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Abstract
OBJECTIVE To investigate the vision loss burden due to vitamin A deficiency (VAD) at the global, regional and national levels by year, age, sex and socio-economic status using prevalence and years lived with disability (YLD). DESIGN International, retrospective, comparative burden-of-disease study. SETTING Prevalence and YLD data were extracted from the Global Burden of Disease (GBD) Study 2017. The association of age-standardised YLD rates and human development index (HDI) was tested by Pearson correlation and linear regression analyses. The Gini coefficient and concentration index (CI) were calculated to demonstrate the trends in between-country inequality in vision loss burden due to VAD. PARTICIPANTS All participants met the GBD inclusion criteria. RESULTS The age-standardised prevalence rate increased by 9·2 %, while the age-standardised YLD rates rose by 10·8 % from 1990 to 2017. Notably, the vision loss burden caused by VAD showed a declining trend since 2014. The vision loss burden was more concentrated in the post-neonatal age group and decreased with increasing age. The age-standardised YLD rates were inversely correlated with HDI (r = -0·2417, P = 0·0084). The CI and Gini coefficients indicated that socio-economic-related and between-country inequality declined from 2000 to 2017. VAD was the eighth leading cause of the age-standardised prevalence rate and ninth leading cause of age-standardised YLD rate among fifteen causes of vision loss in 2017. CONCLUSION VAD has become one of the significant leading causes of vision loss globally. Efforts to control vision impairment related to VAD are needed, especially for children in countries with lower socio-economic status.
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2
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Li X, He S, Zhao M. An Updated Review of the Epigenetic Mechanism Underlying the Pathogenesis of Age-related Macular Degeneration. Aging Dis 2020; 11:1219-1234. [PMID: 33014534 PMCID: PMC7505275 DOI: 10.14336/ad.2019.1126] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 11/26/2019] [Indexed: 12/27/2022] Open
Abstract
Epigenetics has been recognized to play an important role in physiological and pathological processes of the human body. Accumulating evidence has indicated that epigenetic mechanisms contribute to the pathogenesis of age-related macular degeneration (AMD). Although the susceptibility related to genetic variants has been revealed by genome-wide association studies, those genetic variants may predict AMD risk only in certain human populations. Other mechanisms, particularly those involving epigenetic factors, may play an important role in the pathogenesis of AMD. Therefore, we briefly summarize the most recent reports related to such epigenetic mechanisms, including DNA methylation, histone modification, and non-coding RNA, and the interplay of genetic and epigenetic factors in the pathogenesis of AMD.
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Affiliation(s)
- Xiaohua Li
- 1Henan Provincial People's Hospital, Zhengzhou, China.,2Henan Eye Hospital, Henan Eye Institute, Henan Key Laboratory of Ophthalmology and Visual Science, Zhengzhou, China.,3People's Hospital of Zhengzhou University, Zhengzhou, China.,4People's Hospital of Henan University, Zhengzhou, China
| | - Shikun He
- 1Henan Provincial People's Hospital, Zhengzhou, China.,2Henan Eye Hospital, Henan Eye Institute, Henan Key Laboratory of Ophthalmology and Visual Science, Zhengzhou, China.,3People's Hospital of Zhengzhou University, Zhengzhou, China.,4People's Hospital of Henan University, Zhengzhou, China.,5Departments of Pathology and Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA.,6Ophthalmology Optometry Centre, Peking University People's Hospital, Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, Beijing, China
| | - Mingwei Zhao
- 6Ophthalmology Optometry Centre, Peking University People's Hospital, Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, Beijing, China
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3
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Karadag O, Kocamaz M, Dastan M, Ozturk Durur S. Assessment of macular choroidal thickness, central macular thickness and retinal nerve fiber layer in patients receiving oral isotretinoin treatment. Cutan Ocul Toxicol 2020; 39:233-236. [DOI: 10.1080/15569527.2020.1778015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Onur Karadag
- Department of Ophthalmology, Darica Farabi Training and Research Hospital, Kocaeli, Turkey
| | - Murat Kocamaz
- Department of Ophthalmology, Darica Farabi Training and Research Hospital, Kocaeli, Turkey
| | - Metin Dastan
- Department of Ophthalmology, Darica Farabi Training and Research Hospital, Kocaeli, Turkey
| | - Serap Ozturk Durur
- Department of Dermatology, Darica Farabi Training and Research Hospital, Kocaeli, Turkey
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4
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Gemenetzi M, Lotery AJ. Epigenetics in age-related macular degeneration: new discoveries and future perspectives. Cell Mol Life Sci 2020; 77:807-818. [PMID: 31897542 PMCID: PMC7058675 DOI: 10.1007/s00018-019-03421-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 12/04/2019] [Accepted: 12/10/2019] [Indexed: 12/13/2022]
Abstract
The study of epigenetics has explained some of the 'missing heritability' of age-related macular degeneration (AMD). The epigenome also provides a substantial contribution to the organisation of the functional retina. There is emerging evidence of specific epigenetic mechanisms associated with AMD. This 'AMD epigenome' may offer the chance to develop novel AMD treatments.
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Affiliation(s)
- M Gemenetzi
- NIHR Biomedical Research Centre At Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, 162 City Road, London, EC1V 2PD, UK
| | - A J Lotery
- Clinical and Experimental Sciences, Faculty of Medicine, University Hospital Southampton, University of Southampton, South Lab and Path Block, Mailpoint 806, Level D, Southampton, SO16 6YD, UK.
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5
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Zhang D, Deng Z, Tan J, Liu S, Hu S, Tao H, Tang R. All-trans retinoic acid stimulates the secretion of TGF-β2 via the phospholipase C but not the adenylyl cyclase signaling pathway in retinal pigment epithelium cells. BMC Ophthalmol 2019; 19:23. [PMID: 30658598 PMCID: PMC6339369 DOI: 10.1186/s12886-018-1017-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Accepted: 12/21/2018] [Indexed: 12/15/2022] Open
Abstract
Background By investigating that (i) all-trans retinoic acid (ATRA) affects human retinal pigment epithelium (RPE) in expressing and secreting transforming growth factor (TGF)-β2 and (ii) U73122 (phospholipase C inhibitor) and SQ22536 (adenylyl cyclase inhibitor) regulate the ATRA-induced secretion of TGF-β2 in human RPE, we sought to interpret the signaling pathway of ATRA in promoting the development of myopia. Methods The RPE cell line (D407) was treated with (i) ATRA (10 μM), (ii) U73122 (5–40 μM) and ATRA (10 μM), or (iii) SQ22536 (5–40 μM) and ATRA (10 μM). The control group was no-treated. After stimulated at 2, 4, 8, 16, 24, and 48 h, The expression and secretion of TGF-β2 was detected. Results TGF-β2 in the cytoplasm was time-dependent increased by ATRA (p < 0.001). A time-dependent increase in the TGF-β2 protein of the supernatant was induced by ATRA (p < 0.001). U73122 (in the range of 5 to 40 μM) could suppress the secretion of TGF-β2 induced by ATRA (p < 0.001), and 40 μM U73122 could completely inhibit the up-regulated effect of 10 μM ATRA. However, SQ22536 (in the range of 5 to 40 μM) had no impact on the secretion of TGF-β2 induced by ATRA (p > 0.05). Conclusions In RPE cells, ATRA stimulates the secretion of TGF-β2 via the phospholipase C signaling pathway but not the adenylyl cyclase signaling pathway. U73122 may inhibit the promotion of ATRA in the development of myopia.
