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Kwon YS, Han Z. Advanced nanomedicines for the treatment of age-related macular degeneration. NANOSCALE 2024; 16:16769-16790. [PMID: 39177654 DOI: 10.1039/d4nr01917b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2024]
Abstract
The critical and unmet medical need for novel therapeutic advancements in the treatment of age-related macular degeneration (AMD) cannot be overstated, particularly given the aging global population and the increasing prevalence of this condition. Current AMD therapy involves intravitreal treatments that require monthly or bimonthly injections to maintain optimal efficacy. This underscores the necessity for improved approaches, prompting recent research into developing advanced drug delivery systems to prolong the intervals between treatments. Nanoparticle-based therapeutic approaches have enabled the controlled release of drugs, targeted delivery of therapeutic materials, and development of smart solutions for the harsh microenvironment of diseased tissues, offering a new perspective on ocular disease treatment. This review emphasizes the latest pre-clinical treatment options in ocular drug delivery to the retina and explores the advantages of nanoparticle-based therapeutic approaches, with a focus on AMD, the leading cause of irreversible blindness in the elderly.
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Affiliation(s)
- Yong-Su Kwon
- Department of Ophthalmology, School of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
| | - Zongchao Han
- Department of Ophthalmology, School of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
- Division of Pharmacoengineering & Molecular Pharmaceutics, Eshelman School of Pharmacy, the University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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Minibayeva FV, Rassabina AE, Zakirjanova GF, Fedorov NS, Khabibrakhmanova VR, Galeeva EI, Kuznetsova EA, Malomouzh AI, Petrov AM. Protective properties of melanin from lichen Lobaria pulmonaria (L.) HOFFM. In models of oxidative stress in skeletal muscle. Fitoterapia 2024; 177:106127. [PMID: 39019238 DOI: 10.1016/j.fitote.2024.106127] [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: 01/29/2024] [Revised: 06/16/2024] [Accepted: 07/13/2024] [Indexed: 07/19/2024]
Abstract
Melanin is a dark pigment from the group of phenolic or indole polymers with inherent biocompatibility and antioxidant capacity. In extremophilic lichen Lobaria pulmonaria, melanin is responsible for protective properties against hostile environments. Herein, the ability of melanin extracted from L. pulmonaria to counteract oxidative stress and related damages was studied in the mouse diaphragm, the main respiratory muscle. Initial in vitro experiments demonstrated ultraviolet (UV)-absorbing, antioxidant and metal chelating activities of melanin. This melanin can form nanoparticles and stabile colloidal system at concentration of 5 μg/ml. Pretreatment of the muscle with melanin (5 μg/ml) markedly reduced UV-induced increase in intracellular and extracellular reactive oxygen species (ROS) as well as antimycin A-mediated enhancement in mitochondrial ROS production accompanied by lipid peroxidation and membrane asymmetry loss. In addition, melanin attenuated suppression of neuromuscular transmission and alterations of contractile responses provoked by hydrogen peroxide. Thus, this study shed the light on the perspectives of the application of a lichen melanin as a protective component for treatment of skeletal muscle disorders, which are accompanied with an increased ROS production.
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Affiliation(s)
- Farida V Minibayeva
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, Box 30, Kazan 420111, Russia.
| | - Anna E Rassabina
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, Box 30, Kazan 420111, Russia
| | - Guzalia F Zakirjanova
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, Box 30, Kazan 420111, Russia
| | - Nikita S Fedorov
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, Box 30, Kazan 420111, Russia
| | - Venera R Khabibrakhmanova
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, Box 30, Kazan 420111, Russia
| | - Ekaterina I Galeeva
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, Box 30, Kazan 420111, Russia
| | - Eva A Kuznetsova
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, Box 30, Kazan 420111, Russia
| | - Artem I Malomouzh
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, Box 30, Kazan 420111, Russia; Kazan National Research Technical University, 10, K. Marx St., Kazan 420111, Russia
| | - Alexey M Petrov
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, Box 30, Kazan 420111, Russia; Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 420008 Kazan, Russia; Kazan State Mediсal University, 49 Butlerova Street, Kazan 420012, Russia.
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Kaufmann M, Han Z. RPE melanin and its influence on the progression of AMD. Ageing Res Rev 2024; 99:102358. [PMID: 38830546 PMCID: PMC11260545 DOI: 10.1016/j.arr.2024.102358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 05/27/2024] [Indexed: 06/05/2024]
Abstract
OBJECTIVE The aim of this review article is to summarize the latest findings and current understanding of the origin of melanin in the retinal pigment epithelium (RPE), its function within the RPE, its role in the pathogenesis of age-related macular degeneration (AMD), its effect on retinal development, and its potential therapeutic benefit in the treatment of AMD. METHODS A comprehensive search of peer-reviewed journals was conducted using various combinations of key terms such as "melanin," "retinal pigment epithelium" or "RPE," "age-related macular degeneration" or AMD," "lipofuscin," "oxidative stress," and "albinism." Databases searched include PubMed, Scopus, Science Direct, and Google Scholar. 147 papers published between the years of 1957 and 2023 were considered with an emphasis on recent findings. SUMMARY OF FINDINGS AMD is thought to result from chronic oxidative stress within the RPE that results in cellular dysfunction, metabolic dysregulation, inflammation, and lipofuscin accumulation. Melanin functions as a photoscreener, free radical scavenger, and metal cation binding reservoir within the RPE. RPE melanin does not regenerate, and it undergoes degradation over time in response to chronic light exposure and oxidative stress. RPE melanin is important for retinal development and RPE function, and in the aging eye, melanin loss is associated with increased lipid peroxidation, inflammation, and the accumulation of toxic oxidized cellular products. Therefore, melanin-based treatments may serve to preserve RPE and retinal function in AMD. CONCLUSIONS The pathogenesis of AMD is not fully understood, but RPE dysfunction and melanin loss in response to chronic oxidative stress and inflammation are thought to be primary drivers of the disease. Due to melanin's antioxidative effects, melanin-based nanotechnology represents a promising avenue for the treatment of AMD.
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Affiliation(s)
- Mary Kaufmann
- University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Zongchao Han
- Department of Ophthalmology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Division of Pharmacoengineering & Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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Kwon Y, Munsoor J, Kaufmann M, Zheng M, Smirnov AI, Han Z. Polydopamine Nanoparticles as Mimicking RPE Melanin for the Protection of Retinal Cells Against Blue Light-Induced Phototoxicity. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2400230. [PMID: 38816934 PMCID: PMC11304300 DOI: 10.1002/advs.202400230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 05/15/2024] [Indexed: 06/01/2024]
Abstract
Exposure of the eyes to blue light can induce the overproduction of reactive oxygen species (ROS) in the retina and retinal pigment epithelium (RPE) cells, potentially leading to pathological damage of age-related macular degeneration (AMD). While the melanin in RPE cells absorbs blue light and prevents ROS accumulation, the loss and dysfunction of RPE melanin due to age-related changes may contribute to photooxidation toxicity. Herein, a novel approach utilizing a polydopamine-replenishing strategy via a single-dose intravitreal (IVT) injection is presented to protect retinal cells against blue light-induced phototoxicity. To investigate the effects of overexposure to blue light on retinal cells, a blue light exposure Nrf2-deficient mouse model is created, which is susceptible to light-induced retinal lesions. After blue light irradiation, retina degeneration and an overproduction of ROS are observed. The polydopamine-replenishing strategy demonstrated effectiveness in maintaining retinal structural integrity and preventing retina degeneration by reducing ROS production in retinal cells and limiting the phototoxicity of blue light exposure. These findings highlight the potential of polydopamine as a simple and effective replenishment for providing photoprotection against high-energy blue light exposure.
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Affiliation(s)
- Yong‐Su Kwon
- Department of OphthalmologyThe University of North Carolina at Chapel HillChapel HillNC27599USA
| | - Julie Munsoor
- Department of OphthalmologyThe University of North Carolina at Chapel HillChapel HillNC27599USA
| | - Mary Kaufmann
- Department of OphthalmologyThe University of North Carolina at Chapel HillChapel HillNC27599USA
| | - Min Zheng
- Department of OphthalmologyThe University of North Carolina at Chapel HillChapel HillNC27599USA
| | - Alex I. Smirnov
- Department of ChemistryNorth Carolina State UniversityRaleighNC27695USA
| | - Zongchao Han
- Department of OphthalmologyThe University of North Carolina at Chapel HillChapel HillNC27599USA
- Division of Pharmacoengineering & Molecular PharmaceuticsEshelman School of PharmacyThe University of North Carolina at Chapel HillChapel HillNC27599USA
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Dontsov A, Ostrovsky M. Retinal Pigment Epithelium Pigment Granules: Norms, Age Relations and Pathology. Int J Mol Sci 2024; 25:3609. [PMID: 38612421 PMCID: PMC11011557 DOI: 10.3390/ijms25073609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024] Open
Abstract
The retinal pigment epithelium (RPE), which ensures the normal functioning of the neural retina, is a pigmented single-cell layer that separates the retina from the Bruch's membrane and the choroid. There are three main types of pigment granules in the RPE cells of the human eye: lipofuscin granules (LG) containing the fluorescent "age pigment" lipofuscin, melanoprotein granules (melanosomes, melanolysosomes) containing the screening pigment melanin and complex melanolipofuscin granules (MLG) containing both types of pigments simultaneously-melanin and lipofuscin. This review examines the functional role of pigment granules in the aging process and in the development of oxidative stress and associated pathologies in RPE cells. The focus is on the process of light-induced oxidative degradation of pigment granules caused by reactive oxygen species. The reasons leading to increased oxidative stress in RPE cells as a result of the oxidative degradation of pigment granules are considered. A mechanism is proposed to explain the phenomenon of age-related decline in melanin content in RPE cells. The essence of the mechanism is that when the lipofuscin part of the melanolipofuscin granule is exposed to light, reactive oxygen species are formed, which destroy the melanin part. As more melanolipofuscin granules are formed with age and the development of degenerative diseases, the melanin in pigmented epithelial cells ultimately disappears.
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Affiliation(s)
| | - Mikhail Ostrovsky
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow 119334, Russia;
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Meyer BI, Liao A, Sanda GE, Craven C, Wells JR, Hendrick AM, Yan J, Jain N. Fundus imaging features of congenital rubella retinopathy. Graefes Arch Clin Exp Ophthalmol 2024; 262:777-788. [PMID: 37878037 DOI: 10.1007/s00417-023-06284-x] [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: 07/18/2023] [Revised: 10/06/2023] [Accepted: 10/12/2023] [Indexed: 10/26/2023] Open
Abstract
PURPOSE To evaluate the clinical characteristics of congenital rubella retinopathy (CRR) with modern fundus imaging. METHODS Single-center case series. Eleven patients (2005-2020) at the Emory Eye Center with known or presumed CRR. Trained image readers reviewed fundus imaging (color fundus photography, widefield pseudocolor imaging, near-infrared reflectance imaging, autofluorescence imaging, and spectral-domain optical coherence tomography) for pre-specified features suggestive of CRR. RESULTS Eleven patients with confirmed (63.6%) or presumed (36.3%) CRR were identified. All were female with median (range) age of 53 (35-67) years. Six (54.5%) were born during the 1964-1965 United States rubella epidemic. All had congenital hearing loss. Two (18.2%) had a congenital heart defect. Eleven (50.0%) eyes had salt-and-pepper retinal pigmentary changes. Twenty-two eyes (100.0%) had irregularly distributed regions of speckled hypoautofluorescence. One eye (4.5%) had a presumed macular neovascularization. CONCLUSION Modern fundus imaging demonstrates characteristic features of CRR, even when pigmentary changes are not readily apparent on examination. Widefield autofluorescence findings of irregularly distributed speckled hypoautofluorescence are particularly revealing. This series of newly diagnosed adults with CRR may represent the milder end of the phenotypic spectrum of this condition, highlighting imaging findings that may aid in diagnostically challenging cases of CRR.
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Affiliation(s)
- Benjamin I Meyer
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Albert Liao
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Road, NE, Suite 2400, Atlanta, GA, 30322, USA
| | - Gregory E Sanda
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Road, NE, Suite 2400, Atlanta, GA, 30322, USA
| | - Caroline Craven
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Road, NE, Suite 2400, Atlanta, GA, 30322, USA
| | - Jill R Wells
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Road, NE, Suite 2400, Atlanta, GA, 30322, USA
| | - Andrew M Hendrick
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Road, NE, Suite 2400, Atlanta, GA, 30322, USA
| | - Jiong Yan
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Road, NE, Suite 2400, Atlanta, GA, 30322, USA
| | - Nieraj Jain
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Road, NE, Suite 2400, Atlanta, GA, 30322, USA.
