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Brar AS, Parameswarappa DC, Takkar B, Narayanan R, Jalali S, Mandal S, Fujinami K, Padhy SK. Gene Therapy for Inherited Retinal Diseases: From Laboratory Bench to Patient Bedside and Beyond. Ophthalmol Ther 2024; 13:21-50. [PMID: 38113023 PMCID: PMC10776519 DOI: 10.1007/s40123-023-00862-2] [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: 09/03/2023] [Accepted: 11/23/2023] [Indexed: 12/21/2023] Open
Abstract
This comprehensive review provides a thorough examination of inherited retinal diseases (IRDs), encompassing their classification, genetic underpinnings, and the promising landscape of gene therapy trials. IRDs, a diverse group of genetic conditions causing vision loss through photoreceptor cell death, are explored through various angles, including inheritance patterns, gene involvement, and associated systemic disorders. The focal point is gene therapy, which offers hope for halting or even reversing the progression of IRDs. The review highlights ongoing clinical trials spanning retinal cell replacement, neuroprotection, pharmacological interventions, and optogenetics. While these therapies hold tremendous potential, they face challenges like timing optimization, standardized assessment criteria, inflammation management, vector refinement, and raising awareness among vision scientists. Additionally, translating gene therapy success into widespread adoption and addressing cost-effectiveness are crucial challenges to address. Continued research and clinical trials are essential to fully harness gene therapy's potential in treating IRDs and enhancing the lives of affected individuals.
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Affiliation(s)
- Anand Singh Brar
- Anant Bajaj Retina Institute, LV Prasad Eye Institute, Mithu Tulsi Chanrai Campus, Bhubaneswar, 751024, India
| | - Deepika C Parameswarappa
- Anant Bajaj Retina Institute, LV Prasad Eye Institute, Kallam Anji Reddy Campus, Hyderabad, 500034, India
| | - Brijesh Takkar
- Anant Bajaj Retina Institute, LV Prasad Eye Institute, Kallam Anji Reddy Campus, Hyderabad, 500034, India
| | - Raja Narayanan
- Anant Bajaj Retina Institute, LV Prasad Eye Institute, Kallam Anji Reddy Campus, Hyderabad, 500034, India
| | - Subhadra Jalali
- Anant Bajaj Retina Institute, LV Prasad Eye Institute, Kallam Anji Reddy Campus, Hyderabad, 500034, India
| | - Sohini Mandal
- Dr Rajendra Prasad Center for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Kaoru Fujinami
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, 152-8902, Japan
| | - Srikanta Kumar Padhy
- Anant Bajaj Retina Institute, LV Prasad Eye Institute, Mithu Tulsi Chanrai Campus, Bhubaneswar, 751024, India.
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Marino R, Sappington R, Feligioni M. Retinoprotective compounds, current efficacy, and future prospective. Neural Regen Res 2023; 18:2619-2622. [PMID: 37449599 DOI: 10.4103/1673-5374.373662] [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: 07/18/2023] Open
Abstract
Retinal dysfunction is the most common cause of vision loss in several retinal disorders. It has been estimated a great increase in these pathologies that are becoming more globally widespread and numerous over time, also supported by the life expectancy increment. Among different types of retinopathies, we can account some that share causes, symptoms, and treatment including diabetic retinopathy, age-related macular degeneration, glaucoma, and retinitis pigmentosa. Molecular changes, environmental factors, and genetic predisposition might be some of the main causes that drive retinal tissue to chronic inflammation and neurodegeneration in these retinopathies. The treatments available on the market contain compounds that efficiently ameliorate some of the important clinical features of these pathologies like stabilization of the intraocular pressure, reduction of eye inflammation, control of eye oxidative stress which are considered the major molecular mechanisms related to retinal dysfunction. Indeed, the most commonly used drugs are anti-inflammatories, such as corticosteroids, antioxidant, hypotonic molecules and natural neuroprotective compounds. Unfortunately, these drugs, which are fundamental to treating disease symptoms, are not capable to cure the pathologies and so they are not life-changing for patients. This review provided an overview of current treatments on the market, but more interestingly, wants to be a quick window on the new treatments that are now in clinical trials. Additionally, it has been here highlighted that the recent technical enhancement of the investigation methods to identify the various retinopathies causes might be used as a sort of "precise medicine" approach to tailor the identification of molecular pathways involved and potentially study a dedicated treatment for each patient. This approach includes the use of cutting-edge technologies like gene therapy and metabolomics.
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Affiliation(s)
- Rachele Marino
- Laboratory of Neuronal Cell Signaling, EBRI Rita Levi-Montalcini Foundation, Rome, Italy
| | - Rebecca Sappington
- Department of Neurobiology and Anatomy, Wake Forest School of Medicine, Atrium Health Wake Forest Baptist Medical Center; Department of Ophthalmology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Marco Feligioni
- Laboratory of Neuronal Cell Signaling, EBRI Rita Levi-Montalcini Foundation, Rome; Department of Neurorehabilitation Sciences, Casa di Cura Igea, Milan, Italy
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Lozano B LL, Cervantes A LA. Development of experimental treatments for patients with retinitis pigmentosa. ARCHIVOS DE LA SOCIEDAD ESPANOLA DE OFTALMOLOGIA 2023; 98:646-655. [PMID: 37640142 DOI: 10.1016/j.oftale.2023.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 08/11/2023] [Indexed: 08/31/2023]
Abstract
Retinitis pigmentosa (RP) is a group of inherited diseases that lead to degeneration of the retina and decreased vision. The World Health Organization reports around 1,300 million people affected by some type of visual impairment worldwide. The prevalence is 1 in every 4000 inhabitants and it is the first cause of blindness of genetic origin, frequent in men with a percentage of 60% and 40% in women. There is a lack of information on this pathology in the world, mainly on the existing treatments for this disease, so this bibliographic review aims to update the existing or under-study treatments and inform the limitations of each of these therapies. This review of scientific literature was carried out by consulting databases such as PubMed and Web of science, the search will be limited to articles from the years 2018-2022. There are several types of therapy in studies: gene therapy, transcorneal electrical stimulation, use of neuroprotectors, optogenic therapy, stem cell transplants and oligonucleotide therapy, which will be discussed in this article, both their benefits and the existing barriers in each treatment experimental. In conclusion, each of these therapies promises a viable treatment in the future for selective groups of people with retinitis pigmentosa, however, some therapies have shown benefit at the beginning of the disease, losing their efficacy in the long term.
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Affiliation(s)
- L L Lozano B
- Universidad Católica de Cuenca, Cuenca, Ecuador.
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Honisch C, Rodella U, Gatto C, Ruzza P, Tóthová JD. Oxidative Stress and Antioxidant-Based Interventional Medicine in Ophthalmology. Pharmaceuticals (Basel) 2023; 16:1146. [PMID: 37631061 PMCID: PMC10458870 DOI: 10.3390/ph16081146] [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: 07/21/2023] [Revised: 08/07/2023] [Accepted: 08/10/2023] [Indexed: 08/27/2023] Open
Abstract
The different anatomical compartments of the eye are highly subjected to reactive oxygen species (ROS) generation due to internal factors, such as metabolic high oxygen consumption, as well as environmental factors, including UV light. An antioxidant defense system is endowed in the eye tissues to regulate ROS quantity and activity. When this homeostatic system is overwhelmed, oxidative stress occurs, causing cellular damage, chronic inflammation, and tissue degeneration. It also plays a significant role in the development and progression of various ocular diseases. Understanding the mechanisms underlying oxidative stress in ocular conditions is thus crucial for the development of effective prevention and treatment strategies. To track marketed products based on antioxidant substances as active ingredients, the databases of the European Medicines Agency and the U.S. Food and Drug Administration were consulted. Only a limited number of items were identified, which were either used as therapeutic treatment or during ocular surgery, including antioxidants, synthetical derivatives, or pro-drugs designed to enhance tissue permeation and activity. This review aims to provide an overview of the primary ocular pathologies associated with oxidative stress and of the available pharmacological interventions centered around antioxidant molecules. Such insights are essential for advancing the development of effective prevention and novel treatment approaches.
