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Righetti G, Kempf M, Kohl S, Wissinger B, Kühlewein L, Stingl K, Stingl K. S-cone contribution to oscillatory potentials in patients with blue cone monochromacy. Doc Ophthalmol 2024; 149:11-21. [PMID: 38871951 PMCID: PMC11236933 DOI: 10.1007/s10633-024-09981-y] [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: 03/28/2024] [Accepted: 06/06/2024] [Indexed: 06/15/2024]
Abstract
PURPOSE The aim of this exploratory study is to investigate the role of S-cones in oscillatory potentials (OPs) generation by individuals with blue-cone monochromacy (BCM), retaining S-cones, and achromatopsia (ACHM), lacking cone functions. METHODS This retrospective study analyzed data from 39 ACHM patients, 20 BCM patients, and 26 controls. Central foveal thickness was obtained using spectral-domain optical coherence tomography, while amplitude and implicit time (IT) of a- and b-waves were extracted from the ISCEV Standard dark-adapted 3 cd.s.m-2 full-field ERG (ffERG). Time-frequency analysis of the same measurement enabled the extraction of OPs, providing insights into the dynamic characteristics of the recorded signal. RESULTS Both ACHM and BCM groups showed a significant reduction (p < .00001) of a- and b-wave amplitudes and ITs as well as the power of the OPs compared to the control groups. The comparison between ACHM and BCM didn't show any statistically significant differences in the electrophysiological parameters. The analysis of covariance revealed significantly reduced central foveal thickness in the BCM group compared to ACHM and controls (p < .00001), and in ACHM compared to controls (p < .00001), after age correction and Tukey post-hoc analysis. CONCLUSIONS S-cones do not significantly influence OPs, and the decline in OPs' power is not solely due to a reduced a-wave. This suggests a complex non-linear network influenced by photoreceptor inputs. Morphological changes don't correlate directly with functional alterations, prompting further exploration of OPs' function and physiological role.
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Affiliation(s)
- Giulia Righetti
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, 72076, Tübingen, Germany.
| | - Melanie Kempf
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, 72076, Tübingen, Germany
- Center for Rare Eye Diseases, University of Tübingen, 72076, Tübingen, Germany
| | - Susanne Kohl
- Molecular Genetics Laboratory, Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, 72076, Tübingen, Germany
| | - Bernd Wissinger
- Molecular Genetics Laboratory, Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, 72076, Tübingen, Germany
| | - Laura Kühlewein
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, 72076, Tübingen, Germany
- Institute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Katarina Stingl
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, 72076, Tübingen, Germany
- Center for Rare Eye Diseases, University of Tübingen, 72076, Tübingen, Germany
| | - Krunoslav Stingl
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, 72076, Tübingen, Germany
- Center for Rare Eye Diseases, University of Tübingen, 72076, Tübingen, Germany
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Huston CA, Milan M, Vance ML, Bickel MA, Miller LR, Negri S, Hibbs C, Vaden H, Hayes L, Csiszar A, Ungvari Z, Yabluchanskiy A, Tarantini S, Conley SM. The effects of time restricted feeding on age-related changes in the mouse retina. Exp Gerontol 2024; 194:112510. [PMID: 38964431 DOI: 10.1016/j.exger.2024.112510] [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: 04/21/2024] [Revised: 06/12/2024] [Accepted: 07/01/2024] [Indexed: 07/06/2024]
Abstract
Dietary modifications such as caloric restriction (CR) and intermittent fasting (IF) have gained popularity due to their proven health benefits in aged populations. In time restricted feeding (TRF), a form of intermittent fasting, the amount of time for food intake is regulated without restricting the caloric intake. TRF is beneficial for the central nervous system to support brain health in the context of aging. Therefore, we here ask whether TRF also exerts beneficial effects in the aged retina. We compared aged mice (24 months) on a TRF paradigm (access to food for six hours per day) for either 6 or 12 months against young control mice (8 months) and aged control mice on an ad libitum diet. We examined changes in the retina at the functional (electroretinography), structural (histology and fluorescein angiograms) and molecular (gene expression) level. TRF treatment showed amelioration of age-related reductions in both scotopic and photopic b-wave amplitudes suggesting benefits for retinal interneuron signaling. TRF did not affect age-related signs of retinal inflammation or microglial activation at either the molecular or histological level. Our data indicate that TRF helps preserve some aspects of retinal function that are decreased with aging, adding to our understanding of the health benefits that altered feeding patterns may confer.
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Affiliation(s)
- Cade A Huston
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Madison Milan
- Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Neuroscience and Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Michaela L Vance
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Marisa A Bickel
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Lauren R Miller
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Sharon Negri
- Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Clara Hibbs
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Hannah Vaden
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Lindsay Hayes
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Anna Csiszar
- Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Neuroscience and Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine, Department of Public Health, Semmelweis University, Budapest, Hungary
| | - Zoltan Ungvari
- Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Neuroscience and Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; International Training Program in Geroscience, Doctoral School of Basic and Translational Medicine, Department of Public Health, Semmelweis University, Budapest, Hungary
| | - Andriy Yabluchanskiy
- Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Neuroscience and Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Stefano Tarantini
- Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Neuroscience and Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Hudson College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
| | - Shannon M Conley
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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Barboni MTS, Sustar Habjan M, Petrovic Pajic S, Hawlina M. Electroretinographic oscillatory potentials in Leber hereditary optic neuropathy. Doc Ophthalmol 2024; 148:133-143. [PMID: 38451375 PMCID: PMC11096212 DOI: 10.1007/s10633-024-09968-9] [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: 10/26/2023] [Accepted: 02/06/2024] [Indexed: 03/08/2024]
Abstract
PURPOSE Leber hereditary optic neuropathy (LHON) affects retinal ganglion cells causing severe vision loss. Pattern electroretinogram and photopic negative response (PhNR) of the light-adapted (LA) full-field electroretinogram (ERG) are typically affected in LHON. In the present study, we evaluated dark-adapted (DA) and LA oscillatory potentials (OPs) of the flash ERG in genetically characterized LHON patients to dissociate slow from fast components of the response. METHODS Seven adult patients (mean age = 28.4 ± 5.6) in whom genetic diagnosis confirmed LHON with mtDNA or nuclear DNAJC30 (arLHON) pathogenic variants were compared to 12 healthy volunteers (mean age = 35.0 ± 12.1). Full-field ERGs were recorded from both eyes. Offline digital filters at 50, 75 and 100 Hz low cutoff frequencies were applied to isolate high-frequency components from the original ERG signals. RESULTS ERG a-waves and b-waves were comparable between LHON patients and controls, while PhNR was significantly reduced (p = 0.009) in LHON patients compared to controls, as expected. OPs derived from DA signals (75 Hz low cutoff frequency) showed reduced peak amplitude for OP2 (p = 0.019). LA OP differences between LHON and controls became significant (OP2: p = 0.047, OP3: p = 0.039 and OP4: p = 0.013) when the 100 Hz low-cutoff frequency filter was applied. CONCLUSIONS Reduced OPs in LHON patients may represent disturbed neuronal interactions in the inner retina with preserved photoreceptoral (a-wave) to bipolar cell (b-wave) activation. Reduced DA OP2 and high-cutoff LA OP alterations may be further explored as functional measures to characterize LHON status and progression.
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Affiliation(s)
| | - Maja Sustar Habjan
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000, Ljubljana, Slovenia
| | - Sanja Petrovic Pajic
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000, Ljubljana, Slovenia
- Clinic for Eye Diseases, University Clinical Center of Serbia, Belgrade, Serbia
| | - Marko Hawlina
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000, Ljubljana, Slovenia.
- Medical Faculty, Department of Ophthalmology, University of Ljubljana, Grablovičeva 46, 1000, Ljubljana, Slovenia.
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Lam CHI, Zuo B, Chan HHL, Leung TW, Abokyi S, Catral KPC, Tse DYY. Coenzyme Q10 eyedrops conjugated with vitamin E TPGS alleviate neurodegeneration and mitochondrial dysfunction in the diabetic mouse retina. Front Cell Neurosci 2024; 18:1404987. [PMID: 38863499 PMCID: PMC11165046 DOI: 10.3389/fncel.2024.1404987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 05/09/2024] [Indexed: 06/13/2024] Open
Abstract
Diabetic retinopathy (DR) is a leading cause of blindness and vision impairment worldwide and represents one of the most common complications among diabetic patients. Current treatment modalities for DR, including laser photocoagulation, intravitreal injection of corticosteroid, and anti-vascular endothelial growth factor (VEGF) agents, target primarily vascular lesions. However, these approaches are invasive and have several limitations, such as potential loss of visual function, retinal scars and cataract formation, and increased risk of ocular hypertension, vitreous hemorrhage, retinal detachment, and intraocular inflammation. Recent studies have suggested mitochondrial dysfunction as a pivotal factor leading to both the vascular and neural damage in DR. Given that Coenzyme Q10 (CoQ10) is a proven mitochondrial stabilizer with antioxidative properties, this study investigated the effect of CoQ10 eyedrops [in conjunction with vitamin E d-α-tocopheryl poly(ethylene glycol) 1000 succinate (TPGS)] on DR-induced neurodegeneration using a type 2 diabetes mouse model (C57BLKsJ-db/db mice). Utilizing a comprehensive electroretinography protocol, supported by immunohistochemistry, our results revealed that topical application of CoQ10 eyedrops conjugated with vitamin E TPGS produced a neuroprotective effect against diabetic-induced neurodegeneration by preserving the function and histology of various retinal neural cell types. Compared to the control group, mice treated with CoQ10 exhibited thicker outer and inner nuclear layers, higher densities of photoreceptor, cone cell, and rod-bipolar cell dendritic boutons, and reduced glial reactivity and microglial cell density. Additionally, the CoQ10 treatment significantly alleviated retinal levels of MMP-9 and enhanced mitochondrial function. These findings provide further insight into the role of mitochondrial dysfunction in the development of DR and suggest CoQ10 eyedrops, conjugated with vitamin E TPGS, as a potential complementary therapy for DR-related neuropathy.
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Affiliation(s)
- Christie Hang-I Lam
- School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
- Centre for Eye and Vision Research Limited, Shatin, Hong Kong SAR, China
| | - Bing Zuo
- School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Henry Ho-Lung Chan
- School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
- Centre for Eye and Vision Research Limited, Shatin, Hong Kong SAR, China
| | - Tsz-Wing Leung
- School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Samuel Abokyi
- School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | | | - Dennis Yan-Yin Tse
- School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
- Centre for Eye and Vision Research Limited, Shatin, Hong Kong SAR, China
- Research Centre for SHARP Vision, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
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Carozza G, Zerti D, Tisi A, Ciancaglini M, Maccarrone M, Maccarone R. An overview of retinal light damage models for preclinical studies on age-related macular degeneration: identifying molecular hallmarks and therapeutic targets. Rev Neurosci 2024; 35:303-330. [PMID: 38153807 DOI: 10.1515/revneuro-2023-0130] [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: 10/21/2023] [Accepted: 11/19/2023] [Indexed: 12/30/2023]
Abstract
Age-related macular degeneration (AMD) is a complex, multifactorial disease leading to progressive and irreversible retinal degeneration, whose pathogenesis has not been fully elucidated yet. Due to the complexity and to the multiple features of the disease, many efforts have been made to develop animal models which faithfully reproduce the overall AMD hallmarks or that are able to mimic the different AMD stages. In this context, light damage (LD) rodent models of AMD represent a suitable and reliable approach to mimic the different AMD forms (dry, wet and geographic atrophy) while maintaining the time-dependent progression of the disease. In this review, we comprehensively reported how the LD paradigms reproduce the main features of human AMD. We discuss the capability of these models to broaden the knowledge in AMD research, with a focus on the mechanisms and the molecular hallmarks underlying the pathogenesis of the disease. We also critically revise the remaining challenges and future directions for the use of LD models.
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Affiliation(s)
- Giulia Carozza
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Darin Zerti
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Annamaria Tisi
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Marco Ciancaglini
- Department of Life, Health & Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Mauro Maccarrone
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy
- European Center for Brain Research (CERC)/Santa Lucia Foundation IRCCS, 00143 Rome, Italy
| | - Rita Maccarone
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy
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Tu Z, Degg C, Bach M, McLean R, Sheth V, Thomas MG, Yang S, Gottlob I, Proudlock FA. ERG Responses in Albinism, Idiopathic Infantile Nystagmus, and Controls. Invest Ophthalmol Vis Sci 2024; 65:11. [PMID: 38573619 PMCID: PMC10996992 DOI: 10.1167/iovs.65.4.11] [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: 08/01/2023] [Accepted: 03/04/2024] [Indexed: 04/05/2024] Open
Abstract
Purpose Our primary aim was to compare adult full-field ERG (ffERG) responses in albinism, idiopathic infantile nystagmus (IIN), and controls. A secondary aim was to investigate the effect of within-subject changes in nystagmus eye movements on ffERG responses. Methods Dilated Ganzfeld flash ffERG responses were recorded using DTL electrodes under conditions of dark (standard and dim flash) and light adaptation in 68 participants with albinism, 43 with IIN, and 24 controls. For the primary aim, the effect of group and age on ffERG responses was investigated. For the secondary aim, null region characteristics were determined using eye movements recorded prior to ffERG recordings. ffERG responses were recorded near and away from the null regions of 18 participants also measuring the success rate of recordings. Results For the primary aim, age-adjusted photopic a- and b-wave amplitudes were consistently smaller in IIN compared with controls (P < 0.0001), with responses in both groups decreasing with age. In contrast, photopic a-wave amplitudes increased with age in albinism (P = 0.0035). For the secondary aim, more intense nystagmus significantly reduced the success rate of measurable responses. Within-subject changes in nystagmus intensity generated small, borderline significant differences in photopic b-wave peak times and a-and b-wave amplitudes under scotopic conditions with standard flash. Conclusions Age-adjusted photopic ffERG responses are significantly reduced in IIN adding to the growing body of evidence of retinal abnormalities in IIN. Differences between photopic responses in albinism and controls depend on age. Success at obtaining ffERG responses could be improved by recording responses at the null region.
