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Kundakci YE, Bilir A, Atay E, Vurmaz A, Firat F, Arikan ES. Protective Effects of Different Doses of Ginsenoside-Rb1 Experimental Cataract Model That in Chick Embryos. Curr Eye Res 2023; 48:817-825. [PMID: 37260421 DOI: 10.1080/02713683.2023.2221415] [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: 03/20/2023] [Revised: 05/04/2023] [Accepted: 05/31/2023] [Indexed: 06/02/2023]
Abstract
PURPOSE There has been increased interest in phytochemical antioxidants to prevent protein damage and aggregate formation in cataract treatment. In this study, the protective effect of different doses of Rb1 (GRb1), one of the ginsenosides of Panax Ginseng, in the experimental cataract model formed in chick embryos was investigated. METHODS Five different experimental groups were formed with 100 SPF fertilized eggs: Control (0.9% NaCl to physiological saline), hydrocortisone hemisuccinate sodium (HC), low dose (HC + L-GRb1 (1 mg/kg)), medium dose (HC+). M-GRb1 (2.5 mg/kg)), and high dose (HC + H-GRb1 (5 mg/kg)). All solutions were given to air sack at 15 days of incubation. On the 17th day, the bulbous oculi of the chick embryos were dissected. Cataract formations of the lenses, glutathione (GSH), malondialdehyde (MDA), total antioxidant (TAS), total oxidant (TOS) levels, Caspase-3 H-score, and TUNEL index were determined. In addition, crystalline alpha A (CRYAA) gene expression was evaluated. RESULTS Cataracts were observed in the control, HC, HC + L-GRb1, HC + M-GRb1, and HC + H-GRb1 groups with a frequency of 0%, 100%, 75%, 56.25%, and 100%, respectively. There were statistically significant differences between the control and HC groups in terms of TAS, TOS, MDA, GSH, Caspase-3 H-score, and TUNEL index (p < .05). When the therapeutic effect of the GRb1 groups was evaluated, the HC group showed significant differences with the HC + L-GRb1 and HC + M-GRb1 groups in almost all parameters (p < .05), while there was no statistical difference with the HC + H-GRb1 group (p > .05). In addition, gene expression levels differed between the groups, although not statistically significant (p > .05). CONCLUSION 1 mg/kg and 2.5 mg/kg GRb1 applications show therapeutic properties on the HC-induced cataract model. This effect is more pronounced at 2.5 mg/kg.
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Affiliation(s)
- Yunus Emre Kundakci
- Department of Physiotherapy and Rehabilitation, Faculty of Health Sciences, Afyonkarahisar Health Sciences University, Afyonkarahisar, Turkey
| | - Abdulkadir Bilir
- Department of Anatomy, Faculty of Medicine, Afyonkarahisar Health Sciences University, Afyonkarahisar, Turkey
| | - Emre Atay
- Department of Anatomy, Faculty of Medicine, Afyonkarahisar Health Sciences University, Afyonkarahisar, Turkey
| | - Ayhan Vurmaz
- Department of Biochemistry, Faculty of Medicine, Afyonkarahisar Health Sciences University, Afyonkarahisar, Turkey
| | - Fatma Firat
- Department of Histology and Embryology, Medicine Faculty, Afyonkarahisar Health Sciences University, Afyonkarahisar, Turkey
| | - Evrim Suna Arikan
- Department of Medical Biology, Faculty of Medicine, Afyonkarahisar Health Sciences University, Afyonkarahisar, Turkey
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Ma X, Nan Y, Huang C, Li X, Yang Y, Jiang W, Ye M, Liu Q, Niu Y, Yuan L. Expression of αA-crystallin (CRYAA) in vivo and in vitro models of age-related cataract and the effect of its silencing on HLEB3 cells. Aging (Albany NY) 2023; 15:204754. [PMID: 37253645 DOI: 10.18632/aging.204754] [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: 03/04/2023] [Accepted: 05/16/2023] [Indexed: 06/01/2023]
Abstract
AIM To investigate the expression of αA-crystallin (CRYAA) in age-related cataract (ARC) models and its role in lens epithelial cells (LECs). METHODS We used Flow cytometry to detect the apoptosis and cell cycle in HLEB3 cells and Real-time fluorescence quantitative polymerase chain reaction to detect the expression of CRYAA mRNA in HLEB3 and in rabbit lens. The expression of CRYAA in HLEB3 cells and rabbit lenses as well as the proteins related to apoptosis and autophagy in transfected cells were detected by western blotting. The lens structure in rabbits was investigated using hematoxylin-eosin staining. Protein thermostability assay was performed to detect the thermal stability of rabbit lens proteins. CCK- 8 assay was used to detect the viability of transfected cells, and the transfection was recorded by fluorescence photography. RESULTS Hydrogen peroxide can promote apoptosis and arrest the cell cycle in HLEB3 cells, and naphthalene can cause cataract formation and damage the structure of the lens in rabbits. Both ARC models can reduce the expression of CRYAA. The expression of CRYAA silencing increased apoptosis and autophagy in HLEB3 cells.
