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Sala D, Marchet S, Nanetti L, Legati A, Mariotti C, Lamantea E, Ghezzi D, Catania A, Lamperti C. A novel MT-ATP6 variant associated with complicated ataxia in two unrelated Italian patients: case report and functional studies. Orphanet J Rare Dis 2024; 19:200. [PMID: 38755691 PMCID: PMC11100036 DOI: 10.1186/s13023-024-03212-y] [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: 03/10/2023] [Accepted: 05/09/2024] [Indexed: 05/18/2024] Open
Abstract
BACKGROUND MT-ATP6 is a mitochondrial gene which encodes for the intramembrane subunit 6 (or A) of the mitochondrial ATP synthase, also known asl complex V, which is involved in the last step of oxidative phosphorylation to produce cellular ATP through aerobic metabolism. Although classically associated with the NARP syndrome, recent evidence highlights an important role of MT-ATP6 pathogenic variants in complicated adult-onset ataxias. METHODS We describe two unrelated patients with adult-onset cerebellar ataxia associated with severe optic atrophy and mild cognitive impairment. Whole mitochondrial DNA sequencing was performed in both patients. We employed patients' primary fibroblasts and cytoplasmic hybrids (cybrids), generated from patients-derived cells, to assess the activity of respiratory chain complexes, oxygen consumption rate (OCR), ATP production and mitochondrial membrane potential. RESULTS In both patients, we identified the same novel m.8777 T > C variant in MT-ATP6 with variable heteroplasmy level in different tissues. We identifed an additional heteroplasmic novel variant in MT-ATP6, m.8879G > T, in the patients with the most severe phenotype. A significant reduction in complex V activity, OCR and ATP production was observed in cybrid clones homoplasmic for the m.8777 T > C variant, while no functional defect was detected in m.8879G > T homoplasmic clones. In addition, fibroblasts with high heteroplasmic levelsof m.8777 T > C variant showed hyperpolarization of mitochondrial membranes. CONCLUSIONS We describe a novel pathogenic mtDNA variant in MT-ATP6 associated with adult-onset ataxia, reinforcing the value of mtDNA screening within the diagnostic workflow of selected patients with late onset ataxias.
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Affiliation(s)
- Daniele Sala
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Silvia Marchet
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Lorenzo Nanetti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Andrea Legati
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Caterina Mariotti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Eleonora Lamantea
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Daniele Ghezzi
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
- Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122, Milan, Italy
| | - Alessia Catania
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Costanza Lamperti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy.
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2
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The Mitochondrial tRNA Ser(UCN) Gene: A Novel m.7484A>G Mutation Associated with Mitochondrial Encephalomyopathy and Literature Review. Life (Basel) 2023; 13:life13020554. [PMID: 36836911 PMCID: PMC9963529 DOI: 10.3390/life13020554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 01/26/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023] Open
Abstract
Mitochondrial tRNASer(UCN) is considered a hot-spot for non-syndromic and aminoglycoside-induced hearing loss. However, many patients have been described with more extensive neurological diseases, mainly including epilepsy, myoclonus, ataxia, and myopathy. We describe a novel homoplasmic m.7484A>G mutation in the tRNASer(UCN) gene affecting the third base of the anticodon triplet in a girl with profound intellectual disability, spastic tetraplegia, sensorineural hearing loss, a clinical history of epilepsia partialis continua and vomiting, typical of MELAS syndrome, leading to a myoclonic epilepticus status, and myopathy with severe COX deficiency at muscle biopsy. The mutation was also found in the homoplasmic condition in the mother who presented with mild cognitive deficit, cerebellar ataxia, myoclonic epilepsy, sensorineural hearing loss and myopathy with COX deficient ragged-red fibers consistent with MERRF syndrome. This is the first anticodon mutation in the tRNASer(UCN) and the second homoplasmic mutation in the anticodon triplet reported to date.
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3
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Bubb K, Holzer T, Nolte JL, Krüger M, Wilson R, Schlötzer-Schrehardt U, Brinckmann J, Altmüller J, Aszodi A, Fleischhauer L, Clausen-Schaumann H, Probst K, Brachvogel B. Mitochondrial respiratory chain function promotes extracellular matrix integrity in cartilage. J Biol Chem 2021; 297:101224. [PMID: 34560099 PMCID: PMC8503590 DOI: 10.1016/j.jbc.2021.101224] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 09/13/2021] [Accepted: 09/20/2021] [Indexed: 12/18/2022] Open
Abstract
Energy metabolism and extracellular matrix (ECM) function together orchestrate and maintain tissue organization, but crosstalk between these processes is poorly understood. Here, we used single-cell RNA-Seq (scRNA-Seq) analysis to uncover the importance of the mitochondrial respiratory chain for ECM homeostasis in mature cartilage. This tissue produces large amounts of a specialized ECM to promote skeletal growth during development and maintain mobility throughout life. A combined approach of high-resolution scRNA-Seq, mass spectrometry/matrisome analysis, and atomic force microscopy was applied to mutant mice with cartilage-specific inactivation of respiratory chain function. This genetic inhibition in cartilage results in the expansion of a central area of 1-month-old mouse femur head cartilage, showing disorganized chondrocytes and increased deposition of ECM material. scRNA-Seq analysis identified a cell cluster-specific decrease in mitochondrial DNA-encoded respiratory chain genes and a unique regulation of ECM-related genes in nonarticular chondrocytes. These changes were associated with alterations in ECM composition, a shift in collagen/noncollagen protein content, and an increase of collagen crosslinking and ECM stiffness. These results demonstrate that mitochondrial respiratory chain dysfunction is a key factor that can promote ECM integrity and mechanostability in cartilage and presumably also in many other tissues.
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Affiliation(s)
- Kristina Bubb
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany; Center for Biochemistry, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Tatjana Holzer
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany; Center for Biochemistry, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Janica L Nolte
- Institute of Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Marcus Krüger
- Institute of Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Richard Wilson
- Central Science Laboratory, University of Tasmania, Hobart, Tasmania, Australia
| | - Ursula Schlötzer-Schrehardt
- Department of Ophthalmology, University Hospital Erlangen, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Jürgen Brinckmann
- Department of Dermatology, Institute of Virology and Cell Biology, University of Lübeck, Lübeck, Germany
| | - Janine Altmüller
- Cologne Center for Genomics, University of Cologne, Cologne, Germany; Berlin Institute of Health at Charité, Core Facility Genomics, Berlin, Germany; Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Attila Aszodi
- Department for Orthopaedics and Trauma Surgery, Musculoskeletal University Center Munich (MUM), University Hospital, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Lutz Fleischhauer
- Department for Orthopaedics and Trauma Surgery, Musculoskeletal University Center Munich (MUM), University Hospital, Ludwig-Maximilians-University (LMU), Munich, Germany; Center for Applied Tissue Engineering and Regenerative Medicine, Munich University of Applied Sciences, Munich, Germany
| | - Hauke Clausen-Schaumann
- Center for Applied Tissue Engineering and Regenerative Medicine, Munich University of Applied Sciences, Munich, Germany
| | - Kristina Probst
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany; Center for Biochemistry, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Bent Brachvogel
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany; Center for Biochemistry, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany.
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4
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Rumyantseva A, Motori E, Trifunovic A. DARS2 is indispensable for Purkinje cell survival and protects against cerebellar ataxia. Hum Mol Genet 2021; 29:2845-2854. [PMID: 32766765 DOI: 10.1093/hmg/ddaa176] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 07/25/2020] [Accepted: 07/27/2020] [Indexed: 12/23/2022] Open
Abstract
Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation disorder (LBSL) arises from mutations in mitochondrial aspartyl-tRNA synthetase (DARS2) gene. The disease has a childhood or juvenile-onset and is clinically characterized by cerebellar ataxia, cognitive decline and distinct morphological abnormalities upon magnetic resonance imaging. We previously demonstrated that neurons and not adult myelin-producing cells are specifically sensitive to DARS2 loss, hence likely the primary culprit in LBSL disorder. We used conditional Purkinje cell (PCs)-specific Dars2 deletion to elucidate further the cell-type-specific contribution of this class of neurons to the cerebellar impairment observed in LBSL. We show that DARS2 depletion causes a severe mitochondrial dysfunction concomitant with a massive loss of PCs by the age of 15 weeks, thereby rapidly deteriorating motor skills. Our findings conclusively show that DARS2 is indispensable for PC survival and highlights the central role of neuroinflammation in DARS2-related PC degeneration.
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Affiliation(s)
- Anastasia Rumyantseva
- Institute for Mitochondrial Diseases and Aging, Medical Faculty, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Centre for Molecular Medicine (CMMC), University of Cologne, Cologne D-50931 , Germany
| | - Elisa Motori
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne D-50931, Germany
| | - Aleksandra Trifunovic
- Institute for Mitochondrial Diseases and Aging, Medical Faculty, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Centre for Molecular Medicine (CMMC), University of Cologne, Cologne D-50931 , Germany
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5
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Silva-Pinheiro P, Pardo-Hernández C, Reyes A, Tilokani L, Mishra A, Cerutti R, Li S, Rozsivalova DH, Valenzuela S, Dogan SA, Peter B, Fernández-Silva P, Trifunovic A, Prudent J, Minczuk M, Bindoff L, Macao B, Zeviani M, Falkenberg M, Viscomi C. DNA polymerase gamma mutations that impair holoenzyme stability cause catalytic subunit depletion. Nucleic Acids Res 2021; 49:5230-5248. [PMID: 33956154 PMCID: PMC8136776 DOI: 10.1093/nar/gkab282] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 03/29/2021] [Accepted: 04/08/2021] [Indexed: 01/31/2023] Open
Abstract
Mutations in POLG, encoding POLγA, the catalytic subunit of the mitochondrial DNA polymerase, cause a spectrum of disorders characterized by mtDNA instability. However, the molecular pathogenesis of POLG-related diseases is poorly understood and efficient treatments are missing. Here, we generate the PolgA449T/A449T mouse model, which reproduces the A467T change, the most common human recessive mutation of POLG. We show that the mouse A449T mutation impairs DNA binding and mtDNA synthesis activities of POLγ, leading to a stalling phenotype. Most importantly, the A449T mutation also strongly impairs interactions with POLγB, the accessory subunit of the POLγ holoenzyme. This allows the free POLγA to become a substrate for LONP1 protease degradation, leading to dramatically reduced levels of POLγA in A449T mouse tissues. Therefore, in addition to its role as a processivity factor, POLγB acts to stabilize POLγA and to prevent LONP1-dependent degradation. Notably, we validated this mechanism for other disease-associated mutations affecting the interaction between the two POLγ subunits. We suggest that targeting POLγA turnover can be exploited as a target for the development of future therapies.
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Affiliation(s)
- Pedro Silva-Pinheiro
- MRC/University of Cambridge Mitochondrial Biology Unit, Hills Road, CB2 0XY Cambridge, UK
| | - Carlos Pardo-Hernández
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Medicinaregatan 9A P.O. Box 440, SE405 30 Gothenburg, Sweden
| | - Aurelio Reyes
- MRC/University of Cambridge Mitochondrial Biology Unit, Hills Road, CB2 0XY Cambridge, UK
| | - Lisa Tilokani
- MRC/University of Cambridge Mitochondrial Biology Unit, Hills Road, CB2 0XY Cambridge, UK
| | - Anup Mishra
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Medicinaregatan 9A P.O. Box 440, SE405 30 Gothenburg, Sweden
| | - Raffaele Cerutti
- Department of Neurosciences, University of Padova, via Giustiniani, 2-35128 Padova, Italy
| | - Shuaifeng Li
- Center for Cancer Biology, Life Science of Institution, Zhejiang University, Hangzhou 310058, China
| | - Dieu-Hien Rozsivalova
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany
| | - Sebastian Valenzuela
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Medicinaregatan 9A P.O. Box 440, SE405 30 Gothenburg, Sweden
| | - Sukru A Dogan
- Department of Molecular Biology and Genetics, Center for Life Sciences and Technologies, Bogazici University, 34342 Istanbul, Turkey
| | - Bradley Peter
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Medicinaregatan 9A P.O. Box 440, SE405 30 Gothenburg, Sweden
| | - Patricio Fernández-Silva
- Biochemistry and Molecular and Cell Biology Department, University of Zaragoza, C/ Pedro Cerbuna s/n 50.009-Zaragoza, and Biocomputation and Complex Systems Physics Institute (BIFI), C/ Mariano Esquillor, 50.018-Zaragoza, Spain
| | - Aleksandra Trifunovic
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany
| | - Julien Prudent
- MRC/University of Cambridge Mitochondrial Biology Unit, Hills Road, CB2 0XY Cambridge, UK
| | - Michal Minczuk
- MRC/University of Cambridge Mitochondrial Biology Unit, Hills Road, CB2 0XY Cambridge, UK
| | - Laurence Bindoff
- Department of Clinical Medicine, University of Bergen, 5007 Bergen, Norway
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Jonas Lies vei 65, 5021 Bergen, Norway
| | - Bertil Macao
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Medicinaregatan 9A P.O. Box 440, SE405 30 Gothenburg, Sweden
| | - Massimo Zeviani
- Department of Neurosciences, University of Padova, via Giustiniani, 2-35128 Padova, Italy
- Venetian Institute of Molecular Medicine, via Orus 2-35128 Padova, Italy
| | - Maria Falkenberg
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Medicinaregatan 9A P.O. Box 440, SE405 30 Gothenburg, Sweden
| | - Carlo Viscomi
- Department of Biomedical Sciences, University of Padova, via Ugo Bassi 58/B-35131 Padova, Italy
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Wieckowski MR, Pronicki M, Karkucinska-Wieckowska A. Update on the Histoenzymatic Methods for Visualization of the Activity of Individual Mitochondrial Respiratory Chain Complexes in the Human Frozen Sections. Methods Mol Biol 2021; 2310:69-77. [PMID: 34095999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Investigation of mitochondrial metabolism perturbations and successful diagnosis of patients with mitochondrial abnormalities often requires assessment of human samples like muscle or liver biopsy as well as autopsy material. Immunohistochemical and histochemical examination is an important technique to investigate mitochondrial dysfunction that combined with spectrophotometric and Blue Native electrophoresis techniques can be an important tool to provide diagnosis of mitochondrial disorders. In this chapter, we focus on technical description of the methods that are suitable to detect the activity of complex I, II, and IV of mitochondrial respiratory chain in frozen sections of brain, heart, muscle, and liver biopsies/autopsy. The protocols provided can be useful not only for general assessment of mitochondrial activity in studied material, but they are also successfully used in the diagnostic procedures in case of suspicion of mitochondrial disorders. In the age of high-performance NGS sequencing, these methods can be used to confirm whether mutations are pathogenic by proving their impact on the activity of individual respiratory chain complexes.
