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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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2
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Hernandez-Resendiz S, Prakash A, Loo SJ, Semenzato M, Chinda K, Crespo-Avilan GE, Dam LC, Lu S, Scorrano L, Hausenloy DJ. Targeting mitochondrial shape: at the heart of cardioprotection. Basic Res Cardiol 2023; 118:49. [PMID: 37955687 PMCID: PMC10643419 DOI: 10.1007/s00395-023-01019-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/24/2023] [Accepted: 10/25/2023] [Indexed: 11/14/2023]
Abstract
There remains an unmet need to identify novel therapeutic strategies capable of protecting the myocardium against the detrimental effects of acute ischemia-reperfusion injury (IRI), to reduce myocardial infarct (MI) size and prevent the onset of heart failure (HF) following acute myocardial infarction (AMI). In this regard, perturbations in mitochondrial morphology with an imbalance in mitochondrial fusion and fission can disrupt mitochondrial metabolism, calcium homeostasis, and reactive oxygen species production, factors which are all known to be critical determinants of cardiomyocyte death following acute myocardial IRI. As such, therapeutic approaches directed at preserving the morphology and functionality of mitochondria may provide an important strategy for cardioprotection. In this article, we provide an overview of the alterations in mitochondrial morphology which occur in response to acute myocardial IRI, and highlight the emerging therapeutic strategies for targeting mitochondrial shape to preserve mitochondrial function which have the future therapeutic potential to improve health outcomes in patients presenting with AMI.
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Affiliation(s)
- Sauri Hernandez-Resendiz
- Duke-NUS Medical School, Cardiovascular and Metabolic Disorders Programme, Singapore, Singapore
- National Heart Centre Singapore, National Heart Research Institute Singapore, Singapore, Singapore
| | - Aishwarya Prakash
- Duke-NUS Medical School, Cardiovascular and Metabolic Disorders Programme, Singapore, Singapore
- National Heart Centre Singapore, National Heart Research Institute Singapore, Singapore, Singapore
| | - Sze Jie Loo
- Duke-NUS Medical School, Cardiovascular and Metabolic Disorders Programme, Singapore, Singapore
- National Heart Centre Singapore, National Heart Research Institute Singapore, Singapore, Singapore
| | | | - Kroekkiat Chinda
- Department of Physiology, Faculty of Medical Science, Naresuan University, Phitsanulok, Thailand
| | - Gustavo E Crespo-Avilan
- Duke-NUS Medical School, Cardiovascular and Metabolic Disorders Programme, Singapore, Singapore
- National Heart Centre Singapore, National Heart Research Institute Singapore, Singapore, Singapore
| | - Linh Chi Dam
- Duke-NUS Medical School, Cardiovascular and Metabolic Disorders Programme, Singapore, Singapore
- National Heart Centre Singapore, National Heart Research Institute Singapore, Singapore, Singapore
| | - Shengjie Lu
- Duke-NUS Medical School, Cardiovascular and Metabolic Disorders Programme, Singapore, Singapore
- National Heart Centre Singapore, National Heart Research Institute Singapore, Singapore, Singapore
| | - Luca Scorrano
- Veneto Institute of Molecular Medicine, Padova, Italy
- Department of Biology, University of Padova, Padova, Italy
| | - Derek J Hausenloy
- Duke-NUS Medical School, Cardiovascular and Metabolic Disorders Programme, Singapore, Singapore.
- National Heart Centre Singapore, National Heart Research Institute Singapore, Singapore, Singapore.
- National University Singapore, Yong Loo Lin School of Medicine, Singapore, Singapore.
- University College London, The Hatter Cardiovascular Institute, London, UK.
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3
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Franco A, Li J, Kelly DP, Hershberger RE, Marian AJ, Lewis RM, Song M, Dang X, Schmidt AD, Mathyer ME, Edwards JR, Strong CDG, Dorn GW. A human mitofusin 2 mutation can cause mitophagic cardiomyopathy. eLife 2023; 12:e84235. [PMID: 37910431 PMCID: PMC10619978 DOI: 10.7554/elife.84235] [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: 10/16/2022] [Accepted: 09/26/2023] [Indexed: 11/03/2023] Open
Abstract
Cardiac muscle has the highest mitochondrial density of any human tissue, but mitochondrial dysfunction is not a recognized cause of isolated cardiomyopathy. Here, we determined that the rare mitofusin (MFN) 2 R400Q mutation is 15-20× over-represented in clinical cardiomyopathy, whereas this specific mutation is not reported as a cause of MFN2 mutant-induced peripheral neuropathy, Charcot-Marie-Tooth disease type 2A (CMT2A). Accordingly, we interrogated the enzymatic, biophysical, and functional characteristics of MFN2 Q400 versus wild-type and CMT2A-causing MFN2 mutants. All MFN2 mutants had impaired mitochondrial fusion, the canonical MFN2 function. Compared to MFN2 T105M that lacked catalytic GTPase activity and exhibited normal activation-induced changes in conformation, MFN2 R400Q and M376A had normal GTPase activity with impaired conformational shifting. MFN2 R400Q did not suppress mitochondrial motility, provoke mitochondrial depolarization, or dominantly suppress mitochondrial respiration like MFN2 T105M. By contrast to MFN2 T105M and M376A, MFN2 R400Q was uniquely defective in recruiting Parkin to mitochondria. CRISPR editing of the R400Q mutation into the mouse Mfn2 gene induced perinatal cardiomyopathy with no other organ involvement; knock-in of Mfn2 T105M or M376V did not affect the heart. RNA sequencing and metabolomics of cardiomyopathic Mfn2 Q/Q400 hearts revealed signature abnormalities recapitulating experimental mitophagic cardiomyopathy. Indeed, cultured cardiomyoblasts and in vivo cardiomyocytes expressing MFN2 Q400 had mitophagy defects with increased sensitivity to doxorubicin. MFN2 R400Q is the first known natural mitophagy-defective MFN2 mutant. Its unique profile of dysfunction evokes mitophagic cardiomyopathy, suggesting a mechanism for enrichment in clinical cardiomyopathy.
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Affiliation(s)
- Antonietta Franco
- Department of Internal Medicine, Pharmacogenomics, Washington University School of MedicineSt LouisUnited States
| | - Jiajia Li
- Department of Internal Medicine, Pharmacogenomics, Washington University School of MedicineSt LouisUnited States
| | - Daniel P Kelly
- Department of Medicine, Cardiovascular Institute, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | - Ray E Hershberger
- Department of Internal Medicine, Divisions of Human Genetics and Cardiovascular Medicine, Ohio State UniversityColumbusUnited States
| | - Ali J Marian
- Center for Cardiovascular Genetic Research, University of Texas Health Science Center at HoustonHoustonUnited States
| | - Renate M Lewis
- Department of Neurology, Washington University School of MedicineSt. LouisUnited States
| | - Moshi Song
- Department of Internal Medicine, Pharmacogenomics, Washington University School of MedicineSt LouisUnited States
| | - Xiawei Dang
- Department of Internal Medicine, Pharmacogenomics, Washington University School of MedicineSt LouisUnited States
| | - Alina D Schmidt
- Department of Internal Medicine (Dermatology), Washington University School of MedicineSt. LouisUnited States
| | - Mary E Mathyer
- Department of Internal Medicine (Dermatology), Washington University School of MedicineSt. LouisUnited States
| | - John R Edwards
- Department of Internal Medicine, Pharmacogenomics, Washington University School of MedicineSt LouisUnited States
| | - Cristina de Guzman Strong
- Department of Internal Medicine (Dermatology), Washington University School of MedicineSt. LouisUnited States
| | - Gerald W Dorn
- Department of Internal Medicine, Pharmacogenomics, Washington University School of MedicineSt LouisUnited States
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Hinton A, Katti P, Christensen TA, Mungai M, Shao J, Zhang L, Trushin S, Alghanem A, Jaspersen A, Geroux RE, Neikirk K, Biete M, Lopez EG, Shao B, Vue Z, Vang L, Beasley HK, Marshall AG, Stephens D, Damo S, Ponce J, Bleck CKE, Hicsasmaz I, Murray SA, Edmonds RAC, Dajles A, Koo YD, Bacevac S, Salisbury JL, Pereira RO, Glancy B, Trushina E, Abel ED. A Comprehensive Approach to Sample Preparation for Electron Microscopy and the Assessment of Mitochondrial Morphology in Tissue and Cultured Cells. Adv Biol (Weinh) 2023; 7:e2200202. [PMID: 37140138 PMCID: PMC10615857 DOI: 10.1002/adbi.202200202] [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] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 03/24/2023] [Indexed: 05/05/2023]
Abstract
Mitochondria respond to metabolic demands of the cell and to incremental damage, in part, through dynamic structural changes that include fission (fragmentation), fusion (merging of distinct mitochondria), autophagic degradation (mitophagy), and biogenic interactions with the endoplasmic reticulum (ER). High resolution study of mitochondrial structural and functional relationships requires rapid preservation of specimens to reduce technical artifacts coupled with quantitative assessment of mitochondrial architecture. A practical approach for assessing mitochondrial fine structure using two dimensional and three dimensional high-resolution electron microscopy is presented, and a systematic approach to measure mitochondrial architecture, including volume, length, hyperbranching, cristae morphology, and the number and extent of interaction with the ER is described. These methods are used to assess mitochondrial architecture in cells and tissue with high energy demand, including skeletal muscle cells, mouse brain tissue, and Drosophila muscles. The accuracy of assessment is validated in cells and tissue with deletion of genes involved in mitochondrial dynamics.
