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Xu X, Han N, Zhao F, Fan R, Guo Q, Han X, Liu Y, Luo G. Inefficacy of anti-VEGF therapy reflected in VEGF-mediated photoreceptor degeneration. MOLECULAR THERAPY. NUCLEIC ACIDS 2024; 35:102176. [PMID: 38689803 PMCID: PMC11059333 DOI: 10.1016/j.omtn.2024.102176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 03/19/2024] [Indexed: 05/02/2024]
Abstract
Retinal neovascularization (RNV) is primarily driven by vascular endothelial growth factor (VEGF). However, current anti-VEGF therapies are limited by short half-lives and repeated injections, which reduce patient quality of life and increase medical risks. Additionally, not all patients benefit from anti-VEGF monotherapy, and some problems, such as unsatisfactory vision recovery, persist after long-term treatment. In this study, we constructed a recombinant adeno-associated virus (AAV), AAV2-SPLTH, which encodes an anti-VEGF antibody similar to bevacizumab, and assessed its effects in a doxycycline-induced Tet-opsin-VEGFA mouse model of RNV. AAV2-SPLTH effectively inhibited retinal leakage, RNV progression, and photoreceptor apoptosis in a Tet-opsin-VEGF mouse model. However, proteomic sequencing showed that AAV2-SPLTH failed to rescue the expression of phototransduction-related genes, which corresponded to reduced photoreceptor cell numbers. This study suggests that anti-VEGF monotherapy can significantly inhibit RNV to some extent but may not be enough to save visual function in the long term.
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Affiliation(s)
- Xin Xu
- Institute of Health Sciences, China Medical University, Shenyang 110122, China
| | - Ni Han
- Institute of Health Sciences, China Medical University, Shenyang 110122, China
| | - Fangkun Zhao
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang 110005, China
| | - Ruoyue Fan
- Bionce Biotechnology, Co., Ltd, Nanjing 210061, China
| | - Qingguo Guo
- Institute of Health Sciences, China Medical University, Shenyang 110122, China
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang 110122, China
| | - Xuefei Han
- Bionce Biotechnology, Co., Ltd, Nanjing 210061, China
| | - Ying Liu
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang 110122, China
| | - Guangzuo Luo
- Institute of Health Sciences, China Medical University, Shenyang 110122, China
- Bionce Biotechnology, Co., Ltd, Nanjing 210061, China
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2
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Han N, Xu X, Liu Y, Luo G. AAV2-antiVEGFscFv gene therapy for retinal neovascularization. Mol Ther Methods Clin Dev 2023; 31:101145. [PMID: 38027065 PMCID: PMC10679950 DOI: 10.1016/j.omtm.2023.101145] [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: 04/19/2023] [Accepted: 10/25/2023] [Indexed: 12/01/2023]
Abstract
Retinal neovascularization (NV) may lead to irreversible vision impairment, the main treatment for which is the inhibition of vascular endothelial growth factor (VEGF). Existing drugs show limited clinical benefits because of their high prices and short half-lives, which increase the financial burden and medical risks to patients. Gene therapy on the basis of adeno-associated viruses is a promising approach to overcome these limitations because of the nonintegrative nature, low immunogenicity, and potential long-term gene expression of adeno-associated viruses. In this study, we constructed a novel recombinant adeno-associated virus with the single-chain fragment variable (scFv) fragment of the anti-VEGF antibody, AAV2-antiVEGFscFv, consisting of the VH and VL structural domains of IgG. AAV2-antiVEGFscFv effectively inhibited NV, retinal leakage, and retinal detachment in oxygen-induced retinopathy (OIR) mice, Tet/opsin/VEGF double-transgenic mice, and VEGF-induced rabbit NV models. AAV2-antiVEGFscFv also significantly suppressed VEGF-induced inflammation. Furthermore, we showed that AAV2-antiVEGFscFv could be sustainably expressed for a prolonged period and exhibited low immunotoxicity in vivo. This study indicates that AAV2-antiVEGFscFv could be a potential approach for NV treatment and provides strong support for preclinical research.
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Affiliation(s)
- Ni Han
- Institute of Health Sciences, China Medical University, Shenyang 110122, China
| | - Xin Xu
- Institute of Health Sciences, China Medical University, Shenyang 110122, China
| | - Ying Liu
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang 110122, China
| | - Guangzuo Luo
- Institute of Health Sciences, China Medical University, Shenyang 110122, China
- Bionce Biotechnology, Ltd., Nanjing 210061, China
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3
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Zhang XJ, Chen XN, Tang FY, Szeto S, Ling XT, Lin ZX, Tham CC, Pang CP, Chen LJ, Yam JC. Pathogenesis of myopic choroidal neovascularization: A systematic review and meta-analysis. Surv Ophthalmol 2023; 68:1011-1026. [PMID: 37517683 DOI: 10.1016/j.survophthal.2023.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 07/19/2023] [Accepted: 07/24/2023] [Indexed: 08/01/2023]
Abstract
Myopic choroidal neovascularization (CNV) is a vision-threatening complication of high myopia. Here, we systematically review cohort, case-control, and cross-sectional studies in PubMed, Embase, and Web of Science, and summarize the associated factors of myopic CNV using meta-analysis where applicable. Among 1,333 records assessed, 50 were found eligible, all having a low-to-moderate risk of bias. Highly myopic eyes with CNV had a higher risk of lacquer cracks (odds ratio = 2.88) and patchy chorioretinal atrophy (odds ratio = 3.43) than those without. The mean posterior staphyloma height (µm) was greater in myopic CNV eyes than in highly myopic eyes without CNV (mean difference = 82.03). The thinning of choroidal thickness (µm) between myopic eyes with and without CNV differed significantly (mean difference = -47.76). The level of vascular endothelial growth factor (pg/ml) in the aqueous humor of myopic CNV eyes was significantly higher than in highly myopic eyes without CNV (mean difference = 24.98), the same as interleukin-8 (IL-8) (pg/ml, mean difference = 7.73). Single-nucleotide polymorphisms in the vascular endothelial growth factor, complement factor I, and collagen type VIII alpha 1 genes were associated with myopic CNV. We found that myopic CNV eyes have a higher ratio of lacquer cracks and patchy chorioretinal atrophy, thinner choroid, greater posterior staphyloma height, and a higher level of vascular endothelial growth factor and IL-8 in aqueous. Structural predisposing lesions, hemodynamic, genetic, and systemic factors are also associated with myopic CNV.
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Affiliation(s)
- Xiu Juan Zhang
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong; Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, China
| | - Xiu Nian Chen
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong
| | - Fang Yao Tang
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong
| | - Simon Szeto
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong; Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Hong Kong
| | - Xiang Tian Ling
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong
| | - Zi Xuan Lin
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong
| | - Clement C Tham
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong; Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, China; Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Hong Kong; Hong Kong Eye Hospital, Hong Kong; Hong Kong Hub of Paediatric Excellence, The Chinese University of Hong Kong, Hong Kong; Department of Ophthalmology, Hong Kong Children's Hospital, Hong Kong
| | - Chi Pui Pang
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong; Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, China; Hong Kong Hub of Paediatric Excellence, The Chinese University of Hong Kong, Hong Kong
| | - Li Jia Chen
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong; Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, China; Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Hong Kong; Hong Kong Hub of Paediatric Excellence, The Chinese University of Hong Kong, Hong Kong.
| | - Jason C Yam
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong; Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, China; Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Hong Kong; Hong Kong Eye Hospital, Hong Kong; Hong Kong Hub of Paediatric Excellence, The Chinese University of Hong Kong, Hong Kong; Department of Ophthalmology, Hong Kong Children's Hospital, Hong Kong.
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4
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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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5
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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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6
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Qin Y, Dinabandhu A, Cao X, Sanchez JC, Jee K, Rodrigues M, Guo C, Zhang J, Vancel J, Menon D, Khan NS, Ma T, Tzeng SY, Daoud Y, Green JJ, Semenza GL, Montaner S, Sodhi A. ANGPTL4 influences the therapeutic response of patients with neovascular age-related macular degeneration by promoting choroidal neovascularization. JCI Insight 2022; 7:e157896. [PMID: 35653189 PMCID: PMC9310537 DOI: 10.1172/jci.insight.157896] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 05/18/2022] [Indexed: 01/14/2023] Open
Abstract
Most patients with neovascular age-related macular degeneration (nvAMD), the leading cause of severe vision loss in elderly US citizens, respond inadequately to current therapies targeting a single angiogenic mediator, vascular endothelial growth factor (VEGF). Here, we report that aqueous fluid levels of a second vasoactive mediator, angiopoietin-like 4 (ANGPTL4), can help predict the response of patients with nvAMD to anti-VEGF therapies. ANGPTL4 expression was higher in patients who required monthly treatment with anti-VEGF therapies compared with patients who could be effectively treated with less-frequent injections. We further demonstrate that ANGPTL4 acts synergistically with VEGF to promote the growth and leakage of choroidal neovascular (CNV) lesions in mice. Targeting ANGPTL4 expression was as effective as targeting VEGF expression for treating CNV in mice, while simultaneously targeting both was more effective than targeting either factor alone. To help translate these findings to patients, we used a soluble receptor that binds to both VEGF and ANGPTL4 and effectively inhibited the development of CNV lesions in mice. Our findings provide an assay that can help predict the response of patients with nvAMD to anti-VEGF monotherapy and suggest that therapies targeting both ANGPTL4 and VEGF will be a more effective approach for the treatment of this blinding disease.
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Affiliation(s)
- Yu Qin
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Ophthalmology, the Fourth Affiliated Hospital of China Medical University, Eye Hospital of China Medical University, Key Lens Research Laboratory of Liaoning Province, Shenyang, China
| | - Aumreetam Dinabandhu
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Oncology and Diagnostic Sciences, School of Dentistry, Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, Maryland, USA
| | - Xuan Cao
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jaron Castillo Sanchez
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kathleen Jee
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Murilo Rodrigues
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Chuanyu Guo
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jing Zhang
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- State Key Laboratory of Ophthalmology, Clinical Research Center, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Jordan Vancel
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Deepak Menon
- Department of Oncology and Diagnostic Sciences, School of Dentistry, Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, Maryland, USA
| | - Noore-Sabah Khan
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Tao Ma
- Department of Oncology and Diagnostic Sciences, School of Dentistry, Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, Maryland, USA
| | - Stephany Y. Tzeng
- Department of Biomedical Engineering, Institute for NanoBioTechnology, and
- Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Yassine Daoud
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jordan J. Green
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Biomedical Engineering, Institute for NanoBioTechnology, and
- Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Gregg L. Semenza
- Department of Genetic Medicine
- Department of Pediatrics
- Department of Medicine
- Department of Oncology
- Department of Radiation Oncology, and
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Silvia Montaner
- Department of Oncology and Diagnostic Sciences, School of Dentistry, Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, Maryland, USA
| | - Akrit Sodhi
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Xia YF, Wei J. Study on Factors Associated with High Myopia CNV in Aqueous Humor and Serum. BIOMED RESEARCH INTERNATIONAL 2022; 2022:8592729. [PMID: 35535041 PMCID: PMC9078789 DOI: 10.1155/2022/8592729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 03/16/2022] [Accepted: 04/02/2022] [Indexed: 11/30/2022]
Abstract
Objective The objective is to investigate the relationship and correlation between PEDF and TGF-β in aqueous humor and serum and high myopia CNV lesions. Methods For each group of patients (namely, group A: patients with high myopia CNV (mCNV); group B: patients with high myopia without CNV; group C: patients with CNV caused by other eye diseases; and group D (control group): patients with simple cataract (without CNV and high myopia)), 20 patients were collected. A total of 40 patients have been collected since the beginning of the study in December 2020, including 7 patients in group A, 13 patients in group B, 10 patients in group C, and 10 patients in group D. Serum and aqueous humor samples were collected, and PEDF and TGF-β levels in serum and aqueous humor were detected by enzyme-linked immunosorbent assay (ELISA). SPSS 26.0 statistical software was used to process the data. Independent sample t-test was used to compare the data of the same factor in the same group between serum and aqueous humor. Comparisons of the same factors between different groups were performed using a one-way analysis of variance (ANOVA). Correlation analysis was conducted by the Pearson correlation coefficient test. P < 0.05 indicated that the difference was statistically significant. Results There were no significant differences in age, gender, and course of disease among all groups (P > 0.05). The concentration of PEDF in aqueous humor in group A and group C was higher than that in group B and group D. There was no significant correlation between serum PEDF content and the above-mentioned diseases. The concentration of TGF-β in aqueous humor in groups A, B, and C was significantly higher than that in group D. However, there was no significant correlation between TGF-β content in serum and the above-mentioned diseases. There was no significant correlation between aqueous humor and serum PEDF. There was no significant correlation between the content of TGF-β in aqueous humor and serum. Conclusion TGF-β in aqueous humor may be involved in the development of high myopia and intraocular CNV disease. However, PEDF in aqueous humor may be involved in the development of intraocular CNV disease and has no significant correlation with high myopia. At the same time, TGF-β and PEDF in serum had no significant correlation with high myopia and intraocular CNV disease. There was no significant correlation between the concentrations of TGF-β and PEDF in aqueous humor and serum.
