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Chauhan P, Kho AM, Srinivasan VJ. From Soma to Synapse: Imaging Age-Related Rod Photoreceptor Changes in the Mouse with Visible Light OCT. OPHTHALMOLOGY SCIENCE 2023; 3:100321. [PMID: 37388138 PMCID: PMC10302163 DOI: 10.1016/j.xops.2023.100321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 04/05/2023] [Accepted: 04/24/2023] [Indexed: 07/01/2023]
Abstract
Purpose Although the outer nuclear layer (ONL) and outer plexiform layer (OPL) each exhibit a complex internal organization, near-infrared OCT depicts both as monolithic bands. Here, using visible light OCT in the C57BL/6J mouse retina, sublaminar age-related changes in photoreceptor features were imaged and interpreted. These features were (1) oscillations in reflectivity, or striations, in the ONL and (2) a moderately reflective subband in the OPL. Design Cross-sectional study. Participants Pigmented mice (C57BL/6J, n = 14). Methods A 1.0-μm axial resolution visible light spectral/Fourier domain OCT system was used for in vivo retinal imaging. Light and electron microscopy were performed ex vivo. Linear mixed effects models or regression were employed for statistical analysis. Main Outcome Measures Comparison of OCT subbands with corresponding histological features, as well as quantification of subband thickness and reflectivity. Results Corresponding histological comparisons confirm that striations in the ONL arise from the rowlike arrangement of photoreceptor nuclei and reveal that the moderately reflective OPL subband arises from rod spherules. Compression of outer ONL striations with age suggests changes in soma organization. Thinning of the moderately reflective OPL subband with age supports a reduction of synapses in the OPL. Critically, the ONL somas are tightly correlated with the purported spherule layer but not with the rest of the OPL. Conclusions Visible light OCT imaging of the mouse OPL resolves postsynaptic and synaptic differences. Visible light OCT can study rod photoreceptor changes from the soma to the synapse in the living mouse retina. Financial Disclosures Proprietary or commercial disclosure may be found after the references.
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Affiliation(s)
- Pooja Chauhan
- Department of Radiology, NYU Langone Health, New York, New York
| | - Aaron M. Kho
- Department of Biomedical Engineering, University of California Davis, Davis, California
| | - Vivek J. Srinivasan
- Department of Radiology, NYU Langone Health, New York, New York
- Department of Biomedical Engineering, University of California Davis, Davis, California
- Department of Ophthalmology, NYU Langone Health, New York, New York
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2
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Clemons MR, Dimico RH, Black C, Schlussler MK, Camerino MJ, Aldinger-Gibson K, Bartle A, Reynolds N, Eisenbrandt D, Rogers A, Andrianu J, Bruce B, Elliot A, Breazeal T, Griffin H, Murphy MK, Fuerst PG. The rod synapse in aging wildtype and Dscaml1 mutant mice. PLoS One 2023; 18:e0290257. [PMID: 37910517 PMCID: PMC10619811 DOI: 10.1371/journal.pone.0290257] [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] [Received: 02/08/2023] [Accepted: 08/03/2023] [Indexed: 11/03/2023] Open
Abstract
The retina is an intricately organized neural tissue built on cone and rod pathways for color and night vision. Genetic mutations that disrupt the proper function of the rod circuit contribute to blinding diseases including retinitis pigmentosa and congenital stationary night blindness (CSNB). Down Syndrome cell adhesion molecule like 1 (Dscaml1) is expressed by rods, rod bipolar cells (RBCs), and sub-populations of amacrine cells, and has been linked to a middle age onset of CSNB in humans. However, how Dscaml1 contributes to this visual deficit remains unexplored. Here, we probed Dscaml1's role in the maintenance of the rod-to-RBC synapse using a loss of function mouse model. We used immunohistochemistry to investigate the anatomical formation and maintenance of the rod-to-RBC synapse in the young, adult, and aging retina. We generated 3D reconstructions, using serial electron micrographs, of rod spherules and RBCs to measure the number of invaginating neurites, RBC dendritic tip number, and RBC mitochondrial morphology. We find that while rod-to-RBC synapses form and are maintained, similar to wildtype, that there is an increase in the number of invaginating neurites in rod spherules, a reduction in RBC dendritic tips, and reduced mitochondrial volume and complexity in the Dscaml1 mutant retina compared to controls. We also observed precocious sprouting of RBC dendrites into the outer nuclear layer (ONL) of the Dscaml1 mutant retina compared to controls. These results contribute to our knowledge of Dscaml1's role in rod circuit development and maintenance and give additional insight into possible genetic therapy targets for blinding diseases and disorders like CSNB.
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Affiliation(s)
- Mellisa R. Clemons
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Ren H. Dimico
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Cailyn Black
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Megan K. Schlussler
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Michael J. Camerino
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Kirah Aldinger-Gibson
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Amaris Bartle
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Nathan Reynolds
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Dylan Eisenbrandt
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Aspen Rogers
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - John Andrianu
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Bradley Bruce
- WWAMI Medical Education Program, University of Washington School of Medicine, Moscow, Idaho, United States of America
| | - Arthur Elliot
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Tom Breazeal
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Hannah Griffin
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Molly K. Murphy
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Peter G. Fuerst
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
- WWAMI Medical Education Program, University of Washington School of Medicine, Moscow, Idaho, United States of America
- Department of Biochemistry, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
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3
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Shrestha AP, Rameshkumar N, Boff JM, Rajmanna R, Chandrasegaran T, Frederick CE, Zenisek D, Vaithianathan T. The Effects of Aging on Rod Bipolar Cell Ribbon Synapses. Cells 2023; 12:2385. [PMID: 37830599 PMCID: PMC10572008 DOI: 10.3390/cells12192385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 09/20/2023] [Accepted: 09/27/2023] [Indexed: 10/14/2023] Open
Abstract
The global health concern posed by age-related visual impairment highlights the need for further research focused on the visual changes that occur during the process of aging. To date, multiple sensory alterations related to aging have been identified, including morphological and functional changes in inner hair cochlear cells, photoreceptors, and retinal ganglion cells. While some age-related morphological changes are known to occur in rod bipolar cells in the retina, their effects on these cells and on their connection to other cells via ribbon synapses remain elusive. To investigate the effects of aging on rod bipolar cells and their ribbon synapses, we compared synaptic calcium currents, calcium dynamics, and exocytosis in zebrafish (Danio rerio) that were middle-aged (MA,18 months) or old-aged (OA, 36 months). The bipolar cell terminal in OA zebrafish exhibited a two-fold reduction in number of synaptic ribbons, an increased ribbon length, and a decrease in local Ca2+ signals at the tested ribbon location, with little change in the overall magnitude of the calcium current or exocytosis in response to brief pulses. Staining of the synaptic ribbons with antibodies specific for PKCa revealed shortening of the inner nuclear and plexiform layers (INL and IPL). These findings shed light on age-related changes in the retina that are related to synaptic ribbons and calcium signals.
