1
|
Ohishi K, Hosono K, Obana A, Noda A, Hiramitsu T, Hotta Y, Minoshima S. Identification of susceptibility loci for light-induced visual impairment in rats. Exp Eye Res 2021; 210:108688. [PMID: 34237304 DOI: 10.1016/j.exer.2021.108688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/14/2021] [Accepted: 06/29/2021] [Indexed: 12/01/2022]
Abstract
Bright light exposure in animals results in the selective degeneration of the outer retina, known as "retinal photic injury" (RPI). The susceptibility to RPI differs among rat strains. WKY rats display susceptibility to RPI with extensive retinal degeneration observed in the sagittal eye specimen, whereas LEW strain rats are resistant to it, showing only slight or no degeneration. In the present study, we first established an ethological screening method using the Morris water maze to discern differential susceptibility among the living rats. WKY and LEW were crossed to produce the first filial generation (F1) offspring. Maze-trained individuals were exposed to bright, white light. The screening test results demonstrated that the susceptibility to light-induced visual impairment in rats is a dominant Mendelian susceptibility trait, as F1 rats were susceptible to visual impairment like WKY rats. Therefore, F1 rats were backcrossed with recessive LEW to produce the first backcross offspring (BC1). Subsequent recurrent backcrossing while selecting for the susceptibility, indicated a segregation ratio of ca. 24% in BC1 and BC2 generations, indicating the involvement of two or more genes in the susceptibility. Further, microsatellite analysis of BC1-to-BC4 individuals using microsatellite markers mapped two susceptibility loci on chromosome segments 5q36 and 19q11-q12, named RPI susceptibility (Rpi)1 and Rpi2, respectively. This study provides an insight into mechanisms underlying differential susceptibility, which could help decipher the mechanism underlying the onset/progression of human age-related macular degeneration.
Collapse
Affiliation(s)
- Kentaro Ohishi
- Department of Photomedical Genomics, Institute for Medical Photonics Research, Preeminent Medical Photonics Education & Research Center, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan.
| | - Katsuhiro Hosono
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - Akira Obana
- Hamamatsu BioPhotonics Innovation Chair, Institute for Medical Photonics Research, Preeminent Medical Photonics Education and Research Center, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan; Department of Ophthalmology, Seirei Hamamatsu General Hospital, 2-12-12 Sumiyoshi, Naka-ku, Hamamatsu, 430-8558, Japan
| | - Akio Noda
- Department of Integrated Human Sciences (Mathematics), Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - Tadahisa Hiramitsu
- Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - Yoshihiro Hotta
- Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| | - Shinsei Minoshima
- Department of Photomedical Genomics, Institute for Medical Photonics Research, Preeminent Medical Photonics Education & Research Center, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, 431-3192, Japan
| |
Collapse
|
2
|
Schuierer MM, Langmann T. Molecular diagnosis of ATP-binding cassette transporter-related diseases. Expert Rev Mol Diagn 2014; 5:755-67. [PMID: 16149878 DOI: 10.1586/14737159.5.5.755] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ATP-binding cassette (ABC) transporters are involved in a variety of physiologic processes such as xenobiotic defense, lipid metabolism, ion homeostasis and immune functions. A large number of ABC proteins have been causatively linked to rare and common human genetic diseases including familial high-density lipoprotein deficiency, retinopathies, cystic fibrosis, diabetes and cardiomyopathies. Furthermore, genetic variations in ABC transporter genes and dysregulated expression patterns of these molecules significantly contribute to drug resistance in human cancer cells and alter the pharmacokinetic properties of a variety of drugs. In order to analyze DNA sequence alterations or define disease-associated mRNA expression patterns of the complete ABC transporter superfamily, novel high-throughput molecular methods such as quantitative real-time PCR and DNA microarray analysis are emerging. The aim of this review is to provide an overview and to present some examples of human ABC transporters involved in monogenic diseases, cancer and pharmacogenetics. Methodologic aspects of molecular diagnostics applied to analyze genetic variations, mRNA and protein expression levels and functional characteristics of ABC transporters are discussed.
