1
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Hu Y, Ge K, Du Y. Paeoniflorin alleviates TGF-β2-mediated extracellular matrix remodeling and oxidative stress in human trabecular meshwork cells. Int Ophthalmol 2024; 44:229. [PMID: 38795168 DOI: 10.1007/s10792-024-02917-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 12/24/2023] [Indexed: 05/27/2024]
Abstract
BACKGROUND The multifunctional profibrotic cytokine transforming growth factor-beta2 (TGF-β2) is implicated in the pathophysiology of primary open angle glaucoma. Paeoniflorin (PAE) is a monoterpene glycoside with multiple pharmacological efficacies, such as antioxidant, anti-fibrotic, and anti-inflammatory properties. Studies have demonstrated that paeoniflorin protects human corneal epithelial cells, retinal pigment epithelial cells, and retinal microglia from damage. Here, the biological role of PAE in TGF-β2-dependent remodeling of the extracellular matrix (ECM) within the trabecular meshwork (TM) microenvironment. METHODS Primary or transformed (GTM3) human TM (HTM) cells conditioned in serum-free media were incubated with TGF-β2 (5 ng/mL). PAE (300 μM) was added to serum-starved confluent cultures of HTM cells for 2 h, followed by incubation with TGF-β2 for 22 h. SB-431542, a TGF-β receptor inhibitor (10 μM), was used as a positive control. The levels of intracellular ROS were evaluated by CellROX green dye. Western blotting was used to measure the levels of TGF-β2/Smad2/3 signaling-related molecules. Collagen 1α1, collagen 4α1, and connective tissue growth factor (CTGF) expression was evaluated by RT-qPCR. Immunofluorescence assay was conducted to measure collagen I/IV expression in HTM cells. Phalloidin staining assay was conducted for evaluating F-actin stress fiber formation in the cells. RESULTS PAE attenuated TGF-β2-induced oxidative stress and suppressed TGF-β2-induced Smad2/3 signaling in primary or transformed HTM cells. Additionally, PAE repressed TGF-β2-induced upregulation of collagen 1α1, collagen 4α1, and CTGF expression and reduced TGF-β2-mediated collagen I/IV expression and of F-actin stress fiber formation in primary or transformed HTM cells. CONCLUSION PAE alleviates TGF-β2-induced ECM deposition and oxidative stress in HTM cells through inactivation of Smad2/3 signaling.
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Affiliation(s)
- Yongmei Hu
- Department of Ophthalmology, The First People's Hospital of Jiangxia District, Wuhan, No.1 Wenhua Avenue, Zhifang Street, Jiangxia District, Wuhan, 430200, China
| | - Kui Ge
- Department of Ophthalmology, The First People's Hospital of Jiangxia District, Wuhan, No.1 Wenhua Avenue, Zhifang Street, Jiangxia District, Wuhan, 430200, China
| | - Yan Du
- Department of Ophthalmology, The First People's Hospital of Jiangxia District, Wuhan, No.1 Wenhua Avenue, Zhifang Street, Jiangxia District, Wuhan, 430200, China.
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2
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Qian C, Xin Y, Qi C, Wang H, Dong BC, Zack DJ, Blackshaw S, Hattar S, Zhou FQ, Qian J. Intercellular communication atlas reveals Oprm1 as a neuroprotective factor for retinal ganglion cells. Nat Commun 2024; 15:2206. [PMID: 38467611 DOI: 10.1038/s41467-024-46428-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 02/26/2024] [Indexed: 03/13/2024] Open
Abstract
Previous studies of neuronal survival have primarily focused on identifying intrinsic mechanisms controlling the process. This study explored how intercellular communication contributes to retinal ganglion cell (RGC) survival following optic nerve crush based on single-cell RNA-seq analysis. We observed transcriptomic changes in retinal cells in response to the injury, with astrocytes and Müller glia having the most interactions with RGCs. By comparing RGC subclasses characterized by distinct resilience to cell death, we found that the high-survival RGCs tend to have more ligand-receptor interactions with neighboring cells. We identified 47 interactions stronger in high-survival RGCs, likely mediating neuroprotective effects. We validated one identified target, the μ-opioid receptor (Oprm1), to be neuroprotective in three retinal injury models. Although the endogenous Oprm1 is preferentially expressed in intrinsically photosensitive RGCs, its neuroprotective effect can be transferred to other subclasses by pan-RGC overexpression of Oprm1. Lastly, manipulating the Oprm1 activity improved visual functions in mice.