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Affiliation(s)
- Daren Zhang
- Department of Ophthalmology, The Third Xiangya Hospital, Central South, Changsha, Hunan, China
| | - Zhihong Deng
- Department of Ophthalmology, The Third Xiangya Hospital, Central South, Changsha, Hunan, China.
| | - Jia Tan
- Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, Hunan, China.
| | - Shuirong Liu
- Department of Ophthalmology, The Third Xiangya Hospital, Central South, Changsha, Hunan, China
| | - Shuyu Hu
- Department of Ophthalmology, The Third Xiangya Hospital, Central South, Changsha, Hunan, China
| | - Hui Tao
- Department of Ophthalmology, The Third Xiangya Hospital, Central South, Changsha, Hunan, China
| | - Renhong Tang
- Department of Ophthalmology, The Third Xiangya Hospital, Central South, Changsha, Hunan, China
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6
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Farnoodian M, Sorenson CM, Sheibani N. Negative Regulators of Angiogenesis, Ocular Vascular Homeostasis, and Pathogenesis and Treatment of Exudative AMD. J Ophthalmic Vis Res 2018; 13:470-486. [PMID: 30479719 PMCID: PMC6210860 DOI: 10.4103/jovr.jovr_67_18] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Angiogenesis, the formation of new blood vessels from pre-existing capillaries, is very tightly regulated and normally does not occur except during developmental and reparative processes. This tight regulation is maintained by a balanced production of positive and negative regulators, and alterations under pathological conditions such as retinopathy of prematurity, diabetic retinopathy, and age-related macular degeneration can lead to growth of new and abnormal blood vessels. Although the role of proangiogenic factors such as vascular endothelial growth factor has been extensively studied, little is known about the roles of negative regulators of angiogenesis in the pathogenesis of these diseases. Here, we will discuss the role of thrombospondin-1 (TSP1), one of the first known endogenous inhibitors of angiogenesis, in ocular vascular homeostasis, and how its alterations may contribute to the pathogenesis of age-related macular degeneration and choroidal neovascularization. We will also discuss its potential utility as a therapeutic target for treatment of ocular diseases with a neovascular component.
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Affiliation(s)
- Mitra Farnoodian
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA
| | - Christine M Sorenson
- Department of Pediatrics, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA.,McPherson Eye Research Institute, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA
| | - Nader Sheibani
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA.,McPherson Eye Research Institute, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA.,Department of Biomedical Engineering, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA.,Department of Cell and Regenerative Biology, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA
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7
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Shi Y, Obert E, Rahman B, Rohrer B, Lobo GP. The Retinol Binding Protein Receptor 2 (Rbpr2) is required for Photoreceptor Outer Segment Morphogenesis and Visual Function in Zebrafish. Sci Rep 2017; 7:16207. [PMID: 29176573 PMCID: PMC5701214 DOI: 10.1038/s41598-017-16498-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 11/13/2017] [Indexed: 11/28/2022] Open
Abstract
Vitamin A (all-trans retinol) plays critical roles in mammalian development and vision. Since vitamin A is food-derived, tissue-specific uptake and storage mechanism are needed. In the eye, uptake of RBP4-retinol is mediated by the receptor Stra6, whereas the receptor mediating RBP4 binding and retinol transport into the liver has just recently been discovered. Here we examined the role of zebrafish retinol binding protein receptor 2 (Rbpr2) for RBP4-retinol uptake in developing embryos, using eye development and vision as sensitive readouts. In cultured cells, Rbpr2 localized to membranes and promoted RBP4-retinol uptake. In larvae, Rbpr2 expression was detected in developing intestinal enterocytes and liver hepatocytes. Two rbpr2 mutant zebrafish lines, each resulting in Rbpr2 deficiency, exhibit a small eye defect, and systemic malformations including hydrocephaly and cardiac edema, phenotypes associated with vitamin A deficiency. In the retina, Rbpr2 loss resulted in shorter photoreceptor outer segments, mislocalization and decrease in visual pigments, decreased expression of retinoic acid-responsive genes and photoreceptor cell loss, overall leading to a reduction of visual function. Together, these results demonstrate that Rbpr2-mediated RBP4-retinol uptake in developing liver and intestine is necessary to provide sufficient substrate for ocular retinoid production required for photoreceptor cell maintenance and visual function.
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Affiliation(s)
- Yi Shi
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA.,Tianjin Medical University Eye Hospital, Tianjin, 300384, China
| | - Elisabeth Obert
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Bushra Rahman
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, 29425, USA.,Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC, 2940, USA
| | - Glenn P Lobo
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA. .,Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, 29425, USA.
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8
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Wiseman EM, Bar-El Dadon S, Reifen R. The vicious cycle of vitamin a deficiency: A review. Crit Rev Food Sci Nutr 2017; 57:3703-3714. [DOI: 10.1080/10408398.2016.1160362] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Elina Manusevich Wiseman
- The Center of Nutrigenomics, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Shimrit Bar-El Dadon
- The Center of Nutrigenomics, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Ram Reifen
- The Center of Nutrigenomics, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
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9
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Farnoodian M, Halbach C, Slinger C, Pattnaik BR, Sorenson CM, Sheibani N. High glucose promotes the migration of retinal pigment epithelial cells through increased oxidative stress and PEDF expression. Am J Physiol Cell Physiol 2016; 311:C418-36. [PMID: 27440660 DOI: 10.1152/ajpcell.00001.2016] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 07/18/2016] [Indexed: 12/11/2022]
Abstract
Defects in the outer blood-retinal barrier have significant impact on the pathogenesis of diabetic retinopathy and macular edema. However, the detailed mechanisms involved remain largely unknown. This is, in part, attributed to the lack of suitable animal and cell culture models, including those of mouse origin. We recently reported a method for the culture of retinal pigment epithelial (RPE) cells from wild-type and transgenic mice. The RPE cells are responsible for maintaining the integrity of the outer blood-retinal barrier whose dysfunction during diabetes has a significant impact on vision. Here we determined the impact of high glucose on the function of RPE cells. We showed that high glucose conditions resulted in enhanced migration and increased the level of oxidative stress in RPE cells, but minimally impacted their rate of proliferation and apoptosis. High glucose also minimally affected the cell-matrix and cell-cell interactions of RPE cells. However, the expression of integrins and extracellular matrix proteins including pigment epithelium-derived factor (PEDF) were altered under high glucose conditions. Incubation of RPE cells with the antioxidant N-acetylcysteine under high glucose conditions restored normal migration and PEDF expression. These cells also exhibited increased nuclear localization of the antioxidant transcription factor Nrf2 and ZO-1, reduced levels of β-catenin and phagocytic activity, and minimal effect on production of vascular endothelial growth factor, inflammatory cytokines, and Akt, MAPK, and Src signaling pathways. Thus high glucose conditions promote RPE cell migration through increased oxidative stress and expression of PEDF without a significant effect on the rate of proliferation and apoptosis.
