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Marte ME, Kurokawa K, Jung H, Liu Y, Bernucci MT, King BJ, Miller DT. Characterizing Presumed Displaced Retinal Ganglion Cells in the Living Human Retina of Healthy and Glaucomatous Eyes. Invest Ophthalmol Vis Sci 2024; 65:20. [PMID: 39259176 PMCID: PMC11401130 DOI: 10.1167/iovs.65.11.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2024] Open
Abstract
Purpose The purpose of this study was to investigate the large somas presumed to be displaced retinal ganglion cells (dRGCs) located in the inner nuclear layer (INL) of the living human retina. Whereas dRGCs have previously been studied in mammals and human donor tissue, they have never been investigated in the living human retina. Methods Five young, healthy subjects and three subjects with varying types of glaucoma were imaged at multiple locations in the macula using adaptive optics optical coherence tomography. In the acquired volumes, bright large somas at the INL border with the inner plexiform layer were identified, and the morphometric biomarkers of soma density, en face diameter, and spatial distribution were measured at up to 13 degrees retinal eccentricity. Susceptibility to glaucoma was assessed. Results In the young, healthy individuals, mean density of the bright, large somas was greatest foveally (550 and 543 cells/mm2 at 2 degrees temporal and nasal, respectively) and decreased with increasing retinal eccentricity (38 cells/mm2 at 13 degrees temporal, the farthest we measured). Soma size distribution showed the opposite trend with diameters and size variation increasing with retinal eccentricity, from 12.7 ± 1.8 µm at 2 degrees to 15.7 ± 3.5 µm at 13 degrees temporal, and showed evidence of a bimodal distribution in more peripheral locations. Within and adjacent to the arcuate defects of the subjects with glaucoma, density of the bright large somas was significantly lower than found in the young, healthy individuals. Conclusions Our results suggest that the bright, large somas at the INL border are likely comprised of dRGCs but amacrine cells may contribute too. These somas appear highly susceptible to glaucomatous damage.
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Affiliation(s)
- Mary E Marte
- Indiana University School of Optometry, Bloomington, Indiana, United States
| | - Kazuhiro Kurokawa
- Indiana University School of Optometry, Bloomington, Indiana, United States
| | - HaeWon Jung
- Indiana University School of Optometry, Bloomington, Indiana, United States
| | - Yan Liu
- Indiana University School of Optometry, Bloomington, Indiana, United States
| | - Marcel T Bernucci
- Indiana University School of Optometry, Bloomington, Indiana, United States
| | - Brett J King
- Indiana University School of Optometry, Bloomington, Indiana, United States
| | - Donald T Miller
- Indiana University School of Optometry, Bloomington, Indiana, United States
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2
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Jiang Z, Chernoff D, Galenchik-Chan A, Tomorri D, Honkanen RA, Duong TQ, Muir ER. Improved MRI methods to quantify retinal and choroidal blood flow applied to a model of glaucoma. FRONTIERS IN OPHTHALMOLOGY 2024; 4:1385495. [PMID: 38984144 PMCID: PMC11182105 DOI: 10.3389/fopht.2024.1385495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 04/23/2024] [Indexed: 07/11/2024]
Abstract
Purpose Blood flow (BF) of the retinal and choroidal vasculatures can be quantitatively imaged using MRI. This study sought to improve methods of data acquisition and analysis for MRI of layer-specific retinal and choroidal BF and then applied this approach to detect reduced ocular BF in a well-established mouse model of glaucoma from both eyes. Methods Quantitative BF magnetic resonance imaging (MRI) was performed on glaucomatous DBA/2J and normal C57BL/6J mice. Arterial spin labeling MRI was applied to image retinal and choroidal BF using custom-made dual eye coils that could image both eyes during the same scan. Statistics using data from a single eye or two eyes were compared. BF values were calculated using two approaches. The BF rate per quantity of tissue was calculated as commonly done, and the peak BF values of the retinal and choroidal vasculatures were taken. Additionally, the BF rate per retinal surface area was calculated using a new analysis approach to attempt to reduce partial volume and variability by integrating BF over the retinal and choroidal depths. Results Ocular BF of both eyes could be imaged using the dual coil setup without effecting scan time. Intraocular pressure was significantly elevated in DBA/2J mice compared to C57BL/6J mice (P<0.01). Both retinal and choroidal BF were significantly decreased in DBA/2J mice in comparison to the age-matched normal C57BL/6J mice across all measurements (P < 0.01). From simulations, the values from the integrated BF analysis method had less partial volume effect, and from in vivo scans, this analysis approach also improved power. Conclusion The dual eye coil setup allows bilateral eye data acquisition, increasing the amount of data acquired without increasing acquisition times in vivo. The reduced ocular BF found using the improved acquisition and analysis approaches replicated the results of previous studies on DBA/2J mice. The ocular hypertensive stress-induced BF reduction found within these mice may represent changes associated with glaucomatous progression.
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Affiliation(s)
- Zhao Jiang
- Department of Radiology, Stony Brook University, Stony Brook, NY, United States
| | - Diane Chernoff
- Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - Andre Galenchik-Chan
- Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - David Tomorri
- School of Health Professions, Stony Brook University, Stony Brook, NY, United States
| | - Robert A. Honkanen
- Department of Ophthalmology, Stony Brook University, Stony Brook, NY, United States
| | - Timothy Q. Duong
- Department of Radiology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Eric R. Muir
- Department of Radiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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3
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Pang JJ. The Variety of Mechanosensitive Ion Channels in Retinal Neurons. Int J Mol Sci 2024; 25:4877. [PMID: 38732096 PMCID: PMC11084373 DOI: 10.3390/ijms25094877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 04/16/2024] [Accepted: 04/20/2024] [Indexed: 05/13/2024] Open
Abstract
Alterations in intraocular and external pressure critically involve the pathogenesis of glaucoma, traumatic retinal injury (TRI), and other retinal disorders, and retinal neurons have been reported to express multiple mechanical-sensitive channels (MSCs) in recent decades. However, the role of MSCs in visual functions and pressure-related retinal conditions has been unclear. This review will focus on the variety and functional significance of the MSCs permeable to K+, Na+, and Ca2+, primarily including the big potassium channel (BK); the two-pore domain potassium channels TRAAK and TREK; Piezo; the epithelial sodium channel (ENaC); and the transient receptor potential channels vanilloid TRPV1, TRPV2, and TRPV4 in retinal photoreceptors, bipolar cells, horizontal cells, amacrine cells, and ganglion cells. Most MSCs do not directly mediate visual signals in vertebrate retinas. On the other hand, some studies have shown that MSCs can open in physiological conditions and regulate the activities of retinal neurons. While these data reasonably predict the crossing of visual and mechanical signals, how retinal light pathways deal with endogenous and exogenous mechanical stimulation is uncertain.
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Affiliation(s)
- Ji-Jie Pang
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
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4
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Donen G, Milad N, Bernatchez P. Humanization of the mdx Mouse Phenotype for Duchenne Muscular Dystrophy Modeling: A Metabolic Perspective. J Neuromuscul Dis 2023; 10:1003-1012. [PMID: 37574742 PMCID: PMC10657711 DOI: 10.3233/jnd-230126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2023] [Indexed: 08/15/2023]
Abstract
Duchenne muscular dystrophy (DMD) is a severe form of muscular dystrophy (MD) that is characterized by early muscle wasting and lethal cardiorespiratory failure. While the mdx mouse is the most common model of DMD, it fails to replicate the severe loss of muscle mass and other complications observed in patients, in part due to the multiple rescue pathways found in mice. This led to several attempts at improving DMD animal models by interfering with these rescue pathways through double transgenic approaches, resulting in more severe phenotypes with mixed relevance to the human pathology. As a growing body of literature depicts DMD as a multi-system metabolic disease, improvements in mdx-based modeling of DMD may be achieved by modulating whole-body metabolism instead of muscle homeostasis. This review provides an overview of the established dual-transgenic approaches that exacerbate the mild mdx phenotype by primarily interfering with muscle homeostasis and highlights how advances in DMD modeling coincide with inducing whole-body metabolic changes. We focus on the DBA2/J strain-based D2.mdx mouse with heightened transforming growth factor (TGF)-β signaling and the dyslipidemic mdx/apolipoprotein E (mdx/ApoE) knock-out (KO) mouse, and summarize how these novel models emulate the metabolic changes observed in DMD.
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Affiliation(s)
| | | | - Pascal Bernatchez
- Correspondence to: Dr. Pascal Bernatchez, Department of Anesthesiology, Pharmacology & Therapeutics, University of British Columbia, 2176 Health Sciences mall, room 217, Vancouver BC, V6T 1Z3, Canada. Tel.: +1 604 806 8346 /Ext.66060; E-mail:
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5
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Cáceres-Vélez PR, Hui F, Hercus J, Bui B, Jusuf PR. Restoring the oxidative balance in age-related diseases - An approach in glaucoma. Ageing Res Rev 2022; 75:101572. [PMID: 35065274 DOI: 10.1016/j.arr.2022.101572] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 12/10/2021] [Accepted: 01/18/2022] [Indexed: 02/07/2023]
Abstract
As human life expectancy increases, age-related health issues including neurodegenerative diseases continue to rise. Regardless of genetic or environmental factors, many neurodegenerative conditions share common pathological mechanisms, such as oxidative stress, a hallmark of many age-related health burdens. In this review, we describe oxidative damage and mitochondrial dysfunction in glaucoma, an age-related neurodegenerative eye disease affecting 80 million people worldwide. We consider therapeutic approaches used to counteract oxidative stress in glaucoma, including untapped treatment options such as novel plant-derived antioxidant compounds that can reduce oxidative stress and prevent neuronal loss. We summarize the current pre-clinical models and clinical work exploring the therapeutic potential of a range of candidate plant-derived antioxidant compounds. Finally, we explore advances in drug delivery systems, particular those employing nanotechnology-based carriers which hold significant promise as a carrier for antioxidants to treat age-related disease, thus reviewing the key current state of all of the aspects required towards translation.
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6
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Bierlein ER, Smith JC, Van Hook MJ. Mechanism for altered dark-adapted electroretinogram responses in DBA/2J mice includes pupil dilation deficits. Curr Eye Res 2022; 47:897-907. [PMID: 35179406 DOI: 10.1080/02713683.2022.2044055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
PURPOSE The DBA/2J (D2) mouse is an established model of pigmentary glaucoma, a type of primary open angle glaucoma. Prior studies have documented defects in flash electroretinogram (ERG) responses in D2 mice, but the origin of those defects is not clear. The purpose of this study was to understand the origin of these A-wave and B-wave changes in D2 ERGs.Materials & Methods: To accomplish this, we analyzed the differences between 9-month-old DBA/2J-Gpnmb+ (D2-control) and D2 mouse eyes in relation to ERG responses, intraocular pressure (IOP), outer nuclear layer thickness, and pupil area. RESULTS D2 scotopic ERGs showed lower A-wave amplitude and longer implicit time as well as a significant rightward shift in the intensity-response curve. D2 IOP increased at approximately seven months of age and had a weak correlation with the ERG A-wave sensitivity. Outer nuclear layer thickness was not significantly different in D2s compared to D2-control retinas. D2 mouse pupils also showed abnormal pupillary shape and no dilation following treatment with tropicamide eye drops. The pupil size moderately correlated with the A-wave sensitivity and this was pharmacologically replicated in C57Bl/6J mice following administration of pilocarpine to constrict the pupils. However, pilocarpine treatment did not affect ERG amplitudes. CONCLUSIONS These data suggest that the smaller pupil sizes prevented light from reaching the photoreceptors and thus contributed to reduced ERG sensitivity in D2 mice. The reduced ERG A-wave amplitude in D2 mice likely results from dysfunctional photoreceptor responses.