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7
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Tan Y, Li Y, Ren L, Fu H, Li Q, Liu S. Integrative proteome and metabolome analyses reveal molecular basis underlying growth and nutrient composition in the Pacific oyster, Crassostrea gigas. J Proteomics 2024; 290:105021. [PMID: 37838097 DOI: 10.1016/j.jprot.2023.105021] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 09/28/2023] [Accepted: 10/03/2023] [Indexed: 10/16/2023]
Abstract
In order to comprehend the molecular basis of growth, nutrient composition, and color pigmentation in oysters, comparative proteome and metabolome analyses of two selectively bred oyster strains with contrasting growth rate and shell color were used in this study. A total of 289 proteins and 224 metabolites were identified differentially expressed between the two strains. We identified a series of specifically enriched functional clusters implicated in protein biosynthesis (RPL4, MRPS7, and CARS), fatty acid metabolism (ACSL5, PEX3, ACOXI, CPTIA, FABP6, and HSD17B12), energy metabolism (FH, PPP1R7, CLAM2, and RGN), cell proliferation (MYB, NFYC, DOHH, TOP2a, SMARCA5, and SMARCC2), material transport (ABCB1, ABCB8, VPS16, and VPS33a), and pigmentation (RDH7, RDH13, Retsat, COX15, and Cyp3a9). Integrated proteome and metabolome analyses indicate that fast-growing strain utilize energy-efficient mechanisms of ATP generation while promoting protein and polyunsaturated fatty acid synthesis, activating the cell cycle to increase cell proliferation and thus promoting their biomass increase. These results uncovered molecular mechanisms underlying growth regulation, nutrition quality, and pigmentation and provided candidate biomarkers for molecular breeding in oysters. SIGNIFICANCE: Rapid growth has always been the primary breeding objective to increase the production profits of Pacific oyster (Crassostrea gigas), while favorable nutritional quality and beautiful color add commercial value. In recent years, proteomic and metabolomic techniques have been widely used in marine organisms, although these techniques are seldom utilized to study oyster growth and development. In this study, two C. gigas strains with contrasted phenotypes in growth and shell color provided an ideal model for unraveling the molecular basis of growth and nutrient composition through a comparison of the proteome and metabolome. Since proteins and metabolites are the critical undertakers and the end products of cellular regulatory processes, identifying the differentially expressed proteins and metabolites would allow for discovering biomarkers and pathways that were implicated in cell growth, proliferation, and other critical functions. This work provides valuable resources in assistance with molecular breeding of oyster strains with superior production traits of fast-growth and high-quality nutrient value.
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Affiliation(s)
- Ying Tan
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, and College of Fisheries, Ocean University of China, Qingdao 266003, China
| | - Yongjing Li
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, and College of Fisheries, Ocean University of China, Qingdao 266003, China
| | - Liting Ren
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, and College of Fisheries, Ocean University of China, Qingdao 266003, China
| | - Huiru Fu
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, and College of Fisheries, Ocean University of China, Qingdao 266003, China
| | - Qi Li
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, and College of Fisheries, Ocean University of China, Qingdao 266003, China
| | - Shikai Liu
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, and College of Fisheries, Ocean University of China, Qingdao 266003, China.
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Sanchez-Bretano A, Keeling E, Scott JA, Lynn SA, Soundara-Pandi SP, Macdonald SL, Newall T, Griffiths H, Lotery AJ, Ratnayaka JA, Self JE, Lee H. Human equivalent doses of L-DOPA rescues retinal morphology and visual function in a murine model of albinism. Sci Rep 2023; 13:17173. [PMID: 37821525 PMCID: PMC10567794 DOI: 10.1038/s41598-023-44373-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 10/07/2023] [Indexed: 10/13/2023] Open
Abstract
L-DOPA is deficient in the developing albino eye, resulting in abnormalities of retinal development and visual impairment. Ongoing retinal development after birth has also been demonstrated in the developing albino eye offering a potential therapeutic window in humans. To study whether human equivalent doses of L-DOPA/Carbidopa administered during the crucial postnatal period of neuroplasticity can rescue visual function, OCA C57BL/6 J-c2J OCA1 mice were treated with a 28-day course of oral L-DOPA/Carbidopa at 3 different doses from 15 to 43 days postnatal age (PNA) and for 3 different lengths of treatment, to identify optimum dosage and treatment length. Visual electrophysiology, acuity, and retinal morphology were measured at 4, 5, 6, 12 and 16 weeks PNA and compared to untreated C57BL/6 J (WT) and OCA1 mice. Quantification of PEDF, βIII-tubulin and syntaxin-3 expression was also performed. Our data showed impaired retinal morphology, decreased retinal function and lower visual acuity in untreated OCA1 mice compared to WT mice. These changes were diminished or eliminated when treated with higher doses of L-DOPA/Carbidopa. Our results demonstrate that oral L-DOPA/Carbidopa supplementation at human equivalent doses during the postnatal critical period of retinal neuroplasticity can rescue visual retinal morphology and retinal function, via PEDF upregulation and modulation of retinal synaptogenesis, providing a further step towards developing an effective treatment for albinism patients.
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Affiliation(s)
- Aida Sanchez-Bretano
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
| | - Eloise Keeling
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
| | - Jennifer A Scott
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
| | - Savannah A Lynn
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
| | - Sudha Priya Soundara-Pandi
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
| | - Sarah L Macdonald
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
| | - Tutte Newall
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
| | - Helen Griffiths
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
| | - Andrew J Lotery
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
- Eye Unit, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK
| | - J Arjuna Ratnayaka
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
| | - Jay E Self
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK
- Eye Unit, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK
| | - Helena Lee
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Sir Henry Wellcome Laboratories, Southampton University Hospital, South Block Mail Point 806, Level D, Southampton, SO16 6YD, UK.
- Eye Unit, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, SO16 6YD, UK.
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Yan L, Jin Z, Lin R, Lu X, Shan X, Zhu S, Fang Z, Cui X, Tian P. InGaN micro-LED array with integrated emission and detection functions for color detection application. OPTICS LETTERS 2023; 48:2861-2864. [PMID: 37262229 DOI: 10.1364/ol.485939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 04/25/2023] [Indexed: 06/03/2023]
Abstract
InGaN-based micro-LEDs can detect and emit optical signals simultaneously, owing to their overlapping emission and absorption spectra, enabling color detection. In this paper, we fabricated a green InGaN-based micro-LED array with integrated emission and detection functions. On the back side of the integrated device, when the 80 μm micro-LED emitted light, the 200 μm LED could receive reflected light to accomplish color detection. The spacing between the 80 μm and the 200 μm micro-LEDs was optimized to be 1 mm to reduce the effect of the direct light transmitted through the n-GaN layer without reflection. The integrated device shows good detection performance for different colors and skin colors, even in a dark environment. In addition, light can be emitted from the top side of the device. Utilization of light from both sides of the integrated device provides the possibility of its application in display, communication, and detection on the different sides.
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Lyu Y, Tschulakow AV, Wang K, Brash DE, Schraermeyer U. Chemiexcitation and melanin in photoreceptor disc turnover and prevention of macular degeneration. Proc Natl Acad Sci U S A 2023; 120:e2216935120. [PMID: 37155898 PMCID: PMC10194005 DOI: 10.1073/pnas.2216935120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 04/03/2023] [Indexed: 05/10/2023] Open
Abstract
Age-related macular degeneration, Stargardt disease, and their Abca4-/- mouse model are characterized by accelerated accumulation of the pigment lipofuscin, derived from photoreceptor disc turnover in the retinal pigment epithelium (RPE); lipofuscin accumulation and retinal degeneration both occur earlier in albino mice. Intravitreal injection of superoxide (O2•-) generators reverses lipofuscin accumulation and rescues retinal pathology, but neither the target nor mechanism is known. Here we show that RPE contains thin multi-lamellar membranes (TLMs) resembling photoreceptor discs, which associate with melanolipofuscin granules in pigmented mice but in albinos are 10-fold more abundant and reside in vacuoles. Genetically over-expressing tyrosinase in albinos generates melanosomes and decreases TLM-related lipofuscin. Intravitreal injection of generators of O2•- or nitric oxide (•NO) decreases TLM-related lipofuscin in melanolipofuscin granules of pigmented mice by ~50% in 2 d, but not in albinos. Prompted by evidence that O2•- plus •NO creates a dioxetane on melanin that excites its electrons to a high-energy state (termed "chemiexcitation"), we show that exciting electrons directly using a synthetic dioxetane reverses TLM-related lipofuscin even in albinos; quenching the excited-electron energy blocks this reversal. Melanin chemiexcitation assists in safe photoreceptor disc turnover.
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Affiliation(s)
- Yanan Lyu
- Division of Experimental Vitreoretinal Surgery, Centre for Ophthalmology, University of Tuebingen, Tuebingen72076, Germany
| | - Alexander V. Tschulakow
- Division of Experimental Vitreoretinal Surgery, Centre for Ophthalmology, University of Tuebingen, Tuebingen72076, Germany
- OcuTox GmbH, Preclinical Drug Assessment, Hechingen72379, Germany
| | - Kun Wang
- Division of Experimental Vitreoretinal Surgery, Centre for Ophthalmology, University of Tuebingen, Tuebingen72076, Germany
| | - Douglas E. Brash
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT06520-8040
- Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, CT06520-8028
| | - Ulrich Schraermeyer
- Division of Experimental Vitreoretinal Surgery, Centre for Ophthalmology, University of Tuebingen, Tuebingen72076, Germany
- OcuTox GmbH, Preclinical Drug Assessment, Hechingen72379, Germany
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Brănișteanu DE, Porumb-Andrese E, Stărică A, Munteanu AC, Toader MP, Zemba M, Porumb V, Cozmin M, Moraru AD, Nicolescu AC, Brănișteanu DC. Differences and Similarities in Epidemiology and Risk Factors for Cutaneous and Uveal Melanoma. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:medicina59050943. [PMID: 37241175 DOI: 10.3390/medicina59050943] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 04/17/2023] [Accepted: 05/12/2023] [Indexed: 05/28/2023]
Abstract
Both cutaneous melanoma (CM) and uveal melanoma (UM) represent important causes of morbidity and mortality. In this review, we evaluate the available knowledge on the differences and similarities between cutaneous melanoma and uveal melanoma, focusing on the epidemiological aspects and risk factors. Uveal melanoma is a rare condition but is the most prevalent primary intra-ocular malignant tumor in adults. Cutaneous melanoma, on the other hand, is significantly more common. While the frequency of cutaneous melanoma has increased in the last decades worldwide, the incidence of uveal melanoma has remained stable. Although both tumors arise from melanocytes, they are very distinct entities biologically, with complex and varied etiologies. Both conditions are encountered more frequently by individuals with a fair phenotype. ultraviolet-radiation is an important, well-documented risk factor for the development of CM, but has shown not to be of specific risk in UM. Although cutaneous and ocular melanomas seem to be inherited independently, there are reported cases of concomitant primary tumors in the same patient.
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Affiliation(s)
- Daciana Elena Brănișteanu
- Dermatology Department, 'Grigore T. Popa' University of Medicine and Pharmacy, 700115 Iasi, Romania
- Railway Clinical Hospital, 700506 Iasi, Romania
| | - Elena Porumb-Andrese
- Dermatology Department, 'Grigore T. Popa' University of Medicine and Pharmacy, 700115 Iasi, Romania
- Railway Clinical Hospital, 700506 Iasi, Romania
| | - Alexandra Stărică
- Dermatology Department, 'Grigore T. Popa' University of Medicine and Pharmacy, 700115 Iasi, Romania
- Railway Clinical Hospital, 700506 Iasi, Romania
| | - Anca Catalina Munteanu
- Dermatology Department, 'Grigore T. Popa' University of Medicine and Pharmacy, 700115 Iasi, Romania
- Railway Clinical Hospital, 700506 Iasi, Romania
| | | | - Mihail Zemba
- Ophthalmology Department, 'Carol Davila' University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Vlad Porumb
- Department Surgery, 'Grigore T. Popa' University of Medicine and Pharmacy, 700111 Iasi, Romania
| | - Mihai Cozmin
- Clinical Department, Apollonia University of Iasi, 700511 Iasi, Romania
| | - Andreea Dana Moraru
- Ophthalmology Department, 'Grigore T. Popa' University of Medicine and Pharmacy, 700115 Iasi, Romania
| | - Alin Codruț Nicolescu
- Roma Medical Center for Diagnosis and Treatment, 011773 Bucharest, Romania
- "Agrippa Ionescu" Emergency Clinical Hospital, 011773 Bucharest, Romania
| | - Daniel Constantin Brănișteanu
- Railway Clinical Hospital, 700506 Iasi, Romania
- Ophthalmology Department, 'Grigore T. Popa' University of Medicine and Pharmacy, 700115 Iasi, Romania
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12
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Structural Investigation of DHICA Eumelanin Using Density Functional Theory and Classical Molecular Dynamics Simulations. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238417. [PMID: 36500509 PMCID: PMC9738096 DOI: 10.3390/molecules27238417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 12/05/2022]
Abstract
Eumelanin is an important pigment, for example, in skin, hair, eyes, and the inner ear. It is a highly heterogeneous polymer with 5,6-dihydroxyindole-2-carboxylic acid (DHICA) and 5,6-dihydroxyindole (DHI) building blocks, of which DHICA is reported as the more abundant in natural eumelanin. The DHICA-eumelanin protomolecule consists of three building blocks, indole-2-carboxylic acid-5,6-quinone (ICAQ), DHICA and pyrrole-2,3,5-tricarboxylic acid (PTCA). Here, we focus on the self-assembly of DHICA-eumelanin using multi-microsecond molecular dynamics (MD) simulations at various concentrations in aqueous solutions. The molecule was first parameterized using density functional theory (DFT) calculations. Three types of systems were studied: (1) uncharged DHICA-eumelanin, (2) charged DHICA-eumelanin corresponding to physiological pH, and (3) a binary mixture of both of the above protomolecules. In the case of uncharged DHICA-eumelanin, spontaneous aggregation occurred and water molecules were present inside the aggregates. In the systems corresponding to physiological pH, all the carboxyl groups are negatively charged and the DHICA-eumelanin model has a net charge of -4. The effect of K+ ions as counterions was investigated. The results show high probability of binding to the deprotonated oxygens of the carboxylate anions in the PTCA moiety. Furthermore, the K+ counterions increased the solubility of DHICA-eumelanin in its charged form. A possible explanation is that the charged protomolecules favor binding to the K+ ions rather than aggregating and binding to other protomolecules. The binary mixtures show aggregation of uncharged DHICA-eumelanins; unlike the charged systems with no aggregation, a few charged DHICA-eumelanins are present on the surface of the uncharged aggregation, binding to the K+ ions.
