1
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Ruffini A, Dvoriashyna M, Govetto A, Romano MR, Repetto R. A Mathematical Model of Interstitial Fluid Flow and Retinal Tissue Deformation in Macular Edema. Invest Ophthalmol Vis Sci 2024; 65:19. [PMID: 39254963 PMCID: PMC11401122 DOI: 10.1167/iovs.65.11.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/11/2024] Open
Abstract
Purpose This study aims to develop a mathematical model to elucidate fluid circulation in the retina, focusing on the movement of interstitial fluid (comprising water and albumin) to understand the mechanisms underlying exudative macular edema (EME). Methods The model integrates physiological factors such as retinal pigment epithelium (RPE) pumping, osmotic pressure gradients, and tissue deformation. It accounts for spatial variability in hydraulic conductivity (HC) across the retina and incorporates the structural role of Müller cells (MCs) in maintaining retinal stability. Results The model predicts that tissue deformation is maximal at the center of the fovea despite fluid exudation from blood capillaries occurring elsewhere, aligning with clinical observations. Additionally, the model suggests that spatial variability in HC across the thickness of the retina plays a protective role against fluid accumulation in the fovea. Conclusions Despite inherent simplifications and uncertainties in parameter values, this study represents a step toward understanding the pathophysiology of EME. The findings provide insights into the mechanisms underlying fluid dynamics in the retina and fluid accumulation in the foveal region, showing that the specific conformation of Müller cells is likely to play a key role.
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Affiliation(s)
- Alessia Ruffini
- Department of Civil, Chemical and Environmental Engineering, University of Genoa, Genoa, Italy
| | - Mariia Dvoriashyna
- School of Mathematics, University of Edinburgh, Edinburgh, United Kingdom
| | - Andrea Govetto
- Department of Biomedical Sciences, Humanitas University, Milan, Italy
| | - Mario R Romano
- Department of Biomedical Sciences, Humanitas University, Milan, Italy
| | - Rodolfo Repetto
- Department of Civil, Chemical and Environmental Engineering, University of Genoa, Genoa, Italy
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2
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García-García F, Acosta-Hernández ME, Beltrán-Parrazal L, Rodríguez-Alba JC. The Role of Neuroglobin in the Sleep-Wake Cycle. Sleep Sci 2023; 16:e362-e367. [PMID: 38196764 PMCID: PMC10773511 DOI: 10.1055/s-0043-1772806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 11/23/2022] [Indexed: 01/11/2024] Open
Abstract
Neuroglobin (Ngb) is a protein expressed in the central and peripherical nervous systems of the vertebrate. The Ngb has different functions in neurons, including regulating O 2 homeostasis, oxidative stress, and as a neuroprotector after ischemia/hypoxia events. The Ngb is a hemoprotein of the globin family, structurally like myoglobin and hemoglobin. Ngb has higher expression in the cortex, hypothalamus, thalamus, brainstem, and cerebellum in mammals. Interestingly, Ngb immunoreactivity oscillates according to the sleep-wake cycle and decreases after 24 hours of sleep deprivation, suggesting that sleep homeostasis regulates Ngb expression. In addition, Ngb expresses in brain areas related to REM sleep regulation. Therefore, in the present review, we discuss the potential role of the Ngb in the sleep-wake regulation of mammals.
