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Loo Y, Chan ASY, Khor CC, Aung T, Wang Z. Rodent genetically modified models of glaucoma. Mol Aspects Med 2024; 95:101229. [PMID: 38039744 DOI: 10.1016/j.mam.2023.101229] [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: 07/11/2023] [Revised: 11/11/2023] [Accepted: 11/15/2023] [Indexed: 12/03/2023]
Abstract
Glaucoma, one of the leading causes of irreversible blindness worldwide, is a complex and heterogenous disease. While environmental factors are important, it is well-recognized that the disease has a strong heritable component. With the advent of large-cohort genome wide association studies, a myriad of genetic risk loci has been linked to different forms of glaucoma. Animal models have been an indispensable tool in characterizing these loci, especially if they lie within coding regions in the genome. Not only do these models connect genotype to phenotype, advancing our understanding of glaucoma pathogenesis in the process, they also have valuable utility as a platform for the pre-clinical testing of potential therapies. In this review, we will outline genetic models used for studying the major forms of glaucoma, including primary open angle glaucoma, normal tension glaucoma, primary angle closure glaucoma, pigmentary glaucoma, pseudoexfoliation glaucoma, and early onset glaucoma, including congenital and developmental glaucoma, and how studying these models have helped shed light on human glaucoma.
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Affiliation(s)
- Yunhua Loo
- Duke-NUS Medical School, Singapore; Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Anita Sook Yee Chan
- Duke-NUS Medical School, Singapore; Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Chiea Chuen Khor
- Duke-NUS Medical School, Singapore; Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore; Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Tin Aung
- Duke-NUS Medical School, Singapore; Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Zhenxun Wang
- Duke-NUS Medical School, Singapore; Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore; Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.
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2
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De Ieso ML, Kelly R, Mzyk P, Stamer WD. Development and testing of a metabolic chamber for effluent collection during whole eye perfusions. Exp Eye Res 2023; 236:109652. [PMID: 37717688 PMCID: PMC10842592 DOI: 10.1016/j.exer.2023.109652] [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: 05/17/2023] [Revised: 09/10/2023] [Accepted: 09/12/2023] [Indexed: 09/19/2023]
Abstract
Ocular hypertension is caused by dysregulated outflow resistance regulation by the conventional outflow (CO) pathway. The physiology of the CO pathway can be directly studied during ex vivo ocular perfusions. In addition to measuring outflow resistance generation by the CO tissues, perfusion media that is conditioned by CO pathway cells can be collected upon exiting the eye as effluent. Thus, contents of effluent include factors contributed by upstream cells that report on the (dys)functionality of the outflow tissues. Two methods have been used in the past to monitor effluent contents from perfused eyes, each with their limitations. To overcome these limitations, we designed and printed a metabolic chamber to accommodate eyes of different sizes during perfusions. To test this new chamber, human eyes were perfused for 4 h at constant flow rate of 2.5 μl/min, while pressure was continuously monitored and effluent was collected every hour. Facility was 0.28 ± 0.16 μl/min/mmHg for OD eyes and 0.33 ± 0.11 μl/min/mmHg for OS eyes (n = 3). Effluent samples were protein rich, with protein concentration ranging from 2700 to 10,000 μg/ml for all eyes and timepoints (N = 3). Effluent samples expressed proteins that were actively secreted by the TM and easily detectible including MYOC and MMP2. Taken together, our model provides a reliable method to collect effluent from ex vivo human eyes, while maintaining whole globe integrity.
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Affiliation(s)
- Michael L De Ieso
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, United States.
| | - Ruth Kelly
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, United States.
| | - Philip Mzyk
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, United States.
| | - W Daniel Stamer
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, United States.
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3
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Hassan MDS, Razali N, Abu Bakar AS, Abu Hanipah NF, Agarwal R. Connective tissue growth factor: Role in trabecular meshwork remodeling and intraocular pressure lowering. Exp Biol Med (Maywood) 2023; 248:1425-1436. [PMID: 37873757 PMCID: PMC10657592 DOI: 10.1177/15353702231199466] [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] [Indexed: 10/25/2023] Open
Abstract
Connective tissue growth factor (CTGF) is a distinct signaling molecule modulating many physiological and pathophysiological processes. This protein is upregulated in numerous fibrotic diseases that involve extracellular matrix (ECM) remodeling. It mediates the downstream effects of transforming growth factor beta (TGF-β) and is regulated via TGF-β SMAD-dependent and SMAD-independent signaling routes. Targeting CTGF instead of its upstream regulator TGF-β avoids the consequences of interfering with the pleotropic effects of TGF-β. Both CTGF and its upstream mediator, TGF-β, have been linked with the pathophysiology of glaucomatous optic neuropathy due to their involvement in the regulation of ECM homeostasis. The excessive expression of these growth factors is associated with glaucoma pathogenesis via elevation of the intraocular pressure (IOP), the most important risk factor for glaucoma. The raised in the IOP is due to dysregulation of ECM turnover resulting in excessive ECM deposition at the site of aqueous humor outflow. It is therefore believed that CTGF could be a potential therapeutic target in glaucoma therapy. This review highlights the CTGF biology and structure, its regulation and signaling, its association with the pathophysiology of glaucoma, and its potential role as a therapeutic target in glaucoma management.
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Affiliation(s)
| | - Norhafiza Razali
- Institute of Medical Molecular Biotechnology (IMMB), Universiti Teknologi MARA (UiTM), 47000 Sungai Buloh, Malaysia
- Department of Pharmacology, Faculty of Medicine, Universiti Teknologi MARA (UiTM), 47000 Sungai Buloh, Malaysia
- Center for Neuroscience Research (NeuRon), Faculty of Medicine, Universiti Teknologi MARA (UiTM), 47000 Sungai Buloh, Malaysia
| | - Amy Suzana Abu Bakar
- Institute of Medical Molecular Biotechnology (IMMB), Universiti Teknologi MARA (UiTM), 47000 Sungai Buloh, Malaysia
- Center for Neuroscience Research (NeuRon), Faculty of Medicine, Universiti Teknologi MARA (UiTM), 47000 Sungai Buloh, Malaysia
| | - Noor Fahitah Abu Hanipah
- Institute of Medical Molecular Biotechnology (IMMB), Universiti Teknologi MARA (UiTM), 47000 Sungai Buloh, Malaysia
- Department of Pharmacology, Faculty of Medicine, Universiti Teknologi MARA (UiTM), 47000 Sungai Buloh, Malaysia
| | - Renu Agarwal
- School of Medicine, International Medical University (IMU), 57000 Kuala Lumpur, Malaysia
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Palchunova K, Kaji Y, Fujita A, Oshika T. RNA-seq analysis of human trabecular endothelial cells after treatment with timolol maleate. Jpn J Ophthalmol 2023:10.1007/s10384-023-00998-5. [PMID: 37314597 DOI: 10.1007/s10384-023-00998-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 04/26/2023] [Indexed: 06/15/2023]
Abstract
PURPOSE Timolol maleate (timolol), a β-receptor blocker, reduces intraocular pressure by decreasing aqueous humor production. Timolol reportedly also protects ganglion cells, decreases aqueous humor outflow facility, and destroys the extracellular matrix in the trabecular meshwork. In this study, we investigated the effects of timolol on cultured human trabecular endothelial cells purchased from ScienCell using next-generation sequencing. STUDY DESIGN Experimental investigation. METHODS Total ribonucleic acid (RNA) was extracted after 24 h. More than 100 million RNAs in control and timolol-treated group were sequenced using a next-generation sequencer. The expression of 55,778 RNAs was analyzed. RESULTS A total of 2,105 genes were significantly upregulated and 2,125 genes were downregulated, after the addition of timolol. VGF nerve growth factor inducible (VGF) (388-fold) had the maximum increase in expression, followed by amphiregulin (333-fold), a member of the epidermal growth factor family. Moreover, the expression of extracellular matrix-degrading enzymes, matrix metalloproteinases (MMPs) 1, 2, 3, 10, 12, and 14, increased. CONCLUSION Timolol exerts various effects on human trabecular endothelial cells. The increase in MMP expression may contribute to the decrease in the aqueous humor outflow facility.
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Affiliation(s)
- Kseniya Palchunova
- Department of Ophthalmology, University of Tsukuba Majors in Medical Sciences, 1-1-1 Tennoudai Tsukuba, Ibaraki, 3058575, Japan
| | - Yuichi Kaji
- Department of Ophthalmology, University of Tsukuba Majors in Medical Sciences, 1-1-1 Tennoudai Tsukuba, Ibaraki, 3058575, Japan.
- Matsumoto Eye Clinic, 2-25-2F Toride-i-center, Chuo-machi Toride, Ibaraki, 3020014, Japan.
| | - Akari Fujita
- Kagurazaka Eye Clinic, 115 Yarai-cho Shinjyuku, Tokyo, 1620805, Japan
| | - Tetsuro Oshika
- Department of Ophthalmology, University of Tsukuba Majors in Medical Sciences, 1-1-1 Tennoudai Tsukuba, Ibaraki, 3058575, Japan
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Beardslee LA, Halman JR, Unser AM, Xie Y, Danias J, Bergkvist M, Sharfstein ST, Torrejon KY. Recreating the Trabecular Outflow Tissue on Implantable, Micropatterned, Ultrathin, Porous Polycaprolactone Scaffolds. Bioengineering (Basel) 2023; 10:679. [PMID: 37370610 DOI: 10.3390/bioengineering10060679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 05/17/2023] [Accepted: 05/28/2023] [Indexed: 06/29/2023] Open
Abstract
Glaucoma, where increased intraocular pressure (IOP) leads to damage to the optic nerve and loss of sight, is amongst the foremost causes of irreversible blindness worldwide. In primary open angle glaucoma, the increased IOP is a result of the malfunctioning human trabecular meshwork (HTM) cells' inability to properly regulate the outflow of aqueous humor from the eye. A potential future treatment for glaucoma is to replace damaged HTM cells with a tissue-engineered substitute, thus restoring proper fluid outflow. Polycaprolactone (PCL) is a versatile, biodegradable, and implantable material that is widely used for cell culture and tissue engineering. In this work, PCL scaffolds were lithographically fabricated using a sacrificial process to produce submicron-thick scaffolds with openings of specific sizes and shapes (e.g., grid, hexagonal pattern). The HTM cell growth on gelatin-coated PCL scaffolds was assessed by scanning electron microscopy, tetrazolium metabolic activity assay, and cytoskeletal organization of F-actin. Expression of HTM-specific markers and ECM deposition were assessed by immunocytochemistry and qPCR analysis. Gelatin-coated, micropatterned, ultrathin, porous PCL scaffolds with a grid pattern supported proper HTM cell growth, cytoskeleton organization, HTM-marker expression, and ECM deposition, demonstrating the feasibility of using these PCL scaffolds to tissue-engineer implantable, healthy ocular outflow tissue.
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Affiliation(s)
- Luke A Beardslee
- Colleges of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY 12203, USA
| | - Justin R Halman
- Colleges of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY 12203, USA
| | - Andrea M Unser
- Department of Ophthalmology, SUNY Downstate Health Sciences University, 450 Clackson Avenue, Brooklyn, NY 11203, USA
| | - Yubing Xie
- Colleges of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY 12203, USA
| | - John Danias
- Department of Ophthalmology, SUNY Downstate Health Sciences University, 450 Clackson Avenue, Brooklyn, NY 11203, USA
| | - Magnus Bergkvist
- Colleges of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY 12203, USA
| | - Susan T Sharfstein
- Colleges of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY 12203, USA
| | - Karen Y Torrejon
- Colleges of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY 12203, USA
- Glauconix Biosciences Inc., 251 Fuller Road, Albany, NY 12203, USA
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Dillinger AE, Kuespert S, Seleem AA, Neuendorf J, Schneider M, Fuchshofer R. CCN2/CTGF tip the balance of growth factors towards TGF-β2 in primary open-angle glaucoma. Front Mol Biosci 2023; 10:1045411. [PMID: 37251082 PMCID: PMC10210157 DOI: 10.3389/fmolb.2023.1045411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 04/28/2023] [Indexed: 05/31/2023] Open
Abstract
TGF-β2 is the predominant TGF-β isoform within the eye. One function of TGF-β2 is to provide the eye with immune protection against intraocular inflammation. The beneficial function of TGF-β2 within the eye must be under tight control of a network of different factors. A disbalance of the network can result in different eye diseases. In Primary Open-Angle Glaucoma (POAG), one of the leading causes of irreversible blindness worldwide, TGF-β2 is significantly elevated in the aqueous humor and antagonistic molecules like BMPs are reduced. The changes provoke an altering of the quantity and quality of the extracellular matrix and the actin cytoskeleton in the outflow tissues, leading to an increased outflow resistance and thereby to an increased intraocular pressure (IOP), the major risk factor for primary open-angle glaucoma. The pathologic effect of TGF-β2 in primary open-angle glaucoma is mainly meditated by CCN2/CTGF. CCN2/CTGF can modulate TGF-β and BMP signaling by direct binding. The eye specific overexpression of CCN2/CTGF caused an increase in IOP and led to a loss of axons, the hallmark of primary open-angle glaucoma. CCN2/CTGF appears to play a critical role in the homeostatic balance of the eye, so we investigated if CCN2/CTGF can modulate BMP and TGF-β signaling pathways in the outflow tissues. To this end, we analyzed the direct effect of CCN2/CTGF on both signaling pathways in two transgenic mouse models with a moderate (βB1-CTGF1) and a high CCN2/CTGF (βB1-CTGF6) overexpression and in immortalized human trabecular meshwork (HTM) cells. Additionally, we investigate whether CCN2/CTGF mediates TGF-β effects via different pathways. We observed developmental malformations in the ciliary body in βB1-CTGF6 caused by an inhibition of the BMP signaling pathway. In βB1-CTGF1, we detected a dysregulation of the BMP and TGF-β signaling pathways, with reduced BMP activity and increased TGF-β signaling. A direct CCN2/CTGF effect on BMP and TGF-β signaling was shown in immortalized HTM cells. Finally, CCN2/CTGF mediated its effects on TGF-β via the RhoA/ROCK and ERK signaling in immortalized HTM cells. We conclude that CCN2/CTGF functions as a modulator of the homeostatic balance of BMP and TGF-β signaling pathways, which is shifted in primary open-angle glaucoma.
