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Scarabosio A, Surico PL, Tereshenko V, Singh RB, Salati C, Spadea L, Caputo G, Parodi PC, Gagliano C, Winograd JM, Zeppieri M. Whole-eye transplantation: Current challenges and future perspectives. World J Transplant 2024; 14:95009. [PMID: 38947970 PMCID: PMC11212585 DOI: 10.5500/wjt.v14.i2.95009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 04/24/2024] [Accepted: 05/15/2024] [Indexed: 06/13/2024] Open
Abstract
Whole-eye transplantation emerges as a frontier in ophthalmology, promising a transformative approach to irreversible blindness. Despite advancements, formidable challenges persist. Preservation of donor eye viability post-enucleation necessitates meticulous surgical techniques to optimize retinal integrity and ganglion cell survival. Overcoming the inhibitory milieu of the central nervous system for successful optic nerve regeneration remains elusive, prompting the exploration of neurotrophic support and immunomodulatory interventions. Immunological tolerance, paramount for graft acceptance, confronts the distinctive immunogenicity of ocular tissues, driving research into targeted immunosuppression strategies. Ethical and legal considerations underscore the necessity for stringent standards and ethical frameworks. Interdisciplinary collaboration and ongoing research endeavors are imperative to navigate these complexities. Biomaterials, stem cell therapies, and precision immunomodulation represent promising avenues in this pursuit. Ultimately, the aim of this review is to critically assess the current landscape of whole-eye transplantation, elucidating the challenges and advancements while delineating future directions for research and clinical practice. Through concerted efforts, whole-eye transplantation stands to revolutionize ophthalmic care, offering hope for restored vision and enhanced quality of life for those afflicted with blindness.
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Affiliation(s)
- Anna Scarabosio
- Department of Plastic Surgery, University Hospital of Udine, Udine 33100, Italy
- Department of Plastic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, United States
| | - Pier Luigi Surico
- Schepens Eye Research Institute of Mass Eye and Ear, Harvard Medical School, Boston, MA 02114, United States
| | - Vlad Tereshenko
- Department of Plastic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, United States
| | - Rohan Bir Singh
- Schepens Eye Research Institute of Mass Eye and Ear, Harvard Medical School, Boston, MA 02114, United States
| | - Carlo Salati
- Department of Ophthalmology, University Hospital of Udine, Udine 33100, Italy
| | - Leopoldo Spadea
- Eye Clinic, Policlinico Umberto I, "Sapienza" University of Rome, Rome 00142, Italy
| | - Glenda Caputo
- Department of Plastic Surgery, University Hospital of Udine, Udine 33100, Italy
| | - Pier Camillo Parodi
- Department of Plastic Surgery, University Hospital of Udine, Udine 33100, Italy
| | - Caterina Gagliano
- Department of Medicine and Surgery, University of Enna "Kore", Enna 94100, Italy
- Eye Clinic Catania University San Marco Hospital, Viale Carlo Azeglio Ciampi 95121 Catania, Italy
| | - Jonathan M Winograd
- Department of Plastic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, United States
| | - Marco Zeppieri
- Department of Ophthalmology, University Hospital of Udine, Udine 33100, Italy
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Sharif NA. Electrical, Electromagnetic, Ultrasound Wave Therapies, and Electronic Implants for Neuronal Rejuvenation, Neuroprotection, Axonal Regeneration, and IOP Reduction. J Ocul Pharmacol Ther 2023; 39:477-498. [PMID: 36126293 DOI: 10.1089/jop.2022.0046] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The peripheral nervous system (PNS) of mammals and nervous systems of lower organisms possess significant regenerative potential. In contrast, although neural plasticity can provide some compensation, the central nervous system (CNS) neurons and nerves of adult mammals generally fail to regenerate after an injury or damage. However, use of diverse electrical, electromagnetic and sonographic energy waves are illuminating novel ways to stimulate neuronal differentiation, proliferation, neurite growth, and axonal elongation/regeneration leading to various levels of functional recovery in animals and humans afflicted with disorders of the CNS, PNS, retina, and optic nerve. Tools such as acupuncture, electroacupuncture, electroshock therapy, electrical stimulation, transcranial magnetic stimulation, red light therapy, and low-intensity pulsed ultrasound therapy are demonstrating efficacy in treating many different maladies. These include wound healing, partial recovery from motor dysfunctions, recovery from ischemic/reperfusion insults and CNS and ocular remyelination, retinal ganglion cell (RGC) rejuvenation, and RGC axonal regeneration. Neural rejuvenation and axonal growth/regeneration processes involve activation or intensifying of the intrinsic bioelectric waves (action potentials) that exist in every neuronal circuit of the body. In addition, reparative factors released at the nerve terminals and via neuronal dendrites (transmitter substances), extracellular vesicles containing microRNAs and neurotrophins, and intercellular communication occurring via nanotubes aid in reestablishing lost or damaged connections between the traumatized tissues and the PNS and CNS. Many other beneficial effects of the aforementioned treatment paradigms are mediated via gene expression alterations such as downregulation of inflammatory and death-signal genes and upregulation of neuroprotective and cytoprotective genes. These varied techniques and technologies will be described and discussed covering cell-based and animal model-based studies. Data from clinical applications and linkage to human ocular diseases will also be discussed where relevant translational research has been reported.
