51
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Santos-Ferreira T, Llonch S, Borsch O, Postel K, Haas J, Ader M. Retinal transplantation of photoreceptors results in donor-host cytoplasmic exchange. Nat Commun 2016; 7:13028. [PMID: 27701381 PMCID: PMC5059459 DOI: 10.1038/ncomms13028] [Citation(s) in RCA: 188] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 08/23/2016] [Indexed: 12/12/2022] Open
Abstract
Pre-clinical studies provided evidence for successful photoreceptor cell replacement therapy. Migration and integration of donor photoreceptors into the retina has been proposed as the underlying mechanism for restored visual function. Here we reveal that donor photoreceptors do not structurally integrate into the retinal tissue but instead reside between the photoreceptor layer and the retinal pigment epithelium, the so-called sub-retinal space, and exchange intracellular material with host photoreceptors. By combining single-cell analysis, Cre/lox technology and independent labelling of the cytoplasm and nucleus, we reliably track allogeneic transplants demonstrating cellular content transfer between graft and host photoreceptors without nuclear translocation. Our results contradict the common view that transplanted photoreceptors migrate and integrate into the photoreceptor layer of recipients and therefore imply a re-interpretation of previous photoreceptor transplantation studies. Furthermore, the observed interaction of donor with host photoreceptors may represent an unexpected mechanism for the treatment of blinding diseases in future cell therapy approaches.
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Affiliation(s)
- Tiago Santos-Ferreira
- CRTD/Center for Regenerative Therapies Dresden, Technische Universität Dresden, Fetscherstrasse 105, 01307 Dresden, Germany
| | - Sílvia Llonch
- CRTD/Center for Regenerative Therapies Dresden, Technische Universität Dresden, Fetscherstrasse 105, 01307 Dresden, Germany
| | - Oliver Borsch
- CRTD/Center for Regenerative Therapies Dresden, Technische Universität Dresden, Fetscherstrasse 105, 01307 Dresden, Germany
| | - Kai Postel
- CRTD/Center for Regenerative Therapies Dresden, Technische Universität Dresden, Fetscherstrasse 105, 01307 Dresden, Germany
| | - Jochen Haas
- CRTD/Center for Regenerative Therapies Dresden, Technische Universität Dresden, Fetscherstrasse 105, 01307 Dresden, Germany
| | - Marius Ader
- CRTD/Center for Regenerative Therapies Dresden, Technische Universität Dresden, Fetscherstrasse 105, 01307 Dresden, Germany
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52
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Chen Y, Pu J, Zhang B. Progress and Challenges of Cell Replacement Therapy for Neurodegenerative Diseases Based on Direct Neural Reprogramming. Hum Gene Ther 2016; 27:962-970. [PMID: 27589383 DOI: 10.1089/hum.2016.078] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Neurodegenerative diseases are characterized by protein aggregation and progressive degeneration of neurons, causing severe functional deficiency in cognition, behavior, and movement. Until now, there has been no effective treatment available in the clinic. Considering the selective loss of specific neurons in the human brain in the pathogenesis of these diseases, generating functional neurons in vitro or in vivo to replace the lost neurons represents a novel strategy to treat neurodegenerative diseases. Human embryonic stem cells and induced pluripotent stem cells have good potential for cell replacement therapy. However, limitations, such as the possibility of tumor formation, have hindered its applications. Recently, a novel approach, direct neural reprogramming, in which somatic cells are reprogrammed to functional neurons without a stem-cell state, has emerged an alternative for cell replacement. Specific human somatic cells can be reprogrammed to functional subtype neurons via the introduction of transcription factors, microRNAs, or small molecules in vitro and in vivo, thereby reducing the risk of carcinogenesis. Studies demonstrated symptomatic relief when induced neurons were transplanted into animal models. Although the direct neural reprogramming holds great promise for cell replacement therapy, there remain a number of challenges for its clinical application, including low efficiency, unclear mechanisms, and safety concerns. This review highlights the progress and challenges of this technique, and discusses perspectives for its applications in cell replacement.
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Affiliation(s)
- Ying Chen
- Department of Neurology, 2nd Affiliated Hospital, School of Medicine, Zhejiang University , Zhejiang, People's Republic of China
| | - Jiali Pu
- Department of Neurology, 2nd Affiliated Hospital, School of Medicine, Zhejiang University , Zhejiang, People's Republic of China
| | - Baorong Zhang
- Department of Neurology, 2nd Affiliated Hospital, School of Medicine, Zhejiang University , Zhejiang, People's Republic of China
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Izquierdo-Serra M, Bautista-Barrufet A, Trapero A, Garrido-Charles A, Díaz-Tahoces A, Camarero N, Pittolo S, Valbuena S, Pérez-Jiménez A, Gay M, García-Moll A, Rodríguez-Escrich C, Lerma J, de la Villa P, Fernández E, Pericàs MÀ, Llebaria A, Gorostiza P. Optical control of endogenous receptors and cellular excitability using targeted covalent photoswitches. Nat Commun 2016; 7:12221. [PMID: 27436051 PMCID: PMC4961765 DOI: 10.1038/ncomms12221] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 06/10/2016] [Indexed: 12/15/2022] Open
Abstract
Light-regulated drugs allow remotely photoswitching biological activity and enable plausible therapies based on small molecules. However, only freely diffusible photochromic ligands have been shown to work directly in endogenous receptors and methods for covalent attachment depend on genetic manipulation. Here we introduce a chemical strategy to covalently conjugate and photoswitch the activity of endogenous proteins and demonstrate its application to the kainate receptor channel GluK1. The approach is based on photoswitchable ligands containing a short-lived, highly reactive anchoring group that is targeted at the protein of interest by ligand affinity. These targeted covalent photoswitches (TCPs) constitute a new class of light-regulated drugs and act as prosthetic molecules that photocontrol the activity of GluK1-expressing neurons, and restore photoresponses in degenerated retina. The modularity of TCPs enables the application to different ligands and opens the way to new therapeutic opportunities. Biological activity can be photoswitched by light-regulated drugs, but so far only diffusible ligands have been shown to work on endogenous receptors. Here the authors develop targeted covalent photoswitches that couple to a protein target by ligand affinity, and demonstrate photocontrol of GluK1-expressing neurons.