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Affiliation(s)
- Elizabeth R Bierlein
- Truhlsen Eye Institute, Department of Ophthalmology & Visual Sciences, University of Nebraska Medical Center, Omaha, NE, USA.,Department of Pharmacology & Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA
| | - Jennie C Smith
- Truhlsen Eye Institute, Department of Ophthalmology & Visual Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - Matthew J Van Hook
- Truhlsen Eye Institute, Department of Ophthalmology & Visual Sciences, University of Nebraska Medical Center, Omaha, NE, USA.,Department of Cellular & Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
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Loizzo S, Rimondini R, Campana G, Fortuna A, Maroccia Z, Martorana A, Koch G. C57BL/6J and DBA/2J strains present opposite sex differences in flash visual evoked potential latency: A possible confusing factor in gender studies on neurological diseases' transgenic models. Brain Res Bull 2021; 176:18-24. [PMID: 34391824 DOI: 10.1016/j.brainresbull.2021.08.005] [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: 05/07/2021] [Revised: 08/09/2021] [Accepted: 08/10/2021] [Indexed: 10/20/2022]
Abstract
The cholinergic neurotransmitter system in the brain is crucial in processing information related to cognitive, behavioral, and motor functions. A cholinergic dysfunction has been correctly described as one of the primary causes of neurodegenerative diseases. Differences in levels of acetylcholine or expression and function of receptors in selected brain areas have been indicated as one of the causes of sexual dimorphism in neurotransmission. However, variability in results among studies based on different mice strains could affect conclusions on this topic. Visual evoked potentials (VEPs) of male and female DBA/2J and C57BL/6J mice, which are two of the most common strains backgrounds in use for developing transgenic mice models of neurological diseases, have been studied. Effects induced by a single low dose of physostigmine have also been performed to evaluate the cholinergic system involvement. VEPs responses to luminous stimuli in C57BL/6J mice have shown a consistently lower latency than in DBA/2J, confirming the previous observation of strain differences in cholinergic function. Interestingly, strains present an opposite-sex difference in VEP latency not apparently related to sensitivity to physostigmine. These findings point at paying extreme attention to the choice of the genetic background of the animal model, especially in those basic and pre-clinical experiments that involve visual functioning.
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Affiliation(s)
- Stefano Loizzo
- Department of Cardiovascular, Endocrine-Metabolic and Ageing-Associated Diseases, Istituto Superiore di Sanità, Rome, Italy.
| | - Roberto Rimondini
- Department of Medical and Clinical Sciences, University of Bologna, Bologna, Italy
| | - Gabriele Campana
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Andrea Fortuna
- Department of Cardiovascular, Endocrine-Metabolic and Ageing-Associated Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Zaira Maroccia
- Department of Cardiovascular, Endocrine-Metabolic and Ageing-Associated Diseases, Istituto Superiore di Sanità, Rome, Italy
| | | | - Giacomo Koch
- Non-Invasive Brain Stimulation Unit, Department of Behavioral and Clinical Neurology, Santa Lucia Foundation, Rome, Italy
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8
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Pang JJ, Wu SM. Ocular Pressure-Volume Relationship and Ganglion Cell Death in Glaucoma. OBM NEUROBIOLOGY 2021; 5:10.21926/obm.neurobiol.2102098. [PMID: 34308265 PMCID: PMC8297795 DOI: 10.21926/obm.neurobiol.2102098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We studied how GC death in glaucoma related to the intraocular pressure (IOP), eyeball volume (VS) and elasticity (volumetric KS and tensile ES), and eyeball volume-pressure relation. Glaucomatous GC loss was studied in DBA/2J (D2) mice with wild-type mice as controls. GCs were retrogradely identified and observed with a confocal microscope. The elasticity calculation was also done on published data from patients treated by a gas bubble injection in the vitreous cavity. The GC population in D2 mice (1.5- to 14-month-old) was negatively correlated with following factors: VS (p = 0.0003), age (p = 0.0026) and IOP (but p = 0.0966). As indicated by average values, adult D2 mice (≥6 months) suffered significant GC loss, low KS and ES, and universal expansion of VS with normal IOP. KS and ES in the patients were also lower upon prolonged eyeball expansion compared to acute expansion. Based on the results and presumptions of a closed and continuous eyeball space (thereby ΔVS ≈ ΔVW, ΔVW-the change in the aqueous humor amount), we deduced equations on the ocular volume-pressure relationship: ΔIOP = KS*ΔVW/VS or ΔIOP = (2/3)*[1/(1-ν)]*(H/R)*ES*ΔVW/VS (ν, Poisson's ratio taken as 0.5; R, the curvature radius; and H, the shell thickness). Under normal atmospheric pressure, IOP of 10~50 mmHg contributed only 1.2~6.6% of the pressure opposing the retina and eyeball shell. We conclude: 1) A disturbance of ocular volume-pressure homeostasis, mediated primarily by low KS and ES, expanded VS, and large ΔVW, is correlated with GC death in glaucoma and 2) D2 mice with GC loss and normal IOP may serve as animal models for human normal-tension glaucoma.
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Affiliation(s)
- Ji-Jie Pang
- Department of Ophthalmology, Baylor College of Medicine, One Baylor
Plaza, NC 205, Houston, Texas
| | - Samuel M. Wu
- Department of Ophthalmology, Baylor College of Medicine, One Baylor
Plaza, NC 205, Houston, Texas
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9
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Activation of Apoptosis in a βB1-CTGF Transgenic Mouse Model. Int J Mol Sci 2021; 22:ijms22041997. [PMID: 33671472 PMCID: PMC7922353 DOI: 10.3390/ijms22041997] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 02/09/2021] [Accepted: 02/12/2021] [Indexed: 11/23/2022] Open
Abstract
To reveal the pathomechanisms of glaucoma, a common cause of blindness, suitable animal models are needed. As previously shown, retinal ganglion cell and optic nerve degeneration occur in βB1-CTGF mice. Here, we aimed to determine possible apoptotic mechanisms and degeneration of different retinal cells. Hence, retinae were processed for immunohistology (n = 5–9/group) and quantitative real-time PCR analysis (n = 5–7/group) in 5- and 10-week-old βB1-CTGF and wildtype controls. We noted significantly more cleaved caspase 3+ cells in βB1-CTGF retinae at 5 (p = 0.005) and 10 weeks (p = 0.02), and a significant upregulation of Casp3 and Bax/Bcl2 mRNA levels (p < 0.05). Furthermore, more terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL+) cells were detected in transgenic mice at 5 (p = 0.03) and 10 weeks (p = 0.02). Neurofilament H staining (p = 0.01) as well as Nefh (p = 0.02) and Tubb3 (p = 0.009) mRNA levels were significantly decreased at 10 weeks. GABAergic synapse intensity was lower at 5 weeks, while no alterations were noted at 10 weeks. The glutamatergic synapse intensity was decreased at 5 (p = 0.007) and 10 weeks (p = 0.01). No changes were observed for bipolar cells, photoreceptors, and macroglia. We conclude that apoptotic processes and synapse loss precede neuronal death in this model. This slow progression rate makes the βB1-CTGF mice a suitable model to study primary open-angle glaucoma.
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10
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Tam WY, Cheung KK. Phenotypic characteristics of commonly used inbred mouse strains. J Mol Med (Berl) 2020; 98:1215-1234. [PMID: 32712726 DOI: 10.1007/s00109-020-01953-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 07/13/2020] [Accepted: 07/16/2020] [Indexed: 12/16/2022]
Abstract
The laboratory mouse is the most commonly used mammalian model for biomedical research. An enormous number of mouse models, such as gene knockout, knockin, and overexpression transgenic mice, have been created over the years. A common practice to maintain a genetically modified mouse line is backcrossing with standard inbred mice over several generations. However, the choice of inbred mouse for backcrossing is critical to phenotypic characterization because phenotypic variabilities are often observed between mice with different genetic backgrounds. In this review, the major features of commonly used inbred mouse lines are discussed. The aim is to provide information for appropriate selection of inbred mouse lines for genetic and behavioral studies.
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Affiliation(s)
- Wing Yip Tam
- University Research Facility in Behavioral and Systems Neuroscience, The Hong Kong Polytechnic University, Hong Kong, SAR, China
| | - Kwok-Kuen Cheung
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong, SAR, China.
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11
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Guttenplan KA, Stafford BK, El-Danaf RN, Adler DI, Münch AE, Weigel MK, Huberman AD, Liddelow SA. Neurotoxic Reactive Astrocytes Drive Neuronal Death after Retinal Injury. Cell Rep 2020; 31:107776. [PMID: 32579912 PMCID: PMC8091906 DOI: 10.1016/j.celrep.2020.107776] [Citation(s) in RCA: 141] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 03/30/2020] [Accepted: 05/26/2020] [Indexed: 01/16/2023] Open
Abstract
Glaucoma is a neurodegenerative disease that features the death of retinal ganglion cells (RGCs) in the retina, often as a result of prolonged increases in intraocular pressure. We show that preventing the formation of neuroinflammatory reactive astrocytes prevents the death of RGCs normally seen in a mouse model of glaucoma. Furthermore, we show that these spared RGCs are electrophysiologically functional and thus still have potential value for the function and regeneration of the retina. Finally, we demonstrate that the death of RGCs depends on a combination of both an injury to the neurons and the presence of reactive astrocytes, suggesting a model that may explain why reactive astrocytes are toxic only in some circumstances. Altogether, these findings highlight reactive astrocytes as drivers of RGC death in a chronic neurodegenerative disease of the eye.
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Affiliation(s)
- Kevin A Guttenplan
- Department of Neurobiology, Stanford University, Stanford, CA 94305, USA.
| | | | - Rana N El-Danaf
- Department of Neurobiology, Stanford University, Stanford, CA 94305, USA; Center for Genomics and Systems Biology, NYU Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Drew I Adler
- Neuroscience Institute, NYU School of Medicine, New York, NY 10016, USA
| | - Alexandra E Münch
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA
| | - Maya K Weigel
- Department of Neurobiology, Stanford University, Stanford, CA 94305, USA
| | - Andrew D Huberman
- Department of Neurobiology, Stanford University, Stanford, CA 94305, USA; Department of Ophthalmology, Stanford University, Stanford, CA 94305, USA
| | - Shane A Liddelow
- Neuroscience Institute, NYU School of Medicine, New York, NY 10016, USA; Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY 10016, USA; Department of Ophthalmology, NYU School of Medicine, New York, NY 10016, USA.
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12
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Destructive Effect of Intravitreal Heat Shock Protein 27 Application on Retinal Ganglion Cells and Neurofilament. Int J Mol Sci 2020; 21:ijms21020549. [PMID: 31952234 PMCID: PMC7014083 DOI: 10.3390/ijms21020549] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/09/2020] [Accepted: 01/09/2020] [Indexed: 01/01/2023] Open
Abstract
Heat shock protein 27 (HSP27) is commonly involved in cellular stress. Increased levels of HSP27 as well as autoantibodies against this protein were previously detected in glaucoma patients. Moreover, systemic immunization with HSP27 induced glaucoma-like damage in rodents. Now, for the first time, the direct effects of an intravitreal HSP27 application were investigated. For this reason, HSP27 or phosphate buffered saline (PBS, controls) was applied intravitreally in rats (n = 12/group). The intraocular pressure (IOP) as well as the electroretinogram recordings were comparable in HSP27 and control eyes 21 days after the injection. However, significantly fewer retinal ganglion cells (RGCs) and amacrine cells were observed in the HSP27 group via immunohistochemistry and western blot analysis. The number of bipolar cells, on the other hand, was similar in both groups. Interestingly, a stronger neurofilament degeneration was observed in HSP27 optic nerves, while no differences were noted regarding the myelination state. In summary, intravitreal HSP27 injection led to an IOP-independent glaucoma-like damage. A degeneration of RGCs as well as their axons and amacrine cells was noted. This suggests that high levels of extracellular HSP27 could have a direct damaging effect on RGCs.
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Moghimi S, Fatehi N, Nguyen AH, Romero P, Caprioli J, Nouri-Mahdavi K. Relationship of the Macular Ganglion Cell and Inner Plexiform Layers in Healthy and Glaucoma Eyes. Transl Vis Sci Technol 2019; 8:27. [PMID: 31637107 PMCID: PMC6798328 DOI: 10.1167/tvst.8.5.27] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 08/02/2019] [Indexed: 01/10/2023] Open
Abstract
Purpose To explore factors influencing the inner plexiform layer (IPL) in healthy subjects and to test the hypothesis that IPL thickness is preferentially decreased in glaucoma as compared with ganglion cell layer (GCL) thickness. Methods Ninety-nine glaucomatous eyes and 66 healthy eyes (165 subjects) underwent macular spectral-domain optical coherence tomography (SD-OCT) imaging and GCL and IPL were segmented creating 8 × 8 arrays of 3° × 3° superpixels. The central 24 superpixels were categorized into three levels of eccentricity (∼1.5°, 4.5°, and 7.5° from the foveal center). Linear mixed models were used to determine predictive parameters for IPL thickness in healthy subjects and to explore the influence of diagnosis of glaucoma on IPL thickness taking into account the effect of GCL thickness and other covariates. Results Being located at 4.5° eccentricity predicted thicker IPL compared with 1.5° eccentricity (P < 0.001) in multivariable models in healthy subjects, whereas older age (P = 0.001) and Asian ethnicity (P = 0.021) were associated with thinner IPL. Diagnosis of glaucoma was not associated with thinner IPL regardless of eccentricity after accounting for age and ethnicity. The results were similar when only eyes with mean deviation greater than –6 dB were analyzed. Conclusions Ethnicity and distance from the fovea are the main determinants of IPL thickness in the central macula. Preferential thinning of the macular IPL, compared with GCL, could not be detected in this study regardless of glaucoma stage. Translational Relevance There is no evidence for preferential thinning of the macular IPL in glaucoma compared with GCL based on currently available SD-OCT–imaging technology.
