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Chen TE, Lo J, Huang SP, Chang KC, Liu PL, Wu HE, Chen YR, Chang YC, Liu CC, Lee PY, Lai YH, Wu PC, Wang SC, Li CY. Glaucine inhibits hypoxia-induced angiogenesis and attenuates LPS-induced inflammation in human retinal pigment epithelial ARPE-19 cells. Eur J Pharmacol 2024; 981:176883. [PMID: 39128809 DOI: 10.1016/j.ejphar.2024.176883] [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: 09/16/2023] [Revised: 07/24/2024] [Accepted: 08/08/2024] [Indexed: 08/13/2024]
Abstract
Glaucine is an aporphine alkaloid with anti-inflammatory, bronchodilator and anti-cancer activities. However, the effects of glaucine in the regulation of age-related macular degeneration (AMD) remain unclear. Herein, we aimed to investigate the anti-angiogenetic and anti-inflammatory effects of glaucine in ARPE-19 cells. ARPE-19 cells were treated with N-(methoxyoxoacetyl)-glycine, methyl ester (DMOG) and cobalt chloride (CoCl2) for induction of hypoxia, while lipopolysaccharide (LPS) treatment was used for elicitation of inflammatory response. Cell viability was analyzed using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay. The expression of hypoxia-inducible factor (HIF-1α) and vascular endothelial growth factor (VEGF) were measured by Western blot. The secretion of VEGF, interleukin (IL)-6 and monocyte chemoattractant protein-1 (MCP-1) was detected using enzyme-linked immunosorbent assay (ELISA). Human umbilical vein endothelial cells (HUVECs) were used for tube formation analysis. Expression of HIF-1α and secretion of VEGF were significantly increased under DMOG and CoCl2 induction, whereas glaucine significantly attenuated both HIF-1α expression and VEGF secretion by DMOG- and CoCl2-induced ARPE-19 cells. In addition, glaucine suppressed the tube formation by DMOG- and CoCl2-induced HUVEC cells. Moreover, glaucine also attenuated the production of IL-6 and MCP-1 by LPS-induced ARPE-19 cells. This study indicated that glaucine exhibited anti-angiogenic and anti-inflammatory effects, suggesting that glaucine might have benefits for the treatment of AMD.
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Affiliation(s)
- Ting-En Chen
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Jung Lo
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, 83301, Taiwan
| | - Shu-Pin Huang
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Urology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Institute of Medical Science and Technology, College of Medicine, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan
| | - Kun-Che Chang
- Department of Ophthalmology, Louis J. Fox Center for Vision Restoration, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA; Department of Neurobiology, Center of Neuroscience, University of Pittsburgh School of Medicine, Pitts-burgh, PA, 15213, USA
| | - Po-Len Liu
- Department of Respiratory Therapy, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Hsin-En Wu
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Yuan-Ru Chen
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Yo-Chen Chang
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Ophthalmology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Ching-Chih Liu
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Ophthalmology, Chi Mei Medical Center, Tainan 71004, Taiwan
| | - Po-Yen Lee
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Yu-Hung Lai
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Pei-Chang Wu
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, 83301, Taiwan
| | - Shu-Chi Wang
- Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, 80756, Taiwan.
| | - Chia-Yang Li
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, 80756, Taiwan.
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Chucair-Elliott AJ, Ocañas SR, Pham K, Machalinski A, Plafker S, Stout MB, Elliott MH, Freeman WM. Age- and sex- divergent translatomic responses of the mouse retinal pigmented epithelium. Neurobiol Aging 2024; 140:41-59. [PMID: 38723422 PMCID: PMC11173338 DOI: 10.1016/j.neurobiolaging.2024.04.012] [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: 10/24/2023] [Revised: 04/22/2024] [Accepted: 04/23/2024] [Indexed: 05/18/2024]
Abstract
Aging is the main risk factor for age-related macular degeneration (AMD), a retinal neurodegenerative disease that leads to irreversible blindness, particularly in people over 60 years old. Retinal pigmented epithelium (RPE) atrophy is an AMD hallmark. Genome-wide chromatin accessibility, DNA methylation, and gene expression studies of AMD and control RPE demonstrate epigenomic/transcriptomic changes occur during AMD onset and progression. However, mechanisms by which molecular alterations of normal aging impair RPE function and contribute to AMD pathogenesis are unclear. Here, we specifically interrogate the RPE translatome with advanced age and across sexes in a novel RPE reporter mouse model. We find differential age- and sex- associated transcript expression with overrepresentation of pathways related to inflammation in the RPE. Concordant with impaired RPE function, the phenotypic changes in the aged translatome suggest that aged RPE becomes immunologically active, in both males and females, with some sex-specific signatures, which supports the need for sex representation for in vivo studies.
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Affiliation(s)
- Ana J Chucair-Elliott
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.
| | - Sarah R Ocañas
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Kevin Pham
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Adeline Machalinski
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Scott Plafker
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Michael B Stout
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Michael H Elliott
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Willard M Freeman
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA; Oklahoma City Veterans Affairs Medical Center, Oklahoma City, OK, USA.
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3
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Keenan TDL, Bailey C, Abraham M, Orndahl C, Menezes S, Bellur S, Arunachalam T, Kangale-Whitney C, Srinivas S, Karamat A, Nittala M, Cunningham D, Jeffrey BG, Wiley HE, Thavikulwat AT, Sadda S, Cukras CA, Chew EY, Wong WT. Phase 2 Trial Evaluating Minocycline for Geographic Atrophy in Age-Related Macular Degeneration: A Nonrandomized Controlled Trial. JAMA Ophthalmol 2024; 142:345-355. [PMID: 38483382 PMCID: PMC10941022 DOI: 10.1001/jamaophthalmol.2024.0118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 12/20/2023] [Indexed: 03/17/2024]
Abstract
Importance Existing therapies to slow geographic atrophy (GA) enlargement in age-related macular degeneration (AMD) have relatively modest anatomic efficacy, require intravitreal administration, and increase the risk of neovascular AMD. Additional therapeutic approaches are desirable. Objective To evaluate the safety and possible anatomic efficacy of oral minocycline, a microglial inhibitor, for the treatment of GA in AMD. Design, Setting, and Participants This was a phase 2, prospective, single-arm, 45-month, nonrandomized controlled trial conducted from December 2016 to April 2023. Patients with GA from AMD in 1 or both eyes were recruited from the National Institutes of Health (Bethesda, Maryland) and Bristol Eye Hospital (Bristol, UK). Study data were analyzed from September 2022 to May 2023. Intervention After a 9-month run-in phase, participants began oral minocycline, 100 mg, twice daily for 3 years. Main Outcomes and Measures The primary outcome measure was the difference in rate of change of square root GA area on fundus autofluorescence between the 24-month treatment phase and 9-month run-in phase. Results Of the 37 participants enrolled (mean [SD] age, 74.3 [7.6] years; 21 female [57%]), 36 initiated the treatment phase. Of these participants, 21 (58%) completed at least 33 months, whereas 15 discontinued treatment (8 by request, 6 for adverse events/illness, and 1 death). Mean (SE) square root GA enlargement rate in study eyes was 0.31 (0.03) mm per year during the run-in phase and 0.28 (0.02) mm per year during the treatment phase. The primary outcome measure of mean (SE) difference in enlargement rates between the 2 phases was -0.03 (0.03) mm per year (P = .39). Similarly, secondary outcome measures of GA enlargement rate showed no differences between the 2 phases. The secondary outcome measures of mean difference in rate of change between 2 phases were 0.2 letter score per month (95% CI, -0.4 to 0.9; P = .44) for visual acuity and 0.7 μm per month (-0.4 to 1.8; P = .20) for subfoveal retinal thickness. Of the 129 treatment-emergent adverse events among 32 participants, 49 (38%) were related to minocycline (with no severe or ocular events), including elevated thyrotropin level (15 participants) and skin hyperpigmentation/discoloration (8 participants). Conclusions and Relevance In this phase 2 nonrandomized controlled trial, oral minocycline was not associated with a decrease in GA enlargement over 24 months, compared with the run-in phase. This observation was consistent across primary and secondary outcome measures. Oral minocycline at this dose is likely not associated with slower rate of enlargement of GA in AMD.
