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Coroneo MT, Graterol-Nisi G, Maver E, Gillies RM. Aqueous Humor Circulation in the Era of Minimally Invasive Surgery for Glaucoma. Ann Biomed Eng 2024; 52:898-907. [PMID: 38155316 DOI: 10.1007/s10439-023-03427-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 12/11/2023] [Indexed: 12/30/2023]
Abstract
Glaucoma surgery with implantation of aqueous humor draining microstents may compromise long-term corneal health by disrupting aqueous humor circulation. The effect of stent numbers on this circulation was interrogated to determine the number of stents associated with minimal circulation disruption. An in vitro anterior eye model perfusion system was constructed with multiple exit ports. A 3-D model of the anterior eye was imported into ABAQUS CFD, analyzes were carried out for unsteady laminar flow and solved using Navier-Stokes equations. DT Vision Foundry was used to analyze velocity contour plot images. The field variable results output for the CFD model were fluid wall shear, fluid pressure and fluid velocity. In vitro, "aqueous" fluid flow is high through a single stent and "aqueous" stagnation is greatest in the quadrants 180° away. Increasing stent port numbers, results in an exponential decrease in the stagnant flow locations. High wall shear stress was seen in the single stent model and is markedly reduced after a second and subsequent stents are introduced. We identify two factors potentially contributing to corneal compromise post glaucoma drainage surgery: aqueous humor stagnation, remote to the stent site and higher exit flows imparting increased stent exit shear stress (particularly with a single stent). With 4 stents, there is minimal disruption of anterior chamber circulation (mimicking physiological conditions). Furthermore we propose that aqueous humor circulation disruption via the usual single-exit port approach disrupts aqueous humor circulation with long-term consequences for corneal health.
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Affiliation(s)
- Minas T Coroneo
- Ophthalmic Surgeons, 2 St Pauls St, Randwick, NSW, 2031, Australia.
- Department of Ophthalmology, Prince of Wales Hospital/University of New South Wales, Sydney, Australia.
| | | | - Eric Maver
- Ophthalmic Surgeons, 2 St Pauls St, Randwick, NSW, 2031, Australia
| | - R Mark Gillies
- Medical Device Research Australia Pty Ltd, Sydney, Australia
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2
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Nasehi R, Schieren J, Grannemann C, Palkowitz AL, Babendreyer A, Schwarz N, Aveic S, Ludwig A, Leube RE, Fischer H. Bioprinting-associated pulsatile hydrostatic pressure elicits a mild proinflammatory response in epi- and endothelial cells. BIOMATERIALS ADVANCES 2023; 147:213329. [PMID: 36801795 DOI: 10.1016/j.bioadv.2023.213329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 01/19/2023] [Accepted: 02/02/2023] [Indexed: 02/10/2023]
Abstract
During nozzle-based bioprinting, like inkjet and microextrusion, cells are subjected to hydrostatic pressure for up to several minutes. The modality of the bioprinting-related hydrostatic pressure is either constant or pulsatile depending on the technique. We hypothesized that the difference in the modality of hydrostatic pressure affects the biological response of the processed cells differently. To test this, we used a custom-made setup to apply either controlled constant or pulsatile hydrostatic pressure on endothelial and epithelial cells. Neither bioprinting procedure visibly altered the distribution of selected cytoskeletal filaments, cell-substrate adhesions, and cell-cell contacts in either cell type. In addition, pulsatile hydrostatic pressure led to an immediate increase of intracellular ATP in both cell types. However, the bioprinting-associated hydrostatic pressure triggered a pro-inflammatory response in only the endothelial cells, with an increase of interleukin 8 (IL-8) and a decrease of thrombomodulin (THBD) transcripts. These findings demonstrate that the settings adopted during nozzle-based bioprinting cause hydrostatic pressure that can trigger a pro-inflammatory response in different barrier-forming cell types. This response is cell-type and pressure-modality dependent. The immediate interaction of the printed cells with native tissue and the immune system in vivo might potentially trigger a cascade of events. Our findings, therefore, are of major relevance in particular for novel intra-operative, multicellular bioprinting approaches.
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Affiliation(s)
- Ramin Nasehi
- Department of Dental Materials and Biomaterials Research, RWTH Aachen University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Jana Schieren
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Templergraben 55, 52062 Aachen, Germany
| | - Caroline Grannemann
- Institute of Molecular Pharmacology, RWTH Aachen University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Alena L Palkowitz
- Department of Dental Materials and Biomaterials Research, RWTH Aachen University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Aaron Babendreyer
- Institute of Molecular Pharmacology, RWTH Aachen University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Nicole Schwarz
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Templergraben 55, 52062 Aachen, Germany
| | - Sanja Aveic
- Department of Dental Materials and Biomaterials Research, RWTH Aachen University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Andreas Ludwig
- Institute of Molecular Pharmacology, RWTH Aachen University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Rudolf E Leube
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Templergraben 55, 52062 Aachen, Germany
| | - Horst Fischer
- Department of Dental Materials and Biomaterials Research, RWTH Aachen University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany.
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3
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Affiliation(s)
- Zheng He
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, Australia
| | - Algis J Vingrys
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, Australia
| | - James A Armitage
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia E‐mail:
| | - Bang V Bui
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, Australia
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4
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Nafian F, Kamali Doust Azad B, Yazdani S, Rasaee MJ, Daftarian N. A lab-on-a-chip model of glaucoma. Brain Behav 2020; 10:e01799. [PMID: 32803874 PMCID: PMC7559618 DOI: 10.1002/brb3.1799] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 06/14/2020] [Accepted: 07/28/2020] [Indexed: 01/13/2023] Open
Abstract
AIMS We developed a glaucoma-on-a-chip model to evaluate the viability of retinal ganglion cells (RGCs) against high pressure and the potential effect of neuroprotection. METHODS A three-layered chip consisting of interconnecting microchannels and culture wells was designed and fabricated from poly-methyl methacrylate sheets. The bottom surface of the wells was modified by air plasma and coated with different membranes to provide a suitable extracellular microenvironment. RGCs were purified from postnatal Wistar rats by magnetic assisted cell sorting up to 70% and characterized by flow cytometry and immunocytochemistry. The cultured RGCs were exposed to normal (15 mmHg) or elevated pressure (33 mmHg) for 6, 12, 24, 36, and 48 hr, with and without adding brain-derived neurotrophic factor (BDNF) or a novel BDNF mimetic (RNYK). RESULTS Multiple inlet ports allow culture media and gas into the wells under elevated hydrostatic pressure. PDL/laminin formed the best supporting membrane. RGC survival rates were 85%, 78%, 70%, 67%, and 61% under normal pressure versus 40%, 22%, 18%, 12%, and 10% under high pressure at 6, 12, 24, 36, and 48 hr, respectively. BDNF and RNYK separately reduced RGC death rates about twofold under both normal and elevated pressures. CONCLUSION This model recapitulated the effects of elevated pressure over relatively short time periods and demonstrated the neuroprotective effects of BDNF and RNYK.