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Affiliation(s)
- Zhanhan Tu
- University of Leicester Ulverscroft Eye Unit, School of Psychology and Vision Sciences, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester, United Kingdom
| | - Christopher Degg
- Medical Physics and Clinical Engineering, Nottingham University Hospitals NHS Trust, United Kingdom
| | - Michael Bach
- Eye Center, Freiburg University, Killianstraße 5, Freiburg, Germany
| | - Rebecca McLean
- University of Leicester Ulverscroft Eye Unit, School of Psychology and Vision Sciences, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester, United Kingdom
| | - Viral Sheth
- University of Leicester Ulverscroft Eye Unit, School of Psychology and Vision Sciences, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester, United Kingdom
| | - Mervyn G. Thomas
- University of Leicester Ulverscroft Eye Unit, School of Psychology and Vision Sciences, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester, United Kingdom
| | - Shangqing Yang
- Gonville and Caius College, University of Cambridge, Cambridge, United Kingdom
| | - Irene Gottlob
- University of Leicester Ulverscroft Eye Unit, School of Psychology and Vision Sciences, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester, United Kingdom
- Cooper University Hospital, Camden, United States
| | - Frank A. Proudlock
- University of Leicester Ulverscroft Eye Unit, School of Psychology and Vision Sciences, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester, United Kingdom
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Mesnard CS, Hays CL, Townsend LE, Barta CL, Gurumurthy CB, Thoreson WB. SYNAPTOTAGMIN-9 IN MOUSE RETINA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.27.546758. [PMID: 37425946 PMCID: PMC10327071 DOI: 10.1101/2023.06.27.546758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Synaptotagmin-9 (Syt9) is a Ca2+ sensor mediating fast synaptic release expressed in various parts of the brain. The presence and role of Syt9 in retina is unknown. We found evidence for Syt9 expression throughout the retina and created mice to conditionally eliminate Syt9 in a cre-dependent manner. We crossed Syt9fl/fl mice with Rho-iCre, HRGP-Cre, and CMV-cre mice to generate mice in which Syt9 was eliminated from rods (rodSyt9CKO), cones (coneSyt9CKO), or whole animals (CMVSyt9). CMVSyt9 mice showed an increase in scotopic electroretinogram (ERG) b-waves evoked by bright flashes with no change in a-waves. Cone-driven photopic ERG b-waves were not significantly different in CMVSyt9 knockout mice and selective elimination of Syt9 from cones had no effect on ERGs. However, selective elimination from rods decreased scotopic and photopic b-waves as well as oscillatory potentials. These changes occurred only with bright flashes where cone responses contribute. Synaptic release was measured in individual rods by recording anion currents activated by glutamate binding to presynaptic glutamate transporters. Loss of Syt9 from rods had no effect on spontaneous or depolarization-evoked release. Our data show that Syt9 is acts at multiple sites in the retina and suggest that it may play a role in regulating transmission of cone signals by rods.
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Affiliation(s)
- Chris S. Mesnard
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68106, USA
- Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68106, USA
| | - Cassandra L. Hays
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68106, USA
- Department of Medical Education, Creighton University, Omaha, NE 68178
| | - Lou E. Townsend
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68106, USA
- Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68106, USA
| | - Cody L. Barta
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68106, USA
| | | | - Wallace B. Thoreson
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68106, USA
- Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68106, USA
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Han C, Zheng XX, Zhang WF. High altitude retinopathy: An overview and new insights. Travel Med Infect Dis 2024; 58:102689. [PMID: 38295966 DOI: 10.1016/j.tmaid.2024.102689] [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: 09/01/2023] [Revised: 12/30/2023] [Accepted: 01/15/2024] [Indexed: 02/04/2024]
Abstract
High altitude retinopathy (HAR) is a common ocular disorder that occurs on ascent to high altitude. There are many clinical symptoms, retinal vascular dilatation, retinal edema and hemorrhage are common. These usually do not or slightly affect vision; rarely, severe cases develop serious or permanent vision loss. At present, the research progress of HAR mainly focuses on hemodynamic changes, blood-retinal barrier damage, oxidative stress and inflammatory response. Although the related studies on HAR are limited, it shows that HAR still belongs to hypoxia, and hypobaric hypoxia plays an aggravating role in promoting the development of the disease. Various studies have demonstrated the correlation of HAR with acute mountain sickness (AMS) and high-altitude cerebral edema (HACE), so a deeper understanding of HAR is important. The slow ascent rates and ascent altitude are the key to preventing any altitude sickness. Research on traditional chinese medicine (TCM) and western medicine has been gradually carried out. Further exploration of the pathogenesis and prevention strategies of HAR will provide better guidance for doctors and high-altitude travelers.
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Affiliation(s)
- Cong Han
- Department of Ophthalmology, The Second Hospital & Clinical Medical School, Lanzhou University, Lanzhou, 730000, Gansu, PR China.
| | - Xing-Xing Zheng
- Department of Ophthalmology, The Second Hospital & Clinical Medical School, Lanzhou University, Lanzhou, 730000, Gansu, PR China.
| | - Wen-Fang Zhang
- Department of Ophthalmology, The Second Hospital & Clinical Medical School, Lanzhou University, Lanzhou, 730000, Gansu, PR China.
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Polli L, Bourguignon P, Rizzon N, Moulard M, Bisch M, Schwan R, Schwitzer T. Association between alcohol use and retinal dysfunctions in patients with alcohol use disorder: A window on GABA, glutamate, and dopamine modulations. J Psychiatr Res 2024; 170:348-354. [PMID: 38211458 DOI: 10.1016/j.jpsychires.2023.12.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 12/17/2023] [Accepted: 12/19/2023] [Indexed: 01/13/2024]
Abstract
BACKGROUND Alcohol is the most widely consumed addictive substance around the world and have deleterious effect on the central nervous system. Alcohol consumption affect the balance of certain neurotransmitters like GABA, glutamate and dopamine. The retina provides an easy means of investigating dysfunctions of synaptic transmission in the brain. The purpose of this study is to assess the impact of alcohol consumption on retinal function using pattern electroretinogram (PERG) and flash electroretinogram (fERG). METHODS We recorded PERG and fERG under scotopic and photopic condition in 20 patients with alcohol use disorder and 20 controls. Implicit time and amplitude of numerous parameters were evaluated: a- and b-waves for fERG, OP3 and OP4 for dark-adapted 3.0 oscillatory potentials fERG, P50 and N95 for PERG. RESULTS Patients with alcohol use disorder showed a significant increase in N95 implicit time without a significant change in the amplitudes of oscillatory potentials. CONCLUSION The results of our study reflect the impact of alcohol use on ganglion cell function and could highlight alterations in glutamatergic neurotransmission inside the retina. We believe that ERG could be used as an early marker of alcohol consumption.
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Affiliation(s)
- Ludovic Polli
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France; Faculté de Médecine, Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Pierre Bourguignon
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France
| | - Nicolas Rizzon
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France
| | - Marie Moulard
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France; Faculté de Médecine, Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Michael Bisch
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France; Faculté de Médecine, Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Raymund Schwan
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France; Faculté de Médecine, Université de Lorraine, Vandœuvre-lès-Nancy, France; Fondation FondaMental, 94000, Créteil, France
| | - Thomas Schwitzer
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France; Faculté de Médecine, Université de Lorraine, Vandœuvre-lès-Nancy, France; Fondation FondaMental, 94000, Créteil, France.
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Günter A, Belhadj S, Seeliger MW, Mühlfriedel R. The Mongolian gerbil as an advanced model to study cone system physiology. Front Cell Neurosci 2024; 18:1339282. [PMID: 38333056 PMCID: PMC10850313 DOI: 10.3389/fncel.2024.1339282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 01/02/2024] [Indexed: 02/10/2024] Open
Abstract
In this work, we introduce a diurnal rodent, the Mongolian gerbil (Meriones unguiculatus) (MG) as an alternative to study retinal cone system physiology and pathophysiology in mice. The cone system is of particular importance, as it provides high-acuity and color vision and its impairment in retinal disorders is thus especially disabling. Despite their nocturnal lifestyle, mice are currently the most popular animals to study cone-related diseases due to the high availability of genetically modified models. However, the potential for successful translation of any cone-related results is limited due to the substantial differences in retinal organization between mice and humans. Alternatively, there are diurnal rodents such as the MG with a higher retinal proportion of cones and a macula-like specialized region for improved visual resolution, the visual streak. The focus of this work was the evaluation of the MG's cone system functionality using full-field electroretinography (ERG), together with a morphological assessment of its retinal/visual streak organization via angiography, optical coherence tomography (OCT), and photoreceptor immunohistochemistry. We found that rod system responses in MGs were comparable or slightly inferior to mice, while in contrast, cone system responses were much larger, more sensitive, and also faster than those in the murine counterparts, and in addition, it was possible to record sizeable ON and OFF ERG components. Morphologically, MG cone photoreceptor opsins were evenly distributed throughout the retina, while mice show a dorsoventral M- and S-opsin gradient. Additionally, each cone expressed a single opsin, in contrast to the typical co-expression of opsins in mice. Particular attention was given to the visual streak region, featuring a higher density of cones, elongated cone and rod outer segments (OSs), and an increased thickness of the inner and outer retinal layers in comparison to peripheral regions. In summary, our data render the MG a supreme model to investigate cone system physiology, pathophysiology, and to validate potential therapeutic strategies in that context.
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Affiliation(s)
- Alexander Günter
- Division of Ocular Neurodegeneration, Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
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Keeley PW, Trod S, Gamboa BN, Coffey PJ, Reese BE. Nfia Is Critical for AII Amacrine Cell Production: Selective Bipolar Cell Dependencies and Diminished ERG. J Neurosci 2023; 43:8367-8384. [PMID: 37775301 PMCID: PMC10711738 DOI: 10.1523/jneurosci.1099-23.2023] [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: 06/13/2023] [Revised: 09/20/2023] [Accepted: 09/21/2023] [Indexed: 10/01/2023] Open
Abstract
The nuclear factor one (NFI) transcription factor genes Nfia, Nfib, and Nfix are all enriched in late-stage retinal progenitor cells, and their loss has been shown to retain these progenitors at the expense of later-generated retinal cell types. Whether they play any role in the specification of those later-generated fates is unknown, but the expression of one of these, Nfia, in a specific amacrine cell type may intimate such a role. Here, Nfia conditional knockout (Nfia-CKO) mice (both sexes) were assessed, finding a massive and largely selective absence of AII amacrine cells. There was, however, a partial reduction in type 2 cone bipolar cells (CBCs), being richly interconnected to AII cells. Counts of dying cells showed a significant increase in Nfia-CKO retinas at postnatal day (P)7, after AII cell numbers were already reduced but in advance of the loss of type 2 CBCs detected by P10. Those results suggest a role for Nfia in the specification of the AII amacrine cell fate and a dependency of the type 2 CBCs on them. Delaying the conditional loss of Nfia to the first postnatal week did not alter AII cell number nor differentiation, further suggesting that its role in AII cells is solely associated with their production. The physiological consequences of their loss were assessed using the ERG, finding the oscillatory potentials to be profoundly diminished. A slight reduction in the b-wave was also detected, attributed to an altered distribution of the terminals of rod bipolar cells, implicating a role of the AII amacrine cells in constraining their stratification.SIGNIFICANCE STATEMENT The transcription factor NFIA is shown to play a critical role in the specification of a single type of retinal amacrine cell, the AII cell. Using an Nfia-conditional knockout mouse to eliminate this population of retinal neurons, we demonstrate two selective bipolar cell dependencies on the AII cells; the terminals of rod bipolar cells become mis-stratified in the inner plexiform layer, and one type of cone bipolar cell undergoes enhanced cell death. The physiological consequence of this loss of the AII cells was also assessed, finding the cells to be a major contributor to the oscillatory potentials in the electroretinogram.
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Affiliation(s)
- Patrick W Keeley
- Neuroscience Research Institute, University of California, Santa Barbara, California 93106-5060
| | - Stephanie Trod
- Neuroscience Research Institute, University of California, Santa Barbara, California 93106-5060
| | - Bruno N Gamboa
- Neuroscience Research Institute, University of California, Santa Barbara, California 93106-5060
| | - Pete J Coffey
- Neuroscience Research Institute, University of California, Santa Barbara, California 93106-5060
| | - Benjamin E Reese
- Neuroscience Research Institute, University of California, Santa Barbara, California 93106-5060
- Department of Psychological and Brain Sciences, University of California, Santa Barbara, California 93106-5060
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12
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Wakeham CM, Shi Q, Ren G, Haley TL, Duvoisin RM, von Gersdorff H, Morgans CW. Trophoblast glycoprotein is required for efficient synaptic vesicle exocytosis from retinal rod bipolar cells. Front Cell Neurosci 2023; 17:1306006. [PMID: 38099150 PMCID: PMC10720453 DOI: 10.3389/fncel.2023.1306006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 11/02/2023] [Indexed: 12/17/2023] Open
Abstract
Introduction Rod bipolar cells (RBCs) faithfully transmit light-driven signals from rod photoreceptors in the outer retina to third order neurons in the inner retina. Recently, significant work has focused on the role of leucine-rich repeat (LRR) proteins in synaptic development and signal transduction at RBC synapses. We previously identified trophoblast glycoprotein (TPBG) as a novel transmembrane LRR protein localized to the dendrites and axon terminals of RBCs. Methods We examined the effects on RBC physiology and retinal processing of TPBG genetic knockout in mice using immunofluorescence and electron microscopy, electroretinogram recording, patch-clamp electrophysiology, and time-resolved membrane capacitance measurements. Results The scotopic electroretinogram showed a modest increase in the b-wave and a marked attenuation in oscillatory potentials in the TPBG knockout. No effect of TPBG knockout was observed on the RBC dendritic morphology, TRPM1 currents, or RBC excitability. Because scotopic oscillatory potentials primarily reflect RBC-driven rhythmic activity of the inner retina, we investigated the contribution of TPBG to downstream transmission from RBCs to third-order neurons. Using electron microscopy, we found shorter synaptic ribbons in TPBG knockout axon terminals in RBCs. Time-resolved capacitance measurements indicated that TPBG knockout reduces synaptic vesicle exocytosis and subsequent GABAergic reciprocal feedback without altering voltage-gated Ca2+ currents. Discussion TPBG is required for normal synaptic ribbon development and efficient neurotransmitter release from RBCs to downstream cells. Our results highlight a novel synaptic role for TPBG at RBC ribbon synapses and support further examination into the mechanisms by which TPBG regulates RBC physiology and circuit function.
