1
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Lee SJ, Emery D, Vukmanic E, Wang Y, Lu X, Wang W, Fortuny E, James R, Kaplan HJ, Liu Y, Du J, Dean DC. Metabolic transcriptomics dictate responses of cone photoreceptors to retinitis pigmentosa. Cell Rep 2023; 42:113054. [PMID: 37656622 PMCID: PMC10591869 DOI: 10.1016/j.celrep.2023.113054] [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: 05/08/2023] [Revised: 06/21/2023] [Accepted: 08/15/2023] [Indexed: 09/03/2023] Open
Abstract
Most mutations in retinitis pigmentosa (RP) arise in rod photoreceptors, but cone photoreceptors, responsible for high-resolution daylight and color vision, are subsequently affected, causing the most debilitating features of the disease. We used mass spectroscopy to follow 13C metabolites delivered to the outer retina and single-cell RNA sequencing to assess photoreceptor transcriptomes. The S cone metabolic transcriptome suggests engagement of the TCA cycle and ongoing response to ROS characteristic of oxidative phosphorylation, which we link to their histone modification transcriptome. Tumor necrosis factor (TNF) and its downstream effector RIP3, which drive ROS generation via mitochondrial dysfunction, are induced and activated as S cones undergo early apoptosis in RP. The long/medium-wavelength (L/M) cone transcriptome shows enhanced glycolytic capacity, which maintains their function as RP progresses. Then, as extracellular glucose eventually diminishes, L/M cones are sustained in long-term dormancy by lactate metabolism.
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Affiliation(s)
- Sang Joon Lee
- Department of Medicine, Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY 40202, USA; Department of Ophthalmology, Kosin University College of Medicine, #262 Gamcheon-ro, Seo-gu, Busan 49267, Korea
| | - Douglas Emery
- Department of Medicine, Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Eric Vukmanic
- Department of Medicine, Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Yekai Wang
- Departments of Ophthalmology and Visual Sciences and Biochemistry and Molecular Medicine, West Virginia University, Morgantown, WV 26506, USA
| | - Xiaoqin Lu
- Department of Medicine, Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Wei Wang
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Enzo Fortuny
- Department of Neurosurgery, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Robert James
- Department of Neurosurgery, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Henry J Kaplan
- Department of Ophthalmology, St. Louis University School of Medicine, St. Louis MO 63110, USA
| | - Yongqing Liu
- Department of Medicine, Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Jianhai Du
- Departments of Ophthalmology and Visual Sciences and Biochemistry and Molecular Medicine, West Virginia University, Morgantown, WV 26506, USA.
| | - Douglas C Dean
- Department of Medicine, Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY 40202, USA.
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2
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Vagni P, Airaghi Leccardi MJI, Vila CH, Zollinger EG, Sherafatipour G, Wolfensberger TJ, Ghezzi D. POLYRETINA restores light responses in vivo in blind Göttingen minipigs. Nat Commun 2022; 13:3678. [PMID: 35760775 PMCID: PMC9237028 DOI: 10.1038/s41467-022-31180-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 06/03/2022] [Indexed: 11/09/2022] Open
Abstract
Retinal prostheses hold the potential for artificial vision in blind people affected by incurable diseases of the outer retinal layer. Available technologies provide only a small field of view: a significant limitation for totally blind people. To overcome this problem, we recently proposed a large and high-density photovoltaic epiretinal device, known as POLYRETINA. Here, we report the in vivo assessment of POLYRETINA. First, we characterise a model of chemically-induced blindness in Göttingen minipigs. Then, we develop and test a minimally invasive injection procedure to insert the large epiretinal implant into the eye. Last, we show that POLYRETINA restores light-evoked cortical responses in blind animals at safe irradiance levels. These results indicate that POLYRETINA holds the potential for artificial vision in totally blind patients affected by retinitis pigmentosa.
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Affiliation(s)
- Paola Vagni
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Marta Jole Ildelfonsa Airaghi Leccardi
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Charles-Henri Vila
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Elodie Geneviève Zollinger
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Golnaz Sherafatipour
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Thomas J Wolfensberger
- Department of Ophthalmology, University of Lausanne, Hôpital Ophtalmique Jules-Gonin, Fondation Asile des Aveugles, Lausanne, Switzerland
| | - Diego Ghezzi
- Medtronic Chair in Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland.
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3
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Grotz S, Schäfer J, Wunderlich KA, Ellederova Z, Auch H, Bähr A, Runa-Vochozkova P, Fadl J, Arnold V, Ardan T, Veith M, Santamaria G, Dhom G, Hitzl W, Kessler B, Eckardt C, Klein J, Brymova A, Linnert J, Kurome M, Zakharchenko V, Fischer A, Blutke A, Döring A, Suchankova S, Popelar J, Rodríguez-Bocanegra E, Dlugaiczyk J, Straka H, May-Simera H, Wang W, Laugwitz KL, Vandenberghe LH, Wolf E, Nagel-Wolfrum K, Peters T, Motlik J, Fischer MD, Wolfrum U, Klymiuk N. Early disruption of photoreceptor cell architecture and loss of vision in a humanized pig model of usher syndromes. EMBO Mol Med 2022; 14:e14817. [PMID: 35254721 PMCID: PMC8988205 DOI: 10.15252/emmm.202114817] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 02/04/2022] [Accepted: 02/09/2022] [Indexed: 01/17/2023] Open
Abstract
Usher syndrome (USH) is the most common form of monogenic deaf-blindness. Loss of vision is untreatable and there are no suitable animal models for testing therapeutic strategies of the ocular constituent of USH, so far. By introducing a human mutation into the harmonin-encoding USH1C gene in pigs, we generated the first translational animal model for USH type 1 with characteristic hearing defect, vestibular dysfunction, and visual impairment. Changes in photoreceptor architecture, quantitative motion analysis, and electroretinography were characteristics of the reduced retinal virtue in USH1C pigs. Fibroblasts from USH1C pigs or USH1C patients showed significantly elongated primary cilia, confirming USH as a true and general ciliopathy. Primary cells also proved their capacity for assessing the therapeutic potential of CRISPR/Cas-mediated gene repair or gene therapy in vitro. AAV-based delivery of harmonin into the eye of USH1C pigs indicated therapeutic efficacy in vivo.