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Affiliation(s)
- Mitra Farnoodian
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Caroline Halbach
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Cassidy Slinger
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Bikash R Pattnaik
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; and
| | - Christine M Sorenson
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; and
| | - Nader Sheibani
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; and Biomedical Engineering, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
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10
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PEDF and its roles in physiological and pathological conditions: implication in diabetic and hypoxia-induced angiogenic diseases. Clin Sci (Lond) 2015; 128:805-23. [PMID: 25881671 PMCID: PMC4557399 DOI: 10.1042/cs20130463] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Pigment epithelium-derived factor (PEDF) is a broadly expressed multifunctional member of the serine proteinase inhibitor (serpin) family. This widely studied protein plays critical roles in many physiological and pathophysiological processes, including neuroprotection, angiogenesis, fibrogenesis and inflammation. The present review summarizes the temporal and spatial distribution patterns of PEDF in a variety of developing and adult organs, and discusses its functions in maintaining physiological homoeostasis. The major focus of the present review is to discuss the implication of PEDF in diabetic and hypoxia-induced angiogenesis, and the pathways mediating PEDF's effects under these conditions. Furthermore, the regulatory mechanisms of PEDF expression, function and degradation are also reviewed. Finally, the therapeutic potential of PEDF as an anti-angiogenic drug is briefly summarized.
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11
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Farnoodian M, Kinter JB, Yadranji Aghdam S, Zaitoun I, Sorenson CM, Sheibani N. Expression of pigment epithelium-derived factor and thrombospondin-1 regulate proliferation and migration of retinal pigment epithelial cells. Physiol Rep 2015; 3:3/1/e12266. [PMID: 25602019 PMCID: PMC4387751 DOI: 10.14814/phy2.12266] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Age‐related macular degeneration (AMD) is the leading cause of vision loss among elderly. Although the pathogenesis of AMD is associated with retinal pigmented epithelium (RPE) dysfunction and abnormal neovascularization the detailed mechanisms remain unresolved. RPE is a specialized monolayer of epithelial cells with important functions in ocular homeostasis. Pathological RPE damage contributes to major ocular conditions including retinal degeneration and irreversible loss of vision in AMD. RPE cells also assist in the maintenance of the ocular angiogenic balance by production of positive and negative regulatory factors including vascular endothelial growth factor (VEGF), thrombospondin‐1 (TSP1), and pigment epithelium‐derived factor (PEDF). The altered production of PEDF and TSP1, as endogenous inhibitors of angiogenesis and inflammation, by RPE cells have been linked to pathogenesis of AMD and choroidal and retinal neovascularization. However, lack of simple methods for isolation and culture of mouse RPE cells has resulted in limited knowledge regarding the cell autonomous role of TSP1 and PEDF in RPE cell function. Here, we describe a method for routine isolation and propagation of RPE cells from wild‐type, TSP1, and PEDF‐deficient mice, and have investigated their impact on RPE cell function. We showed that expression of TSP1 and PEDF significantly impacted RPE cell proliferation, migration, adhesion, oxidative state, and phagocytic activity with minimal effect on their basal rate of apoptosis. Together, our results indicated that the expression of PEDF and TSP1 by RPE cells play crucial roles not only in regulation of ocular vascular homeostasis but also have significant impact on their cellular function. Here, we report the isolation of RPE cells from wild‐type and transgenic mice retina. We demonstrate that lack of thrompospondin‐1 or pigment epithelium‐derived factor impacts the proliferation, migration, adhesion, oxidative state, and phagocytic activity of these cells.
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Affiliation(s)
- Mitra Farnoodian
- Department of Ophthalmology and Visual Sciences, Clinical Investigation Graduate Program, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - James B Kinter
- Department of Ophthalmology and Visual Sciences, Clinical Investigation Graduate Program, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - Saeed Yadranji Aghdam
- Department of Ophthalmology and Visual Sciences, Clinical Investigation Graduate Program, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - Ismail Zaitoun
- Department of Ophthalmology and Visual Sciences, Clinical Investigation Graduate Program, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - Christine M Sorenson
- Department of Pediatrics, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin McPherson Eye Research Institute, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - Nader Sheibani
- Department of Ophthalmology and Visual Sciences, Clinical Investigation Graduate Program, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin McPherson Eye Research Institute, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin Department of Biomedical Engineering, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
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12
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Epigenetic modifications as potential therapeutic targets in age-related macular degeneration and diabetic retinopathy. Drug Discov Today 2014; 19:1387-93. [DOI: 10.1016/j.drudis.2014.03.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 03/12/2014] [Accepted: 03/31/2014] [Indexed: 12/14/2022]
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13
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Masli S, Sheibani N, Cursiefen C, Zieske J. Matricellular protein thrombospondins: influence on ocular angiogenesis, wound healing and immuneregulation. Curr Eye Res 2014; 39:759-74. [PMID: 24559320 PMCID: PMC4278647 DOI: 10.3109/02713683.2013.877936] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Thrombospondins are a family of large multi-domain glycoproteins described as matricelluar proteins based on their ability to interact with a broad range of receptors, matrix molecules, growth factors or proteases, and to modulate array of cellular functions including intracellular signaling, proliferation and migration. Two members of the thrombospondin family, thrombospondin 1 (TSP-1) and thrombospondin 2 (TSP-2) are studied extensively to determine their structure and function. While expressed at low levels in normal adult tissues, their increased expression is seen predominantly in response to cellular perturbations. Despite structural similarities, a notable functional difference between TSP-1 and TSP-2 includes the ability of former to activate of latent TGF-β and its competitive inhibition by the latter. Both these thrombospondins are reported to play important roles in TGF-β rich ocular environment with most reports related to TSP-1. They are expressed by many ocular cell types and detectable in the aqueous and vitreous humor. TSP-1 and TSP-2 influence many cellular interactions in the eye such as angiogenesis, cell migration, wound healing, TGF-β activation and regulation of inflammatory immune responses. Together, these processes are known to contribute to the immune privilege status of the eye. Emerging roles of TSP-1 and TSP-2 in ocular functions and pathology are reviewed here.
