying the upregulation of neurogenesis, however, are not known. Here we examined the expression of two factors thought to be involved in hypoxia-related neurogenesis, hypoxia-inducible factor-1α (HIF-1α) and brain-derived erythropoietin (EPO), in the hippocampus of neonatal rats following hypoxia-ischemia. Sprague-Dawley rat pups were exposed to hypoxia-ischemia conditions or hypoxia conditions only. For the hypoxia-ischemia experiment, the left common carotid artery of Sprague-Dawley rat pups was ligated on postnatal day 7. The pups were exposed to hypoxic conditions and then returned to normoxia for re-oxygenation. Immunohistochemical staining was performed to evaluate EPO and HIF-1α expression at various time points after re-oxygenation (1 h, 6 h, 16 h, 1 d, 3 d, and 7 d). EPO expression in the hippocampus was verified using Western blot studies. For the hypoxia-only experiment, postnatal day 7 rat pups were continuously exposed to hypoxic conditions for different durations (0.5 h, 1 h, 2 h, 3 h, and 5 h). HIF-1α expression in the hippocampus was evaluated by immunohistochemical staining. In the hypoxia-ischemia group, EPO expression was significantly altered. The EPO expression increased during re-oxygenation, peaked at 16 h, and decreased thereafter. In the hypoxia-only group, the EPO protein was not detectable. When the rat pups were returned to normoxia for re-oxygenation, there was no HIF-1α expression. HIF-1α immunoreactivity was present in the hypoxia-only group and peaked in rats exposed to continuous hypoxic conditions for 3 h. In addition, endogenous EPO increased in the neonatal rats after the hypoxia-ischemia event. Furthermore, HIF-1α was induced as a result of hypoxia. We postulate that disruption of homeostasis triggers and enhances hippocampal neurogenesis. Thus, HIF-1α/EPO hypoxic signal transduction may initiate hippocampal neurogenesis following hypoxia-ischemia.

Topics: Animals; Erythropoietin; Female; Hippocampus; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; Pregnancy; Rats; Rats, Sprague-Dawley

The aim of this study is to test the hypotheses that central auditory pathology as well as inner ear pathology is contributing mechanisms to observed hypoxic-ischemic encephalopathy (HIE) induced hearing loss and that recombinant erythropoietin (rhEPO) will reduce this cellular pathology and attenuate hearing loss.. Twenty-eight 7-day Wistar albino rat pups were divided into four groups: Control group (n=8) was given only intraperitoneal saline solution. Sham group (n=5) had only a midline neck incisions without carotid ligation under general anesthesia and administration of intraperitoneal saline solution. HIE group (n=8) and rhEPO treated group (n=7) were subjected to left common carotid artery ligation followed by 2.5h hypoxia exposure to a mixture of 8% oxygen and 92% pure nitrogen. HIE group was injected with intraperitoneal saline solution, while the rhEPO treated group received rhEPO 100 U/kg within the same volume as the saline-alone solution. At the end of the seventh week of age hearing (ABRs) was evaluated in response to clicks, 6 kHz and 8 kHz tone burst stimuli. Animals were sacrificed and both temporal lobes, cochleas and brainstems of the animals were collected. Tissue samples were evaluated with light microscopy, immunohistochemical studies, including TUNEL and caspase-3 stainings, and electron microscopy.. Hearing thresholds were elevated in HIE animals. In rhEPO treated animals, ABR values were similar to controls. HIE caused apoptotic changes in brainstem structures as shown by light microscopy and immunohistochemical methods. Apoptotic changes also were found within the organ of Corti, spiral ganglion cells and neurons of temporal lobe by electron microscopic investigation. In rhEPO animals many of these apoptotic changes were observed, but reduced compared to untreated animals.. Mechanisms underlying HIE-induced hearing loss are based on apoptosis in inner ear; however central auditory pathway pathology occurs as well, likely contributing to changes in auditory processing and perception of complex signals not reflected by the ABR threshold shifts. For both clinical and basic significance 'rhRPO' is found to reduce those effects.

Topics: Animals; Apoptosis; Caspase 3; Disease Models, Animal; Erythropoietin; Evoked Potentials, Auditory, Brain Stem; Female; Hearing Loss; Humans; Hypoxia-Ischemia, Brain; Immunohistochemistry; In Situ Nick-End Labeling; Infant, Newborn; Male; Rats; Rats, Wistar; Recombinant Proteins; Spiral Ganglion

Prematurity and perinatal hypoxia-ischemia are common problems that result in significant neurodevelopmental morbidity and high mortality worldwide. The Vannucci model of unilateral brain injury was developed to model perinatal brain injury due to hypoxia-ischemia. Because the rodent brain is altricial, i.e., it develops postnatally, investigators can model either preterm or term brain injury by varying the age at which injury is induced. This model has allowed investigators to better understand developmental changes that occur in susceptibility of the brain to injury, evolution of brain injury over time, and response to potential neuroprotective treatments. The Vannucci model combines unilateral common carotid artery ligation with a hypoxic insult. This produces injury of the cerebral cortex, basal ganglia, hippocampus, and periventricular white matter ipsilateral to the ligated artery. Varying degrees of injury can be obtained by varying the depth and duration of the hypoxic insult. This chapter details one approach to the Vannucci model and also reviews the neuroprotective effects of erythropoietin (Epo), a neuroprotective treatment that has been extensively investigated using this model and others.

Topics: Animals; Brain Injuries; Disease Models, Animal; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Neuroprotective Agents

To investigate the effects of recombine human erythropoietin (rhEPO) on neural cells apoptosis and the expression of Caspase-3 protein in brain tissue of fetal rats after intrauterine hypoxic-ischemic brain injury.. Forty-four Sprague-Dawley rats on 19 days of pregnancy were divided into rhEPO treated group, ischemia-reperfusion group and sham-operated group. Intrauterine hypoxic-ischemic injury of fetal rats was induced by bilateral occlusion of the utero-ovarian artery for 20 min. rhEPO (5000 U/kg) was injected into rats through caudal vein in rhEPO treated group while saline was injected into rats in hypoxic-ischemic group 30 min before hypoxic-ischemic injury. The brain samples in rhEPO treated group and hypoxic-ischemic group were obtained at 30 min, 3 h, 6 h, 24 h and 48 h respectively after artery clamping. There was no hypoxic-ischemic injury in sham-operated group, so the brain samples were obtained at 24 hours after sham operation. Neuroapoptosis in brain tissue was measured by TdT mediated dUTP-biotin nick end labeling (Tunel) staining. The expression of Caspase-3 protein was observed by immunohistochemistry.. The number of apoptosis cells in fetal rat hippocampus after intrauterine hypoxic-ischemic increased progressively with reperfusion. Compared with the I/R group, the number of apoptosis cells decreased in rhEPO treated group (P < 0.01). The expression of Caspase-3 increased rapidly after 3 hours from the reperfusion in the I/R group. Compared with the I/R group, there was less expression of Caspase-3 in rhEPO treated group (P < 0.01).. rhEPO showed the effects to inhibit the apoptosis of fetal neural cells and the expression of Caspase-3 protein due to intrauterine hypoxic-ischemic brain injury.

Topics: Animals; Brain; Caspase 3; Erythropoietin; Female; Fetal Hypoxia; Humans; Hypoxia-Ischemia, Brain; Ischemic Preconditioning; Male; Pregnancy; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Reperfusion Injury

To study the effects of umbilical cord blood monocytes (UCBMC) transplantation on erythropoietin (EPO) protein and oligodendrocyte progenitor cells in hypoxia-ischemia (HI) neonatal rats.. Forty seven-day-old Sprague-Dawley rats were randomly divided into normal control (N), HI, UCBMC and HI+UCBMC groups (n=10 each). Hypoxic-ischemic brain damage (HIBD) model was prepared according to the Rice method. Twenty-four hours after hypoxia, the N and HI groups were injected with 2 μL phosphate buffered saline (PBS), and the UCBMC and HI+UCBMC groups were injected with 3×10(6) UCBMC via the lateral ventricle. EPO protein and oligodendrocyte progenitor cells in the subventricular zone of the injured brain were observed by EPO/DAPI and NG2/DAPI immunofluorescence double staining, and their correlation was analyzed.. Seven days after transplantation, there were more NG2(+)DAPI(+) and EPO(+)DAPI(+) cells in the HI+UCBMC group than in the UCBMC (P<0.05), N and HI groups (P<0.01). More NG2(+)DAPI(+) and EPO(+)DAPI(+) cells were observed in the UCBMC group compared with the N and HI groups (P<0.01). There were more NG2(+)DAPI(+) cells in the N group than in the HI group (P<0.01). The number of NG2(+)DAPI(+) cells was correlated with the number of EPO(+)DAPI(+) cells in the HI+UCBMC group (r=0.898, β=1.4604, P<0.01).. UCBMC can promote expression of oligodendrocyte progenitor cells, which is correlated with an increase in EPO protein and thus repairs brain white matter damage in neonatal rats with HIBD.

Topics: Animals; Animals, Newborn; Erythropoietin; Fetal Blood; Hypoxia-Ischemia, Brain; Monocytes; Oligodendroglia; Rats; Rats, Sprague-Dawley; Stem Cells

Brain injury from preterm birth causes white matter injury (WMI), and it leads to chronic neurological deficits including cerebral palsy, epilepsy, cognitive, and behavioral delay. Immature O4+ oligodendrocytes are particularly vulnerable to WMI. Understanding how the developing brain recovers after injury is essential to finding more effective therapeutic strategies. Erythropoietin (EPO) promotes neuronal recovery after injury; however, its role in enhancing oligodendroglial lineage recovery is unclear. Previously, we found that recombinant EPO (rEPO) treatment enhances myelin basic protein (MBP) expression and functional recovery in adult rats after prenatal transient systemic hypoxia-ischemia (TSHI). We hypothesized that after injury, rEPO would enhance oligodendroglial lineage cell genesis, survival, maturation, and myelination.. In vitro assays were used to define how rEPO contributes to specific stages of oligodendrocyte development and recovery after TSHI.. After prenatal TSHI injury, rEPO promotes genesis of oligodendrocyte progenitors from oligodendrospheres, survival of oligodendrocyte precursor cells (OPCs) and O4+ immature oligodendrocytes, O4+ cell process extension, and MBP expression. rEPO did not alter OPC proliferation.. Together, these studies demonstrate that EPO signaling promotes critical stages of oligodendroglial lineage development and recovery after prenatal TSHI injury. EPO treatment may be beneficial to preterm and other infant patient populations with developmental brain injury hallmarked by WMI.