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Affiliation(s)
- Sophia Grotz
- Chair of Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Jessica Schäfer
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg University (JGU), Mainz, Germany
| | - Kirsten A Wunderlich
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg University (JGU), Mainz, Germany
| | - Zdenka Ellederova
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic
| | - Hannah Auch
- Chair of Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Andrea Bähr
- Center for Innovative Medical Models, LMU Munich, Munich, Germany.,Large Animal Models in Cardiovascular Research, Internal Medical Department I, TU Munich, Munich, Germany
| | - Petra Runa-Vochozkova
- Large Animal Models in Cardiovascular Research, Internal Medical Department I, TU Munich, Munich, Germany
| | - Janet Fadl
- Chair of Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany.,Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg University (JGU), Mainz, Germany
| | - Vanessa Arnold
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg University (JGU), Mainz, Germany
| | - Taras Ardan
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic
| | - Miroslav Veith
- Ophthalmology Clinic, University Hospital Kralovske Vinohrady, Praha, Czech Republic
| | - Gianluca Santamaria
- Large Animal Models in Cardiovascular Research, Internal Medical Department I, TU Munich, Munich, Germany
| | - Georg Dhom
- Chair of Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Wolfgang Hitzl
- Biostatistics and Data Science, Paracelsus Medical University, Salzburg, Austria
| | - Barbara Kessler
- Chair of Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Christian Eckardt
- Center for Innovative Medical Models, LMU Munich, Munich, Germany.,Large Animal Models in Cardiovascular Research, Internal Medical Department I, TU Munich, Munich, Germany
| | - Joshua Klein
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg University (JGU), Mainz, Germany
| | - Anna Brymova
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic
| | - Joshua Linnert
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg University (JGU), Mainz, Germany
| | - Mayuko Kurome
- Chair of Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Valeri Zakharchenko
- Chair of Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Andrea Fischer
- Veterinary Faculty, Small Animal Clinics, LMU Munich, Munich, Germany
| | - Andreas Blutke
- Institute of Experimental Genetics, Helmholtz Center Munich, Neuherberg, Germany
| | - Anna Döring
- Veterinary Faculty, Small Animal Clinics, LMU Munich, Munich, Germany
| | - Stepanka Suchankova
- Institute of Experimental Medicine, Czech Academy of Science, Prague, Czech Republic
| | - Jiri Popelar
- Institute of Experimental Medicine, Czech Academy of Science, Prague, Czech Republic
| | - Eduardo Rodríguez-Bocanegra
- Centre for Ophthalmology, University Eye Hospital, University Hospital Tübingen, Tübingen, Germany.,Institute for Ophthalmic Research, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany
| | - Julia Dlugaiczyk
- Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Zurich (USZ), University of Zurich, Zurich, Switzerland
| | - Hans Straka
- Faculty of Biology, LMU Munich, Planegg, Germany
| | - Helen May-Simera
- Institute of Molecular Physiology, Cilia Biology, JGU Mainz, Mainz, Germany
| | - Weiwei Wang
- Grousbeck Gene Therapy Center, Mass Eye and Ear and Harvard Medical School, Boston, MA, USA
| | - Karl-Ludwig Laugwitz
- Large Animal Models in Cardiovascular Research, Internal Medical Department I, TU Munich, Munich, Germany
| | - Luk H Vandenberghe
- Grousbeck Gene Therapy Center, Mass Eye and Ear and Harvard Medical School, Boston, MA, USA
| | - Eckhard Wolf
- Chair of Molecular Animal Breeding and Biotechnology, LMU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Kerstin Nagel-Wolfrum
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg University (JGU), Mainz, Germany.,Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University (JGU), Mainz, Germany
| | - Tobias Peters
- Centre for Ophthalmology, University Eye Hospital, University Hospital Tübingen, Tübingen, Germany.,Institute for Ophthalmic Research, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany
| | - Jan Motlik
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic
| | - M Dominik Fischer
- Oxford Eye Hospital, Oxford University NHS Foundation Trust, Oxford, UK.,Nuffield Laboratory of Ophthalmology, NDCN, University of Oxford, Oxford, UK
| | - Uwe Wolfrum
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg University (JGU), Mainz, Germany
| | - Nikolai Klymiuk
- Center for Innovative Medical Models, LMU Munich, Munich, Germany.,Large Animal Models in Cardiovascular Research, Internal Medical Department I, TU Munich, Munich, Germany
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4
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Viegas FO, Neuhauss SCF. A Metabolic Landscape for Maintaining Retina Integrity and Function. Front Mol Neurosci 2021; 14:656000. [PMID: 33935647 PMCID: PMC8081888 DOI: 10.3389/fnmol.2021.656000] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 03/22/2021] [Indexed: 01/27/2023] Open
Abstract
Neurons have high metabolic demands that are almost exclusively met by glucose supplied from the bloodstream. Glucose is utilized in complex metabolic interactions between neurons and glia cells, described by the astrocyte-neuron lactate shuttle (ANLS) hypothesis. The neural retina faces similar energy demands to the rest of the brain, with additional high anabolic needs to support continuous renewal of photoreceptor outer segments. This demand is met by a fascinating variation of the ANLS in which photoreceptors are the central part of a metabolic landscape, using glucose and supplying surrounding cells with metabolic intermediates. In this review we summarize recent evidence on how neurons, in particular photoreceptors, meet their energy and biosynthetic requirements by comprising a metabolic landscape of interdependent cells.
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Affiliation(s)
- Filipe O Viegas
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland.,Life Science Zurich Graduate School, Ph.D. Program in Molecular Life Sciences, Zurich, Switzerland
| | - Stephan C F Neuhauss
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
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5
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Pan WW, Wubben TJ, Besirli CG. Photoreceptor metabolic reprogramming: current understanding and therapeutic implications. Commun Biol 2021; 4:245. [PMID: 33627778 PMCID: PMC7904922 DOI: 10.1038/s42003-021-01765-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 01/28/2021] [Indexed: 02/06/2023] Open
Abstract
Acquired and inherited retinal disorders are responsible for vision loss in an increasing proportion of individuals worldwide. Photoreceptor (PR) death is central to the vision loss individuals experience in these various retinal diseases. Unfortunately, there is a lack of treatment options to prevent PR loss, so an urgent unmet need exists for therapies that improve PR survival and ultimately, vision. The retina is one of the most energy demanding tissues in the body, and this is driven in large part by the metabolic needs of PRs. Recent studies suggest that disruption of nutrient availability and regulation of cell metabolism may be a unifying mechanism in PR death. Understanding retinal cell metabolism and how it is altered in disease has been identified as a priority area of research. The focus of this review is on the recent advances in the understanding of PR metabolism and how it is critical to reduction-oxidation (redox) balance, the outer retinal metabolic ecosystem, and retinal disease. The importance of these metabolic processes is just beginning to be realized and unraveling the metabolic and redox pathways integral to PR health may identify novel targets for neuroprotective strategies that prevent blindness in the heterogenous group of retinal disorders.
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Affiliation(s)
- Warren W Pan
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, MI, USA
| | - Thomas J Wubben
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, MI, USA.
| | - Cagri G Besirli
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, MI, USA.
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6
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Lee SJ, Wang W, Jin L, Lu X, Gao L, Chen Y, Liu T, Emery D, Vukmanic E, Liu Y, Kaplan HJ, Dean DC. Rod photoreceptor clearance due to misfolded rhodopsin is linked to a DAMP-immune checkpoint switch. J Biol Chem 2021; 296:100102. [PMID: 33214223 PMCID: PMC7949052 DOI: 10.1074/jbc.ra120.016053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/13/2020] [Accepted: 11/19/2020] [Indexed: 01/19/2023] Open
Abstract
Chronic endoplasmic reticulum stress resulting from misfolding of the visual pigment rhodopsin (RHO) can lead to loss of rod photoreceptors, which initiates retinitis pigmentosa, characterized initially by diminished nighttime and peripheral vision. Cone photoreceptors depend on rods for glucose transport, which the neurons use for assembly of visual pigment-rich structures; as such, loss of rods also leads to a secondary loss of cone function, diminishing high-resolution color vision utilized for tasks including reading, driving, and facial recognition. If dysfunctional rods could be maintained to continue to serve this secondary cone preservation function, it might benefit patients with retinitis pigmentosa, but the mechanisms by which rods are removed are not fully established. Using pigs expressing mutant RHO, we find that induction of a danger-associated molecular pattern (DAMP) "eat me" signal on the surface of mutant rods is correlated with targeting the live cells for (PrCR) by retinal myeloid cells. Glucocorticoid therapy leads to replacement of this DAMP with a "don't eat me" immune checkpoint on the rod surface and inhibition of PrCR. Surviving rods then continue to promote glucose transport to cones, maintaining their viability.
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Affiliation(s)
- Sang Joon Lee
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA; Department of Ophthalmology, Kosin University College of Medicine, Seo-gu, Busan, Korea
| | - Wei Wang
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA
| | - Lei Jin
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA; Department of Ophthalmology, The Third People's Hospital of Dalian, Dalian Medical University, Dalian, China
| | - Xiaoqin Lu
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA; Department of Medicine, University of Louisville Health Sciences Center, Louisville, Kentucky, USA
| | - Lei Gao
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA; Department of Hematology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yao Chen
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA; Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
| | - Tingting Liu
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA; Department of Ophthalmology, The Third People's Hospital of Dalian, Dalian Medical University, Dalian, China
| | - Douglas Emery
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA; Department of Medicine, University of Louisville Health Sciences Center, Louisville, Kentucky, USA
| | - Eric Vukmanic
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA; Department of Medicine, University of Louisville Health Sciences Center, Louisville, Kentucky, USA
| | - Yongqing Liu
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA; Department of Medicine, University of Louisville Health Sciences Center, Louisville, Kentucky, USA
| | - Henry J Kaplan
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA
| | - Douglas C Dean
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky, USA; Department of Medicine, University of Louisville Health Sciences Center, Louisville, Kentucky, USA.