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13
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Fietz A, Hurst J, Schnichels S. Out of the Shadow: Blue Light Exposure Induces Apoptosis in Müller Cells. Int J Mol Sci 2022; 23:ijms232314540. [PMID: 36498867 PMCID: PMC9739907 DOI: 10.3390/ijms232314540] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/24/2022] Open
Abstract
Awareness toward the risks of blue light (BL) exposure is rising due to increased use of BL-enriched LEDs in displays. Short-wave BL (400-500 nm) has a high photochemical energy, leading to the enhanced production of reactive oxygen species (ROS). BL potentially plays a role in causing dry eye, cataracts, and age-related macular degeneration (AMD). The effect of BL on retinal pigment epithelium cells (RPEs) or photoreceptors has been extensively investigated. In contrast, only a few studies have investigated the effects of BL exposure on Müller cells (MCs). This is mainly due to their lack of photosensitive elements and the common assumption that their reaction to stress is only secondary in disease development. However, MCs perform important supportive, secretory, and immune functions in the retina, making them essential for retinal survival. Increased oxidative stress is a key player in many retinal diseases such as AMD or glaucoma. We hypothesize that increased oxidative stress can also affect MCs. Thus, we simulated oxidative stress levels by exposing primary porcine MCs and human MIO-M1 cells to BL. To confirm the wavelength-specificity, the cells were further exposed to red (RL), purple (PL), and white light (WL). BL and WL exposure increased ROS levels, but only BL exposure led to apoptosis in primary MCs. Thus, BL accounted for the harmful part of WL exposure. When cells were simultaneously exposed to BL and RL (i.e., PL), cell damage due to BL could be partly prevented, as could the inhibition of p53, demonstrating the protective effect of RL and p53 dependency. In contrast, BL hardly induced apoptosis in MIO-M1 cells, which is likely due to the immortalization of the cells. Therefore, enhanced oxidative stress levels can significantly harm MC function, probably leading to decreased retinal survival and, thus, further enhancing the progression of retinal diseases. Preventing the cell death of these essential retinal cells represents a promising therapy option to enhance retinal survival.
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14
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Kwon YS, Zheng M, Zhang AY, Han Z. Melanin-like Nanoparticles as an Alternative to Natural Melanin in Retinal Pigment Epithelium Cells and Their Therapeutic Effects against Age-Related Macular Degeneration. ACS NANO 2022; 16:19412-19422. [PMID: 36269679 DOI: 10.1021/acsnano.2c09087] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Melanin is a natural pigment that is widely distributed in many parts of the human body, such as the skin and retinal pigment epithelium (RPE) in eyes. In contrast to skin melanin, which is being constantly synthesized by the epidermal melanocytes, melanin in the RPE does not regenerate. Melanin is known to function as a potential radical scavenger and photoprotective agent. However, the protective effects of melanin against oxidative stress decline with increasing age. This phenomenon has been correlated with the pathogenesis of age-related macular degeneration (AMD). To increase the potential antioxidant and photoprotective characteristics of melanin, we designed a therapeutic strategy for replenishment of melanin using PEGylated synthetic melanin-like nanoparticles (MNPs) in the RPE for the treatment of AMD. We performed experiments using AMD-like cellular and mouse models and demonstrated that MNPs are biocompatible and selectively target reactive oxygen species (ROS) with powerful antioxidant properties. MNPs can traffic and accumulate in the RPE and are exclusively located in cytosol, but not the nucleus and mitochondria of the cells, for at least 3 months after a single-dose intravitreal injection. Our findings demonstrate that MNPs are able to substitute for natural melanin in the RPE and suggest the potential efficacy of MNPs as a natural radical scavenger against oxidative stress in ROS-related diseases, such as AMD.
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Affiliation(s)
- Yong-Su Kwon
- Department of Ophthalmology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina27599, United States
| | - Min Zheng
- Department of Ophthalmology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina27599, United States
| | - Alice Yang Zhang
- Department of Ophthalmology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina27599, United States
| | - Zongchao Han
- Department of Ophthalmology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina27599, United States
- Division of Pharmacoengineering & Molecular Pharmaceutics, Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina27599, United States
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15
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Lee CH, Lee H, Lee SM, Choi EY, Lee J, Kim M. Clinical and Multimodal Imaging Features of Choroidal Nevi in the Korean Population. J Clin Med 2022; 11:jcm11226666. [PMID: 36431143 PMCID: PMC9698851 DOI: 10.3390/jcm11226666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/06/2022] [Accepted: 11/07/2022] [Indexed: 11/13/2022] Open
Abstract
Choroidal nevus is a precursor of choroidal melanoma. Multimodal imaging has become vital in predicting the malignant transformation of choroidal nevi. This single-center, retrospective study analyzed clinical characteristics and multimodal imaging findings of 168 choroidal nevi (164 patients) of the Korean population. The mean age at presentation was 50 ± 15 (range, 13−85) (women, n = 88 [53.7%]). Choroidal nevi (melanotic, n = 164 [97.6%]; postequatorial, n = 160 [95.2%]) were densely located between the optic disc and foveola (65.5%). The mean maximum linear basal diameter on fundus photography and thickness on optical coherence tomography were 2.97 ± 1.51 mm and 521 ± 297 μm, respectively. On ultrasonography, the mean thickness was 0.87 ± 0.60 mm. Choroidal nevi in women were associated with a higher maximum linear basal diameter (3.23 ± 1.65 vs. 2.68 ± 1.21 mm; p = 0.033) and age at diagnosis (52 ± 14 vs. 47 ± 16 years; p = 0.046) than those in men. Choroidal nevi with associated subretinal fluid (23.2%) presented with larger basal diameter (p = 0.049) and thickness on B-scan and optical coherence tomography (p < 0.001), but a younger age at diagnosis (p < 0.001) than those of dry nevi. This multimodal imaging study of choroidal nevi revealed some distinct characteristics, including topographic distribution, sex-related differences, and a younger age at diagnosis of nevi with fluid.
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Affiliation(s)
| | | | | | | | | | - Min Kim
- Correspondence: ; Tel.: +82-2-2019-3440
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16
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Fantaguzzi F, Zucchiatti I, Sacconi R, Bux AV, Prascina F, Bandello F, Querques G. Bilateral asymptomatic macular hypopigmentation in a young woman: multimodal imaging and pathogenetic hypothesis. Am J Ophthalmol Case Rep 2022; 28:101725. [PMCID: PMC9589140 DOI: 10.1016/j.ajoc.2022.101725] [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: 06/02/2022] [Revised: 10/06/2022] [Accepted: 10/09/2022] [Indexed: 11/25/2022] Open
Abstract
Purpose Observations Conclusions
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Affiliation(s)
- Federico Fantaguzzi
- Department of Ophthalmology, University Vita-Salute, IRCCS San Raffaele, Milan, Italy
| | - Ilaria Zucchiatti
- Department of Ophthalmology, University Vita-Salute, IRCCS San Raffaele, Milan, Italy
| | - Riccardo Sacconi
- Department of Ophthalmology, University Vita-Salute, IRCCS San Raffaele, Milan, Italy
| | - Anna Valeria Bux
- Department of Ophthalmology, University of Foggia, Foggia, Italy
| | - Francesco Prascina
- Department of Ophthalmology, University Vita-Salute, IRCCS San Raffaele, Milan, Italy
| | - Francesco Bandello
- Department of Ophthalmology, University Vita-Salute, IRCCS San Raffaele, Milan, Italy
| | - Giuseppe Querques
- Department of Ophthalmology, University Vita-Salute, IRCCS San Raffaele, Milan, Italy,Corresponding author.
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17
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Pandey RS, Krebs MP, Bolisetty MT, Charette JR, Naggert JK, Robson P, Nishina PM, Carter GW. Single-Cell RNA Sequencing Reveals Molecular Features of Heterogeneity in the Murine Retinal Pigment Epithelium. Int J Mol Sci 2022; 23:10419. [PMID: 36142331 PMCID: PMC9499471 DOI: 10.3390/ijms231810419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 08/09/2022] [Accepted: 09/05/2022] [Indexed: 11/16/2022] Open
Abstract
Transcriptomic analysis of the mammalian retinal pigment epithelium (RPE) aims to identify cellular networks that influence ocular development, maintenance, function, and disease. However, available evidence points to RPE cell heterogeneity within native tissue, which adds complexity to global transcriptomic analysis. Here, to assess cell heterogeneity, we performed single-cell RNA sequencing of RPE cells from two young adult male C57BL/6J mice. Following quality control to ensure robust transcript identification limited to cell singlets, we detected 13,858 transcripts among 2667 and 2846 RPE cells. Dimensional reduction by principal component analysis and uniform manifold approximation and projection revealed six distinct cell populations. All clusters expressed transcripts typical of RPE cells; the smallest (C1, containing 1-2% of total cells) exhibited the hallmarks of stem and/or progenitor (SP) cells. Placing C1-6 along a pseudotime axis suggested a relative decrease in melanogenesis and SP gene expression and a corresponding increase in visual cycle gene expression upon RPE maturation. K-means clustering of all detected transcripts identified additional expression patterns that may advance the understanding of RPE SP cell maintenance and the evolution of cellular metabolic networks during development. This work provides new insights into the transcriptome of the mouse RPE and a baseline for identifying experimentally induced transcriptional changes in future studies of this tissue.
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Affiliation(s)
- Ravi S. Pandey
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Dr., Farmington, CT 06032, USA
| | - Mark P. Krebs
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
| | - Mohan T. Bolisetty
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Dr., Farmington, CT 06032, USA
| | | | | | - Paul Robson
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Dr., Farmington, CT 06032, USA
| | - Patsy M. Nishina
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
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18
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Feldman TB, Dontsov AE, Yakovleva MA, Ostrovsky MA. Photobiology of lipofuscin granules in the retinal pigment epithelium cells of the eye: norm, pathology, age. Biophys Rev 2022; 14:1051-1065. [PMID: 36124271 PMCID: PMC9481861 DOI: 10.1007/s12551-022-00989-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 07/26/2022] [Indexed: 01/10/2023] Open
Abstract
Lipofuscin granules (LGs) are accumulated in the retinal pigment epithelium (RPE) cells. The progressive LG accumulation can somehow lead to pathology and accelerate the aging process. The review examines composition, spectral properties and photoactivity of LGs isolated from the human cadaver eyes. By use of atomic force microscopy and near-field microscopy, we have revealed the fluorescent heterogeneity of LGs. We have discovered the generation of reactive oxygen species by LGs, and found that LGs and melanolipofuscin granules are capable of photoinduced oxidation of lipids. It was shown that A2E, as the main fluorophore (bisretinoid) of LGs, is much less active as an oxidation photosensitizer than other fluorophores (bisretinoids) of LGs. Photooxidized products of bisretinoids pose a much greater danger to the cell than non-oxidized one. Our studies of the fluorescent properties of LGs and their fluorophores (bisretinoids) showed for the first time that their spectral characteristics change (shift to the short-wavelength region) in pathology and after exposure to ionizing radiation. By recording the fluorescence spectra and fluorescence decay kinetics of oxidized products of LG fluorophores, it is possible to improve the methods of early diagnosis of degenerative diseases. Lipofuscin ("aging pigment") is not an inert "slag". The photoactivity of LGs can pose a significant danger to the RPE cells. Fluorescence characteristics of LGs are a tool to detect early stages of degeneration in the retina and RPE.