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Affiliation(s)
- Yi Fan Xia
- Henan University of Science and Technology, Luoyang, Henan Province 471000, China
| | - Jing Wei
- Henan University of Science and Technology, Luoyang, Henan Province 471000, China
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Campochiaro PA. Retinal and Choroidal Vascular Diseases: Past, Present, and Future: The 2021 Proctor Lecture. Invest Ophthalmol Vis Sci 2021; 62:26. [PMID: 34817536 PMCID: PMC8637787 DOI: 10.1167/iovs.62.14.26] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Peter A Campochiaro
- Departments of Ophthalmology and Neuroscience, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
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9
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Qiang W, Wei R, Chen Y, Chen D. Clinical Pathological Features and Current Animal Models of Type 3 Macular Neovascularization. Front Neurosci 2021; 15:734860. [PMID: 34512255 PMCID: PMC8427186 DOI: 10.3389/fnins.2021.734860] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 07/29/2021] [Indexed: 02/05/2023] Open
Abstract
Type 3 macular neovascularization (MNV3), or retinal angiomatous proliferation (RAP), is a distinct type of neovascular age-related macular degeneration (AMD), which is a leading cause of vision loss in older persons. During the past decade, systematic investigation into the clinical, multimodal imaging, and histopathological features and therapeutic outcomes has provided important new insight into this disease. These studies favor the retinal origin of MNV3 and suggest the involvement of retinal hypoxia, inflammation, von Hippel–Lindau (VHL)–hypoxia-inducible factor (HIF)–vascular endothelial growth factor (VEGF) pathway, and multiple cell types in the development and progression of MNV3. Several mouse models, including the recently built Rb/p107/Vhl triple knockout mouse model by our group, have induced many of the histological features of MNV3 and provided much insight into the underlying pathological mechanisms. These models have revealed the roles of retinal hypoxia, inflammation, lipid metabolism, VHL/HIF pathway, and retinoblastoma tumor suppressor (Rb)–E2F cell cycle pathway in the development of MNV3. This article will summarize the clinical, multimodal imaging, and pathological features of MNV3 and the diversity of animal models that exist for MNV3, as well as their strengths and limitations.
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Affiliation(s)
- Wei Qiang
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Ran Wei
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Yongjiang Chen
- The School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - Danian Chen
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
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10
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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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11
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Hu J, Zhu M, Li D, Wu Q, Le YZ. VEGF as a Direct Functional Regulator of Photoreceptors and Contributing Factor to Diabetes-Induced Alteration of Photoreceptor Function. Biomolecules 2021; 11:biom11070988. [PMID: 34356612 PMCID: PMC8301820 DOI: 10.3390/biom11070988] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/02/2021] [Accepted: 07/03/2021] [Indexed: 12/15/2022] Open
Abstract
Vascular endothelial growth factor (VEGF) is a major therapeutic target for blood-retina barrier (BRB) breakdown in diabetic retinopathy (DR), age-related macular degeneration (AMD), and other hypoxic retinal vascular disorders. To determine whether VEGF is a direct regulator of retinal neuronal function and its potential role in altering vision during the progression of DR, we examined the immediate impact of recombinant VEGF (rVEGF) on photoreceptor function with electroretinography in C57BL6 background wild-type (WT) and Akita spontaneous diabetic mice. Shortly after intravitreal injections, rVEGF caused a significant reduction of scotopic ERG a-wave and b-wave amplitudes and photopic ERG b-wave amplitudes in a dose-dependent manner in dark-adapted 1.5-mo-old WT mice. Compared with WT controls, 5-mo-old Akita spontaneous diabetic mice demonstrated a significant reduction in scotopic ERG a-wave and b-wave amplitudes and photopic ERG b-wave amplitudes. However, the effect of rVEGF altered photoreceptor function in WT controls was diminished in 5-mo-old Akita spontaneous diabetic mice. In conclusion, our results suggest that VEGF is a direct functional regulator of photoreceptors and VEGF up-regulation in DR is a contributing factor to diabetes-induced alteration of photoreceptor function. This information is critical to the understanding of the therapeutic effect and to the care of anti-VEGF drug-treated patients for BRB breakdown in DR, AMD, and other hypoxic retinal vascular disorders.
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Affiliation(s)
- Jianyan Hu
- Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.H.); (M.Z.); (D.L.)
- Department of Ophthalmology, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai 200233, China
| | - Meili Zhu
- Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.H.); (M.Z.); (D.L.)
| | - Dai Li
- Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.H.); (M.Z.); (D.L.)
- School of Optometry, Hubei University of Science and Technology, Xianning 437100, China
| | - Qiang Wu
- Department of Ophthalmology, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai 200233, China
- Shanghai Key Laboratory of Diabetes Mellitus, Shanghai 200233, China
- Correspondence: (Q.W.); (Y.-Z.L.)
| | - Yun-Zheng Le
- Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (J.H.); (M.Z.); (D.L.)
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Correspondence: (Q.W.); (Y.-Z.L.)
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12
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Becker K, Klein H, Simon E, Viollet C, Haslinger C, Leparc G, Schultheis C, Chong V, Kuehn MH, Fernandez-Albert F, Bakker RA. In-depth transcriptomic analysis of human retina reveals molecular mechanisms underlying diabetic retinopathy. Sci Rep 2021; 11:10494. [PMID: 34006945 PMCID: PMC8131353 DOI: 10.1038/s41598-021-88698-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 04/15/2021] [Indexed: 02/03/2023] Open
Abstract
Diabetic Retinopathy (DR) is among the major global causes for vision loss. With the rise in diabetes prevalence, an increase in DR incidence is expected. Current understanding of both the molecular etiology and pathways involved in the initiation and progression of DR is limited. Via RNA-Sequencing, we analyzed mRNA and miRNA expression profiles of 80 human post-mortem retinal samples from 43 patients diagnosed with various stages of DR. We found differentially expressed transcripts to be predominantly associated with late stage DR and pathways such as hippo and gap junction signaling. A multivariate regression model identified transcripts with progressive changes throughout disease stages, which in turn displayed significant overlap with sphingolipid and cGMP-PKG signaling. Combined analysis of miRNA and mRNA expression further uncovered disease-relevant miRNA/mRNA associations as potential mechanisms of post-transcriptional regulation. Finally, integrating human retinal single cell RNA-Sequencing data revealed a continuous loss of retinal ganglion cells, and Müller cell mediated changes in histidine and β-alanine signaling. While previously considered primarily a vascular disease, attention in DR has shifted to additional mechanisms and cell-types. Our findings offer an unprecedented and unbiased insight into molecular pathways and cell-specific changes in the development of DR, and provide potential avenues for future therapeutic intervention.
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Affiliation(s)
- Kolja Becker
- Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Holger Klein
- Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Eric Simon
- Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Coralie Viollet
- Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Christian Haslinger
- Global Computational Biology & Digital Sciences, Boehringer Ingelheim RCV GmbH & Co. KG, Vienna, Austria
| | - German Leparc
- Translational Medicine & Clinical Pharmacology, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Christian Schultheis
- Translational Medicine & Clinical Pharmacology, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany
| | - Victor Chong
- Therapeutic Area CNS Retinopathies Emerging Areas, BI International GmbH, Ingelheim, Germany
| | - Markus H Kuehn
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
- Department of Veterans Affairs, Center for the Prevention and Treatment of Visual Loss, Iowa City, IA, 52246, USA
| | - Francesc Fernandez-Albert
- Global Computational Biology & Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany.
| | - Remko A Bakker
- Global Department Cardio-Metabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany.
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13
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Saunders DC, Aamodt KI, Richardson TM, Hopkirk AJ, Aramandla R, Poffenberger G, Jenkins R, Flaherty DK, Prasad N, Levy SE, Powers AC, Brissova M. Coordinated interactions between endothelial cells and macrophages in the islet microenvironment promote β cell regeneration. NPJ Regen Med 2021; 6:22. [PMID: 33824346 PMCID: PMC8024255 DOI: 10.1038/s41536-021-00129-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 02/24/2021] [Indexed: 12/14/2022] Open
Abstract
Endogenous β cell regeneration could alleviate diabetes, but proliferative stimuli within the islet microenvironment are incompletely understood. We previously found that β cell recovery following hypervascularization-induced β cell loss involves interactions with endothelial cells (ECs) and macrophages (MΦs). Here we show that proliferative ECs modulate MΦ infiltration and phenotype during β cell loss, and recruited MΦs are essential for β cell recovery. Furthermore, VEGFR2 inactivation in quiescent ECs accelerates islet vascular regression during β cell recovery and leads to increased β cell proliferation without changes in MΦ phenotype or number. Transcriptome analysis of β cells, ECs, and MΦs reveals that β cell proliferation coincides with elevated expression of extracellular matrix remodeling molecules and growth factors likely driving activation of proliferative signaling pathways in β cells. Collectively, these findings suggest a new β cell regeneration paradigm whereby coordinated interactions between intra-islet MΦs, ECs, and extracellular matrix mediate β cell self-renewal.
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Affiliation(s)
- Diane C Saunders
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
- Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kristie I Aamodt
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Tiffany M Richardson
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Alexander J Hopkirk
- Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Radhika Aramandla
- Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Greg Poffenberger
- Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Regina Jenkins
- Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA
| | - David K Flaherty
- Flow Cytometry Shared Resource, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Nripesh Prasad
- Hudson Alpha Institute of Biotechnology, Huntsville, AL, USA
| | - Shawn E Levy
- Hudson Alpha Institute of Biotechnology, Huntsville, AL, USA
| | - Alvin C Powers
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA.
- Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA.
- VA Tennessee Valley Healthcare, Nashville, TN, USA.
| | - Marcela Brissova
- Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA.
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14
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Liu S, Biesemeier AK, Tschulakow AV, Thakkar HV, Julien-Schraermeyer S, Schraermeyer U. A new rat model of treatment-naive quiescent choroidal neovascularization induced by human VEGF165 overexpression. Biol Open 2020; 9:bio048736. [PMID: 32086250 PMCID: PMC7295592 DOI: 10.1242/bio.048736] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/07/2020] [Indexed: 12/29/2022] Open
Abstract
Vascular endothelial growth factor (VEGF) is a crucial stimulator for choroidal neovascularization (CNV). Our aim was to develop a reproducible and valid treatment-naive quiescent CNV (i.e. without signs of exudation and with normal visual acuity) rat model by subretinal injection of an adeno-associated virus (AAV)-VEGFA165 vector. The CNV development was longitudinally followed up in vivo by scanning laser ophthalmoscopy/optical coherence tomography, fluorescein and Indocyanine Green angiographies and ex vivo by electron microscopy (EM) and immunohistochemistry. In total, 57 eyes were analysed. In vivo, a quiescent CNV was observed in 93% of the eyes 6 weeks post-transduction. In EM, CNV vessels with few fenestrations, multi-layered basement membranes and bifurcation of endothelial cells were observed sharing the human CNV features. Human VEGF overexpression, multi-layered retinal pigment epithelium (RPE) (RPE65) and macrophages/activated microglia (Iba1) were also detected. In addition, 19 CNV eyes were treated for up to 3 weeks with bevacizumab. The retinal and CNV lesion thickness decreased significantly in bevacizumab-treated CNV eyes compared with untreated CNV eyes 1 week after the treatment. In conclusion, our experimental CNV resembles those seen in patients suffering from treatment-naive quiescent CNV in wet age-related macular degeneration (AMD), and responds to short-term treatment with bevacizumab. Our new model can, therefore, be used to test the long-term effect of new drugs targeting CNV under precisely-defined conditions.
