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Cell transdifferentiation in ocular disease: Potential role for connexin channels. Exp Cell Res 2021; 407:112823. [PMID: 34506760 DOI: 10.1016/j.yexcr.2021.112823] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/02/2021] [Accepted: 09/05/2021] [Indexed: 11/22/2022]
Abstract
Cell transdifferentiation is the conversion of a cell type to another without requiring passage through a pluripotent cell state, and encompasses epithelial- and endothelial-mesenchymal transition (EMT and EndMT). EMT and EndMT are well defined processes characterized by a loss of epithelial/endothelial phenotype and gain in mesenchymal spindle shaped morphology, which results in increased cell migration and decreased apoptosis and cellular senescence. Such cells often develop invasive properties. Physiologically, these processes may occur during embryonic development and can resurface, for example, to promote wound healing in later life. However, they can also be a pathological process. In the eye, EMT, EndMT and cell transdifferentiation have all been implicated in development, homeostasis, and multiple diseases affecting different parts of the eye. Connexins, constituents of connexin hemichannels and intercellular gap junctions, have been implicated in many of these processes. In this review, we firstly provide an overview of the molecular mechanisms induced by transdifferentiation (including EMT and EndMT) and its involvement in eye diseases. We then review the literature for the role of connexins in transdifferentiation in the eye and eye diseases. The evidence presented in this review supports the need for more studies into the therapeutic potential for connexin modulators in prevention and treatment of transdifferentiation related eye diseases, but does indicate that connexin channel modulation may be an upstream and unifying approach for regulating these otherwise complex processes.
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Krishna L, Dhamodaran K, Subramani M, Ponnulagu M, Jeyabalan N, Krishna Meka SR, Jayadev C, Shetty R, Chatterjee K, Khora SS, Das D. Protective Role of Decellularized Human Amniotic Membrane from Oxidative Stress-Induced Damage on Retinal Pigment Epithelial Cells. ACS Biomater Sci Eng 2018; 5:357-372. [DOI: 10.1021/acsbiomaterials.8b00769] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Lekshmi Krishna
- Stem Cell Research Lab, GROW Laboratories, Narayana Nethralaya Foundation, 258/A, Bommasandra Industrial Area, Bangalore, Karnataka, India
- School of Bioscience and Technology, VIT University, Vellore, Tamil Nadu, India
| | - Kamesh Dhamodaran
- Stem Cell Research Lab, GROW Laboratories, Narayana Nethralaya Foundation, 258/A, Bommasandra Industrial Area, Bangalore, Karnataka, India
| | - Murali Subramani
- Stem Cell Research Lab, GROW Laboratories, Narayana Nethralaya Foundation, 258/A, Bommasandra Industrial Area, Bangalore, Karnataka, India
| | - Murugeswari Ponnulagu
- Stem Cell Research Lab, GROW Laboratories, Narayana Nethralaya Foundation, 258/A, Bommasandra Industrial Area, Bangalore, Karnataka, India
| | - Nallathambi Jeyabalan
- Grow Laboratories, Narayana Nethralaya Foundation, 258/A, Bommasandra Industrial Area, Bangalore, Karnataka, India
| | - Sai Rama Krishna Meka
- Department of Materials Engineering, Indian Institute of Science, Bangalore, Karnataka, India
| | - Chaitra Jayadev
- Department of Vitreo-retinal Services, Narayana Nethralaya Eye Institute, 258/A, Bommasandra Industrial Area, Bangalore, Karnataka, India
| | - Rohit Shetty
- Department of Cornea and Refractive Surgery, Narayana Nethralaya Eye Institute, 258/A, Bommasandra Industrial Area, Bangalore, Karnataka, India
| | - Kaushik Chatterjee
- Department of Materials Engineering, Indian Institute of Science, Bangalore, Karnataka, India
| | | | - Debashish Das
- Stem Cell Research Lab, GROW Laboratories, Narayana Nethralaya Foundation, 258/A, Bommasandra Industrial Area, Bangalore, Karnataka, India
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3
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Intracellular oligonucleotide delivery using the cell penetrating peptide Xentry. Sci Rep 2018; 8:11256. [PMID: 30050146 PMCID: PMC6062516 DOI: 10.1038/s41598-018-29556-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 07/13/2018] [Indexed: 11/21/2022] Open
Abstract
The current study investigated the use of two cationic peptides, Xentry-KALA (XK) and Xentry-Protamine (XP), for intracellular delivery of Connexin43 antisense oligonucleotides (Cx43AsODN). The charge and size of Cx43AsODN:XK and Cx43AsODN:XP complexes was determined by Zetasizer analysis. The earliest positive zeta potential reading was obtained at a 1:2 and 1:1.2 charge ratio of Cx43AsODN:XK and Cx43AsODN:XP respectively, with Cx43AsODN:XK resulting in overall larger complexes than Cx43AsODN:XP. Gel shift mobility assays revealed complete complex formation at a 1:2.5 and 1:2.2 charge ratio of Cx43AsODN:XK and Cx43AsODN:XP, respectively. Cellular uptake studies were carried out in ARPE-19 cells. While both complexes were able to enter the cells, Cx43AsODN:XK uptake appeared punctate and circular indicative of endosomal containment. Cx43AsODN:XP uptake, in contrast, resulted in diffuse appearance inside the cell suggesting endosomal escape of the cargo. Finally, western blot analysis confirmed that Cx43AsODN:XP was able to knockdown Cx43 expression in these cells under normal and hypoxic conditions.