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Affiliation(s)
| | | | | | | | | | - Sunil Bellur
- National Eye Institute, National Institutes of Health, Bethesda, Maryland
| | | | | | | | | | | | - Denise Cunningham
- National Eye Institute, National Institutes of Health, Bethesda, Maryland
| | - Brett G. Jeffrey
- National Eye Institute, National Institutes of Health, Bethesda, Maryland
| | - Henry E. Wiley
- National Eye Institute, National Institutes of Health, Bethesda, Maryland
- Now with Genentech Inc, South San Francisco, California
| | | | - SriniVas Sadda
- Doheny Eye Institute, Pasadena, California
- University of California, Los Angeles, Los Angeles
| | | | - Emily Y. Chew
- National Eye Institute, National Institutes of Health, Bethesda, Maryland
| | - Wai T. Wong
- National Eye Institute, National Institutes of Health, Bethesda, Maryland
- Now with Janssen Research and Development LLC, Brisbane, California
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4
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Liu D, Liu Z, Liao H, Chen ZS, Qin B. Ferroptosis as a potential therapeutic target for age-related macular degeneration. Drug Discov Today 2024; 29:103920. [PMID: 38369100 DOI: 10.1016/j.drudis.2024.103920] [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: 12/11/2023] [Revised: 02/11/2024] [Accepted: 02/14/2024] [Indexed: 02/20/2024]
Abstract
Cell death plays a crucial part in the process of age-related macular degeneration (AMD), but its mechanisms remain elusive. Accumulating evidence suggests that ferroptosis, a novel form of regulatory cell death characterized by iron-dependent accumulation of lipid hydroperoxides, has a crucial role in the pathogenesis of AMD. Numerous studies have suggested that ferroptosis participates in the degradation of retinal cells and accelerates the progression of AMD. Furthermore, inhibitors of ferroptosis exhibit notable protective effects in AMD, underscoring the significance of ferroptosis as a pivotal mechanism in the death of retinal cells during the process of AMD. This review aims to summarize the molecular mechanisms of ferroptosis in AMD, enumerate potential inhibitors and discuss the challenges and future opportunities associated with targeting ferroptosis as a therapeutic strategy, providing important information references and insights for the prevention and treatment of AMD.
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Affiliation(s)
- Dongcheng Liu
- Shenzhen Aier Eye Hospital, Aier Eye Hospital, Jinan University, Shenzhen, China; Shenzhen Aier Ophthalmic Technology Institute, Shenzhen, China
| | - Ziling Liu
- Shenzhen Aier Eye Hospital, Aier Eye Hospital, Jinan University, Shenzhen, China; Shenzhen Aier Ophthalmic Technology Institute, Shenzhen, China
| | - Hongxia Liao
- Shenzhen Aier Eye Hospital, Aier Eye Hospital, Jinan University, Shenzhen, China; Shenzhen Aier Ophthalmic Technology Institute, Shenzhen, China
| | - Zhe-Sheng Chen
- College of Pharmacy and Health Sciences, St. John's University, Queens, New York, USA.
| | - Bo Qin
- Shenzhen Aier Eye Hospital, Aier Eye Hospital, Jinan University, Shenzhen, China; Shenzhen Aier Ophthalmic Technology Institute, Shenzhen, China; Aier Eye Hospital, Tianjin University, Tianjin, China.
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5
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Abd El-Khalek AA, Balaha HM, Alghamdi NS, Ghazal M, Khalil AT, Abo-Elsoud MEA, El-Baz A. A concentrated machine learning-based classification system for age-related macular degeneration (AMD) diagnosis using fundus images. Sci Rep 2024; 14:2434. [PMID: 38287062 PMCID: PMC10825213 DOI: 10.1038/s41598-024-52131-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 01/14/2024] [Indexed: 01/31/2024] Open
Abstract
The increase in eye disorders among older individuals has raised concerns, necessitating early detection through regular eye examinations. Age-related macular degeneration (AMD), a prevalent condition in individuals over 45, is a leading cause of vision impairment in the elderly. This paper presents a comprehensive computer-aided diagnosis (CAD) framework to categorize fundus images into geographic atrophy (GA), intermediate AMD, normal, and wet AMD categories. This is crucial for early detection and precise diagnosis of age-related macular degeneration (AMD), enabling timely intervention and personalized treatment strategies. We have developed a novel system that extracts both local and global appearance markers from fundus images. These markers are obtained from the entire retina and iso-regions aligned with the optical disc. Applying weighted majority voting on the best classifiers improves performance, resulting in an accuracy of 96.85%, sensitivity of 93.72%, specificity of 97.89%, precision of 93.86%, F1 of 93.72%, ROC of 95.85%, balanced accuracy of 95.81%, and weighted sum of 95.38%. This system not only achieves high accuracy but also provides a detailed assessment of the severity of each retinal region. This approach ensures that the final diagnosis aligns with the physician's understanding of AMD, aiding them in ongoing treatment and follow-up for AMD patients.
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Affiliation(s)
- Aya A Abd El-Khalek
- Communications and Electronics Engineering Department, Nile Higher Institute for Engineering and Technology, Mansoura, Egypt
| | - Hossam Magdy Balaha
- BioImaging Lab, Department of Bioengineering, J.B. Speed School of Engineering, University of Louisville, Louisville, KY, USA
| | - Norah Saleh Alghamdi
- Department of Computer Sciences, College of Computer and Information Sciences, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Mohammed Ghazal
- Electrical, Computer, and Biomedical Engineering Depatrment, Abu Dhabi University, Abu Dhabi, UAE
| | - Abeer T Khalil
- Communications and Electronics Engineering Department, Faculty of Engineering, Mansoura University, Mansoura, Egypt
| | - Mohy Eldin A Abo-Elsoud
- Communications and Electronics Engineering Department, Faculty of Engineering, Mansoura University, Mansoura, Egypt
| | - Ayman El-Baz
- BioImaging Lab, Department of Bioengineering, J.B. Speed School of Engineering, University of Louisville, Louisville, KY, USA.