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Affiliation(s)
- T. B. Feldman
- Department of Biology, Lomonosov Moscow State University, Moscow, Russia
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - A. E. Dontsov
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - M. A. Yakovleva
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - M. A. Ostrovsky
- Department of Biology, Lomonosov Moscow State University, Moscow, Russia
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, Russia
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19
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Evaluation of choroidal melanin-containing tissue in healthy Japanese subjects by polarization-sensitive optical coherence tomography. Sci Rep 2022; 12:4048. [PMID: 35260673 PMCID: PMC8904585 DOI: 10.1038/s41598-022-07818-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 02/24/2022] [Indexed: 11/08/2022] Open
Abstract
In this study, the choroidal melanin content in healthy eyes was evaluated with polarization-sensitive optical coherence tomography (PS-OCT). We evaluated 105 healthy eyes of 105 Japanese subjects. The mean thickness of melanin-containing tissue in the choroid (thickness of MeCh) and the choroidal melanin occupancy rate within a 5-mm circular region from the foveal center were calculated using the degree of polarization uniformity obtained by PS-OCT and compared with the choroidal thickness, patient age, and axial length. To evaluate regional variations, the 5-mm circular region was divided into a center area and an outer ring area, and the outer ring area was further divided into four areas (nasal, temporal, superior, and inferior). The mean thickness of MeCh showed a significant positive correlation with the choroidal thickness. The mean choroidal melanin occupancy rate showed a significant positive correlation with age. The mean choroidal melanin occupancy rate of the center area was significantly larger than that of the outer ring area. The mean thickness of MeCh and choroidal melanin occupancy rate of the nasal area were significantly lower than those of other areas. The distribution of melanin-containing tissue in the choroid varies significantly with age and location.
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20
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Soltani S, Sowlati-Hashjin S, Tetsassi Feugmo CG, Karttunen M. Free Energy and Stacking of Eumelanin Nanoaggregates. J Phys Chem B 2022; 126:1805-1818. [PMID: 35175060 DOI: 10.1021/acs.jpcb.1c07884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Eumelanin, a member of the melanin family, is a black-brown insoluble pigment. It possesses a broad range of properties such as antioxidation, free radical scavenging, photoprotection, and charge carrier transportation. Surprisingly, the exact molecular structure of eumelanin remains undefined. It is, however, generally considered to consist of two main building blocks, 5,6-dihydroxyindole (DHI) and 5,6- dihydroxyindole carboxylic acid (DHICA). We focus on DHI and report, for the first time, a computational investigation of the structural properties of DHI-eumelanin aggregates in aqueous solutions. First, multimicrosecond molecular dynamics (MD) simulations at different concentrations were performed to investigate the aggregation and ordering of tetrameric DHI-eumelanin protomolecules. This was followed by umbrella sampling (US) and density functional theory (DFT) calculations to study the physical mechanisms of stacking. Aggregation occurs through formation of nanoscale stacks and was observed in all systems. Further analyses showed that aggregation and coarsening of the domains is due to a decrease in hydrogen bonds between the eumelanins and water; while domains exist, there is no long-range order. The results show noncovalent stacks with the interlayer distance between eumelanin protomolecules being less than 3.5 Å. This is in good agreement with transmission electron microscopy data. Both free energy calculations and DFT revealed strong stacking interactions. The electrostatic potential map provides an explanation and a rationale for the slightly sheared relative orientations and, consequently, for the curved shapes of the nanoscale domains.
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Affiliation(s)
- Sepideh Soltani
- Department of Physics and Astronomy, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada.,The Centre of Advanced Materials and Biomaterials Research, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada
| | - Shahin Sowlati-Hashjin
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario M5S 3G9, Canada
| | - Conrard Giresse Tetsassi Feugmo
- National Research Council Canada, Energy Mining and Environment, Mississauga, Ontario L5K 1B1, Canada.,Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada
| | - Mikko Karttunen
- The Centre of Advanced Materials and Biomaterials Research, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada.,Department of Physics and Astronomy, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada.,Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada
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21
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Istrate M, Hasbei-Popa M, Iliescu DA, Ghiță AC, Vlaicu B, Ghiță MA. Dual Sensory Impairment: The Correlation between Age Related Macular Degeneration and Sensorineural Hearing Loss. Medicina (B Aires) 2022; 58:medicina58020291. [PMID: 35208614 PMCID: PMC8877232 DOI: 10.3390/medicina58020291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 01/30/2022] [Accepted: 02/09/2022] [Indexed: 11/28/2022] Open
Abstract
The pathogeneses of age-related macular degeneration (AMD) and age-related hearing impairment are not yet fully understood. If AMD and age-related hearing impairment are correlated, the cause of both may be a result of a common vulnerability. The aim of this study was to assess the interrelation between age-related macular degeneration and age-related hearing loss. Material and methods: In our case-control analysis, the hearing conditions of 40 subjects with AMD were compared with 40 age-matched healthy controls. In all patients, retinal changes were certified by clinical examinations, optical coherence tomography (OCT), and fluorescein angiography (FA). All subjects were inspected with pure tone audiometry (PTA), impedance audiometry, and speech audiometry. Results: A significant correlation (p < 0.001) was identified between age-related macular degeneration and age-related hearing impairment. The predominant hearing impairment in this case was sensorineural (SNHL). Of the patients diagnosed with AMD, SNHL was found in 88.89% of those with exudative macular degeneration and in 67.74% of those with atrophic macular degeneration. In contrast, we found that a significant proportion of the control group had normal hearing. Conclusion: One possible explanation for the association between retinal and cochlear impairment may be due to a melanin disorder.
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Affiliation(s)
- Marina Istrate
- Department of Doctoral School, “Victor Babes” University of Medicine and Pharmacy, 300041 Timisoara, Romania
- Department of Ophthalmology, “Infosan” Ophthalmology Clinic, 010538 Bucharest, Romania
- Correspondence:
| | - Mihai Hasbei-Popa
- Department of Medicine, “Iuliu Hatieganu” University of Medicine and Pharmacy, 400000 Cluj-Napoca, Romania
| | - Daniela Adriana Iliescu
- Department of Physiology, ”Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Ophtalmology, ”Ocularcare” Eye Clinic, 012244 Bucharest, Romania
| | - Ana Cristina Ghiță
- Department of Ophtalmology, ”Ocularcare” Eye Clinic, 012244 Bucharest, Romania
| | - Brigitha Vlaicu
- Department of Hygiene, ”Victor Babes” University of Medicine and Pharmacy, 300041 Timisoara, Romania
| | - Mihai Aurelian Ghiță
- Department of Physiology, ”Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Ophtalmology, ”Ocularcare” Eye Clinic, 012244 Bucharest, Romania
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22
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Berrocal AM, Fan KC, Al-Khersan H, Negron CI, Murray T. Retinopathy of Prematurity: Advances in the Screening and Treatment of Retinopathy of Prematurity Using a Single Center Approach. Am J Ophthalmol 2022; 233:189-215. [PMID: 34298009 PMCID: PMC8697761 DOI: 10.1016/j.ajo.2021.07.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 06/30/2021] [Accepted: 07/15/2021] [Indexed: 01/03/2023]
Abstract
PURPOSE To focus on the longitudinal evaluation of high-risk infants for the development of retinopathy of prematurity (ROP) at a single tertiary neonatal intensive care unit (NICU), and to evaluate evolving demographics of ROP and the transition of treatment-warranted disease. DESIGN Retrospective cohort study. METHODS A consecutive retrospective review was performed of all infants screened for ROP between 1990 and 2019 at the Jackson Memorial Hospital neonatal intensive care unit. All inborn infants meeting a birth criteria of <32 weeks' gestational age (GA) or a birthweight (BW) of 1500 g were included. Longitudinal demographic, diagnostic, and treatment data were reported. RESULTS Between January 1, 1990, and June 20, 2019, a total of 25,567 examinations were performed and 7436 patients were included. Longitudinal trends over 3 decades demonstrated a decreasing incidence of ROP (P < .05). Although the mean BW and GA increased over 3 decades, patients with ROP demonstrated lower BW and GA over time (P < .05). The prevalence of micro-premature infants (as defined by BW <750 g) continues to rise over time. Micro-preemies demonstrated increasing severity of zone and stage grading, plus disease, and propensity to require treatment (P < .05). The rate of progression of ROP to stage 4 and 5 disease has decreased over time, and there has been an associated increased adoption of intravitreal bevacizumab as primary and salvage therapy. CONCLUSIONS Understanding the evolution of ROP infants and treatment over time is critical in identifying high-risk infants and in reducing the incidence of severe-stage ROP. Micro-prematurity is one of the significant risk factors for treatment-warranted ROP that continues to increase as neonatal care improves. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.
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Affiliation(s)
- Audina M Berrocal
- Department of Ophthalmology (A.M.B, K.C.F., H.A.-K., C.I.N.), Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, Florida, USA.
| | - Kenneth C Fan
- Department of Ophthalmology (A.M.B, K.C.F., H.A.-K., C.I.N.), Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Hasenin Al-Khersan
- Department of Ophthalmology (A.M.B, K.C.F., H.A.-K., C.I.N.), Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Catherin I Negron
- Department of Ophthalmology (A.M.B, K.C.F., H.A.-K., C.I.N.), Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Timothy Murray
- Murray Oncology and Retina (T.M.), South Miami, Florida, USA
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Dahlstrand U, Merdasa A, Hult J, Albinsson J, Cinthio M, Sheikh R, Malmsjö M. Photoacoustic Imaging of Enucleated Eyes from Patients with Uveal Melanoma can Reveal Extrascleral Growth. Open Ophthalmol J 2021. [DOI: 10.2174/1874364102115010270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Background:
Uveal melanoma is treated by either enucleation (removal of the eye) or local eye-sparing therapies, depending on tumor size and whether there are signs of extrascleral growth. Photoacoustic (PA) imaging is a novel imaging modality that provides high-resolution images of the molecular composition of tissues.
Objective:
In this study, the feasibility of PA imaging for uveal melanomas and detection of extrascleral growth was explored.
Methods:
Seven enucleated human eyes with uveal melanomas were examined using PA imaging. The spectral signatures of the melanomas and the layers of the normal eyewall were characterized using 59 excitation wavelengths from 680 to 970 nm.
Results:
Significant differences were seen between the spectra obtained from melanoma and the healthy eyewall. Using spectral unmixing, melanin, hemoglobin and collagen could be mapped out, showing the architecture of the tumor in relation to the eyewall. This allowed visualization of regions where the tumor extended into the extrascleral space.
Conclusion:
PA imaging appears to have the potential to aid in assessing uveal melanomas and as a diagnostic tool for the detection of extrascleral growth.
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Nag TC, Gorla S, Kumari C, Roy TS. Aging of the human choriocapillaris: Evidence that early pericyte damage can trigger endothelial changes. Exp Eye Res 2021; 212:108771. [PMID: 34624336 DOI: 10.1016/j.exer.2021.108771] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 08/15/2021] [Accepted: 09/17/2021] [Indexed: 01/25/2023]
Abstract
The choriocapillaris (CC), the capillary bed in the choroid, essentially nourishes the photoreceptor cells. Its damage in aging and age-related diseases significantly influences the survival of the photoreceptor cells. Earlier reports implicated endothelial loss in aged and diseased CC; however, age-related pericyte changes and their contribution in CC death remain unknown. We examined human donor eyes (age: 56-94 years; N = 24), and found that CC pericyte damage preceded endothelial changes. With aging (>70 years), the sub-macular choroid accumulated debris in Bruch's membrane (BM). Of the debris content, the long-spaced collagens had a tendency to settle over the capillary basal lamina (BL), and this often resulted in endothelial projection into capillary lumen. Between 75 and 83 years, pericytes contained dark mitochondria, and their processes facing the BM debris showed partial loss of BL and intermediate filaments (IFs), when the endothelium remained unaltered. The endothelial changes appeared beyond 83 years, the abundance of IFs and autophagy reinforced their survival until late aging. TUNEL+ pericytes, and immunoreactivity to carboxymethyl lysine and 4-hydroxy 2-nonenal, but no nitro-tyrosine, was detected in aged CC walls. Iba-1+ dystrophic microglia were present in the vicinity of the CC. Our data indicate that (1) BM debris exerts pressure on the CC, leading to the damage of the capillary BL and pericyte processes (2) loss of IFs results in early pericyte destabilization (3) capillary wall undergoes lipid peroxidative and glycative damage, and (4) pericyte damage leads to late endothelial changes and ultimately CC loss. Future research should explore the normal ways of pericyte maintenance in the aging nervous system.
