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Mireles-Ramírez MA, Pacheco-Moises FP, González-Usigli HA, Sánchez-Rosales NA, Hernández-Preciado MR, Delgado-Lara DLC, Hernández-Cruz JJ, Ortiz GG. Neuromyelitis optica spectrum disorder: pathophysiological approach. Int J Neurosci 2024; 134:826-838. [PMID: 36453541 DOI: 10.1080/00207454.2022.2153046] [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: 03/12/2022] [Revised: 11/19/2022] [Accepted: 11/24/2022] [Indexed: 12/02/2022]
Abstract
Aim: To review the main pathological findings of Neuromyelitis Optica Spectrum Disorder (NMOSD) associated with the presence of autoantibodies to aquaporin-4 (AQP4) as well as the mechanisms of astrocyte dysfunction and demyelination. Methods: An comprehensive search of the literature in the field was carried out using the database of The National Center for Biotechnology Information from . Systematic searches were performed until July 2022. Results: NMOSD is an inflammatory and demyelinating disease of the central nervous system mainly in the areas of the optic nerves and spinal cord, thus explaining mostly the clinical findings. Other areas affected in NMOSD are the brainstem, hypothalamus, and periventricular regions. Relapses in NMOSD are generally severe and patients only partially recover. NMOSD includes clinical conditions where autoantibodies to aquaporin-4 (AQP4-IgG) of astrocytes are detected as well as similar clinical conditions where such antibodies are not detected. AQP4 are channel-forming integral membrane proteins of which AQ4 isoforms are able to aggregate in supramolecular assemblies termed orthogonal arrays of particles (OAP) and are essential in the regulation of water homeostasis and the adequate modulation of neuronal activity and circuitry. AQP4 assembly in orthogonal arrays of particles is essential for AQP4-IgG pathogenicity since AQP4 autoantibodies bind to OAPs with higher affinity than for AQP4 tetramers. NMOSD has a complex background with prominent roles for genes encoding cytokines and cytokine receptors. AQP4 autoantibodies activate the complement-mediated inflammatory demyelination and the ensuing damage to AQP4 water channels, leading to water influx, necrosis and axonal loss. Conclusions: NMOSD as an astrocytopathy is a nosological entity different from multiple sclerosis with its own serological marker: immunoglobulin G-type autoantibodies against the AQP4 protein which elicits a complement-dependent cytotoxicity and neuroinflammation. Some patients with typical manifestations of NMSOD are AQP4 seronegative and myelin oligodendrocyte glycoprotein positive. Thus, the detection of autoantibodies against AQP4 or other autoantibodies is crucial for the correct treatment of the disease and immunosuppressant therapy is the first choice.
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Affiliation(s)
- Mario A Mireles-Ramírez
- Department of Neurology, High Specialty Medical Unit, Western National Medical Center of the Mexican Institute of Social Security, Guadalajara, Jalisco, Mexico
| | - Fermín P Pacheco-Moises
- Department of Chemistry, University Center of Exact Sciences and Engineering; University of Guadalajara, Guadalajara, Jalisco, Mexico
| | - Héctor A González-Usigli
- Department of Neurology, High Specialty Medical Unit, Western National Medical Center of the Mexican Institute of Social Security, Guadalajara, Jalisco, Mexico
| | - Nayeli A Sánchez-Rosales
- Department of Neurology, High Specialty Medical Unit, Western National Medical Center of the Mexican Institute of Social Security, Guadalajara, Jalisco, Mexico
| | - Martha R Hernández-Preciado
- Department of Neurology, High Specialty Medical Unit, Western National Medical Center of the Mexican Institute of Social Security, Guadalajara, Jalisco, Mexico
| | | | - José J Hernández-Cruz
- Department of Philosophical and Methodological Disciplines and Service of Molecular Biology in medicine HC, University Health Sciences Center, University of Guadalajara, Guadalajara, Jalisco, Mexico
| | - Genaro Gabriel Ortiz
- Department of Neurology, High Specialty Medical Unit, Western National Medical Center of the Mexican Institute of Social Security, Guadalajara, Jalisco, Mexico
- Department of Philosophical and Methodological Disciplines and Service of Molecular Biology in medicine HC, University Health Sciences Center, University of Guadalajara, Guadalajara, Jalisco, Mexico
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Wicklein R, Kreitner L, Wild A, Aly L, Rueckert D, Hemmer B, Korn T, Menten MJ, Knier B. Retinal small vessel pathology is associated with disease burden in multiple sclerosis. Mult Scler 2024; 30:812-819. [PMID: 38751230 PMCID: PMC11134992 DOI: 10.1177/13524585241247775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/26/2024] [Accepted: 03/31/2024] [Indexed: 05/29/2024]
