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Bou Ghanem GO, Wareham LK, Calkins DJ. Addressing neurodegeneration in glaucoma: Mechanisms, challenges, and treatments. Prog Retin Eye Res 2024; 100:101261. [PMID: 38527623 DOI: 10.1016/j.preteyeres.2024.101261] [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: 12/28/2023] [Revised: 03/15/2024] [Accepted: 03/19/2024] [Indexed: 03/27/2024]
Abstract
Glaucoma is the leading cause of irreversible blindness globally. The disease causes vision loss due to neurodegeneration of the retinal ganglion cell (RGC) projection to the brain through the optic nerve. Glaucoma is associated with sensitivity to intraocular pressure (IOP). Thus, mainstay treatments seek to manage IOP, though many patients continue to lose vision. To address neurodegeneration directly, numerous preclinical studies seek to develop protective or reparative therapies that act independently of IOP. These include growth factors, compounds targeting metabolism, anti-inflammatory and antioxidant agents, and neuromodulators. Despite success in experimental models, many of these approaches fail to translate into clinical benefits. Several factors contribute to this challenge. Firstly, the anatomic structure of the optic nerve head differs between rodents, nonhuman primates, and humans. Additionally, animal models do not replicate the complex glaucoma pathophysiology in humans. Therefore, to enhance the success of translating these findings, we propose two approaches. First, thorough evaluation of experimental targets in multiple animal models, including nonhuman primates, should precede clinical trials. Second, we advocate for combination therapy, which involves using multiple agents simultaneously, especially in the early and potentially reversible stages of the disease. These strategies aim to increase the chances of successful neuroprotective treatment for glaucoma.
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Affiliation(s)
- Ghazi O Bou Ghanem
- Vanderbilt Eye Institute, Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.
| | - Lauren K Wareham
- Vanderbilt Eye Institute, Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.
| | - David J Calkins
- Vanderbilt Eye Institute, Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.
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Holden JM, Wareham LK, Calkins DJ. Retinal astrocyte morphology predicts integration of vascular and neuronal architecture. Front Neurosci 2023; 17:1244679. [PMID: 37621717 PMCID: PMC10445659 DOI: 10.3389/fnins.2023.1244679] [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: 06/22/2023] [Accepted: 07/24/2023] [Indexed: 08/26/2023] Open
Abstract
Astrocytes are important regulators of blood flow and play a key role in the response to injury and disease in the central nervous system (CNS). Despite having an understanding that structural changes to these cells have consequences for local neurovascular physiology, individual astrocyte morphology remains largely unexplored in the retina. Here, we used MORF3 mice to capture full membranous morphology for over fifteen hundred individual astrocytes in the mouse retina, a highly metabolically active component of the CNS. We demonstrate that retinal astrocytes have been misrepresented as stellate in morphology due to marker use like GFAP and S100β which underestimates cell complexity. We also find that astrocytes contain recurring morphological motifs which are predictive of the underlying neurovascular architecture of the inner retina and suggestive of function. These motifs predict fine sampling and integration of retinal ganglion cell electrical activity with consequences for blood flow regulation. Additionally, our data shows that astrocytes participate in neurovascular interactions to a much greater degree than currently reported. 100% of cells contact the vasculature through one of three mutually exclusive classes of connections. Similarly, 100% of cells contact some neuronal element, be it an RGC axon or soma. Finally, we report that astrocyte morphology depends on retinal eccentricity, with cells appearing compressed near the nerve head and in the periphery. These results reveal a large degree of astrocyte morphological complexity that informs their contribution to neurovascular coupling in the retina.
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Affiliation(s)
- Joseph M. Holden
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Neuroscience Graduate Program, Vanderbilt University, Nashville, TN, United States
| | - Lauren K. Wareham
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, TN, United States
| | - David J. Calkins
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, TN, United States
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3
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Ail D, Nava D, Hwang IP, Brazhnikova E, Nouvel-Jaillard C, Dentel A, Joffrois C, Rousseau L, Dégardin J, Bertin S, Sahel JA, Goureau O, Picaud S, Dalkara D. Inducible nonhuman primate models of retinal degeneration for testing end-stage therapies. SCIENCE ADVANCES 2023; 9:eadg8163. [PMID: 37531424 PMCID: PMC10396314 DOI: 10.1126/sciadv.adg8163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 06/29/2023] [Indexed: 08/04/2023]
Abstract
The anatomical differences between the retinas of humans and most animal models pose a challenge for testing novel therapies. Nonhuman primate (NHP) retina is anatomically closest to the human retina. However, there is a lack of relevant NHP models of retinal degeneration (RD) suitable for preclinical studies. To address this unmet need, we generated three distinct inducible cynomolgus macaque models of RD. We developed two genetically targeted strategies using optogenetics and CRISPR-Cas9 to ablate rods and mimic rod-cone dystrophy. In addition, we created an acute model by physical separation of the photoreceptors and retinal pigment epithelium using a polymer patch. Among the three models, the CRISPR-Cas9-based approach was the most advantageous model in view of recapitulating disease-specific features and its ease of implementation. The acute model, however, resulted in the fastest degeneration, making it the most relevant model for testing end-stage vision restoration therapies such as stem cell transplantation.