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Affiliation(s)
- Fatemeh Nafian
- Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Babak Kamali Doust Azad
- Department of Electronics, School of Electrical and Computer Engineering, Tehran University, Tehran, Iran
| | - Shahin Yazdani
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Ocular Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Javad Rasaee
- Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Narsis Daftarian
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Ocular Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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5
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Ha Y, Yoo HJ, Shin S, Jun SB. Hemispherical Microelectrode Array for Ex Vivo Retinal Neural Recording. MICROMACHINES 2020; 11:mi11050538. [PMID: 32466300 PMCID: PMC7281771 DOI: 10.3390/mi11050538] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 05/21/2020] [Accepted: 05/22/2020] [Indexed: 12/13/2022]
Abstract
To investigate the neuronal visual encoding process in the retina, researchers have performed in vitro and ex vivo electrophysiological experiments using animal retinal tissues. The microelectrode array (MEA) has become a key component in retinal experiments because it enables simultaneous neural recording from a population of retinal neurons. However, in most retinal experiments, it is inevitable that the retinal tissue is flattened on the planar MEA, becoming deformed from the original hemispherical shape. During the tissue deforming process, the retina is subjected to mechanical stress, which can induce abnormal physiological conditions. To overcome this problem, in this study, we propose a hemispherical MEA with a curvature that allows retinal tissues to adhere closely to electrodes without tissue deformation. The electrode array is fabricated by stretching a thin, flexible polydimethylsiloxane (PDMS) electrode layer onto a hemispherical substrate. To form micro patterns of electrodes, laser processing is employed instead of conventional thin-film microfabrication processes. The feasibility for neural recording from retinal tissues using this array is shown by conducting ex vivo retinal experiments. We anticipate that the proposed techniques for hemispherical MEAs can be utilized not only for ex vivo retinal studies but also for various flexible electronics.
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Affiliation(s)
- Yoonhee Ha
- Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea; (Y.H.); (H.-J.Y.)
| | - Hyun-Ji Yoo
- Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea; (Y.H.); (H.-J.Y.)
| | - Soowon Shin
- Department of Bioengineering, TODOC Co., Ltd., Seoul 08394, Korea;
| | - Sang Beom Jun
- Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea; (Y.H.); (H.-J.Y.)
- Department of Brain and Cognitive Sciences, Ewha Womans University, Seoul 03760, Korea
- Correspondence: ; Tel.: +82-2-3277-3892
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6
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Aires ID, Boia R, Rodrigues-Neves AC, Madeira MH, Marques C, Ambrósio AF, Santiago AR. Blockade of microglial adenosine A 2A receptor suppresses elevated pressure-induced inflammation, oxidative stress, and cell death in retinal cells. Glia 2019; 67:896-914. [PMID: 30667095 PMCID: PMC6590475 DOI: 10.1002/glia.23579] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 11/08/2018] [Accepted: 11/28/2018] [Indexed: 12/20/2022]
Abstract
Glaucoma is a retinal degenerative disease characterized by the loss of retinal ganglion cells and damage of the optic nerve. Recently, we demonstrated that antagonists of adenosine A2A receptor (A2A R) control retinal inflammation and afford protection to rat retinal cells in glaucoma models. However, the precise contribution of microglia to retinal injury was not addressed, as well as the effect of A2A R blockade directly in microglia. Here we show that blocking microglial A2A R prevents microglial cell response to elevated pressure and it is sufficient to protect retinal cells from elevated pressure-induced death. The A2A R antagonist SCH 58261 or the knockdown of A2A R expression with siRNA in microglial cells prevented the increase in microglia response to elevated hydrostatic pressure. Furthermore, in retinal neural cell cultures, the A2A R antagonist decreased microglia proliferation, as well as the expression and release of pro-inflammatory mediators. Microglia ablation prevented neural cell death triggered by elevated pressure. The A2A R blockade recapitulated the effects of microglia depletion, suggesting that blocking A2A R in microglia is able to control neurodegeneration in glaucoma-like conditions. Importantly, in human organotypic retinal cultures, A2A R blockade prevented the increase in reactive oxygen species and the morphological alterations in microglia triggered by elevated pressure. These findings place microglia as the main contributors for retinal cell death during elevated pressure and identify microglial A2A R as a therapeutic target to control retinal neuroinflammation and prevent neural apoptosis elicited by elevated pressure.
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Affiliation(s)
- Inês Dinis Aires
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal
| | - Raquel Boia
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal
| | - Ana Catarina Rodrigues-Neves
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal
| | - Maria Helena Madeira
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal
| | - Carla Marques
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal
| | - António Francisco Ambrósio
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal
| | - Ana Raquel Santiago
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal.,Association for Innovation and Biomedical Research on Light and Image (AIBILI), Coimbra, Portugal
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7
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Villena A, Díaz F, Vidal L, Moreno M, Garcĺa-Campos J, De Vargas IP. Study of the effects of ocular hypotensive drugs on number of neurons in the retinal ganglion layer in a rat experimental glaucoma. Eur J Ophthalmol 2018; 19:963-70. [DOI: 10.1177/112067210901900611] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Alicia Villena
- Department of Histology and Histopathology, School of Medicine, University of Málaga
| | - Florentina Díaz
- Department of Histology and Histopathology, School of Medicine, University of Málaga
| | - Lourdes Vidal
- Department of Histology and Histopathology, School of Medicine, University of Málaga
| | - Mercedes Moreno
- Department of Ophthalmology, School of Medicine, University of Málaga - Spain
| | - Jose Garcĺa-Campos
- Department of Ophthalmology, School of Medicine, University of Málaga - Spain
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8
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Rizzo MI, Greco A, De Virgilio A, Gallo A, Taverniti L, Fusconi M, Conte M, Pagliuca G, Turchetta R, de Vincentiis M. Glaucoma: recent advances in the involvement of autoimmunity. Immunol Res 2018; 65:207-217. [PMID: 27475096 DOI: 10.1007/s12026-016-8837-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Glaucomatous optic neuropathy is the most commonly acquired optic neuropathy encountered in clinical practice. It is the second leading cause of blindness globally, after cataracts, but it presents a greater public health challenge than cataracts, because the blindness it causes is irreversible. It has pathogenesis still largely unknown and no established cure. Alterations in serum antibody profiles, upregulation, and downregulation have been described, but it still remains elusive if the autoantibodies seen in glaucoma are an epiphenomenon or causative. Hypertension, diabetes, and hearing disorders also are associated. This review is a glaucoma update with focus about the recent advances in the last 15 years.