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Affiliation(s)
- Tapas Chandra Nag
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi, 110029, India.
| | - Shilpa Gorla
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Chiman Kumari
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Tara Sankar Roy
- Department of Anatomy, All India Institute of Medical Sciences, New Delhi, 110029, India
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25
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Sato T, Takeuchi M, Karasawa Y, Ito M. Profiles of Cytokines Secreted by ARPE-19 Cells Exposed to Light and Incubated with Anti-VEGF Antibody. Biomedicines 2021; 9:biomedicines9101333. [PMID: 34680450 PMCID: PMC8533158 DOI: 10.3390/biomedicines9101333] [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: 08/24/2021] [Revised: 09/18/2021] [Accepted: 09/20/2021] [Indexed: 11/16/2022] Open
Abstract
The retinal pigment epithelium (RPE) is the major source of cytokines in the retina regulating the intraocular immune environment, and a primary target of photodamage. Here, we examined 27 types of cytokines secreted by ARPE-19 cells exposed to visible light and incubated with aflibercept or ranibizumab, which are two anti-vascular endothelial growth factor (VEGF) antibodies. The cells were cultured for 24 h in the dark or under 2000 lux irradiation from a daylight-colored fluorescent lamp, and cytokine levels in the culture supernatant were measured. In the light-irradiated culture, the levels of IL-9, IL-17A and bFGF were higher, and the levels of IL-6, IL-7, IL-8 and MCP-1 were lower than those in the dark culture, while there was no significant difference with the VEGF-A level. In subgroup analyses of the light-irradiated culture, the bFGF level under 250 to 2000 lux irradiation was elevated in a light intensity-dependent manner. In culture exposed to blue, green or red light, the bFGF level was elevated by blue light and was high compared to that by green or red light. In culture with aflibercept or ranibizumab in the dark, the levels of IL-6, IL-8, bFGF and MCP-1 were increased, and the IL-12 level decreased synchronously with a reduction in the VEGF-A level. Our findings indicate that continuous irradiation of visible light and VEGF suppression may be an influential factor in expression patterns of inflammatory cytokines secreted by human RPE cells.
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Affiliation(s)
- Tomohito Sato
- Department of Ophthalmology, National Defense Medical College, Tokorozawa 359-8513, Japan; (T.S.); (Y.K.)
| | - Masaru Takeuchi
- Department of Ophthalmology, National Defense Medical College, Tokorozawa 359-8513, Japan; (T.S.); (Y.K.)
- Correspondence: ; Tel.: +81-4-2995-1683; Fax: +81-4-2993-5332
| | - Yoko Karasawa
- Department of Ophthalmology, National Defense Medical College, Tokorozawa 359-8513, Japan; (T.S.); (Y.K.)
| | - Masataka Ito
- Department of Developmental Anatomy and Regenerative Biology, National Defense Medical College, Tokorozawa 359-8513, Japan;
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Meleppat RK, Ronning KE, Karlen SJ, Burns ME, Pugh EN, Zawadzki RJ. In vivo multimodal retinal imaging of disease-related pigmentary changes in retinal pigment epithelium. Sci Rep 2021; 11:16252. [PMID: 34376700 PMCID: PMC8355111 DOI: 10.1038/s41598-021-95320-z] [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: 06/04/2021] [Accepted: 07/20/2021] [Indexed: 02/08/2023] Open
Abstract
Melanosomes, lipofuscin, and melanolipofuscin are the three principal types of pigmented granules found in retinal pigment epithelium (RPE) cells. Changes in the density of melanosomes and lipofuscin in RPE cells are considered hallmarks of various retinal diseases, including Stargardt disease and age-related macular degeneration (AMD). Herein, we report the potential of an in vivo multimodal imaging technique based on directional back-scattering and short-wavelength fundus autofluorescence (SW-FAF) to study disease-related changes in the density of melanosomes and lipofuscin granules in RPE cells. Changes in the concentration of these granules in Abca4-/- mice (a model of Stargardt disease) relative to age-matched wild-type (WT) controls were investigated. Directional optical coherence tomography (dOCT) was used to assess melanosome density in vivo, whereas the autofluorescence (AF) images and emission spectra acquired with a spectrometer-integrated scanning laser ophthalmoscope (SLO) were used to characterize lipofuscin and melanolipofuscin granules in the same RPE region. Subcellular-resolution ex vivo imaging using confocal fluorescence microscopy and electron microscopy was performed on the same tissue region to visualize and quantify melanosomes, lipofuscin, and melanolipofuscin granules. Comparisons between in vivo and ex vivo results confirmed an increased concentration of lipofuscin granules and decreased concentration of melanosomes in the RPE of Abca4-/- mice, and provided an explanation for the differences in fluorescence and directionality of RPE scattering observed in vivo between the two mouse strains.
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Affiliation(s)
- Ratheesh K Meleppat
- UC Davis Eyepod Imaging Laboratory, University of California Davis, Davis, CA, 95616, USA
- Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA, 95616, USA
- Department of Ophthalmology and Vision Science, University of California Davis, Sacramento, CA, USA
| | - Kaitryn E Ronning
- Center for Neuroscience, University of California Davis, Davis, CA, 95618, USA
| | - Sarah J Karlen
- Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA, 95616, USA
| | - Marie E Burns
- Center for Neuroscience, University of California Davis, Davis, CA, 95618, USA
- Department of Ophthalmology and Vision Science, University of California Davis, Sacramento, CA, USA
| | - Edward N Pugh
- UC Davis Eyepod Imaging Laboratory, University of California Davis, Davis, CA, 95616, USA
- Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA, 95616, USA
| | - Robert J Zawadzki
- UC Davis Eyepod Imaging Laboratory, University of California Davis, Davis, CA, 95616, USA.
- Department of Cell Biology and Human Anatomy, University of California Davis, Davis, CA, 95616, USA.
- Department of Ophthalmology and Vision Science, University of California Davis, Sacramento, CA, USA.
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27
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Understanding the way eumelanin works: A unique example of properties and skills driven by molecular heterogeneity. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123952] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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28
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Fujita A, Amari T, Ueda K, Azuma K, Inoue T, Komatsu K, Yamamoto M, Aoki N, Yamanari M, Sugiyama S, Aihara M, Kato S, Obata R. Three-Dimensional Distribution Of Fundus Depolarization and Associating Factors Measured Using Polarization-Sensitive Optical Coherence Tomography. Transl Vis Sci Technol 2021; 10:30. [PMID: 34003915 PMCID: PMC7900852 DOI: 10.1167/tvst.10.2.30] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Purpose To investigate the three-dimensional distribution and associating demographic factors of depolarization, using polarization-sensitive optical coherence tomography (PS-OCT), to evaluate melanin pigmentation in the retinal pigment epithelium (RPE) and choroid in healthy eyes. Methods In total, 39 unaffected healthy eyes of 39 subjects were examined using a PS-OCT clinical prototype. The degree of depolarization, expressed as the polarimetric entropy, was assessed in the RPE, the superficial and the total choroid layer, especially in the center, the inner, or the outer areas centered at the fovea. The values and their association with the demographic data were analyzed. Near-infrared fundus autofluorescence (NIRAF) was also used, in the same manner, for the comparison. Twenty-eight of 39 eyes were measured twice to evaluate intrasession repeatability. Results Both the polarimetric entropy in the RPE and the gray level in NIRAF, decreased from the center to the periphery (P < 0.001). The polarimetric entropy in the RPE was significantly associated with age in each area (P ≤ 0.001). In the RPE and the superficial choroid, the polarimetric entropy was negatively associated with axial length in each area (P ≤ 0.002). The intraclass correlation coefficient of the polarimetric entropy in the same session was excellent in each area of the RPE, superficial choroid, or total choroid layer (0.94–0.98). Conclusions The distribution of fundus melanin pigment-related depolarization was evaluated using PS-OCT. The depolarization was associated with the subjects’ demographic data, such as age or axial length. Translational Relevance The presented information in healthy eyes provides an essential basis for the investigation into a variety of chorioretinal pathologies.
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Affiliation(s)
- Asahi Fujita
- Department of Ophthalmology, The University of Tokyo Hospital, Tokyo, Japan.,Tokyo Metropolitan Geriatric Hospital, Tokyo, Japan
| | - Tatsuaki Amari
- Department of Ophthalmology, The University of Tokyo Hospital, Tokyo, Japan.,Eguchi Eye Hospital, Hakodate, Japan
| | - Kohei Ueda
- Department of Ophthalmology, The University of Tokyo Hospital, Tokyo, Japan
| | - Keiko Azuma
- Department of Ophthalmology, The University of Tokyo Hospital, Tokyo, Japan
| | - Tatsuya Inoue
- Department of Ophthalmology, The University of Tokyo Hospital, Tokyo, Japan.,Department of Ophthalmology, Yokohama City University Medical Center, Yokohama, Japan
| | - Kayoko Komatsu
- Department of Ophthalmology, The University of Tokyo Hospital, Tokyo, Japan
| | - Motoshi Yamamoto
- Department of Ophthalmology, The University of Tokyo Hospital, Tokyo, Japan
| | | | | | | | - Makoto Aihara
- Department of Ophthalmology, The University of Tokyo Hospital, Tokyo, Japan
| | - Satoshi Kato
- Department of Ophthalmology, The University of Tokyo Hospital, Tokyo, Japan
| | - Ryo Obata
- Department of Ophthalmology, The University of Tokyo Hospital, Tokyo, Japan
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29
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30
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Meleppat RK, Ronning KE, Karlen SJ, Kothandath KK, Burns ME, Pugh EN, Zawadzki RJ. In Situ Morphologic and Spectral Characterization of Retinal Pigment Epithelium Organelles in Mice Using Multicolor Confocal Fluorescence Imaging. Invest Ophthalmol Vis Sci 2021; 61:1. [PMID: 33137194 PMCID: PMC7645167 DOI: 10.1167/iovs.61.13.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Purpose To investigate the major organelles of the retinal pigment epithelium (RPE) in wild-type (WT, control) mice and their changes in pigmented Abca4 knockout (Abca4−/−) mice with in situ morphologic, spatial, and spectral characterization of live ex vivo flat-mounted RPE using multicolor confocal fluorescence microscopy (MCFM). Methods In situ imaging of RPE flat-mounts of agouti Abca4−/− (129S4), agouti WT (129S1/SvlmJ) controls, and B6 albino mice (C57BL/6J-Tyrc-Brd) was performed with a Nikon A1 confocal microscope. High-resolution confocal image z-stacks of the RPE cell mosaic were acquired with four different excitation wavelengths (405 nm, 488 nm, 561 nm, and 640 nm). The autofluorescence images of RPE, including voxel-by-voxel emission spectra, were acquired and processed with Nikon NIS-AR Elements software. Results The 3-dimensional multicolor confocal images provided a detailed visualization of the RPE cell mosaic, including its melanosomes and lipofuscin granules, and their varying characteristics in the different mice strains. The autofluorescence spectra, spatial distribution, and morphologic features of melanosomes and lipofuscin granules were measured. Increased numbers of lipofuscin and reduced numbers of melanosomes were observed in the RPE of Abca4−/− mice relative to controls. Conclusions A detailed assessment of the RPE autofluorescent granules and their changes ex vivo was possible with MCFM. For all excitation wavelengths, autofluorescence from the RPE cells was predominantly contributed by lipofuscin granules, while melanosomes were found to be essentially nonfluorescent. The red shift of the emission peak confirmed the presence of multiple chromophores within lipofuscin granules. The elevated autofluorescence levels in Abca4−/− mice correlated well with the increased number of lipofuscin granules.
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Affiliation(s)
- Ratheesh K Meleppat
- UC Davis Eyepod Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, California, United States.,Department of Ophthalmology & Vision Science, University of California Davis, Davis, California, United States
| | - Kaitryn E Ronning
- Center for Neuroscience, University of California Davis, Davis, California, United States
| | - Sarah J Karlen
- Department of Cell Biology and Human Anatomy, University of California Davis, Davis, California, United States
| | - Karuna K Kothandath
- UC Davis Eyepod Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, California, United States.,Department of Ophthalmology & Vision Science, University of California Davis, Davis, California, United States
| | - Marie E Burns
- Department of Ophthalmology & Vision Science, University of California Davis, Davis, California, United States.,Center for Neuroscience, University of California Davis, Davis, California, United States.,Department of Cell Biology and Human Anatomy, University of California Davis, Davis, California, United States
| | - Edward N Pugh
- UC Davis Eyepod Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, California, United States.,Department of Cell Biology and Human Anatomy, University of California Davis, Davis, California, United States
| | - Robert J Zawadzki
- UC Davis Eyepod Imaging Laboratory, Department of Cell Biology and Human Anatomy, University of California Davis, Davis, California, United States.,Department of Ophthalmology & Vision Science, University of California Davis, Davis, California, United States
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31
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Kim YC, Hsueh HT, Shin MD, Berlinicke CA, Han H, Anders NM, Hemingway A, Leo KT, Chou RT, Kwon H, Appell MB, Rai U, Kolodziejski P, Eberhart C, Pitha I, Zack DJ, Hanes J, Ensign LM. A hypotonic gel-forming eye drop provides enhanced intraocular delivery of a kinase inhibitor with melanin-binding properties for sustained protection of retinal ganglion cells. Drug Deliv Transl Res 2021; 12:826-837. [PMID: 33900546 DOI: 10.1007/s13346-021-00987-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2021] [Indexed: 12/22/2022]
Abstract
While eye drops are the most common ocular dosage form, eye drops for treating diseases of the posterior segment (retina, choroid, optic nerve) have yet to be developed. In glaucoma, eye drops are used extensively for delivering intraocular pressure (IOP)-lowering medications to the anterior segment. However, degeneration of retinal ganglion cells (RGCs) in the retina may progress despite significant IOP lowering, suggesting that a complementary neuroprotective therapy would improve glaucoma management. Here, we describe a hypotonic, thermosensitive gel-forming eye drop for effective delivery of sunitinib, a protein kinase inhibitor with activity against the neuroprotective targets dual leucine zipper kinase (DLK) and leucine zipper kinase (LZK), to enhance survival of RGCs after optic nerve injury. Further, binding of sunitinib to melanin in the pigmented cells in the choroid and retinal pigment epithelium (RPE) led to prolonged intraocular residence time, including therapeutically relevant concentrations in the non-pigmented retinal tissue where the RGCs reside. The combination of enhanced intraocular absorption provided by the gel-forming eye drop vehicle and the intrinsic melanin binding properties of sunitinib led to significant protection of RGCs with only once weekly eye drop dosing. For a chronic disease such as glaucoma, an effective once weekly eye drop for neuroprotection could result in greater patient adherence, and thus, greater disease management and improved patient quality of life.
