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Sun Y, Chen D, Dai T, Yu Z, Xie H, Wang X, Zhang W. Cell-free fat extract promotes axon regeneration and retinal ganglion cells survival in traumatic optic neuropathy. Front Cell Neurosci 2024; 18:1344853. [PMID: 38515790 PMCID: PMC10954833 DOI: 10.3389/fncel.2024.1344853] [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: 11/26/2023] [Accepted: 02/27/2024] [Indexed: 03/23/2024] Open
Abstract
Injuries to axons within the central nervous system (CNS) pose a substantial clinical challenge due to their limited regenerative capacity. This study investigates the therapeutic potential of Cell-free fat extract (CEFFE) in CNS injury. CEFFE was injected intravitreally after the optic nerve was crushed. Two weeks post-injury, quantification of regenerated axons and survival rates of retinal ganglion cells (RGCs) were performed. Subsequently, comprehensive gene ontology (GO) an-notation elucidated the cellular origins and functional attributes of CEFFE components. Molecular mechanisms underlying CEFFE's therapeutic effects were explored through Western blotting (WB). Additionally, levels of inflammatory factors within CEFFE were determined using enzyme-linked immunosorbent assay (ELISA), and histological staining of microglia was conducted to assess its impact on neuroinflammation. CEFFE demonstrated a significant capacity to promote axon re-generation and enhance RGCs survival. GO annotation revealed the involvement of 146 proteins within CEFFE in axonogenesis and neurogenesis. WB analysis unveiled the multifaceted pathways through which CEFFE exerts its therapeutic effects. Elevated levels of inflammatory factors were detected through ELISA, and CEFFE exhibited a modulatory effect on microglial activation in the retinal tissue following optic nerve crush (ONC). The present study highlights the therapeutic promise of CEFFE in the management of CNS injuries, exemplified by its ability to foster axon regeneration and improve RGCs survival.
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Affiliation(s)
- Yiyu Sun
- Department of Wound Reconstructive Surgery, Tongji Hospital Affiliated to Tongji University, School of Medicine, Tongji University, Shanghai, China
| | - Di Chen
- Department of Neurosurgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Tao Dai
- Department of Wound Reconstructive Surgery, Tongji Hospital Affiliated to Tongji University, School of Medicine, Tongji University, Shanghai, China
| | - Ziyou Yu
- Shanghai Key Laboratory of Tissue Engineering, Department of Plastic and Reconstructive Surgery, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Hui Xie
- Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiangsheng Wang
- Department of Plastic and Reconstructive Surgery, Affiliated Hangzhou First People’s Hospital, School of Medicine, Westlake University, Hangzhou, Zhejiang, China
| | - Wenjie Zhang
- Shanghai Key Laboratory of Tissue Engineering, Department of Plastic and Reconstructive Surgery, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University, Shanghai, China
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2
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Lee J, Nguyen S, Bhattacharya S. Optic nerve regeneration: Potential treatment approaches. Curr Opin Pharmacol 2024; 74:102428. [PMID: 38171063 PMCID: PMC10922496 DOI: 10.1016/j.coph.2023.102428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 01/05/2024]
Abstract
The optic nerve, predominantly constituted by the axons of retinal ganglion cells (RGCs), lacks the ability to regenerate and re-establish function after injury. RGCs are crucial for visual function, and thus, RGC death contributes to the development of numerous progressive neurodegenerative optic neuropathies including glaucoma, ischemic optic neuropathy, and optic neuritis. Regenerating optic nerve axons poses numerous challenges due to factors such as the intricate and inhibitory conditions that exist within their environment, intrinsic breaks to regeneration, and the geometric tortuosity that offers physical hindrance to axon growth. However, recent research advancements offer hope for clinically meaningful regeneration for those who suffer from optic nerve damage. In this review, we highlight the current treatment approaches for optic nerve axon regeneration.
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Affiliation(s)
- Jessica Lee
- Bascom Palmer Eye Institute, Miller School of Medicine at University of Miami, Miami, FL, USA; College of Medicine, Northeast Ohio Medical University (NEOMED), Rootstown, OH, USA
| | - Sherilyn Nguyen
- Bascom Palmer Eye Institute, Miller School of Medicine at University of Miami, Miami, FL, USA; College of Osteopathic Medicine, Nova Southeastern University, Tampa, FL, USA
| | - Sanjoy Bhattacharya
- Bascom Palmer Eye Institute, Miller School of Medicine at University of Miami, Miami, FL, USA.