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Affiliation(s)
- Mariusz R Wieckowski
- Laboratory of Mitochondrial Biology and Metabolism Nencki Institute of Experimental Biology, Warsaw, Poland
| | - Maciej Pronicki
- Department of Pathomorphology, The Children's Memorial Health Institute, Warsaw, Poland
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Brunetti D, Bottani E, Segala A, Marchet S, Rossi F, Orlando F, Malavolta M, Carruba MO, Lamperti C, Provinciali M, Nisoli E, Valerio A. Targeting Multiple Mitochondrial Processes by a Metabolic Modulator Prevents Sarcopenia and Cognitive Decline in SAMP8 Mice. Front Pharmacol 2020; 11:1171. [PMID: 32848778 PMCID: PMC7411305 DOI: 10.3389/fphar.2020.01171] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 07/17/2020] [Indexed: 12/31/2022] Open
Abstract
The age-dependent declines of skeletal muscle and cognitive functions often coexist in elderly subjects. The underlying pathophysiological mechanisms share common features of mitochondrial dysfunction, which plays a central role in the development of overt sarcopenia and/or dementia. Dietary supplementation with formulations of essential and branched-chain amino acids (EAA-BCAA) is a promising preventive strategy because it can preserve mitochondrial biogenesis and function. The senescence-accelerated mouse prone 8 (SAMP8) is considered an accurate model of age-related muscular and cognitive alterations. Hence, we aimed to investigate the progression of mitochondrial dysfunctions during muscular and cognitive aging of SAMP8 mice and to study the effects of a novel EAA-BCAA-based metabolic modulator on these changes. We evaluated body condition, motor endurance, and working memory of SAMP8 mice at 5, 9, 12, and 15 months of age. Parallel changes in protein levels of mitochondrial respiratory chain subunits, regulators of mitochondrial biogenesis and dynamics, and the antioxidant response, as well as respiratory complex activities, were measured in the quadriceps femoris and the hippocampus. The same variables were assessed in 12-month-old SAMP8 mice that had received dietary supplementation with the novel EAA-BCAA formulation, containing tricarboxylic acid cycle intermediates and co-factors (PD-0E7, 1.5 mg/kg/body weight/day in drinking water) for 3 months. Contrary to untreated mice, which had a significant molecular and phenotypic impairment, PD-0E7-treated mice showed preserved healthy body condition, muscle weight to body weight ratio, motor endurance, and working memory at 12 months of age. The PD-0E7 mixture increased the protein levels and the enzymatic activities of mitochondrial complex I, II, and IV and the expression of proliferator-activated receptor γ coactivator-1α, optic atrophy protein 1, and nuclear factor, erythroid 2 like 2 in muscles and hippocampi. The mitochondrial amyloid-β-degrading pitrilysin metallopeptidase 1 was upregulated, while amyloid precursor protein was reduced in the hippocampi of PD-0E7 treated mice. In conclusion, we show that a dietary supplement tailored to boost mitochondrial respiration preserves skeletal muscle and hippocampal mitochondrial quality control and health. When administered at the early onset of age-related physical and cognitive decline, this novel metabolic inducer counteracts the deleterious effects of precocious aging in both domains.
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Affiliation(s)
- Dario Brunetti
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy.,Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico C. Besta, Milan, Italy
| | - Emanuela Bottani
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.,Department of Diagnostics and Public Health, University of Verona, Verona, Italy
| | - Agnese Segala
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico C. Besta, Milan, Italy
| | - Silvia Marchet
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico C. Besta, Milan, Italy
| | - Fabio Rossi
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Fiorenza Orlando
- Advanced Technology Center for Aging Research, Scientific Technological Area, IRCCS INRCA, Ancona, Italy
| | - Marco Malavolta
- Advanced Technology Center for Aging Research, Scientific Technological Area, IRCCS INRCA, Ancona, Italy
| | - Michele O Carruba
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy.,Center for Study and Research on Obesity, University of Milan, Milan, Italy
| | - Costanza Lamperti
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico C. Besta, Milan, Italy
| | - Mauro Provinciali
- Advanced Technology Center for Aging Research, Scientific Technological Area, IRCCS INRCA, Ancona, Italy
| | - Enzo Nisoli
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy.,Center for Study and Research on Obesity, University of Milan, Milan, Italy
| | - Alessandra Valerio
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
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8
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Marchet S, Legati A, Nasca A, Di Meo I, Spagnolo M, Zanetti N, Lamantea E, Catania A, Lamperti C, Ghezzi D. Homozygous mutations in C1QBP as cause of progressive external ophthalmoplegia (PEO) and mitochondrial myopathy with multiple mtDNA deletions. Hum Mutat 2020; 41:1745-1750. [PMID: 32652806 DOI: 10.1002/humu.24081] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/05/2020] [Accepted: 07/09/2020] [Indexed: 12/13/2022]
Abstract
Biallelic mutations in the C1QBP gene have been associated with mitochondrial cardiomyopathy and combined respiratory-chain deficiencies, with variable onset (including intrauterine or neonatal forms), phenotypes, and severity. We studied two unrelated adult patients from consanguineous families, presenting with progressive external ophthalmoplegia (PEO), mitochondrial myopathy, and without any heart involvement. Muscle biopsies from both patients showed typical mitochondrial alterations and the presence of multiple mitochondrial DNA deletions, whereas biochemical defects of the respiratory chain were present only in one subject. Using next-generation sequencing approaches, we identified homozygous mutations in C1QBP. Immunoblot analyses in patients' muscle samples revealed a strong reduction in the amount of the C1QBP protein and varied impairment of respiratory chain complexes, correlating with disease severity. Despite the original study indicated C1QBP mutations as causative for mitochondrial cardiomyopathy, our data indicate that mutations in C1QBP have to be considered in subjects with PEO phenotype or primary mitochondrial myopathy and without cardiomyopathy.
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Affiliation(s)
- Silvia Marchet
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Andrea Legati
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Alessia Nasca
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Ivano Di Meo
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Manuela Spagnolo
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Nadia Zanetti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Eleonora Lamantea
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Alessia Catania
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Costanza Lamperti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Daniele Ghezzi
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy.,Dipartimento di Fisiopatologia Medico-Chirurgica e dei Trapianti, Università degli Studi di Milano, Milano, Italy
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9
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The Impact of Mitochondrial Dysfunction on Dopaminergic Neurons in the Olfactory Bulb and Odor Detection. Mol Neurobiol 2020; 57:3646-3657. [PMID: 32564285 PMCID: PMC7398899 DOI: 10.1007/s12035-020-01947-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 05/13/2020] [Indexed: 01/27/2023]
Abstract
Understanding non-motor symptoms of Parkinson’s disease is important in order to unravel the underlying molecular mechanisms of the disease. Olfactory dysfunction is an early stage, non-motor symptom which occurs in 95% of Parkinson’s disease patients. Mitochondrial dysfunction is a key feature in Parkinson’s disease and importantly contributes to the selective loss of dopaminergic neurons the substantia nigra pars compacta. The olfactory bulb, the first olfactory processing station, also contains dopaminergic neurons, which modulate odor information and thereby enable odor detection as well as odor discrimination. MitoPark mice are a genetic model for Parkinson’s disease with severe mitochondrial dysfunction, reproducing the differential vulnerability of dopaminergic neurons in the midbrain. These animals were used to investigate the impact of mitochondrial dysfunction on olfactory-related behavior and olfactory bulb dopaminergic neuron survival. Odor detection was severely impaired in MitoPark mice. Interestingly, only the small anaxonic dopaminergic subpopulation, which is continuously replenished by neurogenesis, was moderately reduced in number, much less compared with dopaminergic neurons in the midbrain. As a potential compensatory response, an enhanced mobilization of progenitor cells was found in the subventricular zone. These results reveal a high robustness of dopaminergic neurons located in the olfactory bulb towards mitochondrial impairment, in striking contrast to their midbrain counterparts.
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10
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Cassina L, Chiaravalli M, Boletta A. Increased mitochondrial fragmentation in polycystic kidney disease acts as a modifier of disease progression. FASEB J 2020; 34:6493-6507. [PMID: 32239723 DOI: 10.1096/fj.201901739rr] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 02/17/2020] [Accepted: 03/06/2020] [Indexed: 12/23/2022]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is a common monogenic disorder, characterized by bilateral renal cyst formation. Multiple pathways are de-regulated in cystic epithelia offering good opportunities for therapy. Others and we have previously reported that metabolic reprogramming, including alterations of the TCA cycle, are prominent features of ADPKD. Several lines of evidence suggest that mitochondrial impairment might be responsible for the metabolic alterations. Here, we performed morphologic and morphometric evaluation of mitochondria by TEM in an orthologous mouse model of PKD caused by mutations in the Pkd1 gene (Ksp-Cre;Pkd1flox/- ). Furthermore, we measured mitochondrial respiration by COX and SDH enzymatic activity in situ. We found several alterations including reduced mitochondrial mass, altered structure and fragmentation of the mitochondrial network in cystic epithelia of Ksp-Cre;Pkd1flox/- mice. At the molecular level, we found reduced expression of the pro-fusion proteins OPA1 and MFN1 and up-regulation of the pro-fission protein DRP1. Importantly, administration of Mdivi-1, which interferes with DRP1 rescuing mitochondrial fragmentation, significantly reduced kidney/body weight, cyst formation, and improved renal function in Ksp-Cre;Pkd1flox/- mice. Our data indicate that impaired mitochondrial structure and function play a role in disease progression, and that their improvement can significantly modify the course of the disease.
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Affiliation(s)
- Laura Cassina
- Molecular Basis of Cystic Kidney Disorders Unit, Division of Genetics and Cell Biology, IRCCS-San Raffaele Scientific Institute, Milan, Italy
| | - Marco Chiaravalli
- Molecular Basis of Cystic Kidney Disorders Unit, Division of Genetics and Cell Biology, IRCCS-San Raffaele Scientific Institute, Milan, Italy
| | - Alessandra Boletta
- Molecular Basis of Cystic Kidney Disorders Unit, Division of Genetics and Cell Biology, IRCCS-San Raffaele Scientific Institute, Milan, Italy
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11
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Zhunina OA, Yabbarov NG, Grechko AV, Yet SF, Sobenin IA, Orekhov AN. Neurodegenerative Diseases Associated with Mitochondrial DNA Mutations. Curr Pharm Des 2020; 26:103-109. [DOI: 10.2174/1381612825666191122091320] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 11/19/2019] [Indexed: 01/23/2023]
Abstract
Mitochondrial dysfunction underlies several human chronic pathologies, including cardiovascular
disorders, cancers and neurodegenerative diseases. Impaired mitochondrial function associated with oxidative
stress can be a result of both nuclear and mitochondrial DNA (mtDNA) mutations. Neurological disorders associated
with mtDNA mutations include mitochondrial encephalomyopathy, chronic progressive external ophthalmoplegia,
neurogenic weakness, and Leigh syndrome. Moreover, mtDNA mutations were shown to play a role in the
development of Parkinson and Alzheimer’s diseases. In this review, current knowledge on the distribution and
possible roles of mtDNA mutations in the onset and development of various neurodegenerative diseases, with
special focus on Parkinson’s and Alzheimer’s diseases has been discussed.