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Affiliation(s)
- Andrea E. Dillinger
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Sabrina Kuespert
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Amin A. Seleem
- Zoology Department, Faculty of Science, Sohag University, Sohag, Egypt
- Biology Department, Faculty of Science and Arts, Al Ula, Taibah University, Almadinah Almunawwarah, Saudi Arabia
| | - Jakob Neuendorf
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Magdalena Schneider
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Rudolf Fuchshofer
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
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7
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Ing E, Lozano DC, Cepurna WO, Chan F, Yang YF, Morrison JC, Keller KE. A method describing the microdissection of trabecular meshwork tissue from Brown Norway rat eyes. Exp Eye Res 2023; 228:109367. [PMID: 36740159 PMCID: PMC9991013 DOI: 10.1016/j.exer.2022.109367] [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: 09/20/2022] [Revised: 11/29/2022] [Accepted: 12/23/2022] [Indexed: 02/05/2023]
Abstract
Glaucoma is often associated with elevated intraocular pressure (IOP), generally due to obstruction of aqueous humor outflow within the trabecular meshwork (TM). Despite many decades of research, the molecular cause of this obstruction remains elusive. To study IOP regulation, several in vitro models, such as perfusion of anterior segments or mechanical stretching of TM cells, have identified several IOP-responsive genes and proteins. While these studies have proved informative, they do not fully recapitulate the in vivo environment where IOP is subject to additional factors, such as circadian rhythms. Thus, rodent animal models are now commonly used to study IOP-responsive genes in vivo. Several single-cell RNAseq studies have been performed where angle tissue, containing cornea, iris, ciliary body tissue in addition to TM, is dissected. However, it is advantageous to physically separate TM from other tissues because the ratio of TM cells is relatively low compared to the other cell types. In this report, we describe a new technique for rat TM microdissection. Evaluating tissue post-dissection by histology and immunostaining clearly shows successful removal of the TM. In addition, TaqMan PCR primers targeting biomarkers of trabecular meshwork (Myoc, Mgp, Chi3l1) or ciliary body (Myh11, Des) genes showed little contamination of TM tissue by the ciliary body. Finally, pitfalls encountered during TM microdissection are discussed to enable others to successfully perform this microsurgical technique in the rat eye.
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Affiliation(s)
- Eliesa Ing
- Casey Eye Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Diana C Lozano
- Casey Eye Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - William O Cepurna
- Casey Eye Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Fountane Chan
- Casey Eye Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Yong-Feng Yang
- Casey Eye Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - John C Morrison
- Casey Eye Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Kate E Keller
- Casey Eye Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA.
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MiR-18a-5p Targets Connective Tissue Growth Factor Expression and Inhibits Transforming Growth Factor β2-Induced Trabecular Meshwork Cell Contractility. Genes (Basel) 2022; 13:genes13081500. [PMID: 36011411 PMCID: PMC9408287 DOI: 10.3390/genes13081500] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/16/2022] [Accepted: 08/17/2022] [Indexed: 12/22/2022] Open
Abstract
Increased trabecular meshwork (TM) cell and tissue contractility is a driver of the reduced outflow facility and elevation of intraocular pressure (IOP) associated with primary open-angle glaucoma (POAG). Connective tissue growth factor (CTGF) is an established mediator of TM cell contractility, and its expression is increased in POAG due to transforming growth factor β 2 (TGFβ2) signalling. Inhibiting CTGF upregulation using microRNA (miRNA) mimetics could represent a new treatment option for POAG. A combination of in silico predictive tools and a literature review identified a panel of putative CTGF-targeting miRNAs. Treatment of primary human TM cells with 5 ng/mL TGFβ2 for 24 h identified miR-18a-5p as a consistent responder, being upregulated in cells from five different human donors. Transfection of primary donor TM cells with 20 nM synthetic miR-18a-5p mimic reduced TGFβ2-induced CTGF protein expression, and stable lentiviral-mediated overexpression of this miRNA reduced TGFβ2-induced contraction of collagen gels. Together, these findings identify miR-18a-5p as a mediator of the TGFβ2 response and a candidate therapeutic agent for glaucoma via its ability to inhibit CTGF-associated increased TM contractility.
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9
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Animal Model Contributions to Primary Congenital Glaucoma. J Ophthalmol 2022; 2022:6955461. [PMID: 35663518 PMCID: PMC9162845 DOI: 10.1155/2022/6955461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 05/12/2022] [Indexed: 11/17/2022] Open
Abstract
Primary congenital glaucoma (PCG) is an ocular disease characterized by congenital anterior segmental maldevelopment with progressive optic nerve degeneration. Certain genes, such as cytochrome P450 family 1 subfamily B member 1 and latent TGF-β-binding protein 2, are involved in the pathogenesis of PCG, but the exact pathogenic mechanism has not yet been fully elucidated. There is an urgent need to determine the etiology and pathophysiology of PCG and develop new therapeutic methods to stop disease progression. Animal models can simulate PCG and are essential to study the pathogenesis and treatment of PCG. Various animal species have been used in the study of PCG, including rabbits, rats, mice, cats, zebrafish, and quails. These models are formed spontaneously or by combining with genetic engineering technology. The focus of the present study is to review the characteristics and potential applications of animal models in PCG and provide new approaches to understand the mechanism and develop new treatment strategies for patients with PCG.
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10
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Dillinger AE, Weber GR, Mayer M, Schneider M, Göppner C, Ohlmann A, Shamonin M, Monkman GJ, Fuchshofer R. CCN2/CTGF—A Modulator of the Optic Nerve Head Astrocyte. Front Cell Dev Biol 2022; 10:864433. [PMID: 35493079 PMCID: PMC9047870 DOI: 10.3389/fcell.2022.864433] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/18/2022] [Indexed: 12/14/2022] Open
Abstract
In primary open-angle glaucoma (POAG), a neurodegenerative disease of the optic nerve (ON) and leading cause of blindness, the optic nerve head (ONH) undergoes marked structural extracellular matrix (ECM) changes, which contribute to its permanent deformation and to degeneration of ON axons. The remodeling process of the ECM causes changes in the biomechanical properties of the ONH and the peripapillary sclera, which is accompanied by an increased reactivity of the resident astrocytes. The molecular factors involved in the remodeling process belong to the Transforming growth factor (TGF)-β superfamily, especially TGF-β2. In previous publications we showed that TGF-β2 induced ECM alterations are mediated by Cellular Communication Network Factor (CCN)2/Connective Tissue Growth Factor (CTGF) and recently we showed that CCN2/CTGF is expressed by astrocytes of the ON under normal conditions. In this study we wanted to get a better understanding of the function of CCN2/CTGF under normal and pathologic conditions. To this end, we analyzed the glial lamina and peripapillary sclera of CCN2/CTGF overexpressing mice and studied the effect of CCN2/CTGF and increasing substratum stiffness on murine ON astrocytes in vitro. We observed enhanced astrocyte reactivity in the ONH, increased ECM protein synthesis in the peripapillary sclera and increased Ccn2/Ctgf expression in the ONH during the pathologic development in situ. CCN2/CTGF treatment of primary murine ON astrocytes induced a higher migration rate, and increase of ECM proteins including fibronectin, elastin and collagen type III. Furthermore, the astrocytes responded to stiffer substratum with increased glial fibrillary acidic protein, vimentin, actin and CCN2/CTGF synthesis. Finally, we observed the reinforced appearance of CCN2/CTGF in the lamina cribrosa of glaucomatous patients. We conclude that reactive changes in ONH astrocytes, induced by the altered biomechanical characteristics of the region, give rise to a self-amplifying process that includes increased TGF-β2/CCN2/CTGF signaling and leads to the synthesis of ECM molecules and cytoskeleton proteins, a process that in turn augments the stiffness at the ONH. Such a scenario may finally result in a vicious circle in the pathogenesis of POAG. The transgenic CTGF-overexpressing mouse model might be an optimal model to study the chronic pathological POAG changes in the ONH.
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Affiliation(s)
- Andrea E. Dillinger
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Gregor R. Weber
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Matthias Mayer
- Faculty of Electrical Engineering and Information Technology, Ostbayerische Technische Hochschule Regensburg, Regensburg, Germany
| | - Magdalena Schneider
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Corinna Göppner
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Andreas Ohlmann
- Department of Ophthalmology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Mikhail Shamonin
- Faculty of Electrical Engineering and Information Technology, Ostbayerische Technische Hochschule Regensburg, Regensburg, Germany
| | - Gareth J. Monkman
- Faculty of Electrical Engineering and Information Technology, Ostbayerische Technische Hochschule Regensburg, Regensburg, Germany
| | - Rudolf Fuchshofer
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
- *Correspondence: Rudolf Fuchshofer,
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Liesenborghs I, Schouten JS, Kutmon M, Gorgels TG, Evelo CT, Hubens WH, Beckers HJ, Webers CA, Eijssen LM. A systematically derived overview of the non-ubiquitous pathways and genes that define the molecular and genetic signature of the healthy trabecular meshwork. Genomics 2022; 114:110280. [DOI: 10.1016/j.ygeno.2022.110280] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 06/10/2021] [Accepted: 01/31/2022] [Indexed: 11/28/2022]
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12
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Alapati T, Sagal KM, Gudiseva HV, Pistilli M, Pyfer M, Chavali VRM, O’Brien JM. Evaluating TNF-α and Interleukin-2 (IL-2) Levels in African American Primary Open-Angle Glaucoma Patients. Genes (Basel) 2021; 13:genes13010054. [PMID: 35052396 PMCID: PMC8774833 DOI: 10.3390/genes13010054] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/19/2021] [Accepted: 12/23/2021] [Indexed: 12/30/2022] Open
Abstract
Purpose: To establish if SNPs in TNF-α and IL-2 genes are associated with Primary Open-Angle Glaucoma (POAG) in African Americans (AA). We also determined whether plasma TNF-α and IL-2 levels could serve as biomarkers for POAG in African Americans using sandwich enzyme-linked immunosorbent assay. Methods: A single SNP association analysis was performed to investigate the association between potential gene variants in TNF-α and IL-2 genes and POAG in the AA population. Plasma samples from 190 African Americans (72 from normal subjects and 118 POAG cases) were obtained for TNF- α studies and 367 samples (135 from normal subjects and 232 from POAG cases) were obtained for IL-2 studies. TNF-α levels and IL-2 levels were measured by sandwich enzyme-linked immunosorbent assays (ELISA) and analyzed to see if they reached significance in cases with POAG and endophenotypes when compared to normal subjects. Results: The SNP, rs1800630, in TNF-α gene was found to be marginally associated with POAG. SNPs in IL-2 gene were not associated with POAG in the case-control analysis. No significant difference was found between TNF-α levels and IL-2 levels in normal and POAG case subjects in our study. IL-2 levels were inversely correlated with high IOP in POAG cases. Conclusions: Although we found a marginal SNP association of TNF-α, assessing the expression levels of TNF-α and IL-2 may serve as promising biomarkers for African American POAG. Further investigation is needed to determine if POAG can be subdivided into more specified cohorts of the disease, which may affect plasma cytokine levels differently.
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Sanchez D, Ganfornina MD. The Lipocalin Apolipoprotein D Functional Portrait: A Systematic Review. Front Physiol 2021; 12:738991. [PMID: 34690812 PMCID: PMC8530192 DOI: 10.3389/fphys.2021.738991] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 08/30/2021] [Indexed: 12/18/2022] Open
Abstract
Apolipoprotein D is a chordate gene early originated in the Lipocalin protein family. Among other features, regulation of its expression in a wide variety of disease conditions in humans, as apparently unrelated as neurodegeneration or breast cancer, have called for attention on this gene. Also, its presence in different tissues, from blood to brain, and different subcellular locations, from HDL lipoparticles to the interior of lysosomes or the surface of extracellular vesicles, poses an interesting challenge in deciphering its physiological function: Is ApoD a moonlighting protein, serving different roles in different cellular compartments, tissues, or organisms? Or does it have a unique biochemical mechanism of action that accounts for such apparently diverse roles in different physiological situations? To answer these questions, we have performed a systematic review of all primary publications where ApoD properties have been investigated in chordates. We conclude that ApoD ligand binding in the Lipocalin pocket, combined with an antioxidant activity performed at the rim of the pocket are properties sufficient to explain ApoD association with different lipid-based structures, where its physiological function is better described as lipid-management than by long-range lipid-transport. Controlling the redox state of these lipid structures in particular subcellular locations or extracellular structures, ApoD is able to modulate an enormous array of apparently diverse processes in the organism, both in health and disease. The new picture emerging from these data should help to put the physiological role of ApoD in new contexts and to inspire well-focused future research.