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Affiliation(s)
- Maria Ida Rizzo
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy.,Department of Surgical Science, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Antonio Greco
- Department of Surgical Science, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Armando De Virgilio
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy. .,Department of Surgical Science, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy.
| | - Andrea Gallo
- Otorhinolaryngology Section, Department of Medico-Surgical Sciences and Biotechnologies, ''Sapienza'' University of Rome, Corso della Repubblica, 79, 04100, Latina, LT, Italy
| | - Luciano Taverniti
- Ophthalmology Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Massimo Fusconi
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Michela Conte
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Giulio Pagliuca
- Otorhinolaryngology Section, Department of Medico-Surgical Sciences and Biotechnologies, ''Sapienza'' University of Rome, Corso della Repubblica, 79, 04100, Latina, LT, Italy
| | - Rosaria Turchetta
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Marco de Vincentiis
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
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9
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Tworkoski E, Glucksberg MR, Johnson M. The effect of the rate of hydrostatic pressure depressurization on cells in culture. PLoS One 2018; 13:e0189890. [PMID: 29315329 PMCID: PMC5760025 DOI: 10.1371/journal.pone.0189890] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 12/04/2017] [Indexed: 01/07/2023] Open
Abstract
Changes in hydrostatic pressure, at levels as low as 10 mm Hg, have been reported in some studies to alter cell function in vitro; however, other studies have found no detectable changes using similar methodologies. We here investigate the hypothesis that the rate of depressurization, rather than elevated hydrostatic pressure itself, may be responsible for these reported changes. Hydrostatic pressure (100 mm Hg above atmospheric pressure) was applied to bovine aortic endothelial cells (BAECs) and PC12 neuronal cells using pressurized gas for periods ranging from 3 hours to 9 days, and then the system was either slowly (~30 minutes) or rapidly (~5 seconds) depressurized. Cell viability, apoptosis, proliferation, and F-actin distribution were then assayed. Our results did not show significant differences between rapidly and slowly depressurized cells that would explain differences previously reported in the literature. Moreover, we found no detectable effect of elevated hydrostatic pressure (with slow depressurization) on any measured variables. Our results do not confirm the findings of other groups that modest increases in hydrostatic pressure affect cell function, but we are not able to explain their findings.
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Affiliation(s)
- Ellen Tworkoski
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States of America
| | - Matthew R. Glucksberg
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States of America
| | - Mark Johnson
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States of America
- Department of Mechanical Engineering, Northwestern University, Evanston, Illinois, United States of America
- Department of Ophthalmology, Northwestern University, Chicago, Illinois, United States of America
- * E-mail:
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10
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Saccà SC, Gandolfi S, Bagnis A, Manni G, Damonte G, Traverso CE, Izzotti A. From DNA damage to functional changes of the trabecular meshwork in aging and glaucoma. Ageing Res Rev 2016; 29:26-41. [PMID: 27242026 DOI: 10.1016/j.arr.2016.05.012] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 05/25/2016] [Accepted: 05/26/2016] [Indexed: 12/24/2022]
Abstract
Glaucoma is a degenerative disease of the eye. Both the anterior and posterior segments of the eye are affected, extensive damage being detectable in the trabecular meshwork and the inner retina-central visual pathway complex. Oxidative stress is claimed to be mainly responsible for molecular damage in the anterior chamber. Indeed, oxidation harms the trabecular meshwork, leading eventually to endothelial cell decay, tissue malfunction, subclinical inflammation, changes in the extracellular matrix and cytoskeleton, altered motility, reduced outflow facility and (ultimately) increased IOP. Moreover, free radicals are involved in aging and can be produced in the brain (as well as in the eye) as a result of ischemia, leading to oxidation of the surrounding neurons. Glaucoma-related cell death occurs by means of apoptosis, and apoptosis is triggered by oxidative stress via (a) mitochondrial damage, (b) inflammation, (c) endothelial dysregulation and dysfunction, and (d) hypoxia. The proteomics of the aqueous humor is significantly altered in glaucoma as a result of oxidation-induced trabecular damage. Those proteins whose aqueous humor levels are increased in glaucoma are biomarkers of trabecular meshwork impairment. Their diffusion from the anterior to the posterior segment of the eye may be relevant in the cascade of events triggering apoptosis in the inner retinal layers, including the ganglion cells.
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Affiliation(s)
- Sergio Claudio Saccà
- IRCCS San Martino University Hospital, Department of Neuroscience and Sense Organs, San Martino Hospital, Ophthalmology Unit, Viale Benedetto XV, 16132 Genoa, Italy.
| | - Stefano Gandolfi
- Ophthalmology Unit, Department of Biological, Biotechnological and Translational Sciences, University of Parma, Parma, Italy
| | - Alessandro Bagnis
- University of Genoa, Eye Clinic, Department of Neuroscience and Sense Organs, Viale Benedetto XV, 5, 16148 Genoa, Italy
| | - Gianluca Manni
- Dept. of Clinical Science and Translational Medicine, University Tor Vergata, Rome, Italy
| | - Gianluca Damonte
- Dept. of Experimental Medicine, Section of Biochemistry and Center of Excellence for Biomedical Research, University of Genoa, Viale Benedetto XV 1, 16132 Genoa, Italy
| | - Carlo Enrico Traverso
- University of Genoa, Eye Clinic, Department of Neuroscience and Sense Organs, Viale Benedetto XV, 5, 16148 Genoa, Italy
| | - Alberto Izzotti
- Mutagenesis Unit, IRCCS San Martino University Hospital, IST National Institute for Cancer Research, Department of Health Sciences, University of Genoa, Via A. Pastore 1, Genoa I-16132, Italy
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11
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Experimentally Induced Mammalian Models of Glaucoma. BIOMED RESEARCH INTERNATIONAL 2015; 2015:281214. [PMID: 26064891 PMCID: PMC4433635 DOI: 10.1155/2015/281214] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 12/01/2014] [Indexed: 11/17/2022]
Abstract
A wide variety of animal models have been used to study glaucoma. Although these models provide valuable information about the disease, there is still no ideal model for studying glaucoma due to its complex pathogenesis. Animal models for glaucoma are pivotal for clarifying glaucoma etiology and for developing novel therapeutic strategies to halt disease progression. In this review paper, we summarize some of the major findings obtained in various glaucoma models and examine the strengths and limitations of these models.
