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Bundgaard A, Gruszczyk AV, Prag HA, Williams C, McIntyre A, Ruhr IM, James AM, Galli GLJ, Murphy MP, Fago A. Low production of mitochondrial reactive oxygen species after anoxia and reoxygenation in turtle hearts. J Exp Biol 2023; 226:jeb245516. [PMID: 37066839 PMCID: PMC10184768 DOI: 10.1242/jeb.245516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 04/03/2023] [Indexed: 04/18/2023]
Abstract
Extremely anoxia-tolerant animals, such as freshwater turtles, survive anoxia and reoxygenation without sustaining tissue damage to their hearts. In contrast, for mammals, the ischemia-reperfusion (IR) injury that leads to tissue damage during a heart attack is initiated by a burst of superoxide (O2·-) production from the mitochondrial respiratory chain upon reperfusion of ischemic tissue. Whether turtles avoid oxidative tissue damage because of an absence of mitochondrial superoxide production upon reoxygenation, or because the turtle heart is particularly protected against this damage, is unclear. Here, we investigated whether there was an increase in mitochondrial O2·- production upon the reoxygenation of anoxic red-eared slider turtle hearts in vivo and in vitro. This was done by measuring the production of H2O2, the dismutation product of O2·-, using the mitochondria-targeted mass-spectrometric probe in vivo MitoB, while in parallel assessing changes in the metabolites driving mitochondrial O2·- production, succinate, ATP and ADP levels during anoxia, and H2O2 consumption and production rates of isolated heart mitochondria. We found that there was no excess production of in vivo H2O2 during 1 h of reoxygenation in turtles after 3 h anoxia at room temperature, suggesting that turtle hearts most likely do not suffer oxidative injury after anoxia because their mitochondria produce no excess O2·- upon reoxygenation. Instead, our data support the conclusion that both the low levels of succinate accumulation and the maintenance of ADP levels in the anoxic turtle heart are key factors in preventing the surge of O2·- production upon reoxygenation.
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Affiliation(s)
- Amanda Bundgaard
- CECAD, University of Cologne, 50931 Cologne, Germany
- Department of Biology, Aarhus University, DK-8000 Aarhus, Denmark
| | - Anja V. Gruszczyk
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | - Hiran A. Prag
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | | | - Angela McIntyre
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | - Ilan M. Ruhr
- Faculty of Medical and Human Sciences, University of Manchester, Manchester M13 9PL, UK
| | - Andrew M. James
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | - Gina L. J. Galli
- Faculty of Medical and Human Sciences, University of Manchester, Manchester M13 9PL, UK
| | - Michael P. Murphy
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | - Angela Fago
- Department of Biology, Aarhus University, DK-8000 Aarhus, Denmark
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Hussan MT, Sakai A, Matsui H. Glutamatergic pathways in the brains of turtles: A comparative perspective among reptiles, birds, and mammals. Front Neuroanat 2022; 16:937504. [PMID: 36059432 PMCID: PMC9428285 DOI: 10.3389/fnana.2022.937504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/22/2022] [Indexed: 11/13/2022] Open
Abstract
Glutamate acts as the main excitatory neurotransmitter in the brain and plays a vital role in physiological and pathological neuronal functions. In mammals, glutamate can cause detrimental excitotoxic effects under anoxic conditions. In contrast, Trachemys scripta, a freshwater turtle, is one of the most anoxia-tolerant animals, being able to survive up to months without oxygen. Therefore, turtles have been investigated to assess the molecular mechanisms of neuroprotective strategies used by them in anoxic conditions, such as maintaining low levels of glutamate, increasing adenosine and GABA, upregulating heat shock proteins, and downregulating KATP channels. These mechanisms of anoxia tolerance of the turtle brain may be applied to finding therapeutics for human glutamatergic neurological disorders such as brain injury or cerebral stroke due to ischemia. Despite the importance of glutamate as a neurotransmitter and of the turtle as an ideal research model, the glutamatergic circuits in the turtle brain remain less described whereas they have been well studied in mammalian and avian brains. In reptiles, particularly in the turtle brain, glutamatergic neurons have been identified by examining the expression of vesicular glutamate transporters (VGLUTs). In certain areas of the brain, some ionotropic glutamate receptors (GluRs) have been immunohistochemically studied, implying that there are glutamatergic target areas. Based on the expression patterns of these glutamate-related molecules and fiber connection data of the turtle brain that is available in the literature, many candidate glutamatergic circuits could be clarified, such as the olfactory circuit, hippocampal–septal pathway, corticostriatal pathway, visual pathway, auditory pathway, and granule cell–Purkinje cell pathway. This review summarizes the probable glutamatergic pathways and the distribution of glutamatergic neurons in the pallium of the turtle brain and compares them with those of avian and mammalian brains. The integrated knowledge of glutamatergic pathways serves as the fundamental basis for further functional studies in the turtle brain, which would provide insights on physiological and pathological mechanisms of glutamate regulation as well as neural circuits in different species.