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Expression and function of connexin 43 protein in mouse and human retinal pigment epithelial cells as hemichannels and gap junction proteins. Exp Eye Res 2018; 168:128-137. [DOI: 10.1016/j.exer.2018.01.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 01/18/2018] [Accepted: 01/18/2018] [Indexed: 01/08/2023]
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Penberthy KK, Rival C, Shankman LS, Raymond MH, Zhang J, Perry JSA, Lee CS, Han CZ, Onengut-Gumuscu S, Palczewski K, Lysiak JJ, Ravichandran KS. Context-dependent compensation among phosphatidylserine-recognition receptors. Sci Rep 2017; 7:14623. [PMID: 29116131 PMCID: PMC5676788 DOI: 10.1038/s41598-017-15191-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 10/19/2017] [Indexed: 12/03/2022] Open
Abstract
Phagocytes express multiple phosphatidylserine (PtdSer) receptors that recognize apoptotic cells. It is unknown whether these receptors are interchangeable or if they play unique roles during cell clearance. Loss of the PtdSer receptor Mertk is associated with apoptotic corpse accumulation in the testes and degeneration of photoreceptors in the eye. Both phenotypes are linked to impaired phagocytosis by specialized phagocytes: Sertoli cells and the retinal pigmented epithelium (RPE). Here, we overexpressed the PtdSer receptor BAI1 in mice lacking MerTK (Mertk -/- Bai1 Tg ) to evaluate PtdSer receptor compensation in vivo. While Bai1 overexpression rescues clearance of apoptotic germ cells in the testes of Mertk -/- mice it fails to enhance RPE phagocytosis or prevent photoreceptor degeneration. To determine why MerTK is critical to RPE function, we examined visual cycle intermediates and performed unbiased RNAseq analysis of RPE from Mertk +/+ and Mertk -/- mice. Prior to the onset of photoreceptor degeneration, Mertk -/- mice had less accumulation of retinyl esters and dysregulation of a striking array of genes, including genes related to phagocytosis, metabolism, and retinal disease in humans. Collectively, these experiments establish that not all phagocytic receptors are functionally equal, and that compensation among specific engulfment receptors is context and tissue dependent.
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Affiliation(s)
- Kristen K Penberthy
- Center for Cell Clearance, University of Virginia, Charlottesville, VA, USA
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Claudia Rival
- Center for Cell Clearance, University of Virginia, Charlottesville, VA, USA
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA, USA
- Department of Urology, University of Virginia, Charlottesville, VA, USA
| | - Laura S Shankman
- Center for Cell Clearance, University of Virginia, Charlottesville, VA, USA
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Michael H Raymond
- Center for Cell Clearance, University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Jianye Zhang
- Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Justin S A Perry
- Center for Cell Clearance, University of Virginia, Charlottesville, VA, USA
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Chang Sup Lee
- Center for Cell Clearance, University of Virginia, Charlottesville, VA, USA
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA, USA
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Gyeongsang National University, 501 Jinju-daero, Jinju, Gyeongnam, 52828, Korea
| | - Claudia Z Han
- Center for Cell Clearance, University of Virginia, Charlottesville, VA, USA
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Suna Onengut-Gumuscu
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - Krzysztof Palczewski
- Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Jeffrey J Lysiak
- Center for Cell Clearance, University of Virginia, Charlottesville, VA, USA
- Department of Urology, University of Virginia, Charlottesville, VA, USA
| | - Kodi S Ravichandran
- Center for Cell Clearance, University of Virginia, Charlottesville, VA, USA.
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA, USA.
- Inflammation Research Center, VIB, and the Department of Biomedical molecular Biology, Ghent University, Ghent, Belgium.
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Shafei EV, Kurinov AM, Kuznetsova AV, Aleksandrova MA. Reprogramming of Human Retinal Pigment Epithelial Cells under the Effect of bFGF In Vitro. Bull Exp Biol Med 2017; 163:574-582. [PMID: 28853082 DOI: 10.1007/s10517-017-3852-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Indexed: 01/08/2023]
Abstract
We studied the effect of bFGF on human retinal pigment epithelial cells in vitro In ARPE-19 cells, enhanced expression of KLF4 mRNA and reduced expression of PAX6, MITF, and OTX2 mRNA specific for retinal pigment epithelium were observed after bFGF application. The expression of KLF4 mRNA peaked in 72 h after bFGF application and then sharply decreased, which was accompanied by a 3-fold increase in TUBB3 mRNA expression (neuronal marker). Immunocytochemical analysis showed that in the presence of bFGF, some cells retained epithelial properties and showed positive staining for connexin-43, while others had long axon-like processes and demonstrated positive staining for βIII-tubulin, which attests to their neuronal transdifferentiation. Despite the prevalence of the epithelial properties, ARPE-19 cells under the influence of bFGF can show proneuronal properties.
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Affiliation(s)
- E V Shafei
- N. K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - A M Kurinov
- N. K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - A V Kuznetsova
- N. K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - M A Aleksandrova
- N. K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia.
