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Puñal VM, Paisley CE, Brecha FS, Lee MA, Perelli RM, Wang J, O’Koren EG, Ackley CR, Saban DR, Reese BE, Kay JN. Large-scale death of retinal astrocytes during normal development is non-apoptotic and implemented by microglia. PLoS Biol 2019; 17:e3000492. [PMID: 31626642 PMCID: PMC6821132 DOI: 10.1371/journal.pbio.3000492] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 10/30/2019] [Accepted: 09/26/2019] [Indexed: 12/28/2022] Open
Abstract
Naturally occurring cell death is a fundamental developmental mechanism for regulating cell numbers and sculpting developing organs. This is particularly true in the nervous system, where large numbers of neurons and oligodendrocytes are eliminated via apoptosis during normal development. Given the profound impact of death upon these two major cell populations, it is surprising that developmental death of another major cell type—the astrocyte—has rarely been studied. It is presently unclear whether astrocytes are subject to significant developmental death, and if so, how it occurs. Here, we address these questions using mouse retinal astrocytes as our model system. We show that the total number of retinal astrocytes declines by over 3-fold during a death period spanning postnatal days 5–14. Surprisingly, these astrocytes do not die by apoptosis, the canonical mechanism underlying the vast majority of developmental cell death. Instead, we find that microglia engulf astrocytes during the death period to promote their developmental removal. Genetic ablation of microglia inhibits astrocyte death, leading to a larger astrocyte population size at the end of the death period. However, astrocyte death is not completely blocked in the absence of microglia, apparently due to the ability of astrocytes to engulf each other. Nevertheless, mice lacking microglia showed significant anatomical changes to the retinal astrocyte network, with functional consequences for the astrocyte-associated vasculature leading to retinal hemorrhage. These results establish a novel modality for naturally occurring cell death and demonstrate its importance for the formation and integrity of the retinal gliovascular network. A study of the neonatal mouse retina shows that developmental cell death of retinal astrocytes does not occur by apoptosis but is instead mediated by microglia, which kill and engulf astrocytes to effect their developmental removal.
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Affiliation(s)
- Vanessa M. Puñal
- Department of Neurobiology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Caitlin E. Paisley
- Department of Neurobiology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Federica S. Brecha
- Department of Neurobiology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Monica A. Lee
- Department of Neurobiology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Robin M. Perelli
- Department of Neurobiology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Jingjing Wang
- Department of Neurobiology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Emily G. O’Koren
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States of America
- Department of Immunology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Caroline R. Ackley
- Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Department of Cellular, Molecular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Daniel R. Saban
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States of America
- Department of Immunology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Benjamin E. Reese
- Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Department of Psychological and Brain Sciences, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Jeremy N. Kay
- Department of Neurobiology, Duke University School of Medicine, Durham, North Carolina, United States of America
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States of America
- * E-mail:
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Simmons AB, Merrill MM, Reed JC, Deans MR, Edwards MM, Fuerst PG. Defective Angiogenesis and Intraretinal Bleeding in Mouse Models With Disrupted Inner Retinal Lamination. Invest Ophthalmol Vis Sci 2016; 57:1563-77. [PMID: 27046121 PMCID: PMC4824390 DOI: 10.1167/iovs.15-18395] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 01/31/2016] [Indexed: 01/09/2023] Open
Abstract
PURPOSE Abnormal retinal angiogenesis leads to visual impairment and blindness. Understanding how retinal vessels develop normally has dramatically improved treatments for people with retinal vasculopathies, but additional information about development is required. Abnormal neuron patterning in the outer retina has been shown to result in abnormal vessel development and blindness, for example, in people and mouse models with Crumbs homologue 1 (CRB1) mutations. In this study, we report and characterize a mouse model of inner retinal lamination disruption and bleeding, the Down syndrome cell adhesion molecule (Dscam) mutant, and test how neuron-neurite placement within the inner retina guides development of intraretinal vessels. METHODS Bax mutant mice (increased neuron cell number), Dscam mutant mice (increased neuron cell number, disorganized lamination), Fat3 mutant mice (disorganized neuron lamination), and Dscam gain-of-function mice (Dscam(GOF)) (decreased neuron cell number) were used to manipulate neuron placement and number. Immunohistochemistry was used to assay organization of blood vessels, glia, and neurons. In situ hybridization was used to map the expression of angiogenic factors. RESULTS Significant changes in the organization of vessels within mutant retinas were found. Displaced neurons and microglia were associated with the attraction of vessels. Using Fat3 mutant and Dscam(GOF) retinas, we provide experimental evidence that vessel branching is induced at the neuron-neurite interface, but that other factors are required for full plexus layer formation. We further demonstrate that the displacement of neurons results in the mislocalization of angiogenic factors. CONCLUSIONS Inner retina neuron lamination is required for development of intraretinal vessels.