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Affiliation(s)
- Claudia Honisch
- Institute of Biomolecular Chemistry of CNR (ICB-CNR), Via F. Marzolo, 1, 35131 Padova, Italy;
| | - Umberto Rodella
- Research and Development, AL.CHI.MI.A. S.R.L., Viale Austria, 14, 35020 Ponte San Nicolờ, Italy; (U.R.); (C.G.)
- Fondazione Banca degli Occhi del Veneto (FBOV), Via Paccagnella, 11, 30174 Zelarino, Italy
| | - Claudio Gatto
- Research and Development, AL.CHI.MI.A. S.R.L., Viale Austria, 14, 35020 Ponte San Nicolờ, Italy; (U.R.); (C.G.)
| | - Paolo Ruzza
- Institute of Biomolecular Chemistry of CNR (ICB-CNR), Via F. Marzolo, 1, 35131 Padova, Italy;
| | - Jana D’Amato Tóthová
- Research and Development, AL.CHI.MI.A. S.R.L., Viale Austria, 14, 35020 Ponte San Nicolờ, Italy; (U.R.); (C.G.)
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Das A, Imanishi Y. Drug Discovery Strategies for Inherited Retinal Degenerations. BIOLOGY 2022; 11:1338. [PMID: 36138817 PMCID: PMC9495580 DOI: 10.3390/biology11091338] [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] [Received: 08/04/2022] [Revised: 08/31/2022] [Accepted: 09/07/2022] [Indexed: 12/03/2022]
Abstract
Inherited retinal degeneration is a group of blinding disorders afflicting more than 1 in 4000 worldwide. These disorders frequently cause the death of photoreceptor cells or retinal ganglion cells. In a subset of these disorders, photoreceptor cell death is a secondary consequence of retinal pigment epithelial cell dysfunction or degeneration. This manuscript reviews current efforts in identifying targets and developing small molecule-based therapies for these devastating neuronal degenerations, for which no cures exist. Photoreceptors and retinal ganglion cells are metabolically demanding owing to their unique structures and functional properties. Modulations of metabolic pathways, which are disrupted in most inherited retinal degenerations, serve as promising therapeutic strategies. In monogenic disorders, great insights were previously obtained regarding targets associated with the defective pathways, including phototransduction, visual cycle, and mitophagy. In addition to these target-based drug discoveries, we will discuss how phenotypic screening can be harnessed to discover beneficial molecules without prior knowledge of their mechanisms of action. Because of major anatomical and biological differences, it has frequently been challenging to model human inherited retinal degeneration conditions using small animals such as rodents. Recent advances in stem cell-based techniques are opening new avenues to obtain pure populations of human retinal ganglion cells and retinal organoids with photoreceptor cells. We will discuss concurrent ideas of utilizing stem-cell-based disease models for drug discovery and preclinical development.
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Affiliation(s)
- Arupratan Das
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Yoshikazu Imanishi
- Department of Ophthalmology, Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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Tolentino MJ, Tolentino AJ. Investigational drugs in clinical trials for macular degeneration. Expert Opin Investig Drugs 2022; 31:1067-1085. [PMID: 35962560 DOI: 10.1080/13543784.2022.2113375] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Intravitreal anti-vascular endothelial growth factor (VEGF) injections for exudative age-related macular degeneration (eAMD) are effective and safe but require frequent injections and have nonresponding patients. Geographic atrophy/dry AMD (gaAMD) remains an unmet medical need . New therapies are needed to address this leading cause of blindness in the increasing aged population. AREAS COVERED This paper reviews the pathogenesis of macular degeneration, current and failed therapeutics, therapies undergoing clinical trials and a rationale for why certain AMD therapies may succeed or fail . EXPERT OPINION VEGF- inhibitors reduce both vascular leakage and neovascularization. Experimental therapies that only address neovascularization or leakage will unlikely supplant anti-VEGF therapies. The most promising future therapies for eAMD, are those that target, more potently inhibit and have a more sustained effect on the VEGF pathway such as KSI-301, RGX-314, CLS-AX, EYEP-1901, OTX-TKI. GaAMD is a phenotype of phagocytic retinal cell loss. Inhibiting phagocytic activity of retinal microglial/macrophages at the border of GA and reducing complement derived activators of microglial/macrophage is the most promising strategy. Complement inhibitors (Pegcetacoplan and Avacincaptad pegol) will likely obtain FDA approval but will serve to pave the way for combined complement and direct phagocytic inhibitors such as AVD-104.
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Affiliation(s)
- Michael J Tolentino
- University of Central Florida, FL, USA.,Blue Ocean Clinical Research, Lakeland, FL, USA.,Aviceda Therapeutics, Cambridge, MA, USA
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Fabre M, Mateo L, Lamaa D, Baillif S, Pagès G, Demange L, Ronco C, Benhida R. Recent Advances in Age-Related Macular Degeneration Therapies. Molecules 2022; 27:molecules27165089. [PMID: 36014339 PMCID: PMC9414333 DOI: 10.3390/molecules27165089] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 08/03/2022] [Accepted: 08/04/2022] [Indexed: 11/16/2022] Open
Abstract
Age-related macular degeneration (AMD) was described for the first time in the 1840s and is currently the leading cause of blindness for patients over 65 years in Western Countries. This disease impacts the eye’s posterior segment and damages the macula, a retina section with high levels of photoreceptor cells and responsible for the central vision. Advanced AMD stages are divided into the atrophic (dry) form and the exudative (wet) form. Atrophic AMD consists in the progressive atrophy of the retinal pigment epithelium (RPE) and the outer retinal layers, while the exudative form results in the anarchic invasion by choroidal neo-vessels of RPE and the retina. This invasion is responsible for fluid accumulation in the intra/sub-retinal spaces and for a progressive dysfunction of the photoreceptor cells. To date, the few existing anti-AMD therapies may only delay or suspend its progression, without providing cure to patients. However, in the last decade, an outstanding number of research programs targeting its different aspects have been initiated by academics and industrials. This review aims to bring together the most recent advances and insights into the mechanisms underlying AMD pathogenicity and disease evolution, and to highlight the current hypotheses towards the development of new treatments, i.e., symptomatic vs. curative. The therapeutic options and drugs proposed to tackle these mechanisms are analyzed and critically compared. A particular emphasis has been given to the therapeutic agents currently tested in clinical trials, whose results have been carefully collected and discussed whenever possible.
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Affiliation(s)
- Marie Fabre
- Institut de Chimie de Nice UMR 7272, Université Côte d’Azur, CNRS, 06108 Nice, France
| | - Lou Mateo
- Institut de Chimie de Nice UMR 7272, Université Côte d’Azur, CNRS, 06108 Nice, France
| | - Diana Lamaa
- CiTCoM, UMR 8038 CNRS, Faculté de Pharmacie, Université de Paris Cité, 4, Avenue de l’Observatoire, 75006 Paris, France
| | - Stéphanie Baillif
- Ophthalmology Department, University Hospital of Nice, 30 Avenue De La Voie Romaine, 06000 Nice, France
| | - Gilles Pagès
- Institute for Research on Cancer and Aging (IRCAN), UMR 7284 and INSERM U 1081, Université Côte d’Azur, CNRS 28 Avenue de Valombrose, 06107 Nice, France
| | - Luc Demange
- Institut de Chimie de Nice UMR 7272, Université Côte d’Azur, CNRS, 06108 Nice, France
- CiTCoM, UMR 8038 CNRS, Faculté de Pharmacie, Université de Paris Cité, 4, Avenue de l’Observatoire, 75006 Paris, France
- Correspondence: (L.D.); (C.R.); (R.B.)
| | - Cyril Ronco
- Institut de Chimie de Nice UMR 7272, Université Côte d’Azur, CNRS, 06108 Nice, France
- Correspondence: (L.D.); (C.R.); (R.B.)
| | - Rachid Benhida
- Institut de Chimie de Nice UMR 7272, Université Côte d’Azur, CNRS, 06108 Nice, France
- Department of Chemical and Biochemical Sciences-Green Process Engineering (CBS-GPE), Mohamed VI Polytechnic University (UM6P), Benguerir 43150, Morocco
- Correspondence: (L.D.); (C.R.); (R.B.)