Topics: Animals; Base Sequence; Brain Injuries; Cell Division; DNA Primers; Erythropoietin; Female; Hypoxia-Ischemia, Brain; Neurogenesis; Oligodendroglia; Pregnancy; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Signal Transduction

Up to 65% of untreated infants suffering from moderate to severe hypoxic-ischemic encephalopathy (HIE) are at risk of death or major disability. Therapeutic hypothermia (HT) reduces this risk to approximately 50% (number needed to treat: 7-9). Erythropoietin (Epo) is a neuroprotective treatment that is promising as an adjunctive therapy to decrease HIE-induced injury because Epo decreases apoptosis, inflammation, and oxidative injury and promotes glial cell survival and angiogenesis. We hypothesized that HT and concurrent Epo will be safe and effective, improve survival, and reduce moderate-severe cerebral palsy (CP) in a term nonhuman primate model of perinatal asphyxia.. Thirty-five Macaca nemestrina were delivered after 15-18 min of umbilical cord occlusion (UCO) and randomized to saline (n = 14), HT only (n = 9), or HT+Epo (n = 12). There were 12 unasphyxiated controls. Epo (3,500 U/kg × 1 dose followed by 3 doses of 2,500 U/kg, or Epo 1,000 U/kg/day × 4 doses) was given on days 1, 2, 3, and 7. Timed blood samples were collected to measure plasma Epo concentrations. Animals underwent MRI/MRS and diffusion tensor imaging (DTI) at <72 h of age and again at 9 months. A battery of weekly developmental assessments was performed.. UCO resulted in death or moderate-severe CP in 43% of saline-, 44% of HT-, and 0% of HT+Epo-treated animals. Compared to non-UCO control animals, UCO animals exhibit poor weight gain, behavioral impairment, poor cerebellar growth, and abnormal brain DTI. Compared to UCO saline, UCO HT+Epo improved motor and cognitive responses, cerebellar growth, and DTI measures and produced a death/disability relative risk reduction of 0.911 (95% CI -0.429 to 0.994), an absolute risk reduction of 0.395 (95% CI 0.072-0.635), and a number needed to treat of 2 (95% CI 2-14). The effects of HT+Epo on DTI included an improved mode of anisotropy, fractional anisotropy, relative anisotropy, and volume ratio as compared to UCO saline-treated infants. No adverse drug reactions were noted in animals receiving Epo, and there were no hematology, liver, or kidney laboratory effects.. HT+Epo treatment improved outcomes in nonhuman primates exposed to UCO. Adjunctive use of Epo combined with HT may improve the outcomes of term human infants with HIE, and clinical trials are warranted.

Topics: Animals; Asphyxia; Brain; Disease Models, Animal; Epoetin Alfa; Erythropoietin; Humans; Hypothermia; Hypoxia-Ischemia, Brain; Infant; Macaca nemestrina; Recombinant Proteins; Treatment Outcome

Hypoxic-ischemic (HI) injury to the developing brain remains a major cause of morbidity. Hypothermia is effective but does not provide complete neuroprotection, prompting a search for adjunctive therapies. Erythropoietin (Epo) has been shown to be beneficial in several models of neonatal HI. This study examines combination hypothermia and treatment with erythropoietin in neonatal rat HI.. Rats at postnatal day 7 were subjected to HI (Vannucci model) and randomized into four groups: no treatment, hypothermia alone, Epo alone, or hypothermia and Epo. Epo (1,000 U/kg) was administered in three doses: immediately following HI, and 24 h and 1 wk later. Hypothermia consisted of whole-body cooling for 8 h. At 2 and 6 wk following HI, sensorimotor function was assessed via cylinder-rearing test and brain damage by injury scoring. Sham-treated animals not subjected to HI were also studied.. Differences between experimental groups, except for Epo treatment on histopathological outcome in males, were not statistically significant, and combined therapy had no adverse effects.. No significant benefit was observed from treatment with either hypothermia or combination therapy. Future studies may require older animals, a wider range of functional assays, and postinsult assessment of injury severity to identify only moderately damaged animals for targeted therapy.

Topics: Animals; Animals, Newborn; Blood Glucose; Body Temperature; Erythropoietin; Histological Techniques; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Male; Rats

Both hypothermia and erythropoietin (EPO) are reported to have neuroprotective effects after perinatal hypoxia-ischemia (HI). We investigated a possible additive effect of the use of a combination of hypothermia-EPO in a rat model of neonatal HI.. At postnatal day 7, rats were subjected to HI and then randomized to 3 h of hypothermia, EPO, or both. Sensorimotor function was assessed by the cylinder-rearing test (CRT) at 2 and 5 wk after HI. Brain lesion volume and white matter loss were determined by hematoxylin-eosin and luxol fast blue staining, respectively.. Multivariable analysis using general linear modeling showed that hypothermia, EPO, and the interaction hypothermia × gender were determinants of sensorimotor function, both at 2 and 5 wk after HI. Neuroprotective effects of hypothermia at 5 wk were more pronounced in females, showing 52% improvement in the CRT. Maximal improvement in males was 26% after combined treatment with hypothermia and EPO. Histological outcome was improved by hypothermia only with no additional effect of EPO or gender.. Hypothermia after HI improved sensorimotor function in females more than in males. There was a borderline additive effect of EPO when combined with hypothermia. Histology of brain lesion volume and white matter damage was improved only by hypothermia.

Topics: Animals; Animals, Newborn; Blood Glucose; Body Temperature; Erythropoietin; Female; Histological Techniques; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Linear Models; Male; Neuroprotective Agents; Rats; Sex Factors

Topics: Animals; Erythropoietin; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Male

In addition to its role in erythropoiesis, erythropoietin is also appreciated for its neuroprotective effects, and it has been suggested for treatment of some ischemic-hypoxic neurovascular diseases. The protective effects of endogenous erythropoietin in the brain give rise to the hypothesis that modulating erythropoietin expression might be a better way for treatment of ischemia-hypoxia neurovascular diseases. We have found that ethanol extract of Portulaca oleracea L. (EEPO) could increase erythropoietin expression in hypoxic mouse brain in our previous study. The present study is to investigate whether EEPO exerts its neuroprotective effects against hypoxia injury through regulating endogenous erythropoietin expression. The results demonstrated that EEPO decreased the serum neuron specific enolase level in hypoxia mice and the activity of caspase-3 in neuron, increased the neuron viability and attenuated the pathological damages caused by the hypoxia condition. Importantly, we also found that EEPO stimulated the endogenous erythropoietin expression at both mRNA and protein levels. Using the conditioned medium containing soluble erythropoietin receptor, we found that the neuroprotective effects of EEPO were dependent, at least partly, on erythropoietin expression. Although EEPO did not affect transcription of hypoxia inducible factor-1α (HIF-1α), it did stabilize expression of HIF-1α. It is concluded that EEPO has neuroprotective effects against hypoxia injury, which is at least partly through stimulating endogenous erythropoietin expression by stabilizing HIF-1α.

Topics: Animals; Caspase 3; Cells, Cultured; Erythropoiesis; Erythropoietin; Ethanol; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; Mice; Mice, Inbred ICR; Neurons; Neuroprotective Agents; Plant Extracts; Portulaca; Receptors, Erythropoietin

Perinatal hypoxia-ischemia (HI) frequently causes white-matter injury, leading to severe neurological deficits and mortality, and only limited therapeutic options exist. The white matter of animal models and human patients with HI-induced brain injury contains increased numbers of oligodendrocyte progenitor cells (OPCs). However, the origin and fates of these OPCs and their potential to repair injured white matter remain unclear. Here, using cell-type- and region-specific genetic labeling methods in a mouse HI model, we characterized the Olig2-expressing OPCs. We found that after HI, Olig2+ cells increased in the posterior part of the subventricular zone (pSVZ) and migrated into the injured white matter. However, their oligodendrocytic differentiation efficiency was severely compromised compared with the OPCs in normal tissue, indicating the need for an intervention to promote their differentiation. Erythropoietin (EPO) treatment is a promising candidate, but it has detrimental effects that preclude its clinical use for brain injury. We found that long-term postinjury treatment with a nonerythropoietic derivative of EPO, asialo-erythropoietin, promoted the maturation of pSVZ-derived OPCs and the recovery of neurological function, without affecting hematopoiesis. These results demonstrate the limitation and potential of endogenous OPCs in the pSVZ as a therapeutic target for treating neonatal white-matter injury.

Topics: Animals; Animals, Newborn; Asialoglycoproteins; Basic Helix-Loop-Helix Transcription Factors; Cell Differentiation; Cell Proliferation; Cerebral Ventricles; Erythropoietin; Gene Expression; Humans; Hypoxia-Ischemia, Brain; Mice; Mice, Inbred ICR; Mice, Transgenic; Nerve Tissue Proteins; Oligodendrocyte Transcription Factor 2; Oligodendroglia; Stem Cells

Hypoxia-ischemia (HI) and associated brain injuries are seen in premature as well as term infants with birth complications. The resulting impairments involve deficits in many cognitive domains, including language development. Poor rapid auditory processing is hypothesized to be one possible underlying factor leading to subsequent language delays. Mild hypothermia treatment for HI injuries in term infants is widely used as an intervention but can be costly and time consuming. Data suggest that the effectiveness of hypothermia treatment following HI injury declines beyond 6 h following injury. Consequently, the availability of a therapeutic alternative without these limitations could allow doctors to treat HI-injured infants more effectively and thus reduce deleterious cognitive and language outcomes. Evidence from both human studies and animal models of neonatal HI suggests that erythropoietin (Epo), an endogenous cytokine hormone, may be a therapeutic agent that can ameliorate HI brain injury and preserve subsequent cognitive development and function. The current study sought to investigate the therapeutic effectiveness of Epo when administered immediately after HI injury, or delayed at intervals following the injury, in neonatal rodents. Rat pups received an induced HI injury on postnatal day 7, followed by an intraperitoneal injection of Epo (1,000 U/kg) immediately, 60 min, or 180 min following induction of injury. Subjects were tested on rapid auditory processing tasks in juvenile (P38-42) and adult periods (P80-85). Ventricular and cortical size was also measured from post mortem tissue. Results from the current study show a therapeutic benefit of Epo when given immediately following induction of HI injury, with diminished benefit from a 60-min-delayed injection of Epo and no protection following a 180-min-delayed injection. The current data thus show that the effectiveness of a single dose of Epo in ameliorating auditory processing deficits following HI injury decreases precipitously as treatment is delayed following injury. These data may have important implications for experimental human neonatal intervention with Epo.