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Affiliation(s)
- Fabio García-García
- Instituto de Ciencias de la Salud, Departamento de Biomedicina, Universidad Veracruzana, Xalapa, Veracruz, Mexico
| | | | - Luis Beltrán-Parrazal
- Instituto de Investigaciones Cerebrales, Universidad Veracruzana, Xalapa, Veracruz, Mexico
| | - Juan Carlos Rodríguez-Alba
- Instituto de Ciencias de la Salud, Departamento de Biomedicina, Universidad Veracruzana, Xalapa, Veracruz, Mexico
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3
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Roberts PA. Inverse Problem Reveals Conditions for Characteristic Retinal Degeneration Patterns in Retinitis Pigmentosa Under the Trophic Factor Hypothesis. Front Aging Neurosci 2022; 14:765966. [PMID: 35585866 PMCID: PMC9108254 DOI: 10.3389/fnagi.2022.765966] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 03/21/2022] [Indexed: 12/05/2022] Open
Abstract
Retinitis pigmentosa (RP) is the most common inherited retinal dystrophy with a prevalence of about 1 in 4,000, affecting approximately 1.5 million people worldwide. Patients with RP experience progressive visual field loss as the retina degenerates, destroying light-sensitive photoreceptor cells (rods and cones), with rods affected earlier and more severely than cones. Spatio-temporal patterns of retinal degeneration in human RP have been well characterised; however, the mechanism(s) giving rise to these patterns have not been conclusively determined. One such mechanism, which has received a wealth of experimental support, is described by the trophic factor hypothesis. This hypothesis suggests that rods produce a trophic factor necessary for cone survival; the loss of rods depletes this factor, leading to cone degeneration. In this article, we formulate a partial differential equation mathematical model of RP in one spatial dimension, spanning the region between the retinal centre (fovea) and the retinal edge (ora serrata). Using this model we derive and solve an inverse problem, revealing for the first time experimentally testable conditions under which the trophic factor mechanism will qualitatively recapitulate the spatio-temporal patterns of retinal regeneration observed in human RP.
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De Simone G, Sbardella D, Oddone F, Pesce A, Coletta M, Ascenzi P. Structural and (Pseudo-)Enzymatic Properties of Neuroglobin: Its Possible Role in Neuroprotection. Cells 2021; 10:cells10123366. [PMID: 34943874 PMCID: PMC8699588 DOI: 10.3390/cells10123366] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/20/2021] [Accepted: 11/23/2021] [Indexed: 12/17/2022] Open
Abstract
Neuroglobin (Ngb), the third member of the globin family, was discovered in human and murine brains in 2000. This monomeric globin is structurally similar to myoglobin (Mb) and hemoglobin (Hb) α and β subunits, but it hosts a bis-histidyl six-coordinated heme-Fe atom. Therefore, the heme-based reactivity of Ngb is modulated by the dissociation of the distal HisE7-heme-Fe bond, which reflects in turn the redox state of the cell. The high Ngb levels (~100–200 μM) present in the retinal ganglion cell layer and in the optic nerve facilitate the O2 buffer and delivery. In contrast, the very low levels of Ngb (~1 μM) in most tissues and organs support (pseudo-)enzymatic properties including NO/O2 metabolism, peroxynitrite and free radical scavenging, nitrite, hydroxylamine, hydrogen sulfide reduction, and the nitration of aromatic compounds. Here, structural and (pseudo-)enzymatic properties of Ngb, which are at the root of tissue and organ protection, are reviewed, envisaging a possible role in the protection from neuronal degeneration of the retina and the optic nerve.
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Affiliation(s)
- Giovanna De Simone
- Dipartimento di Scienze, Università Roma Tre, Viale Marconi 446, 00146 Roma, Italy;
| | | | | | - Alessandra Pesce
- Dipartimento di Fisica, Università di Genova, Via Dodecaneso 33, 16100 Genova, Italy;
| | - Massimo Coletta
- IRCCS Fondazione Bietti, 00198 Roma, Italy; (D.S.); (F.O.)
- Dipartmento di Scienze Cliniche e Medicina Traslazionale, Università di Roma “Tor Vergata”, Via Montpellier 1, 00133 Roma, Italy
- Correspondence: (M.C.); (P.A.); Tel.: +39-06-72596365 (M.C.); +39-06-57336321 (P.A.)
| | - Paolo Ascenzi
- Dipartimento di Scienze, Università Roma Tre, Viale Marconi 446, 00146 Roma, Italy;
- Accademia Nazionale dei Lincei, Via della Lungara 10, 00165 Roma, Italy
- Unità di Neuroendocrinologia, Metabolismo e Neurofarmacologia, IRCSS Fondazione Santa Lucia, 00179 Roma, Italy
- Correspondence: (M.C.); (P.A.); Tel.: +39-06-72596365 (M.C.); +39-06-57336321 (P.A.)