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6
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Sasseville S, Karami S, Tchatchouang A, Charpentier P, Anney P, Gobert D, Proulx S. Biomaterials used for tissue engineering of barrier-forming cell monolayers in the eye. Front Bioeng Biotechnol 2023; 11:1269385. [PMID: 37840667 PMCID: PMC10569698 DOI: 10.3389/fbioe.2023.1269385] [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: 08/08/2023] [Accepted: 09/15/2023] [Indexed: 10/17/2023] Open
Abstract
Cell monolayers that form a barrier between two structures play an important role for the maintenance of tissue functionality. In the anterior portion of the eye, the corneal endothelium forms a barrier that controls fluid exchange between the aqueous humor of the anterior chamber and the corneal stroma. This monolayer is central in the pathogenesis of Fuchs endothelial corneal dystrophy (FECD). FECD is a common corneal disease, in which corneal endothelial cells deposit extracellular matrix that increases the thickness of its basal membrane (Descemet's membrane), and forms excrescences (guttae). With time, there is a decrease in endothelial cell density that generates vision loss. Transplantation of a monolayer of healthy corneal endothelial cells on a Descemet membrane substitute could become an interesting alternative for the treatment of this pathology. In the back of the eye, the retinal pigment epithelium (RPE) forms the blood-retinal barrier, controlling fluid exchange between the choriocapillaris and the photoreceptors of the outer retina. In the retinal disease dry age-related macular degeneration (dry AMD), deposits (drusen) form between the RPE and its basal membrane (Bruch's membrane). These deposits hinder fluid exchange, resulting in progressive RPE cell death, which in turn generates photoreceptor cell death, and vision loss. Transplantation of a RPE monolayer on a Bruch's membrane/choroidal stromal substitute to replace the RPE before photoreceptor cell death could become a treatment alternative for this eye disease. This review will present the different biomaterials that are proposed for the engineering of a monolayer of corneal endothelium for the treatment of FECD, and a RPE monolayer for the treatment of dry AMD.
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Affiliation(s)
- Samantha Sasseville
- Axe Médecine Régénératrice, Hôpital du Saint-Sacrement, Centre de Recherche en Organogénèse Expérimentale de l’Université Laval/LOEX; Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, QC, Canada
- Département d’ophtalmologie et d’oto-rhino-laryngologie-chirurgie cervico-faciale, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Samira Karami
- Axe Médecine Régénératrice, Hôpital du Saint-Sacrement, Centre de Recherche en Organogénèse Expérimentale de l’Université Laval/LOEX; Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, QC, Canada
- Département d’ophtalmologie et d’oto-rhino-laryngologie-chirurgie cervico-faciale, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Ange Tchatchouang
- Axe Médecine Régénératrice, Hôpital du Saint-Sacrement, Centre de Recherche en Organogénèse Expérimentale de l’Université Laval/LOEX; Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, QC, Canada
- Département d’ophtalmologie et d’oto-rhino-laryngologie-chirurgie cervico-faciale, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Pascale Charpentier
- Axe Médecine Régénératrice, Hôpital du Saint-Sacrement, Centre de Recherche en Organogénèse Expérimentale de l’Université Laval/LOEX; Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, QC, Canada
- Département d’ophtalmologie et d’oto-rhino-laryngologie-chirurgie cervico-faciale, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Princia Anney
- Axe Médecine Régénératrice, Hôpital du Saint-Sacrement, Centre de Recherche en Organogénèse Expérimentale de l’Université Laval/LOEX; Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, QC, Canada
- Département d’ophtalmologie et d’oto-rhino-laryngologie-chirurgie cervico-faciale, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Delphine Gobert
- Département d’ophtalmologie et d’oto-rhino-laryngologie-chirurgie cervico-faciale, Faculté de Médecine, Université Laval, Québec, QC, Canada
- Centre universitaire d’ophtalmologie (CUO), Hôpital du Saint-Sacrement, CHU de Québec-Université Laval, Québec, QC, Canada
| | - Stéphanie Proulx
- Axe Médecine Régénératrice, Hôpital du Saint-Sacrement, Centre de Recherche en Organogénèse Expérimentale de l’Université Laval/LOEX; Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, QC, Canada
- Département d’ophtalmologie et d’oto-rhino-laryngologie-chirurgie cervico-faciale, Faculté de Médecine, Université Laval, Québec, QC, Canada
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Shen G, Li Y, Zeng Y, Hong F, Zhang J, Wang Y, Zhang C, Xiang W, Wang J, Fang Z, Qi W, Yang X, Gao G, Zhou T. Kallistatin Deficiency Induces the Oxidative Stress-Related Epithelial-Mesenchymal Transition of Retinal Pigment Epithelial Cells: A Novel Protagonist in Age-Related Macular Degeneration. Invest Ophthalmol Vis Sci 2023; 64:15. [PMID: 37682567 PMCID: PMC10500364 DOI: 10.1167/iovs.64.12.15] [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: 04/03/2023] [Accepted: 08/15/2023] [Indexed: 09/09/2023] Open
Abstract
Purpose Retinal pigment epithelium (RPE) dysfunction induced by oxidative stress-related epithelial-mesenchymal transition (EMT) of RPE is the primary underlying mechanism of age-related macular degeneration (AMD). Kallistatin (KAL) is a secreted protein with an antioxidative stress effect. However, the relationship between KAL and EMT in RPE has not been determined. Therefore we aimed to explore the impact and mechanism of KAL in oxidative stress-induced EMT of RPE. Methods Sodium iodate (SI) was injected intraperitoneally to construct the AMD rat model and investigate the changes in RPE morphology and KAL expression. KAL knockout rats and KAL transgenic mice were used to explain the effects of KAL on EMT and oxidative stress. In addition, Snail overexpressed adenovirus and si-RNA transfected ARPE19 cells to verify the involvement of Snail in mediating KAL-suppressed EMT of RPE. Results AMD rats induced by SI expressed less KAL in the retina, and KAL knockout rats showed RPE dysfunction spontaneously where EMT and reactive oxygen species (ROS) production increased in RPE. In contrast, KAL overexpression attenuated EMT and ROS levels in RPE, even in TGF-β treatment. Mechanistically, Snail reversed the beneficial effect of KAL on EMT and ROS reduction. Moreover, KAL ameliorated SI-induced AMD-like pathological changes. Conclusions Our findings demonstrated that KAL inhibits oxidative stress-induced EMT by downregulating the transcription factor Snail. Herein, KAL knockout rats may be an appropriate animal model for observing spontaneous RPE dysfunction for AMD-like retinopathy, and KAL may represent a novel therapeutic target for treating dry AMD.