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Affiliation(s)
- Olga A. Zhunina
- Russian Research Center for Molecular Diagnostics and Therapy, Simferopolsky Blvd., 8, 117149, Moscow, Russian Federation
| | - Nikita G. Yabbarov
- Russian Research Center for Molecular Diagnostics and Therapy, Simferopolsky Blvd., 8, 117149, Moscow, Russian Federation
| | - Andrey V. Grechko
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, 14-3 Solyanka Street, 109240, Moscow, Russian Federation
| | - Shaw-Fang Yet
- Institute of Cellular and System Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan Town, Miaoli County 35053, Taiwan
| | - Igor A. Sobenin
- Laboratory of Medical Genetics, National Medical Research Center of Cardiology, 15A 3rd Cherepkovskaya Street, Moscow 121552, Russian Federation
| | - Alexander N. Orekhov
- Institute of Human Morphology, 3 Tsyurupa Street, Moscow 117418, Russian Federation
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12
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Mitochondrial Dysfunction Combined with High Calcium Load Leads to Impaired Antioxidant Defense Underlying the Selective Loss of Nigral Dopaminergic Neurons. J Neurosci 2020; 40:1975-1986. [PMID: 32005765 DOI: 10.1523/jneurosci.1345-19.2019] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 10/15/2019] [Accepted: 11/24/2019] [Indexed: 12/13/2022] Open
Abstract
Mitochondrial dysfunction is critically involved in Parkinson's disease, characterized by loss of dopaminergic neurons (DaNs) in the substantia nigra (SNc), whereas DaNs in the neighboring ventral tegmental area (VTA) are much less affected. In contrast to VTA, SNc DaNs engage calcium channels to generate action potentials, which lead to oxidant stress by yet unknown pathways. To determine the molecular mechanisms linking calcium load with selective cell death in the presence of mitochondrial deficiency, we analyzed the mitochondrial redox state and the mitochondrial membrane potential in mice of both sexes with genetically induced, severe mitochondrial dysfunction in DaNs (MitoPark mice), at the same time expressing a redox-sensitive GFP targeted to the mitochondrial matrix. Despite mitochondrial insufficiency in all DaNs, exclusively SNc neurons showed an oxidized redox-system, i.e., a low reduced/oxidized glutathione (GSH-GSSG) ratio. This was mimicked by cyanide, but not by rotenone or antimycin A, making the involvement of reactive oxygen species rather unlikely. Surprisingly, a high mitochondrial inner membrane potential was maintained in MitoPark SNc DaNs. Antagonizing calcium influx into the cell and into mitochondria, respectively, rescued the disturbed redox ratio and induced further hyperpolarization of the inner mitochondrial membrane. Our data therefore show that the constant calcium load in SNc DaNs is counterbalanced by a high mitochondrial inner membrane potential, even under conditions of severe mitochondrial dysfunction, but triggers a detrimental imbalance in the mitochondrial redox system, which will lead to neuron death. Our findings thus reveal a new mechanism, redox imbalance, which underlies the differential vulnerability of DaNs to mitochondrial defects.SIGNIFICANCE STATEMENT Parkinson's disease is characterized by the preferential degeneration of dopaminergic neurons (DaNs) of the substantia nigra pars compacta (SNc), resulting in the characteristic hypokinesia in patients. Ubiquitous pathological triggers cannot be responsible for the selective neuron loss. Here we show that mitochondrial impairment together with elevated calcium burden destabilize the mitochondrial antioxidant defense only in SNc DaNs, and thus promote the increased vulnerability of this neuron population.
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13
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Ripolone M, Lucchini V, Ronchi D, Fagiolari G, Bordoni A, Fortunato F, Mondello S, Bonato S, Meregalli M, Torrente Y, Corti S, Comi GP, Moggio M, Sciacco M. Purkinje cell COX deficiency and mtDNA depletion in an animal model of spinocerebellar ataxia type 1. J Neurosci Res 2019; 96:1576-1585. [PMID: 30113722 DOI: 10.1002/jnr.24263] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 05/09/2018] [Accepted: 05/09/2018] [Indexed: 12/19/2022]
Abstract
Spinocerebellar ataxias (SCAs) are a genetically heterogeneous group of cerebellar degenerative disorders, characterized by progressive gait unsteadiness, hand incoordination, and dysarthria. Ataxia type 1 (SCA1) is caused by the expansion of a CAG trinucleotide repeat in the SCA1 gene resulting in the atypical extension of a polyglutamine (polyQ) tract within the ataxin-1 protein. Our main objective was to investigate the mitochondrial oxidative metabolism in the cerebellum of transgenic SCA1 mice. SCA1 transgenic mice develop clinical features in the early life stages (around 5 weeks of age) presenting pathological cerebellar signs with concomitant progressive Purkinje neuron atrophy and relatively little cell loss; this evidence suggests that the SCA1 phenotype is not the result of cell death per se, but a possible effect of cellular dysfunction that occurs before neuronal demise. We studied the mitochondrial oxidative metabolism in cerebellar cells from both homozygous and heterozygous transgenic SCA1 mice, aged 2 and 6 months. Histochemical examination showed a cytochrome-c-oxidase (COX) deficiency in the Purkinje cells (PCs) of both heterozygous and homozygous mice, the oxidative defect being more prominent in older mice, in which the percentage of COX-deficient PC was up to 30%. Using a laser-microdissector, we evaluated the mitochondrial DNA (mtDNA) content on selectively isolated COX-competent and COX-deficient PC by quantitative Polymerase Chain Reaction and we found mtDNA depletion in those with oxidative dysfunction. In conclusion, the selective oxidative metabolism defect observed in neuronal PC expressing mutant ataxin occurs as early as 8 weeks of age thus representing an early step in the PC degeneration process in SCA1 disease.
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Affiliation(s)
- Michela Ripolone
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Valeria Lucchini
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Dario Ronchi
- Neurology Unit, Neuroscience Section, Department of Pathophysiology and Transplantation, Dino Ferrari Centre, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Gigliola Fagiolari
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Andreina Bordoni
- Neurology Unit, Neuroscience Section, Department of Pathophysiology and Transplantation, Dino Ferrari Centre, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Francesco Fortunato
- Neurology Unit, Neuroscience Section, Department of Pathophysiology and Transplantation, Dino Ferrari Centre, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Stefania Mondello
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy
| | - Sara Bonato
- Neurology Unit, Neuroscience Section, Department of Pathophysiology and Transplantation, Dino Ferrari Centre, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Mirella Meregalli
- Department of Pathophysiology and Transplantation, Stem Cell Laboratory, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico di Milano, Centro Dino Ferrari, Milan, Italy
| | - Yvan Torrente
- Department of Pathophysiology and Transplantation, Stem Cell Laboratory, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico di Milano, Centro Dino Ferrari, Milan, Italy
| | - Stefania Corti
- Neurology Unit, Neuroscience Section, Department of Pathophysiology and Transplantation, Dino Ferrari Centre, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Giacomo P Comi
- Neurology Unit, Neuroscience Section, Department of Pathophysiology and Transplantation, Dino Ferrari Centre, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Maurizio Moggio
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Monica Sciacco
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
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14
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Holzer T, Probst K, Etich J, Auler M, Georgieva VS, Bluhm B, Frie C, Heilig J, Niehoff A, Nüchel J, Plomann M, Seeger JM, Kashkar H, Baris OR, Wiesner RJ, Brachvogel B. Respiratory chain inactivation links cartilage-mediated growth retardation to mitochondrial diseases. J Cell Biol 2019; 218:1853-1870. [PMID: 31085560 PMCID: PMC6548139 DOI: 10.1083/jcb.201809056] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 01/12/2019] [Accepted: 04/12/2019] [Indexed: 12/17/2022] Open
Abstract
Children with mitochondrial diseases often present with slow growth and short stature, but the underlying mechanism remains unclear. In this study, Holzer et al. provide in vivo evidence that mitochondrial respiratory chain dysfunction induces cartilage degeneration coincident with altered metabolism, impaired extracellular matrix formation, and cell death at the cartilage–bone junction. In childhood, skeletal growth is driven by transient expansion of cartilage in the growth plate. The common belief is that energy production in this hypoxic tissue mainly relies on anaerobic glycolysis and not on mitochondrial respiratory chain (RC) activity. However, children with mitochondrial diseases causing RC dysfunction often present with short stature, which indicates that RC activity may be essential for cartilage-mediated skeletal growth. To elucidate the role of the mitochondrial RC in cartilage growth and pathology, we generated mice with impaired RC function in cartilage. These mice develop normally until birth, but their later growth is retarded. A detailed molecular analysis revealed that metabolic signaling and extracellular matrix formation is disturbed and induces cell death at the cartilage–bone junction to cause a chondrodysplasia-like phenotype. Hence, the results demonstrate the overall importance of the metabolic switch from fetal glycolysis to postnatal RC activation in growth plate cartilage and explain why RC dysfunction can cause short stature in children with mitochondrial diseases.
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Affiliation(s)
- Tatjana Holzer
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, Cologne, Germany.,Center for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Kristina Probst
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, Cologne, Germany.,Center for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Julia Etich
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, Cologne, Germany.,Center for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Markus Auler
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, Cologne, Germany.,Center for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Veronika S Georgieva
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, Cologne, Germany.,Center for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Björn Bluhm
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, Cologne, Germany.,Center for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Christian Frie
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, Cologne, Germany.,Center for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Juliane Heilig
- Institute of Biomechanics and Orthopedics, German Sport University Cologne, Cologne, Germany.,Cologne Center for Musculoskeletal Biomechanics, University of Cologne, Cologne, Germany
| | - Anja Niehoff
- Institute of Biomechanics and Orthopedics, German Sport University Cologne, Cologne, Germany.,Cologne Center for Musculoskeletal Biomechanics, University of Cologne, Cologne, Germany
| | - Julian Nüchel
- Center for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Markus Plomann
- Center for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Jens M Seeger
- Institute for Medical Microbiology, Immunology, and Hygiene, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Hamid Kashkar
- Institute for Medical Microbiology, Immunology, and Hygiene, Faculty of Medicine, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany.,Center of Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Olivier R Baris
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Rudolf J Wiesner
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany.,Center of Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Bent Brachvogel
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, Cologne, Germany .,Center for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
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15
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De Toni L, Agoulnik AI, Sandri M, Foresta C, Ferlin A. INSL3 in the muscolo-skeletal system. Mol Cell Endocrinol 2019; 487:12-17. [PMID: 30625346 DOI: 10.1016/j.mce.2018.12.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 12/27/2018] [Accepted: 12/31/2018] [Indexed: 12/23/2022]
Abstract
Bone and skeletal muscle are currently considered a unified functional unit, showing complementary regulation at mechanical, biochemical, paracrine and metabolic levels. This functional unit undergoes a central hormonal regulation which is mainly ascribed to sex steroids and, in particular, androgens. However, recent evidence suggest that another testicular hormone lines the classical anabolic effect of testosterone on bone and muscle, the insulin-like peptide 3 (INSL3) acting on its specific receptor RXFP2. This minireview focuses on the most recent findings describing the role of INSL3/RXFP2 axis on the muscolo-skeletal system, from the mechanistic insights to the phenotypic consequences. Pathophysiological and therapeutic widenings deriving from available data are also discussed.