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12
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13
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Harch PG. Hyperbaric oxygen therapy for post-concussion syndrome: contradictory conclusions from a study mischaracterized as sham-controlled. J Neurotrauma 2013; 30:1995-9. [PMID: 24004322 DOI: 10.1089/neu.2012.2799] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Paul G Harch
- Department of Medicine, Louisiana State University School of Medicine , New Orleans, Louisiana
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14
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Bell K, Funke S, Pfeiffer N, Grus FH. Serum and antibodies of glaucoma patients lead to changes in the proteome, especially cell regulatory proteins, in retinal cells. PLoS One 2012; 7:e46910. [PMID: 23071659 PMCID: PMC3469602 DOI: 10.1371/journal.pone.0046910] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2012] [Accepted: 09/06/2012] [Indexed: 12/16/2022] Open
Abstract
Purpose Previous studies show significantly specifically changed autoantibody reactions against retinal antigens in the serum of glaucoma and ocular hypertension (OHT) patients in comparison to healthy people. As pathogenesis of glaucoma still is unknown the aim of this study was to analyze if the serum and antibodies of glaucoma patients interact with neuroretinal cells. Methods R28 cells were incubated with serum of patients suffering from primary open angle glaucoma (POAG), normal tension glaucoma (NTG) or OHT, POAG serum after antibody removal and serum from healthy people for 48 h under a normal or an elevated pressure of 15000 Pa (112 mmHg). RGC5 cells were additionally incubated with POAG antibodies under a normal pressure. Protein profiles of the R28 cells were measured with Seldi-Tof-MS, protein identification was performed with Maldi-TofTof-MS. Protein analysis of the RGC5 cells was performed with ESI-Orbitrap MS. Statistical analysis including multivariate statistics, variance component analysis as well as calculating Mahalanobis distances was performed. Results Highly significant changes of the complex protein profiles after incubation with glaucoma and OHT serum in comparison to healthy serum were detected, showing specific changes in the cells (e.g. Protein at 9192 Da (p<0.001)). The variance component analysis showed an effect of the serum of 59% on the cells. The pressure had an effect of 11% on the cells. Antibody removal led to significantly changed cell reactions (p<0.03). Furthermore, the incubation with POAG serum and its antibodies led to pro-apoptotic changes of proteins in the cells. Conclusions These studies show that the serum and the antibodies of glaucoma patients significantly change protein expressions involved in cell regulatory processes in neuroretinal cells. These could lead to a higher vulnerability of retinal cells towards stress factors such as an elevated IOP and eventually could lead to an increased apoptosis of the cells as in glaucoma.
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Affiliation(s)
- Katharina Bell
- Experimental Ophthalmology, Department of Ophthalmology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Sebastian Funke
- Experimental Ophthalmology, Department of Ophthalmology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Norbert Pfeiffer
- Experimental Ophthalmology, Department of Ophthalmology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Franz H. Grus
- Experimental Ophthalmology, Department of Ophthalmology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
- * E-mail:
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15
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Abstract
Apoptosis is a form of programmed cell death that is implicated in both pathological and physiological processes throughout the body. Its imaging in vivo with intravenous radiolabelled-annexin V has been heralded as an important advance, with around 30 clinical trials demonstrating its application in the early detection and monitoring of disease, and the assessment of efficacy of potential and existing therapies. A recent development has been the use of fluorescently labeled annexin V to visualize single retinal cells undergoing the process of apoptosis in vivo with ophthalmoscopy. This has been given the acronym DARC (Detection of Apoptosing Retinal Cells). DARC so far has only been used experimentally, but clinical trials are starting shortly in glaucoma patients. Results suggest that DARC may provide a direct assessment of retinal ganglion cell health. By enabling early assessment and quantitative analysis of cellular degeneration in glaucoma, it is hoped that DARC can identify patients before the onset of irreversible vision loss. Furthermore, in addition to aiding the tracking of disease, it may provide a rapid and objective assessment of potential and effective therapies, providing a new and meaningful clinical endpoint in glaucomatous disease that is so badly needed.
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Yu J, Zhong Y, Cheng Y, Shen X, Wang J, Wei Y. Effect of high hydrostatic pressure on the expression of glutamine synthetase in rat retinal Müller cells cultured in vitro. Exp Ther Med 2011; 2:513-516. [PMID: 22977533 DOI: 10.3892/etm.2011.239] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 03/16/2011] [Indexed: 11/05/2022] Open
Abstract
The aim of the present study was to examine the expression of glutamine synthetase (GS) in rat retinal Müller cells induced by different levels of hydrostatic pressure using a novel pressure mechanism. pH, PCO(2) or PO2 in culture medium as determined by gas analysis was used to examine the pressure mechanism. GS expression in the Müller cells at different levels of hydrostatic pressure (0, 20, 40, 60 and 80 mmHg/24 h) was examined using immunofluorescence, real-time PCR and Western blotting. There was no significant difference in pH, PCO(2) or PO(2) in the culture medium by gas analysis at the different hydrostatic pressure levels (p>0.05). Immunofluorescence staining showed that GS was expressed in the Müller cells. The expression of GS in the 40 mmHg/24 h and the 60 mmHg/24 h groups was increased significantly compared to that in the 0 mmHg/24 h group (p<0.05). These results suggest that the pressure mechanism which was constructed was effective and that moderate pressure promotes the up-regulation of GS in active Müller cells.
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Affiliation(s)
- Jun Yu
- Department of Ophthalmology, and
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Aldrete JA. Postoperative Deformities of the Dural Sac. Pain Manag 2011. [DOI: 10.1016/b978-1-4377-0721-2.00098-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Agarwal R, Gupta SK, Agarwal P, Saxena R, Agrawal SS. Current concepts in the pathophysiology of glaucoma. Indian J Ophthalmol 2009; 57:257-66. [PMID: 19574692 PMCID: PMC2712693 DOI: 10.4103/0301-4738.53049] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Accepted: 05/26/2008] [Indexed: 11/13/2022] Open
Abstract
Glaucoma, the second leading cause of blindness, is characterized by changes in the optic disc and visual field defects. The elevated intraocular pressure was considered the prime factor responsible for the glaucomatous optic neuropathy involving death of retinal ganglion cells and their axons. Extensive investigations into the pathophysiology of glaucoma now reveal the role of multiple factors in the development of retinal ganglion cell death. A better understanding of the pathophysiological mechanisms involved in the onset and progression of glaucomatous optic neuropathy is crucial in the development of better therapeutic options. This review is an effort to summarize the current concepts in the pathophysiology of glaucoma so that newer therapeutic targets can be recognized. The literature available in the National Medical Library and online Pubmed search engine was used for literature review.
