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Elwood BW, Godwin CR, Anders JJ, Kardon RH, Gramlich OW. Correlation of Visual System Biomarkers With Motor Deficits in Experimental Autoimmune Encephalomyelitis-Optic Neuritis. Transl Vis Sci Technol 2024; 13:1. [PMID: 39087931 DOI: 10.1167/tvst.13.8.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2024] Open
Abstract
Purpose Experimental autoimmune encephalomyelitis (EAE) scoring, the most commonly used primary outcome metric for an in vivo model of multiple sclerosis (MS), is highly variable and subjective. Here we explored the use of visual biomarkers in EAE as more objective and clinically relevant primary outcomes. Methods Motor impairment in myelin oligodendrocyte glycoprotein-immunized C57BL/6J mice was quantified using a five-point EAE grading scale. Pattern electroretinography (pERG) and retinal ganglion cell/inner plexiform layer (RGC/IPL) complex thickness were measured 60 days after induction. Optic nerve histopathology was analyzed at endpoint. Results EAE mice displayed motor impairments ranging from mild to severe. Significant correlations were seen between pERG amplitude and last EAE score, mean EAE score, and cumulative EAE score. Optical coherence tomography (OCT) analysis demonstrated a significant correlation between thinning of the RGC/IPL complex and both EAE score and pERG amplitude. Optic nerve histopathology showed significant correlations between demyelination and cumulative EAE score, pERG amplitude, and RGC/IPL complex thickness, as well as between immune cell infiltration and cumulative EAE score, pERG amplitude, and RGC/IPL complex thickness in EAE mice. Conclusions Unlike EAE scoring, pERG and OCT show direct measurement of retinal structure and function. Therefore we conclude that visual outcomes are well suited as a direct assessment of optic nerve involvement in this EAE model of MS while also being indicative of motor impairment. Translational Relevance Standardizing directly translatable measurements as primary outcome parameters in the murine EAE model could lead to more rapid and relevant testing of new therapeutic approaches for mitigating MS.
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Affiliation(s)
- Benjamin W Elwood
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
- Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs Health Care System, Iowa City, IA, USA
| | - Cheyanne R Godwin
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
- Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs Health Care System, Iowa City, IA, USA
| | - Jeffrey J Anders
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
- Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs Health Care System, Iowa City, IA, USA
- Department of Neuroscience and Pharmacology, University of Iowa, Iowa City, IA, USA
| | - Randy H Kardon
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
- Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs Health Care System, Iowa City, IA, USA
| | - Oliver W Gramlich
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
- Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs Health Care System, Iowa City, IA, USA
- Department of Neuroscience and Pharmacology, University of Iowa, Iowa City, IA, USA
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Bonneau N, Potey A, Blond F, Guerin C, Baudouin C, Peyrin JM, Brignole-Baudouin F, Réaux-Le Goazigo A. Assessment of corneal nerve regeneration after axotomy in a compartmentalized microfluidic chip model with automated 3D high resolution live-imaging. Front Cell Neurosci 2024; 18:1417653. [PMID: 39076204 PMCID: PMC11285198 DOI: 10.3389/fncel.2024.1417653] [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: 04/15/2024] [Accepted: 06/26/2024] [Indexed: 07/31/2024] Open
Abstract
Introduction Damage to the corneal nerves can result in discomfort and chronic pain, profoundly impacting the quality of life of patients. Development of novel in vitro method is crucial to better understand corneal nerve regeneration and to find new treatments for the patients. Existing in vitro models often overlook the physiology of primary sensory neurons, for which the soma is separated from the nerve endings. Methods To overcome this limitation, our novel model combines a compartmentalized microfluidic culture of trigeminal ganglion neurons from adult mice with live-imaging and automated 3D image analysis offering robust way to assess axonal regrowth after axotomy. Results Physical axotomy performed by a two-second aspiration led to a reproducible 70% axonal loss and altered the phenotype of the neurons, increasing the number of substance P-positive neurons 72 h post-axotomy. To validate our new model, we investigated axonal regeneration after exposure to pharmacological compounds. We selected various targets known to enhance or inhibit axonal regrowth and analyzed their basal expression in trigeminal ganglion cells by scRNAseq. NGF/GDNF, insulin, and Dooku-1 (Piezo1 antagonist) enhanced regrowth by 81, 74 and 157%, respectively, while Yoda-1 (Piezo1 agonist) had no effect. Furthermore, SARM1-IN-2 (Sarm1 inhibitor) inhibited axonal regrowth, leading to only 6% regrowth after 72 h of exposure (versus 34% regrowth without any compound). Discussion Combining compartmentalized trigeminal neuronal culture with advanced imaging and analysis allowed a thorough evaluation of the extent of the axotomy and subsequent axonal regrowth. This innovative approach holds great promise for advancing our understanding of corneal nerve injuries and regeneration and ultimately improving the quality of life for patients suffering from sensory abnormalities, and related conditions.