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Affiliation(s)
- Diego Sanchez
- Instituto de Biologia y Genetica Molecular, Unidad de Excelencia, Universidad de Valladolid-Consejo Superior de Investigaciones Cientificas, Valladolid, Spain
| | - Maria D Ganfornina
- Instituto de Biologia y Genetica Molecular, Unidad de Excelencia, Universidad de Valladolid-Consejo Superior de Investigaciones Cientificas, Valladolid, Spain
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Fu Y, Luo L, Fan Y, Tang M. Downregulation of secreted protein acidic and rich in cysteine in human trabecular meshwork cells. Exp Ther Med 2021; 22:1126. [PMID: 34504578 PMCID: PMC8383334 DOI: 10.3892/etm.2021.10560] [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: 07/27/2020] [Accepted: 06/30/2021] [Indexed: 11/06/2022] Open
Abstract
Secreted protein acidic and rich in cysteine (SPARC) may play a notable role in aqueous humor outflow through the trabecular meshwork (TM). SPARC is a potential therapeutic target in glaucoma, and the mechanism by which it regulates intraocular pressure remains unclear. The present study aimed to observe the effects of SPARC in human TM cells (HTMCs) in vitro. SPARC was downregulated by recombinant lentiviral vectors in HTMCs, and the subsequent levels of F-actin expression, zonula occludens-1 (ZO-1) expression and cellular phagocytosis were observed and calculated. It was revealed that after 48 h of culture, the expression levels of SPARC, F-actin and ZO-1 were significantly decreased in the lentivirus group compared with those in the blank control and empty vector control groups. The downregulation of SPARC promoted phagocytosis in HTMCs after 24 or 48 h of culture. This indicated that the downregulation of SPARC decreased the expression levels of the cytoskeleton-associated proteins F-actin and ZO-1, promoted phagocytosis in HTMCs and may affect the outflow of aqueous humor via the TM pathway.
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Affiliation(s)
- Yang Fu
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200080, P.R. China.,Shanghai Key Laboratory of Fundus Disease, Shanghai General Hospital, Shanghai 200080, P.R. China
| | - Liying Luo
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200080, P.R. China.,Shanghai Key Laboratory of Fundus Disease, Shanghai General Hospital, Shanghai 200080, P.R. China
| | - Ying Fan
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200080, P.R. China.,Shanghai Key Laboratory of Fundus Disease, Shanghai General Hospital, Shanghai 200080, P.R. China
| | - Min Tang
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200080, P.R. China.,Shanghai Key Laboratory of Fundus Disease, Shanghai General Hospital, Shanghai 200080, P.R. China
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Johnstone M, Xin C, Tan J, Martin E, Wen J, Wang RK. Aqueous outflow regulation - 21st century concepts. Prog Retin Eye Res 2021; 83:100917. [PMID: 33217556 PMCID: PMC8126645 DOI: 10.1016/j.preteyeres.2020.100917] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 10/09/2020] [Accepted: 10/12/2020] [Indexed: 12/24/2022]
Abstract
We propose an integrated model of aqueous outflow control that employs a pump-conduit system in this article. Our model exploits accepted physiologic regulatory mechanisms such as those of the arterial, venous, and lymphatic systems. Here, we also provide a framework for developing novel diagnostic and therapeutic strategies to improve glaucoma patient care. In the model, the trabecular meshwork distends and recoils in response to continuous physiologic IOP transients like the ocular pulse, blinking, and eye movement. The elasticity of the trabecular meshwork determines cyclic volume changes in Schlemm's canal (SC). Tube-like SC inlet valves provide aqueous entry into the canal, and outlet valve leaflets at collector channels control aqueous exit from SC. Connections between the pressure-sensing trabecular meshwork and the outlet valve leaflets dynamically control flow from SC. Normal function requires regulation of the trabecular meshwork properties that determine distention and recoil. The aqueous pump-conduit provides short-term pressure control by varying stroke volume in response to pressure changes. Modulating TM constituents that regulate stroke volume provides long-term control. The aqueous outflow pump fails in glaucoma due to the loss of trabecular tissue elastance, as well as alterations in ciliary body tension. These processes lead to SC wall apposition and loss of motion. Visible evidence of pump failure includes a lack of pulsatile aqueous discharge into aqueous veins and reduced ability to reflux blood into SC. These alterations in the functional properties are challenging to monitor clinically. Phase-sensitive OCT now permits noninvasive, quantitative measurement of pulse-dependent TM motion in humans. This proposed conceptual model and related techniques offer a novel framework for understanding mechanisms, improving management, and development of therapeutic options for glaucoma.
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Affiliation(s)
| | - Chen Xin
- Department of Ophthalmology, Beijing Anzhen Hospital, Capital Medical University, China.
| | - James Tan
- Doheny Eye Institute and UCLA Department of Ophthalmology, USA.
| | | | | | - Ruikang K Wang
- Department of Ophthalmology, University of Washington, USA; Department of Bioengineering, University of Washington, USA.
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16
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Pouw AE, Greiner MA, Coussa RG, Jiao C, Han IC, Skeie JM, Fingert JH, Mullins RF, Sohn EH. Cell-Matrix Interactions in the Eye: From Cornea to Choroid. Cells 2021; 10:687. [PMID: 33804633 PMCID: PMC8003714 DOI: 10.3390/cells10030687] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 03/03/2021] [Accepted: 03/16/2021] [Indexed: 02/07/2023] Open
Abstract
The extracellular matrix (ECM) plays a crucial role in all parts of the eye, from maintaining clarity and hydration of the cornea and vitreous to regulating angiogenesis, intraocular pressure maintenance, and vascular signaling. This review focuses on the interactions of the ECM for homeostasis of normal physiologic functions of the cornea, vitreous, retina, retinal pigment epithelium, Bruch's membrane, and choroid as well as trabecular meshwork, optic nerve, conjunctiva and tenon's layer as it relates to glaucoma. A variety of pathways and key factors related to ECM in the eye are discussed, including but not limited to those related to transforming growth factor-β, vascular endothelial growth factor, basic-fibroblastic growth factor, connective tissue growth factor, matrix metalloproteinases (including MMP-2 and MMP-9, and MMP-14), collagen IV, fibronectin, elastin, canonical signaling, integrins, and endothelial morphogenesis consistent of cellular activation-tubulogenesis and cellular differentiation-stabilization. Alterations contributing to disease states such as wound healing, diabetes-related complications, Fuchs endothelial corneal dystrophy, angiogenesis, fibrosis, age-related macular degeneration, retinal detachment, and posteriorly inserted vitreous base are also reviewed.
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Affiliation(s)
- Andrew E. Pouw
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA; (A.E.P.); (M.A.G.); (R.G.C.); (C.J.); (I.C.H.); (J.M.S.); (J.H.F.); (R.F.M.)
- Institute for Vision Research, University of Iowa, Iowa City, IA 52242, USA
| | - Mark A. Greiner
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA; (A.E.P.); (M.A.G.); (R.G.C.); (C.J.); (I.C.H.); (J.M.S.); (J.H.F.); (R.F.M.)
- Institute for Vision Research, University of Iowa, Iowa City, IA 52242, USA
| | - Razek G. Coussa
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA; (A.E.P.); (M.A.G.); (R.G.C.); (C.J.); (I.C.H.); (J.M.S.); (J.H.F.); (R.F.M.)
- Institute for Vision Research, University of Iowa, Iowa City, IA 52242, USA
| | - Chunhua Jiao
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA; (A.E.P.); (M.A.G.); (R.G.C.); (C.J.); (I.C.H.); (J.M.S.); (J.H.F.); (R.F.M.)
- Institute for Vision Research, University of Iowa, Iowa City, IA 52242, USA
| | - Ian C. Han
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA; (A.E.P.); (M.A.G.); (R.G.C.); (C.J.); (I.C.H.); (J.M.S.); (J.H.F.); (R.F.M.)
- Institute for Vision Research, University of Iowa, Iowa City, IA 52242, USA
| | - Jessica M. Skeie
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA; (A.E.P.); (M.A.G.); (R.G.C.); (C.J.); (I.C.H.); (J.M.S.); (J.H.F.); (R.F.M.)
| | - John H. Fingert
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA; (A.E.P.); (M.A.G.); (R.G.C.); (C.J.); (I.C.H.); (J.M.S.); (J.H.F.); (R.F.M.)
- Institute for Vision Research, University of Iowa, Iowa City, IA 52242, USA
| | - Robert F. Mullins
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA; (A.E.P.); (M.A.G.); (R.G.C.); (C.J.); (I.C.H.); (J.M.S.); (J.H.F.); (R.F.M.)
- Institute for Vision Research, University of Iowa, Iowa City, IA 52242, USA
| | - Elliott H. Sohn
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA; (A.E.P.); (M.A.G.); (R.G.C.); (C.J.); (I.C.H.); (J.M.S.); (J.H.F.); (R.F.M.)
- Institute for Vision Research, University of Iowa, Iowa City, IA 52242, USA
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Dillinger AE, Kuespert S, Froemel F, Tamm ER, Fuchshofer R. CCN2/CTGF promotor activity in the developing and adult mouse eye. Cell Tissue Res 2021; 384:625-641. [PMID: 33512643 PMCID: PMC8211604 DOI: 10.1007/s00441-020-03332-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 10/29/2020] [Indexed: 12/23/2022]
Abstract
CCN2/CTGF is a matricellular protein that is known to enhance transforming growth factor-β signaling and to induce a myofibroblast-like phenotype in a variety of cell types. Here, we investigated Ccn2/Ctgf promotor activity during development and in the adult mouse eye, using CTGFLacZ/+ mice in which the β-galactosidase reporter gene LacZ had been inserted into the open reading frame of Ccn2/Ctgf. Promotor activity was assessed by staining for β-galactosidase activity and by immunolabeling using antibodies against β-galactosidase. Co-immunostaining using antibodies against glutamine synthetase, glial fibrillary acidic protein, choline acetyltransferase, and CD31 was applied to identify specific cell types. Ccn2/Ctgf promotor activity was intense in neural crest-derived cells differentiating to corneal stroma and endothelium, and to the stroma of choroid, iris, ciliary body, and the trabecular meshwork during development. In the adult eye, a persistent and very strong promotor activity was present in the trabecular meshwork outflow pathways. In addition, endothelial cells of Schlemm’s canal, and of retinal and choroidal vessels, retinal astrocytes, Müller glia, and starburst amacrine cells were stained. Very strong promoter activity was seen in the astrocytes of the glial lamina at the optic nerve head. We conclude that CCN2/CTGF signaling is involved in the processes that govern neural crest morphogenesis during ocular development. In the adult eye, CCN2/CTGF likely plays an important role for the trabecular meshwork outflow pathways and the glial lamina of the optic nerve head.
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Affiliation(s)
- Andrea E Dillinger
- Institute of Human Anatomy and Embryology, University of Regensburg, 93053, Regensburg, Germany
| | - Sabrina Kuespert
- Institute of Human Anatomy and Embryology, University of Regensburg, 93053, Regensburg, Germany
| | - Franziska Froemel
- Institute of Human Anatomy and Embryology, University of Regensburg, 93053, Regensburg, Germany
| | - Ernst R Tamm
- Institute of Human Anatomy and Embryology, University of Regensburg, 93053, Regensburg, Germany
| | - Rudolf Fuchshofer
- Institute of Human Anatomy and Embryology, University of Regensburg, 93053, Regensburg, Germany.
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18
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Secreted protein acidic and rich in cysteine (SPARC) knockout mice have greater outflow facility. PLoS One 2020; 15:e0241294. [PMID: 33147244 PMCID: PMC7641442 DOI: 10.1371/journal.pone.0241294] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 10/12/2020] [Indexed: 11/24/2022] Open
Abstract
Purpose Secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein that regulates intraocular pressure (IOP) by altering extracellular matrix (ECM) homeostasis within the trabecular meshwork (TM). We hypothesized that the lower IOP previously observed in SPARC -/- mice is due to a greater outflow facility. Methods Mouse outflow facility (Clive) was determined by multiple flow rate infusion, and episcleral venous pressure (Pe) was estimated by manometry. The animals were then euthanized, eliminating aqueous formation rate (Fin) and Pe. The C value was determined again (Cdead) while Fin was reduced to zero. Additional mice were euthanized for immunohistochemistry to analyze ECM components of the TM. Results The Clive and Cdead of SPARC -/- mice were 0.014 ± 0.002 μL/min/mmHg and 0.015 ± 0.002 μL/min/mmHg, respectively (p = 0.376, N/S). Compared to the Clive = 0.010 ± 0.002 μL/min/mmHg and Cdead = 0.011 ± 0.002 μL/min/mmHg in the WT mice (p = 0.548, N/S), the Clive and Cdead values for the SPARC -/- mice were higher. Pe values were estimated to be 8.0 ± 0.2 mmHg and 8.3 ± 0.7 mmHg in SPARC -/- and WT mice, respectively (p = 0.304, N/S). Uveoscleral outflow (Fu) was 0.019 ± 0.007 μL/min and 0.022 ± 0.006 μL/min for SPARC -/- and WT mice, respectively (p = 0.561, N/S). Fin was 0.114 ± 0.002 μL/min and 0.120 ± 0.016 μL/min for SPARC -/- and WT mice (p = 0.591, N/S). Immunohistochemistry demonstrated decreases of collagen types IV and VI, fibronectin, laminin, PAI-1, and tenascin-C within the TM of SPARC -/- mice (p < 0.05). Conclusions The lower IOP of SPARC -/- mice is due to greater aqueous humor outflow facility through the conventional pathway. Corresponding changes in several matricellular proteins and ECM structural components were noted in the TM of SPARC -/- mice.
