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He D, Shi X, Liang L, Zhao Y, Ma S, Cao S, Liu B, Gao Z, Zhang X, Fan Z, Kuang F, Zhang H. Microglial EPOR Contribute to Sevoflurane-induced Developmental Fine Motor Deficits Through Synaptic Pruning in Mice. Neurosci Bull 2024:10.1007/s12264-024-01248-5. [PMID: 38907076 DOI: 10.1007/s12264-024-01248-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 02/17/2024] [Indexed: 06/23/2024] Open
Abstract
Clinical researches including the Mayo Anesthesia Safety in Kids (MASK) study have found that children undergoing multiple anesthesia may have a higher risk of fine motor control difficulties. However, the underlying mechanisms remain elusive. Here, we report that erythropoietin receptor (EPOR), a microglial receptor associated with phagocytic activity, was significantly downregulated in the medial prefrontal cortex of young mice after multiple sevoflurane anesthesia exposure. Importantly, we found that the inhibited erythropoietin (EPO)/EPOR signaling axis led to microglial polarization, excessive excitatory synaptic pruning, and abnormal fine motor control skills in mice with multiple anesthesia exposure, and those above-mentioned situations were fully reversed by supplementing EPO-derived peptide ARA290 by intraperitoneal injection. Together, the microglial EPOR was identified as a key mediator regulating early synaptic development in this study, which impacted sevoflurane-induced fine motor dysfunction. Moreover, ARA290 might serve as a new treatment against neurotoxicity induced by general anesthesia in clinical practice by targeting the EPO/EPOR signaling pathway.
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Affiliation(s)
- Danyi He
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China
| | - Xiaotong Shi
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China
| | - Lirong Liang
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China
| | - Youyi Zhao
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China
| | - Sanxing Ma
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China
| | - Shuhui Cao
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China
| | - Bing Liu
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China
| | - Zhenzhen Gao
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China
| | - Xiao Zhang
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China
| | - Ze Fan
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China.
- Department of Neurobiology and Institute of Neurosciences, School of Basic Medicine, Fourth Military Medical University, Xi'an, 710032, China.
| | - Fang Kuang
- Department of Neurobiology and Institute of Neurosciences, School of Basic Medicine, Fourth Military Medical University, Xi'an, 710032, China.
| | - Hui Zhang
- State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, China.
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Zawadzka M, Kwaśniewska A, Miazga K, Sławińska U. Perspectives in the Cell-Based Therapies of Various Aspects of the Spinal Cord Injury-Associated Pathologies: Lessons from the Animal Models. Cells 2021; 10:cells10112995. [PMID: 34831217 PMCID: PMC8616284 DOI: 10.3390/cells10112995] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 10/25/2021] [Accepted: 10/31/2021] [Indexed: 02/07/2023] Open
Abstract
Traumatic injury of the spinal cord (SCI) is a devastating neurological condition often leading to severe dysfunctions, therefore an improvement in clinical treatment for SCI patients is urgently needed. The potential benefits of transplantation of various cell types into the injured spinal cord have been intensively investigated in preclinical SCI models and clinical trials. Despite the many challenges that are still ahead, cell transplantation alone or in combination with other factors, such as artificial matrices, seems to be the most promising perspective. Here, we reviewed recent advances in cell-based experimental strategies supporting or restoring the function of the injured spinal cord with a particular focus on the regenerative mechanisms that could define their clinical translation.
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The effects of normoxic endurance exercise on erythropoietin (EPO) production and the impact of selective β 1 and non-selective β 1 + β 2 adrenergic receptor blockade. Eur J Appl Physiol 2021; 121:1499-1511. [PMID: 33646423 DOI: 10.1007/s00421-020-04558-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 11/09/2020] [Indexed: 10/22/2022]
Abstract
PURPOSE Habitual endurance exercise results in increased erythropoiesis, which is primarily controlled by erythropoietin (EPO), yet studies demonstrating upregulation of EPO via a single bout of endurance exercise have been equivocal. This study compares the acute EPO response to 30 min of high versus 90 min of moderate-intensity endurance exercise and whether that response can be upregulated via selective adrenergic receptor blockade. METHODS Using a counterbalanced, cross-over design, fifteen participants (age 28 ± 8) completed two bouts of running (30-min, high intensity vs 90-min, moderate intensity) matched for overall training stress. A separate cohort of fourteen participants (age 31 ± 6) completed three bouts of 30-min high-intensity cycling after ingesting the preferential β1-adrenergic receptor (AR) antagonist bisoprolol, the non-preferential β1 + β2 antagonist nadolol or placebo. Venous blood was collected before, during, and after exercise, and serum EPO levels were determined by ELISA. RESULTS No detectable EPO response was observed during or after high intensity running, however, in the moderate-intensity trial EPO was significantly elevated at both during-exercise timepoints (+ 6.8% ± 2.3% at 15 min and + 8.7% ± 2.2% at 60 min). No significant change in EPO was observed post-cycling or between the trials involving βAR blockade. CONCLUSION Neither training mode (running or cycling), nor beta-blockade significantly influenced the EPO response to 30 min of high-intensity exercise, however, 90 min of moderate-intensity running elevated EPO during exercise, returning to baseline immediately post-exercise. Identifying the optimal mode, duration and intensity required to evoke an EPO response to exercise may help tailor exercise prescriptions designed to maximize EPO response for both performance and clinical applications.