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Affiliation(s)
- Najam A Sharif
- Global Alliances and External Research, Ophthalmology Innovation Center, Santen Inc., Emeryville, California, USA
- Singapore Eye Research Institute (SERI), Singapore
- SingHealth Duke-NUS Ophthalmology and Visual Sciences Academic Clinical Programme, Duke-National University of Singapore Medical School, Singapore
- Department of Surgery and Cancer, Imperial College of Science and Technology, London, United Kingdom
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Texas Southern University, Houston, Texas, USA
- Department of Pharmacology and Neuroscience, University of North Texas Health Sciences Center, Fort Worth, Texas, USA
- Department of Pharmacy Sciences, Creighton University, Omaha, Nebraska, USA
- Insitute of Ophthalmology, University College London (UCL), London, United Kingdom
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Zhang ZY, Zuo ZY, Liang Y, Zhang SM, Zhang CX, Chi J, Fan B, Li GY. Promotion of axon regeneration and protection on injured retinal ganglion cells by rCXCL2. Inflamm Regen 2023; 43:31. [PMID: 37340465 DOI: 10.1186/s41232-023-00283-5] [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: 11/21/2022] [Accepted: 05/31/2023] [Indexed: 06/22/2023] Open
Abstract
BACKGROUND In addition to rescuing injured retinal ganglion cells (RGCs) by stimulating the intrinsic growth ability of damaged RGCs in various retinal/optic neuropathies, increasing evidence has shown that the external microenvironmental factors also play a crucial role in restoring the survival of RGCs by promoting the regrowth of RGC axons, especially inflammatory factors. In this study, we aimed to screen out the underlying inflammatory factor involved in the signaling of staurosporine (STS)-induced axon regeneration and verify its role in the protection of RGCs and the promotion of axon regrowth. METHODS We performed transcriptome RNA sequencing for STS induction models in vitro and analyzed the differentially expressed genes. After targeting the key gene, we verified the role of the candidate factor in RGC protection and promotion of axon regeneration in vivo with two RGC-injured animal models (optic nerve crush, ONC; retinal N-methyl-D-aspartate, NMDA damage) by using cholera toxin subunit B anterograde axon tracing and specific immunostaining of RGCs. RESULTS We found that a series of inflammatory genes expressed upregulated in the signaling of STS-induced axon regrowth and we targeted the candidate CXCL2 gene since the level of the chemokine CXCL2 gene elevated significantly among the top upregulated genes. We further demonstrated that intravitreal injection of rCXCL2 robustly promoted axon regeneration and significantly improved RGC survival in ONC-injured mice in vivo. However, different from its role in ONC model, the intravitreal injection of rCXCL2 was able to simply protect RGCs against NMDA-induced excitotoxicity in mouse retina and maintain the long-distance projection of RGC axons, yet failed to promote significant axon regeneration. CONCLUSIONS We provide the first in vivo evidence that CXCL2, as an inflammatory factor, is a key regulator in the axon regeneration and neuroprotection of RGCs. Our comparative study may facilitate deciphering the exact molecular mechanisms of RGC axon regeneration and developing high-potency targeted drugs.
