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Zhao Z, Chen J, Jiang Y, Lu Y. The E156K mutation in the CRYAA gene affects the epithelial-mesenchymal transition and migration of human lens epithelial cells. Heliyon 2024; 10:e23690. [PMID: 38187316 PMCID: PMC10770500 DOI: 10.1016/j.heliyon.2023.e23690] [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: 01/20/2023] [Revised: 11/30/2023] [Accepted: 12/09/2023] [Indexed: 01/09/2024] Open
Abstract
Purpose To investigated the biological effects of E156K-mutated αA-crystallin (CRYAA) in human lens epithelial cells (HLECs). Methods FLAG-tagged, human, full-length, wild-type (WT), or E156K-mutated CRYAA was expressed in HLECs under CRYAA knockdown. CRYAA expression was determined by quantitative reverse transcription polymerase chain reaction and western blotting (WB). Rhodamine cytoskeleton staining was used to observe the changes in cell morphology following transfection with WT or E156K-mutated CRYAA plasmids. WB was performed to assess the expression of markers related to epithelial-mesenchymal transition (EMT) and migration. Results Rhodamine cytoskeleton staining revealed changes in the morphology of cells transfected with E156K-mutated CRYAA and opposite responses occurred after treatment with a β-catenin inhibitor. Cells transfected with E156K-mutated CRYAA expressed remarkably higher levels of the mesenchymal biomarkers N-cadherin and vimentin but decreased levels of the epithelial biomarker E-cadherin, whereas opposite trends were observed in cells treated with the β-catenin inhibitor, ICG001. The migratory capability of E156K-mutated CRYAA cells was significantly greater than that of WT cells (P < 0.001). This effect was accompanied by significantly increased expression levels of phosphorylated (p)-focal adhesion kinase (FAK) and p-Src. These changes were decreased significantly by treatment with FAK and Src inhibitors. Conclusion E156K-mutated CRYAA induced EMT, in which the HLECs lost cell polarity, and acquired a mesenchymal phenotype with greater migratory capability. These biological effects may be associated with activation of the Wnt/β-Catenin and FAK/Src signaling pathways.
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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
| | - 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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Zafar S, Khurram H, Kamran M, Fatima M, Parvaiz A, Shaikh RS. Potential of GJA8 gene variants in predicting age-related cataract: A comparison of supervised machine learning methods. PLoS One 2023; 18:e0286243. [PMID: 37651414 PMCID: PMC10470928 DOI: 10.1371/journal.pone.0286243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 05/11/2023] [Indexed: 09/02/2023] Open
Abstract
Cataracts are the problems associated with the crystallins proteins of the eye lens. Any perturbation in the conformity of these proteins results in a cataract. Age-related cataract is the most common type among all cataracts as it accounts for almost 80% of cases of senile blindness worldwide. This research study was performed to predict the role of single nucleotide polymorphisms (SNPs) of the GJA8 gene with age-related cataracts in 718 subjects (400 age-related cataract patients and 318 healthy individuals). A comparison of supervised machine learning classification algorithm including logistic regression (LR), random forest (RF) and Artificial Neural Network (ANN) were presented to predict the age-related cataracts. The results indicated that LR is the best for predicting age-related cataracts. This successfully developed model after accounting different genetic and demographic factors to predict cataracts will help in effective disease management and decision-making medical practitioner and experts.