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Affiliation(s)
- Antentor Hinton
- Department of Internal Medicine, University of Iowa - Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA, 52242, USA
- Fraternal Order of Eagles Diabetes Research Center, 169 Newton Rd, Iowa City, IA, 52242, USA
- Microscopy and Cell Analysis Core Facility, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
- Department of Molecular Physiology and Biophysics, Vanderbilt University, 2201 West End Ave, Nashville, TN, 37235, USA
| | - Prasanna Katti
- National Heart, Lung, and Blood Institute, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, USA
| | - Trace A Christensen
- Microscopy and Cell Analysis Core Facility, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Margaret Mungai
- Department of Internal Medicine, University of Iowa - Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA, 52242, USA
- Fraternal Order of Eagles Diabetes Research Center, 169 Newton Rd, Iowa City, IA, 52242, USA
| | - Jianqiang Shao
- Central Microscopy Research Facility, University of Iowa, Iowa City, IA, 52242, USA
| | - Liang Zhang
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Sergey Trushin
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Ahmad Alghanem
- Department of Internal Medicine, Division of Cardiology, Washington University in St. Louis, 1 Brookings Dr, St. Louis, MO, 63130, USA
- Eastern Region, King Abdullah International Medical Research Center, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11481, Al Hasa, Saudi Arabia
| | - Adam Jaspersen
- Microscopy and Cell Analysis Core Facility, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Rachel E Geroux
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Kit Neikirk
- College of Natural and Health Sciences, University of Hawaii at Hilo, 200 West Kawili St, Hilo, HI, 96720, USA
| | - Michelle Biete
- College of Natural and Health Sciences, University of Hawaii at Hilo, 200 West Kawili St, Hilo, HI, 96720, USA
| | - Edgar Garza Lopez
- Department of Internal Medicine, University of Iowa - Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA, 52242, USA
| | - Bryanna Shao
- Department of Molecular Physiology and Biophysics, Vanderbilt University, 2201 West End Ave, Nashville, TN, 37235, USA
| | - Zer Vue
- Department of Molecular Physiology and Biophysics, Vanderbilt University, 2201 West End Ave, Nashville, TN, 37235, USA
| | - Larry Vang
- Department of Molecular Physiology and Biophysics, Vanderbilt University, 2201 West End Ave, Nashville, TN, 37235, USA
| | - Heather K Beasley
- Department of Molecular Physiology and Biophysics, Vanderbilt University, 2201 West End Ave, Nashville, TN, 37235, USA
- Department of Biochemistry, Cancer Biology, Neuroscience and Pharmacology, School of Graduate Studies and Research, Meharry Medical College, Nashville, TN, 37208, USA
| | - Andrea G Marshall
- Department of Molecular Physiology and Biophysics, Vanderbilt University, 2201 West End Ave, Nashville, TN, 37235, USA
| | - Dominique Stephens
- Department of Molecular Physiology and Biophysics, Vanderbilt University, 2201 West End Ave, Nashville, TN, 37235, USA
- Department of Life and Physical Sciences, Fisk University, Nashville, TN, 37208, USA
| | - Steven Damo
- Department of Life and Physical Sciences, Fisk University, Nashville, TN, 37208, USA
| | - Jessica Ponce
- School of Medicine, University of Utah, 30 N 1900 E, Salt Lake City, UT, 84132, USA
| | - Christopher K E Bleck
- National Heart, Lung, and Blood Institute, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, USA
| | - Innes Hicsasmaz
- Department of Internal Medicine, University of Iowa - Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA, 52242, USA
- Fraternal Order of Eagles Diabetes Research Center, 169 Newton Rd, Iowa City, IA, 52242, USA
| | - Sandra A Murray
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA, 15206, USA
| | - Ranthony A C Edmonds
- Department of Mathematics, Ohio State University, 281 W Lane Ave, Columbus, OH, 43210, USA
| | - Andres Dajles
- Department of Internal Medicine, University of Iowa - Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA, 52242, USA
| | - Young Do Koo
- Department of Internal Medicine, University of Iowa - Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA, 52242, USA
- Fraternal Order of Eagles Diabetes Research Center, 169 Newton Rd, Iowa City, IA, 52242, USA
| | - Serif Bacevac
- Department of Internal Medicine, University of Iowa - Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA, 52242, USA
- Fraternal Order of Eagles Diabetes Research Center, 169 Newton Rd, Iowa City, IA, 52242, USA
| | - Jeffrey L Salisbury
- Microscopy and Cell Analysis Core Facility, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Renata O Pereira
- Department of Internal Medicine, University of Iowa - Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA, 52242, USA
- Fraternal Order of Eagles Diabetes Research Center, 169 Newton Rd, Iowa City, IA, 52242, USA
| | - Brian Glancy
- National Heart, Lung, and Blood Institute, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, USA
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, USA
| | - Eugenia Trushina
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - E Dale Abel
- Department of Internal Medicine, University of Iowa - Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA, 52242, USA
- Fraternal Order of Eagles Diabetes Research Center, 169 Newton Rd, Iowa City, IA, 52242, USA
- Department of Medicine, UCLA, 757 Westwood Plaza, Suite 7236, David Geffen School of Medicine, Los Angeles, CA, 90095, USA
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5
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Ying Z, Ye N, Ma Q, Chen F, Li N, Zhen X. Targeted to neuronal organelles for CNS drug development. Adv Drug Deliv Rev 2023; 200:115025. [PMID: 37516410 DOI: 10.1016/j.addr.2023.115025] [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: 04/30/2023] [Revised: 07/07/2023] [Accepted: 07/26/2023] [Indexed: 07/31/2023]
Abstract
Significant evidences indicate that sub-cellular organelle dynamics is critical for both physiological and pathological events and therefore may be attractive drug targets displaying great therapeutic potential. Although the basic biological mechanism underlying the dynamics of intracellular organelles has been extensively studied, relative drug development is still limited. In the present review, we show that due to the development of technical advanced imaging tools, especially live cell imaging methods, intracellular organelle dynamics (including mitochondrial dynamics and membrane contact sites) can be dissected at the molecular level. Based on these identified molecular targets, we review and discuss the potential of drug development to target organelle dynamics, especially mitochondria dynamics and ER-organelle membrane contact dynamics, in the central nervous system for treating human diseases, including neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease and amyotrophic lateral sclerosis.
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Affiliation(s)
- Zheng Ying
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China.
| | - Na Ye
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Qilian Ma
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Fan Chen
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Ningning Li
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Xuechu Zhen
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China.
