1
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Bora K, Kushwah N, Maurya M, Pavlovich MC, Wang Z, Chen J. Assessment of Inner Blood-Retinal Barrier: Animal Models and Methods. Cells 2023; 12:2443. [PMID: 37887287 PMCID: PMC10605292 DOI: 10.3390/cells12202443] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 10/07/2023] [Accepted: 10/08/2023] [Indexed: 10/28/2023] Open
Abstract
Proper functioning of the neural retina relies on the unique retinal environment regulated by the blood-retinal barrier (BRB), which restricts the passage of solutes, fluids, and toxic substances. BRB impairment occurs in many retinal vascular diseases and the breakdown of BRB significantly contributes to disease pathology. Understanding the different molecular constituents and signaling pathways involved in BRB development and maintenance is therefore crucial in developing treatment modalities. This review summarizes the major molecular signaling pathways involved in inner BRB (iBRB) formation and maintenance, and representative animal models of eye diseases with retinal vascular leakage. Studies on Wnt/β-catenin signaling are highlighted, which is critical for retinal and brain vascular angiogenesis and barriergenesis. Moreover, multiple in vivo and in vitro methods for the detection and analysis of vascular leakage are described, along with their advantages and limitations. These pre-clinical animal models and methods for assessing iBRB provide valuable experimental tools in delineating the molecular mechanisms of retinal vascular diseases and evaluating therapeutic drugs.
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Affiliation(s)
| | | | | | | | | | - Jing Chen
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
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2
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Herat LY, Matthews JR, Hibbs M, Rakoczy EP, Schlaich MP, Matthews VB. SGLT1/2 inhibition improves glycemic control and multi-organ protection in type 1 diabetes. iScience 2023; 26:107260. [PMID: 37520739 PMCID: PMC10384225 DOI: 10.1016/j.isci.2023.107260] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 04/26/2023] [Accepted: 06/27/2023] [Indexed: 08/01/2023] Open
Abstract
Sodium glucose cotransporters (SGLTs) are transport proteins that are expressed throughout the body. Inhibition of SGLTs is a relatively novel therapeutic strategy to improve glycemic control and has been shown to promote cardiorenal benefits. Dual SGLT1/2 inhibitors (SGLT1/2i) such as sotagliflozin target both SGLT1 and 2 proteins. Sotagliflozin or vehicle was administered to diabetic Akimba mice for 8 weeks at a dose of 25 mg/kg/day. Urine glucose levels, water consumption, and body weight were measured weekly. Serum, kidney, pancreas, and brain tissue were harvested under terminal anesthesia. Tissues were assessed using immunohistochemistry or ELISA techniques. Treatment with sotagliflozin promoted multiple metabolic benefits in diabetic Akimba mice resulting in decreased blood glucose and improved polydipsia. Sotagliflozin also prevented mortalities associated with diabetes. Our data suggests that there is the possibility that combined SGLT1/2i may be superior to SGLT2i in controlling glucose homeostasis and provides protection of multiple organs affected by diabetes.
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Affiliation(s)
- Lakshini Yasaswi Herat
- Dobney Hypertension Centre, School of Biomedical Sciences – Royal Perth Hospital Unit / Royal Perth Hospital Medical Research Foundation, University of Western Australia, Crawley, WA 6009, Australia
| | - Jennifer Rose Matthews
- Dobney Hypertension Centre, School of Biomedical Sciences – Royal Perth Hospital Unit / Royal Perth Hospital Medical Research Foundation, University of Western Australia, Crawley, WA 6009, Australia
| | - Moira Hibbs
- Research Centre, Royal Perth Hospital, Perth, WA 6000, Australia
| | | | - Markus Peter Schlaich
- Dobney Hypertension Centre, Medical School – Royal Perth Hospital Unit / Royal Perth Hospital Medical Research Foundation, University of Western Australia, Crawley, WA 6009, Australia
- Department of Cardiology and Department of Nephrology, Royal Perth Hospital, Perth, WA 6000, Australia
| | - Vance Bruce Matthews
- Dobney Hypertension Centre, School of Biomedical Sciences – Royal Perth Hospital Unit / Royal Perth Hospital Medical Research Foundation, University of Western Australia, Crawley, WA 6009, Australia
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3
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Yamaguchi M, Nakao S, Wada I, Matoba T, Arima M, Kaizu Y, Shirane M, Ishikawa K, Nakama T, Murakami Y, Mizuochi M, Shiraishi W, Yamasaki R, Hisatomi T, Ishibashi T, Shibuya M, Stitt AW, Sonoda KH. Identifying Hyperreflective Foci in Diabetic Retinopathy via VEGF-Induced Local Self-Renewal of CX3CR1+ Vitreous Resident Macrophages. Diabetes 2022; 71:2685-2701. [PMID: 36203331 DOI: 10.2337/db21-0247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 09/13/2022] [Indexed: 01/11/2023]
Abstract
Intraretinal hyperreflective foci (HRF) are significant biomarkers for diabetic macular edema. However, HRF at the vitreoretinal interface (VRI) have not been examined in diabetic retinopathy (DR). A prospective observational clinical study with 162 consecutive eyes using OCT imaging showed significantly increased HRF at the VRI during DR progression (P < 0.01), which was reversed by anti-vascular endothelial growth factor (VEGF) therapy. F4/80+ macrophages increased significantly at the VRI in Kimba (vegfa+/+) or Akimba (Akita × Kimba) mice (both P < 0.01), but not in diabetic Akita (Ins2+/-) mice, indicating macrophage activation was modulated by elevated VEGF rather than the diabetic milieu. Macrophage depletion significantly reduced HRF at the VRI (P < 0.01). Furthermore, BrdU administration in Ccr2rfp/+Cx3cr1gfp/+vegfa+/- mice identified a significant contribution of M2-like tissue-resident macrophages (TRMs) at the VRI. Ki-67+ and CD11b+ cells were observed in preretinal tissues of DR patients, while exposure of vitreal macrophages to vitreous derived from PDR patients induced a significant proliferation response in vitro (P < 0.01). Taken together, the evidence suggests that VEGF drives a local proliferation of vitreous resident macrophages (VRMs) at the VRI during DR. This phenomenon helps to explain the derivation and disease-relevance of the HRF lesions observed through OCT imaging in patients.
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Affiliation(s)
- Muneo Yamaguchi
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Shintaro Nakao
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
- Department of Ophthalmology, National Hospital Organization, Kyushu Medical Center, Fukuoka, Japan
- Clinical Research Institute, National Hospital Organization, Kyushu Medical Center, Fukuoka, Japan
| | - Iori Wada
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Tetsuya Matoba
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Mitsuru Arima
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yoshihiro Kaizu
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Mariko Shirane
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Keijiro Ishikawa
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Takahito Nakama
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yusuke Murakami
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | | | - Wataru Shiraishi
- Department of Neurology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Ryo Yamasaki
- Department of Neurology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Toshio Hisatomi
- Department of Ophthalmology, Fukuoka University Chikushi Hospital, Fukuoka, Japan
| | - Tatsuro Ishibashi
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Masabumi Shibuya
- Institute of Physiology and Medicine, Jobu University, Gunma, Japan
| | - Alan W Stitt
- Wellcome Wolfson Institute for Experimental Medicine, Queen's University, Belfast, Northern Ireland
| | - Koh-Hei Sonoda
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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4
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Becker K, Weigelt CM, Fuchs H, Viollet C, Rust W, Wyatt H, Huber J, Lamla T, Fernandez-Albert F, Simon E, Zippel N, Bakker RA, Klein H, Redemann NH. Transcriptome analysis of AAV-induced retinopathy models expressing human VEGF, TNF-α, and IL-6 in murine eyes. Sci Rep 2022; 12:19395. [PMID: 36371417 PMCID: PMC9653384 DOI: 10.1038/s41598-022-23065-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 10/25/2022] [Indexed: 11/14/2022] Open
Abstract
Retinopathies are multifactorial diseases with complex pathologies that eventually lead to vision loss. Animal models facilitate the understanding of the pathophysiology and identification of novel treatment options. However, each animal model reflects only specific disease aspects and understanding of the specific molecular changes in most disease models is limited. Here, we conducted transcriptome analysis of murine ocular tissue transduced with recombinant Adeno-associated viruses (AAVs) expressing either human VEGF-A, TNF-α, or IL-6. VEGF expression led to a distinct regulation of extracellular matrix (ECM)-associated genes. In contrast, both TNF-α and IL-6 led to more comparable gene expression changes in interleukin signaling, and the complement cascade, with TNF-α-induced changes being more pronounced. Furthermore, integration of single cell RNA-Sequencing data suggested an increase of endothelial cell-specific marker genes by VEGF, while TNF-α expression increased the expression T-cell markers. Both TNF-α and IL-6 expression led to an increase in macrophage markers. Finally, transcriptomic changes in AAV-VEGF treated mice largely overlapped with gene expression changes observed in the oxygen-induced retinopathy model, especially regarding ECM components and endothelial cell-specific gene expression. Altogether, our study represents a valuable investigation of gene expression changes induced by VEGF, TNF-α, and IL-6 and will aid researchers in selecting appropriate animal models for retinopathies based on their agreement with the human pathophysiology.
