1
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Nheu D, Petratos S. How does Nogo-A signalling influence mitochondrial function during multiple sclerosis pathogenesis? Neurosci Biobehav Rev 2024; 163:105767. [PMID: 38885889 DOI: 10.1016/j.neubiorev.2024.105767] [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: 03/17/2024] [Revised: 05/30/2024] [Accepted: 06/08/2024] [Indexed: 06/20/2024]
Abstract
Multiple sclerosis (MS) is a severe neurological disorder that involves inflammation in the brain, spinal cord and optic nerve with key disabling neuropathological outcomes being axonal damage and demyelination. When degeneration of the axo-glial union occurs, a consequence of inflammatory damage to central nervous system (CNS) myelin, dystrophy and death can lead to large membranous structures from dead oligodendrocytes and degenerative myelin deposited in the extracellular milieu. For the first time, this review covers mitochondrial mechanisms that may be operative during MS-related neurodegenerative changes directly activated during accumulating extracellular deposits of myelin associated inhibitory factors (MAIFs), that include the potent inhibitor of neurite outgrowth, Nogo-A. Axonal damage may occur when Nogo-A binds to and signals through its cognate receptor, NgR1, a multimeric complex, to initially stall axonal transport and limit the delivery of important growth-dependent cargo and subcellular organelles such as mitochondria for metabolic efficiency at sites of axo-glial disintegration as a consequence of inflammation. Metabolic efficiency in axons fails during active demyelination and progressive neurodegeneration, preceded by stalled transport of functional mitochondria to fuel axo-glial integrity.
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Affiliation(s)
- Danica Nheu
- Department of Neuroscience, School of Translational Medicine, Monash University, Prahran, VIC 3004, Australia
| | - Steven Petratos
- Department of Neuroscience, School of Translational Medicine, Monash University, Prahran, VIC 3004, Australia.
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2
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McGuinness HY, Gu W, Shi Y, Kobe B, Ve T. SARM1-Dependent Axon Degeneration: Nucleotide Signaling, Neurodegenerative Disorders, Toxicity, and Therapeutic Opportunities. Neuroscientist 2024; 30:473-492. [PMID: 37002660 PMCID: PMC11282687 DOI: 10.1177/10738584231162508] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
Axons are an essential component of the nervous system, and axon degeneration is an early feature of many neurodegenerative disorders. The NAD+ metabolome plays an essential role in regulating axonal integrity. Axonal levels of NAD+ and its precursor NMN are controlled in large part by the NAD+ synthesizing survival factor NMNAT2 and the pro-neurodegenerative NADase SARM1, whose activation triggers axon destruction. SARM1 has emerged as a promising axon-specific target for therapeutic intervention, and its function, regulation, structure, and role in neurodegenerative diseases have been extensively characterized in recent years. In this review, we first introduce the key molecular players involved in the SARM1-dependent axon degeneration program. Next, we summarize recent major advances in our understanding of how SARM1 is kept inactive in healthy neurons and how it becomes activated in injured or diseased neurons, which has involved important insights from structural biology. Finally, we discuss the role of SARM1 in neurodegenerative disorders and environmental neurotoxicity and its potential as a therapeutic target.
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Affiliation(s)
- Helen Y. McGuinness
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Saint Lucia, Australia
| | - Weixi Gu
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Saint Lucia, Australia
| | - Yun Shi
- Institute for Glycomics, Griffith University, Gold Coast, Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Saint Lucia, Australia
| | - Thomas Ve
- Institute for Glycomics, Griffith University, Gold Coast, Australia
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3
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Geisler S. Augustus Waller's foresight realized: SARM1 in peripheral neuropathies. Curr Opin Neurobiol 2024; 87:102884. [PMID: 38852438 DOI: 10.1016/j.conb.2024.102884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 05/16/2024] [Accepted: 05/17/2024] [Indexed: 06/11/2024]
Abstract
Peripheral neuropathy is a common neurodegenerative condition characterized by numbness, tingling, pain, and weakness that frequently starts in the distal limbs. Arising from multiple etiologies, many peripheral neuropathies exhibit a slowly progressive course due to axon degeneration for which no effective treatments exist. During the past decade, numerous crucial insights into mechanisms of axon degeneration in peripheral neuropathies emerged from experiments involving nerve-cutting procedures, revealing the central role of the SARM1 axon degeneration pathway in both. Here I review commonalities and differences in the role of SARM1 after nerve cut and in several acquired and inherited peripheral neuropathies. This new knowledge now paves the way for the development of therapeutics that directly address root causes of various kinds of neuropathies.
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Affiliation(s)
- Stefanie Geisler
- Department of Neurology, Washington University School of Medicine in St. Louis, 660S. Euclid Ave, Box 8111, St. Louis, MO 63110, USA.
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4
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Ni W, Ye Y, Wang S, Li X, Li H, Cheng D, Jia Q, Liu Z, Shan S, Qiang Y, Chao S, Zhao X, Song F. Pyrrole adducts mediated mitochondrial dysfunction activates SARM1-dependent axon degeneration in 2,5-hexanedione-induced neuropathy. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 360:124651. [PMID: 39094998 DOI: 10.1016/j.envpol.2024.124651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 07/21/2024] [Accepted: 07/30/2024] [Indexed: 08/04/2024]
Abstract
2,5-hexanedione (HD) is the γ-diketone metabolite of industrial organic solvent n-hexane, primarily responsible for n-hexane neurotoxicity. Previous studies have shown that the formation of pyrrole adducts (PAs) is crucial for the toxic axonopathy induced by HD. However, the exact mechanism underlying PAs-induced axonal degeneration remains unclear. Recently, Sterile α and toll/interleukin 1 receptor motif-containing protein 1 (SARM1) has been identified as the central executor of axon degeneration. This study was designed to investigate the role of SARM1-mediated axon degeneration in rats exposed to HD. Furthermore, the causal relationship between PAs and SARM1-mediated axon degeneration was further explored using Sarm1 KO mice. Our findings suggest that HD causes axon degeneration and neuronal loss in animals. Mechanistic studies revealed that HD activates SARM1-dependent axonal degeneration machinery. In contrast, Sarm1 KO attenuates motor dysfunction and rescues neuron loss following HD exposure. Interestingly, the PAs formed by the binding of HD to proteins primarily accumulate on mitochondria, leading to mitochondrial dysfunction. This dysfunction serves as an upstream event in HD-induced nerve injuries. Our findings highlight the crucial role of PAs formation in the major pathological changes during n-hexane poisoning, providing a potential therapeutic target for n-hexane neuropathy.
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Affiliation(s)
- Wenting Ni
- Department of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China; Gansu Provincial Hospital, Lanzhou, Gansu, 730000, China
| | - Yihan Ye
- Department of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Shuai Wang
- Department of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Xianjie Li
- Institute of Biological and Medical Engineering, Guangdong Academy of Sciences, Guangzhou, Guangdong, 510075, China
| | - Hui Li
- Department of Health Test and Detection, Shandong Center for Disease Control and Prevention, Jinan, Shandong, 250014, China
| | - Dong Cheng
- Department of Health Test and Detection, Shandong Center for Disease Control and Prevention, Jinan, Shandong, 250014, China
| | - Qiang Jia
- Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Science, Jinan, Shandong, 250062, China
| | - Zhidan Liu
- Department of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Shulin Shan
- Department of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Yalong Qiang
- Department of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Shihua Chao
- Department of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Xiulan Zhao
- Department of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China
| | - Fuyong Song
- Department of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China.
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5
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Zheng C, Li Y, Wu X, Gao L, Chen X. Advances in the Synthesis and Physiological Metabolic Regulation of Nicotinamide Mononucleotide. Nutrients 2024; 16:2354. [PMID: 39064797 PMCID: PMC11279976 DOI: 10.3390/nu16142354] [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: 06/25/2024] [Revised: 07/18/2024] [Accepted: 07/19/2024] [Indexed: 07/28/2024] Open
Abstract
Nicotinamide mononucleotide (NMN), the direct precursor of nicotinamide adenine dinucleotide (NAD+), is involved in the regulation of many physiological and metabolic reactions in the body. NMN can indirectly affect cellular metabolic pathways, DNA repair, and senescence, while also being essential for maintaining tissues and dynamic metabolic equilibria, promoting healthy aging. Therefore, NMN has found many applications in the food, pharmaceutical, and cosmetics industries. At present, NMN synthesis strategies mainly include chemical synthesis and biosynthesis. Despite its potential benefits, the commercial production of NMN by organic chemistry approaches faces environmental and safety problems. With the rapid development of synthetic biology, it has become possible to construct microbial cell factories to produce NMN in a cost-effective way. In this review, we summarize the chemical and biosynthetic strategies of NMN, offering an overview of the recent research progress on host selection, chassis cell optimization, mining of key enzymes, metabolic engineering, and adaptive fermentation strategies. In addition, we also review the advances in the role of NMN in aging, metabolic diseases, and neural function. This review provides comprehensive technical guidance for the efficient biosynthesis of NMN as well as a theoretical basis for its application in the fields of food, medicine, and cosmetics.
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Affiliation(s)
- Chuxiong Zheng
- School of Biological Engineering, Dalian Polytechnic University, Dalian 116034, China;
| | - Yumeng Li
- National Technology Innovation Center for Synthetic Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin 300308, China; (Y.L.); (X.W.)
| | - Xin Wu
- National Technology Innovation Center for Synthetic Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin 300308, China; (Y.L.); (X.W.)
| | - Le Gao
- National Technology Innovation Center for Synthetic Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin 300308, China; (Y.L.); (X.W.)
| | - Xiaoyi Chen
- School of Biological Engineering, Dalian Polytechnic University, Dalian 116034, China;
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6
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Loreto A, Merlini E, Coleman MP. Programmed axon death: a promising target for treating retinal and optic nerve disorders. Eye (Lond) 2024; 38:1802-1809. [PMID: 38538779 PMCID: PMC11226669 DOI: 10.1038/s41433-024-03025-0] [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: 09/04/2023] [Revised: 02/13/2024] [Accepted: 03/08/2024] [Indexed: 07/07/2024] Open
Abstract
Programmed axon death is a druggable pathway of axon degeneration that has garnered considerable interest from pharmaceutical companies as a promising therapeutic target for various neurodegenerative disorders. In this review, we highlight mechanisms through which this pathway is activated in the retina and optic nerve, and discuss its potential significance for developing therapies for eye disorders and beyond. At the core of programmed axon death are two enzymes, NMNAT2 and SARM1, with pivotal roles in NAD metabolism. Extensive preclinical data in disease models consistently demonstrate remarkable, and in some instances, complete and enduring neuroprotection when this mechanism is targeted. Findings from animal studies are now being substantiated by genetic human data, propelling the field rapidly toward clinical translation. As we approach the clinical phase, the selection of suitable disorders for initial clinical trials targeting programmed axon death becomes crucial for their success. We delve into the multifaceted roles of programmed axon death and NAD metabolism in retinal and optic nerve disorders. We discuss the role of SARM1 beyond axon degeneration, including its potential involvement in neuronal soma death and photoreceptor degeneration. We also discuss genetic human data and environmental triggers of programmed axon death. Lastly, we touch upon potential therapeutic approaches targeting NMNATs and SARM1, as well as the nicotinamide trials for glaucoma. The extensive literature linking programmed axon death to eye disorders, along with the eye's suitability for drug delivery and visual assessments, makes retinal and optic nerve disorders strong contenders for early clinical trials targeting programmed axon death.
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Affiliation(s)
- Andrea Loreto
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, Cambridge, UK.
- School of Medical Sciences and Save Sight Institute, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.
| | - Elisa Merlini
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, Cambridge, UK
| | - Michael P Coleman
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, Cambridge, UK.
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7
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Dingwall CB, Sasaki Y, Strickland A, Summers DW, Bloom AJ, DiAntonio A, Milbrandt J. Suppressing phagocyte activation by overexpressing the phosphatidylserine lipase ABHD12 preserves sarmopathic nerves. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.20.599919. [PMID: 38979309 PMCID: PMC11230269 DOI: 10.1101/2024.06.20.599919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Programmed axon degeneration (AxD) is a key feature of many neurodegenerative diseases. In healthy axons, the axon survival factor NMNAT2 inhibits SARM1, the central executioner of AxD, preventing it from initiating the rapid local NAD+ depletion and metabolic catastrophe that precipitates axon destruction. Because these components of the AxD pathway act within neurons, it was also assumed that the timetable of AxD was set strictly by a cell-intrinsic mechanism independent of neuron-extrinsic processes later activated by axon fragmentation. However, using a rare human disease model of neuropathy caused by hypomorphic NMNAT2 mutations and chronic SARM1 activation (sarmopathy), we demonstrated that neuronal SARM1 can initiate macrophage-mediated axon elimination long before stressed-but-viable axons would otherwise succumb to cell-intrinsic metabolic failure. Investigating potential SARM1-dependent signals that mediate macrophage recognition and/or engulfment of stressed-but-viable axons, we found that chronic SARM1 activation triggers axonal blebbing and dysregulation of phosphatidylserine (PS), a potent phagocyte immunomodulatory molecule. Neuronal expression of the phosphatidylserine lipase ABDH12 suppresses nerve macrophage activation, preserves motor axon integrity, and rescues motor function in this chronic sarmopathy model. We conclude that PS dysregulation is an early SARM1-dependent axonal stress signal, and that blockade of phagocytic recognition and engulfment of stressed-but-viable axons could be an attractive therapeutic target for management of neurological disorders involving SARM1 activation.