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Affiliation(s)
- Renu Agarwal
- Department of Ocular Pharmacology, Delhi Institute of Pharmaceutical Sciences and Research, New Delhi, India
| | - Suresh K Gupta
- Department of Ocular Pharmacology, Delhi Institute of Pharmaceutical Sciences and Research, New Delhi, India
| | - Puneet Agarwal
- Department of Ocular Pharmacology, Delhi Institute of Pharmaceutical Sciences and Research, New Delhi, India
| | - Rohit Saxena
- Dr. Rajendra Prasad Center for Ophthalmic Sciences, New Delhi, India
| | - Shyam S Agrawal
- Department of Ocular Pharmacology, Delhi Institute of Pharmaceutical Sciences and Research, New Delhi, India
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Reigada D, Lu W, Zhang M, Mitchell CH. Elevated pressure triggers a physiological release of ATP from the retina: Possible role for pannexin hemichannels. Neuroscience 2008; 157:396-404. [PMID: 18822352 DOI: 10.1016/j.neuroscience.2008.08.036] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2008] [Revised: 07/26/2008] [Accepted: 08/19/2008] [Indexed: 01/16/2023]
Abstract
Increased hydrostatic pressure can damage neurons, although the mechanisms linking pressure to neurochemical imbalance or cell injury are not fully established. Throughout the body, mechanical perturbations such as shear stress, cell stretching, or changes in pressure can lead to excessive release of ATP. It is thus possible that increased pressure across neural tissues triggers an elevated release of ATP into extracellular space. As stimulation of the P2X(7) receptor for ATP on retinal ganglion cells leads to elevation of intracellular calcium and excitotoxic death, we asked whether increased levels of extracellular ATP accompanied an elevation in pressure across the retina. The hydrostatic pressure surrounding bovine retinal eyecups was increased and the ATP content of the vitreal compartment adjacent to the retina was determined. A step increase of only 20 mm Hg induced a threefold increase in the vitreal ATP concentration. The ATP levels correlated closely with the degree of pressure increase over 20-100 mm Hg. The increase was transient at lower pressures but sustained at higher pressures. The rise in vitreal ATP was the same regardless of whether nitrogen or air was used to increase pressure, implying changes in oxygen partial pressure did not contribute. Lactate dehydrogenase activity was not affected by pressure, ruling out a substantial contribution from cell lysis. The ATP increase was largely inhibited by either 30 muM 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) or 10 muM carbenoxolone (CBX). While this pharmacological profile is consistent with physiological release of ATP through pannexins hemichannels, a contribution from anion channels, vesicular release or other mechanisms cannot be ruled out. In conclusion, a step elevation in pressure leads to a physiologic increase in the levels of extracellular ATP bathing retinal neurons. This excess extracellular ATP may link increased pressure to the death of ganglion cells in acute glaucoma, and suggests a possible role for ATP in the neuronal damage accompanying increased intracranial pressure.
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Affiliation(s)
- D Reigada
- Department of Physiology, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104-6085, USA
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Zhong W, Xu C, Zhang F, Jiang X, Zhang X, Ye D. Cyclic stretching force-induced early apoptosis in human periodontal ligament cells. Oral Dis 2008; 14:270-6. [DOI: 10.1111/j.1601-0825.2007.01375.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Ishizaki K, Sakurai K, Tazaki M, Inoue T. Response of Merkel cells in the palatal rugae to the continuous mechanical stimulation by palatal plate. Somatosens Mot Res 2006; 23:63-72. [PMID: 16846961 DOI: 10.1080/08990220600741069] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The aim of the present study was to investigate the responses of Merkel cells that are numerous in the palatine rugae, due to the continuous mechanical stimulation exerted by the palatal plate. Forty golden hamsters were used in this experiment. The palatal plate was made of adhesive resin and it was set on the palate of the animal. To exert a continuous pressure, a 0.8 mm elevation on the internal surface of the palatal plate was created at the middle portion of the fourth palatine ruga. Thereafter, the number of Merkel cells in the mucosa was calculated by immunohistochemical observation. Morphological changes of Merkel cells were examined by electron microscopy. There was significant difference among the control and any of the treated groups on the number of CK20 positive Merkel cells (p < 0.05) and that numbers were decreased at the sites where continuous mechanical stimulation was exerted. Degeneration of the cytoplasm mitochondria and nerve endings, and a decrease in both the number of neurosecretory granules and cytoplasmic processes were observed. Furthermore, the presence of nuclear chromatin aggregation and fragmentation was recognized. The continuous mechanical stimulation by the palatal plate affected the responses of Merkel cells and nerve endings, thus inducing a decrease in the number of Merkel cells. A portion of these changes was also associated with the expression of apoptosis.
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Affiliation(s)
- Ken Ishizaki
- Department of Complete Denture Prosthodontics, Tokyo Dental College, Chiba, Japan
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Oka T, Tamada Y, Nakajima E, Shearer TR, Azuma M. Presence of calpain-induced proteolysis in retinal degeneration and dysfunction in a rat model of acute ocular hypertension. J Neurosci Res 2006; 83:1342-51. [PMID: 16528750 DOI: 10.1002/jnr.20827] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The purpose of this study was to determine if calpain-induced proteolysis was associated with retinal degeneration or dysfunction in the rat acute ocular hypertensive model. Acute glaucoma was produced by elevation of IOP to 120 mm Hg for 1 hr. Retinal degeneration was evaluated by H&E staining and apoptosis was determined by TUNEL staining in histologic sections of retina. Electroretinogram (ERG) was carried out to evaluate changes in functionality. Activation of calpains was determined by casein zymography and immunoblotting. Total calcium in retina was measured by atomic absorption spectrophotometry. Proteolysis of alpha-spectrin, tau, cdk5, and p35 (a regulator of cdk5) were evaluated by immunoblotting. The thickness of inner plexiform layer (IPL) and inner nuclear layer (INL), and the number of cells in the ganglion cell layer (GCL) decreased after ocular hypertension. Numerous cells in the INL stained positive for TUNEL and some cells in the outer nuclear layer (ONL) showed TUNEL staining. The a-wave in ERG was temporarily decreased after ocular hypertension and then recovered to normal. In contrast, the b-wave was completely lost. Calpains were activated after ocular hypertension. Activation of calpains was associated with increased calcium in retina. Calpain-dependent proteolysis of alpha-spectrin, tau, and p35 were observed in retina after ocular hypertension. The results suggested that increased calcium and subsequent proteolysis by activated calpains was associated with the death of inner retinal cells due to acute ocular hypertension in the rat model. Calpain inhibitors may be candidate drugs for treatment of retinal degeneration and dysfunction resulting from glaucoma.