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Affiliation(s)
- Kolja Becker
- grid.420061.10000 0001 2171 7500Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Carina M. Weigelt
- grid.420061.10000 0001 2171 7500Cardiometabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Holger Fuchs
- grid.420061.10000 0001 2171 7500Cardiometabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Coralie Viollet
- grid.420061.10000 0001 2171 7500Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Werner Rust
- grid.420061.10000 0001 2171 7500Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Hannah Wyatt
- grid.420061.10000 0001 2171 7500Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Jochen Huber
- grid.420061.10000 0001 2171 7500Clinical Development & Operations Corporate, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Thorsten Lamla
- grid.420061.10000 0001 2171 7500Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Francesc Fernandez-Albert
- grid.420061.10000 0001 2171 7500Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Eric Simon
- grid.420061.10000 0001 2171 7500Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Nina Zippel
- grid.420061.10000 0001 2171 7500Cardiometabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Remko A. Bakker
- grid.420061.10000 0001 2171 7500Cardiometabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Holger Klein
- grid.420061.10000 0001 2171 7500Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Norbert H. Redemann
- grid.420061.10000 0001 2171 7500Cardiometabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
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5
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Determining the role of SGLT2 inhibition with Empagliflozin in the development of diabetic retinopathy. Biosci Rep 2022; 42:230970. [PMID: 35234250 PMCID: PMC8891593 DOI: 10.1042/bsr20212209] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 02/11/2022] [Accepted: 02/16/2022] [Indexed: 12/11/2022] Open
Abstract
Diabetes mellitus is a chronic metabolic disease that occurs when the pancreas is not producing enough insulin or when the insulin that it does produce is not able to be used effectively in the body. This results in hyperglycemia and if the blood sugars are not controlled, then it can lead to serious damage of various body systems, especially the nerves and the blood vessels. Uncontrolled diabetes is a major cause of kidney failure, heart attacks, stroke and amputation. One of the most devastating complications for patients is diabetic retinopathy (DR) which represents the leading cause of preventable vision loss in people between 20 and 65 years of age. Sodium glucose transporter 2 (SGLT2) inhibitors have been shown to reduce the risk for cardiovascular and renal events, however literature highlighting their potential role to prevent DR is limited. We therefore used a relevant mouse model (Akimba) to explore the effects of the SGLT2 inhibitor, Empagliflozin (EMPA), on the development of diabetic retinal changes. Here we show that when given in the early stages of type 1 diabetes (T1D), EMPA reduced the weight loss usually associated with T1D, decreased diabetes-associated polydipsia, lowered fasting blood glucose levels, decreased kidney-to-body weight ratios and, most importantly in the current context, substantially reduced retinal abnormalities associated with DR. We show that EMPA reduces vascular leakage indicated by lower albumin staining in the vitreous humor and diminishes expression of the pathogenic factor VEGF in the retina. Additionally, EMPA significantly alters the retinal genetic signature. Our findings suggest that SGLT2 inhibition may be a useful therapeutic approach to prevent the development of DR and its severity if given early in the disease process.
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6
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Matthews JR, Schlaich MP, Rakoczy EP, Matthews VB, Herat LY. The Effect of SGLT2 Inhibition on Diabetic Kidney Disease in a Model of Diabetic Retinopathy. Biomedicines 2022; 10:biomedicines10030522. [PMID: 35327323 PMCID: PMC8944990 DOI: 10.3390/biomedicines10030522] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 02/18/2022] [Accepted: 02/18/2022] [Indexed: 02/04/2023] Open
Abstract
Diabetic kidney disease (DKD) is a chronic disorder characterized by elevated urine albumin excretion, reduced glomerular filtration rate, or both. At present, angiotensin-converting enzyme inhibitors or angiotensin receptor blockers are the standard care for the treatment of DKD, resulting in improved outcomes. However, alternative treatments may be required because although the standard treatments have been found to slow the progression of DKD, they have not been found to halt the disease. In the past decade, sodium glucose co-transporter 2 (SGLT2) inhibitors have been widely researched in the area of cardiovascular disease and diabetes and have been shown to improve cardiovascular outcomes. SGLT2 inhibitors including canagliflozin and dapagliflozin have been shown to slow the progression of kidney disease. There is currently an omission of literature where three SGLT2 inhibitors have been simultaneously compared in a rodent diabetic model. After diabetic Akimba mice were treated with SGLT2 inhibitors for 8 weeks, there was not only a beneficial impact on the pancreas, signified by an increase in the islet mass and increased plasma insulin levels, but also on the kidneys, signified by a reduction in average kidney to body weight ratio and improvement in renal histology. These findings suggest that SGLT2 inhibition promotes improvement in both pancreatic and kidney health.
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Affiliation(s)
- Jennifer Rose Matthews
- Dobney Hypertension Centre, School of Biomedical Sciences—Royal Perth Hospital Unit, University of Western Australia, Crawley, WA 6009, Australia; (J.R.M.); (V.B.M.)
| | - Markus P. Schlaich
- Dobney Hypertension Centre, Medical School—Royal Perth Hospital Unit, University of Western Australia, Crawley, WA 6009, Australia;
- Department of Cardiology and Department of Nephrology, Royal Perth Hospital, Perth, WA 6000, Australia
| | - Elizabeth Piroska Rakoczy
- Department of Molecular Ophthalmology, University of Western Australia, Crawley, WA 6009, Australia;
| | - Vance Bruce Matthews
- Dobney Hypertension Centre, School of Biomedical Sciences—Royal Perth Hospital Unit, University of Western Australia, Crawley, WA 6009, Australia; (J.R.M.); (V.B.M.)
| | - Lakshini Yasaswi Herat
- Dobney Hypertension Centre, School of Biomedical Sciences—Royal Perth Hospital Unit, University of Western Australia, Crawley, WA 6009, Australia; (J.R.M.); (V.B.M.)
- Correspondence: ; Tel.: +61-8-9224-0239
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7
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Animal models of diabetic microvascular complications: Relevance to clinical features. Biomed Pharmacother 2021; 145:112305. [PMID: 34872802 DOI: 10.1016/j.biopha.2021.112305] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 09/29/2021] [Accepted: 10/05/2021] [Indexed: 02/06/2023] Open
Abstract
Diabetes has become more common in recent years worldwide, and this growth is projected to continue in the future. The primary concern with diabetes is developing various complications, which significantly contribute to the disease's mortality and morbidity. Over time, the condition progresses from the pre-diabetic to the diabetic stage and then to the development of complications. Years and enormous resources are required to evaluate pharmacological interventions to prevent or delay the progression of disease or complications in humans. Appropriate screening models are required to gain a better understanding of both pathogenesis and potential therapeutic agents. Different species of animals are used to evaluate the pharmacological potentials and study the pathogenesis of the disease. Animal models are essential for research because they represent most of the structural, functional, and biochemical characteristics of human diseases. An ideal screening model should mimic the pathogenesis of the disease with identifiable characteristics. A thorough understanding of animal models is required for the experimental design to select an appropriate model. Each animal model has certain advantages and limitations. The present manuscript describes the animal models and their diagnostic characteristics to evaluate microvascular diabetic complications.
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8
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Wada I, Nakao S, Yamaguchi M, Kaizu Y, Arima M, Sawa S, Sonoda KH. Retinal VEGF-A Overexpression Is Not Sufficient to Induce Lymphangiogenesis Regardless of VEGF-C Upregulation and Lyve1+ Macrophage Infiltration. Invest Ophthalmol Vis Sci 2021; 62:17. [PMID: 34673901 PMCID: PMC8543389 DOI: 10.1167/iovs.62.13.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 09/23/2021] [Indexed: 11/24/2022] Open
Abstract
Purpose No lymphatic vessels have been identified in the retina. This study investigated whether pathological VEGF-A-overexpressing diabetic retina causes lymphangiogenesis. Methods Three genetic mouse models of diabetic retinopathy (DR) (Akita [Ins2+/-], Kimba [vegfa+/+], and Akimba [Akita × Kimba] mice) were used. Retinas were examined by fundus photography, fluorescence angiography (FA), and immunostaining to detect lymphangiogenesis or angiogenesis. Lyve1-GFP (Lyve1EGFP/Cre) mice were used to examine Lyve1-expressing cells by immunostaining. Lymphatic-related factors were investigated in mouse retina and vitreous fluid from proliferative diabetic retinopathy (PDR) patients by RT-PCR and ELISA, respectively. Aged Kimba and Akimba mice were used to examine the retinal phenotype at the late phase of VEGF overexpression. Results FA and immunostaining showed retinal neovascularization in Kimba and Akimba mice but not wild-type and Akita mice. Immunohistochemistry showed that lymphangiogenesis was not present in the retinas of Akita, Kimba, or Akimba mice despite the significant upregulation of lymphatic-related factors (Lyve1, podoplanin, VEGF-A, VEGF-C, VEGF-D, VEGFR2, and VEGFR3) in the retinas of Kimba and Akimba mice by RT-PCR (P < 0.005). Furthermore, lymphangiogenesis was not present in aged Kimba or Akimba mice. Significantly increased numbers of Lyve1-positive cells present in the retinas of Kimba and Akimba mice, especially in the peripheral areas, were CD11b positive, indicating a macrophage population (P < 0.005). VEGF-C in PDR vitreous with vitreous hemorrhage (VH) was higher than in PDR without VH or a macular hole. Conclusions Retinal VEGF-A overexpression did not cause typical lymphangiogenesis despite upregulated lymphatic-related factors and significant Lyve1-positive macrophage infiltration.
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Affiliation(s)
- Iori Wada
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Shintaro Nakao
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
- Department of Ophthalmology, National Hospital Organization, Kyushu Medical Center, Fukuoka, Japan
| | - Muneo Yamaguchi
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yoshihiro Kaizu
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Mitsuru Arima
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Shinichiro Sawa
- Division of Mucosal Immunology, Research Center for Systems Immunology, Kyushu University, Fukuoka, Japan
| | - Koh-Hei Sonoda
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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9
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Weigelt CM, Fuchs H, Schönberger T, Stierstorfer B, Strobel B, Lamla T, Ciossek T, Bakker RA, Redemann NH. AAV-Mediated Expression of Human VEGF, TNF-α, and IL-6 Induces Retinal Pathology in Mice. Transl Vis Sci Technol 2021; 10:15. [PMID: 34520511 PMCID: PMC8444492 DOI: 10.1167/tvst.10.11.15] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Retinopathies display complex pathologies, including vasculopathies, inflammation, and fibrosis, leading ultimately to visual impairment. However, animal models accurately reflecting these pathologies are lacking. In this study, we evaluate the suitability of using Adeno-associated virus (AAV)-mediated long-term expression of cytokines to establish retinal pathology in the murine retina. Methods We administered recombinant, Müller-glia targeted AAV-ShH10 into the mouse vitreous to induce retinal expression of either human vascular endothelial growth factor (VEGF)-A165, tumor necrosis factor alpha (TNF-α), or interleukin-6 (IL-6) and evaluated consequent effects by optical coherence tomography, fluorescein angiography, and histology. Results Intravitreal injection of AAVs resulted in rapid and stable expression of the transgenes within 1 to 6 weeks. Akin to the role of VEGF-A in wet age-related macular degeneration, expression of VEGF-A led to several vasculopathies in mice, including neovascularization and vascular leakage. In contrast, the expression of the proinflammatory cytokines TNF-α or IL-6 induced retinal inflammation, as indicated by microglial activation. Furthermore, the expression of TNF-α, but not of IL-6, induced immune cell infiltration into the vitreous as well as vasculitis, and subsequently induced the development of fibrosis and epiretinal membranes. Conclusions In summary, the long-term expression of human VEGF-A165, TNF-α, or IL-6 in the mouse eye induced specific pathologies within 6 weeks that mimic different aspects of human retinopathies. Translational Relevance AAV-mediated expression of human genes in mice is an attractive approach to provide valuable insights into the underlying molecular mechanisms causing retinopathies and is easily adaptable to other genes and preclinical species supporting drug discovery for retinal diseases.