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Affiliation(s)
- Cheng Qian
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ying Xin
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Cheng Qi
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hui Wang
- Section on Light and Circadian Rhythms, National Institute of Mental Health, Bethesda, MD, USA
| | - Bryan C Dong
- Neuroscience Study Program, Krieger School of Arts & Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Donald J Zack
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Seth Blackshaw
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Samer Hattar
- Section on Light and Circadian Rhythms, National Institute of Mental Health, Bethesda, MD, USA
| | - Feng-Quan Zhou
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.
| | - Jiang Qian
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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3
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Tonti E, Dell'Omo R, Filippelli M, Spadea L, Salati C, Gagliano C, Musa M, Zeppieri M. Exploring Epigenetic Modifications as Potential Biomarkers and Therapeutic Targets in Glaucoma. Int J Mol Sci 2024; 25:2822. [PMID: 38474069 DOI: 10.3390/ijms25052822] [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: 02/07/2024] [Revised: 02/23/2024] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
Glaucoma, a complex and multifactorial neurodegenerative disorder, is a leading cause of irreversible blindness worldwide. Despite significant advancements in our understanding of its pathogenesis and management, early diagnosis and effective treatment of glaucoma remain major clinical challenges. Epigenetic modifications, encompassing deoxyribonucleic acid (DNA) methylation, histone modifications, and non-coding RNAs, have emerged as critical regulators of gene expression and cellular processes. The aim of this comprehensive review focuses on the emerging field of epigenetics and its role in understanding the complex genetic and molecular mechanisms underlying glaucoma. The review will provide an overview of the pathophysiology of glaucoma, emphasizing the intricacies of intraocular pressure regulation, retinal ganglion cell dysfunction, and optic nerve damage. It explores how epigenetic modifications, such as DNA methylation and histone modifications, can influence gene expression, and how these mechanisms are implicated in glaucomatous neurodegeneration and contribute to glaucoma pathogenesis. The manuscript discusses evidence from both animal models and human studies, providing insights into the epigenetic alterations associated with glaucoma onset and progression. Additionally, it discusses the potential of using epigenetic modifications as diagnostic biomarkers and therapeutic targets for more personalized and targeted glaucoma treatment.
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Affiliation(s)
- Emanuele Tonti
- Eye Clinic, Policlinico Umberto I University Hospital, 00142 Rome, Italy
| | - Roberto Dell'Omo
- Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Via Francesco De Sanctis 1, 86100 Campobasso, Italy
| | - Mariaelena Filippelli
- Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Via Francesco De Sanctis 1, 86100 Campobasso, Italy
| | - Leopoldo Spadea
- Eye Clinic, Policlinico Umberto I University Hospital, 00142 Rome, Italy
| | - Carlo Salati
- Department of Ophthalmology, University Hospital of Udine, 33100 Udine, Italy
| | - Caterina Gagliano
- Faculty of Medicine and Surgery, University of Enna "Kore", Piazza dell'Università, 94100 Enna, Italy
- Eye Clinic, Catania University, San Marco Hospital, Viale Carlo Azeglio Ciampi, 95121 Catania, Italy
| | - Mutali Musa
- Department of Optometry, University of Benin, Benin City 300238, Nigeria
| | - Marco Zeppieri
- Department of Ophthalmology, University Hospital of Udine, 33100 Udine, Italy
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4
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Ji Y, Li J, Liu S, Zhu J, Yao J, Li KR, Yan B. Identification of circular RNA-Dcaf6 as a therapeutic target for optic nerve crush-induced RGC degeneration. Genomics 2024; 116:110776. [PMID: 38163571 DOI: 10.1016/j.ygeno.2023.110776] [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: 09/14/2023] [Revised: 11/30/2023] [Accepted: 12/29/2023] [Indexed: 01/03/2024]
Abstract
The death of retinal ganglion cells (RGCs) can cause irreversible injury in visual function. Clarifying the mechanism of RGC degeneration is critical for the development of therapeutic strategies. Circular RNAs (circRNAs) are important regulators in many biological and pathological processes. Herein, we performed circRNA microarrays to identify dysregulated circRNAs following optic nerve crush (ONC). The results showed that 221 circRNAs were differentially expressed between ONC retinas and normal retinas. Notably, the levels of circular RNA-Dcaf6 (cDcaf6) expression in aqueous humor of glaucoma patients were higher than that in cataract patients. cDcaf6 silencing could reduce oxidative stress-induced RGC apoptosis in vitro and alleviate retinal neurodegeneration in vivo as shown by increased neuronal nuclei antigen (NeuN, neuronal bodies) and beta-III-tubulin (TUBB3, neuronal filaments) staining and reduced glial fibrillary acidic protein (GFAP, activated glial cells) and vimentin (activated glial cells) staining. Collectively, this study identifies a promising target for treating retinal neurodegeneration.