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3
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Tüfekci KK, Kaplan AA, Kaya A, Alrafiah A, Altun G, Aktaş A, Kaplan S. The potential protective effects of melatonin and omega-3 on the male rat optic nerve exposed to 900 MHz electromagnetic radiation during the prenatal period. Int J Neurosci 2023; 133:1424-1436. [PMID: 37712630 DOI: 10.1080/00207454.2023.2259078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/17/2023] [Accepted: 09/09/2023] [Indexed: 09/16/2023]
Abstract
BACKGROUND Due to children and adolescents' widespread use of electronic devices, researchers have focused on pre-and early postnatal electromagnetic field (EMF) exposure. However, little is known about the effects of EMF exposure on the optic nerve. The aim of study was to investigate the changes occurring in the optic nerve and the protective effects of melatonin (mel) and omega 3 (ω-3) in rats. METHODS Thirty-five pregnant rats were divided into seven groups, Cont, Sham, EMF, EMF + melatonin (EMF + Mel), EMF + ω3, Mel, and ω3. The EMF groups were exposed to 900 megahertz (MHz) EMF daily for two hours during pregnancy. After the experiment, the right optic nerve of each offspring rat was removed and fixed in glutaraldehyde. Thin and semi-thin sections were taken for electron microscopic and stereological analyses. Myelinated axon numbers, myelin sheath thicknesses, and axonal areas were estimated using stereological methods. RESULTS The groups had no significant differences regarding mean numbers of axons, mean axonal areas, or mean myelin sheath thicknesses (p > 0.05). Histological observations revealed impaired lamellae in the myelin sheath of most axons, and vacuolization was frequently observed between the myelin sheath and axon in the EMF-exposed group. The Mel and ω-3-treated EMF groups exhibited well-preserved myelinated nerve fibers and intact astrocytes and oligodendrocytes. CONCLUSIONS At the ultrastructural level, Mel and ω3 exhibits a neuroprotective effect on the optic nerve exposed to prenatal EMF. The protective effects of these antioxidants on oligodendrocytes, which play an essential role in myelin formation in the central nervous system, now require detailed investigation.
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Affiliation(s)
- Kıymet Kübra Tüfekci
- Department of Histology and Embryology, Faculty of Medicine, Kastamonu University, Kastamonu, Turkey
| | - Arife Ahsen Kaplan
- Department of Histology and Embryology, Faculty of Medicine, İstanbul Medipol University, İstanbul, Turkey
| | - Ayşenur Kaya
- Department of Histology and Embryology, Faculty of Medicine, Karamanoğlu Mehmetbey University, Karaman, Turkey
- Department of Histology and Embryology, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Aziza Alrafiah
- Medical Laboratory Sciences Department, Faculty of Applied Medical Sciences, King Abdul Aziz University, Jeddah, Saudi Arabia
| | - Gamze Altun
- Department of Histology and Embryology, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Abit Aktaş
- Department of Histology and Embryology, Faculty of Veterinary Medicine, İstanbul Cerrahpaşa University, İstanbul, Turkey
| | - Süleyman Kaplan
- Department of Histology and Embryology, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
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4
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Oprescu SN, Baumann N, Chen X, Sun Q, Zhao Y, Yue F, Wang H, Kuang S. Sox11 is enriched in myogenic progenitors but dispensable for development and regeneration of the skeletal muscle. Skelet Muscle 2023; 13:15. [PMID: 37705115 PMCID: PMC10498607 DOI: 10.1186/s13395-023-00324-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 08/24/2023] [Indexed: 09/15/2023] Open
Abstract
Transcription factors (TFs) play key roles in regulating differentiation and function of stem cells, including muscle satellite cells (MuSCs), a resident stem cell population responsible for postnatal regeneration of the skeletal muscle. Sox11 belongs to the Sry-related HMG-box (SOX) family of TFs that play diverse roles in stem cell behavior and tissue specification. Analysis of single-cell RNA-sequencing (scRNA-seq) datasets identify a specific enrichment of Sox11 mRNA in differentiating but not quiescent MuSCs. Consistent with the scRNA-seq data, Sox11 levels increase during differentiation of murine primary myoblasts in vitro. scRNA-seq data comparing muscle regeneration in young and old mice further demonstrate that Sox11 expression is reduced in aged MuSCs. Age-related decline of Sox11 expression is associated with reduced chromatin contacts within the topologically associating domains. Unexpectedly, Myod1Cre-driven deletion of Sox11 in embryonic myoblasts has no effects on muscle development and growth, resulting in apparently healthy muscles that regenerate normally. Pax7CreER- or Rosa26CreER- driven (MuSC-specific or global) deletion of Sox11 in adult mice similarly has no effects on MuSC differentiation or muscle regeneration. These results identify Sox11 as a novel myogenic differentiation marker with reduced expression in quiescent and aged MuSCs, but the specific function of Sox11 in myogenesis remains to be elucidated.
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Affiliation(s)
- Stephanie N Oprescu
- Department of Biological Sciences, Purdue University, West Lafayette, IN, 47907, USA
| | - Nick Baumann
- Department of Biological Sciences, Purdue University, West Lafayette, IN, 47907, USA
| | - Xiyue Chen
- Department of Animal Sciences, Purdue University, West Lafayette, IN, 47907, USA
| | - Qiang Sun
- Department of Orthopedics and Traumatology, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong; Center for Neuromusculoskeletal Restorative Medicine, Hong Kong Science Park, Hong Kong, China
| | - Yu Zhao
- Department of Orthopedics and Traumatology, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong; Center for Neuromusculoskeletal Restorative Medicine, Hong Kong Science Park, Hong Kong, China
| | - Feng Yue
- Department of Animal Sciences, Purdue University, West Lafayette, IN, 47907, USA
| | - Huating Wang
- Department of Orthopedics and Traumatology, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong; Center for Neuromusculoskeletal Restorative Medicine, Hong Kong Science Park, Hong Kong, China
| | - Shihuan Kuang
- Department of Biological Sciences, Purdue University, West Lafayette, IN, 47907, USA.