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6
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Muñoz JP, Basei FL, Rojas ML, Galvis D, Zorzano A. Mechanisms of Modulation of Mitochondrial Architecture. Biomolecules 2023; 13:1225. [PMID: 37627290 PMCID: PMC10452872 DOI: 10.3390/biom13081225] [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: 06/15/2023] [Revised: 07/27/2023] [Accepted: 08/01/2023] [Indexed: 08/27/2023] Open
Abstract
Mitochondrial network architecture plays a critical role in cellular physiology. Indeed, alterations in the shape of mitochondria upon exposure to cellular stress can cause the dysfunction of these organelles. In this scenario, mitochondrial dynamics proteins and the phospholipid composition of the mitochondrial membrane are key for fine-tuning the modulation of mitochondrial architecture. In addition, several factors including post-translational modifications such as the phosphorylation, acetylation, SUMOylation, and o-GlcNAcylation of mitochondrial dynamics proteins contribute to shaping the plasticity of this architecture. In this regard, several studies have evidenced that, upon metabolic stress, mitochondrial dynamics proteins are post-translationally modified, leading to the alteration of mitochondrial architecture. Interestingly, several proteins that sustain the mitochondrial lipid composition also modulate mitochondrial morphology and organelle communication. In this context, pharmacological studies have revealed that the modulation of mitochondrial shape and function emerges as a potential therapeutic strategy for metabolic diseases. Here, we review the factors that modulate mitochondrial architecture.
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Affiliation(s)
- Juan Pablo Muñoz
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain
- Institut d’Investigació Biomèdica Sant Pau (IIB SANT PAU), 08041 Barcelona, Spain
| | - Fernanda Luisa Basei
- Faculdade de Ciências Farmacêuticas, Universidade Estadual de Campinas, 13083-871 Campinas, SP, Brazil
| | - María Laura Rojas
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba X5000HUA, Argentina
| | - David Galvis
- Programa de Química Farmacéutica, Universidad CES, Medellín 050031, Colombia
| | - Antonio Zorzano
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain
- Institute for Research in Biomedicine (IRB Barcelona), 08028 Barcelona, Spain
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain
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7
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Okamoto Y, Takashima H. The Current State of Charcot-Marie-Tooth Disease Treatment. Genes (Basel) 2023; 14:1391. [PMID: 37510296 PMCID: PMC10379063 DOI: 10.3390/genes14071391] [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: 05/28/2023] [Revised: 06/20/2023] [Accepted: 06/29/2023] [Indexed: 07/30/2023] Open
Abstract
Charcot-Marie-Tooth disease (CMT) and associated neuropathies are the most predominant genetically transmitted neuromuscular conditions; however, effective pharmacological treatments have not established. The extensive genetic heterogeneity of CMT, which impacts the peripheral nerves and causes lifelong disability, presents a significant barrier to the development of comprehensive treatments. An estimated 100 loci within the human genome are linked to various forms of CMT and its related inherited neuropathies. This review delves into prospective therapeutic strategies used for the most frequently encountered CMT variants, namely CMT1A, CMT1B, CMTX1, and CMT2A. Compounds such as PXT3003, which are being clinically and preclinically investigated, and a broad array of therapeutic agents and their corresponding mechanisms are discussed. Furthermore, the progress in established gene therapy techniques, including gene replacement via viral vectors, exon skipping using antisense oligonucleotides, splicing modification, and gene knockdown, are appraised. Each of these gene therapies has the potential for substantial advancements in future research.
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Affiliation(s)
- Yuji Okamoto
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan
- Department of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, Kagoshima 890-8544, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan
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8
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Dorn GW. Reversing Dysdynamism to Interrupt Mitochondrial Degeneration in Amyotrophic Lateral Sclerosis. Cells 2023; 12:1188. [PMID: 37190097 PMCID: PMC10136928 DOI: 10.3390/cells12081188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/13/2023] [Accepted: 04/14/2023] [Indexed: 05/17/2023] Open
Abstract
Amyotrophic lateral sclerosis is one of several chronic neurodegenerative conditions in which mitochondrial abnormalities are posited to contribute to disease progression. Therapeutic options targeting mitochondria include enhancing metabolism, suppressing reactive oxygen production and disrupting mitochondria-mediated programmed cell death pathways. Herein is reviewed mechanistic evidence supporting a meaningful pathophysiological role for the constellation of abnormal mitochondrial fusion, fission and transport, collectively designated mitochondrial dysdynamism, in ALS. Following this is a discussion on preclinical studies in ALS mice that seemingly validate the idea that normalizing mitochondrial dynamism can delay ALS by interrupting a vicious cycle of mitochondrial degeneration, leading to neuronal die-back and death. Finally, the relative benefits of suppressing mitochondrial fusion vs. enhancing mitochondrial fusion in ALS are speculated upon, and the paper concludes with the prediction that the two approaches could be additive or synergistic, although a side-by-side comparative trial may be challenging to perform.
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Affiliation(s)
- Gerald W Dorn
- Department of Internal Medicine (Pharmacogenomics), Washington University School of Medicine, St. Louis, MO 63110, USA
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9
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Dang X, Zhang L, Franco A, Dorn II GW. Activating mitofusins interrupts mitochondrial degeneration and delays disease progression in SOD1 mutant amyotrophic lateral sclerosis. Hum Mol Genet 2023; 32:1208-1222. [PMID: 36416308 PMCID: PMC10026224 DOI: 10.1093/hmg/ddac287] [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: 09/06/2022] [Revised: 10/25/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022] Open
Abstract
Mitochondrial involvement in neurodegenerative diseases is widespread and multifactorial. Targeting mitochondrial pathology is therefore of interest. The recent development of bioactive molecules that modulate mitochondrial dynamics (fusion, fission and motility) offers a new therapeutic approach for neurodegenerative diseases with either indirect or direct mitochondrial involvement. Here, we asked: (1) Can enhanced mitochondrial fusion and motility improve secondary mitochondrial pathology in superoxide dismutase1 (SOD1) mutant amyotrophic lateral sclerosis (ALS)? And: (2) What is the impact of enhancing mitochondria fitness on in vivo manifestations of SOD1 mutant ALS? We observed that small molecule mitofusin activators corrected mitochondrial fragmentation, depolarization and dysmotility in genetically diverse ALS patient reprogrammed motor neurons and fibroblasts, and in motor neurons, sensory neurons and fibroblasts from SOD1 G93A mice. Continuous, but not intermittent, pharmacologic mitofusin activation delayed phenotype progression and lethality in SOD1 G93A mice, reducing neuron loss and improving neuromuscular connectivity. Mechanistically, mitofusin activation increased mitochondrial motility, fitness and residency within neuromuscular synapses; reduced mitochondrial reactive oxygen species production; and diminished apoptosis in SOD1 mutant neurons. These benefits were accompanied by improved mitochondrial respiratory coupling, despite characteristic SOD1 mutant ALS-associated downregulation of mitochondrial respiratory complexes. Targeting mitochondrial dysdynamism is a promising approach to alleviate pathology caused by secondary mitochondrial dysfunction in some neurodegenerative diseases.
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Affiliation(s)
- Xiawei Dang
- Department of Internal Medicine, Washington University School of Medicine, St. Louis MO USA
- Department of Psychiatry, The First Affiliated Hospital of Xi’an Jiao Tong University, Xi’an, Shaanxi 710061, China
| | - Lihong Zhang
- Department of Internal Medicine, Washington University School of Medicine, St. Louis MO USA
| | - Antonietta Franco
- Department of Internal Medicine, Washington University School of Medicine, St. Louis MO USA
| | - Gerald W Dorn II
- Department of Internal Medicine, Washington University School of Medicine, St. Louis MO USA
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10
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Franco A, Walton CE, Dang X. Mitochondria Clumping vs. Mitochondria Fusion in CMT2A Diseases. LIFE (BASEL, SWITZERLAND) 2022; 12:life12122110. [PMID: 36556475 PMCID: PMC9783122 DOI: 10.3390/life12122110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/08/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022]
Abstract
Phenotypic variations in Charcot-Marie-Tooth disease type 2A (CMT2A) result from the many mutations in the mitochondrial fusion protein, mitofusin 2 (MFN2). While the GTPase domain mutations of MFN2 lack the ability to hydrolyze GTP and complete mitochondrial fusion, the mechanism of dysfunction in HR1 domain mutations has yet to be explored. Using Mfn1/Mfn2 double null cells and Mfn2 knock out (KO) fibroblasts, we measured the ability of this variant protein to change conformations and hydrolyze GTP. We found that a mutation in the HR1 domain (M376A) of MFN2 results in conformational change dysfunction while maintaining GTPase ability. Prolonged exposure to mitofusin agonist MiM 111 reverses mitochondrial fusion dysfunction in the HR1 mutant through encouraging an open conformation, resulting in a potential therapeutic model in this variant. Herein, we describe a novel mechanism of dysfunction in MFN2 variants through exploring domain-specific mitochondrial characteristics leading to CMT2A.