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Affiliation(s)
- Sharmila Masli
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, U.S.A
| | - Nader Sheibani
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI, U.S.A
| | | | - James Zieske
- Schepens Eye Research Institute and Massachusetts Eye and Ear, Department of Ophthalmology Harvard Medical School, Boston, MA, U.S.A
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14
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Fernández-Barral A, Orgaz JL, Baquero P, Ali Z, Moreno A, Tiana M, Gómez V, Riveiro-Falkenbach E, Cañadas C, Zazo S, Bertolotto C, Davidson I, Rodríguez-Peralto JL, Palmero I, Rojo F, Jensen LD, del Peso L, Jiménez B. Regulatory and functional connection of microphthalmia-associated transcription factor and anti-metastatic pigment epithelium derived factor in melanoma. Neoplasia 2014; 16:529-42. [PMID: 25030625 PMCID: PMC4198745 DOI: 10.1016/j.neo.2014.06.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Pigment epithelium-derived factor (PEDF), a member of the serine protease inhibitor superfamily, has potent anti-metastatic effects in cutaneous melanoma through its direct actions on endothelial and melanoma cells. Here we show that PEDF expression positively correlates with microphthalmia-associated transcription factor (MITF) in melanoma cell lines and human samples. High PEDF and MITF expression is characteristic of low aggressive melanomas classified according to molecular and pathological criteria, whereas both factors are decreased in senescent melanocytes and naevi. Importantly, MITF silencing down-regulates PEDF expression in melanoma cell lines and primary melanocytes, suggesting that the correlation in the expression reflects a causal relationship. In agreement, analysis of Chromatin immunoprecipitation coupled to high throughput sequencing (ChIP-seq) data sets revealed three MITF binding regions within the first intron of SERPINF1, and reporter assays demonstrated that the binding of MITF to these regions is sufficient to drive transcription. Finally, we demonstrate that exogenous PEDF expression efficiently halts in vitro migration and invasion, as well as in vivo dissemination of melanoma cells induced by MITF silencing. In summary, these results identify PEDF as a novel transcriptional target of MITF and support a relevant functional role for the MITF-PEDF axis in the biology of melanoma.
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Affiliation(s)
- Asunción Fernández-Barral
- Department of Biochemistry, Universidad Autónoma de Madrid, Spain; Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM Madrid, Spain
| | - Jose Luis Orgaz
- Department of Biochemistry, Universidad Autónoma de Madrid, Spain; Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM Madrid, Spain; Randall Division of Cell and Molecular Biophysics, New Hunt's House, Guy's Campus, King's College London, London SE1UL, United Kingdom
| | - Pablo Baquero
- Department of Biochemistry, Universidad Autónoma de Madrid, Spain; Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM Madrid, Spain; Paul O'Gorman Leukaemia Research Centre, Institute of Cancer Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Zaheer Ali
- Division of Cardiovascular Medicine, Department of Medical and Health sciences, Linköping University, Linköping, Sweden
| | - Alberto Moreno
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM Madrid, Spain; Centre for Gene Regulation & Expression, College of Life Sciences, Universtity of Dundee, Dundee DD1 5EH, United Kingdom
| | - María Tiana
- Department of Biochemistry, Universidad Autónoma de Madrid, Spain; Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM Madrid, Spain
| | - Valentí Gómez
- Department of Biochemistry, Universidad Autónoma de Madrid, Spain; Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM Madrid, Spain; Tumor Suppressor Signaling Networks Laboratory, UCL Cancer Institute, University College London, WC1E 6BT, London, United Kingdom
| | - Erica Riveiro-Falkenbach
- Department of Pathology, Hospital Universitario 12 de Octubre, Universidad Complutense, Madrid, Spain; Instituto de Investigación I+12, Madrid, Spain
| | - Carmen Cañadas
- Department of Pathology, Capio-Fundación Jimenez Díaz, Madrid, Spain
| | - Sandra Zazo
- Department of Pathology, Capio-Fundación Jimenez Díaz, Madrid, Spain
| | | | - Irwin Davidson
- Institute de Génétique et de Biologie Moléculaire et Cellulaire, CNRS, INSERM, Université de Strasbourg, Illkirch, France
| | - Jose Luis Rodríguez-Peralto
- Department of Pathology, Hospital Universitario 12 de Octubre, Universidad Complutense, Madrid, Spain; Instituto de Investigación I+12, Madrid, Spain
| | - Ignacio Palmero
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM Madrid, Spain
| | - Federico Rojo
- Department of Pathology, Capio-Fundación Jimenez Díaz, Madrid, Spain
| | - Lasse Dahl Jensen
- Division of Cardiovascular Medicine, Department of Medical and Health sciences, Linköping University, Linköping, Sweden
| | - Luis del Peso
- Department of Biochemistry, Universidad Autónoma de Madrid, Spain; Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM Madrid, Spain
| | - Benilde Jiménez
- Department of Biochemistry, Universidad Autónoma de Madrid, Spain; Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM Madrid, Spain; Instituto de Investigación I+12, Madrid, Spain.
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15
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Amengual J, Zhang N, Kemerer M, Maeda T, Palczewski K, Von Lintig J. STRA6 is critical for cellular vitamin A uptake and homeostasis. Hum Mol Genet 2014; 23:5402-17. [PMID: 24852372 DOI: 10.1093/hmg/ddu258] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Vitamin A must be adequately distributed within the body to maintain the functions of retinoids in the periphery and chromophore production in the eyes. Blood transport of the lipophilic vitamin is mediated by the retinol-binding protein, RBP4. Biochemical evidence suggests that cellular uptake of vitamin A from RBP4 is facilitated by a membrane receptor. This receptor, identified as the Stimulated by retinoic acid gene 6 (Stra6) gene product, is highly expressed in epithelia that constitute blood-tissue barriers. Here we established a Stra6 knockout mouse model to analyze the metabolic basis of vitamin A homeostasis in peripheral tissues. These mice were viable when bred on diets replete in vitamin A, but evidenced markedly reduced levels of ocular retinoids. Ophthalmic imaging and histology revealed malformations in the choroid and retinal pigmented epithelium, early cone photoreceptor cell death, and reduced lengths of rod outer segments. Similar to the blood-retina barrier in the RPE, vitamin A transport through the blood-cerebrospinal fluid barrier in the brain's choroid plexus was impaired. Notably, treatment with pharmacological doses of vitamin A restored vitamin A transport across these barriers and rescued the vision of Stra6(-/-) mice. Furthermore, under conditions mimicking vitamin A excess and deficiency, our analyses revealed that STRA6-mediated vitamin A uptake is a regulated process mandatory for ocular vitamin A uptake when RBP4 constitutes the only transport mode in vitamin A deficiency. These findings identifying STRA6 as a bona fide vitamin A transporter have important implications for disease states associated with impaired blood vitamin A homeostasis.