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Affiliation(s)
- Mohammad Tufazzal Hussan
- Department of Neuroscience of Disease, Brain Research Institute, Niigata University, Niigata, Japan
- Department of Anatomy and Histology, Patuakhali Science and Technology University, Barishal, Bangladesh
- *Correspondence: Mohammad Tufazzal Hussan,
| | - Akiko Sakai
- Department of Neuroscience of Disease, Brain Research Institute, Niigata University, Niigata, Japan
| | - Hideaki Matsui
- Department of Neuroscience of Disease, Brain Research Institute, Niigata University, Niigata, Japan
- Hideaki Matsui,
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3
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Exertier C, Montemiglio LC, Freda I, Gugole E, Parisi G, Savino C, Vallone B. Neuroglobin, clues to function and mechanism. Mol Aspects Med 2021; 84:101055. [PMID: 34876274 DOI: 10.1016/j.mam.2021.101055] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 11/23/2021] [Accepted: 11/24/2021] [Indexed: 12/19/2022]
Abstract
Neuroglobin is expressed in vertebrate brain and belongs to a branch of the globin family that diverged early in evolution. Sequence conservation and presence in nervous cells of several taxa suggests a relevant role in the nervous system, with tight structural restraints. Twenty years after its discovery, a rich scientific literature provides convincing evidence of the involvement of neuroglobin in sustaining neuron viability in physiological and pathological conditions however, a full and conclusive picture of its specific function, or set of functions is still lacking. The difficulty of unambiguously assigning a precise mechanism and biochemical role to neuroglobin might arise from the participation to one or more cell mechanism that redundantly guarantee the functioning of the highly specialized and metabolically demanding central nervous system of vertebrates. Here we collect findings and hypotheses arising from recent biochemical, biophysical, structural, in cell and in vivo experimental work on neuroglobin, aiming at providing an overview of the most recent literature. Proteins are said to have jobs and hobbies, it is possible that, in the case of neuroglobin, evolution has selected for it more than one job, and support to cover for its occasional failings. Disentangling the mechanisms and roles of neuroglobin is thus a challenging task that might be achieved by considering data from different disciplines and experimental approaches.
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Affiliation(s)
- Cécile Exertier
- Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza, Università di Roma, P.le A. Moro 5, 00185, Rome, Italy
| | - Linda Celeste Montemiglio
- Institute of Molecular Biology and Pathology, National Research Council, P.le A. Moro 5, 00185, Rome, Italy
| | - Ida Freda
- Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza, Università di Roma, P.le A. Moro 5, 00185, Rome, Italy
| | - Elena Gugole
- Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza, Università di Roma, P.le A. Moro 5, 00185, Rome, Italy
| | - Giacomo Parisi
- Center for Life Nanoscience, Istituto Italiano di Tecnologia, 00161, Rome, Italy
| | - Carmelinda Savino
- Institute of Molecular Biology and Pathology, National Research Council, P.le A. Moro 5, 00185, Rome, Italy.
| | - Beatrice Vallone
- Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza, Università di Roma, P.le A. Moro 5, 00185, Rome, Italy.
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4
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Neuroglobin Expression Models as a Tool to Study Its Function. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:5728129. [PMID: 31320982 PMCID: PMC6607734 DOI: 10.1155/2019/5728129] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Accepted: 05/12/2019] [Indexed: 01/13/2023]
Abstract
Neuroglobin (Ngb) is an evolutionary conserved member of the globin family with a primary expression in neurons of which the exact functions remain elusive. A plethora of in vivo and in vitro model systems has been generated to this day to determine the functional biological roles of Ngb. Here, we provide a comprehensive overview and discussion of the different Ngb models, covering animal and cellular models of both overexpression and knockout strategies. Intriguingly, an in-depth literature search of available Ngb expression models revealed crucial discrepancies in the outcomes observed in different models. Not only does the level of Ngb expression—either physiologically, overexpressed, or downregulated—alter its functional properties, the experimental setup, being in vitro or in vivo, does impact the functional outcome as well and, hence, whether or not a physiological and/or therapeutic role is ascribed to Ngb. These differences could highlight either technical or biological adaptations and should be considered until elucidation of the Ngb biology.
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5
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Dai JL, Lin Y, Yuan YJ, Xing ST, Xu Y, Zhang QH, Min JK. Regulatory effect of neuroglobin in the recovery of spinal cord injury. J Spinal Cord Med 2019; 42:371-377. [PMID: 29141514 PMCID: PMC6522911 DOI: 10.1080/10790268.2017.1397874] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVE The present study was aimed to investigate the therapeutic potential of neuroglobin in the recovery of spinal cord injury. METHODS The male albino Wistar strain rats were used as an experimental model, and adeno associated virus (AAV) was administered in the T12 section of spinal cord ten days prior to the injury. Basso Beattie Bresnahan (BBB) locomotor rating scale was used to determine the recovery of the hind limb during four weeks post-operation. Malondialdehyde (MDA), catalase and superoxide dismutase (SOD) were determined in the spinal cord tissues. Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay was carried out to determine the presence of apoptotic cells. Immunofluorescence analysis was carried out to determine the neuroglobin expression. Western blot analysis was carried out to determine the protein expressions of caspase-3, cytochrome c, bax and bcl-2 in the spinal cord tissues. RESULTS Experimental results showed that rats were recovered from the spinal cord injury due to increased neuroglobin expression. Lipid peroxidation was reduced, whereas catalase and SOD activity were increased in the spinal cord tissues. Apoptosis and lesions were significantly reduced in the spinal cord tissues. Caspase-3, cytochrome c and bax levels were significantly reduced, whereas bcl-2 expression was reduced in the spinal cord tissues. CONCLUSION Taking all these data together, it is suggested that the increased neuroglobin expression could improve the locomotor function.