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Golczak M, Moise AR, von Lintig J. Expression and biochemical analyses of proteins involved in the transport of carotenoids and retinoids. Methods Enzymol 2022; 674:447-480. [DOI: 10.1016/bs.mie.2022.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Shi J, Xu K, Hu JP, Xie Y, Zhang X, Zhang XH, Jin ZB, Li Y. Clinical Features and Natural History in a Cohort of Chinese Patients with RPE65-Associated Inherited Retinal Dystrophy. J Clin Med 2021; 10:jcm10225229. [PMID: 34830511 PMCID: PMC8625455 DOI: 10.3390/jcm10225229] [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: 09/19/2021] [Revised: 10/26/2021] [Accepted: 11/04/2021] [Indexed: 11/24/2022] Open
Abstract
RPE65-associated inherited retinal dystrophy (RPE65-IRD) is an early-onset retinal degeneration. The aim of this study was to describe the clinical features and natural course of this disease in a Chinese patient cohort with RPE65 biallelic variants. Thirty patients from 29 unrelated families with biallelic disease-causing RPE65 variants underwent full ophthalmic examinations. Thirteen were followed up over time. An additional 57 Chinese cases from 49 families were retrieved from the literature to analyze the relationship between best-corrected visual acuity (BCVA) and age. Our 30 patients presented age-dependent phenotypic characteristics. Multiple white dots were a clinical feature of young patients, while maculopathy, epiretinal membrane, and bone spicules were common in adult patients. Among the 84 patients, BCVA declined with age in a nonlinear, positive-acceleration relationship (p < 0.001). All patients older than 40 years met the WHO standard for low vision. Longitudinal observation revealed a slower visual acuity loss in patients younger than 20 years than those in their third or fourth decade of life. Our study detailed the clinical features and natural course of disease in Chinese patients with RPE65-IRD. Our results indicated that these patients have a relatively stable BCVA in childhood and adolescence, but eyesight deteriorates rapidly in the third decade of life. These findings may facilitate the implementation of gene therapy in China.
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Affiliation(s)
| | | | | | | | | | | | - Zi-Bing Jin
- Correspondence: (Z.-B.J.); (Y.L.); Tel.: +86-10-58-265-915 (Y.L.); Fax: +86-10-65-288-561 (Z.-B.J.); +65-130-796 (Y.L.)
| | - Yang Li
- Correspondence: (Z.-B.J.); (Y.L.); Tel.: +86-10-58-265-915 (Y.L.); Fax: +86-10-65-288-561 (Z.-B.J.); +65-130-796 (Y.L.)
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10
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Huang D, Heath Jeffery RC, Aung-Htut MT, McLenachan S, Fletcher S, Wilton SD, Chen FK. Stargardt disease and progress in therapeutic strategies. Ophthalmic Genet 2021; 43:1-26. [PMID: 34455905 DOI: 10.1080/13816810.2021.1966053] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Background: Stargardt disease (STGD1) is an autosomal recessive retinal dystrophy due to mutations in ABCA4, characterized by subretinal deposition of lipofuscin-like substances and bilateral centrifugal vision loss. Despite the tremendous progress made in the understanding of STGD1, there are no approved treatments to date. This review examines the challenges in the development of an effective STGD1 therapy.Materials and Methods: A literature review was performed through to June 2021 summarizing the spectrum of retinal phenotypes in STGD1, the molecular biology of ABCA4 protein, the in vivo and in vitro models used to investigate the mechanisms of ABCA4 mutations and current clinical trials.Results: STGD1 phenotypic variability remains an challenge for clinical trial design and patient selection. Pre-clinical development of therapeutic options has been limited by the lack of animal models reflecting the diverse phenotypic spectrum of STDG1. Patient-derived cell lines have facilitated the characterization of splice mutations but the clinical presentation is not always predicted by the effect of specific mutations on retinoid metabolism in cellular models. Current therapies primarily aim to delay vision loss whilst strategies to restore vision are less well developed.Conclusions: STGD1 therapy development can be accelerated by a deeper understanding of genotype-phenotype correlations.
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Affiliation(s)
- Di Huang
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Western Australia, Australia.,Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), the University of Western Australia, Nedlands, Western Australia, Australia.,Perron Institute for Neurological and Translational Science & the University of Western Australia, Nedlands, Western Australia, Australia
| | - Rachael C Heath Jeffery
- Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), the University of Western Australia, Nedlands, Western Australia, Australia
| | - May Thandar Aung-Htut
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Western Australia, Australia.,Perron Institute for Neurological and Translational Science & the University of Western Australia, Nedlands, Western Australia, Australia
| | - Samuel McLenachan
- Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), the University of Western Australia, Nedlands, Western Australia, Australia
| | - Sue Fletcher
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Western Australia, Australia.,Perron Institute for Neurological and Translational Science & the University of Western Australia, Nedlands, Western Australia, Australia
| | - Steve D Wilton
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Western Australia, Australia.,Perron Institute for Neurological and Translational Science & the University of Western Australia, Nedlands, Western Australia, Australia
| | - Fred K Chen
- Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), the University of Western Australia, Nedlands, Western Australia, Australia.,Australian Inherited Retinal Disease Registry and DNA Bank, Department of Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia.,Department of Ophthalmology, Royal Perth Hospital, Perth, Western Australia, Australia.,Department of Ophthalmology, Perth Children's Hospital, Nedlands, Western Australia, Australia
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11
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Asahi MG, Avaylon J, Wallsh J, Gallemore RP. Emerging biological therapies for the treatment of age-related macular degeneration. Expert Opin Emerg Drugs 2021; 26:193-207. [PMID: 34030572 DOI: 10.1080/14728214.2021.1931120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
INTRODUCTION Age-related macular degeneration (AMD) is the leading cause of blindness in individuals over age 50 in developed countries. Current therapy for nonexudative AMD (neAMD) is aimed at modifying risk factors and vitamin supplementation to slow progression, while intravitreal anti-vascular endothelial factor (VEGF) injections are the mainstay for treatment of choroidal neovascularization in exudative AMD (eAMD). AREAS COVERED Over the past decade, promising therapies have emerged that aim to improve the current standard of care for both diseases. Clinical trials for neAMD are investigating targets in the complement cascade, vitamin A metabolism, metformin, and tetracycline, whereas clinical trials for eAMD are aiming to decrease treatment burden through novel port delivery systems, increasing drug half-life, and targeting new sites of the VEGF cascade. Stem cell and gene therapy are also being evaluated for treatment of neAMD and eAMD. EXPERT OPINION With an aging population, the need for effective, long term, low burden treatment options for AMD will be in increasingly high demand. Current investigations aim to address the shortcomings of current treatment options with breakthrough treatment approaches. Therapeutics in the pipeline hold promise for improving the treatment of AMD, and are on track for widespread use within the next decade.