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Affiliation(s)
- Yoo Chun Kim
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, MD, 21287, USA
| | - Henry T Hsueh
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Chemical & Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Matthew D Shin
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, MD, 21287, USA
| | - Cynthia A Berlinicke
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, MD, 21287, USA
| | - Hyounkoo Han
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, MD, 21287, USA
| | - Nicole M Anders
- The Sidney Kimmel Comprehensive Cancer Center At Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Avelina Hemingway
- The Sidney Kimmel Comprehensive Cancer Center At Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Kirby T Leo
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Renee Ti Chou
- Department of Computational Biology, Bioinformatics, and Genomics, Center for Bioinformatics and Computational Biology, University of Maryland, College Park, MD, 20742, USA
| | - HyeYoung Kwon
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Chemical & Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Matthew B Appell
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Pharmacology and Molecular Sciences, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Usha Rai
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, MD, 21287, USA
| | - Patricia Kolodziejski
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Chemical & Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Charles Eberhart
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, MD, 21287, USA
| | - Ian Pitha
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, MD, 21287, USA
| | - Donald J Zack
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, MD, 21287, USA.,Departments of Neuroscience, Molecular Biology and Genetics, and Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Justin Hanes
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, MD, 21287, USA.,Department of Chemical & Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA.,The Sidney Kimmel Comprehensive Cancer Center At Johns Hopkins University, Baltimore, MD, 21287, USA.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA.,Department of Pharmacology and Molecular Sciences, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Laura M Ensign
- Center for Nanomedicine At the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA. .,Department of Ophthalmology, Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, MD, 21287, USA. .,Department of Chemical & Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA. .,The Sidney Kimmel Comprehensive Cancer Center At Johns Hopkins University, Baltimore, MD, 21287, USA. .,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA. .,Department of Pharmacology and Molecular Sciences, Johns Hopkins University, Baltimore, MD, 21287, USA. .,Departments Gynecology and Obstetrics and Infectious Diseases, Johns Hopkins University, Baltimore, MD, 21287, USA.
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Williamson B, Pilla Reddy V. Blood retinal barrier and ocular pharmacokinetics: Considerations for the development of oncology drugs. Biopharm Drug Dispos 2021; 42:128-136. [PMID: 33759216 DOI: 10.1002/bdd.2276] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 03/09/2021] [Accepted: 03/14/2021] [Indexed: 12/12/2022]
Abstract
Tyrosine kinase inhibitors (TKIs) are an example of targeted drug therapy to treat cancer while minimizing damage to healthy tissue. In contrast to traditional oncology drugs, the toxicity profile of targeted therapies is less well understood and can include severe ocular adverse events, which are among the most common toxicity reported by these therapeutics. Inhibition of Mer receptor tyrosine kinase (MERTK) promotes innate tumor immunity by decreasing M2-macrophage polarization and efferocytosis. This mechanism offers the opportunity for targeted immunotherapy to treat cancer; however, the ocular expression of MERTK increases the difficulty for developing a targeted drug due to toxicity concerns. In this article we review the pharmacokinetic (PK) parameters and in vitro absorption, distribution, metabolism, and excretion (ADME) assays available to evaluate ocular disposition and assess the relationship between clinical PK and reported ocular events for TKIs to allow backtranslation to preclinical models. Understanding the ocular disposition in the context of PK and safety remains an evolving area and is likely to be a key aspect of developing safe and efficacious oncology drugs, devoid of ocular toxicity.
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Affiliation(s)
- Beth Williamson
- Drug Metabolism and Pharmacokinetics, Early Oncology, Oncology R&D, AstraZeneca, Cambridge, UK
| | - Venkatesh Pilla Reddy
- Modelling and Simulation, Early Oncology, Oncology R&D, AstraZeneca, Cambridge, UK.,Clinical Pharmacology and Quantitative Pharmacology, Biopharmaceuticals R&D, AstraZeneca, Cambridge, UK
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33
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Sugita S, Mandai M, Kamao H, Takahashi M. Immunological aspects of RPE cell transplantation. Prog Retin Eye Res 2021; 84:100950. [PMID: 33482342 DOI: 10.1016/j.preteyeres.2021.100950] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 01/04/2021] [Accepted: 01/11/2021] [Indexed: 01/12/2023]
Abstract
Retinal pigment epithelial (RPE) cells have several functions, including support of the neural retina and choroid in the eye and immunosuppression. Cultured human RPE cells directly suppress inflammatory immune cells. For instance, they directly suppress the activation of T cells in vitro. In contrast, transplanted allogeneic human RPE cells are rejected by bystander immune cells such as T cells in vivo. Recently, human embryonic stem cell-derived RPE cells have been used in several clinical trials, and human induced pluripotent stem cell (iPSC)-RPE cells have also been tested in our clinical study in patients with retinal degeneration. Major safety concerns after stem cell-based transplantation surgery include hyper-proliferation, tumorigenicity, or ectopic tissue formation, but these events have currently not been seen in any of these patients. However, if RPE cells are allogeneic, there are concerns about immune rejection issues that have been raised in previous clinical trials. We therefore performed a preclinical study of allogeneic iPSC-RPE cell transplantation in animal rejection models. We then conducted autogenic or allogeneic iPSC-RPE cell transplantation in clinical studies of patients with age-related macular degeneration. In this review, we focus on immunological studies of RPE cells, including iPSC-derived cells. iPSC-RPE cells have unique inflammatory (immunosuppressive and immunogenic) characteristics like primary cultured RPE cells. The purpose of this review is to summarize the current findings obtained from preclinical (basic research) and clinical studies in iPSC-RPE cell transplantation, especially the immunological aspects.
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Affiliation(s)
- Sunao Sugita
- Laboratory for Retinal Regeneration, Laboratory for Retinal Regeneration, RIKEN Center for Biosystems Dynamics Research Kobe, Japan; Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan.
| | - Michiko Mandai
- Laboratory for Retinal Regeneration, Laboratory for Retinal Regeneration, RIKEN Center for Biosystems Dynamics Research Kobe, Japan; Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
| | - Hiroyuki Kamao
- Department of Ophthalmology, Kawasaki Medical School, Okayama, Japan
| | - Masayo Takahashi
- Laboratory for Retinal Regeneration, Laboratory for Retinal Regeneration, RIKEN Center for Biosystems Dynamics Research Kobe, Japan; Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
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Bonilha VL, Bell BA, Hu J, Milliner C, Pauer GJ, Hagstrom SA, Radu RA, Hollyfield JG. Geographic Atrophy: Confocal Scanning Laser Ophthalmoscopy, Histology, and Inflammation in the Region of Expanding Lesions. Invest Ophthalmol Vis Sci 2021; 61:15. [PMID: 32658960 PMCID: PMC7425718 DOI: 10.1167/iovs.61.8.15] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Purpose To describe the pathology of AMD in eyes with geographic atrophy (GA) using confocal scanning laser ophthalmoscopy (SLO) blue light autofluorescence (BAF), and near-infrared (IR) AF and to correlate it with the histology and immunohistochemistry analysis at the margins of the GA lesion. Methods Enucleated, fixed eyes from seventeen donors with GA were imaged and analyzed by BAF-SLO, IRAF-SLO, and by fundus macroscopy (FM). Tissue from the margins of the GA lesions was cut and processed for resin embedding and histology or cryosectioning and fluorescence in the green and far-red channels, and immunohistochemistry to assess markers of inflammation. Isolated DNA from donors was genotyped for single nucleotide polymorphisms (SNPs) previously shown to be risk factors for the development and progression of AMD. Results Around the leading edge of the GA lesions we observed hypertrophic RPE cells with cytoplasm filled with granules fluorescent both in the far-red and green-red channels; abundant microglia and macrophage; deposition of complement factor H (CFH) in Bruch's membrane (BM) and increased membrane attack complex (MAC) on RPE cells. Conclusions Fluorescence imaging of cryosections of RPE cells around the leading edge of the GA lesions suggest that IRAF-SLO visualizes mostly melanin-related compounds. In addition, medium-size GA atrophy displayed the most significant changes in inflammation markers.
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Novikova YP, Grigoryan EN. Early Appearance of Aging Signs in the Retinal Pigment Epithelium in Young Albino Rats. Russ J Dev Biol 2020. [DOI: 10.1134/s1062360420060065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Buch J, Hammond B. Photobiomodulation of the Visual System and Human Health. Int J Mol Sci 2020; 21:ijms21218020. [PMID: 33126530 PMCID: PMC7662260 DOI: 10.3390/ijms21218020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/25/2020] [Accepted: 10/27/2020] [Indexed: 12/24/2022] Open
Abstract
Humans express an expansive and detailed response to wavelength differences within the electromagnetic (EM) spectrum. This is most clearly manifest, and most studied, with respect to a relatively small range of electromagnetic radiation that includes the visible wavelengths with abutting ultraviolet and infrared, and mostly with respect to the visual system. Many aspects of our biology, however, respond to wavelength differences over a wide range of the EM spectrum. Further, humans are now exposed to a variety of modern lighting situations that has, effectively, increased our exposure to wavelengths that were once likely minimal (e.g., “blue” light from devices at night). This paper reviews some of those biological effects with a focus on visual function and to a lesser extent, other body systems.
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Affiliation(s)
- John Buch
- Johnson & Johnson Vision, Research & Development, Jacksonville, FL 32256, USA
- Correspondence: ; Tel.: +1-904-443-1707
| | - Billy Hammond
- Department of Psychology, University of Georgia, Athens, GA 30602, USA;
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The Effect of Antioxidants on Photoreactivity and Phototoxic Potential of RPE Melanolipofuscin Granules from Human Donors of Different Age. Antioxidants (Basel) 2020; 9:antiox9111044. [PMID: 33114498 PMCID: PMC7693403 DOI: 10.3390/antiox9111044] [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: 08/28/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 11/17/2022] Open
Abstract
One of the most prominent age-related changes of retinal pigment epithelium (RPE) is the accumulation of melanolipofuscin granules, which could contribute to oxidative stress in the retina. The purpose of this study was to determine the ability of melanolipofuscin granules from younger and older donors to photogenerate reactive oxygen species, and to examine if natural antioxidants could modify the phototoxic potential of this age pigment. Electron paramagnetic resonance (EPR) oximetry, EPR-spin trapping, and time-resolved detection of near-infrared phosphorescence were employed for measuring photogeneration of superoxide anion and singlet oxygen by melanolipofuscin isolated from younger and older human donors. Phototoxicity mediated by internalized melanolipofuscin granules with and without supplementation with zeaxanthin and α-tocopherol was analyzed in ARPE-19 cells by determining cell survival, oxidation of cellular proteins, organization of the cell cytoskeleton, and the cell specific phagocytic activity. Supplementation with antioxidants reduced aerobic photoreactivity and phototoxicity of melanolipofuscin granules. The effect was particularly noticeable for melanolipofuscin mediated inhibition of the cell phagocytic activity. Antioxidants decreased the extent of melanolipofuscin-dependent oxidation of cellular proteins and disruption of the cell cytoskeleton. Although melanolipofuscin might be involved in chronic phototoxicity of the aging RPE, natural antioxidants could partially ameliorate these harmful effects.