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Affiliation(s)
- Shan Liu
- Center for Ophthalmology, Division of Experimental Vitreoretinal Surgery, Tübingen 72076, Germany
| | - Antje K Biesemeier
- Center for Ophthalmology, Division of Experimental Vitreoretinal Surgery, Tübingen 72076, Germany
- Natural and Medical Institute at the University of Tübingen, Applied Material Science and Electron Microscopy, Reutlingen 72770, Germany
| | - Alexander V Tschulakow
- Center for Ophthalmology, Division of Experimental Vitreoretinal Surgery, Tübingen 72076, Germany
- STZ OcuTox Preclinical Drug Assessment, Hechingen 72379, Germany
| | - Harsh V Thakkar
- Center for Ophthalmology, Division of Experimental Vitreoretinal Surgery, Tübingen 72076, Germany
- STZ OcuTox Preclinical Drug Assessment, Hechingen 72379, Germany
| | - Sylvie Julien-Schraermeyer
- Center for Ophthalmology, Division of Experimental Vitreoretinal Surgery, Tübingen 72076, Germany
- STZ OcuTox Preclinical Drug Assessment, Hechingen 72379, Germany
| | - Ulrich Schraermeyer
- Center for Ophthalmology, Division of Experimental Vitreoretinal Surgery, Tübingen 72076, Germany
- STZ OcuTox Preclinical Drug Assessment, Hechingen 72379, Germany
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15
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Edatt L, Poyyakkara A, Raji GR, Ramachandran V, Shankar SS, Kumar VBS. Role of Sirtuins in Tumor Angiogenesis. Front Oncol 2020; 9:1516. [PMID: 32010617 PMCID: PMC6978795 DOI: 10.3389/fonc.2019.01516] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 12/16/2019] [Indexed: 12/11/2022] Open
Abstract
Generally, changes in the metabolic status of cells under conditions like hypoxia and accumulation of lactate can be sensed by various sensing mechanisms, leading to modulation of a number of signal transduction pathways and transcription factors. Several of the proangiogenic cytokines like VEGF, FGF, PDGF, TGF-β, Ang-2, ILs, etc. are secreted by cancer cells, under hypoxic microenvironment. These cytokines bind to their receptors on the endothelial cells and activates a number of signaling pathways including Akt/PIP3, Src, p38/MAPK, Smad2/3, etc., which ultimately results in the proliferation and migration of endothelial cells. Transcription factors that are activated in response to the metabolic status of tumors include HIFs, NF-κb, p53, El-2, and FOXO. Many of these transcription factors has been reported to be regulated by a class of histone deacetylase called sirtuins. Sirtuins are NAD+ dependent histone deacetylases that play pivotal role in the regulation of tumor cell metabolism, proliferation, migration and angiogenesis. The major function of sirtuins include, deacetylation of histones as well as some non-histone proteins like NF-κB, FOXOs, PPAR⋎, PGC1-α, enzymes like acetyl coenzymeA and structural proteins like α tubulin. In the cell, sirtuins are generally considered as the redox sensors and their activities are dependent on the metabolic status of the cell. Understanding the intricate regulatory mechanisms adopted by sirtuins, is crucial in devising effective therapeutic strategies against angiogenesis, metastasis and tumor progression. Keeping this in mind, the present review focuses on the role of sirtuins in the process of tumor angiogenesis and the regulatory mechanisms employed by them.
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Affiliation(s)
| | | | | | | | | | - V. B. Sameer Kumar
- Department of Biochemistry and Molecular Biology, Central University of Kerala, Kasaragod, India
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16
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Anisotropic poly(lactic-co-glycolic acid) microparticles enable sustained release of a peptide for long-term inhibition of ocular neovascularization. Acta Biomater 2019; 97:451-460. [PMID: 31374338 DOI: 10.1016/j.actbio.2019.07.054] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 06/21/2019] [Accepted: 07/29/2019] [Indexed: 12/11/2022]
Abstract
Leading causes of vision loss include neovascular age-related macular degeneration (NVAMD) and macular edema (ME), which both require frequent intravitreal injections for treatment. A safe, poly(lactic-co-glycolic acid) (PLGA)-based biodegradable polymeric microparticle (MP) delivery system was developed that encapsulates and protects a biomimetic peptide from degradation, allows sustained intraocular release through polymer hydrolysis, and demonstrates a prolonged anti-angiogenic effect in vivo in three different NVAMD animal models (a laser-induced choroidal neovascularization mouse model, a rhoVEGF transgenic mouse model, and a Tet/opsin/VEGF transgenic mouse model) following intravitreal administration. The role of copolymer composition and microparticle shape was explored and 85:15 lactide-to-glycolide PLGA formed into ellipsoidal microparticles was found to be effective at inhibiting neovascularization for at least 16 weeks in vivo. Treatments were found to not only inhibit the growth of neovascularization, but also to cause regression of the neovasculature, reduce vascular leakage, and prevent exudative retinal detachment. These particulate devices are promising for the sustained release of biologics in the eye and may be useful for treating retinal diseases. STATEMENT OF SIGNIFICANCE: Devastating retinal diseases cause blindness in millions of people around the world. Current protein-based treatments have insufficient efficacy for many patients and also necessitate frequent intravitreal injections. Here, we demonstrate a new treatment consisting of a peptide encapsulated in biodegradable microparticles. We explore the effects of copolymer composition and physical shape of polymeric microparticles and find that both modulate peptide release. Efficacy of the treatment was validated in three different mouse models and the lead formulation was determined to be effective long-term, for at least 16 weeks in vivo, following a single injection. Treatments inhibited and regressed neovascularization as well as reduced vascular leakage. Anisotropic polymeric microparticles are promising for the sustained release of biologics in the eye.
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17
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Small Molecule-Based Inducible Gene Therapies for Retinal Degeneration. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1185:65-69. [PMID: 31884590 DOI: 10.1007/978-3-030-27378-1_11] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The eye is an excellent target organ for gene therapy. It is physically isolated, easily accessible, immune-privileged, and postmitotic. Furthermore, potential gene therapies introduced into the eye can be evaluated by noninvasive methods such as fundoscopy, electroretinography, and optical coherence tomography. In the last two decades, great advances have been made in understanding the molecular underpinnings of retinal degenerative diseases. Building upon the development of modern techniques for gene delivery, many gene-based therapies have been effectively used to treat loss-of-function retinal diseases in mice and men. Significant effort has been invested into making gene delivery vehicles more efficient, less toxic, and non-immunogenic. However, one challenge for the treatment of more complex gain-of-function diseases, many of which might be benefited by the regulation of cellular stress-responsive signaling pathways, is the ability to control the strategy in a physiological (conditional) manner. This review is focused on promising retinal gene therapy strategies that rely on small molecule-based conditional regulation and the inherent limitations and challenges of these strategies that need to be addressed prior to their extensive use.
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18
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Flt3 Regulation in the Mononuclear Phagocyte System Promotes Ocular Neovascularization. J Ophthalmol 2018; 2018:2518568. [PMID: 29854425 PMCID: PMC5960574 DOI: 10.1155/2018/2518568] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 02/06/2018] [Indexed: 12/20/2022] Open
Abstract
Fms-like tyrosine kinase 3 (Flt3), a tyrosine kinase receptor expressed in CD34+ hematopoietic stem/progenitor cells, is important for both normal myeloid and lymphoid differentiation. It has been implicated in mice and humans for potential multilineage differentiation. We found that mice deficient in Flt3 or mice that received an Flt3 inhibitor (AC220) showed significantly reduced areas of ischemia-induced retinal neovascularization (RNV) and laser-induced choroidal NV (CNV) (P < 0.05). Increased Flt3 expression at the protein level was detected in retinas of oxygen-induced retinopathy (OIR) mice at P15 and P18 during retinal NV (RNV) progression. We subsequently found that macrophages (Mphi) polarization was regulated at the site of CNV in Flt3-deficient mice. Flow cytometry analysis demonstrated that Flt3 deficiency shifted Mphi polarization towards an M2 phenotype during RNV with significant reduction in M1 cytokine expression when compared to the wild-type controls (P < 0.05). Based on the above findings, we concluded that Flt3 inhibition alleviated ocular NV by promoting a Mphi polarization shift towards the M2 phenotype. Therapies targeting Flt3 may provide a new approach for the treatment of ocular NV.
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19
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Mousetap, a Novel Technique to Collect Uncontaminated Vitreous or Aqueous and Expand Usefulness of Mouse Models. Sci Rep 2018; 8:6371. [PMID: 29686307 PMCID: PMC5913258 DOI: 10.1038/s41598-018-24197-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 03/20/2018] [Indexed: 12/11/2022] Open
Abstract
Vitreous or aqueous humour taps are widely used in patients or large animals with retinal diseases to monitor disease biomarkers, search for novel biomarkers, assess the integrity of the blood-retinal barrier, or perform pharmacokinetic or pharmacodynamics studies. Although there are many useful mouse models of retinal diseases, the small size of mouse eyes has precluded vitreous or aqueous taps. Herein we describe a novel technique, mousetap, which allows collection of vitreous or aqueous humour uncontaminated by blood or tissue surrounding the vitreous cavity. Mousetap was used to obtain vitreous samples from several mouse models of retinal vascular diseases and vitreous albumin measured by ELISA was highly reproducible among mice of the same model. The mean vitreous albumin concentration differed widely among control mice and mice of different models and correlated with fluorescein angiographic assessment of vascular leakage severity. Protein arrays showed increases in levels of several vasoactive proteins in the vitreous from mice with oxygen-induced ischemic retinopathy compared with age-matched controls; almost all of these proteins are increased in the vitreous of patients with the most common human ischemic retinopathy, proliferative diabetic retinopathy. Thus, mousetap facilitates the use of mice for studies previously reserved for large animal models and patients.
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20
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Barben M, Schori C, Samardzija M, Grimm C. Targeting Hif1a rescues cone degeneration and prevents subretinal neovascularization in a model of chronic hypoxia. Mol Neurodegener 2018. [PMID: 29514656 PMCID: PMC5842520 DOI: 10.1186/s13024-018-0243-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Background Degeneration of cone photoreceptors leads to loss of vision in patients suffering from age-related macular degeneration (AMD) and other cone dystrophies. Evidence, such as choroidal ischemia and decreased choroidal blood flow, implicates reduced tissue oxygenation in AMD pathology and suggests a role of the cellular response to hypoxia in disease onset and progression. Such a chronic hypoxic situation may promote several cellular responses including stabilization of hypoxia-inducible factors (HIFs). Methods To investigate the consequence of a chronic activation of the molecular response to hypoxia in cones, von Hippel Lindau protein (VHL) was specifically ablated in cones of the all-cone R91W;Nrl-/- mouse. Retinal function and morphology was evaluated by ERG and light microscopy, while differential gene expression was tested by real-time PCR. Retinal vasculature was analyzed by immunostainings and fluorescein angiography. Two-way ANOVA with Šídák’s multiple comparison test was performed for statistical analysis. Results Cone-specific ablation of Vhl resulted in stabilization and activation of hypoxia-inducible factor 1A (HIF1A) which led to increased expression of genes associated with hypoxia and retinal stress. Our data demonstrate severe cone degeneration and pathologic vessel growth, features that are central to AMD pathology. Subretinal neovascularization was accompanied by vascular leakage and infiltration of microglia cells. Interestingly, we observed increased expression of tissue inhibitor of metalloproteinase 3 (Timp3) during the aging process, a gene associated with AMD and Bruch’s membrane integrity. Additional deletion of Hif1a protected cone cells, prevented pathological vessel growth and preserved vision. Conclusions Our data provide evidence for a HIF1A-mediated mechanism leading to pathological vessel growth and cone degeneration in response to a chronic hypoxia-like situation. Consequently, our results identify HIF1A as a potential therapeutic target to rescue hypoxia-related vision loss in patients.