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Affiliation(s)
- Masumi G Asahi
- Department of Ophthalmology, George Washington University, Washington, DC, USA
| | - Jaycob Avaylon
- California Northstate University, College of Medicine, Elk Grove, CA, USA
| | - Josh Wallsh
- Department of Ophthalmology, Albany Medical College, Albany, NY, USA
| | - Ron P Gallemore
- Retina Macula Institute, Torrance, CA, USA.,Jules Eye Institute, University of California, Los Angeles, Los Angeles, USA
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12
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Zhang Q, Presswalla F, Ali RR, Zacks DN, Thompson DA, Miller JML. Pharmacologic activation of autophagy without direct mTOR inhibition as a therapeutic strategy for treating dry macular degeneration. Aging (Albany NY) 2021; 13:10866-10890. [PMID: 33872219 PMCID: PMC8109132 DOI: 10.18632/aging.202974] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 03/13/2021] [Indexed: 12/15/2022]
Abstract
Dry age-related macular degeneration (AMD) is marked by the accumulation of extracellular and intracellular lipid-rich deposits within and around the retinal pigment epithelium (RPE). Inducing autophagy, a conserved, intracellular degradative pathway, is a potential treatment strategy to prevent disease by clearing these deposits. However, mTOR inhibition, the major mechanism for inducing autophagy, disrupts core RPE functions. Here, we screened autophagy inducers that do not directly inhibit mTOR for their potential as an AMD therapeutic in primary human RPE culture. Only two out of more than thirty autophagy inducers tested reliably increased autophagy flux in RPE, emphasizing that autophagy induction mechanistically differs across distinct tissues. In contrast to mTOR inhibitors, these compounds preserved RPE health, and one inducer, the FDA-approved compound flubendazole (FLBZ), reduced the secretion of apolipoprotein that contributes to extracellular deposits termed drusen. Simultaneously, FLBZ increased production of the lipid-degradation product β-hydroxybutyrate, which is used by photoreceptor cells as an energy source. FLBZ also reduced the accumulation of intracellular deposits, termed lipofuscin, and alleviated lipofuscin-induced cellular senescence and tight-junction disruption. FLBZ triggered compaction of lipofuscin-like granules into a potentially less toxic form. Thus, induction of RPE autophagy without direct mTOR inhibition is a promising therapeutic approach for dry AMD.
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Affiliation(s)
- Qitao Zhang
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
| | - Feriel Presswalla
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
| | - Robin R. Ali
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
- KCL Centre for Cell and Gene Therapy, London, England WC2R 2LS, United Kingdom
| | - David N. Zacks
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
| | - Debra A. Thompson
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48105, USA
| | - Jason ML. Miller
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA
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Michalakis S, Gerhardt M, Rudolph G, Priglinger S, Priglinger C. Gene Therapy for Inherited Retinal Disorders: Update on Clinical Trials. Klin Monbl Augenheilkd 2021; 238:272-281. [PMID: 33784790 DOI: 10.1055/a-1384-0818] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Within the last decade, continuous advances in molecular biological techniques have made it possible to develop causative therapies for inherited retinal disorders (IRDs). Some of the most promising options are gene-specific approaches using adeno-associated virus-based vectors to express a healthy copy of the disease-causing gene in affected cells of a patient. This concept of gene supplementation therapy is already advocated for the treatment of retinal dystrophy in RPE65-linked Leber's congenital amaurosis (LCA) patients. While the concept of gene supplementation therapy can be applied to treat autosomal recessive and X-linked forms of IRD, it is not sufficient for autosomal dominant IRDs, where the pathogenic gene product needs to be removed. Therefore, for autosomal dominant IRDs, alternative approaches that utilize CRISPR/Cas9 or antisense oligonucleotides to edit or deplete the mutant allele or gene product are needed. In recent years, research retinal gene therapy has intensified and promising approaches for various forms of IRD are currently in preclinical and clinical development. This review article provides an overview of current clinical trials for the treatment of IRDs.
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Affiliation(s)
| | - Maximilian Gerhardt
- Department of Ophthalmology, University Hospital, LMU Munich, München, Germany
| | - Günter Rudolph
- Department of Ophthalmology, University Hospital, LMU Munich, München, Germany
| | | | - Claudia Priglinger
- Department of Ophthalmology, University Hospital, LMU Munich, München, Germany
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14
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Daich Varela M, Cabral de Guimaraes TA, Georgiou M, Michaelides M. Leber congenital amaurosis/early-onset severe retinal dystrophy: current management and clinical trials. Br J Ophthalmol 2021; 106:445-451. [PMID: 33712480 PMCID: PMC8961750 DOI: 10.1136/bjophthalmol-2020-318483] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 01/18/2021] [Accepted: 02/23/2021] [Indexed: 12/26/2022]
Abstract
Leber congenital amaurosis (LCA) is a severe congenital/early-onset retinal dystrophy. Given its monogenic nature and the immunological and anatomical privileges of the eye, LCA has been particularly targeted by cutting-edge research. In this review, we describe the current management of LCA, and highlight the clinical trials that are on-going and planned. RPE65-related LCA pivotal trials, which culminated in the first Food and Drug Administration-approved and European Medicines Agency-approved ocular gene therapy, have paved the way for a new era of genetic treatments in ophthalmology. At present, multiple clinical trials are available worldwide applying different techniques, aiming to achieve better outcomes and include more genes and variants. Genetic therapy is not only implementing gene supplementation by the use of adeno-associated viral vectors, but also clustered regularly interspaced short palindromic repeats (CRISPR)-mediated gene editing and post-transcriptional regulation through antisense oligonucleotides. Pharmacological approaches intending to decrease photoreceptor degeneration by supplementing 11-cis-retinal and cell therapy’s aim to replace the retinal pigment epithelium, providing a trophic and metabolic retinal structure, are also under investigation. Furthermore, optoelectric devices and optogenetics are also an option for patients with residual visual pathway. After more than 10 years since the first patient with LCA received gene therapy, we also discuss future challenges, such as the overlap between different techniques and the long-term durability of efficacy. The next 5 years are likely to be key to whether genetic therapies will achieve their full promise, and whether stem cell/cellular therapies will break through into clinical trial evaluation.
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Affiliation(s)
- Malena Daich Varela
- UCL Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital NHS Foundation Trust, London, London, UK
| | | | - Michalis Georgiou
- UCL Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital NHS Foundation Trust, London, London, UK
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital NHS Foundation Trust, London, London, UK
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15
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Kiser PD, Palczewski K. Pathways and disease-causing alterations in visual chromophore production for vertebrate vision. J Biol Chem 2021; 296:100072. [PMID: 33187985 PMCID: PMC7948990 DOI: 10.1074/jbc.rev120.014405] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 11/12/2020] [Accepted: 11/13/2020] [Indexed: 12/14/2022] Open
Abstract
All that we view of the world begins with an ultrafast cis to trans photoisomerization of the retinylidene chromophore associated with the visual pigments of rod and cone photoreceptors. The continual responsiveness of these photoreceptors is then sustained by regeneration processes that convert the trans-retinoid back to an 11-cis configuration. Recent biochemical and electrophysiological analyses of the retinal G-protein-coupled receptor (RGR) suggest that it could sustain the responsiveness of photoreceptor cells, particularly cones, even under bright light conditions. Thus, two mechanisms have evolved to accomplish the reisomerization: one involving the well-studied retinoid isomerase (RPE65) and a second photoisomerase reaction mediated by the RGR. Impairments to the pathways that transform all-trans-retinal back to 11-cis-retinal are associated with mild to severe forms of retinal dystrophy. Moreover, with age there also is a decline in the rate of chromophore regeneration. Both pharmacological and genetic approaches are being used to bypass visual cycle defects and consequently mitigate blinding diseases. Rapid progress in the use of genome editing also is paving the way for the treatment of disparate retinal diseases. In this review, we provide an update on visual cycle biochemistry and then discuss visual-cycle-related diseases and emerging therapeutics for these disorders. There is hope that these advances will be helpful in treating more complex diseases of the eye, including age-related macular degeneration (AMD).