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Affiliation(s)
- Abhishek P. Shrestha
- Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Nirujan Rameshkumar
- Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Johane M. Boff
- Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Rhea Rajmanna
- Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | | | - Courtney E. Frederick
- Department of Molecular and Cellular Physiology, Yale University School of Medicine, New Haven, CT 06510, USA (D.Z.)
| | - David Zenisek
- Department of Molecular and Cellular Physiology, Yale University School of Medicine, New Haven, CT 06510, USA (D.Z.)
| | - Thirumalini Vaithianathan
- Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Department of Ophthalmology, Hamilton Eye Institute, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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4
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Mamidipaka A, Di Rosa I, Lee R, Zhu Y, Chen Y, Salowe R, Addis V, Sankar P, Daniel E, Ying GS, O’Brien JM. Factors Associated with Large Cup-to-Disc Ratio and Blindness in the Primary Open-Angle African American Glaucoma Genetics (POAAGG) Study. Genes (Basel) 2023; 14:1809. [PMID: 37761949 PMCID: PMC10530848 DOI: 10.3390/genes14091809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 09/14/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
BACKGROUND/AIMS Primary open-angle glaucoma (POAG) disproportionately affects individuals of African ancestry. In these patients' eyes, a large cup-to-disc ratio (LCDR > 0.90) suggests greater retinal ganglion cell loss, though these patients often display varied visual ability. This study investigated the prevalence and risk factors associated with LCDR in African ancestry individuals with POAG and explored the differences between blind (>20/200) and not blind (≤20/200) LCDR eyes. METHODS A case-control methodology was used to investigate the demographic, optic disc, and genetic risk factors of subjects in the Primary Open-Angle African American Glaucoma Genetics Study. Risk factors were analyzed using univariable and multivariable logistic regression models with inter-eye correlation adjusted using generalized estimating equations. RESULTS Out of 5605 eyes with POAG, 1440 eyes (25.7%) had LCDR. In the multivariable analysis, LCDR was associated with previous glaucoma surgery (OR = 1.72), increased intraocular pressure (OR = 1.04), decreased mean deviation (OR = 1.08), increased pattern standard deviation (OR = 1.06), thinner retinal nerve fiber layer (OR = 1.05), nasalization of vessels (OR = 2.67), bayonetting of vessels (OR = 1.98), visible pores in the lamina cribrosa (OR = 1.68), and a bean-shaped cup (OR = 2.11). Of LCDR eyes, 30.1% were classified as blind (≤20/200). In the multivariable analysis, the statistically significant risk factors of blindness in LCDR eyes were previous glaucoma surgery (OR = 1.72), increased intraocular pressure (OR = 1.05), decreased mean deviation (OR = 1.04), and decreased pattern standard deviation (OR = 0.90). CONCLUSIONS These findings underscore the importance of close monitoring of intraocular pressure and visual function in African ancestry POAG patients, particularly those with LCDR, to preserve visual function.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Joan M. O’Brien
- Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA 19104, USA; (A.M.); (I.D.R.); (R.L.); (Y.Z.); (Y.C.); (R.S.); (V.A.); (P.S.); (E.D.); (G.-S.Y.)
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5
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Van Hook MJ. Influences of Glaucoma on the Structure and Function of Synapses in the Visual System. Antioxid Redox Signal 2022; 37:842-861. [PMID: 35044228 PMCID: PMC9587776 DOI: 10.1089/ars.2021.0253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 12/31/2021] [Indexed: 11/12/2022]
Abstract
Significance: Glaucoma is an age-related neurodegenerative disorder of the visual system associated with sensitivity to intraocular pressure (IOP). It is the leading irreversible cause of vision loss worldwide, and vision loss results from damage and dysfunction of the retinal output neurons known as retinal ganglion cells (RGCs). Recent Advances: Elevated IOP and optic nerve injury triggers pruning of RGC dendrites, altered morphology of excitatory inputs from presynaptic bipolar cells, and disrupted RGC synaptic function. Less is known about RGC outputs, although evidence to date indicates that glaucoma is associated with altered mitochondrial and synaptic structure and function in RGC-projection targets in the brain. These early functional changes likely contribute to vision loss and might be a window into early diagnosis and treatment. Critical Issues: Glaucoma affects different RGC populations to varying extents and along distinct time courses. The influence of glaucoma on RGC synaptic function as well as the mechanisms underlying these effects remain to be determined. Since RGCs are an especially energetically demanding population of neurons, altered intracellular axon transport of mitochondria and mitochondrial function might contribute to RGC synaptic dysfunction in the retina and brain as well as RGC vulnerability in glaucoma. Future Directions: The mechanisms underlying differential RGC vulnerability remain to be determined. Moreover, the timing and mechanisms of RGCs synaptic dysfunction and degeneration will provide valuable insight into the disease process in glaucoma. Future work will be able to capitalize on these findings to better design diagnostic and therapeutic approaches to detect disease and prevent vision loss. Antioxid. Redox Signal. 37, 842-861.