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Affiliation(s)
| | - Ning Zhang
- Department of Pharmacology, School of Medicine
| | | | - Tadao Maeda
- Department of Pharmacology, School of Medicine, Department of Ophthalmology, School of Medicine
| | - Krzysztof Palczewski
- Department of Pharmacology, School of Medicine, Cleveland Center for Membrane and Structural Biology, Case Western Reserve University, Cleveland, OH 44106, USA
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Craword SE, Fitchev P, Veliceasa D, Volpert OV. The many facets of PEDF in drug discovery and disease: a diamond in the rough or split personality disorder? Expert Opin Drug Discov 2013; 8:769-92. [PMID: 23642051 DOI: 10.1517/17460441.2013.794781] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Pigment epithelium-derived factor (PEDF) was discovered as a neurotrophic factor secreted by retinal pigment epithelial cells. A decade later, it re-emerged as a powerful angiogenesis inhibitor guarding ocular function. Since then, significant advances were made identifying PEDF's mechanisms, targets and biomedical applications. AREAS COVERED The authors review several methodologies that have generated significant new information about the potential of PEDF as a drug. Furthermore, the authors review and discuss mechanistic and structure-function analyses combined with the functional mapping of active fragments, which have yielded several short bioactive PEDF peptides. Additionally, the authors present functional studies in knockout animals and human correlates that have provided important information about conditions amenable to PEDF-based therapies. EXPERT OPINION Through its four known receptors, PEDF causes a wide range of cellular events vitally important for the organism, which include survival and differentiation, migration and invasion, lipid metabolism and stem cell maintenance. These processes are deregulated in multiple pathological conditions, including cancer, metabolic and cardiovascular disease. PEDF has been successfully used in countless preclinical models of these conditions and human correlates suggest a wide utility of PEDF-based drugs. The most significant clinical application of PEDF, to date, is its potential therapeutic use for age-related macular degeneration. Moreover, PEDF-based gene therapy has advanced to early stage clinical trials. PEDF active fragments have been mapped and used to design short peptide mimetics conferring distinct functions of PEDF, which may address specific clinical problems and become prototype drugs.
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Affiliation(s)
- Susan E Craword
- St. Louis University School of Medicine, Department of Pathology, St. Louis, Missouri, USA
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Becerra SP, Notario V. The effects of PEDF on cancer biology: mechanisms of action and therapeutic potential. Nat Rev Cancer 2013; 13:258-71. [PMID: 23486238 PMCID: PMC3707632 DOI: 10.1038/nrc3484] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The potent actions of pigment epithelium-derived factor (PEDF) on tumour-associated cells, and its extracellular localization and secretion, stimulated research on this multifunctional serpin. Such studies have identified several PEDF receptors and downstream signalling pathways. Known cellular PEDF responses have expanded from the initial discovery that PEDF induces retinoblastoma cell differentiation to its anti-angiogenic, antitumorigenic and antimetastatic properties. Although the diversity of PEDF activities seems to be complex, they are consistent with the varied mechanisms that regulate this multimodal factor. If PEDF is to be used for cancer management, a deeper appreciation of its many functions and mechanisms of action is needed.
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Affiliation(s)
- S Patricia Becerra
- National Eye Institute, US National Institutes of Health, Bethesda, Maryland, USA.
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18
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Wang S, Sorenson CM, Sheibani N. Lack of thrombospondin 1 and exacerbation of choroidal neovascularization. ACTA ACUST UNITED AC 2012; 130:615-20. [PMID: 22232368 DOI: 10.1001/archopthalmol.2011.1892] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVES To assess the impact of thrombospondin 1(TSP1) deficiency on choroidal neovascularization (CNV)and to determine whether administration of a TSP1 antiangiogenic mimetic peptide attenuates CNV. METHODS The impact of TSP1 deficiency on laser induced CNV was assessed using wild-type (TSP1 +/+) and TSP1-deficient (TSP1 −/−) mice. Three laser burns were placed in each eye of TSP1 +/+ and TSP1 −/− mice to induce CNV. Intravitreal injection of the TSP1 mimetic peptide was performed on days 1 and 7 postlaser in the mice.For quantitative measurements of neovascularization, intercellular adhesion molecule 2 staining was performed at 14 days postlaser of the choroidal-sclera flat mounts. The recruitment of macrophages to the sites of damage was investigated by immunohistochemistry. The CNV area was measured by intercellular adhesion molecule 2 staining and use of ImageJ software. RESULTS The TSP1 −/− mice exhibited significantly larger areas of neovascularization on choroidal flat mounts compared with TSP1 +/ mice. This was consistent with enhanced recruitment of macrophages in TSP1 −/− mice compared with TSP1 +/+ mice 3 days postlaser. The development of CNV was significantly attenuated in mice receiving the TSP1 antiangiogenic mimetic peptide compared with those receiving vehicle alone. CONCLUSIONS Deficiency of TSP1 contributes to enhanced choroidal neovascularization. This is consistent with the anti-inflammatory and antiangiogenic activity of TSP1. The TSP1 antiangiogenic peptide was effective in attenuation of CNV. CLINICAL RELEVANCE Intravitreal injection of TSP1 antiangiogenic mimetic peptides may provide alternative treatment for CNV.
