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Wu S, Zheng F, Sui A, Wu D, Chen Z. Sodium-iodate injection can replicate retinal and choroid degeneration in pigmented mice: Using multimodal imaging and label-free quantitative proteomics analysis. Exp Eye Res 2024; 247:110050. [PMID: 39151777 DOI: 10.1016/j.exer.2024.110050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 07/12/2024] [Accepted: 08/13/2024] [Indexed: 08/19/2024]
Abstract
Age-related macular degeneration (AMD) is the leading cause of irreversible visual loss in the elderly population. Sodium iodate (NaIO3), a stable oxidizing agent, has been injected to establish a reproducible model of oxidative stress-induced RPE and photoreceptor death. The aim of our study was to evaluate the morphological and molecular changes of retina and retinal pigment epithelium (RPE)-choroid in NaIO3-treated mouse using multimodal fundus imaging and label-free quantitative proteomics analysis. Here, we found that following NaIO3 injection, retinal degeneration was evident. Fundus photographs showed numerous scattered yellow-white speckled deposits. Optical coherence tomography (OCT) images indicated disruption of the retinal layers, damage of the RPE layer and accumulation of hyper-reflective matter in multiple layers of the outer retina. Widespread foci of a high fundus autofluorescence (FAF) signal were noticed. Fundus fluorescein angiography (FFA) revealed diffuse intense transmitted fluorescence mixed with scattered spot-like blocked fluorescence. Indocyanine green angiography (ICGA) presented punctate hyperfluorescence. Due to the atrophy of the RPE and Bruch's membrane and choroidal capillary complex, the larger choroidal vessels become more prominent in ICGA and optical coherence tomography angiography (OCTA). Transmission electron microscope (TEM) illustrated abnormal material accumulation and damaged mitochondria. Bioinformatics analysis of proteomics revealed that the differentially expressed proteins participated in diverse biological processes, encompassing phototransduction, NOD-like receptor signaling pathway, phagosome, necroptosis, and cell adhesion molecules. In conclusion, by multimodal imaging, we described the phenotype of NaIO3-treated mouse model mimicking oxidative stress-induced RPE and photoreceptor death in detail. In addition, proteomics analysis identified differentially expressed proteins and significant enrichment pathways, providing insights for future research, although the exact mechanism of oxidative stress-induced RPE and photoreceptor death remains incompletely understood.
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Affiliation(s)
- Shijing Wu
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, Zhejiang, China; Zhejiang Provincial Key Laboratory of Ophthalmology, Hangzhou, 310009, Zhejiang, China
| | - Fang Zheng
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, Zhejiang, China; Zhejiang Provincial Key Laboratory of Ophthalmology, Hangzhou, 310009, Zhejiang, China
| | - Ailing Sui
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, Zhejiang, China; Zhejiang Provincial Key Laboratory of Ophthalmology, Hangzhou, 310009, Zhejiang, China
| | - Di Wu
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, Zhejiang, China; Zhejiang Provincial Key Laboratory of Ophthalmology, Hangzhou, 310009, Zhejiang, China.
| | - Zhiqing Chen
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, Zhejiang, China; Zhejiang Provincial Key Laboratory of Ophthalmology, Hangzhou, 310009, Zhejiang, China.
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2
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Noh SE, Lee SJ, Cho CS, Jo DH, Park KS, Kim JH. Mitochondrial transplantation attenuates oligomeric amyloid-beta-induced mitochondrial dysfunction and tight junction protein destruction in retinal pigment epithelium. Free Radic Biol Med 2024; 212:10-21. [PMID: 38101587 DOI: 10.1016/j.freeradbiomed.2023.12.012] [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: 09/18/2023] [Revised: 12/07/2023] [Accepted: 12/11/2023] [Indexed: 12/17/2023]
Abstract
Transplantation of mitochondria derived from mesenchymal stem cells (MSCs) has emerged as a new treatment method to improve mitochondrial dysfunction and alleviate cell impairment. Interest in using extrinsic mitochondrial transplantation as a therapeutic approach has been increasing because it has been confirmed to be effective in treating various diseases related to mitochondrial dysfunction, including ischemia, cardiovascular disease, and toxic damage. To support this application, we conducted an experiment to deliver external mitochondria to retinal pigment epithelial cells treated with oligomeric amyloid-beta (oAβ). Externally delivered amyloid-beta internalizes into cells and interacts with mitochondria, resulting in mitochondrial dysfunction and intracellular damage, including increased reactive oxygen species and destruction of tight junction proteins. Externally delivered mitochondria were confirmed to alleviate mitochondrial dysfunction and tight junction protein disruption as well as improve internalized oAβ clearance. These results were also confirmed in a mouse model in vivo. Overall, these findings indicate that the transfer of external mitochondria isolated from MSCs has potential as a new treatment method for age-related macular degeneration, which involves oAβ-induced changes to the retinal pigment epithelium.
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Affiliation(s)
- Sung-Eun Noh
- Fight Against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Global Excellence Center for Gene & Cell Therapy (GEC-GCT), Seoul National University Hospital, Seoul, Republic of Korea
| | - Seok Jae Lee
- Fight Against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Global Excellence Center for Gene & Cell Therapy (GEC-GCT), Seoul National University Hospital, Seoul, Republic of Korea
| | - Chang Sik Cho
- Fight Against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Global Excellence Center for Gene & Cell Therapy (GEC-GCT), Seoul National University Hospital, Seoul, Republic of Korea
| | - Dong Hyun Jo
- Department of Anatomy & Cell Biology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kyu Sang Park
- Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Jeong Hun Kim
- Fight Against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Global Excellence Center for Gene & Cell Therapy (GEC-GCT), Seoul National University Hospital, Seoul, Republic of Korea; Department of Biomedical Sciences & Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea; Institute of Reproductive Medicine and Population, Seoul National University College of Medicine, Seoul, Republic of Korea.
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3
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Blasiak J, Pawlowska E, Ciupińska J, Derwich M, Szczepanska J, Kaarniranta K. A New Generation of Gene Therapies as the Future of Wet AMD Treatment. Int J Mol Sci 2024; 25:2386. [PMID: 38397064 PMCID: PMC10888617 DOI: 10.3390/ijms25042386] [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: 01/19/2024] [Revised: 02/14/2024] [Accepted: 02/16/2024] [Indexed: 02/25/2024] Open
Abstract
Age-related macular degeneration (AMD) is an eye disease and the most common cause of vision loss in the Western World. In its advanced stage, AMD occurs in two clinically distinguished forms, dry and wet, but only wet AMD is treatable. However, the treatment based on repeated injections with vascular endothelial growth factor A (VEGFA) antagonists may at best stop the disease progression and prevent or delay vision loss but without an improvement of visual dysfunction. Moreover, it is a serious mental and financial burden for patients and may be linked with some complications. The recent first success of intravitreal gene therapy with ADVM-022, which transformed retinal cells to continuous production of aflibercept, a VEGF antagonist, after a single injection, has opened a revolutionary perspective in wet AMD treatment. Promising results obtained so far in other ongoing clinical trials support this perspective. In this narrative/hypothesis review, we present basic information on wet AMD pathogenesis and treatment, the concept of gene therapy in retinal diseases, update evidence on completed and ongoing clinical trials with gene therapy for wet AMD, and perspectives on the progress to the clinic of "one and done" therapy for wet AMD to replace a lifetime of injections. Gene editing targeting the VEGFA gene is also presented as another gene therapy strategy to improve wet AMD management.