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Affiliation(s)
- Xiaoling Ma
- Ningxia Medical University Key Laboratory of Ningxia Minority Medicine Modernization Ministry of Education, Ningxia Medical University, Yinchuan 750004, Ningxia, China
| | - Yi Nan
- Ningxia Medical University Key Laboratory of Ningxia Minority Medicine Modernization Ministry of Education, Ningxia Medical University, Yinchuan 750004, Ningxia, China
| | - Can Huang
- Ningxia Medical University Key Laboratory of Ningxia Minority Medicine Modernization Ministry of Education, Ningxia Medical University, Yinchuan 750004, Ningxia, China
| | - Xiangyang Li
- School of Traditional Chinese Medicine, Ningxia Medical University, Yinchuan 750004, Ningxia, China
| | - Yifan Yang
- Ningxia Medical University Key Laboratory of Ningxia Minority Medicine Modernization Ministry of Education, Ningxia Medical University, Yinchuan 750004, Ningxia, China
| | - Wenjie Jiang
- Ningxia Medical University Key Laboratory of Ningxia Minority Medicine Modernization Ministry of Education, Ningxia Medical University, Yinchuan 750004, Ningxia, China
| | - Mengyi Ye
- School of Traditional Chinese Medicine, Ningxia Medical University, Yinchuan 750004, Ningxia, China
| | - Qian Liu
- School of Clinical Medicine, Ningxia Medical University, Yinchuan 750004, Ningxia, China
| | - Yang Niu
- Ningxia Medical University Key Laboratory of Ningxia Minority Medicine Modernization Ministry of Education, Ningxia Medical University, Yinchuan 750004, Ningxia, China
- School of Traditional Chinese Medicine, Ningxia Medical University, Yinchuan 750004, Ningxia, China
| | - Ling Yuan
- Ningxia Medical University Key Laboratory of Ningxia Minority Medicine Modernization Ministry of Education, Ningxia Medical University, Yinchuan 750004, Ningxia, China
- School of Pharmacy, Ningxia Medical University, Yinchuan 750004, Ningxia Hui Autonomous Region, China
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Zhao Z, Chen J, Yuan W, Jiang Y, Lu Y. Association between single nucleotide polymorphisms in exon 3 of the alpha-A-crystallin gene and susceptibility to age-related cataract. Ophthalmic Genet 2023; 44:127-132. [PMID: 36380611 DOI: 10.1080/13816810.2022.2092757] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND The mutations in the αA-crystallin (CRYAA) gene may contribute to the development of age-related cataract (ARC). In this study, we searched for single nucleotide polymorphisms (SNP) in exons of CRYAA and investigated the associations between the identified SNPs and the subtypes of ARC. MATERIALS AND METHODS Peripheral venous blood was collected for the extraction of genomic DNA. Three exons of CRYAA were sequenced to detect SNPs. The frequency distributions of alleles and genotypes were compared between the ARC and control groups. RESULTS There were 618 patients with various subtypes of ARC (nuclear cataract [NC], cortical cataract [CC], posterior subcapsular cataract [PSC]). The control group comprised 236 patients. The incidence of early-onset cataract was significantly greater in PSC patients (P = .002 for NC; P = .036 for CC). One SNP was detected in exon 3 of CRYAA (rs76740365 G>A). When the distribution of rs76740365 was compared among the ARC subtypes, only the difference between the PSC group and the control group was statistically significant (allele frequency: P = .000057, OR 2.945; genotype distribution frequency: P = .000458). The heterozygote genotype (GA) carried a significantly greater risk than the homozygous wild-type genotype (GG) by 1.742 times for all types of cataracts and 2.369 times for the PSC subtype. CONCLUSIONS The SNP rs76740365 G>A in exon 3 of the CRYAA gene is associated with greater susceptibility of ARC, particularly the PSC subtype. Individuals carrying the SNP rs76740365 G>A may be more likely to develop PSC at a younger age than other subtypes.