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7
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Metabolic Deregulation of the Blood-Outer Retinal Barrier in Retinitis Pigmentosa. Cell Rep 2020; 28:1323-1334.e4. [PMID: 31365873 PMCID: PMC6693665 DOI: 10.1016/j.celrep.2019.06.093] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 05/31/2019] [Accepted: 06/26/2019] [Indexed: 02/07/2023] Open
Abstract
Retinitis pigmentosa (RP) initiates with diminished rod photoreceptor function, causing peripheral and nighttime vision loss. However, subsequent loss of cone function and high-resolution daylight and color vision is most debilitating. Visual pigment-rich photoreceptor outer segments (OS) undergo phagocytosis by the retinal pigment epithelium (RPE), and the RPE also acts as a blood-outer retinal barrier transporting nutrients, including glucose, to photoreceptors. We provide evidence that contact between externalized phosphatidylserine (PS) on OS tips and apical RPE receptors activates Akt, linking phagocytosis with glucose transport to photoreceptors for new OS synthesis. As abundant mutant rod OS tips shorten in RP, Akt activation is lost, and onset of glucose metabolism in the RPE and diminished glucose transport combine to cause photoreceptor starvation and accompanying retinal metabolome changes. Subretinal injection of OS tip mimetics displaying PS restores Akt activation, glucose transport, and cone function in end-stage RP after rods are lost. Wang et al. show that onset of glucose metabolism in the retinal pigment epithelium (RPE), which acts as the blood-outer retinal barrier, and inhibition of RPE glucose transport to photoreceptors combine to cause photoreceptor starvation and vision loss in retinitis pigmentosa.
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8
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Noh GM, Lim JW, Lee MS, Lee SU, Lee SJ. Analysis of Changes in Retinal Photoreceptors Using Optical Coherence Tomography in a Feline Model of Iodoacetic Acid-induced Retinal Degeneration. KOREAN JOURNAL OF OPHTHALMOLOGY 2020; 33:547-556. [PMID: 31833252 PMCID: PMC6911790 DOI: 10.3341/kjo.2019.0082] [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: 07/13/2019] [Revised: 08/27/2019] [Accepted: 09/06/2019] [Indexed: 11/23/2022] Open
Abstract
Purpose We investigated structural changes in the retina by using optical coherence tomography (OCT) in a feline model of retinal degeneration using iodoacetic acid (IAA). Methods We examined 22 eyes of 11 felines over 2 years of age. The felines had fasted for 12 hours and were intravenously injected with IAA 20 mg/kg of body weight. OCT (Spectralis OCT) was performed at the point where the ends of the retinal vessels collected in the lateral direction from the optic nerve head and area centralis. Similarly, OCT was performed four times at 1-week intervals following injections, at which point the felines were sacrificed and histologic examinations were performed. Using OCT, the thickness of each layer of the retina was measured. Results The average body weight of the three male and eight female felines investigated in this study was 1.61 ± 0.19 kg. The mean total retinal thickness of the felines before injection was 221.32 ± 9.82 µm, with a significant decrease in the retinal thickness at 2, 3, and 4 weeks following injections of 186.41 ± 35.42, 174.56 ± 31.94, and 175.35 ± 33.84 µm, respectively (p = 0.028, 0.027, and 0.027, respectively). The thickness of the outer nuclear layer was 57.49 ± 8.03 µm before injection and 29.26 ± 17.87, 25.62 ± 13.88, and 31.60 ± 18.38 µm at 2, 3, and 4 weeks, respectively, after injection (p = 0.028, 0.028, 0.046, respectively). Conclusions In a feline model of retinal degeneration using IAA, the total retinal thickness and the thickness of the outer nuclear layer were shown to decrease significantly on OCT.
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Affiliation(s)
- Gwang Myeong Noh
- Department of Ophthalmology, Kosin University College of Medicine, Busan, Korea
| | - Jae Wan Lim
- Yangsan-si Dong-myeon Local Public Health Clinic, Busan, Korea
| | - Myung Shin Lee
- Department of Ophthalmology, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Seung Uk Lee
- Department of Ophthalmology, Kosin University College of Medicine, Busan, Korea
| | - Sang Joon Lee
- Department of Ophthalmology, Kosin University College of Medicine, Busan, Korea.
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9
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Gorbatyuk MS, Starr CR, Gorbatyuk OS. Endoplasmic reticulum stress: New insights into the pathogenesis and treatment of retinal degenerative diseases. Prog Retin Eye Res 2020; 79:100860. [PMID: 32272207 DOI: 10.1016/j.preteyeres.2020.100860] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 03/08/2020] [Accepted: 03/17/2020] [Indexed: 12/13/2022]
Abstract
Physiological equilibrium in the retina depends on coordinated work between rod and cone photoreceptors and can be compromised by the expression of mutant proteins leading to inherited retinal degeneration (IRD). IRD is a diverse group of retinal dystrophies with multifaceted molecular mechanisms that are not fully understood. In this review, we focus on the contribution of chronically activated unfolded protein response (UPR) to inherited retinal pathogenesis, placing special emphasis on studies employing genetically modified animal models. As constitutively active UPR in degenerating retinas may activate pro-apoptotic programs associated with oxidative stress, pro-inflammatory signaling, dysfunctional autophagy, free cytosolic Ca2+ overload, and altered protein synthesis rate in the retina, we focus on the regulatory mechanisms of translational attenuation and approaches to overcoming translational attenuation in degenerating retinas. We also discuss current research on the role of the UPR mediator PERK and its downstream targets in degenerating retinas and highlight the therapeutic benefits of reprogramming PERK signaling in preclinical animal models of IRD. Finally, we describe pharmacological approaches targeting UPR in ocular diseases and consider their potential applications to IRD.
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Affiliation(s)
- Marina S Gorbatyuk
- The University of Alabama at Birmingham, Department of Optometry and Vision Science, School of Optometry, USA.
| | - Christopher R Starr
- The University of Alabama at Birmingham, Department of Optometry and Vision Science, School of Optometry, USA
| | - Oleg S Gorbatyuk
- The University of Alabama at Birmingham, Department of Optometry and Vision Science, School of Optometry, USA
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10
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Barone F, Muscatello LV, Ventrella D, Elmi A, Romagnoli N, Mandrioli L, Maya-Vetencourt JF, Bombardi C, Mete M, Sarli G, Benfenati F, Pertile G, Bacci ML. The porcine iodoacetic acid model of retinal degeneration: Morpho-functional characterization of the visual system. Exp Eye Res 2020; 193:107979. [PMID: 32087230 DOI: 10.1016/j.exer.2020.107979] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 02/13/2020] [Accepted: 02/16/2020] [Indexed: 10/25/2022]
Abstract
Porcine models of ophthalmological diseases are often used in pre-clinical translational studies due to pigs' similarities to humans. In particular, the iodoacetic acid (IAA) model of photoreceptor degeneration seems to mimic well the endstage phenotype of human pathologies as retinitis pigmentosa and age-related macular degeneration, with high potential for prosthesis/retinal devices testing. IAA is capable of inducing photoreceptor death by blockage of glycolysis, and its effects on the retina have been described. Nonetheless, up to date, literature lacks of a comprehensive morpho-functional characterization of the entire visual system of this model. This gap is particularly critical for prosthesis testing as inner retinal structures and optic pathways must be preserved to elicit cortical responses and restore vision. In this study, we investigated the functional and anatomical features of the visual system of IAA-treated pigs and compared them to control animals. IAA was administered intravenously at 12 mg/kg; control animals received saline solution (NaCl 0.9% w/v). Electrophysiological analyses included full-field (ffERGs) and pattern (PERGs) electroretinograms and flash visually evoked potentials (fVEPs). Histological evaluations were performed on the retina and the optic pathways and included thickness of the different retinal layers, ganglion cells count, and immunohistochemistry for microglial cells, macroglial cells, and oligodendrocytes. The histological results indicate that IAA treatment does not affect the morphology of the inner retina and optic pathways. Electrophysiology confirms the selective rod and partial cone degeneration, but is ambiguous as to the functionality of the optic pathways, seemingly preserved as indicated by the still detectable fVEPs. Overall, the work ameliorates the characterization of such rapid and cost-effective model, providing more strength and reliability for future pre-clinical translational trials.