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Affiliation(s)
- Zi-Yuan Zhang
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China
| | - Zhao-Yang Zuo
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China
| | - Yang Liang
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China
| | - Si-Ming Zhang
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China
| | - Chun-Xia Zhang
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China
| | - Jing Chi
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China
| | - Bin Fan
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China.
| | - Guang-Yu Li
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, 130041, China.
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Agadagba SK, Lim LW, Chan LLH. Advances in transcorneal electrical stimulation: From the eye to the brain. Front Cell Neurosci 2023; 17:1134857. [PMID: 36937185 PMCID: PMC10019785 DOI: 10.3389/fncel.2023.1134857] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 02/07/2023] [Indexed: 03/06/2023] Open
Abstract
The mammalian brain is reported to contain about 106-109 neurons linked together to form complex networks. Physiologically, the neuronal networks interact in a rhythmic oscillatory pattern to coordinate the brain's functions. Neuromodulation covers a broad range of techniques that can alter neuronal network activity through the targeted delivery of electrical or chemical stimuli. Neuromodulation can be used to potentially treat medical conditions and can serve as a research tool for studying neural functions. Typically, the main method of neuromodulation is to electrically stimulate specific structures in both the central and peripheral nervous systems via surgically implanted electrodes. Therefore, it is imperative to explore novel and safer methods for altering neuronal network activity. Transcorneal electrical stimulation (TES) has rapidly emerged as a non-invasive neuromodulatory technique that can exert beneficial effects on the brain through the eyes. There is substantial evidence to show that TES can change the brain oscillations in rodents. Moreover, the molecular data clearly shows that TES can also activate non-visual brain regions. In this review, we first summarize the use of TES in the retina and then discuss its effects in the brain through the eye-brain connection. We then comprehensively review the substantial evidence from electrophysiological, behavioral, and molecular studies on the role of TES on modulating neurons in the brain. Lastly, we discuss the implications and possible future directions of the research on TES as a non-invasive tool for neuromodulation of the brain via directly stimulating the mammalian eye.
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Affiliation(s)
| | - Lee Wei Lim
- Neuromodulation Laboratory, School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Leanne Lai Hang Chan
- Department of Electrical Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong SAR, China
- *Correspondence: Leanne Lai Hang Chan
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Xu K, Yu L, Wang Z, Lin P, Zhang N, Xing Y, Yang N. Use of gene therapy for optic nerve protection: Current concepts. Front Neurosci 2023; 17:1158030. [PMID: 37090805 PMCID: PMC10117674 DOI: 10.3389/fnins.2023.1158030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 03/20/2023] [Indexed: 04/25/2023] Open
Abstract
Gene therapy has become an essential treatment for optic nerve injury (ONI) in recent years, and great strides have been made using animal models. ONI, which is characterized by the loss of retinal ganglion cells (RGCs) and axons, can induce abnormalities in the pupil light reflex, visual field defects, and even vision loss. The eye is a natural organ to target with gene therapy because of its high accessibility and certain immune privilege. As such, numerous gene therapy trials are underway for treating eye diseases such as glaucoma. The aim of this review was to cover research progress made in gene therapy for ONI. Specifically, we focus on the potential of gene therapy to prevent the progression of neurodegenerative diseases and protect both RGCs and axons. We cover the basic information of gene therapy, including the classification of gene therapy, especially focusing on genome editing therapy, and then we introduce common editing tools and vector tools such as Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) -Cas9 and adeno-associated virus (AAV). We also summarize the progress made on understanding the roles of brain derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), phosphatase-tensin homolog (PTEN), suppressor of cytokine signal transduction 3 (SOCS3), histone acetyltransferases (HATs), and other important molecules in optic nerve protection. However, gene therapy still has many challenges, such as misalignment and mutations, immunogenicity of AAV, time it takes and economic cost involved, which means that these issues need to be addressed before clinical trials can be considered.