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Affiliation(s)
- Maya Barben
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich (ZNZ), University of Zurich, Zurich, Switzerland
| | - Christian Schori
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.,Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
| | - Marijana Samardzija
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
| | - Christian Grimm
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich (ZNZ), University of Zurich, Zurich, Switzerland.,Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
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21
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Sui A, Zhong Y, Demetriades AM, Lu Q, Cai Y, Gao Y, Zhu Y, Shen X, Xie B. Inhibition of integrin α5β1 ameliorates VEGF-induced retinal neovascularization and leakage by suppressing NLRP3 inflammasome signaling in a mouse model. Graefes Arch Clin Exp Ophthalmol 2018; 256:951-961. [PMID: 29502235 PMCID: PMC5911279 DOI: 10.1007/s00417-018-3940-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 02/03/2018] [Accepted: 02/19/2018] [Indexed: 12/18/2022] Open
Abstract
PURPOSE To assess the effect of inhibiting integrin α5β1 by ATN-161 on vascular endothelial growth factor (VEGF)-induced neovascularization (NV) and leakage causing retinal detachment in adult Tet/opsin/VEGF transgenic mice, and characterize the underlying mechanism of its function. METHOD Retinas from adult Tet/opsin/VEGF transgenic mice and human retinal endothelial cells (HRECs) exposed to VEGF (treated with ATN-161 or PBS) were used to carry out immunofluorescence, RT-PCR and western blot to examine expression levels of integrin α5β1 and the NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome. Retinal frozen section analysis was used to assess NV and leakage causing retinal detachment. RESULTS In comparison to normal-treated mice, doxycycline-treated Tet/opsin/VEGF transgenic mice showed severe retinal detachment and higher integrin α5β1 expression. Furthermore, the retinal detachment was inhibited significantly by ATN-161. Additionally, ATN-161 treatment was associated with a conspicuous reduction in NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), cleaved caspase-1, and mature interleukin-1β expression levels in the retinas of Tet/opsin/VEGF transgenic mice treated with doxycycline as well as in HRECs exposed to VEGF. CONCLUSION ATN-161, an antagonist of integrin α5β1, is a promising treatment for retinal neovascularization (RNV), and its retinal protection role appears to take effect through inhibition of NLRP3 inflammasome activity.
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Affiliation(s)
- Ailing Sui
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yisheng Zhong
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Anna M Demetriades
- The Department of Ophthalmology, New York Presbyterian Hospital-Weill Cornell Medicine, New York, USA
| | - Qing Lu
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yujuan Cai
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yushuo Gao
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yanji Zhu
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xi Shen
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Bing Xie
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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22
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Silva RLE, Kanan Y, Mirando AC, Kim J, Shmueli RB, Lorenc VE, Fortmann SD, Sciamanna J, Pandey NB, Green JJ, Popel AS, Campochiaro PA. Tyrosine kinase blocking collagen IV-derived peptide suppresses ocular neovascularization and vascular leakage. Sci Transl Med 2018; 9. [PMID: 28100839 DOI: 10.1126/scitranslmed.aai8030] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Accepted: 11/30/2016] [Indexed: 01/20/2023]
Abstract
Vascular endothelial growth factor (VEGF)-neutralizing proteins provide benefit in several retinal and choroidal vascular diseases, but some patients still experience suboptimal outcomes, and the need for frequent intraocular injections is a barrier to good outcomes. A mimetic peptide derived from collagen IV, AXT107, suppressed subretinal neovascularization (NV) in two mouse models predictive of effects in neovascular age-related macular degeneration (NVAMD) and inhibited retinal NV in a model predictive of effects in ischemic retinopathies. A combination of AXT107 and the current treatment aflibercept suppressed subretinal NV better than either agent alone. Furthermore, AXT107 caused regression of choroidal NV. AXT107 reduced the VEGF-induced vascular leakage that underlies macular edema in ischemic retinopathies and NVAMD. In rabbit eyes, which are closer to the size of human eyes, intraocular injection of AXT107 significantly reduced VEGF-induced vascular leakage by 86% at 1 month and 70% at 2 months; aflibercept significantly reduced leakage by 69% at 1 month and did not reduce leakage at 2 months, demonstrating the longer effectiveness of AXT107. AXT107 reduced ligand-induced phosphorylation of multiple receptors: VEGFR2, c-Met, and PDGFRβ. Optimal signaling through these receptors requires complex formation with β3 integrin, which was reduced by AXT107 binding to αvβ3 AXT107 also reduced total VEGFR2 levels by increasing internalization, ubiquitination, and degradation. This biomimetic peptide is a sustained, multitargeted therapy that may provide advantages over intraocular injections of specific VEGF-neutralizing proteins.
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Affiliation(s)
- Raquel Lima E Silva
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Yogita Kanan
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Adam C Mirando
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jayoung Kim
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ron B Shmueli
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Valeria E Lorenc
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Seth D Fortmann
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jason Sciamanna
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Niranjan B Pandey
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,AsclepiX Therapeutics, LLC, Baltimore, MD 21211, USA
| | - Jordan J Green
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Institute for Nanobiotechnology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Aleksander S Popel
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Peter A Campochiaro
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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23
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Barben M, Samardzija M, Grimm C. The Role of Hypoxia, Hypoxia-Inducible Factor (HIF), and VEGF in Retinal Angiomatous Proliferation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1074:177-183. [PMID: 29721942 DOI: 10.1007/978-3-319-75402-4_22] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In industrialized countries, age-related macular degeneration (AMD) is the leading cause of blindness in elderly people. Hallmarks of the non-neovascular (dry) form of AMD are the formation of drusen and geographic atrophy, whereas the exudative (wet) form of the disease is characterized by invading blood vessels. In retinal angiomatous proliferation (RAP), a special form of wet AMD, intraretinal vessels grow from the deep plexus into the subretinal space. Little is known about the mechanisms leading to intraretinal neovascularization, but age-related changes such as reduction of choroidal blood flow, accumulation of drusen, and thickening of the Bruch's membrane may lead to reduced oxygen availability in photoreceptors. Such a chronic hypoxic situation may induce several cellular response pathways including the stabilization of hypoxia-inducible factors (HIFs) and the production of angiogenic factors, such as vascular endothelial growth factor (VEGF). Here, we discuss the potential contribution of hypoxia and HIFs in RAP disease pathology and in some mouse models for subretinal neovascularization.
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Affiliation(s)
- Maya Barben
- Lab for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Wagistr. 14, 8952, Schlieren, Switzerland
- Neuroscience Center Zurich (ZNZ), University of Zurich, Zurich, Switzerland
| | - Marijana Samardzija
- Lab for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Wagistr. 14, 8952, Schlieren, Switzerland
| | - Christian Grimm
- Lab for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Wagistr. 14, 8952, Schlieren, Switzerland.
- Neuroscience Center Zurich (ZNZ), University of Zurich, Zurich, Switzerland.
- Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland.
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24
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Liu Y, Fortmann SD, Shen J, Wielechowski E, Tretiakova A, Yoo S, Kozarsky K, Wang J, Wilson JM, Campochiaro PA. AAV8-antiVEGFfab Ocular Gene Transfer for Neovascular Age-Related Macular Degeneration. Mol Ther 2017; 26:542-549. [PMID: 29292162 DOI: 10.1016/j.ymthe.2017.12.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 11/27/2017] [Accepted: 12/02/2017] [Indexed: 12/11/2022] Open
Abstract
Sustained suppression of VEGF is needed in many patients with neovascular age-related macular degeneration (NVAMD), and gene transfer of a VEGF-neutralizing protein is a promising approach to achieve it. Initial clinical trials testing this approach have shown encouraging signals, but evidence of robust transgene expression and consistent antiangiogenic and antipermeability activity has been lacking. In this study, we demonstrate expression of an anti-human VEGF antibody fragment (antiVEGFfab) after subretinal injection of AAV8-antiVEGFfab. In transgenic mice expressing human VEGF in retina (rho/VEGF mice), a model of type 3 choroidal neovascularization (NV), eyes injected with ≥1 × 107 gene copies (GC) of AAV8-antiVEGFfab had significantly less mean area of NV than null vector-injected eyes. A dose-dependent response was observed with modest reduction of NV with ≤3 × 107, >50% reduction with ≥1 × 108 GC and almost complete elimination of NV with 3 × 109 or 1 × 1010 GC. In Tet/opsin/VEGF mice, in which doxycycline-induced high expression of VEGF leads to severe vascular leakage and exudative retinal detachment (RD), reduction of total RD by 70%-80% occurred with 3 × 109 or 1 × 1010 GC of AAV8-antiVEGFfab, an effect that was sustained for at least a month. These data strongly support initiating clinical trials testing subretinal injection of AAV8-antiVEGFfab in patients with NVAMD.
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Affiliation(s)
- Yuanyuan Liu
- Departments of Ophthalmology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Seth D Fortmann
- Departments of Ophthalmology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jikui Shen
- Departments of Ophthalmology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Erik Wielechowski
- Departments of Medicine and Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Anna Tretiakova
- Departments of Medicine and Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | | | | | - Jiangxia Wang
- Johns Hopkins Biostatistics Center, Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - James M Wilson
- Departments of Medicine and Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Peter A Campochiaro
- Departments of Ophthalmology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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25
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Ding K, Eaton L, Bowley D, Rieser M, Chang Q, Harris MC, Clabbers A, Dong F, Shen J, Hackett SF, Touw DS, Bixby J, Zhong S, Benatuil L, Bose S, Grinnell C, Preston GM, Iyer R, Sadhukhan R, Marchie S, Overmeyer G, Ghayur T, van Riet DA, Tang S, Campochario PA, Gu J. Generation and characterization of ABBV642, a dual variable domain immunoglobulin molecule (DVD-Ig) that potently neutralizes VEGF and PDGF-BB and is designed for the treatment of exudative age-related macular degeneration. MAbs 2017; 9:269-284. [PMID: 27929753 DOI: 10.1080/19420862.2016.1268305] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Exudative age-related macular degeneration (AMD) is the most common cause of moderate and severe vision loss in developed countries. Intraocular injections of vascular endothelial growth factor (VEGF or VEGF-A)-neutralizing proteins provide substantial benefit, but frequent, long-term injections are needed. In addition, many patients experience initial visual gains that are ultimately lost due to subretinal fibrosis. Preclinical studies and early phase clinical trials suggest that combined suppression of VEGF and platelet-derived growth factor-BB (PDGF-BB) provides better outcomes than suppression of VEGF alone, due to more frequent regression of neovascularization (NV) and suppression of subretinal fibrosis. We generated a dual variable domain immunoglobulin molecule, ABBV642 that specifically and potently binds and neutralizes VEGF and PDGF-BB. ABBV642 has been optimized for treatment of exudative AMD based on the following design characteristics: 1) high affinity binding to all VEGF-A isoforms and both soluble and extracellular matrix (ECM)-associated PDGF-BB; 2) potential for extended residence time in the vitreous cavity to decrease the frequency of intraocular injections; 3) rapid clearance from systemic circulation compared with molecules with wild type Fc region for normal FcRn binding, which may reduce the risk of systemic complications; and 4) low risk of potential effector function. The bispecificity of ABBV642 allows for a single injection of a single therapeutic agent, and thus a more streamlined development and regulatory path compared with combination products. In a mouse model of exudative AMD, ABBV642 was observed to be more effective than aflibercept. ABBV642 has potential to improve efficacy with reduced injection frequency in patients with exudative AMD, thereby reducing the enormous disease burden for patients and society.