Abstract
BACKGROUND Alterations of the superficial retinal vasculature are commonly observed in multiple sclerosis (MS) and can be visualized through optical coherence tomography angiography (OCTA). OBJECTIVES This study aimed to examine changes in the retinal vasculature during MS and to integrate findings into current concepts of the underlying pathology. METHODS In this cross-sectional study, including 259 relapsing-remitting MS patients and 78 healthy controls, we analyzed OCTAs using deep-learning-based segmentation algorithm tools. RESULTS We identified a loss of small-sized vessels (diameter < 10 µm) in the superficial vascular complex in all MS eyes, irrespective of their optic neuritis (ON) history. This alteration was associated with MS disease burden and appears independent of retinal ganglion cell loss. In contrast, an observed reduction of medium-sized vessels (diameter 10-20 µm) was specific to eyes with a history of ON and was closely linked to ganglion cell atrophy. CONCLUSION These findings suggest distinct atrophy patterns in retinal vessels in patients with MS. Further studies are necessary to investigate retinal vessel alterations and their underlying pathology in MS.
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Affiliation(s)
- Rebecca Wicklein
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Linus Kreitner
- Institute for AI and Informatics in Medicine, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Anna Wild
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Lilian Aly
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Daniel Rueckert
- Institute for AI and Informatics in Medicine, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
- BioMedIA, Imperial College London, London, UK
| | - Bernhard Hemmer
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
- Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| | - Thomas Korn
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
- Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
- Institute for Experimental Neuroimmunology, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Martin J Menten
- Institute for AI and Informatics in Medicine, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
- BioMedIA, Imperial College London, London, UK
| | - Benjamin Knier
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
- Department of Neurology and Geriatric Neurology, Diakonie Klinikum Schwäbisch Hall, Schwäbisch Hall, Germany
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3
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Du X, Butler AG, Chen HY. Cell-cell interaction in the pathogenesis of inherited retinal diseases. Front Cell Dev Biol 2024; 12:1332944. [PMID: 38500685 PMCID: PMC10944940 DOI: 10.3389/fcell.2024.1332944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 02/06/2024] [Indexed: 03/20/2024] Open
Abstract
The retina is part of the central nervous system specialized for vision. Inherited retinal diseases (IRD) are a group of clinically and genetically heterogenous disorders that lead to progressive vision impairment or blindness. Although each disorder is rare, IRD accumulatively cause blindness in up to 5.5 million individuals worldwide. Currently, the pathophysiological mechanisms of IRD are not fully understood and there are limited treatment options available. Most IRD are caused by degeneration of light-sensitive photoreceptors. Genetic mutations that abrogate the structure and/or function of photoreceptors lead to visual impairment followed by blindness caused by loss of photoreceptors. In healthy retina, photoreceptors structurally and functionally interact with retinal pigment epithelium (RPE) and Müller glia (MG) to maintain retinal homeostasis. Multiple IRD with photoreceptor degeneration as a major phenotype are caused by mutations of RPE- and/or MG-associated genes. Recent studies also reveal compromised MG and RPE caused by mutations in ubiquitously expressed ciliary genes. Therefore, photoreceptor degeneration could be a direct consequence of gene mutations and/or could be secondary to the dysfunction of their interaction partners in the retina. This review summarizes the mechanisms of photoreceptor-RPE/MG interaction in supporting retinal functions and discusses how the disruption of these processes could lead to photoreceptor degeneration, with an aim to provide a unique perspective of IRD pathogenesis and treatment paradigm. We will first describe the biology of retina and IRD and then discuss the interaction between photoreceptors and MG/RPE as well as their implications in disease pathogenesis. Finally, we will summarize the recent advances in IRD therapeutics targeting MG and/or RPE.