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Affiliation(s)
- Sasan Moghimi
- Glaucoma Division, Stein Eye Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA.,Hamilton Glaucoma Center, Shiley Eye Institute, University of California San Diego, San Diego, CA, USA
| | - Nima Fatehi
- Glaucoma Division, Stein Eye Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Andrew H Nguyen
- Glaucoma Division, Stein Eye Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Pablo Romero
- Glaucoma Division, Stein Eye Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Joseph Caprioli
- Glaucoma Division, Stein Eye Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Kouros Nouri-Mahdavi
- Glaucoma Division, Stein Eye Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
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Faiq MA, Wollstein G, Schuman JS, Chan KC. Cholinergic nervous system and glaucoma: From basic science to clinical applications. Prog Retin Eye Res 2019; 72:100767. [PMID: 31242454 PMCID: PMC6739176 DOI: 10.1016/j.preteyeres.2019.06.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 06/19/2019] [Accepted: 06/21/2019] [Indexed: 02/08/2023]
Abstract
The cholinergic system has a crucial role to play in visual function. Although cholinergic drugs have been a focus of attention as glaucoma medications for reducing eye pressure, little is known about the potential modality for neuronal survival and/or enhancement in visual impairments. Citicoline, a naturally occurring compound and FDA approved dietary supplement, is a nootropic agent that is recently demonstrated to be effective in ameliorating ischemic stroke, traumatic brain injury, Parkinson's disease, Alzheimer's disease, cerebrovascular diseases, memory disorders and attention-deficit/hyperactivity disorder in both humans and animal models. The mechanisms of its action appear to be multifarious including (i) preservation of cardiolipin, sphingomyelin, and arachidonic acid contents of phosphatidylcholine and phosphatidylethanolamine, (ii) restoration of phosphatidylcholine, (iii) stimulation of glutathione synthesis, (iv) lowering glutamate concentrations and preventing glutamate excitotoxicity, (v) rescuing mitochondrial function thereby preventing oxidative damage and onset of neuronal apoptosis, (vi) synthesis of myelin leading to improvement in neuronal membrane integrity, (vii) improving acetylcholine synthesis and thereby reducing the effects of mental stress and (viii) preventing endothelial dysfunction. Such effects have vouched for citicoline as a neuroprotective, neurorestorative and neuroregenerative agent. Retinal ganglion cells are neurons with long myelinated axons which provide a strong rationale for citicoline use in visual pathway disorders. Since glaucoma is a form of neurodegeneration involving retinal ganglion cells, citicoline may help ameliorate glaucomatous damages in multiple facets. Additionally, trans-synaptic degeneration has been identified in humans and experimental models of glaucoma suggesting the cholinergic system as a new brain target for glaucoma management and therapy.
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Affiliation(s)
- Muneeb A Faiq
- Department of Ophthalmology, New York University (NYU) School of Medicine, NYU Langone Health, New York, NY, United States
| | - Gadi Wollstein
- Department of Ophthalmology, New York University (NYU) School of Medicine, NYU Langone Health, New York, NY, United States
| | - Joel S Schuman
- Department of Ophthalmology, New York University (NYU) School of Medicine, NYU Langone Health, New York, NY, United States
| | - Kevin C Chan
- Department of Ophthalmology, New York University (NYU) School of Medicine, NYU Langone Health, New York, NY, United States; Department of Radiology, New York University (NYU) School of Medicine, NYU Langone Health, New York, NY, United States; Center for Neural Science, Faculty of Arts and Science, New York University, New York, NY, United States.
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15
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Zhou L, Chen W, Lin D, Hu W, Tang Z. Neuronal apoptosis, axon damage and synapse loss occur synchronously in acute ocular hypertension. Exp Eye Res 2019; 180:77-85. [DOI: 10.1016/j.exer.2018.12.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 12/01/2018] [Accepted: 12/14/2018] [Indexed: 10/27/2022]
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16
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Nitezki T, Schulz N, Krämer S. Color matters: They would choose if they could (see)! Lab Anim 2018; 52:611-620. [DOI: 10.1177/0023677218766370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Concerning standardization of laboratory animal husbandry, only exiguous changes of habitat can potentially influence animal physiology or results of behavioral tests. Routinely, mice chow is dyed when different types of diets are dispensed. Given the fact that the dye itself has no effects on food odor or flavor, we wanted to test the hypothesis that the color of chow has an impact on food uptake in mice. Twelve-week-old male mice of different strains (C57BL/6J, DBA/2J, C3H/HeJ, BALB/cJ; n = 12/strain) were single-housed in PhenoMaster® cages. After acclimatization standard mice chow in different colors was administered. Food intake was monitored as a two-alternative choice test of different color combinations. All animals had an average food intake of 3 g/d and no preferences were observed when a combination of identically colored food was offered. Preference tests yielded significant aversion to blue food and significant attraction to yellow and green food in C57BL/6 and DBA/2J mice. In C3H/HeJ and BALB/cJ mice no color-related pattern occurred. Selected mice strains have known differences concerning functionality of their visual sense. C57BL/6 and DBA/2 mice are considered to be normal sighted at testing age, BALB/c is representative for albino strains and C3H mice carry mutations resulting in retinal alterations. Results suggesting that normal-sighted mice would be selective concerning food color when given the choice. Nevertheless, this does not influence overall quantity of food intake when animals were provided solely with food colored with a single dye. Moreover, visually impaired mice showed no color-related food preferences.
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Affiliation(s)
- Tina Nitezki
- Department of Toxicology, Institute of Nutritional Science, University of Potsdam, Germany
| | | | - Stephanie Krämer
- Department of Toxicology, Institute of Nutritional Science, University of Potsdam, Germany
- Department of Laboratory Animal Science and Animal Welfare, Justus-Liebig University Giessen, Germany
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Axogenic mechanism enhances retinal ganglion cell excitability during early progression in glaucoma. Proc Natl Acad Sci U S A 2018; 115:E2393-E2402. [PMID: 29463759 PMCID: PMC5877940 DOI: 10.1073/pnas.1714888115] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Identifying new therapies for neurodegenerative disease requires understanding how neurons respond to stress and whether this response includes adaptation to slow progression. Because neurodegeneration affects both axons and dendrites, with their synaptic contacts, adaptation could involve both compartments. We investigated this question in experimental glaucoma, the world’s leading cause of irreversible vision loss. Glaucoma attacks retinal ganglion cell neurons and their axons, which comprise the optic nerve. We found that elevations in ocular pressure, a prominent risk factor for glaucoma, caused a paradoxical increase in ganglion cell excitability, including response to light, even in cells with substantial dendritic pruning. This adaptation arose from voltage-dependent mechanisms in the axon and may help maintain signaling to the brain to preserve vision. Diseases of the brain involve early axon dysfunction that often precedes outright degeneration. Pruning of dendrites and their synapses represents a potential driver of axonopathy by reducing activity. Optic nerve degeneration in glaucoma, the world’s leading cause of irreversible blindness, involves early stress to retinal ganglion cell (RGC) axons from sensitivity to intraocular pressure (IOP). This sensitivity also influences survival of RGC dendrites and excitatory synapses in the retina. Here we tested in individual RGCs identified by type the relationship between dendritic organization and axon signaling to light following modest, short-term elevations in pressure. We found dendritic pruning occurred early, by 2 wk of elevation, and independent of whether the RGC responded to light onset (ON cells) or offset (OFF cells). Pruning was similarly independent of ON and OFF in the DBA/2J mouse, a chronic glaucoma model. Paradoxically, all RGCs, even those with significant pruning, demonstrated a transient increase in axon firing in response to the preferred light stimulus that occurred on a backdrop of generally enhanced excitability. The increased response was not through conventional presynaptic signaling, but rather depended on voltage-sensitive sodium channels that increased transiently in the axon. Pruning, axon dysfunction, and deficits in visual acuity did not progress between 2 and 4 wk of elevation. These results suggest neurodegeneration in glaucoma involves an early axogenic response that counters IOP-related stress to excitatory dendritic architecture to slow progression and maintain signaling to the brain. Thus, short-term exposure to elevated IOP may precondition the neural system to further insult.
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Reinehr S, Kuehn S, Casola C, Koch D, Stute G, Grotegut P, Dick HB, Joachim SC. HSP27 immunization reinforces AII amacrine cell and synapse damage induced by S100 in an autoimmune glaucoma model. Cell Tissue Res 2017; 371:237-249. [PMID: 29064077 DOI: 10.1007/s00441-017-2710-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 10/11/2017] [Indexed: 12/11/2022]
Abstract
Previous studies have revealed a loss of retinal ganglion cells (RGCs) and optic nerve fibers after immunization with the S100B protein. Addition of heat shock protein 27 (HSP27) also leads to a decrease of RGCs. Our present aim has been to analyze various retinal cell types after immunization with S100B or S100B + HSP27 (S100 + HSP). After 28 days, retinas were processed for immunohistology and Western blot. RGCs, immunostained for NeuN, were significantly decreased in the S100 and the S100 + HSP groups. Significantly fewer ChAT+ cells were noted in both groups, whereas parvalbumin+ cells were only affected in the S100 + HSP group. Western blot results also revealed fewer ChAT signals in both immunized groups. No changes were noted with regard to PKCα+ rod bipolar cells, whereas a significant loss of recoverin+ cone bipolar cells was observed in both groups via immunohistology and Western blot. The presynaptic marker Bassoon and the postsynaptic marker PSD95 were significantly reduced in the S100 + HSP group. Opsin+ and rhodopsin+ photoreceptors revealed no changes in either group. Thus, the inner retinal layers are affected by immunization. However, the combination of S100 and HSP27 has a stronger additive effect on the retinal synapses and AII amacrine cells.
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Affiliation(s)
- Sabrina Reinehr
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - Sandra Kuehn
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - Christina Casola
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - Dennis Koch
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - Gesa Stute
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - Pia Grotegut
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - H Burkhard Dick
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - Stephanie C Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany.
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Glaucoma Diagnostic Capability of Global and Regional Measurements of Isolated Ganglion Cell Layer and Inner Plexiform Layer. J Glaucoma 2017; 26:208-215. [PMID: 27811573 DOI: 10.1097/ijg.0000000000000572] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To compare glaucoma diagnostic capability of global/regional macular layer parameters in different-sized grids. MATERIALS AND METHODS Serial horizontal spectral-domain optical coherence tomography scans of macula were obtained. Automated macular grids with diameters of 3, 3.45, and 6 mm were used. For each grid, 10 parameters (total volume; average thicknesses in 9 regions) were obtained for 5 layers: macular retinal nerve fiber layer (mRNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), ganglion cell-inner plexiform layer (GCIPL; GCL+IPL), and ganglion cell complex (GCC; mRNFL+GCL+IPL). RESULTS Sixty-nine normal eyes (69 subjects) and 87 glaucomatous eyes (87 patients) were included. For the total volume parameter, the area under the receiver operating characteristic curves (AUCs) in 6-mm grid were larger than the AUCs in 3- and 3.45-mm grids for GCL, GCC, GCIPL, and mRNFL (all P<0.020). For the average thickness parameters, the best AUC in 6-mm grid (T2 region for GCL, IPL, and GCIPL; I2 region for mRNFL and GCC) was greater than the best AUC in 3-mm grid for GCL, GCC, and mRNFL (P<0.045). The AUC of GCL volume (0.920) was similar to those of GCC (0.920) and GCIPL (0.909) volume. The AUC of GCL T2 region thickness (0.942) was similar to those of GCC I2 region (0.942) and GCIPL T2 region (0.934) thickness. CONCLUSIONS Isolated macular GCL appears to be as good as GCC and GCIPL in glaucoma diagnosis, while IPL does not. Larger macular grids may be better at detecting glaucoma. Each layer has a characteristic region with the best glaucoma diagnostic capability.