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Affiliation(s)
- Luca De Toni
- Department of Medicine, University of Padova, Via Giustiniani 2, 35121, Padova, Italy.
| | - Alexander I Agoulnik
- Department of Human and Molecular Genetics, Herbert Wertheim College of Medicine, Florida International University, 11200 SW 8th Street, 33199, Miami, FL, USA.
| | - Marco Sandri
- Department of Biomedical Sciences, University of Padova, Via Colombo 3, 35100, Padova, Italy; Venetian Institute of Molecular Medicine, Via Orus 2, 35129, Padova, Italy.
| | - Carlo Foresta
- Department of Medicine, University of Padova, Via Giustiniani 2, 35121, Padova, Italy.
| | - Alberto Ferlin
- Unit of Endocrinology, Department of Clinical and Experimental Sciences, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
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16
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Bugiardini E, Mitchell AL, Rosa ID, Horning-Do HT, Pitmann AM, Poole OV, Holton JL, Shah S, Woodward C, Hargreaves I, Quinlivan R, Amunts A, Wiesner RJ, Houlden H, Holt IJ, Hanna MG, Pitceathly RDS, Spinazzola A. MRPS25 mutations impair mitochondrial translation and cause encephalomyopathy. Hum Mol Genet 2019; 28:2711-2719. [PMID: 31039582 PMCID: PMC6687946 DOI: 10.1093/hmg/ddz093] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 04/25/2019] [Accepted: 04/25/2019] [Indexed: 12/22/2022] Open
Abstract
Mitochondrial disorders are clinically and genetically heterogeneous and are associated with a variety of disease mechanisms. Defects of mitochondrial protein synthesis account for the largest subgroup of disorders manifesting with impaired respiratory chain capacity; yet, only a few have been linked to dysfunction in the protein components of the mitochondrial ribosomes. Here, we report a subject presenting with dyskinetic cerebral palsy and partial agenesis of the corpus callosum, while histochemical and biochemical analyses of skeletal muscle revealed signs of mitochondrial myopathy. Using exome sequencing, we identified a homozygous variant c.215C>T in MRPS25, which encodes for a structural component of the 28S small subunit of the mitochondrial ribosome (mS25). The variant segregated with the disease and substitutes a highly conserved proline residue with leucine (p.P72L) that, based on the high-resolution structure of the 28S ribosome, is predicted to compromise inter-protein contacts and destabilize the small subunit. Concordant with the in silico analysis, patient’s fibroblasts showed decreased levels of MRPS25 and other components of the 28S subunit. Moreover, assembled 28S subunits were scarce in the fibroblasts with mutant mS25 leading to impaired mitochondrial translation and decreased levels of multiple respiratory chain subunits. Crucially, these abnormalities were rescued by transgenic expression of wild-type MRPS25 in the mutant fibroblasts. Collectively, our data demonstrate the pathogenicity of the p.P72L variant and identify MRPS25 mutations as a new cause of mitochondrial translation defect.
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Affiliation(s)
- Enrico Bugiardini
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Alice L Mitchell
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Royal Free Campus, London NW3 2PF, UK
| | - Ilaria Dalla Rosa
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Royal Free Campus, London NW3 2PF, UK
| | - Hue-Tran Horning-Do
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty, University of Köln, 50931 Köln, Germany
| | - Alan M Pitmann
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Olivia V Poole
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Janice L Holton
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Sachit Shah
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Cathy Woodward
- Neurogenetic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Iain Hargreaves
- Neurometabolic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Rosaline Quinlivan
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Alexey Amunts
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165 Solna, Sweden
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Rudolf J Wiesner
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty, University of Köln, 50931 Köln, Germany
| | - Henry Houlden
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Ian J Holt
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Royal Free Campus, London NW3 2PF, UK
- Biodonostia Health Research Institute, 20014 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
- CIBERNED (Center for Networked Biomedical Research on Neurodegenerative Diseases, Ministry of Economy and Competitiveness, Institute Carlos III), Madrid, Spain
| | - Michael G Hanna
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Robert D S Pitceathly
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Antonella Spinazzola
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Royal Free Campus, London NW3 2PF, UK
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17
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Alteration of mitochondrial membrane inner potential in three Italian patients with megaconial congenital muscular dystrophy carrying new mutations in CHKB gene. Mitochondrion 2019; 47:24-29. [PMID: 30986505 DOI: 10.1016/j.mito.2019.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 02/09/2019] [Accepted: 04/10/2019] [Indexed: 11/20/2022]
Abstract
Congenital Muscular Dystrophies (CMDs) are a heterogeneous group of autosomal recessive disorders presenting at birth with psychomotor delay, cognitive impairment, muscle weakness and hypotonia. Here we described an alteration of mitochondrial inner membrane potential and mitochondrial network in cells derived from Italian patients carrying three novel mutations in CHKB gene, recently associated with "megaconial CMD". On the bases of our findings, we hypothesize that the mitochondrial membrane potential alteration, presumably as a consequence of the altered biosynthesis of phosphatidylcholine, could be responsible for the peculiar morphological aspect of mitochondria in this disease and might be involved in the disease pathogenesis.
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18
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Signes A, Cerutti R, Dickson AS, Benincá C, Hinchy EC, Ghezzi D, Carrozzo R, Bertini E, Murphy MP, Nathan JA, Viscomi C, Fernandez-Vizarra E, Zeviani M. APOPT1/COA8 assists COX assembly and is oppositely regulated by UPS and ROS. EMBO Mol Med 2019; 11:e9582. [PMID: 30552096 PMCID: PMC6328941 DOI: 10.15252/emmm.201809582] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 11/20/2018] [Accepted: 11/21/2018] [Indexed: 02/02/2023] Open
Abstract
Loss-of-function mutations in APOPT1, a gene exclusively found in higher eukaryotes, cause a characteristic type of cavitating leukoencephalopathy associated with mitochondrial cytochrome c oxidase (COX) deficiency. Although the genetic association of APOPT1 pathogenic variants with isolated COX defects is now clear, the biochemical link between APOPT1 function and COX has remained elusive. We investigated the molecular role of APOPT1 using different approaches. First, we generated an Apopt1 knockout mouse model which shows impaired motor skills, e.g., decreased motor coordination and endurance, associated with reduced COX activity and levels in multiple tissues. In addition, by achieving stable expression of wild-type APOPT1 in control and patient-derived cultured cells we ruled out a role of this protein in apoptosis and established instead that this protein is necessary for proper COX assembly and function. On the other hand, APOPT1 steady-state levels were shown to be controlled by the ubiquitination-proteasome system (UPS). Conversely, in conditions of increased oxidative stress, APOPT1 is stabilized, increasing its mature intramitochondrial form and thereby protecting COX from oxidatively induced degradation.
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Affiliation(s)
- Alba Signes
- MRC-Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Raffaele Cerutti
- MRC-Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Anna S Dickson
- Department of Medicine, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Cristiane Benincá
- MRC-Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | | | - Daniele Ghezzi
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Rosalba Carrozzo
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesù Children's Research Hospital, IRCCS, Rome, Italy
| | - Enrico Bertini
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesù Children's Research Hospital, IRCCS, Rome, Italy
| | - Michael P Murphy
- MRC-Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - James A Nathan
- Department of Medicine, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Carlo Viscomi
- MRC-Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | | | - Massimo Zeviani
- MRC-Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
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19
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Civiletto G, Dogan SA, Cerutti R, Fagiolari G, Moggio M, Lamperti C, Benincá C, Viscomi C, Zeviani M. Rapamycin rescues mitochondrial myopathy via coordinated activation of autophagy and lysosomal biogenesis. EMBO Mol Med 2018; 10:emmm.201708799. [PMID: 30309855 PMCID: PMC6220341 DOI: 10.15252/emmm.201708799] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The mTOR inhibitor rapamycin ameliorates the clinical and biochemical phenotype of mouse, worm, and cellular models of mitochondrial disease, via an unclear mechanism. Here, we show that prolonged rapamycin treatment improved motor endurance, corrected morphological abnormalities of muscle, and increased cytochrome c oxidase (COX) activity of a muscle-specific Cox15 knockout mouse (Cox15sm/sm ). Rapamycin treatment restored autophagic flux, which was impaired in naïve Cox15sm/sm muscle, and reduced the number of damaged mitochondria, which accumulated in untreated Cox15sm/sm mice. Conversely, rilmenidine, an mTORC1-independent autophagy inducer, was ineffective on the myopathic features of Cox15sm/sm animals. This stark difference supports the idea that inhibition of mTORC1 by rapamycin has a key role in the improvement of the mitochondrial function in Cox15sm/sm muscle. In contrast to rilmenidine, rapamycin treatment also activated lysosomal biogenesis in muscle. This effect was associated with increased nuclear localization of TFEB, a master regulator of lysosomal biogenesis, which is inhibited by mTORC1-dependent phosphorylation. We propose that the coordinated activation of autophagic flux and lysosomal biogenesis contribute to the effective clearance of dysfunctional mitochondria by rapamycin.
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Affiliation(s)
| | - Sukru Anil Dogan
- MRC Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
| | - Raffaele Cerutti
- MRC Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
| | - Gigliola Fagiolari
- Neuromuscular and Rare Diseases UnitFondazione IRCCS Ca’ Granda Ospedale Maggiore PoliclinicoMilanItaly
| | - Maurizio Moggio
- Neuromuscular and Rare Diseases UnitFondazione IRCCS Ca’ Granda Ospedale Maggiore PoliclinicoMilanItaly
| | | | | | - Carlo Viscomi
- MRC Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
| | - Massimo Zeviani
- MRC Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
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20
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Borsani O, Piga D, Costa S, Govoni A, Magri F, Artoni A, Cinnante CM, Fagiolari G, Ciscato P, Moggio M, Bresolin N, Comi GP, Corti S. Stormorken Syndrome Caused by a p.R304W STIM1 Mutation: The First Italian Patient and a Review of the Literature. Front Neurol 2018; 9:859. [PMID: 30374325 PMCID: PMC6196270 DOI: 10.3389/fneur.2018.00859] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 09/24/2018] [Indexed: 11/30/2022] Open
Abstract
Stormorken syndrome is a rare autosomal dominant disease that is characterized by a complex phenotype that includes tubular aggregate myopathy (TAM), bleeding diathesis, hyposplenism, mild hypocalcemia and additional features, such as miosis and a mild intellectual disability (dyslexia). Stormorken syndrome is caused by autosomal dominant mutations in the STIM1 gene, which encodes an endoplasmic reticulum Ca2+ sensor. Here, we describe the clinical and molecular aspects of a 21-year-old Italian female with Stormorken syndrome. The STIM1 gene sequence identified a c.910C > T transition in a STIM1 allele (p.R304W). The p.R304W mutation is a common mutation that is responsible for Stormorken syndrome and is hypothesized to cause a gain of function action associated with a rise in Ca2+ levels. A review of published STIM1 mutations (n = 50) and reported Stormorken patients (n = 11) indicated a genotype-phenotype correlation with mutations in a coiled coil cytoplasmic domain associated with complete Stormorken syndrome, and other pathological variants outside this region were more often linked to an incomplete phenotype. Our study describes the first Italian patient with Stormorken syndrome, contributes to the genotype/phenotype correlation and highlights the possibility of directly investigating the p.R304W mutation in the presence of a typical phenotype. Highlights- Stormorken syndrome is a rare autosomal dominant disease. - Stormoken syndrome is caused by autosomal dominant mutations in the STIM1 gene. - We present the features of a 21-year-old Italian female with Stormorken syndrome. - Our review of published STIM1 mutations suggests a genotype-phenotype correlation. - The p.R304W mutation should be investigated in the presence of a typical phenotype.
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Affiliation(s)
- Oscar Borsani
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Daniela Piga
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Stefania Costa
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Alessandra Govoni
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Francesca Magri
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Andrea Artoni
- A. Bianchi Bonomi Hemophilia and Thrombosis Center, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Claudia M Cinnante
- Neuroradiology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Gigliola Fagiolari
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Patrizia Ciscato
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Maurizio Moggio
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Nereo Bresolin
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Neuroscience Section, Department of Pathophysiology and Transplantation, Dino Ferrari Centre, University of Milan, Milan, Italy
| | - Giacomo P Comi
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Neuroscience Section, Department of Pathophysiology and Transplantation, Dino Ferrari Centre, University of Milan, Milan, Italy
| | - Stefania Corti
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Neuroscience Section, Department of Pathophysiology and Transplantation, Dino Ferrari Centre, University of Milan, Milan, Italy
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21
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Wischhof L, Gioran A, Sonntag-Bensch D, Piazzesi A, Stork M, Nicotera P, Bano D. A disease-associated Aifm1 variant induces severe myopathy in knockin mice. Mol Metab 2018; 13:10-23. [PMID: 29780003 PMCID: PMC6026322 DOI: 10.1016/j.molmet.2018.05.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 05/02/2018] [Accepted: 05/03/2018] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVE Mutations in the AIFM1 gene have been identified in recessive X-linked mitochondrial diseases. Functional and molecular consequences of these pathogenic AIFM1 mutations have been poorly studied in vivo. METHODS/RESULTS Here we provide evidence that the disease-associated apoptosis-inducing factor (AIF) deletion arginine 201 (R200 in rodents) causes pathology in knockin mice. Within a few months, posttranslational loss of the mutant AIF protein induces severe myopathy associated with a lower number of cytochrome c oxidase-positive muscle fibers. At a later stage, Aifm1 (R200 del) knockin mice manifest peripheral neuropathy, but they do not show neurodegenerative processes in the cerebellum, as observed in age-matched hypomorphic Harlequin (Hq) mutant mice. Quantitative proteomic and biochemical data highlight common molecular signatures of mitochondrial diseases, including aberrant folate-driven one-carbon metabolism and sustained Akt/mTOR signaling. CONCLUSION Our findings indicate metabolic defects and distinct tissue-specific vulnerability due to a disease-causing AIFM1 mutation, with many pathological hallmarks that resemble those seen in patients.
