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Shechter Y, Cohen R, Namestnikov M, Shapira A, Barak A, Barzelay A, Dvir T. Sequential Fabrication of a Three-Layer Retina-like Structure. Gels 2024; 10:336. [PMID: 38786253 PMCID: PMC11121616 DOI: 10.3390/gels10050336] [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: 04/11/2024] [Revised: 04/24/2024] [Accepted: 05/12/2024] [Indexed: 05/25/2024] Open
Abstract
Tissue engineering is considered a promising approach to treating advanced degenerative maculopathies such as nonexudative age-related macular degeneration (AMD), the leading cause of blindness worldwide. The retina consists of several hierarchical tissue layers, each of which is supported by a layer underneath. Each of these layers has a different morphology and requires distinct conditions for proper assembly. In fact, a prerequisite step for the assembly of each of these layers is the organization of the layer underneath. Advanced retinal degeneration includes degeneration of the other retina layers, including the choroid, the retinal pigmented epithelium (RPE), and the photoreceptors. Here, we report a step-by-step fabrication process of a three-layer retina-like structure. The process included the 3D printing of a choroid-like structure in an extracellular matrix (ECM) hydrogel, followed by deposition of the RPE monolayer. After the formation of the blood vessel-RPE interface, the photoreceptor cells were deposited to interact with the RPE layer. At the end of the fabrication process, each layer was characterized for its morphology and expression of specific markers, and the integration of the three-layer retina was evaluated. We envision that such a retina-like structure may be able to attenuate the deterioration of a degenerated retina and improve engraftment and regeneration. This retinal implant may potentially be suitable for a spectrum of macular degenerative diseases for which there are currently no cures and may save millions from complete blindness.
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Affiliation(s)
- Yahel Shechter
- Shmunis School of Biomedicine and Cancer Research, Faculty of Life Science, Tel Aviv University, Tel Aviv 6997801, Israel; (Y.S.); (R.C.); (M.N.); (A.S.)
| | - Roni Cohen
- Shmunis School of Biomedicine and Cancer Research, Faculty of Life Science, Tel Aviv University, Tel Aviv 6997801, Israel; (Y.S.); (R.C.); (M.N.); (A.S.)
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 6997801, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Michael Namestnikov
- Shmunis School of Biomedicine and Cancer Research, Faculty of Life Science, Tel Aviv University, Tel Aviv 6997801, Israel; (Y.S.); (R.C.); (M.N.); (A.S.)
| | - Assaf Shapira
- Shmunis School of Biomedicine and Cancer Research, Faculty of Life Science, Tel Aviv University, Tel Aviv 6997801, Israel; (Y.S.); (R.C.); (M.N.); (A.S.)
| | - Adiel Barak
- Division of Ophthalmology, Tel Aviv Medical Center, Tel Aviv 6423906, Israel;
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Aya Barzelay
- Division of Ophthalmology, Tel Aviv Medical Center, Tel Aviv 6423906, Israel;
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Tal Dvir
- Shmunis School of Biomedicine and Cancer Research, Faculty of Life Science, Tel Aviv University, Tel Aviv 6997801, Israel; (Y.S.); (R.C.); (M.N.); (A.S.)
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 6997801, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
- The Center for Nanoscience and Nanotechnology, Tel Aviv University, Tel Aviv 6997801, Israel
- Sagol Center for Regenerative Biotechnology, Tel Aviv University, Tel Aviv 6997801, Israel
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2
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Ho MT, Kawai K, Abdo D, Comanita L, Ortin-Martinez A, Ueno Y, Tsao E, Rastgar-Moghadam A, Xue C, Cui H, Wallace VA, Shoichet MS. Transplanted human photoreceptors transfer cytoplasmic material but not to the recipient mouse retina. Stem Cell Res Ther 2024; 15:79. [PMID: 38486269 PMCID: PMC10941468 DOI: 10.1186/s13287-024-03679-3] [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: 11/24/2023] [Accepted: 02/21/2024] [Indexed: 03/17/2024] Open
Abstract
BACKGROUND The discovery of material transfer between transplanted and host mouse photoreceptors has expanded the possibilities for utilizing transplanted photoreceptors as potential vehicles for delivering therapeutic cargo. However, previous research has not directly explored the capacity for human photoreceptors to engage in material transfer, as human photoreceptor transplantation has primarily been investigated in rodent models of late-stage retinal disease, which lack host photoreceptors. METHODS In this study, we transplanted human stem-cell derived photoreceptors purified from human retinal organoids at different ontological ages (weeks 10, 14, or 20) into mouse models with intact photoreceptors and assessed transfer of human proteins and organelles to mouse photoreceptors. RESULTS Unexpectedly, regardless of donor age or mouse recipient background, human photoreceptors did not transfer material in the mouse retina, though a rare subset of donor cells (< 5%) integrated into the mouse photoreceptor cell layer. To investigate the possibility that a species barrier impeded transfer, we used a flow cytometric assay to examine material transfer in vitro. Interestingly, dissociated human photoreceptors transferred fluorescent protein with each other in vitro, yet no transfer was detected in co-cultures of human and mouse photoreceptors, suggesting that material transfer is species specific. CONCLUSIONS While xenograft models are not a tractable system to study material transfer of human photoreceptors, these findings demonstrate that human retinal organoid-derived photoreceptors are competent donors for material transfer and thus may be useful to treat retinal degenerative disease.
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Affiliation(s)
- Margaret T Ho
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E2, Canada
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, 60 Leonard Ave, Toronto, ON, M5T 2S8, Canada
| | - Kotoe Kawai
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
- Regenerative Medicine Research and Planning Division, Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa, Kyoto, 619-0216, Japan
| | - Dhana Abdo
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E2, Canada
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Lacrimioara Comanita
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, 60 Leonard Ave, Toronto, ON, M5T 2S8, Canada
| | - Arturo Ortin-Martinez
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, 60 Leonard Ave, Toronto, ON, M5T 2S8, Canada
| | - Yui Ueno
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E2, Canada
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
- Regenerative Medicine Research and Planning Division, Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa, Kyoto, 619-0216, Japan
| | - Emily Tsao
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E2, Canada
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Azam Rastgar-Moghadam
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, 60 Leonard Ave, Toronto, ON, M5T 2S8, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Chang Xue
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E2, Canada
| | - Hong Cui
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E2, Canada
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Valerie A Wallace
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, 60 Leonard Ave, Toronto, ON, M5T 2S8, Canada.
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada.
| | - Molly S Shoichet
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada.
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, Toronto, ON, M5S 3E2, Canada.
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada.
- Department of Chemistry, University of Toronto, Toronto, ON, Canada.
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Michelis G, German OL, Villasmil R, Soto T, Rotstein NP, Politi L, Becerra SP. Pigment epithelium-derived factor (PEDF) and derived peptides promote survival and differentiation of photoreceptors and induce neurite-outgrowth in amacrine neurons. J Neurochem 2021; 159:840-856. [PMID: 34133756 DOI: 10.1111/jnc.15454] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 06/11/2021] [Accepted: 06/15/2021] [Indexed: 12/16/2022]
Abstract
Pigment epithelium-derived factor (PEDF) is a cytoprotective protein for the retina. We hypothesize that this protein acts on neuronal survival and differentiation of photoreceptor cells in culture. The purpose of the present study was to evaluate the neurotrophic effects of PEDF and its fragments in an in vitro model of cultured primary retinal neurons that die spontaneously in the absence of trophic factors. We used Wistar albino rats. Cell death was assayed by immunofluorescence and flow cytometry through TUNEL assay, propidium iodide, mitotracker, and annexin V. Immunofluorescence of cells for visualizing rhodopsin, CRX, and antisyntaxin under confocal microscopy was performed. Neurite outgrowth was also quantified. Results show that PEDF protected photoreceptor precursors from apoptosis, preserved mitochondrial function and promoted polarization of opsin enhancing their developmental process, as well as induced neurite outgrowth in amacrine neurons. These effects were abolished by an inhibitor of the PEDF receptor or receptor-derived peptides that block ligand/receptor interactions. While all the activities were specifically conferred by short peptide fragments (17 amino acid residues) derived from the PEDF neurotrophic domain, no effects were triggered by peptides from the PEDF antiangiogenic region. The observed effects on retinal neurons imply a specific activation of the PEDF receptor by a small neurotrophic region of PEDF. Our findings support the neurotrophic PEDF peptides as neuronal guardians for the retina, highlighting their potential as promoters of retinal differentiation, and inhibitors of retinal cell death and its blinding consequences.
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Affiliation(s)
- Germán Michelis
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute - National Institutes of Health, Bethesda, MD, USA.,Department of Biology, Pharmacy and Biochemistry, Instituto de Investigaciones Bioquímicas (INIBIBB), Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
| | - Olga Lorena German
- Department of Biology, Pharmacy and Biochemistry, Instituto de Investigaciones Bioquímicas (INIBIBB), Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
| | - Rafael Villasmil
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute - National Institutes of Health, Bethesda, MD, USA
| | - Tamara Soto
- Department of Biology, Pharmacy and Biochemistry, Instituto de Investigaciones Bioquímicas (INIBIBB), Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
| | - Nora P Rotstein
- Department of Biology, Pharmacy and Biochemistry, Instituto de Investigaciones Bioquímicas (INIBIBB), Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
| | - Luis Politi
- Department of Biology, Pharmacy and Biochemistry, Instituto de Investigaciones Bioquímicas (INIBIBB), Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Argentina
| | - S Patricia Becerra
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute - National Institutes of Health, Bethesda, MD, USA
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Forouzanfar F, Shojapour M, Aghili ZS, Asgharzade S. Growth Factors as Tools in Photoreceptor Cell Regeneration and Vision Recovery. Curr Drug Targets 2021; 21:573-581. [PMID: 31755378 DOI: 10.2174/1389450120666191121103831] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 10/04/2019] [Accepted: 10/18/2019] [Indexed: 02/08/2023]
Abstract
Photoreceptor loss is a major cause of blindness around the world. Stem cell therapy offers a new strategy in retina degenerative disease. Retinal progenitors can be derived from embryonic stem cells (ESC) in vitro, but cannot be processed to a mature state. In addition, the adult recipient retina presents a very different environment than the photoreceptor precursor donor. It seems that modulation of the recipient environment by ectopic development regulated growth factors for transplanted cells could generate efficient putative photoreceptors. The purpose of this review article was to investigate the signaling pathway of growth factors including: insulin-like growth factors (IGFs), fibroblast growth factors (FGF), Nerve growth factor (NGF), Brain-derived neurotrophic factor (BDNF), Taurin and Retinoic acid (RA) involved in the differentiation of neuroretina cell, like; photoreceptor and retinal progenitor cells. Given the results available in the related literature, the differentiation efficacy of ESCs toward the photoreceptor and retinal neurons and the important role of growth factors in activating signaling pathways such as Akt, Ras/Raf1/ and ERKs also inhibit the ASK1/JNK apoptosis pathway. Manipulating differentiated culture, growth factors can influence photoreceptor transplantation efficiency in retinal degenerative disease.