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Affiliation(s)
- Zhennan Zhao
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Jiahui Chen
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Wenyi Yuan
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yongxiang Jiang
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yi Lu
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
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Zhao Z, Sun Y, Fan Q, Jiang Y, Lu Y. Structural and functional analysis of SNP rs76740365 G>A in exon-3 of the alpha A-crystallin gene in lens epithelial cells. Mol Vis 2022; 28:317-330. [PMID: 36338667 PMCID: PMC9603911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 09/28/2022] [Indexed: 11/16/2022] Open
Abstract
Purpose To clarify the effect of a previously identified single nucleotide polymorphism (SNP; rs76740365 G>A) in the exon-3 of the alpha A-crystallin (CRYAA) gene on the properties of CRYAA and to investigate its function in human lens epithelial cells (HLECs). Methods The human recombinant wild-type and mutant CRYAA (E156K) were constructed, and the molecular weight was measured by mass spectrometry. The structural changes induced by E156K mutation were analyzed by UV circular dichroism spectra and intrinsic tryptophan fluorescence and were predicted using Schrödinger software. The chaperone-like ability of wild-type and E156K mutant CRYAA was invested against the heat-induced aggregation of βL-crystallin and the DTT-induced aggregation of insulin. HLECs expressing wild-type and mutated CRYAA were subjected to quantitative PCR (qPCR) and western blot. Cell apoptosis was determined using flow cytometry analysis, and the expression of apoptosis-related proteins were determined using western blot. Results The mass spectrometric detection revealed that E156K mutation had no significant effect on the apparent molecular mass of the CRYAA oligomeric complex. Evaluation of the structures of the CRYAA indicated that E156K mutation did not significantly affect the secondary structures, while causing perturbations of the tertiary structure. The mutant CRYAA displayed an increase in chaperone-like activity, which might be related to the increase of the surface hydrophobicity. We also predicted that E156K mutation would induce a change from negatively charged surface to positively charged, which was the possible reason for the disturbance to the surface hydrophobicity. Transfection studies of HLECs revealed that the E156K mutant induced anti-apoptotic function in HLECs, which was possibly associated with the activation of the p-AKT signal pathway and downregulation of Casepase3. Conclusions Taken together, our results for the first time showed that E156K mutation in CRYAA associated with ARC resulted in enhanced chaperone-like function by inducing its surface hydrophobicity, which was directly related to the activation of its anti-apoptotic function.
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Affiliation(s)
- Zhennan Zhao
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China,Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yang Sun
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China,Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Qi Fan
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China,Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yongxiang Jiang
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China,Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yi Lu
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China,Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
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Shiels A, Hejtmancik JF. Inherited cataracts: Genetic mechanisms and pathways new and old. Exp Eye Res 2021; 209:108662. [PMID: 34126080 PMCID: PMC8595562 DOI: 10.1016/j.exer.2021.108662] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/13/2021] [Accepted: 06/01/2021] [Indexed: 12/15/2022]
Abstract
Cataract(s) is the clinical equivalent of lens opacity and is caused by light scattering either by high molecular weight protein aggregates in lens cells or disruption of the lens microarchitecture itself. Genetic mutations underlying inherited cataract can provide insight into the biological processes and pathways critical for lens homeostasis and transparency, classically including the lens crystallins, connexins, membrane proteins or components, and intermediate filament proteins. More recently, cataract genes have been expanded to include newly identified biological processes such as chaperone or protein degradation components, transcription or growth factors, channels active in the lens circulation, and collagen and extracellular matrix components. Cataracts can be classified by age, and in general congenital cataracts are caused by severe mutations resulting in major damage to lens proteins, while age related cataracts are associated with variants that merely destabilize proteins thereby increasing susceptibility to environmental insults over time. Thus there might be separate pathways to opacity for congenital and age-related cataracts whereby congenital cataracts induce the unfolded protein response (UPR) and apoptosis to destroy the lens microarchitecture, while in age related cataract high molecular weight (HMW) aggregates formed by denatured crystallins bound by α-crystallin result in light scattering without severe damage to the lens microarchitecture.