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Affiliation(s)
- Takayuki Oka
- Kobe Creative Center, Senju Pharmaceutical Co., Ltd., Kobe, Hyogo, Japan
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Oka T, Walkup RD, Tamada Y, Nakajima E, Tochigi A, Shearer TR, Azuma M. Amelioration of retinal degeneration and proteolysis in acute ocular hypertensive rats by calpain inhibitor ((1S)-1-((((1S)-1-benzyl-3-cyclopropylamino-2,3-di-oxopropyl)amino)carbonyl)-3-methylbutyl)carbamic acid 5-methoxy-3-oxapentyl ester. Neuroscience 2006; 141:2139-45. [PMID: 16843603 DOI: 10.1016/j.neuroscience.2006.05.060] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Revised: 05/25/2006] [Accepted: 05/27/2006] [Indexed: 10/24/2022]
Abstract
BACKGROUND Our recent study suggested involvement of calpain-induced proteolysis in retinal degeneration and dysfunction in acute ocular hypertensive rats. The purpose of the present study was to determine if an orally available form of calpain inhibitor, ((1S)-1-((((1S)-1-benzyl-3-cyclopropylamino-2,3-di-oxopropyl)amino)carbonyl)-3-methylbutyl)carbamic acid 5-methoxy-3-oxapentyl ester (SNJ-1945), ameliorated retinal degeneration induced by acute hypertension in rats. To help extrapolate the effect of SNJ-1945 from the rat model to the human glaucomatous patient, in vitro inhibition of calpain-induced proteolysis by SNJ-1945 in monkey and human retinal proteins was compared with proteolysis in rat proteins. METHODS Intraocular pressure (IOP) in rats was elevated to 110 mm Hg for 50 min. SNJ-1945 was administrated i.p. or orally before ocular hypertension. Retinal degeneration was evaluated by hematoxylin and eosin (H&E) staining and cell counting. Transcripts for calpains and calpastatin in rat, monkey, and human retinas were measured by quantitative RT-PCR. Calpain activities were determined by casein zymography. Soluble retinal proteins from rat, monkey, and humans were incubated with calcium to activate calpains, with or without SNJ-1945. Proteolysis of calpain substrate alpha-spectrin was analyzed by immunoblotting. RESULTS Elevated IOP caused retinal degeneration and proteolysis of alpha-spectrin. Both i.p. and oral administration of SNJ-1945 inhibited proteolysis of alpha-spectrin and ameliorated retinal degeneration. Transcript levels for calpain 1 and calpastatin were similar in rat, monkey, and human retinas. Calpain 2 transcript levels were higher in rats compared with monkey and human. Appreciable caseinolytic activities due to calpains were observed in monkey and human retinas. Incubation of retinal soluble proteins with calcium led to proteolysis of alpha-spectrin due to calpains in rat, monkey, and human samples. SNJ-1945 similarly inhibited proteolysis in all species. CONCLUSION Our results suggested that orally available calpain inhibitor SNJ-1945 might be a possible candidate drug for testing in preventing progression of glaucomatous retinal degeneration.
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Affiliation(s)
- T Oka
- Kobe Creative Center, Senju Pharmaceutical Co., Ltd., 1-5-4 Murotani, Nishiku, Kobe, Hyogo 651-2241, Japan
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Ben Simon GJ, Bakalash S, Aloni E, Rosner M. A rat model for acute rise in intraocular pressure: immune modulation as a therapeutic strategy. Am J Ophthalmol 2006; 141:1105-11. [PMID: 16765680 DOI: 10.1016/j.ajo.2006.01.073] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2005] [Revised: 01/24/2006] [Accepted: 01/24/2006] [Indexed: 11/24/2022]
Abstract
PURPOSE To establish a rat model of acute increase in intraocular pressure (IOP) and to investigate the therapeutic window for protection against death of retinal ganglion cells (RGCs) by vaccination with glatiramer acetate (Cop-1) or by treatment with brimonidine or MK-801. DESIGN Animal study, laboratory investigation. METHODS IOP was transiently increased in anesthetized Lewis rats by infusing normal saline (0.9%) into the anterior chamber of the eye for one hour. RGC survival was assessed one week and two weeks later by counting the RGCs retrogradely labeled with rhodamine dextran. MAIN OUTCOME MEASURES RGC survival. RESULTS IOP rose to 100 cm H(2)O (76 mm Hg) and returned to baseline after 24 hours. The RGC count decreased by 23% a week after the insult and by a further 7% after the second week. Vaccination with Cop-1 on the day of the insult prevented 50% of the IOP-induced RGC loss. Similar neuroprotection was achieved by daily intraperitoneal injections of brimonidine, but not with MK-801. CONCLUSIONS A transient increase in IOP to 100 cm H(2)O causes death of RGCs in rats. A single immunization with Cop-1 or daily injections of brimonidine protected up to 50% of potentially doomed RGCs from IOP-induced death, suggesting that not all of the cell death in the untreated model results from the IOP insult directly, but that some of it is caused by insult-induced environmental cytotoxicity, which is unrelated to glutamate toxicity or at least to NMDA receptors. These findings can be applied immediately as a basis for acute glaucoma therapy.
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Affiliation(s)
- Guy J Ben Simon
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel.
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Agar A, Li S, Agarwal N, Coroneo MT, Hill MA. Retinal ganglion cell line apoptosis induced by hydrostatic pressure. Brain Res 2006; 1086:191-200. [PMID: 16638612 DOI: 10.1016/j.brainres.2006.02.061] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2005] [Revised: 02/09/2006] [Accepted: 02/13/2006] [Indexed: 11/26/2022]
Abstract
Cellular responses to changes in pressure are implicated in numerous disease processes. In glaucoma apoptosis of retinal ganglion cells (RGCs) is associated with elevated intra-ocular pressure, however, the exact cellular mechanisms remain unclear. We have previously shown that pressure can induce apoptosis in B35 and PC12 neuronal cell lines, using an in vitro model for pressure elevation. A novel RGC line allows us to study the effects of pressure on retinal neurons. 'RGC-5' cultures were subjected to elevated ambient hydrostatic pressure conditions in our model. Experimental pressure conditions were 100 mm Hg and 30 mm Hg, representing acute (high) and chronic (lower-pressure) glaucoma, and 15 mm Hg for normal intra-ocular pressure, set above atmospheric pressure for 2 h. Negative controls were treated identically except for the application of pressure, while positive controls were generated by treatment with a known apoptotic stimulus. Apoptosis was determined by a combination of cell morphology and specific TUNEL and Annexin V fluorescent markers. These were assessed simultaneously by laser scanning cytometry (LSC), which also enabled quantitative marker analysis. RGC-5 neurons showed a significantly increased proportion of apoptotic cells compared with controls; maximal at 100 mm Hg, moderate at 30 mm Hg and not statistically significant at 15 mm Hg. This graded response, proportionate to the level of pressure elevation, is representative of the severity of analogous clinical settings (acute, chronic glaucoma and normal). These results complement earlier findings of pressure-induced apoptosis in other neuronal cultures. They suggest the possibility of novel mechanisms of pressure-related mechanotransduction and cell death, relevant to the pathogenesis of diseases such as glaucoma.