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5
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Solar Fernandez V, Marino M, Fiocchetti M. Neuroglobin in Retinal Neurodegeneration: A Potential Target in Therapeutic Approaches. Cells 2021; 10:cells10113200. [PMID: 34831423 PMCID: PMC8621852 DOI: 10.3390/cells10113200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/09/2021] [Accepted: 11/15/2021] [Indexed: 12/12/2022] Open
Abstract
Retinal neurodegeneration affects an increasing number of people worldwide causing vision impairments and blindness, reducing quality of life, and generating a great economic challenge. Due to the complexity of the tissue, and the diversity of retinal neurodegenerative diseases in terms of etiology and clinical presentation, so far, there are no cures and only a few early pathological markers have been identified. Increasing efforts have been made to identify and potentiate endogenous protective mechanisms or to abolish detrimental stress responses to preserve retinal structure and function. The discovering of the intracellular monomeric globin neuroglobin (NGB), found at high concentration in the retina, has opened new possibilities for the treatment of retinal disease. Indeed, the NGB capability to reversibly bind oxygen and its neuroprotective function against several types of insults including oxidative stress, ischemia, and neurodegenerative conditions have raised the interest in the possible role of the globin as oxygen supplier in the retina and as a target for retinal neurodegeneration. Here, we provide the undercurrent knowledge on NGB distribution in retinal layers and the evidence about the connection between NGB level modulation and the functional outcome in terms of retinal neuroprotection to provide a novel therapeutic/preventive target for visual pathway degenerative disease.
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Affiliation(s)
- Virginia Solar Fernandez
- Department of Science, University Roma Tre, Viale G. Marconi, 00146 Rome, Italy; (V.S.F.); (M.M.)
- Neuroendocrinology, Metabolism, and Neuropharmacology Unit, IRCCS Santa Lucia Foundation, 00143 Rome, Italy
| | - Maria Marino
- Department of Science, University Roma Tre, Viale G. Marconi, 00146 Rome, Italy; (V.S.F.); (M.M.)
- Neuroendocrinology, Metabolism, and Neuropharmacology Unit, IRCCS Santa Lucia Foundation, 00143 Rome, Italy
| | - Marco Fiocchetti
- Department of Science, University Roma Tre, Viale G. Marconi, 00146 Rome, Italy; (V.S.F.); (M.M.)
- Neuroendocrinology, Metabolism, and Neuropharmacology Unit, IRCCS Santa Lucia Foundation, 00143 Rome, Italy
- Correspondence: ; Tel.: +39-06-5733-6455; Fax: +39-06-5733-6321
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6
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Roberts PA. Mathematical Models of Retinitis Pigmentosa: The Trophic Factor Hypothesis. J Theor Biol 2021; 534:110938. [PMID: 34687673 DOI: 10.1016/j.jtbi.2021.110938] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 10/02/2021] [Accepted: 10/04/2021] [Indexed: 10/20/2022]
Abstract
Retinitis pigmentosa (RP) is the term used to denote a group of inherited retinal-degenerative conditions that cause progressive sight loss. Individuals with this condition lose their light-sensitive photoreceptor cells, known as rods and cones, over a period of years to decades; degeneration starting in the retinal periphery, and spreading peripherally and centrally over time. RP is a rod-cone dystrophy, meaning that rod health and function are affected earlier and more severely than that of cones. Rods degenerate due to an underlying mutation, whereas the reasons for cone degeneration are unknown. A number of mechanisms have been proposed to explain secondary cone loss and the spatio-temporal patterns of retinal degeneration in RP. One of the most promising is the trophic factor hypothesis, which suggests that rods produce a factor necessary for cone survival, such that, when rods degenerate, cone degeneration follows. In this paper we formulate and analyse mathematical models of human RP under the trophic factor hypothesis. These models are constructed as systems of reaction-diffusion partial differential equations in one spatial dimension, and are solved and analysed using a combination of numerical and analytical methods. We predict the conditions under which cones will degenerate following the loss of a patch of rods from the retina, the critical trophic factor treatment rate required to prevent cone degeneration following rod loss and the spatio-temporal patterns of cone loss that would result if the trophic factor mechanism alone were responsible for retinal degeneration.