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Selective Vulnerability of Specific Retinal Ganglion Cell Types and Synapses after Transient Ocular Hypertension. J Neurosci 2017; 36:9240-52. [PMID: 27581463 DOI: 10.1523/jneurosci.0940-16.2016] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 07/20/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Key issues concerning ganglion cell type-specific loss and synaptic changes in animal models of experimental glaucoma remain highly debated. Importantly, changes in the structure and function of various RGC types that occur early, within 14 d after acute, transient intraocular pressure elevation, have not been previously assessed. Using biolistic transfection of individual RGCs and multielectrode array recordings to measure light responses in mice, we examined the effects of laser-induced ocular hypertension on the structure and function of a subset of RGCs. Among the α-like RGCs studied, αOFF-transient RGCs exhibited higher rates of cell death, with corresponding reductions in dendritic area, dendritic complexity, and synapse density. Functionally, OFF-transient RGCs displayed decreases in spontaneous activity and receptive field size. In contrast, neither αOFF-sustained nor αON-sustained RGCs displayed decreases in light responses, although they did exhibit a decrease in excitatory postsynaptic sites, suggesting that synapse loss may be one of the earliest signs of degeneration. Interestingly, presynaptic ribbon density decreased to a greater degree in the OFF sublamina of the inner plexiform layer, corroborating the hypothesis that RGCs with dendrites stratifying in the OFF sublamina may be damaged early. Indeed, OFF arbors of ON-OFF RGCs lose complexity more rapidly than ON arbors. Our results reveal type-specific differences in RGC responses to injury with a selective vulnerability of αOFF-transient RGCs, and furthermore, an increased susceptibility of synapses in the OFF sublamina. The selective vulnerability of specific RGC types offers new avenues for the design of more sensitive functional tests and targeted neuroprotection. SIGNIFICANCE STATEMENT Conflicting reports regarding the selective vulnerability of specific retinal ganglion cell (RGC) types in glaucoma exist. We examine, for the first time, the effects of transient intraocular pressure elevation on the structure and function of various RGC types. Among the α-like RGCs studied, αOFF-transient RGCs are the most vulnerable to transient transient intraocular pressure elevation as measured by rates of cell death, morphologic alterations in dendrites and synapses, and physiological dysfunction. Specifically, we found that presynaptic ribbon density decreased to a greater degree in the OFF sublamina of the inner plexiform layer. Our results suggest selective vulnerability both of specific types of RGCs and of specific inner plexiform layer sublaminae, opening new avenues for identifying novel diagnostic and treatment targets in glaucoma.
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Akopian A, Kumar S, Ramakrishnan H, Roy K, Viswanathan S, Bloomfield SA. Targeting neuronal gap junctions in mouse retina offers neuroprotection in glaucoma. J Clin Invest 2017; 127:2647-2661. [PMID: 28604388 PMCID: PMC5490768 DOI: 10.1172/jci91948] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 04/27/2017] [Indexed: 01/26/2023] Open
Abstract
The progressive death of retinal ganglion cells and resulting visual deficits are hallmarks of glaucoma, but the underlying mechanisms remain unclear. In many neurodegenerative diseases, cell death induced by primary insult is followed by a wave of secondary loss. Gap junctions (GJs), intercellular channels composed of subunit connexins, can play a major role in secondary cell death by forming conduits through which toxic molecules from dying cells pass to and injure coupled neighbors. Here we have shown that pharmacological blockade of GJs or genetic ablation of connexin 36 (Cx36) subunits, which are highly expressed by retinal neurons, markedly reduced loss of neurons and optic nerve axons in a mouse model of glaucoma. Further, functional parameters that are negatively affected in glaucoma, including the electroretinogram, visual evoked potential, visual spatial acuity, and contrast sensitivity, were maintained at control levels when Cx36 was ablated. Neuronal GJs may thus represent potential therapeutic targets to prevent the progressive neurodegeneration and visual impairment associated with glaucoma.
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22
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Zhou X, Cheng Y, Zhang R, Li G, Yang B, Zhang S, Wu J. Alpha7 nicotinic acetylcholine receptor agonist promotes retinal ganglion cell function via modulating GABAergic presynaptic activity in a chronic glaucomatous model. Sci Rep 2017; 7:1734. [PMID: 28496108 PMCID: PMC5431927 DOI: 10.1038/s41598-017-02092-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 04/05/2017] [Indexed: 01/01/2023] Open
Abstract
Alpha-7 nicotinic acetylcholine receptor (α7-nAChR) agonists can prevent glutamate-induced excitotoxicity in cultured retinal ganglion cells (RGCs). However, the neuroprotective effects and the mechanism of action of PNU-282987, an α7-nAChR agonist, in a chronic in vivo rat glaucoma model are poorly understood. We found that elevated intraocular pressure (IOP) downregulated retinal α7-nAChR expression. Electroretinography revealed that the amplitude of the photopic negative response (PhNR) decreased in parallel with the loss of RGCs caused by elevated IOP. PNU-282987 enhanced RGC viability and function and decreased terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive signals in RGCs. Patch-clamp recordings revealed differences in the baseline frequencies and decay times of the miniature GABAergic inhibitory postsynaptic currents (mIPSCs) of RGCs between control and glaucomatous retinal slices. The results of western blotting and immunostaining showed that glutamic acid decarboxylase 65/67 and GABA deficits persisted in glaucomatous retinas and that these deficits were reversed by PNU-282987. Patch-clamp recordings also showed that PNU-282987 significantly increased the frequency and amplitude of the GABAergic mIPSCs of RGCs. The protective effects of PNU-292987 were blocked by intravitreal administration of selective GABAA receptor antagonists. The modulation of GABAergic synaptic transmission by PNU-282987 causes de-excitation of ganglion cell circuits and suppresses excitotoxic processes.
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Affiliation(s)
- Xujiao Zhou
- Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China.,Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, 200032, China.,Key Laboratory of Myopia, Ministry of Health, Shanghai, 200032, China
| | - Yun Cheng
- Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Rong Zhang
- Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Gang Li
- Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Boqi Yang
- Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Shenghai Zhang
- Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Jihong Wu
- Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China. .,Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, 200032, China. .,Key Laboratory of Myopia, Ministry of Health, Shanghai, 200032, China.
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23
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Cwerman-Thibault H, Lechauve C, Augustin S, Roussel D, Reboussin É, Mohammad A, Degardin-Chicaud J, Simonutti M, Liang H, Brignole-Baudouin F, Maron A, Debeir T, Corral-Debrinski M. Neuroglobin Can Prevent or Reverse Glaucomatous Progression in DBA/2J Mice. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2017; 5:200-220. [PMID: 28540323 PMCID: PMC5430497 DOI: 10.1016/j.omtm.2017.04.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 04/21/2017] [Indexed: 01/12/2023]
Abstract
Mitochondrial dysfunction is responsible for hereditary optic neuropathies. We wished to determine whether preserving mitochondrial bioenergetics could prevent optic neuropathy in a reliable model of glaucoma. DBA/2J mice exhibit elevated intraocular pressure, progressive degeneration of their retinal ganglion cells, and optic neuropathy that resembles glaucoma. We established that glaucoma in these mice is directly associated with mitochondrial dysfunction: respiratory chain activity was compromised in optic nerves 5 months before neuronal loss began, and the amounts of some mitochondrial proteins were reduced in retinas of glaucomatous mice. One of these proteins is neuroglobin, which has a neuroprotective function. Therefore, we investigated whether gene therapy aimed at restoring neuroglobin levels in the retina via ocular administration of an adeno-associated viral vector could reduce neuronal degeneration. The approach of treating 2-month-old mice impeded glaucoma development: few neurons died and respiratory chain activity and visual cortex activity were comparable to those in young, asymptomatic mice. When the treatment was performed in 8-month-old mice, the surviving neurons acquired new morphologic and functional properties, leading to the preservation of visual cortex activity and respiratory chain activity. The beneficial effects of neuroglobin in DBA/2J retinas confirm this protein to be a promising candidate for treating glaucoma.
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Affiliation(s)
- Hélène Cwerman-Thibault
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
- PROTECT, INSERM, Université Paris Diderot, Sorbonne Paris Cité, 75019 Paris, France
| | - Christophe Lechauve
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
- Department of Hematology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Sébastien Augustin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
| | - Delphine Roussel
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
- Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 75013 Paris, France
| | - Élodie Reboussin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
| | - Ammara Mohammad
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
- Genomic Paris Centre, Institut de Biologie de l’Ecole normale supérieure, 46 rue d’Ulm, 75230 Paris, France
| | - Julie Degardin-Chicaud
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
| | - Manuel Simonutti
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
| | - Hong Liang
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC, 28 rue de Charenton, 75012 Paris, France
| | - Françoise Brignole-Baudouin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
| | - Anne Maron
- Sanofi-Aventis, 94400 Vitry-sur-Seine, France
| | - Thomas Debeir
- Departments of Evaluation and Expertise Strategy, Science Policy and External Innovation, Sanofi, 75008 Paris, France
| | - Marisol Corral-Debrinski
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 rue Moreau, 75012 Paris, France
- PROTECT, INSERM, Université Paris Diderot, Sorbonne Paris Cité, 75019 Paris, France
- Corresponding author: Marisol Corral-Debrinski, PROTECT, INSERM (UMR1141), Université Paris Diderot, Sorbonne Paris Cité, 48 Boulevard Sérurier, 75019 Paris, France.
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24
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Vidal-Sanz M, Galindo-Romero C, Valiente-Soriano FJ, Nadal-Nicolás FM, Ortin-Martinez A, Rovere G, Salinas-Navarro M, Lucas-Ruiz F, Sanchez-Migallon MC, Sobrado-Calvo P, Aviles-Trigueros M, Villegas-Pérez MP, Agudo-Barriuso M. Shared and Differential Retinal Responses against Optic Nerve Injury and Ocular Hypertension. Front Neurosci 2017; 11:235. [PMID: 28491019 PMCID: PMC5405145 DOI: 10.3389/fnins.2017.00235] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 04/07/2017] [Indexed: 12/05/2022] Open
Abstract
Glaucoma, one of the leading causes of blindness worldwide, affects primarily retinal ganglion cells (RGCs) and their axons. The pathophysiology of glaucoma is not fully understood, but it is currently believed that damage to RGC axons at the optic nerve head plays a major role. Rodent models to study glaucoma include those that mimic either ocular hypertension or optic nerve injury. Here we review the anatomical loss of the general population of RGCs (that express Brn3a; Brn3a+RGCs) and of the intrinsically photosensitive RGCs (that express melanopsin; m+RGCs) after chronic (LP-OHT) or acute (A-OHT) ocular hypertension and after complete intraorbital optic nerve transection (ONT) or crush (ONC). Our studies show that all of these insults trigger RGC death. Compared to Brn3a+RGCs, m+RGCs are more resilient to ONT, ONC, and A-OHT but not to LP-OHT. There are differences in the course of RGC loss both between these RGC types and among injuries. An important difference between the damage caused by ocular hypertension or optic nerve injury appears in the outer retina. Both axotomy and LP-OHT induce selective loss of RGCs but LP-OHT also induces a protracted loss of cone photoreceptors. This review outlines our current understanding of the anatomical changes occurring in rodent models of glaucoma and discusses the advantages of each one and their translational value.
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Affiliation(s)
- Manuel Vidal-Sanz
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Caridad Galindo-Romero
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Francisco J Valiente-Soriano
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Francisco M Nadal-Nicolás
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Arturo Ortin-Martinez
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Giuseppe Rovere
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Manuel Salinas-Navarro
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Fernando Lucas-Ruiz
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Maria C Sanchez-Migallon
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Paloma Sobrado-Calvo
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Marcelino Aviles-Trigueros
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - María P Villegas-Pérez
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
| | - Marta Agudo-Barriuso
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la ArrixacaMurcia, Spain
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He T, Mortensen X, Wang P, Tian N. The effects of immune protein CD3ζ development and degeneration of retinal neurons after optic nerve injury. PLoS One 2017; 12:e0175522. [PMID: 28441398 PMCID: PMC5404868 DOI: 10.1371/journal.pone.0175522] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 03/27/2017] [Indexed: 02/07/2023] Open
Abstract
Major histocompatibility complex (MHC) class I molecules and their receptors play fundamental roles in neuronal death during diseases. T-cell receptors (TCR) function as MHCI receptor on T-cells and both MHCI and a key component of TCR, CD3ζ, are expressed by mouse retinal ganglion cells (RGCs) and displaced amacrine cells. Mutation of these molecules compromises the development of RGCs. We investigated whether CD3ζ regulates the development and degeneration of amacrine cells after RGC death. Surprisingly, mutation of CD3ζ not only impairs the proper development of amacrine cells expressing CD3ζ but also those not expressing CD3ζ. In contrast to effects of MHCI and its receptor, PirB, on other neurons, mutation of CD3ζ has no effect on RGC death and starburst amacrine cells degeneration after optic nerve crush. Thus, unlike MHCI and PirB, CD3ζ regulates the development of RGCs and amacrine cells but not their degeneration after optic nerve crush.