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Affiliation(s)
- Colin M. Wakeham
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Qing Shi
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Gaoying Ren
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Tammie L. Haley
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Robert M. Duvoisin
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Henrique von Gersdorff
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
- Vollum Institute, Oregon Health and Science University, Portland, OR, United States
- Casey Eye Institute, Oregon Health and Science University, Portland, OR, United States
| | - Catherine W. Morgans
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
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Kim MH, Strazza P, Puthussery T, Gross OP, Taylor WR, von Gersdorff H. Functional maturation of the rod bipolar to AII-amacrine cell ribbon synapse in the mouse retina. Cell Rep 2023; 42:113440. [PMID: 37976158 DOI: 10.1016/j.celrep.2023.113440] [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: 10/09/2022] [Revised: 09/05/2023] [Accepted: 10/30/2023] [Indexed: 11/19/2023] Open
Abstract
Retinal ribbon synapses undergo functional changes after eye opening that remain uncharacterized. Using light-flash stimulation and paired patch-clamp recordings, we examined the maturation of the ribbon synapse between rod bipolar cells (RBCs) and AII-amacrine cells (AII-ACs) after eye opening (postnatal day 14) in the mouse retina at near physiological temperatures. We find that light-evoked excitatory postsynaptic currents (EPSCs) in AII-ACs exhibit a slow sustained component that increases in magnitude with advancing age, whereas a fast transient component remains unchanged. Similarly, paired recordings reveal a dual-component EPSC with a slower sustained component that increases during development, even though the miniature EPSC (mEPSC) amplitude and kinetics do not change significantly. We thus propose that the readily releasable pool of vesicles from RBCs increases after eye opening, and we estimate that a short light flash can evoke the release of ∼4,000 vesicles onto a single mature AII-AC.
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Affiliation(s)
- Mean-Hwan Kim
- The Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA; Allen Institute for Brain Science, Seattle, WA 98109, USA.
| | - Paulo Strazza
- The Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Teresa Puthussery
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA; Herbert Wertheim School of Optometry & Vision Science, Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Owen P Gross
- The Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA; Department of Physics, Reed College, Portland, OR 97202, USA
| | - W Rowland Taylor
- Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA; Herbert Wertheim School of Optometry & Vision Science, Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Henrique von Gersdorff
- The Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA; Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA.
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Pfeifer CW, Walsh JT, Santeford A, Lin JB, Beatty WL, Terao R, Liu YA, Hase K, Ruzycki PA, Apte RS. Dysregulated CD200-CD200R signaling in early diabetes modulates microglia-mediated retinopathy. Proc Natl Acad Sci U S A 2023; 120:e2308214120. [PMID: 37903272 PMCID: PMC10636339 DOI: 10.1073/pnas.2308214120] [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: 05/18/2023] [Accepted: 09/25/2023] [Indexed: 11/01/2023] Open
Abstract
Diabetic retinopathy (DR) is a neurovascular complication of diabetes. Recent investigations have suggested that early degeneration of the neuroretina may occur prior to the appearance of microvascular changes; however, the mechanisms underlying this neurodegeneration have been elusive. Microglia are the predominant resident immune cell in the retina and adopt dynamic roles in disease. Here, we show that ablation of retinal microglia ameliorates visual dysfunction and neurodegeneration in a type I diabetes mouse model. We also provide evidence of enhanced microglial contact and engulfment of amacrine cells, ultrastructural modifications, and transcriptome changes that drive inflammation and phagocytosis. We show that CD200-CD200R signaling between amacrine cells and microglia is dysregulated during early DR and that targeting CD200R can attenuate high glucose-induced inflammation and phagocytosis in cultured microglia. Last, we demonstrate that targeting CD200R in vivo can prevent visual dysfunction, microglia activation, and retinal inflammation in the diabetic mouse. These studies provide a molecular framework for the pivotal role that microglia play in early DR pathogenesis and identify a potential immunotherapeutic target for treating DR in patients.
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Affiliation(s)
- Charles W. Pfeifer
- John F. Hardesty, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO63110
- Neurosciences Graduate Program, Roy and Diana Vagelos Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO63110
| | - James T. Walsh
- John F. Hardesty, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO63110
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO63110
| | - Andrea Santeford
- John F. Hardesty, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO63110
| | - Joseph B. Lin
- John F. Hardesty, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO63110
- Neurosciences Graduate Program, Roy and Diana Vagelos Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO63110
| | - Wandy L. Beatty
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO63110
| | - Ryo Terao
- John F. Hardesty, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO63110
- Department of Ophthalmology, Graduate School of Medicine, The University of Tokyo, Tokyo1138665, Japan
| | - Yizhou A. Liu
- John F. Hardesty, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO63110
| | - Keitaro Hase
- John F. Hardesty, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO63110
| | - Philip A. Ruzycki
- John F. Hardesty, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO63110
- Department of Genetics, Washington University School of Medicine, St. Louis, MO63110
| | - Rajendra S. Apte
- John F. Hardesty, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO63110
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO63110
- Department of Medicine, Washington University School of Medicine, St. Louis, MO63110
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15
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Amato R, Melecchi A, Pucci L, Canovai A, Marracci S, Cammalleri M, Dal Monte M, Caddeo C, Casini G. Liposome-Mediated Delivery Improves the Efficacy of Lisosan G against Retinopathy in Diabetic Mice. Cells 2023; 12:2448. [PMID: 37887292 PMCID: PMC10605070 DOI: 10.3390/cells12202448] [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: 09/25/2023] [Revised: 10/04/2023] [Accepted: 10/12/2023] [Indexed: 10/28/2023] Open
Abstract
Nutraceuticals are natural substances whose anti-oxidant and anti-inflammatory properties may be used to treat retinal pathologies. Their efficacy is limited by poor bioavailability, which could be improved using nanocarriers. Lisosan G (LG), a fermented powder from whole grains, protects the retina from diabetic retinopathy (DR)-induced damage. For this study, we tested whether the encapsulation of LG in liposomes (LipoLG) may increase its protective effects. Diabetes was induced in mice via streptozotocin administration, and the mice were allowed to freely drink water or a water dispersion of two different doses of LG or of LipoLG. Electroretinographic recordings after 6 weeks showed that only the highest dose of LG could partially protect the retina from diabetes-induced functional deficits, while both doses of LipoLG were effective. An evaluation of molecular markers of oxidative stress, inflammation, apoptosis, vascular endothelial growth factor, and the blood-retinal barrier confirmed that the highest dose of LG only partially protected the retina from DR-induced changes, while virtually complete prevention was obtained with either dose of LipoLG. These data indicate that the efficacy of LG in contrasting DR is greatly enhanced by its encapsulation in liposomes and may lay the ground for new dietary supplements with improved therapeutic effects against DR.
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Affiliation(s)
- Rosario Amato
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
| | - Alberto Melecchi
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
| | - Laura Pucci
- Institute of Agricultural Biology and Biotechnology, National Research Council (CNR), 56124 Pisa, Italy;
| | - Alessio Canovai
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
| | - Silvia Marracci
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
| | - Maurizio Cammalleri
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
- Interdepartmental Research Center Nutrafood “Nutraceuticals and Food for Health”, University of Pisa, 56124 Pisa, Italy
| | - Massimo Dal Monte
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
- Interdepartmental Research Center Nutrafood “Nutraceuticals and Food for Health”, University of Pisa, 56124 Pisa, Italy
| | - Carla Caddeo
- Department of Life and Environmental Sciences, University of Cagliari, 09042 Cagliari, Italy
| | - Giovanni Casini
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
- Interdepartmental Research Center Nutrafood “Nutraceuticals and Food for Health”, University of Pisa, 56124 Pisa, Italy
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Kanzaki Y, Matoba R, Kimura S, Hosokawa MM, Shiode Y, Doi S, Morita T, Kanzaki S, Takasu I, Tanikawa A, Morizane Y. Epiretinal Membrane Impairs the Inner Retinal Layer in a Traction Force-Dependent Manner. OPHTHALMOLOGY SCIENCE 2023; 3:100312. [PMID: 37214764 PMCID: PMC10199250 DOI: 10.1016/j.xops.2023.100312] [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: 01/04/2023] [Revised: 04/07/2023] [Accepted: 04/07/2023] [Indexed: 05/24/2023]
Abstract
Purpose To investigate the relationship between retinal traction force and impairment of the inner retinal layer in patients with epiretinal membrane (ERM). Design Nonrandomized, retrospective consecutive case series. Participants Two hundred nine eyes of 201 patients with idiopathic ERM who underwent vitrectomy for idiopathic ERM were enrolled. Methods Retinal folds caused by ERM were visualized using en face OCT, and the maximum depth of retinal folds within the parafovea (MDRF) was measured. Focal macular electroretinogram (ERG) was used to measure the amplitude and implicit time of each component for the ERM eyes and the normal fellow eyes. B-scan OCT images were used to measure the thicknesses of the inner nuclear layer (INL) and outer nuclear layer (ONL) + outer plexiform layer (OPL). Expression of α-smooth muscle actin (α-SMA) in surgically removed ERM specimens was quantified by reverse-transcription polymerase chain reaction. Main Outcome Measures We analyzed the relationship between MDRF and the relative amplitudes of focal macular ERG (affected eye/fellow eye), the relationships between MDRF and the mean INL thickness and ONL+OPL thickness, comparison of INL thickness and ONL+OPL thickness for each area when cases were classified according to MDRF localization in the ETDRS chart, and the relationship between MDRF and the relative expression of α-SMA in the ERM specimens. Results The MDRF significantly correlated with the relative amplitudes (affected eye/fellow eye) of b-waves and oscillatory potentials (r = -0.657, P = 0.015; r = -0.569, P = 0.042, respectively) and the mean INL thickness and ONL+OPL thickness (r = 0.604, P < 0.001; r = 0.210, P = 0.007, respectively). However, only the INL thickness progression rate was significantly correlated with the MDRF progression rate (r = 0.770, P < 0.001). On case stratification by localization of MDRF based on the ETDRS chart, in regions other than temporal regions, the INL thickness was significantly greater in regions with MDRF than in other regions. The MDRF significantly correlated with α-SMA expression in the ERM specimens (r = 0.555, P = 0.009). Conclusions The findings suggest that ERM impairs the inner retinal layer in a traction force-dependent manner. Financial Disclosures The author(s) have no proprietary or commercial interest in any materials discussed in this article.
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Affiliation(s)
- Yuki Kanzaki
- Department of Ophthalmology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan
| | - Ryo Matoba
- Department of Ophthalmology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan
| | - Shuhei Kimura
- Department of Ophthalmology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan
| | - Mio M. Hosokawa
- Department of Ophthalmology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan
| | - Yusuke Shiode
- Department of Ophthalmology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan
| | - Shinichiro Doi
- Department of Ophthalmology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan
| | - Tetsuro Morita
- Department of Ophthalmology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan
| | - Sayumi Kanzaki
- Department of Ophthalmology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan
| | | | - Atsuhiro Tanikawa
- Department of Ophthalmology, Fujita Health University Bantane Hospital, Nagoya City, Aichi, Japan
| | - Yuki Morizane
- Department of Ophthalmology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama City, Okayama, Japan
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Wei X, Li H, Zhu T, Yao F, Sui R. FDXR-associated disease in a Chinese cohort: Unraveling expanded ocular phenotypes and genetic spectrum. Exp Eye Res 2023; 234:109600. [PMID: 37481223 DOI: 10.1016/j.exer.2023.109600] [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: 05/31/2023] [Revised: 07/06/2023] [Accepted: 07/19/2023] [Indexed: 07/24/2023]
Abstract
FDXR: associated disease is characterized by optic atrophy, acoustic neuropathy, and developmental delays. This study evaluated the ocular phenotypes and genetic features of patients with biallelic FDXR variants. Five individuals from unrelated non-consanguineous Chinese families with biallelic FDXR variants were identified using whole exome sequencing, Sanger sequencing, and co-segregation validation. In addition to optic atrophy and diverse extraocular manifestations, all patients presented with retinal dystrophy, and electroretinogram showed severely impaired cone and rod functions in their first decades. Three of the five patients showed attenuated retinal vessels that appeared as white lines on the fundus, and fundus fluorescein angiography (FFA) further revealed vascular abnormalities including delayed filling, completely occluded retinal vasculature, and severe retinal vascular nonperfusion of the peripheral retina. Five novel FDXR variants were identified: c.383C > T (p.A128V), c.963delG (p.R322fs*7), c.1052_1053delTC (p.L351Pfs*12), c.394-11T > G and c.1002+1G > A. Retinal dystrophy with attenuated retinal vessels appearing as white lines was observed in this cohort, and the FFA images revealed that retinal vascular occlusion could be a distinct clinical characteristic of FDXR-associated disease. Probands with FDXR revealed severe early onset ophthalmic features with rapid-progression, indicating the importance of early diagnosis and treatment. Moreover, this is the first study to report FFA manifestations in an FDXR cohort, expanding the FDXR-associated ocular disease phenotype and genetic spectrum.
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Affiliation(s)
- Xing Wei
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Hui Li
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Tian Zhu
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Fengxia Yao
- Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Ruifang Sui
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China.