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Roy S, Kim D, Lim R. Cell-cell communication in diabetic retinopathy. Vision Res 2017; 139:115-122. [PMID: 28583293 DOI: 10.1016/j.visres.2017.04.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 04/27/2017] [Accepted: 04/28/2017] [Indexed: 10/19/2022]
Abstract
In diabetic retinopathy, high glucose (HG)-mediated breakdown in cell-cell communication promotes disruption of retinal homeostasis. Several studies indicate that HG condition alters expression of connexin genes and subsequent gap junction intercellular communication (GJIC) in retinal vascular cells and non-vascular cells. A serious consequence of disrupted cell-cell communication is apoptosis and breakdown of the blood-retinal barrier (BRB). More recently, studies suggest adverse effects from HG on retinal Müller cells. This article focuses on HG-mediated changes in connexin expression and GJIC and their subsequent effects on the breakdown of retinal homeostasis, cell death, compromised vascular permeability, and interactions between endothelial cells, pericytes and retinal Müller cells in the pathogenesis of diabetic retinopathy. Additionally, options for rectifying disrupted homeostasis under HG condition associated with diabetic retinopathy are reviewed.
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Affiliation(s)
- Sayon Roy
- Department of Medicine and Ophthalmology, Boston University School of Medicine, Boston, MA, United States.
| | - Dongjoon Kim
- Department of Medicine and Ophthalmology, Boston University School of Medicine, Boston, MA, United States
| | - Remington Lim
- Department of Medicine and Ophthalmology, Boston University School of Medicine, Boston, MA, United States
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Cechmanek PB, McFarlane S. Retinal pigment epithelium expansion around the neural retina occurs in two separate phases with distinct mechanisms. Dev Dyn 2017; 246:598-609. [PMID: 28556369 DOI: 10.1002/dvdy.24525] [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: 09/02/2016] [Revised: 01/17/2017] [Accepted: 05/10/2017] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND The retinal pigment epithelium (RPE) is a specialized monolayer of epithelial cells that forms a tight barrier surrounding the neural retina. RPE cells are indispensable for mature photoreceptor renewal and survival, yet how the initial RPE cell population expands around the neural retina during eye development is poorly understood. RESULTS Here we characterize the differentiation, proliferation, and movements of RPE progenitors in the Zebrafish embryo over the period of optic cup morphogenesis. RPE progenitors are present in the dorsomedial eye vesicle shortly after eye vesicle evagination. We define two separate phases that allow for full RPE expansion. The first phase involves a previously uncharacterized antero-wards expansion of the RPE progenitor domain in the inner eye vesicle leaflet, driven largely by an increase in cell number. During this phase, RPE progenitors start to express differentiation markers. In the second phase, the progenitor domain stretches in the dorsoventral and posterior axes, involving cell movements and shape changes, and coinciding with optic cup morphogenesis. Significantly, cell division is not required for RPE expansion. CONCLUSIONS RPE development to produce the monolayer epithelium that covers the back of the neural retina occurs in two distinct phases driven by distinct mechanisms. Developmental Dynamics 246:598-609, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Paula Bernice Cechmanek
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Sarah McFarlane
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
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9
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Roy S, Jiang JX, Li AF, Kim D. Connexin channel and its role in diabetic retinopathy. Prog Retin Eye Res 2017; 61:35-59. [PMID: 28602949 DOI: 10.1016/j.preteyeres.2017.06.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 05/30/2017] [Accepted: 06/02/2017] [Indexed: 12/18/2022]
Abstract
Diabetic retinopathy is the leading cause of blindness in the working age population. Unfortunately, there is no cure for this devastating ocular complication. The early stage of diabetic retinopathy is characterized by the loss of various cell types in the retina, namely endothelial cells and pericytes. As the disease progresses, vascular leakage, a clinical hallmark of diabetic retinopathy, becomes evident and may eventually lead to diabetic macular edema, the most common cause of vision loss in diabetic retinopathy. Substantial evidence indicates that the disruption of connexin-mediated cellular communication plays a critical role in the pathogenesis of diabetic retinopathy. Yet, it is unclear how altered communication via connexin channel mediated cell-to-cell and cell-to-extracellular microenvironment is linked to the development of diabetic retinopathy. Recent observations suggest the possibility that connexin hemichannels may play a role in the pathogenesis of diabetic retinopathy by allowing communication between cells and the microenvironment. Interestingly, recent studies suggest that connexin channels may be involved in regulating retinal vascular permeability. These cellular events are coordinated at least in part via connexin-mediated intercellular communication and the maintenance of retinal vascular homeostasis. This review highlights the effect of high glucose and diabetic condition on connexin channels and their impact on the development of diabetic retinopathy.
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Affiliation(s)
- Sayon Roy
- Departments of Medicine and Ophthalmology, Boston University School of Medicine, Boston, MA, United States.