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Affiliation(s)
| | - Antoni Bautista-Barrufet
- Institut de Bioenginyeria de Catalunya (IBEC), Barcelona 08028, Spain.,Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Tarragona 43007, Spain
| | - Ana Trapero
- Institut de Bioenginyeria de Catalunya (IBEC), Barcelona 08028, Spain.,Institut de Química Avançada de Catalunya (IQAC-CSIC), Barcelona 08034, Spain
| | | | - Ariadna Díaz-Tahoces
- Instituto de Bioingeniería, Universidad Miguel Hernández (UMH), Elche 03202, Spain
| | - Nuria Camarero
- Institut de Bioenginyeria de Catalunya (IBEC), Barcelona 08028, Spain
| | - Silvia Pittolo
- Institut de Bioenginyeria de Catalunya (IBEC), Barcelona 08028, Spain
| | - Sergio Valbuena
- Instituto de Neurociencias (CSIC-UMH), San Juan de Alicante 03550, Spain
| | | | - Marina Gay
- Institut de Recerca en Biomedicina (IRBB), Barcelona 08028, Spain
| | | | - Carles Rodríguez-Escrich
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Tarragona 43007, Spain
| | - Juan Lerma
- Instituto de Neurociencias (CSIC-UMH), San Juan de Alicante 03550, Spain
| | - Pedro de la Villa
- Universidad de Alcalá de Henares (UAH), Alcalá de Henares 28871, Spain
| | - Eduardo Fernández
- Instituto de Bioingeniería, Universidad Miguel Hernández (UMH), Elche 03202, Spain.,Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Zaragoza 50018, Spain
| | - Miquel À Pericàs
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Tarragona 43007, Spain.,Departament de Química Inorgànica i Orgànica, Universitat de Barcelona (UB), Barcelona 08007, Spain
| | - Amadeu Llebaria
- Institut de Química Avançada de Catalunya (IQAC-CSIC), Barcelona 08034, Spain
| | - Pau Gorostiza
- Institut de Bioenginyeria de Catalunya (IBEC), Barcelona 08028, Spain.,Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Zaragoza 50018, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona 08010, Spain
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54
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Sanges D, Simonte G, Di Vicino U, Romo N, Pinilla I, Nicolás M, Cosma MP. Reprogramming Müller glia via in vivo cell fusion regenerates murine photoreceptors. J Clin Invest 2016; 126:3104-16. [PMID: 27427986 DOI: 10.1172/jci85193] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 05/24/2016] [Indexed: 12/17/2022] Open
Abstract
Vision impairments and blindness caused by retinitis pigmentosa result from severe neurodegeneration that leads to a loss of photoreceptors, the specialized light-sensitive neurons that enable vision. Although the mammalian nervous system is unable to replace neurons lost due to degeneration, therapeutic approaches to reprogram resident glial cells to replace retinal neurons have been proposed. Here, we demonstrate that retinal Müller glia can be reprogrammed in vivo into retinal precursors that then differentiate into photoreceptors. We transplanted hematopoietic stem and progenitor cells (HSPCs) into retinas affected by photoreceptor degeneration and observed spontaneous cell fusion events between Müller glia and the transplanted cells. Activation of Wnt signaling in the transplanted HSPCs enhanced survival and proliferation of Müller-HSPC hybrids as well as their reprogramming into intermediate photoreceptor precursors. This suggests that Wnt signaling drives the reprogrammed cells toward a photoreceptor progenitor fate. Finally, Müller-HSPC hybrids differentiated into photoreceptors. Transplantation of HSPCs with activated Wnt functionally rescued the retinal degeneration phenotype in rd10 mice, a model for inherited retinitis pigmentosa. Together, these results suggest that photoreceptors can be generated by reprogramming Müller glia and that this approach may have potential as a strategy for reversing retinal degeneration.