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Affiliation(s)
- Carina M Weigelt
- Cardiometabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Holger Fuchs
- Cardiometabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Tanja Schönberger
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Birgit Stierstorfer
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Benjamin Strobel
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Thorsten Lamla
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Thomas Ciossek
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Remko A Bakker
- Cardiometabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Norbert H Redemann
- Cardiometabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
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10
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Sadasivam R, Packirisamy G, Shakya S, Goswami M. Non-invasive multimodal imaging of Diabetic Retinopathy: A survey on treatment methods and Nanotheranostics. Nanotheranostics 2021; 5:166-181. [PMID: 33564616 PMCID: PMC7868006 DOI: 10.7150/ntno.56015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 12/22/2020] [Indexed: 12/12/2022] Open
Abstract
Diabetes Retinopathy (DR) is one of the most prominent microvascular complications of diabetes. It is one of the pre-eminent causes for vision impairment followed by blindness among the working-age population worldwide. The de facto cause for DR remains challenging, despite several efforts made to unveil the mechanism underlying the pathology of DR. There is quite less availability of the low cost pre-emptive theranostic imaging tools in terms of in-depth resolution, due to the multiple factors involved in the etiology of DR. This review work comprehensively explores the various reports and research works on all perspectives of diabetic retinopathy (DR), and its mechanism. It also discusses various advanced non-destructive imaging modalities, current, and future treatment approaches. Further, the application of various nanoparticle-based drug delivery strategies used for the treatment of DR are also discussed. In a nutshell, the present review work bolsters the pursuit of the development of an advanced non-invasive optical imaging modal with a nano-theranostic approach for the future diagnosis and treatment of DR and its associated ocular complications.
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Affiliation(s)
- Rajkumar Sadasivam
- Divyadrishti Imaging Laboratory, Department of Physics, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand-247667, India
| | - Gopinath Packirisamy
- Nanobiotechnology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand-247667, India
| | - Snehlata Shakya
- Department of clinical physiology, Lund University, Skåne University Hospital, Skåne, Sweden
| | - Mayank Goswami
- Divyadrishti Imaging Laboratory, Department of Physics, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand-247667, India
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11
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Meng X, Zhang Y, Kong Q, Lv Y, Hu H, Chen T, Tang Z. Interaction analysis of systolic blood pressure and glycosylated hemoglobin in diabetic retinopathy: A Chinese sample. TRADITIONAL MEDICINE AND MODERN MEDICINE 2019. [DOI: 10.1142/s2575900019500101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Background: The objective of this study was to evaluate (1) the association of blood pressure (BP) profiles and glucose profiles with diabetic retinopathy (DR) and (2) the interaction between BP profiles and glucose profiles in DR in a Chinese sample. Methods: This was a cross-sectional study of 984 DR patients. Demographic data, BP profiles, glucose profiles, renal function parameters, and medical histories were recorded. All the participants underwent testing for DR with digital nonmydriatic fundus photography and image analysis, using a standardized protocol. A multiple variable logistic regression (MLR) was employed to detect the associations and interactions of BP profiles and glucose profiles with DR. Results: Systolic blood pressure (SBP) and glycated hemoglobin (HbA1c) were significantly correlated with DR ([Formula: see text] for SBP, [Formula: see text]; [Formula: see text] for HbA1c, [Formula: see text]). An interaction between SBP and HbA1c was detected in a multiple logistic regression (MLR) model after adjustment for relevant potential confounders ([Formula: see text], [Formula: see text]). Conclusion: The present study suggested that SBP and HbA1c were independently and significantly associated with DR and that SBP interacted with HbA1c to impact on DR.
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Affiliation(s)
- Xiangying Meng
- Department of Endocrinology, Dahua Hospital, Xuhui District, Shanghai, P. R. China
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, P. R. China
| | - Yuanhao Zhang
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, P. R. China
| | - Qing Kong
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, P. R. China
| | - Yubao Lv
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, P. R. China
- Institutes of Integrative Medicine, Fudan University, Shanghai, P. R. China
| | - Hailin Hu
- Department of Ophthalmology, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P. R. China
| | - Tao Chen
- Clinical Laboratory, Xindu Distict People’s Hospital, Chengdu, Sichuan, P. R. China
| | - Zihui Tang
- Department of Endocrinology, Dahua Hospital, Xuhui District, Shanghai, P. R. China
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, P. R. China
- Institutes of Integrative Medicine, Fudan University, Shanghai, P. R. China
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12
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Mechanisms Underlying Early-Stage Changes in Visual Performance and Retina Function After Experimental Induction of Sustained Dyslipidemia. Neurochem Res 2018; 43:1500-1510. [PMID: 29860619 DOI: 10.1007/s11064-018-2563-2] [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: 03/23/2018] [Revised: 05/21/2018] [Accepted: 05/26/2018] [Indexed: 12/12/2022]
Abstract
Visual and retinal function was measured in a mouse model of chemically induced, sustained dyslipidemia to determine the contribution of dyslipidemia to the pathogenesis of retinopathy in the context of metabolic syndrome. Fifteen male C57BL/6Crl mice were divided into three groups. Poloxamer 407 (P-407), 14.5% w/w was delivered at a rate of 6 µl/day by implanted osmotic mini-pumps either subcutaneously (P-407 SQ) or intraperitoneally (P-407 IP) to P-407-treated mice, whereas saline was administered at the same rate to control mice using only the subcutaneous route of administration. Total cholesterol (TC) and true triglyceride (TG) levels were quantified from plasma. Optomotor responses to stimuli of varying spatial frequency or contrast were used to measure visual acuity and contrast sensitivity. Retinal function was determined using Ganzfeld flash electroretinography (ERG). At 32 days, TC for the P-407 IP group was significantly elevated compared to saline controls (169.4 ± 16.5 mg/dl, 0.001 < P < 0.01). TG levels for both the P-407 SQ (59.3 ± 22.4 mg/dl, 0.01 < P < 0.05) and P-407 IP groups (67.7 ± 18.0 mg/dl, 0.001 < P < 0.01) were significantly elevated relative to controls. Electroretinography demonstrated a very significant decline in the b/a ratio (1.80 ± 0.11, P < 0.01) for the P-407 IP group. The b/a ratio exhibited a moderate, significant correlation with TC levels (r = - 0.4425, P = 0.0392) and a strong, very significant correlation with TG levels (r = - 0.6190, P = 0.0021). Delivery of P-407 via osmotic mini-pump resulted in the sustained, significant elevation of plasma TC and TG levels. This elevation in plasma lipid levels was correlated with a decline in inner retinal function.
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13
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Lau CML, Yu Y, Jahanmir G, Chau Y. Controlled release technology for anti-angiogenesis treatment of posterior eye diseases: Current status and challenges. Adv Drug Deliv Rev 2018; 126:145-161. [PMID: 29625138 DOI: 10.1016/j.addr.2018.03.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/25/2018] [Accepted: 03/27/2018] [Indexed: 12/27/2022]
Abstract
Antiangiogenic therapeutics, such as corticosteroids, VEGF targeting antibodies and aptamers have been demonstrated effective in controlling retinal and choroidal neovascularization related vision loss. However, to manage the chronic conditions, it requires long term and frequent intravitreal injections of these drugs, resulting in poor patient compliance and suboptimal treatment. In addition, emerging drugs such as tyrosine kinase inhibitors and siRNAs received much expectations, but the late stage clinical trials encountered various obstacles. Controlled release technology could improve the existing treatment regimen by extending therapeutic duration, reducing risks and burdens caused by frequent injections, and enabling new drugs to overcome the hurdles of translation. Here, we give qualitative and quantitative discussions about the principle mechanisms of polymeric reservoir, polymeric matrix and hydrogel systems. We also reveal the design rationales of the existing drug delivery and release systems in preclinical and clinical stages. Lastly, the animal models of ocular angiogenesis diseases are critically reviewed, which could help to facilitate the translation of controlled release technologies from bench to bedside.
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Affiliation(s)
- Chi Ming Laurence Lau
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Hong Kong
| | - Yu Yu
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Hong Kong; Pleryon Therapeutics Limited, Hong Kong
| | - Ghodsiehsadat Jahanmir
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Hong Kong
| | - Ying Chau
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Hong Kong; The Hong Kong University of Science and Technology Shenzhen Institute, Shenzhen 518057, China.