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Affiliation(s)
- Gang Shen
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
- Department of Laboratory Medicine, Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Yanmei Li
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Yongcheng Zeng
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Fuyan Hong
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Jing Zhang
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Yan Wang
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Chengwei Zhang
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Wei Xiang
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Jinhong Wang
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Zhenzhen Fang
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Weiwei Qi
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Xia Yang
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
- Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Guoquan Gao
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
- Guangdong Engineering & Technology Research Center for Gene Manipulation and Biomacromolecular Products, Sun Yat-Sen University, Guangzhou, China
| | - Ti Zhou
- Department of Biochemistry and Molecular Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
- Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
- China Key Laboratory of Tropical Disease Control (Sun Yat-Sen University), Ministry of Education, Guangzhou, China
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8
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Lenin RR, Koh YH, Zhang Z, Yeo YZ, Parikh BH, Seah I, Wong W, Su X. Dysfunctional Autophagy, Proteostasis, and Mitochondria as a Prelude to Age-Related Macular Degeneration. Int J Mol Sci 2023; 24:ijms24108763. [PMID: 37240109 DOI: 10.3390/ijms24108763] [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: 12/29/2022] [Revised: 05/05/2023] [Accepted: 05/06/2023] [Indexed: 05/28/2023] Open
Abstract
Retinal pigment epithelial (RPE) cell dysfunction is a key driving force of AMD. RPE cells form a metabolic interface between photoreceptors and choriocapillaris, performing essential functions for retinal homeostasis. Through their multiple functions, RPE cells are constantly exposed to oxidative stress, which leads to the accumulation of damaged proteins, lipids, nucleic acids, and cellular organelles, including mitochondria. As miniature chemical engines of the cell, self-replicating mitochondria are heavily implicated in the aging process through a variety of mechanisms. In the eye, mitochondrial dysfunction is strongly associated with several diseases, including age-related macular degeneration (AMD), which is a leading cause of irreversible vision loss in millions of people globally. Aged mitochondria exhibit decreased rates of oxidative phosphorylation, increased reactive oxygen species (ROS) generation, and increased numbers of mitochondrial DNA mutations. Mitochondrial bioenergetics and autophagy decline during aging because of insufficient free radical scavenger systems, the impairment of DNA repair mechanisms, and reductions in mitochondrial turnover. Recent research has uncovered a much more complex role of mitochondrial function and cytosolic protein translation and proteostasis in AMD pathogenesis. The coupling of autophagy and mitochondrial apoptosis modulates the proteostasis and aging processes. This review aims to summarise and provide a perspective on (i) the current evidence of autophagy, proteostasis, and mitochondrial dysfunction in dry AMD; (ii) current in vitro and in vivo disease models relevant to assessing mitochondrial dysfunction in AMD, and their utility in drug screening; and (iii) ongoing clinical trials targeting mitochondrial dysfunction for AMD therapeutics.
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Affiliation(s)
- Raji Rajesh Lenin
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), 1E Kent Ridge Road, NUHS Tower Block Level 7, Singapore 119228, Singapore
- Department of Medical Research, SRM Institute of Science and Technology, Kattankulathur 603203, Tamil Nadu, India
| | - Yi Hui Koh
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), 1E Kent Ridge Road, NUHS Tower Block Level 7, Singapore 119228, Singapore
| | - Zheting Zhang
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), 1E Kent Ridge Road, NUHS Tower Block Level 7, Singapore 119228, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University (NTU), 11 Mandalay Road, Experimental Medicine Building, Singapore 308232, Singapore
| | - Yan Zhuang Yeo
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology, and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore
| | - Bhav Harshad Parikh
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology, and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore
| | - Ivan Seah
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), 1E Kent Ridge Road, NUHS Tower Block Level 7, Singapore 119228, Singapore
| | - Wendy Wong
- Department of Ophthalmology, National University Hospital (NUH), 1E Kent Ridge Road, NUHS Tower Block Level 7, Singapore 119228, Singapore
| | - Xinyi Su
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), 1E Kent Ridge Road, NUHS Tower Block Level 7, Singapore 119228, Singapore
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology, and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore
- Department of Ophthalmology, National University Hospital (NUH), 1E Kent Ridge Road, NUHS Tower Block Level 7, Singapore 119228, Singapore
- Singapore Eye Research Institute (SERI), The Academia, 20 College Road, Level 6 Discovery Tower, Singapore 169856, Singapore
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9
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Wooff Y, Cioanca AV, Wills E, Chu-Tan JA, Sekar R, Natoli R. Short exposure to photo-oxidative damage triggers molecular signals indicative of early retinal degeneration. Front Immunol 2023; 14:1088654. [PMID: 37180103 PMCID: PMC10174249 DOI: 10.3389/fimmu.2023.1088654] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 04/12/2023] [Indexed: 05/15/2023] Open
Abstract
Introduction Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world, currently affecting over 350 billion people globally. For the most prevalent late-stage form of this disease, atrophic AMD, there are no available prevention strategies or treatments, in part due to inherent difficulties in early-stage diagnosis. Photo-oxidative damage is a well-established model for studying inflammatory and cell death features that occur in late-stage atrophic AMD, however to date has not been investigated as a potential model for studying early features of disease onset. Therefore, in this study we aimed to determine if short exposure to photo-oxidative damage could be used to induce early retinal molecular changes and advance this as a potential model for studying early-stage AMD. Methods C57BL/6J mice were exposed to 1, 3, 6, 12, or 24h photo-oxidative damage (PD) using 100k lux bright white light. Mice were compared to dim-reared (DR) healthy controls as well as mice which had undergone long periods of photo-oxidative damage (3d and 5d-PD) as known timepoints for inducing late-stage retinal degeneration pathologies. Cell death and retinal inflammation were measured using immunohistochemistry and qRT-PCR. To identify retinal molecular changes, retinal lysates were sent for RNA sequencing, following which bioinformatics analyses including differential expression and pathway analyses were performed. Finally, to investigate modulations in gene regulation as a consequence of degeneration, microRNA (miRNA) expression patterns were quantified using qRT-PCR and visualized using in situ hybridization. Results Short exposure to photo-oxidative damage (1-24h-PD) induced early molecular changes in the retina, with progressive downregulation of homeostatic pathways including metabolism, transport and phototransduction observed across this time-course. Inflammatory pathway upregulation was observed from 3h-PD, preceding observable levels of microglia/macrophage activation which was noted from 6h-PD, as well as significant photoreceptor row loss from 24h-PD. Further rapid and dynamic movement of inflammatory regulator miRNA, miR-124-3p and miR-155-5p, was visualized in the retina in response to degeneration. Conclusion These results support the use of short exposure to photo-oxidative damage as a model of early AMD and suggest that early inflammatory changes in the retina may contribute to pathological features of AMD progression including immune cell activation and photoreceptor cell death. We suggest that early intervention of these inflammatory pathways by targeting miRNA such as miR-124-3p and miR-155-5p or their target genes may prevent progression into late-stage pathology.