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Affiliation(s)
- Kun Ding
- a John Hopkins Wilmer Eye Institute , Baltimore , MD , USA.,b State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University , Guangzhou , China
| | - Lucia Eaton
- c Immunology Discovery, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Diana Bowley
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | | | - Qing Chang
- c Immunology Discovery, AbbVie Bioresearch Center , Worcester , MA , USA.,d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Maria C Harris
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Anca Clabbers
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Feng Dong
- c Immunology Discovery, AbbVie Bioresearch Center , Worcester , MA , USA.,d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Jikui Shen
- a John Hopkins Wilmer Eye Institute , Baltimore , MD , USA
| | - Sean F Hackett
- a John Hopkins Wilmer Eye Institute , Baltimore , MD , USA
| | - Debra S Touw
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Jacqueline Bixby
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Suju Zhong
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Lorenzo Benatuil
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Sahana Bose
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | | | | | - Ramesh Iyer
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | | | - Susan Marchie
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Gary Overmeyer
- d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Tariq Ghayur
- c Immunology Discovery, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Deborah A van Riet
- c Immunology Discovery, AbbVie Bioresearch Center , Worcester , MA , USA
| | - Shibo Tang
- f Aier School of Ophthalmology, Central South University , Changsha , China
| | | | - Jijie Gu
- c Immunology Discovery, AbbVie Bioresearch Center , Worcester , MA , USA.,d Global Biologics, AbbVie Bioresearch Center , Worcester , MA , USA
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26
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Joyal JS, Gantner ML, Smith LEH. Retinal energy demands control vascular supply of the retina in development and disease: The role of neuronal lipid and glucose metabolism. Prog Retin Eye Res 2017; 64:131-156. [PMID: 29175509 DOI: 10.1016/j.preteyeres.2017.11.002] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 11/11/2017] [Accepted: 11/15/2017] [Indexed: 12/15/2022]
Affiliation(s)
- Jean-Sébastien Joyal
- Department of Pediatrics, Pharmacology and Ophthalmology, CHU Sainte-Justine Research Center, Université de Montréal, Montreal, Qc, Canada; Department of Pharmacology and Therapeutics, McGill University, Montreal, Qc, Canada.
| | - Marin L Gantner
- The Lowy Medical Research Institute, La Jolla, United States
| | - Lois E H Smith
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, 300 Longwood Avenue, Boston MA 02115, United States.
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27
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Liu Y, Shen J, Fortmann SD, Wang J, Vestweber D, Campochiaro PA. Reversible retinal vessel closure from VEGF-induced leukocyte plugging. JCI Insight 2017; 2:95530. [PMID: 28931763 DOI: 10.1172/jci.insight.95530] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 08/08/2017] [Indexed: 11/17/2022] Open
Abstract
Clinical trials in patients with macular edema due to diabetic retinopathy or retinal vein occlusion (RVO) have shown that suppression of VEGF not only improves macular edema, but also reopens closed retinal vessels, prevents progression of vessel closure, and improves retinopathy. In this study, we show the molecular basis for those clinical observations. Increased retinal levels of VEGF in mice cause plugging of retinal vessels with leukocytes, vessel closure, and hypoxia. Suppression of VEGF reduces leukocyte plugging, causing reperfusion of closed vessels. Activation of VEGFR1 contributes to leukocyte recruitment, because it is significantly reduced by an anti-VEGFR1-neutralizing antibody. High VEGF increases transcriptional activity of NF-κB and expression of NF-κB target genes, particularly Vcam1. Injection of an anti-VCAM-1-neutralizing antibody reduces VEGF-induced leukocyte plugging. These data explain the broad range of benefits obtained by VEGF suppression in patients with ischemic retinopathies, provide an important insight into the pathogenesis of RVO and diabetic retinopathy, and suggest that sustained suppression of VEGF early in the course of these diseases may prevent vessel closure, worsening ischemia, and disease progression. This study also identifies VEGFR1 and VCAM-1 as molecular targets whose suppression could supplement VEGF neutralization for treatment of RVO and diabetic retinopathy.
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Affiliation(s)
- Yuanyuan Liu
- Department of Ophthalmology and.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jikui Shen
- Department of Ophthalmology and.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Seth D Fortmann
- Department of Ophthalmology and.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jiangxia Wang
- Johns Hopkins Biostatistics Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Dietmar Vestweber
- Department of Cell Biology, Max-Planck-Institute of Molecular Biomedicine, Muenster, Germany
| | - Peter A Campochiaro
- Department of Ophthalmology and.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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28
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Endothelial adenosine A2a receptor-mediated glycolysis is essential for pathological retinal angiogenesis. Nat Commun 2017; 8:584. [PMID: 28928465 PMCID: PMC5605640 DOI: 10.1038/s41467-017-00551-2] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 06/21/2017] [Indexed: 01/14/2023] Open
Abstract
Adenosine/adenosine receptor-mediated signaling has been implicated in the development of various ischemic diseases, including ischemic retinopathies. Here, we show that the adenosine A2a receptor (ADORA2A) promotes hypoxia-inducible transcription factor-1 (HIF-1)-dependent endothelial cell glycolysis, which is crucial for pathological angiogenesis in proliferative retinopathies. Adora2a expression is markedly increased in the retina of mice with oxygen-induced retinopathy (OIR). Endothelial cell-specific, but not macrophage-specific Adora2a deletion decreases key glycolytic enzymes and reduces pathological neovascularization in the OIR mice. In human primary retinal microvascular endothelial cells, hypoxia induces the expression of ADORA2A by activating HIF-2α. ADORA2A knockdown decreases hypoxia-induced glycolytic enzyme expression, glycolytic flux, and endothelial cell proliferation, sprouting and tubule formation. Mechanistically, ADORA2A activation promotes the transcriptional induction of glycolytic enzymes via ERK- and Akt-dependent translational activation of HIF-1α protein. Taken together, these findings advance translation of ADORA2A as a therapeutic target in the treatment of proliferative retinopathies and other diseases dependent on pathological angiogenesis.Pathological angiogenesis in the retina is a major cause of blindness. Here the authors show that adenosine receptor A2A drives pathological angiogenesis in the oxygen-induced retinopathy mouse model by promoting glycolysis in endothelial cells via the ERK/Akt/HIF-1α pathway, thereby suggesting new therapeutic targets for disease treatment.
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29
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Feng L, Ju M, Lee KYV, Mackey A, Evangelista M, Iwata D, Adamson P, Lashkari K, Foxton R, Shima D, Ng YS. A Proinflammatory Function of Toll-Like Receptor 2 in the Retinal Pigment Epithelium as a Novel Target for Reducing Choroidal Neovascularization in Age-Related Macular Degeneration. THE AMERICAN JOURNAL OF PATHOLOGY 2017; 187:2208-2221. [PMID: 28739342 DOI: 10.1016/j.ajpath.2017.06.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 05/16/2017] [Accepted: 06/08/2017] [Indexed: 11/28/2022]
Abstract
Current treatments for choroidal neovascularization, a major cause of blindness for patients with age-related macular degeneration, treat symptoms but not the underlying causes of the disease. Inflammation has been strongly implicated in the pathogenesis of choroidal neovascularization. We examined the inflammatory role of Toll-like receptor 2 (TLR2) in age-related macular degeneration. TLR2 was robustly expressed by the retinal pigment epithelium in mouse and human eyes, both normal and with macular degeneration/choroidal neovascularization. Nuclear localization of NF-κB, a major downstream target of TLR2 signaling, was detected in the retinal pigment epithelium of human eyes, particularly in eyes with advanced stages of age-related macular degeneration. TLR2 antagonism effectively suppressed initiation and growth of spontaneous choroidal neovascularization in a mouse model, and the combination of anti-TLR2 and antivascular endothelial growth factor receptor 2 yielded an additive therapeutic effect on both area and number of spontaneous choroidal neovascularization lesions. Finally, in primary human fetal retinal pigment epithelium cells, ligand binding to TLR2 induced robust expression of proinflammatory cytokines, and end products of lipid oxidation had a synergistic effect on TLR2 activation. Our data illustrate a functional role for TLR2 in the pathogenesis of choroidal neovascularization, likely by promoting inflammation of the retinal pigment epithelium, and validate TLR2 as a novel therapeutic target for reducing choroidal neovascularization.
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Affiliation(s)
- Lili Feng
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
| | - Meihua Ju
- University College of London Institute of Ophthalmology, London, United Kingdom; Department of Ocular Biology and Therapeutics, University College of London Institute of Ophthalmology, London, United Kingdom
| | - Kei Ying V Lee
- University College of London Institute of Ophthalmology, London, United Kingdom; Department of Ocular Biology and Therapeutics, University College of London Institute of Ophthalmology, London, United Kingdom
| | - Ashley Mackey
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
| | - Mariasilvia Evangelista
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
| | - Daiju Iwata
- University College of London Institute of Ophthalmology, London, United Kingdom; Department of Ocular Biology and Therapeutics, University College of London Institute of Ophthalmology, London, United Kingdom
| | - Peter Adamson
- University College of London Institute of Ophthalmology, London, United Kingdom
| | - Kameran Lashkari
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
| | - Richard Foxton
- University College of London Institute of Ophthalmology, London, United Kingdom; Department of Ocular Biology and Therapeutics, University College of London Institute of Ophthalmology, London, United Kingdom
| | - David Shima
- University College of London Institute of Ophthalmology, London, United Kingdom; Department of Ocular Biology and Therapeutics, University College of London Institute of Ophthalmology, London, United Kingdom
| | - Yin Shan Ng
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts.
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30
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Dong Y, Cai X, Wu Y, Liu Y, Deng L, Chen H. Insights from Genetic Model Systems of Retinal Degeneration: Role of Epsins in Retinal Angiogenesis and VEGFR2 Signaling. JOURNAL OF NATURE AND SCIENCE 2017; 3:e281. [PMID: 28191500 PMCID: PMC5303005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The retina is a light sensitive tissue that contains specialized photoreceptor cells called rods and cones which process visual signals. These signals are relayed to the brain through interneurons and the fibers of the optic nerve. The retina is susceptible to a variety of degenerative diseases, including age-related macular degeneration (AMD), diabetic retinopathy (DR), retinitis pigmentosa (RP) and other inherited retinal degenerations. In order to reveal the mechanism underlying these diseases and to find methods for the prevention/treatment of retinal degeneration, animal models have been generated to mimic human eye diseases. In this paper, several well-characterized and commonly used animal models are reviewed. Of particular interest are the contributions of these models to our understanding of the mechanisms of retinal degeneration and thereby providing novel treatment options including gene therapy, stem cell therapy, nanomedicine, and CRISPR/Cas9 genome editing. Role of newly-identified adaptor protein epsins from our laboratory is discussed in retinal angiogenesis and VEGFR2 signaling.
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Affiliation(s)
- Yunzhou Dong
- Vascular Biology Program, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Xue Cai
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Yong Wu
- Department of Internal Medicine, Charles R. Drew University of Medicine & Sciences, University of California School of Medicine, Los Angeles, CA 90059, USA
| | - Yanjun Liu
- Department of Internal Medicine, Charles R. Drew University of Medicine & Sciences, University of California School of Medicine, Los Angeles, CA 90059, USA
| | - Lin Deng
- Department of Biological Chemistry & Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Hong Chen
- Vascular Biology Program, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA
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31
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Abstract
Tie2 is a tyrosine kinase receptor located predominantly on vascular endothelial cells that plays a central role in vascular stability. Angiopoietin-1 (Angpt1), produced by perivascular cells, binds, clusters, and activates Tie2, leading to Tie2 autophosphorylation and downstream signaling. Activated Tie2 increases endothelial cell survival, adhesion, and cell junction integrity, thereby stabilizing the vasculature. Angiopoietin-2 (Angpt2) and vascular endothelial-protein tyrosine phosphatase (VE-PTP) are negative regulators increased by hypoxia; they inactivate Tie2, destabilizing the vasculature and increasing responsiveness to vascular endothelial growth factor (VEGF) and other inflammatory cytokines that stimulate vascular leakage and neovascularization. AKB-9778 is a small-molecule antagonist of VE-PTP which increases phosphorylation of Tie2 even in the presence of high Angpt2 levels. In preclinical studies, AKB-9778 reduced VEGF-induced leakage and ocular neovascularization (NV) and showed additive benefit when combined with VEGF suppression. In two clinical trials in diabetic macular edema (DME) patients, subcutaneous injections of AKB-9778 were safe and provided added benefit to VEGF suppression. Preliminary data suggest that AKB-9778 monotherapy improves diabetic retinopathy. These data suggest that Tie2 activation may be a valuable strategy to treat or prevent diabetic retinopathy.