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Affiliation(s)
| | | | - Holly Y. Chen
- Department of Cell, Developmental and Integrative Biology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
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4
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Afzali AM, Nirschl L, Sie C, Pfaller M, Ulianov O, Hassler T, Federle C, Petrozziello E, Kalluri SR, Chen HH, Tyystjärvi S, Muschaweckh A, Lammens K, Delbridge C, Büttner A, Steiger K, Seyhan G, Ottersen OP, Öllinger R, Rad R, Jarosch S, Straub A, Mühlbauer A, Grassmann S, Hemmer B, Böttcher JP, Wagner I, Kreutzfeldt M, Merkler D, Pardàs IB, Schmidt Supprian M, Buchholz VR, Heink S, Busch DH, Klein L, Korn T. B cells orchestrate tolerance to the neuromyelitis optica autoantigen AQP4. Nature 2024; 627:407-415. [PMID: 38383779 PMCID: PMC10937377 DOI: 10.1038/s41586-024-07079-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 01/16/2024] [Indexed: 02/23/2024]
Abstract
Neuromyelitis optica is a paradigmatic autoimmune disease of the central nervous system, in which the water-channel protein AQP4 is the target antigen1. The immunopathology in neuromyelitis optica is largely driven by autoantibodies to AQP42. However, the T cell response that is required for the generation of these anti-AQP4 antibodies is not well understood. Here we show that B cells endogenously express AQP4 in response to activation with anti-CD40 and IL-21 and are able to present their endogenous AQP4 to T cells with an AQP4-specific T cell receptor (TCR). A population of thymic B cells emulates a CD40-stimulated B cell transcriptome, including AQP4 (in mice and humans), and efficiently purges the thymic TCR repertoire of AQP4-reactive clones. Genetic ablation of Aqp4 in B cells rescues AQP4-specific TCRs despite sufficient expression of AQP4 in medullary thymic epithelial cells, and B-cell-conditional AQP4-deficient mice are fully competent to raise AQP4-specific antibodies in productive germinal-centre responses. Thus, the negative selection of AQP4-specific thymocytes is dependent on the expression and presentation of AQP4 by thymic B cells. As AQP4 is expressed in B cells in a CD40-dependent (but not AIRE-dependent) manner, we propose that thymic B cells might tolerize against a group of germinal-centre-associated antigens, including disease-relevant autoantigens such as AQP4.
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Affiliation(s)
- Ali Maisam Afzali
- Institute for Experimental Neuroimmunology, Technical University of Munich School of Medicine and Health, Munich, Germany
- Department of Neurology, Technical University of Munich School of Medicine and Health, Munich, Germany
- Munich Cluster for Systems Neurology, Munich, Germany
| | - Lucy Nirschl
- Institute for Experimental Neuroimmunology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Christopher Sie
- Institute for Experimental Neuroimmunology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Monika Pfaller
- Institute for Experimental Neuroimmunology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Oleksii Ulianov
- Institute for Experimental Neuroimmunology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Tobias Hassler
- Biomedical Center (BMC), Institute for Immunology, Faculty of Medicine, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
| | - Christine Federle
- Biomedical Center (BMC), Institute for Immunology, Faculty of Medicine, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
| | - Elisabetta Petrozziello
- Biomedical Center (BMC), Institute for Immunology, Faculty of Medicine, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
| | - Sudhakar Reddy Kalluri
- Department of Neurology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Hsin Hsiang Chen
- Institute for Experimental Neuroimmunology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Sofia Tyystjärvi
- Institute for Experimental Neuroimmunology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Andreas Muschaweckh
- Institute for Experimental Neuroimmunology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Katja Lammens
- Department of Biochemistry at the Gene Center, Ludwig-Maximilians-University, Munich, Germany
| | - Claire Delbridge
- Institute of Pathology, Technical University of Munich School of Medicine and Health, Munich, Germany
- Department of Neuropathology, Institute of Pathology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Andreas Büttner
- Institute of Forensic Medicine, Rostock University Medical Center, Rostock, Germany
| | - Katja Steiger
- Institute of Pathology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Gönül Seyhan
- Institute for Experimental Hematology, TranslaTUM Cancer Center, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Ole Petter Ottersen
- Division of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Rupert Öllinger