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8
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Zhang Y, Yao Y, Yang J, Zhou B, Zhu Y. Inhibiting the SARM1-NAD + axis reduces oxidative stress-induced damage to retinal and nerve cells. Int Immunopharmacol 2024; 134:112193. [PMID: 38723372 DOI: 10.1016/j.intimp.2024.112193] [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: 02/10/2024] [Revised: 04/17/2024] [Accepted: 04/29/2024] [Indexed: 06/03/2024]
Abstract
Retinal neurodegenerative diseases are a category of refractory blinding eye conditions closely associated with oxidative stress induced by mitochondrial dysfunction in retinal cells. SARM1, a core driver molecule leading to axonal degeneration, possesses NAD+ enzyme (NADase) activity. However, the role of the SARM1-NAD+ axis in oxidative stress-induced retinal cell death remains unclear. Here, we employed the SARM1 NADase inhibitor DSRM-3716 and established a glucose oxidase (GOx)-induced oxidative stress cell model. We found that compared to the GOx group, the DSRM-3716 pre-treated group reduced the hydrolysis of NAD+, inhibited the elevation of oxidative stress markers induced by GOx, decreased mitochondrial dysfunction, lowered the phosphorylation level of JNK, and attenuated the occurrence of pyroptosis in retinal and nerve cells, thereby providing protection for neurite growth. Further utilization of the JNK activator Anisomycin activated JNK, revealed that the JNK/c-Jun pathway down-regulated NMNAT2 expression. Consequently, it reduced cellular NAD+ synthesis, exacerbated mitochondrial dysfunction and cell pyroptosis, and reversed the protective effect of DSRM-3716 on cells. In summary, the inhibition of SARM1 NADase activity substantially mitigates oxidative damage to retinal cells and mitochondrial damage. Additionally, JNK simultaneously serves as both an upstream and downstream regulator in the SARM1-NAD+ axis, regulating retinal cell pyroptosis and neurite injury. Thus, this study provides new insights into the pathological processes of retinal cell oxidative stress and identifies potential therapeutic targets for retinal neurodegenerative diseases.
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Affiliation(s)
- Yannan Zhang
- Department of Ophthalmology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian Province, China; Department of Ophthalmology, National Regional Medical Center, Binghai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China; Fujian Institute of Ophthalmology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China; Fujian Provincial Clinical Medical Research Center of Eye Diseases and Optometry, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Yihua Yao
- Department of Ophthalmology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian Province, China; Department of Ophthalmology, National Regional Medical Center, Binghai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China; Fujian Institute of Ophthalmology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China; Fujian Provincial Clinical Medical Research Center of Eye Diseases and Optometry, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Juhua Yang
- The School of Pharmacy, Fujian Medical University, Fuzhou, Fujian Province, China
| | - Biting Zhou
- Department of Ophthalmology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian Province, China; Department of Ophthalmology, National Regional Medical Center, Binghai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China; Fujian Institute of Ophthalmology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China; Fujian Provincial Clinical Medical Research Center of Eye Diseases and Optometry, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China.
| | - Yihua Zhu
- Department of Ophthalmology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian Province, China; Department of Ophthalmology, National Regional Medical Center, Binghai Campus of the First Affiliated Hospital, Fujian Medical University, Fuzhou, China; Fujian Institute of Ophthalmology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China; Fujian Provincial Clinical Medical Research Center of Eye Diseases and Optometry, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China.
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9
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Hinz FI, Villegas CLM, Roberts JT, Yao H, Gaddam S, Delwig A, Green SA, Fredrickson C, Adrian M, Asuncion RR, Cheung TK, Hayne M, Hackos DH, Rose CM, Richmond D, Hoogenraad CC. Context-Specific Stress Causes Compartmentalized SARM1 Activation and Local Degeneration in Cortical Neurons. J Neurosci 2024; 44:e2424232024. [PMID: 38692735 PMCID: PMC11170950 DOI: 10.1523/jneurosci.2424-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 04/21/2024] [Accepted: 04/23/2024] [Indexed: 05/03/2024] Open
Abstract
Sterile alpha and TIR motif containing 1 (SARM1) is an inducible NADase that localizes to mitochondria throughout neurons and senses metabolic changes that occur after injury. Minimal proteomic changes are observed upon either SARM1 depletion or activation, suggesting that SARM1 does not exert broad effects on neuronal protein homeostasis. However, whether SARM1 activation occurs throughout the neuron in response to injury and cell stress remains largely unknown. Using a semiautomated imaging pipeline and a custom-built deep learning scoring algorithm, we studied degeneration in both mixed-sex mouse primary cortical neurons and male human-induced pluripotent stem cell-derived cortical neurons in response to a number of different stressors. We show that SARM1 activation is differentially restricted to specific neuronal compartments depending on the stressor. Cortical neurons undergo SARM1-dependent axon degeneration after mechanical transection, and SARM1 activation is limited to the axonal compartment distal to the injury site. However, global SARM1 activation following vacor treatment causes both cell body and axon degeneration. Context-specific stressors, such as microtubule dysfunction and mitochondrial stress, induce axonal SARM1 activation leading to SARM1-dependent axon degeneration and SARM1-independent cell body death. Our data reveal that compartment-specific SARM1-mediated death signaling is dependent on the type of injury and cellular stressor.
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Affiliation(s)
- Flora I Hinz
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | | | - Jasmine T Roberts
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Heming Yao
- Biological Research | AI Development, Genentech, Inc., South San Francisco, California 94080
| | - Shreya Gaddam
- Biological Research | AI Development, Genentech, Inc., South San Francisco, California 94080
| | - Anton Delwig
- Departments of Biochemical and Cellular Pharmacology, Genentech, Inc., South San Francisco, California 94080
| | - Samantha A Green
- Discovery Chemistry, Genentech, Inc., South San Francisco, California 94080
| | - Craig Fredrickson
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Max Adrian
- Pathology, Genentech, Inc., South San Francisco, California 94080
| | - Raymond R Asuncion
- Transgenic Technology, Genentech, Inc., South San Francisco, California 94080
| | - Tommy K Cheung
- Microchemistry, Proteomics, and Lipidomics, Genentech, Inc., South San Francisco, California 94080
| | - Margaret Hayne
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - David H Hackos
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Christopher M Rose
- Microchemistry, Proteomics, and Lipidomics, Genentech, Inc., South San Francisco, California 94080
| | - David Richmond
- Biological Research | AI Development, Genentech, Inc., South San Francisco, California 94080
| | - Casper C Hoogenraad
- Department of Neuroscience, Genentech, Inc., South San Francisco, California 94080
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10
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Schmitd LB, Hafner H, Ward A, Asghari Adib E, Biscola NP, Kohen R, Patel M, Williamson RE, Desai E, Bennett J, Saxman G, Athaiya M, Wilborn D, Shumpert J, Zhao XF, Kawaguchi R, Geschwind DH, Hoke A, Shrager P, Collins CA, Havton LA, Kalinski AL, Giger RJ. Sarm1 is not necessary for activation of neuron-intrinsic growth programs yet required for the Schwann cell repair response and peripheral nerve regeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.04.583374. [PMID: 38496662 PMCID: PMC10942360 DOI: 10.1101/2024.03.04.583374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Upon peripheral nervous system (PNS) injury, severed axons undergo rapid SARM1-dependent Wallerian degeneration (WD). In mammals, the role of SARM1 in PNS regeneration, however, is unknown. Here we demonstrate that Sarm1 is not required for axotomy induced activation of neuron-intrinsic growth programs and axonal growth into a nerve crush site. However, in the distal nerve, Sarm1 is necessary for the timely induction of the Schwann cell (SC) repair response, nerve inflammation, myelin clearance, and regeneration of sensory and motor axons. In Sarm1-/- mice, regenerated fibers exhibit reduced axon caliber, defective nerve conduction, and recovery of motor function is delayed. The growth hostile environment of Sarm1-/- distal nerve tissue was demonstrated by grafting of Sarm1-/- nerve into WT recipients. SC lineage tracing in injured WT and Sarm1-/- mice revealed morphological differences. In the Sarm1-/- distal nerve, the appearance of p75NTR+, c-Jun+ SCs is significantly delayed. Ex vivo, p75NTR and c-Jun upregulation in Sarm1-/- nerves can be rescued by pharmacological inhibition of ErbB kinase. Together, our studies show that Sarm1 is not necessary for the activation of neuron intrinsic growth programs but in the distal nerve is required for the orchestration of cellular programs that underlie rapid axon extension.
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Affiliation(s)
- Ligia B. Schmitd
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor MI, USA
| | - Hannah Hafner
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor MI, USA
| | - Ayobami Ward
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor MI, USA
- Department of Neurosurgery, University of Michigan Medical School, Ann Arbor MI, USA
| | - Elham Asghari Adib
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Natalia P. Biscola
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Rafi Kohen
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor MI, USA
| | - Manav Patel
- Department of Biology, Ball State University, Muncie IN, USA
| | | | - Emily Desai
- Department of Biology, Ball State University, Muncie IN, USA
| | | | - Grace Saxman
- Department of Biology, Ball State University, Muncie IN, USA
| | - Mitre Athaiya
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor MI, USA
| | - David Wilborn
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor MI, USA
| | - Jaisha Shumpert
- Department of Biology, Ball State University, Muncie IN, USA
| | - Xiao-Feng Zhao
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor MI, USA
| | - Riki Kawaguchi
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Daniel H. Geschwind
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
- Institute of Precision Health, University of California, Los Angeles, Los Angeles, CA, USA
| | - Ahmet Hoke
- Department of Neurology, The Johns Hopkins University, Baltimore, MD, USA
| | - Peter Shrager
- Department of Neuroscience, University of Rochester Medical Center, Rochester, NY, USA
| | - Catherine A. Collins
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, USA
| | - Leif A. Havton
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- James J Peters VA Medical Center, Bronx, NY, USA
| | - Ashley L. Kalinski
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor MI, USA
- Department of Biology, Ball State University, Muncie IN, USA
| | - Roman J. Giger
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor MI, USA
- Department of Neurology, University of Michigan Medical School, Ann Arbor MI, USA
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11
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Rahman SU, Qadeer A, Wu Z. Role and Potential Mechanisms of Nicotinamide Mononucleotide in Aging. Aging Dis 2024; 15:565-583. [PMID: 37548938 PMCID: PMC10917541 DOI: 10.14336/ad.2023.0519-1] [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: 02/17/2023] [Accepted: 05/19/2023] [Indexed: 08/08/2023] Open
Abstract
Nicotinamide adenine dinucleotide (NAD+) has recently attracted much attention due to its role in aging and lifespan extension. NAD+ directly and indirectly affects many cellular processes, including metabolic pathways, DNA repair, and immune cell activities. These mechanisms are critical for maintaining cellular homeostasis. However, the decline in NAD+ levels with aging impairs tissue function, which has been associated with several age-related diseases. In fact, the aging population has been steadily increasing worldwide, and it is important to restore NAD+ levels and reverse or delay these age-related disorders. Therefore, there is an increasing demand for healthy products that can mitigate aging, extend lifespan, and halt age-related consequences. In this case, several studies in humans and animals have targeted NAD+ metabolism with NAD+ intermediates. Among them, nicotinamide mononucleotide (NMN), a precursor in the biosynthesis of NAD+, has recently received much attention from the scientific community for its anti-aging properties. In model organisms, ingestion of NMN has been shown to improve age-related diseases and probably delay death. Here, we review aspects of NMN biosynthesis and the mechanism of its absorption, as well as potential anti-aging mechanisms of NMN, including recent preclinical and clinical tests, adverse effects, limitations, and perceived challenges.
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Affiliation(s)
- Sajid Ur Rahman
- Department of Food Science and Engineering, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Abdul Qadeer
- Institute for Infectious Diseases and Vaccine Development, Tongji University School of Medicine, Shanghai, 200072, China.
| | - Ziyun Wu
- Department of Food Science and Engineering, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
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12
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Miyamoto T, Kim C, Chow J, Dugas JC, DeGroot J, Bagdasarian AL, Thottumkara AP, Larhammar M, Calvert ME, Fox BM, Lewcock JW, Kane LA. SARM1 is responsible for calpain-dependent dendrite degeneration in mouse hippocampal neurons. J Biol Chem 2024; 300:105630. [PMID: 38199568 PMCID: PMC10862016 DOI: 10.1016/j.jbc.2024.105630] [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: 07/21/2023] [Revised: 12/10/2023] [Accepted: 12/24/2023] [Indexed: 01/12/2024] Open
Abstract
Sterile alpha and toll/interleukin receptor motif-containing 1 (SARM1) is a critical regulator of axon degeneration that acts through hydrolysis of NAD+ following injury. Recent work has defined the mechanisms underlying SARM1's catalytic activity and advanced our understanding of SARM1 function in axons, yet the role of SARM1 signaling in other compartments of neurons is still not well understood. Here, we show in cultured hippocampal neurons that endogenous SARM1 is present in axons, dendrites, and cell bodies and that direct activation of SARM1 by the neurotoxin Vacor causes not just axon degeneration, but degeneration of all neuronal compartments. In contrast to the axon degeneration pathway defined in dorsal root ganglia, SARM1-dependent hippocampal axon degeneration in vitro is not sensitive to inhibition of calpain proteases. Dendrite degeneration downstream of SARM1 in hippocampal neurons is dependent on calpain 2, a calpain protease isotype enriched in dendrites in this cell type. In summary, these data indicate SARM1 plays a critical role in neurodegeneration outside of axons and elucidates divergent pathways leading to degeneration in hippocampal axons and dendrites.
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Affiliation(s)
| | - Chaeyoung Kim
- Denali Therapeutics Inc, South San Francisco, California, USA
| | - Johann Chow
- Denali Therapeutics Inc, South San Francisco, California, USA
| | - Jason C Dugas
- Denali Therapeutics Inc, South San Francisco, California, USA
| | - Jack DeGroot
- Denali Therapeutics Inc, South San Francisco, California, USA
| | | | | | | | | | - Brian M Fox
- Denali Therapeutics Inc, South San Francisco, California, USA
| | | | - Lesley A Kane
- Denali Therapeutics Inc, South San Francisco, California, USA.