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Affiliation(s)
- Yuke Ji
- Department of Ophthalmology and Optometry, The Affiliated Eye Hospital, Nanjing Medical University, Nanjing, China; Department of Ophthalmology and Optometry, The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Jing Li
- Eye Institute and Department of Ophthalmology, Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, China
| | - Sha Liu
- Department of Ophthalmology and Optometry, The Affiliated Eye Hospital, Nanjing Medical University, Nanjing, China; Department of Ophthalmology and Optometry, The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Junya Zhu
- Department of Ophthalmology and Optometry, The Affiliated Eye Hospital, Nanjing Medical University, Nanjing, China; Department of Ophthalmology and Optometry, The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Jin Yao
- Department of Ophthalmology and Optometry, The Affiliated Eye Hospital, Nanjing Medical University, Nanjing, China; Department of Ophthalmology and Optometry, The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China.
| | - Ke-Ran Li
- Department of Ophthalmology and Optometry, The Affiliated Eye Hospital, Nanjing Medical University, Nanjing, China; Department of Ophthalmology and Optometry, The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing, China.
| | - Biao Yan
- Eye Institute and Department of Ophthalmology, Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, China; NHC Key Laboratory of Myopia Fudan University, Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China; Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China.
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5
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Feng L, Wang C, Zhang C, Zhang W, Song W. Role of epigenetic regulation in glaucoma. Biomed Pharmacother 2023; 168:115633. [PMID: 37806089 DOI: 10.1016/j.biopha.2023.115633] [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: 08/16/2023] [Revised: 09/23/2023] [Accepted: 10/03/2023] [Indexed: 10/10/2023] Open
Abstract
Glaucoma is the world's leading irreversible blinding eye disease. Lowering intraocular pressure is currently the only effective clinical treatment. However, there is a lack of long-acting IOP-lowering drugs, and some patients still experience retinal ganglion cell loss even with good intraocular pressure control. Currently, there is no effective method for neuroprotection and regeneration in clinical practice for glaucoma. In recent years, epigenetics has been widely researched and reported for its role in glaucoma's neuroprotection and regeneration. This article reviews the changes in histone modifications, DNA methylation, non-coding RNA, and m6A methylation in glaucoma, aiming to provide new perspectives for glaucoma management, protection of retinal ganglion cells, and axon regeneration by understanding epigenetic alterations.
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Affiliation(s)
- Lemeng Feng
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital of Central South University, Changsha, Hunan 410008, PR China; Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Hunan Key Laboratory of Ophthalmology, Changsha, Hunan 410008, PR China
| | - Chao Wang
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital of Central South University, Changsha, Hunan 410008, PR China; Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Hunan Key Laboratory of Ophthalmology, Changsha, Hunan 410008, PR China
| | - Cheng Zhang
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital of Central South University, Changsha, Hunan 410008, PR China; Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Hunan Key Laboratory of Ophthalmology, Changsha, Hunan 410008, PR China
| | - Wulong Zhang
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital of Central South University, Changsha, Hunan 410008, PR China; Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Hunan Key Laboratory of Ophthalmology, Changsha, Hunan 410008, PR China
| | - Weitao Song
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital of Central South University, Changsha, Hunan 410008, PR China; Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Hunan Key Laboratory of Ophthalmology, Changsha, Hunan 410008, PR China.
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6
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Vasconcelos CFM, Ribas VT, Petrs-Silva H. Shared Molecular Pathways in Glaucoma and Other Neurodegenerative Diseases: Insights from RNA-Seq Analysis and miRNA Regulation for Promising Therapeutic Avenues. Cells 2023; 12:2155. [PMID: 37681887 PMCID: PMC10486375 DOI: 10.3390/cells12172155] [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: 07/29/2023] [Revised: 08/14/2023] [Accepted: 08/21/2023] [Indexed: 09/09/2023] Open
Abstract
Advances in RNA-sequencing technologies have led to the identification of molecular biomarkers for several diseases, including neurodegenerative diseases, such as Alzheimer's, Parkinson's, Huntington's diseases and Amyotrophic Lateral Sclerosis. Despite the nature of glaucoma as a neurodegenerative disorder with several similarities with the other above-mentioned diseases, transcriptional data about this disease are still scarce. microRNAs are small molecules (~17-25 nucleotides) that have been found to be specifically expressed in the CNS as major components of the system regulating the development signatures of neurodegenerative diseases and the homeostasis of the brain. In this review, we sought to identify similarities between the functional mechanisms and the activated pathways of the most common neurodegenerative diseases, as well as to discuss how those mechanisms are regulated by miRNAs, using RNA-Seq as an approach to compare them. We also discuss therapeutically suitable applications for these disease hallmarks in clinical future studies.