- Department of Animal Sciences, Purdue University, West Lafayette, IN, 47907, USA.
- Center for Cancer Research, Purdue University, West Lafayette, IN, 47907, USA.
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5
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McLaughlin T, Wang J, Jia L, Wu F, Wang Y, Wang JJ, Mu X, Zhang SX. Neuronal p58 IPK Protects Retinal Ganglion Cells Independently of Macrophage/Microglia Activation in Ocular Hypertension. Cells 2023; 12:1558. [PMID: 37371028 PMCID: PMC10297187 DOI: 10.3390/cells12121558] [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: 12/20/2022] [Revised: 01/10/2023] [Accepted: 01/12/2023] [Indexed: 06/29/2023] Open
Abstract
p58IPK is a multifaceted endoplasmic reticulum (ER) chaperone and a regulator of eIF2α kinases involved in a wide range of cellular processes including protein synthesis, ER stress response, and macrophage-mediated inflammation. Systemic deletion of p58IPK leads to age-related loss of retinal ganglion cells (RGC) and exacerbates RGC damage induced by ischemia/reperfusion and increased intraocular pressure (IOP), suggesting a protective role of p58IPK in the retina. However, the mechanisms remain elusive. Herein, we investigated the cellular mechanisms underlying the neuroprotection action of p58IPK using conditional knockout (cKO) mouse lines where p58IPK is deleted in retinal neurons (Chx10-p58IPK cKO) or in myeloid cells (Lyz2-p58IPK cKO). In addition, we overexpressed p58IPK by adeno-associated virus (AAV) in the retina to examine the effect of p58IPK on RGC survival after ocular hypertension (OHT) in wild type (WT) mice. Our results show that overexpression of p58IPK by AAV significantly improved RGC survival after OHT in WT mice, suggesting a protective effect of p58IPK on reducing RGC injury. Conditional knockout of p58IPK in retinal neurons or in myeloid cells did not alter retinal structure or cellular composition. However, a significant reduction in the b wave of light-adapted electroretinogram (ERG) was observed in Chx10-p58IPK cKO mice. Deletion of p58IPK in retinal neurons exacerbates RGC loss at 14 days after OHT. In contrast, deficiency of p58IPK in myeloid cells increased the microglia/macrophage activation but had no effect on RGC loss. We conclude that deletion of p58IPK in macrophages increases their activation, but does not influence RGC survival. These results suggest that the neuroprotective action of p58IPK is mediated by its expression in retinal neurons, but not in macrophages. Therefore, targeting p58IPK specifically in retinal neurons is a promising approach for the treatment of neurodegenerative retinal diseases including glaucoma.
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Affiliation(s)
- Todd McLaughlin
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, USA
| | - Jinli Wang
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, USA
| | - Liyun Jia
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, USA
- Beijing Tongren Hospital, Capital Medical University, Beijing 100005, China
| | - Fuguo Wu
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, USA
| | - Yaqin Wang
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, USA
- Taihe Hospital, Hubei University of Medicine, Shiyan 442005, China
| | - Joshua J. Wang
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, USA
| | - Xiuqian Mu
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, USA
- Department of Biochemistry, University at Buffalo, State University of New York, Buffalo, NY 14203, USA
| | - Sarah X. Zhang
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, USA
- Department of Biochemistry, University at Buffalo, State University of New York, Buffalo, NY 14203, USA
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6
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Masi M, Biundo F, Fiou A, Racchi M, Pascale A, Buoso E. The Labyrinthine Landscape of APP Processing: State of the Art and Possible Novel Soluble APP-Related Molecular Players in Traumatic Brain Injury and Neurodegeneration. Int J Mol Sci 2023; 24:ijms24076639. [PMID: 37047617 PMCID: PMC10095589 DOI: 10.3390/ijms24076639] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/21/2023] [Accepted: 03/29/2023] [Indexed: 04/05/2023] Open
Abstract
Amyloid Precursor Protein (APP) and its cleavage processes have been widely investigated in the past, in particular in the context of Alzheimer’s Disease (AD). Evidence of an increased expression of APP and its amyloidogenic-related cleavage enzymes, β-secretase 1 (BACE1) and γ-secretase, at the hit axon terminals following Traumatic Brain Injury (TBI), firstly suggested a correlation between TBI and AD. Indeed, mild and severe TBI have been recognised as influential risk factors for different neurodegenerative diseases, including AD. In the present work, we describe the state of the art of APP proteolytic processing, underlining the different roles of its cleavage fragments in both physiological and pathological contexts. Considering the neuroprotective role of the soluble APP alpha (sAPPα) fragment, we hypothesised that sAPPα could modulate the expression of genes of interest for AD and TBI. Hence, we present preliminary experiments addressing sAPPα-mediated regulation of BACE1, Isthmin 2 (ISM2), Tetraspanin-3 (TSPAN3) and the Vascular Endothelial Growth Factor (VEGFA), each discussed from a biological and pharmacological point of view in AD and TBI. We finally propose a neuroprotective interaction network, in which the Receptor for Activated C Kinase 1 (RACK1) and the signalling cascade of PKCβII/nELAV/VEGF play hub roles, suggesting that vasculogenic-targeting therapies could be a feasible approach for vascular-related brain injuries typical of AD and TBI.