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Affiliation(s)
- Peter A Campochiaro
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- The Wilmer Eye Institute, The Johns Hopkins School of Medicine, 815 Maumenee, 600 N. Wolfe Street, Baltimore, MD, 21287-9277, USA.
| | - Kevin G Peters
- Aerpio Therapeutics, 9987 Carver Road, Cincinnati, OH, USA
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32
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Grob SR, Finn A, Papakostas TD, Eliott D. Clinical Trials in Retinal Dystrophies. Middle East Afr J Ophthalmol 2016; 23:49-59. [PMID: 26957839 PMCID: PMC4759904 DOI: 10.4103/0974-9233.173135] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Research development is burgeoning for genetic and cellular therapy for retinal dystrophies. These dystrophies are the focus of many research efforts due to the unique biology and accessibility of the eye, the transformative advances in ocular imaging technology that allows for in vivo monitoring, and the potential benefit people would gain from success in the field – the gift of renewed sight. Progress in the field has revealed the immense complexity of retinal dystrophies and the challenges faced by researchers in the development of this technology. This study reviews the current trials and advancements in genetic and cellular therapy in the treatment of retinal dystrophies and also discusses the current and potential future challenges.
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Affiliation(s)
- Seanna R Grob
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA; Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
| | - Avni Finn
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA; Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
| | - Thanos D Papakostas
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA; Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA; Retina, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
| | - Dean Eliott
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA; Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA; Retina, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
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33
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Liu X, Dreffs A, Díaz-Coránguez M, Runkle EA, Gardner TW, Chiodo VA, Hauswirth WW, Antonetti DA. Occludin S490 Phosphorylation Regulates Vascular Endothelial Growth Factor-Induced Retinal Neovascularization. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:2486-99. [PMID: 27423695 DOI: 10.1016/j.ajpath.2016.04.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 04/07/2016] [Accepted: 04/26/2016] [Indexed: 01/01/2023]
Abstract
Occludin is a transmembrane tight junction protein that contributes to diverse cellular functions, including control of barrier properties, cell migration, and proliferation. Vascular endothelial growth factor (VEGF) induces phosphorylation of occludin at S490, which is required for VEGF-induced endothelial permeability. Herein, we demonstrate that occludin S490 phosphorylation also regulates VEGF-induced retinal endothelial cell proliferation and neovascularization. Using a specific antibody, phospho-occludin was located in centrosomes in endothelial cell cultures, animal models, and human surgical samples of retinal neovessels. Occludin S490 phosphorylation was found to increase with endothelial tube formation in vitro and in vivo during retinal neovascularization after induction of VEGF expression. More important, expression of occludin mutated at S490 to Ala, completely inhibited angiogenesis in cell culture models and in vivo. Collectively, these data suggest a novel role for occludin in regulation of endothelial proliferation and angiogenesis in a phosphorylation-dependent manner. These findings may lead to methods of regulating pathological neovascularization by specifically targeting endothelial cell proliferation.
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Affiliation(s)
- Xuwen Liu
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan
| | - Alyssa Dreffs
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan
| | - Monica Díaz-Coránguez
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan
| | - E Aaron Runkle
- Department of Pathology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Thomas W Gardner
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan
| | - Vince A Chiodo
- Department of Ophthalmology, University of Florida, Gainesville, Florida
| | | | - David A Antonetti
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan.
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Kunhiraman H, Edatt L, Thekkeveedu S, Poyyakkara A, Raveendran V, Kiran MS, Sudhakaran P, Kumar SVB. 2-Deoxy Glucose Modulates Expression and Biological Activity of VEGF in a SIRT-1 Dependent Mechanism. J Cell Biochem 2016; 118:252-262. [PMID: 27302189 DOI: 10.1002/jcb.25629] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 06/13/2016] [Indexed: 01/24/2023]
Abstract
Reprogramming of energy metabolism particularly switching over of cells to aerobic glycolysis leading to accumulation of lactate is a hallmark of cancer. Lactate can induce angiogenesis, an important process underlying tumor growth and metastasis. VEGF is one of the most important cytokines which regulate this process and the present study was designed to examine if blocking glycolytic pathway in tumor cells can affect its angiogenic potency with respect to VEGF. For this, the expression and biological activity of VEGF synthesized and secreted by tumor derived cell lines in the presence or absence of 2-deoxy glucose (2-DG), an inhibitor of glycolysis was determined. The results suggested that inhibition of glycolysis using sub-lethal doses of 2-DG down-regulated the expression of VEGF and also significantly reduced its biological activity. Further mechanistic studies revealed that the down regulation of VEGF gene expression by 2-DG was due to an increase in SIRT-1 activity and the reduced biological activity was found to be due to an increase in the PAR modification of VEGF. Activity of SIRT-1 and PAR modification of VEGF in turn, was found to be correlated to the cellular NAD+ levels. The results presented here therefore suggest that treatment of cancer cells with 2-DG can significantly reduce its overall angiogenic potency through transcriptional and post-translational mechanisms. J. Cell. Biochem. 118: 252-262, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Haritha Kunhiraman
- Department of Biochemistry and Molecular Biology, Central University of Kerala, Kasargod, India
| | - Lincy Edatt
- Department of Biochemistry and Molecular Biology, Central University of Kerala, Kasargod, India
| | - Sruthi Thekkeveedu
- Department of Biochemistry and Molecular Biology, Central University of Kerala, Kasargod, India
| | - Aswini Poyyakkara
- Department of Biochemistry and Molecular Biology, Central University of Kerala, Kasargod, India
| | - Viji Raveendran
- Department of Plant Science, Central University of Kerala, Kasargod, India
- IUCGGT, University of Kerala, Karyavattom, Trivandrum, India
| | | | - Perumana Sudhakaran
- IUCGGT, University of Kerala, Karyavattom, Trivandrum, India
- Department of Computational Biology and Bioinformatics, University of Kerala, Karyavattom, Trivandrum, India
| | - Sameer V B Kumar
- Department of Biochemistry and Molecular Biology, Central University of Kerala, Kasargod, India
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Subhani S, Vavilala DT, Mukherji M. HIF inhibitors for ischemic retinopathies and cancers: options beyond anti-VEGF therapies. Angiogenesis 2016; 19:257-73. [DOI: 10.1007/s10456-016-9510-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 04/16/2016] [Indexed: 12/15/2022]
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Joyal JS, Sun Y, Gantner ML, Shao Z, Evans LP, Saba N, Fredrick T, Burnim S, Kim JS, Patel G, Juan AM, Hurst CG, Hatton CJ, Cui Z, Pierce KA, Bherer P, Aguilar E, Powner MB, Vevis K, Boisvert M, Fu Z, Levy E, Fruttiger M, Packard A, Rezende FA, Maranda B, Sapieha P, Chen J, Friedlander M, Clish CB, Smith LE. Retinal lipid and glucose metabolism dictates angiogenesis through the lipid sensor Ffar1. Nat Med 2016; 22:439-45. [PMID: 26974308 PMCID: PMC4823176 DOI: 10.1038/nm.4059] [Citation(s) in RCA: 171] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 02/05/2016] [Indexed: 02/06/2023]
Abstract
Tissues with high metabolic rates often use lipids, as well as glucose, for energy, conferring a survival advantage during feast and famine. Current dogma suggests that high-energy-consuming photoreceptors depend on glucose. Here we show that the retina also uses fatty acid β-oxidation for energy. Moreover, we identify a lipid sensor, free fatty acid receptor 1 (Ffar1), that curbs glucose uptake when fatty acids are available. Very-low-density lipoprotein receptor (Vldlr), which is present in photoreceptors and is expressed in other tissues with a high metabolic rate, facilitates the uptake of triglyceride-derived fatty acid. In the retinas of Vldlr(-/-) mice with low fatty acid uptake but high circulating lipid levels, we found that Ffar1 suppresses expression of the glucose transporter Glut1. Impaired glucose entry into photoreceptors results in a dual (lipid and glucose) fuel shortage and a reduction in the levels of the Krebs cycle intermediate α-ketoglutarate (α-KG). Low α-KG levels promotes stabilization of hypoxia-induced factor 1a (Hif1a) and secretion of vascular endothelial growth factor A (Vegfa) by starved Vldlr(-/-) photoreceptors, leading to neovascularization. The aberrant vessels in the Vldlr(-/-) retinas, which invade normally avascular photoreceptors, are reminiscent of the vascular defects in retinal angiomatous proliferation, a subset of neovascular age-related macular degeneration (AMD), which is associated with high vitreous VEGFA levels in humans. Dysregulated lipid and glucose photoreceptor energy metabolism may therefore be a driving force in macular telangiectasia, neovascular AMD and other retinal diseases.
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Affiliation(s)
- Jean-Sébastien Joyal
- Department of Pediatrics, CHU Sainte-Justine Research Center, Université de Montréal, Montreal, Qc, Ca
- Department of Pharmacology, CHU Sainte-Justine Research Center, Université de Montréal, Montreal, Qc, Ca
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Qc, Ca
| | - Ye Sun
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Qc, Ca
| | | | - Zhuo Shao
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
| | - Lucy P. Evans
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
| | - Nicholas Saba
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
| | - Thomas Fredrick
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
| | - Samuel Burnim
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
| | - Jin Sung Kim
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Qc, Ca
| | - Gauri Patel
- Department of Pharmacology, CHU Sainte-Justine Research Center, Université de Montréal, Montreal, Qc, Ca
| | - Aimee M. Juan
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Qc, Ca
| | - Christian G. Hurst
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
| | - Colman J. Hatton
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
| | - Zhenghao Cui
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
| | - Kerry A. Pierce
- Metabolite Profiling Platform, The Broad Institute of MIT and Harvard University, Cambridge, MA, USA
| | - Patrick Bherer
- Department of Genetics, Université de Sherbrooke, Sherbrooke, Qc, Ca
| | - Edith Aguilar
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA, USA
| | | | - Kristis Vevis
- Institute of Ophthalmology, University College London, London, UK
| | - Michel Boisvert
- Department of Nutrition, CHU Sainte-Justine Research Center, Université de Montreal, Montreal, Qc, Ca
| | - Zhongjie Fu
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
| | - Emile Levy
- Department of Nutrition, CHU Sainte-Justine Research Center, Université de Montreal, Montreal, Qc, Ca
| | - Marcus Fruttiger
- Institute of Ophthalmology, University College London, London, UK
| | - Alan Packard
- Radiology, Harvard Medical School, Boston Children's Hospital, MA. USA
| | - Flavio A. Rezende
- Department of Ophthalmology, Maisonneuve-Rosemont Hospital Research Centre, Université de Montréal, Montreal, Qc, Ca
| | - Bruno Maranda
- Department of Genetics, Université de Sherbrooke, Sherbrooke, Qc, Ca
| | - Przemyslaw Sapieha
- Department of Ophthalmology, Maisonneuve-Rosemont Hospital Research Centre, Université de Montréal, Montreal, Qc, Ca
| | - Jing Chen
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
| | - Martin Friedlander
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Clary B. Clish
- Metabolite Profiling Platform, The Broad Institute of MIT and Harvard University, Cambridge, MA, USA
| | - Lois E.H. Smith
- Department of Ophthalmology, Harvard Medical School, Boston Children's Hospital, MA, USA
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Zhu Y, Tan W, Demetriades AM, Cai Y, Gao Y, Sui A, Lu Q, Shen X, Jiang C, Xie B, Sun X. Interleukin-17A neutralization alleviated ocular neovascularization by promoting M2 and mitigating M1 macrophage polarization. Immunology 2016; 147:414-28. [PMID: 26694999 DOI: 10.1111/imm.12571] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 12/08/2015] [Accepted: 12/16/2015] [Indexed: 01/24/2023] Open
Abstract
Neovascularization (NV), as a cardinal complication of several ocular diseases, has been intensively studied, and research has shown its close association with inflammation and immune cells. In the present study, the role of interleukin-17A (IL-17A) in angiogenesis in the process of ocular NV both in vivo and in vitro was investigated. Also, a paracrine role of IL-17A was demonstrated in the crosstalk between endothelial cells and macrophages in angiogenesis. In the retinas of mice with retinopathy of prematurity, the IL-17A expression increased significantly at postnatal day 15 (P15) and P18 during retinal NV. Mice given IL-17A neutralizing antibody (NAb) developed significantly reduced choroidal NV and retinal NV. Studies on vascular endothelial growth factor (VEGF) over-expressing mice suggested that IL-17A modulated NV through the VEGF pathway. Furthermore, IL-17A deficiency shifted macrophage polarization toward an M2 phenotype during retinal NV with significantly reduced M1 cytokine expression compared with wild-type controls. In vitro assays revealed that IL-17A treated macrophage supernatant gave rise to elevated human umbilical vascular endothelial cell proliferation, tube formation and VEGF receptor 1 and receptor 2 expression. Therefore, IL-17A could potentially serve as a novel target for treating ocular NV diseases. The limitation of this study involved the potential mechanisms, such as which transcription accounted for macrophage polarization and how the subsequent cytokines were modulated when macrophages were polarized. Further studies need to be undertaken to definitively determine the extent to which IL-17A neutralizing anti-angiogenic activity depends on macrophage modulation compared with anti-VEGF treatment.