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Affiliation(s)
- Francesca Barone
- National Eye Institute, National Institute of Health, 10 Center Dr, Bethesda, 20814, MD, USA; Ophthalmology Department, Sacro Cuore Hospital - Don Calabria, Via Don A. Sempreboni 5, Negrar, 37024, VR, Italy
| | - Luisa Vera Muscatello
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Domenico Ventrella
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy.
| | - Alberto Elmi
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Noemi Romagnoli
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Luciana Mandrioli
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Josè Fernando Maya-Vetencourt
- Center for Synaptic Neuroscience and Technology, Italian Institute of Technology, Via Morego 30, Genova, 16163, GE, Italy; Department of Biology, University of Pisa, Via Alessandro Volta 4Bis, Pisa, 56126, PI, Italy
| | - Cristiano Bombardi
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Maurizio Mete
- Ophthalmology Department, Sacro Cuore Hospital - Don Calabria, Via Don A. Sempreboni 5, Negrar, 37024, VR, Italy
| | - Giuseppe Sarli
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Fabio Benfenati
- Center for Synaptic Neuroscience and Technology, Italian Institute of Technology, Via Morego 30, Genova, 16163, GE, Italy; Department of Experimental Medicine, University of Genoa, Via Leon Battista Alberti 2, Genova, 16132, GE, Italy
| | - Grazia Pertile
- Ophthalmology Department, Sacro Cuore Hospital - Don Calabria, Via Don A. Sempreboni 5, Negrar, 37024, VR, Italy
| | - Maria Laura Bacci
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
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11
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Petit L, Ma S, Cipi J, Cheng SY, Zieger M, Hay N, Punzo C. Aerobic Glycolysis Is Essential for Normal Rod Function and Controls Secondary Cone Death in Retinitis Pigmentosa. Cell Rep 2019; 23:2629-2642. [PMID: 29847794 PMCID: PMC5997286 DOI: 10.1016/j.celrep.2018.04.111] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 03/22/2018] [Accepted: 04/25/2018] [Indexed: 02/06/2023] Open
Abstract
Aerobic glycolysis accounts for ~80%–90% of glucose used by adult photoreceptors (PRs); yet, the importance of aerobic glycolysis for PR function or survival remains unclear. Here, we further established the role of aerobic glycolysis in murine rod and cone PRs. We show that loss of hexokinase-2 (HK2), a key aerobic glycolysis enzyme, does not affect PR survival or structure but is required for normal rod function. Rods with HK2 loss increase their mitochondrial number, suggesting an adaptation to the inhibition of aerobic glycolysis. In contrast, cones adapt without increased mitochondrial number but require HK2 to adapt to metabolic stress conditions such as those encountered in retinitis pigmentosa, where the loss of rods causes a nutrient shortage in cones. The data support a model where aerobic glycolysis in PRs is not a necessity but rather a metabolic choice that maximizes PR function and adaptability to nutrient stress conditions.
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Affiliation(s)
- Lolita Petit
- Department of Ophthalmology and Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
| | - Shan Ma
- Department of Ophthalmology and Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
| | - Joris Cipi
- Department of Ophthalmology and Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
| | - Shun-Yun Cheng
- Department of Ophthalmology and Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
| | - Marina Zieger
- Division of Pulmonary Medicine, Department of Pediatrics, University of Massachusetts Medical School, Worcester, MA, USA
| | - Nissim Hay
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Claudio Punzo
- Department of Ophthalmology and Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA.
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12
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Elmi A, Ventrella D, Laghi L, Carnevali G, Zhu C, Pertile G, Barone F, Benfenati F, Bacci ML. 1H NMR Spectroscopy Characterization of Porcine Vitreous Humor in Physiological and Photoreceptor Degeneration Conditions. ACTA ACUST UNITED AC 2019; 60:741-747. [DOI: 10.1167/iovs.18-25675] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Alberto Elmi
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Domenico Ventrella
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Luca Laghi
- Centre of Foodomics, Department of Agro-Food Science and Technology, University of Bologna, Bologna, Italy
| | - Giacomo Carnevali
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Chenglin Zhu
- Centre of Foodomics, Department of Agro-Food Science and Technology, University of Bologna, Bologna, Italy
| | - Grazia Pertile
- Ophthalmology Department, Sacro Cuore Hospital - Don Calabria, Negrar, Italy
| | - Francesca Barone
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
- Ophthalmology Department, Sacro Cuore Hospital - Don Calabria, Negrar, Italy
| | - Fabio Benfenati
- Center for Synaptic Neuroscience and Technology, Italian Institute of Technology, Genoa, Italy
- Department of Experimental Medicine, University of Genoa, Genoa, Italy
| | - Maria Laura Bacci
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
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13
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Kim C, Lee M, Lee SU, Lee SJ. Electroretinography Changes in Feline Model of Iodoacetic Acid-induced Retinal Degeneration. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2019. [DOI: 10.3341/jkos.2019.60.12.1205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Changzoo Kim
- Department of Ophthalmology, Kosin University College of Medicine, Busan, Korea
| | - Myungshin Lee
- Department of Ophthalmology, Kosin University College of Medicine, Busan, Korea
- Department of Ophthalmology, Inje University College of Medicine, Busan, Korea
| | - Seung Uk Lee
- Department of Ophthalmology, Kosin University College of Medicine, Busan, Korea
| | - Sang Joon Lee
- Department of Ophthalmology, Kosin University College of Medicine, Busan, Korea
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14
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Barone F, Nannoni E, Elmi A, Lambertini C, Scorpio DG, Ventrella D, Vitali M, Maya-Vetencourt JF, Martelli G, Benfenati F, Bacci ML. Behavioral Assessment of Vision in Pigs. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE 2018; 57:350-356. [PMID: 29966544 DOI: 10.30802/aalas-jaalas-17-000163] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Swine (Sus scrofa) are often the 'gold standard' laboratory animal for ophthalmology research due to the anatomic and physiologic similarities between the porcine and human eye and retina. Despite the importance of this model, few tools for behavioral vision assessment in pigs are available. The aim of this study was to identify and validate a feasible and reproducible behavioral test to assess vision in a pig model of photoreceptor degeneration. In addition, a robust behavioral test will reduce stress and enhance enrichment by allowing animals opportunities for environmental exploration and by reducing the number of invasive experimental procedures. Two distinct behavioral approaches were tested: the obstacle-course test and temperament test. In the obstacle-course test, pigs were challenged (after an initial training period) to navigate a 10-object obstacle course; time and the number of collisions with the objects were recorded. In the temperament test, the time needed for pigs to complete 3 different tasks (human-approach, novel-object, and open-door tests) was recorded. The obstacle-course test revealed significant differences in time and number of collisions between swine with vision impairment and control animals, and the training period proved to be pivotal to avoid bias due to individual animal characteristics. In contrast, the temperament test was not altered by vision impairment but was validated to measure stress and behavioral alterations in laboratory pigs undergoing experimental procedures, thus achieving marked refinement of the study.