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55
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Cell-cell fusion in the nervous system: Alternative mechanisms of development, injury, and repair. Semin Cell Dev Biol 2016; 60:146-154. [PMID: 27375226 DOI: 10.1016/j.semcdb.2016.06.019] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/14/2016] [Accepted: 06/28/2016] [Indexed: 12/11/2022]
Abstract
Over a century ago, the seminal work of Ramón y Cajal revealed that the nervous system is made of individual units, the neurons, which are related to each other by contiguity rather than continuity. This view overturned the idea that the nervous system was a reticulum of fibers, a rete diffusa nervosa, as proposed and defined by Camillo Golgi. Although the neuron theory has been widely confirmed in every model system studied and constitutes the basis of modern neuroscience, evidence accumulated over the years suggests that neurons, similar to other types of cells, have the potential to fuse their membranes and undergo cell-cell fusion under certain conditions. This concept adds a substantial layer to our view of the nervous system and how it functions. Here, we bring together past and more recent discoveries on multiple aspects of neuronal fusion, discussing how this cellular event is generated, and what consequences it has for our understanding of nervous system development, disease, injury, and repair.
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56
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Stem Cell Therapy for Treatment of Ocular Disorders. Stem Cells Int 2016; 2016:8304879. [PMID: 27293447 PMCID: PMC4884591 DOI: 10.1155/2016/8304879] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 04/10/2016] [Indexed: 12/30/2022] Open
Abstract
Sustenance of visual function is the ultimate focus of ophthalmologists. Failure of complete recovery of visual function and complications that follow conventional treatments have shifted search to a new form of therapy using stem cells. Stem cell progenitors play a major role in replenishing degenerated cells despite being present in low quantity and quiescence in our body. Unlike other tissues and cells, regeneration of new optic cells responsible for visual function is rarely observed. Understanding the transcription factors and genes responsible for optic cells development will assist scientists in formulating a strategy to activate and direct stem cells renewal and differentiation. We review the processes of human eye development and address the strategies that have been exploited in an effort to regain visual function in the preclinical and clinical state. The update of clinical findings of patients receiving stem cell treatment is also presented.
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57
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Altarche-Xifro W, di Vicino U, Muñoz-Martin MI, Bortolozzi A, Bové J, Vila M, Cosma MP. Functional Rescue of Dopaminergic Neuron Loss in Parkinson's Disease Mice After Transplantation of Hematopoietic Stem and Progenitor Cells. EBioMedicine 2016; 8:83-95. [PMID: 27428421 PMCID: PMC4919540 DOI: 10.1016/j.ebiom.2016.04.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 04/14/2016] [Indexed: 01/24/2023] Open
Abstract
Parkinson's disease is a common neurodegenerative disorder, which is due to the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and for which no definitive cure is currently available. Cellular functions in mouse and human tissues can be restored after fusion of bone marrow (BM)-derived cells with a variety of somatic cells. Here, after transplantation of hematopoietic stem and progenitor cells (HSPCs) in the SNpc of two different mouse models of Parkinson's disease, we significantly ameliorated the dopaminergic neuron loss and function. We show fusion of transplanted HSPCs with neurons and with glial cells in the ventral midbrain of Parkinson's disease mice. Interestingly, the hybrids can undergo reprogramming in vivo and survived up to 4 weeks after transplantation, while acquiring features of mature astroglia. These newly generated astroglia produced Wnt1 and were essential for functional rescue of the dopaminergic neurons. Our data suggest that glial-derived hybrids produced upon fusion of transplanted HSPCs in the SNpc can rescue the Parkinson's disease phenotype via a niche-mediated effect, and can be exploited as an efficient cell-therapy approach. Transplantation of HSPCs into the substantia nigra of PD mice ameliorates dopaminergic neuron loss and function. Hybrids generated after fusion of transplanted HSPCs undergo reprogramming in vivo and acquire features of mature astroglia. Newly generated astroglia produced Wnt1 and can functionally rescue the dopaminergic neuron loss.
A definitive therapy for Parkinson's disease is not available. Here, we transplanted hematopoietic stem and progenitor cells into the substantia nigra of brains of two different mouse models of Parkinson's disease. These transplanted cells fused with neurons and glial cells of the recipient mice. Four weeks after transplantation, the hybrids acquired features of mature astroglia, secreted Wnt1, and functionally ameliorated dopaminergic neuron loss. Current cell therapy approaches are being pursued in the striatum with the aim to increase dopamine levels. Here we show that the loss of dopaminergic neurons can be protected against by direct actions in the substantia nigra.
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Affiliation(s)
- Wassim Altarche-Xifro
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain; Universitat Pompeu Fabra (UPF), Dr Aiguader 88, 08003 Barcelona, Spain
| | - Umberto di Vicino
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain; Universitat Pompeu Fabra (UPF), Dr Aiguader 88, 08003 Barcelona, Spain
| | - Maria Isabel Muñoz-Martin
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain; Universitat Pompeu Fabra (UPF), Dr Aiguader 88, 08003 Barcelona, Spain
| | - Analía Bortolozzi
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) and Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, Spain; Department of Neurochemistry and Neuropharmacology, IIBB-CSIC (Consejo Superior de Investigaciones Científicas), Barcelona, Spain
| | - Jordi Bové
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute and Centre for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Barcelona, Spain
| | - Miquel Vila
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute and Centre for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Barcelona, Spain; Department of Biochemistry and Molecular Biology, Autonomous University of Barcelona (UAB), Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain
| | - Maria Pia Cosma
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain; Universitat Pompeu Fabra (UPF), Dr Aiguader 88, 08003 Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain.
