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Stavrou M, Kleopa KA. Gene therapies for CMT neuropathies: from the bench to the clinic. Curr Opin Neurol 2024:00019052-990000000-00173. [PMID: 38873808 DOI: 10.1097/wco.0000000000001289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2024]
Abstract
PURPOSE OF REVIEW Charcot-Marie-Tooth (CMT) neuropathies are rare, genetically heterogeneous and progressive diseases for which there are no approved treatments and their management remains mostly supportive and symptomatic. This review is intended to provide an update on recent developments in gene therapies for different CMT neuropathies. RECENT FINDINGS Increasing knowledge of disease pathomechanisms underlying several CMT types has facilitated the development of promising viral and nonviral gene therapy approaches. Some of these therapies are currently approaching the crucial step of moving from the bench to the clinic, having passed the proof-of-concept stage in rodent models and some also in larger animals. However, questions of optimal delivery route and dose, off-target effects, and possible payload toxicity remain to be clarified for several of these approaches. Furthermore, limited resources, the rarity of most CMT subtypes, and issues of safety and regulatory requirements, create the need for consensus guidelines and optimal clinical trial design. SUMMARY Promising gene therapies have been developed for several CMT neuropathies, with proof-of-principle demonstrated in relevant disease models. Advantages and drawbacks of each approach are discussed and remaining challenges are highlighted. Furthermore, we suggest important parameters that should be considered in order to successfully translate them into the clinic.
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Affiliation(s)
- Marina Stavrou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics
| | - Kleopas A Kleopa
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics
- Center for Neuromuscular Diseases, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
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Abati E, Rizzuti M, Anastasia A, Comi GP, Corti S, Rizzo F. Charcot-Marie-Tooth type 2A in vivo models: Current updates. J Cell Mol Med 2024; 28:e18293. [PMID: 38722298 PMCID: PMC11081012 DOI: 10.1111/jcmm.18293] [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: 01/16/2024] [Revised: 03/13/2024] [Accepted: 03/25/2024] [Indexed: 05/12/2024] Open
Abstract
Charcot-Marie-Tooth type 2A (CMT2A) is an inherited sensorimotor neuropathy associated with mutations within the Mitofusin 2 (MFN2) gene. These mutations impair normal mitochondrial functioning via different mechanisms, disturbing the equilibrium between mitochondrial fusion and fission, of mitophagy and mitochondrial axonal transport. Although CMT2A disease causes a significant disability, no resolutive treatment for CMT2A patients to date. In this context, reliable experimental models are essential to precisely dissect the molecular mechanisms of disease and to devise effective therapeutic strategies. The most commonly used models are either in vitro or in vivo, and among the latter murine models are by far the most versatile and popular. Here, we critically revised the most relevant literature focused on the experimental models, providing an update on the mammalian models of CMT2A developed to date. We highlighted the different phenotypic, histopathological and molecular characteristics, and their use in translational studies for bringing potential therapies from the bench to the bedside. In addition, we discussed limitations of these models and perspectives for future improvement.