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Affiliation(s)
- Noémie Bonneau
- Sorbonne Université, INSERM, CNRS, IHU FOReSIGHT, Institut de la Vision, Paris, France
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, INSERM-DGOS CIC 1423, IHU FOReSIGHT, Paris, France
| | - Anaïs Potey
- Sorbonne Université, INSERM, CNRS, IHU FOReSIGHT, Institut de la Vision, Paris, France
| | - Frédéric Blond
- Sorbonne Université, INSERM, CNRS, IHU FOReSIGHT, Institut de la Vision, Paris, France
| | - Camille Guerin
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, INSERM-DGOS CIC 1423, IHU FOReSIGHT, Paris, France
| | - Christophe Baudouin
- Sorbonne Université, INSERM, CNRS, IHU FOReSIGHT, Institut de la Vision, Paris, France
- Inserm-DGOS CIC 1423, IHU Foresight, Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, Paris, France
- Hôpital Ambroise Paré, APHP, Université Versailles-Saint-Quentin-en-Yvelines, Boulogne-Billancourt, France
| | - Jean-Michel Peyrin
- UMR8246, Inserm U1130, IBPS, UPMC, Neurosciences Paris Seine, Sorbonne Université, Paris, France
| | - Françoise Brignole-Baudouin
- Sorbonne Université, INSERM, CNRS, IHU FOReSIGHT, Institut de la Vision, Paris, France
- Inserm-DGOS CIC 1423, IHU Foresight, Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, Paris, France
- Faculté de Pharmacie de Paris, Université Paris Cité, Paris, France
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Loreto A, Merlini E, Coleman MP. Programmed axon death: a promising target for treating retinal and optic nerve disorders. Eye (Lond) 2024; 38:1802-1809. [PMID: 38538779 PMCID: PMC11226669 DOI: 10.1038/s41433-024-03025-0] [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: 09/04/2023] [Revised: 02/13/2024] [Accepted: 03/08/2024] [Indexed: 07/07/2024] Open
Abstract
Programmed axon death is a druggable pathway of axon degeneration that has garnered considerable interest from pharmaceutical companies as a promising therapeutic target for various neurodegenerative disorders. In this review, we highlight mechanisms through which this pathway is activated in the retina and optic nerve, and discuss its potential significance for developing therapies for eye disorders and beyond. At the core of programmed axon death are two enzymes, NMNAT2 and SARM1, with pivotal roles in NAD metabolism. Extensive preclinical data in disease models consistently demonstrate remarkable, and in some instances, complete and enduring neuroprotection when this mechanism is targeted. Findings from animal studies are now being substantiated by genetic human data, propelling the field rapidly toward clinical translation. As we approach the clinical phase, the selection of suitable disorders for initial clinical trials targeting programmed axon death becomes crucial for their success. We delve into the multifaceted roles of programmed axon death and NAD metabolism in retinal and optic nerve disorders. We discuss the role of SARM1 beyond axon degeneration, including its potential involvement in neuronal soma death and photoreceptor degeneration. We also discuss genetic human data and environmental triggers of programmed axon death. Lastly, we touch upon potential therapeutic approaches targeting NMNATs and SARM1, as well as the nicotinamide trials for glaucoma. The extensive literature linking programmed axon death to eye disorders, along with the eye's suitability for drug delivery and visual assessments, makes retinal and optic nerve disorders strong contenders for early clinical trials targeting programmed axon death.