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Affiliation(s)
- Mirco Masi
- Computational and Chemical Biology, Italian Institute of Technology, Via Morego 30, 16163 Genova, Italy
| | - Fabrizio Biundo
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA
| | - André Fiou
- Department of Drug Sciences, Pharmacology Section, University of Pavia, Via Taramelli 12/14, 27100 Pavia, Italy
| | - Marco Racchi
- Department of Drug Sciences, Pharmacology Section, University of Pavia, Via Taramelli 12/14, 27100 Pavia, Italy
| | - Alessia Pascale
- Department of Drug Sciences, Pharmacology Section, University of Pavia, Via Taramelli 12/14, 27100 Pavia, Italy
| | - Erica Buoso
- Department of Drug Sciences, Pharmacology Section, University of Pavia, Via Taramelli 12/14, 27100 Pavia, Italy
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA 02118, USA
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7
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Oprescu SN, Baumann N, Chen X, Sun Q, Zhao Y, Yue F, Wang H, Kuang S. Sox11 is enriched in myogenic progenitors but dispensable for development and regeneration of skeletal muscle. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.30.534956. [PMID: 37034612 PMCID: PMC10081271 DOI: 10.1101/2023.03.30.534956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Transcription factors (TFs) play key roles in regulating the differentiation and function of stem cells, including muscle satellite cells (MuSCs), a resident stem cell population responsible for postnatal regeneration of the skeletal muscle. Sox11 belongs to the Sry-related HMG-box (SOX) family of TFs that play diverse roles in stem cell behavior and tissue specification. Analysis of single-cell RNA-sequencing (scRNA-seq) datasets identify a specific enrichment of Sox11 mRNA in differentiating but not quiescent MuSCs. Consistent with the scRNA-seq data, Sox11 levels increase during differentiation of murine primary myoblasts in vitro. scRNA-seq data comparing muscle regeneration in young and old mice further demonstrate that Sox11 expression is reduced in aged MuSCs. Age-related decline of Sox11 expression is associated with reduced chromatin contacts within the topologically associated domains. Unexpectedly, Myod1 Cre -driven deletion of Sox11 in embryonic myoblasts has no effects on muscle development and growth, resulting in apparently healthy muscles that regenerate normally. Pax7 CreER or Rosa26 CreER driven (MuSC-specific or global) deletion of Sox11 in adult mice similarly has no effects on MuSC differentiation or muscle regeneration. These results identify Sox11 as a novel myogenic differentiation marker with reduced expression in quiescent and aged MuSCs, but the specific function of Sox11 in myogenesis remain to be elucidated.
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8
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Wu S, Mo X. Optic Nerve Regeneration in Diabetic Retinopathy: Potentials and Challenges Ahead. Int J Mol Sci 2023; 24:ijms24021447. [PMID: 36674963 PMCID: PMC9865663 DOI: 10.3390/ijms24021447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 12/31/2022] [Accepted: 01/09/2023] [Indexed: 01/15/2023] Open
Abstract
Diabetic retinopathy (DR), the most common microvascular compilation of diabetes, is the leading cause of vision loss and blindness worldwide. Recent studies indicate that retinal neuron impairment occurs before any noticeable vascular changes in DR, and retinal ganglion cell (RGC) degeneration is one of the earliest signs. Axons of RGCs have little capacity to regenerate after injury, clinically leading the visual functional defects to become irreversible. In the past two decades, tremendous progress has been achieved to enable RGC axon regeneration in animal models of optic nerve injury, which holds promise for neural repair and visual restoration in DR. This review summarizes these advances and discusses the potential and challenges for developing optic nerve regeneration strategies treating DR.
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Affiliation(s)
| | - Xiaofen Mo
- Correspondence: ; Tel.: +86-021-64377134
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9
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Reprogramming neurons for regeneration: The fountain of youth. Prog Neurobiol 2022; 214:102284. [PMID: 35533809 DOI: 10.1016/j.pneurobio.2022.102284] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 04/03/2022] [Accepted: 05/02/2022] [Indexed: 01/22/2023]
Abstract
Neurons in the central nervous system (CNS) are terminally differentiated cells that gradually lose their ability to support regeneration during maturation due to changes in transcriptomic and chromatin landscape. Similar transcriptomic changes also occur during development when stem cells differentiate into different types of somatic cells. Importantly, differentiated cells can be reprogrammed back to induced pluripotent stems cells (iPSCs) via global epigenetic remodeling by combined overexpression of pluripotent reprogramming factors, including Oct4, Sox2, Klf4, c-Myc, Nanog, and/or Lin28. Moreover, recent findings showed that many proneural transcription factors were able to convert non-neural somatic cells into neurons bypassing the pluripotent stage via direct reprogramming. Interestingly, many of these factors have recently been identified as key regulators of CNS neural regeneration. Recent studies indicated that these factors could rejuvenate mature CNS neurons back to a younger state through cellular state reprogramming, thus favoring regeneration. Here we will review some recent findings regarding the roles of genetic cellular state reprogramming in regulation of neural regeneration and explore the potential underlying molecular mechanisms. Moreover, by using newly emerging techniques, such as multiomics sequencing with big data analysis and Crispr-based gene editing, we will discuss future research directions focusing on better revealing cellular state reprogramming-induced remodeling of chromatin landscape and potential translational application.