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Affiliation(s)
- Elena Abati
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore PoliclinicoMilanItaly
- Department of Pathophysiology and Transplantation, Dino Ferrari CenterUniversità degli Studi di MilanoMilanItaly
| | - Mafalda Rizzuti
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore PoliclinicoMilanItaly
| | - Alessia Anastasia
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore PoliclinicoMilanItaly
| | - Giacomo Pietro Comi
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore PoliclinicoMilanItaly
- Department of Pathophysiology and Transplantation, Dino Ferrari CenterUniversità degli Studi di MilanoMilanItaly
| | - Stefania Corti
- Department of Pathophysiology and Transplantation, Dino Ferrari CenterUniversità degli Studi di MilanoMilanItaly
- Neuromuscular and Rare Diseases Unit, Department of NeuroscienceFondazione IRCCS Ca' Granda Ospedale Maggiore PoliclinicoMilanItaly
| | - Federica Rizzo
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore PoliclinicoMilanItaly
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Alberti C, Rizzo F, Anastasia A, Comi G, Corti S, Abati E. Charcot-Marie-tooth disease type 2A: An update on pathogenesis and therapeutic perspectives. Neurobiol Dis 2024; 193:106467. [PMID: 38452947 DOI: 10.1016/j.nbd.2024.106467] [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: 01/03/2024] [Revised: 03/04/2024] [Accepted: 03/04/2024] [Indexed: 03/09/2024] Open
Abstract
Mutations in the gene encoding MFN2 have been identified as associated with Charcot-Marie-Tooth disease type 2A (CMT2A), a neurological disorder characterized by a broad clinical phenotype involving the entire nervous system. MFN2, a dynamin-like GTPase protein located on the outer mitochondrial membrane, is well-known for its involvement in mitochondrial fusion. Numerous studies have demonstrated its participation in a network crucial for various other mitochondrial functions, including mitophagy, axonal transport, and its controversial role in endoplasmic reticulum (ER)-mitochondria contacts. Considerable progress has been made in the last three decades in elucidating the disease pathogenesis, aided by the generation of animal and cellular models that have been instrumental in studying disease physiology. A review of the literature reveals that, up to now, no definitive pharmacological treatment for any CMT2A variant has been established; nonetheless, recent years have witnessed substantial progress. Many treatment approaches, especially concerning molecular therapy, such as histone deacetylase inhibitors, peptide therapy to increase mitochondrial fusion, the new therapeutic strategies based on MF1/MF2 balance, and SARM1 inhibitors, are currently in preclinical testing. The literature on gene silencing and gene replacement therapies is still limited, except for a recent study by Rizzo et al.(Rizzo et al., 2023), which recently first achieved encouraging results in in vitro and in vivo models of the disease. The near-future goal for these promising therapies is to progress to the stage of clinical translation.
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Affiliation(s)
- Claudia Alberti
- Department of Pathophysiology and Transplantation (DEPT), University of Milan, Milan, Italy
| | - Federica Rizzo
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Alessia Anastasia
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Giacomo Comi
- Department of Pathophysiology and Transplantation (DEPT), University of Milan, Milan, Italy; Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Stefania Corti
- Department of Pathophysiology and Transplantation (DEPT), University of Milan, Milan, Italy; Neuromuscular and Rare Diseases Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Elena Abati
- Department of Pathophysiology and Transplantation (DEPT), University of Milan, Milan, Italy; Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
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Aguilar K, Canal C, Comes G, Díaz-Clavero S, Llanos MA, Quintana A, Sanz E, Hidalgo J. Interleukin-6-elicited chronic neuroinflammation may decrease survival but is not sufficient to drive disease progression in a mouse model of Leigh syndrome. J Inflamm (Lond) 2024; 21:1. [PMID: 38212783 PMCID: PMC10782699 DOI: 10.1186/s12950-023-00369-4] [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: 08/10/2023] [Accepted: 12/01/2023] [Indexed: 01/13/2024] Open
Abstract
BACKGROUND Mitochondrial diseases (MDs) are genetic disorders characterized by dysfunctions in mitochondria. Clinical data suggest that additional factors, beyond genetics, contribute to the onset and progression of this group of diseases, but these influencing factors remain largely unknown. Mounting evidence indicates that immune dysregulation or distress could play a role. Clinical observations have described the co-incidence of infection and the onset of the disease as well as the worsening of symptoms following infection. These findings highlight the complex interactions between MDs and immunity and underscore the need to better understand their underlying relationships. RESULTS We used Ndufs4 KO mice, a well-established mouse model of Leigh syndrome (one of the most relevant MDs), to test whether chronic induction of a neuroinflammatory state in the central nervous system before the development of neurological symptoms would affect both the onset and progression of the disease in Ndufs4 KO mice. To this aim, we took advantage of the GFAP-IL6 mouse, which overexpresses interleukin-6 (IL-6) in astrocytes and produces chronic glial reactivity, by generating a mouse line with IL-6 overexpression and NDUFS4 deficiency. IL-6 overexpression aggravated the mortality of female Ndufs4 KO mice but did not alter the main motor and respiratory phenotypes measured in any sex. Interestingly, an abnormal region-dependent microglial response to IL-6 overexpression was observed in Ndufs4 KO mice compared to controls. CONCLUSION Overall, our data indicate that chronic neuroinflammation may worsen the disease in Ndufs4 KO female mice, but not in males, and uncovers an abnormal microglial response due to OXPHOS dysfunction, which may have implications for our understanding of the effect of OXPHOS dysfunction in microglia.