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Affiliation(s)
- Yvette Wooff
- Clear Vision Research Group, Eccles Institute of Neuroscience, John Curtin School of Medical Research, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
- School of Medicine and Psychology, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
| | - Adrian V. Cioanca
- Clear Vision Research Group, Eccles Institute of Neuroscience, John Curtin School of Medical Research, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
- School of Medicine and Psychology, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
| | - Elly Wills
- Clear Vision Research Group, Eccles Institute of Neuroscience, John Curtin School of Medical Research, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
- School of Medicine and Psychology, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
| | - Joshua A. Chu-Tan
- Clear Vision Research Group, Eccles Institute of Neuroscience, John Curtin School of Medical Research, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
- School of Medicine and Psychology, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
| | - Rakshanya Sekar
- Clear Vision Research Group, Eccles Institute of Neuroscience, John Curtin School of Medical Research, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
- School of Medicine and Psychology, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
| | - Riccardo Natoli
- Clear Vision Research Group, Eccles Institute of Neuroscience, John Curtin School of Medical Research, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
- School of Medicine and Psychology, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
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10
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A laser-induced mouse model of progressive retinal degeneration with central sparing displays features of parafoveal geographic atrophy. Sci Rep 2023; 13:4194. [PMID: 36918701 PMCID: PMC10014848 DOI: 10.1038/s41598-023-31392-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 03/10/2023] [Indexed: 03/16/2023] Open
Abstract
There are no disease-modifying treatments available for geographic atrophy (GA), the advanced form of dry age-related macular degeneration. Current murine models fail to fully recapitulate the features of GA and thus hinder drug discovery. Here we describe a novel mouse model of retinal degeneration with hallmark features of GA. We used an 810 nm laser to create a retinal lesion with central sparing (RLCS), simulating parafoveal atrophy observed in patients with progressive GA. Laser-induced RLCS resulted in progressive GA-like pathology with the development of a confluent atrophic lesion. We demonstrate significant changes to the retinal structure and thickness in the central unaffected retina over a 24-week post-laser period, confirmed by longitudinal optical coherence tomography scans. We further show characteristic features of progressive GA, including a gradual reduction in the thickness of the central, unaffected retina and of total retinal thickness. Histological changes observed in the RLCS correspond to GA pathology, which includes the collapse of the outer nuclear layer, increased numbers of GFAP + , CD11b + and FcγRI + cells, and damage to cone and rod photoreceptors. We demonstrate a laser-induced mouse model of parafoveal GA progression, starting at 2 weeks post-laser and reaching confluence at 24 weeks post-laser. This 24-week time-frame in which GA pathology develops, provides an extended window of opportunity for proof-of-concept evaluation of drugs targeting GA. This time period is an added advantage compared to several existing models of geographic atrophy.
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11
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Recent Advances in Proteomics-Based Approaches to Studying Age-Related Macular Degeneration: A Systematic Review. Int J Mol Sci 2022; 23:ijms232314759. [PMID: 36499086 PMCID: PMC9735888 DOI: 10.3390/ijms232314759] [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: 10/06/2022] [Revised: 11/17/2022] [Accepted: 11/22/2022] [Indexed: 11/29/2022] Open
Abstract
Age-related macular degeneration (AMD) is a common ocular disease characterized by degeneration of the central area of the retina in the elderly population. Progression and response to treatment are influenced by genetic and non-genetic factors. Proteomics is a powerful tool to study, at the molecular level, the mechanisms underlying the progression of the disease, to identify new therapeutic targets and to establish biomarkers to monitor progression and treatment effectiveness. In this work, we systematically review the use of proteomics-based approaches for the study of the molecular mechanisms underlying the development of AMD, as well as the progression of the disease and on-treatment patient monitoring. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) reporting guidelines were followed. Proteomic approaches have identified key players in the onset of the disease, such as complement components and proteins involved in lipid metabolism and oxidative stress, but also in the progression to advanced stages, including factors related to extracellular matrix integrity and angiogenesis. Although anti-vascular endothelial growth factor (anti-VEGF)-based therapy has been crucial in the treatment of neovascular AMD, it is necessary to deepen our understanding of the underlying disease mechanisms to move forward to next-generation therapies for later-stage forms of this multifactorial disease.
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12
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Patel PN, Patel PA, Land MR, Bakerkhatib-Taha I, Ahmed H, Sheth V. Targeting the Complement Cascade for Treatment of Dry Age-Related Macular Degeneration. Biomedicines 2022; 10:1884. [PMID: 36009430 PMCID: PMC9405256 DOI: 10.3390/biomedicines10081884] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/28/2022] [Accepted: 08/01/2022] [Indexed: 11/16/2022] Open
Abstract
Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss in the elderly population. AMD is characterized in its late form by neovascularization (wet type) or geographic atrophy of the retinal pigment epithelium cell layer (dry type). Regarding the latter type, there is growing evidence supporting an association between the pathophysiology of dry AMD and key proteins in the complement cascade. The complement cascade works as a central part of the innate immune system by defending against foreign pathogens and modified self-tissues. Through three distinct pathways, a series of plasma and membrane-associated serum proteins are activated upon identification of a foreign entity. Several of these proteins have been implicated in the development and progression of dry AMD. Potential therapeutic targets include C1q, C3, C5, complement factors (B, D, H, I), membrane attack complex, and properdin. In this review, we provide an understanding of the role of the complement system in dry AMD and discuss the emerging therapies in early phase clinical trials. The tentative hope is that these drugs may offer the potential to intervene at earlier stages in dry AMD pathogenesis, thereby preventing progression to late disease.
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Affiliation(s)
- Prem N. Patel
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Parth A. Patel
- Department of Ophthalmology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Matthew R. Land
- Department of Ophthalmology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | | | - Harris Ahmed
- Department of Ophthalmology, Loma Linda University Medical Center, Loma Linda, CA 92350, USA
| | - Veeral Sheth
- University Retina and Macula Associates, Oak Forest, IL 60452, USA
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13
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Henning Y, Blind US, Larafa S, Matschke J, Fandrey J. Hypoxia aggravates ferroptosis in RPE cells by promoting the Fenton reaction. Cell Death Dis 2022; 13:662. [PMID: 35906211 PMCID: PMC9338085 DOI: 10.1038/s41419-022-05121-z] [Citation(s) in RCA: 55] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 07/15/2022] [Accepted: 07/20/2022] [Indexed: 01/21/2023]
Abstract
Oxidative stress and hypoxia in the retinal pigment epithelium (RPE) have long been considered major risk factors in the pathophysiology of age-related macular degeneration (AMD), but systematic investigation of the interplay between these two risk factors was lacking. For this purpose, we treated a human RPE cell line (ARPE-19) with sodium iodate (SI), an oxidative stress agent, together with dimethyloxalylglycine (DMOG) which leads to stabilization of hypoxia-inducible factors (HIFs), key regulators of cellular adaptation to hypoxic conditions. We found that HIF stabilization aggravated oxidative stress-induced cell death by SI and iron-dependent ferroptosis was identified as the main cell death mechanism. Ferroptotic cell death depends on the Fenton reaction where H2O2 and iron react to generate hydroxyl radicals which trigger lipid peroxidation. Our findings clearly provide evidence for superoxide dismutase (SOD) driven H2O2 production fostering the Fenton reaction as indicated by triggered SOD activity upon DMOG + SI treatment as well as by reduced cell death levels upon SOD2 knockdown. In addition, iron transporters involved in non-transferrin-bound Fe2+ import as well as intracellular iron levels were also upregulated. Consequently, chelation of Fe2+ by 2'2-Bipyridyl completely rescued cells. Taken together, we show for the first time that HIF stabilization under oxidative stress conditions aggravates ferroptotic cell death in RPE cells. Thus, our study provides a novel link between hypoxia, oxidative stress and iron metabolism in AMD pathophysiology. Since iron accumulation and altered iron metabolism are characteristic features of AMD retinas and RPE cells, our cell culture model is suitable for high-throughput screening of new treatment approaches against AMD.