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Affiliation(s)
- Aaron B. Simmons
- University of Idaho, Department of Biological Sciences, Moscow, Idaho, United States
| | - Morgan M. Merrill
- University of Idaho, Department of Biological Sciences, Moscow, Idaho, United States
| | - Justin C. Reed
- University of Washington School of Medicine, WWAMI Medical Education Program, Moscow, Idaho, United States
| | - Michael R. Deans
- University of Utah School of Medicine, Division of Otolaryngology–Head and Neck Surgery, Salt Lake City, Utah, United States
- University of Utah School of Medicine, Department of Neurobiology and Anatomy, Salt Lake City, Utah, United States
| | - Malia M. Edwards
- Johns Hopkins University School of Medicine, Wilmer Eye Institute, Baltimore, Maryland, United States
| | - Peter G. Fuerst
- University of Idaho, Department of Biological Sciences, Moscow, Idaho, United States
- University of Washington School of Medicine, WWAMI Medical Education Program, Moscow, Idaho, United States
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Morken TS, Nyman AKG, Sandvig I, Torp SH, Skranes J, Goa PE, Brubakk AM, Widerøe M. Brain development after neonatal intermittent hyperoxia-hypoxia in the rat studied by longitudinal MRI and immunohistochemistry. PLoS One 2013; 8:e84109. [PMID: 24358332 PMCID: PMC3866165 DOI: 10.1371/journal.pone.0084109] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 11/12/2013] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Neonatal intermittent hyperoxia-hypoxia (IHH) is involved in the pathogenesis of retinopathy of prematurity. Whether similar oxygen fluctuations will create pathological changes in the grey and white matter of the brain is unknown. METHODS From birth until postnatal day 14 (P14), two litters (total n = 22) were reared in IHH: hyperoxia (50% O2) interrupted by three consecutive two-minute episodes of hypoxia (12% O2) every sixth hour. Controls (n = 8) were reared in room-air (20.9% O2). Longitudinal MRI (Diffusion Tensor Imaging and T2-mapping) was performed on P14 and P28 and retinal and brain tissue were examined for histopathological changes. Long-term neurodevelopment was assessed on P20 and P27. RESULTS Mean, radial and axial diffusivity were higher in white matter of IHH versus controls at P14 (p < 0.04), while fractional anisotropy (FA) was lower in the hippocampal fimbria and tended to be lower in corpus callosum (p = 0.08) and external capsule (p = 0.05). White matter diffusivity in IHH was similar to controls at P28. Higher cortical vessel density (p = 0.005) was observed at P14. Cortical and thalamic T2-relaxation time and mean diffusivity were higher in the IHH group at P14 (p ≤ 0.03), and albumin leakage was present at P28. Rats in the IHH group ran for a longer time on a Rotarod than the control group (p ≤ 0.005). Pups with lower bodyweight had more severe MRI alterations and albumin leakage. CONCLUSION IHH led to subtle reversible changes in brain white matter diffusivity, grey matter water content and vascular density. However, alterations in blood-brain barrier permeability may point to long-term effects. The changes seen after IHH exposure were more severe in animals with lower bodyweight and future studies should aim at exploring possible interactions between IHH and growth restriction.