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58
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Venugopalan P, Wang Y, Nguyen T, Huang A, Muller KJ, Goldberg JL. Transplanted neurons integrate into adult retinas and respond to light. Nat Commun 2016; 7:10472. [PMID: 26843334 PMCID: PMC4742891 DOI: 10.1038/ncomms10472] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 12/16/2015] [Indexed: 12/12/2022] Open
Abstract
Retinal ganglion cells (RGCs) degenerate in diseases like glaucoma and are not replaced in adult mammals. Here we investigate whether transplanted RGCs can integrate into the mature retina. We have transplanted GFP-labelled RGCs into uninjured rat retinas in vivo by intravitreal injection. Transplanted RGCs acquire the general morphology of endogenous RGCs, with axons orienting towards the optic nerve head of the host retina and dendrites growing into the inner plexiform layer. Preliminary data show in some cases GFP(+) axons extending within the host optic nerves and optic tract, reaching usual synaptic targets in the brain, including the lateral geniculate nucleus and superior colliculus. Electrophysiological recordings from transplanted RGCs demonstrate the cells' electrical excitability and light responses similar to host ON, ON-OFF and OFF RGCs, although less rapid and with greater adaptation. These data present a promising approach to develop cell replacement strategies in diseased retinas with degenerating RGCs.
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Affiliation(s)
- Praseeda Venugopalan
- Neuroscience Program, University of Miami, Miami, Florida 33136, USA.,Shiley Eye Center, University of California, San Diego, California 92093, USA
| | - Yan Wang
- Shiley Eye Center, University of California, San Diego, California 92093, USA
| | - Tu Nguyen
- Shiley Eye Center, University of California, San Diego, California 92093, USA
| | - Abigail Huang
- Shiley Eye Center, University of California, San Diego, California 92093, USA
| | - Kenneth J Muller
- Neuroscience Program, University of Miami, Miami, Florida 33136, USA.,Department of Physiology and Biophysics, University of Miami Miller School of Medicine, Miami, Florida 33136, USA
| | - Jeffrey L Goldberg
- Neuroscience Program, University of Miami, Miami, Florida 33136, USA.,Shiley Eye Center, University of California, San Diego, California 92093, USA.,Byers Eye Institute, Department of Ophthalmology, Stanford University, Stanford, California 94303, USA
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59
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Xie H, Jing Y, Xia J, Wang X, You C, Yan J. Aquaporin 3 protects against lumbar intervertebral disc degeneration via the Wnt/β-catenin pathway. Int J Mol Med 2016; 37:859-64. [PMID: 26820815 DOI: 10.3892/ijmm.2016.2470] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 01/05/2016] [Indexed: 11/06/2022] Open
Abstract
Previous studies have demonstrated that the expression of aquaporin 3 (AQP3), a water channel which promotes glycerol permeability and water transport across cell membranes, is reduced in degenerative lumbar intervertebral disc (IVD) tissues. However, the role of AQP3 in the pathogenesis of IVD degeneration has not recieved much scholarly attention. The objective of the present study was to investigate the effect of AQP3 on cell proliferation and extracellular matrix (ECM) degradation in human nucleus pulposus cells (hNPCs) using gain-of-function and loss-of-function experiments, and to determine whether Wnt/β-catenin signaling is involved in the effect of AQP3 on IVD degeneration. hNPCs were transfected with the AQP3-pcDNA3.1 plasmid or AQP3 siRNA to overexpress or suppress AQP3. An MTT assay was performed to determine cell proliferation, and we found that AQP3 promoted hNPC proliferation. The expression of aggrecan, a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)4 and ADAMTS5 was detected using western blot analysis, to examine the effect of AQP3 on ECM degradation in hNPCs. The results revealed that AQP3 inhibited ECM degradation in hNPCs. In addition, we found that Wnt/β-catenin signaling was suppressed by AQP3. However, the effect of AQP3 on hNPC proliferation and ECM degradation was reversed by treatment with lithium chloride, a known activator of Wnt/β‑catenin signaling. In conclusion, using in vitro and in vivo tests, we have reported for the first time, to the best of our knowledge, that AQP3 exerts protective effects against IVD degeneration, and these are effected, at least partially, through the inhibition of Wnt/β-catenin signaling.