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Lam CHI, Zou B, Chan HHL, Tse DYY. Functional and structural changes in the neuroretina are accompanied by mitochondrial dysfunction in a type 2 diabetic mouse model. EYE AND VISION (LONDON, ENGLAND) 2023; 10:37. [PMID: 37653465 PMCID: PMC10472703 DOI: 10.1186/s40662-023-00353-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 07/16/2023] [Indexed: 09/02/2023]
Abstract
BACKGROUND Diabetic retinopathy (DR), one of the leading causes of blindness and vision impairment, is suggested to exhibit functional and structural changes in retinal neurons as the earliest manifestation, which could be used to predict the progression of related angiopathy. While neural function and survival rely on proper mitochondrial function, and a growing body of literature has supported the role of mitochondrial dysfunction in the development of DR, how diabetes affects mitochondrial function in retinal tissue remains elusive. This study primarily aimed to investigate mitochondrial functional changes in a diabetic rodent model. We also characterized the early DR phenotype, in particular, neurodegeneration. METHODS C57BLKsJ-db/db (db/db) mice (a type 2 diabetic mouse model) were used with their normoglycemic heterozygous littermates (db/+) serving as controls. Longitudinal changes in retinal function and morphology were assessed with electroretinography (ERG) and optical coherence tomography (OCT), respectively, at 9, 13, 17, and 25 weeks of age. At 25 weeks, the retinas were harvested for immunohistochemistry and ex vivo mitochondrial bioenergetics. RESULTS Decreased ERG responses were observed in db/db mice as early as 13 weeks of age. OCT revealed that db/db mice had significantly thinner retinas than the controls. Immunohistochemistry showed that the retinas of the db/db mice at 25 weeks were thinner at the outer and inner nuclear layers, with lower photoreceptor and cone cell densities compared with the db/+ mice. The number of rod-bipolar cell dendritic boutons and axon terminals was significantly reduced in db/db mice relative to the db/+ mice, suggesting that diabetes may lead to compromised synaptic connectivity. More importantly, the retinas of db/db mice had weaker mitochondrial functions than the controls. CONCLUSIONS Our longitudinal data suggest that diabetes-induced functional deterioration and morphological changes were accompanied by reduced mitochondrial function in the retina of db/db mice. These findings suggest that mitochondrial dysfunction may be a contributing factor triggering the development of DR. While the underlying mechanistic cause remains elusive, the db/db mice could be a useful animal model for testing potential treatment regimens targeting neurodegeneration in DR.
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Affiliation(s)
- Christie Hang-I Lam
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, SAR, China
- Centre for Eye and Vision Research Limited (CEVR), Hong Kong, SAR, China
| | - Bing Zou
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, SAR, China
| | - Henry Ho-Lung Chan
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, SAR, China
- Centre for Eye and Vision Research Limited (CEVR), Hong Kong, SAR, China
| | - Dennis Yan-Yin Tse
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, SAR, China.
- Centre for Eye and Vision Research Limited (CEVR), Hong Kong, SAR, China.
- Research Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, SAR, China.
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19
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Constable PA, Lim JKH, Thompson DA. Retinal electrophysiology in central nervous system disorders. A review of human and mouse studies. Front Neurosci 2023; 17:1215097. [PMID: 37600004 PMCID: PMC10433210 DOI: 10.3389/fnins.2023.1215097] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 07/17/2023] [Indexed: 08/22/2023] Open
Abstract
The retina and brain share similar neurochemistry and neurodevelopmental origins, with the retina, often viewed as a "window to the brain." With retinal measures of structure and function becoming easier to obtain in clinical populations there is a growing interest in using retinal findings as potential biomarkers for disorders affecting the central nervous system. Functional retinal biomarkers, such as the electroretinogram, show promise in neurological disorders, despite having limitations imposed by the existence of overlapping genetic markers, clinical traits or the effects of medications that may reduce their specificity in some conditions. This narrative review summarizes the principal functional retinal findings in central nervous system disorders and related mouse models and provides a background to the main excitatory and inhibitory retinal neurotransmitters that have been implicated to explain the visual electrophysiological findings. These changes in retinal neurochemistry may contribute to our understanding of these conditions based on the findings of retinal electrophysiological tests such as the flash, pattern, multifocal electroretinograms, and electro-oculogram. It is likely that future applications of signal analysis and machine learning algorithms will offer new insights into the pathophysiology, classification, and progression of these clinical disorders including autism, attention deficit/hyperactivity disorder, bipolar disorder, schizophrenia, depression, Parkinson's, and Alzheimer's disease. New clinical applications of visual electrophysiology to this field may lead to earlier, more accurate diagnoses and better targeted therapeutic interventions benefiting individual patients and clinicians managing these individuals and their families.
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Affiliation(s)
- Paul A. Constable
- College of Nursing and Health Sciences, Caring Futures Institute, Flinders University, Adelaide, SA, Australia
| | - Jeremiah K. H. Lim
- Discipline of Optometry, School of Allied Health, University of Western Australia, Perth, WA, Australia
| | - Dorothy A. Thompson
- The Tony Kriss Visual Electrophysiology Unit, Clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom
- UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
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20
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Curran ALK, Stukin J, Ambrosio L, Mantagos IS, Wu C, Vanderveen DK, Hansen RM, Akula JD, Fulton AB. Electroretinographic Responses in Retinopathy of Prematurity Treated Using Intravitreal Bevacizumab or Laser. Am J Ophthalmol 2023; 252:275-285. [PMID: 37146743 PMCID: PMC10524994 DOI: 10.1016/j.ajo.2023.04.014] [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: 10/24/2022] [Revised: 04/22/2023] [Accepted: 04/24/2023] [Indexed: 05/07/2023]
Abstract
PURPOSE Intravitreal injection of bevacizumab (IVB) offers advantages over laser photoablation for treatment of type 1 retinopathy of prematurity (ROP). However, retinal function has not, to date, been quantitatively compared following these interventions. Therefore, electroretinography (ERG) was used compare retinal function among eyes treated using IVB or laser, and control eyes. In addition, among the IVB-treated eyes, ERG was used to compare function in individuals in whom subsequent laser was and was not required. DESIGN Prospective clinical cohort study. METHODS ERG was used to record dark- and light-adapted stimulus/response functions in 21 children treated using IVB (12 of whom required subsequent laser in at least 1 eye for persistent avascular retina [PAR]). Sensitivity and amplitude parameters were derived from the a-wave, b-wave, and oscillatory potentials (OPs), representing activity in photoreceptor, postreceptor, and inner retinal cells, respectively. These parameters were then referenced to those of 76 healthy, term-born controls and compared to those of 10 children treated using laser only. RESULTS In children with treated ROP, every ERG parameter was significantly below the mean in controls. However, these significant ERG deficits did not differ between IVB- and laser-treated eyes. Among children treated using IVB, no ERG parameter was significantly associated with dose or need for subsequent laser. CONCLUSION Retinal function was significantly impaired in treated ROP eyes. Function in IVB-treated eyes did not differ from that in laser-treated eyes. Functional differences also did not distinguish those IVB-treated eyes that would subsequently need laser for PAR.
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Affiliation(s)
| | - Justyna Stukin
- Boston Children’s Hospital, Ophthalmology
- Northeastern University, Behavioral Neuroscience
| | - Lucia Ambrosio
- University of Naples Federico II, Department of Neuroscience, Reproductive and Odontostomatological Sciences
- University of Naples Federico II, Department of Public Health
| | - Iason S. Mantagos
- Boston Children’s Hospital, Ophthalmology
- Harvard Medical School, Ophthalmology
| | - Carolyn Wu
- Boston Children’s Hospital, Ophthalmology
- Harvard Medical School, Ophthalmology
| | | | - Ronald M. Hansen
- Boston Children’s Hospital, Ophthalmology
- Harvard Medical School, Ophthalmology
| | - James D. Akula
- Boston Children’s Hospital, Ophthalmology
- Harvard Medical School, Ophthalmology
| | - Anne B. Fulton
- Boston Children’s Hospital, Ophthalmology
- Harvard Medical School, Ophthalmology
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21
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Haq W, Zrenner E, Ueffing M, Paquet-Durand F. Using Micro-Electrode-Array Recordings and Retinal Disease Models to Elucidate Visual Functions: Simultaneous Recording of Local Electroretinograms and Ganglion Cell Action Potentials Reveals the Origin of Retinal Oscillatory Potentials. Bioengineering (Basel) 2023; 10:725. [PMID: 37370656 DOI: 10.3390/bioengineering10060725] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/08/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
BACKGROUND The electroretinogram (ERG) is an essential diagnostic tool for visual function, both in clinical and research settings. Here, we establish an advanced in vitro approach to assess cell-type-specific ERG signal components. METHODS Retinal explant cultures, maintained under entirely controlled conditions, were derived from wild-type mice and rd10 rod- and cpfl1 cone-degeneration mouse models. Local micro-ERG (µERG) and simultaneous ganglion cell (GC) recordings were obtained from the retinal explants using multi-electrode arrays. Band-pass filtering was employed to distinguish photoreceptor, bipolar cell, amacrine cell (AC), and GC responses. RESULTS Scotopic and photopic stimulation discriminated between rod and cone responses in wild-type and mutant retina. The 25 kHz sampling rate allowed the visualization of oscillatory potentials (OPs) in extraordinary detail, revealing temporal correlations between OPs and GC responses. Pharmacological isolation of different retinal circuits found that OPs are generated by inner retinal AC electrical synapses. Importantly, this AC activity helped synchronise GC activity. CONCLUSION Our µERG protocol simultaneously records the light-dependent activities of the first-, second-, and third-order neurons within the native neuronal circuitry, providing unprecedented insights into retinal physiology and pathophysiology. This method now also enables complete in vitro retinal function testing of therapeutic interventions, providing critical guidance for later in vivo investigations.
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Affiliation(s)
- Wadood Haq
- Centre for Ophthalmology, Institute for Ophthalmic Research, Elfriede-Aulhorn-Straße 7, 72076 Tuebingen, Germany
| | - Eberhart Zrenner
- Centre for Ophthalmology, Institute for Ophthalmic Research, Elfriede-Aulhorn-Straße 7, 72076 Tuebingen, Germany
| | - Marius Ueffing
- Centre for Ophthalmology, Institute for Ophthalmic Research, Elfriede-Aulhorn-Straße 7, 72076 Tuebingen, Germany
| | - François Paquet-Durand
- Centre for Ophthalmology, Institute for Ophthalmic Research, Elfriede-Aulhorn-Straße 7, 72076 Tuebingen, Germany
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22
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Zhdanov A, Constable P, Manjur SM, Dolganov A, Posada-Quintero HF, Lizunov A. OculusGraphy: Signal Analysis of the Electroretinogram in a Rabbit Model of Endophthalmitis Using Discrete and Continuous Wavelet Transforms. Bioengineering (Basel) 2023; 10:708. [PMID: 37370639 DOI: 10.3390/bioengineering10060708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 06/04/2023] [Accepted: 06/09/2023] [Indexed: 06/29/2023] Open
Abstract
BACKGROUND The electroretinogram is a clinical test used to assess the function of the photoreceptors and retinal circuits of various cells in the eye, with the recorded waveform being the result of the summated response of neural generators across the retina. METHODS The present investigation involved an analysis of the electroretinogram waveform in both the time and time-frequency domains through the utilization of the discrete wavelet transform and continuous wavelet transform techniques. The primary aim of this study was to monitor and evaluate the effects of treatment in a New Zealand rabbit model of endophthalmitis via electroretinogram waveform analysis and to compare these with normal human electroretinograms. RESULTS The wavelet scalograms were analyzed using various mother wavelets, including the Daubechies, Ricker, Wavelet Biorthogonal 3.1 (bior3.1), Morlet, Haar, and Gaussian wavelets. Distinctive variances were identified in the wavelet scalograms between rabbit and human electroretinograms. The wavelet scalograms in the rabbit model of endophthalmitis showed recovery with treatment in parallel with the time-domain features. CONCLUSIONS The study compared adult, child, and rabbit electroretinogram responses using DWT and CWT, finding that adult signals had higher power than child signals, and that rabbit signals showed differences in the a-wave and b-wave depending on the type of response tested, while the Haar wavelet was found to be superior in visualizing frequency components in electrophysiological signals for following the treatment of endophthalmitis and may give additional outcome measures for the management of retinal disease.
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Affiliation(s)
- Aleksei Zhdanov
- Machine Learning and Data Analytics Lab, University of Erlangen-Nuremberg, 91052 Erlangen, Germany
- Engineering School of Information Technologies, Telecommunications and Control Systems, Ural Federal University Named after the First President of Russia B. N. Yeltsin, 620002 Yekaterinburg, Russia
| | - Paul Constable
- College of Nursing and Health Sciences, Caring Futures Institute, Flinders University, Adelaide, SA 5042, Australia
| | | | - Anton Dolganov
- Engineering School of Information Technologies, Telecommunications and Control Systems, Ural Federal University Named after the First President of Russia B. N. Yeltsin, 620002 Yekaterinburg, Russia
| | | | - Aleksander Lizunov
- Department of Functional Diagnostics, IRTC Eye Microsurgery Ekaterinburg Center, 620149 Yekaterinburg, Russia
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Zhao D, Pinares-Garcia P, McKenzie CE, Bleakley LE, Forster IC, Wong VHY, Nguyen CTO, Scheffer IE, Reid CA, Bui BV. Retinal Dysfunction in a Mouse Model of HCN1 Genetic Epilepsy. J Neurosci 2023; 43:2199-2209. [PMID: 36813574 PMCID: PMC10039744 DOI: 10.1523/jneurosci.1615-22.2022] [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: 08/25/2022] [Revised: 12/06/2022] [Accepted: 12/09/2022] [Indexed: 02/24/2023] Open
Abstract
Pathogenic variants in HCN1 are associated with a range of epilepsy syndromes including a developmental and epileptic encephalopathy. The recurrent de novo HCN1 pathogenic variant (M305L) results in a cation leak, allowing the flux of excitatory ions at potentials where the wild-type channels are closed. The Hcn1M294L mouse recapitulates patient seizure and behavioral phenotypes. As HCN1 channels are highly expressed in rod and cone photoreceptor inner segments, where they shape the light response, mutated channels are likely to impact visual function. Electroretinogram (ERG) recordings from male and female mice Hcn1M294L mice revealed a significant decrease in the photoreceptor sensitivity to light, as well as attenuated bipolar cell (P2) and retinal ganglion cell responses. Hcn1M294L mice also showed attenuated ERG responses to flickering lights. ERG abnormalities are consistent with the response recorded from a single female human subject. There was no impact of the variant on the structure or expression of the Hcn1 protein in the retina. In silico modeling of photoreceptors revealed that the mutated HCN1 channel dramatically reduced light-induced hyperpolarization, resulting in more Ca2+ flux during the response when compared with the wild-type situation. We propose that the light-induced change in glutamate release from photoreceptors during a stimulus will be diminished, significantly blunting the dynamic range of this response. Our data highlight the importance of HCN1 channels to retinal function and suggest that patients with HCN1 pathogenic variants are likely to have a dramatically reduced sensitivity to light and a limited ability to process temporal information.SIGNIFICANCE STATEMENT Pathogenic variants in HCN1 are emerging as an important cause of catastrophic epilepsy. HCN1 channels are ubiquitously expressed throughout the body, including the retina. Electroretinogram recordings from a mouse model of HCN1 genetic epilepsy showed a marked decrease in the photoreceptor sensitivity to light and a reduced ability to respond to high rates of light flicker. No morphologic deficits were noted. Simulation data suggest that the mutated HCN1 channel blunts light-induced hyperpolarization and consequently limits the dynamic range of this response. Our results provide insights into the role HCN1 channels play in retinal function as well as highlighting the need to consider retinal dysfunction in disease caused by HCN1 variants. The characteristic changes in the electroretinogram open the possibility of using this tool as a biomarker for this HCN1 epilepsy variant and to facilitate development of treatments.