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Affiliation(s)
- Divya Ail
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
| | - Diane Nava
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
| | - In Pyo Hwang
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
| | - Elena Brazhnikova
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
| | | | - Alexandre Dentel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
- CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, F-75012 Paris, France
- Department of Ophthalmology, Pitié-Salpêtrière University Hospital, F-75013 Paris, France
| | - Corentin Joffrois
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
| | - Lionel Rousseau
- ESYCOM, Université Eiffel, CNRS, CNAM, ESIEE Paris, F-77454 Marne-la-Vallée, France
| | - Julie Dégardin
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
| | - Stephane Bertin
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
- CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, F-75012 Paris, France
| | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
- CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, F-75012 Paris, France
- Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- Fondation Ophtalmologique Adolphe de Rothschild, F-75019 Paris, France
| | - Olivier Goureau
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
| | - Serge Picaud
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
| | - Deniz Dalkara
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
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4
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Chan ASY, Tun SBB, Lynn MN, Ho C, Tun TA, Girard MJA, Sultana R, Barathi VA, Aung T, Aihara M. Intravitreal Neuroglobin Mitigates Primate Experimental Glaucomatous Structural Damage in Association with Reduced Optic Nerve Microglial and Complement 3-Astrocyte Activation. Biomolecules 2023; 13:961. [PMID: 37371541 DOI: 10.3390/biom13060961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 05/18/2023] [Accepted: 05/25/2023] [Indexed: 06/29/2023] Open
Abstract
Current management of glaucomatous optic neuropathy is limited to intraocular pressure control. Neuroglobin (Ngb) is an endogenous neuroprotectant expressed in neurons and astrocytes. We recently showed that exogenous intravitreal Ngb reduced inflammatory cytokines and microglial activation in a rodent model of hypoxia. We thus hypothesised that IVT-Ngb may also be neuroprotective in experimental glaucoma (EG) by mitigating optic nerve (ON) astrogliosis and microgliosis as well as structural damage. In this study using a microbead-induced model of EG in six Cynomolgus primates, optical coherence imaging showed that Ngb-treated EG eyes had significantly less thinning of the peripapillary minimum rim width, retinal nerve fibre layer thickness, and ON head cupping than untreated EG eyes. Immunohistochemistry confirmed that ON astrocytes overexpressed Ngb following Ngb treatment. A reduction in complement 3 and cleaved-caspase 3 activated microglia and astrocytes was also noted. Our findings in higher-order primates recapitulate the effects of neuroprotection by Ngb treatment in rodent EG studies and suggest that Ngb may be a potential candidate for glaucoma neuroprotection in humans.
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Affiliation(s)
- Anita S Y Chan
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Singapore National Eye Centre, Singapore 168751, Singapore
- Duke-NUS Medical School, Singapore 169857, Singapore
| | - Sai B B Tun
- Singapore Eye Research Institute, Singapore 169856, Singapore
| | - Myoe N Lynn
- Singapore Eye Research Institute, Singapore 169856, Singapore
| | - Candice Ho
- Singapore Eye Research Institute, Singapore 169856, Singapore
| | - Tin A Tun
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Duke-NUS Medical School, Singapore 169857, Singapore
| | - Michaël J A Girard
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Ophthalmic Engineering & Innovation Laboratory (OEIL), Singapore Eye Research Institute, Singapore 169856, Singapore
| | | | - Veluchamy A Barathi
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Duke-NUS Medical School, Singapore 169857, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore
| | - Tin Aung
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Singapore National Eye Centre, Singapore 168751, Singapore
- Duke-NUS Medical School, Singapore 169857, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore
| | - Makoto Aihara
- Department of Ophthalmology, University of Tokyo, Tokyo 113-8654, Japan
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Sun Y, Wirta D, Murahashi W, Mathur V, Sankaranarayanan S, Taylor LK, Yednock T, Fong DS, Goldberg JL. Safety and Target Engagement of C1q Inhibitor ANX007 in Neurodegenerative Eye Disease: Results from Phase 1 Studies in Glaucoma. OPHTHALMOLOGY SCIENCE 2023; 3:100290. [PMID: 37124168 PMCID: PMC10130689 DOI: 10.1016/j.xops.2023.100290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 02/26/2023]
Abstract
Purpose Complement C1q, the initiating molecule of the classical complement cascade, is involved in synapse elimination and neuronal loss in neurodegenerative diseases including glaucoma. Here we report an evaluation of the safety, tolerability, and ocular pharmacokinetics (PK) and pharmacodynamics of intravitreal (IVT) injections of ANX007, an anti-C1q monoclonal antibody fragment that blocks activation of the classical complement cascade. Design An open-label, single-dose-escalation phase Ia study followed by a double-masked, randomized, sham-controlled, repeat-injection phase Ib study. Participants A total of 26 patients with primary open-angle glaucoma. Methods Nine patients with primary open-angle glaucoma (mean Humphrey visual field deviation between -3 and -18 decibels [dB]) were enrolled in phase Ia and received single doses of ANX007 (1.0 mg, n = 3; 2.5 mg, n = 3; or 5.0 mg, n = 3). Seventeen patients (mean Humphrey visual field deviation between -3 and -24 dB) were enrolled in phase Ib and randomized to 2 monthly doses of ANX007 (sham, n = 6; 2.5 mg ANX007, n = 6; or 5 mg ANX007, n = 5). Main Outcome Measures Safety and tolerability (including laboratory evaluation of urinalysis, complete blood count, and serum chemistries), ANX007 PK, target engagement, and immunogenicity. Results The mean age overall was 70 years in phase Ia and 68 years in phase Ib. In both studies, no serious adverse events were observed, no non-ocular treatment-emergent adverse events (TEAEs) attributable to study drug were reported, and ocular TEAEs were mild. Intraocular pressure returned to normal levels for all patients within 45 minutes of IVT injection. No clinically significant deviations in laboratory results were observed. In the phase Ib study, C1q in the aqueous humor was reduced to undetectable levels in both the 2.5 mg and 5 mg cohorts 4 weeks after the first ANX007 dose. Conclusions In these studies, single and repeat IVT ANX007 injections were well tolerated and demonstrated full target engagement 4 weeks after dosing with both low and high doses, supporting monthly or less-frequent dosing. Further investigation in neurodegenerative ocular diseases is warranted. Financial Disclosures Proprietary or commercial disclosure may be found after the references.
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Affiliation(s)
- Yang Sun
- Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, California
| | - David Wirta
- Eye Research Foundation, Newport Beach, California
| | | | | | | | | | | | | | - Jeffrey L. Goldberg
- Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, California
- Correspondence: Jeffrey L. Goldberg, MD, PhD, Byers Eye Institute at Stanford, 2452 Watson Ct, Palo Alto, CA 94025.