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19
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Borrás T, Cowley DO, Asokan P, Pandya K. Generation of a Matrix Gla (Mgp) floxed mouse, followed by conditional knockout, uncovers a new Mgp function in the eye. Sci Rep 2020; 10:18583. [PMID: 33122788 PMCID: PMC7596545 DOI: 10.1038/s41598-020-75031-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 10/09/2020] [Indexed: 01/07/2023] Open
Abstract
The ability to ablate a gene in a given tissue by generating a conditional knockout (cKO) is crucial for determining its function in the targeted tissue. Such tissue-specific ablation is even more critical when the gene's conventional knockout (KO) is lethal, which precludes studying the consequences of its deletion in other tissues. Therefore, here we describe a successful strategy that generated a Matrix Gla floxed mouse (Mgp.floxed) by the CRISPR/Cas9 system, that subsequently allowed the generation of cKOs by local viral delivery of the Cre-recombinase enzyme. MGP is a well-established inhibitor of calcification gene, highly expressed in arteries' smooth muscle cells and chondrocytes. MGP is also one of the most abundant genes in the trabecular meshwork, the eye tissue responsible for maintenance of intraocular pressure (IOP) and development of Glaucoma. Our strategy entailed one-step injection of two gRNAs, Cas9 protein and a long-single-stranded-circular DNA donor vector (lsscDNA, 6.7 kb) containing two loxP sites in cis and 900-700 bp 5'/3' homology arms. Ocular intracameral injection of Mgp.floxed mice with a Cre-adenovirus, led to an Mgp.TMcKO mouse which developed elevated IOP. Our study discovered a new role for the Mgp gene as a keeper of physiological IOP in the eye.
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Affiliation(s)
- Teresa Borrás
- Department of Ophthalmology, University of North Carolina School of Medicine, 4109C Neuroscience Research Building CB 7041, 115 Mason Farm Road, Chapel Hill, NC, 27599-7041, USA.
| | - Dale O Cowley
- Animal Models Core, University of North Carolina, Chapel Hill, NC, USA
| | - Priyadarsini Asokan
- Department of Ophthalmology, University of North Carolina School of Medicine, 4109C Neuroscience Research Building CB 7041, 115 Mason Farm Road, Chapel Hill, NC, 27599-7041, USA
| | - Kumar Pandya
- Animal Models Core, University of North Carolina, Chapel Hill, NC, USA
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Vernazza S, Tirendi S, Bassi AM, Traverso CE, Saccà SC. Neuroinflammation in Primary Open-Angle Glaucoma. J Clin Med 2020; 9:E3172. [PMID: 33007927 PMCID: PMC7601106 DOI: 10.3390/jcm9103172] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/24/2020] [Accepted: 09/28/2020] [Indexed: 12/18/2022] Open
Abstract
Primary open-angle glaucoma (POAG) is the second leading cause of irreversible blindness worldwide. Increasing evidence suggests oxidative damage and immune response defects are key factors contributing to glaucoma onset. Indeed, both the failure of the trabecular meshwork tissue in the conventional outflow pathway and the neuroinflammation process, which drives the neurodegeneration, seem to be linked to the age-related over-production of free radicals (i.e., mitochondrial dysfunction) and to oxidative stress-linked immunostimulatory signaling. Several previous studies have described a wide range of oxidative stress-related makers which are found in glaucomatous patients, including low levels of antioxidant defences, dysfunction/activation of glial cells, the activation of the NF-κB pathway and the up-regulation of pro-inflammatory cytokines, and so on. However, the intraocular pressure is still currently the only risk factor modifiable by medication or glaucoma surgery. This present review aims to summarize the multiple cellular processes, which promote different risk factors in glaucoma including aging, oxidative stress, trabecular meshwork defects, glial activation response, neurodegenerative insults, and the altered regulation of immune response.
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Affiliation(s)
| | - Sara Tirendi
- Department of Experimental Medicine (DIMES), University of Genoa, 16132 Genoa, Italy; (S.T.); (A.M.B.)
- Inter-University Center for the Promotion of the 3Rs Principles in Teaching & Research (Centro 3R), Italy
| | - Anna Maria Bassi
- Department of Experimental Medicine (DIMES), University of Genoa, 16132 Genoa, Italy; (S.T.); (A.M.B.)
- Inter-University Center for the Promotion of the 3Rs Principles in Teaching & Research (Centro 3R), Italy
| | - Carlo Enrico Traverso
- Clinica Oculistica, DiNOGMI, University of Genoa, 16132 Genoa, Italy;
- Ophthalmology Unit, IRCCS-Polyclinic San Martino Hospital, 16132 Genoa, Italy;
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Molecular taxonomy of human ocular outflow tissues defined by single-cell transcriptomics. Proc Natl Acad Sci U S A 2020; 117:12856-12867. [PMID: 32439707 PMCID: PMC7293718 DOI: 10.1073/pnas.2001896117] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Ocular hypertension is the primary and only modifiable risk factor for glaucoma, the leading cause of irreversible blindness. Intraocular pressure is regulated homeostatically by resistance to aqueous humor outflow through an architecturally complex tissue, the conventional/trabecular pathway. In this study, we generated a comprehensive cell atlas of the human trabecular meshwork and neighboring tissues using single-cell RNA sequencing. We identified 12 distinct cell types and mapped region-specific expression of candidate genes. The utility of our atlas was demonstrated by mapping glaucoma-relevant genes to conventional outflow cell types. Our study provides a comprehensive molecular and cellular classification of tissue structures responsible for intraocular pressure homeostasis in health and dysregulation in disease. The conventional outflow pathway is a complex tissue responsible for maintaining intraocular pressure (IOP) homeostasis. The coordinated effort of multiple cells with differing responsibilities ensures healthy outflow function and IOP maintenance. Dysfunction of one or more resident cell types results in ocular hypertension and risk for glaucoma, a leading cause of blindness. In this study, single-cell RNA sequencing was performed to generate a comprehensive cell atlas of human conventional outflow tissues. We obtained expression profiles of 17,757 genes from 8,758 cells from eight eyes of human donors representing the outflow cell transcriptome. Upon clustering analysis, 12 distinct cell types were identified, and region-specific expression of candidate genes was mapped in human tissues. Significantly, we identified two distinct expression patterns (myofibroblast- and fibroblast-like) from cells located in the trabecular meshwork (TM), the primary structural component of the conventional outflow pathway. We also located Schwann cell and macrophage signatures in the TM. The second primary component structure, Schlemm’s canal, displayed a unique combination of lymphatic/blood vascular gene expression. Other expression clusters corresponded to cells from neighboring tissues, predominantly in the ciliary muscle/scleral spur, which together correspond to the uveoscleral outflow pathway. Importantly, the utility of our atlas was demonstrated by mapping glaucoma-relevant genes to outflow cell clusters. Our study provides a comprehensive molecular and cellular classification of conventional and unconventional outflow pathway structures responsible for IOP homeostasis.
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Mocan MC, Mehta AA, Aref AA. Update in Genetics and Surgical Management of
Primary Congenital Glaucoma. Turk J Ophthalmol 2019; 49:347-355. [PMID: 31893591 PMCID: PMC6961078 DOI: 10.4274/tjo.galenos.2019.28828] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 06/10/2019] [Indexed: 02/07/2023] Open
Abstract
Primary congenital glaucoma (PCG) continues to be an important cause of visual impairment in children despite advances in medical and surgical treatment options. The progressive and blinding nature of the disease, together with the long lifespan of the affected population, necessitates a thorough understanding of the pathophysiology of PCG and the development of long-lasting treatment options. The first part of this review discusses the genetic features and makeup of this disorder, including all currently identified genetic loci (GLC3A, GLC3B, GLC3C and GLC3D) and relevant protein targets important for trabecular and Schlemm canal dysgenesis. These target molecules primarily include CYP1B1, LTBP2, and TEK/Tie2 proteins. Their potential roles in PCG pathogenesis are discussed with the purpose of bringing the readers up to date on the molecular genetics aspect of this disorder. Special emphasis is placed on functional implications of reported genetic mutations in the setting of PCG. The second part of the review focuses on various modifications and refinements to the traditional surgical approaches performed to treat PCG, including advances in goniotomy and trabeculotomy ab externo techniques, glaucoma drainage implant surgery and cyclodiode photocoagulation techniques that ultimately provide safer surgical approaches and more effective intraocular pressure control in the 21st century.
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Affiliation(s)
- Mehmet C. Mocan
- University of Illinois at Chicago, Department of Ophthalmology and Visual Sciences, Chicago, USA
| | - Amy A. Mehta
- University of Illinois at Chicago, Department of Ophthalmology and Visual Sciences, Chicago, USA
| | - Ahmad A. Aref
- University of Illinois at Chicago, Department of Ophthalmology and Visual Sciences, Chicago, USA
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Faralli JA, Filla MS, Peters DM. Role of Fibronectin in Primary Open Angle Glaucoma. Cells 2019; 8:E1518. [PMID: 31779192 PMCID: PMC6953041 DOI: 10.3390/cells8121518] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 11/22/2019] [Accepted: 11/24/2019] [Indexed: 01/08/2023] Open
Abstract
Primary open angle glaucoma (POAG) is the most common form of glaucoma and the 2nd most common cause of irreversible vision loss in the United States. Nearly 67 million people have the disease worldwide including >3 million in the United States. A major risk factor for POAG is an elevation in intraocular pressure (IOP). The increase in IOP is believed to be caused by an increase in the deposition of extracellular matrix proteins, in particular fibronectin, in a region of the eye known as the trabecular meshwork (TM). How fibronectin contributes to the increase in IOP is not well understood. The increased density of fibronectin fibrils is thought to increase IOP by altering the compliance of the trabecular meshwork. Recent studies, however, also suggest that the composition and organization of fibronectin fibrils would affect IOP by changing the cell-matrix signaling events that control the functional properties of the cells in the trabecular meshwork. In this article, we will discuss how changes in the properties of fibronectin and fibronectin fibrils could contribute to the regulation of IOP.
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Affiliation(s)
- Jennifer A. Faralli
- Departments of Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53706, USA; (J.A.F.); (M.S.F.)
| | - Mark S. Filla
- Departments of Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53706, USA; (J.A.F.); (M.S.F.)
| | - Donna M. Peters
- Departments of Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53706, USA; (J.A.F.); (M.S.F.)
- Ophthalmology & Visual Sciences, University of Wisconsin, Madison, WI 53706, USA
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Ragg S, Key M, Rankin F, WuDunn D. The Effect of Molecular Weight on Passage of Proteins Through the Blood-Aqueous Barrier. Invest Ophthalmol Vis Sci 2019; 60:1461-1469. [PMID: 30951588 DOI: 10.1167/iovs.19-26542] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To determine the effect of molecular weight (MW) on the concentration of plasma-derived proteins in aqueous humor and to estimate the plasma-derived and eye-derived fractions for each protein. Methods Aqueous humor and plasma samples were obtained during cataract surgery on an institutional review board-approved protocol. Protein concentrations were determined by ELISA and quantitative antibody microarrays. A total of 93 proteins were studied, with most proteins analyzed using 27 to 116 aqueous and 6 to 30 plasma samples. Results Plasma proteins without evidence of intraocular expression by sequence tags were used to fit a logarithmic model relating aqueous-plasma ratio (AH:PL) to MW. The log(AH:PL) appears to be well predicted by the log(MW) (P < 0.0001), with smaller proteins such as cystatin C (13 kDa) having a higher AH:PL (1:6) than larger proteins such as albumin (66 kDa, 1:300) and complement component 5 (188 kDa, 1:2500). The logarithmic model was used to calculate the eye-derived intraocular fraction (IOF) for each protein. Based on the IOF, 66 proteins could be categorized as plasma-derived (IOF<20), whereas 10 proteins were primarily derived from eye tissue (IOF >80), and 17 proteins had contribution from both plasma and eye tissue (IOF 20-80). Conclusions Protein concentration of plasma-derived proteins in aqueous is nonlinearly dependent on MW in favor of smaller proteins. Our study demonstrates that for proper interpretation of results, proteomic studies evaluating changes in aqueous humor protein levels should take into account the plasma and eye-derived fractions.