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Affiliation(s)
- Kevin Aguilar
- Department of Cellular Biology, Physiology and Immunology, Animal Physiology Unit, Faculty of Biosciences, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, 08193
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
- Present address: Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
| | - Carla Canal
- Department of Cellular Biology, Physiology and Immunology, Animal Physiology Unit, Faculty of Biosciences, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, 08193
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Gemma Comes
- Department of Cellular Biology, Physiology and Immunology, Animal Physiology Unit, Faculty of Biosciences, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, 08193
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Sandra Díaz-Clavero
- Department of Cellular Biology, Physiology and Immunology, Animal Physiology Unit, Faculty of Biosciences, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, 08193
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
- Present address: Dementia Research Institute, Imperial College London, London, UK
| | - Maria Angeles Llanos
- Department of Cellular Biology, Physiology and Immunology, Animal Physiology Unit, Faculty of Biosciences, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, 08193
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Albert Quintana
- Department of Cellular Biology, Physiology and Immunology, Animal Physiology Unit, Faculty of Biosciences, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, 08193
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Elisenda Sanz
- Department of Cellular Biology, Physiology and Immunology, Animal Physiology Unit, Faculty of Biosciences, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, 08193.
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
| | - Juan Hidalgo
- Department of Cellular Biology, Physiology and Immunology, Animal Physiology Unit, Faculty of Biosciences, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain, 08193.
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
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Fan C, Wang JX, Xiong ZE, Hu SS, Zhou AJ, Yuan D, Zhang CC, Zhou ZY, Wang T. Saponins from Panax japonicus improve neuronal mitochondrial injury of aging rats. PHARMACEUTICAL BIOLOGY 2023; 61:1401-1412. [PMID: 37667488 PMCID: PMC10484050 DOI: 10.1080/13880209.2023.2244532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 06/16/2023] [Accepted: 07/31/2023] [Indexed: 09/06/2023]
Abstract
CONTEXT Panax japonicus is the dried rhizome of Panax japonicus C.A. Mey. (Araliaceae). Saponins from Panax japonicus (SPJ) exhibit anti-oxidative and anti-aging effects. OBJECTIVE We evaluated the neuroprotective effects of SPJ on aging rats. MATERIALS AND METHODS Sprague-Dawley rats (18-months-old) were randomly divided into aging and SPJ groups (n = 8). Five-month-old rats were taken as the adult control (n = 8). The rats were fed a normal chow diet or the SPJ-containing diet (10 or 30 mg/kg) for 4 months. An in vitro model was established by d-galactose (d-Gal) in the SH-SY5Y cell line and pretreated with SPJ (25 and 50 µg/mL). The neuroprotection of SPJ was evaluated via Nissl staining, flow cytometry, transmission electron microscopy and Western blotting in vivo and in vitro. RESULTS SPJ improved the neuronal degeneration and mitochondrial morphology that are associated with aging. Meanwhile, SPJ up-regulated the protein levels of mitofusin 2 (Mfn2) and optic atrophy 1 (Opa1) and down-regulated the protein level of dynamin-like protein 1 (Drp1) in the hippocampus of aging rats (p < 0.05 or p < 0.01 vs. 22 M). The in vitro studies also demonstrated that SPJ attenuated d-Gal-induced cell senescence concomitant with the improvement in mitochondrial function; SPJ, also up-regulated the Mfn2 and Opa1 protein levels, whereas the Drp1 protein level (p < 0.05 or p < 0.01 vs. d-Gal group) was down-regulated. DISCUSSION AND CONCLUSIONS Further research on the elderly population will contribute to the development and utilization of SPJ for the treatment of neurodegenerative disorders.