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Affiliation(s)
- Francesca Barone
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, Italy
| | - Eleonora Nannoni
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, Italy
| | - Alberto Elmi
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, Italy
| | - Carlotta Lambertini
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, Italy
| | - Diana Gerardi Scorpio
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - Domenico Ventrella
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, Italy;,
| | - Marika Vitali
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, Italy
| | - José F Maya-Vetencourt
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genova, Italy
| | - Giovanna Martelli
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, Italy
| | - Fabio Benfenati
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genova, Italy
| | - Maria L Bacci
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, Italy
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15
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Kelly K, Wang JJ, Zhang SX. The unfolded protein response signaling and retinal Müller cell metabolism. Neural Regen Res 2018; 13:1861-1870. [PMID: 30233053 PMCID: PMC6183030 DOI: 10.4103/1673-5374.239431] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The retina is one of the most energy demanding tissues in the body. Like most neurons in the central nervous system, retinal neurons consume high amounts of adenosine-5'-triphosphate (ATP) to generate visual signal and transmit the information to the brain. Disruptions in retinal metabolism can cause neuronal dysfunction and degeneration resulting in severe visual impairment and even blindness. The homeostasis of retinal metabolism is tightly controlled by multiple signaling pathways, such as the unfolded protein response (UPR), and the close interactions between retinal neurons and other retinal cell types including vascular cells and Müller glia. The UPR is a highly conserved adaptive cellular response and can be triggered by many physiological stressors and pathophysiological conditions. Activation of the UPR leads to changes in glycolytic rate, ATP production, de novo serine synthesis, and the hexosamine biosynthetic pathway, which are considered critical components of Müller glia metabolism and provide metabolic support to surrounding neurons. When these pathways are disrupted, neurodegeneration occurs rapidly. In this review, we summarize recent advance in studies of the UPR in Müller glia and highlight the potential role of the UPR in retinal degeneration through regulation of Müller glia metabolism.
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Affiliation(s)
- Kristen Kelly
- Department of Ophthalmology and Neuroscience Program, Ross Eye Institute, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Joshua J Wang
- Department of Ophthalmology and Neuroscience Program, Ross Eye Institute, University at Buffalo; SUNY Eye Institute, State University of New York, Buffalo, NY, USA
| | - Sarah X Zhang
- Department of Ophthalmology and Neuroscience Program, Ross Eye Institute, University at Buffalo; SUNY Eye Institute, State University of New York, Buffalo, NY, USA
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16
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Kaplan HJ, Wang W, Dean DC. Restoration of Cone Photoreceptor Function in Retinitis Pigmentosa. Transl Vis Sci Technol 2017; 6:5. [PMID: 28900578 PMCID: PMC5588910 DOI: 10.1167/tvst.6.5.5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Accepted: 07/17/2017] [Indexed: 01/12/2023] Open
Affiliation(s)
- Henry J Kaplan
- University of Louisville, Department of Ophthalmology and Visual Sciences, Louisville, KY, USA
| | - Wei Wang
- University of Louisville, Department of Ophthalmology and Visual Sciences, Louisville, KY, USA
| | - Douglas C Dean
- University of Louisville, Department of Ophthalmology and Visual Sciences, Louisville, KY, USA.,University of Louisville, Molecular Targets Program, James Graham Brown Cancer Center, Louisville, KY, USA
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17
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Combes RD, Shah AB. The use of in vivo, ex vivo, in vitro, computational models and volunteer studies in vision research and therapy, and their contribution to the Three Rs. Altern Lab Anim 2017; 44:187-238. [PMID: 27494623 DOI: 10.1177/026119291604400302] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Much is known about mammalian vision, and considerable progress has been achieved in treating many vision disorders, especially those due to changes in the eye, by using various therapeutic methods, including stem cell and gene therapy. While cells and tissues from the main parts of the eye and the visual cortex (VC) can be maintained in culture, and many computer models exist, the current non-animal approaches are severely limiting in the study of visual perception and retinotopic imaging. Some of the early studies with cats and non-human primates (NHPs) are controversial for animal welfare reasons and are of questionable clinical relevance, particularly with respect to the treatment of amblyopia. More recently, the UK Home Office records have shown that attention is now more focused on rodents, especially the mouse. This is likely to be due to the perceived need for genetically-altered animals, rather than to knowledge of the similarities and differences of vision in cats, NHPs and rodents, and the fact that the same techniques can be used for all of the species. We discuss the advantages and limitations of animal and non-animal methods for vision research, and assess their relative contributions to basic knowledge and clinical practice, as well as outlining the opportunities they offer for implementing the principles of the Three Rs (Replacement, Reduction and Refinement).
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Affiliation(s)
| | - Atul B Shah
- Ophthalmic Surgeon, National Eye Registry Ltd, Leicester, UK
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18
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Photoreceptor degeneration by intravitreal injection of N-methyl-N-nitrosourea (MNU) in rabbits: a pilot study. Graefes Arch Clin Exp Ophthalmol 2016; 255:317-331. [PMID: 27866331 DOI: 10.1007/s00417-016-3531-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 09/13/2016] [Accepted: 10/17/2016] [Indexed: 10/20/2022] Open
Abstract
BACKGROUND Pilot study on the attempt to induce selective photoreceptor degeneration in the rabbit eye by intravitreal injection of MNU, facing the difficulties of the evaluation of retinal degeneration by different in-vivo and in-vitro methods in such a large eye animal model. METHODS Eight pigmented Chinchilla Bastard rabbits were injected intravitreally with MNU (1 × 1mg/kg body weight (BW), 1 × 2mg/kg BW, 3 × 3mg/kg BW, 1 × 4mg/kg BW, 1 × 6mg/kg BW, and 1 × DMSO + PBS as control). One, 2, and 3 weeks after injection, the effects on the rabbit retina were examined in vivo using clinical observation (macroscopic images, funduscopy, weighing of the animals), measurement of intraocular pressure (IOP), full-field Electroretinography (ffERG), and spectral-domain Optical Coherence Tomography (sd-OCT). After 3 weeks follow-up, blood samples were taken to evaluate the general health status of the animals, and immunohistochemistry (IH) was performed on sections obtained from six different regions throughout the whole retina to evaluate MNU effects in more detail. RESULTS It was difficult to observe the effects of MNU on retinal structure by OCT in vivo. Only the temporal quadrant of the retina could be visualized. Therefore, it was indispensible to evaluate the effects of MNU on the retina in vitro by examining six areas of the retina using immunohistochemistry. Furthermore, immunohistochemistry plays a decisive role to evaluate the effects on retinal cells other than photoreceptors while in H&E staining, namely the cell count of the ONL can be observed. The results obtained in vivo and in vitro in this study mainly follow the results of a previous study in mice. The low doses of MNU (1, 2 mg/kg BW) had no effects on retinal function and morphology, while high doses (4, 6 mg/kg BW) led to retinal changes in combination with significant side-effects (e.g., cataractous changes). Injection of 3 mg/kg BW MNU induced selective photoreceptor degeneration. However, the degree of degeneration varied between different parts of the same retina and between retinae of different animals. In two of three animals, a complete loss of ERG potentials was observed. Negative effects on the contralateral eye or on general welfare of the animal were never observed. CONCLUSIONS In rabbits, the intravitreal injection of 3 mg/kg BW MNU leads to selective but inhomogeneous photoreceptor degeneration.