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Affiliation(s)
- Tora Sund Morken
- Department of Laboratory Medicine, Children’s and Women’s Health, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Axel Karl Gottfrid Nyman
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | - Ioanna Sandvig
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | - Sverre Helge Torp
- Department of Laboratory Medicine, Children’s and Women’s Health, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Jon Skranes
- Department of Laboratory Medicine, Children’s and Women’s Health, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- Department of Pediatrics, St. Olav University Hospital, Central Norway Regional Health Authority, Trondheim, Norway
| | - Pål Erik Goa
- Department of Radiology, St. Olav University Hospital, Central Norway Regional Health Authority, Trondheim, Norway
| | - Ann-Mari Brubakk
- Department of Laboratory Medicine, Children’s and Women’s Health, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- Department of Pediatrics, St. Olav University Hospital, Central Norway Regional Health Authority, Trondheim, Norway
| | - Marius Widerøe
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
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Notomi S, Hisatomi T, Murakami Y, Terasaki H, Sonoda S, Asato R, Takeda A, Ikeda Y, Enaida H, Sakamoto T, Ishibashi T. Dynamic increase in extracellular ATP accelerates photoreceptor cell apoptosis via ligation of P2RX7 in subretinal hemorrhage. PLoS One 2013; 8:e53338. [PMID: 23308196 PMCID: PMC3540091 DOI: 10.1371/journal.pone.0053338] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2012] [Accepted: 11/27/2012] [Indexed: 02/05/2023] Open
Abstract
Photoreceptor degeneration is the most critical cause of visual impairment in age-related macular degeneration (AMD). In neovascular form of AMD, severe photoreceptor loss develops with subretinal hemorrhage due to choroidal neovascularization (CNV), growth of abnormal blood vessels from choroidal circulation. However, the detailed mechanisms of this process remain elusive. Here we demonstrate that neovascular AMD with subretinal hemorrhage accompanies a significant increase in extracellular ATP, and that extracellular ATP initiates neurodegenerative processes through specific ligation of Purinergic receptor P2X, ligand-gated ion channel, 7 (P2RX7; P2X7 receptor). Increased extracellular ATP levels were found in the vitreous samples of AMD patients with subretinal hemorrhage compared to control vitreous samples. Extravascular blood induced a massive release of ATP and photoreceptor cell apoptosis in co-culture with primary retinal cells. Photoreceptor cell apoptosis accompanied mitochondrial apoptotic pathways, namely activation of caspase-9 and translocation of apoptosis-inducing factor (AIF) from mitochondria to nuclei, as well as TUNEL-detectable DNA fragmentation. These hallmarks of photoreceptor cell apoptosis were prevented by brilliant blue G (BBG), a selective P2RX7 antagonist, which is an approved adjuvant in ocular surgery. Finally, in a mouse model of subretinal hemorrhage, photoreceptor cells degenerated through BBG-inhibitable apoptosis, suggesting that ligation of P2RX7 by extracellular ATP may accelerate photoreceptor cell apoptosis in AMD with subretinal hemorrhage. Our results indicate a novel mechanism that could involve neuronal cell death not only in AMD but also in hemorrhagic disorders in the CNS and encourage the potential application of BBG as a neuroprotective therapy.