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Affiliation(s)
- Alan Shiels
- Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, 63110, USA.
| | - J Fielding Hejtmancik
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892-1860, USA.
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Abstract
AIM Polymorphisms in alpha A crystallin (CRYAA) gene have been implicated in susceptibility to cataracts, but some published studies have reported inconclusive results. Our study aimed to conduct a meta-analysis investigating the association between polymorphisms in CRYAA and susceptibility to cataracts. METHODS The PubMed, Excerpta Medica Database, Cochrane Library and China National Knowledge Infrastructure were searched for all articles published up to 20 March 2019 that reported cataracts and three polymorphisms (rs3761381, rs13053109, and rs7278468) of CRYAA. Afterwards, statistical analysis was performed for available articles. RESULTS Four articles published between 2014 and 2017 were included, involving 869 cases and 1,950 controls. There was no statistical evidence of an association between cataract risk and CRYAA gene polymorphisms rs13053109 (p > .05) and rs3761382 (p > .05). Significant decreased cataract risks were observed for different gene models of rs7278468 polymorphism: for G vs T, OR = 0.6640; 95% CI, 0.5361-0.7736, p < .001; for GG vs TT, OR = 0.3864; 95% CI, 0.2379-0.6278, p < .001; for GG vs TT+GT, OR = 0.4492; 95% CI, 0.2829-0.7134, p = .001; for GG+GT vs TT, OR = 0.6645; 95% CI, 0.5058-0.8729, p = .003; for GT vs TT, OR = 0.7508; 95% CI, 0.5639-0.9996, p = .050. CONCLUSION Our meta-analysis indicated that rs3761382 and rs13053109 polymorphisms of CRYAA may not be associated with susceptibility to cataracts. Individuals carrying mutant genotype of rs7278468 polymorphism are associated with a significantly decreased cataract risk. ABBREVIATIONS CC: Congenital cataract; ARC: Age-related cataract; SNPs: single nucleotide polymorphisms; NOS: Newcastle-Ottawa Scale; HWE: Hardy-Weinberg equilibrium; OR: odds ratio; CI: confidence interval; qPCR: quantitative polymerase chain reaction; NO: nuclear opalescence; NC: nuclear color.
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Affiliation(s)
- Hongtao Yu
- Department of Ophthalmology, First Affiliated Hospital of Soochow University, Soochow, Jiangsu, China.,Department of Ophthalmology, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu, China
| | - Kaifeng Liu
- Department of Urology, Northern Jiangsu People's Hospital (NJPH), Clinical Medical School of Yangzhou University, Yangzhou, Jiangsu, PR China
| | - Peirong Lu
- Department of Ophthalmology, First Affiliated Hospital of Soochow University, Soochow, Jiangsu, China
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7
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Abstract
Cataract, the clinical correlate of opacity or light scattering in the eye lens, is usually caused by the presence of high-molecular-weight (HMW) protein aggregates or disruption of the lens microarchitecture. In general, genes involved in inherited cataracts reflect important processes and pathways in the lens including lens crystallins, connexins, growth factors, membrane proteins, intermediate filament proteins, and chaperones. Usually, mutations causing severe damage to proteins cause congenital cataracts, while milder variants increasing susceptibility to environmental insults are associated with age-related cataracts. These may have different pathogenic mechanisms: Congenital cataracts induce the unfolded protein response and apoptosis. By contrast, denatured crystallins in age-related cataracts are bound by α-crystallin and form light-scattering HMW aggregates. New therapeutic approaches to age-related cataracts use chemical chaperones to solubilize HMW aggregates, while attempts are being made to regenerate lenses using endogenous stem cells to treat congenital cataracts.