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Affiliation(s)
- Janusz Blasiak
- Faculty of Medicine, Collegium Medicum, Mazovian Academy in Plock, 09-402 Plock, Poland
| | - Elzbieta Pawlowska
- Department of Pediatric Dentistry, Medical University of Lodz, 92-217 Lodz, Poland; (E.P.); (M.D.); (J.S.)
| | - Justyna Ciupińska
- Clinical Department of Infectious Diseases and Hepatology, H. Bieganski Hospital, 91-347 Lodz, Poland;
| | - Marcin Derwich
- Department of Pediatric Dentistry, Medical University of Lodz, 92-217 Lodz, Poland; (E.P.); (M.D.); (J.S.)
| | - Joanna Szczepanska
- Department of Pediatric Dentistry, Medical University of Lodz, 92-217 Lodz, Poland; (E.P.); (M.D.); (J.S.)
| | - Kai Kaarniranta
- Department of Ophthalmology, University of Eastern Finland, 70210 Kuopio, Finland;
- Department of Ophthalmology, Kuopio University Hospital, 70210 Kuopio, Finland
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Jo DH, Lee SH, Jeon M, Cho CS, Kim DE, Kim H, Kim JH. Activation of Lysosomal Function Ameliorates Amyloid-β-Induced Tight Junction Disruption in the Retinal Pigment Epithelium. Mol Cells 2023; 46:675-687. [PMID: 37968982 PMCID: PMC10654459 DOI: 10.14348/molcells.2023.0056] [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: 04/07/2023] [Revised: 10/16/2023] [Accepted: 10/17/2023] [Indexed: 11/17/2023] Open
Abstract
Accumulation of pathogenic amyloid-β disrupts the tight junction of retinal pigment epithelium (RPE), one of its senescence-like structural alterations. In the clearance of amyloid-β, the autophagy-lysosome pathway plays the crucial role. In this context, mammalian target of rapamycin (mTOR) inhibits the process of autophagy and lysosomal degradation, acting as a potential therapeutic target for age-associated disorders. However, efficacy of targeting mTOR to treat age-related macular degeneration remains largely elusive. Here, we validated the therapeutic efficacy of the mTOR inhibitors, Torin and PP242, in clearing amyloid-β by inducing the autophagy-lysosome pathway in a mouse model with pathogenic amyloid-β with tight junction disruption of RPE, which is evident in dry age-related macular degeneration. High concentration of amyloid-β oligomers induced autophagy-lysosome pathway impairment accompanied by the accumulation of p62 and decreased lysosomal activity in RPE cells. However, Torin and PP242 treatment restored the lysosomal activity via activation of LAMP2 and facilitated the clearance of amyloid-β in vitro and in vivo. Furthermore, clearance of amyloid-β by Torin and PP242 ameliorated the tight junction disruption of RPE in vivo. Overall, our findings suggest mTOR inhibition as a new therapeutic strategy for the restoration of tight junctions in age-related macular degeneration.
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Affiliation(s)
- Dong Hyun Jo
- Department of Anatomy and Cell Biology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Su Hyun Lee
- Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul 02841, Korea
| | - Minsol Jeon
- Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul 02841, Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul 02841, Korea
| | - Chang Sik Cho
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Korea
| | - Da-Eun Kim
- Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul 02841, Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul 02841, Korea
| | - Hyunkyung Kim
- Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul 02841, Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul 02841, Korea
| | - Jeong Hun Kim
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Korea
- Department of Biomedical Sciences & Ophthalmology, Seoul National University College of Medicine, Seoul 02841, Korea
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Su N, Hansen U, Plagemann T, Gäher K, Leclaire MD, König J, Höhn A, Grune T, Uhlig CE, Eter N, Heiduschka P. Sub-Retinal Injection of Human Lipofuscin in the Mouse - A Model of "Dry" Age-Related Macular Degeneration? Aging Dis 2023; 14:184-203. [PMID: 36818570 PMCID: PMC9937713 DOI: 10.14336/ad.2022.0626] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 06/26/2022] [Indexed: 11/18/2022] Open
Abstract
Lipofuscin (LF) accumulates during lifetime in the retinal pigment epithelium (RPE) and is thought to play a crucial role in intermediate and late age-related macular degeneration (AMD). In an attemt to simulate aged retina and to study response of retinal microglia and RPE cells to LF, we injected a suspension of LF into the subretinal space of adult mice. LF suspension was obtained from human donor eyes. Subretinal injection of PBS or sham injection served as a control. Eyes were inspected by autofluorescence and optical coherence tomography, by electroretinography and on histological and ultrastructural levels. Levels of cytokine mRNA were determined by quantitative PCR separately in the RPE/choroid complex and in the retina. After injection of LF, microglial cells migrated quickly into the subretinal space to close proximity to RPE cells and phagocytosed LF particles. Retinal function was affected only slightly by LF within the first two weeks. After longer time, RPE cells showed clear signs of melanin loss and degradation. Levels of mRNA of inflammatory cytokines increased sharply after injection of both PBS and LF and were higher in the RPE/choroid complex than in the retina and were slightly higher after LF injection. In conclusion, subretinal injection of LF causes an activation of microglial cells and their migration into subretinal space, enhanced expression of inflammatory cytokines and a gradual degradation of RPE cells. These features are found also in an aging retina, and subretinal injection of LF could be a model for intermediate and late AMD.
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Affiliation(s)
- Nan Su
- Research Laboratory, Department of Ophthalmology, University
Medical Center, Münster, Germany.
- Department of Ophthalmology, The First Affiliated Hospital of
Zhengzhou University, Zhengzhou, China.
| | - Uwe Hansen
- Institute of Musculoskeletal Medicine, Medical Faculty,
University of Münster, Münster, Germany.
| | - Tanja Plagemann
- Research Laboratory, Department of Ophthalmology, University
Medical Center, Münster, Germany.
| | - Karin Gäher
- Institute of Musculoskeletal Medicine, Medical Faculty,
University of Münster, Münster, Germany.
| | - M. Dominik Leclaire
- Research Laboratory, Department of Ophthalmology, University
Medical Center, Münster, Germany.
| | - Jeannette König
- German Institute of Human Nutrition,
Potsdam-Rehbrücke, Germany.
| | - Annika Höhn
- German Institute of Human Nutrition,
Potsdam-Rehbrücke, Germany.
| | - Tilman Grune
- German Institute of Human Nutrition,
Potsdam-Rehbrücke, Germany.
| | - Constantin E. Uhlig
- Cornea Bank Münster, Department of Ophthalmology,
University Medical Center, Münster, Germany.
| | - Nicole Eter
- Department of Ophthalmology, University Medical Center,
Münster, Germany.
| | - Peter Heiduschka
- Research Laboratory, Department of Ophthalmology, University
Medical Center, Münster, Germany.
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Yefimova MG. Myelinosome organelles in pathological retinas: ubiquitous presence and dual role in ocular proteostasis maintenance. Neural Regen Res 2022; 18:1009-1016. [PMID: 36254982 PMCID: PMC9827766 DOI: 10.4103/1673-5374.355753] [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: 01/11/2023] Open
Abstract
The timely and efficient elimination of aberrant proteins and damaged organelles, formed in response to various genetic and environmental stressors, is a vital need for all cells of the body. Recent lines of evidence point out several non-classical strategies employed by ocular tissues to cope with aberrant constituents generated in the retina and in the retinal pigmented epithelium cells exposed to various stressors. Along with conventional strategies relying upon the intracellular degradation of aberrant constituents through ubiquitin-proteasome and/or lysosome-dependent autophagy proteolysis, two non-conventional mechanisms also contribute to proteostasis maintenance in ocular tissues. An exosome-mediated clearing and a myelinosome-driven secretion mechanism do not require intracellular degradation but provide the export of aberrant constituents and "waste proteins" outside of the cells. The current review is centered on the non-degradative myelinosome-driven secretion mechanism, which operates in the retina of transgenic Huntington's disease R6/1 model mice. Myelinosome-driven secretion is supported by rare organelles myelinosomes that are detected not only in degenerative Huntington's disease R6/1 retina but also in various pathological states of the retina and of the retinal pigmented epithelium. The intra-retinal traffic and inter-cellular exchange of myelinosomes was discussed in the context of a dual role of the myelinosome-driven secretion mechanism for proteostasis maintenance in different ocular compartments. Special focus was made on the interplay between degradative and non-degradative strategies in ocular pathophysiology, to delineate potential therapeutic approaches to counteract several vision diseases.
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Affiliation(s)
- Marina G. Yefimova
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St-Petersburg, Russia,Laboratoire STIM CNRS ERL 7003, Université de Poitiers, Poitiers, France,Correspondence to: Marina G. Yefimova, .