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Affiliation(s)
- Ji-Lin Dai
- Department of Orthopaedic, Huzhou First People's Hospital of Zhejiang Province, Huzhou City313000, China
| | - Yun Lin
- Department of Editor, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu610072, China
| | - Yong-Jian Yuan
- Department of Orthopaedic, Huzhou First People's Hospital of Zhejiang Province, Huzhou City313000, China
| | - Shi-Tong Xing
- Department of Orthopaedic, Huzhou First People's Hospital of Zhejiang Province, Huzhou City313000, China
| | - Yi Xu
- Department of Orthopaedic, Huzhou First People's Hospital of Zhejiang Province, Huzhou City313000, China
| | - Qiang-Hua Zhang
- Department of Orthopaedic, Huzhou First People's Hospital of Zhejiang Province, Huzhou City313000, China
| | - Ji-Kang Min
- Department of Orthopaedic, Huzhou First People's Hospital of Zhejiang Province, Huzhou City313000, China,Correspondence to: Ji-Kang Min, Department of Orthopaedic, Huzhou First People’s Hospital of Zhejiang Province, No 158 Square posterior Road, Huzhou City 313000, China. Tel 0086-572-2039275,
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6
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Van Acker ZP, Luyckx E, Dewilde S. Neuroglobin Expression in the Brain: a Story of Tissue Homeostasis Preservation. Mol Neurobiol 2018; 56:2101-2122. [DOI: 10.1007/s12035-018-1212-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 06/26/2018] [Indexed: 12/19/2022]
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7
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Fago A. Functional roles of globin proteins in hypoxia-tolerant ectothermic vertebrates. J Appl Physiol (1985) 2017; 123:926-934. [PMID: 28428250 DOI: 10.1152/japplphysiol.00104.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 03/28/2017] [Accepted: 04/16/2017] [Indexed: 11/22/2022] Open
Abstract
Globins are heme-containing proteins ubiquitously expressed in vertebrates, where they serve a broad range of biological functions, directly or indirectly related to the tight control of oxygen levels and its toxic products in vivo. Perhaps the most investigated of all proteins, hemoglobin and myoglobin are primarily involved in oxygen transport and storage, but also in facilitating arterial vasodilation, suppressing mitochondrial respiration, and preventing tissue oxidative damage via accessory redox enzymatic activities during hypoxia. By contrast, the more recently discovered neuroglobin and cytoglobin do not seem to function as reversible oxygen carriers and are instead involved in redox activities, although their exact biological roles remain to be clarified. In this context, hypoxia-tolerant ectotherms, such as freshwater turtles and members of the carp family that survive winter in extreme hypoxia, have proven as excellent models to appreciate the diversity of biological functions of globin proteins. Unraveling physiological roles of globin proteins in these extreme animals will clarify an important part of the adaptive mechanisms for surviving extreme fluctuations of oxygen availability that are prohibitive to mammals.
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Affiliation(s)
- Angela Fago
- Department of Bioscience, Aarhus University, Aarhus, Denmark
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8
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Tekko T, Lakspere T, Allikalt A, End J, Kõlvart KR, Jagomäe T, Terasmaa A, Philips MA, Visnapuu T, Väärtnõu F, Gilbert SF, Rinken A, Vasar E, Lilleväli K. Wfs1 is expressed in dopaminoceptive regions of the amniote brain and modulates levels of D1-like receptors. PLoS One 2017; 12:e0172825. [PMID: 28267787 PMCID: PMC5436468 DOI: 10.1371/journal.pone.0172825] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 02/10/2017] [Indexed: 11/27/2022] Open
Abstract
During amniote evolution, the construction of the forebrain has diverged across
different lineages, and accompanying the structural changes, functional
diversification of the homologous brain regions has occurred. This can be
assessed by studying the expression patterns of marker genes that are relevant
in particular functional circuits. In all vertebrates, the dopaminergic system
is responsible for the behavioral responses to environmental stimuli. Here we
show that the brain regions that receive dopaminergic input through dopamine
receptor D1 are relatively conserved, but with some important
variations between three evolutionarily distant vertebrate lines–house mouse
(Mus musculus), domestic chick (Gallus gallus
domesticus) / common quail (Coturnix coturnix) and
red-eared slider turtle (Trachemys scripta). Moreover, we find
that in almost all instances, those brain regions expressing D1-like dopamine
receptor genes also express Wfs1. Wfs1 has been studied
primarily in the pancreas, where it regulates the endoplasmic reticulum (ER)
stress response, cellular Ca2+ homeostasis, and insulin production
and secretion. Using radioligand binding assays in wild type and
Wfs1-/- mouse brains, we show that the number of
binding sites of D1-like dopamine receptors is increased in the hippocampus of
the mutant mice. We propose that the functional link between Wfs1 and D1-like
dopamine receptors is evolutionarily conserved and plays an important role in
adjusting behavioral reactions to environmental stimuli.