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Affiliation(s)
- Shoji Notomi
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Toshio Hisatomi
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
- Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan
| | - Yusuke Murakami
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hiroto Terasaki
- Department of Ophthalmology, Graduate School of Medical Sciences, Kagoshima University, Kagoshima, Japan
| | - Shozo Sonoda
- Department of Ophthalmology, Graduate School of Medical Sciences, Kagoshima University, Kagoshima, Japan
| | - Ryo Asato
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
- Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan
| | - Atsunobu Takeda
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yasuhiro Ikeda
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hiroshi Enaida
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Taiji Sakamoto
- Department of Ophthalmology, Graduate School of Medical Sciences, Kagoshima University, Kagoshima, Japan
| | - Tatsuro Ishibashi
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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Zhu Q, Ziemssen F, Henke-Fahle S, Tatar O, Szurman P, Aisenbrey S, Schneiderhan-Marra N, Xu X, Grisanti S. Vitreous levels of bevacizumab and vascular endothelial growth factor-A in patients with choroidal neovascularization. Ophthalmology 2008; 115:1750-5, 1755.e1. [PMID: 18708261 DOI: 10.1016/j.ophtha.2008.04.023] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Revised: 04/15/2008] [Accepted: 04/16/2008] [Indexed: 12/21/2022] Open
Abstract
PURPOSE To investigate the vitreous levels of bevacizumab and vascular endothelial growth factor-A (VEGF-A) after intravitreal injection of the drug in patients with choroidal neovascularization (CNV). DESIGN Interventional case series. PARTICIPANTS Eleven eyes of 11 patients with submacular hemorrhage and CNV due to age-related macular degeneration (n = 10) or angioid streaks (n = 1). METHODS All patients were treatment naïve except for a single dose of intravitreal injection of bevacizumab (1.25 mg/50 muL dose) and subsequent vitrectomy after various intervals (1-101 days) because of active and progressive lesion. Intravitreal free bevacizumab and VEGF-A levels were measured using enzyme-linked immunosorbent assay and microsphere-based immunoassay, respectively. Vitreous VEGF-A isoforms were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and Western blotting. MAIN OUTCOME MEASURES Intravitreal bevacizumab and VEGF-A levels were measured and pharmacokinetic parameters were calculated. RESULTS Pharmacokinetics of intravitreal bevacizumab followed a 2-compartment model with initial and terminal half-lives of 0.5 and 6.7 days, respectively. Bevacizumab could be detected in all cases, ranging from 2.63 ng/ml to 165 microg/ml. The peak concentration was observed on the second day after intravitreal bevacizumab injection. Vitreous free VEGF-A levels ranged from 0.2 to 33.9 pg/ml and showed a negative correlation with the bevacizumab concentration (P<0.001; r = -0.955) and a positive correlation with time (P<0.001; r = 0.964). However, the percentage expression of VEGF-A(165) exhibited a positive correlation with the bevacizumab concentration (P = 0.032, r = 0.645) and a negative correlation with time (P = 0.007, r = -0.755). A time-dependent increase was found for the percentage expression of VEGF-A(189) (P = 0.023, r = 0.673). Neither bevacizumab- nor time-related alterations were found for VEGF-A(121). CONCLUSIONS Based on pharmacokinetics, the interval of 6-7 weeks would be appropriate for efficacy, although clinical trials should guide dosing recommendations. Vitreous levels of free VEGF-A showed a negative correlation with the bevacizumab concentration, which confirmed the in vivo binding affinity of bevacizumab to VEGF-A. The analysis of the VEGF-A isoforms suggests differences of interaction between bevacizumab and individual VEGF-A isoforms.
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Affiliation(s)
- Qi Zhu
- Centre for Ophthalmology, Eberhard-Karls University, University Eye Hospital, Tübingen, Germany
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6
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Soliman W, Lund-Andersen H, Larsen M. Resolution of subretinal haemorrhage and fluid after intravitreal bevacizumab in aggressive peripapillary subretinal neovascularization. ACTA ACUST UNITED AC 2006; 84:707-8. [PMID: 16965507 DOI: 10.1111/j.1600-0420.2006.00736.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Wael Soliman
- Department of Ophthalmology, Herlev Hospital, University of Copenhagen, Herlev, Denmark.