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Affiliation(s)
- Kexin Xu
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Lu Yu
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
- Department of Ophthalmology, Aier Eye Hospital of Wuhan University, Wuhan, Hubei, China
| | - Zhiyi Wang
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Pei Lin
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Ningzhi Zhang
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Yiqiao Xing
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
- Department of Ophthalmology, Aier Eye Hospital of Wuhan University, Wuhan, Hubei, China
- *Correspondence: Yiqiao Xing,
| | - Ning Yang
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
- Ning Yang,
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Vanhunsel S, Bergmans S, Beckers A, Etienne I, Van Bergen T, De Groef L, Moons L. The age factor in optic nerve regeneration: Intrinsic and extrinsic barriers hinder successful recovery in the short-living killifish. Aging Cell 2022; 21:e13537. [PMID: 34927348 PMCID: PMC8761009 DOI: 10.1111/acel.13537] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 11/24/2021] [Accepted: 12/03/2021] [Indexed: 01/06/2023] Open
Abstract
As the mammalian central nervous system matures, its regenerative ability decreases, leading to incomplete or non-recovery from the neurodegenerative diseases and central nervous system insults that we are increasingly facing in our aging world population. Current neuroregenerative research is largely directed toward identifying the molecular and cellular players that underlie central nervous system repair, yet it repeatedly ignores the aging context in which many of these diseases appear. Using an optic nerve crush model in a novel biogerontology model, that is, the short-living African turquoise killifish, the impact of aging on injury-induced optic nerve repair was investigated. This work reveals an age-related decline in axonal regeneration in female killifish, with different phases of the repair process being affected depending on the age. Interestingly, as in mammals, both a reduced intrinsic growth potential and a non-supportive cellular environment seem to lie at the basis of this impairment. Overall, we introduce the killifish visual system and its age-dependent regenerative ability as a model to identify new targets for neurorepair in non-regenerating individuals, thereby also considering the effects of aging on neurorepair.
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Affiliation(s)
- Sophie Vanhunsel
- Neural Circuit Development and Regeneration Research GroupAnimal Physiology and Neurobiology SectionDepartment of BiologyKU LeuvenLeuvenBelgium
| | - Steven Bergmans
- Neural Circuit Development and Regeneration Research GroupAnimal Physiology and Neurobiology SectionDepartment of BiologyKU LeuvenLeuvenBelgium
| | - An Beckers
- Neural Circuit Development and Regeneration Research GroupAnimal Physiology and Neurobiology SectionDepartment of BiologyKU LeuvenLeuvenBelgium
| | | | | | - Lies De Groef
- Neural Circuit Development and Regeneration Research GroupAnimal Physiology and Neurobiology SectionDepartment of BiologyKU LeuvenLeuvenBelgium
- Leuven Brain InstituteLeuvenBelgium
| | - Lieve Moons
- Neural Circuit Development and Regeneration Research GroupAnimal Physiology and Neurobiology SectionDepartment of BiologyKU LeuvenLeuvenBelgium
- Leuven Brain InstituteLeuvenBelgium
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7
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Peterson SL, Li Y, Sun CJ, Wong KA, Leung KS, de Lima S, Hanovice NJ, Yuki K, Stevens B, Benowitz LI. Retinal Ganglion Cell Axon Regeneration Requires Complement and Myeloid Cell Activity within the Optic Nerve. J Neurosci 2021; 41:8508-8531. [PMID: 34417332 PMCID: PMC8513703 DOI: 10.1523/jneurosci.0555-21.2021] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 07/21/2021] [Accepted: 08/16/2021] [Indexed: 01/01/2023] Open
Abstract