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Affiliation(s)
- Philip D Kiser
- The Department of Physiology & Biophysics, University of California, Irvine, California, USA; Research Service, The VA Long Beach Health Care System, Long Beach, California, USA; The Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, California, USA.
| | - Krzysztof Palczewski
- The Department of Physiology & Biophysics, University of California, Irvine, California, USA; The Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, California, USA; The Department of Chemistry, University of California, Irvine, California, USA.
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16
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Starace V, Battista M, Brambati M, Pederzolli M, Viganò C, Arrigo A, Cicinelli MV, Bandello F, Parodi MB. Genotypic and phenotypic factors influencing the rate of progression in ABCA-4-related Stargardt disease. EXPERT REVIEW OF OPHTHALMOLOGY 2020. [DOI: 10.1080/17469899.2021.1860753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Vincenzo Starace
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Marco Battista
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Maria Brambati
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Matteo Pederzolli
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Chiara Viganò
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Alessandro Arrigo
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Maria Vittoria Cicinelli
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
- School of Medicine, Vita-Salute San Raffaele University, Milan, Italy
| | - Francesco Bandello
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
- School of Medicine, Vita-Salute San Raffaele University, Milan, Italy
| | - Maurizio Battaglia Parodi
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
- School of Medicine, Vita-Salute San Raffaele University, Milan, Italy
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17
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Yeong JL, Loveman E, Colquitt JL, Royle P, Waugh N, Lois N. Visual cycle modulators versus placebo or observation for the prevention and treatment of geographic atrophy due to age-related macular degeneration. Cochrane Database Syst Rev 2020; 12:CD013154. [PMID: 33331670 PMCID: PMC10726984 DOI: 10.1002/14651858.cd013154.pub2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Age-related macular degeneration (AMD) is a highly prevalent condition in an ever-increasing elderly population. Although insidious in the early stages, advanced AMD (neovascular and atrophic forms) can cause significant visual disability and economic burden on health systems worldwide. The most common form, geographic atrophy, has no effective treatment to date, whereas neovascular AMD can be treated with intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections. Geographic atrophy has a slow disease progression and patients tend to have preserved central vision until the final stages. This tendency, coupled with the use of modern imaging modalities, provides a large window of opportunity to intervene with validated methods to assess treatment efficacy. As geographic atrophy is an increasingly common condition with no effective intervention, many treatments are under investigation, one of which is visual cycle modulators. These medications have been shown to reduce lipofuscin accumulation in pre-clinical studies that have led to several clinical trials, reviewed herein. OBJECTIVES To assess the efficacy and safety of visual cycle modulators for the prevention and treatment of geographic atrophy secondary to AMD. SEARCH METHODS We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2020, Issue 1); MEDLINE Ovid; Embase Ovid; Web of Science Core Collection; Scopus; Association for Research in Vision and Ophthalmology (ARVO) website; ClinicalTrials.gov and the WHO ICTRP to 11 January 2020 with no language restrictions. We also searched using the reference lists of reviews and existing studies and the Cited Reference Search function in Web of Science to identify further relevant studies. SELECTION CRITERIA We included randomised controlled trials (RCTs) and quasi-randomised clinical studies (if available) that compared visual cycle modulators to placebo or no treatment (observation) in people diagnosed with AMD (early, intermediate or geographic atrophy). DATA COLLECTION AND ANALYSIS Two authors independently assessed risk of bias in the included studies and extracted data. Both authors entered data into RevMan 5. We resolved discrepancies through discussion. We graded the certainty of the evidence using the GRADE approach. MAIN RESULTS We included three RCTs from the USA; one of these had clinical sites in Germany. Two studies compared emixustat to placebo while the other compared fenretinide to placebo. All assigned one study eye per participant and, combined, have a total of 821 participants with a majority white ethnicity (97.6%). All participants were diagnosed with geographic atrophy due to AMD based on validated imaging modalities. All three studies have high risk of attrition bias mainly due to ocular adverse effects of emixustat and fenretinide. We considered only one study to be adequately conducted and reported with high risk of bias in only one domain (attrition bias). We considered the other two studies to be poorly reported and to have high risk of attrition bias and reporting bias. People with geographic atrophy treated with emixustat may not experience a clinically important change in best-corrected visual acuity (BCVA) between baseline and 24 months compared to people treated with placebo (mean difference (MD) 1.9 Early Treatment Diabetic Retinopathy Study (ETDRS) letters, 95% confidence interval (CI) -2.34 to 6.14, low-certainty evidence). Emixustat may also result in little or no difference in loss of 15 ETDRS letters or more of BCVA compared with placebo at 24 months (16.4% versus 18%) (risk ratio (RR) 0.91, 95% CI 0.59 to 1.4, low-certainty evidence). In terms of disease progression, emixustat may result in little or no difference in the annual growth rate of geographic atrophy compared with placebo (mean difference MD 0.09 mm2/year (95% CI -0.26 to 0.44, low-certainty evidence). All three studies reported adverse events of both drugs (emixustat: moderate-certainty evidence; fenretinide: low-certainty evidence). The main adverse events were ocular in nature and associated with the mechanism of action of the drugs. Delayed dark adaptation (emixustat: 54.5%; fenretinide: 39.3%) and chromatopsia (emixustat: 22.6%; fenretinide: 25.2%) were the most common adverse events reported, and were the most prevalent reasons for study dropout in emixustat trials. These effects were dose-dependent and resolved after drug cessation. No specific systemic adverse events were considered related to emixustat; only pruritus and rash were considered to be due to fenretinide. One emixustat study reported six deaths, none deemed related to the drug. None of the included RCTs reported the other pre-specified outcomes, including proportion of participants losing 10 letters or more, and mean change in macular sensitivity. We planned to investigate progression to advanced AMD (geographic atrophy or neovascular AMD) in prevention studies, including participants with early or intermediate AMD, but we identified no such studies. Two of the included studies reported an additional outcome - incidence of choroidal neovascularisation (CNV) - that was not in our published protocol. CNV onset may be reduced in those treated with emixustat but the evidence was uncertain (risk ratio (RR) 0.67, 95% CI 0.27 to 1.65, low-certainty evidence), or fenretinide (RR 0.5, 95% CI 0.26 to 0.98, low-certainty evidence) compared to placebo. A dose-dependent relationship was observed with emixustat. AUTHORS' CONCLUSIONS There is limited evidence to support the use of visual cycle modulators (emixustat and fenretinide) for the treatment of established geographic atrophy due to AMD. The possible reduction in the incidence of CNV observed with fenretinide, and to a lesser extent, emixustat, requires formal assessment in focused studies.