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Affiliation(s)
- Ashish Agar
- Cell Biology Laboratory, School of Anatomy, University of New South Wales, Sydney, NSW, Australia
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Tan JCH, Kalapesi FB, Coroneo MT. Mechanosensitivity and the eye: cells coping with the pressure. Br J Ophthalmol 2006; 90:383-8. [PMID: 16488967 PMCID: PMC1856976 DOI: 10.1136/bjo.2005.079905] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The cells of the various organ systems in humans are subject to mechanical forces to which they must respond. Here the authors review what is known of the ways in which the cells of animals, ranging from the prokaryotic to humans, sense and transduce mechanical forces to respond to such stimuli. In what way this pertains to the eye, especially with respect to axial myopia and the pressure related disease of glaucoma, is then surveyed.
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Affiliation(s)
- J C H Tan
- Department of Ophthalmology, Prince of Wales Hospital, High Street, Randwick, NSW 2032, Australia
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Guo L, Moss SE, Alexander RA, Ali RR, Fitzke FW, Cordeiro MF. Retinal ganglion cell apoptosis in glaucoma is related to intraocular pressure and IOP-induced effects on extracellular matrix. Invest Ophthalmol Vis Sci 2005; 46:175-82. [PMID: 15623771 PMCID: PMC2601028 DOI: 10.1167/iovs.04-0832] [Citation(s) in RCA: 240] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
PURPOSE To investigate the effect of IOP on retinal ganglion cell (RGC) apoptosis and correlate the effects with IOP-induced changes in extracellular matrix (ECM) in the retina and optic nerve head (ONH) in glaucomatous rat eyes. METHODS Thirty-seven Dark Agouti rats had elevated IOP induced in the left eye by hypertonic saline episcleral vein injections. Eyes were examined at 3 months histologically for RGC apoptosis and expression of specific ECM components. RESULTS RGC apoptosis was significantly related to IOP exposure (integral DeltaIOP P <0.001; peak IOP P <0.01). In the RGC layer, elevated IOP correlated positively to a significant increase in MMP-9 activity (P <0.001), tissue inhibitor of matrix metalloproteinase (TIMP-1) (P <0.05), and collagen I (P <0.01), and negatively correlated to deposition of laminin (P <0.05) and TGF-beta2 (P <0.05). There was a significant correlation between MMP-9 activity and both RGC apoptosis (P <0.001) and loss of laminin (P <0.01). IOP exposure was also associated with increased deposition of TGF-beta2 and collagen I at the ONH (P <0.01). CONCLUSIONS The results demonstrated that RGC apoptosis in glaucoma correlates strongly with elevated IOP and is significantly associated with IOP-induced changes in specific ECM components in the RGC layer. The study shows for the first time a link between MMP-9, laminin degradation, RGC apoptosis, and IOP exposure in glaucoma. The findings suggest that abnormal ECM remodeling in the glaucomatous retina may relate to RGC death and support the notion that the retina is a primary site of injury in glaucoma.
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Affiliation(s)
- Li Guo
- Glaucoma and Optic Nerve Head Research Group, Department of Pathology, Institute of Ophthalmology, London, United Kingdom
| | - Stephen E. Moss
- Department of Cell Biology, Institute of Ophthalmology, London, United Kingdom
| | - Robert A. Alexander
- Glaucoma and Optic Nerve Head Research Group, Department of Pathology, Institute of Ophthalmology, London, United Kingdom
| | - Robin R. Ali
- Department of Molecular Genetics, Institute of Ophthalmology, London, United Kingdom
| | - Frederick W. Fitzke
- Visual Science Divisions, Institute of Ophthalmology, London, United Kingdom
| | - M. Francesca Cordeiro
- Glaucoma and Optic Nerve Head Research Group, Department of Pathology, Institute of Ophthalmology, London, United Kingdom
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Carvalho PSM, Tillitt DE. 2,3,7,8-TCDD effects on visual structure and function in swim-up rainbow trout. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2004; 38:6300-6306. [PMID: 15597885 DOI: 10.1021/es034857i] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
An understanding of mechanisms of contaminant effects across levels of biological organization is essential in ecotoxicology if we are to generate predictive models for population-level effects. We applied a suite of biochemical, histological, and behavioral end points related to visual structure and function and foraging behavior to evaluate effects of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) on swim-up rainbow trout. We detected a dose-dependent decrease in densities of retinal ganglion cells (RGC), key retinal neurons that link the eye with the brain. These changes resulted in corresponding deficits in visual/motor function including reductions in visual acuity and in scotopic and photopic thresholds due to TCDD. The loss of RGCs suggests an increase in convergence of synapses from photoreceptors to RGCs as a cellular mechanism for the visual deficits. Dose-dependent increases in immunohistochemical detection of CYP1A protein in the vasculature of the brain and eye choroid was proportional with decreased ganglion cell densities in the retina. TCDD-induced AHR-regulated effects on these tissues might be involved in the detected decrease in ganglion cell densities. Prey capture rate decreased after TCDD exposure only atthe highesttreatment groups evaluated. Collectively, these results show that TCDD causes biochemical and structural changes in the eye and brain of rainbow trout that are associated with behavioral deficits leading to decreased individual fitness.
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Affiliation(s)
- Paulo S M Carvalho
- Columbia Environmental Research Center, United States Geological Survey, Columbia, Missouri 65201, USA.
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Kountouras J, Zavos C, Chatzopoulos D. Induction of apoptosis as a proposed pathophysiological link between glaucoma and Helicobacter pylori infection. Med Hypotheses 2004; 62:378-81. [PMID: 14975507 DOI: 10.1016/j.mehy.2003.11.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2003] [Accepted: 11/11/2003] [Indexed: 10/26/2022]
Abstract
Although apoptosis is equally important both for the development and for the maintenance of homeostasis in some adult tissues, it can also be associated with disease processes. Current studies indicate that apoptosis is a mechanism of cell death in several important ocular and gastrointestinal diseases including glaucoma, and Helicobacter pylori (H. pylori)-induced upper gastrointestinal disorders and/or extraintestinal diseases, including autoimmune and neurodegenerative ones (Sjögren's syndrome, Guillain-Barre syndrome or Parkinson's disease). Glaucoma is also associated with similar autoimmune and neurodegenerative disorders, characterized by apoptotic loss of specific populations of neurons. Recently, a high prevalence of H. pylori infection has been recognized in patients with chronic open-angle glaucoma. In addition, H. pylori eradication may positively influence glaucoma parameters, thereby suggesting a possible causal link between H. pylori and glaucoma. H. pylori infection may influence the pathophysiology of glaucoma by releasing various proinflammatory and vasoactive substances, as well as by influencing apoptotic process; parameters that may also exert their own effects in the induction and/or progression of glaucomatous neuropathy. Importantly, H. pylori infection and glaucoma share the Fas/FasL and the mitochondria-mediated apoptotic pathways, thereby proposing an apoptotic link in the pathophysiology of both diseases.