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19
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Guadagni V, Cerri C, Piano I, Novelli E, Gargini C, Fiorentini C, Caleo M, Strettoi E. The bacterial toxin CNF1 as a tool to induce retinal degeneration reminiscent of retinitis pigmentosa. Sci Rep 2016; 6:35919. [PMID: 27775019 PMCID: PMC5075935 DOI: 10.1038/srep35919] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 10/04/2016] [Indexed: 12/02/2022] Open
Abstract
Retinitis pigmentosa (RP) comprises a group of inherited pathologies characterized by progressive photoreceptor degeneration. In rodent models of RP, expression of defective genes and retinal degeneration usually manifest during the first weeks of postnatal life, making it difficult to distinguish consequences of primary genetic defects from abnormalities in retinal development. Moreover, mouse eyes are small and not always adequate to test pharmacological and surgical treatments. An inducible paradigm of retinal degeneration potentially extensible to large animals is therefore desirable. Starting from the serendipitous observation that intraocular injections of a Rho GTPase activator, the bacterial toxin Cytotoxic Necrotizing Factor 1 (CNF1), lead to retinal degeneration, we implemented an inducible model recapitulating most of the key features of Retinitis Pigmentosa. The model also unmasks an intrinsic vulnerability of photoreceptors to the mechanism of CNF1 action, indicating still unexplored molecular pathways potentially leading to the death of these cells in inherited forms of retinal degeneration.
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Affiliation(s)
- Viviana Guadagni
- Neuroscience Institute, Italian National Research Council (CNR), Pisa, 56124, Italy
| | - Chiara Cerri
- Neuroscience Institute, Italian National Research Council (CNR), Pisa, 56124, Italy.,Accademia dei Lincei, Rome, 00165, Italy
| | - Ilaria Piano
- Department of Pharmacy, University of Pisa, Pisa, 56126, Italy
| | - Elena Novelli
- Neuroscience Institute, Italian National Research Council (CNR), Pisa, 56124, Italy
| | - Claudia Gargini
- Department of Pharmacy, University of Pisa, Pisa, 56126, Italy
| | | | - Matteo Caleo
- Neuroscience Institute, Italian National Research Council (CNR), Pisa, 56124, Italy
| | - Enrica Strettoi
- Neuroscience Institute, Italian National Research Council (CNR), Pisa, 56124, Italy
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20
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Rueda EM, Johnson JE, Giddabasappa A, Swaroop A, Brooks MJ, Sigel I, Chaney SY, Fox DA. The cellular and compartmental profile of mouse retinal glycolysis, tricarboxylic acid cycle, oxidative phosphorylation, and ~P transferring kinases. Mol Vis 2016; 22:847-85. [PMID: 27499608 PMCID: PMC4961465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Accepted: 07/21/2016] [Indexed: 10/26/2022] Open
Abstract
PURPOSE The homeostatic regulation of cellular ATP is achieved by the coordinated activity of ATP utilization, synthesis, and buffering. Glucose is the major substrate for ATP synthesis through glycolysis and oxidative phosphorylation (OXPHOS), whereas intermediary metabolism through the tricarboxylic acid (TCA) cycle utilizes non-glucose-derived monocarboxylates, amino acids, and alpha ketoacids to support mitochondrial ATP and GTP synthesis. Cellular ATP is buffered by specialized equilibrium-driven high-energy phosphate (~P) transferring kinases. Our goals were twofold: 1) to characterize the gene expression, protein expression, and activity of key synthesizing and regulating enzymes of energy metabolism in the whole mouse retina, retinal compartments, and/or cells and 2) to provide an integrative analysis of the results related to function. METHODS mRNA expression data of energy-related genes were extracted from our whole retinal Affymetrix microarray data. Fixed-frozen retinas from adult C57BL/6N mice were used for immunohistochemistry, laser scanning confocal microscopy, and enzymatic histochemistry. The immunoreactivity levels of well-characterized antibodies, for all major retinal cells and their compartments, were obtained using our established semiquantitative confocal and imaging techniques. Quantitative cytochrome oxidase (COX) and lactate dehydrogenase (LDH) activity was determined histochemically. RESULTS The Affymetrix data revealed varied gene expression patterns of the ATP synthesizing and regulating enzymes found in the muscle, liver, and brain. Confocal studies showed differential cellular and compartmental distribution of isozymes involved in glucose, glutamate, glutamine, lactate, and creatine metabolism. The pattern and intensity of the antibodies and of the COX and LDH activity showed the high capacity of photoreceptors for aerobic glycolysis and OXPHOS. Competition assays with pyruvate revealed that LDH-5 was localized in the photoreceptor inner segments. The combined results indicate that glycolysis is regulated by the compartmental expression of hexokinase 2, pyruvate kinase M1, and pyruvate kinase M2 in photoreceptors, whereas the inner retinal neurons exhibit a lower capacity for glycolysis and aerobic glycolysis. Expression of nucleoside diphosphate kinase, mitochondria-associated adenylate kinase, and several mitochondria-associated creatine kinase isozymes was highest in the outer retina, whereas expression of cytosolic adenylate kinase and brain creatine kinase was higher in the cones, horizontal cells, and amacrine cells indicating the diversity of ATP-buffering strategies among retinal neurons. Based on the antibody intensities and the COX and LDH activity, Müller glial cells (MGCs) had the lowest capacity for glycolysis, aerobic glycolysis, and OXPHOS. However, they showed high expression of glutamate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinate thiokinase, GABA transaminase, and ~P transferring kinases. This suggests that MGCs utilize TCA cycle anaplerosis and cataplerosis to generate GTP and ~P transferring kinases to produce ATP that supports MGC energy requirements. CONCLUSIONS Our comprehensive and integrated results reveal that the adult mouse retina expresses numerous isoforms of ATP synthesizing, regulating, and buffering genes; expresses differential cellular and compartmental levels of glycolytic, OXPHOS, TCA cycle, and ~P transferring kinase proteins; and exhibits differential layer-by-layer LDH and COX activity. New insights into cell-specific and compartmental ATP and GTP production, as well as utilization and buffering strategies and their relationship with known retinal and cellular functions, are discussed. Developing therapeutic strategies for neuroprotection and treating retinal deficits and degeneration in a cell-specific manner will require such knowledge. This work provides a platform for future research directed at identifying the molecular targets and proteins that regulate these processes.
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Affiliation(s)
- Elda M. Rueda
- College of Optometry, University of Houston, Houston TX
| | - Jerry E. Johnson
- Department of Natural Sciences, University of Houston-Downtown, Houston TX
- Department of Biology and Biochemistry, University of Houston, Houston TX
| | - Anand Giddabasappa
- Department of Biology and Biochemistry, University of Houston, Houston TX
| | | | | | - Irena Sigel
- College of Optometry, University of Houston, Houston TX
| | - Shawnta Y. Chaney
- Department of Biology and Biochemistry, University of Houston, Houston TX
| | - Donald A. Fox
- College of Optometry, University of Houston, Houston TX
- Department of Biology and Biochemistry, University of Houston, Houston TX
- Department of Pharmacology and Pharmaceutical Sciences, University of Houston, Houston TX
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21
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Wang W, Lee SJ, Scott PA, Lu X, Emery D, Liu Y, Ezashi T, Roberts MR, Ross JW, Kaplan HJ, Dean DC. Two-Step Reactivation of Dormant Cones in Retinitis Pigmentosa. Cell Rep 2016; 15:372-85. [PMID: 27050517 DOI: 10.1016/j.celrep.2016.03.022] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 02/02/2016] [Accepted: 03/04/2016] [Indexed: 01/01/2023] Open
Abstract
Most retinitis pigmentosa (RP) mutations arise in rod photoreceptor genes, leading to diminished peripheral and nighttime vision. Using a pig model of autosomal-dominant RP, we show glucose becomes sequestered in the retinal pigment epithelium (RPE) and, thus, is not transported to photoreceptors. The resulting starvation for glucose metabolites impairs synthesis of cone visual pigment-rich outer segments (OSs), and then their mitochondrial-rich inner segments dissociate. Loss of these functional structures diminishes cone-dependent high-resolution central vision, which is utilized for most daily tasks. By transplanting wild-type rods, to restore glucose transport, or directly replacing glucose in the subretinal space, to bypass its retention in the RPE, we can regenerate cone functional structures, reactivating the dormant cells. Beyond providing metabolic building blocks for cone functional structures, we show glucose induces thioredoxin-interacting protein (Txnip) to regulate Akt signaling, thereby shunting metabolites toward aerobic glucose metabolism and regenerating cone OS synthesis.