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Affiliation(s)
- Antonietta Franco
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
- Correspondence: ; Tel.: +1-314-362-4892; Fax: +1-314-362-8844
| | - Caroline E. Walton
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
- University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Xiawei Dang
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
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11
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Franco A, Dang X, Zhang L, Molinoff PB, Dorn GW. Mitochondrial Dysfunction and Pharmacodynamics of Mitofusin Activation in Murine Charcot-Marie-Tooth Disease Type 2A. J Pharmacol Exp Ther 2022; 383:137-148. [PMID: 36507849 PMCID: PMC9553116 DOI: 10.1124/jpet.122.001332] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 08/03/2022] [Indexed: 01/07/2023] Open
Abstract
Mitofusin (MFN) 1 and MFN2 are dynamin GTPase family mitochondrial proteins that mediate mitochondrial fusion requiring MFN conformational shifts, formation of macromolecular complexes on and between mitochondria, and GTP hydrolysis. Damaging MFN2 mutations cause an untreatable, largely pediatric progressive peripheral neuropathy, Charcot-Marie-Tooth (CMT) disease type 2A. We used small molecule allosteric mitofusin activators that promote MFN conformations favoring fusion to interrogate the effects of MFN2 conformation and GTPase activity on MFN2-mediated mitochondrial fusion and motility in vitro. We translated these findings in vivo by defining dose-dependent pharmacodynamic and disease-modifying effects of mitofusin activators in murine CMT2A. MFN2 catalytic GTPase activity and MFN2 conformational switching are essential for mitochondrial fusion, but the two processes are separate and dissociable. We report the first concentration-response relationships for mitofusin activators to stimulate mitochondrial transport through CMT2A neuronal axons, which is similar to their stimulation of mitochondrial fusion. In CMT2A mice, intermittent (daily short acting) and sustained (twice daily long acting) mitofusin activation were equally effective in reversing neuromuscular degeneration. Moreover, acute dose-dependent pharmacodynamic effects of mitofusin activators on mitochondrial transport through CMT2A neuronal axons anticipated those for long-term reversal of neurodegenerative phenotypes. A crossover study showed that CMT2A neuronal deficits recurred after mitofusin activators are discontinued, and revealed that CMT2A can be ameliorated by mitofusin activation even in old (>74 week) mice. These data add to our understanding of mitochondrial dysfunction induced by a CMT2A MFN2 GTPase mutation and provide additional information supporting the approach of pharmacological mitofusin activation in CMT2A. SIGNIFICANCE: This study interrogated the roles of MFN2 catalytic activity and allosteric activation on impaired mitochondrial fusion and neuronal transport as they impact an untreatable peripheral neuropathy caused by MFN2 mutations, Charcot-Marie-Tooth disease type 2A. The results mechanistically link mitochondrial fusion and motility to the relaxed MFN2 protein conformation and correction of mitochondrial abnormalities to in vivo reversal of neurodegeneration in murine CMT2A.
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Affiliation(s)
- Antonietta Franco
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri (A.F., X.D., L.Z., G.W.D.); Department of Cardiology, The First Affiliated Hospital of Xi'an Jiao Tong University, Xi'an, Shaanxi, China (X.D.); Mitochondria in Motion Inc., St. Louis, Missouri (L.Z.); and Department of Pharmacology, University of Pennsylvania, Philadelphia, Pennsylvania (P.B.M.)
| | - Xiawei Dang
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri (A.F., X.D., L.Z., G.W.D.); Department of Cardiology, The First Affiliated Hospital of Xi'an Jiao Tong University, Xi'an, Shaanxi, China (X.D.); Mitochondria in Motion Inc., St. Louis, Missouri (L.Z.); and Department of Pharmacology, University of Pennsylvania, Philadelphia, Pennsylvania (P.B.M.)
| | - Lihong Zhang
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri (A.F., X.D., L.Z., G.W.D.); Department of Cardiology, The First Affiliated Hospital of Xi'an Jiao Tong University, Xi'an, Shaanxi, China (X.D.); Mitochondria in Motion Inc., St. Louis, Missouri (L.Z.); and Department of Pharmacology, University of Pennsylvania, Philadelphia, Pennsylvania (P.B.M.)
| | - Perry B Molinoff
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri (A.F., X.D., L.Z., G.W.D.); Department of Cardiology, The First Affiliated Hospital of Xi'an Jiao Tong University, Xi'an, Shaanxi, China (X.D.); Mitochondria in Motion Inc., St. Louis, Missouri (L.Z.); and Department of Pharmacology, University of Pennsylvania, Philadelphia, Pennsylvania (P.B.M.)
| | - Gerald W Dorn
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri (A.F., X.D., L.Z., G.W.D.); Department of Cardiology, The First Affiliated Hospital of Xi'an Jiao Tong University, Xi'an, Shaanxi, China (X.D.); Mitochondria in Motion Inc., St. Louis, Missouri (L.Z.); and Department of Pharmacology, University of Pennsylvania, Philadelphia, Pennsylvania (P.B.M.)
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12
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Almannai M, El-Hattab AW, Azamian MS, Ali M, Scaglia F. Mitochondrial DNA maintenance defects: potential therapeutic strategies. Mol Genet Metab 2022; 137:40-48. [PMID: 35914366 PMCID: PMC10401187 DOI: 10.1016/j.ymgme.2022.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 07/03/2022] [Accepted: 07/03/2022] [Indexed: 10/17/2022]
Abstract
Mitochondrial DNA (mtDNA) replication depends on the mitochondrial import of hundreds of nuclear encoded proteins that control the mitochondrial genome maintenance and integrity. Defects in these processes result in an expanding group of disorders called mtDNA maintenance defects that are characterized by mtDNA depletion and/or multiple mtDNA deletions with variable phenotypic manifestations. As it applies for mitochondrial disorders in general, current treatment options for mtDNA maintenance defects are limited. Lately, with the development of model organisms, improved understanding of the pathophysiology of these disorders, and a better knowledge of their natural history, the number of preclinical studies and existing and planned clinical trials has been increasing. In this review, we discuss recent preclinical studies and current and future clinical trials concerning potential therapeutic options for the different mtDNA maintenance defects.
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Affiliation(s)
- Mohammed Almannai
- Genetics and Precision Medicine Department (GPM), King Abdullah Specialized Children's Hospital (KASCH), King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG-HA), Riyadh, Saudi Arabia
| | - Ayman W El-Hattab
- Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
| | - Mahshid S Azamian
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - May Ali
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Texas Children's Hospital, Houston, TX, USA; Joint BCM-CUHK Center of Medical Genetics, Prince of Wales Hospital, Shatin, Hong Kong.
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13
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Dorn Ii GW. Neurohormonal Connections with Mitochondria in Cardiomyopathy and Other Diseases. Am J Physiol Cell Physiol 2022; 323:C461-C477. [PMID: 35759434 PMCID: PMC9363002 DOI: 10.1152/ajpcell.00167.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Neurohormonal signaling and mitochondrial dynamism are seemingly distinct processes that are almost ubiquitous among multicellular organisms. Both of these processes are regulated by GTPases, and disturbances in either can provoke disease. Here, inconspicuous pathophysiological connectivity between neurohormonal signaling and mitochondrial dynamism is reviewed in the context of cardiac and neurological syndromes. For both processes, greater understanding of basic mechanisms has evoked a reversal of conventional pathophysiological concepts. Thus, neurohormonal systems induced in, and previously thought to be critical for, cardiac functioning in heart failure are now pharmaceutically interrupted as modern standard of care. And, mitochondrial abnormalities in neuropathies that were originally attributed to an imbalance between mitochondrial fusion and fission are increasingly recognized as an interruption of axonal mitochondrial transport. The data are presented in a historical context to provided insight into how scientific thought has evolved and to foster an appreciation for how seemingly different areas of investigation can converge. Finally, some theoretical notions are presented to explain how different molecular and functional defects can evoke tissue-specific disease.