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13
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Li F, Wu C, Wang G. Targeting NAD Metabolism for the Therapy of Age-Related Neurodegenerative Diseases. Neurosci Bull 2024; 40:218-240. [PMID: 37253984 PMCID: PMC10838897 DOI: 10.1007/s12264-023-01072-3] [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: 01/25/2023] [Accepted: 04/10/2023] [Indexed: 06/01/2023] Open
Abstract
As the aging population continues to grow rapidly, age-related diseases are becoming an increasing burden on the healthcare system and a major concern for the well-being of elderly individuals. While aging is an inevitable process for all humans, it can be slowed down and age-related diseases can be treated or alleviated. Nicotinamide adenine dinucleotide (NAD) is a critical coenzyme or cofactor that plays a central role in metabolism and is involved in various cellular processes including the maintenance of metabolic homeostasis, post-translational protein modifications, DNA repair, and immune responses. As individuals age, their NAD levels decline, and this decrease has been suggested to be a contributing factor to the development of numerous age-related diseases, such as cancer, diabetes, cardiovascular diseases, and neurodegenerative diseases. In pursuit of healthy aging, researchers have investigated approaches to boost or maintain NAD levels. Here, we provide an overview of NAD metabolism and the role of NAD in age-related diseases and summarize recent progress in the development of strategies that target NAD metabolism for the treatment of age-related diseases, particularly neurodegenerative diseases.
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Affiliation(s)
- Feifei Li
- School of Pharmaceutical Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tsinghua University, Beijing, 100084, China
| | - Chou Wu
- School of Pharmaceutical Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Gelin Wang
- School of Pharmaceutical Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Tsinghua University, Beijing, 100084, China.
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14
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Yang S, Niou ZX, Enriquez A, LaMar J, Huang JY, Ling K, Jafar-Nejad P, Gilley J, Coleman MP, Tennessen JM, Rangaraju V, Lu HC. NMNAT2 supports vesicular glycolysis via NAD homeostasis to fuel fast axonal transport. Mol Neurodegener 2024; 19:13. [PMID: 38282024 PMCID: PMC10823734 DOI: 10.1186/s13024-023-00690-9] [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: 05/09/2023] [Accepted: 11/28/2023] [Indexed: 01/30/2024] Open
Abstract
BACKGROUND Bioenergetic maladaptations and axonopathy are often found in the early stages of neurodegeneration. Nicotinamide adenine dinucleotide (NAD), an essential cofactor for energy metabolism, is mainly synthesized by Nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2) in CNS neurons. NMNAT2 mRNA levels are reduced in the brains of Alzheimer's, Parkinson's, and Huntington's disease. Here we addressed whether NMNAT2 is required for axonal health of cortical glutamatergic neurons, whose long-projecting axons are often vulnerable in neurodegenerative conditions. We also tested if NMNAT2 maintains axonal health by ensuring axonal ATP levels for axonal transport, critical for axonal function. METHODS We generated mouse and cultured neuron models to determine the impact of NMNAT2 loss from cortical glutamatergic neurons on axonal transport, energetic metabolism, and morphological integrity. In addition, we determined if exogenous NAD supplementation or inhibiting a NAD hydrolase, sterile alpha and TIR motif-containing protein 1 (SARM1), prevented axonal deficits caused by NMNAT2 loss. This study used a combination of techniques, including genetics, molecular biology, immunohistochemistry, biochemistry, fluorescent time-lapse imaging, live imaging with optical sensors, and anti-sense oligos. RESULTS We provide in vivo evidence that NMNAT2 in glutamatergic neurons is required for axonal survival. Using in vivo and in vitro studies, we demonstrate that NMNAT2 maintains the NAD-redox potential to provide "on-board" ATP via glycolysis to vesicular cargos in distal axons. Exogenous NAD+ supplementation to NMNAT2 KO neurons restores glycolysis and resumes fast axonal transport. Finally, we demonstrate both in vitro and in vivo that reducing the activity of SARM1, an NAD degradation enzyme, can reduce axonal transport deficits and suppress axon degeneration in NMNAT2 KO neurons. CONCLUSION NMNAT2 ensures axonal health by maintaining NAD redox potential in distal axons to ensure efficient vesicular glycolysis required for fast axonal transport.
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Affiliation(s)
- Sen Yang
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
| | - Zhen-Xian Niou
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA
| | - Andrea Enriquez
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA
| | - Jacob LaMar
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
- Present address: Department of Biomedical Science, Florida Atlantic University, Jupiter, FL, 33458, USA
| | - Jui-Yen Huang
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
| | - Karen Ling
- Neuroscience Drug Discovery, Ionis Pharmaceuticals, Inc., 2855, Gazelle Court, Carlsbad, CA, 92010, USA
| | - Paymaan Jafar-Nejad
- Neuroscience Drug Discovery, Ionis Pharmaceuticals, Inc., 2855, Gazelle Court, Carlsbad, CA, 92010, USA
| | - Jonathan Gilley
- Department of Clinical Neuroscience, Cambridge University, Cambridge, UK
| | - Michael P Coleman
- Department of Clinical Neuroscience, Cambridge University, Cambridge, UK
| | - Jason M Tennessen
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA
| | - Vidhya Rangaraju
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
| | - Hui-Chen Lu
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA.
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA.
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA.
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15
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Tarasiuk O, Molteni L, Malacrida A, Nicolini G. The Role of NMNAT2/SARM1 in Neuropathy Development. BIOLOGY 2024; 13:61. [PMID: 38275737 PMCID: PMC10813049 DOI: 10.3390/biology13010061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 01/15/2024] [Accepted: 01/19/2024] [Indexed: 01/27/2024]
Abstract
Chemotherapy-induced peripheral neuropathy (CIPN) commonly arises as a side effect of diverse cancer chemotherapy treatments. This condition presents symptoms such as numbness, tingling, and altered sensation in patients, often accompanied by neuropathic pain. Pathologically, CIPN is characterized by an intensive "dying-back" axonopathy, starting at the intra-epidermal sensory innervations and advancing retrogradely. The lack of comprehensive understanding regarding its underlying mechanisms explains the absence of effective treatments for CIPN. Recent investigations into axon degeneration mechanisms have pinpointed nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2) and sterile alpha and TIR motif-containing 1 protein (SARM1) as pivotal mediators of injury-induced axonal degeneration. In this review, we aim to explore various studies shedding light on the interplay between NMNAT2 and SARM1 proteins and their roles in the progression of CIPN.
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Affiliation(s)
- Olga Tarasiuk
- Experimental Neurology Unit, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy; (L.M.); (A.M.); (G.N.)
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16
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Fernández-Lázaro D, Sanz B, Seco-Calvo J. The Mechanisms of Regulated Cell Death: Structural and Functional Proteomic Pathways Induced or Inhibited by a Specific Protein-A Narrative Review. Proteomes 2024; 12:3. [PMID: 38250814 PMCID: PMC10801515 DOI: 10.3390/proteomes12010003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 12/30/2023] [Accepted: 01/03/2024] [Indexed: 01/23/2024] Open
Abstract
Billions of cells die in us every hour, and our tissues do not shrink because there is a natural regulation where Cell Death (CD) is balanced with cell division. The process in which cells eliminate themselves in a controlled manner is called Programmed Cell Death (PCD). The PCD plays an important role during embryonic development, in maintaining homeostasis of the body's tissues, and in the elimination of damaged cells, under a wide range of physiological and developmental stimuli. A multitude of protein mediators of PCD have been identified and signals have been found to utilize common pathways elucidating the proteins involved. This narrative review focuses on caspase-dependent and caspase-independent PCD pathways. Included are studies of caspase-dependent PCD such as Anoikis, Catastrophe Mitotic, Pyroptosis, Emperitosis, Parthanatos and Cornification, and Caspase-Independent PCD as Wallerian Degeneration, Ferroptosis, Paraptosis, Entosis, Methuosis, and Extracellular Trap Abnormal Condition (ETosis), as well as neutrophil extracellular trap abnormal condition (NETosis) and Eosinophil Extracellular Trap Abnormal Condition (EETosis). Understanding PCD from those reported in this review could shed substantial light on the processes of biological homeostasis. In addition, identifying specific proteins involved in these processes is mandatory to identify molecular biomarkers, as well as therapeutic targets. This knowledge could provide the ability to modulate the PCD response and could lead to new therapeutic interventions in a wide range of diseases.
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Affiliation(s)
- Diego Fernández-Lázaro
- Department of Cellular Biology, Genetics, Histology and Pharmacology, Faculty of Health Sciences, University of Valladolid, Campus of Soria, 42004 Soria, Spain
- Neurobiology Research Group, Faculty of Medicine, University of Valladolid, 47005 Valladolid, Spain
- SARCELLOMICS® Research Group, 27071 León, Spain
| | - Begoña Sanz
- SARCELLOMICS® Research Group, 27071 León, Spain
- Department of Physiology, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain
- Biocruces Bizkaia Health Research Institute, 48903 Barakaldo, Spain
| | - Jesús Seco-Calvo
- SARCELLOMICS® Research Group, 27071 León, Spain
- Department of Physiology, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain
- Institute of Biomedicine (IBIOMED), Universidad de León, 27071 León, Spain
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17
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Lautrup S, Hou Y, Fang EF, Bohr VA. Roles of NAD + in Health and Aging. Cold Spring Harb Perspect Med 2024; 14:a041193. [PMID: 37848251 PMCID: PMC10759992 DOI: 10.1101/cshperspect.a041193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2023]
Abstract
NAD+, the essential metabolite involved in multiple reactions such as the regulation of cellular metabolism, energy production, DNA repair, mitophagy and autophagy, inflammation, and neuronal function, has been the subject of intense research in the field of aging and disease over the last decade. NAD+ levels decline with aging and in some age-related diseases, and reduction in NAD+ affects all the hallmarks of aging. Here, we present an overview of the discovery of NAD+, the cellular pathways of producing and consuming NAD+, and discuss how imbalances in the production rate and cellular request of NAD+ likely contribute to aging and age-related diseases including neurodegeneration. Preclinical studies have revealed great potential for NAD+ precursors in promotion of healthy aging and improvement of neurodegeneration. This has led to the initiation of several clinical trials with NAD+ precursors to treat accelerated aging, age-associated dysfunctions, and diseases including Alzheimer's and Parkinson's. NAD supplementation has great future potential clinically, and these studies will also provide insight into the mechanisms of aging.
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Affiliation(s)
- Sofie Lautrup
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway
| | - Yujun Hou
- Institute for Regenerative Medicine, Shanghai East Hospital, Frontier Science Center for Stem Cell Research, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Evandro F Fang
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway
- The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway
| | - Vilhelm A Bohr
- DNA Repair Section, National Institute on Aging, National Institutes of Health, Baltimore, Maryland 21224, USA
- Danish Center for Healthy Aging, University of Copenhagen, 2200 Copenhagen, Denmark
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18
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Funakoshi M, Araki T. Mechanism of initiation and regulation of axonal degeneration with special reference to NMNATs and Sarm1. Neurosci Res 2023; 197:3-8. [PMID: 34767875 DOI: 10.1016/j.neures.2021.11.002] [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: 11/01/2021] [Accepted: 11/01/2021] [Indexed: 10/19/2022]
Abstract
Axonal degeneration is observed in a variety of contexts in both the central and peripheral nervous systems. Pathological signaling to regulate the progression of axonal degeneration has long been studied using Wallerian degeneration, the prototypical axonal degradation observed after injury, as a representative model. Understanding metabolism of nicotinamide adenine dinucleotide (NAD+) and the functional regulation of Sarm1 has generated great progress in this field, but there are a number of remaining questions. Here, in this short review, we describe our current understanding of the axonal degeneration mechanism, with special reference to the biology related to wlds mice and Sarm1. Furthermore, variations of axonal degeneration initiation are discussed in order to address the remaining questions needed for mechanistic clarification.
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Affiliation(s)
- Masabumi Funakoshi
- Department of Peripheral Nervous System Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo, 187-8502, Japan
| | - Toshiyuki Araki
- Department of Peripheral Nervous System Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo, 187-8502, Japan.
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19
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Kitaoka Y, Sase K. Molecular aspects of optic nerve autophagy in glaucoma. Mol Aspects Med 2023; 94:101217. [PMID: 37839231 DOI: 10.1016/j.mam.2023.101217] [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: 06/30/2023] [Revised: 09/24/2023] [Accepted: 10/08/2023] [Indexed: 10/17/2023]
Abstract
The optic nerve consists of the glia, vessels, and axons including myelin and axoplasm. Since axonal degeneration precedes retinal ganglion cell death in glaucoma, the preceding axonal degeneration model may be helpful for understanding the molecular mechanisms of optic nerve degeneration. Optic nerve samples from these models can provide information on several aspects of autophagy. Autophagosomes, the most typical organelles expressing autophagy, are found much more frequently inside axons than around the glia. Thus, immunoblot findings from the optic nerve can reflect the autophagy state in axons. Autophagic flux impairment may occur in degenerating optic nerve axons, as in other central nervous system neurodegenerative diseases. Several molecular candidates are involved in autophagy enhancement, leading to axonal protection. This concept is an attractive approach to the prevention of further retinal ganglion cell death. In this review, we describe the factors affecting autophagy, including nicotinamide riboside, p38, ULK, AMPK, ROCK, and SIRT1, in the optic nerve and propose potential methods of axonal protection via enhancement of autophagy.