| | - Jean X Jiang
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX, United States
| | - An-Fei Li
- Department of Ophthalmology, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan
| | - Dongjoon Kim
- Departments of Medicine and Ophthalmology, Boston University School of Medicine, Boston, MA, United States
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Gupta A, Anderson H, Buo AM, Moorer MC, Ren M, Stains JP. Communication of cAMP by connexin43 gap junctions regulates osteoblast signaling and gene expression. Cell Signal 2016; 28:1048-57. [PMID: 27156839 DOI: 10.1016/j.cellsig.2016.04.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 04/15/2016] [Accepted: 04/28/2016] [Indexed: 11/30/2022]
Abstract
Connexin43 (Cx43) containing gap junctions play an important role in bone homeostasis, yet little is known about the second messengers communicated by Cx43 among bone cells. Here, we used MC3T3-E1 pre-osteoblasts and UMR106 rat osteosarcoma cells to test the hypothesis that cAMP is a second messenger communicated by bone cells through Cx43 containing gap junctions in a manner that is sufficient to impact osteoblast function. Overexpression of Cx43 markedly enhanced the activity of a cAMP-response element driven transcriptional luciferase reporter (CRE-luc) and increased phospho-CREB and phospho-ERK1/2 levels following expression of a constitutively active Gsα or by treatment with prostaglandin E2 (PGE2), 3-Isobutyl-1-methyl xanthine (IBMX) or forskolin. The Cx43-dependent potentiation of signaling in PGE2 treated cells was not accompanied by a further increase in cAMP levels, suggesting that the cAMP was shared between cells rather than Cx43 enhancing cAMP production. To support this, we developed a novel assay in which one set of cells expressing constitutively active Gsα (donor cells) were co-cultured with a second set of cells expressing a CRE-luc reporter (acceptor cells). Using this assay, activation of a CRE-luc reporter in the acceptor cells was both Cx43- and cell contact-dependent, indicating communication of cAMP among cells. Finally, we showed that Cx43 increased the cAMP-dependent mRNA expression of receptor activator of nuclear factor kappa B ligand (RANKL) and enhanced the repression of the sclerostin mRNA, implying a potential mechanism for the modulation of tissue remodeling. In total, these data demonstrate that Cx43 can communicate cAMP between cells and, more importantly, that the communicated cAMP is sufficient to impact signal transduction cascades and the expression of key bone effector molecules between interconnected cells.
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Affiliation(s)
- Aditi Gupta
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Hidayah Anderson
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Atum M Buo
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Megan C Moorer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Margaret Ren
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Joseph P Stains
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, USA.
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Choudhary P, Gutteridge A, Impey E, Storer RI, Owen RM, Whiting PJ, Bictash M, Benn CL. Targeting the cAMP and Transforming Growth Factor-β Pathway Increases Proliferation to Promote Re-Epithelialization of Human Stem Cell-Derived Retinal Pigment Epithelium. Stem Cells Transl Med 2016; 5:925-37. [PMID: 27112176 DOI: 10.5966/sctm.2015-0247] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Accepted: 02/01/2016] [Indexed: 12/13/2022] Open
Abstract
UNLABELLED Retinal pigment epithelium (RPE) cell integrity is critical to the maintenance of retinal function. Many retinopathies such as age-related macular degeneration (AMD) are caused by the degeneration or malfunction of the RPE cell layer. Replacement of diseased RPE with healthy, stem cell-derived RPE is a potential therapeutic strategy for treating AMD. Human embryonic stem cells (hESCs) differentiated into RPE progeny have the potential to provide an unlimited supply of cells for transplantation, but challenges around scalability and efficiency of the differentiation process still remain. Using hESC-derived RPE as a cellular model, we sought to understand mechanisms that could be modulated to increase RPE yield after differentiation. We show that RPE epithelialization is a density-dependent process, and cells seeded at low density fail to epithelialize. We demonstrate that activation of the cAMP pathway increases proliferation of dissociated RPE in culture, in part through inhibition of transforming growth factor-β (TGF-β) signaling. This results in enhanced uptake of epithelial identity, even in cultures seeded at low density. In line with these findings, targeted manipulation of the TGF-β pathway with small molecules produces an increase in efficiency of RPE re-epithelialization. Taken together, these data highlight mechanisms that promote epithelial fate acquisition in stem cell-derived RPE. Modulation of these pathways has the potential to favorably impact scalability and clinical translation of hESC-derived RPE as a cell therapy. SIGNIFICANCE Stem cell-derived retinal pigment epithelium (RPE) is currently being evaluated as a cell-replacement therapy for macular degeneration. This work shows that the process of generating RPE in vitro is regulated by the cAMP and transforming growth factor-β signaling pathway. Modulation of these pathways by small molecules, as identified by phenotypic screening, leads to an increased efficiency of generating RPE cells with a higher yield. This can have a potential impact on manufacturing transplantation-ready cells at large scale and is advantageous for clinical studies using this approach in the future.