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Affiliation(s)
- Jian Lee Yeong
- Belfast and Social Care Trust, Royal Victoria Hospital, Belfast, UK
| | | | | | - Pamela Royle
- Warwick Evidence, Health Sciences Research Institute, Warwick Medical School, University of Warwick, Coventry, UK
| | - Norman Waugh
- Division of Health Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Noemi Lois
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University, Belfast, UK
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18
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Wu J, Gao ZY, Cui DM, Li HH, Zeng JW. All-trans retinoic acid increases ARPE-19 cell apoptosis via activation of reactive oxygen species and endoplasmic reticulum stress pathways. Int J Ophthalmol 2020; 13:1345-1350. [PMID: 32953569 DOI: 10.18240/ijo.2020.09.01] [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: 04/23/2020] [Accepted: 06/02/2020] [Indexed: 02/06/2023] Open
Abstract
AIM To explore the apoptosis of ARPE-19 cells after the treatment with different doses of all-trans-retinoic acid (ATRA). METHODS ARPE-19 cells were used in the in-vitro experiment. Flow cytometry assay was employed to evaluate the level of reactive oxygen species (ROS) and apoptosis. The effects of ATRA (concentrations from 2.5 to 20 µmol/L) on the expression of endoplasmic reticulum stress (ERS) markers in vitro were evaluated by Western blot and real-time quantitative polymerase chain reaction (qRT-PCR) assays. The contribution of ROS and ERS-induced apoptosis in vitro was determined by using N-acetyl-L-cysteine (NAC) and Salubrinal, an antagonist of NAC and ERS, respectively. RESULTS Flow cytometry showed that ATRA significantly increased ARPE-19 cell apoptosis and ROS levels in each group (F=86.39, P<0.001; F=116.839, P<0.001). Western blot and qRT-PCR revealed that levels of CHOP and BIP were elevated in a concentration-dependent pattern after the cells were incubated with ATRA (2.5-20 µmol/L). The upregulation of VEGF-A and CHOP induced by ATRA could be inhibited by NAC (antioxidant) and Salubrinal (ERS inhibitor) in vitro. CONCLUSION ATRA induces the apoptosis of ARPE-19 cells via activated ROS and ERS signaling pathways.
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Affiliation(s)
- Juan Wu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Zhen-Ya Gao
- Xuchang University, School of Medicine, Xuchang 461000, Henan Province, China
| | - Dong-Mei Cui
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Hong-Hui Li
- Chengdu Aier Eye Hospital, Chengdu 610000, Sichuan Province, China
| | - Jun-Wen Zeng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
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19
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Liu X, Meng X, Yang L, Long Y, Fujinami-Yokokawa Y, Ren J, Kurihara T, Tsubota K, Tsunoda K, Fujinami K, Li S. Clinical and genetic characteristics of Stargardt disease in a large Western China cohort: Report 1. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2020; 184:694-707. [PMID: 32845068 DOI: 10.1002/ajmg.c.31838] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 07/31/2020] [Accepted: 08/05/2020] [Indexed: 01/03/2023]
Abstract
Stargardt disease 1 (STGD1) is the most prevalent retinal dystrophy caused by pathogenic biallelic ABCA4 variants. Forty-two unrelated patients mostly originating from Western China were recruited. Comprehensive ophthalmological examinations, including visual acuity measurements (subjective function), fundus autofluorescence (retinal imaging), and full-field electroretinography (objective function), were performed. Next-generation sequencing (target/whole exome) and direct sequencing were conducted. Genotype grouping was performed based on the presence of deleterious variants. The median age of onset/age was 10.0 (5-52)/29.5 (12-72) years, and the median visual acuity in the right/left eye was 1.30 (0.15-2.28)/1.30 (0.15-2.28) in the logarithm of the minimum angle of resolution unit. Ten patients (10/38, 27.0%) showed confined macular dysfunction, and 27 (27/37, 73.7%) had generalized retinal dysfunction. Fifty-eight pathogenic/likely pathogenic ABCA4 variants, including 14 novel variants, were identified. Eight patients (8/35, 22.8%) harbored multiple deleterious variants, and 17 (17/35, 48.6%) had a single deleterious variant. Significant associations were revealed between subjective functional, retinal imaging, and objective functional groups, identifying a significant genotype-phenotype association. This study illustrates a large phenotypic/genotypic spectrum in a large well-characterized STGD1 cohort. A distinct genetic background of the Chinese population from the Caucasian population was identified; meanwhile, a genotype-phenotype association was similarly represented.
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Affiliation(s)
- Xiao Liu
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Xiaohong Meng
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Lizhu Yang
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Yanling Long
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Yu Fujinami-Yokokawa
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Health Policy and Management, Keio University School of Medicine, Tokyo, Japan.,Department of Public Health Research, Yokokawa Clinic, Osaka, Japan
| | - Jiayun Ren
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Toshihide Kurihara
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Kazuo Tsubota
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Kazushige Tsunoda
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Kaoru Fujinami
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.,UCL Institute of Ophthalmology, London, UK.,Moorfields Eye Hospital, London, UK
| | - Shiying Li
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China
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20
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Taveau N, Cubizolle A, Guillou L, Pinquier N, Moine E, Cia D, Kalatzis V, Vercauteren J, Durand T, Crauste C, Brabet P. Preclinical pharmacology of a lipophenol in a mouse model of light-induced retinopathy. Exp Mol Med 2020; 52:1090-1101. [PMID: 32641711 PMCID: PMC8080701 DOI: 10.1038/s12276-020-0460-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/18/2020] [Accepted: 04/21/2020] [Indexed: 12/17/2022] Open
Abstract
Environmental light has deleterious effects on the outer retina in human retinopathies, such as ABCA4-related Stargardt’s disease and dry age-related macular degeneration. These effects involve carbonyl and oxidative stress, which contribute to retinal cell death and vision loss. Here, we used an albino Abca4−/− mouse model, the outer retina of which shows susceptibility to acute photodamage, to test the protective efficacy of a new polyunsaturated fatty acid lipophenol derivative. Anatomical and functional analyses demonstrated that a single intravenous injection of isopropyl-phloroglucinol-DHA, termed IP-DHA, dose-dependently decreased light-induced photoreceptor degeneration and preserved visual sensitivity. This protective effect persisted for 3 months. IP-DHA did not affect the kinetics of the visual cycle in vivo or the activity of the RPE65 isomerase in vitro. Moreover, IP-DHA administered by oral gavage showed significant protection of photoreceptors against acute light damage. In conclusion, short-term tests in Abca4-deficient mice, following single-dose administration and light exposure, identify IP-DHA as a therapeutic agent for the prevention of retinal degeneration. Treating retinal damage in both aging and young patients might now be easier, thanks to treatment with a lipophenol, an omega-3 fatty acid linked to an antioxidant. The retina is the part of the eye that senses light, aided by light-sensitive pigments. However, these light-sensitive pigments can be converted by light to toxic byproducts, and in some individuals, these toxic byproducts can accumulate, damaging the retina and leading to vision loss. Philippe Brabet at the Montpellier Institute of Neuroscience in France and co-workers found that lipophenol treatment protected retinal cells from damage in a mouse model of retinal disease, and that a single dose has been effective in preserving vision. These results may help in finding new treatments for retinal diseases such as Stargardt disease and age-related macular degeneration.
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Affiliation(s)
- Nicolas Taveau
- Institut des Neurosciences de Montpellier, INSERM U1051, F-34091, Montpellier, France.,Université de Montpellier, F-34091, Montpellier, France
| | - Aurélie Cubizolle
- Institut des Neurosciences de Montpellier, INSERM U1051, F-34091, Montpellier, France.,Université de Montpellier, F-34091, Montpellier, France
| | - Laurent Guillou
- Institut des Neurosciences de Montpellier, INSERM U1051, F-34091, Montpellier, France.,Université de Montpellier, F-34091, Montpellier, France
| | - Nicolas Pinquier
- Institut des Neurosciences de Montpellier, INSERM U1051, F-34091, Montpellier, France
| | - Espérance Moine
- Institut des Biomolecules Max Mousseron (IBMM), UMR 5247 - Université de Montpellier, CNRS, ENSCM, F-34095, Montpellier, France
| | - David Cia
- Laboratoire de Biophysique Neurosensorielle, UMR INSERM 1107, Facultés de Médecine et de Pharmacie, F-63001, Clermont-Ferrand, France
| | - Vasiliki Kalatzis
- Institut des Neurosciences de Montpellier, INSERM U1051, F-34091, Montpellier, France.,Université de Montpellier, F-34091, Montpellier, France
| | - Joseph Vercauteren
- Institut des Biomolecules Max Mousseron (IBMM), UMR 5247 - Université de Montpellier, CNRS, ENSCM, F-34095, Montpellier, France
| | - Thierry Durand
- Institut des Biomolecules Max Mousseron (IBMM), UMR 5247 - Université de Montpellier, CNRS, ENSCM, F-34095, Montpellier, France
| | - Céline Crauste
- Institut des Biomolecules Max Mousseron (IBMM), UMR 5247 - Université de Montpellier, CNRS, ENSCM, F-34095, Montpellier, France
| | - Philippe Brabet
- Institut des Neurosciences de Montpellier, INSERM U1051, F-34091, Montpellier, France. .,Université de Montpellier, F-34091, Montpellier, France.