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Affiliation(s)
- Yasushi Kitaoka
- Department of Ophthalmology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa, 216-8511, Japan; Department of Molecular Neuroscience, St. Marianna University Graduate School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa, 216-8511, Japan.
| | - Kana Sase
- Department of Ophthalmology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa, 216-8511, Japan
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20
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Loreto A, Antoniou C, Merlini E, Gilley J, Coleman MP. NMN: The NAD precursor at the intersection between axon degeneration and anti-ageing therapies. Neurosci Res 2023; 197:18-24. [PMID: 36657725 DOI: 10.1016/j.neures.2023.01.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 01/18/2023]
Abstract
The past 20 years of research on axon degeneration has revealed fine details on how NAD biology controls axonal survival. Extensive data demonstrate that the NAD precursor NMN binds to and activates the pro-degenerative enzyme SARM1, so a failure to convert sufficient NMN into NAD leads to toxic NMN accumulation and axon degeneration. This involvement of NMN brings the axon degeneration field to an unexpected overlap with research into ageing and extending healthy lifespan. A decline in NAD levels throughout life, at least in some tissues, is believed to contribute to age-related functional decay and boosting NAD production with supplementation of NMN or other NAD precursors has gained attention as a potential anti-ageing therapy. Recent years have witnessed an influx of NMN-based products and related molecules on the market, sold as food supplements, with many people taking these supplements daily. While several clinical trials are ongoing to check the safety profiles and efficacy of NAD precursors, sufficient data to back their therapeutic use are still lacking. Here, we discuss NMN supplementation, SARM1 and anti-ageing strategies, with an important question in mind: considering that NMN accumulation can lead to axon degeneration, how is this compatible with its beneficial effect in ageing and are there circumstances in which NMN supplementation could become harmful?
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Affiliation(s)
- Andrea Loreto
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, CB2 0PY Cambridge, UK.
| | - Christina Antoniou
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, CB2 0PY Cambridge, UK
| | - Elisa Merlini
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, CB2 0PY Cambridge, UK
| | - Jonathan Gilley
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, CB2 0PY Cambridge, UK
| | - Michael P Coleman
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Forvie Site, Robinson Way, CB2 0PY Cambridge, UK.
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21
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Alexandris AS, Koliatsos VE. NAD +, Axonal Maintenance, and Neurological Disease. Antioxid Redox Signal 2023; 39:1167-1184. [PMID: 37503611 PMCID: PMC10715442 DOI: 10.1089/ars.2023.0350] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 05/28/2023] [Indexed: 07/29/2023]
Abstract
Significance: The remarkable geometry of the axon exposes it to unique challenges for survival and maintenance. Axonal degeneration is a feature of peripheral neuropathies, glaucoma, and traumatic brain injury, and an early event in neurodegenerative diseases. Since the discovery of Wallerian degeneration (WD), a molecular program that hijacks nicotinamide adenine dinucleotide (NAD+) metabolism for axonal self-destruction, the complex roles of NAD+ in axonal viability and disease have become research priority. Recent Advances: The discoveries of the protective Wallerian degeneration slow (WldS) and of sterile alpha and TIR motif containing 1 (SARM1) activation as the main instructive signal for WD have shed new light on the regulatory role of NAD+ in axonal degeneration in a growing number of neurological diseases. SARM1 has been characterized as a NAD+ hydrolase and sensor of NAD+ metabolism. The discovery of regulators of nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2) proteostasis in axons, the allosteric regulation of SARM1 by NAD+ and NMN, and the existence of clinically relevant windows of action of these signals has opened new opportunities for therapeutic interventions, including SARM1 inhibitors and modulators of NAD+ metabolism. Critical Issues: Events upstream and downstream of SARM1 remain unclear. Furthermore, manipulating NAD+ metabolism, an overdetermined process crucial in cell survival, for preventing the degeneration of the injured axon may be difficult and potentially toxic. Future Directions: There is a need for clarification of the distinct roles of NAD+ metabolism in axonal maintenance as contrasted to WD. There is also a need to better understand the role of NAD+ metabolism in axonal endangerment in neuropathies, diseases of the white matter, and the early stages of neurodegenerative diseases of the central nervous system. Antioxid. Redox Signal. 39, 1167-1184.
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Affiliation(s)
| | - Vassilis E. Koliatsos
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Neurology, and Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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22
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Waller TJ, Collins CA. Opposing roles of Fos, Raw, and SARM1 in the regulation of axonal degeneration and synaptic structure. Front Cell Neurosci 2023; 17:1283995. [PMID: 38099151 PMCID: PMC10719852 DOI: 10.3389/fncel.2023.1283995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Accepted: 10/30/2023] [Indexed: 12/17/2023] Open
Abstract
Introduction The degeneration of injured axons is driven by conserved molecules, including the sterile armadillo TIR domain-containing protein SARM1, the cJun N-terminal kinase JNK, and regulators of these proteins. These molecules are also implicated in the regulation of synapse development though the mechanistic relationship of their functions in degeneration vs. development is poorly understood. Results and discussion Here, we uncover disparate functional relationships between SARM1 and the transmembrane protein Raw in the regulation of Wallerian degeneration and synaptic growth in motoneurons of Drosophila melanogaster. Our genetic data suggest that Raw antagonizes the downstream output MAP kinase signaling mediated by Drosophila SARM1 (dSarm). This relationship is revealed by dramatic synaptic overgrowth phenotypes at the larval neuromuscular junction when motoneurons are depleted for Raw or overexpress dSarm. While Raw antagonizes the downstream output of dSarm to regulate synaptic growth, it shows an opposite functional relationship with dSarm for axonal degeneration. Loss of Raw leads to decreased levels of dSarm in axons and delayed axonal degeneration that is rescued by overexpression of dSarm, supporting a model that Raw promotes the activation of dSarm in axons. However, inhibiting Fos also decreases dSarm levels in axons but has the opposite outcome of enabling Wallerian degeneration. The combined genetic data suggest that Raw, dSarm, and Fos influence each other's functions through multiple points of regulation to control the structure of synaptic terminals and the resilience of axons to degeneration.
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Affiliation(s)
- Thomas J. Waller
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | - Catherine A. Collins
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
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23
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Zuo Z, Zhang Z, Zhang S, Fan B, Li G. The Molecular Mechanisms Involved in Axonal Degeneration and Retrograde Retinal Ganglion Cell Death. DNA Cell Biol 2023; 42:653-667. [PMID: 37819746 DOI: 10.1089/dna.2023.0180] [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] [Indexed: 10/13/2023] Open
Abstract
Axonal degeneration is a pathologic change common to multiple retinopathies and optic neuropathies. Various pathologic factors, such as mechanical injury, inflammation, and ischemia, can damage retinal ganglion cell (RGC) somas and axons, eventually triggering axonal degeneration and RGC death. The molecular mechanisms of somal and axonal degeneration are distinct but also overlap, and axonal degeneration can result in retrograde somal degeneration. While the mitogen-activated protein kinase pathway acts as a central node in RGC axon degeneration, several newly discovered molecules, such as sterile alpha and Toll/interleukin-1 receptor motif-containing protein 1 and nicotinamide mononucleotide adenylyltransferase 2, also play a critical role in this pathological process following different types of injury. Therefore, we summarize the types of injury that cause RGC axon degeneration and retrograde RGC death and important underlying molecular mechanisms, providing a reference for the identification of targets for protecting axons and RGCs.
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Affiliation(s)
- Zhaoyang Zuo
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, China
| | - Ziyuan Zhang
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, China
| | - Siming Zhang
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, China
| | - Bin Fan
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, China
| | - Guangyu Li
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, China
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Icso JD, Thompson PR. A phase transition reduces the threshold for nicotinamide mononucleotide-based activation of SARM1, an NAD(P) hydrolase, to physiologically relevant levels. J Biol Chem 2023; 299:105284. [PMID: 37742918 PMCID: PMC10624580 DOI: 10.1016/j.jbc.2023.105284] [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: 07/07/2023] [Revised: 09/04/2023] [Accepted: 09/19/2023] [Indexed: 09/26/2023] Open
Abstract
Axonal degeneration is a hallmark feature of neurodegenerative diseases. Activation of the NAD(P)ase sterile alpha and toll-interleukin receptor motif containing protein 1 (SARM1) is critical for this process. In resting neurons, SARM1 activity is inhibited, but upon damage, SARM1 is activated and catalyzes one of three NAD(P)+ dependent reactions: (1) NAD(P)+ hydrolysis to form ADP-ribose (ADPR[P]) and nicotinamide; (2) the formation of cyclic-ADPR (cADPR[P]); or (3) a base exchange reaction with nicotinic acid (NA) and NADP+ to form NA adenine dinucleotide phosphate. Production of these metabolites triggers axonal death. Two activation mechanisms have been proposed: (1) an increase in the nicotinamide mononucleotide (NMN) concentration, which leads to the allosteric activation of SARM1, and (2) a phase transition, which stabilizes the active conformation of the enzyme. However, neither of these mechanisms have been shown to occur at the same time. Using in vitro assay systems, we show that the liquid-to-solid phase transition lowers the NMN concentration required to activate the catalytic activity of SARM1 by up to 140-fold. These results unify the proposed activation mechanisms and show for the first time that a phase transition reduces the threshold for NMN-based SARM1 activation to physiologically relevant levels. These results further our understanding of SARM1 activation and will be important for the future development of therapeutics targeting SARM1.
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Affiliation(s)
- Janneke Doedée Icso
- Program in Chemical Biology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA; Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medial School, Worcester, Massachusetts, USA
| | - Paul Ryan Thompson
- Program in Chemical Biology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA; Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medial School, Worcester, Massachusetts, USA.
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25
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Park SB, Cetinkaya-Fisgin A, Argyriou AA, Höke A, Cavaletti G, Alberti P. Axonal degeneration in chemotherapy-induced peripheral neurotoxicity: clinical and experimental evidence. J Neurol Neurosurg Psychiatry 2023; 94:962-972. [PMID: 37015772 PMCID: PMC10579520 DOI: 10.1136/jnnp-2021-328323] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 02/15/2023] [Indexed: 04/06/2023]
Abstract
Multiple pathological mechanisms are involved in the development of chemotherapy-induced peripheral neurotoxicity (CIPN). Recent work has provided insights into the molecular mechanisms underlying chemotherapy-induced axonal degeneration. This review integrates evidence from preclinical and clinical work on the onset, progression and outcome of axonal degeneration in CIPN. We review likely triggers of axonal degeneration in CIPN and highlight evidence of molecular pathways involved in axonal degeneration and their relevance to CIPN, including SARM1-mediated axon degeneration pathway. We identify potential clinical markers of axonal dysfunction to provide early identification of toxicity as well as present potential treatment strategies to intervene in axonal degeneration pathways. A greater understanding of axonal degeneration processes in CIPN will provide important information regarding the development and progression of axonal dysfunction more broadly and will hopefully assist in the development of successful interventions for CIPN and other neurodegenerative disorders.
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Affiliation(s)
- Susanna B Park
- Brain and Mind Centre, Faculty of Medicine and Health, School of Medical Sciences, University of Sydney, Camperdown, New South Wales, Australia
| | - Aysel Cetinkaya-Fisgin
- Department of Neurology, Neuromuscular Division, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Andreas A Argyriou
- Department of Neurology, "Agios Andreas" State General Hospital of Patras, Patras, Greece
| | - Ahmet Höke
- Department of Neurology, Neuromuscular Division, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Guido Cavaletti
- Experimental Neurology Unit and Milan Center for Neuroscience, University of Milano-Bicocca, Monza, Italy
| | - Paola Alberti
- Experimental Neurology Unit and Milan Center for Neuroscience, University of Milano-Bicocca, Monza, Italy
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Metcalfe M, David BT, Langley BC, Hill CE. Elevation of NAD + by nicotinamide riboside spares spinal cord tissue from injury and promotes locomotor recovery. Exp Neurol 2023; 368:114479. [PMID: 37454712 DOI: 10.1016/j.expneurol.2023.114479] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 06/28/2023] [Accepted: 07/12/2023] [Indexed: 07/18/2023]
Abstract
Spinal cord injury (SCI)-induced tissue damage spreads to neighboring spared cells in the hours, days, and weeks following injury, leading to exacerbation of tissue damage and functional deficits. Among the biochemical changes is the rapid reduction of cellular nicotinamide adenine dinucleotide (NAD+), an essential coenzyme for energy metabolism and an essential cofactor for non-redox NAD+-dependent enzymes with critical functions in sensing and repairing damaged tissue. NAD+ depletion propagates tissue damage. Augmenting NAD+ by exogenous application of NAD+, its synthesizing enzymes, or its cellular precursors mitigates tissue damage. Nicotinamide riboside (NR) is considered to be one of the most promising NAD+ precursors for clinical application due to its ability to safely and effectively boost cellular NAD+ synthesis in rats and humans. Moreover, various preclinical studies have demonstrated that NR can provide tissue protection. Despite these promising findings, little is known about the potential benefits of NR in the context of SCI. In the current study, we tested whether NR administration could effectively increase NAD+ levels in the injured spinal cord and whether this augmentation of NAD+ would promote spinal cord tissue protection and ultimately lead to improvements in locomotor function. Our findings indicate that administering NR (500 mg/kg) intraperitoneally from four days before to two weeks after a mid-thoracic contusion-SCI injury, effectively doubles NAD+ levels in the spinal cord of Long-Evans rats. Moreover, NR administration plays a protective role in preserving spinal cord tissue post-injury, particularly in neurons and axons, as evident from the observed gray and white matter sparing. Additionally, it enhances motor function, as evaluated through the BBB subscore and missteps on the horizontal ladderwalk. Collectively, these findings demonstrate that administering NR, a precursor of NAD+, increases NAD+ within the injured spinal cord and effectively mitigates the tissue damage and functional decline that occurs following SCI.
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Affiliation(s)
- Mariajose Metcalfe
- Burke Neurological Institute, White Plains, NY, United States; Weill Cornell Medicine, Feil Family Brain and Mind Research Institute, New York, NY, United States.
| | - Brian T David
- Burke Neurological Institute, White Plains, NY, United States; Weill Cornell Medicine, Feil Family Brain and Mind Research Institute, New York, NY, United States.
| | - Brett C Langley
- Burke Neurological Institute, White Plains, NY, United States; Weill Cornell Medicine, Feil Family Brain and Mind Research Institute, New York, NY, United States.
| | - Caitlin E Hill
- Burke Neurological Institute, White Plains, NY, United States; Weill Cornell Medicine, Feil Family Brain and Mind Research Institute, New York, NY, United States.