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Affiliation(s)
- Wei Wang
- Department of Ophthalmology & Visual Sciences, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Sang Joon Lee
- Department of Ophthalmology & Visual Sciences, University of Louisville Health Sciences Center, Louisville, KY 40202, USA; Department of Ophthalmology, College of Medicine, Kosin University, Busan, South Korea
| | - Patrick A Scott
- Department of Ophthalmology & Visual Sciences, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Xiaoqin Lu
- Department of Ophthalmology & Visual Sciences, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Douglas Emery
- Department of Ophthalmology & Visual Sciences, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Yongqin Liu
- Department of Ophthalmology & Visual Sciences, University of Louisville Health Sciences Center, Louisville, KY 40202, USA; Birth Defects Center, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Toshihiko Ezashi
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Michael R Roberts
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Jason W Ross
- Department of Animal Sciences, Iowa State University, Ames, IA 50011, USA
| | - Henry J Kaplan
- Department of Ophthalmology & Visual Sciences, University of Louisville Health Sciences Center, Louisville, KY 40202, USA
| | - Douglas C Dean
- Department of Ophthalmology & Visual Sciences, University of Louisville Health Sciences Center, Louisville, KY 40202, USA; Molecular Targets Program, James Graham Brown Cancer Center, University of Louisville Health Sciences Center, Louisville, KY 40202, USA; Birth Defects Center, University of Louisville Health Sciences Center, Louisville, KY 40202, USA.
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22
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Vessey KA, Greferath U, Aplin FP, Jobling AI, Phipps JA, Ho T, De Iongh RU, Fletcher EL. Adenosine triphosphate-induced photoreceptor death and retinal remodeling in rats. J Comp Neurol 2014; 522:2928-50. [PMID: 24639102 PMCID: PMC4265795 DOI: 10.1002/cne.23558] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 02/06/2014] [Accepted: 02/07/2014] [Indexed: 02/06/2023]
Abstract
Many common causes of blindness involve the death of retinal photoreceptors, followed by progressive inner retinal cell remodeling. For an inducible model of retinal degeneration to be useful, it must recapitulate these changes. Intravitreal administration of adenosine triphosphate (ATP) has recently been found to induce acute photoreceptor death. The aim of this study was to characterize the chronic effects of ATP on retinal integrity. Five-week-old, dark agouti rats were administered 50 mM ATP into the vitreous of one eye and saline into the other. Vision was assessed using the electroretinogram and optokinetic response and retinal morphology investigated via histology. ATP caused significant loss of visual function within 1 day and loss of 50% of the photoreceptors within 1 week. At 3 months, 80% of photoreceptor nuclei were lost, and total photoreceptor loss occurred by 6 months. The degeneration and remodeling were similar to those found in heritable retinal dystrophies and age-related macular degeneration and included inner retinal neuronal loss, migration, and formation of new synapses; Müller cell gliosis, migration, and scarring; blood vessel loss; and retinal pigment epithelium migration. In addition, extreme degeneration and remodeling events, such as neuronal and glial migration outside the neural retina and proliferative changes in glial cells, were observed. These extreme changes were also observed in the 2-year-old P23H rhodopsin transgenic rat model of retinitis pigmentosa. This ATP-induced model of retinal degeneration may provide a valuable tool for developing pharmaceutical therapies or for testing electronic implants aimed at restoring vision.
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Affiliation(s)
- Kirstan A Vessey
- Department of Anatomy and Neuroscience, The University of Melbourne,Melbourne, Victoria, 3010, Australia
| | - Ursula Greferath
- Department of Anatomy and Neuroscience, The University of Melbourne,Melbourne, Victoria, 3010, Australia
| | - Felix P Aplin
- Department of Anatomy and Neuroscience, The University of Melbourne,Melbourne, Victoria, 3010, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital,East Melbourne, Victoria, 3002, Australia
- The Bionics Institute,East Melbourne, Victoria, 3002, Australia
| | - Andrew I Jobling
- Department of Anatomy and Neuroscience, The University of Melbourne,Melbourne, Victoria, 3010, Australia
| | - Joanna A Phipps
- Department of Anatomy and Neuroscience, The University of Melbourne,Melbourne, Victoria, 3010, Australia
| | - Tracy Ho
- Department of Anatomy and Neuroscience, The University of Melbourne,Melbourne, Victoria, 3010, Australia
| | - Robbert U De Iongh
- Department of Anatomy and Neuroscience, The University of Melbourne,Melbourne, Victoria, 3010, Australia
| | - Erica L Fletcher
- Department of Anatomy and Neuroscience, The University of Melbourne,Melbourne, Victoria, 3010, Australia
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23
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The effects of iodoacetic acid on the mouse retina. Graefes Arch Clin Exp Ophthalmol 2014; 253:25-35. [PMID: 24827634 DOI: 10.1007/s00417-014-2652-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 03/12/2014] [Accepted: 04/16/2014] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND To characterize the effects of intravitreal injections of iodoacetic acid (IAA) in comparison to its systemic application as a measure to induce unilateral photoreceptor degeneration. METHODS Seven-week-old C57BL/6 J mice received either intravitreal injections of IAA or systemic treatment (intraperitoneal vs intravenous) and were observed in the following 5 weeks using ERG, OCT, and histology. RESULTS Systemic treatment with IAA induced high toxic effects and a high mortality in contrast to the intravitreal injection. Intraperitoneal application had no effect on the retina. Intravenous application of 2 × 30 mg/kg BW IAA (time between injections 3.5 h) resulted in an extinction of the ERG and a thinning of the retina, in particular of the outer nuclear layer (ONL) indicating photoreceptor degeneration. Animals receiving intravitreal injections developed cataracts already at low concentrations (up to 100% at 0.25 mg/kg BW). Higher intravitreal IAA doses led to extinguished ERGs. In histology, a thinning of the entire retina was observed that was most prominent in the inner part of the retina. CONCLUSIONS In contrast to intraperitoneal administration, intravenous application of IAA led to a selective photoreceptor degeneration. After intravitreal injection, dense cataracts were already observed at concentrations lower than those needed to induce changes in the ERG. ERG results must be interpreted carefully. A thinning of all retinal layers rather than a specific outer retinal degeneration was observed upon intravitreal injection. IAA is not a useful model to induce outer retinal degeneration in mice.
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24
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Wang W, Zhou L, Lee SJ, Liu Y, Fernandez de Castro J, Emery D, Vukmanic E, Kaplan HJ, Dean DC. Swine cone and rod precursors arise sequentially and display sequential and transient integration and differentiation potential following transplantation. Invest Ophthalmol Vis Sci 2014; 55:301-9. [PMID: 24327609 DOI: 10.1167/iovs.13-12600] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE We followed cone and rod development in the pig and we correlated development with the potential for cone and rod precursor integration and differentiation following subretinal transplantation. METHODS Rod and cone precursors were identified during development by their position in the outer retina and by immunostaining for markers of differentiation. Embryonic retinal cells from green fluorescent protein (GFP)(+) transgenic pigs at different developmental stages were transplanted into adult retinas and integration and differentiation was followed and quantified by immunostaining for markers of cone and rod differentiation. RESULTS Pig cones and rods are spatially segregated, allowing us to follow rod and cone development in situ. Gestation in the pig is 114 days. By embryonic day (E) 50, postmitotic cone progenitors had formed the outer two rows of the retina. These cone progenitors are marked by expression of Islet1 (ISL1) and Recoverin (RCVRN) (at this embryonic stage, RCVRN exclusively marks these cone precursors). By contrast, postmitotic neural retina leucine zipper (NRL)(+) rod precursors, located interior to the cone precursors, did not appear until E65. At E50, before NRL(+) rod precursors are evident, transplanted cells gave rise almost exclusively to cones. At, E57, transplanted cells gave rise to equal numbers of rods and cones, but by E65, transplanted cells gave rise almost exclusively to rods. Transplantation of cells at E85 or E105, as precursors initiate opsin expression, led to few integrated cells. CONCLUSIONS Consistent with their sequential appearances in embryonic retina, these results demonstrate sequential and surprisingly narrow developmental windows for integration/differentiation of cone and rod precursors following transplantation.