- Institute of Molecular Oncology and Functional Genomics, TranslaTUM Cancer Center, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Roland Rad
- Institute of Molecular Oncology and Functional Genomics, TranslaTUM Cancer Center, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Sebastian Jarosch
- Institute for Medical Microbiology, Immunology and Hygiene, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Adrian Straub
- Institute for Medical Microbiology, Immunology and Hygiene, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Anton Mühlbauer
- Institute for Medical Microbiology, Immunology and Hygiene, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Simon Grassmann
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Bernhard Hemmer
- Department of Neurology, Technical University of Munich School of Medicine and Health, Munich, Germany
- Munich Cluster for Systems Neurology, Munich, Germany
| | - Jan P Böttcher
- Institute of Molecular Immunology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Ingrid Wagner
- Department of Pathology and Immunology, Division of Clinical Pathology, Geneva Faculty of Medicine, Centre Médical Universitaire, Geneva, Switzerland
| | - Mario Kreutzfeldt
- Department of Pathology and Immunology, Division of Clinical Pathology, Geneva Faculty of Medicine, Centre Médical Universitaire, Geneva, Switzerland
| | - Doron Merkler
- Department of Pathology and Immunology, Division of Clinical Pathology, Geneva Faculty of Medicine, Centre Médical Universitaire, Geneva, Switzerland
| | | | - Marc Schmidt Supprian
- Institute for Experimental Hematology, TranslaTUM Cancer Center, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Veit R Buchholz
- Institute for Medical Microbiology, Immunology and Hygiene, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Sylvia Heink
- Institute for Experimental Neuroimmunology, Technical University of Munich School of Medicine and Health, Munich, Germany
| | - Dirk H Busch
- Institute for Medical Microbiology, Immunology and Hygiene, Technical University of Munich School of Medicine and Health, Munich, Germany
- German Center for Infection Research (DZIF), Partner Site Munich, Munich, Germany
| | - Ludger Klein
- Biomedical Center (BMC), Institute for Immunology, Faculty of Medicine, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
| | - Thomas Korn
- Institute for Experimental Neuroimmunology, Technical University of Munich School of Medicine and Health, Munich, Germany.
- Department of Neurology, Technical University of Munich School of Medicine and Health, Munich, Germany.
- Munich Cluster for Systems Neurology, Munich, Germany.
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5
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Romahn EF, Wiltgen T, Bussas M, Aly L, Wicklein R, Noll C, Berthele A, Dehmelt V, Mardin C, Zimmer C, Korn T, Hemmer B, Kirschke JS, Mühlau M, Knier B. Association of retinal vessel pathology and brain atrophy in relapsing-remitting multiple sclerosis. Front Immunol 2023; 14:1284986. [PMID: 38090586 PMCID: PMC10715309 DOI: 10.3389/fimmu.2023.1284986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 11/07/2023] [Indexed: 12/18/2023] Open
Abstract
Background Optical coherence tomography angiography (OCTA) allows non-invasive assessment of retinal vessel structures. Thinning and loss of retinal vessels is evident in eyes of patients with multiple sclerosis (MS) and might be associated with a proinflammatory disease phenotype and worse prognosis. We investigated whether changes of the retinal vasculature are linked to brain atrophy and disability in MS. Material and methods This study includes one longitudinal observational cohort (n=79) of patients with relapsing-remitting MS. Patients underwent annual assessment of the expanded disability status scale (EDSS), timed 25-foot walk, symbol digit modalities test (SDMT), retinal optical coherence tomography (OCT), OCTA, and brain MRI during a follow-up duration of at least 20 months. We investigated intra-individual associations between changes in the retinal architecture, vasculature, brain atrophy and disability. Eyes with a history of optic neuritis (ON) were excluded. Results We included 79 patients with a median disease duration of 12 (interquartile range 2 - 49) months and a median EDSS of 1.0 (0 - 2.0). Longitudinal retinal axonal and ganglion cell loss were linked to grey matter atrophy, cortical atrophy, and volume loss of the putamen. We observed an association between vessel loss of the superficial vascular complex (SVC) and both grey and white matter atrophy. Both observations were independent of retinal ganglion cell loss. Moreover, patients with worsening of the EDSS and SDMT revealed a pronounced longitudinal rarefication of the SVC and the deep vascular complex. Discussion ON-independent narrowing of the retinal vasculature might be linked to brain atrophy and disability in MS. Our findings suggest that retinal OCTA might be a new tool for monitoring neurodegeneration during MS.