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Liu F, Wang ZH, Huang W, Xu Y, Sang X, Liu R, Li ZY, Bi YL, Tang L, Peng JY, Wei JR, Miao ZC, Yan JH, Liu S, Yan JH, Liu S. Defects and asymmetries in the visual pathway of non-human primates with natural strabismus and amblyopia. Zool Res 2023; 44:153-168. [PMID: 36484227 PMCID: PMC9841183 DOI: 10.24272/j.issn.2095-8137.2022.254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Strabismus and amblyopia are common ophthalmologic developmental diseases caused by abnormal visual experiences. However, the underlying pathogenesis and visual defects are still not fully understood. Most studies have used experimental interference to establish disease-associated animal models, while ignoring the natural pathophysiological mechanisms. This study was designed to investigate whether natural strabismus and amblyopia are associated with abnormal neurological defects. We screened one natural strabismic monkey ( Macaca fascicularis) and one natural amblyopic monkey from hundreds of monkeys, and retrospectively analyzed one human strabismus case. Neuroimaging, behavioral, neurophysiological, neurostructural, and genovariation features were systematically evaluated using magnetic resonance imaging (MRI), behavioral tasks, flash visual evoked potentials (FVEP), electroretinogram (ERG), optical coherence tomography (OCT), and whole-genome sequencing (WGS), respectively. Results showed that the strabismic patient and natural strabismic and amblyopic monkeys exhibited similar abnormal asymmetries in brain structure, i.e., ipsilateral impaired right hemisphere. Visual behavior, visual function, retinal structure, and fundus of the monkeys were impaired. Aberrant asymmetry in binocular visual function and structure between the strabismic and amblyopic monkeys was closely related, with greater impairment of the left visual pathway. Several similar known mutant genes for strabismus and amblyopia were also identified. In conclusion, natural strabismus and amblyopia are accompanied by abnormal asymmetries of the visual system, especially visual neurophysiological and neurostructural defects. Our results suggest that future therapeutic and mechanistic studies should consider defects and asymmetries throughout the entire visual system.
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Affiliation(s)
- Feng Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Zhong-Hao Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Wanjing Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Ying Xu
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong 510632, China
| | - Xuan Sang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Ruifeng Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Zhou-Yue Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Ya-Lan Bi
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Cambridge CB10 1SD, UK
| | - Lei Tang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Jing-Yi Peng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Jia-Ru Wei
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Zhi-Chao Miao
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Cambridge CB10 1SD, UK,Translational Research Institute of Brain and Brain-Like Intelligence and Department of Anesthesiology, Shanghai Fourth People’s Hospital Affiliated to Tongji University School of Medicine, Shanghai 200081, China
| | - Jian-Hua Yan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China,E-mail:
| | - Sheng Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China,Guangdong Province Key Laboratory of Brain Function and Disease, Guangzhou, Guangdong 510080, China,
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Sharif NA. Degeneration of retina-brain components and connections in glaucoma: Disease causation and treatment options for eyesight preservation. CURRENT RESEARCH IN NEUROBIOLOGY 2022; 3:100037. [PMID: 36685768 PMCID: PMC9846481 DOI: 10.1016/j.crneur.2022.100037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 03/30/2022] [Accepted: 04/01/2022] [Indexed: 01/25/2023] Open
Abstract
Eyesight is the most important of our sensory systems for optimal daily activities and overall survival. Patients who experience visual impairment due to elevated intraocular pressure (IOP) are often those afflicted with primary open-angle glaucoma (POAG) which slowly robs them of their vision unless treatment is administered soon after diagnosis. The hallmark features of POAG and other forms of glaucoma are damaged optic nerve, retinal ganglion cell (RGC) loss and atrophied RGC axons connecting to various brain regions associated with receipt of visual input from the eyes and eventual decoding and perception of images in the visual cortex. Even though increased IOP is the major risk factor for POAG, the disease is caused by many injurious chemicals and events that progress slowly within all components of the eye-brain visual axis. Lowering of IOP mitigates the damage to some extent with existing drugs, surgical and device implantation therapeutic interventions. However, since multifactorial degenerative processes occur during aging and with glaucomatous optic neuropathy, different forms of neuroprotective, nutraceutical and electroceutical regenerative and revitalizing agents and processes are being considered to combat these eye-brain disorders. These aspects form the basis of this short review article.
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Affiliation(s)
- Najam A. Sharif
- Duke-National University of Singapore Medical School, Singapore,Singapore Eye Research Institute (SERI), Singapore,Department of Pharmacology and Neuroscience, University of North Texas Health Sciences Center, Fort Worth, Texas, USA,Department of Pharmaceutical Sciences, Texas Southern University, Houston, TX, USA,Department of Surgery & Cancer, Imperial College of Science and Technology, St. Mary's Campus, London, UK,Department of Pharmacy Sciences, School of School of Pharmacy and Health Professions, Creighton University, Omaha, NE, USA,Ophthalmology Innovation Center, Santen Incorporated, 6401 Hollis Street (Suite #125), Emeryville, CA, 94608, USA,Ophthalmology Innovation Center, Santen Incorporated, 6401 Hollis Street (Suite #125), Emeryville, CA, 94608, USA.
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8
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Noailles A, Kutsyr O, Mayordomo-Febrer A, Lax P, López-Murcia M, Sanz-González SM, Pinazo-Durán MD, Cuenca N. Sodium Hyaluronate-Induced Ocular Hypertension in Rats Damages the Direction-Selective Circuit and Inner/Outer Retinal Plexiform Layers. Invest Ophthalmol Vis Sci 2022; 63:2. [PMID: 35503230 PMCID: PMC9078050 DOI: 10.1167/iovs.63.5.2] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Purpose To assess the changes in retinal morphology in a rat model of chronic glaucoma induced by ocular hypertension. Methods Intraocular pressure (IOP) was surgically increased through weekly injections of sodium hyaluronate (HYA) in the anterior eye chamber of the left eye of male Wistar rats, whereas the right eyes were sham operated (salt solution). During the 10-week experimental period, IOP was measured weekly with a rebound tonometer. Retinal cryosections were prepared for histological/immunohistochemical analysis and morphometry. Results IOP was higher in HYA-treated eyes than in sham-operated eyes along the 10-week period, which was significant from the fourth to the nineth week. Ocular hypertension in HYA-treated eyes was associated with morphologic and morphometric changes in bipolar cells, ON-OFF direction-selective ganglion cells, ON/OFF starburst amacrine cells, and inner plexiform layer sublamina. Conclusions Serial HYA treatment in the rat anterior eye chamber results in mild-to-moderate elevated and sustained IOP and ganglion cell death, which mimics most human open-angle glaucoma hallmarks. The reduced number of direction-selective ganglion cells and starburst amacrine cells accompanied by a deteriorated ON/OFF plexus in this glaucoma model could lend insight to the abnormalities in motion perception observed in patients with glaucoma.