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Affiliation(s)
- Da Zhao
- Department of Optometry and Vision Sciences, School of Health Sciences, Faculty of Medicine Dentistry and Health Sciences, University of Melbourne, Parkville 3010, Victoria, Australia
| | - Paulo Pinares-Garcia
- Early Development Division, Florey Institute of Neuroscience and Mental Health, Parkville 3010, Victoria, Australia
| | - Chaseley E McKenzie
- Early Development Division, Florey Institute of Neuroscience and Mental Health, Parkville 3010, Victoria, Australia
| | - Lauren E Bleakley
- Early Development Division, Florey Institute of Neuroscience and Mental Health, Parkville 3010, Victoria, Australia
| | - Ian C Forster
- Early Development Division, Florey Institute of Neuroscience and Mental Health, Parkville 3010, Victoria, Australia
| | - Vickie H Y Wong
- Department of Optometry and Vision Sciences, School of Health Sciences, Faculty of Medicine Dentistry and Health Sciences, University of Melbourne, Parkville 3010, Victoria, Australia
| | - Christine T O Nguyen
- Department of Optometry and Vision Sciences, School of Health Sciences, Faculty of Medicine Dentistry and Health Sciences, University of Melbourne, Parkville 3010, Victoria, Australia
| | - Ingrid E Scheffer
- Early Development Division, Florey Institute of Neuroscience and Mental Health, Parkville 3010, Victoria, Australia
- Epilepsy Research Centre, Department of Medicine, University of Melbourne/Austin Health, Heidelberg 3084, Victoria, Australia
- Murdoch Children's Research Institute, The Royal Children's Hospital, Parkville 3052, VIC Australia
- Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Parkville 3052, Victoria Australia
| | - Christopher A Reid
- Early Development Division, Florey Institute of Neuroscience and Mental Health, Parkville 3010, Victoria, Australia
- Epilepsy Research Centre, Department of Medicine, University of Melbourne/Austin Health, Heidelberg 3084, Victoria, Australia
| | - Bang V Bui
- Department of Optometry and Vision Sciences, School of Health Sciences, Faculty of Medicine Dentistry and Health Sciences, University of Melbourne, Parkville 3010, Victoria, Australia
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24
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Liu S, Yuan F, Xiang M. Comparative analysis of electroretinogram with subdermal and invasive recording methods in mice. Biochem Biophys Res Commun 2023; 655:118-126. [PMID: 36934587 DOI: 10.1016/j.bbrc.2023.03.029] [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: 02/24/2023] [Accepted: 03/10/2023] [Indexed: 03/12/2023]
Abstract
Electroretinogram (ERG) is the most common clinical and basic visual electrodiagnostic test, which has long been used to evaluate the retinal function through photic stimulation. Despite its wide application, there are still some pitfalls often neglected in ERG recording, such as the recording time point, active electrode location, and the animal strain. In this study, we systematically analyzed and compared the effects of multiple factors on ERG, which would provide an important reference for ERG detection by other investigators. ERG was recorded using the Celeris D430 rodent ERG testing system. The amplitudes and latencies of a wave, b wave and oscillatory potentials (OPs) recorded from different electrode locations (subdermal and invasive), different times of day (day time 8:00 to 13:00 and night time 18:00 to 23:00), bilateral eyes (left and right), and different mouse strains (C57 and CD1) were analyzed and compared. Our results revealed that ERG was affected by active electrode locations and difference between day and night, while OPs seemed not to be influenced. There was no significant difference in the amplitudes or latencies of ERG and OPs between left and right eyes, irrespective of measurements at day or night, or which method was used. Compared to C57 mice, both ERG and OP responses were significantly decreased in Brn3bAP/AP mice, a model for retinal ganglion cell (RGC) loss. In addition, there were some non-negligible differences in visual responses between C57 and CD1 mouse strains. Our results suggest that the invasive procedure is a reliable method for evaluating the visual function including VEP, ERG and OP responses in mice. Moreover, these comparative analyses provide valuable references for future studies of mammalian visual electrophysiology.
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Affiliation(s)
- Shuting Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - Fa Yuan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - Mengqing Xiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China.
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25
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Zahra S, Murphy MJ, Crewther SG, Riddell N. Flash Electroretinography as a Measure of Retinal Function in Myopia and Hyperopia: A Systematic Review. Vision (Basel) 2023; 7:vision7010015. [PMID: 36977295 PMCID: PMC10052972 DOI: 10.3390/vision7010015] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 02/13/2023] [Accepted: 02/22/2023] [Indexed: 03/08/2023] Open
Abstract
Refractive errors (myopia and hyperopia) are the most common visual disorders and are severe risk factors for secondary ocular pathologies. The development of refractive errors has been shown to be associated with changes in ocular axial length, suggested to be induced by outer retinal elements. Thus, the present study systematically reviewed the literature examining retinal function as assessed using global flash electroretinograms (gfERGs) in human clinical refractive error populations. Electronic database searching via Medline, PubMed, Web of Science, Embase, Psych INFO, and CINAHL retrieved 981 unique records (last searched on the 29 May 2022). Single case studies, samples with ocular comorbidities, drug trials, and reviews were excluded. Demographic characteristics, refractive state, gfERG protocol details, and waveform characteristics were extracted for the eight studies that met the inclusion criteria for the review and were judged to have acceptable risk of bias using the OHAT tool (total N = 552 participants; age 7 to 50). Study synthesis suggests that myopia in humans involves attenuation of gfERG photoreceptor (a-wave) and bipolar cell (b-wave) function, consistent with the animal literature. Meaningful interpretation of the overall findings for hyperopia was limited by inconsistent reporting, highlighting the need for future studies to report key aspects of gfERG research design and outcomes more consistently for myopic and hyperopic refractive errors.
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Affiliation(s)
- Sania Zahra
- Department of Psychology, Counselling and Therapy, La Trobe University, Melbourne 3083, Australia
| | - Melanie J. Murphy
- Department of Psychology, Counselling and Therapy, La Trobe University, Melbourne 3083, Australia
| | - Sheila G. Crewther
- Department of Psychology, Counselling and Therapy, La Trobe University, Melbourne 3083, Australia
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne 3122, Australia
| | - Nina Riddell
- Department of Psychology, Counselling and Therapy, La Trobe University, Melbourne 3083, Australia
- Correspondence:
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26
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Spitsbergen JB, Webster SE, Linn CL. Functional Changes in the Adult Mouse Retina using an Alpha7 Nicotinic Acetylcholine Receptor Agonist after Blast Exposure. Neuroscience 2023; 512:1-15. [PMID: 36572172 DOI: 10.1016/j.neuroscience.2022.12.017] [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: 06/17/2022] [Revised: 12/13/2022] [Accepted: 12/18/2022] [Indexed: 12/25/2022]
Abstract
Currently, there is a lack of treatments for retinal neurotrauma. To address this issue, this study uses an alpha7 nAChR agonist, PNU-282987, to determine it effects on functional activity in the retina shortly after a traumatic blast exposure. The objectives of this research include: (1) examination of the cellular and functional damage associated with ocular blast exposure, and (2) evaluation of structural and functional changes that occur post PNU-282987 treatment. Significant ocular blast damage was induced in adult mice after exposure to a single blast of 35 psi to the left eye. Blast-exposed transgenic mice expressing tdTomato Müller glia were treated daily with eyedrops containing PNU-282987 for 4 weeks following the blast exposure. Antibody staining studies in these transgenic mice was conducted to examine lineage tracing and electroretinograms (ERGs) were obtained to examine functional changes. Blast exposure caused a significant loss of cells in all retinal layers after 4 weeks. Immunohistochemical analysis demonstrated tdTomato-positive labeled photoreceptors and retinal ganglion cells in blast-exposed mice treated with PNU-282987. ERG recordings were taken from control animals, from blast-damaged animals and from animals exposed to blast followed by 4 weeks of PNU-282987 treatment. Scotopic ERG recordings from blast-exposed mice had significantly decreased amplitudes of a-wave, b-wave, oscillatory potentials and flicker frequencies, which were prevented after PNU-282987 treatment. In photopic experiments, the PhNR response was reduced significantly after blast exposure but the decrease was prevented after treatment with PNU-282987. These are the first experiments that demonstrate preservation of retinal function after blast exposure using an alpha7 nAChR agonist.
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Affiliation(s)
- Jake B Spitsbergen
- Western Michigan University, Department of Biological Sciences, Kalamazoo, MI 49008, USA
| | - Sarah E Webster
- Western Michigan University, Department of Biological Sciences, Kalamazoo, MI 49008, USA
| | - Cindy L Linn
- Western Michigan University, Department of Biological Sciences, Kalamazoo, MI 49008, USA.
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27
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Alves JN, Westner BU, Højlund A, Weil RS, Dalal SS. Structural and functional changes in the retina in Parkinson's disease. J Neurol Neurosurg Psychiatry 2023; 94:448-456. [PMID: 36806480 PMCID: PMC7614544 DOI: 10.1136/jnnp-2022-329342] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 01/05/2023] [Indexed: 02/19/2023]
Abstract
Parkinson's disease is caused by degeneration of dopaminergic neurons, originating in the substantia nigra pars compacta and characterised by bradykinesia, rest tremor and rigidity. In addition, visual disorders and retinal abnormalities are often present and can be identified by decreased visual acuity, abnormal spatial contrast sensitivity or even difficulty in complex visual task completion. Because of their early onset in patients with de novo Parkinson's disease, the anatomical retinal changes and electrophysiological modification could be valuable markers even at early stages of the disease. However, due to the concomitant occurrence of normal ageing, the relevance and specificity of these predictive values can be difficult to interpret. This review examines retinal dysfunction arising in Parkinson's disease. We highlight the electrophysiological delays and decreased amplitude in the electroretinography recorded in patients and animal models. We relate this to coexisting anatomical changes such as retinal nerve fibre layer and macular thinning, measured using optical coherence tomography, and show that functional measures are more consistent overall than optical coherence-measured structural changes. We review the underlying chemical changes seen with loss of retinal dopaminergic neurons and the effect of levodopa treatment on the retina in Parkinson's disease. Finally, we consider whether retinal abnormalities in Parkinson's disease could have a role as potential markers of poorer outcomes and help stratify patients at early stages of the disease. We emphasise that retinal measures can be valuable, accessible and cost-effective methods in the early evaluation of Parkinson's disease pathogenesis with potential for patient stratification.
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Affiliation(s)
- Jordan N Alves
- Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| | - Britta U Westner
- Radboud University, Donders Institute for Brain, Cognition and Behaviours, Nijmegen, The Netherlands
| | - Andreas Højlund
- Department of Linguistics, Cognitive Science & Semiotics, Aarhus University, Aarhus, Denmark
| | - Rimona Sharon Weil
- Dementia Research Centre, University College London, London, UK.,Movement Disorders Consortium, University College London, London, UK.,Wellcome Centre for Human Neuroimaging, University College London, London, UK
| | - Sarang S Dalal
- Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
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28
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Chiang TK, Yu M. Electrophysiological Evaluation of Macular Dystrophies. J Clin Med 2023; 12:jcm12041430. [PMID: 36835965 PMCID: PMC9962076 DOI: 10.3390/jcm12041430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/06/2023] [Accepted: 02/09/2023] [Indexed: 02/15/2023] Open
Abstract
Macular dystrophies are a heterogeneous group of genetic disorders that often severely threatens the bilateral central vision of the affected patient. While advances in molecular genetics have been instrumental in the understanding and diagnosis of these disorders, there remains significant phenotypical variation among patients within any particular subset of macular dystrophies. Electrophysiological testing remains a vital tool not only to characterize vision loss for differential diagnosis but also to understand the pathophysiology of these disorders and to monitor the treatment effect, potentially leading to therapeutic advances. This review summarizes the application of electrophysiological testing in macular dystrophies, including Stargardt disease, bestrophinopathies, X-linked retinoschisis, Sorsby fundus dystrophy, Doyne honeycomb retina dystrophy, autosomal dominant drusen, occult macular dystrophy, North Carolina macular dystrophy, pattern dystrophy, and central areolar choroidal dystrophy.
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29
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Origin of Retinal Oscillatory Potentials in the Mouse, a Tool to Specifically Locate Retinal Damage. Int J Mol Sci 2023; 24:ijms24043126. [PMID: 36834538 PMCID: PMC9958948 DOI: 10.3390/ijms24043126] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 01/29/2023] [Accepted: 01/30/2023] [Indexed: 02/08/2023] Open
Abstract
To determine the origin of oscillatory potentials (OPs), binocular electroretinogram (ERG) recordings were performed under light and dark adaptation on adult healthy C57BL/6J mice. In the experimental group, 1 μL of PBS was injected into the left eye, while the right eye was injected with 1 μL of PBS containing different agents: APB, GABA, Bicuculline, TPMPA, Glutamate, DNQX, Glycine, Strychnine, or HEPES. The OP response depends on the type of photoreceptors involved, showing their maximum response amplitude in the ERG induced by mixed rod/cone stimulation. The oscillatory components of the OPs were affected by the injected agents, with some drugs inducing the complete abolition of oscillations (APB, GABA, Glutamate, or DNQX), whereas other drugs merely reduced the oscillatory amplitudes (Bicuculline, Glycine, Strychnine, or HEPES) or did not even affect the oscillations (TPMPA). Assuming that rod bipolar cells (RBC) express metabotropic Glutamate receptors, GABAA, GABAC, and Glycine receptors and that they release glutamate mainly on Glycinergic AII amacrine cells and GABAergic A17 amacrine cells, which are differently affected by the mentioned drugs, we propose that RBC-AII/A17 reciprocal synapses are responsible for the OP generation in the ERG recordings in the mice. We conclude that the reciprocal synapses between RBC and AII/A17 are the basis of the ERG OP oscillations of the light response, and this fact must be taken into consideration in any ERG test that shows a decrease in the OPs' amplitude.