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Kolesnichenko PD, Scheblykina OV, Nesterova NI, Scheblykin DV, Nesterov AV, Pokrovskiy MV, Zhuchenko MA, Tverskoy AV, Reznikov KM. ADDITIVE NEUROPROTECTIVE EFFECT OF 3-HYDROXYPYRIDINE DERIVATIVES AND HUMAN ERYTHROPOETIN ANALOGUE ON A HEMORRHAGIC STROKE MODEL IN RATS. PHARMACY & PHARMACOLOGY 2020. [DOI: 10.19163/2307-9266-2020-8-3-169-180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The correction of free radical oxidation processes is one of the most promising strategies of neuroprotection in acute cerebrovascular disorders.The aim of the study is an experimental study of the neuroprotective effects of 3-hydroxypyridine and erythropoietin derivatives, as well as their combined use.Materials and methods. The study was performed on 109 male Wistar rats. The neuroprotective effect of the substances was studied on a hemorrhagic stroke model. The study drugs were administered to the animals intraperitoneally. Carbamylated darbepoetin was administered three times in advance at the dose of 100 µg/kg within intervals of 3 days, the last injection took place 1 hour before the operation (the total dose was 300 mg/kg). Etoxidol was administered once 1 hour before the surgery at the dose of 50 mg/kg. The survival rate, behavioral features and the state of the animals on the 1st, 3rd, 7th and 14th days were recorded, and the morphological assessment of the brain was carried out.Results. The investigated substances had a positive effect on both the survival rate of the animals during the first day and on the 14th day. The best survival rates on the 14th day were recorded in the group of a combined use of ethoxydol and carbamylated darbepoetin (75%). Thus, in this group of rats, a faster recovery of neurological disorders was already distinguished from the first day on. By the 7th day, more than 50% of the rats receiving the combination of the studied drugs, had had a slight neurological deficit (up to 3 points on the McGrow scale); by the 14th day there had been only minor changes in the neurological status in the rats of this group. A pronounced neuroprotective effect of the combination of 3-hydroxypyridine and erythropoietin derivatives has been confirmed by a histological examination of brain slices – a more rapid decrease in the size of perifocal edema and microcirculation disorders, less damage to neurons and glial elements, and faster processes of resorption and organization of hemorrhage. A macroscopic examination of the brain sections stained with triphenyltetrazolium chloride of the dying rats, showed that perifocal necrosis had been the main cause of high mortality in the control group after the 3rd day.Conclusion. As a result of the experiment, the nephroprotective effect of the studied derivatives of 3-hydroxypyridine and erythropoietin has been proved. Moreover, the combination of these drugs has shown a greater neuroprotective activity than their isolated use. The additive effect of these drugs was due to their action mechanism resulting from the synergism of various structures and components of the cells.
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Affiliation(s)
| | | | - N. I. Nesterova
- Belgorod State National Research University;
Belgorod Bureau of Forensic Medical Examination
| | | | | | | | | | | | - K. M. Reznikov
- Voronezh State Medical University named after N.N. Burdenko
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Erythropoietin Mediated Bone Loss in Mice Is Dose-Dependent and Mostly Irreversible. Int J Mol Sci 2020; 21:ijms21113817. [PMID: 32471308 PMCID: PMC7312352 DOI: 10.3390/ijms21113817] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/19/2020] [Accepted: 05/24/2020] [Indexed: 01/14/2023] Open
Abstract
Recent studies have demonstrated that erythropoietin (EPO) treatment in mice results in trabecular bone loss. Here, we investigated the dose-response relationship between EPO, hemoglobin (Hgb) and bone loss and examined the reversibility of EPO-induced damage. Increasing doses of EPO over two weeks led to a dose-dependent increase in Hgb in young female mice, accompanied by a disproportionate decrease in trabecular bone mass measured by micro-CT (µCT). Namely, increasing EPO from 24 to 540 IU/week produced a modest 12% rise in Hgb (20.2 ± 1.3 mg/dL vs 22.7 ± 1.3 mg/dL), while trabecular bone volume fraction (BV/TV) in the distal femur decreased dramatically (27 ± 8.5% vs 53 ± 10.2% bone loss). To explore the long-term skeletal effects of EPO, we treated mice for two weeks (540 IU/week) and monitored bone mass changes after treatment cessation. Six weeks post-treatment, there was only a partial recovery of the trabecular microarchitecture in the femur and vertebra. EPO-induced bone loss is therefore dose-dependent and mostly irreversible at doses that offer only a minor advantage in the treatment of anemia. Because patients requiring EPO therapy are often prone to osteoporosis, our data advocate for using the lowest effective EPO dose for the shortest period of time to decrease thromboembolic complications and minimize the adverse skeletal outcome.