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Affiliation(s)
- Agustina Noailles
- Physiology, Genetics and Microbiology, University of Alicante, Spain.,OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain
| | - Oksana Kutsyr
- Physiology, Genetics and Microbiology, University of Alicante, Spain.,OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain
| | - Aloma Mayordomo-Febrer
- Animal Medicine and Surgery, Faculty of Veterinary Medicine, Universidad CEU Cardenal Herrera, Valencia, Spain.,OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain.,Mixed Research Unit for Visual Health and Veterinary Ophthalmology CEU/FISABIO, Valencia, Spain
| | - Pedro Lax
- Physiology, Genetics and Microbiology, University of Alicante, Spain.,OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain
| | - María López-Murcia
- Animal Medicine and Surgery, Faculty of Veterinary Medicine, Universidad CEU Cardenal Herrera, Valencia, Spain.,Mixed Research Unit for Visual Health and Veterinary Ophthalmology CEU/FISABIO, Valencia, Spain
| | - Silvia M Sanz-González
- OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain.,Cellular and Molecular Ophthalmo-biology Research Group, Department of Surgery, University of Valencia, Valencia, Spain.,Ophthalmic Research Unit "Santiago Grisolía"/FISABIO, Valencia, Spain
| | - María Dolores Pinazo-Durán
- OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain.,Cellular and Molecular Ophthalmo-biology Research Group, Department of Surgery, University of Valencia, Valencia, Spain.,Ophthalmic Research Unit "Santiago Grisolía"/FISABIO, Valencia, Spain
| | - Nicolás Cuenca
- Physiology, Genetics and Microbiology, University of Alicante, Spain.,OFTARED. Spanish Net of Ophthalmic Research. Institute of health Carlos III, Madrid, Spain
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Ribeiro M, McGrady NR, Baratta RO, Del Buono BJ, Schlumpf E, Calkins DJ. Intraocular Delivery of a Collagen Mimetic Peptide Repairs Retinal Ganglion Cell Axons in Chronic and Acute Injury Models. Int J Mol Sci 2022; 23:ijms23062911. [PMID: 35328332 PMCID: PMC8949359 DOI: 10.3390/ijms23062911] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 01/05/2023] Open
Abstract
Vision loss through the degeneration of retinal ganglion cell (RGC) axons occurs in both chronic and acute conditions that target the optic nerve. These include glaucoma, in which sensitivity to intraocular pressure (IOP) causes early RGC axonal dysfunction, and optic nerve trauma, which causes rapid axon degeneration from the site of injury. In each case, degeneration is irreversible, necessitating new therapeutics that protect, repair, and regenerate RGC axons. Recently, we demonstrated the reparative capacity of using collagen mimetic peptides (CMPs) to heal fragmented collagen in the neuronal extracellular milieu. This was an important step in the development of neuronal-based therapies since neurodegeneration involves matrix metalloproteinase (MMP)-mediated remodeling of the collagen-rich environment in which neurons and their axons exist. We found that intraocular delivery of a CMP comprising single-strand fractions of triple helix human type I collagen prevented early RGC axon dysfunction in an inducible glaucoma model. Additionally, CMPs also promoted neurite outgrowth from dorsal root ganglia, challenged in vitro by partial digestion of collagen. Here, we compared the ability of a CMP sequence to protect RGC axons in both inducible glaucoma and optic nerve crush. A three-week +40% elevation in IOP caused a 67% degradation in anterograde transport to the superior colliculus, the primary retinal projection target in rodents. We found that a single intravitreal injection of CMP during the period of IOP elevation significantly reduced this degradation. The same CMP delivered shortly after optic nerve crush promoted significant axonal recovery during the two-week period following injury. Together, these findings support a novel protective and reparative role for the use of CMPs in both chronic and acute conditions affecting the survival of RGC axons in the optic projection to the brain.
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Affiliation(s)
- Marcio Ribeiro
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, AA7103 MCN/VUIIS, 1161 21st Ave. S., Nashville, TN 37232, USA; (M.R.); (N.R.M.)
| | - Nolan R. McGrady
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, AA7103 MCN/VUIIS, 1161 21st Ave. S., Nashville, TN 37232, USA; (M.R.); (N.R.M.)
| | - Robert O. Baratta
- Stuart Therapeutics, Inc., 411 SE Osceola St., Suite 203, Stuart, FL 34994, USA; (R.O.B.); (B.J.D.B.); (E.S.)
| | - Brian J. Del Buono
- Stuart Therapeutics, Inc., 411 SE Osceola St., Suite 203, Stuart, FL 34994, USA; (R.O.B.); (B.J.D.B.); (E.S.)
| | - Eric Schlumpf
- Stuart Therapeutics, Inc., 411 SE Osceola St., Suite 203, Stuart, FL 34994, USA; (R.O.B.); (B.J.D.B.); (E.S.)
| | - David J. Calkins
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, AA7103 MCN/VUIIS, 1161 21st Ave. S., Nashville, TN 37232, USA; (M.R.); (N.R.M.)
- Correspondence: ; Tel.: +1-(615)-936-1424; Fax: +1-(615)-936-6410
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10
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Cáceres-Vélez PR, Hui F, Hercus J, Bui B, Jusuf PR. Restoring the oxidative balance in age-related diseases - An approach in glaucoma. Ageing Res Rev 2022; 75:101572. [PMID: 35065274 DOI: 10.1016/j.arr.2022.101572] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 12/10/2021] [Accepted: 01/18/2022] [Indexed: 02/07/2023]
Abstract
As human life expectancy increases, age-related health issues including neurodegenerative diseases continue to rise. Regardless of genetic or environmental factors, many neurodegenerative conditions share common pathological mechanisms, such as oxidative stress, a hallmark of many age-related health burdens. In this review, we describe oxidative damage and mitochondrial dysfunction in glaucoma, an age-related neurodegenerative eye disease affecting 80 million people worldwide. We consider therapeutic approaches used to counteract oxidative stress in glaucoma, including untapped treatment options such as novel plant-derived antioxidant compounds that can reduce oxidative stress and prevent neuronal loss. We summarize the current pre-clinical models and clinical work exploring the therapeutic potential of a range of candidate plant-derived antioxidant compounds. Finally, we explore advances in drug delivery systems, particular those employing nanotechnology-based carriers which hold significant promise as a carrier for antioxidants to treat age-related disease, thus reviewing the key current state of all of the aspects required towards translation.