Collapse
Affiliation(s)
- Marion M Schuierer
- University of Regensburg, Institute of Pathology, Franz-Josef-Strauss Allee 11, D-93053, Germany.
| | | |
Collapse
|
3
|
Affiliation(s)
| | | | - Krzysztof Palczewski
- Department of Pharmacology, School of Medicine, Case
Western Reserve University, 2109 Adelbert Road, Cleveland, Ohio 44106-4965,
United States
| |
Collapse
|
4
|
Hjelmeland LM. Dark matters in AMD genetics: epigenetics and stochasticity. Invest Ophthalmol Vis Sci 2011; 52:1622-31. [PMID: 21429863 DOI: 10.1167/iovs.10-6765] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Affiliation(s)
- Leonard M Hjelmeland
- Department of Ophthalmology and Vision Science, School of Medicine, University of California, Davis, California, USA.
| |
Collapse
|
5
|
Rattner A, Nathans J. Macular degeneration: recent advances and therapeutic opportunities. Nat Rev Neurosci 2006; 7:860-72. [PMID: 17033682 DOI: 10.1038/nrn2007] [Citation(s) in RCA: 155] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The central retina mediates high acuity vision, and its progressive dysfunction due to macular degeneration is the leading cause of visual disability among adults in industrialized societies. Here, we summarize recent progress in understanding the pathophysiology of macular degeneration and the implications of this new knowledge for treatment and prevention. The past decade has witnessed remarkable advances in this field, including the development of new, non-invasive retinal imaging technologies, the development of animal models for macular disease, and the isolation of many of the genes responsible for both early- and late-onset macular diseases. These advances have set the stage for the development of effective mechanism-based therapies.
Collapse
Affiliation(s)
- Amir Rattner
- Department of Molecular Biology and Genetics, Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | | |
Collapse
|
6
|
Rózanowska M, Sarna T. Light-induced damage to the retina: role of rhodopsin chromophore revisited. Photochem Photobiol 2006; 81:1305-30. [PMID: 16120006 DOI: 10.1562/2004-11-13-ir-371] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The presence of the regenerable visual pigment rhodopsin has been shown to be primarily responsible for the acute photodamage to the retina. The photoexcitation of rhodopsin leads to isomerization of its chromophore 11-cis-retinal to all-trans-retinal (ATR). ATR is a potent photosensitizer and its role in mediating photodamage has been suspected for over two decades. However, there was lack of experimental evidence that free ATR exists in the retina in sufficient concentrations to impose a risk of photosensitized damage. Identification in the retina of a retinal dimer and a pyridinium bisretinoid, so called A2E, and determination of its biosynthetic pathway indicate that substantial amounts of ATR do accumulate in the retina. Both light damage and A2E accumulation are facilitated under conditions where efficient retinoid cycle operates. Efficient retinoid cycle leads to rapid regeneration of rhodopsin, which may result in ATR release from the opsin "exit site" before its enzymatic reduction to all-trans-retinol. Here we discuss photodamage to the retina where ATR could play a role as the main toxic and/or phototoxic agent. Moreover, we discuss secondary products of (photo)toxic properties accumulating within retinal lipofuscin as a result of ATR accumulation.