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Affiliation(s)
- Yanji Zhu
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wei Tan
- The Department of Ophthalmology, The First People's Hospital, The Third Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China
| | - Anna M Demetriades
- The Department of Ophthalmology, Presbyterian Hospital-Cornell, New York, NY, USA
| | - Yujuan Cai
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yushuo Gao
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ailing Sui
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Qing Lu
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xi Shen
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chunhui Jiang
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai, China
| | - Bing Xie
- The Department of Ophthalmology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xinghuai Sun
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai, China
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Ratson R, Sheiner E, Davidson E, Sergienko R, Beharier O, Kessous R. Fertility treatments and the risk for ophthalmic complications: a cohort study with 25-year follow-up. J Matern Fetal Neonatal Med 2015; 29:3094-7. [DOI: 10.3109/14767058.2015.1120717] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Roy Ratson
- Department of Obstetrics and Gynecology, Faculty of Health Sciences, Soroka University Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel,
| | - Eyal Sheiner
- Department of Obstetrics and Gynecology, Faculty of Health Sciences, Soroka University Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel,
| | - Ehud Davidson
- Faculty of Health Sciences, Soroka University Medical Center, Clalit Health Services (Southern District), Ben-Gurion University of the Negev, Beer-Sheva, Israel, and
| | - Ruslan Sergienko
- Department of Public Health, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ofer Beharier
- Department of Obstetrics and Gynecology, Faculty of Health Sciences, Soroka University Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel,
| | - Roy Kessous
- Department of Obstetrics and Gynecology, Faculty of Health Sciences, Soroka University Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel,
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Lin F, Chen BL, Wang YZ, Gao D, Song J, Kaptchuk TJ, Chen KJ. In Vitro Angiogenesis Effect of Xuefu Zhuyu Decoction () and Vascular Endothelial Growth Factor: A Comparison Study. Chin J Integr Med 2015; 24:606-612. [PMID: 26272550 DOI: 10.1007/s11655-015-2289-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2014] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To compare the angiogenesis behaviors of vascular endothelial growth factor (VEGF) and Chinese medicine Xuefu Zhuyu Decoction (, XZD) treatments. METHODS Human microvascular endothelial cells (HMEC-1) were treated with various concentrations of either XZD-containing serum (XZD-CS) or VEGF for 24, 48, and 72 h, respectively. Cell viability, proliferation, migration, adhesion, and in vitro tube formation assays were used to assess their angiogenic effects. RESULTS VEGF promoted all cellular phases involved in angiogenesis including cell viability, proliferation, migration, adhesion, and tube formation (<0.05 or <0.01). Unlike the continuous promotion effects of VEGF at the above stages, XZD inhibited cell viability and proliferation (<0.05 or <0.01) and only promoted tube formation in the early phase of angiogenesis (<0.01). CONCLUSIONS These two medications promote different angiogenesis behaviors, which might be an important reason for their distinct therapeutic profile in clinical usage.
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Affiliation(s)
- Fan Lin
- College of Integrative Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, 350122, China
| | - Bin-Ling Chen
- The Second Hospital of Longyan, Longyan, Fujian Province, 364000, China
| | - Yi-Zheng Wang
- College of Integrative Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, 350122, China
| | - Dong Gao
- College of Integrative Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, 350122, China.
| | - Jun Song
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, 100700, China.
| | - T J Kaptchuk
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Ke-Ji Chen
- Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, 100091, China
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Campochiaro PA. Molecular pathogenesis of retinal and choroidal vascular diseases. Prog Retin Eye Res 2015; 49:67-81. [PMID: 26113211 DOI: 10.1016/j.preteyeres.2015.06.002] [Citation(s) in RCA: 356] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 06/09/2015] [Accepted: 06/16/2015] [Indexed: 02/06/2023]
Abstract
There are two major types of ocular neovascularization that affect the retina, retinal neovascularization (NV) and subretinal or choroidal NV. Retinal NV occurs in a group of diseases referred to as ischemic retinopathies in which damage to retinal vessels results in retinal ischemia. Most prevalent of these are diabetic retinopathy and retinal vein occlusions. Subretinal and choroidal NV occur in diseases of the outer retina and Bruch's membrane, the most prevalent of which is age-related macular degeneration. Numerous studies in mouse models have helped to elucidate the molecular pathogenesis underlying retinal, subretinal, and choroidal NV. There is considerable overlap because the precipitating event in each is stabilization of hypoxia inducible factor-1 (HIF-1) which leads to upregulation of several hypoxia-regulated gene products, including vascular endothelial growth factor (VEGF), angiopoietin 2, vascular endothelial-protein tyrosine phosphatase (VE-PTP), and several others. Stimulation of VEGF signaling and suppression of Tie2 by angiopoietin 2 and VE-PTP are critical for sprouting of retinal, subretinal, and choroidal NV, with perturbation of Bruch's membrane also needed for the latter. Additional HIF-1-regulated gene products cause further stimulation of the NV. It is difficult to model macular edema in animals and therefore proof-of-concept clinical trials were done and demonstrated that VEGF plays a central role and that suppression of Tie2 is also important. Neutralization of VEGF is currently the first line therapy for all of the above disease processes, but new treatments directed at some of the other molecular targets, particularly stabilization of Tie2, are likely to provide additional benefit for subretinal/choroidal NV and macular edema. In addition, the chronicity of these diseases as well as the implication of VEGF as a cause of retinal nonperfusion and progression of background diabetic retinopathy make sustained delivery approaches for VEGF antagonists a priority.
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Affiliation(s)
- Peter A Campochiaro
- Departments of Ophthalmology and Neuroscience, Maumenee 815, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, Baltimore, MD 21287-9277, USA.
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Angiopoietin-like 4 is a potent angiogenic factor and a novel therapeutic target for patients with proliferative diabetic retinopathy. Proc Natl Acad Sci U S A 2015; 112:E3030-9. [PMID: 26039997 PMCID: PMC4466723 DOI: 10.1073/pnas.1423765112] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In proliferative diabetic retinopathy (PDR), the most vision-threatening sequela of diabetic eye disease, retinal ischemia leads to increased expression of angiogenic factors that promote neovascularization. Although therapies targeting the potent angiogenic mediator vascular endothelial growth factor have been remarkably successful for the treatment of diabetic macular edema, this approach has not proven sufficient to prevent the development of retinal neovascularization, implicating additional angiogenic factor(s) in PDR pathogenesis. We demonstrate here that angiopoietin-like 4 is a potent angiogenic mediator with markedly increased expression in the eyes of PDR patients. Our studies identify a novel therapeutic target for the treatment of ocular neovascular disease and may have broad implications for the treatment of other diseases dependent on pathologic angiogenesis. Diabetic eye disease is the most common cause of severe vision loss in the working-age population in the developed world, and proliferative diabetic retinopathy (PDR) is its most vision-threatening sequela. In PDR, retinal ischemia leads to the up-regulation of angiogenic factors that promote neovascularization. Therapies targeting vascular endothelial growth factor (VEGF) delay the development of neovascularization in some, but not all, diabetic patients, implicating additional factor(s) in PDR pathogenesis. Here we demonstrate that the angiogenic potential of aqueous fluid from PDR patients is independent of VEGF concentration, providing an opportunity to evaluate the contribution of other angiogenic factor(s) to PDR development. We identify angiopoietin-like 4 (ANGPTL4) as a potent angiogenic factor whose expression is up-regulated in hypoxic retinal Müller cells in vitro and the ischemic retina in vivo. Expression of ANGPTL4 was increased in the aqueous and vitreous of PDR patients, independent of VEGF levels, correlated with the presence of diabetic eye disease, and localized to areas of retinal neovascularization. Inhibition of ANGPTL4 expression reduced the angiogenic potential of hypoxic Müller cells; this effect was additive with inhibition of VEGF expression. An ANGPTL4 neutralizing antibody inhibited the angiogenic effect of aqueous fluid from PDR patients, including samples from patients with low VEGF levels or receiving anti-VEGF therapy. Collectively, our results suggest that targeting both ANGPTL4 and VEGF may be necessary for effective treatment or prevention of PDR and provide the foundation for studies evaluating aqueous ANGPTL4 as a biomarker to help guide individualized therapy for diabetic eye disease.
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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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Shen J, Frye M, Lee BL, Reinardy JL, McClung JM, Ding K, Kojima M, Xia H, Seidel C, Lima e Silva R, Dong A, Hackett SF, Wang J, Howard BW, Vestweber D, Kontos CD, Peters KG, Campochiaro PA. Targeting VE-PTP activates TIE2 and stabilizes the ocular vasculature. J Clin Invest 2014; 124:4564-76. [PMID: 25180601 DOI: 10.1172/jci74527] [Citation(s) in RCA: 155] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 07/24/2014] [Indexed: 01/01/2023] Open
Abstract
Retinal and choroidal neovascularization (NV) and vascular leakage contribute to visual impairment in several common ocular diseases. The angiopoietin/TIE2 (ANG/TIE2) pathway maintains vascular integrity, and negative regulators of this pathway are potential therapeutic targets for these diseases. Here, we demonstrated that vascular endothelial-protein tyrosine phosphatase (VE-PTP), which negatively regulates TIE2 activation, is upregulated in hypoxic vascular endothelial cells, particularly in retinal NV. Intraocular injection of an anti-VE-PTP antibody previously shown to activate TIE2 suppressed ocular NV. Furthermore, a small-molecule inhibitor of VE-PTP catalytic activity (AKB-9778) activated TIE2, enhanced ANG1-induced TIE2 activation, and stimulated phosphorylation of signaling molecules in the TIE2 pathway, including AKT, eNOS, and ERK. In mouse models of neovascular age-related macular degeneration, AKB-9778 induced phosphorylation of TIE2 and strongly suppressed NV. Ischemia-induced retinal NV, which is relevant to diabetic retinopathy, was accentuated by the induction of ANG2 but inhibited by AKB-9778, even in the presence of high levels of ANG2. AKB-9778 also blocked VEGF-induced leakage from dermal and retinal vessels and prevented exudative retinal detachments in double-transgenic mice with high expression of VEGF in photoreceptors. These data support targeting VE-PTP to stabilize retinal and choroidal blood vessels and suggest that this strategy has potential for patients with a wide variety of retinal and choroidal vascular diseases.