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Affiliation(s)
- Eva Feodora Romahn
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Tun Wiltgen
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Matthias Bussas
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Lilian Aly
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Rebecca Wicklein
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Christina Noll
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Achim Berthele
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Vera Dehmelt
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Christian Mardin
- Department of Ophthalmology, University Hospital of Erlangen-Nuremberg, Erlangen, Germany
| | - Claus Zimmer
- Department of Neuroradiology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Thomas Korn
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
- Institute for Experimental Neuroimmunology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Bernhard Hemmer
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Jan S. Kirschke
- Department of Neuroradiology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Mark Mühlau
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Benjamin Knier
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany
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6
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Padovani-Claudio DA, Ramos CJ, Capozzi ME, Penn JS. Elucidating glial responses to products of diabetes-associated systemic dyshomeostasis. Prog Retin Eye Res 2023; 94:101151. [PMID: 37028118 PMCID: PMC10683564 DOI: 10.1016/j.preteyeres.2022.101151] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 04/08/2023]
Abstract
Diabetic retinopathy (DR) is a leading cause of blindness in working age adults. DR has non-proliferative stages, characterized in part by retinal neuroinflammation and ischemia, and proliferative stages, characterized by retinal angiogenesis. Several systemic factors, including poor glycemic control, hypertension, and hyperlipidemia, increase the risk of DR progression to vision-threatening stages. Identification of cellular or molecular targets in early DR events could allow more prompt interventions pre-empting DR progression to vision-threatening stages. Glia mediate homeostasis and repair. They contribute to immune surveillance and defense, cytokine and growth factor production and secretion, ion and neurotransmitter balance, neuroprotection, and, potentially, regeneration. Therefore, it is likely that glia orchestrate events throughout the development and progression of retinopathy. Understanding glial responses to products of diabetes-associated systemic dyshomeostasis may reveal novel insights into the pathophysiology of DR and guide the development of novel therapies for this potentially blinding condition. In this article, first, we review normal glial functions and their putative roles in the development of DR. We then describe glial transcriptome alterations in response to systemic circulating factors that are upregulated in patients with diabetes and diabetes-related comorbidities; namely glucose in hyperglycemia, angiotensin II in hypertension, and the free fatty acid palmitic acid in hyperlipidemia. Finally, we discuss potential benefits and challenges associated with studying glia as targets of DR therapeutic interventions. In vitro stimulation of glia with glucose, angiotensin II and palmitic acid suggests that: 1) astrocytes may be more responsive than other glia to these products of systemic dyshomeostasis; 2) the effects of hyperglycemia on glia are likely to be largely osmotic; 3) fatty acid accumulation may compound DR pathophysiology by promoting predominantly proinflammatory and proangiogenic transcriptional alterations of macro and microglia; and 4) cell-targeted therapies may offer safer and more effective avenues for DR treatment as they may circumvent the complication of pleiotropism in retinal cell responses. Although several molecules previously implicated in DR pathophysiology are validated in this review, some less explored molecules emerge as potential therapeutic targets. Whereas much is known regarding glial cell activation, future studies characterizing the role of glia in DR and how their activation is regulated and sustained (independently or as part of retinal cell networks) may help elucidate mechanisms of DR pathogenesis and identify novel drug targets for this blinding disease.