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Affiliation(s)
- Parul Choudhary
- Pfizer Neuroscience and Pain Research Unit, Pfizer Ltd., Great Abington, Cambridge, United Kingdom
| | - Alex Gutteridge
- Pfizer Neuroscience and Pain Research Unit, Pfizer Ltd., Great Abington, Cambridge, United Kingdom
| | - Emma Impey
- Pfizer Neuroscience and Pain Research Unit, Pfizer Ltd., Great Abington, Cambridge, United Kingdom
| | - R Ian Storer
- Pfizer Worldwide Medicinal Chemistry, Pfizer Ltd., Great Abington, Cambridge, United Kingdom
| | - Robert M Owen
- Pfizer Worldwide Medicinal Chemistry, Pfizer Ltd., Great Abington, Cambridge, United Kingdom
| | - Paul J Whiting
- Pfizer Neuroscience and Pain Research Unit, Pfizer Ltd., Great Abington, Cambridge, United Kingdom
| | - Magda Bictash
- Pfizer Neuroscience and Pain Research Unit, Pfizer Ltd., Great Abington, Cambridge, United Kingdom
| | - Caroline L Benn
- Pfizer Neuroscience and Pain Research Unit, Pfizer Ltd., Great Abington, Cambridge, United Kingdom
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12
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Vitale ML, Barry A. Biphasic Effect of Basic Fibroblast Growth Factor on Anterior Pituitary Folliculostellate TtT/GF Cell Coupling, and Connexin 43 Expression and Phosphorylation. J Neuroendocrinol 2015; 27:787-801. [PMID: 26265106 DOI: 10.1111/jne.12308] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 07/08/2015] [Accepted: 08/07/2015] [Indexed: 01/01/2023]
Abstract
Basic fibroblast growth factor (bFGF) is a mitogenic and differentiating cytokine. In the anterior pituitary, folliculostellate (FS) cells constitute the major source of bFGF. bFGF affects endocrine cell proliferation and secretion in the anterior pituitary. In addition, bFGF increases its own expression by acting directly on FS cells. FS cell Cx43-mediated gap junction intercellular communication allows the establishment of an intrapituitary network for the transmission of information. In the present study, we assessed how bFGF regulates FS cell coupling. Time course studies were carried out on the FS cell line TtT/GF. Short-term bFGF treatment induced a transient cell uncoupling and the phosphorylation in Ser368 of membrane-bound Cx43 without modifying Cx43 levels. We demonstrated the involvement of the protein kinase C (PKC) isoform α in the phosphorylation of Cx43 in S368. Moreover, we showed that bFGF induced PKCα activation by stimulating its expression, phosphorylation and association with the plasma membrane. The long-term incubation with bFGF increased TtT/GF cell coupling, total Cx43 levels and Cx43 accumulation at the cell membrane of cytoplasmic projections. The Cx43 level increase was a result of the stimulation of Cx43 gene transcription as mediated by the extracellular-regulated kinase 1/2 signalling pathway. Taken together, the data show that bFGF modulates TtT/GF cell coupling by activating different pathways that lead to opposite effects on Cx43 phosphorylation and expression depending on the duration of the exposure of the cells to bFGF. A short-term bFGF exposure reduces cell-to-cell communication as a mean of desynchronising FS cells. By contrast, long-term exposure to bFGF enhances cell-to-cell communication and facilitates coordination among FS cells.
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Affiliation(s)
- M L Vitale
- Département de Pathologie et Biologie Cellulaire, Faculté de Médecine, Université de Montréal, Montreal, Québec, Canada
| | - A Barry
- Département de Pathologie et Biologie Cellulaire, Faculté de Médecine, Université de Montréal, Montreal, Québec, Canada
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13
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Oral O, Cıkım T, Zuvin M, Unal O, Yagci-Acar H, Gozuacik D, Koşar A. Effect of Varying Magnetic Fields on Targeted Gene Delivery of Nucleic Acid-Based Molecules. Ann Biomed Eng 2015; 43:2816-26. [DOI: 10.1007/s10439-015-1331-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 05/02/2015] [Indexed: 12/14/2022]
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14
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Bertolotti E, Neri A, Camparini M, Macaluso C, Marigo V. Stem cells as source for retinal pigment epithelium transplantation. Prog Retin Eye Res 2014; 42:130-44. [PMID: 24933042 DOI: 10.1016/j.preteyeres.2014.06.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 05/30/2014] [Accepted: 06/05/2014] [Indexed: 12/27/2022]
Abstract
Inherited maculopathies, age related macular degeneration and some forms of retinitis pigmentosa are associated with impaired function or loss of the retinal pigment epithelium (RPE). Among potential treatments, transplantation approaches are particularly promising. The arrangement of RPE cells in a well-defined tissue layer makes the RPE amenable to cell or tissue sheet transplantation. Different cell sources have been suggested for RPE transplantation but the development of a clinical protocol faces several obstacles. The source should provide a sufficient number of cells to at least recover the macula area. Secondly, cells should be plastic enough to be able to integrate in the host tissue. Tissue sheets should be considered as well, but the substrate on which RPE cells are cultured needs to be carefully evaluated. Immunogenicity can also be an obstacle for effective transplantation as well as tumorigenicity of not fully differentiated cells. Finally, ethical concerns may represent drawbacks when embryo-derived cells are proposed for RPE transplantation. Here we discuss different cell sources that became available in recent years and their different properties. We also present data on a new source of human RPE. We provide a protocol for RPE differentiation of retinal stem cells derived from adult ciliary bodies of post-mortem donors. We show molecular characterization of the in vitro differentiated RPE tissue and demonstrate its functionality based on a phagocytosis assay. This new source may provide tissue for allogenic transplantation based on best matches through histocompatibility testing.
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Affiliation(s)
- Evelina Bertolotti
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Alberto Neri
- Ophthalmology, S.Bi.Bi.T. Department, University of Parma, Parma, Italy
| | - Monica Camparini
- Ophthalmology, S.Bi.Bi.T. Department, University of Parma, Parma, Italy
| | - Claudio Macaluso
- Ophthalmology, S.Bi.Bi.T. Department, University of Parma, Parma, Italy
| | - Valeria Marigo
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy.