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Affiliation(s)
- Andrea Loreto
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, Cambridge, UK.
- School of Medical Sciences and Save Sight Institute, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.
| | - Elisa Merlini
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, Cambridge, UK
| | - Michael P Coleman
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, Cambridge, UK.
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Harris A, Verticchio Vercellin A, Weinreb RN, Khawaja A, MacGregor S, Pasquale LR. Lessons From The Glaucoma Foundation Think Tank 2023: A Patient-Centric Approach to Glaucoma. J Glaucoma 2024; 33:e1-e14. [PMID: 38129952 DOI: 10.1097/ijg.0000000000002353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023]
Abstract
PRCIS The main takeaways also included that BIG DATA repositories and AI are important combinatory tools to foster novel strategies to prevent and stabilize glaucoma and, in the future, recover vision loss from the disease. PURPOSE To summarize the main topics discussed during the 28th Annual Glaucoma Foundation Think Tank Meeting "A Patient-Centric Approach to Glaucoma" held in New York on June 9 and 10, 2023. METHODS The highlights of the sessions on BIG DATA, genetics, modifiable lifestyle risk factors, female sex hormones, and neuroprotection in the field of primary open angle glaucoma (POAG) were summarized. RESULTS The researchers discussed the importance of BIG DATA repositories available at national and international levels for POAG research, including the United Kingdom Biobank. Combining genotyped large cohorts worldwide, facilitated by artificial intelligence (AI) and machine-learning approaches, led to the milestone discovery of 312 genome-wide significant disease loci for POAG. While these loci could be combined into a polygenic risk score with clinical utility, Think Tank meeting participants also provided analytical epidemiological evidence that behavioral risk factors modify POAG polygenetic risk, citing specific examples related to caffeine and alcohol use. The impact of female sex hormones on POAG pathophysiology was discussed, as was neuroprotection and the potential use of AI to help mitigate specific challenges faced in clinical trials and speed approval of neuroprotective agents. CONCLUSIONS The experts agreed on the importance of genetics in defining individual POAG risk and highlighted the additional crucial role of lifestyle, gender, blood pressure, and vascular risk factors. The main takeaways also included that BIG DATA repositories and AI are important combinatory tools to foster novel strategies to prevent and stabilize glaucoma and, in the future, recover vision loss from the disease.
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Affiliation(s)
- Alon Harris
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai Hospital, New York, NY
| | | | - Robert N Weinreb
- Viterbi Family Department of Ophthalmology, Hamilton Glaucoma Center, Shiley Eye Institute, UC San Diego, La Jolla, CA
| | - Anthony Khawaja
- NIHR Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
| | - Stuart MacGregor
- Statistical Genetics Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Louis R Pasquale
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai Hospital, New York, NY
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5
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Zeng H, Mayberry JE, Wadkins D, Chen N, Summers DW, Kuehn MH. Loss of Sarm1 reduces retinal ganglion cell loss in chronic glaucoma. Acta Neuropathol Commun 2024; 12:23. [PMID: 38331947 PMCID: PMC10854189 DOI: 10.1186/s40478-024-01736-9] [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: 11/20/2023] [Accepted: 01/23/2024] [Indexed: 02/10/2024] Open
Abstract
Glaucoma is one of the leading causes of irreversible blindness worldwide and vision loss in the disease results from the deterioration of retinal ganglion cells (RGC) and their axons. Metabolic dysfunction of RGC plays a significant role in the onset and progression of the disease in both human patients and rodent models, highlighting the need to better define the mechanisms regulating cellular energy metabolism in glaucoma. This study sought to determine if Sarm1, a gene involved in axonal degeneration and NAD+ metabolism, contributes to glaucomatous RGC loss in a mouse model with chronic elevated intraocular pressure (IOP). Our data demonstrate that after 16 weeks of elevated IOP, Sarm1 knockout (KO) mice retain significantly more RGC than control animals. Sarm1 KO mice also performed significantly better when compared to control mice during optomotor testing, indicating that visual function is preserved in this group. Our findings also indicate that Sarm1 KO mice display mild ocular developmental abnormalities, including reduced optic nerve axon diameter and lower visual acuity than controls. Finally, we present data to indicate that SARM1 expression in the optic nerve is most prominently associated with oligodendrocytes. Taken together, these data suggest that attenuating Sarm1 activity through gene therapy, pharmacologic inhibition, or NAD+ supplementation, may be a novel therapeutic approach for patients with glaucoma.