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Affiliation(s)
- Dolly Ann Padovani-Claudio
- Department of Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, B3321A Medical Center North, 1161 21st Avenue South, Nashville, TN, 37232-0011, USA.
| | - Carla J Ramos
- Department of Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, AA1324 Medical Center North, 1161 21st Avenue South, Nashville, TN, 37232-0011, USA.
| | - Megan E Capozzi
- Duke Molecular Physiology Institute, Duke University School of Medicine, 300 North Duke Street, Durham, NC, 27701, USA.
| | - John S Penn
- Department of Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, B3307 Medical Center North, 1161 21st Avenue South, Nashville, TN, 37232-0011, USA.
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7
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Gotoh M, Miyamoto Y, Ikeshima-Kataoka H. Astrocytic Neuroimmunological Roles Interacting with Microglial Cells in Neurodegenerative Diseases. Int J Mol Sci 2023; 24:ijms24021599. [PMID: 36675113 PMCID: PMC9865248 DOI: 10.3390/ijms24021599] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/06/2023] [Accepted: 01/10/2023] [Indexed: 01/15/2023] Open
Abstract
Both astrocytic and microglial functions have been extensively investigated in healthy subjects and neurodegenerative diseases. For astrocytes, not only various sub-types were identified but phagocytic activity was also clarified recently and is making dramatic progress. In this review paper, we mostly focus on the functional role of astrocytes in the extracellular matrix and on interactions between reactive astrocytes and reactive microglia in normal states and in neurodegenerative diseases, because the authors feel it is necessary to elucidate the mechanisms among activated glial cells in the pathology of neurological diseases in order to pave the way for drug discovery. Finally, we will review cyclic phosphatidic acid (cPA), a naturally occurring phospholipid mediator that induces a variety of biological activities in the brain both in vivo and in vitro. We propose that cPA may serve as a novel therapeutic molecule for the treatment of brain injury and neuroinflammation.
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Affiliation(s)
- Mari Gotoh
- Department of Clinical Laboratory Medicine, Faculty of Medical Technology, Teikyo University, 2-11-1, Itabashi-ku, Tokyo 173-8605, Japan
- Institute for Human Life Science, Ochanomizu University, 2-1-1 Ohtsuka, Bunkyo-ku, Tokyo 112-8610, Japan
| | - Yasunori Miyamoto
- Institute for Human Life Science, Ochanomizu University, 2-1-1 Ohtsuka, Bunkyo-ku, Tokyo 112-8610, Japan
| | - Hiroko Ikeshima-Kataoka
- Department of Biology, Keio University, 4-1-1, Hiyoshi, Kohoku-ku, Yokohama 223-8521, Japan
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
- Faculty of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan
- Correspondence:
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8
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Noll C, Hiltensperger M, Aly L, Wicklein R, Afzali AM, Mardin C, Gasperi C, Berthele A, Hemmer B, Korn T, Knier B. Association of the retinal vasculature, intrathecal immunity, and disability in multiple sclerosis. Front Immunol 2022; 13:997043. [PMID: 36439131 PMCID: PMC9695398 DOI: 10.3389/fimmu.2022.997043] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 10/20/2022] [Indexed: 10/15/2023] Open
Abstract
BACKGROUND Optical coherence tomography angiography (OCT-A) is a novel technique allowing non-invasive assessment of the retinal vasculature. During relapsing remitting multiple sclerosis (RRMS), retinal vessel loss occurs in eyes suffering from acute optic neuritis and recent data suggest that retinal vessel loss might also be evident in non-affected eyes. We investigated whether alterations of the retinal vasculature are linked to the intrathecal immunity and whether they allow prognostication of the future disease course. MATERIAL AND METHODS This study includes two different patient cohorts recruited at a tertiary German academic multiple sclerosis center between 2018 and 2020 and a cohort of 40 healthy controls. A total of 90 patients with RRMS undergoing lumbar puncture and OCT-A analysis were enrolled into a cross-sectional cohort study to search for associations between the retinal vasculature and the intrathecal immune compartment. We recruited another 86 RRMS patients into a prospective observational cohort study who underwent clinical examination, OCT-A and cerebral magnetic resonance imaging at baseline and during annual follow-up visits to clarify whether alterations of the retinal vessels are linked to RRMS disease activity. Eyes with a history of optic neuritis were excluded from the analysis. RESULTS Rarefication of the superficial vascular complex occured during RRMS and was linked to higher frequencies of activated B cells and higher levels of the pro-inflammatory cytokines interferon-γ, tumor necrosis factor α and interleukin-17 in the cerebrospinal fluid. During a median follow-up of 23 (interquartile range 14 - 25) months, vessel loss within the superficial (hazard ratio [HR] 1.6 for a 1%-point decrease in vessel density, p=0.01) and deep vascular complex (HR 1.6 for a 1%-point decrease, p=0.05) was associated with future disability worsening. DISCUSSION Optic neuritis independent rarefication of the retinal vasculature might be linked to neuroinflammatory processes during RRMS and might predict a worse disease course. Thus, OCT-A might be a novel biomarker to monitor disease activity and predict future disability.