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15
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Ning N, Wen Y, Li Y, Li J. Meclofenamic acid blocks the gap junction communication between the retinal pigment epithelial cells. Hum Exp Toxicol 2013; 32:1164-9. [PMID: 23584353 DOI: 10.1177/0960327112472997] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
AIM Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to manage the pain and inflammation. NSAIDs can cause serious side effects, including vision problems. However, the underlying mechanisms are still unclear. Therefore, we aimed to investigate the effect of meclofenamic acid (MFA) on retinal pigment epithelium (RPE). MATERIALS AND METHODS In our study, we applied image analysis and whole-cell patch clamp recording to directly measure the effect of MFA on the gap junctional coupling between RPE cells. RESULTS Analysis of Lucifer yellow (LY) transfer revealed that the gap junction communication existed between RPE cells. Functional experiments using the whole-cell configuration of the patch clamp technique showed that a gap junction conductance also existed between this kind of cells. Importantly, MFA largely inhibited the gap junction conductance and induced the uncoupling of RPE cells. Other NSAIDs, like aspirin and flufenamic acid (FFA), had the same effect. CONCLUSION The gap junction functionally existed in RPE cells, which can be blocked by MFA. These findings may explain, at least partially, the vision problems with certain clinically used NSAIDs.
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Affiliation(s)
- N Ning
- 1Department of Physiology, Shandong University School of Medicine, Jinan, China
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16
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Abu Khamidakh A, Juuti-Uusitalo K, Larsson K, Skottman H, Hyttinen J. Intercellular Ca2+ wave propagation in human retinal pigment epithelium cells induced by mechanical stimulation. Exp Eye Res 2013; 108:129-39. [DOI: 10.1016/j.exer.2013.01.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 01/10/2013] [Accepted: 01/14/2013] [Indexed: 01/19/2023]
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17
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Effects of cultured human adipose-derived stem cells transplantation on rabbit cornea regeneration after alkaline chemical burn. Kaohsiung J Med Sci 2013; 29:14-8. [DOI: 10.1016/j.kjms.2012.08.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Accepted: 01/18/2012] [Indexed: 11/19/2022] Open
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18
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SanGiovanni JP, Neuringer M. The putative role of lutein and zeaxanthin as protective agents against age-related macular degeneration: promise of molecular genetics for guiding mechanistic and translational research in the field. Am J Clin Nutr 2012; 96:1223S-33S. [PMID: 23053548 PMCID: PMC3471204 DOI: 10.3945/ajcn.112.038240] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Age-related macular degeneration (AMD) is the primary cause of vision loss in elderly people of western European ancestry. Genetic, dietary, and environmental factors affect tissue concentrations of macular xanthophylls (MXs) within retinal cell types manifesting AMD pathology. In this article we review the history and state of science on the putative role of the MXs (lutein, zeaxanthin, and meso-zeaxanthin) in AMD and report findings on AMD-associated genes encoding enzymes, transporters, ligands, and receptors affecting or affected by MXs. We then use this context to discuss emerging research opportunities that offer promise for meaningful investigation and inference in the field.
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19
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Phenotypic plasticity of retinal pigment epithelial cells from adult human eye in vitro. Bull Exp Biol Med 2012; 151:506-11. [PMID: 22448378 DOI: 10.1007/s10517-011-1368-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Phenotypic plasticity of retinal pigment epithelial cells from adult human eye was studied by immunohistochemical methods under different culturing conditions. It was found that retinal pigment epithelium in adult human eye is a heterogeneous population of cells demonstrating different behavior in vitro. Some cells retain epithelial morphology for a long time in culture, while others are rapidly transformed into fibroblast-like cells and synthesize proteins typical of proneural, neural, glial, and photoreceptor cells. However, irrespective of initial morphological features differentiation of retinal pigment cells can be modulated by varying culturing conditions.
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20
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Plank C, Zelphati O, Mykhaylyk O. Magnetically enhanced nucleic acid delivery. Ten years of magnetofection-progress and prospects. Adv Drug Deliv Rev 2011; 63:1300-31. [PMID: 21893135 PMCID: PMC7103316 DOI: 10.1016/j.addr.2011.08.002] [Citation(s) in RCA: 251] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 08/18/2011] [Accepted: 08/19/2011] [Indexed: 12/28/2022]
Abstract
Nucleic acids carry the building plans of living systems. As such, they can be exploited to make cells produce a desired protein, or to shut down the expression of endogenous genes or even to repair defective genes. Hence, nucleic acids are unique substances for research and therapy. To exploit their potential, they need to be delivered into cells which can be a challenging task in many respects. During the last decade, nanomagnetic methods for delivering and targeting nucleic acids have been developed, methods which are often referred to as magnetofection. In this review we summarize the progress and achievements in this field of research. We discuss magnetic formulations of vectors for nucleic acid delivery and their characterization, mechanisms of magnetofection, and the application of magnetofection in viral and nonviral nucleic acid delivery in cell culture and in animal models. We summarize results that have been obtained with using magnetofection in basic research and in preclinical animal models. Finally, we describe some of our recent work and end with some conclusions and perspectives.