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Affiliation(s)
- Fatemeh Forouzanfar
- Neuroscience Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Neuroscience, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mana Shojapour
- Molecular and Medicine Research Center, Arak University of Medical Sciences, Arak, Iran
| | - Zahra Sadat Aghili
- Cellular and Molecular Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Samira Asgharzade
- Cellular and Molecular Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
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5
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FGFR4 c.1162G > A (p.Gly388Arg) Polymorphism Analysis in Turkish Patients with Retinoblastoma. JOURNAL OF ONCOLOGY 2021; 2020:9401038. [PMID: 33456465 PMCID: PMC7787726 DOI: 10.1155/2020/9401038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 12/16/2020] [Indexed: 12/31/2022]
Abstract
Purpose Various molecular variations are known to result in different gene variants in the FGFR4 gene, known for its oncogenic transformation activity. The goal of this study was to investigate the FGFR4 p.Gly388Arg variant that plays role in the progression of cancer and retinal growth and may be an effective candidate variant in the Turkish population in retinoblastoma patients with no RB1 gene mutation. Methods Using the Sanger sequencing methods, the FGFR4 p.Gly388Arg variant was bidirectionally sequenced in 49 patients with non-RB1 gene mutation in retinoblastoma patients and 13 healthy first-degree relatives and 146 individuals matched by sex and age in the control group. Results In Turkish population-specific study, the FGFR4 p.Gly388Arg variant was found in 27 (55.1 percent) of 49 patients; mutation was found in 7 (53.8 percent) of these patients' 13 healthy relatives screened. When FGFR4 p.Gly388Arg mutation status is evaluated in terms of 146 healthy controls, in 70 (47.9 percent) individuals, mutation was observed. Our analysis showed that the FGFR4 p.Gly388Arg allele frequency, which according to different databases is seen as 30 percent in the general population, is 50 percent common in the Turkish population. Conclusions In patients with advanced retinoblastoma who were diagnosed with retinoblastoma prior to 24 months, the FGFR4 p.Gly388Arg allele was found to be significantly higher. As a result, these results indicate that the polymorphism of FGFR4 p.Gly388Arg may play a role in both the development of tumors and the progression of aggressive tumors.
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Jemni-Damer N, Guedan-Duran A, Fuentes-Andion M, Serrano-Bengoechea N, Alfageme-Lopez N, Armada-Maresca F, Guinea GV, Perez-Rigueiro J, Rojo F, Gonzalez-Nieto D, Kaplan DL, Panetsos F. Biotechnology and Biomaterial-Based Therapeutic Strategies for Age-Related Macular Degeneration. Part II: Cell and Tissue Engineering Therapies. Front Bioeng Biotechnol 2020; 8:588014. [PMID: 33363125 PMCID: PMC7758210 DOI: 10.3389/fbioe.2020.588014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 11/19/2020] [Indexed: 12/12/2022] Open
Abstract
Age-related Macular Degeneration (AMD) is an up-to-date untreatable chronic neurodegenerative eye disease of multifactorial origin, and the main causes of blindness in over 65 y.o. people. It is characterized by a slow progression and the presence of a multitude of factors, highlighting those related to diet, genetic heritage and environmental conditions, present throughout each of the stages of the illness. Current therapeutic approaches, mainly consisting on intraocular drug delivery, are only used for symptoms relief and/or to decelerate the progression of the disease. Furthermore, they are overly simplistic and ignore the complexity of the disease and the enormous differences in the symptomatology between patients. Due to the wide impact of the AMD and the up-to-date absence of clinical solutions, Due to the wide impact of the AMD and the up-to-date absence of clinical solutions, different treatment options have to be considered. Cell therapy is a very promising alternative to drug-based approaches for AMD treatment. Cells delivered to the affected tissue as a suspension have shown poor retention and low survival rate. A solution to these inconveniences has been the encapsulation of these cells on biomaterials, which contrive to their protection, gives them support, and favor their retention of the desired area. We offer a two-papers critical review of the available and under development AMD therapeutic approaches, from a biomaterials and biotechnological point of view. We highlight benefits and limitations and we forecast forthcoming alternatives based on novel biomaterials and biotechnology methods. In this second part we review the preclinical and clinical cell-replacement approaches aiming at the development of efficient AMD-therapies, the employed cell types, as well as the cell-encapsulation and cell-implant systems. We discuss their advantages and disadvantages and how they could improve the survival and integration of the implanted cells.
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Affiliation(s)
- Nahla Jemni-Damer
- Neuro-computing and Neuro-robotics Research Group, Complutense University of Madrid, Madrid, Spain
- Innovation Group, Institute for Health Research San Carlos Clinical Hospital, Madrid, Spain
| | - Atocha Guedan-Duran
- Neuro-computing and Neuro-robotics Research Group, Complutense University of Madrid, Madrid, Spain
- Innovation Group, Institute for Health Research San Carlos Clinical Hospital, Madrid, Spain
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - María Fuentes-Andion
- Neuro-computing and Neuro-robotics Research Group, Complutense University of Madrid, Madrid, Spain
- Innovation Group, Institute for Health Research San Carlos Clinical Hospital, Madrid, Spain
| | - Nora Serrano-Bengoechea
- Neuro-computing and Neuro-robotics Research Group, Complutense University of Madrid, Madrid, Spain
- Innovation Group, Institute for Health Research San Carlos Clinical Hospital, Madrid, Spain
- Silk Biomed SL, Madrid, Spain
| | - Nuria Alfageme-Lopez
- Neuro-computing and Neuro-robotics Research Group, Complutense University of Madrid, Madrid, Spain
- Innovation Group, Institute for Health Research San Carlos Clinical Hospital, Madrid, Spain
- Silk Biomed SL, Madrid, Spain
| | | | - Gustavo V. Guinea
- Silk Biomed SL, Madrid, Spain
- Center for Biomedical Technology, Universidad Politécnica de Madrid, Pozuelo de Alarcon, Spain
- Department of Material Science, Civil Engineering Superior School, Universidad Politécnica de Madrid, Madrid, Spain
- Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, Madrid, Spain
| | - José Perez-Rigueiro
- Silk Biomed SL, Madrid, Spain
- Center for Biomedical Technology, Universidad Politécnica de Madrid, Pozuelo de Alarcon, Spain
- Department of Material Science, Civil Engineering Superior School, Universidad Politécnica de Madrid, Madrid, Spain
- Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, Madrid, Spain
| | - Francisco Rojo
- Silk Biomed SL, Madrid, Spain
- Center for Biomedical Technology, Universidad Politécnica de Madrid, Pozuelo de Alarcon, Spain
- Department of Material Science, Civil Engineering Superior School, Universidad Politécnica de Madrid, Madrid, Spain
- Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, Madrid, Spain
| | - Daniel Gonzalez-Nieto
- Silk Biomed SL, Madrid, Spain
- Center for Biomedical Technology, Universidad Politécnica de Madrid, Pozuelo de Alarcon, Spain
- Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, Madrid, Spain
| | - David L. Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Fivos Panetsos
- Neuro-computing and Neuro-robotics Research Group, Complutense University of Madrid, Madrid, Spain
- Innovation Group, Institute for Health Research San Carlos Clinical Hospital, Madrid, Spain
- Silk Biomed SL, Madrid, Spain
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7
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Hurst J, Fietz A, Tsai T, Joachim SC, Schnichels S. Organ Cultures for Retinal Diseases. Front Neurosci 2020; 14:583392. [PMID: 33324149 PMCID: PMC7724035 DOI: 10.3389/fnins.2020.583392] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/13/2020] [Indexed: 12/18/2022] Open
Abstract
The successful development of novel therapies is closely linked with understanding the underlying pathomechanisms of a disease. To do so, model systems that reflect human diseases and allow for the evaluation of new therapeutic approaches are needed. Yet, preclinical animal studies often have limited success in predicting human physiology, pathology, and therapeutic responses. Moreover, animal testing is facing increasing ethical and bureaucratic hurdles, while human cell cultures are limited in their ability to represent in vivo situations due to the lack of the tissue microenvironment, which may alter cellular responses. To overcome these struggles, organ cultures, especially those of complex organs such as the retina, can be used to study physiological reactions to substances or stressors. Human and animal organ cultures are now well established and recognized. This mini-review discusses how retinal organ cultures can be used to preserve tissue architecture more realistically and therefore better represent disease-related changes. It also shows how molecular biological, biochemical, and histological techniques can be combined to investigate how anatomical localization may alter cellular responses. Examples for the use of retinal organ cultures, including models to study age-related macular degeneration (AMD), retinitis pigmentosa (RP), central artery occlusion (CRAO), and glaucoma are presented, and their advantages and disadvantages are discussed. We conclude that organ cultures significantly improve our understanding of complex retinal diseases and may advance treatment testing without the need for animal testing.
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Affiliation(s)
- José Hurst
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Agnes Fietz
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Teresa Tsai
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Stephanie C Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Sven Schnichels
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
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8
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Singh RK, Nasonkin IO. Limitations and Promise of Retinal Tissue From Human Pluripotent Stem Cells for Developing Therapies of Blindness. Front Cell Neurosci 2020; 14:179. [PMID: 33132839 PMCID: PMC7513806 DOI: 10.3389/fncel.2020.00179] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 05/25/2020] [Indexed: 12/13/2022] Open
Abstract
The self-formation of retinal tissue from pluripotent stem cells generated a tremendous promise for developing new therapies of retinal degenerative diseases, which previously seemed unattainable. Together with use of induced pluripotent stem cells or/and CRISPR-based recombineering the retinal organoid technology provided an avenue for developing models of human retinal degenerative diseases "in a dish" for studying the pathology, delineating the mechanisms and also establishing a platform for large-scale drug screening. At the same time, retinal organoids, highly resembling developing human fetal retinal tissue, are viewed as source of multipotential retinal progenitors, young photoreceptors and just the whole retinal tissue, which may be transplanted into the subretinal space with a goal of replacing patient's degenerated retina with a new retinal "patch." Both approaches (transplantation and modeling/drug screening) were projected when Yoshiki Sasai demonstrated the feasibility of deriving mammalian retinal tissue from pluripotent stem cells, and generated a lot of excitement. With further work and testing of both approaches in vitro and in vivo, a major implicit limitation has become apparent pretty quickly: the absence of the uniform layer of Retinal Pigment Epithelium (RPE) cells, which is normally present in mammalian retina, surrounds photoreceptor layer and develops and matures first. The RPE layer polarize into apical and basal sides during development and establish microvilli on the apical side, interacting with photoreceptors, nurturing photoreceptor outer segments and participating in the visual cycle by recycling 11-trans retinal (bleached pigment) back to 11-cis retinal. Retinal organoids, however, either do not have RPE layer or carry patches of RPE mostly on one side, thus directly exposing most photoreceptors in the developing organoids to neural medium. Recreation of the critical retinal niche between the apical RPE and photoreceptors, where many retinal disease mechanisms originate, is so far unattainable, imposes clear limitations on both modeling/drug screening and transplantation approaches and is a focus of investigation in many labs. Here we dissect different retinal degenerative diseases and analyze how and where retinal organoid technology can contribute the most to developing therapies even with a current limitation and absence of long and functional outer segments, supported by RPE.