Topics: Animals; Animals, Newborn; Disease Models, Animal; Erythropoietin; Hypoxia-Ischemia, Brain; Male; Neuroprotective Agents; Rats; Rats, Wistar

There are mixed reports on the neuroprotective properties of erythropoietin (EPO) in animal models of birth asphyxia. We investigated the effect of EPO on short- and long-term outcome after neonatal hypoxic-ischemic (HI) brain injury in mice and compared the effect of two different dose regimens of EPO. Nine-day-old mice were subjected to HI, and EPO was injected i.p. at 0, 24, and 48 h after HI in a dose of either 5 or 20 kU/kg. Paw preference in the cylinder rearing test (CRT) was used as a measure of sensorimotor function. Only in female mice, administration of EPO at 5 kU/kg but not 20 kU/kg improved sensorimotor function, reduced striatum atrophy and hippocampal lesion volume, and enhanced myelin basic protein (MBP) staining as determined at 4 and 9 wk after HI. In addition, at 72 h after HI, more Ki 67 cells were found in the subventricular zone and dentate gyrus after EPO 5 kU/kg treatment, indicating an increase in progenitor cell proliferation. In conclusion, EPO improves sensorimotor function after neonatal HI and protects against striatum atrophy, hippocampus injury, and white matter loss. The protective effect of EPO is dose-dependent and only present in females.

Topics: Animals; Apoptosis; Cell Proliferation; Dose-Response Relationship, Drug; Erythropoietin; Female; Hippocampus; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Male; Mice; Myelin Basic Protein; Myelin Sheath; Neurogenesis; Psychomotor Performance; Sex Factors; Time Factors

Topics: Apoptosis; Cell Proliferation; Dose-Response Relationship, Drug; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Male; Neurogenesis; Sex Factors

Erythropoietin (EPO) is a cytokine hormone with cytoprotective effects in many tissues including the brain. Although the benefits of administration of recombinant human EPO (rhEPO) for neonatal hypoxic brain injury have been demonstrated in neuronal tissue, the effect on non-neuronal cell populations is unclear. We tested the hypothesis that rhEPO would not only protect neuronal cells but also glial cells at a stage of brain development where their maturation was particularly sensitive, and also protect the vasculature. This was evaluated in a rat model of hypoxic injury. 1000 IU/kg rhEPO was delivered intraperitoneally at the start of 4 h hypoxia or normoxia. Treatment groups of neonatal rats (day of birth, at least N = 10 per group) were as follows: normoxia; normoxia plus rhEPO; hypoxia (8% FiO(2) delivered in temperature-controlled chambers); and hypoxia plus rhEPO. Day of birth in rats is equivalent to human gestation of 28-32 weeks. The effects of rhEPO administration, especially to non-neuronal cell populations, and the associated molecular pathways, were investigated. Apoptosis was increased with hypoxia and this was significantly reduced with rhEPO (p < 0.05). The neuronal marker, microtubule-associated protein-2, increased in expression (p < 0.05) when apoptosis was significantly reduced by rhEPO. In addition, compared with hypoxia alone, rhEPO-treated hypoxia had the following significant protein expression increases (p < 0.05): the intermediate filament structural protein nestin; myelin basic protein (oligodendrocytes); and glial fibrillary acidic protein (astrocytes). In conclusion, rhEPO protects the developing brain via anti-apoptotic mechanisms and promotes the health of non-neuronal as well as neuronal cell populations at a time when loss of these cells would have long-lasting effects on brain function.

Topics: Animals; Animals, Newborn; Apoptosis; Astrocytes; Disease Models, Animal; Drug Evaluation, Preclinical; Erythropoietin; Hypoxia-Ischemia, Brain; Intermediate Filament Proteins; Nerve Tissue Proteins; Nestin; Neurons; Oligodendroglia; Oxidative Stress; Rats; Receptors, Erythropoietin; Recombinant Proteins; Signal Transduction

Previous studies have shown that erythropoietin (EPO) is neuroprotective in both in vivo and in vitro models of hypoxia ischemia. However these studies hold limited clinical translations because the underlying mechanism remains unclear and the key molecules involved in EPO-induced neuroprotection are still to be determined. This study investigated if tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and its upstream regulator signaling molecule Janus kinase-2 (JAK-2) are critical in EPO-induced neuroprotection. Hypoxia ischemia (HI) was modeled in-vitro by oxygen and glucose deprivation (OGD) and in-vivo by a modified version of Rice-Vannucci model of HI in 10-day-old rat pups. EPO treated cells were exposed to AG490, an inhibitor of JAK-2 or TIMP-1 neutralizing antibody for 2h with OGD. Cell death, phosphorylation of JAK-2 and signal transducers and activators of transcription protein-3 (STAT-3), TIMP-1 expression, and matrix metalloproteinase-9 (MMP-9) activity were measured and compared with normoxic group. Hypoxic ischemic animals were treated one hour following HI and evaluated 48 h after. Our data showed that EPO significantly increased cell survival, associated with increased TIMP-1 activity, phosphorylation of JAK-2 and STAT-3, and decreased MMP-9 activity in vivo and in vitro. EPO's protective effects were reversed by inhibition of JAK-2 or TIMP-1 in both models. We concluded that JAK-2, STAT-3 and TIMP-1 are key mediators of EPO-induced neuroprotection during hypoxia ischemia injury.

Topics: Animals; Animals, Newborn; Blotting, Western; Cell Death; Cell Differentiation; Cerebral Infarction; Culture Media; Enzyme-Linked Immunosorbent Assay; Erythropoietin; Female; Gelatinases; Glucose; Hypoxia-Ischemia, Brain; Immunohistochemistry; Injections, Intraventricular; Matrix Metalloproteinase 9; Neuroprotective Agents; PC12 Cells; Pregnancy; Rats; Rats, Sprague-Dawley; Tissue Inhibitor of Metalloproteinase-1

Permanent mild-to-severe brain injury with neurologic sequelae remains a significant source of postoperative morbidity in cardiovascular surgery. There is increasing evidence that erythropoietin confers neuroprotective effects in various conditions of neuronal damage, such as hypoxia and cerebral ischaemia. Using a surviving porcine model, this study evaluates whether systemic treatment with erythropoietin induces brain protection in deep hypothermic circulatory arrest (DHCA).. Sixteen pigs (42+/-3 kg) randomly assigned into two groups (n=8) were subjected to 60 min of DHCA at an intracerebral temperature of 20 degrees C. The animals of the erythropietin group were treated perioperatively with 500 IU kg(-1) of recombinant human erythropoietin on 3 consecutive days beginning the day before surgery. Intracerebral monitoring was performed by subcortical microdialysis, brain tissue oxygenation, measurement of brain temperature and intracranial pressure. Neurologic recovery was evaluated daily. Perioperative S100 beta protein serum level was determined. The brains were harvested on the postoperative day 6 after perfusion fixation. Multiple brain regions were investigated histologically for hypoxic-ischaemic damage.. The subcortical brain microdialysis detected significant increase of glycerol and lactate concentrations in both groups (P=0.0001) with considerably higher concentrations in the brain of control animals (P=0.011). There were no significant differences in neurological outcome (P=0.15). Erythropoietin-treated animals tended to a more complete and rapid neurological recovery. By contrast, none of the animals in the control group achieved complete neurological recovery. S100 beta protein as a putative marker of cerebral injury tended to be higher in the control group. Brain infarction was detectable in all control animals but only in two erythropoietin-treated animals.. These results suggest some beneficial neuroprotective effects of erythropoietin in this model of global brain ischaemia induced by 1h of hypothermic circulatory arrest.

Topics: Animals; Brain; Disease Models, Animal; Drug Evaluation, Preclinical; Erythropoietin; Heart Arrest, Induced; Hemodynamics; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Intracranial Pressure; Neuroprotective Agents; Oxygen Consumption; Perioperative Care; Random Allocation; Recombinant Proteins; Sus scrofa

Neuronal replacement has recently gained attention as a potential therapeutic target under ischemic conditions. However, the oligodendrogenic infrastructure is equally critical for restoration of brain function and is also sensitive to ischemic injury. Erythropoietin (EPO) is a neuroprotective molecule that stimulates neuronal replacement after neonatal hypoxia/ischemia (H/I) when delivered soon after the onset of reperfusion. Because EPO can improve recovery of neurological function in the absence of tissue protection, we hypothesize that EPO may improve neurological function via enhancement of white matter recovery after H/I. Thus, we sought to determine the effects of delayed administration of EPO on white matter injury and recovery of neurological function after neonatal H/I.. EPO (1000 U/kg) was injected intraperitoneally at multiple time points beginning 48 hours after H/I in postnatal day 7 rats. The effects of EPO on oligodendrogenesis, white matter injury, and neurogenesis were evaluated using bromodeoxyuridine incorporation and cell-specific immunohistochemistry. Neurological function was assessed by sensorimotor behavioral tests.. Delayed administration of EPO was incapable of reducing brain volume loss but significantly increased oligodendrogenesis and maturation of oligodendrocytes and attenuated white matter injury after H/I. These effects occurred concurrently with enhanced neurogenesis. Delayed EPO treatment improved behavioral neurological outcomes 14 days after H/I injury.. Our study demonstrates that delayed administration of EPO promotes oligodendrogenesis and attenuates white matter injury concurrently with increased neurogenesis. These effects likely contribute to the observed improvement in neurological functional outcomes.

Topics: Animals; Animals, Newborn; Erythropoietin; Hypoxia-Ischemia, Brain; Neurogenesis; Neurons; Oligodendroglia; Rats; Rats, Sprague-Dawley; Recovery of Function

Topics: Animals; Asphyxia Neonatorum; Combined Modality Therapy; Erythropoietin; Humans; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Infant, Newborn; Magnesium Sulfate; Melatonin; Neuroprotective Agents; Recombinant Proteins

Erythropoietin (Epo) is an endogenous cytokine that regulates hematopoiesis and is widely used to treat anemia. In addition, it has recently increased interest in the neurosciences since the new concept of Epo as a neuroprotective agent has emerged. The potential protective effect of human recombinant Epo (r-hu-Epo) on a hypoxic-ischemic (HI) pup rat model was studied. Cerebral HI was obtained by permanent left carotid artery ligature of pups followed by a 2-h hypoxia. Three hours after carotid occlusion, brain lesions were assessed by magnetic resonance diffusion weighted imaging. Intraperitoneal administration of r-hu-Epo (30,000 U/kg dose) limited both the HI-induced brain lesion area and the decrease in apparent diffusion coefficient (ADC) in the lesion. To identify potential mechanisms underlying the effects of Epo, immunohistochemical detection of caspase-3 and water channel protein aquaporin-4 (AQP4) were performed. No early apoptosis was detected, but up-regulation of AQP4 expression was observed in HI pups that received r-hu-Epo compared with HI animals without treatment. This study demonstrates an early neuroprotective effect of Epo with regard to brain lesion area and ADC values. One possible mechanism of Epo for decreasing brain edema and cellular swelling could be a better clearance of water excess in brain tissue, a process possibly mediated by AQP4.