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Affiliation(s)
- Matthew J. Van Hook
- Department of Ophthalmology & Visual Science and Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska, USA
- Department of Cellular & Integrative Physiology, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska, USA
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6
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Noailles A, Kutsyr O, Mayordomo-Febrer A, Lax P, López-Murcia M, Sanz-González SM, Pinazo-Durán MD, Cuenca N. Sodium Hyaluronate-Induced Ocular Hypertension in Rats Damages the Direction-Selective Circuit and Inner/Outer Retinal Plexiform Layers. Invest Ophthalmol Vis Sci 2022; 63:2. [PMID: 35503230 PMCID: PMC9078050 DOI: 10.1167/iovs.63.5.2] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Purpose To assess the changes in retinal morphology in a rat model of chronic glaucoma induced by ocular hypertension. Methods Intraocular pressure (IOP) was surgically increased through weekly injections of sodium hyaluronate (HYA) in the anterior eye chamber of the left eye of male Wistar rats, whereas the right eyes were sham operated (salt solution). During the 10-week experimental period, IOP was measured weekly with a rebound tonometer. Retinal cryosections were prepared for histological/immunohistochemical analysis and morphometry. Results IOP was higher in HYA-treated eyes than in sham-operated eyes along the 10-week period, which was significant from the fourth to the nineth week. Ocular hypertension in HYA-treated eyes was associated with morphologic and morphometric changes in bipolar cells, ON-OFF direction-selective ganglion cells, ON/OFF starburst amacrine cells, and inner plexiform layer sublamina. Conclusions Serial HYA treatment in the rat anterior eye chamber results in mild-to-moderate elevated and sustained IOP and ganglion cell death, which mimics most human open-angle glaucoma hallmarks. The reduced number of direction-selective ganglion cells and starburst amacrine cells accompanied by a deteriorated ON/OFF plexus in this glaucoma model could lend insight to the abnormalities in motion perception observed in patients with glaucoma.
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Affiliation(s)
- Agustina Noailles
- Physiology, Genetics and Microbiology, University of Alicante, Spain.,OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain
| | - Oksana Kutsyr
- Physiology, Genetics and Microbiology, University of Alicante, Spain.,OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain
| | - Aloma Mayordomo-Febrer
- Animal Medicine and Surgery, Faculty of Veterinary Medicine, Universidad CEU Cardenal Herrera, Valencia, Spain.,OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain.,Mixed Research Unit for Visual Health and Veterinary Ophthalmology CEU/FISABIO, Valencia, Spain
| | - Pedro Lax
- Physiology, Genetics and Microbiology, University of Alicante, Spain.,OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain
| | - María López-Murcia
- Animal Medicine and Surgery, Faculty of Veterinary Medicine, Universidad CEU Cardenal Herrera, Valencia, Spain.,Mixed Research Unit for Visual Health and Veterinary Ophthalmology CEU/FISABIO, Valencia, Spain
| | - Silvia M Sanz-González
- OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain.,Cellular and Molecular Ophthalmo-biology Research Group, Department of Surgery, University of Valencia, Valencia, Spain.,Ophthalmic Research Unit "Santiago Grisolía"/FISABIO, Valencia, Spain
| | - María Dolores Pinazo-Durán
- OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain.,Cellular and Molecular Ophthalmo-biology Research Group, Department of Surgery, University of Valencia, Valencia, Spain.,Ophthalmic Research Unit "Santiago Grisolía"/FISABIO, Valencia, Spain
| | - Nicolás Cuenca
- Physiology, Genetics and Microbiology, University of Alicante, Spain.,OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain
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7
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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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Pang JJ, Gao F, Wu SM. Generators of Pressure-Evoked Currents in Vertebrate Outer Retinal Neurons. Cells 2021; 10:cells10061288. [PMID: 34067375 PMCID: PMC8224636 DOI: 10.3390/cells10061288] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/13/2021] [Accepted: 05/19/2021] [Indexed: 12/19/2022] Open
Abstract
(1) Background: High-tension glaucoma damages the peripheral vision dominated by rods. How mechanosensitive channels (MSCs) in the outer retina mediate pressure responses is unclear. (2) Methods: Immunocytochemistry, patch clamp, and channel fluorescence were used to study MSCs in salamander photoreceptors. (3) Results: Immunoreactivity of transient receptor potential channel vanilloid 4 (TRPV4) was revealed in the outer plexiform layer, K+ channel TRAAK in the photoreceptor outer segment (OS), and TRPV2 in some rod OS disks. Pressure on the rod inner segment evoked sustained currents of three components: (A) the inward current at <-50 mV (Ipi), sensitive to Co2+; (B) leak outward current at ≥-80 mV (Ipo), sensitive to intracellular Cs+ and ruthenium red; and (C) cation current reversed at ~10 mV (Ipc). Hypotonicity induced slow currents like Ipc. Environmental pressure and light increased the FM 1-43-identified open MSCs in the OS membrane, while pressure on the OS with internal Cs+ closed a Ca2+-dependent current reversed at ~0 mV. Rod photocurrents were thermosensitive and affected by MSC blockers. (4) Conclusions: Rods possess depolarizing (TRPV) and hyperpolarizing (K+) MSCs, which mediate mutually compensating currents between -50 mV and 10 mV, serve as an electrical cushion to minimize the impact of ocular mechanical stress.
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Yuan X, Liu H, Li Y, Li W, Yu H, Shen X. Ribbon Synapses and Hearing Impairment in Mice After in utero Sevoflurane Exposure. DRUG DESIGN DEVELOPMENT AND THERAPY 2020; 14:2685-2693. [PMID: 32753847 PMCID: PMC7354911 DOI: 10.2147/dddt.s253031] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 06/18/2020] [Indexed: 12/12/2022]
Abstract
Introduction In utero, exposure to sevoflurane (a commonly used inhalation anesthetic) can lead to hearing impairment in offspring mice, but the underlying impairment mechanism is not known. Materials and Methods Day-15 pregnant mice were treated with 2.5% sevoflurane for 2 h to investigate sevoflurane ototoxicity. Cochleae from offspring mice were harvested for hair-cell and ribbon-synapse assessments. Hearing in offspring mice was assessed at postnatal day 30 using an auditory brainstem-response (ABR) test. Cochlear-explant cultures from offspring mice were exposed to 2.5% sevoflurane for 6 h. Immediately after treatment, explants were assessed for hair-cell morphology, mitochondrial oxidative stress, and autophagy. Results In utero, sevoflurane exposure impaired hearing in the offspring is demonstrated by a decrease in ABR wave I amplitudes, a marker for ribbon-synapse functionality. Sevoflurane exposure caused no obvious damage to hair cells, but cochlear ribbon synapses were reduced in postnatal day 15 offspring, and partially recovered by postnatal day 30. Sevoflurane treatment also increased mitochondrial reactive-oxygen species stress and decreased autophagy in the cochlear explants. Conclusion These results suggest that oxidative stress and reduced autophagy may underly ribbon-synapse involvement in sevoflurane-induced hearing loss.