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11
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Kumar S, Benavente-Perez A, Ablordeppey R, Lin C, Viswanathan S, Akopian A, Bloomfield SA. A Robust Microbead Occlusion Model of Glaucoma for the Common Marmoset. Transl Vis Sci Technol 2022; 11:14. [PMID: 35019964 PMCID: PMC8762714 DOI: 10.1167/tvst.11.1.14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To establish a robust experimental model of glaucoma in the common marmoset (Callithrix jacchus), a New World primate, using an intracameral microbead injection technique. Methods Elevated intraocular pressure (IOP) was induced by an injection of polystyrene microbeads. Morphologic changes in the retina and optic nerve of glaucomatous eyes were assessed and electroretinogram (ERG) recordings were performed to evaluate functional changes. Results Microbead injections induced a sustained IOP elevation for at least 10 weeks in a reproducible manner. At the end of the 10-week experimental period, there was significant loss of retinal ganglion cells (RGCs) in all quadrants and eccentricities, although it was more prominent in the mid-peripheral and peripheral regions. This was consistent with a thinning of the Retinal nerve fiber layer (RNFL) seen in spectral domain optical coherence tomography scans. Surviving RGCs showed marked changes in morphology, including somatic shrinkage and dendritic atrophy. Retinas also showed significant gliosis. The amplitude of the ERG photopic negative response, with subsequent a- and b-wave changes, was reduced in glaucomatous eyes. The optic nerve of glaucomatous eyes showed expanded cupping, disorganization of the astrocytic matrix, axonal loss, and gliosis. Conclusions We developed a robust and reproducible model of glaucoma in the marmoset. The model exhibits both structural and functional alterations of retina and optic nerve characteristic of glaucoma in humans and animal models. Translational Relevance The glaucoma model in the marmoset described here forms a robust method to study the disease etiology, progression, and potential therapies in a nonhuman primate, allowing for more effective translation of animal data to humans.
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Affiliation(s)
- Sandeep Kumar
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Alexandra Benavente-Perez
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Reynolds Ablordeppey
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Carol Lin
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Suresh Viswanathan
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Abram Akopian
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Stewart A Bloomfield
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
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12
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Guo J, Liu H, Fu L. MicroRNA-124 ameliorates autophagic dysregulation in glaucoma via regulation of P2X7-mediated Akt/mTOR signaling. Cutan Ocul Toxicol 2021; 41:43-48. [PMID: 34844494 DOI: 10.1080/15569527.2021.2003378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Glaucoma is a neurodegenerative disease that leads to irrevocable blindness. In glaucoma, even though axonal damage and function deficit culminates in retinal ganglion cell (RGC) degeneration, our knowledge on the autophagic mechanisms and the role of specific microRNAs is still limited. In this study, we investigated the role of microRNA-124 (MiR-124) in surgically induced glaucomatous neurodegeneration using a mouse model. Animals were segregated into four cohorts of 10 each: (i) sham-operated (n = 10); (ii) surgically induced glaucoma (SIG; n = 10); (iii) SIG + miR-124 mimic; (iv) SIG + miR-NC. Chronic elevation of intraocular pressure (IOP) is a critical risk factor for glaucoma. In our study, chronically elevated IOP caused anterograde axonal transport (AAT) defect, increased the autophagic activity (manifested by significantly (p < 0.05) increased LC3-II/LC3-I ratio, beclin-1 and Atg7 protein expressions) and also downmodulated the protein expression of p-Akt and p-mTOR, mediated by the purinergic P2 receptor subtype 7 (P2X7) upmodulation-leading to retinal degeneration. However, administration of miR-124 mimic improved the retinal integrity and function, as indicated by the improved AAT function, normalized the autophagic dysfunction, modulated the protein expression of P2X7-mediated p-Akt and p-mTOR. Hence, we propose that development of miR-124-based advanced therapies might be a potential avenue in the treatment of glaucomatous neurodegeneration.
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Affiliation(s)
- Jun Guo
- Department of Ophthalmology, Zhongshan Hospital Affiliated with Dalian University, Dalian, China
| | - Haojie Liu
- Department of Ophthalmology, Zhongshan Hospital Affiliated with Dalian University, Dalian, China
| | - Lin Fu
- Department of Ophthalmology, Zhongshan Hospital Affiliated with Dalian University, Dalian, China
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13
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McGrady NR, Pasini S, Baratta RO, Del Buono BJ, Schlumpf E, Calkins DJ. Restoring the Extracellular Matrix: A Neuroprotective Role for Collagen Mimetic Peptides in Experimental Glaucoma. Front Pharmacol 2021; 12:764709. [PMID: 34795592 PMCID: PMC8592892 DOI: 10.3389/fphar.2021.764709] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/19/2021] [Indexed: 11/24/2022] Open
Abstract
Optic neuropathies are a major cause of visual disabilities worldwide, causing irreversible vision loss through the degeneration of retinal ganglion cell (RGC) axons, which comprise the optic nerve. Chief among these is glaucoma, in which sensitivity to intraocular pressure (IOP) leads to RGC axon dysfunction followed by outright degeneration of the optic projection. Current treatments focus entirely on lowering IOP through topical hypotensive drugs, surgery to facilitate aqueous fluid outflow, or both. Despite this investment in time and resources, many patients continue to lose vision, underscoring the need for new therapeutics that target neurodegeneration directly. One element of progression in glaucoma involves matrix metalloproteinase (MMP) remodeling of the collagen-rich extracellular milieu of RGC axons as they exit the retina through the optic nerve head. Thus, we investigated the ability of collagen mimetic peptides (CMPs) representing various single strand fractions of triple helix human type I collagen to protect RGC axons in an inducible model of glaucoma. First, using dorsal root ganglia maintained in vitro on human type I collagen, we found that multiple CMPs significantly promote neurite outgrowth (+35%) compared to vehicle following MMP-induced fragmentation of the α1(I) and α2(I) chains. We then applied CMP to adult mouse eyes in vivo following microbead occlusion to elevate IOP and determined its influence on anterograde axon transport to the superior colliculus, the primary RGC projection target in rodents. In glaucoma models, sensitivity to IOP causes early degradation in axon function, including anterograde transport from retina to central brain targets. We found that CMP treatment rescued anterograde transport following a 3-week +50% elevation in IOP. These results suggest that CMPs generally may represent a novel therapeutic to supplement existing treatments or as a neuroprotective option for patients who do not respond to IOP-lowering regimens.