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Affiliation(s)
- Carlos Franciney Moreira Vasconcelos
- University of Medicine of Göttingen, 37075 Göttingen, Germany
- Institute of Biophysics Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Vinicius Toledo Ribas
- Institute of Biological Sciences, Universidade Federal de Minas Gerais (ICB/UFMG), Belo Horizonte 31270-901, Brazil;
| | - Hilda Petrs-Silva
- Institute of Biophysics Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
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7
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Qian C, Xin Y, Cheng Q, Wang H, Zack D, Blackshaw S, Hattar S, Feng-Quan Z, Qian J. Intercellular communication atlas reveals Oprm1 as a neuroprotective factor for retinal ganglion cells. RESEARCH SQUARE 2023:rs.3.rs-3193738. [PMID: 37645816 PMCID: PMC10462234 DOI: 10.21203/rs.3.rs-3193738/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The progressive death of mature neurons often results in neurodegenerative diseases. While the previous studies have mostly focused on identifying intrinsic mechanisms controlling neuronal survival, the extracellular environment also plays a critical role in regulating cell viability. Here we explore how intercellular communication contributes to the survival of retinal ganglion cells (RGCs) following the optic nerve crush (ONC). Although the direct effect of the ONC is restricted to the RGCs, we observed transcriptomic responses in other retinal cells to the injury based on the single-cell RNA-seq, with astrocytes and Müller glia having the most interactions with RGCs. By comparing the RGC subclasses showing distinct resilience to ONC-induced cell death, we found that the high-survival RGCs tend to have more ligand-receptor interactions with other retinal cells, suggesting that these RGCs are intrinsically programmed to foster more communication with their surroundings. Furthermore, we identified top 47 interactions that are stronger in the high-survival RGCs, likely representing neuroprotective interactions. We performed functional assays on one of the receptors, μ opioid receptor (Oprm1), a receptor known to play roles in regulating pain, reward, and addictive behavior. Although Oprm1 is preferentially expressed in intrinsically photosensitive retinal ganglion cells (ipRGCs), its neuroprotective effect could be transferred to multiple RGC subclasses by specific overexpressing Oprm1 in pan-RGCs in ONC, excitotoxicity, and glaucoma models. Lastly, manipulating Oprm1 activity improved visual functions and altered pupillary light response in mice. Our study provides an atlas of cell-cell interactions in both intact and post-ONC retina and an effective strategy to predict molecular mechanisms in neuroprotection, underlying the principal role played by extracellular environment in supporting neuron survival.
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Affiliation(s)
- Cheng Qian
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Ying Xin
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Qi Cheng
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Hui Wang
- Section on Light and Circadian Rhythms, National Institute of Mental Health, Bethesda, Maryland, United States
| | - Donald Zack
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Seth Blackshaw
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Samer Hattar
- Section on Light and Circadian Rhythms, National Institute of Mental Health, Bethesda, Maryland, United States
| | - Zhou Feng-Quan
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, United States
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
- Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jiang Qian
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, United States
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8
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Li J, Zhu Y, Xu M, Li P, Zhou Y, Song Y, Cai Q. Physcion prevents induction of optic nerve injury in rats via inhibition of the JAK2/STAT3 pathway. Exp Ther Med 2023; 26:381. [PMID: 37456161 PMCID: PMC10347236 DOI: 10.3892/etm.2023.12080] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 04/26/2023] [Indexed: 07/18/2023] Open
Abstract
Optic nerve injury is a type of neurodegenerative disease. Physcion is an anthraquinone that exerts a protective role against various diseases. However, its function in regulating optic nerve injury remains largely unknown. An in vitro model of optic nerve injury was established in HAPI cells treated with IFN-β. Functional assays were used to detect HAPI cell viability and apoptosis. The levels of inflammation and the expression levels of oxidative stress-related genes were measured in HAPI cells. In addition, western blot analysis was used to detect the expression levels of Janus kinase 2 (JAK2)/STAT3-linked genes in HAPI cells. Treatment of the cells with physcion prevented cells against IFN-β-induced neuronal injury. Physcion restrained IFN-β-induced inflammatory response and oxidative stress in HAPI cells. In addition, it improved IFN-β-induced injury in HAPI cells by suppressing the JAK2/STAT3 pathway. In conclusion, the present study revealed that physcion improved optic nerve injury in vitro by inhibiting the JAK2/STAT3 pathway. Physcion may be a promising therapeutic target for the treatment of this disease.