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Affiliation(s)
- Yoshiyuki Henning
- grid.410718.b0000 0001 0262 7331Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Ursula Sarah Blind
- grid.410718.b0000 0001 0262 7331Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Safa Larafa
- grid.410718.b0000 0001 0262 7331Institute of Cell Biology (Cancer Research), University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Johann Matschke
- grid.410718.b0000 0001 0262 7331Institute of Cell Biology (Cancer Research), University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Joachim Fandrey
- grid.410718.b0000 0001 0262 7331Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
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14
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Bhattacharyya A. The detrimental effects of progression of retinal degeneration in the visual cortex. Front Cell Neurosci 2022; 16:904175. [PMID: 35966197 PMCID: PMC9372284 DOI: 10.3389/fncel.2022.904175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 07/04/2022] [Indexed: 11/13/2022] Open
Abstract
The leading cause of blindness in inherited and age-related retinal degeneration (RD) is the death of retinal photoreceptors such as rods and cones. The most prevalent form of RD is age-related macular degeneration (AMD) which affects the macula resulting in an irreversible loss of vision. The other is a heterogenous group of inherited disorders known as Retinitis Pigmentosa (RP) caused by the progressive loss of photoreceptors. Several approaches have been developed in recent years to artificially stimulate the remaining retinal neurons using optogenetics, retinal prostheses, and chemical photoswitches. However, the outcome of these strategies has been limited. The success of these treatments relies on the morphology, physiology, and proper functioning of the remaining intact structures in the downstream visual pathway. It is not completely understood what all alterations occur in the visual cortex during RD. In this review, I will discuss the known information in the literature about morphological and functional changes that occur in the visual cortex in rodents and humans during RD. The aim is to highlight the changes in the visual cortex that will be helpful for developing tools and strategies directed toward the restoration of high-resolution vision in patients with visual impairment.
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15
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Molins B, Mesquida M, Adan A. Bioengineering approaches for modelling retinal pathologies of the outer blood-retinal barrier. Prog Retin Eye Res 2022:101097. [PMID: 35840488 DOI: 10.1016/j.preteyeres.2022.101097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 05/31/2022] [Accepted: 06/29/2022] [Indexed: 11/18/2022]
Abstract
Alterations of the junctional complex of the outer blood-retinal barrier (oBRB), which is integrated by the close interaction of the retinal pigment epithelium, the Bruch's membrane, and the choriocapillaris, contribute to the loss of neuronal signalling and subsequent vision impairment in several retinal inflammatory disorders such as age-related macular degeneration and diabetic retinopathy. Reductionist approaches into the mechanisms that underlie such diseases have been hindered by the absence of adequate in vitro models using human cells to provide the 3D dynamic architecture that enables expression of the in vivo phenotype of the oBRB. Conventional in vitro cell models are based on 2D monolayer cellular cultures, unable to properly recapitulate the complexity of living systems. The main drawbacks of conventional oBRB models also emerge from the cell sourcing, the lack of an appropriate Bruch's membrane analogue, and the lack of choroidal microvasculature with flow. In the last years, the advent of organ-on-a-chip, bioengineering, and stem cell technologies is providing more advanced 3D models with flow, multicellularity, and external control over microenvironmental properties. By incorporating additional biological complexity, organ-on-a-chip devices can mirror physiologically relevant properties of the native tissue while offering additional set ups to model and study disease. In this review we first examine the current understanding of oBRB biology as a functional unit, highlighting the coordinated contribution of the different components to barrier function in health and disease. Then we describe recent advances in the use of pluripotent stem cells-derived retinal cells, Bruch's membrane analogues, and co-culture techniques to recapitulate the oBRB. We finally discuss current advances and challenges of oBRB-on-a-chip technologies for disease modelling.
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Affiliation(s)
- Blanca Molins
- Group of Ocular Inflammation: Clinical and Experimental Studies, Institut d'Investigacions Biomèdiques Agustí Pi I Sunyer (IDIBAPS), C/ Sabino de Arana 1, 08028, Barcelona, Spain.
| | - Marina Mesquida
- Group of Ocular Inflammation: Clinical and Experimental Studies, Institut d'Investigacions Biomèdiques Agustí Pi I Sunyer (IDIBAPS), C/ Sabino de Arana 1, 08028, Barcelona, Spain; Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Alfredo Adan
- Group of Ocular Inflammation: Clinical and Experimental Studies, Institut d'Investigacions Biomèdiques Agustí Pi I Sunyer (IDIBAPS), C/ Sabino de Arana 1, 08028, Barcelona, Spain; Instituto Clínic de Oftalmología, Hospital Clínic Barcelona, C/ Sabino de Arana 1, 08028, Barcelona, Spain
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16
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Neuroprotection for Age-Related Macular Degeneration. OPHTHALMOLOGY SCIENCE 2022; 2:100192. [PMID: 36570623 PMCID: PMC9767822 DOI: 10.1016/j.xops.2022.100192] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 06/24/2022] [Accepted: 06/28/2022] [Indexed: 12/27/2022]
Abstract
Age-related macular degeneration (AMD) is a leading cause of blindness worldwide. Early to intermediate AMD is characterized by the accumulation of lipid- and protein-rich drusen. Late stages of the disease are characterized by the development of choroidal neovascularization, termed "exudative" or "neovascular AMD," or retinal pigment epithelium (RPE) cell and photoreceptor death, termed "geographic atrophy" (GA) in advanced nonexudative AMD. Although we have effective treatments for exudative AMD in the form of anti-VEGF agents, they have no role for patients with GA. Neuroprotection strategies have emerged as a possible way to slow photoreceptor degeneration and vision loss in patients with GA. These approaches include reduction of oxidative stress, modulation of the visual cycle, reduction of toxic molecules, inhibition of pathologic protein activity, prevention of cellular apoptosis or programmed necrosis (necroptosis), inhibition of inflammation, direct activation of neurotrophic factors, delivery of umbilical tissue-derived cells, and RPE replacement. Despite active investigation in this area and significant promise based on preclinical studies, many clinical studies have not yielded successful results. We discuss selected past and current neuroprotection trials for AMD, highlight the lessons learned from these past studies, and discuss our perspective regarding remaining questions that must be answered before neuroprotection can be successfully applied in the field of AMD research.