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14
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Chaurasia SS, Lim RR, Parikh BH, Wey YS, Tun BB, Wong TY, Luu CD, Agrawal R, Ghosh A, Mortellaro A, Rackoczy E, Mohan RR, Barathi VA. The NLRP3 Inflammasome May Contribute to Pathologic Neovascularization in the Advanced Stages of Diabetic Retinopathy. Sci Rep 2018; 8:2847. [PMID: 29434227 PMCID: PMC5809448 DOI: 10.1038/s41598-018-21198-z] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 01/29/2018] [Indexed: 12/11/2022] Open
Abstract
Diabetic retinopathy (DR) is a retinal microvascular disease characterized by inflammatory and angiogenic pathways. In this study, we evaluated NLRP3 inflammasome in a double transgenic mouse model, Akimba (Ins2 Akita xVEGF+/-), which demonstrates hyperglycemia, vascular hyperpermeability and neovascularization seen in the proliferative DR. Retinal structural integrity, vascular leakage and function were examined by fundus photography, fluorescein angiography, optical coherence tomography, retinal flat mounts, laser speckle flowgraphy (LSFG), and electroretinography in Akimba and its parental strains, Akita (Ins2 Akita ) and Kimba (trVEGF029) mice. Inflammatory mechanisms involving NLRP3 inflammasome were investigated using real time-PCR, immunohistochemistry, ELISA and western blots. We observed an increased vascular leakage, reduced retinal thickness, and function in Akimba retina. Also, Akimba retina depicts decreased relative flow volume measured by LSFG. Most importantly, high levels of IL-1β along with increased NLRP3, ASC, and Caspase-1 at mRNA and protein levels were observed in Akimba retina. However, the in vivo functional role remains undefined. In conclusion, increased activation of macroglia (GFAP), microglia (Iba-1 and OX-42) and perivascular macrophages (F4/80 and CD14) together with pro-inflammatory (IL-1β and IL-6) and pro-angiogenic markers (PECAM-1, ICAM-1, VEGF, Flt-1, and Flk-1), suggested a critical role for NLRP3 inflammasome in the Akimba mouse model depicting advanced stages of DR pathogenesis.
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Affiliation(s)
- Shyam S Chaurasia
- Ocular Immunology and Angiogenesis Lab, Department of Veterinary Medicine & Surgery, University of Missouri, Columbia, MO, USA.
- Department of Biomedical Sciences, University of Missouri, Columbia, MO, USA.
- Ophthalmology, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA.
| | - Rayne R Lim
- Ocular Immunology and Angiogenesis Lab, Department of Veterinary Medicine & Surgery, University of Missouri, Columbia, MO, USA
- Department of Biomedical Sciences, University of Missouri, Columbia, MO, USA
- Ophthalmology, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA
| | - Bhav H Parikh
- Translational Pre-Clinical Model Platform, Singapore Eye Research Institute, Singapore, Singapore
| | - Yeo Sia Wey
- Translational Pre-Clinical Model Platform, Singapore Eye Research Institute, Singapore, Singapore
| | - Bo Bo Tun
- Translational Pre-Clinical Model Platform, Singapore Eye Research Institute, Singapore, Singapore
| | - Tien Yin Wong
- Translational Pre-Clinical Model Platform, Singapore Eye Research Institute, Singapore, Singapore
- The Ophthalmology & Visual Sciences Academic Clinical Program, DUKE-NUS Graduate Medical School, Singapore, Singapore
| | - Chi D Luu
- Centre for Eye Research Australia, Department of Surgery (Ophthalmology), University of Melbourne, Melbourne, Australia
| | - Rupesh Agrawal
- National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore, Singapore
| | | | - Alessandra Mortellaro
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Elizabeth Rackoczy
- Centre for Ophthalmology and Visual Sciences, University of Western Australia, Perth, WA, 6009, Australia
| | - Rajiv R Mohan
- Ocular Immunology and Angiogenesis Lab, Department of Veterinary Medicine & Surgery, University of Missouri, Columbia, MO, USA
- Department of Biomedical Sciences, University of Missouri, Columbia, MO, USA
- Ophthalmology, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA
- Mason Eye Institute, University of Missouri, Columbia, MO, USA
| | - Veluchamy A Barathi
- Translational Pre-Clinical Model Platform, Singapore Eye Research Institute, Singapore, Singapore
- The Ophthalmology & Visual Sciences Academic Clinical Program, DUKE-NUS Graduate Medical School, Singapore, Singapore
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15
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Imai A, Toriyama Y, Iesato Y, Hirabayashi K, Sakurai T, Kamiyoshi A, Ichikawa-Shindo Y, Kawate H, Tanaka M, Liu T, Xian X, Zhai L, Dai K, Tanimura K, Liu T, Cui N, Yamauchi A, Murata T, Shindo T. Adrenomedullin Suppresses Vascular Endothelial Growth Factor-Induced Vascular Hyperpermeability and Inflammation in Retinopathy. THE AMERICAN JOURNAL OF PATHOLOGY 2017; 187:999-1015. [PMID: 28322199 DOI: 10.1016/j.ajpath.2017.01.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 01/19/2017] [Indexed: 11/29/2022]
Abstract
Diabetic macular edema (DME) is caused by blood-retinal barrier breakdown associated with retinal vascular hyperpermeability and inflammation, and it is the major cause of visual dysfunction in diabetic retinopathy. Adrenomedullin (ADM) is an endogenous peptide first identified as a strong vasodilator. ADM is expressed in the eyes and is up-regulated in various eye diseases, although the pathophysiological significance is largely unknown. We investigated the effect of ADM on DME. In Kimba mice, which overexpress human vascular endothelial growth factor in their retinas, the capillary dropout, vascular leakage, and vascular fragility characteristic of diabetic retinopathy were observed. Intravitreal or systemic administration of ADM to Kimba mice ameliorated both the capillary dropout and vascular leakage. Evaluation of the transendothelial electrical resistance and fluorescein isothiocyanate-dextran permeability of an endothelial cell monolayer using TR-iBRB retinal capillary endothelial cells revealed that vascular endothelial growth factor enhanced vascular permeability but that co-administration of ADM suppressed the effect, in part by enhancing tight junction formation between endothelial cells. In addition, a comprehensive PCR array analysis showed that ADM administration suppressed various molecules related to inflammation and NF-κB signaling within retinas. From these results, we suggest that by exerting inhibitory effects on retinal inflammation, vascular permeability, and blood-retinal barrier breakdown, ADM could serve as a novel therapeutic agent for the treatment of DME.
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Affiliation(s)
- Akira Imai
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan; Department of Ophthalmology, Shinshu University School of Medicine, Nagano, Japan
| | - Yuichi Toriyama
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan; Department of Ophthalmology, Shinshu University School of Medicine, Nagano, Japan
| | - Yasuhiro Iesato
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan; Department of Ophthalmology, Shinshu University School of Medicine, Nagano, Japan
| | - Kazutaka Hirabayashi
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan; Department of Ophthalmology, Shinshu University School of Medicine, Nagano, Japan
| | - Takayuki Sakurai
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Akiko Kamiyoshi
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Yuka Ichikawa-Shindo
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Hisaka Kawate
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Megumu Tanaka
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Tian Liu
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Xian Xian
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Liuyu Zhai
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Kun Dai
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Keiya Tanimura
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Teng Liu
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | - Nanqi Cui
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan
| | | | - Toshinori Murata
- Department of Ophthalmology, Shinshu University School of Medicine, Nagano, Japan
| | - Takayuki Shindo
- Department of Cardiovascular Research, Shinshu University Graduate School of Medicine, Nagano, Japan.
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16
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Pradhan P, Upadhyay N, Tiwari A, Singh LP. Genetic and epigenetic modifications in the pathogenesis of diabetic retinopathy: a molecular link to regulate gene expression. ACTA ACUST UNITED AC 2016; 2:192-204. [PMID: 28691104 DOI: 10.15761/nfo.1000145] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Intensification in the frequency of diabetes and the associated vascular complications has been a root cause of blindness and visual impairment worldwide. One such vascular complication which has been the prominent cause of blindness; retinal vasculature, neuronal and glial abnormalities is diabetic retinopathy (DR), a chronic complicated outcome of Type 1 and Type 2 diabetes. It has also become clear that "genetic" variations in population alone can't explain the development and progression of diabetes and its complications including DR. DR experiences engagement of foremost mediators of diabetes such as hyperglycemia, oxidant stress, and inflammatory factors that lead to the dysregulation of "epigenetic" mechanisms involving histone acetylation and histone and DNA methylation, chromatin remodeling and expression of a complex set of stress-regulated and disease-associated genes. In addition, both elevated glucose concentration and insulin resistance leave a robust effect on epigenetic reprogramming of the endothelial cells too, since endothelium associated with the eye aids in maintaining the vascular homeostasis. Furthermore, several studies conducted on the disease suggest that the modifications of the epigenome might be the fundamental mechanism(s) for the proposed metabolic memory' resulting into prolonged gene expression for inflammation and cellular dysfunction even after attaining the glycemic control in diabetics. Henceforth, the present review focuses on the aspects of genetic and epigenetic alterations in genes such as vascular endothelial growth factor and aldose reductase considered being associated with DR. In addition, we discuss briefly the role of the thioredoxin-interacting protein TXNIP, which is strongly induced by high glucose and diabetes, in cellular oxidative stress and mitochondrial dysfunction potentially leading to chromatin remodeling and ocular complications of diabetes. The identification of disease-associated genes and their epigenetic regulations will lead to potential new drugs and gene therapies as well as personalized medicine to prevent or slow down the progression of DR.