Topics: Animals; Animals, Newborn; Aquaporin 4; Brain; Disease Models, Animal; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Immunohistochemistry; Magnetic Resonance Imaging; Rats; Rats, Wistar; Recombinant Proteins

Erythropoietin (Epo), known to stimulate erythroid progenitor cell survival, proliferation, and differentiation, has been shown to be neuroprotective against brain ischemia in animal models. Both Epo and Epo receptor (EpoR) are expressed in the brain and are up-regulated by hypoxia. Brain Epo signaling can stimulate neural cell survival and prevent neuron apoptosis. Neurons from EpoR null mice exhibit marked increased sensitivity to hypoxia. In endothelial cells, Epo has been shown to stimulate nitric oxide (NO) production, particularly at low pO(2). We found here that the EpoR expression on neural cells and Epo's neuroprotective effect were regulated by NO. Hypoxia increased NO production as well as EpoR expression, and inhibition of NOS activity reduced the proportion of EpoR-expressing neurons induced at low pO(2). Conversely, addition of NO donor to cultures grown under normoxia induced EpoR. Similarly, NO donor increased EpoR promoter activity in a reporter gene assay, suggesting that NO regulates EpoR at the transcription level. Preincubation of neurons with NO results in induction of EpoR, which gives rise to protection against hypoxia even in the absence of exogenous Epo, although at high concentration NO is toxic. These data provide evidence of a role for NO in Epo activity in brain and suggest links between NO production, EpoR expression, and Epo signaling in neuroprotection.

Topics: Animals; Cells, Cultured; Cytoprotection; Erythropoietin; Gene Expression Regulation; Hypoxia-Ischemia, Brain; Ischemic Preconditioning; Mice; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; Neurons; Nitric Oxide; Receptors, Erythropoietin; Recombinant Proteins; Signal Transduction; Up-Regulation

Topics: Erythropoietin; Female; Fetal Diseases; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Infant, Premature, Diseases; Pregnancy

Brain injury from preterm birth predisposes children to cerebral palsy, epilepsy, cognitive delay, and behavioral abnormalities. The CNS injury often begins before the early birth, which hinders diagnosis and concurrent treatment. Safe, effective postnatal interventions are urgently needed to minimize these chronic neurological deficits. Erythropoietin (EPO) is a pleiotropic neuroprotective cytokine, but the biological basis of its efficacy in the damaged developing brain remains unclear. Coordinated expression of EPO ligand and receptor expression occurs during CNS development to promote neural cell survival. The authors propose that prenatal third trimester global hypoxia-ischemia disrupts the developmentally regulated expression of neural cell EPO signaling, and predisposes neural cells to death. Furthermore, the authors suggest that neonatal exogenous recombinant human EPO (rhEPO) administration can restore the mismatch of EPO ligand and receptor levels, and enhance neural cell survival.. Transient systemic hypoxia-ischemia (TSHI) on embryonic Day 18 in rats mimics human early-third trimester placental insufficiency. This model was used to test the authors' hypothesis using a novel clinically relevant paradigm of prenatal injury on embryonic Day 18, neonatal systemic rhEPO administration initiated 4 days after injury on postnatal Day 1, and histological, biochemical, and functional analyses in neonatal, juvenile, and adult rats.. The results showed that prenatal TSHI upregulates brain EPO receptors, but not EPO ligand. Sustained EPO receptor upregulation was pronounced on oligodendroglial lineage cells and neurons, neural cell populations particularly prone to loss from CNS injury due to preterm birth. Postnatal rhEPO administration after prenatal TSHI minimized histological damage and rescued oligodendrocytes and gamma-aminobutyric acidergic interneurons. Myelin basic protein expression in adult rats after insult was reduced compared with sham controls, but could be restored to near normal levels by neonatal rhEPO treatment. Erythropoietin-treated TSHI rats performed significantly better than their saline-treated peers as adults in motor skills tests, and showed significant seizure threshold restoration using a pentylenetetrazole increasing-dose paradigm.. These data demonstrate that neonatal rhEPO administration in a novel clinically relevant paradigm initiated 4 days after a global prenatal hypoxic-ischemic insult in rats rescues neural cells, and induces lasting histological and functional improvement in adult rats.

Topics: Animals; Blotting, Western; Cell Death; Erythropoietin; Fetal Diseases; Hypoxia-Ischemia, Brain; Immunohistochemistry; Ligands; Motor Skills; Neurons; Oligodendroglia; Rats; Rats, Sprague-Dawley; Receptors, Erythropoietin; Recombinant Proteins; Seizures

Topics: Animals; Animals, Newborn; Cell Proliferation; Erythropoietin; Humans; Hypoxia-Ischemia, Brain; Models, Animal; Oligodendroglia; Rats; Receptors, Erythropoietin; Treatment Outcome

In this study we prepared nanocarrier of erythropoietin (EPO) and the curative effect of the EPO-containing nanoparticles for periventricular leukomalacia (PVL) model was validated. It was demonstrated that EPO-containing nanoparticles can ameliorate drug-induced liquefaction caused by hypoxia. EPO-containing nanomedicine may open new therapeutic strategies in hypoxia cure.

Topics: Animals; Chromatography, High Pressure Liquid; Erythropoietin; Fluorescent Antibody Technique, Indirect; Hypoxia-Ischemia, Brain; Microscopy, Electron, Scanning; Nanoconjugates; Oligodendroglia; Rats; Rats, Sprague-Dawley

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

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

Recombinant human erythropoietin (rEpo) is neuroprotective in neonatal models of brain injury. Proposed mechanisms of neuroprotection include activation of gene pathways that decrease oxidative injury, inflammation, and apoptosis, while increasing vasculogenesis and neurogenesis. To determine the effects of rEpo on gene expression in 10-d-old BALB-c mice with unilateral brain injury, we compared microarrays from the hippocampi of brain-injured pups treated with saline or rEpo to similarly treated sham animals. Total RNA was extracted 24 h after brain injury and analyzed using Affymetrix GeneChip Mouse Exon 1.0 ST Arrays. We identified sex-specific differences in hippocampal gene expression after brain injury and after high-dose rEpo treatment using single-gene and gene set analysis. Although high-dose rEpo had minimal effects on hippocampal gene expression in shams, at 24-h post brain injury, high-dose rEpo treatment significantly decreased the proinflammatory and antiapoptotic response noted in saline-treated brain-injured comparison animals.

Topics: Animals; Animals, Newborn; Apoptosis; Disease Models, Animal; Erythropoietin; Female; Gene Expression Profiling; Gene Expression Regulation; Hippocampus; Humans; Hypoxia-Ischemia, Brain; Inflammation; Male; Mice; Mice, Inbred BALB C; Neuroprotective Agents; Oligonucleotide Array Sequence Analysis; Recombinant Proteins; Sex Factors; Time Factors

Inspired from preconditioning studies, ischemic postconditioning, consisting of the application of intermittent interruptions of blood flow shortly after reperfusion, has been described in cardiac ischemia and recently in stroke. It is well known that ischemic tolerance can be achieved in the brain not only by ischemic preconditioning, but also by hypoxic preconditioning. However, the existence of hypoxic postconditioning has never been reported in cerebral ischemia.. Adult mice subjected to transient middle cerebral artery occlusion underwent chronic intermittent hypoxia starting either 1 or 5 days after ischemia and brain damage was assessed by T2-weighted MRI at 43 days. In addition, we investigated the potential neuroprotective effect of hypoxia applied after oxygen glucose deprivation in primary neuronal cultures.. The present study shows for the first time that a late application of hypoxia (5 days) after ischemia reduced delayed thalamic atrophy. Furthermore, hypoxia performed 14 hours after oxygen glucose deprivation induced neuroprotection in primary neuronal cultures. We found that hypoxia-inducible factor-1alpha expression as well as those of its target genes erythropoietin and adrenomedullin is increased by hypoxic postconditioning. Further studies with pharmacological inhibitors or recombinant proteins for erythropoietin and adrenomedullin revealed that these molecules participate in this hypoxia postconditioning-induced neuroprotection.. Altogether, this study demonstrates for the first time the existence of a delayed hypoxic postconditioning in cerebral ischemia and in vitro studies highlight hypoxia-inducible factor-1alpha and its target genes, erythropoietin and adrenomedullin, as potential effectors of postconditioning.

Topics: Adrenomedullin; Animals; Atrophy; Brain; Cells, Cultured; Cytoprotection; Disease Models, Animal; Energy Metabolism; Erythropoietin; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; Hypoxia, Brain; Infarction, Middle Cerebral Artery; Male; Mice; Nerve Degeneration; Oxidative Stress; Time Factors

Neonatal stroke leads to mortality and severe morbidity, but there currently is no effective treatment. Erythropoietin (EPO) promotes cytoprotection and neurogenesis in the short term following brain injury; however, long-term cognitive outcomes and optimal dosing regimens have not been clarified. We performed middle cerebral artery occlusion in postnatal day 10 rats, which were treated with either a single dose of EPO (5 U/g, i.p.) immediately upon reperfusion, or 3 doses of EPO (1 U/g, i.p. each) at 0 h, 24 h, and 7 days after injury. At 3 months after injury, rats treated with 3 doses of EPO did not differ from shams in the Morris water maze, and generally performed better than either rats treated with a single dose or vehicle-treated injured rats. These multiple-dose-treated rats also had increases in hemispheric volume and its subregions. These results suggest that additional, later doses of EPO may be required for cell repair, proliferation, and long-term incorporation into neural networks after neonatal brain injury.

Topics: Animals; Animals, Newborn; Brain; Cognition; Cytoprotection; Erythropoietin; Exploratory Behavior; Hypoxia-Ischemia, Brain; Infarction, Middle Cerebral Artery; Magnetic Resonance Imaging; Maze Learning; Memory; Neurons; Organ Size; Rats; Rats, Sprague-Dawley; Spatial Behavior

The aim of this study was to investigate the effect of erythropoietin (EPO) on histological brain injury, subventricular zone (SVZ) expansion, and sensorimotor function deficits induced by hypoxia-ischemia (HI) in newborn rat pups. Seven-day-old male rat pups were divided into six groups: normoxia control, normoxia EPO, hypoxia control, hypoxia EPO, HI control, and HI EPO group. Sham surgery or HI was performed in all animals. HI was induced by ligation of the right common carotid artery followed by 90 min of hypoxia with 8% oxygen. Recombinant human EPO 3 U/g or saline was administered intraperitoneally, immediately, at 24- and 48-hr after insult. At two weeks after insult, animals were challenged with cylinder-rearing test for evaluating forelimb asymmetry to determine sensorimotor function. All animals were then sacrificed for volumetric analysis of the cerebral hemispheres and the SVZ. The saline-treated HI rats showed marked asymmetry by preferential use of the non-impaired, ipsilateral paw in the cylinder-rearing test. Volumetric analysis of brains revealed significantly decreased preserved ipsilateral hemispheric volume and increased ipsilateral SVZ volume compared with the sham-operated animals. Treatment of EPO significantly improved forelimb asymmetry and preserved ipsilateral hemispheric volume along with decreased expansion of ipsilateral SVZ following HI compared to the saline-treated HI rats. These results support the use of EPO as a candidate drug for treatment of neonatal hypoxic-ischemic brain damage.