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Affiliation(s)
- Gerald W Dorn Ii
- Center for Pharmacogenomics, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, United States
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14
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Piperine Derivatives Enhance Fusion and Axonal Transport of Mitochondria by Activating Mitofusins. CHEMISTRY 2022. [DOI: 10.3390/chemistry4030047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Piperine (1-piperoylpiperidine) is the major pungent component of black pepper (Piper nigrum) and exhibits a spectrum of pharmacological activities. The molecular bases for many of piperine’s biological effects are incompletely defined. We noted that the chemical structure of piperine generally conforms to a pharmacophore model for small bioactive molecules that activate mitofusin (MFN)-mediated mitochondrial fusion. Piperine, but not its isomer chavicine, stimulated mitochondrial fusion in MFN-deficient cells with EC50 of ~8 nM. We synthesized piperine analogs having structural features predicted to optimize mitofusin activation and defined structure-activity relationships (SAR) in live-cell mitochondrial elongation assays. When optimal spacing was maintained between amide and aromatic groups the derivatives were potent mitofusin activators. Compared to the prototype phenylhexanamide mitofusin activator, 2, novel molecules containing the piperidine structure of piperine exhibited markedly enhanced passive membrane permeability with no loss of fusogenic potency. Lead compounds 5 and 8 enhanced mitochondrial motility in cultured murine Charcot-Marie-Tooth disease type 2A (CMT2A) neurons, but only 8 improved mitochondrial transport in sciatic nerve axons of CMT2A mice. Piperine analogs represent a new chemical class of mitofusin activators with potential pharmaceutical advantages.
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15
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Almannai M, Salah A, El-Hattab AW. Mitochondrial Membranes and Mitochondrial Genome: Interactions and Clinical Syndromes. MEMBRANES 2022; 12:membranes12060625. [PMID: 35736332 PMCID: PMC9229594 DOI: 10.3390/membranes12060625] [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] [Received: 05/09/2022] [Revised: 06/06/2022] [Accepted: 06/14/2022] [Indexed: 11/16/2022]
Abstract
Mitochondria are surrounded by two membranes; the outer mitochondrial membrane and the inner mitochondrial membrane. They are unique organelles since they have their own DNA, the mitochondrial DNA (mtDNA), which is replicated continuously. Mitochondrial membranes have direct interaction with mtDNA and are therefore involved in organization of the mitochondrial genome. They also play essential roles in mitochondrial dynamics and the supply of nucleotides for mtDNA synthesis. In this review, we will discuss how the mitochondrial membranes interact with mtDNA and how this interaction is essential for mtDNA maintenance. We will review different mtDNA maintenance disorders that result from defects in this crucial interaction. Finally, we will review therapeutic approaches relevant to defects in mitochondrial membranes.
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Affiliation(s)
- Mohammed Almannai
- Genetics and Precision Medicine Department, King Abdullah Specialized Children Hospital, Riyadh P.O. Box 22490, Saudi Arabia
- Correspondence:
| | - Azza Salah
- Department of Pediatrics, University Hospital Sharjah, Sharjah P.O. Box 72772, United Arab Emirates;
| | - Ayman W. El-Hattab
- Department of Pediatrics, University Hospital Sharjah, Sharjah P.O. Box 72772, United Arab Emirates;
- Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah P.O. Box 27272, United Arab Emirates;
- Genetics and Metabolic Department, KidsHeart Medical Center, Abu Dhabi P.O. Box 505193, United Arab Emirates
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16
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Christoffersen BØ, Sanchez‐Delgado G, John LM, Ryan DH, Raun K, Ravussin E. Beyond appetite regulation: Targeting energy expenditure, fat oxidation, and lean mass preservation for sustainable weight loss. Obesity (Silver Spring) 2022; 30:841-857. [PMID: 35333444 PMCID: PMC9310705 DOI: 10.1002/oby.23374] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 11/09/2021] [Accepted: 12/10/2021] [Indexed: 12/17/2022]
Abstract
New appetite-regulating antiobesity treatments such as semaglutide and agents under investigation such as tirzepatide show promise in achieving weight loss of 15% or more. Energy expenditure, fat oxidation, and lean mass preservation are important determinants of weight loss and weight-loss maintenance beyond appetite regulation. This review discusses prior failures in clinical development of weight-loss drugs targeting energy expenditure and explores novel strategies for targeting energy expenditure: mitochondrial proton leak, uncoupling, dynamics, and biogenesis; futile calcium and substrate cycling; leptin for weight maintenance; increased sympathetic nervous system activity; and browning of white fat. Relevant targets for preserving lean mass are also reviewed: growth hormone, activin type II receptor inhibition, and urocortin 2 and 3. We endorse moderate modulation of energy expenditure and preservation of lean mass in combination with efficient appetite reduction as a means of obtaining a significant, safe, and long-lasting weight loss. Furthermore, we suggest that the regulatory guidelines should be revisited to focus more on the quality of weight loss and its maintenance rather than the absolute weight loss. Commitment to this research focus both from a scientific and from a regulatory point of view could signal the beginning of the next era in obesity therapies.
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Affiliation(s)
| | | | - Linu Mary John
- Global Obesity and Liver Disease ResearchGlobal Drug DiscoveryNovo Nordisk A/SMåløvDenmark
| | - Donna H. Ryan
- Pennington Biomedical Research CenterLouisiana State UniversityBaton RougeLouisianaUSA
| | - Kirsten Raun
- Global Obesity and Liver Disease ResearchGlobal Drug DiscoveryNovo Nordisk A/SMåløvDenmark
| | - Eric Ravussin
- Pennington Biomedical Research CenterLouisiana State UniversityBaton RougeLouisianaUSA
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17
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Dang X, Walton EK, Zablocka B, Baloh RH, Shy ME, Dorn GW. Mitochondrial Phenotypes in Genetically Diverse Neurodegenerative Diseases and Their Response to Mitofusin Activation. Cells 2022; 11:cells11061053. [PMID: 35326504 PMCID: PMC8947610 DOI: 10.3390/cells11061053] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/08/2022] [Accepted: 03/16/2022] [Indexed: 01/27/2023] Open
Abstract
Mitochondrial fusion is essential to mitochondrial fitness and cellular health. Neurons of patients with genetic neurodegenerative diseases often exhibit mitochondrial fragmentation, reflecting an imbalance in mitochondrial fusion and fission (mitochondrial dysdynamism). Charcot–Marie–Tooth (CMT) disease type 2A is the prototypical disorder of impaired mitochondrial fusion caused by mutations in the fusion protein mitofusin (MFN)2. Yet, cultured CMT2A patient fibroblast mitochondria are often reported as morphologically normal. Metabolic stress might evoke pathological mitochondrial phenotypes in cultured patient fibroblasts, providing a platform for the pre-clinical individualized evaluation of investigational therapeutics. Here, substitution of galactose for glucose in culture media was used to redirect CMT2A patient fibroblasts (MFN2 T105M, R274W, H361Y, R364W) from glycolytic metabolism to mitochondrial oxidative phosphorylation, which provoked characteristic mitochondrial fragmentation and depolarization and induced a distinct transcriptional signature. Pharmacological MFN activation of metabolically reprogrammed fibroblasts partially reversed the mitochondrial abnormalities in CMT2A and CMT1 and a subset of Parkinson’s and Alzheimer’s disease patients, implicating addressable mitochondrial dysdynamism in these illnesses.