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Affiliation(s)
- Cheng Fan
- Institute of Pharmaceutical Process, Academy of Nutrition and Health Hubei Province Key Laboratory of Occupational Hazard Identification and Control School of Medicine, Wuhan University of Science and TechnologyWuhan, China
| | - Jin-Xin Wang
- College of Medical Science, Three Gorges University, Yichang, Hubei, China
| | - Zhang-E. Xiong
- Department of Gastroenterology, Wuhan Third Hospital, Wuhan, China
| | - Shan-Shan Hu
- College of Medical Science, Three Gorges University, Yichang, Hubei, China
| | - Ao-Jia Zhou
- Institute of Pharmaceutical Process, Academy of Nutrition and Health Hubei Province Key Laboratory of Occupational Hazard Identification and Control School of Medicine, Wuhan University of Science and TechnologyWuhan, China
| | - Ding Yuan
- College of Medical Science, Three Gorges University, Yichang, Hubei, China
| | - Chang-Cheng Zhang
- College of Medical Science, Three Gorges University, Yichang, Hubei, China
| | - Zhi-Yong Zhou
- College of Medical Science, Three Gorges University, Yichang, Hubei, China
| | - Ting Wang
- Institute of Pharmaceutical Process, Academy of Nutrition and Health Hubei Province Key Laboratory of Occupational Hazard Identification and Control School of Medicine, Wuhan University of Science and TechnologyWuhan, China
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Luo B. Insights into the advances in therapeutic drugs for neuroinflammation-related diseases. Int J Neurosci 2023:1-26. [PMID: 37722706 DOI: 10.1080/00207454.2023.2260088] [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: 08/11/2023] [Accepted: 09/12/2023] [Indexed: 09/20/2023]
Abstract
Studies have shown that neurodegenerative diseases such as AD and PD are related to neuroinflammation. Neuroinflammation is a common inflammatory condition that can lead to a variety of dysfunction in the body. At present, it is no medications specifically approved to prevent or cure neuroinflammation, so even though many drugs can temporarily control the neurological symptoms of neuroinflammation, but no one can reverse the progress of neuroinflammation, let al.one completely cure neuroinflammation. Therefore, it is urgent to develop new drug development for neuroinflammation treatment. In this review, we highlight the therapeutic advancement in the field of neurodegenerative disorders, by focusing on the impact of neuroinflammation treatment has on these conditions, and the effective drugs for the treatment of neuroinflammation and neurodegenerative diseases and their latest research progress are reviewed according to the related signaling pathway, as well as the prospect of their clinical application is also discussed. The purpose of this review is to enable specialists to better understand the mechanisms underlying neuroinflammation and anti-inflammatory drugs, promote the development of therapeutic drugs for neuroinflammation and neurodegenerative diseases, and further provide therapeutic references for clinical neurologists.