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Affiliation(s)
- Shoujian Wang
- Department of Ophthalmology and Visual Sciences, University of Wisconsin Medical School, 600 Highland Ave, K6/456 CSC, Madison, WI 53792, USA
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19
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Kawazoe Y, Sugita S, Keino H, Yamada Y, Imai A, Horie S, Mochizuki M. Retinoic acid from retinal pigment epithelium induces T regulatory cells. Exp Eye Res 2011; 94:32-40. [PMID: 22116001 DOI: 10.1016/j.exer.2011.11.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 11/08/2011] [Accepted: 11/09/2011] [Indexed: 01/15/2023]
Abstract
Primary cultured retinal pigment epithelial (RPE) cells can convert T cells into T regulatory cells (Tregs) through inhibitory factor(s) including transforming growth factor β (TGFβ) in vitro. Retinoic acid (RA) enhances induction of CD4(+) Tregs in the presence of TGFβ. We investigated whether RA produced by RPE cells can promote generation of Tregs. We found that in vitro, RA-treated T cells expressed high levels of Foxp3 in the presence of recombinant TGFβ. In GeneChip analysis, cultured RPE cells constitutively expressed RA-associated molecules such as RA-binding proteins, enzymes, and receptors. RPE from normal mice, but not vitamin A-deficient mice, contained significant levels of TGFβ. RPE-induced Tregs from vitamin A-deficient mice failed to suppress activation of target T cells. Only a few Foxp3(+) T cells were found in intraocular cells from vitamin A-deficient experimental autoimmune uveitis (EAU) mice, whereas expression was higher in cells from normal EAU mice. RA receptor antagonist-pretreated or RA-binding protein-siRNA-transfected RPE cells failed to convert CD4(+) T cells into Tregs. Our data support the hypothesis that RPE cells produce RA, thereby enabling bystander T cells to be converted into Tregs through TGFβ promotion, which can then participate in the establishment of immune tolerance in the eye.
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Affiliation(s)
- Yuko Kawazoe
- Department of Ophthalmology & Visual Science, Tokyo Medical and Dental University Graduate School of Medicine, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
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20
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Schmitz JC, Protiva P, Gattu AK, Utsumi T, Iwakiri Y, Neto AG, Quinn M, Cornwell ML, Fitchev P, Lugea A, Crawford SE, Chung C. Pigment epithelium-derived factor regulates early pancreatic fibrotic responses and suppresses the profibrotic cytokine thrombospondin-1. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 179:2990-9. [PMID: 21964188 DOI: 10.1016/j.ajpath.2011.08.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 08/01/2011] [Accepted: 08/10/2011] [Indexed: 01/09/2023]
Abstract
Pigment epithelium-derived factor (PEDF) is important for maintaining the normal extracellular matrix. We hypothesized that the initiation of pancreatic fibrosis is dependent on the loss of PEDF. Pancreatic PEDF expression was assessed in wild-type mice fed either a control or ethanol diet using an intragastric feeding model. Pancreatitis responses were elicited with either a single episode or a repetitive cerulein-induced (50 μg/kg, 6 hourly i.p. injections) protocol in wild-type and PEDF-null mice. Quantitative real-time PCR and immunoblotting were performed to assess fibrogenic responses. In wild-type animals, PEDF expression increased with pancreatitis and was more pronounced in mice fed ethanol. Compared with wild-type mice, α-smooth muscle actin staining and expression levels of fibrogenic markers (eg, transforming growth factor-β1, platelet-derived growth factor, collagen I, and thrombospondin-1) were higher in PEDF-null mice at baseline. Sirius red staining revealed more fibrosis in PEDF-null versus wild-type pancreas 1 week after pancreatitis. Differences in tissue fibrosis resolved with longer recovery periods. PEDF overexpression suppressed thrombospondin-1 levels in vitro. Ethanol feeding and experimental pancreatitis increased PEDF expression in wild-type mice. PEDF-null mice, however, demonstrated enhanced early fibrotic responses compared with wild-type mice with pancreatitis. These findings indicate that PEDF acts as a compensatory antifibrotic cytokine in pancreatitis.
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Affiliation(s)
- John C Schmitz
- Section of Digestive Diseases, VA Connecticut Healthcare System, New Haven, Connecticut, USA
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21
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Doyon G, St-Jean S, Darsigny M, Asselin C, Boudreau F. Nuclear receptor co-repressor is required to maintain proliferation of normal intestinal epithelial cells in culture and down-modulates the expression of pigment epithelium-derived factor. J Biol Chem 2009; 284:25220-9. [PMID: 19608741 DOI: 10.1074/jbc.m109.022632] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Stem cells of the gut epithelium constantly produce precursors that progressively undergo a succession of molecular changes resulting in growth arrest and commitment to a specific differentiation program. Few transcriptional repressors have been identified that maintain the normal intestinal epithelial cell (IEC) proliferation state. Herein, we show that the nuclear receptor co-repressor (NCoR1) is differentially expressed during the proliferation-to-differentiation IEC transition. Silencing of NCoR1 expression in proliferating cells of crypt origin resulted in a rapid growth arrest without associated cell death. A genechip profiling analysis identified several candidate genes to be up-regulated in NCoR1-deficient IEC. Pigment epithelium-derived factor (PEDF, also known as serpinf1), a suspected tumor suppressor gene that plays a key role in the inhibition of epithelial tissue growth, was significantly up-regulated in these cells. Chromatin immunoprecipitation experiments showed that the PEDF gene promoter was occupied by NCoR1 in proliferating epithelial cells. Multiple retinoid X receptor (RXR) heterodimers interacting sites of the PEDF promoter were confirmed to interact with RXR and retinoid acid receptor (RAR). Cotransfection assays showed that RXR and RAR were able to transactivate the PEDF promoter and that NCoR1 was repressing this effect. Finally, forced expression of PEDF in IEC resulted in a slower rate of proliferation. These observations suggest that NCoR1 expression is required to maintain IEC in a proliferative state and identify PEDF as a novel transcriptional target for NCoR1 repressive action.
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Affiliation(s)
- Geneviève Doyon
- Département d'Anatomie et Biologie Cellulaire, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
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22
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Wang S, Gottlieb JL, Sorenson CM, Sheibani N. Modulation of thrombospondin 1 and pigment epithelium-derived factor levels in vitreous fluid of patients with diabetes. ACTA ACUST UNITED AC 2009; 127:507-13. [PMID: 19365032 DOI: 10.1001/archophthalmol.2009.53] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVE To determine the levels of 2 endogenous inhibitors of angiogenesis, thrombospondin 1 (TSP-1) and pigment epithelium-derived factor (PEDF), in the vitreous fluid from patients with and without diabetes. METHODS The levels of TSP-1 and PEDF in vitreous samples from diabetic and age-matched nondiabetic patients were determined by Western blot analysis. RESULTS We observed significant amounts of TSP-1 and PEDF in the vitreous samples of control eyes. The TSP-1 levels varied in samples from patients with diabetes. In contrast, PEDF levels showed little or no change in vitreous samples from patients with or without diabetes. However, the PEDF protein exhibited variation in its molecular weight among the samples. We consistently observed lower levels of TSP-1 in diabetic patients who expressed the higher-molecular-weight PEDF isoform. CONCLUSIONS In diabetes, changes in the TSP-1 level may play a role in shifting the angiogenic balance and contributing to the pathogenesis of diabetic retinopathy. Although the PEDF level did not change, the diabetic samples with the higher-molecular-weight PEDF isoform consistently showed lower levels of TSP-1. CLINICAL RELEVANCE The presence of the higher-molecular-weight PEDF isoform may be associated with greater risk of severe diabetic retinopathy.