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Affiliation(s)
- Jingjing Li
- Department of Ophthalmology, The Second Affiliated Hospital of Nantong University (Nantong First People's Hospital), Nantong, Jiangsu 226006, P.R. China
| | - Yan Zhu
- Department of Ophthalmology, The Second Affiliated Hospital of Nantong University (Nantong First People's Hospital), Nantong, Jiangsu 226006, P.R. China
| | - Mudong Xu
- Department of Ophthalmology, The Second Affiliated Hospital of Nantong University (Nantong First People's Hospital), Nantong, Jiangsu 226006, P.R. China
| | - Panpan Li
- Department of Ophthalmology, The Second Affiliated Hospital of Nantong University (Nantong First People's Hospital), Nantong, Jiangsu 226006, P.R. China
| | - Yue Zhou
- Department of Ophthalmology, The Second Affiliated Hospital of Nantong University (Nantong First People's Hospital), Nantong, Jiangsu 226006, P.R. China
| | - Yu Song
- Department of Ophthalmology, The Second Affiliated Hospital of Nantong University (Nantong First People's Hospital), Nantong, Jiangsu 226006, P.R. China
| | - Qi Cai
- Department of Ophthalmology, The Second Affiliated Hospital of Nantong University (Nantong First People's Hospital), Nantong, Jiangsu 226006, P.R. China
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9
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Guo L, Xie X, Wang J, Xiao H, Li S, Xu M, Quainoo E, Koppaka R, Zhuo J, Smith SB, Gan L. Inducible Rbpms-CreER T2 Mouse Line for Studying Gene Function in Retinal Ganglion Cell Physiology and Disease. Cells 2023; 12:1951. [PMID: 37566030 PMCID: PMC10416940 DOI: 10.3390/cells12151951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/14/2023] [Accepted: 07/25/2023] [Indexed: 08/12/2023] Open
Abstract
Retinal ganglion cells (RGCs) are the sole output neurons conveying visual stimuli from the retina to the brain, and dysfunction or loss of RGCs is the primary determinant of visual loss in traumatic and degenerative ocular conditions. Currently, there is a lack of RGC-specific Cre mouse lines that serve as invaluable tools for manipulating genes in RGCs and studying the genetic basis of RGC diseases. The RNA-binding protein with multiple splicing (RBPMS) is identified as the specific marker of all RGCs. Here, we report the generation and characterization of a knock-in mouse line in which a P2A-CreERT2 coding sequence is fused in-frame to the C-terminus of endogenous RBPMS, allowing for the co-expression of RBPMS and CreERT2. The inducible Rbpms-CreERT2 mice exhibited a high recombination efficiency in activating the expression of the tdTomato reporter gene in nearly all adult RGCs as well as in differentiated RGCs starting at E13.5. Additionally, both heterozygous and homozygous Rbpms-CreERT2 knock-in mice showed no detectable defect in the retinal structure, visual function, and transcriptome. Together, these results demonstrated that the Rbpms-CreERT2 knock-in mouse can serve as a powerful and highly desired genetic tool for lineage tracing, genetic manipulation, retinal physiology study, and ocular disease modeling in RGCs.
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Affiliation(s)
- Luming Guo
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Xiaoling Xie
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Jing Wang
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- James and Jean Culver Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Haiyan Xiao
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- James and Jean Culver Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Shuchun Li
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Mei Xu
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Ebenezer Quainoo
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- James and Jean Culver Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Rithwik Koppaka
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Jiaping Zhuo
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Sylvia B. Smith
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- James and Jean Culver Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Lin Gan
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- James and Jean Culver Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
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10
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Qian C, Xin Y, Qi C, Wang H, Dong BC, Zack D, Blackshaw S, Hattar S, Zhou FQ, Qian J. Intercellular communication atlas reveals Oprm1 as a neuroprotective factor for retinal ganglion cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.14.549118. [PMID: 37502873 PMCID: PMC10370148 DOI: 10.1101/2023.07.14.549118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
The progressive death of mature neurons often results in neurodegenerative diseases. While the previous studies have mostly focused on identifying intrinsic mechanisms controlling neuronal survival, the extracellular environment also plays a critical role in regulating cell viability. Here we explore how intercellular communication contributes to the survival of retinal ganglion cells (RGCs) following the optic nerve crush (ONC). Although the direct effect of the ONC is restricted to the RGCs, we observed transcriptomic responses in other retinal cells to the injury based on the single-cell RNA-seq, with astrocytes and Müller glia having the most interactions with RGCs. By comparing the RGC subclasses with distinct resilience to ONC-induced cell death, we found that the high-survival RGCs tend to have more ligand-receptor interactions with other retinal cells, suggesting that these RGCs are intrinsically programmed to foster more communication with their surroundings. Furthermore, we identified the top 47 interactions that are stronger in the high-survival RGCs, likely representing neuroprotective interactions. We performed functional assays on one of the receptors, μ-opioid receptor (Oprm1), a receptor known to play roles in regulating pain, reward, and addictive behavior. Although Oprm1 is preferentially expressed in intrinsically photosensitive retinal ganglion cells (ipRGC), its neuroprotective effect could be transferred to multiple RGC subclasses by selectively overexpressing Oprm1 in pan-RGCs in ONC, excitotoxicity, and glaucoma models. Lastly, manipulating Oprm1 activity improved visual functions or altered pupillary light response in mice. Our study provides an atlas of cell-cell interactions in intact and post-ONC retina, and a strategy to predict molecular mechanisms controlling neuroprotection, underlying the principal role played by extracellular environment in supporting neuron survival.