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Affiliation(s)
- Huanxin Xie
- Department of Orthopedic Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Yongbin Jing
- Department of Orthopedic Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Jingjun Xia
- Department of Orthopedic Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Xintao Wang
- Department of Orthopedic Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Changcheng You
- Department of Orthopedic Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Jinglong Yan
- Department of Orthopedic Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
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60
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Wang Q, Stern JH, Temple S. Regenerative Medicine: Solution in Sight. RETINAL DEGENERATIVE DISEASES 2016; 854:543-8. [DOI: 10.1007/978-3-319-17121-0_72] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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61
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Nash KM, Shah ZA. Current Perspectives on the Beneficial Role of Ginkgo biloba in Neurological and Cerebrovascular Disorders. INTEGRATIVE MEDICINE INSIGHTS 2015; 10:1-9. [PMID: 26604665 PMCID: PMC4640423 DOI: 10.4137/imi.s25054] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 10/01/2015] [Accepted: 10/05/2015] [Indexed: 02/05/2023]
Abstract
Ginkgo biloba extract is an alternative medicine available as a standardized formulation, EGb 761®, which consists of ginkgolides, bilobalide, and flavonoids. The individual constituents have varying therapeutic mechanisms that contribute to the pharmacological activity of the extract as a whole. Recent studies show anxiolytic properties of ginkgolide A, migraine with aura treatment by ginkgolide B, a reduction in ischemia-induced glutamate excitotoxicity by bilobalide, and an alternative antihypertensive property of quercetin, among others. These findings have been observed in EGb 761 as well and have led to clinical investigation into its use as a therapeutic for conditions such as cognition, dementia, cardiovascular, and cerebrovascular diseases. This review explores the therapeutic mechanisms of the individual EGb 761 constituents to explain the pharmacology as a whole and its clinical application to cardiovascular and neurological disorders, in particular ischemic stroke.
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Affiliation(s)
- Kevin M Nash
- Department of Pharmacology, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, OH, USA
| | - Zahoor A Shah
- Department of Pharmacology, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, OH, USA. ; Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, OH, USA
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62
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Guo XL, Chen JS. Research on induced pluripotent stem cells and the application in ocular tissues. Int J Ophthalmol 2015; 8:818-25. [PMID: 26309885 DOI: 10.3980/j.issn.2222-3959.2015.04.31] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 02/02/2015] [Indexed: 12/31/2022] Open
Abstract
Induced pluripotent stem cells (iPSCs) were firstly induced from mouse fibroblasts since 2006, and then the research on iPSCs had made great progress in the following years. iPSCs were established from different somatic cells through DNA, RNA, protein or small molecule pathways and transduction vehicles. With continuous improvement of technology on reprogramming, the induction of iPSCs became more secure and effective, and showed enormous promise for clinical applications. We reviewed different reprogramming of somatic cells, four kinds of pathways of reprogramming and three types of transduction vehicles, and discuss the research of iPSCs in ophthalmology and the prospect of iPSCs applications.
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Affiliation(s)
- Xiao-Ling Guo
- Key Laboratory for Regenerative Medicine, Ministry of Education, Jinan University, Guangzhou 510632, Guangdong Province, China
| | - Jian-Su Chen
- Key Laboratory for Regenerative Medicine, Ministry of Education, Jinan University, Guangzhou 510632, Guangdong Province, China ; Eye Institute, Medical College of Jinan University, Guangzhou 510632, Guangdong Province, China ; Department of Ophthalmology, the First Clinical Medical College of Jinan University, Guangzhou 510632, Guangdong Province, China
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63
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Sankavaram SR, Svensson MA, Olsson T, Brundin L, Johansson CB. Cell Fusion along the Anterior-Posterior Neuroaxis in Mice with Experimental Autoimmune Encephalomyelitis. PLoS One 2015. [PMID: 26207625 PMCID: PMC4514791 DOI: 10.1371/journal.pone.0133903] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Background It is well documented that bone marrow-derived cells can fuse with a diverse range of cells, including brain cells, under normal or pathological conditions. Inflammation leads to robust fusion of bone marrow-derived cells with Purkinje cells and the formation of binucleate heterokaryons in the cerebellum. Heterokaryons form through the fusion of two developmentally differential cells and as a result contain two distinct nuclei without subsequent nuclear or chromosome loss. Aim In the brain, fusion of bone marrow-derived cells appears to be restricted to the complex and large Purkinje cells, raising the question whether the size of the recipient cell is important for cell fusion in the central nervous system. Purkinje cells are among the largest neurons in the central nervous system and accordingly can harbor two nuclei. Results Using a well-characterized model for heterokaryon formation in the cerebellum (experimental autoimmune encephalomyelitis - a mouse model of multiple sclerosis), we report for the first time that green fluorescent protein-labeled bone marrow-derived cells can fuse and form heterokaryons with spinal cord motor neurons. These spinal cord heterokaryons are predominantly located in or adjacent to an active or previously active inflammation site, demonstrating that inflammation and infiltration of immune cells are key for cell fusion in the central nervous system. While some motor neurons were found to contain two nuclei, co-expressing green fluorescent protein and the neuronal marker, neuron-specific nuclear protein, a number of small interneurons also co-expressed green fluorescent protein and the neuronal marker, neuron-specific nuclear protein. These small heterokaryons were scattered in the gray matter of the spinal cord. Conclusion This novel finding expands the repertoire of neurons that can form heterokaryons with bone marrow-derived cells in the central nervous system, albeit in low numbers, possibly leading to a novel therapy for spinal cord motor neurons or other neurons that are compromised in the central nervous system.