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Khazma T, Grossman A, Guez-Haddad J, Feng C, Dabas H, Sain R, Weitman M, Zalk R, Isupov MN, Hammarlund M, Hons M, Opatowsky Y. Structure-function analysis of ceTIR-1/hSARM1 explains the lack of Wallerian axonal degeneration in C. elegans. Cell Rep 2023; 42:113026. [PMID: 37635352 PMCID: PMC10675840 DOI: 10.1016/j.celrep.2023.113026] [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: 01/07/2023] [Revised: 06/05/2023] [Accepted: 08/09/2023] [Indexed: 08/29/2023] Open
Abstract
Wallerian axonal degeneration (WD) does not occur in the nematode C. elegans, in contrast to other model animals. However, WD depends on the NADase activity of SARM1, a protein that is also expressed in C. elegans (ceSARM/ceTIR-1). We hypothesized that differences in SARM between species might exist and account for the divergence in WD. We first show that expression of the human (h)SARM1, but not ceTIR-1, in C. elegans neurons is sufficient to confer axon degeneration after nerve injury. Next, we determined the cryoelectron microscopy structure of ceTIR-1 and found that, unlike hSARM1, which exists as an auto-inhibited ring octamer, ceTIR-1 forms a readily active 9-mer. Enzymatically, the NADase activity of ceTIR-1 is substantially weaker (10-fold higher Km) than that of hSARM1, and even when fully active, it falls short of consuming all cellular NAD+. Our experiments provide insight into the molecular mechanisms and evolution of SARM orthologs and WD across species.
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Affiliation(s)
- Tami Khazma
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Atira Grossman
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Julia Guez-Haddad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Chengye Feng
- Departments of Neuroscience and Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Hadas Dabas
- Departments of Neuroscience and Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Radhika Sain
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Michal Weitman
- Department of Chemistry, Bar-Ilan University, Ramat Gan, Israel
| | - Ran Zalk
- Ilse Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Michail N Isupov
- Henry Wellcome Building for Biocatalysis, Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
| | - Marc Hammarlund
- Departments of Neuroscience and Genetics, Yale School of Medicine, New Haven, CT, USA.
| | - Michael Hons
- European Molecular Biology Laboratory, Grenoble, France.
| | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
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28
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Bhattacharya MRC. A nerve-wracking buzz: lessons from Drosophila models of peripheral neuropathy and axon degeneration. Front Aging Neurosci 2023; 15:1166146. [PMID: 37614471 PMCID: PMC10442544 DOI: 10.3389/fnagi.2023.1166146] [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: 02/14/2023] [Accepted: 07/24/2023] [Indexed: 08/25/2023] Open
Abstract
The degeneration of axons and their terminals occurs following traumatic, toxic, or genetically-induced insults. Common molecular mechanisms unite these disparate triggers to execute a conserved nerve degeneration cascade. In this review, we will discuss how models of peripheral nerve injury and neuropathy in Drosophila have led the way in advancing molecular understanding of axon degeneration and nerve injury pathways. Both neuron-intrinsic as well as glial responses to injury will be highlighted. Finally, we will offer perspective on what additional questions should be answered to advance these discoveries toward clinical interventions for patients with neuropathy.
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29
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Minckley TF, Salvagio LA, Fudge DH, Verhey K, Markus SM, Qin Y. Zn2+ decoration of microtubules arrests axonal transport and displaces tau, doublecortin, and MAP2C. J Cell Biol 2023; 222:e202208121. [PMID: 37326602 PMCID: PMC10276529 DOI: 10.1083/jcb.202208121] [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: 08/22/2022] [Revised: 03/31/2023] [Accepted: 05/11/2023] [Indexed: 06/17/2023] Open
Abstract
Intracellular Zn2+ concentrations increase via depolarization-mediated influx or intracellular release, but the immediate effects of Zn2+ signals on neuron function are not fully understood. By simultaneous recording of cytosolic Zn2+ and organelle motility, we find that elevated Zn2+ (IC50 ≈ 5-10 nM) reduces both lysosomal and mitochondrial motility in primary rat hippocampal neurons and HeLa cells. Using live-cell confocal microscopy and in vitro single-molecule TIRF imaging, we reveal that Zn2+ inhibits activity of motor proteins (kinesin and dynein) without disrupting their microtubule binding. Instead, Zn2+ directly binds to microtubules and selectively promotes detachment of tau, DCX, and MAP2C, but not MAP1B, MAP4, MAP7, MAP9, or p150glued. Bioinformatic predictions and structural modeling show that the Zn2+ binding sites on microtubules partially overlap with the microtubule binding sites of tau, DCX, dynein, and kinesin. Our results reveal that intraneuronal Zn2+ regulates axonal transport and microtubule-based processes by interacting with microtubules.
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Affiliation(s)
- Taylor F. Minckley
- Department of Biological Sciences, University of Denver, Denver, CO, USA
| | | | - Dylan H. Fudge
- Department of Biological Sciences, University of Denver, Denver, CO, USA
| | - Kristen Verhey
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Steven M. Markus
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Yan Qin
- Department of Biological Sciences, University of Denver, Denver, CO, USA
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30
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Tribble JR, Hui F, Quintero H, El Hajji S, Bell K, Di Polo A, Williams PA. Neuroprotection in glaucoma: Mechanisms beyond intraocular pressure lowering. Mol Aspects Med 2023; 92:101193. [PMID: 37331129 DOI: 10.1016/j.mam.2023.101193] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/25/2023] [Accepted: 06/04/2023] [Indexed: 06/20/2023]
Abstract
Glaucoma is a common, complex, multifactorial neurodegenerative disease characterized by progressive dysfunction and then loss of retinal ganglion cells, the output neurons of the retina. Glaucoma is the most common cause of irreversible blindness and affects ∼80 million people worldwide with many more undiagnosed. The major risk factors for glaucoma are genetics, age, and elevated intraocular pressure. Current strategies only target intraocular pressure management and do not directly target the neurodegenerative processes occurring at the level of the retinal ganglion cell. Despite strategies to manage intraocular pressure, as many as 40% of glaucoma patients progress to blindness in at least one eye during their lifetime. As such, neuroprotective strategies that target the retinal ganglion cell and these neurodegenerative processes directly are of great therapeutic need. This review will cover the recent advances from basic biology to on-going clinical trials for neuroprotection in glaucoma covering degenerative mechanisms, metabolism, insulin signaling, mTOR, axon transport, apoptosis, autophagy, and neuroinflammation. With an increased understanding of both the basic and clinical mechanisms of the disease, we are closer than ever to a neuroprotective strategy for glaucoma.
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Affiliation(s)
- James R Tribble
- Department of Clinical Neuroscience, Division of Eye and Vision, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Flora Hui
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia; Department of Optometry & Vision Sciences, The University of Melbourne, Melbourne, Australia
| | - Heberto Quintero
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Sana El Hajji
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Katharina Bell
- NHMRC Clinical Trials Centre, University of Sydney, Australia; Eye ACP Duke-NUS, Singapore
| | - Adriana Di Polo
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Pete A Williams
- Department of Clinical Neuroscience, Division of Eye and Vision, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden.
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Yang S, Park JH, Lu HC. Axonal energy metabolism, and the effects in aging and neurodegenerative diseases. Mol Neurodegener 2023; 18:49. [PMID: 37475056 PMCID: PMC10357692 DOI: 10.1186/s13024-023-00634-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 06/08/2023] [Indexed: 07/22/2023] Open
Abstract
Human studies consistently identify bioenergetic maladaptations in brains upon aging and neurodegenerative disorders of aging (NDAs), such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and Amyotrophic lateral sclerosis. Glucose is the major brain fuel and glucose hypometabolism has been observed in brain regions vulnerable to aging and NDAs. Many neurodegenerative susceptible regions are in the topological central hub of the brain connectome, linked by densely interconnected long-range axons. Axons, key components of the connectome, have high metabolic needs to support neurotransmission and other essential activities. Long-range axons are particularly vulnerable to injury, neurotoxin exposure, protein stress, lysosomal dysfunction, etc. Axonopathy is often an early sign of neurodegeneration. Recent studies ascribe axonal maintenance failures to local bioenergetic dysregulation. With this review, we aim to stimulate research in exploring metabolically oriented neuroprotection strategies to enhance or normalize bioenergetics in NDA models. Here we start by summarizing evidence from human patients and animal models to reveal the correlation between glucose hypometabolism and connectomic disintegration upon aging/NDAs. To encourage mechanistic investigations on how axonal bioenergetic dysregulation occurs during aging/NDAs, we first review the current literature on axonal bioenergetics in distinct axonal subdomains: axon initial segments, myelinated axonal segments, and axonal arbors harboring pre-synaptic boutons. In each subdomain, we focus on the organization, activity-dependent regulation of the bioenergetic system, and external glial support. Second, we review the mechanisms regulating axonal nicotinamide adenine dinucleotide (NAD+) homeostasis, an essential molecule for energy metabolism processes, including NAD+ biosynthetic, recycling, and consuming pathways. Third, we highlight the innate metabolic vulnerability of the brain connectome and discuss its perturbation during aging and NDAs. As axonal bioenergetic deficits are developing into NDAs, especially in asymptomatic phase, they are likely exaggerated further by impaired NAD+ homeostasis, the high energetic cost of neural network hyperactivity, and glial pathology. Future research in interrogating the causal relationship between metabolic vulnerability, axonopathy, amyloid/tau pathology, and cognitive decline will provide fundamental knowledge for developing therapeutic interventions.
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Affiliation(s)
- Sen Yang
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA
| | - Jung Hyun Park
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA
| | - Hui-Chen Lu
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA.
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA.
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA.
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Thornburg-Suresh EJC, Richardson JE, Summers DW. The Stathmin-2 membrane-targeting domain is required for axon protection and regulated degradation by DLK signaling. J Biol Chem 2023; 299:104861. [PMID: 37236359 PMCID: PMC10404615 DOI: 10.1016/j.jbc.2023.104861] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 05/16/2023] [Accepted: 05/19/2023] [Indexed: 05/28/2023] Open
Abstract
Axon integrity is essential for functional connectivity in the nervous system. The degeneration of stressed or damaged axons is a common and sometimes initiating event in neurodegenerative disorders. Stathmin-2 (Stmn2) is an axon maintenance factor that is depleted in amyotrophic lateral sclerosis, and replenishment of Stmn2 can restore neurite outgrowth in diseased neurons. However, mechanisms responsible for Stmn2-mediated axon maintenance in injured neurons are not known. We used primary sensory neurons to interrogate the role of Stmn2 in the degeneration of severed axons. We discover that membrane association of Stmn2 is critical for its axon-protective activity. Structure-function studies revealed that axonal enrichment of Stmn2 is driven by palmitoylation as well as tubulin interaction. Using live imaging, we discover that another Stmn, Stmn3, comigrates with Stmn2-containing vesicles. We also demonstrate that Stmn3 undergoes regulated degradation through dual leucine zipper kinase (DLK)-c-Jun N-terminal kinase signaling. The Stmn2 membrane-targeting domain is both necessary and sufficient for localization to a specific vesicle population and confers sensitivity to DLK-dependent degradation. Our findings reveal a broader role for DLK in tuning the local abundance of palmitoylated Stmns in axon segments. Moreover, palmitoylation is a critical component of Stmn-mediated axon protection, and defining the Stmn2-containing vesicle population will provide important clues toward mechanisms of axon maintenance.
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Affiliation(s)
- Emma J C Thornburg-Suresh
- Interdisciplinary Graduate Program in Neuroscience, University of Iowa, Iowa City, Iowa, USA; Department of Biology, University of Iowa, Iowa City, Iowa, USA
| | | | - Daniel W Summers
- Department of Biology, University of Iowa, Iowa City, Iowa, USA; Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa, USA.
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Yang S, Niou ZX, Enriquez A, LaMar J, Huang JY, Ling K, Jafar-Nejad P, Gilley J, Coleman MP, Tennessen JM, Rangaraju V, Lu HC. NMNAT2 supports vesicular glycolysis via NAD homeostasis to fuel fast axonal transport. RESEARCH SQUARE 2023:rs.3.rs-2859584. [PMID: 37292715 PMCID: PMC10246254 DOI: 10.21203/rs.3.rs-2859584/v1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Background Bioenergetic maladaptations and axonopathy are often found in the early stages of neurodegeneration. Nicotinamide adenine dinucleotide (NAD), an essential cofactor for energy metabolism, is mainly synthesized by Nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2) in CNS neurons. NMNAT2 mRNA levels are reduced in the brains of Alzheimer's, Parkinson's, and Huntington's disease. Here we addressed whether NMNAT2 is required for axonal health of cortical glutamatergic neurons, whose long-projecting axons are often vulnerable in neurodegenerative conditions. We also tested if NMNAT2 maintains axonal health by ensuring axonal ATP levels for axonal transport, critical for axonal function. Methods We generated mouse and cultured neuron models to determine the impact of NMNAT2 loss from cortical glutamatergic neurons on axonal transport, energetic metabolism, and morphological integrity. In addition, we determined if exogenous NAD supplementation or inhibiting a NAD hydrolase, sterile alpha and TIR motif-containing protein 1 (SARM1), prevented axonal deficits caused by NMNAT2 loss. This study used a combination of genetics, molecular biology, immunohistochemistry, biochemistry, fluorescent time-lapse imaging, live imaging with optical sensors, and anti-sense oligos. Results We provide in vivo evidence that NMNAT2 in glutamatergic neurons is required for axonal survival. Using in vivo and in vitro studies, we demonstrate that NMNAT2 maintains the NAD-redox potential to provide "on-board" ATP via glycolysis to vesicular cargos in distal axons. Exogenous NAD+ supplementation to NMNAT2 KO neurons restores glycolysis and resumes fast axonal transport. Finally, we demonstrate both in vitro and in vivo that reducing the activity of SARM1, an NAD degradation enzyme, can reduce axonal transport deficits and suppress axon degeneration in NMNAT2 KO neurons. Conclusion NMNAT2 ensures axonal health by maintaining NAD redox potential in distal axons to ensure efficient vesicular glycolysis required for fast axonal transport.