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9
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Schnichels S, Paquet-Durand F, Löscher M, Tsai T, Hurst J, Joachim SC, Klettner A. Retina in a dish: Cell cultures, retinal explants and animal models for common diseases of the retina. Prog Retin Eye Res 2020; 81:100880. [PMID: 32721458 DOI: 10.1016/j.preteyeres.2020.100880] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 06/23/2020] [Accepted: 06/26/2020] [Indexed: 12/11/2022]
Abstract
For many retinal diseases, including age-related macular degeneration (AMD), glaucoma, and diabetic retinopathy (DR), the exact pathogenesis is still unclear. Moreover, the currently available therapeutic options are often unsatisfactory. Research designed to remedy this situation heavily relies on experimental animals. However, animal models often do not faithfully reproduce human disease and, currently, there is strong pressure from society to reduce animal research. Overall, this creates a need for improved disease models to understand pathologies and develop treatment options that, at the same time, require fewer or no experimental animals. Here, we review recent advances in the field of in vitro and ex vivo models for AMD, glaucoma, and DR. We highlight the difficulties associated with studies on complex diseases, in which both the initial trigger and the ensuing pathomechanisms are unclear, and then delineate which model systems are optimal for disease modelling. To this end, we present a variety of model systems, ranging from primary cell cultures, over organotypic cultures and whole eye cultures, to animal models. Specific advantages and disadvantages of such models are discussed, with a special focus on their relevance to putative in vivo disease mechanisms. In many cases, a replacement of in vivo research will mean that several different in vitro models are used in conjunction, for instance to analyze and validate causative molecular pathways. Finally, we argue that the analytical decomposition into appropriate cell and tissue model systems will allow making significant progress in our understanding of complex retinal diseases and may furthermore advance the treatment testing.
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Affiliation(s)
- Sven Schnichels
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Germany.
| | - François Paquet-Durand
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Germany
| | - Marina Löscher
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Germany
| | - Teresa Tsai
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Germany
| | - José Hurst
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Germany
| | - Stephanie C Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Germany
| | - Alexa Klettner
- Department of Ophthalmology, University Medical Center, University of Kiel, Kiel, Germany
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Lewejohann L, Pallerla SR, Schreiber RS, Gerula J, Grobe K. Cerebellar Morphology and Behavioral Profiles in Mice Lacking Heparan Sulfate Ndst Gene Function. J Dev Biol 2020; 8:jdb8030013. [PMID: 32664575 PMCID: PMC7560088 DOI: 10.3390/jdb8030013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 07/06/2020] [Accepted: 07/09/2020] [Indexed: 11/16/2022] Open
Abstract
Disruption of the Heparan sulfate (HS)-biosynthetic gene N-acetylglucosamine N-Deacetylase/N-sulfotransferase 1 (Ndst1) during nervous system development causes malformations that are composites of those caused by mutations of multiple HS binding growth factors and morphogens. However, the role of Ndst function in adult brain physiology is less explored. Therefore, we generated mice bearing a Purkinje-cell-specific deletion in Ndst1 gene function by using Cre/loxP technology under the control of the Purkinje cell protein 2 (Pcp2/L7) promotor, which results in HS undersulfation. We observed that mutant mice did not show overt changes in the density or organization of Purkinje cells in the adult cerebellum, and behavioral tests also demonstrated normal cerebellar function. This suggested that postnatal Purkinje cell development and homeostasis are independent of Ndst1 function, or that impaired HS sulfation upon deletion of Ndst1 function may be compensated for by other Purkinje cell-expressed Ndst isoforms. To test the latter possibility, we additionally deleted the second Purkinje-cell expressed Ndst family member, Ndst2. This selectively abolished reproductive capacity of compound mutant female, but not male, mice, suggesting that ovulation, gestation, or female reproductive behavior specifically depends on Ndst-dependent HS sulfation in cells types that express Cre under Pcp2/L7 promotor control.
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Affiliation(s)
- Lars Lewejohann
- Department of Behavioral Biology, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany; (L.L.); (R.S.S.); (J.G.)
| | - Srinivas R. Pallerla
- Institute of Tropical Medicine, University of Tübingen, 72074 Tübingen, Germany;
| | - Rebecca S. Schreiber
- Department of Behavioral Biology, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany; (L.L.); (R.S.S.); (J.G.)
| | - Joanna Gerula
- Department of Behavioral Biology, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany; (L.L.); (R.S.S.); (J.G.)
| | - Kay Grobe
- Institute of Physiological Chemistry and Pathobiochemistry, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
- Correspondence: ; Tel.: +49-251-83-52289
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Che L, Song JY, Lou Y, Li GY. Analysis from the perspective of cilia: the protective effect of PARP inhibitors on visual function during light-induced damage. Int Ophthalmol 2019; 40:1017-1027. [PMID: 31802371 DOI: 10.1007/s10792-019-01245-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 11/23/2019] [Indexed: 12/26/2022]
Abstract
PURPOSE To analyze the protective effect of PARP inhibitors on light-damaged retina and explore its possible mechanism from the perspective of ciliopathy. METHODS A systematic review of the literature was performed to investigate the protection of PARP inhibition on light-damaged cilia. PubMed database was retrieved to find the relevant studies and 119 literatures were involved in the review. RESULTS In retina, the outer segment of photoreceptor is regarded as a special type of primary cilium, so various retinal diseases actually belong to a type of ciliopathy. The retina is the only central nervous tissue exposed to light, but poly (ADP-ribose) polymerase (PARP), as a nuclear enzyme repairing DNA breaks, is overactivated during the light-induced DNA damage, and is involved in the cell death cascade. Studies show that both ATR and phosphorylated Akt colocalize with cilium and play an important role in regulating ciliary function. PARP may function at ATR or PI3K/Akt signal to exert protective effect on cilia. CONCLUSION PARP inhibitors may protect the cilia/OS of photoreceptor during light-induced damage, which the possible mechanism may be involved in the activation of ATR and PI3K/Akt signal.
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Affiliation(s)
- Lin Che
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China
| | - Jing-Yao Song
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China
| | - Yan Lou
- Department of Nephropathy, Second Hospital of Jilin University, Changchun, 130041, China
| | - Guang-Yu Li
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China.
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IGF-1 and IGF-1R modulate the effects of IL-4 on retinal ganglion cells survival: The involvement of M1 muscarinic receptor. Biochem Biophys Res Commun 2019; 519:53-60. [PMID: 31474338 DOI: 10.1016/j.bbrc.2019.08.124] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 08/23/2019] [Indexed: 11/22/2022]
Abstract
Trophic factors are involved in different cellular responses. Previously we demonstrated that IL-4 treatment induces an increase in retinal ganglion cell survival (RGCS) and regulates cholinergic differentiation of retinal cells in vitro. Data from literature show that IGF-1 also promotes RGCS, an effect mediated by PI-3K/AKT pathway. The aim of this study was to investigate the role of IGF-1 and IGF-1R on RGCS mediated by IL-4 treatment and the role of M1 acetylcholine receptors in this effect. Here we show that the effect of IL-4 on RGCS depends on IGF-1 and IGF-1R activation, the PI-3K/AKT and NFkB intracellular pathways and depends on M1 mAChRs activation. IGF-1 increases the levels of M1 mAChRs in 15min, 45min, 24 h and 48 h in mixed retinal cells culture, modulates the levels of IL-4, pIGF-1R, IGF-1R. IL-4 modulates IGF-1, pIGF-1R and IGF-1R levels in different time intervals. These results put in evidence a crosstalk between IL-4 and IGF-1 and a role of M1 mAChRs, IGF-1 and IGF-1R in RGCS mediated by IL-4.
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Appelbaum T, Santana E, Aguirre GD. Strong upregulation of inflammatory genes accompanies photoreceptor demise in canine models of retinal degeneration. PLoS One 2017; 12:e0177224. [PMID: 28486508 PMCID: PMC5423635 DOI: 10.1371/journal.pone.0177224] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 04/24/2017] [Indexed: 01/18/2023] Open
Abstract
We have analyzed the complex pattern of the inflammatory response in early-onset canine models of human retinitis pigmentosa, rcd1, xlpra2 and erd, as well as late-onset xlpra1, in comparative manner. The time course of immune response genes and proteins expression was examined along the timeline of photoreceptors degeneration. Gene expression analysis of the early-onset models prior to and after the peak of photoreceptors death identified the involvement of multiple immune response genes including those encoding constituents of the NLRP3 inflammasome, its substrates, pro-IL1B, pro-IL18, and common components of IL1B, IL18 and TLR4 pathways. Out of two activated caspase-1 cleavage products, IL1B and IL18, only IL1B was detected in rcd1 and xlpra2 while precursor IL18 remained unprocessed in the same protein extract highlighting prominence of IL1B pathway. An overall immune response was most prominent in rcd1 followed by xlpra2 and least prominent in erd. Noticeably, in rcd1 and xlpra2, but not in erd, early induction of the immune response was accompanied by sustained intraretinal migration and activation of retinal microglia. Lastly, delayed activation of the anti-inflammatory factors in all early-onset models was insufficient to counterbalance rapidly progressing inflammation. In contrast to early-onset models, in late-onset xlpra1 retinas a subset of the pro-inflammatory genes was highly upregulated long before any disease-related structural changes occurred, but was counterbalanced by an adequate anti-inflammatory response. Results point out to upregulated immune response accompanying disease progression in animal models of retinal degeneration, and to potential benefits of early anti-inflammatory therapy.
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Affiliation(s)
- Tatyana Appelbaum
- Section of Ophthalmology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Evelyn Santana
- Section of Ophthalmology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Gustavo D. Aguirre
- Section of Ophthalmology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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German OL, Agnolazza DL, Politi LE, Rotstein NP. Light, lipids and photoreceptor survival: live or let die? Photochem Photobiol Sci 2015. [PMID: 26204250 DOI: 10.1039/c5pp00194c] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Due to its constant exposure to light and its high oxygen consumption the retina is highly sensitive to oxidative damage, which is a common factor in inducing the death of photoreceptors after light damage or in inherited retinal degenerations. The high content of docosahexaenoic acid (DHA), the major polyunsaturated fatty acid in the retina, has been suggested to contribute to this sensitivity. DHA is crucial for developing and preserving normal visual function. However, further roles of DHA in the retina are still controversial. Current data support that it can tilt the scale either towards degeneration or survival of retinal cells. DHA peroxidation products can be deleterious to the retina and might lead to retinal degeneration. However, DHA has also been shown to act as, or to be the source of, a survival molecule that protects photoreceptors and retinal pigment epithelium cells from oxidative damage. We have established that DHA protects photoreceptors from oxidative stress-induced apoptosis and promotes their differentiation in vitro. DHA activates the retinoid X receptor (RXR) and the ERK/MAPK pathway, thus regulating the expression of anti and pro-apoptotic proteins. It also orchestrates a diversity of signaling pathways, modulating enzymatic pathways that control the sphingolipid metabolism and activate antioxidant defense mechanisms to promote photoreceptor survival and development. A deeper comprehension of DHA signaling pathways and context-dependent behavior is required to understand its dual functions in retinal physiology.
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Affiliation(s)
- Olga Lorena German
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Buenos Aires, Argentina.