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Affiliation(s)
- Xiawei Dang
- Center for Pharmacogenomics, Department of Internal Medicine, Washington University School of Medicine, 660 S. Euclid Ave, St. Louis, MO 63110, USA; (X.D.); (E.K.W.)
| | - Emily K. Walton
- Center for Pharmacogenomics, Department of Internal Medicine, Washington University School of Medicine, 660 S. Euclid Ave, St. Louis, MO 63110, USA; (X.D.); (E.K.W.)
| | - Barbara Zablocka
- Mossakowski Medical Research Institute, Polish Academy of Sciences, 02-106 Warsaw, Poland;
| | - Robert H. Baloh
- Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA;
| | - Michael E. Shy
- Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA;
| | - Gerald W. Dorn
- Center for Pharmacogenomics, Department of Internal Medicine, Washington University School of Medicine, 660 S. Euclid Ave, St. Louis, MO 63110, USA; (X.D.); (E.K.W.)
- Correspondence: ; Tel.: +1-314-362-4892
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18
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Gao Z, Zhang R, Jiang L, Zhou H, Wang Q, Ma Y, Zhang D, Qin Y, Tian P, Zhang N, Shi Z, Xu S. Administration of miR-195 Inhibitor Enhances Memory Function Through Improving Synaptic Degradation and Mitochondrial Dysfunction of the Hippocampal Neurons in SAMP8 Mice. J Alzheimers Dis 2021; 85:1495-1509. [PMID: 34924391 DOI: 10.3233/jad-215301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Mitochondrial dysfunction is an early feature of Alzheimer's disease (AD) and miR-195 is involved in mitochondrial disorder through targeting MFN-2 protein in hippocampal neurons of AD. OBJECTIVE To clarify if administration of miR-195 inhibitor could enhance the memory deficits through improving hippocampal neuron mitochondrial dysfunction in SAMP8 mice. METHODS The expression of miR-195 was detected by RT-qPCR in primary hippocampal neurons and HT-22 cells treated with Aβ 1-42. Morris water maze (MWM) was used to assess the learning and memory function in SAMP8 mice administrated with antagomir-195. Transmission electron microscopy was employed to determine the morphological changes of synapses and mitochondria of hippocampus in SAMP8 mice. Mitochondrial respiration was measured using a high-resolution oxygraph. RESULTS The expression of miR-195 were upregulated in the primary hippocampal neurons and HT-22 cells induced by Aβ 1-42. Inhibition of miR-195 ameliorated the mitochondrial dysfunction in HT-22 cells induced by Aβ 1-42, including mitochondrial morphologic damages, mitochondrial membrane potential, respiration function, and ATP production. Administration of antagomir-195 by the third ventricle injection markedly ameliorated the cognitive function, postsynaptic density thickness, length of synaptic active area, mitochondrial aspect ratio, and area in hippocampus of SAMP8 mice. Finally, antagomir-195 was able to promote an increase in the activity of respiratory chain complex CI and II in SAMP8 mice. CONCLUSION This study demonstrated that miR-195 inhibitor ameliorated the cognitive impairment of AD mice by improving mitochondrial structure damages and dysfunction in the hippocampal neurons, which provide an experimental basis for further exploring the treatment strategy of AD.
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Affiliation(s)
- Zhaoyu Gao
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China
| | - Rui Zhang
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China
| | - Lei Jiang
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China
| | - Huimin Zhou
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China.,Department of Endocrinology, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China
| | - Qian Wang
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China
| | - Yingxin Ma
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China
| | - Di Zhang
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China
| | - Yushi Qin
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China
| | - Pei Tian
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China
| | - Nan Zhang
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China
| | - Zhongli Shi
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China
| | - Shunjiang Xu
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China.,Hebei International Joint Research Center for Brain Science, Shijiazhuang, P. R. China.,Hebei Key Laboratory of Brain Science and Psychiatric-Psychologic Disease, Shijiazhuang, P. R. China
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19
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Zhang T, Li J, Zhao G. Quality Control Mechanisms of Mitochondria: Another Important Target for Treatment of Peripheral Neuropathy. DNA Cell Biol 2021; 40:1513-1527. [PMID: 34851723 DOI: 10.1089/dna.2021.0529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mitochondria provide energy for various cellular activities and are involved in the regulating of several physiological and pathological processes. Mitochondria constitute a dynamic network regulated by numerous quality control mechanisms; for example, division is necessary for mitochondria to develop, and fusion dilutes toxins produced by the mitochondria. Mitophagy removes damaged mitochondria. The etiologies of peripheral neuropathy include congenital and acquired diseases, and the pathogenesis varies; however, oxidative stress caused by mitochondrial damage is the accepted pathogenesis of peripheral neuropathy. Regulation and control of mitochondrial quality might point the way toward potential treatments for peripheral neuropathy. This article will review mitochondrial quality control mechanisms, their involvement in peripheral nerve diseases, and their potential therapeutic role.
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Affiliation(s)
- Te Zhang
- China-Japan Union Hospital of Jilin University, Changchun, P.R. China
| | - Jiannan Li
- China-Japan Union Hospital of Jilin University, Changchun, P.R. China
| | - Guoqing Zhao
- China-Japan Union Hospital of Jilin University, Changchun, P.R. China
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20
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Dorn GW. Mitofusin activation enhances mitochondrial motility and promotes neuroregeneration in CMT2A. Neural Regen Res 2021; 16:2201-2203. [PMID: 33818493 PMCID: PMC8354110 DOI: 10.4103/1673-5374.310684] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 12/24/2020] [Accepted: 01/30/2021] [Indexed: 11/04/2022] Open
Affiliation(s)
- Gerald W. Dorn
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, USA
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21
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Yang K, Hu HY, Zhang J, Yan YS, Chen WQ, Liu Y, Sun YQ, Guo Q, Yin CH. Metabolic and biophysical study of the MFN2 Ile213Thr mutant causing Hereditary Motor and Sensory Neuropathy (HMSN). Am J Transl Res 2021; 13:11501-11512. [PMID: 34786076 PMCID: PMC8581889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
Charcot-Marie-Tooth (CMT) 2A disease, a genetic axonal nervous lesion, results from MFN2 pathogenic variation, and this gene plays a pivotal role in mitochondrial dynamics and calcium signaling. However, the underlying mechanism linking MFN2 defect to progressive dying-back of peripheral nerves is still unclear. The present work focused on analyzing one CMT2A patient from multiple perspectives. Clinical and pathologic evaluation was initially conducted on the recruited case. Subsequently, Sanger sequencing and whole-exome sequencing (WES) were performed for genetic detection. To reveal the cell metabolic alteration caused by the identified variant, this study also established and transfected plasmid vectors in HEK293 cells and analyzed cell metabolites through liquid chromatography in combination with quadrupole time-of-flight tandem mass spectrometry (UPLC Q-TOF MS). Additionally, we completed structural modeling and molecular dynamic (MD) simulation to investigate the intramolecular impact of the variant. According to our results, the clinical and neuropathologic manifestations of the proband matched with the diagnosis of CMT. The causative variant MFN2: c.638T>C: (p.Ile213Thr) was identified through genetic analysis. Moreover, metabolic pathway enrichment results demonstrated that this variant significantly affected the metabolism of sphingolipids and glycerophospholipids. MD analysis indicated that this variant crippled the binding ability of MFN2 to GTP. Taken together, our study deduced preliminary clues for the underlying mechanism by which mutant MFN2 affects cell metabolism and provided a novel perspective to understand the cellular and molecular impacts of MFN2 variants.