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Murata H, Yasui Y, Oiso K, Ochi T, Tomonobu N, Yamamoto KI, Kinoshita R, Sakaguchi M. STAT1/3 signaling suppresses axon degeneration and neuronal cell death through regulation of NAD +-biosynthetic and consuming enzymes. Cell Signal 2023; 108:110717. [PMID: 37187216 DOI: 10.1016/j.cellsig.2023.110717] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/17/2023]
Abstract
Nicotinamide adenine dinucleotide (NAD)+-biosynthetic and consuming enzymes are involved in various intracellular events through the regulation of NAD+ metabolism. Recently, it has become clear that alterations in the expression of NAD+-biosynthetic and consuming enzymes contribute to the axonal stability of neurons. We explored soluble bioactive factor(s) that alter the expression of NAD+-metabolizing enzymes and found that cytokine interferon (IFN)-γ increased the expression of nicotinamide nucleotide adenylyltransferase 2 (NMNAT2), an NAD+-biosynthetic enzyme. IFN-γ activated signal transducers and activators of transcription 1 and 3 (STAT1/3) followed by c-Jun N-terminal kinase (JNK) suppression. As a result, STAT1/3 increased the expression of NMNAT2 at both mRNA and protein levels in a dose- and time-dependent manner and, at the same time, suppressed activation of sterile alpha and Toll/interleukin receptor motif-containing 1 (SARM1), an NAD+-consuming enzyme, and increased intracellular NAD+ levels. We examined the protective effect of STAT1/3 signaling against vincristine-mediated cell injury as a model of chemotherapy-induced peripheral neuropathy (CIPN), in which axonal degeneration is involved in disease progression. We found that IFN-γ-mediated STAT1/3 activation inhibited vincristine-induced downregulation of NMNAT2 and upregulation of SARM1 phosphorylation, resulting in modest suppression of subsequent neurite degradation and cell death. These results indicate that STAT1/3 signaling induces NMNAT2 expression while simultaneously suppressing SARM1 phosphorylation, and that both these actions contribute to suppression of axonal degeneration and cell death.
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Affiliation(s)
- Hitoshi Murata
- Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
| | - Yu Yasui
- Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Kazuma Oiso
- Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Toshiki Ochi
- Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Nahoko Tomonobu
- Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Ken-Ichi Yamamoto
- Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Rie Kinoshita
- Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Masakiyo Sakaguchi
- Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
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Thomas S, Enders J, Kaiser A, Rovenstine L, Heslop L, Hauser W, Chadwick A, Wright D. Abnormal intraepidermal nerve fiber density in disease: A scoping review. Front Neurol 2023; 14:1161077. [PMID: 37153658 PMCID: PMC10157176 DOI: 10.3389/fneur.2023.1161077] [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: 02/07/2023] [Accepted: 03/30/2023] [Indexed: 05/10/2023] Open
Abstract
Background Intraepidermal nerve fiber density (IENFD) has become an important biomarker for neuropathy diagnosis and research. The consequences of reduced IENFD can include sensory dysfunction, pain, and a significant decrease in quality of life. We examined the extent to which IENFD is being used as a tool in human and mouse models and compared the degree of fiber loss between diseases to gain a broader understanding of the existing data collected using this common technique. Methods We conducted a scoping review of publications that used IENFD as a biomarker in human and non-human research. PubMed was used to identify 1,004 initial articles that were then screened to select articles that met the criteria for inclusion. Criteria were chosen to standardize publications so they could be compared rigorously and included having a control group, measuring IENFD in a distal limb, and using protein gene product 9.5 (PGP9.5). Results We analyzed 397 articles and collected information related to publication year, the condition studied, and the percent IENFD loss. The analysis revealed that the use of IENFD as a tool has been increasing in both human and non-human research. We found that IENFD loss is prevalent in many diseases, and metabolic or diabetes-related diseases were the most studied conditions in humans and rodents. Our analysis identified 73 human diseases in which IENFD was affected, with 71 reporting IENFD loss and an overall average IENFD change of -47%. We identified 28 mouse and 21 rat conditions, with average IENFD changes of -31.6% and -34.7%, respectively. Additionally, we present data describing sub-analyses of IENFD loss according to disease characteristics in diabetes and chemotherapy treatments in humans and rodents. Interpretation Reduced IENFD occurs in a surprising number of human disease conditions. Abnormal IENFD contributes to important complications, including poor cutaneous vascularization, sensory dysfunction, and pain. Our analysis informs future rodent studies so they may better mirror human diseases impacted by reduced IENFD, highlights the breadth of diseases impacted by IENFD loss, and urges exploration of common mechanisms that lead to substantial IENFD loss as a complication in disease.
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Affiliation(s)
| | | | | | | | | | | | | | - Douglas Wright
- Sensory Nerve Disorder Lab, Department of Anesthesiology, University of Kansas Medical Center, Kansas City, KS, United States
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Fazal SV, Mutschler C, Chen CZ, Turmaine M, Chen CY, Hsueh YP, Ibañez-Grau A, Loreto A, Casillas-Bajo A, Cabedo H, Franklin RJM, Barker RA, Monk KR, Steventon BJ, Coleman MP, Gomez-Sanchez JA, Arthur-Farraj P. SARM1 detection in myelinating glia: sarm1/ Sarm1 is dispensable for PNS and CNS myelination in zebrafish and mice. Front Cell Neurosci 2023; 17:1158388. [PMID: 37091921 PMCID: PMC10113485 DOI: 10.3389/fncel.2023.1158388] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 03/14/2023] [Indexed: 04/08/2023] Open
Abstract
Since SARM1 mutations have been identified in human neurological disease, SARM1 inhibition has become an attractive therapeutic strategy to preserve axons in a variety of disorders of the peripheral (PNS) and central nervous system (CNS). While SARM1 has been extensively studied in neurons, it remains unknown whether SARM1 is present and functional in myelinating glia? This is an important question to address. Firstly, to identify whether SARM1 dysfunction in other cell types in the nervous system may contribute to neuropathology in SARM1 dependent diseases? Secondly, to ascertain whether therapies altering SARM1 function may have unintended deleterious impacts on PNS or CNS myelination? Surprisingly, we find that oligodendrocytes express sarm1 mRNA in the zebrafish spinal cord and that SARM1 protein is readily detectable in rodent oligodendrocytes in vitro and in vivo. Furthermore, activation of endogenous SARM1 in cultured oligodendrocytes induces rapid cell death. In contrast, in peripheral glia, SARM1 protein is not detectable in Schwann cells and satellite glia in vivo and sarm1/Sarm1 mRNA is detected at very low levels in Schwann cells, in vivo, in zebrafish and mouse. Application of specific SARM1 activators to cultured mouse Schwann cells does not induce cell death and nicotinamide adenine dinucleotide (NAD) levels remain unaltered suggesting Schwann cells likely contain no functionally relevant levels of SARM1. Finally, we address the question of whether SARM1 is required for myelination or myelin maintenance. In the zebrafish and mouse PNS and CNS, we show that SARM1 is not required for initiation of myelination and myelin sheath maintenance is unaffected in the adult mouse nervous system. Thus, strategies to inhibit SARM1 function to treat neurological disease are unlikely to perturb myelination in humans.
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Affiliation(s)
- Shaline V. Fazal
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, United Kingdom
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, United Kingdom
| | - Clara Mutschler
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, United Kingdom
| | - Civia Z. Chen
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, United Kingdom
| | - Mark Turmaine
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Chiung-Ya Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Yi-Ping Hsueh
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Andrea Ibañez-Grau
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández, Alicante, Spain
| | - Andrea Loreto
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, United Kingdom
| | - Angeles Casillas-Bajo
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández, Alicante, Spain
- Instituto de Investigación Sanitaria y Biomédica de Alicante (ISABIAL), Alicante, Spain
| | - Hugo Cabedo
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández, Alicante, Spain
- Instituto de Investigación Sanitaria y Biomédica de Alicante (ISABIAL), Alicante, Spain
| | - Robin J. M. Franklin
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, United Kingdom
- Altos Labs - Cambridge Institute of Science, Cambridge, United Kingdom
| | - Roger A. Barker
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, United Kingdom
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, United Kingdom
| | - Kelly R. Monk
- Vollum Institute, Oregon Health & Science University, Portland, OR, United States
| | | | - Michael P. Coleman
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, United Kingdom
| | - Jose A. Gomez-Sanchez
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández, Alicante, Spain
- Instituto de Investigación Sanitaria y Biomédica de Alicante (ISABIAL), Alicante, Spain
- Millennium Nucleus for the Study of Pain (MiNuSPain), Santiago, Chile
| | - Peter Arthur-Farraj
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, United Kingdom
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37
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Sadr Z, Ghasemi A, Rohani M, Alavi A. NMNAT1 and hereditary spastic paraplegia (HSP): expanding the phenotypic spectrum of NMNAT1 variants. Neuromuscul Disord 2023; 33:295-301. [PMID: 36871412 DOI: 10.1016/j.nmd.2023.02.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 02/05/2023] [Accepted: 02/06/2023] [Indexed: 02/10/2023]
Abstract
In the NAD biosynthetic network, the nicotinamide mononucleotide adenylyltransferase (NMNAT) enzyme fuels NAD as a co-substrate for a group of enzymes. Mutations in the nuclear-specific isoform, NMNAT1, have been extensively reported as the cause of Leber congenital amaurosis-type 9 (LCA9). However, there are no reports of NMNAT1 mutations causing neurological disorders by disrupting the maintenance of physiological NAD homeostasis in other types of neurons. In this study, for the first time, the potential association between a NMNAT1 variant and hereditary spastic paraplegia (HSP) is described. Whole-exome sequencing was performed for two affected siblings diagnosed with HSP. Runs of homozygosity (ROH) were detected. The shared variants of the siblings located in the homozygosity blocks were selected. The candidate variant was amplified and Sanger sequenced in the proband and other family members. Homozygous variant c.769G>A:p.(Glu257Lys) in NMNAT1, the most common variant of NMNAT1 in LCA9 patients, located in the ROH of chromosome 1, was detected as a probable disease-causing variant. After detection of the variant in NMNAT1, as a LCA9-causative gene, ophthalmological and neurological re-evaluations were performed. No ophthalmological abnormality was detected and the clinical manifestations of these patients were completely consistent with pure HSP. No NMNAT1 variant had ever been previously reported in HSP patients. However, NMNAT1 variants have been reported in a syndromic form of LCA which is associated with ataxia. In conclusion, our patients expand the clinical spectrum of NMNAT1 variants and represent the first evidence of the probable correlation between NMNAT1 variants and HSP.
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Affiliation(s)
- Zahra Sadr
- Genetics research center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Aida Ghasemi
- Genetics research center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Mohammad Rohani
- Department of Neurology, Iran University of Medical Sciences, Hazrat Rasool Hospital, Tehran, Iran.
| | - Afagh Alavi
- Genetics research center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.
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Li X, Zhang T, Li C, Xu W, Guan Y, Li X, Cheng H, Chen S, Yang B, Liu Y, Ren Z, Song X, Jia Z, Wang Y, Tang J. Electrical stimulation accelerates Wallerian degeneration and promotes nerve regeneration after sciatic nerve injury. Glia 2023; 71:758-774. [PMID: 36484493 DOI: 10.1002/glia.24309] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 11/12/2022] [Accepted: 11/14/2022] [Indexed: 12/13/2022]
Abstract
Following peripheral nerve injury (PNI), Wallerian degeneration (WD) in the distal stump can generate a microenvironment favorable for nerve regeneration. Brief low-frequency electrical stimulation (ES) is an effective treatment for PNI, but the mechanism underlying its effect on WD remains unclear. Therefore, we hypothesized that ES could enhance nerve regeneration by accelerating WD. To verify this hypothesis, we used a rat model of sciatic nerve transection and provided ES at the distal stump of the injured nerve. The injured nerve was then evaluated after 1, 4, 7, 14 and 21 days post injury (dpi). The results showed that ES significantly promoted the degeneration and clearance of axons and myelin, and the dedifferentiation of Schwann cells. It upregulated the expression of BDNF and NGF and increased the number of monocytes and macrophages. Through transcriptome sequencing, we systematically investigated the effect of ES on the molecular processes involved in WD at 4 dpi. Evaluation of nerves bridged using silicone tubing after transection showed that ES accelerated early axonal and vascular regeneration while delaying gastrocnemius atrophy. These results demonstrate that ES promotes nerve regeneration by accelerating WD and upregulating the expression of neurotrophic factors.