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Affiliation(s)
- Susanne Ragg
- Department of Pediatrics, University of Florida College of Medicine-Jacksonville, Jacksonville, Florida, United States.,Center for Computational Diagnostics, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Melissa Key
- Department of Biostatistics, Fairbanks School of Public Health, Indiana University Purdue University Indianapolis, Indianapolis, Indiana, United States
| | - Fernanda Rankin
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Darrell WuDunn
- Department of Ophthalmology, University of Florida College of Medicine-Jacksonville, Jacksonville, Florida, United States.,Department of Ophthalmology, Glick Eye Institute, Indiana University School of Medicine, Indianapolis, Indiana, United States
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25
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Boldinova EO, Khairullin RF, Makarova AV, Zharkov DO. Isoforms of Base Excision Repair Enzymes Produced by Alternative Splicing. Int J Mol Sci 2019; 20:ijms20133279. [PMID: 31277343 PMCID: PMC6651865 DOI: 10.3390/ijms20133279] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 06/29/2019] [Accepted: 07/02/2019] [Indexed: 02/07/2023] Open
Abstract
Transcripts of many enzymes involved in base excision repair (BER) undergo extensive alternative splicing, but functions of the corresponding alternative splice variants remain largely unexplored. In this review, we cover the studies describing the common alternatively spliced isoforms and disease-associated variants of DNA glycosylases, AP-endonuclease 1, and DNA polymerase beta. We also discuss the roles of alternative splicing in the regulation of their expression, catalytic activities, and intracellular transport.
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Affiliation(s)
| | - Rafil F Khairullin
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 9 Parizhskoy Kommuny Str., 420012 Kazan, Russia
| | - Alena V Makarova
- RAS Institute of Molecular Genetics, 2 Kurchatova Sq., 123182 Moscow, Russia.
| | - Dmitry O Zharkov
- Novosibirsk State University, 1 Pirogova St., 630090 Novosibirsk, Russia.
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia.
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26
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Impact of pigment dispersion on trabecular meshwork cells. Graefes Arch Clin Exp Ophthalmol 2019; 257:1217-1230. [PMID: 30919079 DOI: 10.1007/s00417-019-04300-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 10/22/2018] [Accepted: 11/29/2018] [Indexed: 12/11/2022] Open
Abstract
PURPOSE Dysfunction of the trabecular meshwork (TM) in pigmentary glaucoma contributes to increased aqueous humor outflow resistance and intraocular pressure. In this study, we investigated the effect of pigment dispersion on trabecular meshwork cells. METHODS Porcine TM cells from ab interno trabeculectomy specimens were exposed to pigment dispersion, then, analyzed for changes in morphology, immunostaining, and ultrastructure. Their abilities to phagocytose migrate, and contraction was quantified. An expression microarray, using 23,937 probes, and a pathway analysis were performed. RESULTS Stress fiber formation was increased in the pigment dispersion group (P) (60.1 ± 0.3%, n = 10) compared to control (C) (38.4 ± 2.5%, n = 11, p < 0.001). Phagocytosis declined (number of cells with microspheres in P = 37.0 ± 1.1% and in C = 68.7 ± 1.3%, n = 3, p < 0.001) and migration was reduced after 6 h (cells within the visual field over 6 h in P = 28.0.1 ± 2.3 (n = 12) and in C = 40.6 ± 3.3 (n = 13), p < 0.01). Pigment induced contraction at 24 h onwards (p < 0.01). Microarray analysis revealed that Rho signaling was central to these responses. CONCLUSION Exposure of TM cells to pigment dispersion resulted in reduced phagocytosis and migration, as well as increased stress fiber formation and cell contraction. The Rho signaling pathway played a central and early role, suggesting that its inhibitors could be used as a specific intervention in treatment of pigmentary glaucoma.
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27
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Pugh CA, Farrell LL, Carlisle AJ, Bush SJ, Ewing A, Trejo-Reveles V, Matika O, de Kloet A, Walsh C, Bishop SC, Prendergast JGD, Rainger J, Schoenebeck JJ, Summers KM. Arginine to Glutamine Variant in Olfactomedin Like 3 ( OLFML3) Is a Candidate for Severe Goniodysgenesis and Glaucoma in the Border Collie Dog Breed. G3 (BETHESDA, MD.) 2019; 9:943-954. [PMID: 30696701 PMCID: PMC6404605 DOI: 10.1534/g3.118.200944] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 01/19/2019] [Indexed: 12/23/2022]
Abstract
Goniodysgenesis is a developmental abnormality of the anterior chamber of the eye. It is generally considered to be congenital in dogs (Canis lupus familiaris), and has been associated with glaucoma and blindness. Goniodysgenesis and early-onset glaucoma initially emerged in Border Collies in Australia in the late 1990s and have subsequently been found in this breed in Europe and the USA. The objective of the present study was to determine the genetic basis of goniodysgenesis in Border Collies. Clinical diagnosis was based on results of examinations by veterinary ophthalmologists of affected and unaffected dogs from eleven different countries. Genotyping using the Illumina high density canine single nucleotide variant genotyping chip was used to identify a candidate genetic region. There was a highly significant peak of association over chromosome 17, with a p-value of 2 × 10-13 Expression profiles and evolutionary conservation of candidate genes were assessed using public databases. Whole genome sequences of three dogs with glaucoma, three severely affected by goniodysgenesis and three unaffected dogs identified a missense variant in the olfactomedin like 3 (OLFML3) gene in all six affected animals. This was homozygous for the risk allele in all nine cases with glaucoma and 12 of 14 other severely affected animals. Of 67 reportedly unaffected animals, only one was homozygous for this variant (offspring of parents both with goniodysgenesis who were also homozygous for the variant). Analysis of pedigree information was consistent with an autosomal recessive mode of inheritance for severe goniodysgenesis (potentially leading to glaucoma) in this breed. The identification of a candidate genetic region and putative causative variant will aid breeders to reduce the frequency of goniodysgenesis and the risk of glaucoma in the Border Collie population.
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Affiliation(s)
- Carys A Pugh
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
| | - Lindsay L Farrell
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
| | - Ailsa J Carlisle
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
| | - Stephen J Bush
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
- Nuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, United Kingdom
| | - Adam Ewing
- Mater Research Institute-University of Queensland, Translational Research Institute, Brisbane, Qld 4102, Australia
| | - Violeta Trejo-Reveles
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
| | - Oswald Matika
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
| | - Arne de Kloet
- Animal Genetics, 1336 Timberlane Rd, Tallahassee, FL 32312
| | - Caitlin Walsh
- Animal Genetics, 1336 Timberlane Rd, Tallahassee, FL 32312
| | - Stephen C Bishop
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
| | - James G D Prendergast
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
| | - Joe Rainger
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
| | - Jeffrey J Schoenebeck
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
| | - Kim M Summers
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Easter Bush, EH25 9RG, United Kingdom
- Mater Research Institute-University of Queensland, Translational Research Institute, Brisbane, Qld 4102, Australia
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Multiomic Signature of Glaucoma Predisposition in Flammer Syndrome Affected Individuals – Innovative Predictive, Preventive and Personalised Strategies in Disease Management. FLAMMER SYNDROME 2019. [DOI: 10.1007/978-3-030-13550-8_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Sutherland C, Wang Y, Brown RV, Foley J, Mahler B, Janardhan KS, Kovi RC, Jetten AM. Laser Capture Microdissection of Highly Pure Trabecular Meshwork from Mouse Eyes for Gene Expression Analysis. J Vis Exp 2018. [PMID: 29912187 DOI: 10.3791/57576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Abstract
Laser capture microdissection (LCM) has allowed gene expression analysis of single cells and enriched cell populations in tissue sections. LCM is a great tool for the study of the molecular mechanisms underlying cell differentiation and the development and progression of various diseases, including glaucoma. Glaucoma, which comprises a family of progressive optic neuropathies, is the most common cause of irreversible blindness worldwide. Structural changes and damage within the trabecular meshwork (TM) can result in increased intraocular pressure (IOP), which is a major risk factor for developing glaucoma. However, the precise molecular mechanisms involved are still poorly understood. The ability to perform gene expression analysis will be crucial in obtaining further insights into the function of these cells and its role in the regulation of IOP and glaucoma development. To achieve this, a reproducible method for isolating highly enriched TM from frozen sections of mouse eyes and a method for downstream gene expression analysis, such as RT-qPCR and RNA-Seq is needed. The method described herein is developed to isolate highly pure TM from mouse eyes for downstream digital PCR and microarray analysis. In addition, this technique can be easily adapted for the isolation of other highly enriched ocular cells and cell compartments that have been difficult to isolate from mouse eyes. The combination of LCM and RNA analysis can contribute to a more comprehensive understanding of the cellular events underlying glaucoma.
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Affiliation(s)
- Caleb Sutherland
- Immunity, Inflammation, and Disease Laboratory, Division of Intramural Research, National Institute of Environmental Health Sciences, NIH
| | - Yu Wang
- Cellular and Molecular Pathology Branch, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, NIH
| | - Robert V Brown
- Immunity, Inflammation, and Disease Laboratory, Division of Intramural Research, National Institute of Environmental Health Sciences, NIH
| | - Julie Foley
- Cellular and Molecular Pathology Branch, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, NIH
| | - Beth Mahler
- Cellular and Molecular Pathology Branch, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, NIH
| | - Kyathanahalli S Janardhan
- Cellular and Molecular Pathology Branch, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, NIH; Integrated Laboratory Systems Inc
| | - Ramesh C Kovi
- Cellular and Molecular Pathology Branch, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, NIH; Experimental Pathology Laboratories Inc
| | - Anton M Jetten
- Immunity, Inflammation, and Disease Laboratory, Division of Intramural Research, National Institute of Environmental Health Sciences, NIH;
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30
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Seleem AA, Sultan ARS, Said A, Shahat MM, Moustafa MA. Localization of connective tissue growth factor (CTGF) and transforming growth factor beta-2 (TGF-β2) during eye development of four species of birds. J Histotechnol 2018. [DOI: 10.1080/01478885.2018.1475861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Amin A. Seleem
- Biology Department, Faculty of Science and Arts, Taibah University, Allula, Kingdom of Saudi Arabia
- Zoology Department, Faculty of Science, Sohag University, Sohag, Egypt
| | | | - Ahmed Said
- Zoology Department, Faculty of Science, Al-Azhar University, Assiut, Egypt
| | - Mohamed M. Shahat
- Zoology Department, Faculty of Science, Al-Azhar University, Assiut, Egypt
| | - Mohsen A. Moustafa
- Zoology Department, Faculty of Science, Al-Azhar University, Assiut, Egypt
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31
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Dang Y, Waxman S, Wang C, Loewen RT, Sun M, Loewen NA. A porcine ex vivo model of pigmentary glaucoma. Sci Rep 2018; 8:5468. [PMID: 29615741 PMCID: PMC5882895 DOI: 10.1038/s41598-018-23861-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 03/16/2018] [Indexed: 11/11/2022] Open
Abstract
Pigment dispersion can lead to pigmentary glaucoma, a poorly understood condition of younger myopic eyes with fluctuating high intraocular pressure. It has been difficult to investigate its pathogenesis without a model similar to human eyes in size and behavior. Here we present a porcine ex vivo model that recreates several features of pigmentary glaucoma, including intraocular hypertension, accumulation of pigment in the trabecular meshwork, and declining phagocytosis. We found that trabecular meshwork cells regulate outflow, form actin stress fibers, and have a decreased phagocytic activity. Gene expression microarrays and a pathway analysis of TM monolayers as well as ex vivo anterior segment perfusion cultures indicated that RhoA plays a central role in regulating the cytoskeleton, motility, and phagocytosis in the trabecular meshwork, providing new insights and targets to investigate in pigmentary glaucoma.
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Affiliation(s)
- Yalong Dang
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, United States of America
| | - Susannah Waxman
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, United States of America
| | - Chao Wang
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, United States of America
- Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
| | - Ralitsa T Loewen
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, United States of America
| | - Ming Sun
- Department of Cell Biology, School of Medicine, University of Pittsburgh, Pittsburgh, United States of America
| | - Nils A Loewen
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, United States of America.
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32
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Gharahkhani P, Burdon KP, Cooke Bailey JN, Hewitt AW, Law MH, Pasquale LR, Kang JH, Haines JL, Souzeau E, Zhou T, Siggs OM, Landers J, Awadalla M, Sharma S, Mills RA, Ridge B, Lynn D, Casson R, Graham SL, Goldberg I, White A, Healey PR, Grigg J, Lawlor M, Mitchell P, Ruddle J, Coote M, Walland M, Best S, Vincent A, Gale J, RadfordSmith G, Whiteman DC, Montgomery GW, Martin NG, Mackey DA, Wiggs JL, MacGregor S, Craig JE. Analysis combining correlated glaucoma traits identifies five new risk loci for open-angle glaucoma. Sci Rep 2018; 8:3124. [PMID: 29449654 PMCID: PMC5814451 DOI: 10.1038/s41598-018-20435-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 01/18/2018] [Indexed: 01/08/2023] Open
Abstract
Open-angle glaucoma (OAG) is a major cause of blindness worldwide. To identify new risk loci for OAG, we performed a genome-wide association study in 3,071 OAG cases and 6,750 unscreened controls, and meta-analysed the results with GWAS data for intraocular pressure (IOP) and optic disc parameters (the overall meta-analysis sample size varying between 32,000 to 48,000 participants), which are glaucoma-related traits. We identified and independently validated four novel genome-wide significant associations within or near MYOF and CYP26A1, LINC02052 and CRYGS, LMX1B, and LMO7 using single variant tests, one additional locus (C9) using gene-based tests, and two genetic pathways - "response to fluid shear stress" and "abnormal retina morphology" - in pathway-based tests. Interestingly, some of the new risk loci contribute to risk of other genetically-correlated eye diseases including myopia and age-related macular degeneration. To our knowledge, this study is the first integrative study to combine genetic data from OAG and its correlated traits to identify new risk variants and genetic pathways, highlighting the future potential of combining genetic data from genetically-correlated eye traits for the purpose of gene discovery and mapping.