Topics: Animals; Animals, Newborn; Carotid Artery, Common; Cerebral Ventricles; Erythropoietin; Female; Hypoxia-Ischemia, Brain; Ligation; Male; Motor Activity; Pregnancy; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Recovery of Function

One of the pathological hallmarks of periventricular leukomalacia (PVL) is the selective vulnerability of late oligodendrocyte progenitors (preoligodendrocytes; preOLs) to hypoxia-ischemia (H-I). It is unknown whether recombinant human erythropoietin (rhEPO) protects preOLs in vivo.. To develop a rat PVL model in which preOLs are selectively damaged and exhibit similar pathological changes to diffuse-type human PVL, various conditions of H-I were compared in P2-P7 rats (P2 = postnatal day 2). To evaluate the effect of rhEPO on oligoprotection (preOLs), rhEPO was administered to P3 PVL rats.. After counts of NG2-positive and O4-positive cells were performed in P2-P7 rats, right common carotid artery occlusion followed by 6% O(2) for 0-120 min was performed in P2-P4 rats. The mortality and histological alterations after hematoxylin/eosin staining and ED1 immunostaining were assessed 2 days after H-I. Various doses of rhEPO (1-30,000 U/kg i.p.) were administered to PVL rats 15 min before administration of 6% O(2).. Double-positive cells for NG2 and O4 were detected from P2, and their number gradually increased until P7. Although right common carotid artery occlusion with 6% O(2) for 60 min resulted in a relatively high proportion of deaths in P2-P4 rats, typical histological changes in the PVL diffuse component were found in most surviving P3 animals. With 50-100 U/kg rhEPO, the histological damage was attenuated.. Histological changes similar to those seen in the PVL diffuse component were induced by H-I in P3 rats, in which preOLs were gradually developing, and a low dose of rhEPO was effective in the treatment of brain damage induced by H-I.

Topics: Animals; Animals, Newborn; Antigens; Disease Models, Animal; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Hypoxia, Brain; Immunohistochemistry; Infant, Newborn; Leukomalacia, Periventricular; Oligodendroglia; Pregnancy; Proteoglycans; Rats; Rats, Wistar; Stem Cells

Hypoxic-ischemic damage is a major challenge for neuronal tissue. In the present study, we investigated the effects of anoxia and glucose deprivation on adult neural stem cells (NSCs) in vitro. We assessed glucose deprivation, anoxia and the combination of the latter separately. After 24 h of anoxia, cell numbers increased up to 60% compared to normoxic controls. Whereas nearly all normoxic cells incorporated the mitotic marker BrdU (99%), only 85% of the anoxic cells were BrdU-positive. Counting of interphase chromosomes showed 8-fold higher cell division activity after anoxia. The number of necrotic cells doubled after anoxia (14% compared to 7% after normoxia). Apoptosis was measured by two distinct caspases assays. Whereas the total caspase activity was reduced after anoxia, caspase 3/7 showed no alterations. Glucose deprivation and oxygen glucose deprivation both reduced cell viability by 56 and 53%, respectively. Under these conditions, total caspases activity doubled, but caspase 3/7 activity remained unchanged. Erythropoietin, which was reported as neuroprotective, did not increase cell viability in normoxia, but moderately under oxygen glucose deprivation by up to 6%. Erythropoietin reduced total caspase activity by nearly 30% under all the conditions, whereas caspase 3/7 activity was not affected. Our results show that anoxia increases proliferation and viability of adult NSCs, although a fraction of NSCs does not divide during anoxia. In conclusion, anoxia increased cell viability, cell number and proliferation in NSCs from the rat brain. Anoxia turned out to be a highly stimulating environmental for NSCs and NSCs died only when deprived of glucose. We conclude that the availability of glucose but not of oxygen is a crucial factor for NSC survival, regulating apoptotic pathways via caspases activity other than the caspases 3/7 pathway. Therefore, we conclude that NSCs are dying from glucose deprivation, not from hypoxic-ischemic damage.

Topics: Animals; Apoptosis; Bromodeoxyuridine; Caspases; Cell Count; Cell Differentiation; Cell Hypoxia; Cell Proliferation; Cell Survival; Cells, Cultured; Erythropoietin; Glucose; Hypoxia-Ischemia, Brain; Male; Mitosis; Necrosis; Neuronal Plasticity; Neurons; Neuroprotective Agents; Rats; Rats, Wistar; Recovery of Function; Signal Transduction; Stem Cells

To investigate whether desferoxamine (DFO) preconditioning can induce tolerance against cerebral ischemia and its effect on the expression of hypoxia inducible factor 1alpha (HIF-1alpha) and erythropoietin (EPO) in vivo and in vitro.. Rat model of cerebral ischemia was established by middle cerebral artery occlusion with or without DFO administration. Infarct size was examined by TTC staining, and the neurological severity score was evaluated according to published method. Cortical neurons were cultured under ischemia stress which was mimicked by oxygen-glucose deprivation (OGD), and the neuron damage was assessed by MTT assay. Immunofluorescent staining was employed to detect the expressions of HIF-1alpha and EPO.. The protective effect induced by DFO (decreasing the infarction volume and ameliorating the neurological function) appeared at 2 d after administration of DFO (post-DFO), lasted until 7 d and disappeared at 14 d (P < 0.05); the most effective action was observed at 3 d post-DFO. DFO induced tolerance of cultured neurons against OGD: neuronal viability was increased 23%, 34%, 40%, 48% and 56% at 8 h, 12 h, 24 h, 36 h, and 48 h, respectively, post-DFO (P < 0.05). Immunofluorescent staining found that HIF-1alpha and EPO were upregulated in the neurons of rat brain at 3 d and 7 d post-DFO; increase of HIF-1alpha and EPO appeared in cultured cortex neurons at 36 h and 48 h post-DFO.. DFO induced tolerance against focal cerebral ischemia in rats, and exerted protective effect on OGD cultured cortical neurons. DFO significant induced the expression of HIF-1alpha and EPO both in vivo and in vitro. DFO preconditioning can protect against cerebral ischemia, which may be associated with the synthesis of HIF-1alpha and EPO.

Topics: Animals; Brain Ischemia; Cells, Cultured; Cerebral Infarction; Deferoxamine; Disease Models, Animal; Erythropoietin; Fluorescent Antibody Technique; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; Infarction, Middle Cerebral Artery; Iron; Ischemic Preconditioning; Nerve Degeneration; Neurons; Rats; Rats, Sprague-Dawley; Siderophores; Time Factors; Treatment Outcome; Up-Regulation

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

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

High-dose recombinant erythropoietin (rEpo) is neuroprotective in neonatal animal models of brain injury, but the long-term consequences of neonatal exposure have not been studied.. We hypothesized that multiple injections of high-dose rEpo during the neonatal period would be safe, and would improve neurologic outcomes after exposure to neonatal hypoxia or hypoxic-ischemic injury.. Three experimental groups of Sprague-Dawley rats were assessed: (1) normoxia, (2) hypoxia and (3) hypoxia-ischemia. Groups 1 and 2 were given 0, 2,500 or 5,000 U/kg rEpo subcutaneously for the first 5 days of life (P1-P5). Group 2 animals also underwent 2 h of hypoxia (8% O(2)) daily from P1-P3. Group 3 animals underwent right carotid artery ligation followed by hypoxia (8% O(2) x 90 min) on P7, followed by either vehicle or rEpo (2,500 U/kg subcutaneously QD x3). We evaluated short- and long-term physiologic and behavioral outcomes. Major organs were evaluated grossly and histologically.. rEpo treatment transiently raised hematocrit, prevented hypoxia-induced delays in geotaxis and growth, improved forelimb strength, promoted liver growth in males, lowered the adult platelet count, but did not alter other CBC indices or histology. rEpo prevented hypoxia-ischemia-induced learning impairment and substantia nigra neuron loss.. Repeated treatment of newborn rats with high-dose rEpo was safe under all conditions tested. rEpo treatment improved the development of hypoxia-exposed newborns and prevented the learning impairment and dopamine neuron loss due to unilateral hypoxic-ischemic brain injury.

Topics: Animals; Animals, Newborn; Avoidance Learning; Behavior, Animal; Brain; Dopamine; Drug-Related Side Effects and Adverse Reactions; Erythropoietin; Hematocrit; Hypoxia; Hypoxia-Ischemia, Brain; Liver; Models, Animal; Neurons; Neuroprotective Agents; Organ Size; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Weight Gain

Recombinant human erythropoietin (rEpo) is neuroprotective in neonatal models of hypoxic-ischemic brain injury. However, the optimal rEpo dose, dosing interval, and number of doses for reducing brain injury are still undetermined. We compared the neuroprotective efficacy of several subcutaneous rEpo treatment regimens. Seven-day-old rats underwent unilateral carotid ligation plus 90 min 8% hypoxia. Treatment began immediately after injury. Treatment regimens examined included 1, 3, or 7 daily subcutaneous injections of either 0 (vehicle), 2,500, 5,000, or 30,000 U/kg rEpo. Gross brain injury, neuronal apoptosis (TUNEL), and gliosis (glial fibrillary acidic protein) were assessed at 48 h or 1 wk post injury. Immunoreactive cells and brain injury were quantified for statistical comparison to vehicle controls. rEpo treatment reduced brain injury, apoptosis, and gliosis, in a dose-dependent U-shaped manner at both 48 h and 1 wk. Neither one injection of 2,500, seven injections of 5,000, or three injections of 30,000 U/kg rEpo were protective. Three doses of 5,000 and one dose of 30,000 U/kg rEpo were most protective at both time intervals. rEpo provides dose-dependent neuroprotection. Of the regimens tested, three doses of 5,000 U/kg was optimal because it provided maximal benefit with limited total exposure.