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Zheng Q, Ma Y, Chen S, Che Q, Chen D. The Integrated Landscape of Biological Candidate Causal Genes in Coronary Artery Disease. Front Genet 2020; 11:320. [PMID: 32373157 PMCID: PMC7186505 DOI: 10.3389/fgene.2020.00320] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Accepted: 03/18/2020] [Indexed: 12/27/2022] Open
Abstract
Background Genome-wide association studies (GWASs) have identified more than 150 genetic loci that demonstrate robust association with coronary artery disease (CAD). In contrast to the success of GWAS, the translation from statistical signals to biological mechanism and exploration of causal genes for drug development remain difficult, owing to the complexity of gene regulatory and linkage disequilibrium patterns. We aim to prioritize the plausible causal genes for CAD at a genome-wide level. Methods We integrated the latest GWAS summary statistics with other omics data from different layers and utilized eight different computational methods to predict CAD potential causal genes. The prioritized candidate genes were further characterized by pathway enrichment analysis, tissue-specific expression analysis, and pathway crosstalk analysis. Results Our analysis identified 55 high-confidence causal genes for CAD, among which 15 genes (LPL, COL4A2, PLG, CDKN2B, COL4A1, FES, FLT1, FN1, IL6R, LPA, PCSK9, PSRC1, SMAD3, SWAP70, and VAMP8) ranked the highest priority because of consistent evidence from different data-driven approaches. GO analysis showed that these plausible causal genes were enriched in lipid metabolic and extracellular regions. Tissue-specific enrichment analysis revealed that these genes were significantly overexpressed in adipose and liver tissues. Further, KEGG and crosstalk analysis also revealed several key pathways involved in the pathogenesis of CAD. Conclusion Our study delineated the landscape of CAD potential causal genes and highlighted several biological processes involved in CAD pathogenesis. Further studies and experimental validations of these genes may shed light on mechanistic insights into CAD development and provide potential drug targets for future therapeutics.
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Affiliation(s)
- Qiwen Zheng
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
| | - Yujia Ma
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
| | - Si Chen
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
| | - Qianzi Che
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
| | - Dafang Chen
- Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China
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Wu BW, Liu Y, Wu MS, Meng YH, Lu M, Guo JD, Zhou YH. Downregulation of microRNA-135b promotes atherosclerotic plaque stabilization in atherosclerotic mice by upregulating erythropoietin receptor. IUBMB Life 2019; 72:198-213. [PMID: 31444954 DOI: 10.1002/iub.2155] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 08/06/2019] [Indexed: 01/23/2023]
Abstract
Atherosclerotic plaque rupture is an important pathophysiologic mechanism of acute coronary syndrome. Emerging microRNAs (miRNAs) have been implicated in the atherosclerotic plaque formation and macrophage autophagy during the development of atherosclerosis (AS). Hence, this study was conducted to explore the role microRNA-135b (miR-135b) in macrophages and atherosclerotic plaque in mouse models of AS. The expression of miR-135b and erythropoietin receptor (EPOR) was altered in atherosclerotic mice to clarify their effect on inflammation, cell activities of aortic tissues, and macrophage autophagy. The obtained findings unraveled that miR-135b was upregulated and EPOR was downregulated in atherosclerotic mice. Upregulated miR-135b expression promoted cell apoptosis and inflammation, along with inhibited cell proliferation and decreased macrophage autophagy. Notably, miR-135 was validated to target EPOR and activate the PI3K/Akt signaling pathway. Moreover, miR-135b inhibition attenuated inflammation, atherosclerotic plaque development, and promoted macrophage autophagy. Besides, the effect of miR-135b inhibition was reversed in response to EPOR silencing. Taken conjointly, the study revealed that inhibition of miR-135b promoted macrophage autophagy and atherosclerotic plaque stabilization in atherosclerotic mice by inactivating the PI3K/Akt signaling pathway and upregulating EPOR.