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21
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Cheng KJ, Hsieh CM, Nepali K, Liou JP. Ocular Disease Therapeutics: Design and Delivery of Drugs for Diseases of the Eye. J Med Chem 2020; 63:10533-10593. [PMID: 32482069 DOI: 10.1021/acs.jmedchem.9b01033] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The ocular drug discovery field has evidenced significant advancement in the past decade. The FDA approvals of Rhopressa, Vyzulta, and Roclatan for glaucoma, Brolucizumab for wet age-related macular degeneration (wet AMD), Luxturna for retinitis pigmentosa, Dextenza (0.4 mg dexamethasone intracanalicular insert) for ocular inflammation, ReSure sealant to seal corneal incisions, and Lifitegrast for dry eye represent some of the major developments in the field of ocular therapeutics. A literature survey also indicates that gene therapy, stem cell therapy, and target discovery through genomic research represent significant promise as potential strategies to achieve tissue repair or regeneration and to attain therapeutic benefits in ocular diseases. Overall, the emergence of new technologies coupled with first-in-class entries in ophthalmology are highly anticipated to restructure and boost the future trends in the field of ophthalmic drug discovery. This perspective focuses on various aspects of ocular drug discovery and the recent advances therein. Recent medicinal chemistry campaigns along with a brief overview of the structure-activity relationships of the diverse chemical classes and developments in ocular drug delivery (ODD) are presented.
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Affiliation(s)
- Kuei-Ju Cheng
- School of Pharmacy, College of Pharmacy, Taipei Medical University, 250 Wuxing Street, Taipei 11031, Taiwan.,Department of Pharmacy, Taipei Municipal Wanfang Hospital, Taipei Medical University, No. 111, Section 3, Xing-Long Road, Taipei 11696, Taiwan
| | - Chien-Ming Hsieh
- School of Pharmacy, College of Pharmacy, Taipei Medical University, 250 Wuxing Street, Taipei 11031, Taiwan
| | - Kunal Nepali
- School of Pharmacy, College of Pharmacy, Taipei Medical University, 250 Wuxing Street, Taipei 11031, Taiwan
| | - Jing-Ping Liou
- School of Pharmacy, College of Pharmacy, Taipei Medical University, 250 Wuxing Street, Taipei 11031, Taiwan
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22
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Ciulla TA, Hussain RM, Berrocal AM, Nagiel A. Voretigene neparvovec-rzyl for treatment of RPE65-mediated inherited retinal diseases: a model for ocular gene therapy development. Expert Opin Biol Ther 2020; 20:565-578. [DOI: 10.1080/14712598.2020.1740676] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Thomas A. Ciulla
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, IN, USA
- Retina Service, Midwest Eye Institute, Indianapolis, IN, USA
| | | | - Audina M. Berrocal
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Aaron Nagiel
- Department of Surgery, the Vision Center, Children’s Hospital Los Angeles, Los Angeles, CA, USA
- The Saban Research Institute, Children’s Hospital Los Angeles, Los Angeles, CA, USA
- USC Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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Ortega JT, Parmar T, Jastrzebska B. Flavonoids enhance rod opsin stability, folding, and self-association by directly binding to ligand-free opsin and modulating its conformation. J Biol Chem 2019; 294:8101-8122. [PMID: 30944172 DOI: 10.1074/jbc.ra119.007808] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 03/27/2019] [Indexed: 12/29/2022] Open
Abstract
Rhodopsin (Rho) is a visual G protein-coupled receptor expressed in the rod photoreceptors of the eye, where it mediates transmission of a light signal into a cell and converts this signal into a nerve impulse. More than 100 mutations in Rho are linked to various ocular impairments, including retinitis pigmentosa (RP). Accordingly, much effort has been directed toward developing ligands that target Rho and improve its folding and stability. Natural compounds may provide another viable approach to such drug discovery efforts. The dietary polyphenol compounds, ubiquitously present in fruits and vegetables, have beneficial effects in several eye diseases. However, the underlying mechanism of their activity is not fully understood. In this study, we used a combination of computational methods, biochemical and biophysical approaches, including bioluminescence resonance energy transfer, and mammalian cell expression systems to clarify the effects of four common bioactive flavonoids (quercetin, myricetin, and their mono-glycosylated forms quercetin-3-rhamnoside and myricetrin) on rod opsin stability, function, and membrane organization. We observed that by directly interacting with ligand-free opsin, flavonoids modulate its conformation, thereby causing faster entry of the retinal chromophore into its binding pocket. Moreover, flavonoids significantly increased opsin stability, most likely by introducing structural rigidity and promoting receptor self-association within the biological membranes. Of note, the binding of flavonoids to an RP-linked P23H opsin variant partially restored its normal cellular trafficking. Together, our results suggest that flavonoids could be utilized as lead compounds in the development of effective nonretinoid therapeutics for managing RP-related retinopathies.
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Affiliation(s)
- Joseph T Ortega
- Department of Pharmacology, Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106
| | - Tanu Parmar
- Department of Pharmacology, Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106
| | - Beata Jastrzebska
- Department of Pharmacology, Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106.
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Glen WB, Peterseim MMW, Badilla R, Znoyko I, Bourg A, Wilson R, Hardiman G, Wolff D, Martinez J. A high prevalence of biallelic RPE65 mutations in Costa Rican children with Leber congenital amaurosis and early-onset retinal dystrophy. Ophthalmic Genet 2019; 40:110-117. [PMID: 30870047 DOI: 10.1080/13816810.2019.1582069] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Leber congenital amaurosis (LCA) and early-onset retinal dystrophy (EORD), are primary causes of inherited childhood blindness. Both are autosomal recessive diseases, with mutations in more than 25 genes explaining approximately ~70% of cases. However, the genetic cause for many cases remains unclear. Sequencing studies from genetically isolated populations with increased prevalence of a disorder has proven useful for rare variant studies, making Costa Rica an ideal place to study LCA/EORD genetics. MATERIALS AND METHODS Twenty-eight affected children (25 LCA, three EORD) and their immediate family members, totaling 52 individuals (30 affected) from 22 families, were sequenced. Whole exome sequencing was performed on all affected individuals. Available parents were analyzed either by whole exome sequencing (WES) or Sanger sequencing to determine transmission. RESULTS All affected individuals demonstrated compound heterozygous or homozygous mutations in known Inherited Retinal Disease (IRD) associated genes. Twelve variants were identified in at least one individual in three genes, RDH12, RPE65, and USH2A. Four recurrent RPE65 mutations were observed in 97% of individuals and 95% of families. All patients with LCA and two of the three individuals with EORD had biallelic mutations in RPE65; one child with EORD had a homozygous RDH12 mutation. CONCLUSIONS These data suggest that the majority of LCA/EORD in Costa Rica is due to four founder mutations in RPE65 which have been maintained in this genetically isolated population. This finding is of great clinical significance due to the availability of gene therapy recently approved in the US and European Union for patients with biallelic RPE65 defects.