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Affiliation(s)
- Saba Zafar
- Department of Biochemistry and Biotechnology, The Women University, Multan, Pakistan
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Pakistan
| | - Haris Khurram
- Department of Sciences and Humanities, National University of Computer and Emerging Sciences, Chiniot-Faisalabad Campus, Chiniot, Pakistan
| | - Muhammad Kamran
- Department of Medical Laboratory Technology, Islamabad Medical & Dental college, Islamabad, Pakistan
| | - Madeeha Fatima
- Department of Zoology, The Women University, Multan, Pakistan
| | - Aqsa Parvaiz
- Department of Biochemistry and Biotechnology, The Women University, Multan, Pakistan
| | - Rehan Sadiq Shaikh
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Pakistan
- Center for Applied Molecular Biology, University of the Punjab, Lahore, Pakistan
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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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Grosas AB, Rekas A, Mata JP, Thorn DC, Carver JA. The Aggregation of αB-Crystallin under Crowding Conditions Is Prevented by αA-Crystallin: Implications for α-Crystallin Stability and Lens Transparency. J Mol Biol 2020; 432:5593-5613. [PMID: 32827531 DOI: 10.1016/j.jmb.2020.08.011] [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: 06/05/2020] [Revised: 08/13/2020] [Accepted: 08/13/2020] [Indexed: 02/08/2023]
Abstract
One of the most crowded biological environments is the eye lens which contains a high concentration of crystallin proteins. The molecular chaperones αB-crystallin (αBc) with its lens partner αA-crystallin (αAc) prevent deleterious crystallin aggregation and cataract formation. However, some forms of cataract are associated with structural alteration and dysfunction of αBc. While many studies have investigated the structure and function of αBc under dilute in vitro conditions, the effect of crowding on these aspects is not well understood despite its in vivo relevance. The structure and chaperone ability of αBc under conditions that mimic the crowded lens environment were investigated using the polysaccharide Ficoll 400 and bovine γ-crystallin as crowding agents and a variety of biophysical methods, principally contrast variation small-angle neutron scattering. Under crowding conditions, αBc unfolds, increases its size/oligomeric state, decreases its thermal stability and chaperone ability, and forms kinetically distinct amorphous and fibrillar aggregates. However, the presence of αAc stabilizes αBc against aggregation. These observations provide a rationale, at the molecular level, for the aggregation of αBc in the crowded lens, a process that exhibits structural and functional similarities to the aggregation of cataract-associated αBc mutants R120G and D109A under dilute conditions. Strategies that maintain or restore αBc stability, as αAc does, may provide therapeutic avenues for the treatment of cataract.
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Affiliation(s)
- Aidan B Grosas
- Research School of Chemistry, The Australian National University, Canberra, ACT, 2601, Australia
| | - Agata Rekas
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234, Australia
| | - Jitendra P Mata
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234, Australia
| | - David C Thorn
- Research School of Chemistry, The Australian National University, Canberra, ACT, 2601, Australia
| | - John A Carver
- Research School of Chemistry, The Australian National University, Canberra, ACT, 2601, Australia.
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Periyasamy P, Shinohara T. Age-related cataracts: Role of unfolded protein response, Ca 2+ mobilization, epigenetic DNA modifications, and loss of Nrf2/Keap1 dependent cytoprotection. Prog Retin Eye Res 2017; 60:1-19. [PMID: 28864287 PMCID: PMC5600869 DOI: 10.1016/j.preteyeres.2017.08.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 08/26/2017] [Accepted: 08/28/2017] [Indexed: 12/11/2022]
Abstract
Age-related cataracts are closely associated with lens chronological aging, oxidation, calcium imbalance, hydration and crystallin modifications. Accumulating evidence indicates that misfolded proteins are generated in the endoplasmic reticulum (ER) by most cataractogenic stresses. To eliminate misfolded proteins from cells before they can induce senescence, the cells activate a clean-up machinery called the ER stress/unfolded protein response (UPR). The UPR also activates the nuclear factor-erythroid-2-related factor 2 (Nrf2), a central transcriptional factor for cytoprotection against stress. Nrf2 activates nearly 600 cytoprotective target genes. However, if ER stress reaches critically high levels, the UPR activates destructive outputs to trigger programmed cell death. The UPR activates mobilization of ER-Ca2+ to the cytoplasm and results in activation of Ca2+-dependent proteases to cleave various enzymes and proteins which cause the loss of normal lens function. The UPR also enhances the overproduction of reactive oxygen species (ROS), which damage lens constituents and induce failure of the Nrf2 dependent cytoprotection. Kelch-like ECH-associated protein 1 (Keap1) is an oxygen sensor protein and regulates the levels of Nrf2 by the proteasomal degradation. A significant loss of DNA methylation in diabetic cataracts was found in the Keap1 promoter, which overexpresses the Keap1 protein. Overexpressed Keap1 significantly decreases the levels of Nrf2. Lower levels of Nrf2 induces loss of the redox balance toward to oxidative stress thereby leading to failure of lens cytoprotection. Here, this review summarizes the overall view of ER stress, increases in Ca2+ levels, protein cleavage, and loss of the well-established stress protection in somatic lens cells.