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Affiliation(s)
- Sreenivasa R. Sankavaram
- Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Mikael A. Svensson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Tomas Olsson
- Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Lou Brundin
- Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Clas B. Johansson
- Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Public Dental Service at Gällö, Jämtland Härjedalen County Council, Gällö, Sweden
- * E-mail:
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64
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Shadrin IY, Yoon W, Li L, Shepherd N, Bursac N. Rapid fusion between mesenchymal stem cells and cardiomyocytes yields electrically active, non-contractile hybrid cells. Sci Rep 2015; 5:12043. [PMID: 26159124 PMCID: PMC4498233 DOI: 10.1038/srep12043] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 06/12/2015] [Indexed: 12/26/2022] Open
Abstract
Cardiac cell therapies involving bone marrow-derived human mesenchymal stem cells (hMSCs) have shown promising results, although their mechanisms of action are still poorly understood. Here, we investigated direct interactions between hMSCs and cardiomyocytes in vitro. Using a genetic Ca2+ indicator gCaMP3 to efficiently label hMSCs in co-cultures with neonatal rat ventricular myocytes (NRVMs), we determined that 25–40% of hMSCs (from 4 independent donors) acquired periodic Ca2+ transients and cardiac markers through spontaneous fusion with NRVMs. Sharp electrode and voltage-clamp recordings in fused cells showed action potential properties and Ca2+ current amplitudes in between those of non-fused hMSCs and NRVMs. Time-lapse video-microscopy revealed the first direct evidence of active fusion between hMSCs and NRVMs within several hours of co-culture. Application of blebbistatin, nifedipine or verapamil caused complete and reversible inhibition of fusion, suggesting potential roles for actomyosin bridging and Ca2+ channels in the fusion process. Immunostaining for Cx43, Ki67, and sarcomeric α-actinin showed that fused cells remain strongly coupled to surrounding NRVMs, but downregulate sarcomeric structures over time, acquiring a non-proliferative and non-contractile phenotype. Overall, these results describe the phenotype and mechanisms of hybrid cell formation via fusion of hMSCs and cardiomyocytes with potential implications for cardiac cell therapy.
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Affiliation(s)
- Ilya Y Shadrin
- Department of Biomedical Engineering, Duke University, Durham, NC
| | - Woohyun Yoon
- Department of Biomedical Engineering, Duke University, Durham, NC
| | - Liqing Li
- Department of Biomedical Engineering, Duke University, Durham, NC
| | - Neal Shepherd
- Department of Biomedical Engineering, Duke University, Durham, NC
| | - Nenad Bursac
- Department of Biomedical Engineering, Duke University, Durham, NC
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65
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Identification of myopia-associated WNT7B polymorphisms provides insights into the mechanism underlying the development of myopia. Nat Commun 2015; 6:6689. [DOI: 10.1038/ncomms7689] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 02/20/2015] [Indexed: 11/08/2022] Open
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66
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Jayakody SA, Gonzalez-Cordero A, Ali RR, Pearson RA. Cellular strategies for retinal repair by photoreceptor replacement. Prog Retin Eye Res 2015; 46:31-66. [PMID: 25660226 DOI: 10.1016/j.preteyeres.2015.01.003] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 01/13/2015] [Accepted: 01/19/2015] [Indexed: 02/08/2023]
Abstract
Loss of photoreceptors due to retinal degeneration is a major cause of blindness in the developed world. While no effective treatment is currently available, cell replacement therapy, using pluripotent stem cell-derived photoreceptor precursor cells, may be a feasible future treatment. Recent reports have demonstrated rescue of visual function following the transplantation of immature photoreceptors and we have seen major advances in our ability to generate transplantation-competent donor cells from stem cell sources. Moreover, we are beginning to realise the possibilities of using endogenous populations of cells from within the retina itself to mediate retinal repair. Here, we present a review of our current understanding of endogenous repair mechanisms together with recent progress in the use of both ocular and pluripotent stem cells for the treatment of photoreceptor loss. We consider how our understanding of retinal development has underpinned many of the recent major advances in translation and moved us closer to the goal of restoring vision by cellular means.
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Affiliation(s)
- Sujatha A Jayakody
- Gene and Cell Therapy Group, Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath St, London EC1V 9EL, UK
| | - Anai Gonzalez-Cordero
- Gene and Cell Therapy Group, Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath St, London EC1V 9EL, UK
| | - Robin R Ali
- Gene and Cell Therapy Group, Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath St, London EC1V 9EL, UK; NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK
| | - Rachael A Pearson
- Gene and Cell Therapy Group, Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath St, London EC1V 9EL, UK.
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67
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Patel AK, Surapaneni K, Yi H, Nakamura REI, Karli SZ, Syeda S, Lee T, Hackam AS. Activation of Wnt/β-catenin signaling in Muller glia protects photoreceptors in a mouse model of inherited retinal degeneration. Neuropharmacology 2014; 91:1-12. [PMID: 25486619 DOI: 10.1016/j.neuropharm.2014.11.015] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 11/13/2014] [Accepted: 11/19/2014] [Indexed: 11/18/2022]
Abstract
The canonical Wnt/β-catenin ("Wnt") pathway is an essential signaling cascade in the embryonic central nervous system (CNS) that regulates neuronal differentiation and survival. Loss of Wnt signaling in developing and adult tissue has been implicated in numerous CNS diseases, but the precise role of Wnt in regulating neuronal survival, and how its absence could lead to disease, is not understood. In this study, we investigated the effect of Wnt activation on neuronal survival in the adult retina, and identified cellular and molecular mediators. Pan-retinal Wnt signaling activation using Wnt3a induced functional and morphological rescue of photoreceptor neurons in the rd10 mouse model of retinal degeneration. Furthermore, Wnt activation using constitutively active β-catenin specifically targeted to Muller glia increased photoreceptor survival and reduced markers of glial and neuronal remodeling. Wnt-induced photoreceptor protection was associated with elevated levels of the prosurvival protein Stat3, and was reduced by shRNA-mediated knock-down of Stat3, indicating cross-talk between survival pathways. Therefore, these data increase our understanding of the role of Wnt signaling in the retina, and identify radial Muller glia as important cellular mediators of Wnt activity.