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Jaeger C, Sandu C, Malan A, Mellac K, Hicks D, Felder‐Schmittbuhl M. Circadian organization of the rodent retina involves strongly coupled, layer‐specific oscillators. FASEB J 2015; 29:1493-504. [DOI: 10.1096/fj.14-261214] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 12/02/2014] [Indexed: 11/11/2022]
Affiliation(s)
- Catherine Jaeger
- Department of Neurobiology of RhythmsInstitute for Cellular and Integrative NeurosciencesNational Center for Scientific Research UPR3212University of StrasbourgStrasbourgFrance
| | - Cristina Sandu
- Department of Neurobiology of RhythmsInstitute for Cellular and Integrative NeurosciencesNational Center for Scientific Research UPR3212University of StrasbourgStrasbourgFrance
| | - André Malan
- Department of Neurobiology of RhythmsInstitute for Cellular and Integrative NeurosciencesNational Center for Scientific Research UPR3212University of StrasbourgStrasbourgFrance
| | - Katell Mellac
- Unit of Mathematics and Computer ScienceUniversity of StrasbourgStrasbourgFrance
| | - David Hicks
- Department of Neurobiology of RhythmsInstitute for Cellular and Integrative NeurosciencesNational Center for Scientific Research UPR3212University of StrasbourgStrasbourgFrance
| | - Marie‐Paule Felder‐Schmittbuhl
- Department of Neurobiology of RhythmsInstitute for Cellular and Integrative NeurosciencesNational Center for Scientific Research UPR3212University of StrasbourgStrasbourgFrance
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Abed E, Corbo G, Falsini B. Neurotrophin Family Members as Neuroprotectants in Retinal Degenerations. BioDrugs 2014; 29:1-13. [DOI: 10.1007/s40259-014-0110-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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18
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The (Na(+)/K (+))-ATPase activity in the developing rat retina: the role of insulin-like growth factor-I (IGF-I). Cell Mol Neurobiol 2014; 35:243-54. [PMID: 25274047 DOI: 10.1007/s10571-014-0119-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 09/23/2014] [Indexed: 02/04/2023]
Abstract
In this work, the (Na(+)/K(+))-ATPase activity was evaluated during the early stages of the postnatal development of rat retina and showed an almost three-time increase from P0 to P14. Expression of the three catalytic subunit isoforms (α1, α2, and α3) of the (Na(+)/K(+))-ATPase was also evaluated by immunoblot in the same period, but no correlation to the catalytic activity increment was observed. On the other hand, immunolocalization of these three α-catalytic isoforms in the developing retina showed an age-related pattern. Involvement of IGF-I in the stimulation of the (Na(+)/K(+))-ATPase was investigated. Our results demonstrate that the exogenous IGF-I (10 ng/mL) stimulates enzyme activity at the age of P7 only. Incubation of retinas with 10 μM I-OMe-AG 538 (inhibitor of the IGF-I receptor) indicates that the basal (Na(+)/K(+))-ATPase activity is sustained by endogenous IGF-I in P7 animals. These data were corroborated by an age-dependent decrease in the immunodetection of endogenous IGF-I as well as in the phosphorylation level of its cognate receptor in rat retina homogenates. The signaling pathway involved in IGF-I-induced modulation of the (Na(+)/K(+))-ATPase was also investigated. Our data show that the inhibitory effects induced by I-OMe-AG 538 and the PI 3-kinase inhibitor Ly 294002 on the basal (Na(+)/K(+))-ATPase activity were non-cumulative. Furthermore, IGF-I induced phosphorylation of PKB in a Ly 294002-sensitive manner. Together, these data demonstrate that the PI 3-kinase/PKB signaling pathway is involved in the IGF-I-sustained basal (Na(+)/K(+))-ATPase activity during the first 7 days of the postnatal development of rat retina.
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Trophic factors in the pathogenesis and therapy for retinal degenerative diseases. Surv Ophthalmol 2014; 59:134-65. [PMID: 24417953 DOI: 10.1016/j.survophthal.2013.09.004] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 09/11/2013] [Accepted: 09/17/2013] [Indexed: 12/27/2022]
Abstract
Trophic factors are endogenously secreted proteins that act in an autocrine and/or paracrine fashion to affect vital cellular processes such as proliferation, differentiation, and regeneration, thereby maintaining overall cell homeostasis. In the eye, the major contributors of these molecules are the retinal pigment epithelial (RPE) and Müller cells. The primary paracrine targets of these secreted proteins include the photoreceptors and choriocapillaris. Retinal degenerative diseases such as age-related macular degeneration and retinitis pigmentosa are characterized by aberrant function and/or eventual death of RPE cells, photoreceptors, choriocapillaris, and other retinal cells. We discuss results of in vitro and in vivo animal studies in which candidate trophic factors, either singly or in combination, were used in an attempt to ameliorate photoreceptor and/or retinal degeneration. We also examine current trophic factor therapies as they relate to the treatment of retinal degenerative diseases in clinical studies.
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20
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Willardsen M, Hutcheson DA, Moore KB, Vetter ML. The ETS transcription factor Etv1 mediates FGF signaling to initiate proneural gene expression during Xenopus laevis retinal development. Mech Dev 2013; 131:57-67. [PMID: 24219979 DOI: 10.1016/j.mod.2013.10.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 09/27/2013] [Accepted: 10/25/2013] [Indexed: 11/28/2022]
Abstract
Fibroblast growth factor signaling plays a significant role in the developing eye, regulating both patterning and neurogenesis. Members of the Pea3/Etv4-subfamily of ETS-domain transcription factors (Etv1, Etv4, and Etv5) are transcriptional activators that are downstream targets of FGF/MAPK signaling, but whether they are required for eye development is unknown. We show that in the developing Xenopus laevis retina, etv1 is transiently expressed at the onset of retinal neurogenesis. We found that etv1 is not required for eye specification, but is required for the expression of atonal-related proneural bHLH transcription factors, and is also required for retinal neuron differentiation. Using transgenic reporters we show that the distal atoh7 enhancer, which is required for the initiation of atoh7 expression in the Xenopus retina, is responsive to both FGF signaling and etv1 expression. Thus, we conclude that Etv1 acts downstream of FGF signaling to regulate the initiation of neurogenesis in the Xenopus retina.
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Affiliation(s)
- Minde Willardsen
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - David A Hutcheson
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Kathryn B Moore
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Monica L Vetter
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
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Basic fibroblast growth factor expression is implicated in mesenchymal stem cells response to light-induced retinal injury. Cell Mol Neurobiol 2013; 33:1171-9. [PMID: 24030359 DOI: 10.1007/s10571-013-9983-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 08/31/2013] [Indexed: 12/29/2022]
Abstract
Neurotrophic factors are involved in neuroprotection and its expression in mesenchymal stem cells (MSCs) may change during light-induced retinal injury. In this study, neurotrophic factor expression in MSCs was investigated after stimulation by supernatants of homogenized retina (SHR) from normal and light-injured rats. Conditioned media from control MSCs (CM-MSCs), MSCs stimulated by normal SHR (CM-NSHR), and MSCs stimulated by light-injured SHR (CM-ISHR) were examined regarding their ability to prevent degeneration of retinal explants. Basic fibroblast growth factor (bFGF) in MSCs was knockdown by lentivirus-mediated mRNA interference. Transfected MSCs were stimulated by SHR, and retinal preservation was reevaluated in the resultant conditioned media. We detected significant up-regulation of bFGF in CM-ISHR, accompanied by superior retinal neurotrophic effects in CM-ISHR over CM-NSHR and CM-MSCs. Down-regulation of bFGF in MSCs effectively inhibited this protective effect. Adding neutralizing antibody against bFGF to CM-ISHR also induced a similar effect. It is thus concluded that retinal injury may enhance neurotrophic factor expression in MSCs and promote the repair process. bFGF may play a critical role in MSCs' response to retinal injury.
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Changes in fibroblast growth factor-2 and FGF receptors in the frog visual system during optic nerve regeneration. J Chem Neuroanat 2012; 46:35-44. [PMID: 22940608 DOI: 10.1016/j.jchemneu.2012.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 08/15/2012] [Accepted: 08/16/2012] [Indexed: 02/02/2023]
Abstract
We have previously shown that application of fibroblast growth factor-2 (FGF-2) to cut optic nerve axons enhances retinal ganglion cell (RGC) survival in the adult frog visual system. These actions are mediated via activation of its high affinity receptor FGFR1, enhanced BDNF and TrkB expression, increased CREB phosphorylation, and by promoting MAPK and PKA signaling pathways. The role of endogenous FGF-2 in this system is less well understood. In this study, we determine the distribution of FGF-2 and its receptors in normal animals and in animals at different times after optic nerve cut. Immunohistochemistry and Western blot analysis were conducted using specific antibodies against FGF-2 and its receptors in control retinas and optic tecta, and after one, three, and six weeks post nerve injury. FGF-2 was transiently increased in the retina while it was reduced in the optic tectum just one week after optic nerve transection. Axotomy induced a prolonged upregulation of FGFR1 and FGFR3 in both retina and tectum. FGFR4 levels decreased in the retina shortly after axotomy, whereas a significant increase was detected in the optic tectum. FGFR2 distribution was not affected by the optic nerve lesion. Changes in the presence of these proteins after axotomy suggest a potential role during regeneration.
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Abstract
In retinal diseases characterized by photoreceptor degeneration, the main cause of clinically significant vision loss is cone, rather than rod, loss. Photoreceptor apoptosis can be affected by the availability and/or delivery of neurotrophic proteins, and cultures of photoreceptors are valuable for studying these processes. In the present study, a technique was designed to purify cones to make it possible to screen for neuroprotective molecules. The present chapter describes a technique for preparing cultures of purified rat retina cone photoreceptors based upon panning with peanut agglutinin lectin, which selectively binds to cones. In addition, we describe a protocol for the purification and culture of retinal pigmented epithelial cells from postnatal rat.
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Hochmann S, Kaslin J, Hans S, Weber A, Machate A, Geffarth M, Funk RHW, Brand M. Fgf signaling is required for photoreceptor maintenance in the adult zebrafish retina. PLoS One 2012; 7:e30365. [PMID: 22291943 PMCID: PMC3266925 DOI: 10.1371/journal.pone.0030365] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 12/19/2011] [Indexed: 11/19/2022] Open
Abstract
Fibroblast growth factors (Fgf) are secreted signaling molecules that have mitogenic, patterning, neurotrophic and angiogenic properties. Their importance during embryonic development in patterning and morphogenesis of the vertebrate eye is well known, but less is known about the role of Fgfs in the adult vertebrate retina. To address Fgf function in adult retina, we determined the spatial distribution of components of the Fgf signaling pathway in the adult zebrafish retina. We detected differential expression of Fgf receptors, ligands and downstream Fgf targets within specific retinal layers. Furthermore, we blocked Fgf signaling in the retina, by expressing a dominant negative variant of Fgf receptor 1 conditionally in transgenic animals. After blocking Fgf signaling we observe a fast and progressive photoreceptor degeneration and disorganization of retinal tissue, coupled with cell death in the outer nuclear layer. Following the degeneration of photoreceptors, a profound regeneration response is triggered that starts with proliferation in the inner nuclear layer. Ultimately, rod and cone photoreceptors are regenerated completely. Our study reveals the requirement of Fgf signaling to maintain photoreceptors and for proliferation during regeneration in the adult zebrafish retina.