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Affiliation(s)
- Tao He
- Eye Center Remin Hospital of Wuhan University Wuhan, Hubei, PR China
- Department of Ophthalmology and Visual Science John Moran Eye Center University of Utah School of Medicine, Salt Lake City, UT, United States of America
| | - Xavier Mortensen
- Department of Ophthalmology and Visual Science John Moran Eye Center University of Utah School of Medicine, Salt Lake City, UT, United States of America
| | - Ping Wang
- Department of Ophthalmology and Visual Science John Moran Eye Center University of Utah School of Medicine, Salt Lake City, UT, United States of America
| | - Ning Tian
- Department of Ophthalmology and Visual Science John Moran Eye Center University of Utah School of Medicine, Salt Lake City, UT, United States of America
- VA Salt Lake City Health Care System, Salt Lake City, UT, United States of America
- * E-mail:
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Chang SW, Kim HI, Kim GH, Park SJ, Kim IB. Increased Expression of Osteopontin in Retinal Degeneration Induced by Blue Light-Emitting Diode Exposure in Mice. Front Mol Neurosci 2016; 9:58. [PMID: 27504084 PMCID: PMC4958628 DOI: 10.3389/fnmol.2016.00058] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 07/07/2016] [Indexed: 02/01/2023] Open
Abstract
Osteopontin (OPN) is a multifunctional adhesive glycoprotein that is implicated in a variety of pro-inflammatory as well as neuroprotective and repair-promoting effects in the brain. As a first step towards understanding the role of OPN in retinal degeneration (RD), we examined changes in OPN expression in a mouse model of RD induced by exposure to a blue light-emitting diode (LED). RD was induced in BALB/c mice by exposure to a blue LED (460 nm) for 2 h. Apoptotic cell death was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. In order to investigate changes in OPN in RD, western blotting and immunohistochemistry were performed. Anti-OPN labeling was compared to that of anti-glial fibrillary acidic protein (GFAP), which is a commonly used marker for retinal injury or stress including inflammation. OPN expression in RD retinas markedly increased at 24 h after exposure, was sustained through 72 h, and subsided at 120 h. Increased OPN expression was observed co-localized with microglial cells in the outer nuclear layer (ONL), outer plexiform layer (OPL), and subretinal space. Expression was restricted to the central retina in which photoreceptor cell death occurred. Interestingly, OPN expression in the ONL/OPL was closely associated with microglia, whereas most of the OPN plaques observed in the subretinal space were not. Immunogold electron microscopy demonstrated that OPN was distributed throughout the cytoplasm of microglia and in nearby fragments of degenerating photoreceptors. In addition, we found that OPN was induced more acutely and with greater region specificity than GFAP. These results indicate that OPN may be a more useful marker for retinal injury or stress, and furthermore act as a microglial pro-inflammatory mediator and a phagocytosis-inducing opsonin in the subretinal space. Taken together, our data suggest that OPN plays an important role in the pathogenesis of RD.
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Affiliation(s)
- Seung Wook Chang
- Department of Anatomy, College of Medicine, The Catholic University of Korea Seoul, Korea
| | - Hyung Il Kim
- Department of Anatomy, College of Medicine, The Catholic University of KoreaSeoul, Korea; Gyeongju St. Mary's Eye ClinicGyeongju, Korea
| | - Gyu Hyun Kim
- Department of Anatomy, College of Medicine, The Catholic University of KoreaSeoul, Korea; Catholic Neuroscience Institute, College of Medicine, The Catholic University of KoreaSeoul, Korea
| | - Su Jin Park
- Department of Anatomy, College of Medicine, The Catholic University of KoreaSeoul, Korea; Catholic Neuroscience Institute, College of Medicine, The Catholic University of KoreaSeoul, Korea
| | - In-Beom Kim
- Department of Anatomy, College of Medicine, The Catholic University of KoreaSeoul, Korea; Catholic Neuroscience Institute, College of Medicine, The Catholic University of KoreaSeoul, Korea; Catholic Institute for Applied Anatomy, College of Medicine, The Catholic University of KoreaSeoul, Korea
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Akopian A, Kumar S, Ramakrishnan H, Viswanathan S, Bloomfield SA. Amacrine cells coupled to ganglion cells via gap junctions are highly vulnerable in glaucomatous mouse retinas. J Comp Neurol 2016; 527:159-173. [PMID: 27411041 DOI: 10.1002/cne.24074] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 07/06/2016] [Accepted: 07/08/2016] [Indexed: 12/22/2022]
Abstract
We determined whether the structural and functional integrity of amacrine cells (ACs), the largest cohort of neurons in the mammalian retina, are affected in glaucoma. Intraocular injection of microbeads was made in mouse eyes to elevate intraocular pressure as a model of experimental glaucoma. Specific immunocytochemical markers were used to identify AC and displaced (d)ACs subpopulations in both the inner nuclear and ganglion cell layers, respectively, and to distinguish them from retinal ganglion cells (RGCs). Calretinin- and γ-aminobutyric acid (GABA)-immunoreactive (IR) cells were highly vulnerable to glaucomatous damage, whereas choline acetyltransferase (ChAT)-positive and glycinergic AC subtypes were unaffected. The AC loss began 4 weeks after initial microbead injection, corresponding to the time course of RGC loss. Recordings of electroretinogram (ERG) oscillatory potentials and scotopic threshold responses, which reflect AC and RGC activity, were significantly attenuated in glaucomatous eyes following a time course that matched that of the AC and RGC loss. Moreover, we found that it was the ACs coupled to RGCs via gap junctions that were lost in glaucoma, whereas uncoupled ACs were largely unaffected. Our results suggest that AC loss in glaucoma occurs secondary to RGC death through the gap junction-mediated bystander effect. J. Comp. Neurol. 527:159-173, 2019. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Abram Akopian
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, New York, 10036
| | - Sandeep Kumar
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, New York, 10036
| | | | - Suresh Viswanathan
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, New York, 10036
| | - Stewart A Bloomfield
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, New York, 10036
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Vied C, Ray S, Badger CD, Bundy JL, Arbeitman MN, Nowakowski RS. Transcriptomic analysis of the hippocampus from six inbred strains of mice suggests a basis for sex-specific susceptibility and severity of neurological disorders. J Comp Neurol 2016; 524:2696-710. [DOI: 10.1002/cne.23989] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 02/12/2016] [Accepted: 02/18/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Cynthia Vied
- Department of Biomedical Sciences, College of Medicine; Florida State University; Tallahassee Florida 32306
| | - Surjyendu Ray
- Department of Biomedical Sciences, College of Medicine; Florida State University; Tallahassee Florida 32306
- Department of Computer Science; Florida State University; Tallahassee Florida 32306
| | - Crystal-Dawn Badger
- Department of Biomedical Sciences, College of Medicine; Florida State University; Tallahassee Florida 32306
| | - Joseph L. Bundy
- Department of Biomedical Sciences, College of Medicine; Florida State University; Tallahassee Florida 32306
| | - Michelle N. Arbeitman
- Department of Biomedical Sciences, College of Medicine; Florida State University; Tallahassee Florida 32306
- Center for Genomics and Personalized Medicine; Florida State University; Tallahassee Florida 32306
| | - Richard S. Nowakowski
- Department of Biomedical Sciences, College of Medicine; Florida State University; Tallahassee Florida 32306
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Junoy Montolio FG, Meems W, Janssens MSA, Stam L, Jansonius NM. Lateral Inhibition in the Human Visual System in Patients with Glaucoma and Healthy Subjects: A Case-Control Study. PLoS One 2016; 11:e0151006. [PMID: 26953590 PMCID: PMC4783060 DOI: 10.1371/journal.pone.0151006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Accepted: 02/21/2016] [Indexed: 11/18/2022] Open
Abstract
In glaucoma, the density of retinal ganglion cells is reduced. It is largely unknown how this influences retinal information processing. An increase in spatial summation and a decrease in contrast gain control and contrast adaptation have been reported. A decrease in lateral inhibition might also arise. This could result in a larger than expected response to some stimuli, which could mask ganglion cell loss on functional testing (structure-function discrepancy). The aim of this study was to compare lateral inhibition between glaucoma patients and healthy subjects; we used a case-control design. Cases (n = 18) were selected to have advanced visual field loss in combination with a normal visual acuity. Controls (n = 50) were not allowed to have symptoms or signs of any eye disease. Lateral inhibition was measured psychophysically on a computer screen, with (1) a modified illusory movement experiment and (2) a contrast sensitivity (CS) test. Illusory movement was quantified by nulling it with a real movement; measure of lateral inhibition was the amount of illusory movement. CS was measured at 1 and 4 cycles per degree (cpd); measure of lateral inhibition was the difference between log CS at 4 and 1 cpd. Both measures were compared between cases and controls; analyses were adjusted for age and gender. There was no difference between cases and controls for these two measures of lateral inhibition (p = 0.58 for illusory movement; p = 0.20 for CS). The movement threshold was higher in cases than in controls (p = 0.008) and log CS was lower, at both 1 (-0.20; p = 0.008) and 4 (-0.28; p = 0.001) cpd. Our results indicate that spatially antagonistic mechanisms are not specifically affected in glaucoma, at least not in the intact center of a severely damaged visual field. This suggests that the structure-function discrepancy in glaucoma is not related to a decrease in lateral inhibition.
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Affiliation(s)
- Francisco G. Junoy Montolio
- Dept. of Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Wilma Meems
- Dept. of Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Marieke S. A. Janssens
- Dept. of Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Lucas Stam
- Dept. of Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Nomdo M. Jansonius
- Dept. of Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
- Dept. of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands
- * E-mail:
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Vidal-Sanz M, Valiente-Soriano FJ, Ortín-Martínez A, Nadal-Nicolás FM, Jiménez-López M, Salinas-Navarro M, Alarcón-Martínez L, García-Ayuso D, Avilés-Trigueros M, Agudo-Barriuso M, Villegas-Pérez MP. Retinal neurodegeneration in experimental glaucoma. PROGRESS IN BRAIN RESEARCH 2015; 220:1-35. [PMID: 26497783 DOI: 10.1016/bs.pbr.2015.04.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In rats and mice, limbar tissues of the left eye were laser-photocoagulated (LP) and ocular hypertension (OHT) effects were investigated 1 week to 6 months later. To investigate the innermost layers, retinas were examined in wholemounts using tracing from the superior colliculi to identify retinal ganglion cells (RGCs) with intact retrograde axonal transport, melanopsin immunodetection to identify intrinsically photosensitive RGCs (m(+)RGC), Brn3a immunodetection to identify most RGCs but not m(+)RGCs, RECA1 immunodetection to examine the inner retinal vessels, and DAPI staining to detect all nuclei in the GC layer. The outer retinal layers (ORLs) were examined in cross sections analyzed morphometrically or in wholemounts to study S- and L-cones. Innervation of the superior colliculi was examined 10 days to 14 weeks after LP with orthogradely transported cholera toxin subunit B. By 2 weeks, OHT resulted in pie-shaped sectors devoid of FG(+)RGCs or Brn3a(+)RGCs but with large numbers of DAPI(+)nuclei. Brn3a(+)RGCs were significantly greater than FG(+)RGCs, indicating the survival of large numbers of RGCs with their axonal transport impaired. The inner retinal vasculature showed no abnormalities that could account for the sectorial loss of RGCs. m(+)RGCs decreased to approximately 50-51% in a diffuse loss across the retina. Cross sections showed focal areas of degeneration in the ORLs. RGC loss at 1m diminished to 20-25% and did not progress further with time, whereas the S- and L-cone populations diminished progressively up to 6m. The retinotectal projection was reduced by 10 days and did not progress further. LP-induced OHT results in retrograde degeneration of RGCs and m(+)RGCs, severe damage to the ORL, and loss of retinotectal terminals.