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Affiliation(s)
- Priya Pradhan
- School of Biotechnology, Rajiv Gandhi Technical University, Bhopal, Madhya Pradesh, India
| | - Nisha Upadhyay
- School of Biotechnology, Rajiv Gandhi Technical University, Bhopal, Madhya Pradesh, India
| | - Archana Tiwari
- School of Biotechnology, Rajiv Gandhi Technical University, Bhopal, Madhya Pradesh, India
| | - Lalit P Singh
- Departments of Anatomy/Cell Biology and Ophthalmology, School of Medicine, Wayne State University, Detroit, MI, USA
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17
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Pini A, Obara I, Battell E, Chazot PL, Rosa AC. Histamine in diabetes: Is it time to reconsider? Pharmacol Res 2016; 111:316-324. [DOI: 10.1016/j.phrs.2016.06.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 06/20/2016] [Accepted: 06/21/2016] [Indexed: 10/21/2022]
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18
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Binz N, Rakoczy EP, Ali Rahman IS, Vagaja NN, Lai CM. Biomarkers for Diabetic Retinopathy - Could Endothelin 2 Be Part of the Answer? PLoS One 2016; 11:e0160442. [PMID: 27482904 PMCID: PMC4970817 DOI: 10.1371/journal.pone.0160442] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 07/19/2016] [Indexed: 12/17/2022] Open
Abstract
Purpose The endothelins are a family of three highly conserved and homologous vasoactive peptides that are expressed across all organ systems. Endothelin (Edn) dysregulation has been implicated in a number of pathophysiologies, including diabetes and diabetes-related complications. Here we examined Edn2 and endothelin receptor B (Endrb) expression in retinae of diabetic mouse models and measured serum Edn2 to assess its biomarker potential. Materials and Methods Edn2 and Ednrb mRNA and Edn2 protein expression were assessed in young (8wk) and mature (24wk) C57Bl/6 (wild type; wt), Kimba (model of retinal neovascularisation, RNV), Akita (Type 1 diabetes; T1D) and Akimba mice (T1D plus RNV) by qRT-PCR and immunohistochemistry. Edn2 protein concentration in serum was measured using ELISA. Results Fold-changes in Edn2 and Ednrb mRNA were seen only in young Kimba (Edn2: 5.3; Ednrb: 6.0) and young Akimba (Edn2: 7.9, Ednrb: 8.8) and in mature Kimba (Edn2:9.2, Ednrb:11.2) and mature Akimba (Edn2:14.0, Ednrb:17.5) mice. Co-localisation of Edn2 with Müller-cell-specific glutamine synthetase demonstrated Müller cells and photoreceptors as the major cell types for Edn2 expression in all animal models. Edn2 serum concentrations in young Kimba, Akita and Akimba mice were not elevated compared to wt. However, in mature mice, Edn2 serum concentration was increased in Akimba (6.9pg/mg total serum protein) compared to wt, Kimba and Akita mice (3.9, 4.6, and 3.8pg/mg total serum protein, respectively; p<0.05). Conclusions These results demonstrated that long-term hyperglycaemia in conjunction with VEGF-driven RNV increased Edn2 serum concentration suggesting Edn2 might be a candidate biomarker for vascular changes in diabetic retinopathy.
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MESH Headings
- Animals
- Biomarkers/blood
- Blood Glucose/metabolism
- Diabetes Mellitus, Type 1/blood
- Diabetes Mellitus, Type 1/diagnosis
- Diabetes Mellitus, Type 1/genetics
- Diabetes Mellitus, Type 1/pathology
- Disease Models, Animal
- Endothelin-2/blood
- Endothelin-2/genetics
- Ependymoglial Cells/metabolism
- Ependymoglial Cells/pathology
- Gene Expression
- Glycated Hemoglobin/metabolism
- Hyperglycemia/blood
- Hyperglycemia/diagnosis
- Hyperglycemia/genetics
- Hyperglycemia/pathology
- Mice
- Mice, Inbred C57BL
- Mice, Inbred Strains
- Photoreceptor Cells, Vertebrate/metabolism
- Photoreceptor Cells, Vertebrate/pathology
- RNA, Messenger/blood
- RNA, Messenger/genetics
- Receptor, Endothelin B/blood
- Receptor, Endothelin B/genetics
- Retinal Neovascularization/blood
- Retinal Neovascularization/diagnosis
- Retinal Neovascularization/genetics
- Retinal Neovascularization/pathology
- Vascular Endothelial Growth Factor A/blood
- Vascular Endothelial Growth Factor A/genetics
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Affiliation(s)
- Nicolette Binz
- Molecular Ophthalmology, Lions Eye Institute, Nedlands, WA, 6009, Australia
| | - Elizabeth P. Rakoczy
- Molecular Ophthalmology, Lions Eye Institute, Nedlands, WA, 6009, Australia
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, WA, 6009, Australia
- * E-mail:
| | - Ireni S. Ali Rahman
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Nermina N. Vagaja
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Chooi-May Lai
- Molecular Ophthalmology, Lions Eye Institute, Nedlands, WA, 6009, Australia
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, WA, 6009, Australia
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19
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Lange C, Storkebaum E, de Almodóvar CR, Dewerchin M, Carmeliet P. Vascular endothelial growth factor: a neurovascular target in neurological diseases. Nat Rev Neurol 2016; 12:439-54. [PMID: 27364743 DOI: 10.1038/nrneurol.2016.88] [Citation(s) in RCA: 226] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Brain function critically relies on blood vessels to supply oxygen and nutrients, to establish a barrier for neurotoxic substances, and to clear waste products. The archetypal vascular endothelial growth factor, VEGF, arose in evolution as a signal affecting neural cells, but was later co-opted by blood vessels to regulate vascular function. Consequently, VEGF represents an attractive target to modulate brain function at the neurovascular interface. On the one hand, VEGF is neuroprotective, through direct effects on neural cells and their progenitors and indirect effects on brain perfusion. In accordance, preclinical studies show beneficial effects of VEGF administration in neurodegenerative diseases, peripheral neuropathies and epilepsy. On the other hand, pathologically elevated VEGF levels enhance vessel permeability and leakage, and disrupt blood-brain barrier integrity, as in demyelinating diseases, for which blockade of VEGF may be beneficial. Here, we summarize current knowledge on the role and therapeutic potential of VEGF in neurological diseases.
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Affiliation(s)
- Christian Lange
- Laboratory of Angiogenesis and Vascular Metabolism, Vesalius Research Center, Department of Oncology (KU Leuven) and Vesalius Research Center (VIB), Campus Gasthuisberg O&N4, Herestraat 49 - 912, B-3000, Leuven, Belgium
| | - Erik Storkebaum
- Molecular Neurogenetics Laboratory, Max Planck Institute for Molecular Biomedicine, Roentgenstrasse 20, D-48149 Muenster, Germany.,Faculty of Medicine, University of Muenster, Roentgenstrasse 20, D-48149 Muenster, Germany
| | | | - Mieke Dewerchin
- Laboratory of Angiogenesis and Vascular Metabolism, Vesalius Research Center, Department of Oncology (KU Leuven) and Vesalius Research Center (VIB), Campus Gasthuisberg O&N4, Herestraat 49 - 912, B-3000, Leuven, Belgium
| | - Peter Carmeliet
- Laboratory of Angiogenesis and Vascular Metabolism, Vesalius Research Center, Department of Oncology (KU Leuven) and Vesalius Research Center (VIB), Campus Gasthuisberg O&N4, Herestraat 49 - 912, B-3000, Leuven, Belgium
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20
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Cai X, McGinnis JF. Diabetic Retinopathy: Animal Models, Therapies, and Perspectives. J Diabetes Res 2016; 2016:3789217. [PMID: 26881246 PMCID: PMC4736804 DOI: 10.1155/2016/3789217] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 12/06/2015] [Indexed: 12/12/2022] Open
Abstract
Diabetic retinopathy (DR) is one of the major complications of diabetes. Although great efforts have been made to uncover the mechanisms underlying the pathology of DR, the exact causes of DR remain largely unknown. Because of multifactor involvement in DR etiology, currently no effective therapeutic treatments for DR are available. In this paper, we review the pathology of DR, commonly used animal models, and novel therapeutic approaches. Perspectives and future directions for DR treatment are discussed.
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Affiliation(s)
- Xue Cai
- Department of Ophthalmology, Dean McGee Eye Institute, Oklahoma University Health Sciences Center, Oklahoma City, OK 73104, USA
- *Xue Cai: and
| | - James F. McGinnis
- Department of Ophthalmology, Dean McGee Eye Institute, Oklahoma University Health Sciences Center, Oklahoma City, OK 73104, USA
- Department of Cell Biology, Oklahoma University Health Sciences Center, Oklahoma City, OK 73104, USA
- Oklahoma Center for Neuroscience, Oklahoma University Health Sciences Center, Oklahoma City, OK 73104, USA
- *James F. McGinnis:
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21
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Guyot M, Pagès G. VEGF Splicing and the Role of VEGF Splice Variants: From Physiological-Pathological Conditions to Specific Pre-mRNA Splicing. Methods Mol Biol 2015; 1332:3-23. [PMID: 26285742 DOI: 10.1007/978-1-4939-2917-7_1] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
During this past decade, the vascular endothelial growth factor (VEGF) pathway has been extensively studied. VEGF is a paradigm of molecular regulation since its expression is controlled at all possible steps including transcription, mRNA stability, translation, and pre-mRNA splicing. The latter form of molecular regulation is probably the least studied. This field has been neglected; yet different forms of VEGF with different sizes and different physiological properties issued from alternative splicing have been described a long time ago. Recently a new level of complexity was added to the field of splicing of VEGF pre-mRNA. Whereas thousands of publications have described VEGF as a pro-angiogenic factor, an alternative splicing event generates specific anti-angiogenic forms of VEGF that only differ from the others by a modification in the last six amino acids of the protein. According to the scientists who discovered these isoforms, which are indistinguishable from the pro-angiogenic ones with pan VEGF antibodies, some of the literature on VEGF is at least inexact if not completely false. Moreover, the presence of anti-angiogenic forms of VEGF may explain the disappointing efficacy of anti-VEGF therapies on the overall survival of patients with different forms of cancers and with wet age-related macular degeneration. This review focuses on the existence of the different alternative splice variants of VEGF and the molecular mechanisms associated with their expression and function.