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Xu A, Chen C. Clinical application of ultra-widefield fundus autofluorescence. Int Ophthalmol 2020; 41:727-741. [PMID: 33040254 DOI: 10.1007/s10792-020-01609-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 10/01/2020] [Indexed: 11/24/2022]
Abstract
PURPOSE To review the basic principles of ultra-widefield fundus autofluorescence (UWF-FAF) and discuss its clinical application for a variety of retinal and choroidal disorders. METHODS A systematic review of the PubMed database was performed using the search terms "ultra-widefield," "autofluorescence," "retinal disease" and "choroidal disease." RESULTS UWF-FAF imaging is a recently developed noninvasive retinal imaging modality with a wide imaging range that can locate peripheral fundus lesions that traditional fundus autofluorescence cannot. Multiple commercially available ultra-widefield imaging systems, including Heidelberg Spectralis and Optomap Ultra-Widefield systems, are available to the clinician. Imaging by UWF-FAF is more comprehensive; it can reflect the content and distribution of the predominant ocular fluorophore in retinal pigment epithelial cells and evaluate the metabolic status of RPE of various retinal and choroidal disorders. CONCLUSION UWF-FAF can detect abnormalities that traditional fundus autofluorescence cannot; therefore, it can be used to better elucidate disease pathogenesis, analyze genotype-phenotype correlations, diagnose and monitor disease.
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Affiliation(s)
- Amin Xu
- Department of Ophthalmology of Renmin Hospital of Wuhan University, No238, Jiefang Road, Wuhan, 430060, Hubei, China
| | - Changzheng Chen
- Department of Ophthalmology of Renmin Hospital of Wuhan University, No238, Jiefang Road, Wuhan, 430060, Hubei, China.
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Deng Y, Zhang Q, Li Y, Wang L, Yang S, Chen X, Gan C, He F, Ye T, Yin W. Pectolinarigenin inhibits cell viability, migration and invasion and induces apoptosis via a ROS-mitochondrial apoptotic pathway in melanoma cells. Oncol Lett 2020; 20:116. [PMID: 32863929 PMCID: PMC7448562 DOI: 10.3892/ol.2020.11977] [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: 09/16/2019] [Accepted: 05/13/2020] [Indexed: 02/05/2023] Open
Abstract
Pectolinarigenin a plant secondary metabolite that has various biological effects, including the inhibition of melanogenesis and tumor growth. Melanoma has a high degree of malignancy, with rapid metastasis and severe drug resistance, explaining the need for new candidate drugs that inhibit tumor growth and metastasis. However, the pharmacological action and mechanism of pectolinarigenin on the growth and metastasis of melanoma remain elusive. Thus, the present study aimed to investigate the role of pectolinarigenin in melanoma cell proliferation, apoptosis, migration and invasion. Apoptotic and metastasis-associated proteins were analyzed using western blotting. The results demonstrated that pectolinarigenin treatment resulted in growth inhibition and apoptosis induction in melanoma cells, arising from the loss of mitochondrial transmembrane potential, reactive oxygen species and the altered expression of apoptosis-associated proteins. In addition, wound-healing and Transwell assays demonstrated the potential of pectolinarigenin to impair the migration and invasion of melanoma cells in accordance with the changes in the expression of the associated proteins. Therefore, the results of the present study suggested that pectolinarigenin may serve a pivotal role in promoting melanoma cell apoptosis and reducing metastasis, and may thus be a promising potential candidate for an anti-melanoma treatment strategy.
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Affiliation(s)
- Yuanle Deng
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, Sichuan 610064, P.R China
| | - Qianyu Zhang
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, Sichuan 610064, P.R China
| | - Yali Li
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, Sichuan 610064, P.R China
| | - Liqun Wang
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, Sichuan 610064, P.R China
| | - Shuping Yang
- State Key of Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610064, P.R China
| | - Xiaotong Chen
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, Sichuan 610064, P.R China
| | - Cailin Gan
- State Key of Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610064, P.R China
| | - Fang He
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, Sichuan 610064, P.R China
| | - Tinghong Ye
- State Key of Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610064, P.R China
| | - Wenya Yin
- Department of Nutrition, Food Safety and Toxicology, West China School of Public Health and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, Sichuan 610064, P.R China
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Shankar N, Guimarães AO, Napoli E, Giulivi C. Forensic determination of hair deposition time in crime scenes using electron paramagnetic resonance. J Forensic Sci 2020; 66:72-82. [PMID: 32986869 DOI: 10.1111/1556-4029.14570] [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: 06/23/2020] [Revised: 08/06/2020] [Accepted: 08/18/2020] [Indexed: 11/28/2022]
Abstract
Several types of biological samples, including hair strands, are found at crime scenes. Apart from the identification of the value and the contributor of the probative evidence, it is important to prove that the time of shedding of hair belonging to a suspect or victim matches the crime window. To this end, to estimate the ex vivo aging of hair, we evaluated time-dependent changes in melanin-derived free radicals in blond, brown, and black hairs by using electron paramagnetic resonance spectroscopy (EPR). Hair strands aged under controlled conditions (humidity 40%, temperature 20-22°C, indirect light, with 12/12 hour of light/darkness cycles) showed a time-dependent decay of melanin-derived radicals. The half-life of eumelanin-derived radicals in hair under our experimental settings was estimated at 22 ± 2 days whereas that of pheomelanin was about 2 days suggesting better stabilization of unpaired electrons by eumelanin. Taken together, this study provides a reference for future forensic studies on determination of degradation of shed hair in a crime scene by following eumelanin radicals by utilizing the non-invasive, non-destructive, and highly specific EPR technique.
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Affiliation(s)
- Nikhita Shankar
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
| | - André O Guimarães
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA.,Laboratório de Ciências Físicas, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, RJ, Brazil
| | - Eleonora Napoli
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
| | - Cecilia Giulivi
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA.,MIND Institute, University of California Davis Medical Center, Sacramento, CA, USA
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Olchawa MM, Szewczyk GM, Zadlo AC, Krzysztynska-Kuleta OI, Sarna TJ. The effect of aging and antioxidants on photoreactivity and phototoxicity of human melanosomes: An in vitro study. Pigment Cell Melanoma Res 2020; 34:670-682. [PMID: 32702137 DOI: 10.1111/pcmr.12914] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/19/2020] [Accepted: 07/07/2020] [Indexed: 01/08/2023]
Abstract
Aging may significantly modify antioxidant and photoprotective properties of melanin in retinal pigment epithelium (RPE). Here, photoreactivity of melanosomes (MS), isolated from younger and older human donors with and without added zeaxanthin and α-tocopherol, was analyzed by electron paramagnetic resonance oximetry, time-resolved singlet oxygen phosphorescence, and protein oxidation assay. The phototoxic potential of ingested melanosomes was examined in ARPE-19 cells exposed to blue light. Phagocytosis of FITC-labeled photoreceptor outer segments (POS) isolated from bovine retinas was determined by flow cytometry. Irradiation of cells fed MS induced significant inhibition of the specific phagocytosis with the effect being stronger for melanosomes from older than from younger human cohorts, and enrichment of the melanosomes with antioxidants reduced the inhibitory effect. Cellular protein photooxidation was more pronounced in samples containing older melanosomes, and it was diminished by antioxidants. This study suggests that blue light irradiated RPE melanosomes could induce substantial inhibition of the key function of the cells-their specific phagocytosis. The data indicate that while photoreactivity of MS and their phototoxic potential increase with age, they could be reduced by selected natural antioxidants.
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Affiliation(s)
- Magdalena M Olchawa
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Grzegorz M Szewczyk
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Andrzej C Zadlo
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Olga I Krzysztynska-Kuleta
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Tadeusz J Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
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42
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Hu DN, Yao S, Iacob CE, Giovinazzo J, Rosen RB, Grossniklaus HE, Sassoon J. Quantitative Study of Human Scleral Melanocytes and Their Topographical Distribution. Curr Eye Res 2020; 45:1563-1571. [PMID: 32397839 DOI: 10.1080/02713683.2020.1767789] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
PURPOSE While fibroblasts constitute the main cell component of the sclera, the purpose of the present study was to investigate the cell densities of melanocytes at different regions of the sclera, and to compare them with associated scleral fibroblast densities in human donor eye sections. METHODS . Paraffin-embedded sections of sclera from 21 human eyes were stained with hematoxylin-eosin (H&E) and immunohistochemical staining (S-100/AEC). Scleral melanocyte and fibroblast numbers were counted in different regions of the sclera. The relationship between the melanocyte density and iris pigmentation was also analyzed. RESULTS . Melanocytes were found in the posterior region of the sclera, especially around the vessels and nerves in emmissarial canals, whereas no or rare melanocytes were found in equatorial and anterior regions. In H&E sections, melanocyte densities in eyes with light-colored irides were significantly less than in eyes with medium or dark-colored irides (P < .05). In S-100-stained sections, more melanocytes could be detected than those in the H&E sections in light-colored eyes (P < .05), but not in medium or dark-colored eyes (P > .05). The numbers of scleral fibroblasts were relatively stable in different regions. In the posterior scleral region, the numbers of fibroblasts were slightly higher than the number of melanocytes, however, this differences were not statistically significant (P > .05). CONCLUSION . Notable numbers of melanocytes were present in the posterior sclera suggesting that these cells may play a role in ocular physiology and in the pathogenesis of various disorders of the sclera.
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Affiliation(s)
- Dan-Ning Hu
- Department of Pathology, New York Eye and Ear Infirmary of Mount Sinai , New York, NY, USA.,Department of Ophthalmology, Icahn School of Medicine at Mount Sinai , New York, NY, USA
| | - Shen Yao
- Department of Medicine, Icahn School of Medicine at Mount Sinai , New York, NY, USA
| | - Codrin E Iacob
- Department of Pathology, New York Eye and Ear Infirmary of Mount Sinai , New York, NY, USA.,Department of Pathology, Icahn School of Medicine at Mount Sinai , New York, NY, USA
| | - Jerome Giovinazzo
- Department of Pathology, New York Eye and Ear Infirmary of Mount Sinai , New York, NY, USA
| | - Richard B Rosen
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai , New York, NY, USA.,Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai , New York, NY, USA
| | | | - Jodi Sassoon
- Department of Pathology, New York Eye and Ear Infirmary of Mount Sinai , New York, NY, USA.,Department of Pathology, Icahn School of Medicine at Mount Sinai , New York, NY, USA
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COLORADO AGE-RELATED MACULAR DEGENERATION REGISTRY: Design and Clinical Risk Factors of the Cohort. Retina 2020; 39:656-663. [PMID: 29283981 DOI: 10.1097/iae.0000000000002023] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
PURPOSE To study new and existing risk factors related to age-related macular degeneration (AMD) phenotypes in a Colorado cohort. METHODS Age-related macular degeneration was categorized into early, intermediate, or advanced forms. Controls (n = 180) were patients with cataract and no AMD. Demographic and clinical data were gathered by patient interview and verified by chart review. Image data were reviewed by vitreoretinal specialists. Statistical analysis included univariable and multivariate logistic regression analysis (P < 0.05). RESULTS Among the 456 patients with AMD, 157 (34.4%), 80 (17.6%), and 219 (48.0%) had the early/intermediate, geographic atrophy, and neovascular forms of the disease, respectively. Adjusted for age, African-American race was associated with a reduced risk of early/intermediate (adjusted odds ratio [AOR] = 0.08, confidence interval [CI] = 0.01-0.67) and neovascular AMD (AOR = 0.15, CI = 0.03-0.72). A family history of AMD was a risk factor for early/intermediate (AOR = 4.08, CI = 2.30-7.25), geographic atrophy (AOR = 8.62, CI = 3.77-19.7), and neovascular AMD (AOR = 3.76, CI = 2.16-6.56). A history of asthma was related to the early/intermediate form of AMD (AOR = 2.34, CI = 1.22-4.46). CONCLUSION Studying AMD in specific populations may reveal novel risk factors such as our finding of a relationship between asthma history and AMD.
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Żądto A, Ito S, Sarna M, Wakamatsu K, Mokrzyński K, Sarna T. The role of hydrogen peroxide and singlet oxygen in the photodegradation of melanin. Photochem Photobiol Sci 2020; 19:654-667. [PMID: 32307506 DOI: 10.1039/c9pp00481e] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
When aging, melanin in human retinal pigment epithelium (RPE) undergoes oxidative modifications, which increase its photoreactivity and reduce its antioxidant capacity, elevating the risk of chronic phototoxicity to the retina. The aim of this research was to examine the effect of iron on the degradation of melanin induced by hydrogen peroxide and light, and to elucidate the role of hydrogen peroxide and singlet oxygen in the photodegradation of melanin. A water-soluble synthetic model of eumelanin with and without iron ions was treated either with exogenous hydrogen peroxide or with intense violet light. Oxidative modifications of melanin were analyzed by electron paramagnetic resonance (EPR) spectroscopy, absorption spectrophotometry, dynamic light scattering (DLS) and by chemical analysis of melanin subunits. The results showed that although iron strongly accelerated melanin degradation induced by hydrogen peroxide, it had very little influence on the rate of photodegradation of melanin. On the other hand, the photodegradation of melanin was partly inhibited by NaN3. The determination of hydrogen peroxide together with oxygen uptake indicates that irradiated melanin generates similar amounts of singlet oxygen and hydrogen peroxide. Analysis of melanin samples exhibiting comparable reduction of their EPR signal revealed that the loss of the representative melanin subunits was much higher in irradiated samples than in those treated with hydrogen peroxide in the dark. In conclusion, hydrogen peroxide, formed during the aerobic photolysis of melanin, is not responsible for the accompanying oxidative modifications of melanin. On the other hand, singlet oxygen can be considered as a key oxidizing agent involved in the photodegradation of melanin.