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MESH Headings
- Age Factors
- Animals
- Animals, Genetically Modified
- Cell Death/genetics
- Cell Death/physiology
- Cell Survival/genetics
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/metabolism
- Fibroblast Growth Factors/physiology
- Gene Expression Regulation, Developmental
- Photoreceptor Cells, Vertebrate/metabolism
- Photoreceptor Cells, Vertebrate/physiology
- Receptor, Fibroblast Growth Factor, Type 1/genetics
- Receptor, Fibroblast Growth Factor, Type 1/metabolism
- Receptors, Fibroblast Growth Factor/genetics
- Receptors, Fibroblast Growth Factor/metabolism
- Receptors, Fibroblast Growth Factor/physiology
- Retina/cytology
- Retina/metabolism
- Retina/physiology
- Signal Transduction/genetics
- Signal Transduction/physiology
- Zebrafish/genetics
- Zebrafish/growth & development
- Zebrafish/metabolism
- Zebrafish/physiology
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Affiliation(s)
- Sarah Hochmann
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence (CRTD), Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Jan Kaslin
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence (CRTD), Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Stefan Hans
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence (CRTD), Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Anke Weber
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence (CRTD), Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Anja Machate
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence (CRTD), Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Michaela Geffarth
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence (CRTD), Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Richard H. W. Funk
- Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Michael Brand
- DFG-Center for Regenerative Therapies Dresden, Cluster of Excellence (CRTD), Biotechnology Center, Technische Universität Dresden, Dresden, Germany
- * E-mail:
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Guduric-Fuchs J, Chen W, Price H, Archer DB, Cogliati T. RPE and neuronal differentiation of allotransplantated porcine ciliary epithelium-derived cells. Mol Vis 2011; 17:2580-95. [PMID: 22025893 PMCID: PMC3198501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Accepted: 10/02/2011] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Cell replacement has the potential to be applied as a therapeutic strategy in retinal degenerative diseases such as retinitis pigmentosa and age-related macular degeneration (AMD) for which no adequate pharmacological and surgical treatments are currently available. Although controversial, the use of ciliary epithelium (CE)-derived cells is supported by evidence showing their differentiation into retinal phenotypes. This study examines the differentiation potential of porcine CE-derived cells in vitro and their survival, migration, morphological characteristics, and immunohistochemical phenotype in vivo, upon transplantation into the subretinal space of normal pigs. METHODS Cells were isolated from the CE of postnatal pigs and were grown in a suspension sphere culture. Differentiation was assessed in vitro after exposure to laminin and the addition of serum. For transplantation, CE-derived spheres were dissociated, labeled with CM-DiI vital dye, and the cells were injected subretinally into one eye of eight week-old allorecipients. The eyes were examined at eight days and at two and four weeks after transplantation. RESULTS Cells positive for neuronal and retinal pigment epithelium (RPE) markers were detected by immunohistochemistry in differentiation cultures. Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) revealed upregulation of neuronal markers after in vitro differentiation. CM-DiI dye-labeled CE-derived cells dissociated from primary spheres survived for up to four weeks after transplantation in vivo. Some of the surviving cells migrated distantly from the injection site. Large clusters of transplanted cells integrated into the RPE layer and multilayered RPE-like structures positive for RPE65 were often observed. Grafted cells were also identified in the neuroretina where 5%-10% were positive for recoverin, protein kinase C alpha (PKCα), and calbindin. CONCLUSIONS The efficient conversion to an RPE-like phenotype suggests that CE-derived cells could be a potential source of RPE for cell replacement. Our data also suggest that the ability of these cells to acquire neuronal phenotypes is influenced by the environment. Thus, pre-differentiated or (re)programmed CE-derived cells may be more amenable for retinal repair.
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Affiliation(s)
- Jasenka Guduric-Fuchs
- Centre for Vision and Vascular Sciences, Queen’s University Belfast, Royal Victoria Hospital, Institute of Clinical Science, Northern Ireland, UK
| | - Wing Chen
- Royal Victoria Hospital, Grosvenor Road, Belfast, Northern Ireland, UK
| | - Henrietta Price
- The Agri-Food and Biosciences Institute (AFBI), Chemical Surveillance Branch, Veterinary Sciences Division, Stoney Road, Stormont, Belfast, Northern Ireland UK
| | - Desmond B. Archer
- Centre for Vision and Vascular Sciences, Queen’s University Belfast, Royal Victoria Hospital, Institute of Clinical Science, Northern Ireland, UK
| | - Tiziana Cogliati
- Centre for Vision and Vascular Sciences, Queen’s University Belfast, Royal Victoria Hospital, Institute of Clinical Science, Northern Ireland, UK
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Simón MV, De Genaro P, Abrahan CE, de los Santos B, Rotstein NP, Politi LE. Müller glial cells induce stem cell properties in retinal progenitors in vitro and promote their further differentiation into photoreceptors. J Neurosci Res 2011; 90:407-21. [DOI: 10.1002/jnr.22747] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 06/18/2011] [Accepted: 06/21/2011] [Indexed: 01/12/2023]
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Sandu C, Hicks D, Felder-Schmittbuhl MP. Rat photoreceptor circadian oscillator strongly relies on lighting conditions. Eur J Neurosci 2011; 34:507-16. [PMID: 21771113 DOI: 10.1111/j.1460-9568.2011.07772.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Mammalian retina harbours a self-sustained circadian clock able to synchronize to the light : dark (LD) cycle and to drive cyclic outputs such as night-time melatonin synthesis. Clock genes are expressed in distinct parts of the tissue, and it is presently assumed that the retina contains several circadian oscillators. However, molecular organization of cell type-specific clockworks has been poorly investigated. Here, we questioned the presence of a circadian clock in rat photoreceptors by studying 24-h kinetics of clock and clock output gene expression in whole photoreceptor layers isolated by vibratome sectioning. To address the importance of light stimulation towards photoreceptor clock properties, animals were exposed to 12 : 12 h LD cycle or 36 h constant darkness. Clock, Bmal1, Per1, Per2, Cry1, Cry2, RevErbα and Rorβ clock genes were all found to be expressed in photoreceptors and to display rhythmic transcription in LD cycle. Clock genes in whole retinas, used as a reference, also showed rhythmic expression with marked similarity to the profiles in pure photoreceptors. In contrast, clock gene oscillations were no longer detectable in photoreceptor layers after 36 h darkness, with the exception of Cry2 and Rorβ. Importantly, transcripts from two well-characterized clock output genes, Aanat (arylalkylamine N-acetyltransferase) and c-fos, retained sustained rhythmicity. We conclude that rat photoreceptors contain the core machinery of a circadian oscillator likely to be operative and to drive rhythmic outputs under exposure to a 24-h LD cycle. Constant darkness dramatically alters the photoreceptor clockwork and circadian functions might then rely on inputs from extra-photoreceptor oscillators.
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Affiliation(s)
- Cristina Sandu
- Département de Neurobiologie des Rythmes, CNRS UPR 3212 - Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
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Doonan F, O’Driscoll C, Kenna P, Cotter TG. Enhancing survival of photoreceptor cells in vivo using the synthetic progestin Norgestrel. J Neurochem 2011; 118:915-27. [DOI: 10.1111/j.1471-4159.2011.07354.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Transplantation of photoreceptor and total neural retina preserves cone function in P23H rhodopsin transgenic rat. PLoS One 2010; 5:e13469. [PMID: 20976047 PMCID: PMC2957406 DOI: 10.1371/journal.pone.0013469] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Accepted: 07/27/2010] [Indexed: 01/13/2023] Open
Abstract
Background Transplantation as a therapeutic strategy for inherited retinal degeneration has been historically viewed to restore vision as a method by replacing the lost retinal cells and attempting to reconstruct the neural circuitry with stem cells, progenitor cells and mature neural retinal cells. Methods and Findings We present evidence for an alternative strategy aimed at preventing the secondary loss of cones, the most crucial photoreceptors for vision, by transplanting normal photoreceptors cells into the eye of the P23H rat, a model of dominant retinitis pigmentosa. We carried out transplantation of photoreceptors or total neural retina in 3-month-old P23H rats and evaluated the function and cell counts 6 months after surgery. In both groups, cone loss was significantly reduced (10%) in the transplanted eyes where the cone outer segments were found to be considerably longer. This morphological effect correlated with maintenance of the visual function of cones as scored by photopic ERG recording, but more precisely with an increase in the photopic b-wave amplitudes by 100% and 78% for photoreceptor transplantation and whole retinal transplantation respectively. Conclusions We demonstrate here that the transplanted tissue prevents the loss of cone function, which is further translated into cone survival.
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Abstract
By its action on rhodopsin, light triggers the well-known visual transduction cascade, but can also induce cell damage and death through phototoxic mechanisms - a comprehensive understanding of which is still elusive despite more than 40 years of research. Herein, we integrate recent experimental findings to address several hypotheses of retinal light damage, premised in part on the close anatomical and metabolic relationships between the photoreceptors and the retinal pigment epithelium. We begin by reviewing the salient features of light damage, recently joined by evidence for retinal remodeling which has implications for the prognosis of recovery of function in retinal degenerations. We then consider select factors that influence the progression of the damage process and the extent of visual cell loss. Traditional, genetically modified, and emerging animal models are discussed, with particular emphasis on cone visual cells. Exogenous and endogenous retinal protective factors are explored, with implications for light damage mechanisms and some suggested avenues for future research. Synergies are known to exist between our long term light environment and photoreceptor cell death in retinal disease. Understanding the molecular mechanisms of light damage in a variety of animal models can provide valuable insights into the effects of light in clinical disorders and may form the basis of future therapies to prevent or delay visual cell loss.
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Reichman S, Kalathur RKR, Lambard S, Aït-Ali N, Yang Y, Lardenois A, Ripp R, Poch O, Zack DJ, Sahel JA, Léveillard T. The homeobox gene CHX10/VSX2 regulates RdCVF promoter activity in the inner retina. Hum Mol Genet 2009; 19:250-61. [PMID: 19843539 DOI: 10.1093/hmg/ddp484] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Rod-derived Cone Viability Factor (RdCVF) is a trophic factor with therapeutic potential for the treatment of retinitis pigmentosa, a retinal disease that commonly results in blindness. RdCVF is encoded by Nucleoredoxin-like 1 (Nxnl1), a gene homologous with the family of thioredoxins that participate in the defense against oxidative stress. RdCVF expression is lost after rod degeneration in the first phase of retinitis pigmentosa, and this loss has been implicated in the more clinically significant secondary cone degeneration that often occurs. Here, we describe a study of the Nxnl1 promoter using an approach that combines promoter and transcriptomic analysis. By transfection of selected candidate transcription factors, chosen based upon their expression pattern, we identified the homeodomain proteins CHX10/VSX2, VSX1 and PAX4, as well as the zinc finger protein SP3, as factors that can stimulate both the mouse and human Nxnl1 promoter. In addition, CHX10/VSX2 binds to the Nxnl1 promoter in vivo. Since CHX10/VSX2 is expressed predominantly in the inner retina, this finding motivated us to demonstrate that RdCVF is expressed in the inner as well as the outer retina. Interestingly, the loss of rods in the rd1 mouse, a model of retinitis pigmentosa, is associated with decreased expression of RdCVF by inner retinal cells as well as by rods. Based upon these results, we propose an alternative therapeutic strategy aimed at recapitulating RdCVF expression in the inner retina, where cell loss is not significant, to prevent secondary cone death and central vision loss in patients suffering from retinitis pigmentosa.