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Affiliation(s)
- Bozhi Luo
- School of Basic Medicine, Hengyang Medical College, University of South China, Hengyang, China
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Kagiava A, Karaiskos C, Lapathitis G, Heslegrave A, Sargiannidou I, Zetterberg H, Bosch A, Kleopa KA. Gene replacement therapy in two Golgi-retained CMT1X mutants before and after the onset of demyelinating neuropathy. Mol Ther Methods Clin Dev 2023; 30:377-393. [PMID: 37645436 PMCID: PMC10460951 DOI: 10.1016/j.omtm.2023.07.011] [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: 01/03/2023] [Accepted: 07/31/2023] [Indexed: 08/31/2023]
Abstract
X-linked Charcot-Marie-Tooth disease type 1 (CMT1X) is a demyelinating neuropathy resulting from loss-of-function mutations affecting the GJB1/connexin 32 (Cx32) gene. We previously showed functional and morphological improvement in Gjb1-null mice following AAV9-mediated delivery of human Cx32 driven by the myelin protein zero (Mpz) promoter in Schwann cells. However, CMT1X mutants may interfere with virally delivered wild-type (WT) Cx32. To confirm the efficacy of this vector also in the presence of CMT1X mutants, we delivered AAV9-Mpz-GJB1 by lumbar intrathecal injection in R75W/Gjb1-null and N175D/Gjb1-null transgenic lines expressing Golgi-retained mutations, before and after the onset of the neuropathy. Widespread expression of virally delivered Cx32 was demonstrated in both genotypes. Re-establishment of WT Cx32 function resulted in improved muscle strength and increased sciatic nerve motor conduction velocities in all treated groups from both mutant lines when treated before as well as after the onset of the neuropathy. Furthermore, morphological analysis showed improvement of myelination and reduction of inflammation in lumbar motor roots and peripheral nerves. In conclusion, this study provides proof of principle for a clinically translatable gene therapy approach to treat CMT1X before and after the onset of the neuropathy, even in the presence of endogenously expressed Golgi-retained Cx32 mutants.
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Affiliation(s)
- Alexia Kagiava
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine, 2371 Nicosia, Cyprus
| | - Christos Karaiskos
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine, 2371 Nicosia, Cyprus
| | - George Lapathitis
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine, 2371 Nicosia, Cyprus
| | - Amanda Heslegrave
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London WC1E 6BT, UK
- UK Dementia Research Institute at UCL, London WC1E 6BT, UK
| | - Irene Sargiannidou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine, 2371 Nicosia, Cyprus
| | - Henrik Zetterberg
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London WC1E 6BT, UK
- UK Dementia Research Institute at UCL, London WC1E 6BT, UK
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, 40530 Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, 40530 Mölndal, Sweden
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53792, USA
| | - Assumpció Bosch
- Department of Biochemistry & Molecular Biology, Institute of Neurosciences, Universitat Autònoma de Barcelona, 08193 Bellatera, Spain
- Unitat Mixta UAB-VHIR, Vall d'Hebron Institut de Recerca (VHIR), 08035 Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, 028029 Madrid, Spain
| | - Kleopas A. Kleopa
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine, 2371 Nicosia, Cyprus
- Center for Neuromuscular Disorders, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine, 2371 Nicosia, Cyprus
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Stavropoulos F, Georgiou E, Schiza N, Bell S, Baloh RH, Kleopa KA, Sargiannidou I. Mitofusin 1 overexpression rescues the abnormal mitochondrial dynamics caused by the Mitofusin 2 K357T mutation in vitro. J Peripher Nerv Syst 2023; 28:329-340. [PMID: 37220142 DOI: 10.1111/jns.12564] [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: 02/06/2023] [Revised: 05/12/2023] [Accepted: 05/19/2023] [Indexed: 05/25/2023]
Abstract