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Affiliation(s)
- Manuel Vidal-Sanz
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain.
| | - Francisco J Valiente-Soriano
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Arturo Ortín-Martínez
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Francisco M Nadal-Nicolás
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Manuel Jiménez-López
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Manuel Salinas-Navarro
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Luis Alarcón-Martínez
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Diego García-Ayuso
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Marcelino Avilés-Trigueros
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Marta Agudo-Barriuso
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
| | - Maria P Villegas-Pérez
- Departamento de Oftalmología, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), Murcia, Spain
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Valiente-Soriano FJ, Salinas-Navarro M, Jiménez-López M, Alarcón-Martínez L, Ortín-Martínez A, Bernal-Garro JM, Avilés-Trigueros M, Agudo-Barriuso M, Villegas-Pérez MP, Vidal-Sanz M. Effects of ocular hypertension in the visual system of pigmented mice. PLoS One 2015; 10:e0121134. [PMID: 25811653 PMCID: PMC4374934 DOI: 10.1371/journal.pone.0121134] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Accepted: 02/12/2015] [Indexed: 11/21/2022] Open
Abstract
To study the effects of ocular hypertension (OHT) on the visual system of C57BL/6 pigmented mice, the limbal and episcleral veins of the left eye were laser photocoagulated (LP). LP increased the intraocular pressure during the first five days (d), reaching basal values at 7d. To investigate the effect of OHT on the retinal ganglion cell (RGC) retrograde axonal transport, hydroxistilbamidine methanesulfonate (OHSt) was applied to both superior colliculi (SCi) and the retinas were dissected 2 or 4 weeks after LP. To determine RGC survival, these same retinas were immunoreacted against Brn3a (general RGC population) and melanopsin (intrinsically photosensitive RGCs, m+RGCs). To study whether OHT affected non-RGC neurons in the ganglion cell layer (GCL), RGCs were immunodetected with Brn3a and all GCL nuclei counterstained with DAPI in a group of animals examined 4 weeks post-LP. Innervation of the SCi was examined at 10 days, 8 or 14 weeks after LP with the orthogradely transported cholera toxin subunit-B. OHT resulted in diffuse and sectorial loss of OHSt+RGCs (50% at 2 weeks and 62% at 4 weeks) and in a comparable loss of Brn3a+RGCs at the same time intervals. m+RGCs decreased to 59% at 2 weeks and to 46% at 4 weeks, such loss was diffuse, did not parallel the sectorial loss of the general RGC population and was more severe in the superior-temporal retina. In the GCL, cell loss is selective for RGCs and does not affect other non-RGC neurons. The retinotectal innervation appeared significantly reduced at 10 days (55.7%) and did not progress further up to 14 weeks (46.6%). Thus, LP-induced OHT results in retrograde degeneration of RGCs and m+RGCs, as well as in the loss of CTB-labelled retinotectal terminals.
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Affiliation(s)
- Francisco J. Valiente-Soriano
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia. 30.100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca) 30.100 Murcia, Spain
| | - Manuel Salinas-Navarro
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia. 30.100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca) 30.100 Murcia, Spain
| | - Manuel Jiménez-López
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia. 30.100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca) 30.100 Murcia, Spain
| | - Luis Alarcón-Martínez
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia. 30.100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca) 30.100 Murcia, Spain
| | - Arturo Ortín-Martínez
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia. 30.100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca) 30.100 Murcia, Spain
| | - José M. Bernal-Garro
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia. 30.100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca) 30.100 Murcia, Spain
| | - Marcelino Avilés-Trigueros
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia. 30.100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca) 30.100 Murcia, Spain
| | - Marta Agudo-Barriuso
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia. 30.100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca) 30.100 Murcia, Spain
| | - María P. Villegas-Pérez
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia. 30.100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca) 30.100 Murcia, Spain
| | - Manuel Vidal-Sanz
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia. 30.100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca) 30.100 Murcia, Spain
- * E-mail:
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Ortín-Martínez A, Salinas-Navarro M, Nadal-Nicolás FM, Jiménez-López M, Valiente-Soriano FJ, García-Ayuso D, Bernal-Garro JM, Avilés-Trigueros M, Agudo-Barriuso M, Villegas-Pérez MP, Vidal-Sanz M. Laser-induced ocular hypertension in adult rats does not affect non-RGC neurons in the ganglion cell layer but results in protracted severe loss of cone-photoreceptors. Exp Eye Res 2015; 132:17-33. [PMID: 25576772 DOI: 10.1016/j.exer.2015.01.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 11/19/2014] [Accepted: 01/07/2015] [Indexed: 01/09/2023]
Abstract
To investigate the long-term effects of laser-photocoagulation (LP)-induced ocular hypertension (OHT) in the innermost and outermost (outer-nuclear and outer segment)-retinal layers (ORL). OHT was induced in the left eye of adult rats. To investigate the ganglion cell layer (GCL) wholemounts were examined at 1, 3 or 6 months using Brn3a-immunodetection to identify retinal ganglion cells (RGCs) and DAPI-staining to detect all nuclei in this layer. To study the effects of LP on the ORL up to 6 months, retinas were: i) fresh extracted to quantify the levels of rod-, S- and L-opsin; ii) cut in cross-sections for morphometric analysis, or; iii) prepared as wholemounts to quantify and study retinal distributions of entire populations of RGCs (retrogradely labeled with fluorogold, FG), S- and L-cones (immunolabeled). OHT resulted in wedge-like sectors with their apex on the optic disc devoid of Brn3a(+)RGCs but with large numbers of DAPI(+)nuclei. The levels of all opsins diminished by 2 weeks and further decreased to 20% of basal-levels by 3 months. Cross-sections revealed focal areas of ORL degeneration. RGC survival at 15 days represented approximately 28% and did not change with time, whereas the S- and L-cone populations diminished to 65% and 80%, or to 20 and 35% at 1 or 6 months, respectively. In conclusion, LP induces in the GCL selective RGCs loss that does not progress after 1 month, and S- and L-cone loss that progresses for up to 6 months. Thus, OHT results in severe damage to both the innermost and the ORL.
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Affiliation(s)
- Arturo Ortín-Martínez
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain
| | - Manuel Salinas-Navarro
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain
| | - Francisco Manuel Nadal-Nicolás
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain
| | - Manuel Jiménez-López
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain
| | - Francisco Javier Valiente-Soriano
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain
| | - Diego García-Ayuso
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain
| | - José Manuel Bernal-Garro
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain
| | - Marcelino Avilés-Trigueros
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain
| | - Marta Agudo-Barriuso
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain
| | - María Paz Villegas-Pérez
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain
| | - Manuel Vidal-Sanz
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, and Instituto Murciano de Investigación Biosanitaria Virgen de la Arrixaca (IMIB-Arrixaca), 30100 Murcia, Spain.
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Li HY, Ruan YW, Ren CR, Cui Q, So KF. Mechanisms of secondary degeneration after partial optic nerve transection. Neural Regen Res 2014; 9:565-74. [PMID: 25206855 PMCID: PMC4146235 DOI: 10.4103/1673-5374.130093] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/05/2014] [Indexed: 01/23/2023] Open
Abstract
Secondary degeneration occurs commonly in the central nervous system after traumatic injuries and following acute and chronic diseases, including glaucoma. A constellation of mechanisms have been shown to be associated with secondary degeneration including apoptosis, necrosis, autophagy, oxidative stress, excitotoxicity, derangements in ionic homeostasis and calcium influx. Glial cells, such as microglia, astrocytes and oligodendrocytes, have also been demonstrated to take part in the process of secondary injury. Partial optic nerve transection is a useful model which was established about 13 years ago. The merit of this model compared with other optic nerve injury models used for glaucoma study, including complete optic nerve transection model and optic nerve crush model, is the possibility to separate primary degeneration from secondary degeneration in location. Therefore, it provides a good tool for the study of secondary degeneration. This review will focus on the research progress of the mechanisms of secondary degeneration using partial optic nerve transection model.
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Affiliation(s)
- Hong-Ying Li
- Department of Ophthalmology, the University of Hong Kong, Hong Kong Special Administrative Region, China ; State Key Laboratory of Brain and Cognitive Science, the University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Yi-Wen Ruan
- GHM Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong Province, China ; Guangdong Key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou, Guangdong Province, China
| | - Chao-Ran Ren
- GHM Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong Province, China ; Guangdong Key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou, Guangdong Province, China
| | - Qi Cui
- GHM Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong Province, China ; Guangdong Key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou, Guangdong Province, China
| | - Kwok-Fai So
- Department of Ophthalmology, the University of Hong Kong, Hong Kong Special Administrative Region, China ; GHM Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong Province, China ; Guangdong Key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou, Guangdong Province, China ; State Key Laboratory of Brain and Cognitive Science, the University of Hong Kong, Hong Kong Special Administrative Region, China
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Akopian A, Atlasz T, Pan F, Wong S, Zhang Y, Völgyi B, Paul DL, Bloomfield SA. Gap junction-mediated death of retinal neurons is connexin and insult specific: a potential target for neuroprotection. J Neurosci 2014; 34:10582-91. [PMID: 25100592 PMCID: PMC4200109 DOI: 10.1523/jneurosci.1912-14.2014] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 06/06/2014] [Accepted: 06/27/2014] [Indexed: 01/02/2023] Open
Abstract
Secondary cell death via gap junctions (GJs) plays a role in the propagation of neuronal loss under a number of degenerative disorders. Here, we examined the role of GJs in neuronal death in the retina, which has arguably the most diverse expression of GJs in the CNS. Initially, we induced apoptotic death by injecting single retinal ganglion cells and glia with cytochrome C and found that this resulted in the loss of neighboring cells to which they were coupled via GJs. We next found that pharmacological blockade of GJs eradicated nearly all amacrine cell loss and reduced retinal ganglion cell loss by ∼70% after induction of either excitotoxic or ischemic insult conditions. These data indicate that the GJ-mediated secondary cell death was responsible for the death of most cells. Whereas genetic deletion of the GJ subunit Cx36 increased cell survivability by ∼50% under excitotoxic condition, cell loss in Cx45 knock-out mouse retinas was similar to that seen in wild-type mice. In contrast, ablation of Cx45 reduced neuronal loss by ∼50% under ischemic insult, but ablation of Cx36 offered no protection. Immunolabeling of the connexins showed differential changes in protein expression consistent with their differing roles in propagating death signals under the two insults. These data indicate that secondary cell death is mediated by different cohorts of GJs dependent on the connexins they express and the type of initial insult. Our results suggest that targeting specific connexins offers a novel therapeutic strategy to reduce progressive cell loss under different neurodegenerative conditions.
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Affiliation(s)
- Abram Akopian
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, New York 10036, Department of Physiology & Neuroscience, New York University School of Medicine, New York, New York 10016
| | - Tamas Atlasz
- Department of Ophthalmology, New York University School of Medicine, New York, New York 10016, and
| | - Feng Pan
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, New York 10036, Department of Physiology & Neuroscience, New York University School of Medicine, New York, New York 10016
| | - Sze Wong
- Department of Physiology & Neuroscience, New York University School of Medicine, New York, New York 10016
| | - Yi Zhang
- Department of Physiology & Neuroscience, New York University School of Medicine, New York, New York 10016
| | - Béla Völgyi
- Department of Ophthalmology, New York University School of Medicine, New York, New York 10016, and
| | - David L Paul
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
| | - Stewart A Bloomfield
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, New York 10036, Department of Physiology & Neuroscience, New York University School of Medicine, New York, New York 10016, Department of Ophthalmology, New York University School of Medicine, New York, New York 10016, and
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PGC-1α signaling coordinates susceptibility to metabolic and oxidative injury in the inner retina. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 184:1017-1029. [PMID: 24508229 DOI: 10.1016/j.ajpath.2013.12.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 11/29/2013] [Accepted: 12/05/2013] [Indexed: 02/06/2023]
Abstract
Retinal ganglion cells (RGCs), used as a common model of central nervous system injury, are particularly vulnerable to metabolic and oxidative damage. However, molecular mechanisms underlying this sensitivity have not been determined in vivo. PGC-1α (encoded by PPARGC1A) regulates adaptive metabolism and oxidative stress responses in a tissue- and cell-specific manner. Aberrant PGC-1α signaling is implicated in neurodegeneration, but the mechanism underlying its role in central nervous system injury remains unclear. We provide evidence from a mouse model that PGC-1α expression and activity are induced in adult retina in response to metabolic and oxidative challenge. Deletion of Ppargc1a dramatically increased RGC loss, in association with dysregulated expression of PGC-1α target metabolic and oxidative stress response genes, including Hmox1 (encoding HO-1), Tfam, and Vegfa. Vehicle-treated and naive Ppargc1a(-/-) mice also showed mild RGC loss, and surprisingly prominent and consistent retinal astrocyte reactivity. These cells critically regulate metabolic homeostasis in the inner retina. We show that PGC-1α signaling (not previously studied in glia) regulates detoxifying astrocyte responses to hypoxic and oxidative stresses. Finally, PGC-1α expression was modulated in the inner retina with age and in a model of chronic optic neuropathy. These data implicate PGC-1α signaling as an important regulator of astrocyte reactivity and RGC homeostasis to coordinate pathogenic susceptibility to metabolic and oxidative injury in the inner retina.