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Key Words
- AD, Alzheimer disease
- ALA, alpha lipoic acid
- AMD, age-related macular degeneration
- AREDS, Age-Related Eye Disease Study
- AREDS2, Age-Related Eye Disease Study 2
- Age-related macular degeneration
- CFH, complement factor H
- CNTF, ciliary neurotrophic factor
- GA, geographic atrophy
- HTRA1, high-temperature requirement A1
- IOP, intraocular pressure
- Neuroprotection
- RBP, retinol-binding protein
- RGC, retinal ganglion cell
- RIPK3, receptor-interacting serine/threonine-protein kinase 3
- ROS, reactive oxygen species
- RPE, retinal pigment epithelium
- Retinal degeneration
- VA, visual acuity
- iPSC, induced pluripotent stem cell
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Koster C, van den Hurk KT, ten Brink JB, Lewallen CF, Stanzel BV, Bharti K, Bergen AA. Sodium-Iodate Injection Can Replicate Retinal Degenerative Disease Stages in Pigmented Mice and Rats: Non-Invasive Follow-Up Using OCT and ERG. Int J Mol Sci 2022; 23:ijms23062918. [PMID: 35328338 PMCID: PMC8953416 DOI: 10.3390/ijms23062918] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 03/01/2022] [Accepted: 03/04/2022] [Indexed: 11/16/2022] Open
Abstract
Purpose: The lack of suitable animal models for (dry) age-related macular degeneration (AMD) has hampered therapeutic research into the disease, so far. In this study, pigmented rats and mice were systematically injected with various doses of sodium iodate (SI). After injection, the retinal structure and visual function were non-invasively characterized over time to obtain in-depth data on the suitability of these models for studying experimental therapies for retinal degenerative diseases, such as dry AMD. Methods: SI was injected into the tail vein (i.v.) using a series of doses (0–70 mg/kg) in adolescent C57BL/6J mice and Brown Norway rats. The retinal structure and function were assessed non-invasively at baseline (day 1) and at several time points (1–3, 5, and 10-weeks) post-injection by scanning laser ophthalmoscopy (SLO), optical coherence tomography (OCT), and electroretinography (ERG). Results: After the SI injection, retinal degeneration in mice and rats yielded similar results. The lowest dose (10 mg/kg) resulted in non-detectable structural or functional effects. An injection with 20 mg/kg SI did not result in an evident retinal degeneration as judged from the OCT data. In contrast, the ERG responses were temporarily decreased but returned to baseline within two-weeks. Higher doses (30, 40, 50, and 70 mg/kg) resulted in moderate to severe structural RPE and retinal injury and decreased the ERG amplitudes, indicating visual impairment in both mice and rat strains. Conclusions: After the SI injections, we observed dose-dependent structural and functional pathological effects on the retinal pigment epithelium (RPE) and retina in the pigmented mouse and rat strains that were used in this study. Similar effects were observed in both species. In particular, a dose of 30 mg/kg seems to be suitable for future studies on developing experimental therapies. These relatively easily induced non-inherited models may serve as useful tools for evaluating novel therapies for RPE-related retinal degenerations, such as AMD.
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Affiliation(s)
- Céline Koster
- Department of Human Genetics, Section Ophthalmogenetics, Amsterdam University Medical Centers (AUMC), University of Amsterdam (UvA), Location AMC, Meibergdreef, 1105 AZ Amsterdam, The Netherlands; (C.K.); (K.T.v.d.H.); (J.B.t.B.)
| | - Koen T. van den Hurk
- Department of Human Genetics, Section Ophthalmogenetics, Amsterdam University Medical Centers (AUMC), University of Amsterdam (UvA), Location AMC, Meibergdreef, 1105 AZ Amsterdam, The Netherlands; (C.K.); (K.T.v.d.H.); (J.B.t.B.)
| | - Jacoline B. ten Brink
- Department of Human Genetics, Section Ophthalmogenetics, Amsterdam University Medical Centers (AUMC), University of Amsterdam (UvA), Location AMC, Meibergdreef, 1105 AZ Amsterdam, The Netherlands; (C.K.); (K.T.v.d.H.); (J.B.t.B.)
| | - Colby F. Lewallen
- Georgia Institute of Technology, G.W. Woodruff School of Mechanical Engineering, Atlanta, GA 30332, USA;
| | - Boris V. Stanzel
- Eye Clinic Sulzbach, Knappschaft Hospital Saar, 66280 Sulzbach/Saar, Germany;
- Department of Ophthalmology, University of Bonn, 53113 Bonn, Germany
| | - Kapil Bharti
- Ocular and Stem Cell Research Section, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA;
| | - Arthur A. Bergen
- Department of Human Genetics, Section Ophthalmogenetics, Amsterdam University Medical Centers (AUMC), University of Amsterdam (UvA), Location AMC, Meibergdreef, 1105 AZ Amsterdam, The Netherlands; (C.K.); (K.T.v.d.H.); (J.B.t.B.)
- Department of Ophthalmology, AUMC, UvA, Location AMC, Meibergdreef, 1105 AZ Amsterdam, The Netherlands
- Correspondence:
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18
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Pankova N, Baek DSH, Zhao X, Wang H, Reyad MM, Liang H, Joshi R, Boyd SR. Evolving Patterns of Hyperfluorescent Fundus Autofluorescence Accompany Retinal Atrophy in the Rat and Mimic Atrophic Age-Related Macular Degeneration. Transl Vis Sci Technol 2022; 11:3. [PMID: 35254423 PMCID: PMC8914569 DOI: 10.1167/tvst.11.3.3] [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] [Indexed: 11/24/2022] Open
Abstract
Purpose Complex two-dimensional (2D) patterns of hyperfluorescent short-wave fundus autofluorescence (FAF) at the border of geographic atrophy (GA) can predict its expansion in patients with late non-exudative “dry” AMD. However, preclinical models do not phenocopy this important feature of disease. We sought to describe the spatiotemporal changes in hyperfluorescent FAF patterns that occur following acute oxidative stress, potentially in association with GA expansion. Methods Sprague Dawley rats (n = 54) received systemic sodium iodate (25–45 mg/kg, n = 90 eyes) or saline (n = 18 eyes) and underwent serial full fundus imaging by confocal scanning laser ophthalmoscopy, including blue FAF and delayed near-infrared analysis. Composite images of the fundus were assembled, and the 2D patterns were described qualitatively and quantitatively. A subset of eyes underwent tissue analysis, and four underwent optical coherence tomography (OCT) imaging. Results Reproducibly changing, complex patterns of hyperfluorescent FAF emerge at the borders of toxin-induced damage; however, in the absence of GA expansion, they percolate inward within the region of retinal pigment epithelium loss, evolving, maturing, and senescing in situ over time. Unexpectedly, the late FAF patterns most closely resemble the diffuse tricking form of clinical disease. A five-stage classification system is presented. Conclusions Longitudinal, full-fundus imaging of outer retinal atrophy in the rat eye identifies evolving, complex patterns of hyperfluorescent FAF that phenocopy aspects of disease. Translational Relevance This work provides a novel tool to assess hyperfluorescent FAF in association with progressive retinal atrophy, a therapeutic target in late AMD.
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Affiliation(s)
- Natalie Pankova
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - David Sung Hyeon Baek
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Xu Zhao
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Hai Wang
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Matthew-Mina Reyad
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Huiyuan Liang
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Rahul Joshi
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Shelley Romayne Boyd
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada.,Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
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19
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Shen G, Li Y, Hong F, Zhang J, Fang Z, Xiang W, Qi W, Yang X, Gao G, Zhou T. A role for Snail-MnSOD axis in regulating epithelial-to-mesenchymal transition markers expression in RPE cells. Biochem Biophys Res Commun 2021; 585:146-154. [PMID: 34808498 DOI: 10.1016/j.bbrc.2021.11.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 11/10/2021] [Indexed: 12/16/2022]
Abstract
Age-related macular degeneration (AMD) is a common cause of vision loss. The epithelial-mesenchymal transition (EMT) of retinal pigment epithelial (RPE) cells, accompanied by oxidative damage, plays a crucial role in AMD. It is well known that manganese superoxide dismutase (MnSOD) encoded by SOD2 is a critical molecule in fighting against oxidative stress, and Snail encoded by SNAI1 is the essential transcription factor for EMT. However, the effect of MnSOD on EMT and the underlying mechanism in RPE cells remains unknown. In this study, we found that MnSOD knockdown triggered the EMT by upregulating Snail, while MnSOD overexpression reversed EMT even with TGFβ treatment in RPE cells, and the anti-oxidative stress activity of MnSOD mediated this observation. In addition, Snail depletion increased both expression and activity of MnSOD while Snail overexpression decreased MnSOD expression and activity, and Dual-luciferase reporter and ChIP assays showed that Snail directly bound to E-box (CACCTG) in the SOD2 promoter. Moreover, MnSOD over-expression and Snail interference co-treatment strengthened the anti-oxidation and EMT reversing. Therefore, our findings demonstrate that MnSOD prevents EMT of RPE cells in AMD through inhibiting oxidative injury to RPE. Moreover, a critical EMT transcription factor, Snail, functions as a new negative transcriptional factor of SOD2. Herein, the Snail-MnSOD axis forms a mutual loop in the development of AMD, which may be a novel systemic treatment target for preventing AMD.