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Kamei M, Misono K, Lewis H. A study of the ability of tissue plasminogen activator to diffuse into the subretinal space after intravitreal injection in rabbits. Am J Ophthalmol 1999; 128:739-46. [PMID: 10612511 DOI: 10.1016/s0002-9394(99)00239-1] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE Intravitreal injections of tissue plasminogen activator have been used to lyse fibrin from blood in the subretinal space, despite the lack of proof that tissue plasminogen activator can diffuse across the retina. We tested whether tissue plasminogen activator injected into the vitreous could penetrate the neural retina and enter the subretinal space. METHODS We injected a mixture of 50 microg of tissue plasminogen activator (70 kD) labeled with fluorescein isothiocyanate and rhodamine B isothiocyanate-labeled dextran, which has a lower molecular weight (20 kD), into the midvitreous cavity of one eye in each of 18 rabbits. The eyes were enucleated after 3, 6, and 24 hours, and cryosections were examined with epifluorescent microscopy to determine the distribution of the labeled molecules. We also evaluated tissue plasminogen activator pharmacokinetics in one eye each of 18 rabbits in which a subretinal clot was induced by injecting autologous blood (50 microL) into the subretinal space through the sclera. Fluorescein isothiocyanate-labeled tissue plasminogen activator was injected into the vitreous 2 days after induction of the subretinal clot. RESULTS Fluorescein isothiocyanate-labeled tissue plasminogen activator was present at the vitreal surface of the retina in a linear array in all 36 eyes studied, whereas the rhodamine B isothiocyanate-labeled dextran had diffused throughout the neural retina in the same sections. No fluorescein isothiocyanate signal was observed in the neural retina or in the subretinal clot. Vitreous hemorrhage caused by retinal perforation was observed in all eyes with intraretinal hemorrhage in which fluorescein isothiocyanate fluorescence was seen in the neural retina and inside the clot. CONCLUSION Intravitreal tissue plasminogen activator did not diffuse through the intact neural retina to reach a subretinal clot. This study demonstrates no scientific rationale for the intravitreal tissue plasminogen activator treatment of submacular hemorrhage without vitreous hemorrhage presumably caused by an overlying retinal break.
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Affiliation(s)
- M Kamei
- Cole Eye Institute and Division of Ophthalmology, The Cleveland Clinic Foundation, Ohio 44195, USA
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8
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Ito T, Nakano M, Yamamoto Y, Hiramitsu T, Mizuno Y. Hemoglobin-induced lipid peroxidation in the retina: a possible mechanism for macular degeneration. Arch Biochem Biophys 1995; 316:864-72. [PMID: 7864645 DOI: 10.1006/abbi.1995.1116] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
To investigate a possible link between subretinal hemorrhage and macular degeneration, oxyhemoglobin (HbO2) or methemoglobin (metHb) was incubated with retinal homogenate and unsaturated phospholipid peroxidation was monitored by (a) assay of thiobarbituric acid-reactive substances (TBARS), (b) luminescence originating from an energy transfer of lipid-degraded products to rose bengal, and (c) the decrease in composition of highly unsaturated fatty acids of phospholipids. TBARS formation and rose bengal luminescence in the case of metHb-induced lipid peroxidation were about 1.5 times greater than those in HbO2-induced lipid peroxidation. alpha-Tocopherol, a lipid-soluble antioxidant, and docosahexaenoic acid, a major unsaturated fatty acid, were slightly more rapidly decomposed after a 60-min incubation with metHb than with HbO2 at the same concentration. Atomic absorption analysis revealed that an equal concentration of iron was released from both HbO2 and metHb during incubation with retinal homogenates. The released iron may promote microsomal phospholipid peroxidation in the presence of endogenous ascorbate or NADPH-dependent cytochrome P-450 reductase because ascorbate oxidase and p-chloromercuribenzoic acid (an inhibitor of sulfhydryl enzymes) inhibited metHb- or HbO2-induced lipid peroxidation. MetHb-induced lipid peroxidation in retina was inhibited by KCN or NaN3, which binds to FeIII of metHb. KCN or NaN3 had no effect on HbO2-induced lipid peroxidation, because conversion of HbO2 to metHb, which can proceed in HbO2 incubated with phospholipid liposome, did not occur in retinal homogenates. It is concluded that metHb induces peroxidation of retinal unsaturated phospholipids (1) directly and (2) by releasing iron.