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Affiliation(s)
- Sacha Reichman
- Department of Genetics, Institut de la Vision, INSERM Université Pierre et Marie Curie-Paris 6, UMR-S 968, Paris, France
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Bringmann A, Iandiev I, Pannicke T, Wurm A, Hollborn M, Wiedemann P, Osborne NN, Reichenbach A. Cellular signaling and factors involved in Müller cell gliosis: neuroprotective and detrimental effects. Prog Retin Eye Res 2009; 28:423-51. [PMID: 19660572 DOI: 10.1016/j.preteyeres.2009.07.001] [Citation(s) in RCA: 506] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Müller cells are active players in normal retinal function and in virtually all forms of retinal injury and disease. Reactive Müller cells protect the tissue from further damage and preserve tissue function by the release of antioxidants and neurotrophic factors, and may contribute to retinal regeneration by the generation of neural progenitor/stem cells. However, Müller cell gliosis can also contribute to neurodegeneration and impedes regenerative processes in the retinal tissue by the formation of glial scars. This article provides an overview of the neuroprotective and detrimental effects of Müller cell gliosis, with accounts on the cellular signal transduction mechanisms and factors which are implicated in Müller cell-mediated neuroprotection, immunomodulation, regulation of Müller cell proliferation, upregulation of intermediate filaments, glial scar formation, and the generation of neural progenitor/stem cells. A proper understanding of the signaling mechanisms implicated in gliotic alterations of Müller cells is essential for the development of efficient therapeutic strategies that increase the supportive/protective and decrease the destructive roles of gliosis.
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Affiliation(s)
- Andreas Bringmann
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Liebigstrasse 10-14, D-04103 Leipzig, Germany.
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Frohns F, Mager M, Layer PG. Basic fibroblast growth factor increases the precursor pool of photoreceptors, but inhibits their differentiation and apoptosis in chicken retinal reaggregates. Eur J Neurosci 2009; 29:1931-42. [PMID: 19453639 DOI: 10.1111/j.1460-9568.2009.06738.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The role(s) of basic fibroblast growth factor (bFGF, FGF-2) in the differentiation and survival of photoreceptor (PR) cells was investigated in three-dimensional reaggregated histotypic spheres, derived from dispersed cells of the embryonic day 6 chicken embryo retina. Novel data processing methods are introduced to reliably quantify sphere sizes and spatial distributions of immunochemical signals in spheroids. Supplementation with 25 ng/mL FGF-2 increased cell proliferation, detected by bromodeoxyuridine uptake, and growth of spheroids. Immunochemical studies showed that FGF-2 decreased the number of visinin-positive and XAP-1-positive cells, including the total PR pool from early precursor until mature states, whereas the number of Pax6-positive amacrine cells was strongly increased. Notably, the relative number of PR precursors as detected by an Islet2 antibody was increased. The further differentiation of both red/green cones and then rods, as detected by CERN-906 and CERN-901 antibody binding, was much delayed. In contrast, blocking system-inherent FGF-2 by suramin showed opposite effects. Addition of both FGF-2 plus suramin resulted in nearly normal levels of PR differentiation. Terminal deoxynucleotidyl transferase dUTP nick end labelling histochemistry showed that PR apoptosis, which generally progresses with the age of spheres, was strongly increased by suramin treatment. These results suggest that in a three-dimensional retinal tissue context, FGF-2 restricts the pool of PRs in favour of cells of the inner retina, increases and maintains their precursor pool, delays their differentiation, and also protects them from apoptosis.
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Affiliation(s)
- Florian Frohns
- Technische Universität Darmstadt, Entwicklungsbiologie & Neurogenetik, Schnittspahnstrasse 13, D-64287 Darmstadt, Germany
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Catalani E, Tomassini S, Dal Monte M, Bosco L, Casini G. Localization patterns of fibroblast growth factor 1 and its receptors FGFR1 and FGFR2 in postnatal mouse retina. Cell Tissue Res 2009; 336:423-38. [DOI: 10.1007/s00441-009-0787-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Accepted: 02/23/2009] [Indexed: 11/29/2022]
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Lavail MM, Nishikawa S, Duncan JL, Yang H, Matthes MT, Yasumura D, Vollrath D, Overbeek PA, Ash JD, Robinson ML. Sustained delivery of NT-3 from lens fiber cells in transgenic mice reveals specificity of neuroprotection in retinal degenerations. J Comp Neurol 2009; 511:724-35. [PMID: 18925574 DOI: 10.1002/cne.21858] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Several neurotrophic factors (NTFs) are effective in protecting retinal photoreceptor cells from the damaging effects of constant light and slowing the rate of inherited photoreceptor degenerations. It is currently unclear whether, if continuously available, all NTFs can be protective for many or most retinal degenerations (RDs). We used transgenic mice that continuously overexpress the neurotrophin NT-3 from lens fibers under the control of the alphaA-crystallin promoter to test for neuroprotection in light-damage experiments and in four naturally occurring or transgenically induced RDs in mice. Lens-specific expression of NT-3 mRNA was demonstrated both by in situ hybridization in embryos and by reverse-transcriptase polymerase chain reaction (RT-PCR) in adult mice. Furthermore, NT-3 protein was found in abundance in the lens, ocular fluids, and retina by enzyme-linked immunosorbent assay (ELISA) and immunocytochemistry. Overexpression of NT-3 had no adverse effects on the structure or function of the retina for up to at least 14 months of age. Mice expressing the NT-3 transgene were protected from the damaging effects of constant light to a much greater degree than those receiving bolus injections of NT-3. When the NT-3 transgene was transferred into rd/rd, Rds/+, Q344ter mutant rhodopsin or Mertk knockout mice, overexpression of NT-3 had no protective effect on the RDs in these mice. Thus, specificity of the neuroprotective effect of NT-3 is clearly demonstrated, and different molecular mechanisms are inferred to mediate the protective effect in light-induced and inherited RDs.
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Affiliation(s)
- Matthew M Lavail
- Beckman Vision Center, University of California, San Francisco, San Francisco, California 94143-0730, USA
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36
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Zayas-Santiago A, Derwent JJK. Preservation of intact adult rat photoreceptors in vitro: study of dissociation techniques and the effect of light. Mol Vis 2009; 15:1-9. [PMID: 19137071 PMCID: PMC2614449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Accepted: 12/31/2008] [Indexed: 11/08/2022] Open
Abstract
PURPOSE Intact adult photoreceptors in culture can be a valuable tool in the search of therapies for retinal degenerations. The major challenge in this technique is that photoreceptors undergo an alteration in cytoarchitecture and loss of outer segment during the cell culture process. This study compared techniques for the isolation of photoreceptor cells from adult rat retinas to determine which technique yields the highest percent of structurally well preserved cells in vitro. In addition, the role of light exposure during the dissociation and culture process was investigated to minimize photoreceptor cell deformation over time in culture. METHODS Photoreceptor cells from adult rat retinas were isolated and quantified using three dissociation techniques: enzymatic dissociation with gentle pipeting; enzymatic dissociation with gentle pipeting and centrifugation; and non-enzymatic dissociation with gentle pipeting. To evaluate the effect of light exposure on cell deformation, we performed dissociations and cell seeding both in dark- and light-adapted conditions and measured the deformation of photoreceptors over a 12 h period right after dissociation. Cell viability in both conditions was evaluated after 4 and 7 days in culture. Preservation of cell structure in culture was assessed by immunofluorescence labeling of cells with anti-rhodopsin and 4',6-diamidino-2-phenylindole (DAPI) nuclear staining. RESULTS An enzymatic technique followed by gentle pipeting or mechanical trituration yielded the highest number of intact elongated photoreceptors right after dissociation. Data suggested that centrifugation after the dissociation contributed to cell deformation immediately after isolation. Immunohistochemistry results showed that cells had deformed into a circular shape by 2 days after seeding. However, photoreceptors isolated in dark conditions maintained their elongated shape, even 7 days after seeding. Performing experiments in dark also promoted a higher number of cells to remain viable with time. CONCLUSIONS The current study demonstrated the importance of proper isolation techniques to obtain the maximum amount of intact photoreceptor cells. The data suggested that a gentle dissociation technique, consisting of enzymatic treatment followed by moderate pipeting of the retinal tissue, may be the key to obtain a high number of intact or structurally preserved photoreceptors. Furthermore, isolation and cell culture procedures performed under dark conditions may facilitate to maintain high number of elongated photoreceptor cells in vitro.
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Saint-Geniez M, Maharaj ASR, Walshe TE, Tucker BA, Sekiyama E, Kurihara T, Darland DC, Young MJ, D'Amore PA. Endogenous VEGF is required for visual function: evidence for a survival role on müller cells and photoreceptors. PLoS One 2008; 3:e3554. [PMID: 18978936 PMCID: PMC2571983 DOI: 10.1371/journal.pone.0003554] [Citation(s) in RCA: 467] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Accepted: 10/09/2008] [Indexed: 01/03/2023] Open
Abstract
Background Vascular endothelial growth factor (VEGF) is well known for its role in normal and pathologic neovascularization. However, a growing body of evidence indicates that VEGF also acts on non-vascular cells, both developmentally as well as in the adult. In light of the widespread use of systemic and intraocular anti-VEGF therapies for the treatment of angiogenesis associated with tumor growth and wet macular degeneration, systematic investigation of the role of VEGF in the adult retina is critical. Methods and Findings Using immunohistochemistry and Lac-Z reporter mouse lines, we report that VEGF is produced by various cells in the adult mouse retina and that VEGFR2, the primary signaling receptor, is also widely expressed, with strong expression by Müller cells and photoreceptors. Systemic neutralization of VEGF was accomplished in mice by adenoviral expression of sFlt1. After 14 days of VEGF neutralization, there was no effect on the inner and outer retina vasculature, but a significant increase in apoptosis of cells in the inner and outer nuclear layers. By four weeks, the increase in neural cell death was associated with reduced thickness of the inner and outer nuclear layers and a decline in retinal function as measured by electroretinograms. siRNA-based suppression of VEGF expression in a Müller cell line in vitro supports the existence of an autocrine role for VEGF in Müller cell survival. Similarly, the addition of exogenous VEGF to freshly isolated photoreceptor cells and outer-nuclear-layer explants demonstrated VEGF to be highly neuroprotective. Conclusions These results indicate an important role for endogenous VEGF in the maintenance and function of adult retina neuronal cells and indicate that anti-VEGF therapies should be administered with caution.