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10
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Amin D, Kuwajima T. Differential Retinal Ganglion Cell Vulnerability, A Critical Clue for the Identification of Neuroprotective Genes in Glaucoma. FRONTIERS IN OPHTHALMOLOGY 2022; 2:905352. [PMID: 38983528 PMCID: PMC11182220 DOI: 10.3389/fopht.2022.905352] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 05/05/2022] [Indexed: 07/11/2024]
Abstract
Retinal ganglion cells (RGCs) are the neurons in the retina which directly project to the brain and transmit visual information along the optic nerve. Glaucoma, one of the leading causes of blindness, is characterized by elevated intraocular pressure (IOP) and degeneration of the optic nerve, which is followed by RGC death. Currently, there are no clinical therapeutic drugs or molecular interventions that prevent RGC death outside of IOP reduction. In order to overcome these major barriers, an increased number of studies have utilized the following combined analytical methods: well-established rodent models of glaucoma including optic nerve injury models and transcriptomic gene expression profiling, resulting in the successful identification of molecules and signaling pathways relevant to RGC protection. In this review, we present a comprehensive overview of pathological features in a variety of animal models of glaucoma and top differentially expressed genes (DEGs) depending on disease progression, RGC subtypes, retinal regions or animal species. By comparing top DEGs among those different transcriptome profiles, we discuss whether commonly listed DEGs could be defined as potential novel therapeutic targets in glaucoma, which will facilitate development of future therapeutic neuroprotective strategies for treatments of human patients in glaucoma.
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Affiliation(s)
- Dwarkesh Amin
- Department of Ophthalmology, The Louis J. Fox Center for Vision Restoration, The University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Takaaki Kuwajima
- Department of Ophthalmology, The Louis J. Fox Center for Vision Restoration, The University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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11
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Islam A, Tom VJ. The use of viral vectors to promote repair after spinal cord injury. Exp Neurol 2022; 354:114102. [PMID: 35513025 DOI: 10.1016/j.expneurol.2022.114102] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 04/21/2022] [Accepted: 04/27/2022] [Indexed: 11/16/2022]
Abstract
Spinal cord injury (SCI) is a devastating event that can permanently disrupt multiple modalities. Unfortunately, the combination of the inhibitory environment at a central nervous system (CNS) injury site and the diminished intrinsic capacity of adult axons for growth results in the failure for robust axonal regeneration, limiting the ability for repair. Delivering genetic material that can either positively or negatively modulate gene expression has the potential to counter the obstacles that hinder axon growth within the spinal cord after injury. A popular gene therapy method is to deliver the genetic material using viral vectors. There are considerations when deciding on a viral vector approach for a particular application, including the type of vector, as well as serotypes, and promoters. In this review, we will discuss some of the aspects to consider when utilizing a viral vector approach to as a therapy for SCI. Additionally, we will discuss some recent applications of gene therapy to target extrinsic and/or intrinsic barriers to promote axon regeneration after SCI in preclinical models. While still in early stages, this approach has potential to treat those living with SCI.
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Affiliation(s)
- Ashraful Islam
- Drexel University College of Medicine, Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Philadelphia, PA, USA
| | - Veronica J Tom
- Drexel University College of Medicine, Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Philadelphia, PA, USA.
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12
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Ibad RT, Quenech'du N, Prochiantz A, Moya KL. OTX2 stimulates adult retinal ganglion cell regeneration. Neural Regen Res 2022; 17:690-696. [PMID: 34380911 PMCID: PMC8504389 DOI: 10.4103/1673-5374.320989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Retinal ganglion cell (RGC) axons provide the only link between the light sensitive and photon transducing neural retina and visual centers of the brain. RGC axon degeneration occurs in a number of blinding diseases and the ability to stimulate axon regeneration from surviving ganglion cells could provide the anatomic substrate for restoration of vision. OTX2 is a homeoprotein transcription factor expressed in the retina and previous studies showed that, in response to stress, exogenous OTX2 increases the in vitro and in vivo survival of RGCs. Here we examined and quantified the effects of OTX2 on adult RGC axon regeneration in vitro and in vivo. The results show that exogenous OTX2 stimulates the regrowth of axons from RGCs in cultures of dissociated adult retinal cells and from explants of adult retinal tissue and that RGCs respond directly to OTX2 as regrowth is observed in cultures of purified adult rat RGCs. Importantly, after nerve crush in vivo, we observed a positive effect of OTX2 on the number of regenerating axons up to the optic chiasm within 14 days post crush and a very modest level of acuity absent in control mice. The effect of OTX2 on RGC survival and regeneration is of potential interest for degenerative diseases affecting this cell type. All animal procedures were approved by the local “Comié d’éιthique en expérimentation animale n°59” and authorization n° 00702.01 delivered March 28, 2014 by the French “Ministére de l’enseignement supérieur et de la recherche”.