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Affiliation(s)
- Bo-Wen Wu
- Department of Biochemistry, Basic Medicine College, Hebei University of Chinese Medicine, Shijiazhuang, Hebei Province, People's Republic of China.,Hebei Key Laboratory of Chinese Medicine Research on Cardio-Cerebrovascular Disease, Shijiazhuang, Hebei Province, People's Republic of China
| | - Yu Liu
- Department of Biochemistry, Basic Medicine College, Hebei University of Chinese Medicine, Shijiazhuang, Hebei Province, People's Republic of China.,Hebei Key Laboratory of Chinese Medicine Research on Cardio-Cerebrovascular Disease, Shijiazhuang, Hebei Province, People's Republic of China
| | - Mi-Shan Wu
- Hebei Key Laboratory of Chinese Medicine Research on Cardio-Cerebrovascular Disease, Shijiazhuang, Hebei Province, People's Republic of China.,Department of Formulaology, Basic Medicine College, Hebei University of Chinese Medicine, Shijiazhuang, Hebei Province, People's Republic of China
| | - Yun-Hui Meng
- Hebei Key Laboratory of Chinese Medicine Research on Cardio-Cerebrovascular Disease, Shijiazhuang, Hebei Province, People's Republic of China.,Department of Formulaology, Basic Medicine College, Hebei University of Chinese Medicine, Shijiazhuang, Hebei Province, People's Republic of China
| | - Meng Lu
- Hebei Key Laboratory of Chinese Medicine Research on Cardio-Cerebrovascular Disease, Shijiazhuang, Hebei Province, People's Republic of China.,Department of Formulaology, Basic Medicine College, Hebei University of Chinese Medicine, Shijiazhuang, Hebei Province, People's Republic of China
| | - Jin-Dong Guo
- Hebei Key Laboratory of Chinese Medicine Research on Cardio-Cerebrovascular Disease, Shijiazhuang, Hebei Province, People's Republic of China.,Department of Formulaology, Basic Medicine College, Hebei University of Chinese Medicine, Shijiazhuang, Hebei Province, People's Republic of China
| | - Yu-Hui Zhou
- Hebei Key Laboratory of Chinese Medicine Research on Cardio-Cerebrovascular Disease, Shijiazhuang, Hebei Province, People's Republic of China.,Department of Formulaology, Basic Medicine College, Hebei University of Chinese Medicine, Shijiazhuang, Hebei Province, People's Republic of China
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Cohrs G, Goerden S, Lucius R, Synowitz M, Mehdorn HM, Held-Feindt J, Knerlich-Lukoschus F. Spatial and Cellular Expression Patterns of Erythropoietin-Receptor and Erythropoietin during a 42-Day Post-Lesional Time Course after Graded Thoracic Spinal Cord Impact Lesions in the Rat. J Neurotrauma 2018; 35:593-607. [PMID: 28895456 DOI: 10.1089/neu.2017.4981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Erythropoietin (Epo) exhibits promising neuroregenerative potential for spinal cord injury (SCI), and might be involved in other long-term sequelae, such as neuropathic pain development. The current studies investigated the time courses and spatial and cellular patterns of Epo and erythropoietin receptor (EpoR) expression along the spinal axis after graded SCI. Male Long Evans rats received 100 kdyn, 150 kdyn, and 200 kdyn thoracic (T9) contusions from an Infinite Horizon impactor. Sham controls received laminectomies. Anatomical and quantitative immunohistochemical analyses of the EpoR/Epo expression along the whole spinal axis were performed 7, 15, and 42 postoperative days (DPO) after the lesioning. Cellular expression was investigated by double- and triple-labeling for EpoR/Epo with cellular markers and proliferating cells in subgroups of 5-bromo-2-deoxyuridine pre-treated animals. Prolonged EpoR/Epo-expression was confirmed by real-time reverse transcriptase polymerase chain reaction (RT-PCR). Quantified EpoR/Epo immunoreactivities in pain-related spinal cord regions and ventrolateral white matter (VLWM) were correlated with the mechanical sensitivity thresholds and locomotor function of the respective animals. EpoR and Epo were constitutively expressed in the ventral horn neurons and vascular and glial cells in the dorsal columns (DC) and the VLWM. After SCI, in addition to expression in the lesion core, EpoR/Epo immunoreactivities exhibited significant time- and lesion grade-dependent induction in the DC and VLWM along the spinal axis. EpoR and Epo immunoreactive cells were co-stained with markers for astroglial, neural precursor cell and vascular markers. In the VLWM, EpoR- and Epo-positive proliferating cells were co-stained with glial fibrillary acidic protein (GFAP) and nestin. The DC EpoR/Epo immunoreactivities exhibited linear relationships with the behavioral correlates of post-lesional chronic pain development at DPO 42. SCI leads to long-lasting multicellular EpoR/Epo induction beyond the lesion core in the spinal cord regions that are involved in central pain development and regenerative processes. Our studies provide a time frame to investigate the effects of Epo application on motor function or pain development, especially in the later time course after lesioning.