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Affiliation(s)
- Jannis Kountouras
- Department of Gastroenterology, 2nd Medical Clinic, Ippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
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Cordeiro MF, Guo L, Luong V, Harding G, Wang W, Jones HE, Moss SE, Sillito AM, Fitzke FW. Real-time imaging of single nerve cell apoptosis in retinal neurodegeneration. Proc Natl Acad Sci U S A 2004; 101:13352-6. [PMID: 15340151 PMCID: PMC516570 DOI: 10.1073/pnas.0405479101] [Citation(s) in RCA: 191] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Apoptotic nerve cell death is implicated in the pathogenesis of several devastating neurodegenerative conditions, including glaucoma and Alzheimer's and Parkinson's diseases. We have devised a noninvasive real-time imaging technique using confocal laser-scanning ophthalmoscopy to visualize single nerve cell apoptosis in vivo, which allows longitudinal study of disease processes that has not previously been possible. Our method utilizes the unique optical properties of the eye, which allow direct microscopic observation of nerve cells in the retina. We have been able to image changes occurring in nerve cell apoptosis over hours, days, and months and show that effects depend on the magnitude of the initial apoptotic inducer in several models of neurodegenerative disease in rat and primate. This technology enables the direct observation of single nerve cell apoptosis in experimental neurodegeneration, providing the opportunity for detailed investigation of fundamental disease mechanisms and the evaluation of interventions with potential clinical applications, together with the possibility of taking this method through to patients.
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Affiliation(s)
- M Francesca Cordeiro
- Department of Pathology and Glaucoma and Optic Nerve Head Research Group, Institute of Ophthalmology, University College London, Bath Street, London EC1V 9EL, United Kingdom.
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Patwari P, Gaschen V, James IE, Berger E, Blake SM, Lark MW, Grodzinsky AJ, Hunziker EB. Ultrastructural quantification of cell death after injurious compression of bovine calf articular cartilage. Osteoarthritis Cartilage 2004; 12:245-52. [PMID: 14972342 PMCID: PMC2703677 DOI: 10.1016/j.joca.2003.11.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2003] [Accepted: 11/02/2003] [Indexed: 02/02/2023]
Abstract
OBJECTIVE It has been suggested that chondrocyte death by apoptosis may play a role in the pathogenesis of cartilage destruction in osteoarthritis, but the results of in-vivo and in-vitro investigations have been conflicting. To investigate further the cell death in our in-vitro model for traumatic joint injury, we performed a quantitative analysis by electron microscopy (EM) of cell morphology after injurious compression. For comparison, the TUNEL assay was also performed. DESIGN Articular cartilage explant disks were harvested from newborn calf femoropatellar groove. The disks were subjected to injurious compression (50% strain at a strain rate of 100%/s), incubated for 3 days, and then fixed for quantitative morphological analysis. RESULTS By TUNEL, the cell apoptosis rate increased from 7 +/- 2% in unloaded controls to 33 +/- 6% after injury (P=0.01; N=8 animals). By EM, the apoptosis rate increased from 5 +/- 1% in unloaded controls to 62 +/- 10% in injured cartilage (P=0.02, N=5 animals). Analysis by EM also identified that of the dead cells in injured disks, 97% were apoptotic by morphology. CONCLUSIONS These results confirm a significant increase in cell death after injurious compression and suggest that most cell death observed here was by an apoptotic process.
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Affiliation(s)
- P Patwari
- Continuum Electromechanics Lab, Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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Otey CA, Boukhelifa M, Maness P. B35 neuroblastoma cells: an easily transfected, cultured cell model of central nervous system neurons. Methods Cell Biol 2004; 71:287-304. [PMID: 12884695 DOI: 10.1016/s0091-679x(03)01013-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A panel of neuronal cell lines was derived from tumors of the neonatal rat central nervous system (CNS) in 1974, and two of these lines are in wide use today. Both the B35 and B50 lines offer a number of advantages to researchers who study CNS neurons in culture: they are simple to grow, to differentiate, and to transfect. B50 cells have been used extensively in the study of neuronal cell death, toxicology, and differentiation, whereas B35 cells have proven useful in the molecular analysis of endocytosis and of signaling pathways, in particular those that guide axonal outgrowth and cell motility. This chapter provides protocols for growing and transfecting B35 cells, selecting stable transfectants, exploring protein function using an antisense approach, and assaying cell motility in a Transwell chamber. All of these protocols have been written for researchers who have some skill in basic cell culture techniques, but previous experience with cultured neurons is not required.
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Affiliation(s)
- Carol A Otey
- Departments of Cell and Molecular Physiology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
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Dean JB, Mulkey DK, Garcia AJ, Putnam RW, Henderson RA. Neuronal sensitivity to hyperoxia, hypercapnia, and inert gases at hyperbaric pressures. J Appl Physiol (1985) 2003; 95:883-909. [PMID: 12909594 DOI: 10.1152/japplphysiol.00920.2002] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
As ambient pressure increases, hydrostatic compression of the central nervous system, combined with increasing levels of inspired Po2, Pco2, and N2 partial pressure, has deleterious effects on neuronal function, resulting in O2 toxicity, CO2 toxicity, N2 narcosis, and high-pressure nervous syndrome. The cellular mechanisms responsible for each disorder have been difficult to study by using classic in vitro electrophysiological methods, due to the physical barrier imposed by the sealed pressure chamber and mechanical disturbances during tissue compression. Improved chamber designs and methods have made such experiments feasible in mammalian neurons, especially at ambient pressures <5 atmospheres absolute (ATA). Here we summarize these methods, the physiologically relevant test pressures, potential research applications, and results of previous research, focusing on the significance of electrophysiological studies at <5 ATA. Intracellular recordings and tissue Po2 measurements in slices of rat brain demonstrate how to differentiate the neuronal effects of increased gas pressures from pressure per se. Examples also highlight the use of hyperoxia (<or=3 ATA O2) as a model for studying the cellular mechanisms of oxidative stress in the mammalian central nervous system.
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Affiliation(s)
- Jay B Dean
- Department of Anatomy and Physiology, Wright State University, Dayton, OH 45435, USA.
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Ishizaki K, Sakurai K, Tazaki Y, Tazaki M, Shimono M, Suzuki Y, Matsuzaka K, Inoue T. An Experimental Study on the Behavior of Merkel Cells under a Denture Base. ACTA ACUST UNITED AC 2003. [DOI: 10.2186/prp.2.59] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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