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Affiliation(s)
- Raoul Torero Ibad
- Univ. Lille, CNRS, UMR 8523 - PhLAM - Physique des Lasers Atomes et Molécules, F-59000 Lille, France
| | - Nicole Quenech'du
- Centre for Interdisciplinary Research in Biology (CIRB), Collége de France, CNRS UMR 7241, INSERM U1050, Labex MemoLife, Paris Sciences et Lettres Research University, Paris, France
| | - Alain Prochiantz
- BrainEver, 74 rue du Faubourg Saint Antoine, 75012 Paris and Institute of Neurosciences, 320 Yeu Yang Rd, Shanghai 200031, China
| | - Kenneth L Moya
- Centre for Interdisciplinary Research in Biology (CIRB), Collége de France, CNRS UMR 7241, INSERM U1050, Labex MemoLife, Paris Sciences et Lettres Research University, Paris, France
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Systemic Treatment with Nicotinamide Riboside Is Protective in Two Mouse Models of Retinal Ganglion Cell Damage. Pharmaceutics 2021; 13:pharmaceutics13060893. [PMID: 34208613 PMCID: PMC8235058 DOI: 10.3390/pharmaceutics13060893] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/20/2021] [Accepted: 06/10/2021] [Indexed: 11/26/2022] Open
Abstract
Glaucoma etiology often includes retinal ganglion cell (RGC) death associated with elevated intraocular pressure (IOP). However, even when IOP is managed well, disease can progress. It is thus important to develop therapeutic approaches that directly protect RGCs in an IOP-independent manner. Compromised nicotinamide adenine dinucleotide (NAD+) metabolism occurs in neurodegenerative diseases, including models of glaucoma. Here we report testing the protective effects of prophylactically systemically administered nicotinamide riboside (NR), a NAD+ precursor, in a mouse model of acute RGC damage (optic nerve crush (ONC)), and in a chronic model of RGC degeneration (ocular hypertension induced by intracameral injection of microbeads). For both models, treatment enhanced RGC survival, assessed by counting cells in retinal flatmounts immunostained for Brn3a+. In the ONC model, treatment preserved RGC function, as assessed by pattern electroretinogram, and suppressed retinal inflammation, as assessed by immunofluorescence staining of retinal fixed sections for glial fibrillary acidic protein (GFAP). This is the first study to demonstrate that systemic treatment with NR is protective in acute and chronic models of RGC damage. The protection is significant and, considering that NR is highly bioavailable in and well-tolerated by humans, may support the proposition of prospective human subject studies.
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14
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Wang J, Struebing FL, Geisert EE. Commonalities of optic nerve injury and glaucoma-induced neurodegeneration: Insights from transcriptome-wide studies. Exp Eye Res 2021; 207:108571. [PMID: 33844961 PMCID: PMC9890784 DOI: 10.1016/j.exer.2021.108571] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 03/28/2021] [Accepted: 04/02/2021] [Indexed: 02/03/2023]
Abstract
Glaucoma is a collection of diseases that lead to an irreversible vision loss due to damage of retinal ganglion cells (RGCs). Although the underlying events leading to RGC death are not fully understood, recent research efforts are beginning to define the genetic changes that play a critical role in the initiation and progression of glaucomatous injury and RGC death. Several genetic and experimental animal models have been developed to mimic glaucomatous neurodegeneration. These models differ in many respects but all result in the loss of RGCs. Assessing transcriptional changes across different models could provide a more complete perspective on the molecular drivers of RGC degeneration. For the past several decades, changes in the retinal transcriptome during neurodegeneration process were defined using microarray methods, RNA sequencing and now single cell RNA sequencing. It is understood that these methods have strengths and weaknesses due to technical differences and variations in the analytical tools used. In this review, we focus on the use of transcriptome-wide expression profiling of the changes occurring as RGCs are lost across different glaucoma models. Commonalities of optic nerve crush and glaucoma-induced neurodegeneration are identified and discussed.
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Affiliation(s)
- Jiaxing Wang
- Emory Eye Center, Department of Ophthalmology, Emory University, 1365B Clifton Road NE, Atlanta, GA, 30322, USA
| | - Felix L. Struebing
- Center for Neuropathology and Prion Research, Ludwig Maximilian University of Munich, Germany,Department for Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Eldon E. Geisert
- Emory Eye Center, Department of Ophthalmology, Emory University, 1365B Clifton Road NE, Atlanta, GA, 30322, USA,Corresponding author: (E.E. Geisert)
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15
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Chen AM, Azar SS, Harris A, Brecha NC, Pérez de Sevilla Müller L. PTEN Expression Regulates Gap Junction Connectivity in the Retina. Front Neuroanat 2021; 15:629244. [PMID: 34093139 PMCID: PMC8172595 DOI: 10.3389/fnana.2021.629244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 04/26/2021] [Indexed: 12/16/2022] Open
Abstract
Manipulation of the phosphatase and tensin homolog (PTEN) pathway has been suggested as a therapeutic approach to treat or prevent vision loss due to retinal disease. In this study, we investigated the effects of deleting one copy of Pten in a well-characterized class of retinal ganglion cells called α-ganglion cells in the mouse retina. In Pten +/- retinas, α-ganglion cells did not exhibit major changes in their dendritic structure, although most cells developed a few, unusual loop-forming dendrites. By contrast, α-ganglion cells exhibited a significant decrease in heterologous and homologous gap junction mediated cell coupling with other retinal ganglion and amacrine cells. Additionally, the majority of OFF α-ganglion cells (12/18 cells) formed novel coupling to displaced amacrine cells. The number of connexin36 puncta, the predominant connexin that mediates gap junction communication at electrical synapses, was decreased by at least 50% on OFF α-ganglion cells. Reduced and incorrect gap junction connectivity of α-ganglion cells will affect their functional properties and alter visual image processing in the retina. The anomalous connectivity of retinal ganglion cells would potentially limit future therapeutic approaches involving manipulation of the Pten pathway for treating ganglion cell degeneration in diseases like glaucoma, traumatic brain injury, Parkinson's, and Alzheimer's diseases.