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Nuclear factor kappa-B signaling is integral to ocular neovascularization in ischemia-independent microenvironment. PLoS One 2014; 9:e101602. [PMID: 25050547 PMCID: PMC4106825 DOI: 10.1371/journal.pone.0101602] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 06/09/2014] [Indexed: 01/24/2023] Open
Abstract
Retinal ischemia promotes the upregulation of VEGF expression and accounts for most pathological features of retinal neovascularization (NV). Paradoxically, VEGF remains the pivotal stimulator of ocular NV, despite the absence of ischemia. Therefore, the central question arises as to how the various molecular mechanisms interplay in ischemia-independent NV. It's been suggested that NFκB plays a crucial role in the pathogenesis of diabetic vasculopathies. Here, we dissected the molecular mechanism of ocular NV in the rho/VEGF transgenic mouse model, which develops subretinal NV in ischemia-independent microenvironment. Furthermore, we examined whether intravitreal administration of YC-1, a HIF-1 inhibitor, can modulate the activation of NFκB and its downstream angiogenic signaling in the mouse retina. We demonstrated that YC-1 inhibited retinal NFκB/p65 DNA binding activity and downregulated NFκB/p65, FAK, α5β1, EPO, ET-1, and MMP-9 expression at the message and the protein levels. In addition, YC-1 significantly inhibited subretinal NV by reducing the number of neovascular lesions, the area of each lesion and the total area of NV per retina. We further investigated the influence of VEGF signaling pathway on HIF-1α transcriptional activity to substantiate that this mouse model develops subretinal NV in an ischemia-independent microenvironment. Our data demonstrated that VEGF overexpression didn't have any impact on HIF-1α transcriptional activity, whereas treatment with YC-1 significantly inhibited endogenous HIF-1 activity. Our study suggests that retinal NFκB transcriptional activity is pivotal to ischemia-independent mechanisms, which lead to the local activation of angiogenic cascades. Our data also indicate that the nexus between VEGF and NFκB is implicated in triggering the angiogenic cascade that promotes retinal NV. Hence, targeting the VEGF/NFκB axis may act in a negative feedback loop to suppress ocular NV. This study suggests that inhibition of NFκB activation may be a means of turning off a “master switch” responsible for initiating and perpetuating these ocular pathologies.
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Badaro E, Novais EA, Abdala K, Chun M, Urias M, de Arruda Melo Filho PA, Farah ME, Rodrigues EB. Development of an experimental model of proliferative retinopathy by intravitreal injection of VEGF165. J Ocul Pharmacol Ther 2014; 30:752-6. [PMID: 25029288 DOI: 10.1089/jop.2014.0036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE To develop an experimental model of proliferative retinopathy by intravitreal injection of vascular endothelial growth factor 165 (VEGF165) in pigmented rabbits. METHODS A prospective, controlled, comparative intervention study. Six pigmented rabbits (Chinchilla breed) were subjected to intravitreal injection of VEGF165 in their right eye. The left eye was used as control and received an injection of balanced salt solution. In group 1, 3 rabbits received a 10-μg injection, and in group 2, 3 rabbits received a 20-μg injection. At baseline, all subjects were analyzed by anterior biomicroscopy, retinography, fluorescein angiography, and optical coherence tomography (OCT) fundus images. Biomicroscopy and all ancillary examinations were repeated at weeks 1, 2, and 5. In the fifth week after the injection, the rabbits were euthanized and the eyes were enucleated and subjected to histological evaluation. RESULTS Seven days after the intravitreal VEGF165 injection, all rabbits developed intense neovascularization of the retina and anterior segment. Neovascularization of the posterior pole was similar in both groups, and the anterior segment was more florid in group 2. At weeks 1 and 2, neovascularization persisted with a minor decrease in conjunctival hyperemia in both groups. At week 5, there was a partial regression of neovascularization of the posterior pole, which was more prominent in group 1 than group 2, with persistent anterior neovascularization in both groups. OCT showed a statistically significant increase in retinal thickness, hyaloid detachment, and tractional retinal detachment. After the 5-week period, ocular histopathological evaluation showed an increase in retinal thickness, hyaloid detachment, and intense neovascularization in both groups, especially group 2. CONCLUSION This pilot study of a neovascularization model using intravitreal injection of VEGF165 in pigmented rabbits showed that both doses of 10 and 20 μg were successful and effective in inducing vascular growth in the retina and anterior segment and can therefore be used for evaluating drug efficacy in future studies.
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Affiliation(s)
- Emmerson Badaro
- Department of Ophthalmology, Vision Institute (IPEPO), Federal University of São Paulo , São Paulo, Brazil
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Brissova M, Aamodt K, Brahmachary P, Prasad N, Hong JY, Dai C, Mellati M, Shostak A, Poffenberger G, Aramandla R, Levy SE, Powers AC. Islet microenvironment, modulated by vascular endothelial growth factor-A signaling, promotes β cell regeneration. Cell Metab 2014; 19:498-511. [PMID: 24561261 PMCID: PMC4012856 DOI: 10.1016/j.cmet.2014.02.001] [Citation(s) in RCA: 153] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 03/05/2013] [Accepted: 01/27/2014] [Indexed: 12/31/2022]
Abstract
Pancreatic islet endocrine cell and endothelial cell (EC) interactions mediated by vascular endothelial growth factor-A (VEGF-A) signaling are important for islet differentiation and the formation of highly vascularized islets. To dissect how VEGF-A signaling modulates intra-islet vasculature, islet microenvironment, and β cell mass, we transiently increased VEGF-A production by β cells. VEGF-A induction dramatically increased the number of intra-islet ECs but led to β cell loss. After withdrawal of the VEGF-A stimulus, β cell mass, function, and islet structure normalized as a result of a robust, but transient, burst in proliferation of pre-existing β cells. Bone marrow-derived macrophages (MΦs) recruited to the site of β cell injury were crucial for the β cell proliferation, which was independent of pancreatic location and circulating factors such as glucose. Identification of the signals responsible for the proliferation of adult, terminally differentiated β cells will improve strategies aimed at β cell regeneration and expansion.
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Affiliation(s)
- Marcela Brissova
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
| | - Kristie Aamodt
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Priyanka Brahmachary
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Nripesh Prasad
- HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA; Department of Biology, University of Alabama, Huntsville, Huntsville, AL 35899, USA
| | - Ji-Young Hong
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Chunhua Dai
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Mahnaz Mellati
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Alena Shostak
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Greg Poffenberger
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Radhika Aramandla
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Shawn E Levy
- HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA
| | - Alvin C Powers
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN 37232, USA; VA Tennessee Valley Healthcare System, Nashville, TN 37212, USA.
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Reinert RB, Cai Q, Hong JY, Plank JL, Aamodt K, Prasad N, Aramandla R, Dai C, Levy SE, Pozzi A, Labosky PA, Wright CVE, Brissova M, Powers AC. Vascular endothelial growth factor coordinates islet innervation via vascular scaffolding. Development 2014; 141:1480-91. [PMID: 24574008 DOI: 10.1242/dev.098657] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Neurovascular alignment is a common anatomical feature of organs, but the mechanisms leading to this arrangement are incompletely understood. Here, we show that vascular endothelial growth factor (VEGF) signaling profoundly affects both vascularization and innervation of the pancreatic islet. In mature islets, nerves are closely associated with capillaries, but the islet vascularization process during embryonic organogenesis significantly precedes islet innervation. Although a simple neuronal meshwork interconnects the developing islet clusters as they begin to form at E14.5, the substantial ingrowth of nerve fibers into islets occurs postnatally, when islet vascularization is already complete. Using genetic mouse models, we demonstrate that VEGF regulates islet innervation indirectly through its effects on intra-islet endothelial cells. Our data indicate that formation of a VEGF-directed, intra-islet vascular plexus is required for development of islet innervation, and that VEGF-induced islet hypervascularization leads to increased nerve fiber ingrowth. Transcriptome analysis of hypervascularized islets revealed an increased expression of extracellular matrix components and axon guidance molecules, with these transcripts being enriched in the islet-derived endothelial cell population. We propose a mechanism for coordinated neurovascular development within pancreatic islets, in which endocrine cell-derived VEGF directs the patterning of intra-islet capillaries during embryogenesis, forming a scaffold for the postnatal ingrowth of essential autonomic nerve fibers.
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Affiliation(s)
- Rachel B Reinert
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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Davey GC, Patil SB, O'Loughlin A, O'Brien T. Mesenchymal stem cell-based treatment for microvascular and secondary complications of diabetes mellitus. Front Endocrinol (Lausanne) 2014; 5:86. [PMID: 24936198 PMCID: PMC4047679 DOI: 10.3389/fendo.2014.00086] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 05/23/2014] [Indexed: 12/22/2022] Open
Abstract
The worldwide increase in the prevalence of Diabetes mellitus (DM) has highlighted the need for increased research efforts into treatment options for both the disease itself and its associated complications. In recent years, mesenchymal stromal cells (MSCs) have been highlighted as a new emerging regenerative therapy due to their multipotency but also due to their paracrine secretion of angiogenic factors, cytokines, and immunomodulatory substances. This review focuses on the potential use of MSCs as a regenerative medicine in microvascular and secondary complications of DM and will discuss the challenges and future prospects of MSCs as a regenerative therapy in this field. MSCs are believed to have an important role in tissue repair. Evidence in recent years has demonstrated that MSCs have potent immunomodulatory functions resulting in active suppression of various components of the host immune response. MSCs may also have glucose lowering properties providing another attractive and unique feature of this therapeutic approach. Through a combination of the above characteristics, MSCs have been shown to exert beneficial effects in pre-clinical models of diabetic complications prompting initial clinical studies in diabetic wound healing and nephropathy. Challenges that remain in the clinical translation of MSC therapy include issues of MSC heterogeneity, optimal mode of cell delivery, homing of these cells to tissues of interest with high efficiency, clinically meaningful engraftment, and challenges with cell manufacture. An issue of added importance is whether an autologous or allogeneic approach will be used. In summary, MSC administration has significant potential in the treatment of diabetic microvascular and secondary complications but challenges remain in terms of engraftment, persistence, tissue targeting, and cell manufacture.
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Affiliation(s)
- Grace C Davey
- Regenerative Medicine Institute (REMEDI) and Biosciences Building, National University of Ireland , Galway , Ireland
| | - Swapnil B Patil
- Regenerative Medicine Institute (REMEDI) and Biosciences Building, National University of Ireland , Galway , Ireland
| | - Aonghus O'Loughlin
- Department of Medicine, Galway University Hospital (GUH) , Galway , Ireland
| | - Timothy O'Brien
- Regenerative Medicine Institute (REMEDI) and Biosciences Building, National University of Ireland , Galway , Ireland ; Department of Medicine, Galway University Hospital (GUH) , Galway , Ireland
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Hagiwara S, Jha JC, Cooper ME. Identifying and interpreting novel targets that address more than one diabetic complication: a strategy for optimal end organ protection in diabetes. Diabetol Int 2013. [DOI: 10.1007/s13340-013-0148-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Antagonism of PDGF-BB suppresses subretinal neovascularization and enhances the effects of blocking VEGF-A. Angiogenesis 2013; 17:553-62. [PMID: 24154861 DOI: 10.1007/s10456-013-9402-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 10/15/2013] [Indexed: 12/29/2022]
Abstract
Hypoxia-inducible factor-1 (HIF-1) plays an important role in retinal and subretinal neovascularization (NV). Increased levels of HIF-1 cause increased expression of vascular endothelial growth factor (VEGF-A) and current therapies for ocular NV focus on neutralizing VEGF-A, but there is mounting evidence that other HIF-1-responsive gene products may also participate. In this study, we tested the effect of a designed ankyrin repeat protein (DARPin) that selectively binds and antagonizes the hypoxia-regulated gene product PDGF-BB in three models of subretinal NV (relevant to neovascular age-related macular degeneration) and compared its effects to a DARPin that selectively antagonizes VEGF-A. Daily intraperitoneal injections of 10 mg/kg of the anti-PDGF-BB DARPin or 1 mg/kg of the anti-VEGF DARPin significantly suppressed subretinal NV from laser-induced rupture of Bruch's membrane. Injections of 1 mg/kg/day of the anti-PDGF-BB DARPin had no significant effect, but when combined with 1 mg/kg/day of the anti-VEGF-A DARPin there was greater suppression than injection of the anti-VEGF-A DARPin alone. In Vldlr (-/-) mice which spontaneously develop subretinal NV, intraocular injection of 1.85 μg of anti-PDGF-BB or anti-VEGF-A DARPin caused significant suppression of NV and when combined there was greater suppression than with either alone. The two DARPins also showed an additive effect in Tet/opsin/VEGF double transgenic mice, a particularly severe model of subretinal NV and exudative retinal detachment. In addition, intraocular injection of 1.85 μg of anti-PDGF-BB DARPin strongly suppressed ischemia-induced retinal NV, which is relevant to proliferative diabetic retinopathy and retinopathy of prematurity. These data demonstrate that PDGF-BB is another hypoxia-regulated gene product that along with VEGF-A contributes to ocular NV and suppression of both provides an additive effect.
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