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Affiliation(s)
- Lena Wischhof
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Anna Gioran
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | | | - Antonia Piazzesi
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Miriam Stork
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | | | - Daniele Bano
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.
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22
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Fabbri A, Travaglione S, Maroccia Z, Guidotti M, Pierri CL, Primiano G, Servidei S, Loizzo S, Fiorentini C. The Bacterial Protein CNF1 as a Potential Therapeutic Strategy against Mitochondrial Diseases: A Pilot Study. Int J Mol Sci 2018; 19:E1825. [PMID: 29933571 PMCID: PMC6073533 DOI: 10.3390/ijms19071825] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 06/18/2018] [Indexed: 02/07/2023] Open
Abstract
The Escherichia coli protein toxin cytotoxic necrotizing factor 1 (CNF1), which acts on the Rho GTPases that are key regulators of the actin cytoskeleton, is emerging as a potential therapeutic tool against certain neurological diseases characterized by cellular energy homeostasis impairment. In this brief communication, we show explorative results on the toxin’s effect on fibroblasts derived from a patient affected by myoclonic epilepsy with ragged-red fibers (MERRF) that carries a mutation in the m.8344A>G gene of mitochondrial DNA. We found that, in the patient’s cells, besides rescuing the wild-type-like mitochondrial morphology, CNF1 administration is able to trigger a significant increase in cellular content of ATP and of the mitochondrial outer membrane marker Tom20. These results were accompanied by a profound F-actin reorganization in MERRF fibroblasts, which is a typical CNF1-induced effect on cell cytoskeleton. These results point at a possible role of the actin organization in preventing or limiting the cell damage due to mitochondrial impairment and at CNF1 treatment as a possible novel strategy against mitochondrial diseases still without cure.
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Affiliation(s)
- Alessia Fabbri
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Rome, Italy.
| | - Sara Travaglione
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Rome, Italy.
| | - Zaira Maroccia
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Rome, Italy.
| | - Marco Guidotti
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Rome, Italy.
| | - Ciro Leonardo Pierri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, via Orabona, 4, 70124 Bari, Italy.
| | - Guido Primiano
- Unità di Neurofisiopatologia, Area Neuroscienze, Università Cattolica del Sacro Cuore, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Largo Agostino Gemelli, 8, 00168 Rome, Italy.
| | - Serenella Servidei
- Unità di Neurofisiopatologia, Area Neuroscienze, Università Cattolica del Sacro Cuore, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Largo Agostino Gemelli, 8, 00168 Rome, Italy.
| | - Stefano Loizzo
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Rome, Italy.
| | - Carla Fiorentini
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Rome, Italy.
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23
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Quadalti C, Brunetti D, Lagutina I, Duchi R, Perota A, Lazzari G, Cerutti R, Di Meo I, Johnson M, Bottani E, Crociara P, Corona C, Grifoni S, Tiranti V, Fernandez-Vizarra E, Robinson AJ, Viscomi C, Casalone C, Zeviani M, Galli C. SURF1 knockout cloned pigs: Early onset of a severe lethal phenotype. Biochim Biophys Acta Mol Basis Dis 2018; 1864:2131-2142. [PMID: 29601977 PMCID: PMC6018622 DOI: 10.1016/j.bbadis.2018.03.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/28/2018] [Accepted: 03/22/2018] [Indexed: 12/15/2022]
Abstract
Leigh syndrome (LS) associated with cytochrome c oxidase (COX) deficiency is an early onset, fatal mitochondrial encephalopathy, leading to multiple neurological failure and eventually death, usually in the first decade of life. Mutations in SURF1, a nuclear gene encoding a mitochondrial protein involved in COX assembly, are among the most common causes of LS. LSSURF1 patients display severe, isolated COX deficiency in all tissues, including cultured fibroblasts and skeletal muscle. Recombinant, constitutive SURF1-/- mice show diffuse COX deficiency, but fail to recapitulate the severity of the human clinical phenotype. Pigs are an attractive alternative model for human diseases, because of their size, as well as metabolic, physiological and genetic similarity to humans. Here, we determined the complete sequence of the swine SURF1 gene, disrupted it in pig primary fibroblast cell lines using both TALENs and CRISPR/Cas9 genome editing systems, before finally generating SURF1-/- and SURF1-/+ pigs by Somatic Cell Nuclear Transfer (SCNT). SURF1-/- pigs were characterized by failure to thrive, muscle weakness and highly reduced life span with elevated perinatal mortality, compared to heterozygous SURF1-/+ and wild type littermates. Surprisingly, no obvious COX deficiency was detected in SURF1-/- tissues, although histochemical analysis revealed the presence of COX deficiency in jejunum villi and total mRNA sequencing (RNAseq) showed that several COX subunit-encoding genes were significantly down-regulated in SURF1-/- skeletal muscles. In addition, neuropathological findings, indicated a delay in central nervous system development of newborn SURF1-/- piglets. Our results suggest a broader role of sSURF1 in mitochondrial bioenergetics.
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Affiliation(s)
- C Quadalti
- Avantea, Laboratory of Reproductive Technologies, Via Porcellasco 7/f, Cremona 26100, Italy; Dept. of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell'Emilia, BO, Italy
| | - D Brunetti
- University of Cambridge/MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Rd, Cambridge CB20XY, UK
| | - I Lagutina
- Avantea, Laboratory of Reproductive Technologies, Via Porcellasco 7/f, Cremona 26100, Italy
| | - R Duchi
- Avantea, Laboratory of Reproductive Technologies, Via Porcellasco 7/f, Cremona 26100, Italy
| | - A Perota
- Avantea, Laboratory of Reproductive Technologies, Via Porcellasco 7/f, Cremona 26100, Italy
| | - G Lazzari
- Avantea, Laboratory of Reproductive Technologies, Via Porcellasco 7/f, Cremona 26100, Italy; Fondazione Avantea, Cremona, Italy
| | - R Cerutti
- University of Cambridge/MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Rd, Cambridge CB20XY, UK
| | - I Di Meo
- Neurologic Institute Carlo Besta, Via G. Celoria 11, 20133 Milan, Italy
| | - M Johnson
- University of Cambridge/MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Rd, Cambridge CB20XY, UK
| | - E Bottani
- University of Cambridge/MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Rd, Cambridge CB20XY, UK
| | - P Crociara
- Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Via Bologna 148, Torino 10154, Italy
| | - C Corona
- Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Via Bologna 148, Torino 10154, Italy
| | - S Grifoni
- Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Via Bologna 148, Torino 10154, Italy
| | - V Tiranti
- Neurologic Institute Carlo Besta, Via G. Celoria 11, 20133 Milan, Italy
| | - E Fernandez-Vizarra
- University of Cambridge/MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Rd, Cambridge CB20XY, UK
| | - A J Robinson
- University of Cambridge/MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Rd, Cambridge CB20XY, UK
| | - C Viscomi
- University of Cambridge/MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Rd, Cambridge CB20XY, UK
| | - C Casalone
- Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Via Bologna 148, Torino 10154, Italy
| | - M Zeviani
- University of Cambridge/MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Rd, Cambridge CB20XY, UK.
| | - C Galli
- Avantea, Laboratory of Reproductive Technologies, Via Porcellasco 7/f, Cremona 26100, Italy; Dept. of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell'Emilia, BO, Italy.
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24
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Toldo I, Nosadini M, Boscardin C, Talenti G, Manara R, Lamantea E, Legati A, Ghezzi D, Perilongo G, Sartori S. Neonatal mitochondrial leukoencephalopathy with brain and spinal involvement and high lactate: expanding the phenotype of ISCA2 gene mutations. Metab Brain Dis 2018; 33:805-812. [PMID: 29359243 DOI: 10.1007/s11011-017-0181-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Accepted: 12/27/2017] [Indexed: 02/04/2023]
Abstract
A homoallelic missense founder mutation of the iron-sulfur cluster assembly 2 (ISCA2) gene has been recently reported in six cases affected by an autosomal recessive infantile neurodegenerative mitochondrial disorder. We documented a case of a 2-month-old girl presenting with severe hypotonia and nystagmus, who rapidly deteriorated and died at the age of three months. Increased cerebral spinal fluid level of lactate, documented also at the brain spectroscopy, involvement of the cortex, restricted diffusion of white and gray matter abnormalities, sparing of the corpus callosum and extensive involvement of the spinal cord were observed. Her clinical presenting features and course as well as some neuroradiological findings mimicked those of early-onset leukoencephalopathy with brainstem and spinal cord involvement and high brain lactate (LBSL). The analysis of the mitochondrial respiratory chain function showed a reduced activity of complexes II and IV. The girl harboured two heterozygous mutations in the ISCA2 gene. A comprehensive review of the literature and a comparison with the cases of early onset LBSL enabled us to highlight significant differences in the clinical, biochemical and neuroradiological phenotype between the two conditions, which also emerged from the comparison with the other 6 reported cases of ISCA2 gene mutation previously reported. In summary, this represents the second report ever published associating ISCA2 gene mutation with a mitochondrial leukoencephalopathy, with a different genetic mechanism to the previous cases. Molecular analysis of ISCA2 should be included in the genetic panel for the diagnosis of early onset mitochondrial leukoencephalopathies.
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Affiliation(s)
- Irene Toldo
- Pediatric Neurology Unit, Department of Women's and Children's Health, University Hospital of Padua, Padua, Italy.
| | - Margherita Nosadini
- Pediatric Neurology Unit, Department of Women's and Children's Health, University Hospital of Padua, Padua, Italy
| | - Chiara Boscardin
- Pediatric Neurology Unit, Department of Women's and Children's Health, University Hospital of Padua, Padua, Italy
| | - Giacomo Talenti
- Neuroradiology Unit, Department of Neurological Sciences, University Hospital of Padua, Padua, Italy
| | - Renzo Manara
- Neuroradiology, University of Salerno, Salerno, Italy
| | - Eleonora Lamantea
- Unit of Molecular Neurogenetics, Foundation IRCCS Institute of Neurology 'Carlo Besta', Milan, Italy
| | - Andrea Legati
- Unit of Molecular Neurogenetics, Foundation IRCCS Institute of Neurology 'Carlo Besta', Milan, Italy
| | - Daniele Ghezzi
- Unit of Molecular Neurogenetics, Foundation IRCCS Institute of Neurology 'Carlo Besta', Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Giorgio Perilongo
- Pediatric Neurology Unit, Department of Women's and Children's Health, University Hospital of Padua, Padua, Italy
| | - Stefano Sartori
- Pediatric Neurology Unit, Department of Women's and Children's Health, University Hospital of Padua, Padua, Italy
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25
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Dölle C, Bindoff LA, Tzoulis C. 3,3'-Diaminobenzidine staining interferes with PCR-based DNA analysis. Sci Rep 2018; 8:1272. [PMID: 29352159 PMCID: PMC5775208 DOI: 10.1038/s41598-018-19745-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 01/08/2018] [Indexed: 11/09/2022] Open
Abstract
3,3'-Diaminobenzidine (DAB) is a widely used chromogen in histological staining methods and stained tissue is often used in downstream molecular analyses such as quantitative PCR (qPCR). Using microdissected muscle fibers from sequential muscle sections stained by DAB-dependent and -independent methods, we show that DAB exerts a strong inhibitory effect on qPCR-based mitochondrial DNA quantification. This effect introduces a significant bias in the estimation of mitochondrial DNA copy number and deletion levels between DAB-positive and -negative fibers. We reproduce our findings in microdissected neurons from human brain tissue, suggesting a general effect of DAB staining on PCR analyses independent of the underlying tissue or cell type. Using an exogenous DNA template added to tissue samples we provide evidence that DAB-staining predominantly interferes with the tissue-derived DNA template rather than inhibiting DNA polymerase activity. Our results suggest that DAB-based staining is incompatible with PCR-based quantification methods and some of the previously reported results employing this approach should be reconsidered.
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Affiliation(s)
- Christian Dölle
- Department of Neurology, Haukeland University Hospital, Bergen, Norway.,Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Laurence A Bindoff
- Department of Neurology, Haukeland University Hospital, Bergen, Norway.,Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Charalampos Tzoulis
- Department of Neurology, Haukeland University Hospital, Bergen, Norway. .,Department of Clinical Medicine, University of Bergen, Bergen, Norway.