Topics: Animals; Animals, Newborn; Brain; Dose-Response Relationship, Drug; Drug Administration Schedule; Erythropoietin; Hypoxia-Ischemia, Brain; Random Allocation; Rats; Recombinant Proteins

Erythropoietin (Epo) and its receptor (EpoR), critical for erythropoiesis, are expressed in the nervous system. Prior to death in utero because of severe anemia EpoR-null mice have fewer neural progenitor cells, and differentiated neurons are markedly sensitive to hypoxia, suggesting that during development Epo stimulates neural cell proliferation and prevents neuron apoptosis by promoting oxygen delivery to brain or by direct interaction with neural cells. Here we present evidence that neural progenitor cells express EpoR at higher levels compared with mature neurons; that Epo stimulates proliferation of embryonic neural progenitor cells; and that endogenous Epo contributes to neural progenitor cell proliferation and maintenance. EpoR-null mice were rescued with selective EpoR expression driven by the endogenous EpoR promoter in hematopoietic tissue but not in brain. Although these mice exhibited normal hematopoiesis and erythrocyte production and survived to adulthood, neural cell proliferation and viability were affected. Embryonic brain exhibited increased neural cell apoptosis, and neural cell proliferation was reduced in the adult hippocampus and subventricular zone. Neural cells from these animals were more sensitive to hypoxia/glutamate neurotoxicity than normal neurons in culture and in vivo. These observations demonstrate that endogenous Epo/EpoR signaling promotes cell survival in embryonic brain and contributes to neural cell proliferation in adult brain in regions associated with neurogenesis. Therefore, Epo exerts extra-hematopoietic function and contributes directly to brain development, maintenance, and repair by promoting cell survival and proliferation independent of insult, injury, or ischemia.

Topics: Animals; Apoptosis; Brain; Cell Differentiation; Cell Hypoxia; Cell Proliferation; Cell Survival; Erythropoiesis; Erythropoietin; Hypoxia-Ischemia, Brain; Mice; Mice, Mutant Strains; Neurons; Organ Specificity; Promoter Regions, Genetic; Receptors, Erythropoietin; Signal Transduction; Stem Cells

Erythropoietin (EPO) has been well characterized and shown to improve functional outcomes after ischemic injury, but EPO may also have unexplored effects on neurovascular remodeling and neuronal replacement in the neonatal ischemic brain. The current study investigates the effects of exogenous administration of EPO on revascularization and neurogenesis, 2 major events thought to contribute to neuronal replacement, in the neonatal brain after hypoxia/ischemia (H/I).. Seven-day-old rat pups were treated with recombinant human EPO or vehicle 20 minutes after H/I and again on postischemic days 2, 4, and 6. Rats were euthanized 7 or 28 days after H/I for evaluation of infarct volume, revascularization, neurogenesis, and neuronal replacement using bromodeoxyuridine incorporation, immunohistochemistry, and lectin labeling. Neurological function was assessed progressively for 28 days after H/I by gait testing, righting reflex and foot fault testing.. We demonstrate that exogenous EPO-enhanced revascularization in the ischemic hemisphere correlated with decreased infarct volume and improved neurological outcomes after H/I. In addition to vascular effects, EPO increased both neurogenesis in the subventricular zone and migration of neuronal progenitors into the ischemic cortex and striatum. A significant number of newly synthesized cells in the ischemic boundary expressed neuronal nuclei after EPO treatment, indicating that exogenous EPO led to neuronal replacement.. Our data suggest that treatment with EPO contributes to neurovascular remodeling after H/I by promoting tissue protection, revascularization, and neurogenesis in neonatal H/I-injured brain, leading to improved neurobehavioral outcomes.

Topics: Animals; Animals, Newborn; Behavior, Animal; Cell Division; Cell Movement; Cerebrovascular Circulation; Erythropoietin; Hypoxia-Ischemia, Brain; Neovascularization, Physiologic; Neurons; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Recovery of Function

Our objective was to establish a nonhuman primate model of perinatal asphyxia appropriate for preclinical evaluation of neuroprotective treatment strategies under conditions that closely resemble human neonatal emergencies, and to begin testing the safety and efficacy of erythropoietin neuroprotective treatment. Prior to delivery by hysterotomy, the umbilical cords of near term Macaca nemestrina (n = 8) were clamped for times ranging between 12 and 15 min. Animals received erythropoietin (5,000 U/kg/dose x 2 i.v., n = 3), or vehicle (n = 5) after resuscitation. We assessed physiologic parameters, continuous electroencephalogram, magnetic resonance imaging/spectroscopy, safety parameters and behavior. Animals were euthanized at 4 months of age. Mean birth weight was 507 +/- 62 g. Initial arterial pH ranged from 6.75 to 7.12, with base deficits of 17-25 mEq. Animals were flaccid at birth, with attenuated electroencephalograms, and seizures occurred in 3 of 8 animals. We demonstrated magnetic resonance imaging/spectroscopy changes consistent with hypoxia (elevated lactate levels were present in some animals), significant motor and behavioral abnormalities (particularly with 15 min of cord clamping), and evidence of gliosis at the time of death. We have established a reproducible model of moderate to severe perinatal hypoxic-ischemic injury in M. nemestrina newborns. This model, which combines structural, biochemical, and behavioral assessments over time can be used to assess the safety and efficacy of neuroprotective strategies.

Topics: Animals; Animals, Newborn; Asphyxia; Brain; Disease Models, Animal; Electroencephalography; Erythropoietin; Female; Fetal Monitoring; Gliosis; Hypoxia-Ischemia, Brain; Lactic Acid; Macaca nemestrina; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Neuroprotective Agents; Placental Circulation; Pregnancy; Seizures; Umbilical Cord

Perinatal asphyxia is an important cause of neonatal mortality and subsequent serious sequelae such as motor and cognitive deficits and seizures. The ameliorative effect of erythropoietin (Epo) on experimental hypoxic-ischemic brain injury in neonatal rats has been recently reported. Recent studies also confirm the antiapoptotic effect of Epo in a variety of in vitro and in vivo neuronal injury models including hypoxic-ischemic brain injury. However, molecular mechanisms of Epo protection and antiapoptotic effect in this model are unclear. Epo may exert its antiapoptotic effect via the differential regulation of the expression of genes involved in the apoptotic process.. Thus, in the present study, we studied the effects of systemically administered Epo on antiapoptotic (bcl-2, bcl-XL), proapoptotic (bax and DP5) gene expression following hypoxic-ischemic brain injury in neonatal rats.. Seven- day-old Wistar rat pups were divided into three groups: control group (n=15), saline-treated group (n=17), and Epo-treated group (n=18). Rat pups were subjected to left carotid artery occlusion followed by 2.5 h of hypoxic exposure. Epo-treated group received an intraperitoneal injection of recombinant human Epo at a dose of 1,000 units/kg, saline-treated group received an intraperitoneal injection of saline at the same volume of Epo. Forty-eight hours after hypoxia, 3 animals in each group were killed for histopathological evaluation. To detect DNA fragmentation in cell nuclei, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling reaction was applied. Bcl-2 and bax protein expression were also analyzed with immunohistochemistry. For reverse transcriptase-polymerase chain reaction (RT-PCR) analysis, rats were sacrificed 4, 12, and 24 h after hypoxia. Bcl-2, bcl-XL, bax, and DP5 mRNA expression were analyzed by RT-PCR.. Epo significantly prevented hypoxia-ischemia-induced bax and DP5 mRNA upregulation in brain tissue. Epo did not show any effect on bcl-XL transcription altered by injury. However, Epo reversed injury-induced downregulation in bcl-2 transcription. Modulating effects of Epo on bcl-2 and bax protein expression were also revealed by immunohistochemistry.. These results suggest that Epo exerts a neuroprotective effect against hypoxic-ischemic brain injury, at least partially, via the differential regulation of the expression of genes involved in apoptotic process.

Topics: Animals; Animals, Newborn; Apoptosis Regulatory Proteins; bcl-2-Associated X Protein; Erythropoietin; Gene Expression; Humans; Hypoxia-Ischemia, Brain; Immunohistochemistry; Neuropeptides; Neuroprotective Agents; Rats; Rats, Wistar; Recombinant Proteins; RNA, Messenger

Neonatal hypoxia-ischemia (HI) is a common cause of brain damage and subsequent behavioral deficits in premature/term infants. Rapid auditory processing deficits have been suggested to play a role in later language impairments in this population. We have previously shown auditory deficits in rats with neonatal HI injury and now report novel effects of behavioral sparing and neuroprotection following treatment with a low dose of Erythropoietin using this HI injury model.

Topics: Acoustic Stimulation; Analysis of Variance; Animals; Animals, Newborn; Discrimination, Psychological; Erythropoietin; Hypoxia-Ischemia, Brain; Male; Neuroprotective Agents; Rats; Rats, Wistar; Recombinant Proteins; Reflex, Acoustic; Time Factors

In the ischemic or hypoxic brain, astrocytes appear to be one of the main sources of erythropoietin (EPO). In this study, we investigated the differential contribution of hypoxia inducible factor (HIF) isoforms to the regulation of hypoxic EPO expression in cultured astrocytes. In addition, using an in vitro model of oxygen-glucose deprivation (OGD), we studied the role of HIF-1alpha and HIF-2alpha in the generation of paracrine protective signals by astrocytes that modulate the survival of neurons exposed to OGD. Expression of HIF-1alpha or HIF-2alpha was abrogated by infecting astrocytes with lentiviral particles encoding small interference RNA specific for HIF-1alpha or HIF-2alpha (siHIF-1alpha or siHIF-2alpha). Astrocytes infected with siHIF-1alpha showed abrogated hypoxic induction of vascular endothelial growth factor (VEGF) and lactate dehydrogenase (LDH) but normal EPO induction. In contrast, reduction of HIF-2alpha expression by siHIF-2alpha led to a drastic decrease of EPO hypoxic expression, but it did not affect LDH or VEGF upregulation. To further test whether HIF-2 is sufficient to drive EPO upregulation, we expressed oxygen-insensitive mutant forms of HIF-1alpha (mtHIF-1alpha) (P402A/P577A) and HIF-2alpha (mtHIF-2alpha) (P405A/P530A). Expression of mtHIF-2alpha but not mtHIF-1alpha in normoxic astrocytes resulted in a significant upregulation of EPO mRNA and protein. Accordingly, HIF-2alpha but not HIF-1alpha was found to be associated with the EPO hypoxia-response element by a chromatin immunoprecipitation assay. Interestingly, conditioned medium from astrocytes challenged by sublethal OGD improved neuronal survival to OGD; however, this effect was abolished during the downregulation of astrocytic HIF-2alpha using siHIF-2alpha. These results indicate that HIF-2alpha mediates the transcriptional activation of EPO expression in astrocytes, and this pathway may promote astrocytic paracrine-dependent neuronal survival during ischemia.