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30
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Preventable risk factors for type 2 diabetes can be detected using noninvasive spontaneous electroretinogram signals. PLoS One 2023; 18:e0278388. [PMID: 36634073 PMCID: PMC9836271 DOI: 10.1371/journal.pone.0278388] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 11/15/2022] [Indexed: 01/13/2023] Open
Abstract
Given the ever-increasing prevalence of type 2 diabetes and obesity, the pressure on global healthcare is expected to be colossal, especially in terms of blindness. Electroretinogram (ERG) has long been perceived as a first-use technique for diagnosing eye diseases, and some studies suggested its use for preventable risk factors of type 2 diabetes and thereby diabetic retinopathy (DR). Here, we show that in a non-evoked mode, ERG signals contain spontaneous oscillations that predict disease cases in rodent models of obesity and in people with overweight, obesity, and metabolic syndrome but not yet diabetes, using one single random forest-based model. Classification performance was both internally and externally validated, and correlation analysis showed that the spontaneous oscillations of the non-evoked ERG are altered before oscillatory potentials, which are the current gold-standard for early DR. Principal component and discriminant analysis suggested that the slow frequency (0.4-0.7 Hz) components are the main discriminators for our predictive model. In addition, we established that the optimal conditions to record these informative signals, are 5-minute duration recordings under daylight conditions, using any ERG sensors, including ones working with portative, non-mydriatic devices. Our study provides an early warning system with promising applications for prevention, monitoring and even the development of new therapies against type 2 diabetes.
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Lee PY, Zhao D, Wong VHY, Hoang A, Tran KKN, van Koeverden AK, Afiat BC, Nguyen CTO, Bui BV. Measuring the Full-Field Electroretinogram in Rodents. Methods Mol Biol 2023; 2708:131-140. [PMID: 37558967 DOI: 10.1007/978-1-0716-3409-7_14] [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] [Indexed: 08/11/2023]
Abstract
Electroretinography allows for noninvasive functional assessment of the retina and is a mainstay for preclinical studies of retinal function in health and disease. The full-field electroretinogram is useful for a variety of applications as it returns a functional readout from each of the major cell classes within the retina: photoreceptors, bipolar cells, amacrine cells, and retinal ganglion cells. Rodent models are commonly employed in ocular degeneration studies due to the fast throughput of these mammalian species and the conservation of the electroretinogram from the preclinic to the clinic. Here we describe approaches for in vivo electroretinography in rodent models.
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Affiliation(s)
- Pei Ying Lee
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Da Zhao
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Vickie H Y Wong
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Anh Hoang
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Katie K N Tran
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Anna K van Koeverden
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Brianna C Afiat
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Christine T O Nguyen
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Bang V Bui
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia.
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Proinflammatory Cytokines Trigger the Onset of Retinal Abnormalities and Metabolic Dysregulation in a Hyperglycemic Mouse Model. J Ophthalmol 2023; 2023:7893104. [PMID: 36895267 PMCID: PMC9991478 DOI: 10.1155/2023/7893104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 01/22/2023] [Accepted: 02/03/2023] [Indexed: 03/06/2023] Open
Abstract
Purpose Recent evidence has shown that retinal inflammation is a key player in diabetic retinopathy (DR) pathogenesis. To further understand and validate the metabolic biomarkers of DR, we investigated the effect of intravitreal proinflammatory cytokines on the retinal structure, function, and metabolism in an in vivo hyperglycemic mouse model. Methods C57Bl/6 mice were rendered hyperglycemic within one week of administration of a single high-dose intraperitoneal injection of streptozotocin, while control mice received vehicle injection. After confirming hyperglycemia, the mice received an intravitreal injection of either proinflammatory cytokines (TNF-α and IL-1β) or vehicle. Similarly, control mice received an intravitreal injection of either proinflammatory cytokines or vehicle. The retinal structure was evaluated using fundus imaging and optical coherence tomography, and retinal function was assessed using a focal electroretinogram (ERG), two days after cytokine injection. Retinas were collected for biochemical analysis to determine key metabolite levels and enzymatic activities. Results Hyperglycemic mice intraocularly injected with cytokines developed visible retinal vascular damage and intravitreal and intraretinal hyper-reflective spots two days after the cytokines injection. These mice also developed a significant functional deficit with reduced a-wave and b-wave amplitudes of the ERG at high light intensities compared to control mice. Furthermore, metabolic disruption was evident in these mice, with significantly higher retinal glucose, lactate, ATP, and glutamine levels and a significant reduction in glutamate levels compared with control mice. Minimal or no metabolic changes were observed in hyperglycemic mice without intraocular cytokines or in control mice with intraocular cytokines at 2 days post hyperglycemia. Conclusions Proinflammatory cytokines accelerated the development of vascular damage in the eyes of hyperglycemic mice. Significant changes were observed in retinal structure, function, and metabolic homeostasis. These findings support the idea that with the onset of inflammation in DR, there is a deficit in metabolism. Therefore, early intervention to prevent inflammation-induced retinal changes in diabetic patients may improve the disease outcome.
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Huang WC, Liu PK, Wang NK. Electroretinogram (ERG) to Evaluate the Retina in Cases of Retinitis Pigmentosa (RP). Methods Mol Biol 2023; 2560:111-122. [PMID: 36481888 DOI: 10.1007/978-1-0716-2651-1_10] [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] [Indexed: 12/13/2022]
Abstract
Electroretinogram (ERG) captures the electrical responses of photoreceptors, the summation of action potentials from all neurons in the retina elicited by illumination. ERG testing is an incredibly useful tool in obtaining more specific information regarding a retinal dystrophy. Specifically, ERGs are typically used to test photoreceptors and inner retinal function in humans and animals, to diagnose retinal dystrophies, and to monitor disease progression. In this chapter, we will introduce the components of ERGs and the standard ERG protocols for clinical examination. We will also introduce the various specialized ERG tests, which can help to differentiate retinitis pigmentosa (RP) from other retinal disorders. Lastly, we will elaborate on how to use ERGs to predict visual prognosis in RP.
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Affiliation(s)
- Wan-Chun Huang
- Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, Columbia University, New York, NY, USA
| | - Pei-Kang Liu
- Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, Columbia University, New York, NY, USA
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Nan-Kai Wang
- Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, Columbia University, New York, NY, USA.
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Zhao D, Lee PY, Wong VHY, Nishimura T, Hoang A, Tran KKN, van Koeverden AK, Afiat BC, Nguyen CTO, Bui BV. Retinal Assessment Using In Vivo Electroretinography and Optical Coherence Tomography in Rodent Models of Diabetes. Methods Mol Biol 2023; 2678:37-48. [PMID: 37326704 DOI: 10.1007/978-1-0716-3255-0_4] [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] [Indexed: 06/17/2023]
Abstract
Electroretinography and optical coherence tomography imaging allow for non-invasive quantitative assessment of the retina. These approaches have become mainstays for identifying the very earliest impact of hyperglycemia on retinal function and structure in animal models of diabetic eye disease. Moreover, they are essential for assessing the safety and efficacy of novel treatment approaches for diabetic retinopathy. Here, we describe approaches for in vivo electroretinography and optical coherence tomography imaging in rodent models of diabetes.
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Affiliation(s)
- Da Zhao
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Pei Ying Lee
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Vickie H Y Wong
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Tomoharu Nishimura
- Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, Saitama, Japan
| | - Anh Hoang
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Katie K N Tran
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Anna K van Koeverden
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Brianna C Afiat
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Christine T O Nguyen
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Bang V Bui
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, VIC, Australia.
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Mesnard CS, Hays CL, Barta CL, Sladek AL, Grassmeyer JJ, Hinz KK, Quadros RM, Gurumurthy CB, Thoreson WB. Synaptotagmins 1 and 7 in vesicle release from rods of mouse retina. Exp Eye Res 2022; 225:109279. [PMID: 36280223 PMCID: PMC9830644 DOI: 10.1016/j.exer.2022.109279] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 09/14/2022] [Accepted: 10/10/2022] [Indexed: 01/13/2023]
Abstract
Synaptotagmins are the primary Ca2+ sensors for synaptic exocytosis. Previous work suggested synaptotagmin-1 (Syt1) mediates evoked vesicle release from cone photoreceptor cells in the vertebrate retina whereas release from rods may involve another sensor in addition to Syt1. We found immunohistochemical evidence for syntaptotagmin-7 (Syt7) in mouse rod terminals and so performed electroretinograms (ERG) and single-cell recordings using mice in which Syt1 and/or Syt7 were conditionally removed from rods and/or cones. Synaptic release was measured in mouse rods by recording presynaptic anion currents activated during glutamate re-uptake and from exocytotic membrane capacitance changes. Deleting Syt1 from rods reduced glutamate release evoked by short depolarizing steps but not long steps whereas deleting Syt7 from rods reduced release evoked by long but not short steps. Deleting both sensors completely abolished depolarization-evoked release from rods. Effects of various intracellular Ca2+ buffers showed that Syt1-mediated release from rods involves vesicles close to ribbon-associated Ca2+ channels whereas Syt7-mediated release evoked by longer steps involves more distant release sites. Spontaneous release from rods was unaffected by eliminating Syt7. While whole animal knockout of Syt7 slightly reduced ERG b-waves and oscillatory potentials, selective elimination of Syt7 from rods had no effect on ERGs. Furthermore, eliminating Syt1 from rods and cones abolished ERG b-waves and additional elimination of Syt7 had no further effect. These results show that while Syt7 contributes to slow non-ribbon release from rods, Syt1 is the principal sensor shaping rod and cone inputs to bipolar cells in response to light flashes.
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Affiliation(s)
- C S Mesnard
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, USA; Pharmacology and Experimental Neuroscience, USA
| | - C L Hays
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, USA
| | - C L Barta
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, USA
| | - A L Sladek
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, USA
| | - J J Grassmeyer
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, USA; Pharmacology and Experimental Neuroscience, USA
| | - K K Hinz
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, USA
| | - R M Quadros
- Pharmacology and Experimental Neuroscience, USA; Mouse Genome Engineering Core Facility, Vice Chancellor for Research Office, College of Medicine, University of Nebraska Medical Center, Omaha, NE, 68106, USA
| | - C B Gurumurthy
- Pharmacology and Experimental Neuroscience, USA; Mouse Genome Engineering Core Facility, Vice Chancellor for Research Office, College of Medicine, University of Nebraska Medical Center, Omaha, NE, 68106, USA
| | - W B Thoreson
- Truhlsen Eye Institute and Department of Ophthalmology and Visual Sciences, USA; Pharmacology and Experimental Neuroscience, USA.
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Amato R, Catalani E, Dal Monte M, Cammalleri M, Cervia D, Casini G. Morpho-functional analysis of the early changes induced in retinal ganglion cells by the onset of diabetic retinopathy: The effects of a neuroprotective strategy. Pharmacol Res 2022; 185:106516. [DOI: 10.1016/j.phrs.2022.106516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/05/2022] [Accepted: 10/14/2022] [Indexed: 10/31/2022]
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Friedel EBN, Schäfer M, Endres D, Maier S, Runge K, Bach M, Heinrich SP, Ebert D, Domschke K, Tebartz van Elst L, Nickel K. Electroretinography in adults with high-functioning autism spectrum disorder. Autism Res 2022; 15:2026-2037. [PMID: 36217563 DOI: 10.1002/aur.2823] [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] [Received: 07/25/2022] [Accepted: 09/19/2022] [Indexed: 12/15/2022]
Abstract
The electroretinogram (ERG) allows the investigation of retinal signaling pathways and has increasingly been applied in individuals with mental disorders in search for potential biomarkers of neurodevelopmental disorders. Preceding ERG examinations in individuals with autism spectrum disorders (ASD) showed inconsistent results, which might be due to the small number of participants, heterogeneity of the ASD population, differences in age ranges, and stimulation methods. The aim of this study was to investigate functional retinal responses in adults with ASD by means of the light-adapted (photopic) ERG. Light-adapted ERG measurements were obtained with the RETeval® system applying three different stimulation protocols. In the final analysis, the ERG parameters a-wave, b-wave, the photopic negative response (PhNR), the photopic hill parameters as well as additional amplitude ratios were compared between 32 adults with high-functioning ASD and 31 non-autistic controls. Both groups were matched with regard to sex and age. No significant functional retinal differences in amplitude or peak time of the a- or b-wave, PhNR, the photopic hill parameters or the ERG-amplitude ratios could be detected in individuals with ASD compared to non-autistic participants. The absence of electrophysiological functional retinal alterations in ASD, suggests that changes in visual perception, such as increased attention to detail or visual hypersensitivity in ASD, are not due to impairments at early levels of retinal signal processing.
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Affiliation(s)
- Evelyn B N Friedel
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Mirjam Schäfer
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Dominique Endres
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Simon Maier
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Kimon Runge
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Michael Bach
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sven P Heinrich
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Dieter Ebert
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Katharina Domschke
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Center for Basics in Neuromodulation, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ludger Tebartz van Elst
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Kathrin Nickel
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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The Development of Electroretinographic Oscillatory Potentials in Healthy Young Children. J Clin Med 2022; 11:jcm11195967. [PMID: 36233838 PMCID: PMC9571328 DOI: 10.3390/jcm11195967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 09/27/2022] [Accepted: 09/28/2022] [Indexed: 11/16/2022] Open
Abstract
PURPOSE This study aimed to summarize the electroretinographic oscillatory potential (OP) responses in healthy young children recorded by RETeval. METHODS By using the RETeval system, we recorded the implicit times and amplitudes of the OPs (OP1-5), in 132 healthy children aged from 0 to 11 years old. The age, gender, and data of implicit time and amplitude of each child were recorded and analyzed. Correlation analysis was performed between age and implicit time/amplitude. RESULTS No correlation was shown between the implicit times and amplitudes with gender. The implicit times and amplitudes of OP1-5 matured over 10 years of age, with exponential time constants of 1.9, 2.2, 1.8, 1.7, and 1.6 years and 2.1, 2.9, 2.8, 3.0, and 3.2 years, respectively. The majority of the trend occurred within the first 4.6 years. CONCLUSIONS In order to diagnose and evaluate vision-related disorders, the OP response is commonly used. The percentiles and age dependence of OP responses calculated and shown in this study could be regarded as reference data in age-matched pediatric patients.