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Affiliation(s)
- Palsamy Periyasamy
- Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Toshimichi Shinohara
- Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68198, USA
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Functional non-coding polymorphism in an EPHA2 promoter PAX2 binding site modifies expression and alters the MAPK and AKT pathways. Sci Rep 2017; 7:9992. [PMID: 28855599 PMCID: PMC5577203 DOI: 10.1038/s41598-017-10117-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 08/04/2017] [Indexed: 01/11/2023] Open
Abstract
To identify possible genetic variants influencing expression of EPHA2 (Ephrin-receptor Type-A2), a tyrosine kinase receptor that has been shown to be important for lens development and to contribute to both congenital and age related cataract when mutated, the extended promoter region of EPHA2 was screened for variants. SNP rs6603883 lies in a PAX2 binding site in the EPHA2 promoter region. The C (minor) allele decreased EPHA2 transcriptional activity relative to the T allele by reducing the binding affinity of PAX2. Knockdown of PAX2 in human lens epithelial (HLE) cells decreased endogenous expression of EPHA2. Whole RNA sequencing showed that extracellular matrix (ECM), MAPK-AKT signaling pathways and cytoskeleton related genes were dysregulated in EPHA2 knockdown HLE cells. Taken together, these results indicate a functional non-coding SNP in EPHA2 promoter affects PAX2 binding and reduces EPHA2 expression. They further suggest that decreasing EPHA2 levels alters MAPK, AKT signaling pathways and ECM and cytoskeletal genes in lens cells that could contribute to cataract. These results demonstrate a direct role for PAX2 in EPHA2 expression and help delineate the role of EPHA2 in development and homeostasis required for lens transparency.
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Santhoshkumar P, Karmakar S, Sharma KK. Structural and functional consequences of chaperone site deletion in αA-crystallin. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2016; 1864:1529-38. [PMID: 27524665 DOI: 10.1016/j.bbapap.2016.08.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/05/2016] [Accepted: 08/09/2016] [Indexed: 01/29/2023]
Abstract
The chaperone-like activity of αA-crystallin has an important role in maintaining lens transparency. Previously we identified residues 70-88 as a chaperone site in αA-crystallin. In this study, we deleted the chaperone site residues to generate αAΔ70-76 and αAΔ70-88 mutants and investigated if there are additional substrate-binding sites in αA-crystallin. Both mutant proteins when expressed in E. coli formed inclusion bodies, and on solubilizing and refolding, they exhibited similar structural properties, with a 2- to 3-fold increase in molar mass compared to the molar mass of wild-type protein. The deletion mutants were less stable than the wild-type αA-crystallin. Functionally αAΔ70-88 was completely inactive as a chaperone, while αAΔ70-76 demonstrated a 40-50% reduction in anti-aggregation activity against alcohol dehydrogenase (ADH). Deletion of residues 70-88 abolished the ADH binding sites in αA-crystallin at physiological temperature. At 45°C, cryptic ADH binding site(s) became exposed, which contributed subtly to the chaperone-like activity of αAΔ70-88. Both of the deletion mutants were completely inactive in suppressing aggregation of βL-crystallin at 53°C. The mutants completely lost the anti-apoptotic property that αA-crystallin exhibits while they protected ARPE-19 (a human retinal pigment epithelial cell line) and primary human primary lens epithelial (HLE) cells from oxidative stress. Our studies demonstrate that residues 70-88 in αA-crystallin act as a primary substrate binding site and account for the bulk of the total chaperone activity. The β3 and β4 strands in αA-crystallin comprising 70-88 residues play an important role in maintenance of the structure and in preventing aggregation of denaturing proteins.