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Affiliation(s)
- Gesa Cohrs
- 1 Department of Neurosurgery, University Hospital of Schleswig-Holstein Campus Kiel , Kiel, Germany
| | - Stephan Goerden
- 1 Department of Neurosurgery, University Hospital of Schleswig-Holstein Campus Kiel , Kiel, Germany
| | - Ralph Lucius
- 2 Anatomical Institute, Christian-Albrechts University Kiel , Kiel, Germany
| | - Michael Synowitz
- 1 Department of Neurosurgery, University Hospital of Schleswig-Holstein Campus Kiel , Kiel, Germany
| | | | - Janka Held-Feindt
- 1 Department of Neurosurgery, University Hospital of Schleswig-Holstein Campus Kiel , Kiel, Germany
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Moransard M, Bednar M, Frei K, Gassmann M, Ogunshola OO. Erythropoietin reduces experimental autoimmune encephalomyelitis severity via neuroprotective mechanisms. J Neuroinflammation 2017; 14:202. [PMID: 29029628 PMCID: PMC5640948 DOI: 10.1186/s12974-017-0976-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 10/03/2017] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Treatment with erythropoietin (Epo) in experimental autoimmune encephalomyelitis (EAE), the rodent model of multiple sclerosis (MS), has consistently been shown to ameliorate disease progression and improve overall outcome. The effect has been attributed to modulation of the immune response and/or preservation of the central nervous system (CNS) tissue integrity. It remains unclear, however, if (a) Epo acts primarily in the CNS or the periphery and if (b) Epo's beneficial effect in EAE is mainly due to maintaining CNS tissue integrity or to modulation of the immune response. If Epo acts primarily by modulating the immune system, where is this modulation required? In the periphery, the CNS or both? METHODS To address these questions, we used two well-characterized transgenic mouse strains that constitutively overexpress recombinant human Epo (rhEpo) either systemically (tg6) or in CNS only (tg21) in a MOG-induced EAE model. We assessed clinical severity, disease progression, immunomodulation, and CNS tissue integrity, including neuronal survival. RESULTS Although disease onset remained unaffected, EAE progression was alleviated in transgenic animals compared to controls with both lines performing equally well showing that expression of Epo in the periphery is not required; Epo expression in the CNS is sufficient. Immunomodulation was observed in both strains but surprisingly the profile of modulation differed substantially between strains. Modulation in the tg21 strain was limited to a reduction in macrophages in the CNS, with no peripheral immunomodulatory effects observed. In contrast, in the tg6 strain, macrophages were upregulated in the CNS, and, in the periphery of this strain, T cells and macrophages were downregulated. The lack of a consistent immunomodulatory profile across both transgenic species suggests that immunomodulation by Epo is unlikely to be the primary mechanism driving amelioration of EAE. Finally, CNS tissue integrity was affected in all strains. Although myelin appeared equally damaged in all strains, neuronal survival was significantly improved in the spinal cord of tg21 mice, indicating that Epo may ameliorate EAE predominantly by protecting neurons. CONCLUSIONS Our data suggests that moderate elevated brain Epo levels provide clinically significant neuroprotection in EAE without modulation of the immune response making a significant contribution.
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Affiliation(s)
- M Moransard
- Department of Internal Medicine, Section of Clinical Immunology, University Hospital Zürich, Zurich, Switzerland
| | - M Bednar
- Institute of Veterinary Physiology and Zurich Center of Integrative Human Physiology (ZIHP), Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057, Zurich, Switzerland
| | - K Frei
- Department of Neurosurgery, University Hospital Zurich, CH-8006, Zurich, Switzerland
| | - M Gassmann
- Institute of Veterinary Physiology and Zurich Center of Integrative Human Physiology (ZIHP), Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057, Zurich, Switzerland
- Universidad Peruana Cayetano Heredia (UPCH), Lima, Peru
| | - O O Ogunshola
- Institute of Veterinary Physiology and Zurich Center of Integrative Human Physiology (ZIHP), Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057, Zurich, Switzerland.
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Electroacupuncture at GV20 and ST36 Exerts Neuroprotective Effects via the EPO-Mediated JAK2/STAT3 Pathway in Cerebral Ischemic Rats. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2017; 2017:6027421. [PMID: 28848617 PMCID: PMC5564076 DOI: 10.1155/2017/6027421] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 06/02/2017] [Accepted: 07/03/2017] [Indexed: 11/17/2022]
Abstract
Background While electroacupuncture (EA) in cerebral ischemia has been used to promote functional recovery, the underlying mechanism of its protective effect remains poorly understood. Objective We investigated the effects of EA stimulation at GV20 and ST36 to observe the changes in erythropoietin- (EPO-) mediated Janus family tyrosine kinases 2 (JAK2) signal transducers and activators of the transcription 3 (STAT3) cell pathway. Methods Thirty-six specific pathogen-free Sprague-Dawley (SD) male rats were randomly assigned to three groups: the sham-operated group (S group), the middle cerebral artery occlusion (MCAO) group (M group), and the EA group. Neurological deficits were assessed through the Ludmila Belayev 12-score test and 2,3,5-triphenyltetrazolium chloride (TTC) staining was shown. The protein and mRNA expression levels of EPO, the EPO receptor (EpoR), p-JAK2, JAK2, p-STAT3, and STAT3 were examined to explore the EA effect on rats with cerebral ischemic reperfusion injury (CIRI). Results EA significantly decreased infarct size and improved neurological function. Furthermore, target EPO, EpoR, JAK2, and STAT3 mRNA and protein levels significantly increased in the EA group. Conclusions EA exerts a neuroprotective effect, possibly via the regulation of the EPO-mediated JAK2/STAT3 cell pathway and downstream apoptotic pathways in a rat CIRI model.