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Affiliation(s)
- Alan Shiels
- Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri 63110, USA;
| | - J Fielding Hejtmancik
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892-1860, USA;
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Zhu X, Zhang S, Chang R, Lu Y. New cataract markers: Mechanisms of disease. Clin Chim Acta 2017; 472:41-45. [PMID: 28705775 DOI: 10.1016/j.cca.2017.07.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 07/08/2017] [Accepted: 07/09/2017] [Indexed: 11/28/2022]
Abstract
Cataract is caused by nutritional, metabolic, environmental, and genetic factors, and is a significant cause of blindness and visual impairment. In recent years, extensive research into the human genome has revealed that numerous genetic mutations are associated with cataract. These mutations affect a variety of genes, including those encoding crystallin, membrane proteins, cytoskeletal proteins, transcription factors, and metabolism-related proteins. Elucidation of these mutations and the genetic and molecular mechanisms has helped clarify the etiology of cataract and may facilitate its early diagnosis and treatment. This review summarizes recent advances in our knowledge and potential clinical of genetic markers of cataract.
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Affiliation(s)
- Xiangjia Zhu
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China
| | - Shaohua Zhang
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China
| | - Ruiqi Chang
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China
| | - Yi Lu
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China.
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Patel R, Zenith RK, Chandra A, Ali A. Novel Mutations in the Crystallin Gene in Age-Related Cataract Patients from a North Indian Population. Mol Syndromol 2017; 8:179-186. [PMID: 28690483 DOI: 10.1159/000471992] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/13/2017] [Indexed: 12/17/2022] Open
Abstract
Cataract is the most prevalent leading cause of visual impairment and blindness worldwide. In comparison to congenital cataract, which affects relatively few individuals, age-related cataract is responsible for slightly half of all cases of blindness worldwide. Although significant work has been done, the genetic aspect of age-related cataract is still in its infancy. The current study was performed to analyze the mutations and polymorphisms in the CRYAA, CRYAB, CRYBB1, and GJA8 genes in 40 unrelated age-related cataract patients. Mutational analysis of the above-mentioned genes in 40 cataract cases revealed 14 different substitutions of which 8 variants were novel and 6 were reported SNPs. Two disease-causing mutations, g.44590631G>A (p.R65Q) and g.44592224G>A (p.R119H), were also observed in the CRYAA gene. The disease-causing variants mildly affect the stability, functionality, and localization of crystallin, and, with progressing age, a small change in the microenvironment of the crystallin lens occurs. This change in combination with a mutation may significantly alter the functionality of the crystallin protein, leading to age-related cataract.
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Affiliation(s)
- Rashmi Patel
- Centre for Genetic Disorders, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Ravish K Zenith
- Department of Ophthalmology, Sir Sunderlal Hospital, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | | | - Akhtar Ali
- Centre for Genetic Disorders, Institute of Science, Banaras Hindu University, Varanasi, India
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Shiels A, Hejtmancik JF. Mutations and mechanisms in congenital and age-related cataracts. Exp Eye Res 2017; 156:95-102. [PMID: 27334249 PMCID: PMC5538314 DOI: 10.1016/j.exer.2016.06.011] [Citation(s) in RCA: 136] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 06/09/2016] [Accepted: 06/16/2016] [Indexed: 01/06/2023]
Abstract
The crystalline lens plays an important role in the refractive vision of vertebrates by facilitating variable fine focusing of light onto the retina. Loss of lens transparency, or cataract, is a frequently acquired cause of visual impairment in adults and may also present during childhood. Genetic studies have identified mutations in over 30 causative genes for congenital or other early-onset forms of cataract as well as several gene variants associated with age-related cataract. However, the pathogenic mechanisms resulting from genetic determinants of cataract are only just beginning to be understood. Here, we briefly summarize current concepts pointing to differences in the molecular mechanisms underlying congenital and age-related forms of cataract.