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Mello LGM, Paraguay IBB, Andrade TDS, Rocha AADN, Barbosa ER, Oyamada MK, Monteiro MLR. Electroretinography reveals retinal dysfunction in Parkinson's disease despite normal high-resolution optical coherence tomography findings. Parkinsonism Relat Disord 2022; 101:90-95. [PMID: 35810523 DOI: 10.1016/j.parkreldis.2022.06.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 06/19/2022] [Accepted: 06/20/2022] [Indexed: 10/17/2022]
Abstract
INTRODUCTION Parkinson's disease (PD)-associated inner retinal abnormalities, particularly the retinal ganglion cells (RGC) layer, on optical coherence tomography (OCT) have recently gained importance as a biomarker of non-motor involvement of the disease but functional RGC evaluation using photopic negative response (PhNR) has not yet been determined. This study aims to compare structural and functional findings of the retina and optic nerve in PD with healthy controls (CT) including PhNR and OCT. METHODS Forty-one eyes of 21 PD patients and 38 eyes of 19 CT underwent ophthalmic examination including visual contrast sensitivity test (CS), OCT, light-adapted full-field electroretinography (ffERG), and PhNR. OCT was used to measure the peripapillary retinal nerve fiber layer, the segmented macular layers, and the choroid. For functional parameters, CS, ffERG (oscillatory potentials, photopic response, 30 Hz-flicker), and PhNR waves were used. Measurements were compared using generalized estimating equation and significance was set at P ≤ 0.05. RESULTS The PD group presented a significantly lower mono- and binocular CS, oscillatory potentials amplitude, b-wave amplitude on ffERG (152.3[45.4] vs 187.1[32.7]μV; P = 0.002), and PhNR amplitude (135.0[35.0] vs 156.3[34.1]μV; P = 0.025). There was no statistically significant difference in OCT measurements between groups. No correlation was found between statistically significant measurements and clinical data. CONCLUSIONS Functional abnormalities on CS, ffERG, and PhNR can be detected in PD even when structural damages are not observed on OCT. PhNR represents a new potential biomarker in PD. Our findings indicate dysfunction of bipolar, amacrine, and retinal ganglion cells in PD, probably with a cellular dysfunction overcoming morphological damage.
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Affiliation(s)
- Luiz Guilherme Marchesi Mello
- Division of Ophthalmology, Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil; Department of Specialized Medicine, Centro de Ciências da Saúde (CCS), Universidade Federal do Espírito Santo, Vitória, Brazil.
| | | | - Thais de Souza Andrade
- Division of Ophthalmology, Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil
| | | | - Egberto Reis Barbosa
- Division of Neurology, Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil
| | - Maria Kiyoko Oyamada
- Division of Ophthalmology, Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil
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Constable PA, Marmolejo-Ramos F, Gauthier M, Lee IO, Skuse DH, Thompson DA. Discrete Wavelet Transform Analysis of the Electroretinogram in Autism Spectrum Disorder and Attention Deficit Hyperactivity Disorder. Front Neurosci 2022; 16:890461. [PMID: 35733935 PMCID: PMC9207322 DOI: 10.3389/fnins.2022.890461] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 05/09/2022] [Indexed: 12/30/2022] Open
Abstract
Background To evaluate the electroretinogram waveform in autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) using a discrete wavelet transform (DWT) approach. Methods A total of 55 ASD, 15 ADHD and 156 control individuals took part in this study. Full field light-adapted electroretinograms (ERGs) were recorded using a Troland protocol, accounting for pupil size, with five flash strengths ranging from –0.12 to 1.20 log photopic cd.s.m–2. A DWT analysis was performed using the Haar wavelet on the waveforms to examine the energy within the time windows of the a- and b-waves and the oscillatory potentials (OPs) which yielded six DWT coefficients related to these parameters. The central frequency bands were from 20–160 Hz relating to the a-wave, b-wave and OPs represented by the coefficients: a20, a40, b20, b40, op80, and op160, respectively. In addition, the b-wave amplitude and percentage energy contribution of the OPs (%OPs) in the total ERG broadband energy was evaluated. Results There were significant group differences (p < 0.001) in the coefficients corresponding to energies in the b-wave (b20, b40) and OPs (op80 and op160) as well as the b-wave amplitude. Notable differences between the ADHD and control groups were found in the b20 and b40 coefficients. In contrast, the greatest differences between the ASD and control group were found in the op80 and op160 coefficients. The b-wave amplitude showed both ASD and ADHD significant group differences from the control participants, for flash strengths greater than 0.4 log photopic cd.s.m–2 (p < 0.001). Conclusion This methodological approach may provide insights about neuronal activity in studies investigating group differences where retinal signaling may be altered through neurodevelopment or neurodegenerative conditions. However, further work will be required to determine if retinal signal analysis can offer a classification model for neurodevelopmental conditions in which there is a co-occurrence such as ASD and ADHD.
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Affiliation(s)
- Paul A. Constable
- College of Nursing and Health Sciences, Caring Futures Institute, Flinders University, Adelaide, SA, Australia
- *Correspondence: Paul A. Constable,
| | - Fernando Marmolejo-Ramos
- Centre for Change and Complexity in Learning, The University of South Australia, Adelaide, SA, Australia
| | - Mercedes Gauthier
- Department of Ophthalmology & Visual Sciences, Faculty of Medicine and Health Sciences, McGill University, Montréal, QC, Canada
| | - Irene O. Lee
- Behavioural and Brain Sciences Unit, Population, Policy and Practice Programme, UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - David H. Skuse
- Behavioural and Brain Sciences Unit, Population, Policy and Practice Programme, UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Dorothy A. Thompson
- The Tony Kriss Visual Electrophysiology Unit, Clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom
- UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
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Tran KKN, Wong VHY, Lim JKH, Shahandeh A, Hoang A, Finkelstein DI, Bui BV, Nguyen CTO. Characterization of retinal function and structure in the MPTP murine model of Parkinson’s disease. Sci Rep 2022; 12:7610. [PMID: 35534594 PMCID: PMC9085791 DOI: 10.1038/s41598-022-11495-z] [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] [Received: 01/03/2022] [Accepted: 04/18/2022] [Indexed: 12/14/2022] Open
Abstract
AbstractIn addition to well characterized motor symptoms, visual disturbances are increasingly recognized as an early manifestation in Parkinson’s disease (PD). A better understanding of the mechanisms underlying these changes would facilitate the development of vision tests which can be used as preclinical biomarkers to support the development of novel therapeutics for PD. This study aims to characterize the retinal phenotype of a mouse model of dopaminergic dysfunction and to examine whether these changes are reversible with levodopa treatment. We use a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD to characterize the neurotoxic effects of MPTP on in vivo retinal function (electroretinography, ERG), retinal structure (optical coherence tomography, OCT) and retinal dopaminergic cell number (tyrosine hydroxylase immunohistochemistry, IHC) at two time points (21 and 45 days) post MPTP model induction. We also investigate the effect of levodopa (L-DOPA) as a proof-of-principle chronic intervention against MPTP-induced changes in the retina. We show that MPTP decreases dopaminergic amacrine cell number (9%, p < 0.05) and that a component of the ERG that involves these cells, in particular oscillatory potential (OP) peak timing, was significantly delayed at Day 45 (7–13%, p < 0.01). This functional deficit was paralleled by outer plexiform layer (OPL) thinning (p < 0.05). L-DOPA treatment ameliorated oscillatory potential deficits (7–13%, p < 0.001) in MPTP animals. Our data suggest that the MPTP toxin slows the timing of inner retinal feedback circuits related to retinal dopaminergic pathways which mirrors findings from humans with PD. It also indicates that the MPTP model causes structural thinning of the outer retinal layer on OCT imaging that is not ameliorated with L-DOPA treatment. Together, these non-invasive measures serve as effective biomarkers for PD diagnosis as well as for quantifying the effect of therapy.
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Heriot W, Wong VH, He Z, Hoang A, Lim JK, Nishimura T, Zhao D, Metha AB, Bui BV. Effect of hydroxychloroquine or chloroquine and short wavelength light on in vivo retinal function and structure in mouse eyes. Clin Exp Optom 2022:1-9. [PMID: 35483117 DOI: 10.1080/08164622.2022.2067471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
CLINICAL RELEVANCE The use of chloroquine or hydroxychloroquine can lead to both acute and chronic changes to both retinal structure and function. BACKGROUND Chloroquine (CQ) and hydroxychloroquine (HCQ) have the potential for retina toxicity. The acute impact of short-term drug exposure (2-4 weeks) on in vivo retinal structure and function and assess whether short wavelength light exposure further exacerbates any structural and functional changes was assessed in a murine model. METHODS Adult C57BL/6 J mice received intraperitoneal injection of vehicle or hydroxychloroquine (10 mg/kg) 3 times per week for 2 or 4 weeks, or chloroquine for 4 weeks (10 mg/kg). Over this period, animals were exposed to room light (8 hours) or short-wavelength light 4 hours per day (4 hours of normal room light) for 5 days each week. Retinal changes were assessed using electroretinography (ERG), in vivo optical coherence tomography (OCT) imaging. RESULTS Short-term low-dose HCQ and CQ treatment led to RPE thickening and elongation of photoreceptors. These structural changes were associated with a no dysfunction in the case of HCQ treatments and widespread functional changes (photoreceptor sensitivity, bipolar cell amplitude and oscillatory potential amplitude) in the case of CQ treatment. Exposure to low intensity short-wavelength light does not appear to alter the effect of HCQ or CQ. CONCLUSIONS HCQ and CQ treatment has acute effects on both retinal structure and function, effects that were not exacerbated by short wavelength light exposure. Whether chronic short wavelength light exposure exacerbates these changes require further study.
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Affiliation(s)
- Wilson Heriot
- Centre for Eye Research Australia, Department of Ophthalmology, University of Melbourne, Royal Victorian Eye and Ear Hospital, Victoria, Australia
| | - Vickie Hy Wong
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Zheng He
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Anh Hoang
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Jeremiah Kh Lim
- Optometry and Vision Science, College of Nursing and Health Sciences, Flinders University, Australia
| | - Tomoharu Nishimura
- Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, Koshigaya, Japan
| | - Da Zhao
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Andrew B Metha
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Bang V Bui
- Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Victoria, Australia
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The Molecular Mechanism of Retina Light Injury Focusing on Damage from Short Wavelength Light. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:8482149. [PMID: 35498134 PMCID: PMC9042598 DOI: 10.1155/2022/8482149] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 03/31/2022] [Indexed: 12/30/2022]
Abstract
Natural visible light is an electromagnetic wave composed of a spectrum of monochromatic wavelengths, each with a characteristic color. Photons are the basic units of light, and their wavelength correlates to the energy of light; short-wavelength photons carry high energy. The retina is a fragile neuronal tissue that senses light and generates visual signals conducted to the brain. However, excessive and intensive light exposure will cause retinal light damage. Within the visible spectrum, short-wavelength light, such as blue light, carries higher energy, and thus the retinal injury, is more significant when exposed to these wavelengths. The damage mechanism triggered by different short-wavelength light varies due to photons carrying different energy and being absorbed by different photosensitive molecules in the retinal neurons. However, photooxidation might be a common molecular step to initiate cell death. Herein, we summarize the historical understanding of light, the key molecular steps related to retinal light injury, and the death pathways of photoreceptors to further decipher the molecular mechanism of retinal light injury and explore potential neuroprotective strategies.
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Rao A, Padhy D, Pal A, Roy AK. Visual function tests for glaucoma practice - What is relevant? Indian J Ophthalmol 2022; 70:749-758. [PMID: 35225508 PMCID: PMC9114550 DOI: 10.4103/ijo.ijo_1390_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Glaucoma represents one of the most important ocular diseases causing irreversible ganglion cell death. It is one of the most common causes of visual impairment and morbidity in the elderly population. There are various tests for measuring visual function in glaucoma. While visual field remains the undisputed method for screening, diagnosis, and monitoring disease progression, other tests have been studied for their utility in glaucoma practice. This review discusses some of the commonly used tests of visual function that can be routinely used in clinics for glaucoma management. Among the various modalities of testing visual function in glaucoma, this review highlights the tests that are most clinically relevant.
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Affiliation(s)
- Aparna Rao
- Department of Glaucoma Services, L. V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Debananda Padhy
- Department of Glaucoma Services, L. V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Anindita Pal
- Department of Glaucoma Services, L. V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Avik Kumar Roy
- Department of Glaucoma Services, L. V. Prasad Eye Institute, Bhubaneswar, Odisha, India
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45
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Retinal Degeneration in a Murine Model of Retinal Ischemia by Unilateral Common Carotid Artery Occlusion. BIOMED RESEARCH INTERNATIONAL 2022; 2021:7727648. [PMID: 35005021 PMCID: PMC8741345 DOI: 10.1155/2021/7727648] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 01/21/2023]
Abstract
Retinal degeneration is a progressive retinal damage in ocular vascular diseases. There are several reasons for this, such as occlusion of arteries or veins, diabetic retinopathy, or hereditary retinal diseases. To study pathological mechanisms of retinal degeneration, it is required to develop experimentally reproducible and clinically relevant models. In our previous studies, we developed a murine model of retinal hypoperfusion by unilateral common carotid artery occlusion (UCCAO) which mimics the pathophysiology of ocular ischemic syndrome (OIS) in humans, and described broad pathological mechanisms in the retina after UCCAO. However, there still remain missing pieces of the ocular pathologic process by UCCAO. In this study, we examined those unfound mechanisms. UCCAO was performed on adult mice. Ocular dysfunctions, histological deficits, and inflammation were examined after UCCAO, compared with sham-operated mice. Evaluation values were analyzed by electrophysiological, histological, and molecular biological methods. Eyelid drooping was permanently seen after UCCAO. Induction time point of acute reversible cataract under anesthesia was shortened. Retinal/visual dysfunctions were detected 2-4 weeks after UCCAO. Specifically, scotopic b-wave was more affected than a-wave, with the dysfunction of photopic b-wave. Impaired oscillatory potentials and visual evoked potential were constantly observed. Pathological Müller gliosis/inflammation was featured with NeuN-positive cell loss in the ganglion cell layer. Axial length, intraocular pressure, pupillary light reflex, and retinal pigment epithelium/choroidal thickness were not changed by UCCAO. A murine model of retinal ischemia by UCCAO can be useful for studying a series of degenerative process in the ischemic retina.