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Affiliation(s)
- Nolan R McGrady
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Silvia Pasini
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
| | | | | | - Eric Schlumpf
- Stuart Therapeutics, Inc., Stuart, FL, United States
| | - David J Calkins
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
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14
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Guo M, Schwartz TD, Dunaief JL, Cui QN. Myeloid cells in retinal and brain degeneration. FEBS J 2021; 289:2337-2361. [PMID: 34478598 PMCID: PMC8891394 DOI: 10.1111/febs.16177] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 08/06/2021] [Accepted: 09/02/2021] [Indexed: 12/11/2022]
Abstract
Retinal inflammation underlies multiple prevalent ocular and neurological diseases. Similar inflammatory processes are observed in glaucomatous optic neuropathy, age-related macular degeneration, retinitis pigmentosa, posterior uveitis, Alzheimer's disease, and Parkinson's disease. In particular, human and animal studies have demonstrated the important role microglia/macrophages play in initiating and maintaining a pro-inflammatory environment in degenerative processes impacting vision. On the other hand, microglia have also been shown to have a protective role in multiple central nervous system diseases. Identifying the mechanisms underlying cell dysfunction and death is the first step toward developing novel therapeutics for these diseases impacting the central nervous system. In addition to reviewing recent key studies defining important mediators of retinal inflammation, with an emphasis on translational studies that bridge this research from bench to bedside, we also highlight a promising therapeutic class of medications, the glucagon-like peptide-1 receptor agonists. Finally, we propose areas where additional research is necessary to identify mechanisms that can be modulated to shift the balance from a neurotoxic to a neuroprotective retinal environment.
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Affiliation(s)
- Michelle Guo
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Turner D Schwartz
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Joshua L Dunaief
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Qi N Cui
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
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15
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Amirmokhtari N, Foresi BD, Dewan SS, Bouhenni RA, Smith MA. Absence of Cytochrome P450-1b1 Increases Susceptibility of Pressure-Induced Axonopathy in the Murine Retinal Projection. Front Cell Dev Biol 2021; 9:636321. [PMID: 33748124 PMCID: PMC7973214 DOI: 10.3389/fcell.2021.636321] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 01/25/2021] [Indexed: 01/14/2023] Open
Abstract
Mutations in the cytochrome P450-1B1 (Cyp1b1) gene is a common genetic predisposition associated with various human glaucomas, most prominently in primary congenital glaucoma (PCG). The role of Cyp1b1 in the eye is largely unknown, however, its absence appears to drive the maldevelopment of anterior eye structures responsible for aqueous fluid drainage in murine models. Nevertheless, vision loss in glaucoma ultimately results from the structural and functional loss of retinal ganglion cells (RGCs). Cyp1b1’s influence in the development and support of retinal ganglion cell structure and function under normal conditions or during stress, such as elevated ocular pressure; the most common risk factor in glaucoma, remains grossly unknown. Thus, to determine the role of Cyp1b1 in normal retinal projection development we first assessed the strucutrual integrity of RGCs in the retina, optic nerve, and superior colliculus in un-manipulated (naïve) Cyp1b1-knockout (Cyp1b1–/–) mice. In addition, in a separate cohort of Cyp1b1–/– and wildtype mice, we elevated and maintained intraocular pressure (IOP) at glaucomatous levels for 5-weeks, after which we compared RGC density, node of Ranvier morphology, and axonal transport between the genotypes. Our results demonstrate that naïve Cyp1b1–/– mice develop an anatomically intact retinal projection absent of overt glaucomatous pathology. Following pressure elevation, Cyp1b1–/– accelerated degradation of axonal transport from the retina to the superior colliculus and altered morphology of the nodes of Ranvier and adjacent paranodes in the optic nerves. Together this data suggests the absence Cyp1b1 expression alone is insufficient to drive murine glaucomatous pathology, however, may increase the vulnerability of retinal axons to disease relevant elevations in IOP.
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Affiliation(s)
- Naseem Amirmokhtari
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH, United States.,Integrated Pharmaceutical Medicine Graduate Program, Northeast Ohio Medical University, Rootstown, OH, United States
| | - Brian D Foresi
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH, United States
| | - Shiv S Dewan
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH, United States
| | - Rachida A Bouhenni
- Rebecca D. Considine Research Institute, Vision Center, Akron Children's Hospital, Akron, OH, United States
| | - Matthew A Smith
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH, United States.,Rebecca D. Considine Research Institute, Vision Center, Akron Children's Hospital, Akron, OH, United States
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16
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Calkins DJ. Adaptive responses to neurodegenerative stress in glaucoma. Prog Retin Eye Res 2021; 84:100953. [PMID: 33640464 DOI: 10.1016/j.preteyeres.2021.100953] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 02/08/2021] [Accepted: 02/19/2021] [Indexed: 12/12/2022]
Abstract
Glaucoma causes loss of vision through degeneration of the retinal ganglion cell (RGC) projection to the brain. The disease is characterized by sensitivity to intraocular pressure (IOP) conveyed at the optic nerve head, through which RGC axons pass unmyelinated to form the optic nerve. From this point, a pathogenic triumvirate comprising inflammatory, oxidative, and metabolic stress influence both proximal structures in the retina and distal structures in the optic projection. This review focuses on metabolic stress and how the optic projection may compensate through novel adaptive mechanisms to protect excitatory signaling to the brain. In the retina and proximal nerve head, the unmyelinated RGC axon segment is energy-inefficient, which leads to increased demand for adenosine-5'-triphosphate (ATP) at the risk of vulnerability to Ca2+-related metabolic and oxidative pressure. This vulnerability may underlie the bidirectional nature of progression. However, recent evidence highlights that the optic projection in glaucoma is not passive but rather demonstrates adaptive processes that may push back against neurodegeneration. In the retina, even as synaptic and dendritic pruning ensues, early progression involves enhanced excitability of RGCs. Enhancement involves depolarization of the resting membrane potential and increased response to light, independent of RGC morphological type. This response is axogenic, arising from increased levels and translocation of voltage-gated sodium channels (NaV) in the unmyelinated segment. During this same early period, large-scale networks of gap-junction coupled astrocytes redistribute metabolic resources to the optic projection stressed by elevated IOP to slow loss of axon function. This redistribution may reflect more local remodeling, as astrocyte processes respond to focal metabolic duress by boosting glycogen turnover in response to axonal activity in an effort to promote survival of the healthiest axons. Both enhanced excitability and metabolic redistribution are transient, indicating that the same adaptive mechanisms that apparently serve to slow progression ultimately may be too expensive for the system to sustain over longer periods.
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Affiliation(s)
- David J Calkins
- The Vanderbilt Eye Institute, Nashville, TN, USA; Vanderbilt Vision Research Center, Vanderbilt University Medical Center, 1161 21st Ave S, AA7100 Medical Center North Nashville, Tennessee, 37232, USA.