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26
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Ferlin A, De Toni L, Agoulnik AI, Lunardon G, Armani A, Bortolanza S, Blaauw B, Sandri M, Foresta C. Protective Role of Testicular Hormone INSL3 From Atrophy and Weakness in Skeletal Muscle. Front Endocrinol (Lausanne) 2018; 9:562. [PMID: 30323788 PMCID: PMC6172310 DOI: 10.3389/fendo.2018.00562] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 09/04/2018] [Indexed: 01/06/2023] Open
Abstract
Androgens are primarily involved in muscle growth, whilst disease-driven muscle wasting is frequently associated with hypogonadism. The Leydig cells of the testes also produce the peptide-hormone Insulin-like peptide 3 (INSL3). INSL3 displays anabolic activity on bone, a target tissue of androgens, and its plasma concentrations are diminished in male hypogonadism. Here we tested the role of INSL3 on muscle mass regulation, in physiological and pathological conditions. Studies on C2C12 cell line showed that INSL3, acting on his specific receptor RXFP2, promotes skeletal muscle protein synthesis through the Akt/mTOR/S6 pathway. Next, studies on Rxfp2 -/- mice showed that INSL3 is required to prevent excessive muscle loss after denervation. Mechanistically, denervated Rxfp2 -/- mice lacked the compensatory activation of the Akt/mTOR/S6 pathway and showed an abnormal ubiquitin-proteasome system activation. Lack of INSL3 activity resulted also in reduced contractile force. These findings underlie a role of INSL3/RXFP2 in protein turnover, contributing to muscle wasting in male hypogonadism.
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Affiliation(s)
- Alberto Ferlin
- Unit of Endocrinology, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Luca De Toni
- Department of Medicine, University of Padova, Padova, Italy
| | - Alexander I. Agoulnik
- Department of Human and Molecular Genetics, Herbert Wertheim College of Medicine, Florida International University, Miami, FL, United States
| | | | - Andrea Armani
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Sergia Bortolanza
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Bert Blaauw
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Marco Sandri
- Department of Biomedical Sciences, University of Padova, Padova, Italy
- Venetian Institute of Molecular Medicine, Padova, Italy
- *Correspondence: Marco Sandri
| | - Carlo Foresta
- Department of Medicine, University of Padova, Padova, Italy
- Carlo Foresta
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27
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Weiland D, Brachvogel B, Hornig-Do HT, Neuhaus JF, Holzer T, Tobin DJ, Niessen CM, Wiesner RJ, Baris OR. Imbalance of Mitochondrial Respiratory Chain Complexes in the Epidermis Induces Severe Skin Inflammation. J Invest Dermatol 2018; 138:132-140. [DOI: 10.1016/j.jid.2017.08.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 08/16/2017] [Accepted: 08/16/2017] [Indexed: 11/24/2022]
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28
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Legati A, Reyes A, Ceccatelli Berti C, Stehling O, Marchet S, Lamperti C, Ferrari A, Robinson AJ, Mühlenhoff U, Lill R, Zeviani M, Goffrini P, Ghezzi D. A novel de novo dominant mutation in ISCU associated with mitochondrial myopathy. J Med Genet 2017; 54:815-824. [PMID: 29079705 PMCID: PMC5740555 DOI: 10.1136/jmedgenet-2017-104822] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 08/16/2017] [Accepted: 08/22/2017] [Indexed: 02/02/2023]
Abstract
BACKGROUND Hereditary myopathy with lactic acidosis and myopathy with deficiency of succinate dehydrogenase and aconitase are variants of a recessive disorder characterised by childhood-onset early fatigue, dyspnoea and palpitations on trivial exercise. The disease is non-progressive, but life-threatening episodes of widespread weakness, metabolic acidosis and rhabdomyolysis may occur. So far, this disease has been molecularly defined only in Swedish patients, all homozygous for a deep intronic splicing affecting mutation in ISCU encoding a scaffold protein for the assembly of iron-sulfur (Fe-S) clusters. A single Scandinavian family was identified with a different mutation, a missense change in compound heterozygosity with the common intronic mutation. The aim of the study was to identify the genetic defect in our proband. METHODS A next-generation sequencing (NGS) approach was carried out on an Italian male who presented in childhood with ptosis, severe muscle weakness and exercise intolerance. His disease was slowly progressive, with partial recovery between episodes. Patient's specimens and yeast models were investigated. RESULTS Histochemical and biochemical analyses on muscle biopsy showed multiple defects affecting mitochondrial respiratory chain complexes. We identified a single heterozygous mutation p.Gly96Val in ISCU, which was absent in DNA from his parents indicating a possible de novo dominant effect in the patient. Patient fibroblasts showed normal levels of ISCU protein and a few variably affected Fe-S cluster-dependent enzymes. Yeast studies confirmed both pathogenicity and dominance of the identified missense mutation. CONCLUSION We describe the first heterozygous dominant mutation in ISCU which results in a phenotype reminiscent of the recessive disease previously reported.
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Affiliation(s)
- Andrea Legati
- Molecular Neurogenetics Unit, Foundation IRCCS Neurological Institute Besta, Milan, Italy
| | - Aurelio Reyes
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Camilla Ceccatelli Berti
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - Oliver Stehling
- Department of Medicine, Institut für Zytobiologie und Zytopathologie, Philipps-Universität, Marburg, Germany
| | - Silvia Marchet
- Molecular Neurogenetics Unit, Foundation IRCCS Neurological Institute Besta, Milan, Italy
| | - Costanza Lamperti
- Molecular Neurogenetics Unit, Foundation IRCCS Neurological Institute Besta, Milan, Italy
| | - Alberto Ferrari
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - Alan J Robinson
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Ulrich Mühlenhoff
- Department of Medicine, Institut für Zytobiologie und Zytopathologie, Philipps-Universität, Marburg, Germany
| | - Roland Lill
- Department of Medicine, Institut für Zytobiologie und Zytopathologie, Philipps-Universität, Marburg, Germany,Unit of Metabolism, LOEWE Zentrum für Synthetische Mikrobiologie SynMikro, Marburg, Germany
| | - Massimo Zeviani
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Paola Goffrini
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - Daniele Ghezzi
- Molecular Neurogenetics Unit, Foundation IRCCS Neurological Institute Besta, Milan, Italy
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Abstract
Mitochondria are intracellular organelles responsible for adenosine triphosphate production. The strict control of intracellular energy needs require proper mitochondrial functioning. The mitochondria are under dual controls of mitochondrial DNA (mtDNA) and nuclear DNA (nDNA). Mitochondrial dysfunction can arise from changes in either mtDNA or nDNA genes regulating function. There are an estimated ∼1500 proteins in the mitoproteome, whereas the mtDNA genome has 37 proteins. There are, to date, ∼275 genes shown to give rise to disease. The unique physiology of mitochondrial functioning contributes to diverse gene expression. The onset and range of phenotypic expression of disease is diverse, with onset from neonatal to seventh decade of life. The range of dysfunction is heterogeneous, ranging from single organ to multisystem involvement. The complexity of disease expression has severely limited gene discovery. Combining phenotypes with improvements in gene sequencing strategies are improving the diagnosis process. This chapter focuses on the interplay of the unique physiology and gene discovery in the current knowledge of genetically derived mitochondrial disease.
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Affiliation(s)
- Russell P Saneto
- Seattle Children's Hospital/University of Washington, Seattle, WA, United States.
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30
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Bottani E, Cerutti R, Harbour ME, Ravaglia S, Dogan SA, Giordano C, Fearnley IM, D'Amati G, Viscomi C, Fernandez-Vizarra E, Zeviani M. TTC19 Plays a Husbandry Role on UQCRFS1 Turnover in the Biogenesis of Mitochondrial Respiratory Complex III. Mol Cell 2017; 67:96-105.e4. [PMID: 28673544 DOI: 10.1016/j.molcel.2017.06.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 04/03/2017] [Accepted: 06/01/2017] [Indexed: 12/29/2022]
Abstract
Loss-of-function mutations in TTC19 (tetra-tricopeptide repeat domain 19) have been associated with severe neurological phenotypes and mitochondrial respiratory chain complex III deficiency. We previously demonstrated the mitochondrial localization of TTC19 and its link with complex III biogenesis. Here we provide detailed insight into the mechanistic role of TTC19, by investigating a Ttc19?/? mouse model that shows progressive neurological and metabolic decline, decreased complex III activity, and increased production of reactive oxygen species. By using both the Ttc19?/? mouse model and a range of human cell lines, we demonstrate that TTC19 binds to the fully assembled complex III dimer, i.e., after the incorporation of the iron-sulfur Rieske protein (UQCRFS1). The in situ maturation of UQCRFS1 produces N-terminal polypeptides, which remain bound to holocomplex III. We show that, in normal conditions, these UQCRFS1 fragments are rapidly removed, but when TTC19 is absent they accumulate within complex III, causing its structural and functional impairment.
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Affiliation(s)
- Emanuela Bottani
- MRC Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building Hills Road, Cambridge CB2 0XY, UK
| | - Raffaele Cerutti
- MRC Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building Hills Road, Cambridge CB2 0XY, UK
| | - Michael E Harbour
- MRC Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building Hills Road, Cambridge CB2 0XY, UK
| | - Sabrina Ravaglia
- Istituto Neurologico "Casimiro Mondino," via Mondino 2, Pavia 27100, Italy
| | - Sukru Anil Dogan
- MRC Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building Hills Road, Cambridge CB2 0XY, UK
| | - Carla Giordano
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, 00161 Rome, Italy
| | - Ian M Fearnley
- MRC Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building Hills Road, Cambridge CB2 0XY, UK
| | - Giulia D'Amati
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, 00161 Rome, Italy
| | - Carlo Viscomi
- MRC Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building Hills Road, Cambridge CB2 0XY, UK
| | - Erika Fernandez-Vizarra
- MRC Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building Hills Road, Cambridge CB2 0XY, UK.
| | - Massimo Zeviani
- MRC Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building Hills Road, Cambridge CB2 0XY, UK.
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31
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Mansueto G, Armani A, Viscomi C, D'Orsi L, De Cegli R, Polishchuk EV, Lamperti C, Di Meo I, Romanello V, Marchet S, Saha PK, Zong H, Blaauw B, Solagna F, Tezze C, Grumati P, Bonaldo P, Pessin JE, Zeviani M, Sandri M, Ballabio A. Transcription Factor EB Controls Metabolic Flexibility during Exercise. Cell Metab 2017; 25:182-196. [PMID: 28011087 PMCID: PMC5241227 DOI: 10.1016/j.cmet.2016.11.003] [Citation(s) in RCA: 213] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 06/24/2016] [Accepted: 11/05/2016] [Indexed: 11/28/2022]
Abstract
The transcription factor EB (TFEB) is an essential component of lysosomal biogenesis and autophagy for the adaptive response to food deprivation. To address the physiological function of TFEB in skeletal muscle, we have used muscle-specific gain- and loss-of-function approaches. Here, we show that TFEB controls metabolic flexibility in muscle during exercise and that this action is independent of peroxisome proliferator-activated receptor-γ coactivator1α (PGC1α). Indeed, TFEB translocates into the myonuclei during physical activity and regulates glucose uptake and glycogen content by controlling expression of glucose transporters, glycolytic enzymes, and pathways related to glucose homeostasis. In addition, TFEB induces the expression of genes involved in mitochondrial biogenesis, fatty acid oxidation, and oxidative phosphorylation. This coordinated action optimizes mitochondrial substrate utilization, thus enhancing ATP production and exercise capacity. These findings identify TFEB as a critical mediator of the beneficial effects of exercise on metabolism.
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Affiliation(s)
- Gelsomina Mansueto
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy
| | - Andrea Armani
- Department of Biomedical Science, University of Padova, Padova 35121, Italy
| | - Carlo Viscomi
- MRC Mitochondrial Biology Unit, Cambridge CB2 0XY, UK; Fondazione IRCCS Istituto Neurologico "C. Besta," 20133 Milan, Italy
| | - Luca D'Orsi
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy
| | - Rossella De Cegli
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy
| | - Elena V Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy
| | - Costanza Lamperti
- Fondazione IRCCS Istituto Neurologico "C. Besta," 20133 Milan, Italy
| | - Ivano Di Meo
- Fondazione IRCCS Istituto Neurologico "C. Besta," 20133 Milan, Italy
| | - Vanina Romanello
- Department of Biomedical Science, University of Padova, Padova 35121, Italy; Venetian Institute of Molecular Medicine, Padova 35129, Italy
| | - Silvia Marchet
- Fondazione IRCCS Istituto Neurologico "C. Besta," 20133 Milan, Italy
| | - Pradip K Saha
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Haihong Zong
- Hepatobiliary, Pancreatic, and Intestinal Research Institute, North Sichuan Medical College, Nanchong, Sichuan 637000, China; Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Bert Blaauw
- Department of Biomedical Science, University of Padova, Padova 35121, Italy
| | - Francesca Solagna
- Department of Biomedical Science, University of Padova, Padova 35121, Italy
| | - Caterina Tezze
- Department of Biomedical Science, University of Padova, Padova 35121, Italy
| | - Paolo Grumati
- Department of Molecular Medicine, University of Padova, Padova 35121, Italy
| | - Paolo Bonaldo
- Department of Molecular Medicine, University of Padova, Padova 35121, Italy
| | - Jeffrey E Pessin
- Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Massimo Zeviani
- MRC Mitochondrial Biology Unit, Cambridge CB2 0XY, UK; Fondazione IRCCS Istituto Neurologico "C. Besta," 20133 Milan, Italy
| | - Marco Sandri
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy; Department of Biomedical Science, University of Padova, Padova 35121, Italy; Venetian Institute of Molecular Medicine, Padova 35129, Italy.
| | - Andrea Ballabio
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Naples, Italy; Medical Genetics, Department of Pediatrics, Federico II University, Via Pansini 5, 80131 Naples, Italy; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA.