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Affiliation(s)
- Andrzej Żądto
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.
| | - Shosuke Ito
- Department of Chemistry, Fujita Health University School of Medical Sciences, Toyoake, Japan
| | - Michał Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Kazumasa Wakamatsu
- Department of Chemistry, Fujita Health University School of Medical Sciences, Toyoake, Japan
| | - Krystian Mokrzyński
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Tadeusz Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
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Seleem AA. Induction of hyperpigmentation and heat shock protein 70 response to the toxicity of methomyl insecticide during the organ development of the Arabian toad, Bufo arabicus (Heyden,1827). J Histotechnol 2019; 42:104-115. [PMID: 31492089 DOI: 10.1080/01478885.2019.1619653] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Methomyl (MET) is a carbamate insecticide which is used as a substitute for organophosphorus compounds to protect crops against insects. The present study aims to evaluate the cytoprotection response of pigment cells and heat shock protein 70 (HSP70) after exposure to MET during the tadpole developmental stages of the Arabian toad, Bufo arabicus. Three developmental larval stages of the toad were selected and divided into two groups; Control and MET-exposed (MET-EX) tadpoles (10ppm). MET-EX tadpoles showed an increased number of pigment cells in the liver, kidney, anterior eye chamber, and skin tissues as compared to the control. The glycogen content in the developing liver and muscles (myotomes) of MET-EX tadpoles was decreased as compared to the control. In the MET-EX tadpoles, immunohistochemical staining showed an increase of HSP70 expression in the liver hepatocytes, the nucleated red blood cells (nRBC) in kidney glomeruli, the iridocorneal angle of anterior eye chamber, and the skin as compared to the control. The current study concluded that pigment cells and HSP70 represented a cytoprotecting response against MET insecticide during the organ development of B. arabicas tadpoles. Therefore, MET use should be regularly monitored in the environment to protect animals and human from exposure to this insecticide.
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Affiliation(s)
- Amin Abdou Seleem
- Zoology Department, Faculty of Science, Sohag University , Sohag , Egypt.,Biology Department, Faculty of Science and Arts, Al-Ula, Taibah University , Medina , Kingdom of Saudi Arabia
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Tao JX, Zhou WC, Zhu XG. Mitochondria as Potential Targets and Initiators of the Blue Light Hazard to the Retina. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:6435364. [PMID: 31531186 PMCID: PMC6721470 DOI: 10.1155/2019/6435364] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 06/18/2019] [Accepted: 07/25/2019] [Indexed: 12/20/2022]
Abstract
Commercially available white light-emitting diodes (LEDs) have an intense emission in the range of blue light, which has raised a range of public concerns about their potential risks as retinal hazards. Distinct from other visible light components, blue light is characterized by short wavelength, high energy, and strong penetration that can reach the retina with relatively little loss in damage potential. Mitochondria are abundant in retinal tissues, giving them relatively high access to blue light, and chromophores, which are enriched in the retina, have many mitochondria able to absorb blue light and induce photochemical effects. Therefore, excessive exposure of the retina to blue light tends to cause ROS accumulation and oxidative stress, which affect the structure and function of the retinal mitochondria and trigger mitochondria-involved death signaling pathways. In this review, we highlight the essential roles of mitochondria in blue light-induced photochemical damage and programmed cell death in the retina, indicate directions for future research and preventive targets in terms of the blue light hazard to the retina, and suggest applying LED devices in a rational way to prevent the blue light hazard.
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Affiliation(s)
- Jin-Xin Tao
- Department of Neurosurgery, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, China
- Department of Clinical Medicine, The Second Clinical Medical College, Nanchang University, Nanchang 330006, China
| | - Wen-Chuan Zhou
- Department of Neurosurgery, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, China
- Department of Clinical Medicine, The Second Clinical Medical College, Nanchang University, Nanchang 330006, China
| | - Xin-Gen Zhu
- Department of Neurosurgery, The Second Affiliated Hospital of Nanchang University, Nanchang 330006, China
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Tham HL, Linder KE, Olivry T. Autoimmune diseases affecting skin melanocytes in dogs, cats and horses: vitiligo and the uveodermatological syndrome: a comprehensive review. BMC Vet Res 2019; 15:251. [PMID: 31324191 PMCID: PMC6639964 DOI: 10.1186/s12917-019-2003-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/12/2019] [Indexed: 02/07/2023] Open
Abstract
Autoimmune dermatoses targeting melanocytes have gained attention in human medicine due to their progressive nature and the social impact suffered by affected individuals. In veterinary medicine, vitiligo and the uveodermatological syndrome are the two autoimmune diseases that are known to affect skin melanocytes.In the first part of this article, we will review the signalment, clinical signs, histopathology and the treatment outcome of vitiligo in dogs, cats and horses; where pertinent, we compare the animal diseases to their human homologue. In a similar fashion, the information on the uveodermatological syndrome in dogs is reviewed and, where relevant, it is compared to the Vogt-Koyanagi-Harada (VKH) syndrome in humans.Canine, feline and equine vitiligo have many features that mirror their human counterparts. The most effective treatment and outcome of vitiligo in animals remain unclear. The canine uveodermatological syndrome resembles the incomplete VKH variant in humans; for affected individuals, an immediate diagnosis and aggressive treatment are crucial to prevent the development of blindness.
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Affiliation(s)
- Heng L. Tham
- Department of Small Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA USA
| | - Keith E. Linder
- Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, NC USA
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC USA
| | - Thierry Olivry
- Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, NC USA
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC USA
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van der Kooij MK, Speetjens FM, van der Burg SH, Kapiteijn E. Uveal Versus Cutaneous Melanoma; Same Origin, Very Distinct Tumor Types. Cancers (Basel) 2019; 11:E845. [PMID: 31248118 PMCID: PMC6627906 DOI: 10.3390/cancers11060845] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/16/2019] [Accepted: 06/17/2019] [Indexed: 02/06/2023] Open
Abstract
Here, we critically evaluated the knowledge on cutaneous melanoma (CM) and uveal melanoma (UM). Both cancer types derive from melanocytes that share the same embryonic origin and display the same cellular function. Despite their common origin, both CM and UM display extreme differences in their genetic alterations and biological behavior. We discuss the differences in genetic alterations, metastatic routes, tumor biology, and tumor-host interactions in the context of their clinical responses to targeted- and immunotherapy.
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Affiliation(s)
- Monique K van der Kooij
- Department of Medical Oncology, Oncode Institute, Leiden University Medical Center, Albinusdreef 2, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
| | - Frank M Speetjens
- Department of Medical Oncology, Leiden University Medical Center, Albinusdreef 2, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
| | - Sjoerd H van der Burg
- Department of Medical Oncology, Oncode Institute, Leiden University Medical Center, Albinusdreef 2, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
| | - Ellen Kapiteijn
- Department of Medical Oncology, Leiden University Medical Center, Albinusdreef 2, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
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Meleppat RK, Zhang P, Ju MJ, Manna SK, Jian Y, Pugh EN, Zawadzki RJ. Directional optical coherence tomography reveals melanin concentration-dependent scattering properties of retinal pigment epithelium. JOURNAL OF BIOMEDICAL OPTICS 2019; 24:1-10. [PMID: 31254332 PMCID: PMC6977406 DOI: 10.1117/1.jbo.24.6.066011] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 05/30/2019] [Indexed: 05/18/2023]
Abstract
Optical coherence tomography (OCT) is a powerful tool in ophthalmology that provides in vivo morphology of the retinal layers and their light scattering properties. The directional (angular) reflectivity of the retinal layers was investigated with focus on the scattering from retinal pigment epithelium (RPE). The directional scattering of the RPE was studied in three mice strains with three distinct melanin concentrations: albino (BALB/c), agouti (129S1/SvlmJ), and strongly pigmented (C57BL/6J). The backscattering signal strength was measured with a directional OCT system in which the pupil entry position of the narrow OCT beam can be varied across the dilated pupil of the eyes of the mice. The directional reflectivity of other retinal melanin-free layers, including the internal and external limiting membranes, and Bruch's membrane (albinos) were also measured and compared between the strains. The intensity of light backscattered from these layers was found highly sensitive to the angle of illumination, whereas the inner/outer segment (IS/OS) junctions showed a reduced sensitivity. The reflections from the RPE are largely insensitive in highly pigmented mice. The differences in directional scattering between strains shows that directionality decreases with an increase in melanin concentrations in RPE, suggesting increasing contribution of Mie scattering by melanosomes.
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Affiliation(s)
- Ratheesh K. Meleppat
- University of California Davis, UC Davis Eyepod, Department of Cell Biology and Human Anatomy, Davis, California, United States
| | - Pengfei Zhang
- University of California Davis, UC Davis Eyepod, Department of Cell Biology and Human Anatomy, Davis, California, United States
| | - Myeong Jin Ju
- Simon Fraser University, School of Engineering Science, Burnaby, British Columbia, Canada
| | - Suman K. Manna
- University of California Davis, UC Davis Eyepod, Department of Cell Biology and Human Anatomy, Davis, California, United States
| | - Yifan Jian
- Oregon Science and Health University, Casey Eye Institute, Portland, Oregon, United States
| | - Edward N. Pugh
- University of California Davis, UC Davis Eyepod, Department of Cell Biology and Human Anatomy, Davis, California, United States
| | - Robert J. Zawadzki
- University of California Davis, UC Davis Eyepod, Department of Cell Biology and Human Anatomy, Davis, California, United States
- University of California Davis, UC Davis Eye Center, Department of Ophthalmology and Vision Science, Sacramento, California, United States
- Address all correspondence to Robert J. Zawadzki, E-mail:
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50
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Granger CE, Yang Q, Song H, Saito K, Nozato K, Latchney LR, Leonard BT, Chung MM, Williams DR, Rossi EA. Human Retinal Pigment Epithelium: In Vivo Cell Morphometry, Multispectral Autofluorescence, and Relationship to Cone Mosaic. Invest Ophthalmol Vis Sci 2019; 59:5705-5716. [PMID: 30513531 PMCID: PMC6280915 DOI: 10.1167/iovs.18-24677] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Purpose To characterize in vivo morphometry and multispectral autofluorescence of the retinal pigment epithelial (RPE) cell mosaic and its relationship to cone cell topography across the macula. Methods RPE cell morphometrics were computed in regularly spaced regions of interest (ROIs) from contiguous short-wavelength autofluorescence (SWAF) and photoreceptor reflectance images collected across the macula in one eye of 10 normal participants (23–65 years) by using adaptive optics scanning light ophthalmoscopy (AOSLO). Infrared autofluorescence (IRAF) images of the RPE were collected with AOSLO in seven normal participants (22–65 years), with participant overlap, and compared to SWAF quantitatively and qualitatively. Results RPE cell statistics could be analyzed in 84% of SWAF ROIs. RPE cell density consistently decreased with eccentricity from the fovea (participant mean ± SD: 6026 ± 1590 cells/mm2 at fovea; 4552 ± 1370 cells/mm2 and 3757 ± 1290 cells/mm2 at 3.5 mm temporally and nasally, respectively). Mean cone-to-RPE cell ratio decreased rapidly from 16.6 at the foveal center to <5 by 1 mm. IRAF revealed cells in six of seven participants, in agreement with SWAF RPE cell size and location. Differences in cell fluorescent structure, contrast, and visibility beneath vasculature were observed between modalities. Conclusions Improvements in AOSLO autofluorescence imaging permit efficient visualization of RPE cells with safe light exposures, allowing individual characterization of RPE cell morphometry that is variable between participants. The normative dataset and analysis of RPE cell IRAF and SWAF herein are essential for understanding microscopic characteristics of cell fluorescence and may assist in interpreting disease progression in RPE cells.
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Affiliation(s)
- Charles E Granger
- Center for Visual Science, University of Rochester, Rochester, New York, United States.,The Institute of Optics, University of Rochester, Rochester, New York, United States
| | - Qiang Yang
- Center for Visual Science, University of Rochester, Rochester, New York, United States
| | - Hongxin Song
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Key Laboratory of Ophthalmology and Visual Sciences, National Engineering Research Center for Ophthalmic Equipment, Beijing, China
| | - Kenichi Saito
- Canon U.S.A., Inc., Melville, New York, United States
| | - Koji Nozato
- Canon U.S.A., Inc., Melville, New York, United States
| | - Lisa R Latchney
- Flaum Eye Institute, University of Rochester Medical Center, Rochester, New York, United States
| | - Bianca T Leonard
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Mina M Chung
- Center for Visual Science, University of Rochester, Rochester, New York, United States.,Flaum Eye Institute, University of Rochester Medical Center, Rochester, New York, United States
| | - David R Williams
- Center for Visual Science, University of Rochester, Rochester, New York, United States.,The Institute of Optics, University of Rochester, Rochester, New York, United States
| | - Ethan A Rossi
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
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