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Affiliation(s)
- Puya Gharahkhani
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia.
| | | | - Jessica N Cooke Bailey
- Population and Quantitative Health Sciences, Institute for Computational Biology, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | | | - Matthew H Law
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Louis R Pasquale
- Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, MA, USA.,Channing Division of Network Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Jae H Kang
- Channing Division of Network Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Jonathan L Haines
- Population and Quantitative Health Sciences, Institute for Computational Biology, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Emmanuelle Souzeau
- Department of Ophthalmology, Flinders University, Adelaide, South Australia, Australia
| | - Tiger Zhou
- Department of Ophthalmology, Flinders University, Adelaide, South Australia, Australia
| | - Owen M Siggs
- Department of Ophthalmology, Flinders University, Adelaide, South Australia, Australia
| | - John Landers
- Department of Ophthalmology, Flinders University, Adelaide, South Australia, Australia
| | - Mona Awadalla
- Department of Ophthalmology, Flinders University, Adelaide, South Australia, Australia
| | - Shiwani Sharma
- Department of Ophthalmology, Flinders University, Adelaide, South Australia, Australia
| | - Richard A Mills
- Department of Ophthalmology, Flinders University, Adelaide, South Australia, Australia
| | - Bronwyn Ridge
- Department of Ophthalmology, Flinders University, Adelaide, South Australia, Australia
| | - David Lynn
- South Australian Health & Medical Research Institute, School of Medicine, Flinders University, Adelaide, South Australia, Australia
| | - Robert Casson
- South Australian Institute of Ophthalmology, University of Adelaide, Adelaide, South Australia, Australia
| | - Stuart L Graham
- Ophthalmology and Vision Science, Macquarie University, Sydney, New South Wales, Australia
| | - Ivan Goldberg
- Department of Ophthalmology, University of Sydney, Sydney, Australia
| | - Andrew White
- Department of Ophthalmology, University of Sydney, Sydney, Australia.,Centre for Vision Research, The Westmead Institute for Medical Research, University of Sydney, Westmead, NSW, Australia
| | - Paul R Healey
- Department of Ophthalmology, University of Sydney, Sydney, Australia.,Centre for Vision Research, The Westmead Institute for Medical Research, University of Sydney, Westmead, NSW, Australia
| | - John Grigg
- Department of Ophthalmology, University of Sydney, Sydney, Australia
| | - Mitchell Lawlor
- Department of Ophthalmology, University of Sydney, Sydney, Australia
| | - Paul Mitchell
- Centre for Vision Research, The Westmead Institute for Medical Research, University of Sydney, Westmead, NSW, Australia
| | - Jonathan Ruddle
- Centre for Eye Research Australia (CERA), University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Michael Coote
- Centre for Eye Research Australia (CERA), University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Mark Walland
- Centre for Eye Research Australia (CERA), University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Stephen Best
- Department of Ophthalmology, University of Auckland, Auckland, New Zealand
| | - Andrea Vincent
- Department of Ophthalmology, University of Auckland, Auckland, New Zealand
| | - Jesse Gale
- Department of Ophthalmology, University of Otago, Dunedin, Otago, New Zealand
| | - Graham RadfordSmith
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia.,School of Medicine, University of Queensland, Herston Campus, Brisbane, QLD, Australia
| | - David C Whiteman
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Grant W Montgomery
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia.,Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Nicholas G Martin
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - David A Mackey
- University of Tasmania, Hobart, Tasmania, Australia.,Centre for Ophthalmology and Visual Science, Lions Eye Institute, University of Western Australia, Perth, Australia
| | - Janey L Wiggs
- Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, MA, USA
| | - Stuart MacGregor
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Jamie E Craig
- Department of Ophthalmology, Flinders University, Adelaide, South Australia, Australia.
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Abstract
Transforming growth factor-β (TGF-β) may play a role in the pathogenesis of primary open-angle glaucoma (POAG). Elevated levels of TGF-β are found in the aqueous humor and in reactive optic nerve astrocytes in patients with glaucoma. In POAG, aqueous humor outflow resistance at the trabecular meshwork (TM) leads to increased intraocular pressure and retinal ganglion cell death. It is hypothesized that TGF-β increases outflow resistance by altering extracellular matrix homeostasis and cell contractility in the TM through interactions with other proteins and signaling molecules. TGF-β may also be involved in damage to the optic nerve head. Current available therapies for POAG focus exclusively on lowering intraocular pressure without addressing extracellular matrix homeostasis processes in the TM. The purpose of this review is to discuss possible therapeutic strategies targeting TGF-β in the treatment of POAG. Herein, we describe the current understanding of the role of TGF-β in POAG pathophysiology, and examine ways TGF-β may be targeted at the levels of production, activation, downstream signaling, and homeostatic regulation.
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Montecchi-Palmer M, Bermudez JY, Webber HC, Patel GC, Clark AF, Mao W. TGFβ2 Induces the Formation of Cross-Linked Actin Networks (CLANs) in Human Trabecular Meshwork Cells Through the Smad and Non-Smad Dependent Pathways. Invest Ophthalmol Vis Sci 2017; 58:1288-1295. [PMID: 28241317 PMCID: PMC5341625 DOI: 10.1167/iovs.16-19672] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Purpose Increased intraocular pressure results from increased aqueous humor (AH) outflow resistance at the trabecular meshwork (TM) due to pathologic changes including the formation of cross-linked actin networks (CLANs). Transforming growth factor β2 (TGFβ2) is elevated in the AH and TM of primary open angle glaucoma (POAG) patients and induces POAG-associated TM changes, including CLANs. We determined the role of individual TGFβ2 signaling pathways in CLAN formation. Methods Cultured nonglaucomatous human TM (NTM) cells were treated with control or TGFβ2, with or without the inhibitors of TGFβ receptor, Smad3, c-Jun N-terminal kinases (JNK), extracellular signal regulated kinase (ERK), P38, or Rho-associated protein kinase (ROCK). NTM cells were cotreated with TGFβ2 plus inhibitors for 10 days or pretreated with TGFβ2 for 10 days followed by 1-hour inhibitor treatment. NTM cells were immunostained with phalloidin-Alexa-488 and 4',6-diamidino-2-phenylindole (DAPI). Data were analyzed using 1-way ANOVA and Dunnett's post hoc test. Results TGFβ2 significantly induced CLAN formation (n = 6 to 12, P < 0.05), which was completely inhibited by TGFβ receptor, Smad3, and ERK inhibitors, as well as completely or partially inhibited by JNK, P38, and ROCK inhibitors, depending on cell strains. One-hour exposure to ROCK inhibitor completely resolved formed CLANs (P < 0.05), whereas TGFβ receptor, Smad3 inhibitor, and ERK inhibitors resulted in partial or complete resolution. The JNK and P38 inhibitors showed partial or no resolution. Among these inhibitors, the ROCK inhibitor was the most disruptive to the actin stress fibers, whereas ERK inhibition showed the least disruption. Conclusions TGFβ2-induced CLANs in NTM cells were prevented and resolved using various pathway inhibitors. Apart from CLAN inhibition, some of these inhibitors also had different effects on actin stress fibers.
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Affiliation(s)
- Michela Montecchi-Palmer
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Jaclyn Y Bermudez
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Hannah C Webber
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Gaurang C Patel
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Abbot F Clark
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Weiming Mao
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
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35
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Sathiyanathan P, Tay CY, Stanton LW. Transcriptome analysis for the identification of cellular markers related to trabecular meshwork differentiation. BMC Genomics 2017; 18:383. [PMID: 28514956 PMCID: PMC5436446 DOI: 10.1186/s12864-017-3758-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 05/03/2017] [Indexed: 12/20/2022] Open
Abstract
Background Development of primary open-angle glaucoma (POAG) is associated with the malfunctioning trabecular meshwork (TM). Cell therapy offers great potential for the treatment of POAG, but requires the generation of functional TM cells in vitro to replace the lost/dysfunctional cells. TM differentiation in vitro from various stem cell types must be monitored by the expression of specific markers. However, no single definitive marker of the TM has been identified. Results To identify robust markers of TM differentiation, we performed global transcriptome profiling using high-density oligonucleotide microarray on ex vivo TM tissue and cultured TM progenitors. Corneal and scleral tissues were also used in the analysis. After removal of genes expressed in the cornea and sclera, 18 genes were identified that were differentially expressed in the TM relative to the other samples. CDH23, F5, KCNAB1, FGF9, SPP1, and HEY1 were selected among the genes highly expressed in the TM, together with BDNF which was repressed, compared to progenitors for further investigation. Expression analysis by qPCR verified the differential expression and immunofluorescence of the anterior segment confirmed strong expression in the TM. Conclusions Three independent cohort of expression studies have identified novel markers, fitting in identifying TM cells and in evaluating directed TM differentiation in vitro. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3758-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Padmapriya Sathiyanathan
- Genome Institute of Singapore, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Cheryl Y Tay
- Genome Institute of Singapore, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Lawrence W Stanton
- Genome Institute of Singapore, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore. .,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore. .,Department of Biological Sciences, National University of Singapore, Singapore, Singapore.
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Mutated olfactomedin 1 in the interphotoreceptor matrix of the mouse retina causes functional deficits and vulnerability to light damage. Histochem Cell Biol 2016; 147:453-469. [PMID: 27787612 DOI: 10.1007/s00418-016-1510-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2016] [Indexed: 12/24/2022]
Abstract
Olfactomedin 1 (OLFM1) is a secreted glycoprotein and member of the olfactomedin protein family, which is preferentially expressed in various areas throughout the central nervous system. To learn about the functional properties of OLFM1 in the eye, we investigated its localization in the mouse and pig eye. In addition, we analyzed the ocular phenotype of Olfm1 mutant mice in which 52 amino acids were deleted in the central part (M2 region) of OLFM1. OLFM1 was detected in cornea, sclera, retina, and optic nerve of both wild-type and Olfm1 mutant littermates. By immunohistochemistry and double labeling with the lectin peanut agglutinin, OLFM1 was found in the interphotoreceptor matrix (IPM) of mouse and pig retina where it was directly localized to the inner segments of photoreceptors. Western blotting confirmed the presence of the OLFM1 isoforms pancortin 1 (BMY) and pancortin 2 (BMZ) in the IPM. The retinal phenotype of Olfm1 mutant mice did not obviously differ from that of wild-type littermates. In addition, outer nuclear layer (ONL) and total retinal thickness were not different, and the same was true for the area of the optic nerve in cross sections. Functional changes were observed though by electroretinography, which showed significantly lower a- and b-wave amplitudes in Olfm1 mutant mice when compared to age-matched wild-type mice. When light damage experiments were performed as an experimental paradigm of photoreceptor apoptosis, significantly more TUNEL-positive cells were observed in Olfm1 mutant mice 30 h after light exposure. One week after light exposure, the ONL was significantly thinner in Olfm1 mutant mice than in wild-type littermates indicating increased photoreceptor loss. No differences were observed when rhodopsin turnover or ERK1/2 signaling was investigated. We conclude that OLFM1 is a newly identified IPM molecule that serves an important role for photoreceptor homeostasis, which is significantly compromised in the eyes of Olfm1 mutant mice.
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Yu-Wai-Man C, Khaw PT. Personalized Medicine in Ocular Fibrosis: Myth or Future Biomarkers. Adv Wound Care (New Rochelle) 2016; 5:390-402. [PMID: 27679750 PMCID: PMC5028906 DOI: 10.1089/wound.2015.0677] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 02/04/2016] [Indexed: 02/06/2023] Open
Abstract
Significance: Fibrosis-related events play a part in the pathogenesis or failure of treatment of virtually all the blinding diseases around the world, and also account for over 40% of all deaths. It is well established that the eye and other tissues of some group of patients, for example Afro-Caribbean people, scar worse than others. However, there is a current lack of reliable biomarkers to stratify the risk of scarring and postsurgical fibrosis in the eye. Recent Advances: Recent studies using genomics, proteomics, metabolomics, clinical phenotyping, and high-resolution in vivo imaging techniques have revealed potential novel biomarkers to identify and stratify patients at risk of scarring in different fibrotic eye diseases. Critical Issues: Most of the studies, to date, have been done in animals or small cohorts of patients and future research is needed to validate these results in large longitudinal human studies. Detailed clinical phenotyping and effective biobanking of patient tissues will also be critical for future biomarker research in ocular fibrosis. Future Directions: The ability to predict the risk of scarring and to tailor the antifibrotic treatment regimen to each individual patient will be an extremely useful tool clinically to prevent undertreating, or exposing patients to unnecessary treatments with potential side effects. An exciting future prospect will be to use new advances in genotyping, namely next-generation whole genome sequencing like RNA-Seq, to develop a customized gene chip in ocular fibrosis. Successful translation of future biomarkers to benefit patient care will also ultimately require a strong collaboration between academics, pharmaceutical, and biotech companies.