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Steppich B, Groha P, Ibrahim T, Schunkert H, Laugwitz KL, Hadamitzky M, Kastrati A, Ott I. Effect of Erythropoietin in patients with acute myocardial infarction: five-year results of the REVIVAL-3 trial. BMC Cardiovasc Disord 2017; 17:38. [PMID: 28109258 PMCID: PMC5251242 DOI: 10.1186/s12872-016-0464-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Accepted: 12/29/2016] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Erythropoietin (EPO) has been suggested to promote cardiac repair after MI. However, the randomized, double-blind, placebo controlled REVIVAL-3 trial showed that short term high dose EPO in timely reperfused myocardium does not improve left ventricular ejection fraction after 6 months. Moreover, the study raised safety concerns due to a trend towards a higher incidence of adverse clinical events as well as a increase in neointima formation after treatment with EPO. The present study therefore aimed to assess the 5-year clinical outcomes. METHODS After successful reperfusion 138 patients with STEMI were randomly assigned to receive epoetin beta (3.33×104 U, n = 68) or placebo (n = 70) immediately, 24 and 48 h after percutaneous coronary intervention. The primary outcome of the present study- the combined incidence of MACE 5 years after randomization - occurred in 25% of the patients assigned to epoetin beta and 17% of the patients assigned to placebo (RR 1.5; 95% CI 0.8-3.5; p = 0.26). Target lesion revascularization was required in 15 patients (22.1%) treated with epoetin-ß and 9 patients (12.9%) treated with placebo (p = 0.15). Analysis of patients in the upper and lower quartile of baseline hemoglobin as an indirect estimate of endogenous erythropoietin levels revealed no significant impact of endogenous erythropoietin on efficiency of exogen administered epoetin-ß in terms of death and MACE. CONCLUSION These long-term follow-up data show that epoetin beta does not improve clinical outcomes of patients with acute myocardial infarction. TRIAL REGISTRATION URL www.clinicaltrials.gov ; Unique identifier NCT00390832; trial registration date October 19th 2006.
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Affiliation(s)
- Birgit Steppich
- Deutsches Herzzentrum der Technischen Universität München, Lazarettstr. 36, 80636, Munich, Germany.
| | - Philip Groha
- Deutsches Herzzentrum der Technischen Universität München, Lazarettstr. 36, 80636, Munich, Germany
| | - Tareq Ibrahim
- Medizinische Klinik Klinikum rechts der Isar der Technischen Universität München, Ismaningerstr. 22, 81675, Munich, Germany
| | - Heribert Schunkert
- Medizinische Klinik Klinikum rechts der Isar der Technischen Universität München, Ismaningerstr. 22, 81675, Munich, Germany
| | - Karl-Ludwig Laugwitz
- Medizinische Klinik Klinikum rechts der Isar der Technischen Universität München, Ismaningerstr. 22, 81675, Munich, Germany
| | - Martin Hadamitzky
- Deutsches Herzzentrum der Technischen Universität München, Lazarettstr. 36, 80636, Munich, Germany
| | - Adnan Kastrati
- Deutsches Herzzentrum der Technischen Universität München, Lazarettstr. 36, 80636, Munich, Germany
| | - Ilka Ott
- Deutsches Herzzentrum der Technischen Universität München, Lazarettstr. 36, 80636, Munich, Germany
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Heikal L, Ghezzi P, Mengozzi M, Stelmaszczuk B, Feelisch M, Ferns GA. Erythropoietin and a nonerythropoietic peptide analog promote aortic endothelial cell repair under hypoxic conditions: role of nitric oxide. HYPOXIA 2016; 4:121-133. [PMID: 27800514 PMCID: PMC5085277 DOI: 10.2147/hp.s104377] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The cytoprotective effects of erythropoietin (EPO) and an EPO-related nonerythropoietic analog, pyroglutamate helix B surface peptide (pHBSP), were investigated in an in vitro model of bovine aortic endothelial cell injury under normoxic (21% O2) and hypoxic (1% O2) conditions. The potential molecular mechanisms of these effects were also explored. Using a model of endothelial injury (the scratch assay), we found that, under hypoxic conditions, EPO and pHBSP enhanced scratch closure by promoting cell migration and proliferation, but did not show any effect under normoxic conditions. Furthermore, EPO protected bovine aortic endothelial cells from staurosporine-induced apoptosis under hypoxic conditions. The priming effect of hypoxia was associated with stabilization of hypoxia inducible factor-1α, EPO receptor upregulation, and decreased Ser-1177 phosphorylation of endothelial nitric oxide synthase (NOS); the effect of hypoxia on the latter was rescued by EPO. Hypoxia was associated with a reduction in nitric oxide (NO) production as assessed by its oxidation products, nitrite and nitrate, consistent with the oxygen requirement for endogenous production of NO by endothelial NOS. However, while EPO did not affect NO formation in normoxia, it markedly increased NO production, in a manner sensitive to NOS inhibition, under hypoxic conditions. These data are consistent with the notion that the tissue-protective actions of EPO-related cytokines in pathophysiological settings associated with poor oxygenation are mediated by NO. These findings may be particularly relevant to atherogenesis and postangioplasty restenosis.