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Affiliation(s)
- Paul A Roberts
- School of Life Sciences, University of Sussex, John Maynard Smith Building, Brighton BN1 9QG, UK.
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7
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Hif1a and Hif2a can be safely inactivated in cone photoreceptors. Sci Rep 2019; 9:16121. [PMID: 31695081 PMCID: PMC6834587 DOI: 10.1038/s41598-019-52508-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 10/14/2019] [Indexed: 12/30/2022] Open
Abstract
Impaired tissue oxygenation results in hypoxia and leads to the activation of hypoxia-inducible transcription factors (HIF). A chronic, HIF-triggered molecular response to hypoxia may be an important factor in the etiology of age-related macular degeneration (AMD) and is likely activated before any clinical manifestation of the disease. Thus, HIF1 and HIF2 recently emerged as potential therapeutic targets for AMD. To address and evaluate potential consequences of anti-HIF therapies for retinal physiology and function, we generated mouse lines that have Hif1a, or both Hif1a and Hif2a ablated specifically in cone photoreceptors. The knockdown of Hifs in cones did not cause detectable pathological alterations such as loss of cone photoreceptors, retinal degeneration or abnormalities of the retinal vasculature, had no impact on retinal function and resulted in a similar tolerance to hypoxic exposure. Our data indicate that HIF transcription factors are dispensable for maintaining normal cone function and survival in retinas of adult mice. This study provides the groundwork necessary to establish safety profiles for strategies aiming at antagonizing HIF1A and HIF2A function in cone photoreceptors for the treatment of retinal degenerative diseases that involve a hypoxic component such as AMD.
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8
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Wang J, Cai Y, Fu S, Wang W. The effect of the fear factor on the dynamics of a predator-prey model incorporating the prey refuge. CHAOS (WOODBURY, N.Y.) 2019; 29:083109. [PMID: 31472498 DOI: 10.1063/1.5111121] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 07/11/2019] [Indexed: 05/18/2023]
Abstract
In this paper, we investigate the dynamics of an improved Leslie-Gower predator-prey model which is characterized by the reduction of the prey growth rate due to fear of the predator (i.e., antipredator behavior). The value of this study lies in two aspects: mathematically, (i) it provides the existence and the stability of the positive equilibrium; (ii) it gives the existence of the Hopf bifurcation and limit cycle; and (iii) it shows the mechanisms of the fear factor and the prey refuge on the level of the positive equilibrium. Biologically, we find that the influence of the fear factor is complex: (i) increasing the level of fear can cause the level of the population density to decrease and the prey to become extinct; (ii) the effect of the cost of fear on the stability of the positive equilibrium is rich and complex: it can either destabilize the stability and benefit the emergency of the periodic behavior or stabilize the system by excluding the existence of periodic solutions; (iii) with a fixed level of fear, the prey refuge is beneficial to the coexistence of the prey and the predator, and with the increase of the level of the prey refuge, the positive equilibrium may change from stable spiral sink to unstable spiral source to stable spiral sink. These results may enrich the dynamics of the predator-prey systems.