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Affiliation(s)
- Kai Yang
- Prenatal Diagnosis Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical UniversityBeijing, China
| | - Hua-Ying Hu
- Jiaen Genetics Laboratory, Beijing Jiaen HospitalBeijing 100191, China
| | - Jing Zhang
- Prenatal Diagnosis Center,Shijiazhuang Obstetrics and Gynecology HospitalShijiazhuang, Hebei, China
| | - You-Sheng Yan
- Prenatal Diagnosis Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical UniversityBeijing, China
| | - Wen-Qi Chen
- Prenatal Diagnosis Center,Shijiazhuang Obstetrics and Gynecology HospitalShijiazhuang, Hebei, China
| | - Yan Liu
- Prenatal Diagnosis Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical UniversityBeijing, China
| | - Yong-Qing Sun
- Prenatal Diagnosis Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical UniversityBeijing, China
| | - Qing Guo
- Prenatal Diagnosis Center,Shijiazhuang Obstetrics and Gynecology HospitalShijiazhuang, Hebei, China
| | - Cheng-Hong Yin
- Prenatal Diagnosis Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical UniversityBeijing, China
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22
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Sharif NA. Therapeutic Drugs and Devices for Tackling Ocular Hypertension and Glaucoma, and Need for Neuroprotection and Cytoprotective Therapies. Front Pharmacol 2021; 12:729249. [PMID: 34603044 PMCID: PMC8484316 DOI: 10.3389/fphar.2021.729249] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 08/18/2021] [Indexed: 12/11/2022] Open
Abstract
Damage to the optic nerve and the death of associated retinal ganglion cells (RGCs) by elevated intraocular pressure (IOP), also known as glaucoma, is responsible for visual impairment and blindness in millions of people worldwide. The ocular hypertension (OHT) and the deleterious mechanical forces it exerts at the back of the eye, at the level of the optic nerve head/optic disc and lamina cribosa, is the only modifiable risk factor associated with glaucoma that can be treated. The elevated IOP occurs due to the inability of accumulated aqueous humor (AQH) to egress from the anterior chamber of the eye due to occlusion of the major outflow pathway, the trabecular meshwork (TM) and Schlemm’s canal (SC). Several different classes of pharmaceutical agents, surgical techniques and implantable devices have been developed to lower and control IOP. First-line drugs to promote AQH outflow via the uveoscleral outflow pathway include FP-receptor prostaglandin (PG) agonists (e.g., latanoprost, travoprost and tafluprost) and a novel non-PG EP2-receptor agonist (omidenepag isopropyl, Eybelis®). TM/SC outflow enhancing drugs are also effective ocular hypotensive agents (e.g., rho kinase inhibitors like ripasudil and netarsudil; and latanoprostene bunod, a conjugate of a nitric oxide donor and latanoprost). One of the most effective anterior chamber AQH microshunt devices is the Preserflo® microshunt which can lower IOP down to 10–13 mmHg. Other IOP-lowering drugs and devices on the horizon will be also discussed. Additionally, since elevated IOP is only one of many risk factors for development of glaucomatous optic neuropathy, a treatise of the role of inflammatory neurodegeneration of the optic nerve and retinal ganglion cells and appropriate neuroprotective strategies to mitigate this disease will also be reviewed and discussed.
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Affiliation(s)
- Najam A Sharif
- Global Alliances and External Research, Ophthalmology Innovation Center, Santen Inc., Emeryville, CA, United States
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23
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McCray BA, Scherer SS. Axonal Charcot-Marie-Tooth Disease: from Common Pathogenic Mechanisms to Emerging Treatment Opportunities. Neurotherapeutics 2021; 18:2269-2285. [PMID: 34606075 PMCID: PMC8804038 DOI: 10.1007/s13311-021-01099-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2021] [Indexed: 01/12/2023] Open
Abstract
Inherited peripheral neuropathies are a genetically and phenotypically diverse group of disorders that lead to degeneration of peripheral neurons with resulting sensory and motor dysfunction. Genetic neuropathies that primarily cause axonal degeneration, as opposed to demyelination, are most often classified as Charcot-Marie-Tooth disease type 2 (CMT2) and are the focus of this review. Gene identification efforts over the past three decades have dramatically expanded the genetic landscape of CMT and revealed several common pathological mechanisms among various forms of the disease. In some cases, identification of the precise genetic defect and/or the downstream pathological consequences of disease mutations have yielded promising therapeutic opportunities. In this review, we discuss evidence for pathogenic overlap among multiple forms of inherited neuropathy, highlighting genetic defects in axonal transport, mitochondrial dynamics, organelle-organelle contacts, and local axonal protein translation as recurrent pathological processes in inherited axonal neuropathies. We also discuss how these insights have informed emerging treatment strategies, including specific approaches for single forms of neuropathy, as well as more general approaches that have the potential to treat multiple types of neuropathy. Such therapeutic opportunities, made possible by improved understanding of molecular and cellular pathogenesis and advances in gene therapy technologies, herald a new and exciting phase in inherited peripheral neuropathy.
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Affiliation(s)
- Brett A. McCray
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205 USA
| | - Steven S. Scherer
- Department of Neurology, The University of Pennsylvania, Philadelphia, PA 19104 USA
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24
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Dang X, Williams SB, Devanathan S, Franco A, Fu L, Bernstein PR, Walters D, Dorn GW. Pharmacophore-Based Design of Phenyl-[hydroxycyclohexyl] Cycloalkyl-Carboxamide Mitofusin Activators with Improved Neuronal Activity. J Med Chem 2021; 64:12506-12524. [PMID: 34415150 DOI: 10.1021/acs.jmedchem.1c00163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mitochondrial fragmentation from defective fusion or unopposed fission contributes to many neurodegenerative diseases. Small molecule mitofusin activators reverse mitochondrial fragmentation in vitro, promising a novel therapeutic approach. The first-in-class mitofusin activator, 2, has a short plasma t1/2 and limited neurological system bioavailability, conferring "burst activation". Here, pharmacophore-based rational redesign generated analogues of 2 incorporating cycloalkyl linker groups. A cyclopropyl-containing linker, 5, improved plasma and brain t1/2, increased nervous system bioavailability, and prolonged neuron pharmacodynamic effects. Functional and single-crystal X-ray diffraction studies of stereoisomeric analogues of 5 containing sulfur as a "heavy atom", 14A and 14B, showed that 5 biological activity resides in the trans-R/R configuration, 5B. Structural analysis revealed stereoselective interactions of 5 associated with its mimicry of MFN2 Val372, Met376, and His380 side chains. Modification of murine ALS phenotypes in vitro and in vivo supports advancement of 5B for neurological conditions that may benefit from sustained mitofusin activation.
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Affiliation(s)
- Xiawei Dang
- Department of Cardiology, The First Affiliated Hospital of Xi'an Jiao Tong University, Xi'an, Shaanxi 710061, China.,Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Sidney B Williams
- Mitochondria in Motion, Inc., 4340 Duncan Avenue, Suite 216, St. Louis, Missouri 63110, United States
| | - Sriram Devanathan
- Mitochondria in Motion, Inc., 4340 Duncan Avenue, Suite 216, St. Louis, Missouri 63110, United States
| | - Antonietta Franco
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Lijun Fu
- WuXi AppTec Co., Ltd., 666 Gaoxin Road, East Lake High-tech Development Zone, Wuhan, Hubei 430075, China
| | - Peter R Bernstein
- PharmaB LLC, 50 S. 16th Street, Unit 5201, Philadelphia, Pennsylvania 19102, United States
| | - Daniel Walters
- Crystal Pharmatech Inc., 3000 Eastpark Blvd., Ste 500B, Cranbury, New Jersey 08512, United States
| | - Gerald W Dorn
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States.,Mitochondria in Motion, Inc., 4340 Duncan Avenue, Suite 216, St. Louis, Missouri 63110, United States
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25
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Cervantes‐Silva MP, Cox SL, Curtis AM. Alterations in mitochondrial morphology as a key driver of immunity and host defence. EMBO Rep 2021; 22:e53086. [PMID: 34337844 PMCID: PMC8447557 DOI: 10.15252/embr.202153086] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/09/2021] [Accepted: 07/09/2021] [Indexed: 02/06/2023] Open
Abstract
Mitochondria are dynamic organelles whose architecture changes depending on the cell's energy requirements and other signalling events. These structural changes are collectively known as mitochondrial dynamics. Mitochondrial dynamics are crucial for cellular functions such as differentiation, energy production and cell death. Importantly, it has become clear in recent years that mitochondrial dynamics are a critical control point for immune cell function. Mitochondrial remodelling allows quiescent immune cells to rapidly change their metabolism and become activated, producing mediators, such as cytokines, chemokines and even metabolites to execute an effective immune response. The importance of mitochondrial dynamics in immunity is evident, as numerous pathogens have evolved mechanisms to manipulate host cell mitochondrial remodelling in order to promote their own survival. In this review, we comprehensively address the roles of mitochondrial dynamics in immune cell function, along with modulation of host cell mitochondrial morphology during viral and bacterial infections to facilitate either pathogen survival or host immunity. We also speculate on what the future may hold in terms of therapies targeting mitochondrial morphology for bacterial and viral control.