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Affiliation(s)
- Puttur Santhoshkumar
- Department of Ophthalmology, University of Missouri School of Medicine, Columbia, MO 65212, United States.
| | - Srabani Karmakar
- Department of Ophthalmology, University of Missouri School of Medicine, Columbia, MO 65212, United States
| | - Krishna K Sharma
- Department of Ophthalmology, University of Missouri School of Medicine, Columbia, MO 65212, United States; Department of Biochemistry, University of Missouri School of Medicine, Columbia, MO 65212, United States.
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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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Abstract
Lens opacities or cataract(s) represent a universally important cause of visual impairment and blindness. Typically, cataract is acquired with aging as a complex disorder involving environmental and genetic risk factors. Cataract may also be inherited with an early onset either in association with other ocular and/or systemic abnormalities or as an isolated lens phenotype. Here we briefly review recent advances in gene discovery for inherited and age-related forms of cataract that are providing new insights into lens development and aging.
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Ramkumar S, Thankappan B, Fujii N, Natarajaseenivasan K, Anbarasu K. Interaction of αA-crystallin F71L mutant with wild type αA- and αB-crystallins by mammalian two hybrid assay. Int J Biol Macromol 2015; 76:102-8. [DOI: 10.1016/j.ijbiomac.2015.02.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 02/13/2015] [Accepted: 02/16/2015] [Indexed: 11/26/2022]
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Reddy PY, Giridharan NV, Balakrishna N, Validandi V, Pullakhandam R, Reddy GB. Increased risk of cataract development in WNIN-obese rats due to accumulation of intralenticular sorbitol. IUBMB Life 2013; 65:472-8. [PMID: 23504868 DOI: 10.1002/iub.1163] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Revised: 01/26/2013] [Accepted: 01/31/2013] [Indexed: 11/08/2022]
Abstract
Epidemiological studies have reported an association between obesity and increased incidence of ocular complications including cataract, yet the underlying biochemical and molecular mechanisms remained unclear. Previously we had demonstrated accumulation of sorbitol in the lens of obese rats (WNIN/Ob) and more so in a related strain with impaired glucose tolerance (WNIN/GR-Ob). However, only a few (15-20%) WNIN/Ob and WNIN/GR-Ob rats develop cataracts spontaneously with age. To gain further insights, we investigated the susceptibility of eye lens proteins of these obese rat strains to heat- and UV-induced aggregation in vitro, lens opacification upon glucose-mediated sorbitol accumulation ex vivo, and onset and progression of cataract was followed by galactose feeding and streptozotocin (STZ) injection. The results indicated increased susceptibility toward heat- or UV-induced aggregation of lens proteins in obese animals compared to their littermate lean controls. Further, in organ culture studies glucose-induced sorbitol accumulation was found to be higher and thus the lens opacification was faster in obese animals compared to their lean littermates. Also, the onset and progression of galactose- or STZ-induced cataractogenesis was faster in obese animals compared to lean control. These results together with our previous observations suggest that obesity status could lead to hyperaccumulation of sorbitol in eye lens, predisposing them to cataract, primarily by increasing their susceptibility to environmental and/or physiological factors. Further, intralenticular sorbitol accumulation beyond a threshold level could lead to cataract in WNIN/Ob and WNIN/GR-Ob rats.
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Datskevich PN, Nefedova VV, Sudnitsyna MV, Gusev NB. Mutations of small heat shock proteins and human congenital diseases. BIOCHEMISTRY (MOSCOW) 2013; 77:1500-14. [DOI: 10.1134/s0006297912130081] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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