Axon regenerative failure in the mature CNS contributes to functional deficits following many traumatic injuries, ischemic injuries, and neurodegenerative diseases. The complement cascade of the innate immune system responds to pathogen threat through inflammatory cell activation, pathogen opsonization, and pathogen lysis, and complement is also involved in CNS development, neuroplasticity, injury, and disease. Here, we investigated the involvement of the classical complement cascade and microglia/monocytes in CNS repair using the mouse optic nerve injury (ONI) model, in which axons arising from retinal ganglion cells (RGCs) are disrupted. We report that central complement C3 protein and mRNA, classical complement C1q protein and mRNA, and microglia/monocyte phagocytic complement receptor CR3 all increase in response to ONI, especially within the optic nerve itself. Importantly, genetic deletion of C1q, C3, or CR3 attenuates RGC axon regeneration induced by several distinct methods, with minimal effects on RGC survival. Local injections of C1q function-blocking antibody revealed that complement acts primarily within the optic nerve, not retina, to support regeneration. Moreover, C1q opsonizes and CR3+ microglia/monocytes phagocytose growth-inhibitory myelin debris after ONI, a likely mechanism through which complement and myeloid cells support axon regeneration. Collectively, these results indicate that local optic nerve complement-myeloid phagocytic signaling is required for CNS axon regrowth, emphasizing the axonal compartment and highlighting a beneficial neuroimmune role for complement and microglia/monocytes in CNS repair.SIGNIFICANCE STATEMENT Despite the importance of achieving axon regeneration after CNS injury and the inevitability of inflammation after such injury, the contributions of complement and microglia to CNS axon regeneration are largely unknown. Whereas inflammation is commonly thought to exacerbate the effects of CNS injury, we find that complement proteins C1q and C3 and microglia/monocyte phagocytic complement receptor CR3 are each required for retinal ganglion cell axon regeneration through the injured mouse optic nerve. Also, whereas studies of optic nerve regeneration generally focus on the retina, we show that the regeneration-relevant role of complement and microglia/monocytes likely involves myelin phagocytosis within the optic nerve. Thus, our results point to the importance of the innate immune response for CNS repair.
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Affiliation(s)
- Sheri L Peterson
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
| | - Yiqing Li
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong China, 510060
| | - Christina J Sun
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
| | - Kimberly A Wong
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
| | - Kylie S Leung
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
| | - Silmara de Lima
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
| | - Nicholas J Hanovice
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
| | - Kenya Yuki
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
| | - Beth Stevens
- F.M. Kirby Neurobiology Center, and
- Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02142
| | - Larry I Benowitz
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02115
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8
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Sergeeva EG, Rosenberg PA, Benowitz LI. Non-Cell-Autonomous Regulation of Optic Nerve Regeneration by Amacrine Cells. Front Cell Neurosci 2021; 15:666798. [PMID: 33935656 PMCID: PMC8085350 DOI: 10.3389/fncel.2021.666798] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 03/19/2021] [Indexed: 11/13/2022] Open
Abstract
Visual information is conveyed from the eye to the brain through the axons of retinal ganglion cells (RGCs) that course through the optic nerve and synapse onto neurons in multiple subcortical visual relay areas. RGCs cannot regenerate their axons once they are damaged, similar to most mature neurons in the central nervous system (CNS), and soon undergo cell death. These phenomena of neurodegeneration and regenerative failure are widely viewed as being determined by cell-intrinsic mechanisms within RGCs or to be influenced by the extracellular environment, including glial or inflammatory cells. However, a new concept is emerging that the death or survival of RGCs and their ability to regenerate axons are also influenced by the complex circuitry of the retina and that the activation of a multicellular signaling cascade involving changes in inhibitory interneurons - the amacrine cells (AC) - contributes to the fate of RGCs. Here, we review our current understanding of the role that interneurons play in cell survival and axon regeneration after optic nerve injury.