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Affiliation(s)
- Xia Yuan
- Department of Anesthesiology, Shanghai Eye, Ear, Nose, and Throat Hospital, Fudan University, Shanghai 200031, People's Republic of China
| | - Hongjun Liu
- Department of Anesthesiology, Shanghai Eye, Ear, Nose, and Throat Hospital, Fudan University, Shanghai 200031, People's Republic of China
| | - Yufeng Li
- Department of Anesthesiology, Shanghai Eye, Ear, Nose, and Throat Hospital, Fudan University, Shanghai 200031, People's Republic of China
| | - Wen Li
- Research Center, Shanghai Eye, Ear, Nose, and Throat Hospital, Fudan University, Shanghai 200031, People's Republic of China
| | - Huiqian Yu
- Department of Otorhinolaryngology, Shanghai Eye, Ear, Nose, and Throat Hospital, Fudan University, Shanghai 200031, People's Republic of China
| | - Xia Shen
- Department of Anesthesiology, Shanghai Eye, Ear, Nose, and Throat Hospital, Fudan University, Shanghai 200031, People's Republic of China
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Forward genetic analysis using OCT screening identifies Sfxn3 mutations leading to progressive outer retinal degeneration in mice. Proc Natl Acad Sci U S A 2020; 117:12931-12942. [PMID: 32457148 DOI: 10.1073/pnas.1921224117] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Retinal disease and loss of vision can result from any disruption of the complex pathways controlling retinal development and homeostasis. Forward genetics provides an excellent tool to find, in an unbiased manner, genes that are essential to these processes. Using N-ethyl-N-nitrosourea mutagenesis in mice in combination with a screening protocol using optical coherence tomography (OCT) and automated meiotic mapping, we identified 11 mutations presumably causative of retinal phenotypes in genes previously known to be essential for retinal integrity. In addition, we found multiple statistically significant gene-phenotype associations that have not been reported previously and decided to target one of these genes, Sfxn3 (encoding sideroflexin-3), using CRISPR/Cas9 technology. We demonstrate, using OCT, light microscopy, and electroretinography, that two Sfxn3 -/- mouse lines developed progressive and severe outer retinal degeneration. Electron microscopy showed thinning of the retinal pigment epithelium and disruption of the external limiting membrane. Using single-cell RNA sequencing of retinal cells isolated from C57BL/6J mice, we demonstrate that Sfxn3 is expressed in several bipolar cell subtypes, retinal ganglion cells, and some amacrine cell subtypes but not significantly in Müller cells or photoreceptors. In situ hybridization confirmed these findings. Furthermore, pathway analysis suggests that Sfxn3 may be associated with synaptic homeostasis. Importantly, electron microscopy analysis showed disruption of synapses and synaptic ribbons in the outer plexiform layer of Sfxn3 -/- mice. Our work describes a previously unknown requirement for Sfxn3 in retinal function.
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11
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Macke EL, Henningsen E, Jessen E, Zumwalde NA, Landowski M, Western DE, Lee WH, Liu C, Gruenke NP, Doebley AL, Miller S, Pattnaik B, Ikeda S, Gumperz JE, Ikeda A. Loss of Chondroitin Sulfate Modification Causes Inflammation and Neurodegeneration in skt Mice. Genetics 2020; 214:121-134. [PMID: 31754016 PMCID: PMC6944401 DOI: 10.1534/genetics.119.302834] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 11/17/2019] [Indexed: 12/17/2022] Open
Abstract
One major aspect of the aging process is the onset of chronic, low-grade inflammation that is highly associated with age-related diseases. The molecular mechanisms that regulate these processes have not been fully elucidated. We have identified a spontaneous mutant mouse line, small with kinky tail (skt), that exhibits accelerated aging and age-related disease phenotypes including increased inflammation in the brain and retina, enhanced age-dependent retinal abnormalities including photoreceptor cell degeneration, neurodegeneration in the hippocampus, and reduced lifespan. By positional cloning, we identified a deletion in chondroitin sulfate synthase 1 (Chsy1) that is responsible for these phenotypes in skt mice. CHSY1 is a member of the chondroitin N-acetylgalactosaminyltransferase family that plays critical roles in the biosynthesis of chondroitin sulfate, a glycosaminoglycan (GAG) that is attached to the core protein to form the chondroitin sulfate proteoglycan (CSPG). Consistent with this function, the Chsy1 mutation dramatically decreases chondroitin sulfate GAGs in the retina and hippocampus. In addition, macrophage and neutrophil populations appear significantly altered in the bone marrow and spleen of skt mice, suggesting an important role for CHSY1 in the functioning of these immune cell types. Thus, our study reveals a previously unidentified impact of CHSY1 in the retina and hippocampus. Specifically, chondroitin sulfate (CS) modification of proteins by CHSY1 appears critical for proper regulation of immune cells of the myeloid lineage and for maintaining the integrity of neuronal tissues, since a defect in this gene results in increased inflammation and abnormal phenotypes associated with age-related diseases.
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Affiliation(s)
- Erica L Macke
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Erika Henningsen
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Erik Jessen
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
- Department of Biochemistry, University of Wisconsin-Madison, Wisconsin 53706
| | - Nicholas A Zumwalde
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Wisconsin 53706
| | - Michael Landowski
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Daniel E Western
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Wei-Hua Lee
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Che Liu
- Institute for Molecular Virology, University of Wisconsin-Madison, Wisconsin 53706
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Wisconsin 53706
| | - Nathan P Gruenke
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Anna-Lisa Doebley
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Samuel Miller
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
| | - Bikash Pattnaik
- Department of Pediatrics, University of Wisconsin-Madison, Wisconsin 53706
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Wisconsin 53706
- McPherson Eye Research Institute, University of Wisconsin-Madison, Wisconsin 53706
| | - Sakae Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
- McPherson Eye Research Institute, University of Wisconsin-Madison, Wisconsin 53706
| | - Jenny E Gumperz
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Wisconsin 53706
| | - Akihiro Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Wisconsin 53706
- McPherson Eye Research Institute, University of Wisconsin-Madison, Wisconsin 53706
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12
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Quantification of Changes in Visual Function During Disease Development in a Mouse Model of Pigmentary Glaucoma. J Glaucoma 2019; 27:828-841. [PMID: 30001268 DOI: 10.1097/ijg.0000000000001024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE We investigated the relationship between visual parameters that are commonly affected during glaucomatous disease progression with functional measures of retina physiology using electroretinography and behavioral measures of visual function in a mouse model of glaucoma. Electroretinogram components measuring retinal ganglion cell (RGC) responses were determined using the non-invasive Ganzfeld flash electroretinography (fERG) to assess RGC loss in a mouse model of glaucoma. METHODS Intraocular pressure (IOP), behaviorally assessed measures of visual function, namely visual acuity and contrast sensitivity as well as fERG responses were recorded in 4- and 11-month-old male DBA/2 mice. Scotopic threshold response (STR) and photopic negative response components as well as oscillatory potentials (OPs) were isolated from fERG responses and correlated with IOP, optomotor reflex measurements, and RGC counts. RESULTS The 11-month-old DBA/2 mice had significantly elevated IOP, reduced visual performance, as assessed behaviorally, significant RGC loss, deficits in standardized fERG responses, reduced STRs, and differences in OP amplitudes and latencies, when compared with 4-month-old mice of the same strain. STRs and OPs correlated with some visual and physiological parameters. In addition, elevated IOP and RGC loss correlated positively with measures of visual function, specifically with surrogate measures of RGC function derived from fERG. CONCLUSIONS Our data suggest that RGC function as well as interactions of RGCs with other retinal cell types is impaired during glaucoma. In addition, a later OP wavelet denoted as OP4 in this study was identified as a very reproducible indicator of loss of visual function in the glaucoma mouse model.