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7
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Keeling E, Lynn SA, Koh YM, Scott JA, Kendall A, Gatherer M, Page A, Cagampang FR, Lotery AJ, Ratnayaka JA. A High Fat "Western-style" Diet Induces AMD-Like Features in Wildtype Mice. Mol Nutr Food Res 2022; 66:e2100823. [PMID: 35306732 PMCID: PMC9287010 DOI: 10.1002/mnfr.202100823] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 03/01/2022] [Indexed: 12/20/2022]
Abstract
Scope The intake of a “Western‐style” diet rich in fats is linked with developing retinopathies including age‐related macular degeneration (AMD). Wildtype mice are given a high fat diet (HFD) to determine how unhealthy foods can bring about retinal degeneration. Methods and results Following weaning, female C57BL/6 mice are maintained on standard chow (7% kcal fat, n = 29) or a HFD (45% kcal fat, n = 27) for 12 months. Animals were sacrificed following electroretinography (ERG) and their eyes analyzed by histology, confocal immunofluorescence, and transmission electron microscopy. HFD mice become obese, but showed normal retinal function compared to chow‐fed controls. However, diminished β3tubulin labeling of retinal cross‐sections indicated fewer/damaged neuronal processes in the inner plexiform layer. AMD‐linked proteins clusterin and TIMP3 accumulated in the retinal pigment epithelium (RPE) and Bruch's membrane (BrM). Neutral lipids also deposited in the outer retinae of HFD mice. Ultrastructural analysis revealed disorganized photoreceptor outer segments, collapsed/misaligned RPE microvilli, vacuoles, convoluted basolateral RPE infolds and BrM changes. Basal laminar‐like deposits were also present alongside abnormal choroidal endothelial cells. Conclusions We show that prolonged exposure to an unhealthy “Western‐style” diet alone can recapitulate early‐intermediate AMD‐like features in wildtype mice, highlighting the importance of diet and nutrition in the etiology of sight‐loss.
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Affiliation(s)
- Eloise Keeling
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, UK
| | - Savannah A Lynn
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, UK
| | - Yen Min Koh
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, UK
| | - Jenny A Scott
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, UK
| | - Aaron Kendall
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, UK
| | - Maureen Gatherer
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, UK
| | - Anton Page
- Biomedical Imaging Unit, University of Southampton, MP12, Tremona Road, Southampton, SO16 6YD, UK
| | - Felino R Cagampang
- Human Development and Health, Faculty of Medicine, University of Southampton, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK
| | - Andrew J Lotery
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, UK.,Eye Unit, University Hospital Southampton NHS Foundation Trust, Southampton, SO16 6YD, UK
| | - J Arjuna Ratnayaka
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, UK
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El-Darzi N, Mast N, Buchner DA, Saadane A, Dailey B, Trichonas G, Pikuleva IA. Low-Dose Anti-HIV Drug Efavirenz Mitigates Retinal Vascular Lesions in a Mouse Model of Alzheimer's Disease. Front Pharmacol 2022; 13:902254. [PMID: 35721135 PMCID: PMC9198296 DOI: 10.3389/fphar.2022.902254] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 05/02/2022] [Indexed: 12/02/2022] Open
Abstract
A small dose of the anti-HIV drug efavirenz (EFV) was previously discovered to activate CYP46A1, a cholesterol-eliminating enzyme in the brain, and mitigate some of the manifestation of Alzheimer's disease in 5XFAD mice. Herein, we investigated the retina of these animals, which were found to have genetically determined retinal vascular lesions associated with deposits within the retinal pigment epithelium and subretinal space. We established that EFV treatment activated CYP46A1 in the retina, enhanced retinal cholesterol turnover, and diminished the lesion frequency >5-fold. In addition, the treatment mitigated fluorescein leakage from the aberrant blood vessels, deposit size, activation of retinal macrophages/microglia, and focal accumulations of amyloid β plaques, unesterified cholesterol, and Oil Red O-positive lipids. Studies of retinal transcriptomics and proteomics identified biological processes enriched with differentially expressed genes and proteins. We discuss the mechanisms of the beneficial EFV effects on the retinal phenotype of 5XFAD mice. As EFV is an FDA-approved drug, and we already tested the safety of small-dose EFV in patients with Alzheimer's disease, our data support further clinical investigation of this drug in subjects with retinal vascular lesions or neovascular age-related macular degeneration.
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Affiliation(s)
- Nicole El-Darzi
- Departments of Ophthalmology and Visual Sciences, Cleveland, OH, United States
| | - Natalia Mast
- Departments of Ophthalmology and Visual Sciences, Cleveland, OH, United States
| | - David A. Buchner
- Departments of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, United States
| | - Aicha Saadane
- Departments of Ophthalmology and Visual Sciences, Cleveland, OH, United States
| | - Brian Dailey
- Departments of Ophthalmology and Visual Sciences, Cleveland, OH, United States
| | - Georgios Trichonas
- Departments of Ophthalmology and Visual Sciences, Cleveland, OH, United States
| | - Irina A. Pikuleva
- Departments of Ophthalmology and Visual Sciences, Cleveland, OH, United States,*Correspondence: Irina A. Pikuleva,
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Kim SY, Qian H. Comparison between sodium iodate and lipid peroxide murine models of age-related macular degeneration for drug evaluation-a narrative review. ANNALS OF EYE SCIENCE 2022; 7:8. [PMID: 37622161 PMCID: PMC10448775 DOI: 10.21037/aes-21-25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
Abstract
Objective In this review, non-transgenic models of age-related macular degeneration (AMD) are discussed, with focuses on murine retinal degeneration induced by sodium iodate and lipid peroxide (HpODE) as preclinical study platforms. Background AMD is the most common cause of vision loss in a world with an increasingly aging population. The major phenotypes of early and intermediate AMD are increased drusen and autofluorescence, Müller glia activation, infiltrated subretinal microglia and inward moving retinal pigment epithelium cells. Intermediate AMD may progress to advanced AMD, characterized by geography atrophy and/or choroidal neovascularization. Various transgenic and non-transgenic animal models related to retinal degeneration have been generated to investigate AMD pathogenesis and pathobiology, and have been widely used as potential therapeutic evaluation platforms. Methods Two retinal degeneration murine models induced by sodium iodate and HpODE are described. Distinct pathological features and procedures of these two models are compared. In addition, practical protocol and material preparation and assessment methods are elaborated. Conclusion Retina degeneration induced by sodium iodate and HpODE in mouse eye resembles many clinical aspects of human AMD and complimentary to the existent other animal models. However, standardization of procedure and assessment protocols is needed for preclinical studies. Further studies of HpODE on different routes, doses and species will be valuable for the future extensive use. Despite many merits of murine studies, differences between murine and human should be always considered.
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Affiliation(s)
- Soo-Young Kim
- Department of Pharmaceutics, Department of Biology, Virginia Commonwealth University, Richmond, VA, 23298, USA
- Center for Nanomedicine, Wilmer Eye Institute, Department of Ophthalmology, Johns Hopkins University of Medicine, Baltimore, MD, 21287, USA
| | - Haohua Qian
- Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
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Amadoro G, Latina V, Balzamino BO, Squitti R, Varano M, Calissano P, Micera A. Nerve Growth Factor-Based Therapy in Alzheimer's Disease and Age-Related Macular Degeneration. Front Neurosci 2021; 15:735928. [PMID: 34566573 PMCID: PMC8459906 DOI: 10.3389/fnins.2021.735928] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Accepted: 08/10/2021] [Indexed: 12/23/2022] Open
Abstract
Alzheimer's disease (AD) is an age-associated neurodegenerative disease which is the most common cause of dementia among the elderly. Imbalance in nerve growth factor (NGF) signaling, metabolism, and/or defect in NGF transport to the basal forebrain cholinergic neurons occurs in patients affected with AD. According to the cholinergic hypothesis, an early and progressive synaptic and neuronal loss in a vulnerable population of basal forebrain involved in memory and learning processes leads to degeneration of cortical and hippocampal projections followed by cognitive impairment with accumulation of misfolded/aggregated Aβ and tau protein. The neuroprotective and regenerative effects of NGF on cholinergic neurons have been largely demonstrated, both in animal models of AD and in living patients. However, the development of this neurotrophin as a disease-modifying therapy in humans is challenged by both delivery limitations (inability to cross the blood-brain barrier (BBB), poor pharmacokinetic profile) and unwanted side effects (pain and weight loss). Age-related macular degeneration (AMD) is a retinal disease which represents the major cause of blindness in developed countries and shares several clinical and pathological features with AD, including alterations in NGF transduction pathways. Interestingly, nerve fiber layer thinning, degeneration of retinal ganglion cells and changes of vascular parameters, aggregation of Aβ and tau protein, and apoptosis also occur in the retina of both AD and AMD. A protective effect of ocular administration of NGF on both photoreceptor and retinal ganglion cell degeneration has been recently described. Besides, the current knowledge about the detection of essential trace metals associated with AD and AMD and their changes depending on the severity of diseases, either systemic or locally detected, further pave the way for a promising diagnostic approach. This review is aimed at describing the employment of NGF as a common therapeutic approach to AMD and AD and the diagnostic power of detection of essential trace metals associated with both diseases. The multiple approaches employed to allow a sustained release/targeting of NGF to the brain and its neurosensorial ocular extensions will be also discussed, highlighting innovative technologies and future translational prospects.