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Affiliation(s)
- Elena G. Sergeeva
- Department of Neurology, Boston Children’s Hospital, Boston, MA, United States
- Kirby Center for Neuroscience, Boston Children’s Hospital, Boston, MA, United States
- Department of Neurology, Harvard Medical School, Boston, MA, United States
| | - Paul A. Rosenberg
- Department of Neurology, Boston Children’s Hospital, Boston, MA, United States
- Kirby Center for Neuroscience, Boston Children’s Hospital, Boston, MA, United States
- Department of Neurology, Harvard Medical School, Boston, MA, United States
| | - Larry I. Benowitz
- Kirby Center for Neuroscience, Boston Children’s Hospital, Boston, MA, United States
- Laboratories for Neuroscience Research in Neurosurgery, Boston Children’s Hospital, Boston, MA, United States
- Department of Neurosurgery, Boston Children’s Hospital, Boston, MA, United States
- Department of Neurosurgery, Harvard Medical School, Boston, MA, United States
- Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
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9
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Intravitreal Co-Administration of GDNF and CNTF Confers Synergistic and Long-Lasting Protection against Injury-Induced Cell Death of Retinal Ganglion Cells in Mice. Cells 2020; 9:cells9092082. [PMID: 32932933 PMCID: PMC7565883 DOI: 10.3390/cells9092082] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 09/03/2020] [Accepted: 09/09/2020] [Indexed: 12/15/2022] Open
Abstract
We have recently demonstrated that neural stem cell-based intravitreal co-administration of glial cell line-derived neurotrophic factor (GDNF) and ciliary neurotrophic factor (CNTF) confers profound protection to injured retinal ganglion cells (RGCs) in a mouse optic nerve crush model, resulting in the survival of ~38% RGCs two months after the nerve lesion. Here, we analyzed whether this neuroprotective effect is long-lasting and studied the impact of the pronounced RGC rescue on axonal regeneration. To this aim, we co-injected a GDNF- and a CNTF-overexpressing neural stem cell line into the vitreous cavity of adult mice one day after an optic nerve crush and determined the number of surviving RGCs 4, 6 and 8 months after the lesion. Remarkably, we found no significant decrease in the number of surviving RGCs between the successive analysis time points, indicating that the combined administration of GDNF and CNTF conferred lifelong protection to injured RGCs. While the simultaneous administration of GDNF and CNTF stimulated pronounced intraretinal axon growth when compared to retinas treated with either factor alone, numbers of regenerating axons in the distal optic nerve stumps were similar in animals co-treated with both factors and animals treated with CNTF only.
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10
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Antal A, Sabel B. Low vision: Rescue, regeneration, restoration and rehabilitation. Restor Neurol Neurosci 2020; 37:523-524. [PMID: 31839617 DOI: 10.3233/rnn-199001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
| | - Bernhard Sabel
- Institute of Medical Psychology, Otto-v.-Guericke University of Magdeburg, Magdeburg, Germany
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11
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Sabel BA, Gao Y, Antal A. Reversibility of visual field defects through induction of brain plasticity: vision restoration, recovery and rehabilitation using alternating current stimulation. Neural Regen Res 2020; 15:1799-1806. [PMID: 32246620 PMCID: PMC7513964 DOI: 10.4103/1673-5374.280302] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
For decades visual field defects were considered irreversible because it was thought that in the visual system the regeneration potential of the neuronal tissues is low. Nevertheless, there is always some potential for partial recovery of the visual field defect that can be achieved through induction of neuroplasticity. Neuroplasticity refers to the ability of the brain to change its own functional architecture by modulating synaptic efficacy. It is maintained throughout life and just as neurological rehabilitation can improve motor coordination, visual field defects in glaucoma, diabetic retinopathy or optic neuropathy can be improved by inducing neuroplasticity. In ophthalmology many new treatment paradigms have been tested that can induce neuroplastic changes, including non-invasive alternating current stimulation. Treatment with alternating current stimulation (e.g., 30 minutes, daily for 10 days using transorbital electrodes and ~10 Hz) activates the entire retina and parts of the brain. Electroencephalography and functional magnetic resonance imaging studies revealed local activation of the visual cortex, global reorganization of functional brain networks, and enhanced blood flow, which together activate neurons and their networks. The future of low vision is optimistic because vision loss is indeed, partially reversible.
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Affiliation(s)
- Bernhard A Sabel
- Institute of Medical Psychology, Medical Faculty, Otto-von-Guericke University of Magdeburg; Center for Behavioral and Brain Sciences (CBBS); Sabel Vision Restoration Center, Magdeburg, Germany
| | - Ying Gao
- Sabel Vision Restoration Center, Magdeburg, Germany
| | - Andrea Antal
- Institute of Medical Psychology, Medical Faculty, Otto-von-Guericke University of Magdeburg, Magdeburg; Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, Germany
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