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17
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Baudouin C, Kolko M, Melik-Parsadaniantz S, Messmer EM. Inflammation in Glaucoma: From the back to the front of the eye, and beyond. Prog Retin Eye Res 2020; 83:100916. [PMID: 33075485 DOI: 10.1016/j.preteyeres.2020.100916] [Citation(s) in RCA: 159] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 10/09/2020] [Accepted: 10/13/2020] [Indexed: 02/08/2023]
Abstract
The pathophysiology of glaucoma is complex, multifactorial and not completely understood. Elevated intraocular pressure (IOP) and/or impaired retinal blood flow may cause initial optic nerve damage. In addition, age-related oxidative stress in the retina concurrently with chronic mechanical and vascular stress is crucial for the initiation of retinal neurodegeneration. Oxidative stress is closely related to cell senescence, mitochondrial dysfunction, excitotoxicity, and neuroinflammation, which are involved in glaucoma progression. Accumulating evidence from animal glaucoma models and from human ocular samples suggests a dysfunction of the para-inflammation in the retinal ganglion cell layer and the optic nerve head. Moreover, quite similar mechanisms in the anterior chamber could explain the trabecular meshwork dysfunction and the elevated IOP in primary open-angle glaucoma. On the other hand, ocular surface disease due to topical interventions is the most prominent and visible consequence of inflammation in glaucoma, with a negative impact on filtering surgery failure, topical treatment efficacy, and possibly on inflammation in the anterior segment. Consequently, glaucoma appears as an outstanding eye disease where inflammatory changes may be present to various extents and consequences along the eye structure, from the ocular surface to the posterior segment, and the visual pathway. Here we reviewed the inflammatory processes in all ocular structures in glaucoma from the back to the front of the eye and beyond. Our approach was to explain how para-inflammation is necessary to maintain homoeostasis, and to describe abnormal inflammatory findings observed in glaucomatous patients or in animal glaucoma models, supporting the hypothesis of a dysregulation of the inflammatory balance toward a pro-inflammatory phenotype. Possible anti-inflammatory therapeutic approaches in glaucoma are also discussed.
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Affiliation(s)
- Christophe Baudouin
- Quinze-Vingts National Ophthalmology Hospital, INSERM-DGOS CIC 1423, IHU Foresight, Paris, France; Sorbonne Université, INSERM, CNRS, Institut de La Vision, Paris, France; Department of Ophthalmology, Ambroise Paré Hospital, APHP, Université de Versailles Saint-Quentin en Yvelines, Boulogne-Billancourt, France.
| | - Miriam Kolko
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark; Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet-Glostrup, Glostrup, Denmark
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18
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Chan ASY, Tun TA, Allen JC, Lynn MN, Tun SBB, Barathi VA, Girard MJA, Aung T, Aihara M. Longitudinal assessment of optic nerve head changes using optical coherence tomography in a primate microbead model of ocular hypertension. Sci Rep 2020; 10:14709. [PMID: 32895414 PMCID: PMC7477239 DOI: 10.1038/s41598-020-71555-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/19/2020] [Indexed: 11/16/2022] Open
Abstract
In humans, the longitudinal characterisation of early optic nerve head (ONH) damage in ocular hypertension (OHT) is difficult as patients with glaucoma usually have structural ONH damage at the time of diagnosis. Previous studies assessed glaucomatous ONH cupping by measuring the anterior lamina cribrosa depth (LCD) and minimal rim width (MRW) using optical coherence tomography (OCT). In this study, we induced OHT by repeated intracameral microbead injections in 16 cynomolgus primates (10 unilateral; 6 bilateral) and assessed the structural changes of the ONH longitudinally to observe early changes. Elevated intraocular pressure (IOP) in OHT eyes was maintained for 7 months and serial OCT measurements were performed during this period. The mean IOP was significantly elevated in OHT eyes when compared to baseline and compared to the control eyes. Thinner MRW and deeper LCD values from baseline were observed in OHT eyes with the greatest changes seen between month 1 and month 2 of OHT. Both the mean and maximum IOP values were significant predictors of MRW and LCD changes, although the maximum IOP was a slightly better predictor. We believe that this model could be useful to study IOP-induced early ONH structural damage which is important for understanding glaucoma pathogenesis.
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Affiliation(s)
- Anita S Y Chan
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore. .,Department of Ophthalmology, University of Tokyo, Tokyo, Japan.
| | - Tin Aung Tun
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Ophthalmic Engineering & Innovation Laboratory (OEIL), Singapore Eye Research Institute, Singapore, Singapore
| | | | - Myoe Naing Lynn
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Sai Bo Bo Tun
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Veluchamy Amutha Barathi
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Duke-NUS Medical School, Singapore, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Michaël J A Girard
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Ophthalmic Engineering & Innovation Laboratory (OEIL), Singapore Eye Research Institute, Singapore, Singapore
| | - Tin Aung
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Duke-NUS Medical School, Singapore, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Makoto Aihara
- Department of Ophthalmology, University of Tokyo, Tokyo, Japan
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19
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Wójcik-Gryciuk A, Gajewska-Woźniak O, Kordecka K, Boguszewski PM, Waleszczyk W, Skup M. Neuroprotection of Retinal Ganglion Cells with AAV2-BDNF Pretreatment Restoring Normal TrkB Receptor Protein Levels in Glaucoma. Int J Mol Sci 2020; 21:ijms21176262. [PMID: 32872441 PMCID: PMC7504711 DOI: 10.3390/ijms21176262] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/26/2020] [Accepted: 08/27/2020] [Indexed: 02/07/2023] Open
Abstract
Intravitreal delivery of brain-derived neurotrophic factor (BDNF) by injection of recombinant protein or by gene therapy can alleviate retinal ganglion cell (RGC) loss after optic nerve injury (ONI) or laser-induced ocular hypertension (OHT). In models of glaucoma, BDNF therapy can delay or halt RGCs loss, but this protection is time-limited. The decreased efficacy of BDNF supplementation has been in part attributed to BDNF TrkB receptor downregulation. However, whether BDNF overexpression causes TrkB downregulation, impairing long-term BDNF signaling in the retina, has not been conclusively proven. After ONI or OHT, when increased retinal BDNF was detected, a concomitant increase, no change or a decrease in TrkB was reported. We examined quantitatively the retinal concentrations of the TrkB protein in relation to BDNF, in a course of adeno-associated viral vector gene therapy (AAV2-BDNF), using a microbead trabecular occlusion model of glaucoma. We show that unilateral glaucoma, with intraocular pressure ( IOP) increased for five weeks, leads to a bilateral decrease of BDNF in the retina at six weeks, accompanied by up to four-fold TrkB upregulation, while a moderate BDNF overexpression in a glaucomatous eye triggers changes that restore normal TrkB concentrations, driving signaling towards long-term RGCs neuroprotection. We conclude that for glaucoma therapy, the careful selection of the appropriate BDNF concentration is the main factor securing the long-term responsiveness of RGCs and the maintenance of normal TrkB levels.