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Lagali PS, Shanmugalingam U, Baker AN, Mezey N, Smith PD, Coupland SG, Tsilfidis C. Assessment of the uniform field electroretinogram for mouse retinal ganglion cell functional analysis. Doc Ophthalmol 2023:10.1007/s10633-023-09933-y. [PMID: 37106219 DOI: 10.1007/s10633-023-09933-y] [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: 06/24/2022] [Accepted: 03/26/2023] [Indexed: 04/29/2023]
Abstract
PURPOSE The uniform field electroretinogram (UF-ERG) has been suggested as an alternative to the pattern electroretinogram (PERG) for non-invasive assessment of retinal ganglion cell (RGC) function in primates. We evaluated the validity of the UF-ERG to assess mouse RGC activity in vivo. METHODS Unilateral optic nerve crush (ONC) was performed on adult C57BL/6J mice. Contralateral eyes with uncrushed optic nerves and eyes from surgically naive mice served as experimental controls. Electrophysiological visual assessment was performed at 12 weeks post-ONC. Flash-mediated visual-evoked cortical potentials (VEPs) were measured to confirm the robustness of the ONC procedure. Full-field flash ERGs were used to interrogate photoreceptor and retinal bipolar cell function. RGC function was assessed with pattern ERGs. Summed onset and offset UF-ERG responses to alternating dark and light uniform field flash stimuli of different intensities and wavelengths were recorded from ONC and control eyes, and relative differences were compared to the PERG results. Following electrophysiological analysis, RGC loss was monitored by immunohistochemical staining of the RGC marker protein, RBPMS, in post-mortem retinal tissues. RESULTS ONC dramatically impacts RGC integrity and optic nerve function, demonstrated by reduced RGC counts and near complete elimination of VEPs. ONC did not affect scotopic ERG a-wave and b-wave amplitudes, while PERG amplitudes of eyes subjected to ONC were reduced by approximately 50% compared to controls. Summation of ON and OFF UF-ERG responses did not reveal statistically significant differences between ONC and control eyes, regardless of visual stimulus. CONCLUSIONS PERG responses are markedly impaired upon ONC, while UF-ERG responses are not significantly affected by surgical trauma to RGC axons in mice. The more closely related pattern and uniform field ERGs recorded in primates suggests species-specific differences in RGC features or subpopulations corresponding to PERG and UF-ERG response generators, limiting the utility of the UF-ERG for mouse RGC functional analysis.
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Affiliation(s)
- Pamela S Lagali
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, ON, K1H 8L6, Canada
- University of Ottawa Eye Institute, The Ottawa Hospital, Ottawa, ON, K1H 8L6, Canada
| | | | - Adam N Baker
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, ON, K1H 8L6, Canada
- University of Ottawa Eye Institute, The Ottawa Hospital, Ottawa, ON, K1H 8L6, Canada
| | - Natalie Mezey
- Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | - Patrice D Smith
- Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | - Stuart G Coupland
- University of Ottawa Eye Institute, The Ottawa Hospital, Ottawa, ON, K1H 8L6, Canada
- Department of Ophthalmology, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Catherine Tsilfidis
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, ON, K1H 8L6, Canada.
- University of Ottawa Eye Institute, The Ottawa Hospital, Ottawa, ON, K1H 8L6, Canada.
- Department of Ophthalmology, University of Ottawa, Ottawa, ON, K1H 8M5, Canada.
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada.
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12
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Chucair-Elliott AJ, Ocañas SR, Pham K, Van Der Veldt M, Cheyney A, Stanford D, Gurley J, Elliott MH, Freeman WM. Translatomic response of retinal Müller glia to acute and chronic stress. Neurobiol Dis 2022; 175:105931. [PMID: 36423879 PMCID: PMC9875566 DOI: 10.1016/j.nbd.2022.105931] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 11/14/2022] [Accepted: 11/19/2022] [Indexed: 11/23/2022] Open
Abstract
Analysis of retina cell type-specific epigenetic and transcriptomic signatures is crucial to understanding the pathophysiology of retinal degenerations such as age-related macular degeneration (AMD) and delineating cell autonomous and cell-non-autonomous mechanisms. We have discovered that Aldh1l1 is specifically expressed in the major macroglia of the retina, Müller glia, and, unlike the brain, is not expressed in retinal astrocytes. This allows use of Aldh1l1 cre drivers and Nuclear Tagging and Translating Ribosome Affinity Purification (NuTRAP) constructs for temporally controlled labeling and paired analysis of Müller glia epigenomes and translatomes. As validated through a variety of approaches, the Aldh1l1cre/ERT2-NuTRAP model provides Müller glia specific translatomic and epigenomic profiles without the need to isolate whole cells. Application of this approach to models of acute injury (optic nerve crush) and chronic stress (aging) uncovered few common Müller glia-specific transcriptome changes in inflammatory pathways, and mostly differential signatures for each stimulus. The expression of members of the IL-6 and integrin-linked kinase signaling pathways was enhanced in Müller glia in response to optic nerve crush but not aging. Unique changes in neuroinflammation and fibrosis signaling pathways were observed in response to aging but not with optic nerve crush. The Aldh1l1cre/ERT2-NuTRAP model allows focused molecular analyses of a single, minority cell type within the retina, providing more substantial effect sizes than whole tissue analyses. The NuTRAP model, nucleic acid isolation, and validation approaches presented here can be applied to any retina cell type for which a cell type-specific cre is available.