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Affiliation(s)
- Lamia Heikal
- Brighton and Sussex Medical School, Falmer, Brighton
| | - Pietro Ghezzi
- Brighton and Sussex Medical School, Falmer, Brighton
| | | | - Blanka Stelmaszczuk
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital and Institute for Life Sciences, Southampton, UK
| | - Martin Feelisch
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital and Institute for Life Sciences, Southampton, UK
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13
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Carbamylated erythropoietin enhances mice ventilatory responses to changes in O2 but not CO2 levels. Respir Physiol Neurobiol 2016; 232:1-12. [PMID: 27317882 DOI: 10.1016/j.resp.2016.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 06/14/2016] [Accepted: 06/15/2016] [Indexed: 11/21/2022]
Abstract
Erythropoietin (EPO) has beneficial tissue-protective effects in several diseases but erythrocytosis may cause deleterious effects in EPO-treated patients. Thus carbamylated-EPO (C-EPO) and other derivatives retaining tissue-protective but lacking bone marrow-stimulating actions have been developed. Although EPO modulates ventilatory responses, the effects of C-EPO on ventilation have not been investigated. Here, basal breathing and respiratory chemoreflexes were measured by plethysmography after acute and chronic treatments with recombinant human C-EPO (rhC-EPO; 15,000 IU/kg during 5days) or saline (control group). Hematocrit, plasma and brainstem rhC-EPO levels were also quantified. Chronic rhC-EPO significantly elevated tissue rhC-EPO levels but not hematocrit. None of the drug regimen altered basal ventilation (normoxia). Chronic but not acute rhC-EPO enhanced hyperoxic ventilatory depression, and sustained the hypoxic ventilatory response mainly via a reduction of the roll-off phase. By contrast, rhC-EPO did not blunt the ventilatory response to hypercapnia. Thus, chronic C-EPO may be a promising therapy to improve breathing during hypoxia while minimizing adverse effects on cardiovascular function.
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14
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Niu HS, Chang CH, Niu CS, Cheng JT, Lee KS. Erythropoietin ameliorates hyperglycemia in type 1-like diabetic rats. DRUG DESIGN DEVELOPMENT AND THERAPY 2016; 10:1877-84. [PMID: 27350742 PMCID: PMC4902144 DOI: 10.2147/dddt.s105867] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Background Erythropoietin (EPO) is widely used in diabetic patients receiving hemodialysis. The role of EPO in glucose homeostasis remains unclear. Therefore, we investigated the effect of EPO on hyperglycemia in rats with type 1-like diabetes. Methods Rats with streptozotocin-induced type 1-like diabetes (STZ rats) were used to estimate the blood glucose-lowering effects of EPO, and changes in the expression levels of glucose transporter 4 (GLUT4) and the hepatic enzyme phosphoenolpyruvate carboxykinase (PEPCK) were identified by Western blot analysis. Results EPO attenuated the hyperglycemia in the STZ rats in a dose-dependent manner without altering the hematopoietic parameters, including the hematocrit and number of red blood cells. The involvement of the EPO receptor (EPOR) was identified using EPOR-specific antibodies. In addition, injection of EPO enhanced the glucose utilization, which was assessed using an intravenous glucose tolerance test in rats. However, blood insulin was not changed by EPO in this assay, showing the insulinotropic action of EPO. Moreover, EPO treatment increased the insulin sensitivity. Western blots indicated that the phosphorylation of AMP-activated protein kinase was enhanced by EPO to support the signaling caused by EPOR activation. Furthermore, the decrease in the GLUT4 level in skeletal muscle was reversed by EPO, and the increase in the PEPCK expression in liver was reduced by EPO, as shown in STZ rats. Conclusion Taken together, the results show that EPO injection may reduce hyperglycemia in diabetic rats through activation of EPO receptors. Therefore, EPO is useful for managing diabetic disorders, particularly hyperglycemia-associated changes. In addition, EPO receptor will be a good target for the development of antihyperglycemic agent(s) in the future.
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Affiliation(s)
- Ho-Shan Niu
- Department of Nursing, Tzu Chi University of Science and Technology, Hualien City, Taiwan, Republic of China
| | - Chin-Hong Chang
- Department of Neurosurgery, Chi-Mei Medical Center, Yong Kang, Tainan City, Taiwan, Republic of China; Department of Medical Research, Chi-Mei Medical Center, Yong Kang, Tainan City, Taiwan, Republic of China
| | - Chiang-Shan Niu
- Department of Nursing, Tzu Chi University of Science and Technology, Hualien City, Taiwan, Republic of China
| | - Juei-Tang Cheng
- Department of Medical Research, Chi-Mei Medical Center, Yong Kang, Tainan City, Taiwan, Republic of China; Institute of Medical Sciences, Chang Jung Christian University, Gueiren, Tainan City, Taiwan, Republic of China
| | - Kung-Shing Lee
- Department of Surgery, Division of Neurosurgery, Pingtung Hospital, Pingtung, Taiwan, Republic of China; Department of Surgery, Kaohsiung Medical University Chung-Ho Memorial Hospital, Kaohsiung City, Taiwan, Republic of China; School of Medicine, Kaohsiung Medical University, Kaohsiung City, Taiwan, Republic of China
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15
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Antioxidant Effect of Erythropoietin during Experimental Chronic Renal Failure. Bull Exp Biol Med 2015; 160:202-4. [DOI: 10.1007/s10517-015-3128-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Indexed: 11/28/2022]
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16
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Hassell KJ, Ezzati M, Alonso-Alconada D, Hausenloy DJ, Robertson NJ. New horizons for newborn brain protection: enhancing endogenous neuroprotection. Arch Dis Child Fetal Neonatal Ed 2015; 100:F541-52. [PMID: 26063194 PMCID: PMC4680177 DOI: 10.1136/archdischild-2014-306284] [Citation(s) in RCA: 135] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 01/28/2015] [Indexed: 01/09/2023]
Abstract
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.