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Affiliation(s)
- Shoujian Wang
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, 600 Highland Ave, K6/458 CSC, Madison, WI 53792-4673, USA
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Yu K, Ge J, Summers JB, Li F, Liu X, Ma P, Kaminski J, Zhuang J. TSP-1 secreted by bone marrow stromal cells contributes to retinal ganglion cell neurite outgrowth and survival. PLoS One 2008; 3:e2470. [PMID: 18575624 PMCID: PMC2430538 DOI: 10.1371/journal.pone.0002470] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2007] [Accepted: 05/16/2008] [Indexed: 01/30/2023] Open
Abstract
Background Bone marrow stromal cells (BMSCs) are pluripotent and thereby a potential candidate for cell replacement therapy for central nervous system degenerative disorders and traumatic injury. However, the mechanism of their differentiation and effect on neural tissues has not been fully elucidated. This study evaluates the effect of BMSCs on neural cell growth and survival in a retinal ganglion cell (RGCs) model by assessing the effect of changes in the expression of a BMSC-secreted protein, thrombospondin-1 (TSP-1), as a putative mechanistic agent acting on RGCs. Methods and Findings The effect of co-culturing BMSCs and RGCs in vitro was evaluated by measuring the following parameters: neurite outgrowth, RGC survival, BMSC neural-like differentiation, and the effect of TSP-1 on both cell lines under basal secretion conditions and when TSP-1 expression was inhibited. Our data show that BMSCs improved RGC survival and neurite outgrowth. Synaptophysin, MAP-2, and TGF-β expression are up-regulated in RGCs co-cultured with BMSCs. Interestingly, the BMSCs progressively displayed neural-like morphology over the seven-day study period. Restriction display polymerase chain reaction (RD-PCR) was performed to screen for differentially expressed genes in BMSCs cultured alone or co-cultured with RGCs. TSP-1, a multifactorial extracellular matrix protein, is critically important in the formation of neural connections during development, so its function in our co-culture model was investigated by small interfering RNA (siRNA) transfection. When TSP-1 expression was decreased with siRNA silencing, BMSCs had no impact on RGC survival, but reduced neurite outgrowth and decreased expression of synaptophysin, MAP-2 and TGF-β in RGCs. Furthermore, the number of BMSCs with neural-like characteristics was significantly decreased by more than two-fold using siRNA silencing. Conclusions Our data suggest that the TSP-1 signaling pathway might have an important role in neural-like differentiation in BMSCs and neurite outgrowth in RGCs. This study provides new insights into the potential reparative mechanisms of neural cell repair.
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Affiliation(s)
- Keming Yu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People's Republic of China
| | - Jian Ge
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People's Republic of China
| | - James Bradley Summers
- Department of Radiology, University of South Alabama, Mobile, Alabama, United States of America
| | - Fan Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People's Republic of China
| | - Xuan Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People's Republic of China
| | - Ping Ma
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People's Republic of China
| | - Joseph Kaminski
- Department of Radiology, Medical College of Georgia, Augusta, Georgia, United States of America
- * E-mail: (JK); (JZ)
| | - Jing Zhuang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People's Republic of China
- * E-mail: (JK); (JZ)
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Uchida H, Kuroki M, Shitama T, Hayashi H, Kuroki M. Activation of TGF-beta1 through up-regulation of TSP-1 by retinoic acid in retinal pigment epithelial cells. Curr Eye Res 2008; 33:199-203. [PMID: 18293192 DOI: 10.1080/02713680701852090] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE Retinoic acid (RA) affects the activation of transforming growth factor-beta 1 (TGF-beta1) in a variety of cells. We have previously shown that thrombospondin-1 (TSP-1) expression in retinal pigment epithelial (RPE) cells is up-regulated by RA. Since TSP-1 activates TGF-beta1, we investigated whether RA stimulates the activation of TGF-beta1 through up-regulation of TSP-1 in RPE cells. METHODS Human RPE cells were cultured with RA or TSP-1. The active form of TGF-beta1 in the culture medium was measured by enzyme-linked immunosorbent assay. RESULTS The active form of TGF-beta1 was increased dose-dependently by RA or TSP-1. The activation of TGF-beta1 by RA was significantly hampered by an anti-TSP-1 antibody. Also, antibodies against integrins alphavbeta3 and alphavbeta5 inhibited the activation of TGF-beta1. CONCLUSIONS These findings suggest that, in RPE cells, RA increases the activation of TGF-beta1 via up-regulation of TSP-1, and integrins such as alphavbeta3 and alphavbeta5 are essential in this activation step.
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Affiliation(s)
- Hiroko Uchida
- Department of Ophthalmology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan.
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25
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Heimsath EG, Unda R, Vidro E, Muniz A, Villazana-Espinoza ET, Tsin A. ARPE-19 cell growth and cell functions in euglycemic culture media. Curr Eye Res 2007; 31:1073-80. [PMID: 17169846 DOI: 10.1080/02713680601052320] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Human retinal pigmented epithelial cells (ARPE-19) grown in euglycemic media (5.5 mM) had lower cell number, significantly different cell morphology, and lower levels of vascular endothelial growth factor (VEGF) in the culture media than those grown in hyperglycemic media (18 mM) customarily used for culturing ARPE-19 cells. Although it has been shown that within a 24-hour period, all-trans retinoic acid significantly reduces VEGF secretion by retinal pigmented epithelial cells (grown in 18 mM glucose), such an inhibitory effect was not observed in cells grown in 5.5 mM glucose. Our results suggest that ARPE-19 cells grown in euglycemic media exhibit distinctly different cell growth, cell differentiation, and cell functions in comparison to cells grown in hyperglycemic media. Because euglycemic conditions provide a physiological glucose environment, this glucose concentration must be included in all future investigations of the mechanism of diabetic retinopathy when studying VEGF secretion by ARPE-19 cells.