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Affiliation(s)
- Giuseppina Amadoro
- Institute of Translational Pharmacology (IFT)-CNR, Rome, Italy
- European Brain Research Institute, Rome, Italy
| | | | | | - Rosanna Squitti
- Molecular Markers Laboratory, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Monica Varano
- Research Laboratories in Ophthalmology, IRCCS-Fondazione Bietti, Rome, Italy
| | | | - Alessandra Micera
- Research Laboratories in Ophthalmology, IRCCS-Fondazione Bietti, Rome, Italy
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Features of Retinal Neurogenesis as a Key Factor of Age-Related Neurodegeneration: Myth or Reality? Int J Mol Sci 2021; 22:ijms22147373. [PMID: 34298993 PMCID: PMC8303671 DOI: 10.3390/ijms22147373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/05/2021] [Accepted: 07/05/2021] [Indexed: 11/16/2022] Open
Abstract
Age-related macular degeneration (AMD) is a complex multifactorial neurodegenerative disease that constitutes the most common cause of irreversible blindness in the elderly in the developed countries. Incomplete knowledge about its pathogenesis prevents the search for effective methods of prevention and treatment of AMD, primarily of its "dry" type which is by far the most common (90% of all AMD cases). In the recent years, AMD has become "younger": late stages of the disease are now detected in relatively young people. It is known that AMD pathogenesis-according to the age-related structural and functional changes in the retina-is linked with inflammation, hypoxia, oxidative stress, mitochondrial dysfunction, and an impairment of neurotrophic support, but the mechanisms that trigger the conversion of normal age-related changes to the pathological process as well as the reason for early AMD development remain unclear. In the adult mammalian retina, de novo neurogenesis is very limited. Therefore, the structural and functional features that arise during its maturation and formation can exert long-term effects on further ontogenesis of this tissue. The aim of this review was to discuss possible contributions of the changes/disturbances in retinal neurogenesis to the early development of AMD.
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12
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Kim TH, Son T, Klatt D, Yao X. Concurrent OCT and OCT angiography of retinal neurovascular degeneration in the 5XFAD Alzheimer's disease mice. NEUROPHOTONICS 2021; 8:035002. [PMID: 34277888 PMCID: PMC8271351 DOI: 10.1117/1.nph.8.3.035002] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/25/2021] [Indexed: 05/15/2023]
Abstract
Significance: As one part of the central nervous system, the retina manifests neurovascular defects in Alzheimer's disease (AD). Quantitative imaging of retinal neurovascular abnormalities may promise a new method for early diagnosis and treatment assessment of AD. Previous imaging studies of transgenic AD mouse models have been limited to the central part of the retina. Given that the pathological hallmarks of AD frequently appear in different peripheral quadrants, a comprehensive regional investigation is needed for a better understanding of the retinal degeneration associated with AD-like pathology. Aim: We aim to demonstrate concurrent optical coherence tomography (OCT) and OCT angiography (OCTA) of retinal neuronal and vascular abnormalities in the 5XFAD mouse model and to investigate region-specific retinal degeneration. Approach: A custom-built OCT system was used for retinal imaging. Retinal thickness, vessel width, and vessel density were quantitatively measured. The artery and vein (AV) were classified for differential AV analysis, and trilaminar vascular plexuses were segmented for depth-resolved density measurement. Results: It was observed that inner and outer retinal thicknesses were explicitly reduced in the dorsal and temporal quadrants, respectively, in 5XFAD mice. A significant arterial narrowing in 5XFAD mice was also observed. Moreover, overall capillary density consistently showed a decreasing trend in 5XFAD mice, but regional specificity was not identified. Conclusions: Quadrant- and layer-specific neurovascular degeneration was observed in 5XFAD mice. Concurrent OCT and OCTA promise a noninvasive method for quantitative monitoring of AD progression and treatment assessment.
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Affiliation(s)
- Tae-Hoon Kim
- University of Illinois at Chicago, Department of Bioengineering, Chicago, Illinois, United States
| | - Taeyoon Son
- University of Illinois at Chicago, Department of Bioengineering, Chicago, Illinois, United States
| | - Dieter Klatt
- University of Illinois at Chicago, Department of Bioengineering, Chicago, Illinois, United States
| | - Xincheng Yao
- University of Illinois at Chicago, Department of Bioengineering, Chicago, Illinois, United States
- University of Illinois at Chicago, Department of Ophthalmology and Visual Sciences, Chicago, Illinois, United States
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13
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Guo L, Ravindran N, Shamsher E, Hill D, Cordeiro MF. Retinal Changes in Transgenic Mouse Models of Alzheimer's Disease. Curr Alzheimer Res 2021; 18:89-102. [PMID: 33855942 DOI: 10.2174/1567205018666210414113634] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 02/09/2021] [Accepted: 04/05/2021] [Indexed: 11/22/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder, the most common form of dementia. AD is characterised by amyloid-β (Aβ) plaques and neurofibrillary tangles (NFT) in the brain, in association with neuronal loss and synaptic failure, causing cognitive deficits. Accurate and early diagnosis is currently unavailable in lifespan, hampering early intervention of potential new treatments. Visual deficits have been well documented in AD patients, and the pathological changes identified in the brain are also believed to be found in the retina, an integral part of the central nervous system. Retinal changes can be detected by real-time non-invasive imaging, due to the transparent nature of the ocular media, potentially allowing an earlier diagnosis as well as monitoring disease progression and treatment outcome. Animal models are essential for AD research, and this review has a focus on retinal changes in various transgenic AD mouse models with retinal imaging and immunohistochemical analysis as well as therapeutic effects in those models. We also discuss the limitations of transgenic AD models in clinical translations.
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Affiliation(s)
- Li Guo
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Nivedita Ravindran
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Ehtesham Shamsher
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Daniel Hill
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - M Francesca Cordeiro
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
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14
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Retinal hyperspectral imaging in the 5xFAD mouse model of Alzheimer's disease. Sci Rep 2021; 11:6387. [PMID: 33737550 PMCID: PMC7973540 DOI: 10.1038/s41598-021-85554-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 02/20/2021] [Indexed: 11/08/2022] Open
Abstract
Hyperspectral imaging of the retina has recently been posited as a potentially useful form of spectroscopy of amyloid-beta (Aβ) protein in the eyes of those with Alzheimer's disease (AD). The concept of using the retina as a biomarker for AD is an attractive one, as current screening tools for AD are either expensive or inaccessible. Recent studies have investigated hyperspectral imaging in Aβ models however these studies have been in younger mice. Here we characterised hyperspectral reflectance profile in 6 to 17 months old 5xFAD mice and compare this to Aβ in isolated preparations. Hyperspectral imaging was conducted across two preparations of Aβ using a custom built bench ophthalmoscope. In the in vitro condition, 1 mg of purified human Aβ42 was solubilised and left to aggregate for 72 h. This soluble/insoluble Aβ mixture was then imaged by suspending the solution at a pipette tip and compared against phosphate buffered saline (PBS) control (n = 10 ROIs / group). In the in vivo condition, a 5xFAD transgenic mouse model was used and retinae were imaged at the age of 6 (n = 9), 12 (n = 9) and 17 months (n = 8) with age matched wildtype littermates as control (n = 12, n = 13, n = 15 respectively). In the vitro condition, hyperspectral imaging of the solution showed greater reflectance compared with vehicle (p < 0.01), with the greatest differences occurring in the short visible spectrum (< 500 nm). In the in vivo preparation, 5xFAD showed greater hyperspectral reflectance at all ages (6, 12, 17 months, p < 0.01). These differences were noted most in the short wavelengths at younger ages, with an additional peak appearing at longer wavelengths (~ 550 nm) with advancing age. This study shows that the presence of Aβ (soluble/insoluble mixture) can increase the hyperspectral reflectance profile in vitro as well as in vivo. Differences were evident in the short wavelength spectrum (< 500 nm) in vitro and were preserved when imaged through the ocular media in the in vivo conditions. With advancing age a second hump around ~ 550 nm became more apparent. Hyperspectral imaging of the retina does not require the use of contrast agents and is a potentially useful and non-invasive biomarker for AD.