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Affiliation(s)
- Cynthia Yu-Wai-Man
- National Institute for Health Research (NIHR) Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom
| | - Peng Tee Khaw
- National Institute for Health Research (NIHR) Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom
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Saccà SC, Gandolfi S, Bagnis A, Manni G, Damonte G, Traverso CE, Izzotti A. From DNA damage to functional changes of the trabecular meshwork in aging and glaucoma. Ageing Res Rev 2016; 29:26-41. [PMID: 27242026 DOI: 10.1016/j.arr.2016.05.012] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 05/25/2016] [Accepted: 05/26/2016] [Indexed: 12/24/2022]
Abstract
Glaucoma is a degenerative disease of the eye. Both the anterior and posterior segments of the eye are affected, extensive damage being detectable in the trabecular meshwork and the inner retina-central visual pathway complex. Oxidative stress is claimed to be mainly responsible for molecular damage in the anterior chamber. Indeed, oxidation harms the trabecular meshwork, leading eventually to endothelial cell decay, tissue malfunction, subclinical inflammation, changes in the extracellular matrix and cytoskeleton, altered motility, reduced outflow facility and (ultimately) increased IOP. Moreover, free radicals are involved in aging and can be produced in the brain (as well as in the eye) as a result of ischemia, leading to oxidation of the surrounding neurons. Glaucoma-related cell death occurs by means of apoptosis, and apoptosis is triggered by oxidative stress via (a) mitochondrial damage, (b) inflammation, (c) endothelial dysregulation and dysfunction, and (d) hypoxia. The proteomics of the aqueous humor is significantly altered in glaucoma as a result of oxidation-induced trabecular damage. Those proteins whose aqueous humor levels are increased in glaucoma are biomarkers of trabecular meshwork impairment. Their diffusion from the anterior to the posterior segment of the eye may be relevant in the cascade of events triggering apoptosis in the inner retinal layers, including the ganglion cells.
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Affiliation(s)
- Sergio Claudio Saccà
- IRCCS San Martino University Hospital, Department of Neuroscience and Sense Organs, San Martino Hospital, Ophthalmology Unit, Viale Benedetto XV, 16132 Genoa, Italy.
| | - Stefano Gandolfi
- Ophthalmology Unit, Department of Biological, Biotechnological and Translational Sciences, University of Parma, Parma, Italy
| | - Alessandro Bagnis
- University of Genoa, Eye Clinic, Department of Neuroscience and Sense Organs, Viale Benedetto XV, 5, 16148 Genoa, Italy
| | - Gianluca Manni
- Dept. of Clinical Science and Translational Medicine, University Tor Vergata, Rome, Italy
| | - Gianluca Damonte
- Dept. of Experimental Medicine, Section of Biochemistry and Center of Excellence for Biomedical Research, University of Genoa, Viale Benedetto XV 1, 16132 Genoa, Italy
| | - Carlo Enrico Traverso
- University of Genoa, Eye Clinic, Department of Neuroscience and Sense Organs, Viale Benedetto XV, 5, 16148 Genoa, Italy
| | - Alberto Izzotti
- Mutagenesis Unit, IRCCS San Martino University Hospital, IST National Institute for Cancer Research, Department of Health Sciences, University of Genoa, Via A. Pastore 1, Genoa I-16132, Italy
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Gheorghe SR, Crăciun AM. Matrix Gla protein in tumoral pathology. ACTA ACUST UNITED AC 2016; 89:319-21. [PMID: 27547048 PMCID: PMC4990424 DOI: 10.15386/cjmed-579] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 10/25/2015] [Indexed: 11/23/2022]
Abstract
Matrix Gla protein is a vitamin K-dependent protein secreted by chondrocytes and vascular smooth muscle cells. The presence of matrix Gla protein was reported in arterial and venous walls, lungs, kidney, uterus, heart, tooth cementum and eyes. Several studies identified matrix Gla protein in tumoral pathology. Until recently, it was thought to only have an inhibitory role of physiological and ectopic calcification. New studies demonstrated that it also has a role in physiological and pathological angiogenesis, as well as in tumorigenesis. The aim of this review is to report the latest findings related to the expression and clinical implications of matrix Gla protein in different types of cancer with an emphasis on cerebral tumors.
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Affiliation(s)
- Simona Roxana Gheorghe
- Department of Medical Biochemistry, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Alexandra Mărioara Crăciun
- Department of Medical Biochemistry, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
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Wallace DM, O'Brien CJ. The role of lamina cribrosa cells in optic nerve head fibrosis in glaucoma. Exp Eye Res 2016; 142:102-9. [PMID: 26675406 DOI: 10.1016/j.exer.2014.12.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 11/26/2014] [Accepted: 12/04/2014] [Indexed: 02/07/2023]
Abstract
Glaucoma is a chronic progressive optic neuropathy. There are extracellular matrix (ECM) changes associated with optic disc cupping in the optic nerve head (ONH) and subsequent visual field defects. The primary risk factor for onset and progression of glaucoma is raised intraocular pressure (IOP). Elevated IOP causes deformation at the ONH specifically at the lamina cribrosa (LC) region where there is also deposition of ECM causing the LC to initially undergo thickening and posterior migration with eventual shearing and collapse of the LC plates leading to a thin fibrotic connective tissue structure/scar. Cells that populate the LC region of the ONH are those cells that are positive for GFAP (the astrocytes) and those negative for GFAP (the LC cells). The LC cell plays an integral role in ECM remodelling producing ECM when exposed to high level mechanical stretch, TGF- β1 and a hypoxic environment.
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Affiliation(s)
- Deborah M Wallace
- UCD School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland; Dept. of Ophthalmology, Mater Misericordiae University Hospital, Dublin, Ireland.
| | - Colm J O'Brien
- UCD School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland; Dept. of Ophthalmology, Mater Misericordiae University Hospital, Dublin, Ireland
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Hennig R, Kuespert S, Haunberger A, Goepferich A, Fuchshofer R. Cyclic RGD peptides target human trabecular meshwork cells while ameliorating connective tissue growth factor-induced fibrosis. J Drug Target 2016; 24:952-959. [PMID: 26973018 DOI: 10.3109/1061186x.2016.1163709] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The major risk factor for primary open-angle glaucoma is increased intraocular pressure stemming from elevated outflow resistance in the trabecular meshwork (TM) region. Integrins play a pivotal role in the TM by influencing its biological properties and growth factor signaling. Pathologic changes in the TM are partially mediated by growth factors like connective tissue growth factor (CTGF). Specific targeting of TM cells could play a critical clinical role by increasing the therapeutic efficacy of nanoparticles, e.g. for nonviral gene delivery. Quantum dots with cyclo(RGDfC) covalently immobilized to their surface effectively targeted cultured TM cells and were rapidly and efficiently endocytosed by binding to αvβ3 and αvβ5 integrins. Compared to the integrin-overexpressing U87-MG cell line, the association of RGD-modified nanoparticles with the TM cells was significantly higher. Binding and uptake into TM cells was receptor-mediated and suppressible with free peptide. Soluble cyclic RGD peptides effectively attenuated CTGF-mediated effects and inhibited CTGF signaling. Due to their antagonism for αvβ3 and αvβ5 integrins, these cyclic RGD pentapeptides effectively ameliorated the CTGF-induced effects and strongly promoted specific nanoparticle association. Thus, cyclic RGD peptides are powerful multifunctional ligands for both addressing nanomaterials to the TM and interfering with pathologic CTGF signaling upon arrival.
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Affiliation(s)
- Robert Hennig
- a Department of Pharmaceutical Technology , University of Regensburg , Regensburg , Germany
| | - Sabrina Kuespert
- b Department for Human Anatomy and Embryology , University of Regensburg , Regensburg , Germany
| | - Alexandra Haunberger
- a Department of Pharmaceutical Technology , University of Regensburg , Regensburg , Germany
| | - Achim Goepferich
- a Department of Pharmaceutical Technology , University of Regensburg , Regensburg , Germany
| | - Rudolf Fuchshofer
- b Department for Human Anatomy and Embryology , University of Regensburg , Regensburg , Germany
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Abu-Hassan DW, Li X, Ryan EI, Acott TS, Kelley MJ. Induced pluripotent stem cells restore function in a human cell loss model of open-angle glaucoma. Stem Cells 2015; 33:751-61. [PMID: 25377070 PMCID: PMC4359625 DOI: 10.1002/stem.1885] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 09/18/2014] [Accepted: 10/11/2014] [Indexed: 11/06/2022]
Abstract
Normally, trabecular meshwork (TM) and Schlemm's canal inner wall endothelial cells within the aqueous humor outflow pathway maintain intraocular pressure within a narrow safe range. Elevation in intraocular pressure, because of the loss of homeostatic regulation by these outflow pathway cells, is the primary risk factor for vision loss due to glaucomatous optic neuropathy. A notable feature associated with glaucoma is outflow pathway cell loss. Using controlled cell loss in ex vivo perfused human outflow pathway organ culture, we developed compelling experimental evidence that this level of cell loss compromises intraocular pressure homeostatic function. This function was restored by repopulation of the model with fresh TM cells. We then differentiated induced pluripotent stem cells (iPSCs) and used them to repopulate this cell depletion model. These differentiated cells (TM-like iPSCs) became similar to TM cells in both morphology and expression patterns. When transplanted, they were able to fully restore intraocular pressure homeostatic function. This successful transplantation of TM-like iPSCs establishes the conceptual feasibility of using autologous stem cells to restore intraocular pressure regulatory function in open-angle glaucoma patients, providing a novel alternative treatment option. Stem Cells2015;33:751–761
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Affiliation(s)
- Diala W Abu-Hassan
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA; Department of Biochemistry & Molecular Biology, Oregon Health & Science University, Portland, Oregon, USA; Department of Biochemistry & Physiology, University of Jordan, Amman, Jordan
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Scavelli K, Chatterjee A, Rhee DJ. Secreted Protein Acidic and Rich in Cysteine in Ocular Tissue. J Ocul Pharmacol Ther 2015; 31:396-405. [PMID: 26167673 DOI: 10.1089/jop.2015.0057] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Secreted protein acidic and rich in cysteine (SPARC), also known as osteonectin or BM-40, is the prototypical matricellular protein. Matricellular proteins are nonstructural secreted proteins that provide an integration between cells and their surrounding extracellular matrix (ECM). Regulation of the ECM is important in maintaining the physiologic function of tissues. Elevated levels of SPARC have been identified in a variety of diseases involving pathologic tissue remodeling, such as hepatic fibrosis, systemic sclerosis, and certain carcinomas. Within the eye, SPARC has been identified in the trabecular meshwork, lens, and retina. Studies have begun to show the role of SPARC in these tissues and its possible role, specifically in primary open-angle glaucoma, cataracts, and proliferative vitreoretinopathy. SPARC may, therefore, be a therapeutic target in the treatment of certain ocular diseases. Further investigation into the mechanism of action of SPARC will be necessary in the development of SPARC-targeted therapy.
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Affiliation(s)
- Kurt Scavelli
- Department of Ophthalmology and Visual Sciences, University Hospitals Eye Institute, Case Western Reserve University School of Medicine , Cleveland, Ohio
| | - Ayan Chatterjee
- Department of Ophthalmology and Visual Sciences, University Hospitals Eye Institute, Case Western Reserve University School of Medicine , Cleveland, Ohio
| | - Douglas J Rhee
- Department of Ophthalmology and Visual Sciences, University Hospitals Eye Institute, Case Western Reserve University School of Medicine , Cleveland, Ohio
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Elevation of intraocular pressure in rodents using viral vectors targeting the trabecular meshwork. Exp Eye Res 2015; 141:33-41. [PMID: 26025608 DOI: 10.1016/j.exer.2015.04.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 03/20/2015] [Accepted: 04/05/2015] [Indexed: 01/30/2023]
Abstract
Rodents are increasingly being used as glaucoma models to study ocular hypertension, optic neuropathy, and retinopathy. A number of different techniques are used to elevate intraocular pressure in rodent eyes by artificially obstructing the aqueous outflow pathway. Another successful technique to induce ocular hypertension is to transduce the trabecular meshwork of rodent eyes with viral vectors expressing glaucoma associated transgenes to provide more relevant models of glaucomatous damage to the trabecular meshwork. This technique has been used to validate newly discovered glaucoma pathogenesis pathways as well as to develop rodent models of primary open angle glaucoma. Ocular hypertension has successfully been induced by adenovirus 5 mediated delivery of mutant MYOC, bioactivated TGFβ2, SFRP1, DKK1, GREM1, and CD44. Advantages of this approach are: selective tropism for the trabecular meshwork, the ability to use numerous mouse strains, and the relatively rapid onset of IOP elevation. Disadvantages include mild-to-moderate ocular inflammation induced by the Ad5 vector and sometimes transient transgene expression. Current efforts are focused at discovering less immunogenic viral vectors that have tropism for the trabecular meshwork and drive sufficient transgene expression to induce ocular hypertension. This viral vector approach allows rapid proof of concept studies to study glaucomatous damage to the trabecular meshwork without the expensive and time-consuming generation of transgenic mouse lines.