BACKGROUND AND AIMS Mitofusin 1 (MFN1) and MFN2 are outer mitochondrial membrane fusogenic proteins regulating mitochondrial network morphology. MFN2 mutations cause Charcot-Marie-Tooth type 2A (CMT2A), an axonal neuropathy characterized by mitochondrial fusion defects, which in the case of a GTPase domain mutant, were rescued following wild-type MFN1/2 (MFN1/2WT ) overexpression. In this study, we compared the therapeutic efficiency between MFN1WT and MFN2WT overexpression in correcting mitochondrial defects induced by the novel MFN2K357T mutation located in the highly conserved R3 region. METHODS Constructs expressing either MFN2K357T , MFN2WT , or MFN1WT under the ubiquitous chicken β-actin hybrid (CBh) promoter were generated. Flag or myc tag was used for their detection. Differentiated SH-SY5Y cells were single transfected with MFN1WT , MFN2WT , or MFN2K357T , as well as double transfected with MFN2K357T /MFN2WT or MFN2K357T /MFN1WT . RESULTS SH-SY5Y cells transfected with MFN2K357T exhibited severe perinuclear mitochondrial clustering with axon-like processes devoid of mitochondria. Single transfection with MFN1WT resulted in a more interconnected mitochondrial network than transfection with MFN2WT , accompanied by mitochondrial clusters. Double transfection of MFN2K357T with either MFN1WT or MFN2WT resolved the mutant-induced mitochondrial clusters and led to detectable mitochondria throughout the axon-like processes. MFN1WT showed higher efficacy than MFN2WT in rescuing these defects. INTERPRETATION These results further demonstrate the higher potential of MFN1WT over MFN2WT overexpression to rescue CMT2A-induced mitochondrial network abnormalities due to mutations outside the GTPase domain. This higher phenotypic rescue conferred by MFN1WT , possibly due to its higher mitochondrial fusogenic ability, may be applied to different CMT2A cases regardless of the MFN2 mutation type.
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Affiliation(s)
- Filippos Stavropoulos
- Department of Neuroscience, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Elena Georgiou
- Department of Neuroscience, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Natasa Schiza
- Department of Neuroscience, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Shaughn Bell
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Robert H Baloh
- Global Head of Neuroscience, Novartis Institutes for BioMedical Research, Cambridge, Massachusetts, USA
| | - Kleopas A Kleopa
- Department of Neuroscience, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
- Center for Neuromuscular Disorders and Center for Multiple Sclerosis and Related Disorders, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Irene Sargiannidou
- Department of Neuroscience, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
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Hanaford A, Johnson SC. The immune system as a driver of mitochondrial disease pathogenesis: a review of evidence. Orphanet J Rare Dis 2022; 17:335. [PMID: 36056365 PMCID: PMC9438277 DOI: 10.1186/s13023-022-02495-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Accepted: 08/15/2022] [Indexed: 12/04/2022] Open
Abstract
Background Genetic mitochondrial diseases represent a significant challenge to human health. These diseases are extraordinarily heterogeneous in clinical presentation and genetic origin, and often involve multi-system disease with severe progressive symptoms. Mitochondrial diseases represent the most common cause of inherited metabolic disorders and one of the most common causes of inherited neurologic diseases, yet no proven therapeutic strategies yet exist. The basic cell and molecular mechanisms underlying the pathogenesis of mitochondrial diseases have not been resolved, hampering efforts to develop therapeutic agents. Main body In recent pre-clinical work, we have shown that pharmacologic agents targeting the immune system can prevent disease in the Ndufs4(KO) model of Leigh syndrome, indicating that the immune system plays a causal role in the pathogenesis of at least this form of mitochondrial disease. Intriguingly, a number of case reports have indicated that immune-targeting therapeutics may be beneficial in the setting of genetic mitochondrial disease. Here, we summarize clinical and pre-clinical evidence suggesting a key role for the immune system in mediating the pathogenesis of at least some forms of genetic mitochondrial disease. Conclusions Significant clinical and pre-clinical evidence indicates a key role for the immune system as a significant in the pathogenesis of at least some forms of genetic mitochondrial disease.
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Affiliation(s)
- Allison Hanaford
- Center for Integrative Brain Research, Seattle Children's Research Institute, 1900 9th Ave., JMB-925, Seattle, WA, 98101, USA
| | - Simon C Johnson
- Center for Integrative Brain Research, Seattle Children's Research Institute, 1900 9th Ave., JMB-925, Seattle, WA, 98101, USA. .,Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA. .,Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, USA. .,Department of Neurology, University of Washington, Seattle, WA, USA.
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