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15
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Wang L, Mao X. Role of Retinal Amyloid-β in Neurodegenerative Diseases: Overlapping Mechanisms and Emerging Clinical Applications. Int J Mol Sci 2021; 22:2360. [PMID: 33653000 PMCID: PMC7956232 DOI: 10.3390/ijms22052360] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/23/2021] [Accepted: 02/23/2021] [Indexed: 02/03/2023] Open
Abstract
Amyloid-β (Aβ) accumulations have been identified in the retina for neurodegeneration-associated disorders like Alzheimer's disease (AD), glaucoma, and age-related macular degeneration (AMD). Elevated retinal Aβ levels were associated with progressive retinal neurodegeneration, elevated cerebral Aβ accumulation, and increased disease severity with a decline in cognition and vision. Retinal Aβ accumulation and its pathological effects were demonstrated to occur prior to irreversible neurodegeneration, which highlights its potential in early disease detection and intervention. Using the retina as a model of the brain, recent studies have focused on characterizing retinal Aβ to determine its applicability for population-based screening of AD, which warrants a further understanding of how Aβ manifests between these disorders. While current treatments directly targeting Aβ accumulations have had limited results, continued exploration of Aβ-associated pathological pathways may yield new therapeutic targets for preserving cognition and vision. Here, we provide a review on the role of retinal Aβ manifestations in these distinct neurodegeneration-associated disorders. We also discuss the recent applications of retinal Aβ for AD screening and current clinical trial outcomes for Aβ-associated treatment approaches. Lastly, we explore potential future therapeutic targets based on overlapping mechanisms of pathophysiology in AD, glaucoma, and AMD.
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Affiliation(s)
- Liang Wang
- Miller School of Medicine, University of Miami, Miami, FL 33136, USA;
| | - Xiaobo Mao
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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16
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Lynn SA, Johnston DA, Scott JA, Munday R, Desai RS, Keeling E, Weaterton R, Simpson A, Davis D, Freeman T, Chatelet DS, Page A, Cree AJ, Lee H, Newman TA, Lotery AJ, Ratnayaka JA. Oligomeric Aβ 1-42 Induces an AMD-Like Phenotype and Accumulates in Lysosomes to Impair RPE Function. Cells 2021; 10:413. [PMID: 33671133 PMCID: PMC7922851 DOI: 10.3390/cells10020413] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 02/04/2021] [Accepted: 02/11/2021] [Indexed: 12/12/2022] Open
Abstract
Alzheimer's disease-associated amyloid beta (Aβ) proteins accumulate in the outer retina with increasing age and in eyes of age-related macular degeneration (AMD) patients. To study Aβ-induced retinopathy, wild-type mice were injected with nanomolar human oligomeric Aβ1-42, which recapitulate the Aβ burden reported in human donor eyes. In vitro studies investigated the cellular effects of Aβ in endothelial and retinal pigment epithelial (RPE) cells. Results show subretinal Aβ-induced focal AMD-like pathology within 2 weeks. Aβ exposure caused endothelial cell migration, and morphological and barrier alterations to the RPE. Aβ co-localized to late-endocytic compartments of RPE cells, which persisted despite attempts to clear it through upregulation of lysosomal cathepsin B, revealing a novel mechanism of lysosomal impairment in retinal degeneration. The rapid upregulation of cathepsin B was out of step with the prolonged accumulation of Aβ within lysosomes, and contrasted with enzymatic responses to internalized photoreceptor outer segments (POS). Furthermore, RPE cells exposed to Aβ were identified as deficient in cargo-carrying lysosomes at time points that are critical to POS degradation. These findings imply that Aβ accumulation within late-endocytic compartments, as well as lysosomal deficiency, impairs RPE function over time, contributing to visual defects seen in aging and AMD eyes.
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Affiliation(s)
- Savannah A. Lynn
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - David A. Johnston
- Biomedical Imaging Unit, University of Southampton, MP12, Tremona Road, Southampton SO16 6YD, UK; (D.A.J.); (D.S.C.); (A.P.)
| | - Jenny A. Scott
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - Rosie Munday
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - Roshni S. Desai
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - Eloise Keeling
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - Ruaridh Weaterton
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - Alexander Simpson
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - Dillon Davis
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - Thomas Freeman
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - David S. Chatelet
- Biomedical Imaging Unit, University of Southampton, MP12, Tremona Road, Southampton SO16 6YD, UK; (D.A.J.); (D.S.C.); (A.P.)
| | - Anton Page
- Biomedical Imaging Unit, University of Southampton, MP12, Tremona Road, Southampton SO16 6YD, UK; (D.A.J.); (D.S.C.); (A.P.)
| | - Angela J. Cree
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - Helena Lee
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
- Eye Unit, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Tracey A. Newman
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
| | - Andrew J. Lotery
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
- Eye Unit, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - J. Arjuna Ratnayaka
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP 806, Tremona Road, Southampton SO16 6YD, UK; (S.A.L.); (J.A.S.); (R.M.); (R.S.D.); (E.K.); (R.W.); (A.S.); (D.D.); (T.F.); (A.J.C.); (H.L.); (T.A.N.); (A.J.L.)
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17
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Soundara Pandi SP, Ratnayaka JA, Lotery AJ, Teeling JL. Progress in developing rodent models of age-related macular degeneration (AMD). Exp Eye Res 2020; 203:108404. [PMID: 33340497 DOI: 10.1016/j.exer.2020.108404] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 12/13/2020] [Accepted: 12/14/2020] [Indexed: 12/25/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of irreversible central vision loss, typically affecting individuals from mid-life onwards. Its multifactorial aetiology and the lack of any effective treatments has spurred the development of animal models as research and drug discovery tools. Several rodent models have been developed which recapitulate key features of AMD and provide insights into its underlying pathology. These have contributed to making significant progress in understanding the disease and the identification of novel therapeutic targets. However, a major caveat with existing models is that they do not demonstrate the full disease spectrum. In this review, we outline advances in rodent AMD models from the last decade. These models feature various hallmarks associated with AMD, including oxidative stress, hypoxia, immune dysregulation, genetic mutations and environmental risk factors. The review summarises the methods by which each model was created, its pathological characteristics as well as its relation to the disease in humans.
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Affiliation(s)
- Sudha Priya Soundara Pandi
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, United Kingdom
| | - J Arjuna Ratnayaka
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, United Kingdom.
| | - Andrew J Lotery
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton, SO16 6YD, United Kingdom; Eye Unit, University Hospital Southampton NHS Foundation Trust, Southampton, SO16 6YD, United Kingdom.
| | - Jessica L Teeling
- Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, MP840, Tremona Road, Southampton, SO16 6YD, United Kingdom.