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Affiliation(s)
- Wei Wang
- Department of Ophthalmology and Visual Sciences, University of Louisville Health Sciences Center, Louisville, Kentucky
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25
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Karl MO. The potential of stem cell research for the treatment of neuronal damage in glaucoma. Cell Tissue Res 2013; 353:311-25. [PMID: 23708526 DOI: 10.1007/s00441-013-1646-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 04/23/2013] [Indexed: 01/29/2023]
Abstract
Stem cell research offers a wide variety of approaches for the advancement of our understanding of basic mechanisms of neurodegeneration and tissue regeneration and for the discovery and development of new therapeutic strategies to prevent and restore neuronal cell loss. Similar to most other regions of our central nervous system, degenerative diseases of the retina lead to the loss of neurons, which are not replaced. Recent work in animals has provided proof-of-concept evidence for the restoration of photoreceptor cells by cell transplantation and neuronal cell replacement by regeneration from endogenous cell sources. However, efficient therapeutic prevention of neuronal cell loss has not been achieved. Moreover, successful cell replacement of retinal neurons in humans, including that of ganglion cells, remains a major challenge. Future successes in the discovery and translation of neuroprotective drug and gene therapies and of cell-based regenerative therapies will depend on a better understanding of the underlying disease pathomechanisms. Existing stem cell and cell-reprogramming technologies offer the potential to generate human retina cells, to develop specific human-cell-based retina disease models, and to open up novel therapeutic strategies. Further, we might glean substantial knowledge from species that can or cannot regenerate their neuronal retina, in the search for new therapeutic approaches. Thus, stem cell research will pave the way toward clinical translation. In this review, I address some of the major possibilities presently on offer and speculate about the power of stem cell research to gain further insights into the pathomechanisms of retinal neurodegeneration (with special emphasis on glaucoma) and to advance our therapeutic options.
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Affiliation(s)
- Mike O Karl
- German Center for Neurodegenerative Diseases e.V. (DZNE), Arnoldstrasse 18/18b, 01307, Dresden, Germany.
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26
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Nan Y, Zhang Q, Ren C, Huang X, Gao J, Li X, Pu M. Functional evaluation of iodoacetic acid induced photoreceptor degeneration in the cat. SCIENCE CHINA-LIFE SCIENCES 2013; 56:524-30. [PMID: 23657794 DOI: 10.1007/s11427-013-4483-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 04/10/2013] [Indexed: 10/26/2022]
Abstract
Iodoacetic acid (IAA) has been applied to different species to acutely induce photoreceptor degeneration. The purpose of the present study was to use this toxin to thoroughly eliminate photoreceptors and induce complete blindness in the cat. IAA was delivered by single ear vein injection (20 mg kg(-1)). Six months after the IAA treatment, functional evaluations including pupillary light reflex (PLR), electroretinogram (ERG), visual behavior tests were performed. Morphological examinations were carried out after the functional evaluation. The present result shows that, six months after the IAA application, animals lost visual functions and became completely blind. High dose IAA application via ear vein delivery created an acute and reliable complete photoreceptor degeneration model in the cat. This model can be applied to genetic and cellular therapies for visual function restoration.
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Affiliation(s)
- Yan Nan
- Department of Anatomy/Embryology, School of Basic Medical Sciences, Peking University, Beijing 100191, China
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27
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Prather RS, Lorson M, Ross JW, Whyte JJ, Walters E. Genetically engineered pig models for human diseases. Annu Rev Anim Biosci 2013; 1:203-19. [PMID: 25387017 DOI: 10.1146/annurev-animal-031412-103715] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Although pigs are used widely as models of human disease, their utility as models has been enhanced by genetic engineering. Initially, transgenes were added randomly to the genome, but with the application of homologous recombination, zinc finger nucleases, and transcription activator-like effector nuclease (TALEN) technologies, now most any genetic change that can be envisioned can be completed. To date these genetic modifications have resulted in animals that have the potential to provide new insights into human diseases for which a good animal model did not exist previously. These new animal models should provide the preclinical data for treatments that are developed for diseases such as Alzheimer's disease, cystic fibrosis, retinitis pigmentosa, spinal muscular atrophy, diabetes, and organ failure. These new models will help to uncover aspects and treatments of these diseases that were otherwise unattainable. The focus of this review is to describe genetically engineered pigs that have resulted in models of human diseases.
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Affiliation(s)
- Randall S Prather
- Division of Animal Science, National Swine Resource and Research Center, and
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28
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Noel JM, Fernandez de Castro JP, DeMarco PJ, Franco LM, Wang W, Vukmanic EV, Peng X, Sandell JH, Scott PA, Kaplan HJ, McCall MA. Iodoacetic acid, but not sodium iodate, creates an inducible swine model of photoreceptor damage. Exp Eye Res 2012; 97:137-47. [PMID: 22251455 PMCID: PMC3323738 DOI: 10.1016/j.exer.2011.12.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 12/16/2011] [Accepted: 12/22/2011] [Indexed: 11/26/2022]
Abstract
Our purpose was to find a method to create a large animal model of inducible photoreceptor damage. To this end, we tested in domestic swine the efficacy of two chemical toxins, known to create photoreceptor damage in other species: Iodoacetic Acid (IAA) and Sodium Iodate (NaIO(3)). Intravenous (IV) administration of NaIO(3) up to 90 mg/kg had no effect on retinal function and 110 mg/kg was lethal. IV administration of IAA (5-20 mg/kg) produced concentration-dependent changes in visual function as measured by full-field and multi-focal electroretinograms (ffERG and mfERG), and 30 mg/kg IAA was lethal. The IAA-induced effects measured at two weeks were stable through eight weeks post-injection, the last time point investigated. IAA at 7.5, 10, and 12 mg/kg produce a concentration-dependent reduction in both ffERG b-wave and mfERG N1-P1 amplitudes compared to baseline at all post-injection times. Comparisons of dark- and light-adapted ffERG b-wave amplitudes show a more significant loss of rod relative to cone function. The fundus of swine treated with ≥10 mg/kg IAA was abnormal with thinner retinal vessels and pale optic discs, and we found no evidence of bone spicule formation. Histological evaluations show concentration-dependent outer retinal damage that correlates with functional changes. We conclude that NaIO(3,) is not an effective toxin in swine. In contrast, IAA can be used to create a rapidly inducible, selective, stable and concentration-dependent model of photoreceptor damage in swine retina. Because of these attributes this large animal model of controlled photoreceptor damage should be useful in the investigation of treatments to replace damaged photoreceptors.
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Affiliation(s)
- Jennifer M. Noel
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY
| | | | - Paul J. DeMarco
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
- Department of Psychological and Brain Sciences, University of Louisville, Louisville, KY
| | - Luisa M. Franco
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
| | - Wei Wang
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
| | - Eric V. Vukmanic
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
| | - Xiaoyan Peng
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
| | - Julie H. Sandell
- Department of Anatomy and Neurobiology, Boston University, Boston, MA
| | - Patrick A. Scott
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
- Department of Anatomy and Neurobiology, Boston University, Boston, MA
| | - Henry J. Kaplan
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
| | - Maureen A. McCall
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY
- Department of Psychological and Brain Sciences, University of Louisville, Louisville, KY
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