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Affiliation(s)
- Alan Shiels
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - J Fielding Hejtmancik
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD 20892-1860, USA.
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11
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Ma X, Jiao X, Ma Z, Hejtmancik JF. Polymorphism rs7278468 is associated with Age-related cataract through decreasing transcriptional activity of the CRYAA promoter. Sci Rep 2016; 6:23206. [PMID: 26984531 PMCID: PMC4794711 DOI: 10.1038/srep23206] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 03/02/2016] [Indexed: 11/18/2022] Open
Abstract
CRYAA plays critical functional roles in lens transparency and opacity, and polymorphisms near CRYAA have been associated with age-related cataract (ARC). This study examines polymorphisms in the CRYAA promoter region for association with ARC and elucidates the mechanisms of this association. Three SNPs nominally associated with ARC were identified in the promoter region of CRYAA: rs3761382 (P = 0.06, OR (Odds ratio) = 1.5), rs13053109 (P = 0.04, OR = 1.6), rs7278468 (P = 0.007, OR = 0.6). The C-G-T haplotype increased the risk for ARC overall (P = 0.005, OR = 1.8), and both alleles and haplotypes show a stronger association with cortical cataract (rs3761382, P = 0.002, OR = 2.1; rs13053109, P = 0.002, OR = 2.1; rs7278468, P = 0.0007, OR = 0.5; C-G-T haplotype, P = 0.0003, OR = 2.2). The C-G-T risk haplotype decreased transcriptional activity through rs7278468, which lies in a consensus binding site for the transcription repressor KLF10. KLF10 binding inhibited CRYAA transcription, and both binding and inhibition were greater with the T rs7278468 allele. Knockdown of KLF10 in HLE cells partially rescued the transcriptional activity of CRYAA with rs7278468 T allele, but did not affect activity with the G allele. Thus, our data suggest that the T allele of rs7278468 in the CRYAA promoter is associated with ARC through increasing binding of KLF-10 and thus decreasing CRYAA transcription.
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Affiliation(s)
- Xiaoyin Ma
- Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, 325003, China.,Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xiaodong Jiao
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Zhiwei Ma
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - J Fielding Hejtmancik
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
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12
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Storey P, Munoz B, Friedman D, West S. Racial differences in lens opacity incidence and progression: the Salisbury Eye Evaluation (SEE) study. Invest Ophthalmol Vis Sci 2013; 54:3010-8. [PMID: 23572101 DOI: 10.1167/iovs.12-11412] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
PURPOSE To evaluate racial differences in nuclear and cortical lens opacity incidence and progression over a 2-year period in an older American population. METHODS Prospective population-based cohort study of a multiethnic population of 2520 people (26% African-American and 74% Caucasian), 65 to 84 years of age, living in Salisbury, Maryland. Data at baseline included race, education level, past steroid use, smoking status, alcohol status, sunlight exposure, and history of hypertension and diabetes. Lens photographs were taken at baseline and at 2-year follow-up and were graded using the Wilmer grading scheme. Multiple logistic regression models were used to examine the independent associations between race, as well as other risk factors, and incidence and progression of cortical and nuclear opacities. RESULTS AFRICAN-AMERICANS HAD LOWER RATES OF NUCLEAR OPACITY INCIDENCE (ODDS RATIO [OR]: 0.52; 95% Confidence Interval [CI]: 0.35-0.76) and nuclear opacity progression (OR: 0.60; 95% CI: 0.38-0.92) compared with Caucasians. African-Americans had higher rates of cortical opacity incidence (OR: 1.90; 95% CI: 1.21-2.98) and cortical opacity progression (OR: 1.72; 95% CI: 1.21-2.45) compared with Caucasians. Additionally, nuclear opacity incidence was associated with age, female sex, and current smoking status. Nuclear progression was associated with past smoking and current smoking. Cortical opacity incidence was associated with female sex, Ultraviolet-B exposure, and a history of diabetes. Cortical opacity progression was associated with current smoking status. CONCLUSIONS Differences by race in the type of cataract incidence and progression, even adjusting for personal and environmental risk factors, deserve further exploration.
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Affiliation(s)
- Philip Storey
- Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD 21287, USA
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