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Affiliation(s)
- Mélanie Guyot
- Institute for Research on Cancer and Aging of Nice (IRCAN), University of Nice Sophia Antipolis, Centre Antoine Lacassagne 33 Avenue de Valombrose, UMR CNRS 7284/INSERM U 1081, Nice, 06189, France
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Hasegawa E, Sweigard H, Husain D, Olivares AM, Chang B, Smith KE, Birsner AE, D’Amato RJ, Michaud NA, Han Y, Vavvas DG, Miller JW, Haider NB, Connor KM. Characterization of a spontaneous retinal neovascular mouse model. PLoS One 2014; 9:e106507. [PMID: 25188381 PMCID: PMC4154693 DOI: 10.1371/journal.pone.0106507] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 08/01/2014] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Vision loss due to vascular disease of the retina is a leading cause of blindness in the world. Retinal angiomatous proliferation (RAP) is a subgroup of neovascular age-related macular degeneration (AMD), whereby abnormal blood vessels develop in the retina leading to debilitating vision loss and eventual blindness. The novel mouse strain, neoretinal vascularization 2 (NRV2), shows spontaneous fundus changes associated with abnormal neovascularization. The purpose of this study is to characterize the induction of pathologic angiogenesis in this mouse model. METHODS The NRV2 mice were examined from postnatal day 12 (p12) to 3 months. The phenotypic changes within the retina were evaluated by fundus photography, fluorescein angiography, optical coherence tomography, and immunohistochemical and electron microscopic analysis. The pathological neovascularization was imaged by confocal microscopy and reconstructed using three-dimensional image analysis software. RESULTS We found that NRV2 mice develop multifocal retinal depigmentation in the posterior fundus. Depigmented lesions developed vascular leakage observed by fluorescein angiography. The spontaneous angiogenesis arose from the retinal vascular plexus at postnatal day (p)15 and extended toward retinal pigment epithelium (RPE). By three months of age, histological analysis revealed encapsulation of the neovascular lesion by the RPE in the photoreceptor cell layer and subretinal space. CONCLUSIONS The NRV2 mouse strain develops early neovascular lesions within the retina, which grow downward towards the RPE beginning at p15. This retinal neovascularization model mimics early stages of human retinal angiomatous proliferation (RAP) and will likely be a useful in elucidating targeted therapeutics for patients with ocular neovascular disease.
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Affiliation(s)
- Eiichi Hasegawa
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Harry Sweigard
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Deeba Husain
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ana M. Olivares
- Schepens Eye Research Institute, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
| | - Bo Chang
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Kaylee E. Smith
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
| | - Amy E. Birsner
- Vascular Biology Program, Department of Surgery, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Robert J. D’Amato
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
- Vascular Biology Program, Department of Surgery, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Norman A. Michaud
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
| | - Yinan Han
- Schepens Eye Research Institute, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
| | - Demetrios G. Vavvas
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Joan W. Miller
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Neena B. Haider
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
- Schepens Eye Research Institute, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
| | - Kip M. Connor
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts, United States of America
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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Jo DH, Cho CS, Kim JH, Jun HO, Kim JH. Animal models of diabetic retinopathy: doors to investigate pathogenesis and potential therapeutics. J Biomed Sci 2013; 20:38. [PMID: 23786217 PMCID: PMC3694455 DOI: 10.1186/1423-0127-20-38] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Accepted: 06/17/2013] [Indexed: 12/20/2022] Open
Abstract
Effective and validated animal models are valuable to investigate the pathogenesis and potential therapeutics for human diseases. There is much concern for diabetic retinopathy (DR) in that it affects substantial number of working population all around the world, resulting in visual deterioration and social deprivation. In this review, we discuss animal models of DR based on different species of animals from zebrafish to monkeys and prerequisites for animal models. Despite criticisms on imprudent use of laboratory animals, we hope that animal models of DR will be appropriately utilized to deepen our understanding on the pathogenesis of DR and to support our struggle to find novel therapeutics against catastrophic visual loss from DR.
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Affiliation(s)
- Dong Hyun Jo
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University, Seoul 110-744, Republic of Korea
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Charbel Issa P, Gillies MC, Chew EY, Bird AC, Heeren TFC, Peto T, Holz FG, Scholl HPN. Macular telangiectasia type 2. Prog Retin Eye Res 2012; 34:49-77. [PMID: 23219692 DOI: 10.1016/j.preteyeres.2012.11.002] [Citation(s) in RCA: 261] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Revised: 11/12/2012] [Accepted: 11/14/2012] [Indexed: 12/22/2022]
Abstract
Macular telangiectasia type 2 is a bilateral disease of unknown cause with characteristic alterations of the macular capillary network and neurosensory atrophy. Its prevalence may be underestimated and has recently been shown to be as high as 0.1% in persons 40 years and older. Biomicroscopy may show reduced retinal transparency, crystalline deposits, mildly ectatic capillaries, blunted venules, retinal pigment plaques, foveal atrophy, and neovascular complexes. Fluorescein angiography shows telangiectatic capillaries predominantly temporal to the foveola in the early phase and a diffuse hyperfluorescence in the late phase. High-resolution optical coherence tomography (OCT) may reveal disruption of the photoreceptor inner segment-outer segment border, hyporeflective cavities at the level of the inner or outer retina, and atrophy of the retina in later stages. Macular telangiectasia type 2 shows a unique depletion of the macular pigment in the central retina and recent therapeutic trials showed that such depleted areas cannot re-accumulate lutein and zeaxanthin after oral supplementation. There have been various therapeutic approaches with limited or no efficacy. Recent clinical trials with compounds that block vascular endothelial growth factor (VEGF) have established the role of VEGF in the pathophysiology of the disease, but have not shown significant efficacy, at least for the non-neovascular disease stages. Recent progress in structure-function correlation may help to develop surrogate outcome measures for future clinical trials. In this review article, we summarize the current knowledge on macular telangiectasia type 2, including the epidemiology, the genetics, the clinical findings, the staging and the differential diagnosis of the disease. Findings using retinal imaging are discussed, including fluorescein angiography, OCT, adaptive optics imaging, confocal scanning laser ophthalmoscopy, and fundus autofluorescence, as are the findings using visual function testing including visual acuity and fundus-controlled microperimetry. We provide an overview of the therapeutic approaches for both non-neovascular and neovascular disease stages and provide a perspective of future directions including animal models and potential therapeutic approaches.
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Affiliation(s)
- Peter Charbel Issa
- Department of Ophthalmology, University of Bonn, Ernst-Abbe-Str. 2, 53127 Bonn, Germany.
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25
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Binz N, Ali Rahman IS, Chinnery HR, McKeone R, Simpson KM, Speed TP, Lai CM, Rakoczy PE. Effect of vascular endothelial growth factor upregulation on retinal gene expression in the Kimba mouse. Clin Exp Ophthalmol 2012; 41:251-62. [PMID: 22788671 DOI: 10.1111/j.1442-9071.2012.02845.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND The Kimba mouse carries a human vascular endothelial growth factor transgene causing retinal neovascularisation similar to that seen in diabetic retinopathy. Here, we examine the relationship between differential gene expression induced by vascular endothelial growth factor overexpression and the architectural changes that occur in the retinae of these mice. METHODS Retinal gene expression changes in juvenile and adult Kimba mice were assayed by microarray and compared with age-matched wild-type littermates. Transcription of selected genes was validated by quantitative real-time polymerase chain reaction. Protein translation was determined using immunohistochemistry and enzyme-linked immunosorbent assay. RESULTS Semaphorin 3C was upregulated, and nuclear receptor subfamily 2, group 3, member 3 (Nr2e3) was downregulated in juvenile Kimba mice. Betacellulin and endothelin 2 were upregulated in adults. Semaphorin 3C colocalized with glial fibrillary acidic protein in Müller cells of Kimba retinae at greater signal intensities than in wild type. Endothelin 2 colocalised to Müller cell end feet and extended into the outer limiting membrane. Endothelin receptor type B staining was most pronounced in the inner nuclear layer, the region containing Müller cell somata. CONCLUSIONS An early spike in vascular endothelial growth factor induced significant long-term retinal neovascularisation associated with changes to the retinal ganglion, photoreceptor and Müller cells. Overexpression of vascular endothelial growth factor led to dysregulation of photoreceptor metabolism through differential expression of Nr2e3, endothelin 2, betacellulin and semaphorin 3C. Alterations in the expression of these genes may therefore play key roles in the pathological mechanisms that result from retinal neovascularisation.
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Affiliation(s)
- Nicolette Binz
- Department of Molecular Ophthalmology, Lions Eye Institute, Nedlands Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, Western Australia
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Cai X, Sezate SA, McGinnis JF. Neovascularization: ocular diseases, animal models and therapies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 723:245-52. [PMID: 22183339 DOI: 10.1007/978-1-4614-0631-0_32] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Affiliation(s)
- Xue Cai
- Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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27
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Preclinical safety evaluation of subretinal AAV2.sFlt-1 in non-human primates. Gene Ther 2011; 19:999-1009. [DOI: 10.1038/gt.2011.169] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Ali Rahman IS, Li CR, Lai CM, Rakoczy EP. In VivoMonitoring of VEGF-Induced Retinal Damage in the Kimba Mouse Model of Retinal Neovascularization. Curr Eye Res 2011; 36:654-62. [DOI: 10.3109/02713683.2010.551172] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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29
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Rakoczy EP, Ali Rahman IS, Binz N, Li CR, Vagaja NN, de Pinho M, Lai CM. Characterization of a mouse model of hyperglycemia and retinal neovascularization. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:2659-70. [PMID: 20829433 DOI: 10.2353/ajpath.2010.090883] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
One of the limitations of research into diabetic retinopathy is the lack of suitable animal models. To study how the two important factors--hyperglycemia and vascular endothelial growth factor--interact in diabetic retinopathy, the Akimba mouse (Ins2AkitaVEGF+/-) was generated by crossing the Akita mouse (Ins2Akita) with the Kimba mouse (VEGF+/+). C57Bl/6 and the parental and Akimba mouse lines were characterized by biometric measurements, histology, immunohistochemistry, and Spectralis Heidelberg retinal angiography and optical coherence tomography. The Akimba line not only retained the characteristics of the parental strains, such as developing hyperglycemia and retinal neovascularization, but developed higher blood glucose levels at a younger age and had worse kidney-body weight ratios than the Akita line. With aging, the Akimba line demonstrated enhanced photoreceptor cell loss, thinning of the retina, and more severe retinal vascular pathology, including more severe capillary nonperfusion, vessel constriction, beading, neovascularization, fibroses, and edema, compared with the Kimba line. The vascular changes were associated with major histocompatibility complex class II+ cellular staining throughout the retina. Together, these observations suggest that hyperglycemia resulted in higher prevalences of edema and exacerbated the vascular endothelial growth factor-driven neovascular and retinal changes in the Akimba line. Thus, the Akimba line could become a useful model for studying the interplay between hyperglycemia and vascular endothelial growth factor and for testing treatment strategies for potentially blinding complications, such as edema.