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Affiliation(s)
- Huilan Zeng
- Department of Ophthalmology, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, People's Republic of China
| | - Jordan E Mayberry
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, IA, 52242, USA
- Iowa City VA Center for the Prevention and Treatment of Visual Loss, Iowa City, IA, 52246, USA
| | - David Wadkins
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, IA, 52242, USA
- Iowa City VA Center for the Prevention and Treatment of Visual Loss, Iowa City, IA, 52246, USA
| | - Nathan Chen
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, IA, 52242, USA
- Iowa City VA Center for the Prevention and Treatment of Visual Loss, Iowa City, IA, 52246, USA
| | - Daniel W Summers
- Department of Biology, The University of Iowa, Iowa City, IA, 52242, USA
| | - Markus H Kuehn
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, IA, 52242, USA.
- Iowa City VA Center for the Prevention and Treatment of Visual Loss, Iowa City, IA, 52246, USA.
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Guo Y, Mehrabian Z, Milbrandt J, DiAntonio A, Bernstein SL. Synergistic Protection of Retinal Ganglion Cells (RGCs) by SARM1 Inactivation with CNTF in a Rodent Model of Nonarteritic Anterior Ischemic Optic Neuropathy. Cells 2024; 13:202. [PMID: 38334594 PMCID: PMC10854792 DOI: 10.3390/cells13030202] [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: 11/03/2023] [Revised: 01/16/2024] [Accepted: 01/18/2024] [Indexed: 02/10/2024] Open
Abstract
We evaluated whether inhibiting sterile alpha and (Toll/interleukin receptor (TIR)) motif-containing 1 (SARM1) activity protects retinal ganglion cells (RGCs) following ischemic axonopathy (rodent nonarteritic anterior ischemic optic neuropathy: rNAION) by itself and combined with ciliary neurotrophic factor (CNTF). Genetically modified SARM1(-) rats were rNAION-induced in one eye and compared against equivalently induced wild-type animals of the same background. Optic nerve (ON) diameters were quantified using optical coherence tomography (SD-OCT). RGCs were quantified 30 d post-induction using retinal stereology for Brn3a(+) nuclei. ON sections were analyzed by TEM and immunohistochemistry. SARM1(-)(-) and WT animals were then bilaterally sequentially rNAION-induced. One eye received intravitreal vehicle injection following induction; the contralateral side received CNTF and was analyzed 30 d post-induction. Inhibiting SARM1 activity suppressed axonal collapse following ischemic axonopathy. SARM1(-) animals significantly reduced RGC loss, compared with WT animals (49.4 ± 6.8% RGC loss in SARM1(-) vs. 63.6 ± 3.2% sem RGC loss in WT; Mann-Whitney one-tailed U-test, (p = 0.049)). IVT-CNTF treatment vs. IVT-vehicle in SARM1(-) animals further reduced RGC loss by 24% at 30 d post-induction, but CNTF did not, by itself, improve long-term RGC survival in WT animals compared with vehicle (Mann-Whitney one-tailed t-test; p = 0.033). While inhibiting SARM1 activity is itself neuroprotective, combining SARM1 inhibition and CNTF treatment generated a long-term, synergistic neuroprotective effect in ischemic neuropathy. Combinatorial treatments for NAION utilizing independent neuroprotective mechanisms may thus provide a greater effect than individual treatment modalities.