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Affiliation(s)
- Magali Saint-Geniez
- Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Arindel S. R. Maharaj
- Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Tony E. Walshe
- Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Budd A. Tucker
- Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Eiichi Sekiyama
- Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Tomoki Kurihara
- Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Diane C. Darland
- University of North Dakota, Grand Forks, North Dakota, United States of America
| | - Michael J. Young
- Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Patricia A. D'Amore
- Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Pathology, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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Hertle D, Schleichert M, Steup A, Kirsch M, Hofmann HD. Regulation of cytokine signaling components in developing rat retina correlates with transient inhibition of rod differentiation by CNTF. Cell Tissue Res 2008; 334:7-16. [PMID: 18665395 DOI: 10.1007/s00441-008-0651-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2008] [Accepted: 05/20/2008] [Indexed: 10/21/2022]
Abstract
Ciliary neurotrophic factor (CNTF) is known to inhibit the differentiation of rod photoreceptors from postmitotic precursor cells. During early postnatal development, photoreceptor precursors lose their responsiveness to CNTF. The underlying events causing this change in responsiveness are unknown. Moreover, whether rods express CNTF receptor alpha, a prerequisite for a direct response to the factor, is controversial. Since morphological studies have previously produced conflicting results, we have analyzed the expression of cytokine receptor components and potential ligands in the rat photoreceptor layer by real-time reverse transcription with the polymerase chain reaction after laser microdissection and by immunoblotting. Cytokine effects on rods were studied in explant cultures from newborn rat retina. CNTF receptor alpha (CNTFR alpha) and leukemia inhibitory factor receptor ss (LIFRss) were expressed in immature photoreceptors. Expression of the CNTF-specific alpha-subunit (but not of LIFRss) was downregulated specifically in the photoreceptor layer in parallel with the appearance of opsin-positive rods. The decrease of CNTFR alpha levels in explant cultures was closely correlated with the loss of precursor cell responsiveness to CNTF. Increasing the CNTF concentration in the culture medium led to prolonged CNTFR alpha expression and, concomitantly, to persistent inhibition of rod differentiation. Application of CNTF and LIF in vitro induced phosphorylation of STAT3. Inducibility of STAT3 activation by CNTF decreased with photoreceptor maturation, whereas the LIF effect persisted. Our results thus indicate that CNTF acts directly on photoreceptor precursors inhibiting their differentiation via activation of the JAK/STAT3 signal transduction pathway, and that this effect is temporally limited because of the downregulation of CNTFR alpha.
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Affiliation(s)
- Daniel Hertle
- Institute of Anatomy and Cell Biology, University of Freiburg, P.O. Box 111, 79001, Freiburg, Germany
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Sheedlo HJ, Bartosh TJ, Wang Z, Srinivasan B, Brun-Zinkernagel AM, Roque RS. RPE-derived factors modulate photoreceptor differentiation: a possible role in the retinal stem cell niche. In Vitro Cell Dev Biol Anim 2007; 43:361-70. [PMID: 17924175 DOI: 10.1007/s11626-007-9051-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2007] [Accepted: 07/11/2007] [Indexed: 12/28/2022]
Abstract
A photoreceptor cell line, designated 661W, was tested for its response to growth factors secreted by retinal pigment epithelial cells including basic fibroblast growth factor, epidermal growth factor, and nerve growth factor. Early passaged 661W cells expressed high levels of retinal progenitor markers such as nestin and Pax6, but not opsin or glial fibrillary acidic protein. 661W cells grown in FGF-2 or EGF exhibited a multiple-process morphology with small phase-bright nuclei similar to neurons, whereas cells cultured in nerve growth factor (NGF) or retinal pigment epithelium (RPE)-conditioned medium (RPE-CM) displayed rounded profiles lacking processes. 661W cells grown in FGF-2 were slightly elevated, but not significantly above, control cultures; but cells treated with RPE-CM or NGF were fewer, approximately 63% and 49% of control, respectively. NGF immunodepletion of RPE-CM strongly suppressed the inhibitory activity of RPE-CM on cell proliferation. Cells treated with FGF-2, but not NGF, upregulated their expression of opsin. All treatment conditions resulted in almost 100% viability based on calcium AM staining. Cells grown on extracellular matrix proteins laminin, fibronectin, and/or collagen resembled those grown on untreated dishes. This study showed that early passaged 661W cells displayed characteristics of retinal progenitor cells. The 661W cells proliferated and appeared to mature morphologically expressing rod photoreceptor phenotype in response to FGF-2. In contrast, NGF and RPE-CM inhibited proliferation and morphological differentiation of 661W cells, possibly inducing cell cycle arrest. These findings are consistent with reports that the RPE modulates photoreceptor differentiation and retinal progenitor cells via secreted factors and may play a role in the regulation of the retinal stem cell niche.
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Affiliation(s)
- Harold J Sheedlo
- Department of Cell Biology and Genetics, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA.
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O'Driscoll C, Wallace D, Cotter TG. bFGF promotes photoreceptor cell survival in vitro by PKA-mediated inactivation of glycogen synthase kinase 3beta and CREB-dependent Bcl-2 up-regulation. J Neurochem 2007; 103:860-70. [PMID: 17714451 DOI: 10.1111/j.1471-4159.2007.04827.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Although there is substantial evidence supporting the neuroprotective efficacy of basic fibroblast growth factor (bFGF) in the rodent retina there is no consensus to date as to the protective mechanism involved. We hypothesise that bFGF can assert its neuroprotective effects directly on mouse photoreceptors transduced via the activation of specific intracellular signalling pathways. In mouse photoreceptor-derived 661W cells, bFGF promoted a rapid inactivation of glycogen synthase kinase 3beta (GSK3beta) by phosphorylation at Ser9. The effects of bFGF on GSK3beta were dependent on protein kinase A (PKA) activation, as inhibition of this pathway blocked inactivation. Furthermore, bFGF protection against oxidative stress was dependent on PKA inactivation of GSK3beta as PKA inhibition attenuated bFGF-induced protection. Furthermore, transfection of cells with mutant dominant negative GSK3betaS9A that cannot be phosphorylated on Ser9 also abrogated neuroprotection. Activation of the transcription factor cAMP-response element binding protein (CREB) and subsequent up-regulation of Bcl-2 in response to bFGF was also dependent on PKA as inhibition with H-89 attenuated increased pCREB levels and Bcl-2 expression. These results indicate that the protective efficacy of bFGF in mouse photoreceptors involves PKA-dependent inactivation of GSK3beta and subsequent up-regulation of Bcl-2 via CREB activation.
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Affiliation(s)
- Carolyn O'Driscoll
- Cell Development and Disease Laboratory, Biochemistry Department, Bioscience Research Institute, University College Cork, Cork, Ireland
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Abstract
Despite a relatively long history, general knowledge is not widespread that adult neurons can be maintained in cell culture for fairly extended periods of time. Within the central nervous system, this capacity seems to be particularly well developed in the retina, although it is still not clear whether this property is due to physical reasons (spatial configuration, simple connections) or to more fundamental differences (molecular composition, physiological function). Irrespective of the reasons, in vitro model systems are useful for investigating physiological and pathological processes occurring in mature retina. The authors argue that the numerous molecular changes undergone during maturation (modifications in ion channels and receptors, apoptotic pathways and growth factor effects) should be taken into account when using in vitro approaches to study processes involved in photoreceptor and ganglion cell degeneration, and hence that more classical methods relying on embryonic or newborn tissue should be interpreted with caution. A number of examples are given where the use of adult retinal neuronal culture may be especially informative: neurite regeneration, neuroprotection assays and pathogenic mechanisms; and areas of further research that should be explored: cell transplantation.
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Affiliation(s)
- Carl Romano
- Retina Discovery, Alcon Laboratories Inc., 6201 South Freeway, Fort Worth, TX 76134-2099, USA
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Araki M, Suzuki H, Layer P. Differential enhancement of neural and photoreceptor cell differentiation of cultured pineal cells by FGF-1, IGF-1, and EGF. Dev Neurobiol 2007; 67:1641-54. [PMID: 17577207 DOI: 10.1002/dneu.20534] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
There are several common features between the pineal organ and the lateral eye in their developmental and evolutionary aspects. The avian pineal is a photoendocrine organ that originates from the diencephalon roof and represents a transitional type between the photosensory organ of lower vertebrates and the endocrine gland of mammals. Previous cell culture studies have shown that embryonic avian pineal cells retain a wide spectrum of differentiative capacities, although little is known about the mechanisms involved in their fate determination. In the present study, we investigated the effects of various cell growth factors on the differentiation of photoreceptor and neural cell types using pineal cell cultures from quail embryos. The results show that IGF-1 promotes differentiation of rhodopsin-immunoreactive cells, but had no effect on neural cell differentiation. Simultaneous administration of EGF and IGF-1 further enhanced differentiation of rhodopsin-immunoreactive cells, although the mechanism of the synergistic effect is unknown. FGF-1 did not stimulate proliferation of neural progenitor cells, but intensively promoted and maintained expression of a neural cell phenotype. FGF-1 appeared to lead to the conversion from an epithelial (endocrinal) to a neuronal type. It also enhanced phenotypic expression of retinal ganglion cell markers but rather suppressed expression of an amacrine cell marker. These results indicate that growth factors are important regulatory cues for pineal cell differentiation and suggest that they play roles in determining the fate of the pineal organ and the eye. It can be speculated that the differences in environmental cues between the retina and pineal may result in the transition of the pineal primordium from a potentially ocular (retinal) organ to a photoendocrine organ.
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Affiliation(s)
- Masasuke Araki
- Developmental Neurobiology Laboratory, Department of Biological Sciences, Nara Women's University, Nara 630-8506, Japan.
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German OL, Insua MF, Gentili C, Rotstein NP, Politi LE. Docosahexaenoic acid prevents apoptosis of retina photoreceptors by activating the ERK/MAPK pathway. J Neurochem 2006; 98:1507-20. [PMID: 16923163 DOI: 10.1111/j.1471-4159.2006.04061.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Identifying the trophic factors for retina photoreceptors and the intracellular pathways activated to promote cell survival is crucial for treating retina neurodegenerative diseases. Docosahexaenoic acid (DHA), the major retinal polyunsaturated fatty acid, prevents photoreceptor apoptosis during early development in vitro, and upon oxidative stress. However, the signaling mechanisms activated by DHA are still unclear. We investigated whether the extracellular signal regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) or the phosphatidylinositol-3-kinase (PI3K) pathway participated in DHA protection. 1,4-Diamino-2,3-dicyano-1,4-bis(2-aminophynyltio) butadiene (U0126), a specific MEK inhibitor, completely blocked the DHA anti-apoptotic effect. DHA rapidly increased ERK phosphorylation in photoreceptors, whereas U0126 blocked this increase. U0126 hindered DHA prevention of mitochondrial depolarization, and blocked the DHA-induced increase in opsin expression. On the contrary, PI3K inhibitors did not diminish the DHA protective effect. DHA promoted the early expression of Bcl-2, decreased Bax expression and reduced caspase-3 activation in photoreceptors. These results suggest that DHA exclusively activates the ERK/MAPK pathway to promote photoreceptor survival during early development in vitro and upon oxidative stress. This leads to the regulation of Bcl-2 and Bax expression, thus preserving mitochondrial membrane potential and inhibiting caspase activation. Hence, DHA, a lipid trophic factor, promotes photoreceptor survival and differentiation by activating the same signaling pathways triggered by peptidic trophic factors.