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Affiliation(s)
- Triin Tekko
- Department of Physiology, Institute of Biomedicine and Translational
Medicine, University of Tartu, Tartu, Estonia
- Centre of Excellence in Genomics and Translational Medicine, University
of Tartu, Tartu, Estonia
| | - Triin Lakspere
- Department of Developmental Biology, Institute of Molecular and Cell
Biology, University of Tartu, Tartu, Estonia
| | - Anni Allikalt
- Institute of Chemistry, University of Tartu, Tartu,
Estonia
| | - Jaanus End
- Department of Developmental Biology, Institute of Molecular and Cell
Biology, University of Tartu, Tartu, Estonia
| | | | - Toomas Jagomäe
- Department of Physiology, Institute of Biomedicine and Translational
Medicine, University of Tartu, Tartu, Estonia
- Centre of Excellence in Genomics and Translational Medicine, University
of Tartu, Tartu, Estonia
| | - Anton Terasmaa
- Department of Physiology, Institute of Biomedicine and Translational
Medicine, University of Tartu, Tartu, Estonia
- Centre of Excellence in Genomics and Translational Medicine, University
of Tartu, Tartu, Estonia
| | - Mari-Anne Philips
- Department of Physiology, Institute of Biomedicine and Translational
Medicine, University of Tartu, Tartu, Estonia
- Centre of Excellence in Genomics and Translational Medicine, University
of Tartu, Tartu, Estonia
| | - Tanel Visnapuu
- Department of Physiology, Institute of Biomedicine and Translational
Medicine, University of Tartu, Tartu, Estonia
- Centre of Excellence in Genomics and Translational Medicine, University
of Tartu, Tartu, Estonia
| | - Fred Väärtnõu
- Department of Developmental Biology, Institute of Molecular and Cell
Biology, University of Tartu, Tartu, Estonia
| | - Scott F. Gilbert
- Department of Biology, Swarthmore College, Swarthmore, PA, United States
of America
| | - Ago Rinken
- Institute of Chemistry, University of Tartu, Tartu,
Estonia
| | - Eero Vasar
- Department of Physiology, Institute of Biomedicine and Translational
Medicine, University of Tartu, Tartu, Estonia
- Centre of Excellence in Genomics and Translational Medicine, University
of Tartu, Tartu, Estonia
| | - Kersti Lilleväli
- Department of Physiology, Institute of Biomedicine and Translational
Medicine, University of Tartu, Tartu, Estonia
- Centre of Excellence in Genomics and Translational Medicine, University
of Tartu, Tartu, Estonia
- * E-mail:
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9
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Valentin-Kahan A, García-Tejedor GB, Robello C, Trujillo-Cenóz O, Russo RE, Alvarez-Valin F. Gene Expression Profiling in the Injured Spinal Cord of Trachemys scripta elegans: An Amniote with Self-Repair Capabilities. Front Mol Neurosci 2017; 10:17. [PMID: 28223917 PMCID: PMC5293771 DOI: 10.3389/fnmol.2017.00017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 01/12/2017] [Indexed: 12/19/2022] Open
Abstract
Slider turtles are the only known amniotes with self-repair mechanisms of the spinal cord that lead to substantial functional recovery. Their strategic phylogenetic position makes them a relevant model to investigate the peculiar genetic programs that allow anatomical reconnection in some vertebrate groups but are absent in others. Here, we analyze the gene expression profile of the response to spinal cord injury (SCI) in the turtle Trachemys scripta elegans. We found that this response comprises more than 1000 genes affecting diverse functions: reaction to ischemic insult, extracellular matrix re-organization, cell proliferation and death, immune response, and inflammation. Genes related to synapses and cholesterol biosynthesis are down-regulated. The analysis of the evolutionary distribution of these genes shows that almost all are present in most vertebrates. Additionally, we failed to find genes that were exclusive of regenerating taxa. The comparison of expression patterns among species shows that the response to SCI in the turtle is more similar to that of mice and non-regenerative Xenopus than to Xenopus during its regenerative stage. This observation, along with the lack of conserved “regeneration genes” and the current accepted phylogenetic placement of turtles (sister group of crocodilians and birds), indicates that the ability of spinal cord self-repair of turtles does not represent the retention of an ancestral vertebrate character. Instead, our results suggest that turtles developed this capability from a non-regenerative ancestor (i.e., a lineage specific innovation) that was achieved by re-organizing gene expression patterns on an essentially non-regenerative genetic background. Among the genes activated by SCI exclusively in turtles, those related to anoxia tolerance, extracellular matrix remodeling, and axonal regrowth are good candidates to underlie functional recovery.
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Affiliation(s)
- Adrián Valentin-Kahan
- Department of Cellular and Molecular Neurophysiology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Gabriela B García-Tejedor
- Department of Cellular and Molecular Neurophysiology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Carlos Robello
- Molecular Biology Unit, Institut Pasteur de MontevideoMontevideo, Uruguay; Departamento de Bioquímica, Facultad de Medicina, Universidad de la RepublicaMontevideo, Uruguay
| | - Omar Trujillo-Cenóz
- Department of Cellular and Molecular Neurophysiology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Raúl E Russo
- Department of Cellular and Molecular Neurophysiology, Instituto de Investigaciones Biológicas Clemente Estable Montevideo, Uruguay
| | - Fernando Alvarez-Valin
- Sección Biomatemática, Unidad de Genómica Evolutiva, Facultad de Ciencias, Universidad de la República Montevideo, Uruguay
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10
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Critical re-evaluation of neuroglobin expression reveals conserved patterns among mammals. Neuroscience 2016; 337:339-354. [DOI: 10.1016/j.neuroscience.2016.07.042] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 07/26/2016] [Accepted: 07/26/2016] [Indexed: 01/08/2023]
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11
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Nathaniel TI, Williams-Hernandez A, Hunter AL, Liddy C, Peffley DM, Umesiri FE, Imeh-Nathaniel A. Tissue hypoxia during ischemic stroke: adaptive clues from hypoxia-tolerant animal models. Brain Res Bull 2015; 114:1-12. [PMID: 25738761 DOI: 10.1016/j.brainresbull.2015.02.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Revised: 02/12/2015] [Accepted: 02/19/2015] [Indexed: 10/23/2022]
Abstract
The treatment and prevention of hypoxic/ischemic brain injury in stroke patients remain a severe and global medical issue. Numerous clinical studies have resulted in a failure to develop chemical neuroprotection for acute, ischemic stroke. Over 150 estimated clinical trials of ischemic stroke treatments have been done, and more than 200 drugs and combinations of drugs for ischemic and hemorrhagic strokes have been developed. Billions of dollars have been invested for new scientific breakthroughs with only limited success. The revascularization of occluded cerebral arteries such as anti-clot treatments of thrombolysis has proven effective, but it can only be used in a 3-4.5h time frame after the onset of a stroke, and not for every patient. This review is about novel insights on how to resist tissue hypoxia from unconventional animal models. Ability to resist tissue hypoxia is an extraordinary ability that is not common in many laboratory animals such as rat and mouse models. For example, we can learn from a naked mole-rat, Chrysemys picta, how to actively regulate brain metabolic activity to defend the brain against fluctuating oxygen tension and acute bouts of oxidative stress following the onset of a stroke. Additionally, a euthermic arctic ground squirrel can teach us how the brain of a stroke patient can remain well oxygenated during tissue hypoxia with no evidence of cellular stress. In this review, we discuss how these animals provide us with a system to gain insight into the possible mechanisms of tissue hypoxia/ischemia. This issue is of clinical significance to stroke patients. We describe specific physiological and molecular adaptations employed by different animals' models of hypoxia tolerance in aquatic and terrestrial environments. We highlight how these adaptations might provide potential clues on strategies to adapt for the clinical management of tissue hypoxia during conditions such as stroke where oxygen demand fails to match the supply.