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Affiliation(s)
- T Ito
- Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan
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Murata T, Ishibashi T, Inomata H. Immunohistochemical detection of extravasated fibrinogen (fibrin) in human diabetic retina. Graefes Arch Clin Exp Ophthalmol 1992; 230:428-31. [PMID: 1521807 DOI: 10.1007/bf00175927] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
In diabetic retinopathy, breakdown of the blood-retinal barrier is an early functional disorder that can cause retinal edema, which in turn results in visual disturbance. Hard exudates, composed mainly of lipid and proteinaceous material, are one sign of chronic retinal edema caused by long-standing leakage from the vessels due to breakdown of the blood-retinal barrier. Utilizing diabetic retinas in which hard exudates were present, we performed immunohistochemical staining for fibrinogen. Because fibrinogen is a serum protein, its extravascular localization implies the existence of blood-retinal barrier breakdown. Our studies showed that the extravasated fibrinogen from blood-retinal barrier breakdown accumulated in the hard exudates and in areas of hemorrhage found primarily in the outer plexiform layer and was then phagocytosed by macrophages.
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Affiliation(s)
- T Murata
- Department of Ophthalmology, Faculty of Medicine, Kyushu University, Fukuoka, Japan
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10
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Abstract
Four patients with a central retinal vein obstruction associated with excessive deposits of hard exudate are described. When compared with a control group of 15 consecutive patients with a central retinal vein obstruction, those with large amounts of hard exudate were noted to have significantly elevated triglyceride levels, poorer visual acuity, and increased degrees of retinal ischemia on fluorescein angiography.
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Affiliation(s)
- G C Brown
- Retina Vascular Unit, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pa
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11
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Zirm M, Egger-Büssing C. [Protein glaucoma, a formerly unknown form of glaucoma]. Fortschr Med 1981; 99:862-3. [PMID: 7262765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
As a possible reason for a secondary glaucoma generally an unphysiological aggregation of proteins or blood in the aqueous humor is discussed. A positive Tyndall-phenomenon shows an increase of proteins in aqueous humor. We were able to demonstrate earlier that a negative Tyndall-phenomenon does not exclude this as well. In this contribution examples are given that disruption of vessel-membranes in retina and uvea lead to an increase of low molecular proteins in aqueous humor. Contrary to current knowledge we found that an overtaxing of active flow mechanisms by these additional proteins can cause a so-called protein-glucoma.
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12
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Mishra RK, Ghosh M, Ghosh A. Cholesterol crystals in Eales' disease. Indian J Ophthalmol 1980; 28:67-8. [PMID: 7216349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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13
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Bagrov SN, Glinchuk II. [Localization of retinal blood proteins in experimental intravitreous hemorrhages]. Vestn Oftalmol 1978:69-71. [PMID: 636160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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14
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Yeung J, Harris GS. Coats' disease: A study of cholesterol transport in the eye. Can J Ophthalmol 1976; 11:61-8. [PMID: 1247941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
An attempt to establish an animal model (rabbit) to study deposition and transport of cholesterol in the eye has been described. Interesting findings include the deposition of cholesterol in the choroid, sclera, and anterior cornea of rabbits fed on a high cholesterol diet. Injected intravitreal cholesterol is seen to leave through the retina, optic nerve head, and the trabecular meshwork. This process appears to be very slow. During the 4 months of observation the yellow preretinal deposits decreased little in size. Only 1 rabbit showed a picture typical of Coats' disease with serous detachment of the retina, subretinal lipoidal deposits and preretinal neovascularization. Although these results are preliminary, they suggest that fatty materials may pass through the retina into the subretinal space from the vitreous and might explain the pathogenesis of Coats' disease in the human.
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15
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Finley JK. Coats' disease. Am J Ophthalmol 1973; 76:401-2. [PMID: 4125597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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