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Affiliation(s)
- Olga Lorena German
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Universidad Nacional del Sur-CONICET, Buenos Aires, Argentina
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Hauck SM, Kinkl N, Deeg CA, Swiatek-de Lange M, Schöffmann S, Ueffing M. GDNF family ligands trigger indirect neuroprotective signaling in retinal glial cells. Mol Cell Biol 2006; 26:2746-57. [PMID: 16537917 PMCID: PMC1430306 DOI: 10.1128/mcb.26.7.2746-2757.2006] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2005] [Revised: 10/17/2005] [Accepted: 01/11/2006] [Indexed: 11/20/2022] Open
Abstract
Apoptotic cell death of photoreceptors is the final event leading to blindness in the heterogeneous group of inherited retinal degenerations. GDNF (glial cell-line-derived neurotrophic factor) was found to rescue photoreceptor function and survival very effectively in an animal model of retinal degeneration (M. Frasson, S. Picaud, T. Leveillard, M. Simonutti, S. Mohand-Said, H. Dreyfus, D. Hicks, and J. Sahel, Investig. Ophthalmol. Vis. Sci. 40:2724-2734, 1999). However, the cellular mechanism of GDNF action remained unresolved. We show here that in porcine retina, GDNF receptors GFRalpha-1 and RET are expressed on retinal Mueller glial cells (RMG) but not on photoreceptors. Additionally, RMG express the receptors for the GDNF family members artemin and neurturin (GFRalpha-2 and GFRalpha-3). We further investigated GDNF-, artemin-, and neurturin-induced signaling in isolated primary RMG and demonstrate three intracellular cascades, which are activated in vitro: MEK/ERK, stress-activated protein kinase (SAPK), and PKB/AKT pathways with different kinetics in dependence on stimulating GFL. We correlate the findings to intact porcine retina, where GDNF induces phosphorylation of ERK in the perinuclear region of RMG located in the inner nuclear layer. GDNF signaling resulted in transcriptional upregulation of FGF-2, which in turn was found to support photoreceptor survival in an in vitro assay. We provide here a detailed model of GDNF-induced signaling in mammalian retina and propose that the GDNF-induced rescue effect on mutated photoreceptors is an indirect effect mediated by retinal Mueller glial cells.
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Affiliation(s)
- Stefanie M Hauck
- GSF-National Research Center for Environment and Health, Institute of Human Genetics, Ingolstaedter Landstrasse 1, 85764 Munich-Neuherberg, Germany
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Abstract
Progress in the study of the molecular mechanisms that regulate neuronal differentiation has been quite impressive in recent years, and promises to continue to an equally fast pace. This should not lead us into a sense of complacency, however, because there are still significant barriers that cannot be overcome by simply conducting the same type of experiments that we have been performing thus far. This article will describe some of these challenges, while highlighting the conceptual and methodological breakthroughs that will be necessary to overcome them.
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Affiliation(s)
- Ruben Adler
- Department of Ophthalmology and Neuroscience The Johns Hopkins University School of Medicine Baltimore, MD 21287-9257, USA.
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Gómez-Vicente V, Donovan M, Cotter TG. Multiple death pathways in retina-derived 661W cells following growth factor deprivation: crosstalk between caspases and calpains. Cell Death Differ 2005; 12:796-804. [PMID: 15846377 DOI: 10.1038/sj.cdd.4401621] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
During development of the mammalian retina, neurons that do not succeed in establishing functional synaptic connections are eliminated by apoptosis, allowing the formation of a finely tuned network. Growth factors play a crucial role in controlling the balance between apoptosis and survival signals not only at developmental stages but also in long-term preservation of retinal functions. In the present work, we explore the apoptotic mechanisms triggered by growth factor deprivation of retina-derived 661W cells. Under serum starvation conditions, these cone photoreceptors underwent cell death with participation of caspase-9, -3 and -12. Interestingly, inhibition of caspases did not prevent apoptosis but only resulted in a temporary delay. We show m-calpain activation in parallel with caspases, indicating that more than one execution pathway is available to cone photoreceptors. Moreover, crosstalk of the caspase and calpain pathways was detected, suggesting a loop that may act to amplify the apoptotic cascade.
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Affiliation(s)
- V Gómez-Vicente
- Cell Development and Disease Laboratory, Department of Biochemistry, Biosciences Research Institute, University College Cork, Cork, Ireland
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47
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Cinaroglu A, Ozmen Y, Ozdemir A, Ozcan F, Ergorul C, Cayirlioglu P, Hicks D, Bugra K. Expression and possible function of fibroblast growth factor 9 (FGF9) and its cognate receptors FGFR2 and FGFR3 in postnatal and adult retina. J Neurosci Res 2005; 79:329-39. [PMID: 15614790 DOI: 10.1002/jnr.20363] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Fibroblast growth factors (FGFs) are important regulators of retinal development and survival. We examined the expression and distribution of FGF9 and its preferred receptors FGFR2IIIc and FGFR3IIIc in this tissue. FGF9 transcripts in whole rat retina were detected by RT-PCR but were not present in purified cultured Muller glia. Transcripts appeared as 3.2-kb and 4.0-kb bands on Northern blots, and Western blotting of whole retina revealed FGF9-immunoreactive bands at 30 and 55 kDa. FGF9 mRNA demonstrated a biphasic expression profile, elevated at birth and adulthood, but relatively decreased during terminal retinal differentiation (4-14 days postnatal). Antibody labeling broadly reflected these findings: staining in vivo was observed mainly in the inner retina (and outer plexiform layer in adults) whereas FGF9 was not detectable in cultured Muller glia. In adults, FGF9 in situ hybridization also showed a detectable signal in inner retina. FGFR2IIIc and FGFR3IIIc were detected by RT-PCR, and Western blotting showed both FGFRs existed as multiple forms between approximately 100-200 kDa. FGFR2 and FGFR3 antibodies showed prominent labeling in the inner retina, especially in proliferating cultured Muller glia. Exogenous FGF9 elicited a dose-dependent increase in Muller glial proliferation in vitro. These data suggest a role for FGF9 in retinal differentiation and maturation, possibly representing a neuronally derived factor acting upon glial (and other) cells.
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MESH Headings
- Aging/metabolism
- Animals
- Animals, Newborn
- Cell Differentiation/drug effects
- Cell Differentiation/physiology
- Cell Proliferation/drug effects
- Dose-Response Relationship, Drug
- Fibroblast Growth Factor 9
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/metabolism
- Fibroblast Growth Factors/pharmacology
- Gene Expression Regulation, Developmental/drug effects
- Gene Expression Regulation, Developmental/physiology
- Neuroglia/drug effects
- Neuroglia/metabolism
- Neurons/metabolism
- Protein Isoforms/metabolism
- Protein-Tyrosine Kinases/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Wistar
- Receptor Protein-Tyrosine Kinases/metabolism
- Receptor, Fibroblast Growth Factor, Type 2
- Receptor, Fibroblast Growth Factor, Type 3
- Receptors, Fibroblast Growth Factor/metabolism
- Retina/growth & development
- Retina/metabolism
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Affiliation(s)
- Ayca Cinaroglu
- Department of Molecular Biology and Genetics, Bogazici University, Istanbul, Turkey
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Léveillard T, Mohand-Saïd S, Lorentz O, Hicks D, Fintz AC, Clérin E, Simonutti M, Forster V, Cavusoglu N, Chalmel F, Dollé P, Poch O, Lambrou G, Sahel JA. Identification and characterization of rod-derived cone viability factor. Nat Genet 2004; 36:755-9. [PMID: 15220920 DOI: 10.1038/ng1386] [Citation(s) in RCA: 297] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2003] [Accepted: 05/17/2004] [Indexed: 11/09/2022]
Abstract
Retinitis pigmentosa is an untreatable, inherited retinal disease that leads to blindness. The disease initiates with the loss of night vision due to rod photoreceptor degeneration, followed by irreversible, progressive loss of cone photoreceptor. Cone loss is responsible for the main visual handicap, as cones are essential for day and high-acuity vision. Their loss is indirect, as most genes associated with retinitis pigmentosa are not expressed by these cells. We previously showed that factors secreted from rods are essential for cone viability. Here we identified one such trophic factor by expression cloning and named it rod-derived cone viability factor (RdCVF). RdCVF is a truncated thioredoxin-like protein specifically expressed by photoreceptors. The identification of this protein offers new treatment possibilities for retinitis pigmentosa.
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Affiliation(s)
- Thierry Léveillard
- Laboratoire de Physiopathologie Cellulaire et Moléculaire et de la Rétine, Inserm U592, Université Pierre et Marie Curie, Hôpital St-Antoine, 184 rue du Faubourg St-Antoine, 75571, Paris cedex 12, France
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Bonnet D, Garcia M, Vecino E, Lorentz JG, Sahel J, Hicks D. Brain-derived neurotrophic factor signalling in adult pig retinal ganglion cell neurite regeneration in vitro. Brain Res 2004; 1007:142-51. [PMID: 15064145 DOI: 10.1016/j.brainres.2004.02.023] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/11/2004] [Indexed: 11/26/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) has been implicated in stimulating retinal ganglion cell (RGC) survival and axonal regeneration in rodent animal models in vivo and in vitro, but very little data are available on neurotrophin effects in higher mammals. We hence analysed BDNF signalling in primary cultures of adult pig RGC. As detected by immunohistochemistry, HPLC analysis and RT-PCR, BDNF protein and mRNA were present within pig retina in vivo and in vitro, where it may be involved in baseline RGC neuritogenesis. Initial dose-response studies established optimal effects were induced by 20 ng/ml BDNF, leading to an approximately threefold increase in neurite length. We analysed the respective contributions of phosphatidyl inositol 3 kinase (PI3K) and mitogen activated protein kinase (MAPK) cascades to BDNF-induced neurite regeneration. Addition of either the PI3K inhibitor wortmannin or the MAPK inhibitor U0126 blocked 50-100% BDNF-induced neurite elongation; U0126 also significantly reduced neurite regeneration below untreated control levels. The trk receptor inhibitor K252a had no observable effect on neurite regeneration or morphology. These data hence demonstrate that BDNF is a potent stimulator of neurite growth in RGC prepared from an adult large mammal retina, and that at least two signalling pathways are causally involved. BDNF-based therapy may be of potential use in treating RGC degeneration in humans.
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Affiliation(s)
- Delphine Bonnet
- Laboratoire de Physiopathologie Cellulaire et Moléculaire de la Rétine, INSERM U. 592, Clinique Médicale A, Centre Hospitalier Universitaire, BP 426, 67091 Strasbourg, France
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50
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Takano Y, Ohguro H, Dezawa M, Ishikawa H, Yamazaki H, Ohguro I, Mamiya K, Metoki T, Ishikawa F, Nakazawa M. Study of drug effects of calcium channel blockers on retinal degeneration of rd mouse. Biochem Biophys Res Commun 2004; 313:1015-22. [PMID: 14706644 DOI: 10.1016/j.bbrc.2003.12.034] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the present study, we studied drug effects of Ca(2+) antagonists on the retinal degeneration of rd mouse to evaluate their efficacy. Several kinds of Ca(2+) antagonists, diltiazem, nicardipine, nilvadipine or nifedipine were administrated intraperitoneally and thereafter retinal morphology and functions were analyzed. In addition, we performed DNA microarray analysis both in nilvadipine treated and control retinas to understand their drug effects at molecular levels. We found that nilvadipine caused significant preservation of retinal thickness in rd mouse during the initial stage of the retinal degeneration, and nicardipine showed also significant but lesser preservation than nilvadipine. However, we recognized no preservation effects of diltiazem and nifedipine. In the total 3774 genes, the expressions of 27 genes were altered upon administration of nilvadipine, including several genes related to the apoptotic pathway, neuro-survival factor, Ca(2+) metabolisms, and other mechanisms. It is suggested that some types of Ca(2+) channel blockers, such as nilvadipine and nicardipine, are able to preserve photoreceptor cells in rd mouse and can potentially be used to treat some RP patients.
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Affiliation(s)
- Yoshiko Takano
- Department of Ophthalmology, Hirosaki University School of Medicine, Japan
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