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Affiliation(s)
- Thomas I Nathaniel
- University of South Carolina School of Medicine-Greenville, 701 Grove Road, Greenville, SC 29605, United States.
| | - Ashley Williams-Hernandez
- University of South Carolina School of Medicine-Greenville, 701 Grove Road, Greenville, SC 29605, United States
| | - Anan L Hunter
- University of South Carolina School of Medicine-Greenville, 701 Grove Road, Greenville, SC 29605, United States
| | - Caroline Liddy
- University of South Carolina School of Medicine-Greenville, 701 Grove Road, Greenville, SC 29605, United States
| | - Dennis M Peffley
- University of South Carolina School of Medicine-Greenville, 701 Grove Road, Greenville, SC 29605, United States
| | - Francis E Umesiri
- Chemistry department, John Brown University, 2000 W. University Street, Siloam Springs, AR 72761, United States
| | - Adebobola Imeh-Nathaniel
- Department of Biology, North Greenville University, 7801 North Tigerville Road, Tigerville, SC 29688, United States
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12
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Götting M, Nikinmaa M. More than hemoglobin - the unexpected diversity of globins in vertebrate red blood cells. Physiol Rep 2015; 3:3/2/e12284. [PMID: 25649247 PMCID: PMC4393193 DOI: 10.14814/phy2.12284] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
In many multicellular organisms, oxygen is transported by respiratory proteins, which are globins in vertebrates, between respiratory organs and tissues. In jawed vertebrates, eight globins are known which are expressed in a highly tissue-specific manner. Until now, hemoglobin (Hb) had been agreed to be the only globin expressed in vertebrate erythrocytes. Here, we investigate for the first time the mRNA expression of globin genes in nucleated and anucleated erythrocytes of model vertebrate species by quantitative real-time reverse transcription PCR (qRT-PCR). Surprisingly, we found transcripts of the whole gnathostome globin superfamily in RBCs. The mRNA expression levels varied among species, with Hb being by far the dominant globin. Only in stickleback, a globin previously thought to be neuron-specific, neuroglobin, had higher mRNA expression. We furthermore show that in birds transcripts of globin E, which was earlier reported to be transcribed only in the eye, are also present in RBCs. Even in anucleated RBCs of mammals, we found transcripts of myoglobin, neuroglobin, and cytoglobin. Our findings add new aspects to the current knowledge on the expression of globins in vertebrate tissues. However, whether or not the mRNA expression of these globin genes has any functional significance in RBCs has to be investigated in future studies.
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Affiliation(s)
- Miriam Götting
- Zoological Institute and Zoological Museum, Biocenter Grindel, University of Hamburg, Hamburg, Germany
| | - Mikko Nikinmaa
- Department of Biology, Laboratory of Animal Physiology, University of Turku, Turku, Finland
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13
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Larson J, Drew KL, Folkow LP, Milton SL, Park TJ. No oxygen? No problem! Intrinsic brain tolerance to hypoxia in vertebrates. ACTA ACUST UNITED AC 2014; 217:1024-39. [PMID: 24671961 DOI: 10.1242/jeb.085381] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many vertebrates are challenged by either chronic or acute episodes of low oxygen availability in their natural environments. Brain function is especially vulnerable to the effects of hypoxia and can be irreversibly impaired by even brief periods of low oxygen supply. This review describes recent research on physiological mechanisms that have evolved in certain vertebrate species to cope with brain hypoxia. Four model systems are considered: freshwater turtles that can survive for months trapped in frozen-over lakes, arctic ground squirrels that respire at extremely low rates during winter hibernation, seals and whales that undertake breath-hold dives lasting minutes to hours, and naked mole-rats that live in crowded burrows completely underground for their entire lives. These species exhibit remarkable specializations of brain physiology that adapt them for acute or chronic episodes of hypoxia. These specializations may be reactive in nature, involving modifications to the catastrophic sequelae of oxygen deprivation that occur in non-tolerant species, or preparatory in nature, preventing the activation of those sequelae altogether. Better understanding of the mechanisms used by these hypoxia-tolerant vertebrates will increase appreciation of how nervous systems are adapted for life in specific ecological niches as well as inform advances in therapy for neurological conditions such as stroke and epilepsy.