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21
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Gallagher-Colombo S, Maminishkis A, Tate S, Grunwald GB, Philp NJ. Modulation of MCT3 expression during wound healing of the retinal pigment epithelium. Invest Ophthalmol Vis Sci 2010; 51:5343-50. [PMID: 20505202 DOI: 10.1167/iovs.09-5028] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE MCT3 is a proton-coupled monocarboxylate transporter preferentially expressed in the basolateral membrane of the retinal pigment epithelium (RPE) and has been shown to play an important role in regulating pH and lactate concentrations in the outer retina. Decreased expression of MCT3 in response to trauma or disease could contribute to pathologic changes in the retina. The present study followed the expression of MCT3 after wounding and re-epithelialization of chick RPE explant and human fetal (hf) RPE cultures. METHODS Immunofluorescence microscopy and immunoblotting were performed to determine changes in MCT expression after scratch wounding and re-epithelialization of chick RPE/choroid explant cultures and hfRPE cell monolayers. RESULTS MCT3 expression and basolateral polarity were maintained in chick RPE/choroid explant cultures and hfRPE monolayers. Wounding resulted in loss of MCT3 and the upregulation of MCT4 expression in migrating cells at the edge of the wound. On re-epithelialization, MCT3 was detected in chick and hfRPE cells when cells became hexagonally packed and pigmented. However, in hfRPE cells, MCT4 was consistently expressed throughout the epithelial monolayer. RPE cells at the edges of chick explants and hfRPE cultures with a free edge expressed MCT4 but not MCT3. CONCLUSIONS Wounding of RPE monolayers resulted in dedifferentiation of the cells at the edge of the wound, as evidenced by a loss of MCT3 and increased MCT4 expression. Collectively, these findings suggest that both cell-cell and cell-substrate interactions are essential in directing and maintaining differentiation of the RPE and expression of MCT3.
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Affiliation(s)
- Shannon Gallagher-Colombo
- Department of Pathology, Anatomy, and Cell Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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22
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Nihei OK, Fonseca PC, Rubim NM, Bonavita AG, Lyra JSPO, Neves-dos-Santos S, de Carvalho ACC, Spray DC, Savino W, Alves LA. Modulatory effects of cAMP and PKC activation on gap junctional intercellular communication among thymic epithelial cells. BMC Cell Biol 2010; 11:3. [PMID: 20078861 PMCID: PMC2823718 DOI: 10.1186/1471-2121-11-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Accepted: 01/15/2010] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND We investigated the effects of the signaling molecules, cyclic AMP (cAMP) and protein-kinase C (PKC), on gap junctional intercellular communication (GJIC) between thymic epithelial cells (TEC). RESULTS Treatment with 8-Br-cAMP, a cAMP analog; or forskolin, which stimulates cAMP production, resulted in an increase in dye transfer between adjacent TEC, inducing a three-fold enhancement in the mean fluorescence of coupled cells, ascertained by flow cytometry after calcein transfer. These treatments also increased Cx43 mRNA expression, and stimulated Cx43 protein accumulation in regions of intercellular contacts. VIP, adenosine, and epinephrine which may also signal through cyclic nucleotides were tested. The first two molecules did not mimic the effects of 8-Br-cAMP, however epinephrine was able to increase GJIC suggesting that this molecule functions as an endogenous inter-TEC GJIC modulators. Stimulation of PKC by phorbol-myristate-acetate inhibited inter-TEC GJIC. Importantly, both the enhancing and the decreasing effects, respectively induced by cAMP and PKC, were observed in both mouse and human TEC preparations. Lastly, experiments using mouse thymocyte/TEC heterocellular co-cultures suggested that the presence of thymocytes does not affect the degree of inter-TEC GJIC. CONCLUSIONS Overall, our data indicate that cAMP and PKC intracellular pathways are involved in the homeostatic control of the gap junction-mediated communication in the thymic epithelium, exerting respectively a positive and negative role upon cell coupling. This control is phylogenetically conserved in the thymus, since it was seen in both mouse and human TEC preparations. Lastly, our work provides new clues for a better understanding of how the thymic epithelial network can work as a physiological syncytium.
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Affiliation(s)
- Oscar K Nihei
- Laboratory of Cellular Communication, Oswaldo Cruz Institute, The Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Laboratory of Thymus Research, Oswaldo Cruz Institute, The Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Paula C Fonseca
- Laboratory of Cellular Communication, Oswaldo Cruz Institute, The Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Nara M Rubim
- Laboratory of Cellular Communication, Oswaldo Cruz Institute, The Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Andre G Bonavita
- Laboratory of Cellular Communication, Oswaldo Cruz Institute, The Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Jurandy SPO Lyra
- Laboratory of Thymus Research, Oswaldo Cruz Institute, The Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Department of Pathology, Federal University of Rio de Janeiro State (UNIRIO), Rio de Janeiro, Brazil
| | - Sandra Neves-dos-Santos
- Laboratory of Thymus Research, Oswaldo Cruz Institute, The Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Department of Clinical Analysis, Faculty of Pharmacy, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | | | - David C Spray
- The Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, New York, USA
| | - Wilson Savino
- Laboratory of Thymus Research, Oswaldo Cruz Institute, The Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Luiz A Alves
- Laboratory of Cellular Communication, Oswaldo Cruz Institute, The Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
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Milyushina LA, Poltavtseva RA, Marei MV, Podgornyi OV, Sukhikh GT, Aleksandrova MA. In Vitro Phenotypic Modifi cation of Pigmented Epithelium Cells from Human Eye at Early Stages of Development. Bull Exp Biol Med 2009; 148:113-9. [DOI: 10.1007/s10517-009-0657-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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24