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Affiliation(s)
- Elizabeth P Rakoczy
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, Australia.
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30
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Grossniklaus HE, Kang SJ, Berglin L. Animal models of choroidal and retinal neovascularization. Prog Retin Eye Res 2010; 29:500-19. [PMID: 20488255 DOI: 10.1016/j.preteyeres.2010.05.003] [Citation(s) in RCA: 261] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
There have been numerous types of animal models of choroidal neovascularization (CNV) and retinal neovascularization (RNV). Understanding the pathobiology of CNV and RNV is important when evaluating and utilizing these models. Both CNV and RNV are dynamic processes. A break or defect in Bruchs' membrane is necessary for CNV to develop. This may be induced with a laser, mechanically via surgery, or in the setting of transgenic mice. Some of the transgenic mouse models spontaneously develop RNV and/or retinal angiomatous proliferation (RAP)-like lesions. The pathogenesis of RNV is well-known and is generally related to ischemic retinopathy. Models of oxygen-induced retinopathy (OIR) closely resemble retinopathy of prematurity (ROP). The streptozotocin (STZ) rat model develops features similar to diabetic retinopathy. This review summarizes general categories and specific examples of animal models of CNV and RNV. There are no perfect models of CNV or RNV and individual investigators are encouraged to choose the model that best suits their needs.
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31
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Bai Y, Ma JX, Guo J, Wang J, Zhu M, Chen Y, Le YZ. Müller cell-derived VEGF is a significant contributor to retinal neovascularization. J Pathol 2010; 219:446-54. [PMID: 19768732 DOI: 10.1002/path.2611] [Citation(s) in RCA: 162] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Vascular endothelial growth factor (VEGF-A) is a major pathogenic factor and a therapeutic target for age-related macular degeneration, diabetic retinopathy, and retinopathy of prematurity. Despite intensive effort in the field, the cellular mechanisms of VEGF action remain virtually uninvestigated. This situation makes it difficult to design cellular target-based therapeutics for these diseases. In light of the recent finding that VEGF is a potential neurotrophic factor, revealing the cellular mechanisms of VEGF action becomes necessary to preserve its beneficial effect and inhibit its pathological function in long-term anti-VEGF therapeutics for ocular vascular diseases. We therefore generated conditional VEGF knockout mice with an inducible Cre/lox system and determined the significance of Müller cell-derived VEGF in retinal development and maintenance and ischaemia-induced neovascularizartion and vascular leakage. Retinal development in the conditional VEGF knockout mice was analysed by examining retinal and choroidal vasculatures and retinal morphology and function. Ischaemia-induced retinal neovascularization and vascular leakage in the conditional VEGF knockout mice were analysed with fluorescein angiography, quantification of proliferative neovascular cells, immunohistochemistry, and immunoblotting using an oxygen-induced retinopathy model. Our results demonstrated that disruption of Müller cell-derived VEGF resulted in no apparent defects in retinal and choroidal vasculatures and retinal morphology and function, significant inhibition of the ischaemia-induced retinal neovascularization and vascular leakage, and attenuation of the ischaemia-induced breakdown of the blood-retina barrier. These results suggest that the retinal Müller cell-derived VEGF is a major contributor to ischaemia-induced retinal vascular leakage and pre-retinal and intra-retinal neovascularization. The observation that a significant, but not complete, reduction of VEGF in the retina does not cause detectable retinal degeneration suggests that appropriate doses of anti-VEGF agents may be important to the safe treatment of retinal vascular diseases.
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Affiliation(s)
- Yanyan Bai
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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Martinez R, Fierro CA, Shireman PK, Han HC. Mechanical buckling of veins under internal pressure. Ann Biomed Eng 2010; 38:1345-53. [PMID: 20094913 DOI: 10.1007/s10439-010-9929-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Accepted: 01/12/2010] [Indexed: 11/25/2022]
Abstract
Venous tortuosity is associated with multiple disease states and is often thought to be a consequence of venous hypertension and chronic venous disease. However, the underlying mechanisms of vein tortuosity are unclear. We hypothesized that increased pressure causes vein buckling that leads to a tortuous appearance. The specific aim of this study was to determine the critical buckling pressure of veins. We determined the buckling pressure of porcine jugular veins and measured the mechanical properties of these veins. Our results showed that the veins buckle when the transmural pressure exceeds a critical pressure that is strongly related to the axial stretch ratio in the veins. The critical pressures of the eight veins tested were 14.2 +/- 5.4 and 26.4 +/- 9.0 mmHg at axial stretch ratio 1.5 and 1.7, respectively. In conclusion, veins buckle into a tortuous shape at high lumen pressures or reduced axial stretch ratios. Our results are useful in understanding the development of venous tortuosity associated with varicose veins, venous valvular insufficiency, diabetic retinopathy, and vein grafts.
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Affiliation(s)
- Ricky Martinez
- Department of Mechanical Engineering, The University of Texas at San Antonio, San Antonio, TX 78249, USA
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Abstract
Increasing interest in developing reliable and reproducible models to study angiogenesis has emerged due to recent advances in the treatment of eye disease with pathologic angiogenesis. This review provides a summary of the principal ocular animal models for angiogenesis. Models of anterior segment neovascularization include the corneal micropocket assay, used to study the influence of specific molecules/proteins in angiogenesis, and corneal chemical and suture induced injury, which mimic more closely the complex nature of the human disease. Angiogenesis models of the posterior segment include the well-known laser-induced injury of the choroid/Bruch's membrane, as well as the oxygen induced retinopathy and models of injections of pro-angiogenic/inflammatory molecules. In addition, knockout or knock-in transgenic mice provide powerful tools in studying the role of specific proteins in angiogenesis.
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Affiliation(s)
- Sandra R Montezuma
- Retina Service, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA. sandra
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34
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Ruiz de Almodovar C, Lambrechts D, Mazzone M, Carmeliet P. Role and therapeutic potential of VEGF in the nervous system. Physiol Rev 2009; 89:607-48. [PMID: 19342615 DOI: 10.1152/physrev.00031.2008] [Citation(s) in RCA: 337] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The development of the nervous and vascular systems constitutes primary events in the evolution of the animal kingdom; the former provides electrical stimuli and coordination, while the latter supplies oxygen and nutrients. Both systems have more in common than originally anticipated. Perhaps the most striking observation is that angiogenic factors, when deregulated, contribute to various neurological disorders, such as neurodegeneration, and might be useful for the treatment of some of these pathologies. The prototypic example of this cross-talk between nerves and vessels is the vascular endothelial growth factor or VEGF. Although originally described as a key angiogenic factor, it is now well established that VEGF also plays a crucial role in the nervous system. We describe the molecular properties of VEGF and its receptors and review the current knowledge of its different functions and therapeutic potential in the nervous system during development, health, disease and in medicine.
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Al-Kateb H, Mirea L, Xie X, Sun L, Liu M, Chen H, Bull SB, Boright AP, Paterson AD. Multiple variants in vascular endothelial growth factor (VEGFA) are risk factors for time to severe retinopathy in type 1 diabetes: the DCCT/EDIC genetics study. Diabetes 2007; 56:2161-8. [PMID: 17513698 DOI: 10.2337/db07-0376] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE We sought to determine if any common variants in the gene for vascular endothelial growth factor (VEGFA) are associated with long-term renal and retinal complications in type 1 diabetes. RESEARCH DESIGN AND METHODS A total of 1,369 Caucasian subjects with type 1 diabetes from the Diabetes Control and Complications Trial (DCCT)/Epidemiology of Diabetes Interventions and Complications (EDIC) Study had an average of 17 retinal photographs and 10 renal measures over 15 years. In the DCCT/EDIC, we studied 18 single nucleotide polymorphisms (SNPs) in VEGFA that represent all linkage disequilibrium bins (pairwise r(2) > or = 0.64) and tested them for association with time to development of severe retinopathy, three or more step progression of retinopathy, clinically significant macular edema, persistent microalbuminuria, and severe nephropathy. RESULTS In a global multi-SNP test, there was a highly significant association of VEGFA SNPs with severe retinopathy (P = 6.8 x 10(-5))-the four other outcomes were all nonsignificant. In survival analyses controlling for covariate risk factors, eight SNPs showed significant association with severe retinopathy (P < 0.05). The most significant single SNP association was rs3025021 (hazard ratio 1.37 [95% CI 1.13-1.66], P = 0.0017). Family-based analyses of severe retinopathy provide evidence of excess transmission of C at rs699947 (P = 0.029), T at rs3025021 (P = 0.013), and the C-T haplotype from both SNPs (P = 0.035). Multi-SNP regression analysis including 15 SNPs, and allowing for pairwise interactions, independently selected 6 significant SNPs (P < 0.05). CONCLUSIONS These data demonstrate that multiple VEGFA variants are associated with the development of severe retinopathy in type 1 diabetes.