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Affiliation(s)
- W Bailey Glen
- a Pathology and Laboratory Medicine , Medical University of South Carolina.,b Center for Genomic Medicine , Medical University of South Carolina
| | | | - Ramses Badilla
- d Genetics and Metabolism , National Children's Hospital , San José , Costa Rica.,e Caja Costarricense del Seguro Social
| | - Iya Znoyko
- a Pathology and Laboratory Medicine , Medical University of South Carolina
| | - Andre Bourg
- f Department of Medicine , Medical University of South Carolina
| | - Robert Wilson
- a Pathology and Laboratory Medicine , Medical University of South Carolina.,b Center for Genomic Medicine , Medical University of South Carolina
| | - Gary Hardiman
- b Center for Genomic Medicine , Medical University of South Carolina.,f Department of Medicine , Medical University of South Carolina.,g Institute for Global Food Security , Queen's University Belfast
| | - Daynna Wolff
- a Pathology and Laboratory Medicine , Medical University of South Carolina
| | - Joaquin Martinez
- e Caja Costarricense del Seguro Social.,h Division of Ophthalmology , National Children's Hospital , San José , Costa Rica
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Sundaramurthi H, Moran A, Perpetuini AC, Reynolds A, Kennedy B. Emerging Drug Therapies for Inherited Retinal Dystrophies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1185:263-267. [PMID: 31884622 DOI: 10.1007/978-3-030-27378-1_43] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Worldwide, 1 in 2000 people suffer from inherited retinal dystrophies (IRD). Individuals with IRD typically present with progressive vision loss that ultimately results in blindness. Unfortunately, effective treatment options are not widely available due to the genetic and clinical heterogeneity of these diseases. There are multiple gene, cell, and drug-based therapies in various phases of clinical trials for IRD. This mini-review documents current progress made in drug-based clinical trials for treating IRD.
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Affiliation(s)
- Husvinee Sundaramurthi
- UCD Conway Institute, University College Dublin,, Dublin, Ireland.
- UCD School of Biomolecular and Biomedical Sciences, University College Dublin, Dublin, Ireland.
- UCD School of Medicine, University College Dublin, Dublin, Ireland.
- Systems Biology Ireland, University College Dublin, Dublin, Ireland.
- UCD School of Veterinary Medicine, University College Dublin, Dublin, Ireland.
| | - Ailís Moran
- UCD Conway Institute, University College Dublin,, Dublin, Ireland
- UCD School of Biomolecular and Biomedical Sciences, University College Dublin, Dublin, Ireland
| | - Andrea Cerquone Perpetuini
- UCD Conway Institute, University College Dublin,, Dublin, Ireland
- UCD School of Biomolecular and Biomedical Sciences, University College Dublin, Dublin, Ireland
| | - Alison Reynolds
- UCD Conway Institute, University College Dublin,, Dublin, Ireland
- UCD School of Veterinary Medicine, University College Dublin, Dublin, Ireland
| | - Breandán Kennedy
- UCD Conway Institute, University College Dublin,, Dublin, Ireland
- UCD School of Biomolecular and Biomedical Sciences, University College Dublin, Dublin, Ireland
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Cicinelli MV, Battista M, Starace V, Battaglia Parodi M, Bandello F. Monitoring and Management of the Patient with Stargardt Disease. CLINICAL OPTOMETRY 2019; 11:151-165. [PMID: 31819694 PMCID: PMC6886536 DOI: 10.2147/opto.s226595] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 11/16/2019] [Indexed: 05/10/2023]
Abstract
Stargardt disease (STGD1) represents one of the major common causes of inherited irreversible visual loss. Due to its high phenotypic and genotypic heterogeneity, STGD1 is a complex disease to understand. Non-invasive imaging, biochemical, and genetic advances have led to substantial improvements in unveiling the disease processes and novel promising therapeutic landscapes have been proposed. This review recapitulates the modalities for monitoring patients with STGD1 and the therapeutic options currently under investigation for the different stages of the disease.
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Affiliation(s)
- Maria Vittoria Cicinelli
- Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan, Italy
- Correspondence: Maria Vittoria Cicinelli Department of Ophthalmology, San Raffaele Vita-Salute University, Via Olgettina, 60, Milano20132, ItalyTel +39 02 26432648Fax +39 02 26483643 Email
| | - Marco Battista
- Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Vincenzo Starace
- Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan, Italy
| | | | - Francesco Bandello
- Department of Ophthalmology, University Vita-Salute, IRCCS Ospedale San Raffaele, Milan, Italy
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Kang MK, Lee EJ, Kim YH, Kim DY, Oh H, Kim SI, Kang YH. Chrysin Ameliorates Malfunction of Retinoid Visual Cycle through Blocking Activation of AGE-RAGE-ER Stress in Glucose-Stimulated Retinal Pigment Epithelial Cells and Diabetic Eyes. Nutrients 2018; 10:nu10081046. [PMID: 30096827 PMCID: PMC6116048 DOI: 10.3390/nu10081046] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 08/05/2018] [Accepted: 08/06/2018] [Indexed: 12/20/2022] Open
Abstract
Diabetes-associated visual cycle impairment has been implicated in diabetic retinopathy, and chronic hyperglycemia causes detrimental effects on visual function. Chrysin, a naturally occurring flavonoid found in various herbs, has anti-inflammatory, antioxidant, and neuroprotective properties. The goal of the current study was to identify the retinoprotective role of chrysin in maintaining robust retinoid visual cycle-related components. The in vitro study employed human retinal pigment epithelial (RPE) cells exposed to 33 mM of glucose or advanced glycation end products (AGEs) in the presence of 1–20 μM chrysin for three days. In the in vivo study, 10 mg/kg of chrysin was orally administrated to db/db mice. Treating chrysin reversed the glucose-induced production of vascular endothelial growth factor, insulin-like growth factor-1, and pigment epithelium-derived factor (PEDF) in RPE cells. The outer nuclear layer thickness of chrysin-exposed retina was enhanced. The oral gavage of chrysin augmented the levels of the visual cycle enzymes of RPE65, lecithin retinol acyltransferase (LRAT), retinol dehydrogenase 5 (RDH5), and rhodopsin diminished in db/db mouse retina. The diabetic tissue levels of the retinoid binding proteins and the receptor of the cellular retinol-binding protein, cellular retinaldehyde-binding protein-1, interphotoreceptor retinoid-binding protein and stimulated by retinoic acid 6 were restored to those of normal mouse retina. The presence of chrysin demoted AGE secretion and AGE receptor (RAGE) induction in glucose-exposed RPE cells and diabetic eyes. Chrysin inhibited the reduction of PEDF, RPE 65, LRAT, and RDH5 in 100 μg/mL of AGE-bovine serum albumin-exposed RPE cells. The treatment of RPE cells with chrysin reduced the activation of endoplasmic reticulum (ER) stress. Chrysin inhibited the impairment of the retinoid visual cycle through blocking ER stress via the AGE-RAGE activation in glucose-stimulated RPE cells and diabetic eyes. This is the first study demonstrating the protective effects of chrysin on the diabetes-associated malfunctioned visual cycle.
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Affiliation(s)
- Min-Kyung Kang
- Department of Food Science and Nutrition, Hallym University, Chuncheon 24252, Korea.
| | - Eun-Jung Lee
- Department of Food Science and Nutrition, Hallym University, Chuncheon 24252, Korea.
| | - Yun-Ho Kim
- Department of Food Science and Nutrition, Hallym University, Chuncheon 24252, Korea.
| | - Dong Yeon Kim
- Department of Food Science and Nutrition, Hallym University, Chuncheon 24252, Korea.
| | - Hyeongjoo Oh
- Department of Food Science and Nutrition, Hallym University, Chuncheon 24252, Korea.
| | - Soo-Il Kim
- Department of Food Science and Nutrition, Hallym University, Chuncheon 24252, Korea.
| | - Young-Hee Kang
- Department of Food Science and Nutrition, Hallym University, Chuncheon 24252, Korea.
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