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Affiliation(s)
- Jing Wang
- School of Mathematics Science, Huaiyin Normal University, Huaian 223300, People's Republic of China
| | - Yongli Cai
- School of Mathematics Science, Huaiyin Normal University, Huaian 223300, People's Republic of China
| | - Shengmao Fu
- School of Mathematics and Statistics, Northwest Normal University, Lanzhou 730070, People's Republic of China
| | - Weiming Wang
- School of Mathematics Science, Huaiyin Normal University, Huaian 223300, People's Republic of China
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9
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McHugh KJ, Li D, Wang JC, Kwark L, Loo J, Macha V, Farsiu S, Kim LA, Saint-Geniez M. Computational modeling of retinal hypoxia and photoreceptor degeneration in patients with age-related macular degeneration. PLoS One 2019; 14:e0216215. [PMID: 31185022 PMCID: PMC6559637 DOI: 10.1371/journal.pone.0216215] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 04/16/2019] [Indexed: 12/25/2022] Open
Abstract
Although drusen have long been acknowledged as a primary hallmark of dry age-related macular degeneration (AMD) their role in the disease remains unclear. We hypothesize that drusen accumulation increases the barrier to metabolite transport ultimately resulting in photoreceptor cell death. To investigate this hypothesis, a computational model was developed to evaluate steady-state oxygen distribution in the retina. Optical coherence tomography images from fifteen AMD patients and six control subjects were segmented and translated into 3D in silico representations of retinal morphology. A finite element model was then used to determine the steady-state oxygen distribution throughout the retina for both generic and patient-specific retinal morphology. Oxygen levels were compared to the change in retinal thickness at a later time point to observe possible correlations. The generic finite element model of oxygen concentration in the retina agreed closely with both experimental measurements from literature and clinical observations, including the minimal pathological drusen size identified by AREDS (64 μm). Modeling oxygen distribution in the outer retina of AMD patients showed a substantially stronger correlation between hypoxia and future retinal thinning (Pearson correlation coefficient, r = 0.2162) than between drusen height and retinal thinning (r = 0.0303) indicating the potential value of this physiology-based approach. This study presents proof-of-concept for the potential utility of finite element modeling in evaluating retinal health and also suggests a potential link between transport and AMD pathogenesis. This strategy may prove useful as a prognostic tool for predicting the clinical risk of AMD progression.
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Affiliation(s)
- Kevin J. McHugh
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, MA, United States of America
- Department of Biomedical Engineering, Boston University, Boston, MA, United States of America
| | - Dian Li
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, MA, United States of America
| | - Jay C. Wang
- Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | - Leon Kwark
- Departments of Ophthalmology and Biomedical Engineering, Duke University, Durham, NC, United States of America
| | - Jessica Loo
- Departments of Ophthalmology and Biomedical Engineering, Duke University, Durham, NC, United States of America
| | - Venkata Macha
- Department of Computer Science, Harvard College, Cambridge, MA, United States of America
| | - Sina Farsiu
- Departments of Ophthalmology and Biomedical Engineering, Duke University, Durham, NC, United States of America
| | - Leo A. Kim
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, MA, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
- * E-mail: (LAK); (MSG)
| | - Magali Saint-Geniez
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Boston, MA, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
- * E-mail: (LAK); (MSG)
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10
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Luthert PJ, Serrano L, Kiel C. Opportunities and Challenges of Whole-Cell and -Tissue Simulations of the Outer Retina in Health and Disease. Annu Rev Biomed Data Sci 2018. [DOI: 10.1146/annurev-biodatasci-080917-013356] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Visual processing starts in the outer retina, where photoreceptor cells sense photons that trigger electrical responses. Retinal pigment epithelial cells are located external to the photoreceptor layer and have critical functions in supporting cell and tissue homeostasis and thus sustaining a healthy retina. The high level of specialization makes the retina vulnerable to alterations that promote retinal degeneration. In this review, we discuss opportunities and challenges in proposing whole-cell and -tissue simulations of the human outer retina. An implicit position taken throughout this review is that mapping diverse data sets onto integrative computational models is likely to be a pivotal approach to understanding complex disease and developing novel interventions.