Topics: Animals; Astrocytes; Cell Survival; Cells, Cultured; Cerebral Cortex; Down-Regulation; Erythropoietin; Genetic Vectors; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; L-Lactate Dehydrogenase; Mice; Mice, Inbred C57BL; Mice, Knockout; Mutation; Oxygen; Paracrine Communication; Response Elements; Transcription Factors; Transcriptional Activation; Transfection; Up-Regulation; Vascular Endothelial Growth Factor A

We have previously shown that erythropoietin (Epo) exerts neuroprotective effects in the Rice-Vannucci model of neonatal hypoxic-ischemic brain injury. However, the mechanisms of Epo protection in this model are still unclear.. In the present study, we studied the effects of systemically administered Epo on lipid peroxidation levels and antioxidant enzyme (superoxide dismutase and glutathione peroxidase) activities following hypoxic-ischemic brain injury in neonatal rats.. Seven-day-old Wistar rat pups were subjected to left carotid artery occlusion followed by 2.5 h of hypoxic exposure. Brain lipid peroxidation levels and antioxidant enzyme activities were measured in the injured hemispheres 24 h after the hypoxic-ischemic insult.. Hypoxic-ischemic injury significantly increased the thiobarbituric acid-reactive substance levels in the injured hemispheres as compared to the control group. In addition, glutathione peroxidase activity was significantly elevated in Epo-treated animals compared to saline-treated animals and the control group.. These results suggest that Epo exerts neuroprotective effects against hypoxic-ischemic brain injury at least partially via the modulation of antioxidant enzyme activity.

Topics: Animals; Animals, Newborn; Brain; Erythropoietin; Glutathione Peroxidase; Hypoxia-Ischemia, Brain; Lipid Peroxidation; Rats; Rats, Wistar; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances

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

Perinatal asphyxia accounts for behavioral dysfunctions that often manifest as sensorimotor, learning or memory disabilities throughout development and into maturity. Erythropoietin (Epo) has been shown to exert neuroprotective effects in different models of brain injury including experimental models of perinatal asphyxia. However, the effect of Epo on functional abilities following cerebral hypoxia-ischemia (HI) in neonatal rats is not known. The aim of the present study is to investigate the effect of Epo on sensorimotor deficits and brain injury induced by hypoxia-ischemia. Seven-day-old rats underwent unilateral, permanent carotid artery ligation followed by 1 h of hypoxia. Epo was administered as a single dose immediately after the hypoxic insult (2000 U/kg). The neuroprotective effect of Epo was evaluated at postnatal day 42 by using a battery of behavioral tests and histological analysis. The results of the present study suggest that Epo treatment immediately after HI insult significantly facilitated recovery of sensorimotor function. Consistently, histopathological evaluation demonstrated that Epo significantly attenuated brain injury and preserved the integrity of cerebral cortex. These findings indicate that long-term neuroprotective effect of Epo on neonatal HI-induced brain injury might be associated with the preservation of sensorimotor functions.

Topics: Animals; Animals, Newborn; Cerebral Cortex; Cerebral Infarction; Disease Models, Animal; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Ligation; Male; Movement Disorders; Neuroprotective Agents; Rats; Rats, Wistar; Recovery of Function; Sensation Disorders; Treatment Outcome

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

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

Erythropoietin (EPO), a hematopoietic growth factor, has been shown to be neuroprotective when administered as either a pretreatment or posttreatment. This study tested the hypothesis that one of the mechanisms of protection afforded by posttreatment with recombinant human EPO (rh-EPO) is an anti-inflammatory effect via inhibition of interleukin (IL)-1beta.. Seven-day-old rat pups were subjected to unilateral carotid artery ligation followed by 90 minutes of hypoxia (8% O2 at 37 degrees C). Pups were divided into the following groups: control, hypoxia/ischemia, and hypoxia/ischemia plus rh-EPO. In the rh-EPO-treated pups, rh-EPO (5 U/g body weight IP) was administered starting 24 hours after the insult and then for 2 additional days. Samples were collected at 3, 7, 14, and 21 days after the insult. IL-1beta mRNA and protein levels were determined by quantitative real-time reverse transcription-polymerase chain reaction and ELISA. Tumor necrosis factor (TNF)-alpha mRNA levels were determined by colorimetric microplate assay.. rhEPO attenuated brain injury, as assessed by brain weight, and attenuated both the hypoxia/ischemia-induced increases in IL-1beta mRNA and protein levels. TNF-alpha mRNA levels did not increase at 3 to 14 days after the hypoxic/ischemic insult.. Administration of exogenous rh-EPO starting 24 hours after a hypoxic/ischemic insult is neuroprotective in the neonatal rat. This neuroprotective activity prevented the secondary, delayed rise in IL-1beta and attenuated the infiltration of leukocytes into the ipsilateral hemisphere.

Topics: Animals; Animals, Newborn; Brain; Carotid Arteries; Erythropoietin; Growth Substances; Humans; Hypoxia; Hypoxia-Ischemia, Brain; Inflammation; Interleukin-1; Ischemia; Leukocytes; Organ Size; Oxygen; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Reverse Transcriptase Polymerase Chain Reaction; RNA; RNA, Messenger; Temperature; Time Factors

Brain injury as a result of hypoxia-ischemia remains a common cause of morbidity and mortality in neonates. No effective therapy is currently available. The hematopoietic cytokine erythropoietin (Epo) provides neuroprotection in many adult models of brain injury and is currently being investigated as a therapeutic agent for human stroke and spinal cord injury. We tested the hypothesis that recombinant Epo (rEpo) would improve neurobehavioral outcomes after neonatal hypoxic-ischemic brain injury. Postnatal day 7 rats underwent right common carotid artery occlusion followed by a 90-min exposure to 8% oxygen. Rats were subsequently treated with rEpo or placebo. Sensory neglect and apomorphine-induced rotation were measured at P27 and P28. Rats were killed at P30, blood was drawn, and the brains were perfusion-fixed for histology and immunohistochemistry. No differences in gross brain injury between rEpo and placebo-treated rats were found. Neonatal rEpo treatment protected dopamine neurons as indicated by the preservation of tyrosine hydroxylase-positive cells in the substantia nigra pars compacta and ventral tegmental area. rEpo treatment also improved functional outcomes by reducing sensory neglect and preventing the rotational asymmetry seen in control animals. No differences in hematocrit, white blood cell counts, neutrophil counts, or platelet counts were measured. We observed that rEpo treatment protected mesencephalic dopamine neurons and reduced the degree of behavioral asymmetries at 4 wk of life. On the basis of these findings, we conclude that further studies investigating the safety and efficacy of high-dose rEpo as a neuroprotective strategy are indicated in neonatal models of hypoxic-ischemic brain injury.

Topics: Animals; Animals, Newborn; Apomorphine; Behavior, Animal; Brain; Cell Nucleus; Dopamine; Erythropoietin; Hypoxia-Ischemia, Brain; Immunohistochemistry; Neurons; Neuroprotective Agents; Neutrophils; Rats; Rats, Sprague-Dawley; Recombinant Proteins; 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) exerts neuroprotection against neuronal death induced by ischemia and hypoxia in vitro and in vivo. Recent studies suggest that the neuroprotective effects of Epo may depend upon different mechanisms, including the inhibition of nitric oxide (NO). We recently demonstrated that Epo exerts neuroprotection in a model of neonatal hypoxic-ischemic brain damage. In the present study, we directly determined whether systemic administration of recombinant Epo modulates cerebral NO production in a neonatal rat model of hypoxic-ischemic brain injury. Seven-day-old Wistar rat pups were subjected to left carotid artery occlusion followed by 2.5 h of hypoxic exposure. Brain nitrite levels were evaluated in both hemispheres (carotid ligated or nonligated) by Griess reagent 72 h after the hypoxic-ischemic insult. Our results show that hypoxic-ischemic insult results a significant increase in NO production as compared with NO levels in hypoxic hemispheres and control animals. A single dose of Epo treatment (1,000 U/kg i.p.) significantly decreased NO overproduction in the hypoxic-ischemic hemisphere, whereas no significant change appeared in hypoxia alone or in controls. These data suggest that the selective inhibitory effect of Epo on NO overproduction could have a neuroprotective effect in neonatal hypoxic-ischemic brain injury.

Topics: Animals; Brain Chemistry; Brain Diseases; Carotid Arteries; Disease Models, Animal; Erythropoietin; Hypoxia; Hypoxia-Ischemia, Brain; Ligation; Nitric Oxide; Nitrites; Rats; Rats, Wistar; Recombinant Proteins

Hypoxic-ischemic (H-I) encephalopathy is a major contributor to morbidity and mortality in infants and children. To delineate the nature and mechanism(s) of neuroprotection via erythropoietin (EPO) gene therapy, we evaluated the effects of single intravenous injection of naked plasmid DNA encoding EPO in H-I infant rats. Single administration of naked plasmid containing EPO cDNA driven under cytomegalovirus promoter (pCMV-EPO) by rapid injection via the tail vein produced a remarkable level of human EPO protein in the circulation, peaking at one day and lasting for 14 days after injection. There were significant improvements of water maze task in H-I rats after EPO gene therapy. Our data showed that the mechanisms of EPO gene therapy were rescue of CA1 neurons from lethal H-I injury, prevention of neuronal apoptosis in CA1 region, and decrease of glial activation in corpus callosum. This could be the first report of successful treatment of H-I injury by a single intravenous infusion of EPO gene.

Topics: Animals; DNA; Enzyme-Linked Immunosorbent Assay; Erythropoietin; Gene Expression; Genetic Therapy; Hippocampus; Hypoxia-Ischemia, Brain; Male; Maze Learning; Plasmids; Rats; Rats, Sprague-Dawley

It is well known that neonatal hypoxic-ischemic brain injury leads to mental retardation and deficits in cognitive abilities such as learning and memory in human beings. The ameliorative effect of erythropoietin (Epo) on experimental hypoxic-ischemic brain injury in neonatal rats has been recently reported. However, the effect of Epo on cognitive abilities in the hypoxic-ischemic brain injury model is unknown. The aim of this study is to investigate the effects of Epo on learning-memory, behavior and neurodegeneration induced by hypoxia-ischemia. Seven days old Wistar Albino rat pups have been used in the study (n = 28). Experimental groups in the study were: (1) saline-treated hypoxia-ischemia group, (2) Epo-treated (i.p., 1000 U/kg) hypoxia-ischemia group, (3) sham-operated group, (4) control group. In hypoxia-ischemia groups, left common carotid artery was ligated permanently on the seventh postnatal day. Two hours after the procedure, hypoxia (92% nitrogen and 8% oxygen) was induced for 2.5 h. Epo was administered as a single dose immediately after the hypoxia period. When pups were 22 days old, learning experiments were performed using Morris water maze. On the 20th week, when brain development is accepted to be complete, learning experiments were repeated. Rats were then perfused and brains removed for macroscopic and microscopic evaluation. Epo treatment immediately after hypoxic-ischemic insult significantly improved long-term neurobehavioral achievements when tested during the subsequent phase of brain maturation and even into adulthood. Histopathological evaluation demonstrated that Epo also significantly diminished brain injury and spared hippocampal CA1 neurons. In conclusion, Epo administrated as a single dose immediately after neonatal hypoxic-ischemic insult provides benefit over a prolonged period in the still developing rat brain. Since the wide use of Epo in premature newborns, this agent may be potentially beneficial in treating asphyxial brain damage in the perinatal period.