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Affiliation(s)
- Anna Wójcik-Gryciuk
- Laboratory of Neurobiology of Vision, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland; (A.W.-G.); (K.K.); (W.W.)
- Mediq Clinic, 05-120 Legionowo, Poland
| | - Olga Gajewska-Woźniak
- Group of Restorative Neurobiology, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland;
| | - Katarzyna Kordecka
- Laboratory of Neurobiology of Vision, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland; (A.W.-G.); (K.K.); (W.W.)
| | - Paweł M. Boguszewski
- Laboratory of Behavioral Methods, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland;
| | - Wioletta Waleszczyk
- Laboratory of Neurobiology of Vision, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland; (A.W.-G.); (K.K.); (W.W.)
| | - Małgorzata Skup
- Group of Restorative Neurobiology, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland;
- Correspondence:
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20
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Lambert WS, Pasini S, Collyer JW, Formichella CR, Ghose P, Carlson BJ, Calkins DJ. Of Mice and Monkeys: Neuroprotective Efficacy of the p38 Inhibitor BIRB 796 Depends on Model Duration in Experimental Glaucoma. Sci Rep 2020; 10:8535. [PMID: 32444682 PMCID: PMC7244559 DOI: 10.1038/s41598-020-65374-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 05/04/2020] [Indexed: 01/23/2023] Open
Abstract
Glaucoma is a group of optic neuropathies associated with aging and sensitivity to intraocular pressure (IOP). Early progression involves retinal ganglion cell (RGC) axon dysfunction that precedes frank degeneration. Previously we demonstrated that p38 MAPK inhibition abates axonal dysfunction and slows degeneration in the inducible microbead occlusion model of glaucoma in rat. Here, we assessed the neuroprotective effect of topical eye delivery of the p38 MAPK inhibitor BIRB 796 in three models of glaucoma (microbead occlusion in rat and squirrel monkey and the genetic DBA/2 J mouse model) with distinct durations of IOP elevation. While BIRB 796 did not influence IOP, treatment over four weeks in rats prevented degradation of anterograde axonal transport to the superior colliculus and degeneration in the optic nerve. Treatment over months in the chronic DBA/2 J model and in the squirrel monkey model reduced expression and activation of p38 downstream targets in the retina and brain but did not rescue RGC axon transport or degeneration, suggesting the efficacy of BIRB 796 in preventing associated degeneration of the RGC projection depends on the duration of the experimental model. These results emphasize the importance of evaluating potential therapeutic compounds for neuroprotection in multiple models using elongated treatment paradigms for an accurate assessment of efficacy.
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Affiliation(s)
- Wendi S Lambert
- The Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, 37232-2337, USA
| | - Silvia Pasini
- The Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, 37232-2337, USA
| | - John W Collyer
- The Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, 37232-2337, USA
| | - Cathryn R Formichella
- The Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, 37232-2337, USA
| | - Purnima Ghose
- The Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, 37232-2337, USA
| | - Brian J Carlson
- The Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, 37232-2337, USA
| | - David J Calkins
- The Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, 37232-2337, USA.
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21
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Liu Y, Wang J, Jin X, Xin Z, Wu X, Tong X, Tao Y, Wang D. A novel rat model of ocular hypertension by a single intracameral injection of cross-linked hyaluronic acid hydrogel (Healaflow ® ). Basic Clin Pharmacol Toxicol 2020; 127:361-370. [PMID: 32383327 DOI: 10.1111/bcpt.13430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 04/26/2020] [Accepted: 05/03/2020] [Indexed: 12/28/2022]
Abstract
To create a novel animal model of ocular hypertension via the intracameral injection of Healaflow. Unilateral chronic ocular hypertension model of rats was created by the intracameral injection of 3 μL Healaflow. The IOP of subjects was monitored. Dynamic morphological changes were evaluated by fundus imaging, OCT and histological examination. Visual function changes were measured by electroretinography and flash visual-evoked potentials. 24 and 72 hours after injection, the retinal tissue was collected for transcriptome analysis. The expression levels of related genes and proteins were further evaluated by qRT-PCR and Western blotting. The IOP peaked within 1 day after a single intracameral injection of Healaflow and then decreased gradually within 4 weeks. Furthermore, the persistently degenerating retinal ganglion cells occurred within 4 weeks. The visual function of these rats was also impaired. The results of transcriptome analyses, qRT-PCR and Western blotting showed that the expression levels of B2m, Ikzf1 and Stat3 were up-regulated, while the expression levels of Six3 and Prss56 were down-regulated in the retinal tissues. Intracameral injection of Healaflow is an effective approach to induce glaucomatous neurodegeneration in rats. Six3 and Prss56 may be involved in the pathogenesis of progressive glaucomatous damage.
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Affiliation(s)
- Ying Liu
- Department of ophthalmology, The First Medical Center, Chinese PLA General Hospital, Beijing, China.,Department of Ophthalmology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, China
| | - Jichen Wang
- First Clinical Medical College, Anhui Medical University, Hefei, China
| | - Xin Jin
- Department of ophthalmology, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Zhiyuan Xin
- Department of ophthalmology, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Xing Wu
- Department of ophthalmology, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Xu Tong
- Department of ophthalmology, The First Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Ye Tao
- Department of Ophthalmology, Henan Provincial People's Hospital, People's Hospital, Zhengzhou University, Zhengzhou, China
| | - Dajiang Wang
- Department of ophthalmology, The First Medical Center, Chinese PLA General Hospital, Beijing, China
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Abstract
Retinal degenerative diseases caused by photoreceptor cell death are major causes of irreversible vision loss. As only primates have a macula, the nonhuman primate (NHP) models have a crucial role not only in revealing biological mechanisms underlying high-acuity vision but also in the development of therapies. Successful translation of basic research findings into clinical trials and, moreover, approval of the first therapies for blinding inherited and age-related retinal dystrophies has been reported in recent years. This article explores the value of the NHP models in understanding human vision and reviews their contribution to the development of innovative therapeutic strategies to save and restore vision.
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