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Evangelho K, Mastronardi CA, de-la-Torre A. Experimental Models of Glaucoma: A Powerful Translational Tool for the Future Development of New Therapies for Glaucoma in Humans-A Review of the Literature. MEDICINA (KAUNAS, LITHUANIA) 2019; 55:E280. [PMID: 31212881 PMCID: PMC6630440 DOI: 10.3390/medicina55060280] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 06/04/2019] [Accepted: 06/04/2019] [Indexed: 12/18/2022]
Abstract
Glaucoma is a common complex disease that leads to irreversible blindness worldwide. Even though preclinical studies showed that lowering intraocular pressure (IOP) could prevent retinal ganglion cells loss, clinical evidence suggests that lessening IOP does not prevent glaucoma progression in all patients. Glaucoma is also becoming more prevalent in the elderly population, showing that age is a recognized major risk factor. Indeed, recent findings suggest that age-related tissue alterations contribute to the development of glaucoma and have encouraged exploration for new treatment approaches. In this review, we provide information on the most frequently used experimental models of glaucoma and describe their advantages and limitations. Additionally, we describe diverse animal models of glaucoma that can be potentially used in translational medicine and aid an efficient shift to the clinic. Experimental animal models have helped to understand the mechanisms of formation and evacuation of aqueous humor, and the maintenance of homeostasis of intra-ocular pressure. However, the transfer of pre-clinical results obtained from animal studies into clinical trials may be difficult since the type of study does not only depend on the type of therapy to be performed, but also on a series of factors observed both in the experimental period and the period of transfer to clinical application. Conclusions: Knowing the exact characteristics of each glaucoma experimental model could help to diminish inconveniences related to the process of the translation of results into clinical application in humans.
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Affiliation(s)
- Karine Evangelho
- Doctorado en Ciencias Biomédicas y Biológicas, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá,11121, Colombia.
| | - Claudio A Mastronardi
- Neuroscience Research Group (NeurUROS), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá, 11121, Colombia.
| | - Alejandra de-la-Torre
- Neuroscience Research Group (NeurUROS), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá, 11121, Colombia.
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14
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Smith MA, Plyler ES, Dengler-Crish CM, Meier J, Crish SD. Nodes of Ranvier in Glaucoma. Neuroscience 2018; 390:104-118. [PMID: 30149050 DOI: 10.1016/j.neuroscience.2018.08.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 08/15/2018] [Accepted: 08/17/2018] [Indexed: 01/13/2023]
Abstract
Retinal ganglion cell axons of the DBA/2J mouse model of glaucoma, a model characterized by extensive neuroinflammation, preserve synaptic contacts with their subcortical targets for a time after onset of anterograde axonal transport deficits, axon terminal hypertrophy, and cytoskeletal alterations. Though retrograde axonal transport is still evident in these axons, it is unknown if they retain their ability to transmit visual information to the brain. Using a combination of in vivo multiunit electrophysiology, neuronal tract tracing, multichannel immunofluorescence, and transmission electron microscopy, we report that eye-brain signaling deficits precede transport loss and axonal degeneration in the DBA/2J retinal projection. These deficits are accompanied by node of Ranvier pathology - consisting of increased node length and redistribution of the voltage-gated sodium channel Nav1.6 that parallel changes seen early in multiple sclerosis (MS) axonopathy. Further, with age, axon caliber and neurofilament density increase without corresponding changes in myelin thickness. In contrast to these findings in DBA/2J mice, node pathologies were not observed in the induced microbead occlusion model of glaucoma - a model that lacks pre-existing inflammation. After one week of systemic treatment with fingolimod, an immunosuppressant therapy for relapsing-remitting MS, DBA/2J mice showed a substantial reduction in node pathology and mild effects on axon morphology. These data suggest that neurophysiological deficits in the DBA/2J may be due to defects in intact axons and targeting node pathology may be a promising intervention for some types of glaucoma.
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Affiliation(s)
- M A Smith
- Northeast Ohio Medical University, Rootstown, OH 44272, United States
| | - E S Plyler
- Northeast Ohio Medical University, Rootstown, OH 44272, United States; Kent State Biomedical Sciences Graduate Program, United States
| | - C M Dengler-Crish
- Northeast Ohio Medical University, Rootstown, OH 44272, United States
| | - J Meier
- Northeast Ohio Medical University, Rootstown, OH 44272, United States
| | - S D Crish
- Northeast Ohio Medical University, Rootstown, OH 44272, United States.