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Dietary ω-3 deficiency and IOP insult are additive risk factors for ganglion cell dysfunction. J Glaucoma 2013; 22:269-77. [PMID: 23221900 DOI: 10.1097/ijg.0b013e318237cac7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
AIM Dietary deficiencies in ω-3 polyunsaturated fatty acids are known to effect retinal function including retinal ganglion cell (RGC) activity, which may have implications for glaucoma. In this study we consider retinal function after dietary manipulation and intraocular pressure (IOP) stress designed to compromise RGCs. METHODS Sprague-Dawley dams were fed either ω-3 sufficient (ω-3, n=15) or deficient (ω-3, n=16) diets 5 weeks before conception with pups subsequently weaned onto their mothers diets. At 20 weeks of age, acute IOP elevation was induced repeatedly through anterior chamber cannulation to 70 mm Hg for 1 hour on 3 separate occasions separated by 1 week. Electroretinograms were recorded 1 week after each IOP elevation to assay the photoreceptors (PIII), ON-bipolar cells (PII), and ganglion/amacrine cells (STR). RESULTS Repeat IOP insult results in a specific RGC dysfunction (pSTR -14.5%, P<0.035) as does ω-3 deficiency (-26.4%, P<0.01). However, the combination of both causes an even larger RGC functional loss (-40.1%, P<0.001) than does either diet or IOP insult in isolation (P<0.001). CONCLUSIONS Both ω-3 deficiency and repeat acute IOP insult cause RGC dysfunction and the combination of these factors results in a cumulative effect. Our data indicate that sufficient dietary ω-3 improves RGC function making it less susceptible to IOP insult.
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Functional protective effects of long-term memantine treatment in the DBA/2J mouse. Doc Ophthalmol 2013; 126:221-32. [DOI: 10.1007/s10633-013-9380-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 03/04/2013] [Indexed: 01/02/2023]
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Fuchs M, Scholz M, Sendelbeck A, Atorf J, Schlegel C, Enz R, Brandstätter JH. Rod photoreceptor ribbon synapses in DBA/2J mice show progressive age-related structural changes. PLoS One 2012; 7:e44645. [PMID: 22957094 PMCID: PMC3434146 DOI: 10.1371/journal.pone.0044645] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 08/06/2012] [Indexed: 02/06/2023] Open
Abstract
The DBA/2J mouse is a commonly used animal model in glaucoma research. The eyes of DBA/2J mice show severe age-related changes that finally lead to the degeneration of retinal ganglion cells and the optic nerve. Recent electroretinogram studies identified functional deficits, which suggest that also photoreceptor cells are involved in the pathological processes occurring in the DBA/2J mouse retina. In a comparative study, we examined anatomical and molecular changes in the retinae of DBA/2J and C57BL/6 control mice with light and electron microscopy and with PCR analyses. In the retina of the DBA/2J mouse, we found a thinning of the outer plexiform layer, the first synaptic layer in the transfer of visual signals, and age-dependent and progressive degenerative structural changes at rod photoreceptor ribbon synapses. The structural ribbon changes represent a photoreceptor synaptic phenotype that has not yet been described in this animal model of secondary angle-closure glaucoma. Furthermore, genes of the classical complement cascade were upregulated in the photoreceptor cells of aging DBA/2J mice, suggesting a putative link between ribbon synapse degradation and the innate immune system.
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Affiliation(s)
- Michaela Fuchs
- Department of Biology, Animal Physiology, FAU Erlangen-Nuremberg, Erlangen, Germany
| | - Michael Scholz
- Institut für Anatomie Lehrstuhl II, FAU Erlangen-Nuremberg, Erlangen, Germany
| | - Anna Sendelbeck
- Department of Biology, Animal Physiology, FAU Erlangen-Nuremberg, Erlangen, Germany
| | - Jenny Atorf
- Department of Ophthalmology, University Hospital Erlangen, Erlangen, Germany
| | - Christine Schlegel
- Department of Biology, Animal Physiology, FAU Erlangen-Nuremberg, Erlangen, Germany
| | - Ralf Enz
- Institute for Biochemistry, FAU Erlangen-Nuremberg, Erlangen, Germany
- * E-mail: (RE); (JHB)
| | - Johann Helmut Brandstätter
- Department of Biology, Animal Physiology, FAU Erlangen-Nuremberg, Erlangen, Germany
- * E-mail: (RE); (JHB)
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Calkins DJ. Critical pathogenic events underlying progression of neurodegeneration in glaucoma. Prog Retin Eye Res 2012; 31:702-19. [PMID: 22871543 DOI: 10.1016/j.preteyeres.2012.07.001] [Citation(s) in RCA: 230] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2012] [Revised: 07/16/2012] [Accepted: 07/18/2012] [Indexed: 01/03/2023]
Abstract
Glaucoma is a common optic neuropathy with a complex etiology often linked to sensitivity to intraocular pressure. Though the precise mechanisms that mediate or transduce this sensitivity are not clear, the axon of the retinal ganglion cell appears to be vulnerable to disease-relevant stressors early in progression. One reason may be because the axon is generally thin for both its unmyelinated and myelinated segment and much longer than the thicker unmyelinated axons of other excitatory retinal neurons. This difference may predispose the axon to metabolic and oxidative injury, especially at distal sites where pre-synaptic terminals form connections in the brain. This idea is consistent with observations of early loss of anterograde transport at central targets and other signs of distal axonopathy that accompany physiological indicators of progression. Outright degeneration of the optic projection ensues after a critical period and, at least in animal models, is highly sensitive to cumulative exposure to elevated pressure in the eye. Stress emanating from the optic nerve head can induce not only distal axonopathy with aspects of dying back neuropathy, but also Wallerian degeneration of the optic nerve and tract and a proximal program involving synaptic and dendritic pruning in the retina. Balance between progressive and acute mechanisms likely varies with the level of stress placed on the unmyelinated axon as it traverses the nerve head, with more acute insult pushing the system toward quicker disassembly. A constellation of signaling factors likely contribute to the transduction of stress to the axon, so that degenerative events along the length of the optic projection progress in retinotopic fashion. This pattern leads to well-defined sectors of functional depletion, even at distal-most sites in the pathway. While ganglion cell somatic drop-out is later in progression, some evidence suggests that synaptic and dendritic pruning in the retina may be a more dynamic process. Structural persistence both in the retina and in central projection sites offers the possibility that intrinsic self-repair pathways counter pathogenic mechanisms to delay as long as possible outright loss of tissue.
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Affiliation(s)
- David J Calkins
- Department of Ophthalmology and Visual Sciences, The Vanderbilt Eye Institute, Vanderbilt University School of Medicine, 11435 MRB IV, 2215B Garland Avenue, Nashville, TN 37232, USA.
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Pascale A, Drago F, Govoni S. Protecting the retinal neurons from glaucoma: lowering ocular pressure is not enough. Pharmacol Res 2012; 66:19-32. [PMID: 22433276 DOI: 10.1016/j.phrs.2012.03.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 02/28/2012] [Accepted: 03/05/2012] [Indexed: 01/01/2023]
Abstract
The retina is theater of a number of biochemical reactions allowing, within its layers, the conversion of light impulses into electrical signals. The axons of the last neuronal elements, the ganglion cells, form the optic nerve and transfer the signals to the brain. Therefore, an appropriate cellular communication, not only within the different retinal cells, but also between the retina itself and the other brain structures, is fundamental. One of the most diffuse pathologies affecting retinal function and communication, which thus reverberates in the whole visual system, is glaucoma. This insidious disease is characterized by a progressive optic nerve degeneration and sight loss which may finally lead to irreversible blindness. Nevertheless, the progressive nature of this pathology offers an opportunity for therapeutic intervention. To better understand the cellular processes implicated in the development of glaucoma useful to envision a targeted pharmacological strategy, this manuscript first examines the complex cellular and functional organization of the retina and subsequently identifies the targets sensitive to neurodegeneration. Within this context, high ocular pressure represents a key risk factor. However, recent literature findings highlight the concept that lowering ocular pressure is not enough to prevent/slow down glaucomatous damage, suggesting the importance of combining the hypotensive treatment with other pharmacological approaches, such as the use of neuroprotectants. Therefore, this important and more novel aspect is extensively considered in this review, also emphasizing the idea that the neuroprotective strategy should be extended to the entire visual system and not restricted to the retina.
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Affiliation(s)
- Alessia Pascale
- Department of Drug Sciences, Section of Pharmacology, University of Pavia, Pavia, Italy
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41
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Vidal-Sanz M, Salinas-Navarro M, Nadal-Nicolás FM, Alarcón-Martínez L, Valiente-Soriano FJ, Miralles de Imperial J, Avilés-Trigueros M, Agudo-Barriuso M, Villegas-Pérez MP. Understanding glaucomatous damage: Anatomical and functional data from ocular hypertensive rodent retinas. Prog Retin Eye Res 2012; 31:1-27. [DOI: 10.1016/j.preteyeres.2011.08.001] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 08/23/2011] [Accepted: 08/24/2011] [Indexed: 12/24/2022]
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Gunn DJ, Gole GA, Barnett NL. Specific amacrine cell changes in an induced mouse model of glaucoma. Clin Exp Ophthalmol 2011; 39:555-63. [PMID: 21176046 DOI: 10.1111/j.1442-9071.2010.02488.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND To investigate retinal cell population changes under chronic elevated intraocular pressure in an inducible mouse model of glaucoma. METHODS Chronic unilateral ocular hypertension was induced in 40 C57BL6/J mice by ablation of the limbal episcleral veins. After 5, 20, 40 and 60 days of elevated intraocular pressure, specific retinal cell types were identified and/or quantified by immunohistochemistry for protein kinase C α, glial fibrillary acidic protein, parvalbumin and calretinin. Apoptotic cells were identified by TUNEL and cleaved caspase-3 immunohistochemistry. RESULTS Elevations in intraocular pressure in the range 22-30 mmHg were developed and sustained in mice for up to 60 days. Protein kinase C α immunoreactivity localized to bipolar cells was unchanged. We observed a rapid increase in glial fibrillary acidic protein expression in Müller cells and a progressive loss of parvalbumin-labelled ganglion cells. After 60 days of elevated intraocular pressure, calretinin-immunoreactive cell counts declined by 55.4% and 46.4% in the inner nuclear and ganglion cell layers, respectively. However, at all time points examined, the markers of cell death were only observed in the ganglion cell layer, not in the inner nuclear layer. CONCLUSIONS In addition to ganglion cell death and reactive Müller cell changes, chronic experimental elevation of intraocular pressure alters calcium-binding protein immunohistochemistry in amacrine cells. However, these changes are not indicative of amacrine cell loss but may represent early indicators of cellular distress that precede physiological dysfunction or cell death.