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18
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Kim SY, Kambhampati SP, Bhutto IA, McLeod DS, Lutty GA, Kannan RM. Evolution of oxidative stress, inflammation and neovascularization in the choroid and retina in a subretinal lipid induced age-related macular degeneration model. Exp Eye Res 2020; 203:108391. [PMID: 33307075 DOI: 10.1016/j.exer.2020.108391] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/16/2020] [Accepted: 12/05/2020] [Indexed: 01/19/2023]
Abstract
Oxidative stress, inflammation and neovascularization are the key pathological events that are implicated in human age-related macular degeneration (AMD). There are a limited number of animal models available for evaluating and developing new therapies. Most models represent late exudative or neovascular AMD (nAMD) but there is a relative paucity of models that mimic early events in AMD. The purpose of this study is to characterize the evolution of oxidative stress, inflammation, retinal degeneration and neovascularization in a rat model of AMD, created by subretinal injection of human lipid hydroperoxide (HpODE) that found in the sub-macular region in aged and AMD patients. Subretinal HpODE induced retinal pigment epithelium (RPE) and retinal degeneration resulting in loss of RPE cells, photoreceptors and retinal thinning. RPE degeneration and atrophy were detected by day 5, followed by neural tissue degeneration at day 12 with robust TUNEL positive cells. Western blot analysis confirmed an increase in pro-apoptotic Bak protein at day 12 in retinal tissues. Oxidative damage biomarkers (4-hydroxynonenal, malondialdehyde, 8-hydroxy-2'-deoxyguanosine, and nitrotyrosine) increased in retinal tissue from days 5-12. Müller glial activation was observed in the HpODE injected area at day 5 followed by its remodeling and migration in the outer retina by day 20. RT-qPCR analysis further indicated upregulation of pro-inflammatory genes (TNF-α, IL-1β and IL-6) both in retinal and RPE/choroidal tissue as early as day 2 and persisted until day 12. Upregulation of oxidative stress markers such as NADPH oxidase (NOX and DOUX family) was detected early in retinal tissue by day 2 followed by its upregulation in choroidal tissue at day 5. Neovascularization was demonstrated from day 12 to day 20 post HpODE injection in choroidal tissue. The results from this study indicate that subretinal HpODE induces advanced AMD phenotypes comprising many aspects of both dry/early and late) and neovascular/late AMD as observed in humans. Within 3 weeks via oxidative damage, upregulation of reactive oxygen species and pro-inflammatory genes, pro-apoptotic Bak and pro-angiogenic VEGF upregulation occurs leading to CNV formation. This experimental model of subretinal HpODE is an appropriate model for the study of AMD and provides an important platform for translational and basic research in developing new therapies particularly for early/dry AMD where currently no viable therapies are available.
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Affiliation(s)
- Soo-Young Kim
- Center for Nanomedicine at the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Siva P Kambhampati
- Center for Nanomedicine at the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Imran A Bhutto
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - D Scott McLeod
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Gerard A Lutty
- Center for Nanomedicine at the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Rangaramanujam M Kannan
- Center for Nanomedicine at the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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19
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Hurst J, Fietz A, Tsai T, Joachim SC, Schnichels S. Organ Cultures for Retinal Diseases. Front Neurosci 2020; 14:583392. [PMID: 33324149 PMCID: PMC7724035 DOI: 10.3389/fnins.2020.583392] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/13/2020] [Indexed: 12/18/2022] Open
Abstract
The successful development of novel therapies is closely linked with understanding the underlying pathomechanisms of a disease. To do so, model systems that reflect human diseases and allow for the evaluation of new therapeutic approaches are needed. Yet, preclinical animal studies often have limited success in predicting human physiology, pathology, and therapeutic responses. Moreover, animal testing is facing increasing ethical and bureaucratic hurdles, while human cell cultures are limited in their ability to represent in vivo situations due to the lack of the tissue microenvironment, which may alter cellular responses. To overcome these struggles, organ cultures, especially those of complex organs such as the retina, can be used to study physiological reactions to substances or stressors. Human and animal organ cultures are now well established and recognized. This mini-review discusses how retinal organ cultures can be used to preserve tissue architecture more realistically and therefore better represent disease-related changes. It also shows how molecular biological, biochemical, and histological techniques can be combined to investigate how anatomical localization may alter cellular responses. Examples for the use of retinal organ cultures, including models to study age-related macular degeneration (AMD), retinitis pigmentosa (RP), central artery occlusion (CRAO), and glaucoma are presented, and their advantages and disadvantages are discussed. We conclude that organ cultures significantly improve our understanding of complex retinal diseases and may advance treatment testing without the need for animal testing.
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Affiliation(s)
- José Hurst
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Agnes Fietz
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Teresa Tsai
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Stephanie C. Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Sven Schnichels
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
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20
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Keeling E, Chatelet DS, Tan NYT, Khan F, Richards R, Thisainathan T, Goggin P, Page A, Tumbarello DA, Lotery AJ, Ratnayaka JA. 3D-Reconstructed Retinal Pigment Epithelial Cells Provide Insights into the Anatomy of the Outer Retina. Int J Mol Sci 2020; 21:ijms21218408. [PMID: 33182490 PMCID: PMC7672636 DOI: 10.3390/ijms21218408] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 11/05/2020] [Accepted: 11/06/2020] [Indexed: 11/16/2022] Open
Abstract
The retinal pigment epithelium (RPE) is located between the neuroretina and the choroid, and plays a critical role in vision. RPE cells internalise outer segments (OS) from overlying photoreceptors in the daily photoreceptor renewal. Changes to RPE structure are linked with age and retinopathy, which has been described in the past by conventional 2D electron microscopy. We used serial block face scanning electron microscopy (SBF-SEM) to reconstruct RPE cells from the central mouse retina. Three-dimensional-reconstructed OS revealed the RPE to support large numbers of photoreceptors (90–216 per RPE cell). Larger bi-nucleate RPE maintained more photoreceptors, although their cytoplasmic volume was comparable to smaller mono-nucleate RPE supporting fewer photoreceptors. Scrutiny of RPE microvilli and interdigitating OS revealed the angle and surface area of contact between RPE and photoreceptors. Bi-nucleate RPE contained more mitochondria compared to mono-nucleate RPE. Furthermore, bi-nucleate cells contained larger sub-RPE spaces, supporting a likely association with disease. Use of perfusion-fixed tissues ensured the highest possible standard of preservation, providing novel insights into the 3D RPE architecture and changes linked with retinopathy. This study serves as a benchmark for comparing retinal tissues from donor eyes with age-related macular degeneration (AMD) and other retinopathies.
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Affiliation(s)
- Eloise Keeling
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton SO16 6YD, UK; (E.K.); (N.Y.T.T.); (F.K.); (R.R.); (T.T.); (A.J.L.)
| | - David S. Chatelet
- Biomedical Imaging Unit, University of Southampton, MP12, Tremona Road, Southampton SO16 6YD, UK; (D.S.C.); (P.G.); (A.P.)
| | - Nicole Y. T. Tan
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton SO16 6YD, UK; (E.K.); (N.Y.T.T.); (F.K.); (R.R.); (T.T.); (A.J.L.)
| | - Farihah Khan
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton SO16 6YD, UK; (E.K.); (N.Y.T.T.); (F.K.); (R.R.); (T.T.); (A.J.L.)
| | - Rhys Richards
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton SO16 6YD, UK; (E.K.); (N.Y.T.T.); (F.K.); (R.R.); (T.T.); (A.J.L.)
| | - Thibana Thisainathan
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton SO16 6YD, UK; (E.K.); (N.Y.T.T.); (F.K.); (R.R.); (T.T.); (A.J.L.)
| | - Patricia Goggin
- Biomedical Imaging Unit, University of Southampton, MP12, Tremona Road, Southampton SO16 6YD, UK; (D.S.C.); (P.G.); (A.P.)
| | - Anton Page
- Biomedical Imaging Unit, University of Southampton, MP12, Tremona Road, Southampton SO16 6YD, UK; (D.S.C.); (P.G.); (A.P.)
| | - David A. Tumbarello
- Biological Sciences, Faculty of Environmental and Life Sciences, Life Sciences Building 85, University of Southampton, Highfield Campus, Southampton SO17 1BJ, UK;
| | - Andrew J. Lotery
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton SO16 6YD, UK; (E.K.); (N.Y.T.T.); (F.K.); (R.R.); (T.T.); (A.J.L.)
- Eye Unit, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - J. Arjuna Ratnayaka
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, MP806, Tremona Road, Southampton SO16 6YD, UK; (E.K.); (N.Y.T.T.); (F.K.); (R.R.); (T.T.); (A.J.L.)