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15
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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: 47] [Impact Index Per Article: 6.7] [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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16
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Williams PA, Tribble JR, Pepper KW, Cross SD, Morgan BP, Morgan JE, John SWM, Howell GR. Inhibition of the classical pathway of the complement cascade prevents early dendritic and synaptic degeneration in glaucoma. Mol Neurodegener 2016; 11:26. [PMID: 27048300 PMCID: PMC4822272 DOI: 10.1186/s13024-016-0091-6] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 03/23/2016] [Indexed: 12/13/2022] Open
Abstract
Background Glaucoma is a complex, multifactorial disease characterised by the loss of retinal ganglion cells and their axons leading to a decrease in visual function. The earliest events that damage retinal ganglion cells in glaucoma are currently unknown. Retinal ganglion cell death appears to be compartmentalised, with soma, dendrite and axon changes potentially occurring through different mechanisms. There is mounting evidence from other neurodegenerative diseases suggesting that neuronal dendrites undergo a prolonged period of atrophy, including the pruning of synapses, prior to cell loss. In addition, recent evidence has shown the role of the complement cascade in synaptic pruning in glaucoma and other diseases. Results Using a genetic (DBA/2J mouse) and an inducible (rat microbead) model of glaucoma we first demonstrate that there is loss of retinal ganglion cell synapses and dendrites at time points that precede axon or soma loss. We next determine the role of complement component 1 (C1) in early synaptic loss and dendritic atrophy during glaucoma. Using a genetic knockout of C1qa (D2.C1qa-/- mouse) or pharmacological inhibition of C1 (in the rat bead model) we show that inhibition of C1 is sufficient to preserve dendritic and synaptic architecture. Conclusions This study further supports assessing the potential for complement-modulating therapeutics for the prevention of retinal ganglion cell degeneration in glaucoma.
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Affiliation(s)
| | - James R Tribble
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, CF24 4HQ, UK
| | | | - Stephen D Cross
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, CF24 4HQ, UK
| | - B Paul Morgan
- Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, CF14 4XN, UK
| | - James E Morgan
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, CF24 4HQ, UK
| | - Simon W M John
- The Jackson Laboratory, Bar Harbor, ME, 04609, USA. .,Department of Ophthalmology, Tufts University of Medicine, Boston, MA, 02111, USA. .,The Howard Hughes Medical Institute, Bar Harbor, ME, 04609, USA.
| | - Gareth R Howell
- The Jackson Laboratory, Bar Harbor, ME, 04609, USA. .,Graduate Program in Genetics, Sackler School of Graduate Biomedical Sciences, Tufts University, 136 Harrison Avenue, Boston, MA, USA.
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17
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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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18
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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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19
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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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20
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Higuchi H, Macke EL, Lee WH, Miller SA, Xu JC, Ikeda S, Ikeda A. Genetic basis of age-dependent synaptic abnormalities in the retina. Mamm Genome 2014; 26:21-32. [PMID: 25273269 DOI: 10.1007/s00335-014-9546-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 09/01/2014] [Indexed: 12/17/2022]
Abstract
Understanding the normal aging process will help us determine the mechanisms of how age-related diseases are caused and progress. A/J inbred mice have been shown to exhibit accelerated aging phenotypes in the retina including increased inflammation and photoreceptor cell degeneration, which resemble human aging symptoms. C57BL/6J (B6) inbred mice are less susceptible for these abnormalities, indicating the existence of genetic factor(s) that affect their severity. In this study, we determined that another age-dependent phenotype, ectopic synapse formation, is also accelerated in the A/J retina compared to the B6 retina. Through genetic mapping utilizing recombinant inbred strains, we identified quantitative trait loci (QTLs) on chromosome 7 and 19, which contribute to abnormal retinal synapses as well as other age-dependent phenotypes. Using consomic single chromosome substitution lines where a single chromosome is from A/J and the rest of the genome is B6, we investigated the individual effect of each QTL on retinal aging phenotypes. We observed that both QTLs independently contribute to abnormal retinal synapses, reduction in the number of cone cells, and an up-regulation of retinal stress marker, glial fibrillary acidic protein (GFAP). Mice with a single chromosome substitution on chromosome 19 also exhibited an increase in inflammatory cells, which is characteristic of aging and age-related macular degeneration. Thus, we identified QTLs that are independently capable of affecting the severity and progression of age-dependent retinal abnormalities in mice.
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Affiliation(s)
- Hitoshi Higuchi
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, 53706, USA
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21
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Genové G, Mollick T, Johansson K. Photoreceptor degeneration, structural remodeling and glial activation: a morphological study on a genetic mouse model for pericyte deficiency. Neuroscience 2014; 279:269-84. [PMID: 25224828 DOI: 10.1016/j.neuroscience.2014.09.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Revised: 09/01/2014] [Accepted: 09/05/2014] [Indexed: 01/10/2023]
Abstract
Interaction between pericytes and endothelial cells via platelet-derived growth factor B (PDGF-B) signaling is critical for the development of the retinal microvasculature. The PDGF-B retention motif controls the spatial distribution range of the growth factor in the vicinity of its producing endothelial cells allowing its recognition by PDGF receptor beta-(PDGFR-β)-carrying pericytes; this promotes recruitment of pericytes to the vascular basement membrane. Impairment of the PDGF-B signaling mechanism causes development of vascular abnormalities, and in the retina this consequently leads to defects in the neurological circuitry. The vascular pathology in the pdgf-b(ret/ret) (PDGF-B retention motif knockout) mouse retina has been previously reported; our study investigates the progressive neuronal defects and changes in the retinal morphology of this pericyte-deficient mouse model. Immunohistochemical analysis revealed retinal injuries to occur as early as postnatal day (P) 10 with substantial damage progressing from P15 and onward. Vascular abnormalities were apparent from P10, however, prominent neuronal defects were mostly observed from P15, beginning with the compromised integrity of the laminated retinal structure characterized by the presence of rosettes and focally distorted regions. Photoreceptor degeneration was observed by loss of both rod and cone cells, including the disassembly and altered structure of their synaptic terminals. Significant shortening of cone outer segments was observed from P10 and later stages; however, decrease in cone density was only observed at P28. Disorganization and dendrite remodeling of rod bipolar cells also added to the diminished neural and synaptic integrity. Moreover, in response to retinal injuries, Müller and microglial cells were observed to be in the reactive phenotype from P15 and onward. Such a sequence of events indicates that the pdgf-b(ret/ret) mouse model displays a short time frame between P10 and P15, during which the retina shifts to a retinopathic phase by the development of prominently altered morphological features.
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Affiliation(s)
- G Genové
- Division of Vascular Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - T Mollick
- School of Health and Medicine, Örebro University, Örebro, Sweden
| | - K Johansson
- School of Health and Medicine, Örebro University, Örebro, Sweden.