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Affiliation(s)
- Ana J. Chucair-Elliott
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA,Corresponding authors at: Genes & Human Disease Program, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK 73104, USA. (A.J. Chucair-Elliott), (W.M. Freeman)
| | - Sarah R. Ocañas
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA,Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Kevin Pham
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Michael Van Der Veldt
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Ashley Cheyney
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA,Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - David Stanford
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Jami Gurley
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, 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,Corresponding authors at: Genes & Human Disease Program, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK 73104, USA. (A.J. Chucair-Elliott), (W.M. Freeman)
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13
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Li L, Feng X, Fang F, Miller DA, Zhang S, Zhuang P, Huang H, Liu P, Liu J, Sredar N, Liu L, Sun Y, Duan X, Goldberg JL, Zhang HF, Hu Y. Longitudinal in vivo Ca 2+ imaging reveals dynamic activity changes of diseased retinal ganglion cells at the single-cell level. Proc Natl Acad Sci U S A 2022; 119:e2206829119. [PMID: 36409915 PMCID: PMC9889883 DOI: 10.1073/pnas.2206829119] [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: 04/19/2022] [Accepted: 10/05/2022] [Indexed: 11/22/2022] Open
Abstract
Retinal ganglion cells (RGCs) are heterogeneous projection neurons that convey distinct visual features from the retina to brain. Here, we present a high-throughput in vivo RGC activity assay in response to light stimulation using noninvasive Ca2+ imaging of thousands of RGCs simultaneously in living mice. Population and single-cell analyses of longitudinal RGC Ca2+ imaging reveal distinct functional responses of RGCs and unprecedented individual RGC activity conversions during traumatic and glaucomatous degeneration. This study establishes a foundation for future in vivo RGC function classifications and longitudinal activity evaluations using more advanced imaging techniques and visual stimuli under normal, disease, and neural repair conditions. These analyses can be performed at both the population and single-cell levels using temporal and spatial information, which will be invaluable for understanding RGC pathophysiology and identifying functional biomarkers for diverse optic neuropathies.
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Affiliation(s)
- Liang Li
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
| | - Xue Feng
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
| | - Fang Fang
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha410011, China
| | - David A. Miller
- Department of Biomedical Engineering, Northwestern University, Evanston, IL60208
| | - Shaobo Zhang
- Department of Ophthalmology, University of California San Francisco, San Francisco, CA94143
| | - Pei Zhuang
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
| | - Haoliang Huang
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
| | - Pingting Liu
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
| | - Junting Liu
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
| | - Nripun Sredar
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
| | - Liang Liu
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
| | - Yang Sun
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
| | - Xin Duan
- Department of Ophthalmology, University of California San Francisco, San Francisco, CA94143
| | - Jeffrey L. Goldberg
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
| | - Hao F. Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston, IL60208
| | - Yang Hu
- Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute at Stanford University School of Medicine, Palo Alto, CA94304
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14
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Fuellen G, Jünemann A. Gene Expression Data for Investigating Glaucoma Treatment Options and Pharmacology in the Anterior Segment, State-of-the-Art and Future Directions. Front Neurosci 2022; 16:912043. [PMID: 35757536 PMCID: PMC9213806 DOI: 10.3389/fnins.2022.912043] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 05/20/2022] [Indexed: 11/30/2022] Open
Abstract
Glaucoma treatment options as well as its etiology are far from understood. Gene expression (transcriptomics) data of the anterior segment of the eye can help by elucidating the molecular-mechanistic underpinnings, and we present an up-to-date description and discussion of what gene expression data are publicly available, and for which purposes these can be used. We feature the few resources covering all segments of the eye, and we then specifically focus on the anterior segment, and provide an extensive list of the Gene Expression Omnibus data that may be useful. We also feature single-cell data of relevance, particularly three datasets from tissues of relevance to aqueous humor outflow. We describe how the data have been used by researchers, by following up resource citations and data re-analyses. We discuss datasets and analyses pertaining to fibrosis following glaucoma surgery, and to glaucoma resulting from the use of steroids. We conclude by pointing out the current lack and underutilization of ocular gene expression data, and how the state of the art is expected to improve in the future.