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Affiliation(s)
- K Jane Hassell
- Institute for Women's Health, University College London, London, UK
| | - Mojgan Ezzati
- Institute for Women's Health, University College London, London, UK
| | | | - Derek J Hausenloy
- The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, NIHR University College London Hospitals Biomedical Research Centre, University College London Hospital & Medical School, London, UK
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Heikal L, Ghezzi P, Mengozzi M, Ferns G. Low Oxygen Tension Primes Aortic Endothelial Cells to the Reparative Effect of Tissue-Protective Cytokines. Mol Med 2015; 21:709-716. [PMID: 26349058 DOI: 10.2119/molmed.2015.00162] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 09/01/2015] [Indexed: 12/11/2022] Open
Abstract
Erythropoietin (EPO) has both erythropoietic and tissue-protective properties. The EPO analogues carbamylated EPO (CEPO) and pyroglutamate helix B surface peptide (pHBSP) lack the erythropoietic activity of EPO but retain the tissue-protective properties that are mediated by a heterocomplex of EPO receptor (EPOR) and the β common receptor (βCR). We studied the action of EPO and its analogues in a model of wound healing where a bovine aortic endothelial cells (BAECs) monolayer was scratched and the scratch closure was assessed over 24 h under different oxygen concentrations. We related the effects of EPO and its analogues on repair to their effect on BAECs proliferation and migration (evaluated using a micro-Boyden chamber). EPO, CEPO and pHBSP enhanced scratch closure only at lower oxygen (5%), while their effect at atmospheric oxygen (21%) was not significant. The mRNA expression of EPOR was doubled in 5% compared with 21% oxygen, and this was associated with increased EPOR assessed by immunofluorescence and Western blot. By contrast, βCR mRNA levels were similar in 5% and 21% oxygen. EPO and its analogues increased both BAECs proliferation and migration, suggesting that both may be involved in the reparative process. The priming effect of low oxygen tension on the action of tissue-protective cytokines may be of relevance to vascular disease, including atherogenesis and restenosis.
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Affiliation(s)
- Lamia Heikal
- Brighton and Sussex Medical School, Brighton, United Kingdom
| | - Pietro Ghezzi
- Brighton and Sussex Medical School, Brighton, United Kingdom
| | | | - Gordon Ferns
- Brighton and Sussex Medical School, Brighton, United Kingdom
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Rangarajan V, Juul SE. Erythropoietin: emerging role of erythropoietin in neonatal neuroprotection. Pediatr Neurol 2014; 51:481-8. [PMID: 25266611 PMCID: PMC4180944 DOI: 10.1016/j.pediatrneurol.2014.06.008] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 06/09/2014] [Accepted: 06/12/2014] [Indexed: 01/27/2023]
Abstract
BACKGROUND In the last two decades, there has been considerable evolution in understanding the role of erythropoietin in neuroprotection. Erythropoietin has both paracrine and autocrine functions in the brain. Erythropoietin binding results in neurogenesis, oligodendrogenesis, and angiogenesis. Erythropoietin and its receptor are upregulated by exposure to hypoxia and proinflammatory cytokines after brain injury. While erythropoietin aids in recovery of locally injured neuronal cells, it provides negative feedback to glial cells in the penumbra, thereby limiting extension of injury. This forms the rationale for use of recombinant erythropoietin and erythropoietin mimetics in neonatal and adult injury models of stroke, traumatic brain injury, spinal cord injury, intracerebral hemorrhage, and neonatal hypoxic ischemia. METHOD Review of published literature (Pubmed, Medline, and Google scholar). RESULTS Preclinical neuroprotective data are reviewed, and the rationale for proceeding to clinical trials is discussed. Results from phase I/II trials are presented, as are updates on ongoing and upcoming clinical trials of erythropoietin neuroprotection in neonatal populations. CONCLUSIONS The scientific rationale and preclinical data for erythropoietin neuroprotection are promising. Phase II and III clinical trials are currently in process to determine the safety and efficacy of neuroprotective dosing of erythropoietin for extreme prematurity and hypoxic-ischemic encephalopathy in neonates.
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Affiliation(s)
- Vijayeta Rangarajan
- Division of Neonatology, Department of Pediatrics, University of Washington, Seattle, Washington
| | - Sandra E Juul
- Division of Neonatology, Department of Pediatrics, University of Washington, Seattle, Washington.
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