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Affiliation(s)
- Yan Guo
- Departments of Ophthalmology and Visual Sciences, School of Medicine, University of Maryland, Baltimore, MD 21201, USA; (Y.G.); (Z.M.)
| | - Zara Mehrabian
- Departments of Ophthalmology and Visual Sciences, School of Medicine, University of Maryland, Baltimore, MD 21201, USA; (Y.G.); (Z.M.)
| | - Jeffrey Milbrandt
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, USA;
- Needleman Center for Neurometabolism and Axonal Therapeutics, St. Louis, MO 63110, USA;
| | - Aaron DiAntonio
- Needleman Center for Neurometabolism and Axonal Therapeutics, St. Louis, MO 63110, USA;
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Steven L. Bernstein
- Departments of Ophthalmology and Visual Sciences, School of Medicine, University of Maryland, Baltimore, MD 21201, USA; (Y.G.); (Z.M.)
- Anatomy and Neurobiology, School of Medicine, University of Maryland, Baltimore, MD 21201, USA
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7
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Del Negro I, Pauletto G, Verriello L, Spadea L, Salati C, Ius T, Zeppieri M. Uncovering the Genetics and Physiology behind Optic Neuritis. Genes (Basel) 2023; 14:2192. [PMID: 38137014 PMCID: PMC10742654 DOI: 10.3390/genes14122192] [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: 11/07/2023] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 12/24/2023] Open
Abstract
Optic neuritis (ON) is an inflammatory condition affecting the optic nerve, leading to vision impairment and potential vision loss. This manuscript aims to provide a comprehensive review of the current understanding of ON, including its definition, epidemiology, physiology, genetics, molecular pathways, therapy, ongoing clinical studies, and future perspectives. ON is characterized by inflammation of the optic nerve, often resulting from an autoimmune response. Epidemiological studies have shown a higher incidence in females and an association with certain genetic factors. The physiology of ON involves an immune-mediated attack on the myelin sheath surrounding the optic nerve, leading to demyelination and subsequent impairment of nerve signal transmission. This inflammatory process involves various molecular pathways, including the activation of immune cells and the release of pro-inflammatory cytokines. Genetic factors play a significant role in the susceptibility to ON. Several genes involved in immune regulation and myelin maintenance have been implicated in the disease pathogenesis. Understanding the genetic basis can provide insights into disease mechanisms and potential therapeutic targets. Therapy for ON focuses on reducing inflammation and promoting nerve regeneration. Future perspectives involve personalized medicine approaches based on genetic profiling, regenerative therapies to repair damaged myelin, and the development of neuroprotective strategies. Advancements in understanding molecular pathways, genetics, and diagnostic tools offer new opportunities for targeted therapies and improved patient outcomes in the future.
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Affiliation(s)
- Ilaria Del Negro
- Clinical Neurology Unit, Head-Neck and Neurosciences Department, Santa Maria della Misericordia University Hospital, 33100 Udine, Italy;
| | - Giada Pauletto
- Neurology Unit, Head-Neck and Neurosciences Department, Santa Maria della Misericordia University Hospital, 33100 Udine, Italy; (G.P.)
| | - Lorenzo Verriello
- Neurology Unit, Head-Neck and Neurosciences Department, Santa Maria della Misericordia University Hospital, 33100 Udine, Italy; (G.P.)
| | - Leopoldo Spadea
- Eye Clinic, Policlinico Umberto I, “Sapienza” University of Rome, 00142 Rome, Italy
| | - Carlo Salati
- Department of Ophthalmology, Head-Neck and Neurosciences Department, Santa Maria della Misericordia University Hospital, 33100 Udine, Italy
| | - Tamara Ius
- Neurosurgery Unit, Head-Neck and Neurosciences Department, Santa Maria della Misericordia University Hospital of Udine, 33100 Udine, Italy
| | - Marco Zeppieri
- Department of Ophthalmology, Head-Neck and Neurosciences Department, Santa Maria della Misericordia University Hospital, 33100 Udine, Italy
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8
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Chiarugi A. Glaucoma: neuroprotection with NAD-based therapeutic interventions. Trends Pharmacol Sci 2023; 44:869-879. [PMID: 37880000 DOI: 10.1016/j.tips.2023.09.010] [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: 09/06/2023] [Revised: 09/22/2023] [Accepted: 09/26/2023] [Indexed: 10/27/2023]
Abstract
Clinical evidence shows that intraocular hypertension is not the primary pathogenetic event of glaucoma, whereas early neurodegeneration of retinal ganglion cells (RGCs) represents a key therapeutic target. Unfortunately, failure of clinical trials with neuroprotective agents, in particular those testing the anti-excitotoxic drug memantine, generated widespread skepticism regarding the possibility of counteracting neurodegeneration during glaucoma. New avenues for neuroprotective approaches to counteract glaucoma evolution have been opened by the identification of a programmed axonal degeneration (PAD) program triggered by increased nicotinamide mononucleotide (NMN)/NAD concentration ratio. Positive results of proof-of-concept clinical studies based on sustaining axonal NAD homeostasis facilitated the design of Phase 2/3 trials. Here, I share my opinion on how neurodegeneration in glaucoma should be put into context, together with an appraisal of the pharmacological rationale of NAD-supporting therapies for use during glaucoma progression.