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Affiliation(s)
- Ashley M. Chen
- Department of Neurobiology, David Geffen School of Medicine at Los Angeles, University of California, Los Angeles, Los Angeles, CA, United States
| | - Shaghauyegh S. Azar
- Department of Neurobiology, David Geffen School of Medicine at Los Angeles, University of California, Los Angeles, Los Angeles, CA, United States
| | - Alexander Harris
- Department of Neurobiology, David Geffen School of Medicine at Los Angeles, University of California, Los Angeles, Los Angeles, CA, United States
| | - Nicholas C. Brecha
- Department of Neurobiology, David Geffen School of Medicine at Los Angeles, University of California, Los Angeles, Los Angeles, CA, United States
- Stein Eye Institute, David Geffen School of Medicine at Los Angeles, University of California, Los Angeles, Los Angeles, CA, United States
- CURE Digestive Diseases Research Center, David Geffen School of Medicine at Los Angeles, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Administration Greater Los Angeles Health System, Los Angeles, CA, United States
| | - Luis Pérez de Sevilla Müller
- Department of Neurobiology, David Geffen School of Medicine at Los Angeles, University of California, Los Angeles, Los Angeles, CA, United States
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16
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Chen P, Wang C, Lin D, Li B, Ye S, Qu J, Wang W. Identification of Slc6a19os and SOX11 as Two Novel Essential Genes in Neuropathic Pain Using Integrated Bioinformatic Analysis and Experimental Verification. Front Neurosci 2021; 15:627945. [PMID: 33584192 PMCID: PMC7876402 DOI: 10.3389/fnins.2021.627945] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 01/04/2021] [Indexed: 12/25/2022] Open
Abstract
The aim of this study was to identify critical genes associated with neuropathic pain. We also used the competing endogenous RNA (ceRNA) hypothesis to identify related long non-coding RNAs (lncRNAs) and messenger RNAs (miRNAs) with potential regulatory roles. We downloaded GSE107180 from the Gene Expression Omnibus database, screened differentially expressed genes (DEGs) using R software, performed comprehensive bioinformatic analyses, and validated the expression of lncRNA Slc6a19os, miR-125a-5p, miR-125b-5p, miR-351-5p, and Sox11 by qRT-PCR and Western blots. We identified 620 DEGs in spared nerve injury (SNI) mice compared with sham (control) mice, including 309 mRNAs and 311 non-coding RNAs. The up-regulated mRNAs were enriched primarily in several inflammation-related GO biological processes and KEGG signaling pathways. A ceRNA network was constructed that included 82 mRNAs, 4 miRNAs, and 2 lnRNAs. An ingenuity pathway analysis (IPA)-based interaction network for mRNAs differentially expressed in the ceRNA identified several biological processes, including "cellular development, connective tissue development and function, tissue development." Compared with sham mice, lncRNA Slc6a19os and Sox11 expression were significantly up-regulated in dorsal root ganglion (DRG) samples from SNI mice detected using qRT-PCR and Western blots (P < 0.05). MiR-125a-5p, miR-125b-5p, and miR-351-5p expression were down-regulated in DRG samples from SNI mice detected using qRT-PCR (P < 0.05). We concluded that Sox11 and lncRNA Slc6a19os were novel essential genes in the pathogenesis and progression of neuropathic pain and speculated that these two genes were regulated by miR-125a-5p, miR-125b-5p, and miR-351-5p.
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Affiliation(s)
- Peng Chen
- Basic Medical School, Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Chen Wang
- First Clinical Medical School, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Dongsheng Lin
- First Clinical Medical School, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Bing Li
- School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Shuai Ye
- School of Life Sciences, East China Normal University, Shanghai, China
| | - Jinglian Qu
- Basic Medical School, Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Wenjing Wang
- Basic Medical School, Guizhou University of Traditional Chinese Medicine, Guiyang, China
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17
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Chen J, Zhang L, Liu L, Yang X, Wu F, Gan X, Zhang R, He Y, Lv Q, Fu H, Zhou L, Zhang J, Liu A, Liu X, Miao L. Acupuncture Treatment Reverses Retinal Gene Expression Induced by Optic Nerve Injury via RNA Sequencing Analysis. Front Integr Neurosci 2019; 13:59. [PMID: 31680887 PMCID: PMC6808026 DOI: 10.3389/fnint.2019.00059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 09/24/2019] [Indexed: 12/02/2022] Open
Abstract
Glaucoma and traumatic optic nerve crush (ONC) injury result in progressive loss of retinal ganglion cells (RGCs) and defects in visual function. In clinical trials of Traditional Chinese Medicine, acupuncture has been widely used for the treatment of ocular diseases. However, the molecular mechanisms of acupuncture treatment are still unclear. In this study, we used technique of RNA sequencing (RNA-seq) to study the effects of acupuncture treatment on retinal transcriptome after axotomy injury. RNA-seq results revealed that 436 genes including 31 transcription factors (TFs) were changed after injury, among them were many well-known neural degeneration related TFs such as Jun, Ddit3, Atf3, and Atf4. Interestingly, acupuncture treatment at acupoint GB20 (Fengchi) significantly reversed a series of differential expressed genes (DEGs) induced by optic nerve injury. While treatments at BL1 (Jingming) or GB20 sham control acupoint-GV16 (Fengfu), led to limited DEG reversal. In contrast, treatments at these two sites further enhanced the trend of DEG expression induced by axotomy injury. At last, retina immunostaining results revealed that only GB20 acupoint treatment increased RGC survival, in consistent with RNA-seq results. Therefore, our study first reported that acupuncture treatment regulated retinal transcriptome and reversed the gene expression induced by axotomy injury, and GB20 acupoint treatment increased RGC survival, which will provide novel therapeutic targets for treatment of ocular diseases.