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Sengupta N, Caballero S, Sullivan SM, Chang LJ, Afzal A, Li Calzi S, Kielczewski JL, Prabarakan S, Ellis EA, Moldovan L, Moldovan NI, Boulton ME, Grant MB, Scott EW, Harris JR. Regulation of adult hematopoietic stem cells fate for enhanced tissue-specific repair. Mol Ther 2009; 17:1594-604. [PMID: 19584817 PMCID: PMC2835259 DOI: 10.1038/mt.2009.145] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Accepted: 06/01/2009] [Indexed: 12/29/2022] Open
Abstract
The ability to control the differentiation of adult hematopoietic stem cells (HSCs) would promote development of new cell-based therapies to treat multiple degenerative diseases. Systemic injection of NaIO(3) was used to ablate the retinal pigment epithelial (RPE) layer in C57Bl6 mice and initiate neural retinal degeneration. HSCs infected ex vivo with lentiviral vector expressing the RPE-specific gene RPE65 restored a functional RPE layer, with typical RPE phenotype including coexpression of another RPE-specific marker, CRALBP, and photoreceptor outer segment phagocytosis. Retinal degeneration was prevented and visual function, as measured by electroretinography (ERG), was restored to levels similar to that found in normal animals. None of the controls (no HSCs, HSCs alone and HSCs infected with lentiviral vector expressing LacZ) showed these effects. In vitro gene array studies demonstrated that infection of HSC with RPE65 increased adenylate cyclase mRNA. In vitro exposure of HSCs to a pharmacological agonist of adenylate cyclase also led to in vitro differentiation of HSCs to RPE-like cells expressing pigment granules and the RPE-specific marker, CRALBP. Our data confirm that expression of the cell-specific gene RPE65 promoted fate determination of HSCs toward RPE for targeted tissue repair, and did so in part by activation of adenylate cyclase signaling pathways. Expression by HSCs of single genes unique to a differentiated cell may represent a novel experimental paradigm to influence HSC plasticity, force selective differentiation, and ultimately lead to identification of pharmacological alternatives to viral gene delivery.
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Affiliation(s)
- Nilanjana Sengupta
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, Florida 32610-0267, USA
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25
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Cook JE, Becker DL. Gap-Junction Proteins in Retinal Development: New Roles for the “Nexus”. Physiology (Bethesda) 2009; 24:219-30. [DOI: 10.1152/physiol.00007.2009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Gap-junction channels, the cytoplasmic proteins that associate with them, and the transcriptional networks that regulate them are increasingly being viewed as critical communications hubs for cell signaling in health and disease. As a result, the term “nexus,” which was the original structural name for these focal intercellular links, is coming back into use with new proteomic and transcriptomic meanings. The retina is better understood than any other part of the vertebrate central nervous system in respect of its developmental patterning, its diverse neuronal types and circuits, and the emergence of its definitive structure-function correlations. Thus, studies of the junctional and nonjunctional nexus roles of gap-junction proteins in coordinating retinal development should throw useful light on cell signaling in other developing nervous tissues.
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Affiliation(s)
- Jeremy E. Cook
- Department of Cell and Developmental Biology, University College London, Gower Street, London, United Kingdom
| | - David L. Becker
- Department of Cell and Developmental Biology, University College London, Gower Street, London, United Kingdom
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26
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Differential immunodetection of
l
‐DOPA decarboxylase and tyrosine hydroxylase in the vertebrate retina. Int J Dev Neurosci 2009; 27:469-76. [DOI: 10.1016/j.ijdevneu.2009.05.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 04/23/2009] [Accepted: 05/06/2009] [Indexed: 11/19/2022] Open
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27
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Schubert SW, Abendroth A, Kilian K, Vogler T, Mayr B, Knerr I, Hashemolhosseini S. bZIP-Type transcription factors CREB and OASIS bind and stimulate the promoter of the mammalian transcription factor GCMa/Gcm1 in trophoblast cells. Nucleic Acids Res 2008; 36:3834-46. [PMID: 18495750 PMCID: PMC2441803 DOI: 10.1093/nar/gkn306] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
One of the master regulators of placental cell fusion in mammals leading to multi-nucleated syncytiotrophoblasts is the transcription factor GCMa. Recently, we proved that the cAMP-driven protein kinase A signaling pathway is fundamental for up-regulation of GCMa transcript levels and protein stability. Here, we show that Transducer of Regulated CREB activity (TORC1), the human co-activator of cAMP response element-binding protein (CREB), but not a dominant-negative CREB mutant, significantly up-regulates the GCMa promoter. We identified potential cAMP response element (CRE)-binding sites within the GCMa promoter upstream of the transcriptional start site. Only the CRE site at -1337 interacted strongly with CREB in promoter mapping experiments. The characterization of GCMa promoter mutants and additional bZIP-type family members demonstrated that also old astrocyte specifically-induced substance (OASIS) is able to stimulate GCMa transcription. Knockdown of endogenous CREB or OASIS in BeWo cells decreased endogenous GCMa mRNA level and activity. Overexpression of TORC1 or OASIS in choriocarcinoma cells led to placental cell fusion, accompanied by placental expression of gap junction forming protein connexin-43. Further, we show that CREB expression is replaced by OASIS expression around E12.5 suggesting that a sequential order of bZIP-type family members ensures a high rate of GCMa transcription throughout placentation.
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Affiliation(s)
- Steffen Wolfgang Schubert
- Institut für Biochemie, Emil-Fischer-Zentrum, Kinder- und Jugendklinik and Nikolaus-Fiebiger-Zentrum, Universität Erlangen-Nürnberg, Fahrstrasse 17, D-91054 Erlangen, Germany
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