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Affiliation(s)
- Hussam Al-Kateb
- Program in Genetics and Genome Biology, Hospital of Sick Children Research Institute, Toronto, ON, Canada
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36
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Allocca M, Tessitore A, Cotugno G, Auricchio A. AAV-mediated gene transfer for retinal diseases. Expert Opin Biol Ther 2007; 6:1279-94. [PMID: 17223737 DOI: 10.1517/14712598.6.12.1279] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Vectors based on the adeno-associated virus (rAAV) are able to transduce the retina of animal models, including non-human primates, for a long-term period, safely and at sustained levels. The ability of the various rAAV serotypes to transduce retinal target cells has been exploited to successfully transfer genes to photoreceptors, retinal pigment epithelium and the inner retina, which are affected in many inherited and non-inherited blinding diseases. rAAV-mediated, constitutive and regulated gene expression at therapeutic levels has been achieved in the retina of animal models, thus providing proof-of-principle of gene therapy efficacy and safety in models of dominant and recessive retinal disorders. In addition, gene transfer of molecules with either neurotrophic or antiangiogenic properties provides useful alternatives to the classic gene replacement for treatment of both mendelian and complex traits affecting the retina. Years of successful rAAV-mediated gene transfer to the retina have resulted in restoration of vision in dogs affected with congenital blindness. This has paved the way to the first attempts at treating inherited retinal diseases in humans with rAAV. Although the results of rAAV clinical trials for non-retinal diseases give a warning that the outcome of viral-mediated gene transfer in humans may be different from that predicted based on results in other species, the immune privilege of the retina combined with the versatility of rAAV serotypes may ultimately provide the first successful treatment of human inherited diseases using rAAV.
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Affiliation(s)
- Mariacarmela Allocca
- Telethon Institute of Genetics and Medicine (TIGEM), Via P. Castellino, 111. 80131 Napoli, Italy.
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Kilic Ü, Kilic E, Järve A, Guo Z, Spudich A, Bieber K, Barzena U, Bassetti CL, Marti HH, Hermann DM. Human vascular endothelial growth factor protects axotomized retinal ganglion cells in vivo by activating ERK-1/2 and Akt pathways. J Neurosci 2006; 26:12439-46. [PMID: 17135405 PMCID: PMC6674905 DOI: 10.1523/jneurosci.0434-06.2006] [Citation(s) in RCA: 145] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Based on its trophic effects on neurons and vascular cells, vascular endothelial growth factor (VEGF) is a promising candidate for the treatment of neurodegenerative diseases. To evaluate the therapeutic potential of VEGF, we here examined effects of this growth factor on the degeneration of axotomized retinal ganglion cells (RGCs), which, as CNS-derived neurons, offer themselves in an excellent way to study neuroprotection in vivo. Making use of a transgenic mouse line that constitutively expresses human VEGF under a neuron-specific enolase promoter, we show that (1) the VEGF-transgenic retina overexpresses human VEGF, (2) RGCs carry the VEGF receptor-2, and (3) vascular networks in normal and axotomized VEGF-transgenic (tg) retinas do not differ from control animals. After axotomy, RGCs of VEGF-tg mice were protected against delayed degeneration, as compared with wild-type littermates. Western blots revealed increased phosphorylated ERK-1/2 and Akt and reduced phosphorylated p38 and activated caspase-3 levels in axotomized VEGF-transgenic retinas. Intravitreous injections of pharmacological ERK-1/2 (PD98059) or Akt (LY294002) inhibitors showed that VEGF exerts neuroprotection by dual activation of ERK-1/2 and Akt pathways. In view that axotomy-induced RGC death occurs slowly and considering that RGCs are CNS-derived neurons, we predict the clinical implementation of VEGF in neurodegenerative diseases of both brain and retina.
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Affiliation(s)
- Ülkan Kilic
- Department of Neurology, University Hospital Zurich, CH-8091 Zurich, Switzerland, and
| | - Ertugrul Kilic
- Department of Neurology, University Hospital Zurich, CH-8091 Zurich, Switzerland, and
| | - Anne Järve
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Zeyun Guo
- Department of Neurology, University Hospital Zurich, CH-8091 Zurich, Switzerland, and
| | - Annett Spudich
- Department of Neurology, University Hospital Zurich, CH-8091 Zurich, Switzerland, and
| | - Katja Bieber
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Uxue Barzena
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Claudio L. Bassetti
- Department of Neurology, University Hospital Zurich, CH-8091 Zurich, Switzerland, and
| | - Hugo H. Marti
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Dirk M. Hermann
- Department of Neurology, University Hospital Zurich, CH-8091 Zurich, Switzerland, and
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Gaucher D, Chiappore JA, Pâques M, Simonutti M, Boitard C, Sahel JA, Massin P, Picaud S. Microglial changes occur without neural cell death in diabetic retinopathy. Vision Res 2006; 47:612-23. [PMID: 17267004 DOI: 10.1016/j.visres.2006.11.017] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Revised: 07/29/2006] [Accepted: 11/08/2006] [Indexed: 11/28/2022]
Abstract
Very early neuroglial changes have been observed to precede major vascular changes in the retina of diabetic patients and animal models. We investigated the sequence of these neuroglial changes further, in mice with alloxan-induced diabetes. Diabetes was induced by a single injection of Alloxan into C57/Bl6 mice, which subsequently received daily insulin injections. Diabetic and control animals were weighed and their blood glucose levels were determined weekly. Electroretinographic recordings and scanner laser ophthalmoscope (SLO) examinations were carried out 15 days, one month and three months after the onset of diabetes. Diabetes induction was confirmed by the presence of glucose in the urine, a tripling of blood glucose level, weight loss and an increase in glycated haemoglobin levels. Three months after diabetes onset, the electroretinogram b/a wave amplitude ratio was decreased at the highest light intensities and oscillatory potentials were delayed. The retinal fundus and vessels remained unchanged. No cell apoptosis was detected in vertical and horizontal sections of the retina by TUNEL or immunocytochemistry for the active caspase 3. No increase in GFAP-immunostaining indicative of a glial reaction was observed in Müller glial cells. By contrast, changes in the morphology of microglial cells were observed, with marked shortening of the dendrites. Thus, the microglial reaction occurs very early in progression to diabetic retinopathy, at about the same time as early electroretinographic modifications. The absence of apoptotic cells, contrasting with previous results in mice with streptozotocin-induced diabetes, is consistent with insulin neuroprotection.
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Affiliation(s)
- David Gaucher
- INSERM U-592, Hôpital St. Antoine, Laboratoire de Physiopathologie Cellulaire et Moléculaire de la Rétine, Bâtiment Kourilsky, and Université Pierre et Marie Curie Paris-6, Paris, France
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39
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Shen WY, Lai CM, Graham CE, Binz N, Lai YKY, Eade J, Guidolin D, Ribatti D, Dunlop SA, Rakoczy PE. Long-term global retinal microvascular changes in a transgenic vascular endothelial growth factor mouse model. Diabetologia 2006; 49:1690-701. [PMID: 16752188 DOI: 10.1007/s00125-006-0274-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2005] [Accepted: 03/20/2006] [Indexed: 01/29/2023]
Abstract
AIMS/HYPOTHESIS Vascular endothelial growth factor (VEGF) plays a pivotal role in the pathogenesis of diabetic retinopathy. We investigated whether transgenic mice with moderate VEGF expression in photoreceptors (trVEGF029) developed changes similar to diabetic retinopathy and whether retinopathy progressed with time. MATERIALS AND METHODS Human VEGF(165) (hVEGF(165)) expression was analysed using ELISA and quantitative RT-PCR; serum glucose levels were also measured. Fundus fluorescein angiography (FA) was used to screen the degree of retinopathy from 6 weeks. Dynamic changes in the density of retinal microvasculature, as well as other changes similar to diabetic retinopathy, including retinal leucostasis, capillary endothelial cell and pericyte loss, and numbers of acellular capillaries, were quantified. RESULTS trVEGF029 mice were normoglycaemic and showed a moderate, short-term hVEGF(165) upregulation for up to 3 weeks. Changes in the retinal microvasculature not only mimicked those seen in diabetic retinopathy, but also showed similar pathological progression with time. FA at 6 weeks identified two phenotypes, mild and moderate, which were distinguished by the extent of vascular leakage. Quantitative analysis of diabetic retinopathy-like changes revealed that these parameters were tightly correlated with the initial degree of vascular leakage; low levels reflected slow and limited retinal microvascular changes in mild cases and high levels reflected more rapid and extensive changes in moderate cases. CONCLUSIONS/INTERPRETATION The data suggest that even an early short-term elevation in hVEGF(165) expression might set a train of events that lead to progressive retinopathy. Induction of many features characteristic of diabetic retinopathy in trVEGF029 enables mechanisms leading to the disease state to be examined, and provides a relevant animal model for testing novel therapeutics.
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Affiliation(s)
- W-Y Shen
- Centre of Ophthalmology and Visual Science, The University of Western Australia, Nedlands, Perth, WA, Australia
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Lai CM, Shen WY, Brankov M, Lai YKY, Barnett NL, Lee SY, Yeo IYS, Mathur R, Ho JES, Pineda P, Barathi A, Ang CL, Constable IJ, Rakoczy EP. Long-term Evaluation of AAV-Mediated sFlt-1 Gene Therapy for Ocular Neovascularization in Mice and Monkeys. Mol Ther 2005; 12:659-68. [PMID: 16023893 DOI: 10.1016/j.ymthe.2005.04.022] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2005] [Revised: 04/18/2005] [Accepted: 04/28/2005] [Indexed: 10/25/2022] Open
Abstract
Vascular endothelial growth factor (VEGF) is one of the major mediators of retinal ischemia-associated neovascularization. We have shown here that adeno-associated virus (AAV)-mediated expression of sFlt-1, a soluble form of the Flt-1 VEGF receptor, was maintained for up to 8 and 17 months postinjection in mice and in monkeys, respectively. The expression of sFlt-1 was associated with the long-term (8 months) regression of neovascular vessels in 85% of trVEGF029 eyes. In addition, it resulted in the maintenance of retinal morphology, as the majority of the treated trVEGF029 eyes (75%) retained high numbers of photoreceptors, and in retinal function as measured by electroretinography. AAV-mediated expression of sFlt-1 prevented the development of laser photocoagulation-induced choroidal neovascularization in all treated monkey eyes. There were no clinically or histologically detectable signs of toxicity present in either animal model following AAV.sFlt injection. These results suggest that AAV-mediated secretion gene therapy could be considered for treatment of retinal and choroidal neovascularizations.
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Affiliation(s)
- Chooi-May Lai
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, Australia.
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