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Affiliation(s)
- Mariana P Cervantes‐Silva
- School of Pharmacy and Biomedical Sciences and Tissue Engineering Research GroupRoyal College of Surgeons in IrelandDublinIreland
| | - Shannon L Cox
- School of Pharmacy and Biomedical Sciences and Tissue Engineering Research GroupRoyal College of Surgeons in IrelandDublinIreland
| | - Annie M Curtis
- School of Pharmacy and Biomedical Sciences and Tissue Engineering Research GroupRoyal College of Surgeons in IrelandDublinIreland
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26
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Stavrou M, Sargiannidou I, Georgiou E, Kagiava A, Kleopa KA. Emerging Therapies for Charcot-Marie-Tooth Inherited Neuropathies. Int J Mol Sci 2021; 22:6048. [PMID: 34205075 PMCID: PMC8199910 DOI: 10.3390/ijms22116048] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/29/2021] [Accepted: 05/31/2021] [Indexed: 12/12/2022] Open
Abstract
Inherited neuropathies known as Charcot-Marie-Tooth (CMT) disease are genetically heterogeneous disorders affecting the peripheral nerves, causing significant and slowly progressive disability over the lifespan. The discovery of their diverse molecular genetic mechanisms over the past three decades has provided the basis for developing a wide range of therapeutics, leading to an exciting era of finding treatments for this, until now, incurable group of diseases. Many treatment approaches, including gene silencing and gene replacement therapies, as well as small molecule treatments are currently in preclinical testing while several have also reached clinical trial stage. Some of the treatment approaches are disease-specific targeted to the unique disease mechanism of each CMT form, while other therapeutics target common pathways shared by several or all CMT types. As promising treatments reach the stage of clinical translation, optimal outcome measures, novel biomarkers and appropriate trial designs are crucial in order to facilitate successful testing and validation of novel treatments for CMT patients.
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Affiliation(s)
- Marina Stavrou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Irene Sargiannidou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Elena Georgiou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Alexia Kagiava
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Kleopas A. Kleopa
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
- Center for Neuromuscular Diseases, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus
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27
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Chen L, Liu B, Qin Y, Li A, Gao M, Liu H, Gong G. Mitochondrial Fusion Protein Mfn2 and Its Role in Heart Failure. Front Mol Biosci 2021; 8:681237. [PMID: 34026850 PMCID: PMC8138128 DOI: 10.3389/fmolb.2021.681237] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 04/21/2021] [Indexed: 12/15/2022] Open
Abstract
Mitofusin 2 (Mfn2) is a transmembrane GTPase located on the mitochondrial outer membrane that contributes to mitochondrial network regulation. It is an essential multifunctional protein that participates in various biological processes under physical and pathological conditions, including mitochondrial fusion, reticulum–mitochondria contacts, mitochondrial quality control, and apoptosis. Mfn2 dysfunctions have been found to contribute to cardiovascular diseases, such as ischemia-reperfusion injury, heart failure, and dilated cardiomyopathy. Here, this review mainly focuses on what is known about the structure and function of Mfn2 and its crucial role in heart failure.
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Affiliation(s)
- Lei Chen
- Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Bilin Liu
- Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Yuan Qin
- Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China.,Department of Pharmacy, Shanghai East Hospital, Tongji University, Shanghai, China
| | - Anqi Li
- Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Meng Gao
- Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Hanyu Liu
- Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Guohua Gong
- Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China.,Department of Gastroenterology, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
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28
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Franco A, Dang X, Walton EK, Ho JN, Zablocka B, Ly C, Miller TM, Baloh RH, Shy ME, Yoo AS, Dorn GW. Burst mitofusin activation reverses neuromuscular dysfunction in murine CMT2A. eLife 2020; 9:61119. [PMID: 33074106 PMCID: PMC7655101 DOI: 10.7554/elife.61119] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 10/18/2020] [Indexed: 02/06/2023] Open
Abstract
Charcot–Marie-Tooth disease type 2A (CMT2A) is an untreatable childhood peripheral neuropathy caused by mutations of the mitochondrial fusion protein, mitofusin (MFN) 2. Here, pharmacological activation of endogenous normal mitofusins overcame dominant inhibitory effects of CMT2A mutants in reprogrammed human patient motor neurons, reversing hallmark mitochondrial stasis and fragmentation independent of causal MFN2 mutation. In mice expressing human MFN2 T105M, intermittent mitofusin activation with a small molecule, MiM111, normalized CMT2A neuromuscular dysfunction, reversed pre-treatment axon and skeletal myocyte atrophy, and enhanced axon regrowth by increasing mitochondrial transport within peripheral axons and promoting in vivo mitochondrial localization to neuromuscular junctional synapses. MiM111-treated MFN2 T105M mouse neurons exhibited accelerated primary outgrowth and greater post-axotomy regrowth, linked to enhanced mitochondrial motility. MiM111 is the first pre-clinical candidate for CMT2A. Charcot-Marie-Tooth disease type 2A is a rare genetic childhood disease where dying back of nerve cells leads to muscle loss in the arms and legs, causing permanent disability. There is no known treatment. In this form of CMT, mutations in a protein called mitofusin 2 damage structures inside cells known as mitochondria. Mitochondria generate most of the chemical energy to power a cell, but when mitofusin 2 is mutated, the mitochondria are less healthy and are unable to move within the cell, depriving the cells of energy. This particularly causes problems in the long nerve cells that stretch from the spinal cord to the arm and leg muscles. Now, Franco, Dang et al. wanted to see whether re-activating mitofusin 2 could correct the damage to the mitochondria and restore the nerve connections to the muscles. The researchers tested a new class of drug called a mitofusin activator on nerve cells grown in the laboratory after being taken from people suffering from CMT2A, and also from a mouse model of the disease. Mitofusin activators improved the structure, fitness and movement of mitochondria in both human and mice nerve cells. Franco, Dang et al. then tested the drug in the mice with a CMT2A mutation and found that it could also stimulate nerves to regrow and so reverse muscle loss and weakness. This is the first time scientists have succeeded to reverse the effects of CMT2A in nerve cells of mice and humans. However, these drugs will still need to go through extensive testing in clinical trials before being made widely available to patients. If approved, mitofusin activators may also be beneficial for patients suffering from other genetic conditions that damage mitochondria.
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Affiliation(s)
- Antonietta Franco
- Department of Internal Medicine, Pharmacogenomics, Washington University School of Medicine, St Louis, United States
| | - Xiawei Dang
- Department of Internal Medicine, Pharmacogenomics, Washington University School of Medicine, St Louis, United States.,Department of Cardiology, The First Affiliated Hospital of Xi'an Jiao Tong University, Xi'an, China
| | - Emily K Walton
- Department of Internal Medicine, Pharmacogenomics, Washington University School of Medicine, St Louis, United States
| | - Joshua N Ho
- Department of Developmental Biology, Washington University School of Medicine, St Louis, United States.,Center for Regenerative Medicine, Washington University School of Medicine, St. Louis, United States
| | - Barbara Zablocka
- Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Cindy Ly
- Department of Neurology, Washington University School of Medicine, St Louis, United States
| | - Timothy M Miller
- Department of Neurology, Washington University School of Medicine, St Louis, United States
| | - Robert H Baloh
- Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, United States
| | - Michael E Shy
- Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, United States
| | - Andrew S Yoo
- Department of Developmental Biology, Washington University School of Medicine, St Louis, United States.,Center for Regenerative Medicine, Washington University School of Medicine, St. Louis, United States
| | - Gerald W Dorn
- Department of Internal Medicine, Pharmacogenomics, Washington University School of Medicine, St Louis, United States
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