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22
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Regus-Leidig H, Fuchs M, Löhner M, Leist SR, Leal-Ortiz S, Chiodo VA, Hauswirth WW, Garner CC, Brandstätter JH. In vivo knockdown of Piccolino disrupts presynaptic ribbon morphology in mouse photoreceptor synapses. Front Cell Neurosci 2014; 8:259. [PMID: 25232303 PMCID: PMC4153300 DOI: 10.3389/fncel.2014.00259] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 08/13/2014] [Indexed: 01/08/2023] Open
Abstract
Piccolo is the largest known cytomatrix protein at active zones of chemical synapses. A growing number of studies on conventional chemical synapses assign Piccolo a role in the recruitment and integration of molecules relevant for both endo- and exocytosis of synaptic vesicles, the dynamic assembly of presynaptic F-actin, as well as the proteostasis of presynaptic proteins, yet a direct function in the structural organization of the active zone has not been uncovered in part due to the expression of multiple alternatively spliced isoforms. We recently identified Piccolino, a Piccolo splice variant specifically expressed in sensory ribbon synapses of the eye and ear. Here we down regulated Piccolino in vivo via an adeno-associated virus-based RNA interference approach and explored the impact on the presynaptic structure of mouse photoreceptor ribbon synapses. Detailed immunocytochemical light and electron microscopical analysis of Piccolino knockdown in photoreceptors revealed a hitherto undescribed photoreceptor ribbon synaptic phenotype with striking morphological changes of synaptic ribbon ultrastructure.
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Affiliation(s)
- Hanna Regus-Leidig
- Department of Biology, Animal Physiology, Friedrich-Alexander-University of Erlangen-Nuremberg Erlangen, Germany
| | - Michaela Fuchs
- Department of Biology, Animal Physiology, Friedrich-Alexander-University of Erlangen-Nuremberg Erlangen, Germany
| | - Martina Löhner
- Department of Biology, Animal Physiology, Friedrich-Alexander-University of Erlangen-Nuremberg Erlangen, Germany
| | - Sarah R Leist
- Department of Biology, Animal Physiology, Friedrich-Alexander-University of Erlangen-Nuremberg Erlangen, Germany ; Department of Infection Genetics, Helmholtz Centre for Infection Research Braunschweig, Germany
| | - Sergio Leal-Ortiz
- Department of Psychiatry and Behavioral Sciences, Stanford University Palo Alto, CA, USA
| | - Vince A Chiodo
- Department of Ophthalmology, College of Medicine, University of Florida Gainesville, FL, USA
| | - William W Hauswirth
- Department of Ophthalmology, College of Medicine, University of Florida Gainesville, FL, USA
| | - Craig C Garner
- Department of Psychiatry and Behavioral Sciences, Stanford University Palo Alto, CA, USA ; Deutsches Zentrum für Neurodegenerative Erkrankungen Charité, Berlin, Germany
| | - Johann H Brandstätter
- Department of Biology, Animal Physiology, Friedrich-Alexander-University of Erlangen-Nuremberg Erlangen, Germany
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23
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D'Orazi FD, Suzuki SC, Wong RO. Neuronal remodeling in retinal circuit assembly, disassembly, and reassembly. Trends Neurosci 2014; 37:594-603. [PMID: 25156327 DOI: 10.1016/j.tins.2014.07.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 07/03/2014] [Accepted: 07/27/2014] [Indexed: 10/24/2022]
Abstract
Developing neuronal circuits often undergo a period of refinement to eliminate aberrant synaptic connections. Inappropriate connections can also form among surviving neurons during neuronal degeneration. The laminar organization of the vertebrate retina enables synaptic reorganization to be readily identified. Synaptic rearrangements are shown to help sculpt developing retinal circuits, although the mechanisms involved remain debated. Structural changes in retinal diseases can also lead to functional rewiring. This poses a major challenge to retinal repair because it may be necessary to untangle the miswired connections before reconnecting with proper synaptic partners. Here, we review our current understanding of the mechanisms that underlie circuit remodeling during retinal development, and discuss how alterations in connectivity during damage could impede circuit repair.
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Affiliation(s)
- Florence D D'Orazi
- Department of Biological Structure, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA
| | - Sachihiro C Suzuki
- Department of Biological Structure, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA
| | - Rachel O Wong
- Department of Biological Structure, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA.
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24
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Fernández-Sánchez L, de Sevilla Müller LP, Brecha NC, Cuenca N. Loss of outer retinal neurons and circuitry alterations in the DBA/2J mouse. Invest Ophthalmol Vis Sci 2014; 55:6059-72. [PMID: 25118265 DOI: 10.1167/iovs.14-14421] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
PURPOSE The DBA/2J mouse line develops essential iris atrophy, pigment dispersion, and glaucomatous age-related changes, including an increase of IOP, optic nerve atrophy, and retinal ganglion cell (RGC) death. The aim of this study was to evaluate possible morphological changes in the outer retina of the DBA/2J mouse concomitant with disease progression and aging, based on the reduction of both the a- and b-waves and photopic flicker ERGs in this mouse line. METHODS Vertically sectioned DBA/2J mice retinas were evaluated at 3, 8, and 16 months of age using photoreceptor, horizontal, and bipolar cell markers. Sixteen-month-old C57BL/6 mice retinas were used as controls. RESULTS The DBA/2J mice had outer retinal degeneration at all ages, with the most severe degeneration in the oldest retinas. At 3 months of age, the number of photoreceptor cells and the thickness of the OPL were reduced. In addition, there was a loss of horizontal and ON-bipolar cell processes. At 8 months of age, RGC degeneration occurred in patches, and in the outer retina overlying these patches, cone morphology was impaired with a reduction in size as well as loss of outer segments and growth of horizontal and bipolar cell processes into the outer nuclear layer. At 16 months of age, connectivity between photoreceptors and horizontal and bipolar cell processes overlying these patches was lost. CONCLUSIONS Retinal degeneration in DBA/2J mice includes photoreceptor death, loss of bipolar and horizontal cell processes, and loss of synaptic contacts in an aging-dependent manner.