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Affiliation(s)
- Amit K Patel
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Krishna Surapaneni
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Hyun Yi
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Rei E I Nakamura
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Sapir Z Karli
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Sarah Syeda
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Tinthu Lee
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA
| | - Abigail S Hackam
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, USA.
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68
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Kemp K, Wilkins A, Scolding N. Cell fusion in the brain: two cells forward, one cell back. Acta Neuropathol 2014; 128:629-38. [PMID: 24899142 PMCID: PMC4201757 DOI: 10.1007/s00401-014-1303-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 05/21/2014] [Accepted: 05/25/2014] [Indexed: 01/30/2023]
Abstract
Adult stem cell populations, notably those which reside in the bone marrow, have been shown to contribute to several neuronal cell types in the rodent and human brain. The observation that circulating bone marrow cells can migrate into the central nervous system and fuse with, in particular, cerebellar Purkinje cells has suggested, at least in part, a potential mechanism behind this process. Experimentally, the incidence of cell fusion in the brain is enhanced with age, radiation exposure, inflammation, chemotherapeutic drugs and even selective damage to the neurons themselves. The presence of cell fusion, shown by detection of increased bi-nucleated neurons, has also been described in a variety of human central nervous system diseases, including both multiple sclerosis and Alzheimer’s disease. Accumulating evidence is therefore raising new questions into the biological significance of cell fusion, with the possibility that it represents an important means of cell-mediated neuroprotection or rescue of highly complex neurons that cannot be replaced in adult life. Here, we discuss the evidence behind this phenomenon in the rodent and human brain, with a focus on the subsequent research investigating the physiological mechanisms of cell fusion underlying this process. We also highlight how these studies offer new insights into endogenous neuronal repair, opening new exciting avenues for potential therapeutic interventions against neurodegeneration and brain injury.
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69
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Rakoczy EP, Narfström K. Gene therapy for eye as regenerative medicine? Lessons from RPE65 gene therapy for Leber's Congenital Amaurosis. Int J Biochem Cell Biol 2014; 56:153-7. [PMID: 25286304 DOI: 10.1016/j.biocel.2014.09.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 09/08/2014] [Accepted: 09/25/2014] [Indexed: 11/15/2022]
Abstract
Recombinant virus mediated gene therapy of Leber's Congenital Amaurosis has provided a wide range of data on the utility of gene replacement therapy for recessive diseases. Studies to date demonstrate that gene therapy in the eye is safe and can result in long-term recovery of visual function, but they also highlight that further research is required to identify optimum intervention time-points, target populations and the compatibility of associate therapies. This article is part of a directed issue entitled: Regenerative Medicine: the challenge of translation.
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Affiliation(s)
- Elizabeth P Rakoczy
- Centre for Ophthalmology and Visual Sciences, The University of Western Australia, Crawley, 6009, Western Australia, Australia.
| | - Kristina Narfström
- College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
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70
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Xie Y, Lu W, Liu S, Yang Q, Carver BS, Li E, Wang Y, Fazli L, Gleave M, Chen Z. Crosstalk between nuclear MET and SOX9/β-catenin correlates with castration-resistant prostate cancer. Mol Endocrinol 2014; 28:1629-39. [PMID: 25099011 DOI: 10.1210/me.2014-1078] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Castration-resistant prostate cancer (PCa) (CRPC) is relapse after various forms of androgen ablation therapy and causes a major mortality in PCa patients, yet the mechanism remains poorly understood. Here, we report the nuclear form of mesenchymal epithelial transition factor (nMET) is essential for CRPC. Specifically, nMET is remarkably increased in human CRPC samples compared with naïve samples. Androgen deprivation induces endogenous nMET and promotes cell proliferation and stem-like cell self-renewal in androgen-nonresponsive PCa cells. Mechanistically, nMET activates SRY (sex determining region Y)-box9, β-catenin, and Nanog homeobox and promotes sphere formation in the absence of androgen stimulus. Combined treatment of MET and β-catenin enhances the inhibition of PCa cell growth. Importantly, MET accumulation is detected in nucleus of recurrent prostate tumors of castrated Pten/Trp53 null mice, whereas MET elevation is predominantly found in membrane of naïve tumors. Our findings reveal for the first time an essential role of nMET association with SOX9/β-catenin in CRPC in vitro and in vivo, highlighting that nuclear RTK activate cell reprogramming to drive recurrence, and targeting nMET would be a new avenue to treat recurrent cancers.