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Zhang SX, Ma JX. Ocular neovascularization: Implication of endogenous angiogenic inhibitors and potential therapy. Prog Retin Eye Res 2007; 26:1-37. [PMID: 17074526 DOI: 10.1016/j.preteyeres.2006.09.002] [Citation(s) in RCA: 148] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Ocular neovascularization (NV) is the primary cause of blindness in a wide range of ocular diseases, such as diabetic retinopathy (DR) and age-related macular degeneration (AMD). The exact mechanism underlying the pathogenesis of ocular NV is not yet well understood, and as a consequence, there is no satisfactory therapy for ocular NV. In the last 10 years, a number of studies provided increasing evidence demonstrating that the imbalance between angiogenic stimulating factors and angiogenic inhibitors is a major contributor to the angiogenesis induced by various insults, such as hypoxia or ischemia, inflammation and tumor. The angiogenic inhibitors alone or in combination with other existing therapies are, therefore, believed to be promising in the treatment of ocular NV in the near future. This article reviews recent progress in studies on the mechanisms and treatment of ocular NV, focusing on the implication and therapeutic potential of endogenous angiogenic inhibitors in ocular NV.
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Affiliation(s)
- Sarah X Zhang
- Department of Medicine Endocrinology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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27
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Lim JI, Walonker AF, Levin L, Mahmoud M, Sadda S, Flaxel CJ, Humayun M, deJuan E, Labree L. ONE-YEAR RESULTS OF A PILOT STUDY USING ORAL 13-CIS RETINOIC ACID AS A TREATMENT FOR SUBFOVEAL PREDOMINANTLY OCCULT CHOROIDAL NEOVASCULARIZATION IN PATIENTS WITH AGE-RELATED MACULAR DEGENERATION. Retina 2006; 26:314-21. [PMID: 16508432 DOI: 10.1097/00006982-200603000-00010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To evaluate the safety and evidence of efficacy for oral 13-cis retinoic acid as a treatment for patients with subfoveal occult choroidal neovascularization (CNV) due to age-related macular degeneration (ARMD). METHODS Patients with active, subfoveal occult CNV with no prior treatment of the subfoveal component were eligible for inclusion. Patients received 40 mg of 13-cis retinoic acid twice daily for 5 months, stopped treatment for 2 months, and then resumed treatment for 5 months. Patients were observed monthly with Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity (VA), clinical examination, fluorescein angiography, and laboratory testing. RESULTS Eleven patients, aged 64 to 88 years, were enrolled and followed for 1 year. Initial VA ranged from 55 (20/40) to 5 (20/400) ETDRS letters (median 48 letters). Mild drug-related side effects (dry skin, chapped lips) occurred in all 11 patients. Three patients experienced more severe side effects (muscle aches, mood swings) and did not resume treatment after the drug holiday. Moderate VA loss occurred in 36% at both 6 and 12 months. CONCLUSIONS Oral 13-cis retinoic acid is too toxic to be useful in patients with ARMD. Oral 13-cis retinoic acid did not improve vision although it may have slowed visual acuity loss in patients with ARMD with occult subfoveal CNV.
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Affiliation(s)
- Jennifer I Lim
- Doheny Retina Institute of the Doheny Eye Institute, Los Angeles, CA, USA.
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Uno K, Bhutto IA, McLeod DS, Merges C, Lutty GA. Impaired expression of thrombospondin-1 in eyes with age related macular degeneration. Br J Ophthalmol 2006; 90:48-54. [PMID: 16361667 PMCID: PMC1856899 DOI: 10.1136/bjo.2005.074005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
AIMS This study investigated the expression and localisation of thrombospondin-1 (TSP-1), a known anti-angiogenic extracellular matrix protein, in normal aged control human eyes and eyes with age related macular degeneration (AMD). METHODS Immunohistochemical analysis with mouse anti-human TSP-1 antibody and mouse anti-human CD 34 antibody, as a blood vessel marker, was performed on frozen sections from macular and peripheral blocks of aged control donor eyes (n = 12; mean age 78.8 years), and eyes with AMD (n = 12; mean age 83.9 years). Pigment in retinal pigment epithelium (RPE) and choroidal melanocytes was bleached. Three independent observers scored the immunohistochemical reaction product. RESULTS In the macular region, TSP-1 expression was observed intensely in Bruch's membrane and weakly in RPE basement membrane, choriocapillaris, and the wall of large choroidal blood vessels in the aged control eyes. In eyes with AMD, TSP-1 immunoreactivity was significantly lower in all structures except RPE basement membrane (p<0.01). There was significantly lower TSP-1 in the far periphery than the equator and submacular regions in all eyes. TSP-1 immunoreactivity was low in choroidal neovascularisation (CNV), but it was high and diffuse in adjacent scar tissue. CONCLUSION These findings suggest that decreased TSP-1 in Bruch's membrane and choroidal vessels during AMD may permit the formation of CNV.
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Affiliation(s)
- K Uno
- Ophthalmological Institute, Johns Hopkins Hospital, Baltimore, MD 21287-9115, USA
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Hiscott P, Paraoan L, Choudhary A, Ordonez JL, Al-Khaier A, Armstrong DJ. Thrombospondin 1, thrombospondin 2 and the eye. Prog Retin Eye Res 2006; 25:1-18. [PMID: 15996506 DOI: 10.1016/j.preteyeres.2005.05.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Thrombospondin 1 and thrombospondin 2 (TSP1 and TSP2), which comprise the subgroup A thrombospondins, are matricellular proteins. As matricellular proteins, they modulate interactions between cells and the cellular environment, regulate cell adhesion and typically are expressed during tissue formative processes. In general, TSP1 and TSP2 counter angiogenesis (including tumour angiogenesis) and play important but contrasting roles during cutaneous repair. The two proteins are involved in development, including that of the eye, although evidence suggests that they have their greatest impact during tissue production in the adult. In the normal adult eye, they tend to be found at sites of ongoing matrix synthesis or cell-matrix interactions. At these sites, the two proteins possibly influence cellular differentiation and/or basement membrane deposition. TSP1 is also present in the intraocular fluids and drainage pathway, where it may function in maintaining the anti-angiogenic environment and in intraocular pressure control, respectively. TSP1 could also be involved in ocular immune privilege. Unlike in skin wounds, where TSP1 is derived from the blood and is present only in the early phases of repair, ocular tissue damage appears to lead to protacted TSP1 synthesis by local cells. This response might help suppress angiogenesis in the transparent tissues of the eye and so lessen visual axis opacification following injury. However, TSP2, which is also produced by damaged ophthalmic tissue and may be especially important in matrix organisation, seems to augment contraction in anomalous intraocular fibrosis. Elucidating the roles of TSP1 and TSP2 in ocular physiology and pathobiology may lead to improved therapies for neovascular, neoplastic, reparative and other ophthalmic diseases.
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Affiliation(s)
- Paul Hiscott
- Unit of Ophthalmology, School of Clinical Science, University Clinical Departments, The Duncan Building, University of Liverpool, Daulby Street, Liverpool L69 3GA, UK.
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