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Affiliation(s)
- Xiangling Li
- The School of Medicine, Jinzhou Medical University, Jinzhou, China.,Department of Orthopedics, The Fourth Medical Center of the General Hospital of People's Liberation Army, Beijing, China.,Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China
| | - Tieyuan Zhang
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China
| | - Chaochao Li
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China
| | - Wenjing Xu
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China
| | - Yanjun Guan
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China
| | - Xiaoya Li
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China
| | - Haofeng Cheng
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China.,School of Medicine, Nankai University, Tianjin, China
| | - Shengfeng Chen
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China
| | - Boyao Yang
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China
| | - Yuli Liu
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China
| | - Zhiqi Ren
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China
| | - Xiangyu Song
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China.,School of Medicine, Hebei North University, Zhangjiakou, China
| | - Zhibo Jia
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China.,School of Medicine, Hebei North University, Zhangjiakou, China
| | - Yu Wang
- Department of Orthopedics, The Fourth Medical Center of the General Hospital of People's Liberation Army, Beijing, China.,Institute of Orthopedics, Chinese PLA General Hospital, Beijing Key Lab of Regenerative Medicine in Orthopedics, Key Laboratory of Musculoskeletal Trauma and War Injuries PLA, Beijing, China.,Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Jinshu Tang
- Department of Orthopedics, The Fourth Medical Center of the General Hospital of People's Liberation Army, Beijing, China
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Takenaka T, Ohnishi Y, Yamamoto M, Setoyama D, Kishima H. Glycolytic System in Axons Supplement Decreased ATP Levels after Axotomy of the Peripheral Nerve. eNeuro 2023; 10:ENEURO.0353-22.2023. [PMID: 36894321 PMCID: PMC10035771 DOI: 10.1523/eneuro.0353-22.2023] [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: 08/30/2022] [Revised: 02/04/2023] [Accepted: 02/25/2023] [Indexed: 03/11/2023] Open
Abstract
Wallerian degeneration (WD) occurs in the early stages of numerous neurologic disorders, and clarifying WD pathology is crucial for the advancement of neurologic therapies. ATP is acknowledged as one of the key pathologic substances in WD. The ATP-related pathologic pathways that regulate WD have been defined. The elevation of ATP levels in axon contributes to delay WD and protects axons. However, ATP is necessary for the active processes to proceed WD, given that WD is stringently managed by auto-destruction programs. But little is known about the bioenergetics during WD. In this study, we made sciatic nerve transection models for GO-ATeam2 knock-in rats and mice. We presented the spatiotemporal ATP distribution in the injured axons with in vivo ATP imaging systems, and investigated the metabolic source of ATP in the distal nerve stump. A gradual decrease in ATP levels was observed before the progression of WD. In addition, the glycolytic system and monocarboxylate transporters (MCTs) were activated in Schwann cells following axotomy. Interestingly, in axons, we found the activation of glycolytic system and the inactivation of the tricarboxylic acid (TCA) cycle. Glycolytic inhibitors, 2-deoxyglucose (2-DG) and MCT inhibitors, a-cyano-4-hydroxycinnamic acid (4-CIN) decreased ATP and enhanced WD progression, whereas mitochondrial pyruvate carrier (MPC) inhibitors (MSDC-0160) did not change. Finally, ethyl pyruvate (EP) increased ATP levels and delayed WD. Together, our findings suggest that glycolytic system, both in Schwann cells and axons, is the main source of maintaining ATP levels in the distal nerve stump.
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Affiliation(s)
- Tomofumi Takenaka
- Department of neurosurgery, Graduate School of Medicine, Osaka University, Osaka, 565-0871, Japan
- Department of Research Promotion and Management, National Cerebral and Cardiovascular Center, Osaka, 564-8565, Japan
| | - Yuichiro Ohnishi
- Department of Research Promotion and Management, National Cerebral and Cardiovascular Center, Osaka, 564-8565, Japan
- Department of Neurosurgery, Osaka Gyoumeikan Hospital, Osaka, 554-0012, Japan
| | - Masamichi Yamamoto
- Department of Research Promotion and Management, National Cerebral and Cardiovascular Center, Osaka, 564-8565, Japan
| | - Daiki Setoyama
- Department of Clinical Chemistry and Laboratory Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Haruhiko Kishima
- Department of neurosurgery, Graduate School of Medicine, Osaka University, Osaka, 565-0871, Japan
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40
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Abnormal Intraepidermal Nerve Fiber Density in Disease: A Scoping Review. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.02.08.23285644. [PMID: 36798392 PMCID: PMC9934806 DOI: 10.1101/2023.02.08.23285644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Background Intraepidermal nerve fiber density (IENFD) has become an important biomarker for neuropathy diagnosis and research. The consequences of reduced IENFD can include sensory dysfunction, pain, and a significant decrease in quality of life. We examined the extent to which IENFD is being used as a tool in human and mouse models and compared the degree of fiber loss between diseases to gain a broader understanding of the existing data collected using this common technique. Methods We conducted a scoping review of publications that used IENFD as a biomarker in human and non-human research. PubMed was used to identify 1,004 initial articles that were then screened to select articles that met the criteria for inclusion. Criteria were chosen to standardize publications so they could be compared rigorously and included having a control group, measuring IENFD in a distal limb, and using protein gene product 9.5 (PGP9.5). Results We analyzed 397 articles and collected information related to publication year, the condition studied, and the percent IENFD loss. The analysis revealed that the use of IENFD as a tool has been increasing in both human and non-human research. We found that IENFD loss is prevalent in many diseases, and metabolic or diabetes-related diseases were the most studied conditions in humans and rodents. Our analysis identified 74 human diseases in which IENFD was affected, with 71 reporting IENFD loss and an overall average IENFD change of -47%. We identified 28 mouse and 21 rat conditions, with average IENFD changes of -31.6 % and - 34.7% respectively. Additionally, we present data describing sub-analyses of IENFD loss according to disease characteristics in diabetes and chemotherapy treatments in humans and rodents. Interpretation Reduced IENFD occurs in a surprising number of human disease conditions. Abnormal IENFD contributes to important complications, including poor cutaneous vascularization, sensory dysfunction, and pain. Our analysis informs future rodent studies so they may better mirror human diseases impacted by reduced IENFD, highlights the breadth of diseases impacted by IENFD loss, and urges exploration of common mechanisms that lead to substantial IENFD loss as a complication in disease.
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41
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Li W, Gao M, Hu C, Chen X, Zhou Y. NMNAT2: An important metabolic enzyme affecting the disease progression. Biomed Pharmacother 2023; 158:114143. [PMID: 36528916 DOI: 10.1016/j.biopha.2022.114143] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 12/13/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2) is an evolutionarily conserved nicotinamide adenine dinucleotide (NAD+) synthase located in the cytoplasm and Golgi apparatus. NMNAT2 has an important role in neurodegenerative diseases, malignant tumors, and other diseases that seriously endanger human health. NMNAT2 exerts a neuroprotective function through its NAD synthase activity and chaperone function. Among them, the NMNAT2-NAD+-Sterile alpha and Toll/interleukin-1 receptor motif-containing 1 (SARM1) axis is closely related to Wallerian degeneration. Physical injury or pathological stimulation will cause a decrease in NMNAT2, which activates SARM1, leading to axonal degeneration and the occurrence of amyotrophic lateral sclerosis (ALS), Alzheimer's disease, peripheral neuropathy, and other neurodegenerative diseases. In addition, NMNAT2 exerts a cancer-promoting role in solid tumors, including colorectal cancer, lung cancer, ovarian cancer, and glioma, and is closely related to tumor occurrence and development. This paper reviews the chromosomal and subcellular localization of NMNAT2 and its basic biological functions. We also summarize the NMNAT2-related signal transduction pathway and the role of NMNAT2 in diseases. We aimed to provide a new perspective to comprehensively understand the relationship between NMNAT2 and its associated diseases.
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Affiliation(s)
- Wentao Li
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan 410013, China; Cancer Research Institute, Basic School of Medicine, Central South University, Changsha, Hunan 410078, China
| | - Mengxiang Gao
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan 410013, China; Cancer Research Institute, Basic School of Medicine, Central South University, Changsha, Hunan 410078, China
| | - Chunhui Hu
- Teaching and Research Section of Clinical Nursing, Xiangya Hospital of Central South University, Changsha, Hunan 410013, China
| | - Xiuwen Chen
- Teaching and Research Section of Clinical Nursing, Xiangya Hospital of Central South University, Changsha, Hunan 410013, China.
| | - Yanhong Zhou
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan 410013, China; Cancer Research Institute, Basic School of Medicine, Central South University, Changsha, Hunan 410078, China.
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Tribble JR, Hagström A, Jusseaume K, Lardner E, Wong RCB, Stålhammar G, Williams PA. NAD salvage pathway machinery expression in normal and glaucomatous retina and optic nerve. Acta Neuropathol Commun 2023; 11:18. [PMID: 36681854 PMCID: PMC9867855 DOI: 10.1186/s40478-023-01513-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 01/10/2023] [Indexed: 01/23/2023] Open
Abstract
Glaucoma is the leading cause of irreversible blindness and is a major health and economic burden. Current treatments do not address the neurodegenerative component of glaucoma. In animal models of glaucoma, the capacity to maintain retinal nicotinamide adenine dinucleotide (NAD) pools declines early during disease pathogenesis. Treatment with nicotinamide, an NAD precursor through the NAD salvage pathway, robustly protects against neurodegeneration in a number of glaucoma models and improves vision in existing glaucoma patients. However, it remains unknown in humans what retinal cell types are able to process nicotinamide to NAD and how these are affected in glaucoma. To address this, we utilized publicly available RNA-sequencing data (bulk, single cell, and single nucleus) and antibody labelling in highly preserved enucleated human eyes to identify expression of NAD synthesizing enzyme machinery. This identifies that the neural retina favors expression of the NAD salvage pathway, and that retinal ganglion cells are particularly enriched for these enzymes. NMNAT2, a key terminal enzyme in the salvage pathway, is predominantly expressed in retinal ganglion cell relevant layers of the retina and declines in glaucoma. These findings suggest that human retinal ganglion cells can directly utilize nicotinamide and could maintain a capacity to do so in glaucoma, showing promise for ongoing clinical trials.
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Affiliation(s)
- James R Tribble
- Division of Eye and Vision, Department of Clinical Neuroscience, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Anna Hagström
- Division of Eye and Vision, Department of Clinical Neuroscience, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Kenza Jusseaume
- Division of Eye and Vision, Department of Clinical Neuroscience, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Emma Lardner
- Division of Eye and Vision, Department of Clinical Neuroscience, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Raymond Ching-Bong Wong
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
- Department of Surgery (Ophthalmology), The University of Melbourne, Melbourne, Australia
| | - Gustav Stålhammar
- Division of Eye and Vision, Department of Clinical Neuroscience, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Pete A Williams
- Division of Eye and Vision, Department of Clinical Neuroscience, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden.
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Traumatic axonopathy in spinal tracts after impact acceleration head injury: Ultrastructural observations and evidence of SARM1-dependent axonal degeneration. Exp Neurol 2023; 359:114252. [PMID: 36244414 DOI: 10.1016/j.expneurol.2022.114252] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 10/05/2022] [Accepted: 10/08/2022] [Indexed: 11/09/2022]
Abstract
Traumatic axonal injury (TAI) and the associated axonopathy are common consequences of traumatic brain injury (TBI) and contribute to significant neurological morbidity. It has been previously suggested that TAI activates a highly conserved program of axonal self-destruction known as Wallerian degeneration (WD). In the present study, we utilize our well-established impact acceleration model of TBI (IA-TBI) to characterize the pathology of injured myelinated axons in the white matter tracks traversing the ventral, lateral, and dorsal spinal columns in the mouse and assess the effect of Sterile Alpha and TIR Motif Containing 1 (Sarm1) gene knockout on acute and subacute axonal degeneration and myelin pathology. In silver-stained preparations, we found that IA-TBI results in white matter pathology as well as terminal field degeneration across the rostrocaudal axis of the spinal cord. At the ultrastructural level, we found that traumatic axonopathy is associated with diverse types of axonal and myelin pathology, ranging from focal axoskeletal perturbations and focal disruption of the myelin sheath to axonal fragmentation. Several morphological features such as neurofilament compaction, accumulation of organelles and inclusions, axoskeletal flocculation, myelin degeneration and formation of ovoids are similar to profiles encountered in classical examples of WD. Other profiles such as excess myelin figures and inner tongue evaginations are more typical of chronic neuropathies. Stereological analysis of pathological axonal and myelin profiles in the ventral, lateral, and dorsal columns of the lower cervical cord (C6) segments from wild type and Sarm1 KO mice at 3 and 7 days post IA-TBI (n = 32) revealed an up to 90% reduction in the density of pathological profiles in Sarm1 KO mice after IA-TBI. Protection was evident across all white matter tracts assessed, but showed some variability. Finally, Sarm1 deletion ameliorated the activation of microglia associated with TAI. Our findings demonstrate the presence of severe traumatic axonopathy in multiple ascending and descending long tracts after IA-TBI with features consistent with some chronic axonopathies and models of WD and the across-tract protective effect of Sarm1 deletion.
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Wang S, Zhang Y, Lou J, Yong H, Shan S, Liu Z, Song M, Zhang C, Kou R, Liu Z, Yu W, Zhao X, Song F. The therapeutic potential of berberine chloride against SARM1-dependent axon degeneration in acrylamide-induced neuropathy. Phytother Res 2023; 37:77-88. [PMID: 36054436 DOI: 10.1002/ptr.7594] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 07/11/2022] [Accepted: 08/06/2022] [Indexed: 01/19/2023]
Abstract
Chronic acrylamide (ACR) intoxication causes typical pathology of axon degeneration. Moreover, sterile-α and toll/interleukin 1 receptor motif-containing protein 1 (SARM1), the central executioner of the programmed axonal destruction process under various insults, is up-regulated in ACR neuropathy. However, it remains unclear whether inhibitors targeting SARM1 are effective or not. Among all the pharmacological antagonists, berberine chloride (BBE), a natural phytochemical and the first identified non-competitive inhibitor of SARM1, attracts tremendous attention. Here, we observed the protection of 100 μM BBE against ACR-induced neurites injury (2 mM ACR, 24 hr) in vitro, and further evaluated the neuroprotective effect of BBE (100 mg/kg p.o. three times a week for 4 weeks) in ACR-intoxicated rats (40 mg/kg i.p. three times a week for 4 weeks). The expression of SARM1 was also detected. BBE intervention significantly inhibited the overexpression of SARM1, ameliorated axonal degeneration, alleviated pathological changes in the sciatic nerve and spinal cord, and improved neurobehavioral symptoms in ACR-poisoned rats. Thus, BBE exhibits a strong neuroprotective effect against the SARM1-dependent axon destruction in ACR neuropathy. Meanwhile, our study underscores the need for appropriate inhibitor selection in diverse situations that would benefit from blocking the SARM1-dependent axonal destruction pathway.