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Affiliation(s)
- John Larson
- Psychiatric Institute, Department of Psychiatry and Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois, Chicago, IL 60612, USA
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Affiliation(s)
- Luisa B. Maia
- REQUIMTE/CQFB, Departamento
de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - José J. G. Moura
- REQUIMTE/CQFB, Departamento
de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
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Lan WB, Lin JH, Chen XW, Wu CY, Zhong GX, Zhang LQ, Lin WP, Liu WN, Li X, Lin JL. Overexpressing neuroglobin improves functional recovery by inhibiting neuronal apoptosis after spinal cord injury. Brain Res 2014; 1562:100-8. [PMID: 24675030 DOI: 10.1016/j.brainres.2014.03.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 02/08/2014] [Accepted: 03/17/2014] [Indexed: 01/10/2023]
Abstract
The current study was performed to evaluate the mechanisms and therapeutic effects of overexpressing neuroglobin (Ngb) on spinal cord injury (SCI). Adeno-associated virus (AAV) was injected in the T12 section 7 days before SCI. Animals were randomly divided into four groups: a sham group, a vehicle group, an AAV-EGFP group and an AAV-Ngb group. Recovery of hind limb locomotor function was determined during the 3-week post operation period by the Basso, Beattie and Bresnahan locomotor rating scale. At 24 h after SCI and at the end of the study, the segments of spinal cord, centered with the lesion site were harvested for histopathological analysis. Immunofluorescence was performed using antibodies to recognize neuN in the lesion sections. At 24 h after SCI, the spinal cord tissue samples were removed to analyze tissue concentrations of superoxide dismutase (SOD) and malondialdehyde (MDA). Apoptotic cells were assessed using a terminal deoxynucleotidyl transferase, dUTP nick end labeling (TUNEL) kit. The expression of bcl-2, bax, cytochrome c, and cleaved caspase-3, were determined by Western blot assay and immunostaining analysis. The results showed that animals overexpressing Ngb had significantly greater recovery of locomotor function, less neuronal loss and fewer apoptotic cells. In addition, overexpressing Ngb significantly increased bcl-2 expression and SOD level, decreased bax expression, attenuated the release of cytochrome c from mitochondria to the cytosol fraction, and reduced the activity of caspase-3 and MDA level after SCI. These findings suggest, that overexpressing Ngb can significantly improve the recovery of locomotor function. This neuroprotective effect may be associated with the inhibition of neural apoptosis via the mitochondrial pathway.
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Affiliation(s)
- Wen-Bin Lan
- The First Clinical Medical College of Fujian Medical University, Fuzhou, Fujian, China
| | - Jian-Hua Lin
- The First Clinical Medical College of Fujian Medical University, Fuzhou, Fujian, China.
| | - Xuan-Wei Chen
- The First Clinical Medical College of Fujian Medical University, Fuzhou, Fujian, China
| | - Chao-Yang Wu
- The First Clinical Medical College of Fujian Medical University, Fuzhou, Fujian, China
| | - Guang-Xian Zhong
- The First Clinical Medical College of Fujian Medical University, Fuzhou, Fujian, China
| | - Li-Qun Zhang
- The First Clinical Medical College of Fujian Medical University, Fuzhou, Fujian, China
| | - Wen-Ping Lin
- Department of Orthopedics, the 2nd Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
| | - Wei-Nan Liu
- Department of Orthopedics, the Affiliated People׳s Hospital of Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, China
| | - Xiang Li
- The First Clinical Medical College of Fujian Medical University, Fuzhou, Fujian, China
| | - Jin-Luan Lin
- The First Clinical Medical College of Fujian Medical University, Fuzhou, Fujian, China
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Nathaniel TI, Otukonyong EE, Okon M, Chaves J, Cochran T, Nathaniel AI. Metabolic regulatory clues from the naked mole rat: toward brain regulatory functions during stroke. Brain Res Bull 2013; 98:44-52. [PMID: 23886571 DOI: 10.1016/j.brainresbull.2013.07.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 07/03/2013] [Accepted: 07/15/2013] [Indexed: 12/30/2022]
Abstract
Resistance to tissue hypoxia is a robust fundamental adaptation to low oxygen supply, and represents a novel neuroscience problem with significance to mammalian physiology as well as human health. With the underlying mechanisms strongly conserved in evolution, the ability to resist tissue hypoxia in natural systems has recently emerged as an interesting model in mammalian physiology research to understand mechanisms that can be manipulated for the clinical management of stroke. The extraordinary ability to resist tissue hypoxia by the naked mole rat (NMR) indicates the presence of a unique mechanism that underlies the remarkable healthy life span and exceptional hypoxia resistance. This opens an interesting line of research into understanding the mechanisms employed by the naked mole rat (Heterocephalus glaber) to protect the brain during hypoxia. In a series of studies, we first examined the presence of neuroprotection in the brain cells of naked mole rats (NMRs) subjected to hypoxic insults, and then characterized the expression of such neuroprotection in a wide range of time intervals. We used oxygen nutrient deprivation (OND), an in vitro model of resistance to tissue hypoxia to determine whether there is evidence of neuronal survival in the hippocampal (CA1) slices of NMRs that are subjected to chronic hypoxia. Hippocampus neurons of NMRs that were kept in hypoxic condition consistently tolerated OND right from the onset time of 5h. This tolerance was maintained for 24h. This finding indicates that there is evidence of resistance to tissue hypoxia by CA1 neurons of NMRs. We further examined the effect of hypoxia on metabolic rate in the NMR. Repeated measurement of metabolic rates during exposure of naked mole rats to hypoxia over a constant ambient temperature indicates that hypoxia significantly decreased metabolic rates in the NMR, suggesting that the observed decline in metabolic rate during hypoxia may contribute to the adaptive mechanism used by the NMR to resist tissue hypoxia. This work is aimed to contribute to the understanding of mechanisms of resistance to tissue hypoxia in the NMR as an important life-sustaining process, which can be translated into therapeutic interventions during stroke.