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Affiliation(s)
- Philip J. Luthert
- Institute of Ophthalmology and National Institute for Health Research (NIHR) Biomedical Research Centre, University College London, London EC1V 9EL, United Kingdom
| | - Luis Serrano
- European Molecular Biology Laboratory (EMBL)/Centre for Genomic Regulation (CRG) Systems Biology Research Unit, Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain
| | - Christina Kiel
- European Molecular Biology Laboratory (EMBL)/Centre for Genomic Regulation (CRG) Systems Biology Research Unit, Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain
- Systems Biology Ireland, Charles Institute of Dermatology, and School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland
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11
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Tao Y, Ma Z, Liu B, Fang W, Qin L, Huang YF, Wang L, Gao Y. Hemin supports the survival of photoreceptors injured by N-Methyl-N-nitrosourea: The contributory role of neuroglobin in photoreceptor degeneration. Brain Res 2017; 1678:47-55. [PMID: 29038003 DOI: 10.1016/j.brainres.2017.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 09/12/2017] [Accepted: 10/04/2017] [Indexed: 02/05/2023]
Abstract
Retina is a critical component of the central nerve system that is responsible for the conversion of light stimulus into electrical spikes. Retinitis pigmentosa (RP) comprises a heterogeneous group of inherited retinal dystrophies leading to blindness. We examined retinal neuroglobin (Ngb) expression in a pharmacologically induced RP animal model, the N-Methyl-N-nitrosourea (MNU) administered mice. The retinal Ngb expression in MNU administered mice attenuated following a time dependent manner, suggesting Ngb was involved in the photoreceptor degeneration. Conversely, the intravenous delivery of Hemin, a Ngb up-regulator, enhanced the Ngb expressions in the retinas of MNU administered mice. Optokinetic behavioral tests and Electroretinogram (ERG) examination suggested that the Hemin treatment could improve the visual function of MNU administered mice. The retinal morphology of the Hemin treated group was much more intact than the MNU group as evidenced by retinal sections and optical coherence tomography (OCT) examinations. Moreover, immunostaining experiments showed the cone photoreceptors in the MNU administered mice were also rescued by Hemin treatment. Furthermore, mechanism studies suggested the Hemin treatment not only alleviated the oxidative stress, but also rectified the apoptotic changes in the retinas of MNU administered mice. In conclusion, the intraperitoneally delivery of Hemin can enhance the Ngb expressions in the MNU administered retinas, thereby ameliorating the photoreceptor degeneration and associated visual impairments. These findings would shed light on the opportunity to develop Ngb into a therapeutic molecular against RP.
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Affiliation(s)
- Ye Tao
- Department of Ophthalmology, Key Lab of Ophthalmology and Visual Science, Chinese PLA General Hospital, Beijing 100853, PR China
| | - Zhao Ma
- Department of Neurosurgery, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wu Han, 430014, PR China
| | - Bei Liu
- Department of Neurosurgery and Institute for Functional Brain Disorders, Tangdu Hospital, Fourth Military Medical University, Xi'an 710032, PR China
| | - Wei Fang
- Department of Neurosurgery and Institute for Functional Brain Disorders, Tangdu Hospital, Fourth Military Medical University, Xi'an 710032, PR China
| | - Limin Qin
- Department of Ophthalmology, Key Lab of Ophthalmology and Visual Science, Chinese PLA General Hospital, Beijing 100853, PR China
| | - Yi Fei Huang
- Department of Ophthalmology, Key Lab of Ophthalmology and Visual Science, Chinese PLA General Hospital, Beijing 100853, PR China.
| | - Lu Wang
- Department of Neurosurgery, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wu Han, 430014, PR China.
| | - Yanling Gao
- Department of Human Resource Research Center, 371 Hospital of Chinese PLA, Xinxiang 453000, PR China.
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12
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Linsenmeier RA, Zhang HF. Retinal oxygen: from animals to humans. Prog Retin Eye Res 2017; 58:115-151. [PMID: 28109737 DOI: 10.1016/j.preteyeres.2017.01.003] [Citation(s) in RCA: 148] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 01/13/2017] [Accepted: 01/17/2017] [Indexed: 10/20/2022]
Abstract
This article discusses retinal oxygenation and retinal metabolism by focusing on measurements made with two of the principal methods used to study O2 in the retina: measurements of PO2 with oxygen-sensitive microelectrodes in vivo in animals with a retinal circulation similar to that of humans, and oximetry, which can be used non-invasively in both animals and humans to measure O2 concentration in retinal vessels. Microelectrodes uniquely have high spatial resolution, allowing the mapping of PO2 in detail, and when combined with mathematical models of diffusion and consumption, they provide information about retinal metabolism. Mathematical models, grounded in experiments, can also be used to simulate situations that are not amenable to experimental study. New methods of oximetry, particularly photoacoustic ophthalmoscopy and visible light optical coherence tomography, provide depth-resolved methods that can separate signals from blood vessels and surrounding tissues, and can be combined with blood flow measures to determine metabolic rate. We discuss the effects on retinal oxygenation of illumination, hypoxia and hyperoxia, and describe retinal oxygenation in diabetes, retinal detachment, arterial occlusion, and macular degeneration. We explain how the metabolic measurements obtained from microelectrodes and imaging are different, and how they need to be brought together in the future. Finally, we argue for revisiting the clinical use of hyperoxia in ophthalmology, particularly in retinal arterial occlusions and retinal detachment, based on animal research and diffusion theory.