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Affiliation(s)
- David J Gunn
- The University of Queensland, Perinatal Research Centre, Brisbane, Queensland, Australia
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Bernstein SL, Guo Y. Changes in cholinergic amacrine cells after rodent anterior ischemic optic neuropathy (rAION). Invest Ophthalmol Vis Sci 2011; 52:904-10. [PMID: 20847114 DOI: 10.1167/iovs.10-5247] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Displaced cholinergic amacrine cell neurons comprise a significant fraction of the retinal ganglion cell (RGC) layer. Rodent anterior ischemic optic neuropathy (rAION) is an optic nerve infarct, which results in RGC loss in mice. The goal was to determine whether rAION produces changes in amacrine cell neurons. METHODS rAION was generated in transgenic mice carrying a cyan fluorescent reporter protein (CFP) gene linked to the Thy-1 promoter, which expresses CFP in RGCs. rAION was induced with standard parameters. Retinas were examined pre-and post-induction by retinal fundus microscopy. rAION induction severity was scored by changes in retinal transparency and RGC loss. Cholinergic amacrine cells were identified via choline acetyltransferase (ChAT) immunohistochemistry. ChAT and CFP expression was evaluated in flat-mounted retinas examined by confocal microscopy and western analysis. RESULTS Moderate rAION induction levels (defined as early retention of retinal transparency and <70% RGC loss) did not alter amacrine cell numbers in the RGC layer, but changed the relative levels of ChAT expression by immunohistochemistry. No changes in total ChAT protein were seen. Severe rAION induction (defined as loss of retinal transparency and >70% RGC loss) resulted in a trend toward amacrine cell loss and decreased ChAT protein levels. CONCLUSIONS There is wide disparity in mouse rAION induction levels using standardized parameters. Moderate rAION induction levels without direct retinal compromise produces isolated RGC loss, with displaced amacrine cell changes likely due to changes in RGC-amacrine communication. Severe rAION induction results in both RGC and amacrine cell loss, possibly due to intra-retinal ischemic changes.
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Affiliation(s)
- Steven L Bernstein
- Departments of Ophthalmology, University of Maryland at Baltimore, School of Medicine, Baltimore, Maryland 21201, USA.
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Morrison JC, Cepurna Ying Guo WO, Johnson EC. Pathophysiology of human glaucomatous optic nerve damage: insights from rodent models of glaucoma. Exp Eye Res 2010; 93:156-64. [PMID: 20708000 DOI: 10.1016/j.exer.2010.08.005] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 07/28/2010] [Accepted: 08/03/2010] [Indexed: 10/19/2022]
Abstract
Understanding mechanisms of glaucomatous optic nerve damage is essential for developing effective therapies to augment conventional pressure-lowering treatments. This requires that we understand not only the physical forces in play, but the cellular responses that translate these forces into axonal injury. The former are best understood by using primate models, in which a well-developed lamina cribrosa, peripapillary sclera and blood supply are most like that of the human optic nerve head. However, determining cellular responses to elevated intraocular pressure (IOP) and relating their contribution to axonal injury require cell biology techniques, using animals in numbers sufficient to perform reliable statistical analyses and draw meaningful conclusions. Over the years, models of chronically elevated IOP in laboratory rats and mice have proven increasingly useful for these purposes. While lacking a distinct collagenous lamina cribrosa, the rodent optic nerve head (ONH) possesses a cellular arrangement of astrocytes, or glial lamina, that ultrastructurally closely resembles that of the primate. Using these tools, major insights have been gained into ONH and the retinal cellular responses to elevated IOP that, in time, can be applied to the primate model and, ultimately, human glaucoma.
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Affiliation(s)
- John C Morrison
- The Kenneth C. Swan Ocular Neurobiology Laboratory, Casey Eye Institute, Oregon Health and Science University, CERES, 3375 SW Terwilliger Bvld, Portland, OR 97239, USA.
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Guo L, Normando EM, Nizari S, Lara D, Cordeiro MF. Tracking longitudinal retinal changes in experimental ocular hypertension using the cSLO and spectral domain-OCT. Invest Ophthalmol Vis Sci 2010; 51:6504-13. [PMID: 20688741 DOI: 10.1167/iovs.10-5551] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
PURPOSE Involvement of the outer retina is controversial in glaucoma. The aim of this study was to test, first, whether the outer retina is affected in experimental ocular hypertension (OHT) and, second, whether whole retinal thickness can be used as a surrogate marker of glaucomatous change. METHODS OHT was surgically induced in 20 Dark Agouti rats. Animals were imaged using a modified Spectralis OCT (Heidelberg Engineering, Heidelberg, Germany) at baseline and at 3 and 8 weeks after OHT induction. Measurements were recorded for whole and individual retinal layer thickness in four regions-temporal, superior, nasal, and inferior-around the optic nerve head. RESULTS Whole retinal thickness in normal eyes was 172.19 ± 5.17 μm, with no significant regional differences. OHT caused a significant reduction in whole retinal thickness and the outer nuclear layer (ONL) at 3 and 8 weeks (P < 0.05), along with the expected thinning of the retinal nerve fiber layer (RNFL). Whole retinal thickness correlated well with RNFL (P = 0.035) and ONL (P ≤ 0.001) changes. Sensitivity of RNFL and ONL to IOP exposure appeared greater at 3 than at 8 weeks. In addition, regional profiles were significantly altered in the ONL and RNFL after OHT induction. CONCLUSIONS Adaptation of the Spectralis OCT enables tracking of structural damage in experimental rat OHT. Here the authors show evidence of glaucomatous damage in the outer retinal layers of this model with significant regional changes and highlight whole retinal thickness in the rat as a useful surrogate marker of inner and outer retinal changes. The authors believe that the OCT data can provide useful information with regard to clinical management.
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Affiliation(s)
- Li Guo
- Visual Neuroscience, UCL Institute of Ophthalmology, London, United Kingdom.
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Gallagher SK, Witkovsky P, Roux MJ, Low MJ, Otero-Corchon V, Hentges ST, Vigh J. beta-Endorphin expression in the mouse retina. J Comp Neurol 2010; 518:3130-48. [PMID: 20533364 PMCID: PMC3095846 DOI: 10.1002/cne.22387] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Evidence showing expression of endogenous opioids in the mammalian retina is sparse. In the present study we examined a transgenic mouse line expressing an obligate dimerized form of Discosoma red fluorescent protein (DsRed) under the control of the pro-opiomelanocortin promoter and distal upstream regulatory elements to assess whether pro-opiomelanocortin peptide (POMC), and its opioid cleavage product, beta-endorphin, are expressed in the mouse retina. Using double label immunohistochemistry we found that DsRed fluorescence was restricted to a subset of GAD-67-positive cholinergic amacrine cells of both orthotopic and displaced subtypes. About 50% of cholinergic amacrine cells colocalized DsRed and a large fraction of DsRed-expressing amacrine cells was positive for beta-endorphin immunostaining, whereas beta-endorphin-immunoreactive neurons were absent in retinas of POMC null mice. Our findings contribute to a growing body of evidence demonstrating that opioid peptides are an integral component of vertebrate retinas, including those of mammals.
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Affiliation(s)
- Shannon K. Gallagher
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Paul Witkovsky
- Department of Ophthalmology, New York University School of Medicine, New York, NY 10016, USA
| | - Michel J. Roux
- Department of Neurobiology and Genetics, IGBMC, CNRS UMR 7104, Inserm U 964, Université de Strasbourg, F-67404 Illkirch, France
| | - Malcolm J. Low
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Veronica Otero-Corchon
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Shane T. Hentges
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Jozsef Vigh
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
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Retinal ganglion cell death induced by endoplasmic reticulum stress in a chronic glaucoma model. Brain Res 2010; 1308:158-66. [DOI: 10.1016/j.brainres.2009.10.025] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2009] [Revised: 10/09/2009] [Accepted: 10/09/2009] [Indexed: 12/31/2022]
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Head-up tilt lowers IOP and improves RGC dysfunction in glaucomatous DBA/2J mice. Exp Eye Res 2009; 90:452-60. [PMID: 20036238 DOI: 10.1016/j.exer.2009.12.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Revised: 12/09/2009] [Accepted: 12/14/2009] [Indexed: 12/15/2022]
Abstract
The inbred DBA/2J (D2) mouse strain is a well established model of spontaneously elevated intraocular pressure (IOP), progressive glaucomatous loss of retinal ganglion cells (RGCs), and early damage of RGC axons at the level of optic nerve head. Pattern electroretinogram (PERG) studies have shown that surviving RGCs in mice 6-12-month-old may be dysfunctional. RGC dysfunction seems to be IOP-dependent, since it may be exacerbated by means of acute IOP elevation with head-down body tilt. Here we test the hypothesis that head-up body posture lowers IOP, resulting in improvement of PERG amplitude in aged D2 mice with glaucoma. We show that head-up body tilt induces age-independent IOP lowering whose magnitude increases with the angle of tilt. For a fixed angle (-60 degrees ) of head-up tilt, IOP progressively decreases with a time constant of about 5 min and stabilizes at a value lower by about 5-6 mm Hg compared to the baseline. Head-up tilt also results in an improvement of PERG amplitude in older D2 mice with glaucoma but not in younger D2 mice without glaucoma. Improvement of PERG amplitude in aged D2 mice upon head-up-induced IOP lowering is consistent with the idea that RGCs undergo a stage of IOP-dependent, reversible dysfunction before death. The head-up IOP/PERG protocol may represent a non-invasive way to probe the potential for recovery of RGC dysfunction in D2 mice.
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A Thy1-CFP DBA/2J mouse line with cyan fluorescent protein expression in retinal ganglion cells. Vis Neurosci 2009; 26:453-65. [PMID: 19930759 DOI: 10.1017/s095252380999023x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A DBA/2J (D2) transgenic mouse line with cyan fluorescent protein (CFP) reporter expression in ganglion cells was developed for the analysis of ganglion cells during progressive glaucoma. The Thy1-CFP D2 (CFP-D2) line was created by congenically breeding the D2 line, which develops pigmentary glaucoma, and the Thy1-CFP line, which expresses CFP in ganglion cells. Microsatellite marker analysis of CFP-D2 progeny verified the genetic inclusion of the D2 isa and ipd loci. Specific mutations within these loci lead to dysfunctional melanosomal proteins and glaucomatous phenotype in D2 mice. Polymerase chain reaction analysis confirmed the inclusion of the Thy1-CFP transgene. CFP-fluorescent ganglion cells, 6-20 microm in diameter, were distributed in all retinal regions, CFP processes were throughout the inner plexiform layer, and CFP-fluorescent axons were in the fiber layer and optic nerve head. Immunohistochemistry with antibodies to ganglion cell markers NF-L, NeuN, Brn3a, and SMI32 was used to confirm CFP expression in ganglion cells. Immunohistochemistry with antibodies to amacrine cell markers HPC-1 and ChAT was used to confirm weak CFP expression in cholinergic amacrine cells. CFP-D2 mice developed a glaucomatous phenotype, including iris disease, ganglion cell loss, attrition of the fiber layer, and elevated intraocular pressure. A CFP-D2 transgenic line with CFP-expressing ganglion cells was developed, which has (1) a predominantly D2 genetic background, (2) CFP-expressing ganglion cells, and (3) age-related progressive glaucoma. This line will be of value for experimental studies investigating ganglion cells and their axons in vivo and in vitro during the progressive development of glaucoma.
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Lei Y, Garrahan N, Hermann B, Fautsch MP, Johnson DH, Hernandez MR, Boulton M, Morgan JE. Topography of neuron loss in the retinal ganglion cell layer in human glaucoma. Br J Ophthalmol 2009; 93:1676-9. [PMID: 19671529 DOI: 10.1136/bjo.2009.159210] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
AIM To determine if retinal ganglion cell (RGC) loss influences the loss of surrounding RGCs to generate clustered patterns of cell death in human glaucoma. It is hypothesised that retinal ganglion cell loss accelerates the loss of surrounding cells to generate, at a local, cellular scale, clustered patterns of retinal of RGC death. The absence of these interactions would result in a diffuse pattern RGC loss. METHOD Six glaucomatous retinas (67-83 years old) and six age-matched control retinas (61-89 years old) were prepared as wholemounts and stained by 4',6-diamidino-2-phenylindole (DAPI) solution (3 microg/ml in PBS). An area corresponding to central 14 degrees of the visual field was imaged. The nearest-neighbour distribution was determined for cells in both normal and glaucomatous RGCL. RESULTS Clustered RGC loss in human glaucoma was observed on a background of diffuse loss. The mean nearest-neighbour distance (NND) of the glaucomatous retinas was significantly higher than with controls (p<0.001). The distribution of NND in glaucomatous retinas was skewed to the higher values with a higher positive kurtosis relative to controls. The quantitative analysis of the pattern of cell loss is supported by the visual inspection of the patterns of cell loss. DISCUSSION The nearest-neighbour analysis is consistent with the presence of two patterns of cell loss in the RGCL in glaucoma. While the diffuse of cell loss can account for an overall reduction in the RGC population, an additional non-random pattern is consistent with the hypothesis that RGC loss has a local influence on the viability of surrounding cells.
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Affiliation(s)
- Y Lei
- School of Optometry and Vision Sciences, Cardiff University, Cardiff CF244LU, UK
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