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Affiliation(s)
- Christina Noll
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine, Technical University of Munich, Munich, Germany
| | - Michael Hiltensperger
- Institute for Experimental Neuroimmunology, TUM School of Medicine, Technical University of Munich, Munich, Germany
| | - Lilian Aly
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine, Technical University of Munich, Munich, Germany
| | - Rebecca Wicklein
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine, Technical University of Munich, Munich, Germany
| | - Ali Maisam Afzali
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine, Technical University of Munich, Munich, Germany
- Institute for Experimental Neuroimmunology, TUM School of Medicine, Technical University of Munich, Munich, Germany
- Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| | - Christian Mardin
- Department of Ophthalmology, University Hospital of Erlangen-Nuremberg, Erlangen, Germany
| | - Christiane Gasperi
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine, Technical University of Munich, Munich, Germany
| | - Achim Berthele
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine, Technical University of Munich, Munich, Germany
| | - Bernhard Hemmer
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine, Technical University of Munich, Munich, Germany
- Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| | - Thomas Korn
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine, Technical University of Munich, Munich, Germany
- Institute for Experimental Neuroimmunology, TUM School of Medicine, Technical University of Munich, Munich, Germany
- Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| | - Benjamin Knier
- Department of Neurology, Klinikum rechts der Isar, TUM School of Medicine, Technical University of Munich, Munich, Germany
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Neurovascular injury associated non-apoptotic endothelial caspase-9 and astroglial caspase-9 mediate inflammation and contrast sensitivity decline. Cell Death Dis 2022; 13:937. [PMID: 36347836 PMCID: PMC9643361 DOI: 10.1038/s41419-022-05387-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/25/2022] [Accepted: 10/27/2022] [Indexed: 11/11/2022]
Abstract
Retinal neurovascular injuries are a leading cause of vision loss in young adults presenting unmet therapeutic needs. Neurovascular injuries damage homeostatic communication between endothelial, pericyte, glial, and neuronal cells through signaling pathways that remain to be established. To understand the mechanisms that contribute to neuronal death, we use a mouse model of retinal vein occlusion (RVO). Using this model, we previously discovered that after vascular damage, there was non-apoptotic activation of endothelial caspase-9 (EC Casp9); knock-out of EC Casp9 led to a decrease in retinal edema, capillary ischemia, and neuronal death. In this study, we aimed to explore the role of EC Casp9 in vision loss and inflammation. We found that EC Casp9 is implicated in contrast sensitivity decline, induction of inflammatory cytokines, and glial reactivity. One of the noted glial changes was increased levels of astroglial cl-caspase-6, which we found to be activated cell intrinsically by astroglial caspase-9 (Astro Casp9). Lastly, we discovered that Astro Casp9 contributes to capillary ischemia and contrast sensitivity decline after RVO (P-RVO). These findings reveal specific endothelial and astroglial non-apoptotic caspase-9 roles in inflammation and neurovascular injury respectively; and concomitant relevancy to contrast sensitivity decline.
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