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Affiliation(s)
- Thomas I Nathaniel
- University of South Carolina School of Medicine, HSEB, 607 Grove Road, Greenville, SC 29605, United States.
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Sifuentes-Romero I, Merchant-Larios H, Milton SL, Moreno-Mendoza N, Díaz-Hernández V, García-Gasca A. RNAi-Mediated Gene Silencing in a Gonad Organ Culture to Study Sex Determination Mechanisms in Sea Turtle. Genes (Basel) 2013; 4:293-305. [PMID: 24705165 PMCID: PMC3899968 DOI: 10.3390/genes4020293] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 05/15/2013] [Accepted: 05/20/2013] [Indexed: 01/17/2023] Open
Abstract
The autosomal Sry-related gene, Sox9, encodes a transcription factor, which performs an important role in testis differentiation in mammals. In several reptiles, Sox9 is differentially expressed in gonads, showing a significant upregulation during the thermo-sensitive period (TSP) at the male-promoting temperature, consistent with the idea that SOX9 plays a central role in the male pathway. However, in spite of numerous studies, it remains unclear how SOX9 functions during this event. In the present work, we developed an RNAi-based method for silencing Sox9 in an in vitro gonad culture system for the sea turtle, Lepidochelys olivacea. Gonads were dissected as soon as the embryos entered the TSP and were maintained in organ culture. Transfection of siRNA resulted in the decrease of both Sox9 mRNA and protein. Furthermore, we found coordinated expression patterns for Sox9 and the anti-Müllerian hormone gene, Amh, suggesting that SOX9 could directly or indirectly regulate Amh expression, as it occurs in mammals. These results demonstrate an in vitro method to knockdown endogenous genes in gonads from a sea turtle, which represents a novel approach to investigate the roles of important genes involved in sex determination or differentiation pathways in species with temperature-dependent sex determination.
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Affiliation(s)
- Itzel Sifuentes-Romero
- Laboratory of Molecular Biology, Research Centre for Nutrition and Development (CIAD), Avenida Sábalo-Cerritos s/n, Mazatlán, Sinaloa 82010, Mexico.
| | - Horacio Merchant-Larios
- Institute for Biomedical Research, Universidad Nacional Autónoma de México (UNAM), Mexico City 04510, Mexico.
| | - Sarah L Milton
- Department of Biological Sciences, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431, USA.
| | - Norma Moreno-Mendoza
- Institute for Biomedical Research, Universidad Nacional Autónoma de México (UNAM), Mexico City 04510, Mexico.
| | - Verónica Díaz-Hernández
- Department of Embryology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Mexico City 04510, Mexico.
| | - Alejandra García-Gasca
- Laboratory of Molecular Biology, Research Centre for Nutrition and Development (CIAD), Avenida Sábalo-Cerritos s/n, Mazatlán, Sinaloa 82010, Mexico.
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Milton SL, Dawson-Scully K. Alleviating brain stress: what alternative animal models have revealed about therapeutic targets for hypoxia and anoxia. FUTURE NEUROLOGY 2013; 8:287-301. [PMID: 25264428 DOI: 10.2217/fnl.13.12] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
While the mammalian brain is highly dependent on oxygen, and can withstand only a few minutes without air, there are both vertebrate and invertebrate examples of anoxia tolerance. One example is the freshwater turtle, which can withstand days without oxygen, thus providing a vertebrate model with which to examine the physiology of anoxia tolerance without the pathology seen in mammalian ischemia/reperfusion studies. Insect models such as Drosophila melanogaster have additional advantages, such as short lifespans, low cost and well-described genetics. These models of anoxia tolerance share two common themes that enable survival without oxygen: entrance into a state of deep hypometabolism, and the suppression of cellular injury during anoxia and upon restoration of oxygen. The study of such models of anoxia tolerance, adapted through millions of years of evolution, may thus suggest protective pathways that could serve as therapeutic targets for diseases characterized by oxygen deprivation and ischemic/reperfusion injuries.