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32
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Neuhaus JFG, Baris OR, Kittelmann A, Becker K, Rothschild MA, Wiesner RJ. Catecholamine Metabolism Induces Mitochondrial DNA Deletions and Leads to Severe Adrenal Degeneration during Aging. Neuroendocrinology 2017; 104:72-84. [PMID: 26895241 DOI: 10.1159/000444680] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 02/12/2016] [Indexed: 11/19/2022]
Abstract
BACKGROUND Aging is a multifactorial process characterized by organ loss of function and degeneration, but the mechanisms involved remain elusive. We have shown recently that catecholamine metabolism drives the accumulation of mitochondrial DNA (mtDNA) deletions in dopaminergic cells, which likely contribute to their degeneration during aging. Here we investigated whether the well-documented degeneration and altered function of adrenals during aging is linked to catecholamine production in the medulla followed by accumulation of mtDNA deletions. MATERIAL AND METHODS We analyzed adrenal medullary and cortical samples of both murine and human origin covering a wide range of ages for mtDNA deletion content, mtDNA copy number, mitochondrial and cellular integrity as well as aging-related tissue changes such as fibrosis. RESULTS Indeed, we demonstrate in mice and humans that the adrenal medulla accumulates a strikingly high amount of mtDNA deletions with age, causing mitochondrial dysfunction in the adrenal medulla, but also in the cortex, accompanied by apoptosis and, more importantly, by severe inflammation and remarkable fibrosis. Additionally, a concomitant and dramatic loss of medullary and cortical cells is observed in old animals. CONCLUSION Our results show that accumulation of mtDNA deletions, and the ensuing mitochondrial dysfunction, is a hallmark of adrenal aging, further strengthening the hypothesis that catecholamine metabolism is detrimental to mtDNA integrity, mitochondrial function and cell survival. Moreover, the cell loss potentially induced by mitochondrial dysfunction could explain the decline in adrenal hormonal and steroidal secretion during aging.
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Affiliation(s)
- Johannes Friedrich Georg Neuhaus
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty, University of Cologne, Cologne, Germany
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33
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Zanolini A, Potic A, Carrara F, Lamantea E, Diodato D, Blasevich F, Marchet S, Mora M, Pallotti F, Morandi L, Zeviani M, Lamperti C. Pure myopathy with enlarged mitochondria associated to a new mutation in MTND2 gene. Mol Genet Metab Rep 2016; 10:24-27. [PMID: 28070494 PMCID: PMC5217772 DOI: 10.1016/j.ymgmr.2016.11.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 11/30/2016] [Accepted: 11/30/2016] [Indexed: 11/30/2022] Open
Abstract
To date, only few mutations in the mitochondrial DNA (mtDNA)-encoded ND2 subunit of Complex I have been reported, usually presenting a severe phenotype characterized by early onset encephalomyopathy and early death. In this report, we describe a new mutation in the MTND2 gene in a 21-year-old man with a mild myopathic phenotype characterized by exercise intolerance and increased plasma lactate at rest. Electromyography and brain NMR were normal, and no cardiac involvement was present. Muscle biopsy showed a massive presence of ragged red – COX-positive fibres, with enlarged mitochondria containing osmiophilic inclusions. Biochemical assays revealed a severe isolated complex I deficiency. We identified a novel, heteroplasmic mutation m.4831G > A in the MTND2 gene, causing the p.Gly121Asp substitution in the ND2 protein. The mutation was present in the 95% of mitochondrial genomes from patient's muscle tissue, at a lower level in cells from the urinary tract and at a lowest level in lymphocytes from patient's blood; the base substitution was absent in fibroblasts and in the tissues from proband's healthy mother and brother. The specific skeletal muscle tissue involvement can explain the childhood-onset and the relatively benign, exclusively myopathic course of the disease.
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Affiliation(s)
- Alice Zanolini
- Unit of Molecular Neurogenetics, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', 20126 Milan, Italy
| | - Ana Potic
- Clinic for Child Neurology and Psychiatry, Department of Neurology, Medical Faculty University of Belgrade, Belgrade 11000, Serbia
| | - Franco Carrara
- Unit of Molecular Neurogenetics, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', 20126 Milan, Italy
| | - Eleonora Lamantea
- Unit of Molecular Neurogenetics, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', 20126 Milan, Italy
| | - Daria Diodato
- Unit of Molecular Neurogenetics, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', 20126 Milan, Italy; Division of Neuromuscular and Neurodegenerative Disorders, Ospedale Pediatrico Bambin Gesu, Rome, Italy
| | - Flavia Blasevich
- IV Division of Neurology, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', 20126 Milan, Italy
| | - Silvia Marchet
- Unit of Molecular Neurogenetics, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', 20126 Milan, Italy
| | - Marina Mora
- IV Division of Neurology, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', 20126 Milan, Italy
| | - Francesco Pallotti
- Dept of Surgical and Morphological Sciences, University of Insubria, Varese, Italy
| | - Lucia Morandi
- IV Division of Neurology, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', 20126 Milan, Italy
| | - Massimo Zeviani
- Unit of Molecular Neurogenetics, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', 20126 Milan, Italy; Mitochondrial Biology Unit, Medical Research Council, Cambridge CB2 0XY, UK
| | - Costanza Lamperti
- Unit of Molecular Neurogenetics, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', 20126 Milan, Italy
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34
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Brunetti D, Torsvik J, Dallabona C, Teixeira P, Sztromwasser P, Fernandez-Vizarra E, Cerutti R, Reyes A, Preziuso C, D'Amati G, Baruffini E, Goffrini P, Viscomi C, Ferrero I, Boman H, Telstad W, Johansson S, Glaser E, Knappskog PM, Zeviani M, Bindoff LA. Defective PITRM1 mitochondrial peptidase is associated with Aβ amyloidotic neurodegeneration. EMBO Mol Med 2016; 8:176-90. [PMID: 26697887 PMCID: PMC4772954 DOI: 10.15252/emmm.201505894] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Mitochondrial dysfunction and altered proteostasis are central features of neurodegenerative diseases. The pitrilysin metallopeptidase 1 (PITRM1) is a mitochondrial matrix enzyme, which digests oligopeptides, including the mitochondrial targeting sequences that are cleaved from proteins imported across the inner mitochondrial membrane and the mitochondrial fraction of amyloid beta (Aβ). We identified two siblings carrying a homozygous PITRM1 missense mutation (c.548G>A, p.Arg183Gln) associated with an autosomal recessive, slowly progressive syndrome characterised by mental retardation, spinocerebellar ataxia, cognitive decline and psychosis. The pathogenicity of the mutation was tested in vitro, in mutant fibroblasts and skeletal muscle, and in a yeast model. A Pitrm1+/− heterozygous mouse showed progressive ataxia associated with brain degenerative lesions, including accumulation of Aβ‐positive amyloid deposits. Our results show that PITRM1 is responsible for significant Aβ degradation and that impairment of its activity results in Aβ accumulation, thus providing a mechanistic demonstration of the mitochondrial involvement in amyloidotic neurodegeneration.
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Affiliation(s)
- Dario Brunetti
- MRC Mitochondrial Biology Unit, Wellcome Trust, Cambridge, UK
| | - Janniche Torsvik
- Department of Neurology, Haukeland University Hospital, Bergen, Norway
| | | | - Pedro Teixeira
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Pawel Sztromwasser
- Department of Clinical Science, University of Bergen, Bergen, Norway Computational Biology Unit, Department of Informatics, University of Bergen, Bergen, Norway
| | | | | | - Aurelio Reyes
- MRC Mitochondrial Biology Unit, Wellcome Trust, Cambridge, UK
| | - Carmela Preziuso
- Department of Radiological, Oncological and Pathological Sciences Sapienza University of Rome, Rome, Italy
| | - Giulia D'Amati
- Department of Radiological, Oncological and Pathological Sciences Sapienza University of Rome, Rome, Italy
| | | | - Paola Goffrini
- Department of Life Sciences, University of Parma, Parma, Italy
| | - Carlo Viscomi
- MRC Mitochondrial Biology Unit, Wellcome Trust, Cambridge, UK
| | - Ileana Ferrero
- Department of Life Sciences, University of Parma, Parma, Italy
| | - Helge Boman
- Center for Medical Genetics and Molecular Medicine, Haukeland University Hospital, Bergen, Norway
| | | | - Stefan Johansson
- Department of Clinical Science, University of Bergen, Bergen, Norway Center for Medical Genetics and Molecular Medicine, Haukeland University Hospital, Bergen, Norway
| | - Elzbieta Glaser
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Per M Knappskog
- Department of Clinical Science, University of Bergen, Bergen, Norway Center for Medical Genetics and Molecular Medicine, Haukeland University Hospital, Bergen, Norway
| | - Massimo Zeviani
- MRC Mitochondrial Biology Unit, Wellcome Trust, Cambridge, UK
| | - Laurence A Bindoff
- Department of Neurology, Haukeland University Hospital, Bergen, Norway Department of Clinical Medicine (K1), University of Bergen, Bergen, Norway
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35
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Wang S, Seaberg B, Paez-Colasante X, Rimer M. Defective Acetylcholine Receptor Subunit Switch Precedes Atrophy of Slow-Twitch Skeletal Muscle Fibers Lacking ERK1/2 Kinases in Soleus Muscle. Sci Rep 2016; 6:38745. [PMID: 27934942 PMCID: PMC5146667 DOI: 10.1038/srep38745] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 11/15/2016] [Indexed: 01/10/2023] Open
Abstract
To test the role of extracellular-signal regulated kinases 1 and 2 (ERK1/2) in slow-twitch, type 1 skeletal muscle fibers, we studied the soleus muscle in mice genetically deficient for myofiber ERK1/2. Young adult mutant soleus was drastically wasted, with highly atrophied type 1 fibers, denervation at most synaptic sites, induction of “fetal” acetylcholine receptor gamma subunit (AChRγ), reduction of “adult” AChRε, and impaired mitochondrial biogenesis and function. In weanlings, fiber morphology and mitochondrial markers were mostly normal, yet AChRγ upregulation and AChRε downregulation were observed. Synaptic sites with fetal AChRs in weanling muscle were ~3% in control and ~40% in mutants, with most of the latter on type 1 fibers. These results suggest that: (1) ERK1/2 are critical for slow-twitch fiber growth; (2) a defective γ/ε-AChR subunit switch, preferentially at synapses on slow fibers, precedes wasting of mutant soleus; (3) denervation is likely to drive this wasting, and (4) the neuromuscular synapse is a primary subcellular target for muscle ERK1/2 function in vivo.
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Affiliation(s)
- Shuo Wang
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University Health Science Center, Bryan, Texas, USA
| | - Bonnie Seaberg
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University Health Science Center, Bryan, Texas, USA
| | - Ximena Paez-Colasante
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University Health Science Center, Bryan, Texas, USA
| | - Mendell Rimer
- Department of Neuroscience and Experimental Therapeutics, Texas A&M University Health Science Center, Bryan, Texas, USA
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36
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Alston CL, Rocha MC, Lax NZ, Turnbull DM, Taylor RW. The genetics and pathology of mitochondrial disease. J Pathol 2016; 241:236-250. [PMID: 27659608 PMCID: PMC5215404 DOI: 10.1002/path.4809] [Citation(s) in RCA: 263] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 09/15/2016] [Accepted: 09/16/2016] [Indexed: 12/30/2022]
Abstract
Mitochondria are double-membrane-bound organelles that are present in all nucleated eukaryotic cells and are responsible for the production of cellular energy in the form of ATP. Mitochondrial function is under dual genetic control - the 16.6-kb mitochondrial genome, with only 37 genes, and the nuclear genome, which encodes the remaining ∼1300 proteins of the mitoproteome. Mitochondrial dysfunction can arise because of defects in either mitochondrial DNA or nuclear mitochondrial genes, and can present in childhood or adulthood in association with vast clinical heterogeneity, with symptoms affecting a single organ or tissue, or multisystem involvement. There is no cure for mitochondrial disease for the vast majority of mitochondrial disease patients, and a genetic diagnosis is therefore crucial for genetic counselling and recurrence risk calculation, and can impact on the clinical management of affected patients. Next-generation sequencing strategies are proving pivotal in the discovery of new disease genes and the diagnosis of clinically affected patients; mutations in >250 genes have now been shown to cause mitochondrial disease, and the biochemical, histochemical, immunocytochemical and neuropathological characterization of these patients has led to improved diagnostic testing strategies and novel diagnostic techniques. This review focuses on the current genetic landscape associated with mitochondrial disease, before focusing on advances in studying associated mitochondrial pathology in two, clinically relevant organs - skeletal muscle and brain. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Charlotte L Alston
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Mariana C Rocha
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Nichola Z Lax
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Doug M Turnbull
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Robert W Taylor
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, UK
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37
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Peralta S, Garcia S, Yin HY, Arguello T, Diaz F, Moraes CT. Sustained AMPK activation improves muscle function in a mitochondrial myopathy mouse model by promoting muscle fiber regeneration. Hum Mol Genet 2016; 25:3178-3191. [PMID: 27288451 PMCID: PMC5179920 DOI: 10.1093/hmg/ddw167] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 04/22/2016] [Accepted: 05/23/2016] [Indexed: 12/25/2022] Open
Abstract
Acute pharmacological activation of adenosine monophosphate (AMP)-kinase using 5-aminoimidazole-4-carboxamide-1-b-D-ribofuranoside (AICAR) has been shown to improve muscle mitochondrial function by increasing mitochondrial biogenesis. We asked whether prolonged AICAR treatment is beneficial in a mouse model of slowly progressing mitochondrial myopathy (Cox10-Mef2c-Cre), and whether the compensatory mechanism is indeed an increase in mitochondrial biogenesis. We treated the animals for 3 months and found that sustained AMP-dependent kinase activation improved cytochrome c oxidase activity, rescued the motor phenotype and delayed the onset of the myopathy. This improvement was observed whether treatment started before or after the onset of the disease. We found that AICAR increased skeletal muscle regeneration thereby decreasing the levels of deleted Cox10-floxed alleles. We conclude that although increase in mitochondrial biogenesis and other pathways may contribute, the main mechanism by which AICAR improves the myopathy phenotype is by promoting muscle regeneration.