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Baba K, Tosini G. Assessing the Role of Melatonin in the Modulation of Visual Functions in the Mouse. Methods Mol Biol 2022; 2550:377-389. [PMID: 36180707 DOI: 10.1007/978-1-0716-2593-4_38] [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] [Indexed: 06/16/2023]
Abstract
The electroretinogram (ERG) is a noninvasive method to evaluate retinal function. It can be applied to patients to be diagnosed a variety of retinal pathologies such as photoreceptor dystrophy, diabetic retinopathy, macular degeneration, and glaucoma. ERG has also been a reliable tool to assess retinal functions in animal studies that range from fish to humans. Melatonin is a neurohormone that regulates several retinal functions within the retina, and previous studies have shown that melatonin plays an important role in the modulation of the ERG in humans and other vertebrates. This chapter describes experimental methods to evaluate retinal function using ERG in the mouse and how to assess the contribution of melatonin. An introduction is provided for materials, environmental settings, recording procedures, and analysis necessary for ERG measurements.
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Affiliation(s)
- Kenkichi Baba
- Department of Pharmacology & Toxicology, Morehouse School of Medicine, Atlanta, GA, USA.
| | - Gianluca Tosini
- Department of Pharmacology & Toxicology, Morehouse School of Medicine, Atlanta, GA, USA
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47
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Bernardin F, Schwitzer T, Schwan R, Angioi-Duprez K, Ligier F, Bourion-Bedes S, Jansen C, Giersch A, Laprevote V. Altered central vision and amacrine cells dysfunction as marker of hypodopaminergic activity in treated patients with schizophrenia. Schizophr Res 2022; 239:134-141. [PMID: 34891077 DOI: 10.1016/j.schres.2021.11.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 10/07/2021] [Accepted: 11/28/2021] [Indexed: 12/14/2022]
Abstract
BACKGROUND Retinal dysfunction is widely documented in schizophrenia using flash (fERG) and pattern electroretinograms (PERG), but the role of dopamine transmission has seldom been explored. METHODS We explored the role of dopamine transmission by evaluating the spatial location of retinal anomalies using multifocal ERG (mfERG) in photopic condition and the oscillatory potentials (OPs) extracted from fERG measured in scotopic condition in 29 patients with schizophrenia and 29 healthy controls. RESULTS With the mfERG, our main results revealed reduced amplitudes in the center of the retina: P1 (p < .005) and N2 amplitudes (p < .01) in the <2° region, N1 (p < .0005) and P1 amplitudes (p < .001) in the 2-5° region and P1 amplitude (p < .05) in the 5-10° region. For OPs, our results showed a decrease in the O1 (p < .005), O2 (p < .005), O3 (p < .05) and overall O1, O2, O3 index amplitudes (p < .005) in patients with schizophrenia. CONCLUSIONS Both the central location of retinal dysfunctions of the mfERG and OPs results could reflect a hypodopaminergic effect in patients with schizophrenia. In future studies, OPs should be considered as a measure to evaluate the hypodopaminergy in patients.
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Affiliation(s)
- Florent Bernardin
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France; INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg, Pôle de Psychiatrie, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, France.
| | - Thomas Schwitzer
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France; INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg, Pôle de Psychiatrie, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, France; Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Raymund Schwan
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France; INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg, Pôle de Psychiatrie, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, France; Université de Lorraine, Vandœuvre-lès-Nancy, France
| | | | - Fabienne Ligier
- Pôle Universitaire de Psychiatrie de l'Enfant et de l'Adolescent, Centre Psychothérapique de Nancy, Laxou, France; Université de Lorraine, EA 4360 APEMAC, équipe MICS, France
| | - Stéphanie Bourion-Bedes
- Université de Lorraine, EA 4360 APEMAC, équipe MICS, France; Service Médico Psychologique Régional, Metz, France
| | - Claire Jansen
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France
| | - Anne Giersch
- INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg, Pôle de Psychiatrie, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, France
| | - Vincent Laprevote
- Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes et d'Addictologie du Grand Nancy, Centre Psychothérapique de Nancy, Laxou, France; INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg, Pôle de Psychiatrie, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, France; Université de Lorraine, Vandœuvre-lès-Nancy, France
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48
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Righetti G, Kempf M, Braun C, Jung R, Kohl S, Wissinger B, Zrenner E, Stingl K, Stingl K. Oscillatory Potentials in Achromatopsia as a Tool for Understanding Cone Retinal Functions. Int J Mol Sci 2021; 22:12717. [PMID: 34884517 PMCID: PMC8657736 DOI: 10.3390/ijms222312717] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/19/2021] [Accepted: 11/22/2021] [Indexed: 11/25/2022] Open
Abstract
Achromatopsia (ACHM) is an inherited autosomal recessive disease lacking cone photoreceptors functions. In this study, we characterize the time-frequency representation of the full-field electroretinogram (ffERG) component oscillatory potentials (OPs), to investigate the connections between photoreceptors and the inner retinal network using ACHM as a model. Time-frequency characterization of OPs was extracted from 52 controls and 41 achromat individuals. The stimulation via ffERG was delivered under dark-adaptation (DA, 3.0 and 10.0 cd·s·m-2) to assess mixed rod-cone responses. The ffERG signal was subsequently analyzed using a continuous complex Morlet transform. Time-frequency maps of both DA conditions show the characterization of OPs, disclosing in both groups two distinct time-frequency windows (~70-100 Hz and >100 Hz) within 50 ms. Our main result indicates a significant cluster (p < 0.05) in both conditions of reduced relative power (dB) in ACHM people compared to controls, mainly at the time-frequency window >100 Hz. These results suggest that the strongly reduced but not absent activity of OPs above 100 Hz is mostly driven by cones and only in small part by rods. Thus, the lack of cone modulation of OPs gives important insights into interactions between photoreceptors and the inner retinal network and can be used as a biomarker for monitoring cone connection to the inner retina.
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Affiliation(s)
- Giulia Righetti
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, 72076 Tübingen, Germany; (M.K.); (R.J.); (K.S.); (K.S.)
| | - Melanie Kempf
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, 72076 Tübingen, Germany; (M.K.); (R.J.); (K.S.); (K.S.)
- Center for Rare Eye Diseases, University of Tübingen, 72076 Tübingen, Germany;
| | - Christoph Braun
- MEG-Center, University of Tübingen, 72076 Tübingen, Germany;
- CIMeC, Center for Mind/Brain Science, University of Trento, 38123 Trento, Italy
| | - Ronja Jung
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, 72076 Tübingen, Germany; (M.K.); (R.J.); (K.S.); (K.S.)
| | - Susanne Kohl
- Molecular Genetics Laboratory, Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; (S.K.); (B.W.)
| | - Bernd Wissinger
- Molecular Genetics Laboratory, Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; (S.K.); (B.W.)
| | - Eberhart Zrenner
- Center for Rare Eye Diseases, University of Tübingen, 72076 Tübingen, Germany;
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of Tübingen, 72076 Tübingen, Germany
| | - Katarina Stingl
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, 72076 Tübingen, Germany; (M.K.); (R.J.); (K.S.); (K.S.)
- Center for Rare Eye Diseases, University of Tübingen, 72076 Tübingen, Germany;
| | - Krunoslav Stingl
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, 72076 Tübingen, Germany; (M.K.); (R.J.); (K.S.); (K.S.)
- Center for Rare Eye Diseases, University of Tübingen, 72076 Tübingen, Germany;
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He M, Long P, Chen T, Li K, Wei D, Zhang Y, Wang W, Hu Y, Ding Y, Wen A. ALDH2/SIRT1 Contributes to Type 1 and Type 2 Diabetes-Induced Retinopathy through Depressing Oxidative Stress. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:1641717. [PMID: 34725563 PMCID: PMC8557042 DOI: 10.1155/2021/1641717] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/07/2021] [Accepted: 09/24/2021] [Indexed: 12/11/2022]
Abstract
Clinical observations found vision-threatening diabetic retinopathy (DR) occurs in both type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) patients, but T1DM may perform more progressive retinal abnormalities at the same diabetic duration with or without clinical retinopathy. In the present study, T1DM and T2DM patients without manifestations of DR were included in our preliminary clinical retrospective observation study to investigate the differentiated retinal function at the preclinical stage. Then, T1DM and T2DM rat models with 12-week diabetic duration were constructed to explore the potential mechanism of the discrepancy in retinal disorders. Our data demonstrated T1DM patients presented a poor retinal function, a higher allele frequency for ALDH2GA/AA, and a depressed aldehyde dehydrogenase 2 (ALDH2) activity and silent information regulator 1 (SIRT1) level, compared to T2DM individuals. In line with this, higher amplitudes of neurovascular function-related waves of electroretinograms were found in T2DM rats. Furthermore, the retinal outer nuclear layers were reduced in T1DM rats. The levels of retinal oxidative stress biomarkers including total reactive oxygen species, NADPH oxidase 4 and mitochondrial DNA damage, and inflammatory indicators covering inducible/endothelial nitric acid synthase ratio, interleukin-1, and interleukin-6 were obviously elevated. Notably, the level of retinal ALDH2 and SIRT1 in T1DM rats was significantly diminished, while the expression of neovascularization factors was dramatically enhanced compared to T2DM. Together, our data indicated that the ALDH2/SIRT1 deficiency resulted in prominent oxidative stress and was in association with DR progression. Moreover, a differentiating ALDH2/SIRT1 expression may be responsible for the dissimilar severity of DR pathological processes in chronic inflammatory-related T1DM and T2DM.
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MESH Headings
- Adult
- Aldehyde Dehydrogenase, Mitochondrial/genetics
- Aldehyde Dehydrogenase, Mitochondrial/metabolism
- Animals
- Diabetes Mellitus, Experimental/complications
- Diabetes Mellitus, Experimental/enzymology
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Type 1/complications
- Diabetes Mellitus, Type 1/enzymology
- Diabetes Mellitus, Type 1/genetics
- Diabetes Mellitus, Type 2/complications
- Diabetes Mellitus, Type 2/enzymology
- Diabetes Mellitus, Type 2/genetics
- Diabetic Retinopathy/enzymology
- Diabetic Retinopathy/etiology
- Diabetic Retinopathy/genetics
- Disease Models, Animal
- Disease Progression
- Female
- Humans
- Male
- Middle Aged
- Oxidative Stress
- Rats, Sprague-Dawley
- Reactive Oxygen Species/metabolism
- Retina/enzymology
- Retina/pathology
- Retrospective Studies
- Sirtuin 1/metabolism
- Rats
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Affiliation(s)
- Mengshan He
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shaanxi, China
| | - Pan Long
- Department of Ophthalmology, The General Hospital of Western Theater Command, Chengdu, 610083 Sichuan, China
| | - Tao Chen
- Center of Clinical Aerospace Medicine, Fourth Military Medical University, Xi'an, 710032 Shaanxi, China
| | - Kaifeng Li
- Experiment Teaching Center, Fourth Military Medical University, Xi'an, 710032 Shaanxi, China
| | - Dongyu Wei
- Center of Clinical Aerospace Medicine, Fourth Military Medical University, Xi'an, 710032 Shaanxi, China
| | - Yufei Zhang
- The Air Force Hospital from Northern Theater PLA, Shenyang, 110092 Liaoning, China
| | - Wenjun Wang
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shaanxi, China
| | - Yonghe Hu
- Clinical Medical College & Affiliated Hospital of Chengdu University, Chengdu, 610081 Sichuan, China
| | - Yi Ding
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shaanxi, China
| | - Aidong Wen
- Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032 Shaanxi, China
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50
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Gao M, Telles Salgueiro Barboni M, Fix Ventura D, Nagy BV. Effects of fixed cutoff filtering on dark- and light-adapted ERG components and the application of variable cutoff filter. Doc Ophthalmol 2021; 144:191-202. [PMID: 34559355 PMCID: PMC9192464 DOI: 10.1007/s10633-021-09853-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 09/10/2021] [Indexed: 11/29/2022]
Abstract
Purpose Human oscillatory potentials (OPs) are derived from dark-adapted (DA) electroretinograms (ERGs) with fixed frequency cutoff filters while light-adapted (LA) OPs are generally not isolated from ERGs. Our purpose was to analyze the effect of cutoff frequencies on DA and LA ERG components using a series of fixed and variable filters. Methods DA and LA ERGs were recorded from 10 healthy eyes of 10 subjects (mean age = 20.5 ± 6.7 years) following ISCEV standards. Each signal was filtered in the Fourier domain to acquire slow (a- and b-waves; below cutoff frequency) and fast (OPs; above cutoff frequency) components. Fixed cutoff frequencies ranged from 60 to 105 Hz and a variable cutoff frequency was calculated. Results were analyzed with statistical tests and specific models. Results DA ERG components were slightly influenced by the filter cutoff frequency. In contrast, fixed and variable filters significantly changed LA components: the lower the cutoff frequency the smaller the b-wave and OP3 and the higher the OP2/OP4 amplitudes. Analyzing the filter frequency limits a transition range between 68.9 Hz and 83.9 Hz was observed where amplitudes vary. Conclusions The present report shows that DA OPs may be isolated from ERGs using filtering procedures with high-pass cutoff frequency at about 75 Hz as recommended by ISCEV. On the other hand, the spectral distribution of low-frequency and high-frequency LA ERG components may overlap. Accordingly, filtering the signal using different cutoff frequencies is not necessarily separating b-wave and OPs.
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Affiliation(s)
- Min Gao
- Department of Mechatronics, Optics and Mechanical Engineering Informatics, Budapest University of Technology and Economics, Budapest, Hungary
| | - Mirella Telles Salgueiro Barboni
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary.,Department of Experimental Psychology, University of Sao Paulo, Sao Paulo, Brazil
| | - Dora Fix Ventura
- Department of Experimental Psychology, University of Sao Paulo, Sao Paulo, Brazil
| | - Balázs Vince Nagy
- Department of Mechatronics, Optics and Mechanical Engineering Informatics, Budapest University of Technology and Economics, Budapest, Hungary.
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