Collapse
|
7
|
Thomas BB, Seiler MJ, Sadda SR, Aramant RB. Superior colliculus responses to light – preserved by transplantation in a slow degeneration rat model. Exp Eye Res 2004; 79:29-39. [PMID: 15183098 DOI: 10.1016/j.exer.2004.02.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2003] [Accepted: 02/24/2004] [Indexed: 12/01/2022]
Abstract
PURPOSE To determine whether retinal transplantation can preserve visual responses in the superior colliculus (SC) of the S334ter-line-5 rat, a transgenic model for slow photoreceptor degeneration, which is more similar to human retinitis pigmentosa than the fast degeneration line 3 S334ter rat. METHODS Visual responses to a light flash were recorded in the SC. Rats that had received embryonic day (E) 19-20 fetal retinal sheet transplants at the age of 26-30 days were tested at the ages of 200-254 days. Controls were age-matched rats without surgery and with sham surgery. As a baseline, in no-surgery line-5 rats, the temporal pattern of visual sensitivity loss was evaluated electrophysiologically in the SC from 60 days up to one year of age. RESULTS In untreated S334ter-line-5 rats, decline in visual sensitivity in the SC was parallel to the photoreceptor loss. At 109 day of age, a relative scotoma developed in the area of the SC corresponding to the nasal retinal region. At 200-254 days of age, the majority of the SC was devoid of any light-driven responses. In contrast, at this time point, transplanted rats with 'good' retinal grafts with normal lamination had visual responses in the caudal region of the SC, the area corresponding topographically to the transplant location in the retina. In these rats, the various parameters of SC responses such as the latency of the onset of the visual response, the response peak amplitude and the consistency of the visual response were significantly different from the control groups (no-surgery, sham surgery, 'poor' transplants) and were more comparable to normal albino rats, however, with a slightly longer latency (70-90 vs. 30-50 msec). CONCLUSIONS Fetal retinal sheet transplantation showed a long-term rescue effect on visual function in this animal model of slow photoreceptor degeneration.
Collapse
Affiliation(s)
- Biju B Thomas
- Department of Ophthalmology, Doheny Eye Institute, University of Southern California, 1450 San Pablo St, Los Angeles, CA 90033, USA
| | | | | | | |
Collapse
|
8
|
Bonastre J, Le Pen C, Soubrane G, Quentel G. The burden of age-related macular degeneration: results of a cohort study in two French referral centres. PHARMACOECONOMICS 2003; 21:181-190. [PMID: 12558468 DOI: 10.2165/00019053-200321030-00003] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
OBJECTIVE To describe the economic impact of age-related macular degeneration (AMD) and to assess its medical and non-medical costs. DESIGN AND SETTINGS An observational study was carried out in 105 patients in two French centres in a sample of 105 French patients. All consecutive patients, consulting during a 3-week period, were included provided they were 60 years of age or older and they presented an exudative form of AMD with a distant visual acuity in the best eye < or = 20/40. Data collected included clinical items, treatment modalities, medical follow-up, transport costs, impact of AMD on living conditions and welfare payments related to visual impairment. Costs were presented in 2000 values. PERSPECTIVE General payer perspective (Social Security, private health insurance and patient). RESULTS Mean age was 79.3 years and ranged from 62.8-95 years. Average length of disease evolution was 3.5 years. During a 3-month period, patients had a mean of 2.6 visits to the ophthalmologist. Thirty percent of the patients used vascular medications and 72.4% had been previously treated by laser photocoagulation. Only 10% had benefited from visual rehabilitation. Annual AMD cost per patient was 3660.29 euros (EUR) [95% CI: 2881.92-4438.62]. Half of these annual costs were medical costs. Other major cost components were home help costs EUR904.91 [95% CI: 478.88-1330.94] and transport costs for care EUR542.73 [95% CI: 146.31-939.14]. Non-medical costs were significantly higher for patients with more severe disease. CONCLUSIONS The economic argument that costs are higher in patients with the lowest visual acuity emphasises the necessity of early detection and treatment of patients with AMD.
Collapse
|
9
|
Lund RD, Kwan AS, Keegan DJ, Sauvé Y, Coffey PJ, Lawrence JM. Cell transplantation as a treatment for retinal disease. Prog Retin Eye Res 2001; 20:415-49. [PMID: 11390255 DOI: 10.1016/s1350-9462(01)00003-9] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
It has been shown that photoreceptor degeneration can be limited in experimental animals by transplantation of fresh RPE to the subretinal space. There is also evidence that retinal cell transplants can be used to reconstruct retinal circuitry in dystrophic animals. Here we describe and review recent developments that highlight the necessary steps that should be taken prior to embarking on clinical trials in humans.