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Affiliation(s)
- Sarah L Milton
- Department of Biological Sciences, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431, USA
| | - Ken Dawson-Scully
- Department of Biological Sciences, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431, USA
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Wang J, Zhang W, Sun D, Song L, Li Y, Xu C. Analysis of neuroglobin mRNA expression in rat brain due to arsenite-induced oxidative stress. ENVIRONMENTAL TOXICOLOGY 2012; 27:503-509. [PMID: 22887765 DOI: 10.1002/tox.20664] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 09/12/2010] [Accepted: 09/21/2010] [Indexed: 06/01/2023]
Abstract
Arsenic (As) in drinking water is a toxicant causing several health problems including nervous system disturbance. Neuroglobin (Ngb) is a tissue globin in nervous system playing protective role against oxidative stress in many injuries. This study was to investigate how long arsenite exposure (sodium arsenite 7.5 mg/kg/day) could induce oxidative stress in blood and brain of rats and to determine whether Ngb expression in rat brain changed due to oxidative stress. Results showed that superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in serum and brain homogenates and reactive oxygen species (ROS) generation in red blood cells (RBCs) did not change in the rats exposed to arsenite for 8 weeks. In the rats exposed to arsenite for 16 weeks, SOD activity decreased (serum: P < 0.05; brain homogenates: P < 0.01) and MDA level increased (P < 0.01) in serum and brain homogenates; ROS production increased (P < 0.01) in RBC. When oxidative stress occurred, Ngb mRNA expression did not change in whole brain, cerebral cortex, midbrain, and hippocampus; however, Ngb mRNA expression increased significantly (P < 0.05) in cerebellum compared to the control group. This study suggests that arsenite exposure for 16 weeks can lead to oxidative stress of blood and brain of rats. Ngb may play a protective role in cerebellum when oxidative stress occurs due to arsenite exposure.
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Affiliation(s)
- Jing Wang
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, China
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Post-transcriptional gene silencing by RNA interference in non-mammalian vertebrate systems: Where do we stand? MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2011; 728:158-71. [DOI: 10.1016/j.mrrev.2011.09.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2011] [Revised: 09/02/2011] [Accepted: 09/06/2011] [Indexed: 12/20/2022]
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EPR investigation of the role of B10 phenylalanine in neuroglobin — Evidence that B10Phe mediates structural changes in the heme region upon disulfide-bridge formation. J Inorg Biochem 2011; 105:1131-7. [DOI: 10.1016/j.jinorgbio.2011.05.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 05/31/2011] [Accepted: 05/31/2011] [Indexed: 11/18/2022]
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Dietz GPH. Protection by neuroglobin and cell-penetrating peptide-mediated delivery in vivo: a decade of research. Comment on Cai et al: TAT-mediated delivery of neuroglobin protects against focal cerebral ischemia in mice. Exp Neurol. 2011; 227(1): 224-31. Exp Neurol 2011; 231:1-10. [PMID: 21620833 DOI: 10.1016/j.expneurol.2011.05.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 05/04/2011] [Accepted: 05/10/2011] [Indexed: 12/09/2022]
Abstract
Over the last decade, numerous studies have suggested that neuroglobin is able to protect against the effects of ischemia. However, such results have mostly been based on models using transgenic overexpression or viral delivery. As a therapy, new technology would need to be applied to enable delivery of high concentrations of neuroglobin shortly after the patient suffers the stroke. An approach to deliver proteins in ischemia in vivo in a timely manner is the use of cell-penetrating peptides (CPP). CPP have been used in animal models for brain diseases for about a decade as well. In a recent issue of Experimental Neurology, Cai and colleagues test the effect of CPP-coupled neuroglobin in an in vivo stroke model. They find that the fusion protein protects the brain against the effect of ischemia when applied before stroke onset. Here, a concise review of neuroglobin research and the application of CPP peptides in hypoxia and ischemia is provided.
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Affiliation(s)
- Gunnar P H Dietz
- Dep. 851, Neurodegeneration II, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark.
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Neuroglobin, cytoglobin, and myoglobin contribute to hypoxia adaptation of the subterranean mole rat Spalax. Proc Natl Acad Sci U S A 2010; 107:21570-5. [PMID: 21115824 DOI: 10.1073/pnas.1015379107] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The subterranean mole rat Spalax is an excellent model for studying adaptation of a mammal toward chronic environmental hypoxia. Neuroglobin (Ngb) and cytoglobin (Cygb) are O(2)-binding respiratory proteins and thus candidates for being involved in molecular hypoxia adaptations of Spalax. Ngb is expressed primarily in vertebrate nerves, whereas Cygb is found in extracellular matrix-producing cells and in some neurons. The physiological functions of both proteins are not fully understood but discussed with regard to O(2) supply, the detoxification of reactive oxygen or nitrogen species, and apoptosis protection. Spalax Ngb and Cygb coding sequences are strongly conserved. However, mRNA and protein levels of Ngb in Spalax brain are 3-fold higher than in Rattus norvegicus under normoxia. Importantly, Spalax expresses Ngb in neurons and additionally in glia, whereas in hypoxia-sensitive rodents Ngb expression is limited to neurons. Hypoxia causes an approximately 2-fold down-regulation of Ngb mRNA in brain of rat and mole rat. A parallel regulatory response was found for myoglobin (Mb) in Spalax and rat muscle, suggesting similar functions of Mb and Ngb. Cygb also revealed an augmented normoxic expression in Spalax vs. rat brain, but not in heart or liver, indicating distinct tissue-specific functions. Hypoxia induced Cygb transcription in heart and liver of both mammals, with the most prominent mRNA up-regulation (12-fold) in Spalax heart. Our data suggest that tissue globins contribute to the remarkable tolerance of Spalax toward environmental hypoxia. This is consistent with the proposed cytoprotective effect of Ngb and Cygb under pathological hypoxic/ischemic conditions in mammals.
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Li W, Wu Y, Ren C, Lu Y, Gao Y, Zheng X, Zhang C. The activity of recombinant human neuroglobin as an antioxidant and free radical scavenger. Proteins 2010; 79:115-25. [DOI: 10.1002/prot.22863] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Revised: 08/14/2010] [Accepted: 08/23/2010] [Indexed: 11/06/2022]
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