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Affiliation(s)
- Georg Fuellen
- Institute for Biostatistics and Informatics in Medicine and Aging Research, Rostock University Medical Center, Rostock, Germany
| | - Anselm Jünemann
- Institute for Biostatistics and Informatics in Medicine and Aging Research, Rostock University Medical Center, Rostock, Germany
- Department of Ophthalmology, Rostock University Medical Center, Rostock, Germany
- Department of General Ophthalmology and Pediatric Ophthalmology Service, Medical University of Lublin, Lublin, Poland
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15
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Ahmed M, Kojima Y, Masai I. Strip1 regulates retinal ganglion cell survival by suppressing Jun-mediated apoptosis to promote retinal neural circuit formation. eLife 2022; 11:74650. [PMID: 35314028 PMCID: PMC8940179 DOI: 10.7554/elife.74650] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 02/04/2022] [Indexed: 12/13/2022] Open
Abstract
In the vertebrate retina, an interplay between retinal ganglion cells (RGCs), amacrine (AC), and bipolar (BP) cells establishes a synaptic layer called the inner plexiform layer (IPL). This circuit conveys signals from photoreceptors to visual centers in the brain. However, the molecular mechanisms involved in its development remain poorly understood. Striatin-interacting protein 1 (Strip1) is a core component of the striatin-interacting phosphatases and kinases (STRIPAK) complex, and it has shown emerging roles in embryonic morphogenesis. Here, we uncover the importance of Strip1 in inner retina development. Using zebrafish, we show that loss of Strip1 causes defects in IPL formation. In strip1 mutants, RGCs undergo dramatic cell death shortly after birth. AC and BP cells subsequently invade the degenerating RGC layer, leading to a disorganized IPL. Mechanistically, zebrafish Strip1 interacts with its STRIPAK partner, Striatin 3 (Strn3), and both show overlapping functions in RGC survival. Furthermore, loss of Strip1 or Strn3 leads to activation of the proapoptotic marker, Jun, within RGCs, and Jun knockdown rescues RGC survival in strip1 mutants. In addition to its function in RGC maintenance, Strip1 is required for RGC dendritic patterning, which likely contributes to proper IPL formation. Taken together, we propose that a series of Strip1-mediated regulatory events coordinates inner retinal circuit formation by maintaining RGCs during development, which ensures proper positioning and neurite patterning of inner retinal neurons. The back of the eye is lined with an intricate tissue known as the retina, which consists of carefully stacked neurons connecting to each other in well-defined ‘synaptic’ layers. Near the surface, photoreceptors cells detect changes in light levels, before passing this information through the inner plexiform layer to retinal ganglion cells (or RGCs) below. These neurons will then relay the visual signals to the brain. Despite the importance of this inner retinal circuit, little is known about how it is created as an organism develops. As a response, Ahmed et al. sought to identify which genes are essential to establish the inner retinal circuit, and how their absence affects retinal structure. To do this, they introduced random errors in the genetic code of zebrafish and visualised the resulting retinal circuits in these fast-growing, translucent fish. Initial screening studies found fish with mutations in a gene encoding a protein called Strip1 had irregular layering of the inner retina. Further imaging experiments to pinpoint the individual neurons affected showed that in zebrafish without Strip1, RGCs died in the first few days of development. Consequently, other neurons moved into the RGC layer to replace the lost cells, leading to layering defects. Ahmed et al. concluded that Strip1 promotes RGC survival and thereby coordinates proper positioning of neurons in the inner retina. In summary, these findings help to understand how the inner retina is wired; they could also shed light on the way other layered structures are established in the nervous system. Moreover, this study paves the way for future research investigating Strip1 as a potential therapeutic target to slow down the death of RGCs in conditions such as glaucoma.
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Affiliation(s)
- Mai Ahmed
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University
| | - Yutaka Kojima
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University
| | - Ichiro Masai
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University
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16
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Enz TJ, Tribble JR, Williams PA. Comparison of Glaucoma-Relevant Transcriptomic Datasets Identifies Novel Drug Targets for Retinal Ganglion Cell Neuroprotection. J Clin Med 2021; 10:3938. [PMID: 34501387 PMCID: PMC8432026 DOI: 10.3390/jcm10173938] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 08/10/2021] [Accepted: 08/27/2021] [Indexed: 12/20/2022] Open
Abstract
Glaucoma is a leading cause of blindness and is characterized by the progressive dysfunction and irreversible death of retinal ganglion cells. We aimed to identify shared differentially expressed genes (DE genes) between different glaucoma relevant models of retinal ganglion cell injury using existing RNA-sequencing data, thereby discovering targets for neuroprotective therapies. A comparison of DE genes from publicly available transcriptomic datasets identified 12 shared DE genes. The Comparative Toxicogenomics Database (CTD) was screened for compounds targeting a significant proportion of the identified DE genes. Forty compounds were identified in the CTD that interact with >50% of these shared DE genes. We next validated this approach by testing select compounds for an effect on retinal ganglion cell survival using a mouse retinal explant model. Folic acid, genistein, SB-431542, valproic acid, and WY-14643 (pirinixic acid) were tested. Folic acid, valproic acid, and WY-14643 demonstrated significant protection against retinal ganglion cell death in this model. The increasing prevalence of open access-omics data presents a resource to discover targets for future therapeutic investigation.
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Affiliation(s)
| | | | - Pete A. Williams
- Department of Clinical Neuroscience, Division of Eye and Vision, St. Erik Eye Hospital, Karolinska Institutet, 171 64 Stockholm, Sweden; (T.J.E.); (J.R.T.)
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