Collapse
Affiliation(s)
- R D Lund
- Institute of Ophthalmology, Bath Street, EC1V 9EL, London, UK
| | | | | | | | | | | |
Collapse
|
10
|
McBee JK, Palczewski K, Baehr W, Pepperberg DR. Confronting complexity: the interlink of phototransduction and retinoid metabolism in the vertebrate retina. Prog Retin Eye Res 2001; 20:469-529. [PMID: 11390257 DOI: 10.1016/s1350-9462(01)00002-7] [Citation(s) in RCA: 259] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Absorption of light by rhodopsin or cone pigments in photoreceptors triggers photoisomerization of their universal chromophore, 11-cis-retinal, to all-trans-retinal. This photoreaction is the initial step in phototransduction that ultimately leads to the sensation of vision. Currently, a great deal of effort is directed toward elucidating mechanisms that return photoreceptors to the dark-adapted state, and processes that restore rhodopsin and counterbalance the bleaching of rhodopsin. Most notably, enzymatic isomerization of all-trans-retinal to 11-cis-retinal, called the visual cycle (or more properly the retinoid cycle), is required for regeneration of these visual pigments. Regeneration begins in rods and cones when all-trans-retinal is reduced to all-trans-retinol. The process continues in adjacent retinal pigment epithelial cells (RPE), where a complex set of reactions converts all-trans-retinol to 11-cis-retinal. Although remarkable progress has been made over the past decade in understanding the phototransduction cascade, our understanding of the retinoid cycle remains rudimentary. The aim of this review is to summarize recent developments in our current understanding of the retinoid cycle at the molecular level, and to examine the relevance of these reactions to phototransduction.
Collapse
Affiliation(s)
- J K McBee
- Department of Ophthalmology, University of Washington, Seattle, WA 98195, USA
| | | | | | | |
Collapse
|
11
|
Paloma E, Martínez-Mir A, Vilageliu L, Gonzàlez-Duarte R, Balcells S. Spectrum of ABCA4 (ABCR) gene mutations in Spanish patients with autosomal recessive macular dystrophies. Hum Mutat 2001; 17:504-10. [PMID: 11385708 DOI: 10.1002/humu.1133] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The ABCA4 gene has been involved in several forms of inherited macular dystrophy. In order to further characterize the complex genotype-phenotype relationships involving this gene, we have performed a mutation analysis of ABCA4 in 14 Spanish patients comprising eight STGD (Stargardt), four FFM (fundus flavimaculatus), and two CRD (Cone-rod dystrophy) patients. SSCP (single-strand conformation polymorphism) analysis and DNA sequencing of the coding and 5' upstream regions of this gene allowed the identification of 16 putatively pathogenic alterations, nine of which are novel. Most of these were missense changes, and no patient was found to carry two null alleles. Overall, the new data agree with a working model relating the different pathogenic phenotypes to the severity of the mutations. When considering the information presented here together with that of previous reports, a picture of the geographic distribution of three particular mutations emerges. The R212C change has been found in French, Italian, Dutch, German, and Spanish but not in British patients. In the Spanish collection, R212C was found in a CRD patient, indicating that it may be a rather severe change. In contrast, c.2588G>C, a very common mild allele in the Dutch population, is rarely found in Southern Europe. Interestingly, the c.2588G>C mutation has been found in a double mutant allele together with the missense R1055W. Finally, the newly described L1940P was found in two unrelated Spanish patients, and may be a moderate to severe allele.