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Affiliation(s)
- Gang Shen
- Program of Molecular Medicine, Affiliated Guangzhou Women and Children's Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China; Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Department of Laboratory Medicine, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Yanmei Li
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Fuyan Hong
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Jing Zhang
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Zhenzhen Fang
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Wei Xiang
- Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Weiwei Qi
- Program of Molecular Medicine, Affiliated Guangzhou Women and Children's Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China; Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Xia Yang
- Program of Molecular Medicine, Affiliated Guangzhou Women and Children's Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China; Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Guoquan Gao
- Program of Molecular Medicine, Affiliated Guangzhou Women and Children's Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China; Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Guangdong Engineering & Technology Research Center for Gene Manipulation and Biomacromolecular Products, Sun Yat-sen University, Guangzhou, China
| | - Ti Zhou
- Program of Molecular Medicine, Affiliated Guangzhou Women and Children's Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China; Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; China Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Ministry of Education, Guangzhou, China.
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20
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Villarejo-Zori B, Jiménez-Loygorri JI, Zapata-Muñoz J, Bell K, Boya P. New insights into the role of autophagy in retinal and eye diseases. Mol Aspects Med 2021; 82:101038. [PMID: 34620506 DOI: 10.1016/j.mam.2021.101038] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 09/12/2021] [Accepted: 09/27/2021] [Indexed: 02/06/2023]
Abstract
Autophagy is a fundamental homeostatic pathway that mediates the degradation and recycling of intracellular components. It serves as a key quality control mechanism, especially in non-dividing cells such as neurons. Proteins, lipids, and even whole organelles are engulfed in autophagosomes and delivered to the lysosome for elimination. The retina is a light-sensitive tissue located in the back of the eye that detects and processes visual images. Vision is a highly demanding process, making the eye one of the most metabolically active tissues in the body and photoreceptors display glycolytic metabolism, even in the presence of oxygen. The retina and eye are also exposed to other stressors that can impair their function, including genetic mutations and age-associated changes. Autophagy, among other pathways, is therefore a key process for the preservation of retinal homeostasis. Here, we review the roles of both canonical and non-canonical autophagy in normal retinal function. We discuss the most recent studies investigating the participation of autophagy in eye diseases such as age-related macular degeneration, glaucoma, and diabetic retinopathy and its role protecting photoreceptors in several forms of retinal degeneration. Finally, we consider the therapeutic potential of strategies that target autophagy pathways to treat prevalent retinal and eye diseases.
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Affiliation(s)
- Beatriz Villarejo-Zori
- Department of Cellular and Molecular Biology, Margarita Salas Center for Biological Research, CSIC, Ramiro de Maetzu, 9, 28040, Madrid, Spain
| | - Juan Ignacio Jiménez-Loygorri
- Department of Cellular and Molecular Biology, Margarita Salas Center for Biological Research, CSIC, Ramiro de Maetzu, 9, 28040, Madrid, Spain
| | - Juan Zapata-Muñoz
- Department of Cellular and Molecular Biology, Margarita Salas Center for Biological Research, CSIC, Ramiro de Maetzu, 9, 28040, Madrid, Spain
| | - Katharina Bell
- Singapore Eye Research Institute, Singapore National Eye Centre, Republic of Singapore
| | - Patricia Boya
- Department of Cellular and Molecular Biology, Margarita Salas Center for Biological Research, CSIC, Ramiro de Maetzu, 9, 28040, Madrid, Spain.
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21
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HK2 Mediated Glycolytic Metabolism in Mouse Photoreceptors Is Not Required to Cause Late Stage Age-Related Macular Degeneration-Like Pathologies. Biomolecules 2021; 11:biom11060871. [PMID: 34208233 PMCID: PMC8230848 DOI: 10.3390/biom11060871] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/01/2021] [Accepted: 06/09/2021] [Indexed: 12/12/2022] Open
Abstract
Age-related macular degeneration (AMD) is a multifactorial disease of unclear etiology. We previously proposed that metabolic adaptations in photoreceptors (PRs) play a role in disease progression. We mimicked these metabolic adaptations in mouse PRs through deletion of the tuberous sclerosis complex (TSC) protein TSC1. Here, we confirm our previous findings by deletion of the other complex protein, namely TSC2, in rod photoreceptors. Similar to deletion of Tsc1, mice with deletion of Tsc2 in rods develop AMD-like pathologies, including accumulation of apolipoproteins, migration of microglia, geographic atrophy, and neovascular pathologies. Subtle differences between the two mouse models, such as a significant increase in microglia activation with loss of Tsc2, were seen as well. To investigate the role of altered glucose metabolism in disease pathogenesis, we generated mice with simulation deletions of Tsc2 and hexokinase-2 (Hk2) in rods. Although retinal lactate levels returned to normal in mice with Tsc2-Hk2 deletion, AMD-like pathologies still developed. The data suggest that the metabolic adaptations in PRs that cause AMD-like pathologies are independent of HK2-mediated aerobic glycolysis.
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22
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Abstract
PURPOSE OF REVIEW This review explores metabolic syndrome (MetS) as a risk factor that accelerates aging in retinal neurons and may contribute to the neurodegeneration seen in glaucomatous optic neuropathy (GON) and age-related macular degeneration (AMD). RECENT FINDINGS Both animal model experiments and epidemiologic studies suggest that metabolic stress may lead to aberrant regulation of a number of cellular pathways that ultimately lead to premature aging of the cell, including those of a neuronal lineage. SUMMARY GON and AMD are each leading causes of irreversible blindness worldwide. Aging is a significant risk factor in the specific retinal neuron loss that is seen with each condition. Though aging at a cellular level is difficult to define, there are many mechanistic modifiers of aging. Metabolic-related stresses induce inflammation, oxidative stress, mitochondrial dysfunction, endoplasmic reticulum stress, alterations to the unfolded protein response, defects in autophagy, alterations to the microbiome, and deposition of advanced glycation end products that can all hasten the aging process. Due to the number of variables related to metabolic health, defining criteria to enable the study of risk factors at a population level is challenging. MetS is a definable constellation of related metabolic risk factors that includes enlarged waist circumference, dyslipidemia, systemic hypertension, and hyperglycemia. MetS has been associated with both GON and AMD and may contribute to disease onset and/or progression in each disease.
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