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Affiliation(s)
- Shuai Wang
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Yifan Zhang
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Jianwei Lou
- Department of Neurology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Hui Yong
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Shulin Shan
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Zhidan Liu
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Mingxue Song
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Cuiqin Zhang
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.,School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Ruirui Kou
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.,School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Zhaoxiong Liu
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Wenhao Yu
- School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.,Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Xiulan Zhao
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.,School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Fuyong Song
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
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Sarkar A, Kumari N, Mukherjee P. The curious case of SARM1: Dr. Jekyll and Mr. Hyde in cell death and immunity? FEBS J 2023; 290:340-358. [PMID: 34710262 DOI: 10.1111/febs.16256] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 09/21/2021] [Accepted: 10/27/2021] [Indexed: 02/06/2023]
Abstract
Sterile alpha and toll/interleukin-1 receptor motif-containing protein 1 (SARM1) was first identified as a novel ortholog of Drosophila protein CG7915 and was subsequently placed as the fifth member of the human TIR-containing adaptor protein. SARM1 holds a unique position in this family where, unlike other members, it downregulates NFκB activity in response to immunogenic stimulation, interacts with another member of the family, TRIF, to negatively regulate its function, and it also mediates cell death responses. Over the past decade, SARM1 has emerged as one of the primary mediators of programmed axonal degeneration and this robust regulation of axonal degeneration-especially in models of peripheral neuropathy and traumatic injury-makes it an attractive target for therapeutic intervention. The TIR domain of SARM1 possesses an intrinsic NADase activity resulting in cellular energy deficits within the axons, a striking deviation from its other family members of human TLR adaptors. Interestingly, the TIR NADase activity, as seen in SARM1, is also observed in several prokaryotic TIR-containing proteins where they are involved in immune evasion once within the host. Although the immune function of SARM1 is yet to be conclusively discerned, this closeness in function with the prokaryotic TIR-domain containing proteins, places it at an interesting juncture of evolution raising questions about its origin and function in cell death and immunity. In this review, we discuss how a conserved immune adaptor protein like SARM1 switches to a pro-neurodegenerative function and the evolutionarily significance of the process.
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Affiliation(s)
- Ankita Sarkar
- School of Biotechnology, Presidency University, Kolkata, West Bengal, India
| | - Nripa Kumari
- School of Biotechnology, Presidency University, Kolkata, West Bengal, India
| | - Piyali Mukherjee
- School of Biotechnology, Presidency University, Kolkata, West Bengal, India
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46
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Kuribayashi H, Katahira M, Aihara M, Suzuki Y, Watanabe S. Loss-of-function approach using mouse retinal explants showed pivotal roles of Nmnat2 in early and middle stages of retinal development. Mol Biol Cell 2022; 34:ar4. [PMID: 36322391 PMCID: PMC9816650 DOI: 10.1091/mbc.e22-03-0078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Nicotinamide mononucleotide adenylyltransferase (Nmnat) is a class of enzymes with three members (Nmnat1-3). Nmnat1 is in nucleus and associated with Leber congenital amaurosis, a form of early-onset retinal degeneration, while Nmnat2 is in cytoplasm and a well-characterized neuroprotective factor. The differences in their biological roles in the retina are unclear. We performed short hairpin RNA (shRNA)-based loss-of-function analysis of Nmnat2 during mouse retinal development in retinal explant cultures prepared from early (E14.5), middle (E17.5), or late (postnatal day [P]0.5) developmental stages. Nmnat2 has important roles in the survival of retinal cells in the early and middle stages of retinal development. Retinal cell death caused by Nmnat2 knockdown could be partially rescued by supplementation with NAD or nicotinamide mononucleotide (NMN). Survival of retinal cells in the late stage of retinal development was unaffected by Nmnat2, but differentiation of Müller glia was controlled by Nmnat2. RNA-Seq analyses showed perturbation of gene expression patterns by shRNAs specific for Nmnat1 or Nmnat2, but gene ontology analysis did not provide a rational explanation for the phenotype. This study showed that Nmnat2 has multiple developmental stage-dependent roles during mouse retinal development, which were clearly different from those of Nmnat1, suggesting specific roles for Nmnat1 and Nmnat2.
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Affiliation(s)
- Hiroshi Kuribayashi
- Department of Retinal Development and Pathophysiology, The University of Tokyo, Tokyo, Japan,Division of Molecular and Developmental Biology, Institute of Medical Science, The University of Tokyo, Tokyo, Japan,*Address correspondence to: Hiroshi Kuribayashi (); Sumiko Watanabe ()
| | - Miku Katahira
- Division of Molecular and Developmental Biology, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Makoto Aihara
- Department of Ophthalmology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yutaka Suzuki
- Department of Medical Genome Sciences, Graduate School of Frontier Science, The University of Tokyo, Chiba, Japan
| | - Sumiko Watanabe
- Department of Retinal Development and Pathophysiology, The University of Tokyo, Tokyo, Japan,Division of Molecular and Developmental Biology, Institute of Medical Science, The University of Tokyo, Tokyo, Japan,*Address correspondence to: Hiroshi Kuribayashi (); Sumiko Watanabe ()
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Wakhloo D, Oberhauser J, Madira A, Mahajani S. From cradle to grave: neurogenesis, neuroregeneration and neurodegeneration in Alzheimer's and Parkinson's diseases. Neural Regen Res 2022; 17:2606-2614. [PMID: 35662189 PMCID: PMC9165389 DOI: 10.4103/1673-5374.336138] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/16/2021] [Accepted: 12/02/2021] [Indexed: 11/29/2022] Open
Abstract
Two of the most common neurodegenerative disorders - Alzheimer's and Parkinson's diseases - are characterized by synaptic dysfunction and degeneration that culminate in neuronal loss due to abnormal protein accumulation. The intracellular aggregation of hyper-phosphorylated tau and the extracellular aggregation of amyloid beta plaques form the basis of Alzheimer's disease pathology. The major hallmark of Parkinson's disease is the loss of dopaminergic neurons in the substantia nigra pars compacta, following the formation of Lewy bodies, which consists primarily of alpha-synuclein aggregates. However, the discrete mechanisms that contribute to neurodegeneration in these disorders are still poorly understood. Both neuronal loss and impaired adult neurogenesis have been reported in animal models of these disorders. Yet these findings remain subject to frequent debate due to a lack of conclusive evidence in post mortem brain tissue from human patients. While some publications provide significant findings related to axonal regeneration in Alzheimer's and Parkinson's diseases, they also highlight the limitations and obstacles to the development of neuroregenerative therapies. In this review, we summarize in vitro and in vivo findings related to neurogenesis, neuroregeneration and neurodegeneration in the context of Alzheimer's and Parkinson's diseases.
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Affiliation(s)
- Debia Wakhloo
- Deparment of Neuropathology, Stanford University, School of Medicine, Stanford, CA, USA
| | - Jane Oberhauser
- Deparment of Neuropathology, Stanford University, School of Medicine, Stanford, CA, USA
| | - Angela Madira
- Deparment of Neuropathology, Stanford University, School of Medicine, Stanford, CA, USA
| | - Sameehan Mahajani
- Deparment of Neuropathology, Stanford University, School of Medicine, Stanford, CA, USA
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48
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Dai Y, Lin J, Ren J, Zhu B, Wu C, Yu L. NAD + metabolism in peripheral neuropathic pain. Neurochem Int 2022; 161:105435. [PMID: 36273706 DOI: 10.1016/j.neuint.2022.105435] [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: 04/17/2022] [Revised: 10/04/2022] [Accepted: 10/16/2022] [Indexed: 11/07/2022]
Abstract
Nicotinamide adenine dinucleotide (NAD+) is an omnipresent metabolite that participates in redox reactions. Multiple NAD+-consuming enzymes are implicated in numerous biological processes, including transcription, signaling, and cell survival. Multiple pieces of evidence have demonstrated that NAD+-consuming enzymes, including poly(ADP-ribose) polymerases (PARPs), sirtuins (SIRTs), and sterile alpha and TIR motif-containing 1 (SARM1), play major roles in peripheral neuropathic pain of various etiologies. These NAD+ consumers primarily participate in peripheral neuropathic pain via mechanisms such as mitochondrial dysfunction, oxidative stress, and inflammation. Furthermore, NAD+ synthase and nicotinamide phosphoribosyltransferase (NAMPT) have recently been found to contribute to the regulation of pain. Here, we review the evidence indicating the involvement of NAD+ metabolism in the pathological mechanisms of peripheral neuropathic pain. Advanced understanding of the molecular and cellular mechanisms associated with NAD+ in peripheral neuropathic pain will facilitate the development of novel treatment options for diverse types of peripheral neuropathic pain.
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Affiliation(s)
- Yi Dai
- Department of Anesthesiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, 310009, PR China
| | - Jiaqi Lin
- Department of Anesthesiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, 310009, PR China
| | - Jinxuan Ren
- Department of Anesthesiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, 310009, PR China
| | - Bin Zhu
- Department of Anesthesiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, 310009, PR China
| | - Chengwei Wu
- Department of Anesthesiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, 310009, PR China
| | - Lina Yu
- Department of Anesthesiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, 310009, PR China.
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Sato-Yamada Y, Strickland A, Sasaki Y, Bloom J, DiAntonio A, Milbrandt J. A SARM1-mitochondrial feedback loop drives neuropathogenesis in a Charcot-Marie-Tooth disease type 2A rat model. J Clin Invest 2022; 132:e161566. [PMID: 36287202 PMCID: PMC9711878 DOI: 10.1172/jci161566] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 10/11/2022] [Indexed: 11/17/2022] Open
Abstract
Charcot-Marie-Tooth disease type 2A (CMT2A) is an axonal neuropathy caused by mutations in the mitofusin 2 (MFN2) gene. MFN2 mutations result in profound mitochondrial abnormalities, but the mechanism underlying the axonal pathology is unknown. Sterile α and Toll/IL-1 receptor motif-containing 1 (SARM1), the central executioner of axon degeneration, can induce neuropathy and is activated by dysfunctional mitochondria. We tested the role of SARM1 in a rat model carrying a dominant CMT2A mutation (Mfn2H361Y) that exhibits progressive dying-back axonal degeneration, neuromuscular junction (NMJ) abnormalities, muscle atrophy, and mitochondrial abnormalities - all hallmarks of the human disease. We generated Sarm1-KO (Sarm1-/-) and Mfn2H361Y Sarm1 double-mutant rats and found that deletion of Sarm1 rescued axonal, synaptic, muscle, and functional phenotypes, demonstrating that SARM1 was responsible for much of the neuropathology in this model. Despite the presence of mutant MFN2 protein in these double-mutant rats, loss of SARM1 also dramatically suppressed many mitochondrial defects, including the number, size, and cristae density defects of synaptic mitochondria. This surprising finding indicates that dysfunctional mitochondria activated SARM1 and that activated SARM1 fed back on mitochondria to exacerbate the mitochondrial pathology. As such, this work identifies SARM1 inhibition as a therapeutic candidate for the treatment of CMT2A and other neurodegenerative diseases with prominent mitochondrial pathology.
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Affiliation(s)
- Yurie Sato-Yamada
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, USA
- Center for Advanced Oral Science, Niigata University Graduate School of Medical and Dental Science, Niigata City, Japan
| | - Amy Strickland
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Yo Sasaki
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Joseph Bloom
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, USA
- Needleman Center for Neurometabolism and Axonal Therapeutics, St. Louis, Missouri, USA
| | - Aaron DiAntonio
- Needleman Center for Neurometabolism and Axonal Therapeutics, St. Louis, Missouri, USA
- Department of Developmental Biology and
| | - Jeffrey Milbrandt
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, USA
- Needleman Center for Neurometabolism and Axonal Therapeutics, St. Louis, Missouri, USA
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, USA
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50
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Virdee S. An atypical ubiquitin ligase at the heart of neural development and programmed axon degeneration. Neural Regen Res 2022; 17:2347-2350. [PMID: 35535869 PMCID: PMC9120709 DOI: 10.4103/1673-5374.338992] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The degeneration of nerve fibres following injury was first described by Augustus Waller over 170 years ago. Initially assumed to be a passive process, it is now evident that axons respond to insult via regulated cellular signaling events resulting in their programmed degeneration. Pro-survival and pro-degenerative factors have been identified and their regulatory mechanisms are beginning to emerge. The ubiquitin system has been implicated in the pro-degenerative process and a key component is the ubiquitin E3 ligase MYCBP2 (also known as PHR1). Ubiquitin E3 ligases are tasked with the transfer of the small protein modifier ubiquitin to substrates and consist of hundreds of members. They can be classified as single subunit systems or as multi-subunit complexes. Their catalytic domains can also be assigned to three general architectures. Hints that MYCBP2 might not conform to these established formats came to light and it is now clear from biochemical and structural studies that MYCBP2 is indeed an outlier in terms of its modus operandi. Furthermore, the unconventional way in which MYCBP2 transfers ubiquitin to substrates has been linked to neurodevelopmental and pro-degenerative function. Herein, we will summarize these research developments relating to the unusual features of MYCBP2 and postulate therapeutic strategies that prevent Wallerian degeneration. These have exciting potential for providing relief from pathological neuropathies and neurodegenerative diseases.
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Affiliation(s)
- Satpal Virdee
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Scotland, UK
- Correspondence to: Satpal Virdee, .
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