Collapse
Affiliation(s)
- E Paloma
- Departament de Genètica, Universitat de Barcelona, Barcelona, Spain
| | | | | | | | | |
Collapse
|
12
|
Suter M, Remé C, Grimm C, Wenzel A, Jäättela M, Esser P, Kociok N, Leist M, Richter C. Age-related macular degeneration. The lipofusion component N-retinyl-N-retinylidene ethanolamine detaches proapoptotic proteins from mitochondria and induces apoptosis in mammalian retinal pigment epithelial cells. J Biol Chem 2000; 275:39625-30. [PMID: 11006290 DOI: 10.1074/jbc.m007049200] [Citation(s) in RCA: 251] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
10-20% of individuals over the age of 65 suffer from age-related macular degeneration (AMD), the leading cause of severe visual impairment in humans living in developed countries. The pathogenesis of this complex disease is poorly understood, and no efficient therapy or prevention exists to date. A precondition for AMD appears to be the accumulation of the age pigment lipofuscin in lysosomes of retinal pigment epithelial (RPE) cells. In AMD, these cells seem to die by apoptosis with subsequent death of photoreceptor cells, and light may accelerate the disease process. Intracellular factors leading to cell death are not known. Here we show that the lipophilic cation N-retinyl-N-retinylidene ethanolamine (A2E), a lipofuscin component, induces apoptosis in RPE and other cells at concentrations found in human retina. Apoptosis is accompanied by the appearance of the proapoptotic proteins cytochrome c and apoptosis-inducing factor in the cytoplasm and the nucleus. Biochemical examinations show that A2E specifically targets cytochrome oxidase (COX). With both isolated mitochondria and purified COX, A2E inhibits oxygen consumption synergistically with light. Inhibition is reversed by the addition of cytochrome c or cardiolipin, a negatively charged phospholipid that facilitates the binding of cytochrome c to membranes. Succinate dehydrogenase activity is not altered by A2E. We suggest that A2E can act as a proapoptotic molecule via a mitochondria-related mechanism, possibly through site-specific targeting of this cation to COX. Loss of RPE cell viability through inhibition of mitochondrial function might constitute a pivotal step toward the progressive degeneration of the central retina.
Collapse
Affiliation(s)
- M Suter
- Institute of Biochemistry, Swiss Federal Institute of Technology, Universitätstr. 16, CH-8092 Zurich, Switzerland
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Allikmets R. Simple and complex ABCR: genetic predisposition to retinal disease. Am J Hum Genet 2000; 67:793-9. [PMID: 10970771 PMCID: PMC1287884 DOI: 10.1086/303100] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2000] [Accepted: 08/15/2000] [Indexed: 11/03/2022] Open
Affiliation(s)
- R Allikmets
- Departments of Ophthalmology and Pathology, Columbia University, New York, NY 10032, USA.
| |
Collapse
|
14
|
Maugeri A, Klevering BJ, Rohrschneider K, Blankenagel A, Brunner HG, Deutman AF, Hoyng CB, Cremers FP. Mutations in the ABCA4 (ABCR) gene are the major cause of autosomal recessive cone-rod dystrophy. Am J Hum Genet 2000; 67:960-6. [PMID: 10958761 PMCID: PMC1287897 DOI: 10.1086/303079] [Citation(s) in RCA: 227] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2000] [Accepted: 08/07/2000] [Indexed: 11/03/2022] Open
Abstract
The photoreceptor cell-specific ATP-binding cassette transporter gene (ABCA4; previously denoted "ABCR") is mutated, in most patients, with autosomal recessive (AR) Stargardt disease (STGD1) or fundus flavimaculatus (FFM). In addition, a few cases with AR retinitis pigmentosa (RP) and AR cone-rod dystrophy (CRD) have been found to have ABCA4 mutations. To evaluate the importance of the ABCA4 gene as a cause of AR CRD, we selected 5 patients with AR CRD and 15 patients from Germany and The Netherlands with isolated CRD. Single-strand conformation-polymorphism analysis and sequencing revealed 19 ABCA4 mutations in 13 (65%) of 20 patients. In six patients, mutations were identified in both ABCA4 alleles; in seven patients, mutations were detected in one allele. One complex ABCA4 allele (L541P;A1038V) was found exclusively in German patients with CRD; one patient carried this complex allele homozygously, and five others were compound heterozygous. These findings suggest that mutations in the ABCA4 gene are the major cause of AR CRD. A primary role of the ABCA4 gene in STGD1/FFM and AR CRD, together with the gene's involvement in an as-yet-unknown proportion of cases with AR RP, strengthens the idea that mutations in the ABCA4 gene could be the most frequent cause of inherited retinal dystrophy in humans.
Collapse
Affiliation(s)
- A Maugeri
- Department of Human Genetics, University Medical Centre-Nijmegen, 6500 HB Nijmegen, The Netherlands.
| | | | | | | | | | | | | | | |
Collapse
|