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Affiliation(s)
- Jie Chen
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Li Zhang
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Lanying Liu
- The Third Affiliated Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Xueqin Yang
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Fengzhi Wu
- Journal Center, Beijing University of Chinese Medicine, Beijing, China
| | - Xiulun Gan
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Rong Zhang
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Yinjia He
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Qiuyi Lv
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Haonan Fu
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Ling Zhou
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Jiaxi Zhang
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Anming Liu
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Xiaodong Liu
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Linqing Miao
- Beijing Advanced Innovation Center for Intelligent Robots and Systems, Beijing Institute of Technology, Beijing, China
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18
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Kang LH, Zhang S, Jiang S, Hu N. Activation of autophagy in the retina after optic nerve crush injury in rats. Int J Ophthalmol 2019; 12:1395-1401. [PMID: 31544032 DOI: 10.18240/ijo.2019.09.04] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 07/24/2019] [Indexed: 12/19/2022] Open
Abstract
AIM To investigate the activation of autophagy in rat retina after optic nerve crush (ONC) and evaluate its relationship with apoptosis of retinal ganglion cells (RGCs). METHODS The ONC model was established. Western blots were performed to investigate expression of p62, LC3 and Beclin-1. Transmission electron microscopy was performed to discover the autophagosomes in the retina after ONC. Immunohistochemistry was used to confirm the distribution of LC3. TUNEL was performed to confirm the relationship between autophagy and RGC apoptosis. RESULTS p62/Beclin-1 ratio was declined shortly after ONC until to day 7 after ONC and then restored to a normal level at day 21. There was an opposite change in the LC3-II/LC3I ratio in the retina compared to the p62/Beclin-1 ratio. Increased autophagosomes were found after ONC using transmission electron microscopy, and most of the LC3-stained cells were colocalized with RGCs and Müller cells. More LC3-immunoreactive cells and apoptotic RGCs were found on day 7 following ONC. CONCLUSION Possible activation of autophagy in RGCs after ONC; autophagy mainly occurred in RGCs and Müller cells, and the apoptosis of RGCs after ONC may be partly associated with autophagic activation.
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Affiliation(s)
- Li-Hua Kang
- Eye Institute, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province, China
| | - Su Zhang
- Nanjing Medical University Affiliated Eye Hospital, Nanjing 210000, Jiangsu Province, China
| | - Sheng Jiang
- Eye Institute, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province, China
| | - Nan Hu
- Eye Institute, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province, China
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19
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Teotia P, Van Hook MJ, Fischer D, Ahmad I. Human retinal ganglion cell axon regeneration by recapitulating developmental mechanisms: effects of recruitment of the mTOR pathway. Development 2019; 146:dev178012. [PMID: 31273087 PMCID: PMC6633601 DOI: 10.1242/dev.178012] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 05/15/2019] [Indexed: 12/15/2022]
Abstract
The poor axon regeneration in the central nervous system (CNS) often leads to permanent functional deficit following disease or injury. For example, degeneration of retinal ganglion cell (RGC) axons in glaucoma leads to irreversible loss of vision. Here, we have tested the hypothesis that the mTOR pathway regulates the development of human RGCs and that its recruitment after injury facilitates axon regeneration. We observed that the mTOR pathway is active during RGC differentiation, and using the induced pluripotent stem cell model of neurogenesis show that it facilitates the differentiation, function and neuritogenesis of human RGCs. Using a microfluidic model, we demonstrate that recruitment of the mTOR pathway facilitates human RGC axon regeneration after axotomy, providing evidence that the recapitulation of developmental mechanism(s) might be a viable approach for facilitating axon regeneration in the diseased or injured human CNS, thus helping to reduce and/or recover loss of function.
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Affiliation(s)
- Pooja Teotia
- Department of Ophthalmology and Visual Science, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Matthew J Van Hook
- Department of Ophthalmology and Visual Science, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Dietmar Fischer
- Department of Cell Physiology, Ruhr University of Bochum, Universitätsstraße 150, 44780 Bochum, Germany
- Division of Experimental Neurology, Medical Faculty, Heinrich Heine University, Merowingerplatz 1a, 40225 Düsseldorf, Germany
| | - Iqbal Ahmad
- Department of Ophthalmology and Visual Science, University of Nebraska Medical Center, Omaha, NE 68198, USA
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