- Correspondence: ; Tel.: +44-238120-8183
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21
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Wagner N, Reinehr S, Gammel MR, Greulich A, Hurst J, Dick HB, Schnichels S, Joachim SC. Novel Porcine Retina Cultivation Techniques Provide Improved Photoreceptor Preservation. Front Neurosci 2020; 14:556700. [PMID: 33122987 PMCID: PMC7573241 DOI: 10.3389/fnins.2020.556700] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 09/07/2020] [Indexed: 12/19/2022] Open
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness in industrialized countries among people over 60 years. It has multiple triggers and risk factors, but despite intense research efforts, its pathomechanisms are currently not completely understood. AMD pathogenesis is characterized by soft drusen in Bruch’s membrane and involves the retinal pigment epithelium–Bruch’s membrane-choroid complex and adjacent structures, like photoreceptors. This study explores the potential of novel cultivation techniques to preserve photoreceptors in retinal explants to gain better insights in AMD pathology. The porcine retina explants were cultured for 4 and 8 days using three different explantation techniques, namely, control (photoreceptors facing down, touching the filter), filter (photoreceptors facing up, turned sample using a filter), and tweezers (photoreceptors facing up, turned sample using tweezers). Optical coherence tomography revealed that the tweezers method had the best capacity to limit thinning of the retinal explants. Both novel methods displayed advantages in maintaining outer segment thickness. Additionally, immunofluorescence evaluation revealed a better preservation of opsin+ cells and rhodopsin signal intensity in both novel methods, especially the tweezers method. Furthermore, RT-qPCR analysis demonstrated an upregulation of OPSIN and RHODOPSIN mRNA expression in tweezers samples at 8 days. Amacrine and bipolar cell numbers were not altered at day 4 of cultivation, while cultivation until 8 days led to reduced bipolar cell numbers. At 4 days, CALRETININ mRNA was upregulated in filter samples, but protein kinase C alpha expression was downregulated. Retinal ganglion cells were diminished in both novel techniques due to a direct physical contact with the insert. Remarkably, no difference in TUBB3 mRNA expression was detected among the techniques. Nevertheless, both novel methods exhibited an improved retention of photoreceptor cells. In conclusion, the tweezers technique was the most promising one. Due to the high homology of the porcine to the human retina, it provides a reasonable alternative to in vivo rodent models. Consequently, an adapted coculture system based on the current findings may serve as an ex vivo model suitable to analyze AMD pathomechanisms and novel therapeutic approaches.
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Affiliation(s)
- Natalie Wagner
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Sabrina Reinehr
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Maurice R Gammel
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Andrea Greulich
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - José Hurst
- University Eye Hospital, Centre for Ophthalmology, Tübingen, Germany
| | - H Burkhard Dick
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Sven Schnichels
- University Eye Hospital, Centre for Ophthalmology, Tübingen, Germany
| | - Stephanie C Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
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22
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Chibhabha F, Yaqi Y, Li F. Retinal involvement in Alzheimer's disease (AD): evidence and current progress on the non-invasive diagnosis and monitoring of AD-related pathology using the eye. Rev Neurosci 2020; 31:/j/revneuro.ahead-of-print/revneuro-2019-0119/revneuro-2019-0119.xml. [PMID: 32804680 DOI: 10.1515/revneuro-2019-0119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 06/04/2020] [Indexed: 12/22/2022]
Abstract
Alzheimer's disease (AD) is a common form of age-related dementia that mostly affects the aging population. Clinically, it is a disease characterized by impaired memory and progressive cognitive decline. Although the pathological hallmarks of AD have been traditionally described with a general confinement in the brain, recent studies have shown similar pathological changes in the retina, which is a developmental outgrowth of the forebrain. These AD-related neurodegenerative changes in the retina have been implicated to cause early visual problems in AD even before cognitive impairment becomes apparent. With recent advances in research, the commonly held view that AD-related cerebral pathology causes visual dysfunction through disruption of central visual pathways has been re-examined. Currently, several studies have already explored how AD manifests in the retina and the possibility of using the same retina as a window to non-invasively examine AD-related pathology in the brain. Non-invasive screening of AD through the retina has the potential to improve on early detection and management of the disease since the majority of AD cases are usually diagnosed very late. The purpose of this review is to provide evidence on the involvement of the retina in AD and to suggest a possible direction for future research into the non-invasive screening, diagnosis, and monitoring of AD using the retina.
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Affiliation(s)
- Fidelis Chibhabha
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou510080,China
- Department of Anatomy, Faculty of Medicine, Midlands State University, P. Bag 9055, Senga, Gweru, Zimbabwe
- and Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080,China
| | - Yang Yaqi
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou510080,China
- and Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080,China
| | - Feng Li
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou510080,China
- and Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080,China
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23
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Schnichels S, Paquet-Durand F, Löscher M, Tsai T, Hurst J, Joachim SC, Klettner A. Retina in a dish: Cell cultures, retinal explants and animal models for common diseases of the retina. Prog Retin Eye Res 2020; 81:100880. [PMID: 32721458 DOI: 10.1016/j.preteyeres.2020.100880] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 06/23/2020] [Accepted: 06/26/2020] [Indexed: 12/11/2022]
Abstract
For many retinal diseases, including age-related macular degeneration (AMD), glaucoma, and diabetic retinopathy (DR), the exact pathogenesis is still unclear. Moreover, the currently available therapeutic options are often unsatisfactory. Research designed to remedy this situation heavily relies on experimental animals. However, animal models often do not faithfully reproduce human disease and, currently, there is strong pressure from society to reduce animal research. Overall, this creates a need for improved disease models to understand pathologies and develop treatment options that, at the same time, require fewer or no experimental animals. Here, we review recent advances in the field of in vitro and ex vivo models for AMD, glaucoma, and DR. We highlight the difficulties associated with studies on complex diseases, in which both the initial trigger and the ensuing pathomechanisms are unclear, and then delineate which model systems are optimal for disease modelling. To this end, we present a variety of model systems, ranging from primary cell cultures, over organotypic cultures and whole eye cultures, to animal models. Specific advantages and disadvantages of such models are discussed, with a special focus on their relevance to putative in vivo disease mechanisms. In many cases, a replacement of in vivo research will mean that several different in vitro models are used in conjunction, for instance to analyze and validate causative molecular pathways. Finally, we argue that the analytical decomposition into appropriate cell and tissue model systems will allow making significant progress in our understanding of complex retinal diseases and may furthermore advance the treatment testing.
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Affiliation(s)
- Sven Schnichels
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Germany.
| | - François Paquet-Durand
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Germany
| | - Marina Löscher
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Germany
| | - Teresa Tsai
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Germany
| | - José Hurst
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Germany
| | - Stephanie C Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Germany
| | - Alexa Klettner
- Department of Ophthalmology, University Medical Center, University of Kiel, Kiel, Germany
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24
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Intracellular amyloid-β disrupts tight junctions of the retinal pigment epithelium via NF-κB activation. Neurobiol Aging 2020; 95:115-122. [PMID: 32795848 DOI: 10.1016/j.neurobiolaging.2020.07.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 07/07/2020] [Accepted: 07/14/2020] [Indexed: 12/16/2022]
Abstract
Drusen are focal deposits between the retinal pigment epithelium (RPE) and Bruch's membrane in the retina of patients with age-related macular degeneration. Amyloid-β is one of the important components of drusen, which leads to local inflammation. Furthermore, intracellular amyloid-β disrupts tight junctions of the RPE. However, the intracellular mechanisms linking intracellular amyloid-β and tight-junction disruption are not clear. In this study, intracellular amyloid-β oligomers activated nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65, leading to the disorganization of tight junctions of the RPE in mice after subretinal injection of amyloid-β. Amyloid-β also triggered NF-κB activation in the RPE cells in confluent culture, which was inhibited by the suppression of the advanced glycosylation end product-specific receptor. NF-κB inhibition by an IκB kinase inhibitor prevented the suppression of expression of tight-junction proteins, zonula occuludens-1 and occludin in RPE cells. In addition, tight-junction complexes remained intact in the RPE of mice with NF-κB inhibition, although there were intracellular amyloid-β oligomers. These data suggested that NF-κB inhibition might be a therapeutic approach to prevent amyloid-β-mediated tight-junction disruption.