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Zhao Y, Sorenson CM, Sheibani N. Cytochrome P450 1B1 and Primary Congenital Glaucoma. J Ophthalmic Vis Res 2015; 10:60-7. [PMID: 26005555 PMCID: PMC4424721 DOI: 10.4103/2008-322x.156116] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 04/19/2014] [Indexed: 01/08/2023] Open
Abstract
Cytochrome P450 1B1 (Cyp1b1) belongs to the CYP450 superfamily of heme-binding mono-oxygenases which catalyze oxidation of various endogenous and exogenous substrates. The expression of Cyp1b1 plays an important role in the modulation of development and functions of the trabecular meshwork (TM). Mutations in Cyp1b1 have been reported in patients with primary congenital glaucoma (PCG). Mice lacking Cyp1b1 also exhibit developmental defects in the TM similar to those reported in congenital glaucoma patients. However, how Cyp1b1 deficiency contributes to TM dysgenesis remains unknown. In the present review, we will address the significance of Cyp1b1 expression and/or its function in anterior segment development. Cyp1b1-deficient (Cyp1b1−/−) mice are discussed as a promising model for an oxidative stress-induced model of PCG, in which Cyp1b1 activity is revealed as an important modulator of oxidative homeostasis contributing to the development and structural function of the TM. This conclusion suggests a possible clinical intervention for individuals who are genetically at high risk of developing PCG.
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Affiliation(s)
- Yun Zhao
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Christine M Sorenson
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA ; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Nader Sheibani
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA ; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
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Wallace DM, Pokrovskaya O, O'Brien CJ. The Function of Matricellular Proteins in the Lamina Cribrosa and Trabecular Meshwork in Glaucoma. J Ocul Pharmacol Ther 2015; 31:386-95. [PMID: 25848892 DOI: 10.1089/jop.2014.0163] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE To review the current literature regarding the role of matricellular proteins in glaucoma, specifically in the lamina cribrosa (LC) region of the optic nerve head (ONH) and the trabecular meshwork (TM). METHODS A literature search was performed for published articles describing the expression and function of matricellular proteins such as thrombospondin (TSP), connective tissue growth factor (CTGF), secreted protein acidic and rich in cysteine (SPARC), and periostin in glaucoma. RESULTS In glaucoma, there are characteristic extracellular matrix (ECM) changes associated with optic disc cupping in the ONH and subsequent visual field defects. Matricellular proteins are a family of nonstructural secreted glycoproteins, which enable cells to communicate with their surrounding ECM, including CTGF, also known as CCN2, TSPs, SPARC, periostin, osteonectin, and tenascin-C and -X, and other ECM proteins. Such proteins appear to play a role in fibrosis and increased ECM deposition. Importantly, most are widely expressed in tissues particularly in the TM and ONH, and deficiency of TSP1 and SPARC has been shown to lower intraocular pressure in mouse models of glaucoma through enhanced outflow facility. CONCLUSION This article highlights the role of matricellular proteins in glaucoma pathology. The potential role of these proteins in glaucoma is emerging as some have an association with the pathophysiology of the TM and LC region and might therefore be potential targets for therapeutic intervention in glaucoma.
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Affiliation(s)
- Deborah M Wallace
- 1 School of Medicine and Medical Science, University College Dublin , Dublin, Ireland .,2 Department of Ophthalmology, Mater Misericordiae University Hospital , Dublin, Ireland
| | - Olya Pokrovskaya
- 1 School of Medicine and Medical Science, University College Dublin , Dublin, Ireland .,2 Department of Ophthalmology, Mater Misericordiae University Hospital , Dublin, Ireland
| | - Colm J O'Brien
- 1 School of Medicine and Medical Science, University College Dublin , Dublin, Ireland .,2 Department of Ophthalmology, Mater Misericordiae University Hospital , Dublin, Ireland
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Borrás T, Smith MH, Buie LK. A Novel Mgp-Cre Knock-In Mouse Reveals an Anticalcification/Antistiffness Candidate Gene in the Trabecular Meshwork and Peripapillary Scleral Region. Invest Ophthalmol Vis Sci 2015; 56:2203-14. [PMID: 25711639 PMCID: PMC4406033 DOI: 10.1167/iovs.15-16460] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 02/14/2015] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Soft tissue calcification is a pathological condition. Matrix Gla (MGP) is a potent mineralization inhibitor secreted by cartilage chondrocytes and arteries' vascular smooth muscle cells. Mgp knock-out mice die at 6 weeks due to massive arterial calcification. Arterial calcification results in arterial stiffness and higher systolic blood pressure. Intriguingly, MGP was highly abundant in trabecular meshwork (TM). Because tissue stiffness is relevant to glaucoma, we investigated which additional eye tissues use Mgp's function using knock-in mice. METHODS An Mgp-Cre-recombinase coding sequence (Cre) knock-in mouse, containing Mgp DNA plus an internal ribosomal entry site (IRES)-Cre-cassette was generated by homologous recombination. Founders were crossed with Cre-mediated reporter mouse R26R-lacZ. Their offspring expresses lacZ where Mgp is transcribed. Eyes from MgpCre/+;R26RlacZ/+ (Mgp-lacZ knock-in) and controls, 1 to 8 months were assayed for β-gal enzyme histochemistry. RESULTS As expected, Mgp-lacZ knock-in's TM was intensely blue. In addition, this mouse revealed high specific expression in the sclera, particularly in the peripapillary scleral region (ppSC). Ciliary muscle and sclera above the TM were also positive. Scleral staining was located immediately underneath the choroid (chondrocyte layer), began midsclera and was remarkably high in the ppSC. Cornea, iris, lens, ciliary body, and retina were negative. All mice exhibited similar staining patterns. All controls were negative. CONCLUSIONS Matrix Gla's restricted expression to glaucoma-associated tissues from anterior and posterior segments suggests its involvement in the development of the disease. Matrix Gla's anticalcification/antistiffness properties in the vascular tissue, together with its high TM and ppCS expression, place this gene as a strong candidate for TM's softness and sclera's stiffness regulation in glaucoma.
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Affiliation(s)
- Teresa Borrás
- Department of Ophthalmology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States
| | - Matthew H. Smith
- Department of Ophthalmology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States
| | - LaKisha K. Buie
- Department of Ophthalmology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States
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Joe MK, Nakaya N, Abu-Asab M, Tomarev SI. Mutated myocilin and heterozygous Sod2 deficiency act synergistically in a mouse model of open-angle glaucoma. Hum Mol Genet 2015; 24:3322-34. [PMID: 25740847 DOI: 10.1093/hmg/ddv082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 03/02/2015] [Indexed: 11/14/2022] Open
Abstract
Glaucoma is a multifactorial optic neuropathy characterized by retinal ganglion cell (RGC) death and axonal degeneration leading to irreversible blindness. Mutations in the myocilin (MYOC) gene are the most common genetic factors of primary open-angle glaucoma. To develop a genetic mouse model induced by the synergistic interaction of mutated myocilin and another significant risk factor, oxidative stress, we produced double-mutant mice (Tg-MYOC(Y437H/+)/Sod2(+/-)) bearing human MYOC with a Y437H point mutation and a heterozygous deletion of the gene for the primary antioxidant enzyme, superoxide dismutase 2 (SOD2). Sod2 is broadly expressed in most tissues including the trabecular meshwork (TM) and heterozygous Sod2 knockout mice exhibit the reduced SOD2 activity and oxidative stress in all studied tissues. Accumulation of Y437H myocilin in the TM induced endoplasmic reticulum stress and led to a 45% loss of smooth muscle alpha-actin positive cells in the eye drainage structure of 10- to 12-month-old Tg-MYOC(Y437H/+)/Sod2(+/-) mice as compared with wild-type littermates. Tg-MYOC(Y437H/+)/Sod2(+/-) mice had higher intraocular pressure, lost about 37% of RGCs in the peripheral retina, and exhibited axonal degeneration in the retina and optic nerve as compared with their wild-type littermates. Single-mutant littermates containing MYOC(Y437H/+) or Sod2(+/-) exhibited no significant pathological changes until 12 months of age. Additionally, we observed elevated expression of endothelial leukocyte adhesion molecule-1, a human glaucoma marker, in the TM of Tg-MYOC(Y437H/+)/Sod2(+/-) mice. This is the first reported animal glaucoma model that combines expression of a glaucoma-causing mutant gene and an additional mutation mimicking a deleterious environment factor that acts synergistically.
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Affiliation(s)
- Myung Kuk Joe
- Section on Retinal Ganglion Cell Biology, Laboratory of Retinal Cell and Molecular Biology and
| | - Naoki Nakaya
- Section on Retinal Ganglion Cell Biology, Laboratory of Retinal Cell and Molecular Biology and
| | - Mones Abu-Asab
- Histology Core, National Eye Institute, NIH, Bethesda, MD 20895, USA
| | - Stanislav I Tomarev
- Section on Retinal Ganglion Cell Biology, Laboratory of Retinal Cell and Molecular Biology and
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Morgan JT, Kwon HS, Wood JA, Borjesson DL, Tomarev SI, Murphy CJ, Russell P. Thermally labile components of aqueous humor potently induce osteogenic potential in adipose-derived mesenchymal stem cells. Exp Eye Res 2015; 135:127-33. [PMID: 25720657 DOI: 10.1016/j.exer.2015.02.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Revised: 02/12/2015] [Accepted: 02/22/2015] [Indexed: 12/13/2022]
Abstract
Adipose-derived mesenchymal stem cells (ASCs) hold promise for use in cell-based therapies. Their intrinsic anti-inflammatory properties are potentially useful for treatments of inflammatory conditions such as uveitis, while their ability to differentiate along multiple cell lineages suggests use in regenerating damaged or degenerated tissue. However, how ASCs will respond to the intraocular environment is poorly studied. We have recently reported that aqueous humor (AH), the fluid that nourishes the anterior segment of the eye, potently increases alkaline phosphatase (ALP) activity of ASCs, indicating osteogenic differentiation. Here, we expand on our previous findings to better define the nature of this response. To this end, we cultured ASCs in the presence of 0, 5, 10, and 20% AH and assayed them for ALP activity. We found ALP activity correlates with increasing AH concentrations from 5 to 20%, and that longer treatments result in increased ALP activity. By using serum free media and pretreating AH with dextran-coated charcoal, we found that serum and charcoal-adsorbable AH components augment but are not required for this response. Further, by heat-treating the AH, we established that thermally labile components are required for the osteogenic response. Finally, we showed myocilin, a protein present in AH, could induce ALP activity in ASCs. However, this was to a lesser extent than untreated 5% AH, and myocilin could only partially rescue the effect after heat treatment, documenting there were additional thermally labile constituents of AH involved in the osteogenic response. Our work adds to the understanding of the induction of ALP in ASCs following exposure to AH, providing important insight in how ASCs will be influenced by the ocular environment. In conclusion, increased osteogenic potential upon exposure to AH represents a potential challenge to developing ASC cell-based therapies directed at the eye.
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Affiliation(s)
- Joshua T Morgan
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, USA
| | - Heung Sun Kwon
- Section of Retinal Ganglion Cell Biology, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, NIH, Bethesda, MD, USA
| | - Joshua A Wood
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Dori L Borjesson
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Stanislav I Tomarev
- Section of Retinal Ganglion Cell Biology, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, NIH, Bethesda, MD, USA
| | - Christopher J Murphy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, USA; Department of Ophthalmology & Vision Science, School of Medicine, University of California, Davis, USA
| | - Paul Russell
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, USA.
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Kuespert S, Junglas B, Braunger BM, Tamm ER, Fuchshofer R. The regulation of connective tissue growth factor expression influences the viability of human trabecular meshwork cells. J Cell Mol Med 2015; 19:1010-20. [PMID: 25704370 PMCID: PMC4420603 DOI: 10.1111/jcmm.12492] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 10/13/2014] [Indexed: 11/30/2022] Open
Abstract
Connective tissue growth factor (CTGF) induces extracellular matrix (ECM) synthesis and contractility in human trabecular meshwork (HTM) cells. Both processes are involved in the pathogenesis of primary open-angle glaucoma. To date, little is known about regulation and function of CTGF expression in the trabecular meshwork (TM). Therefore, we analysed the effects of different aqueous humour proteins and stressors on CTGF expression in HTM cells. HTM cells from three different donors were treated with endothelin-1, insulin-like growth factor (IGF)-1, angiotensin-II, H2O2 and heat shock and were analysed by immunohistochemistry, real-time RT-PCR and Western blotting. Viability after H2O2 treatment was measured in CTGF silenced HTM-N cells and their controls. Latrunculin A reduced expression of CTGF by about 50% compared to untreated HTM cells, whereas endothelin-1, IGF-1, angiotensin-II, heat shock and oxidative stress led to a significant increase. Silencing of CTGF resulted in a delayed expression of αB-crystallin and in reduced cell viability in comparison to the controls after oxidative stress. Conversely, CTGF treatment led to a higher cell viability rate after H2O2 treatment. CTGF expression is induced by factors that have been linked to glaucoma. An increased level of CTGF appears to protect TM cells against damage induced by stress. The beneficial effect of CTGF for viability of TM cells is likely associated with the effects on increased ECM synthesis and higher contractility of the TM, thereby contributing to reduced aqueous humour outflow facility causing increased intraocular pressure.
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Affiliation(s)
- Sabrina Kuespert
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
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