Topics: Analysis of Variance; Animals; Animals, Newborn; Behavior, Animal; Brain Injuries; Cell Count; Erythropoietin; Escape Reaction; Functional Laterality; Hippocampus; Hypoxia-Ischemia, Brain; Maze Learning; Memory Disorders; Neurons; Rats; Rats, Wistar; Reaction Time; Spatial Behavior; Time Factors

Erythropoietin (EPO) prevents neuronal damage following ischemic, metabolic and excitotoxic stress. Recent studies have shown that EPO plays a significant role in the developing brain. The present study investigates the effect of EPO administration on hypoxic-ischemic brain injury and the possibility that its neuroprotective action may be associated with anti-apoptotic activity. Seven-day-old rats were treated with EPO (2000 U/kg) and subjected to a modified Levine procedure. EPO administration before the hypoxic-ischemic insult significantly reduces the severity of brain damage and improved the short-term functional brain recovery. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling and DNA electrophoresis displayed no evidence of DNA fragmentation in EPO-treated animals. These results suggest that EPO might protect the neonatal rat brain by anti-apoptotic mechanisms.

Topics: Animals; Animals, Newborn; Asphyxia Neonatorum; Brain; Disease Models, Animal; DNA Fragmentation; Erythropoietin; Female; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Male; Neuroprotective Agents; Rats; Rats, Wistar; Reflex

Erythropoietin (EPO), known for its role in erythroid differentiation, has been suggested to have non-hematopoietic functions in the brain, especially during development. In the present study, we investigated the expression of erythropoietin and erythropoietin receptor (EPOR) in the developing rat brain following hypoxia-ischemia. Seven-day-old rats underwent unilateral, permanent carotid artery ligation followed by 1 h of hypoxia, and their brains were examined immediately, 24 h or 4 days after hypoxia-ischemia. RT-PCR and Western blot analysis revealed that hypoxia-ischemia only marginally affected EPO expression. Immunohistochemical study of brains 4 days after hypoxia showed that 60 min of hypoxia (resulting in cortical infarction and severe neuronal loss in other regions) led to the increased EPO immunoreactivity, especially in the boundaries of the damaged cerebral cortex, associated with astrocytosis. In contrast, EPOR was dramatically upregulated within 24 h after hypoxia-ischemia. These results suggest that there is a rapid response of EPOR to the hypoxic-ischemic stimulus, which seems to precede that of EPO, leading to the hypothesis that the EPO/EPOR system is implicated in the processes of neuroprotection from hypoxia-ischemia.

Topics: Animals; Animals, Newborn; Blotting, Western; Carotid Arteries; Erythropoietin; Gene Expression Regulation; Gliosis; Hypoxia-Ischemia, Brain; Immunohistochemistry; Ligation; Rats; Receptors, Erythropoietin; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Time Factors

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

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

Hypoxic-ischemic encephalopathy seen in survivors of perinatal asphyxia is a frequently encountered and a major clinical problem for which there is currently no effective treatment. Hematopoietic neuroprotective agents, such as erythropoietin (EPO) may rescue neurons from cell death in this setting. EPO is a cytokine hormone that has neuroprotective effect in vitro and in vivo. In this study, we evaluated the effect of posthypoxic EPO administration in an animal model of neonatal hypoxic-ischemic injury. Our results show that a single intracerebroventricular injection of EPO immediately after hypoxic-ischemic insult in neonatal rat model of hypoxic-ischemia reduced the extent of hypoxic-ischemic brain damage. The mean infarct volume assessed 7 days after hypoxia was significantly smaller in EPO-treated group than in the control group. These findings suggest that EPO may provide benefit after hypoxic-ischemic events in the developing brain, a major contributor to static encephalopathy and cerebral palsy.

Topics: Animals; Animals, Newborn; Brain Injuries; Disease Models, Animal; Erythropoietin; Hypoxia-Ischemia, Brain; Injections, Intraventricular; Neuroprotective Agents; Rats; Rats, Wistar

The effect of systemic erythropoietin pretreatment on hypoxic ischemic injury was examined in neonatal mice. Injury was significantly less in cortex, hippocampus, striatum and thalamus of erythropoietin-treated animals (5 U/g vs vehicle) 24 h after hypoxic ischemia and in all of these regions except hippocampus at 7 days. Activated caspase-3- and activated NFkappaB-immunoreactive neurons were observed in the injured areas; these areas were smaller in the erythropoietin group. To our knowledge, this is the first report demonstrating persistent neuroprotective effects of erythropoietin in neonatal mice.

Topics: Animals; Brain; Caspase 3; Caspases; Cerebral Cortex; Corpus Striatum; Erythropoietin; Hippocampus; Hypoxia-Ischemia, Brain; Immunohistochemistry; Mice; Mice, Inbred Strains; Neuroprotective Agents; NF-kappa B; Thalamus; Time Factors

Recent studies have shown that erythropoietin protects neurons from glutamate toxicity and ischemia. This study was performed to evaluate the potential neuroprotective effect of erythropoietin during experimental hypothermic circulatory arrest.. Twenty pigs were randomized to receive intravenously either 500 IU/kg recombinant human erythropoietin or saline before a 75-minute period of hypothermic circulatory arrest at an intracerebral temperature of 18 degrees C.. After the administration of erythropoietin, its concentration in the cerebrospinal fluid increased 4.5-fold 8 hours after the start of rewarming, whereas it did not increase in control animals. The 7-day survival rate was 60% in the erythropoietin group and 70% in the control group (P = 1.0). No significant differences were observed between the study groups in terms of electroencephalography, behavioral score, and histopathologic score. The erythropoietin group had higher vascular resistance and mean arterial pressure values, lower intracerebral concentrations of glutamate and glycerol, higher brain tissue oxygen tension, and lower apoptotic index.. Administration of 500 IU/kg erythropoietin intravenously before hypothermic circulatory arrest was followed by an increased erythropoietin concentration in the cerebrospinal fluid. Although previous studies have demonstrated neuroprotective effects of erythropoietin during brain ischemia, the present study, using a chronic porcine model, failed to show any significant benefit after administration of erythropoietin in terms of mortality or brain histopathology. Lower intracerebral concentrations of glutamate and glycerol, higher brain tissue oxygen tension, and lower apoptotic index observed in the erythropoietin group, however, suggest that a distinct neuroprotective effect of erythropoietin might be achieved at different dosages and timing of administration.

Topics: Animals; Apoptosis; Brain; Electroencephalography; Erythropoietin; Female; Glutamic Acid; Heart Arrest, Induced; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Neuroprotective Agents; Survival Rate; Swine

In an in vitro model of cerebral ischemia (oxygen glucose deprivation, OGD) we investigated whether erythropoietin (EPO) plays a critical role in ischemic preconditioning. We found that EPO time and dose-dependently induced protection against OGD in rat primary cortical neurons. Protection was significant at 5 min and reached a maximum at 48 hr after EPO application. Protection was blocked by the coapplication of a soluble Epo receptor (sEpoR) or an antibody against EpoR (anti-EpoR). Medium transfer from OGD-treated astrocytes to untreated neurons induced protection against OGD in neurons, which was attenuated strongly by the application of sEpoR and anti-EpoR. In contrast, medium transfer from OGD-treated neurons to untreated neurons induced protection against OGD that did not involve EPO. In astrocytes the OGD enhanced the nuclear translocation of hypoxia-inducible factor 1 (HIF-1), the major transcription factor regulating EPO expression. Consequently, transcription of EPO-mRNA was increased in astrocytes after OGD. Cultured neurons express EpoR, and the Janus kinase-2 (JAK-2) inhibitor AG490 abolished EPO-induced tolerance against OGD. Furthermore, EPO-induced neuroprotection as well as phosphorylation of the proapoptotic Bcl family member Bad was reduced by the phosphoinositide-3 kinase (PI3K) inhibitor LY294002. The results suggest that astrocytes challenged with OGD provide paracrine protective signals to neurons. We provide evidence for the following signaling cascade: HIF-1 is activated rapidly by hypoxia in astrocytes. After HIF-1 activation the astrocytes express and release EPO. EPO activates the neuronal EPO receptor and, subsequently, JAK-2 and thereby PI3K. PI3K deactivates BAD via Akt-mediated phosphorylation and thus may inhibit hypoxia-induced apoptosis in neurons. Our results establish EPO as an important paracrine neuroprotective mediator of ischemic preconditioning.

Topics: Animals; Antibodies; Apoptosis; Astrocytes; bcl-Associated Death Protein; Brain; Carrier Proteins; Cells, Cultured; DNA-Binding Proteins; Dose-Response Relationship, Drug; Erythropoietin; Glucose; Hypoxia-Inducible Factor 1; Hypoxia-Inducible Factor 1, alpha Subunit; Hypoxia-Ischemia, Brain; Ischemic Preconditioning; Janus Kinase 2; Models, Biological; Neurons; Nuclear Proteins; Paracrine Communication; Phosphatidylinositol 3-Kinases; Phosphorylation; Protein-Tyrosine Kinases; Proto-Oncogene Proteins; Rats; Rats, Wistar; Receptors, Erythropoietin; RNA, Messenger; Signal Transduction; Transcription Factors

Using immunohistochemistry, expression of erythropoietin (EPO), a hypoxia-inducible neuroprotective factor, and its receptor (EPOR) were investigated in human brain tissue after ischemia/hypoxia. Autopsy brains of neuropathologically normal subjects were compared to those with ischemic infarcts or hypoxic damage. In normal brain, weak EPO/EPOR immunoreactivity was mainly neuronal. In fresh infarcts, EPO immunoreactivity appeared in vascular endothelium, EPOR in microvessels and neuronal fibers. In older infarcts reactive astrocytes exhibited EPO/EPOR immunoreactivity. Acute hypoxic brain damage was associated with vascular EPO expression, older hypoxic damage with EPO/EPOR immunoreactivity in reactive astrocytes. The pronounced up-regulation of EPO/EPOR in human ischemic/hypoxic brains underlines their role as an endogenous neuroprotective system and suggests a novel therapeutic potential in cerebrovascular disease for EPO, a clinically well-characterized and safe compound.

Topics: Adult; Aged; Astrocytes; Brain; Encephalitis; Endothelium, Vascular; Erythropoietin; Female; Fluorescent Antibody Technique; Glial Fibrillary Acidic Protein; Humans; Hypoxia-Ischemia, Brain; Male; Middle Aged; Nerve Degeneration; Neurofilament Proteins; Neurons; Receptors, Erythropoietin; von Willebrand Factor