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Affiliation(s)
- Laura Fernández-Sánchez
- Department of Physiology, Genetics, and Microbiology, University of Alicante, San Vicente del Raspeig, Spain
| | - Luis Pérez de Sevilla Müller
- Department of Neurobiology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California, United States
| | - Nicholas C Brecha
- Department of Neurobiology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California, United States
| | - Nicolás Cuenca
- Department of Physiology, Genetics, and Microbiology, University of Alicante, San Vicente del Raspeig, Spain
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25
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Cuenca N, Fernández-Sánchez L, Campello L, Maneu V, De la Villa P, Lax P, Pinilla I. Cellular responses following retinal injuries and therapeutic approaches for neurodegenerative diseases. Prog Retin Eye Res 2014; 43:17-75. [PMID: 25038518 DOI: 10.1016/j.preteyeres.2014.07.001] [Citation(s) in RCA: 296] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 07/03/2014] [Accepted: 07/07/2014] [Indexed: 01/17/2023]
Abstract
Retinal neurodegenerative diseases like age-related macular degeneration, glaucoma, diabetic retinopathy and retinitis pigmentosa each have a different etiology and pathogenesis. However, at the cellular and molecular level, the response to retinal injury is similar in all of them, and results in morphological and functional impairment of retinal cells. This retinal degeneration may be triggered by gene defects, increased intraocular pressure, high levels of blood glucose, other types of stress or aging, but they all frequently induce a set of cell signals that lead to well-established and similar morphological and functional changes, including controlled cell death and retinal remodeling. Interestingly, an inflammatory response, oxidative stress and activation of apoptotic pathways are common features in all these diseases. Furthermore, it is important to note the relevant role of glial cells, including astrocytes, Müller cells and microglia, because their response to injury is decisive for maintaining the health of the retina or its degeneration. Several therapeutic approaches have been developed to preserve retinal function or restore eyesight in pathological conditions. In this context, neuroprotective compounds, gene therapy, cell transplantation or artificial devices should be applied at the appropriate stage of retinal degeneration to obtain successful results. This review provides an overview of the common and distinctive features of retinal neurodegenerative diseases, including the molecular, anatomical and functional changes caused by the cellular response to damage, in order to establish appropriate treatments for these pathologies.
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Affiliation(s)
- Nicolás Cuenca
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain; Multidisciplinary Institute for Environmental Studies "Ramon Margalef", University of Alicante, Alicante, Spain.
| | - Laura Fernández-Sánchez
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Laura Campello
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Victoria Maneu
- Department of Optics, Pharmacology and Anatomy, University of Alicante, Alicante, Spain
| | - Pedro De la Villa
- Department of Systems Biology, University of Alcalá, Alcalá de Henares, Spain
| | - Pedro Lax
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Isabel Pinilla
- Department of Ophthalmology, Lozano Blesa University Hospital, Aragon Institute of Health Sciences, Zaragoza, Spain
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26
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Hoon M, Okawa H, Della Santina L, Wong ROL. Functional architecture of the retina: development and disease. Prog Retin Eye Res 2014; 42:44-84. [PMID: 24984227 DOI: 10.1016/j.preteyeres.2014.06.003] [Citation(s) in RCA: 327] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 06/08/2014] [Accepted: 06/22/2014] [Indexed: 12/22/2022]
Abstract
Structure and function are highly correlated in the vertebrate retina, a sensory tissue that is organized into cell layers with microcircuits working in parallel and together to encode visual information. All vertebrate retinas share a fundamental plan, comprising five major neuronal cell classes with cell body distributions and connectivity arranged in stereotypic patterns. Conserved features in retinal design have enabled detailed analysis and comparisons of structure, connectivity and function across species. Each species, however, can adopt structural and/or functional retinal specializations, implementing variations to the basic design in order to satisfy unique requirements in visual function. Recent advances in molecular tools, imaging and electrophysiological approaches have greatly facilitated identification of the cellular and molecular mechanisms that establish the fundamental organization of the retina and the specializations of its microcircuits during development. Here, we review advances in our understanding of how these mechanisms act to shape structure and function at the single cell level, to coordinate the assembly of cell populations, and to define their specific circuitry. We also highlight how structure is rearranged and function is disrupted in disease, and discuss current approaches to re-establish the intricate functional architecture of the retina.
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Affiliation(s)
- Mrinalini Hoon
- Department of Biological Structure, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA
| | - Haruhisa Okawa
- Department of Biological Structure, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA
| | - Luca Della Santina
- Department of Biological Structure, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA
| | - Rachel O L Wong
- Department of Biological Structure, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA.
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27
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Howell GR, Soto I, Ryan M, Graham LC, Smith RS, John SWM. Deficiency of complement component 5 ameliorates glaucoma in DBA/2J mice. J Neuroinflammation 2013; 10:76. [PMID: 23806181 PMCID: PMC3708765 DOI: 10.1186/1742-2094-10-76] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 06/12/2013] [Indexed: 01/08/2023] Open
Abstract
Background Glaucoma is an age-related neurodegenerative disorder involving the loss of retinal ganglion cells (RGCs), which results in blindness. Studies in animal models have shown that activation of inflammatory processes occurs early in the disease. In particular, the complement cascade is activated very early in DBA/2J mice, a widely used mouse model of glaucoma. A comprehensive analysis of the role of the complement cascade in DBA/2J glaucoma has not been possible because DBA/2J mice are naturally deficient in complement component 5 (C5, also known as hemolytic complement, Hc), a key mediator of the downstream processes of the complement cascade, including the formation of the membrane attack complex. Methods To assess the role of C5 in DBA/2J glaucoma, we backcrossed a functional C5 gene from strain C57BL/6J to strain DBA/2J for at least 10 generations. The prevalence and severity of glaucoma was evaluated using ocular examinations, IOP measurements, and assessments of optic nerve damage and RGC degeneration. To understand how C5 affects glaucoma, C5 expression was assessed in the retinas and optic nerves of C5-sufficient DBA/2J mice, using immunofluorescence. Results C5-sufficient DBA/2J mice developed a more severe glaucoma at an earlier age than standard DBA/2J mice, which are therefore protected by C5 deficiency. Components of the membrane attack complex were found to be deposited at sites of axonal injury in the optic nerve head and associated with RGC soma in the retina. Conclusion C5 plays an important role in glaucoma, with its deficiency lessening disease severity. These results highlight the importance of fully understanding the role of the complement cascade in neurodegenerative diseases. Inhibiting C5 may be beneficial as a therapy for human glaucoma.
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Affiliation(s)
- Gareth R Howell
- The Jackson Laboratory, 600 Main Street, Bar Harbor, Maine, USA.
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28
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Cochlear Inner Hair Cell Ribbon Synapse is the Primary Target of Ototoxic Aminoglycoside Stimuli. Mol Neurobiol 2013; 48:647-54. [DOI: 10.1007/s12035-013-8454-2] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Accepted: 04/02/2013] [Indexed: 11/26/2022]
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