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Affiliation(s)
- Yingqiu Xie
- Department of Biochemistry and Cancer Biology (Y.X., W.L., S.L., Q.Y., Z.C.), Meharry Medical College, Nashville, Tennessee 37208; Department of Surgery and Division of Urology (B.S.C.), Memorial Sloan-Kettering Cancer Center, New York, New York 10065; and Vancouver Prostate Centre and Department of Urologic Sciences (E.L., Y.W., L.F., M.G.), The University of British Columbia, Vancouver, British Columbia, Canada V6H 3Z6
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71
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Wright LS, Phillips MJ, Pinilla I, Hei D, Gamm DM. Induced pluripotent stem cells as custom therapeutics for retinal repair: progress and rationale. Exp Eye Res 2014; 123:161-72. [PMID: 24534198 PMCID: PMC4047146 DOI: 10.1016/j.exer.2013.12.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 10/25/2013] [Accepted: 12/02/2013] [Indexed: 12/17/2022]
Abstract
Human pluripotent stem cells have made a remarkable impact on science, technology and medicine by providing a potentially unlimited source of human cells for basic research and clinical applications. In recent years, knowledge gained from the study of human embryonic stem cells and mammalian somatic cell reprogramming has led to the routine production of human induced pluripotent stem cells (hiPSCs) in laboratories worldwide. hiPSCs show promise for use in transplantation, high throughput drug screening, "disease-in-a-dish" modeling, disease gene discovery, and gene therapy testing. This review will focus on the first application, beginning with a discussion of methods for producing retinal lineage cells that are lost in inherited and acquired forms of retinal degenerative disease. The selection of appropriate hiPSC-derived donor cell type(s) for transplantation will be discussed, as will the caveats and prerequisite steps to formulating a clinical Good Manufacturing Practice (cGMP) product for clinical trials.
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Affiliation(s)
- Lynda S Wright
- Waisman Center, University of Wisconsin, Madison, WI, USA; McPherson Eye Research Institute, University of Wisconsin, Madison, WI, USA
| | - M Joseph Phillips
- Waisman Center, University of Wisconsin, Madison, WI, USA; McPherson Eye Research Institute, University of Wisconsin, Madison, WI, USA
| | - Isabel Pinilla
- Department of Ophthalmology, Lozano Blesa Hospital and Aragones Health Sciences Institute, Zaragoza, Spain
| | - Derek Hei
- Waisman Center, University of Wisconsin, Madison, WI, USA
| | - David M Gamm
- Waisman Center, University of Wisconsin, Madison, WI, USA; McPherson Eye Research Institute, University of Wisconsin, Madison, WI, USA; Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI, USA.
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72
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Yu H, Vu THK, Cho KS, Guo C, Chen DF. Mobilizing endogenous stem cells for retinal repair. Transl Res 2014; 163:387-98. [PMID: 24333552 PMCID: PMC3976683 DOI: 10.1016/j.trsl.2013.11.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 11/18/2013] [Accepted: 11/19/2013] [Indexed: 02/06/2023]
Abstract
Irreversible vision loss is most often caused by the loss of function and subsequent death of retinal neurons, such as photoreceptor cells-the cells that initiate vision by capturing and transducing signals of light. One reason why retinal degenerative diseases are devastating is that, once retinal neurons are lost, they don't grow back. Stem cell-based cell replacement strategy for retinal degenerative diseases are leading the way in clinical trials of transplantation therapy, and the exciting findings in both human and animal models point to the possibility of restoring vision through a cell replacement regenerative approach. A less invasive method of retinal regeneration by mobilizing endogenous stem cells is, thus, highly desirable and promising for restoring vision. Although many obstacles remain to be overcome, the field of endogenous retinal repair is progressing at a rapid pace, with encouraging results in recent years.
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Affiliation(s)
- Honghua Yu
- Department of Ophthalmology, Liuhuaqiao Hospital, Guangzhou, PR China; Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Mass
| | - Thi Hong Khanh Vu
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Mass; Department of Ophthalmology, Leiden University Medical Center, Leiden, Netherlands
| | - Kin-Sang Cho
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Mass
| | - Chenying Guo
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Mass
| | - Dong Feng Chen
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Mass; VA Boston Healthcare System, Boston, Mass.
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Identification of age-related macular degeneration related genes by applying shortest path algorithm in protein-protein interaction network. BIOMED RESEARCH INTERNATIONAL 2013; 2013:523415. [PMID: 24455700 PMCID: PMC3878555 DOI: 10.1155/2013/523415] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 11/27/2013] [Indexed: 12/31/2022]
Abstract
This study attempted to find novel age-related macular degeneration (AMD) related genes based on 36 known AMD genes. The well-known shortest path algorithm, Dijkstra's algorithm, was applied to find the shortest path connecting each pair of known AMD related genes in protein-protein interaction (PPI) network. The genes occurring in any shortest path were considered as candidate AMD related genes. As a result, 125 novel AMD genes were predicted. The further analysis based on betweenness and permutation test indicates that there are 10 genes involved in the formation or development of AMD and may be the actual AMD related genes with high probability. We hope that this contribution would promote the study of age-related macular degeneration and discovery of novel effective treatments.
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