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Affiliation(s)
- Alberto Chiarugi
- Section of Clinical Pharmacology and Oncology, Department of Health Sciences, University of Florence, Florence, Italy; Headache Center and Clinical Pharmacology Unit, Careggi University Hospital, Florence, Italy.
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Wang W, Wang H. Understanding the complex genetics and molecular mechanisms underlying glaucoma. Mol Aspects Med 2023; 94:101220. [PMID: 37856931 DOI: 10.1016/j.mam.2023.101220] [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: 06/29/2023] [Revised: 10/09/2023] [Accepted: 10/12/2023] [Indexed: 10/21/2023]
Abstract
Glaucoma is the leading cause of irreversible blindness worldwide. Currently the only effective treatment for glaucoma is to reduce the intraocular pressure, which can halt the progression of the disease. Highlighting the importance of identifying individuals at risk of developing glaucoma and those with early-stage glaucoma will help patients receive treatment before sight loss. However, some cases of glaucoma do not have raised intraocular pressure. In fact, glaucoma is caused by a variety of different mechanisms and has a wide range of different subtypes. Understanding other risk factors, the underlying mechanisms, and the pathology of glaucoma might lead to novel treatments and treatment of underlying diseases. In this review we present the latest research into glaucoma including the genetics and molecular basis of the disease.
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Affiliation(s)
- Weiwei Wang
- Shaanxi Eye Hospital, Xi'an People's Hospital (Xi'an Fourth Hospital), Affiliated People's Hospital, Northwest University, Xi'an, 710004, Shaanxi Province, China.
| | - Huaizhou Wang
- Department of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China
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Fang F, Liu P, Huang H, Feng X, Li L, Sun Y, Kaufman RJ, Hu Y. RGC-specific ATF4 and/or CHOP deletion rescues glaucomatous neurodegeneration and visual function. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 33:286-295. [PMID: 37547290 PMCID: PMC10400881 DOI: 10.1016/j.omtn.2023.07.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 07/11/2023] [Indexed: 08/08/2023]
Abstract
Endoplasmic reticulum (ER) stress has been linked with various acute and chronic neurodegenerative diseases. We previously found that optic nerve (ON) injury and diseases induce neuronal ER stress in retinal ganglion cells (RGCs). We further demonstrated that germline deletion of CHOP preserves the structure and function of both RGC somata and axons in mouse glaucoma models. Here we report that RGC-specific deletion of CHOP and/or its upstream regulator ATF4 synergistically promotes RGC and ON survival and preserves visual function in mouse ON crush and silicone oil-induced ocular hypertension (SOHU) glaucoma models. Consistently, topical application of the ATF4/CHOP chemical inhibitor ISRIB or RGC-specific CRISPR-mediated knockdown of the ATF4 downstream effector Gadd45a also delivers significant neuroprotection in the SOHU glaucoma model. These studies suggest that blocking the neuronal intrinsic ATF4/CHOP axis of ER stress is a promising neuroprotection strategy for neurodegeneration.
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Affiliation(s)
- Fang Fang
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha 410011, China
| | - Pingting Liu
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Haoliang Huang
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Xue Feng
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Liang Li
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Yang Sun
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Randal J. Kaufman
- Degenerative Diseases Program, Center for Genetic Disorders and Aging Research, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Yang Hu
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
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