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Affiliation(s)
- Robert A Linsenmeier
- Biomedical Engineering Department, Northwestern University, 2145 Sheridan Road, Evanston 60208-3107, IL, USA; Neurobiology Department, Northwestern University, 2205 Tech Drive, Evanston 60208-3520, IL, USA; Ophthalmology Department, Northwestern University, 645 N. Michigan Ave, Suite 440, Chicago 60611, IL, USA.
| | - Hao F Zhang
- Biomedical Engineering Department, Northwestern University, 2145 Sheridan Road, Evanston 60208-3107, IL, USA; Ophthalmology Department, Northwestern University, 645 N. Michigan Ave, Suite 440, Chicago 60611, IL, USA.
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13
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Ascenzi P, di Masi A, Leboffe L, Fiocchetti M, Nuzzo MT, Brunori M, Marino M. Neuroglobin: From structure to function in health and disease. Mol Aspects Med 2016; 52:1-48. [DOI: 10.1016/j.mam.2016.10.004] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 10/27/2016] [Accepted: 10/27/2016] [Indexed: 01/01/2023]
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14
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Guidolin D, Tortorella C, Marcoli M, Maura G, Agnati LF. Neuroglobin, a Factor Playing for Nerve Cell Survival. Int J Mol Sci 2016; 17:ijms17111817. [PMID: 27809238 PMCID: PMC5133818 DOI: 10.3390/ijms17111817] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 10/14/2016] [Accepted: 10/26/2016] [Indexed: 12/17/2022] Open
Abstract
Cell death represents the final outcome of several pathological conditions of the central nervous system and available evidence suggests that in both acute injuries and neurodegenerative diseases it is often associated with mitochondrial dysfunction. Thus, the possibility to prevent mitochondrial events involved in cell death might represent efficient tools to limit neuronal damage. In recent years, increased attention has been paid to the endogenous protein neuroglobin, since accumulating evidence showed that its high expression was associated with preserved mitochondrial function and to an increased survival of nerve cells in vitro and in vivo in a variety of experimental models of cell insult. The biological and structural features of neuroglobin and the mitochondria-related mechanisms of neuroglobin-induced neuroprotection will be here briefly discussed. In this respect, the inhibition of the intrinsic pathway of apoptosis emerges as a key neuroprotective effect induced by the protein. These findings could open the possibility to develop efficient neuroglobin-mediated therapeutic strategies aimed at minimizing the neuronal cell death occurring in impacting neurological pathologies like stroke and neurodegenerative diseases.
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Affiliation(s)
- Diego Guidolin
- Department of Neuroscience, University of Padova, Padova 35122, Italy.
| | - Cinzia Tortorella
- Department of Neuroscience, University of Padova, Padova 35122, Italy.
| | - Manuela Marcoli
- Department of Pharmacy and Center of Excellence for Biomedical Research, University of Genova, Genova 16126, Italy.
| | - Guido Maura
- Department of Pharmacy and Center of Excellence for Biomedical Research, University of Genova, Genova 16126, Italy.
| | - Luigi F Agnati
- Department of Biomedical Sciences, University of Modena and Reggio Emilia, Modena 41121, Italy.
- Department of Neuroscience, Karolinska Institutet, Stockholm 17177, Sweden.
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He Y, Trumbore SE, Torn MS, Harden JW, Vaughn LJS, Allison SD, Randerson JT. Radiocarbon constraints imply reduced carbon uptake by soils during the 21st century. Science 2016; 353:1419-1424. [DOI: 10.1126/science.aad4273] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 08/29/2016] [Indexed: 11/02/2022]
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