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25
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Liu Y, Wei W, Baazaoui N, Liu F, Iqbal K. Inhibition of AMD-Like Pathology With a Neurotrophic Compound in Aged Rats and 3xTg-AD Mice. Front Aging Neurosci 2019; 11:309. [PMID: 31803044 PMCID: PMC6877482 DOI: 10.3389/fnagi.2019.00309] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 10/28/2019] [Indexed: 11/17/2022] Open
Abstract
Age-associated macular degeneration (AMD), which leads to loss of vision at its end stage, is one of the most common neurodegenerative diseases among the elderly. However, to date, no effective drug therapy is available for the prevention of AMD. Here, we report the occurrence of AMD pathology and its prevention by chronic treatment with the neurotrophic peptidergic compound P021, in aged rats and 3xTg-AD mice. We found photoreceptor degeneration, lipofuscin granules, vacuoles, and atrophy in retinal pigment epithelium (RPE) as well as Bruch’s membrane (BM) thickening; in aged rats, we even found rosette-like structure formation. Microgliosis and astrogliosis were observed in different retinal layers. In addition, we also found that total tau, phosphorylated tau, Aβ/APP, and VEGF were widely distributed in the sub-retina of aged rats and 3xTg mice. Importantly, chronic treatment with P021 for 3 months in rats and for 18 months in 3xTg mice ameliorated the pathological changes above. These findings indicate the therapeutic potential of P021 for prevention and treatment of AMD and retinal changes associated with aging and Alzheimer’s disease.
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Affiliation(s)
- Yinghua Liu
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, United States.,Department of Pharmacology, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Molecular Clinical Pharmacology, Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Wei Wei
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, United States.,Key Laboratory of State Administration of Traditional Chinese Medicine of China, Department of Pathophysiology, School of Medicine, Institute of Brain Research, Jinan University, Guangzhou, China
| | - Narjes Baazaoui
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, United States
| | - Fei Liu
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, United States
| | - Khalid Iqbal
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, United States
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26
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Elovanoids counteract oligomeric β-amyloid-induced gene expression and protect photoreceptors. Proc Natl Acad Sci U S A 2019; 116:24317-24325. [PMID: 31712409 PMCID: PMC6883841 DOI: 10.1073/pnas.1912959116] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
This study uncovers biosynthetic pathway insufficiencies of prohomeostatic/neuroprotective mediators neuroprotectin D1 and elovanoids in the retina during early pathogenesis in transgenic Alzheimer’s disease 5xFAD mouse. These changes correlate with photoreceptor cell functional impairments preceding their loss. Amyloid beta (Aβ) peptide accumulates in drusen in AMD. Thus, injecting oligomeric Aβ in wild-type mice behind the retina leads to photoreceptor cell degeneration and transcriptional disruptions including upregulation of a senescence program and of senescence-associated secretory phenotype (SASP). Similar changes take place in human retinal pigment epithelium cells in culture. Novel lipid mediators, the elovanoids, restore Aβ-peptide-induced gene expression changes and SASP secretome and, in turn, protect these cells. This study opens avenues of potential therapeutic exploration of elovanoids for AMD. The onset of neurodegenerative diseases activates inflammation that leads to progressive neuronal cell death and impairments in cognition (Alzheimer’s disease) and sight (age-related macular degeneration [AMD]). How neuroinflammation can be counteracted is not known. In AMD, amyloid β-peptide (Aβ) accumulates in subretinal drusen. In the 5xFAD retina, we found early functional deficiencies (ERG) without photoreceptor cell (PRC) death and identified early insufficiency in biosynthetic pathways of prohomeostatic/neuroprotective mediators neuroprotectin D1 (NPD1) and elovanoids (ELVs). To mimic an inflammatory milieu in wild-type mouse, we triggered retinal pigment epithelium (RPE) damage/PRC death by subretinally injected oligomeric β-amyloid (OAβ) and observed that ELVs administration counteracted their effects, protecting these cells. In addition, ELVs prevented OAβ-induced changes in gene expression engaged in senescence, inflammation, autophagy, extracellular matrix remodeling, and AMD. Moreover, as OAβ targets the RPE, we used primary human RPE cell cultures and demonstrated that OAβ caused cell damage, while ELVs protected and restored gene expression as in mouse. Our data show OAβ activates senescence as reflected by enhanced expression of p16INK4a, MMP1, p53, p21, p27, and Il-6, and of senescence-associated phenotype secretome, followed by RPE and PRC demise, and that ELVs 32 and 34 blunt these events and elicit protection. In addition, ELVs counteracted OAβ-induced expression of genes engaged in AMD, autophagy, and extracellular matrix remodeling. Overall, our data uncovered that ELVs downplay OAβ-senescence program induction and inflammatory transcriptional events and protect RPE cells and PRC, and therefore have potential as a possible therapeutic avenue for AMD.
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27
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Toms M, Burgoyne T, Tracey-White D, Richardson R, Dubis AM, Webster AR, Futter C, Moosajee M. Phagosomal and mitochondrial alterations in RPE may contribute to KCNJ13 retinopathy. Sci Rep 2019; 9:3793. [PMID: 30846767 PMCID: PMC6405871 DOI: 10.1038/s41598-019-40507-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 02/18/2019] [Indexed: 12/29/2022] Open
Abstract
Mutations in KCNJ13 are associated with two retinal disorders; Leber congenital amaurosis (LCA) and snowflake vitreoretinal degeneration (SVD). We examined the retina of kcnj13 mutant zebrafish (obelixtd15, c.502T > C p.[Phe168Leu]) to provide new insights into the pathophysiology underlying these conditions. Detailed phenotyping of obelixtd15 fish revealed a late onset retinal degeneration at 12 months. Electron microscopy of the obelixtd15 retinal pigment epithelium (RPE) uncovered reduced phagosome clearance and increased mitochondrial number and size prior any signs of retinal degeneration. Melanosome distribution was also affected in dark-adapted 12-month obelixtd15 fish. At 6 and 12 months, ATP levels were found to be reduced along with increased expression of glial fibrillary acidic protein and heat shock protein 60. Quantitative RT-PCR of polg2, fis1, opa1, sod1/2 and bcl2a from isolated retina showed expression changes consistent with altered mitochondrial activity and retinal stress. We propose that the retinal disease in this model is primarily a failure of phagosome physiology with a secondary mitochondrial dysfunction. Our findings suggest that alterations in the RPE and photoreceptor cellular organelles may contribute to KCNJ13-related retinal degeneration and provide a therapeutic target.
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Affiliation(s)
- Maria Toms
- UCL Institute of Ophthalmology, London, UK
| | | | | | | | - Adam M Dubis
- UCL Institute of Ophthalmology, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Andrew R Webster
- UCL Institute of Ophthalmology, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | | | - Mariya Moosajee
- UCL Institute of Ophthalmology, London, UK. .,Moorfields Eye Hospital NHS Foundation Trust, London, UK. .,Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.
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28
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Liu YH, Mölzer C, Milne GC, Kuffová L, Forrester JV. Transmission Electron Microscopy Data on drusen-like deposits in the retinal degeneration sTg-IRBP: HEL mouse model. Data Brief 2018; 22:140-144. [PMID: 30581918 PMCID: PMC6299122 DOI: 10.1016/j.dib.2018.12.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 11/20/2018] [Accepted: 12/03/2018] [Indexed: 11/15/2022] Open
Abstract
Histology (H&E) and transmission electron microscopy (TEM) data are provided showing age-related changes in the retinal structure of sTg-IRBP:HEL mice. These include substantial photoreceptor loss, atrophy of the retinal pigment epithelium, Bruch׳s membrane disruption and thickening, along with the presence of drusenoid deposits and changes in basal laminar infoldings. These features resemble some of those key characteristics found in the course of human dry (atrophic) age-related macular degeneration (AMD), particularly with regard to drusen. Hence, we believe the sTg-IRBP:HEL mouse model represents a useful and promising archetype for future study of the mechanism of drusen formation in AMD.
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Affiliation(s)
- Yi-Hsia Liu
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Christine Mölzer
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Gillian C Milne
- Microscopy and Histology Core Facility, University of Aberdeen, Aberdeen, UK
| | - Lucia Kuffová
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK.,Department of Ophthalmology, NHS Grampian, Aberdeen, UK
| | - John V Forrester
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK.,University of Western Australia, Lions Eye Institute, Perth, Australia
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