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Affiliation(s)
| | | | | | | | | | - Carlos T Moraes
- Department of Neurology
- Genetics Graduate Program
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
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38
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Konokhova Y, Spendiff S, Jagoe RT, Aare S, Kapchinsky S, MacMillan NJ, Rozakis P, Picard M, Aubertin-Leheudre M, Pion CH, Bourbeau J, Hepple RT, Taivassalo T. Failed upregulation of TFAM protein and mitochondrial DNA in oxidatively deficient fibers of chronic obstructive pulmonary disease locomotor muscle. Skelet Muscle 2016; 6:10. [PMID: 26893822 PMCID: PMC4758107 DOI: 10.1186/s13395-016-0083-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 02/06/2016] [Indexed: 12/29/2023] Open
Abstract
Background Low mitochondrial content and oxidative capacity are well-established features of locomotor muscle dysfunction, a prevalent and debilitating systemic occurrence in patients with chronic obstructive pulmonary disease (COPD). Although the exact cause is not firmly established, physical inactivity and oxidative stress are among the proposed underlying mechanisms. Here, we assess the impact of COPD pathophysiology on mitochondrial DNA (mtDNA) integrity, biogenesis, and cellular oxidative capacity in locomotor muscle of COPD patients and healthy controls. We hypothesized that the high oxidative stress environment of COPD muscle would yield a higher presence of deletion-containing mtDNA and oxidative-deficient fibers and impaired capacity for mitochondrial biogenesis. Methods Vastus lateralis biopsies were analyzed from 29 COPD patients and 19 healthy age-matched controls for the presence of mtDNA deletions, levels of oxidatively damaged DNA, mtDNA copy number, and regulators of mitochondrial biogenesis as well the proportion of oxidative-deficient fibers (detected histologically as cytochrome c oxidase-deficient, succinate dehydrogenase positive (COX−/SDH+ )). Additionally, mtDNA copy number and mitochondrial transcription factor A (TFAM) content were measured in laser captured COX−SDH+ and normal single fibers of both COPD and controls. Results Compared to controls, COPD muscle exhibited significantly higher levels of oxidatively damaged DNA (8-hydroxy-2-deoxyguanosine (8-OHdG) levels = 387 ± 41 vs. 258 ± 21 pg/mL) and higher prevalence of mtDNA deletions (74 vs. 15 % of subjects in each group), which was accompanied by a higher abundance of oxidative-deficient fibers (8.0 ± 2.1 vs. 1.5 ± 0.4 %). Interestingly, COPD patients with mtDNA deletions had higher levels of 8-OHdG (457 ± 46 pg/mL) and longer smoking history (66.3 ± 7.5 years) than patients without deletions (197 ± 29 pg/mL; 38.0 ± 7.3 years). Transcript levels of regulators of mitochondrial biogenesis and oxidative metabolism were upregulated in COPD compared to controls. However, single fiber analyses of COX−/SDH+ and normal fibers exposed an impairment in mitochondrial biogenesis in COPD; in healthy controls, we detected a marked upregulation of mtDNA copy number and TFAM protein in COX−/SDH+ compared to normal fibers, reflecting the expected compensatory attempt by the oxidative-deficient cells to increase energy levels; in contrast, they were similar between COX−/SDH+ and normal fibers in COPD patients. Taken together, these findings suggest that although the signaling factors regulating mitochondrial biogenesis are increased in COPD muscle, impairment in the translation of these signals prevents the restoration of normal oxidative capacity. Conclusions Single fiber analyses provide the first substantive evidence that low muscle oxidative capacity in COPD cannot be explained by physical inactivity alone and is likely driven by the disease pathophysiology.
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Affiliation(s)
- Yana Konokhova
- Department of Kinesiology, McGill University, 475 Pine Ave West, Room 222, Montreal, Quebec H2W1S4 Canada.,Department of Critical Care Medicine, McGill University Health Center, Montreal, Canada
| | - Sally Spendiff
- Department of Kinesiology, McGill University, 475 Pine Ave West, Room 222, Montreal, Quebec H2W1S4 Canada.,Department of Critical Care Medicine, McGill University Health Center, Montreal, Canada
| | - R Thomas Jagoe
- Departments of Oncology and Medicine, McGill University, Montreal, Canada
| | - Sudhakar Aare
- Department of Critical Care Medicine, McGill University Health Center, Montreal, Canada
| | - Sophia Kapchinsky
- Department of Kinesiology, McGill University, 475 Pine Ave West, Room 222, Montreal, Quebec H2W1S4 Canada
| | - Norah J MacMillan
- Department of Kinesiology, McGill University, 475 Pine Ave West, Room 222, Montreal, Quebec H2W1S4 Canada
| | - Paul Rozakis
- Department of Kinesiology, McGill University, 475 Pine Ave West, Room 222, Montreal, Quebec H2W1S4 Canada
| | - Martin Picard
- Division of Behavioral Medicine, Department of Psychiatry, Department of Neurology, and Columbia Translational Neuroscience Initiative, Columbia University College of Physicians and Surgeons, Columbia University Medical Center, New York, NY USA
| | | | - Charlotte H Pion
- Département de Kinanthropologie, Université du Québec à Montréal, Montreal, Canada
| | - Jean Bourbeau
- Respiratory Epidemiology and Clinical Research Unit, Center for Innovative Medicine (CIM), McGill University Health Centre, Montreal, Canada
| | - Russell T Hepple
- Department of Kinesiology, McGill University, 475 Pine Ave West, Room 222, Montreal, Quebec H2W1S4 Canada.,Department of Critical Care Medicine, McGill University Health Center, Montreal, Canada.,Meakins Christie Laboratories, McGill University, Montreal, Canada
| | - Tanja Taivassalo
- Department of Kinesiology, McGill University, 475 Pine Ave West, Room 222, Montreal, Quebec H2W1S4 Canada.,Respiratory Epidemiology and Clinical Research Unit, Center for Innovative Medicine (CIM), McGill University Health Centre, Montreal, Canada
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Rocha MC, Grady JP, Grünewald A, Vincent A, Dobson PF, Taylor RW, Turnbull DM, Rygiel KA. A novel immunofluorescent assay to investigate oxidative phosphorylation deficiency in mitochondrial myopathy: understanding mechanisms and improving diagnosis. Sci Rep 2015; 5:15037. [PMID: 26469001 PMCID: PMC4606788 DOI: 10.1038/srep15037] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 09/04/2015] [Indexed: 02/07/2023] Open
Abstract
Oxidative phosphorylation defects in human tissues are often challenging to quantify due to a mosaic pattern of deficiency. Biochemical assays are difficult to interpret due to the varying enzyme deficiency levels found in individual cells. Histochemical analysis allows semi-quantitative assessment of complex II and complex IV activities, but there is no validated histochemical assay to assess complex I activity which is frequently affected in mitochondrial pathology. To help improve the diagnosis of mitochondrial disease and to study the mechanisms underlying mitochondrial abnormalities in disease, we have developed a quadruple immunofluorescent technique enabling the quantification of key respiratory chain subunits of complexes I and IV, together with an indicator of mitochondrial mass and a cell membrane marker. This assay gives precise and objective quantification of protein abundance in large numbers of individual muscle fibres. By assessing muscle biopsies from subjects with a range of different mitochondrial genetic defects we have demonstrated that specific genotypes exhibit distinct biochemical signatures in muscle, providing evidence for the diagnostic use of the technique, as well as insight into the underlying molecular pathology. Stringent testing for reproducibility and sensitivity confirms the potential value of the technique for mechanistic studies of disease and in the evaluation of therapeutic approaches.
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Affiliation(s)
- Mariana C Rocha
- Newcastle University Centre for Ageing and Vitality, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom.,Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - John P Grady
- Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Anne Grünewald
- Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Amy Vincent
- Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Philip F Dobson
- Newcastle University Centre for Ageing and Vitality, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Robert W Taylor
- Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Doug M Turnbull
- Newcastle University Centre for Ageing and Vitality, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom.,Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Karolina A Rygiel
- Newcastle University Centre for Ageing and Vitality, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom.,Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, United Kingdom
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40
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Varanita T, Soriano ME, Romanello V, Zaglia T, Quintana-Cabrera R, Semenzato M, Menabò R, Costa V, Civiletto G, Pesce P, Viscomi C, Zeviani M, Di Lisa F, Mongillo M, Sandri M, Scorrano L. The OPA1-dependent mitochondrial cristae remodeling pathway controls atrophic, apoptotic, and ischemic tissue damage. Cell Metab 2015; 21:834-44. [PMID: 26039448 PMCID: PMC4457892 DOI: 10.1016/j.cmet.2015.05.007] [Citation(s) in RCA: 326] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 02/18/2015] [Accepted: 05/04/2015] [Indexed: 01/07/2023]
Abstract
Mitochondrial morphological and ultrastructural changes occur during apoptosis and autophagy, but whether they are relevant in vivo for tissue response to damage is unclear. Here we investigate the role of the optic atrophy 1 (OPA1)-dependent cristae remodeling pathway in vivo and provide evidence that it regulates the response of multiple tissues to apoptotic, necrotic, and atrophic stimuli. Genetic inhibition of the cristae remodeling pathway in vivo does not affect development, but protects mice from denervation-induced muscular atrophy, ischemic heart and brain damage, as well as hepatocellular apoptosis. Mechanistically, OPA1-dependent mitochondrial cristae stabilization increases mitochondrial respiratory efficiency and blunts mitochondrial dysfunction, cytochrome c release, and reactive oxygen species production. Our results indicate that the OPA1-dependent cristae remodeling pathway is a fundamental, targetable determinant of tissue damage in vivo.
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Affiliation(s)
- Tatiana Varanita
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy; Department of Biology, University of Padova, Via C. Colombo 3, 35121 Padova, Italy
| | - Maria Eugenia Soriano
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy; Department of Biology, University of Padova, Via C. Colombo 3, 35121 Padova, Italy
| | - Vanina Romanello
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy; Department of Biomedical Sciences, University of Padova, Via C. Colombo 3, 35121 Padova, Italy
| | - Tania Zaglia
- Department of Biomedical Sciences, University of Padova, Via C. Colombo 3, 35121 Padova, Italy
| | - Rubén Quintana-Cabrera
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy; Department of Biology, University of Padova, Via C. Colombo 3, 35121 Padova, Italy
| | - Martina Semenzato
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy; Department of Biology, University of Padova, Via C. Colombo 3, 35121 Padova, Italy
| | - Roberta Menabò
- Institute of Neuroscience, National Research Council of Italy (CNR), Via C. Colombo 3, 35121 Padova, Italy
| | - Veronica Costa
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy
| | - Gabriele Civiletto
- Fondazione IRCCS Istituto Neurologico "C. Besta," Via L. Temolo 4, 20126 Milan, Italy; MRC Mitochondrial Biology Unit, MRC Building, Hills Road, Cambridge CB2 0XY, UK
| | - Paola Pesce
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Via Giustiniani, 2, 35128 Padova, Italy
| | - Carlo Viscomi
- Fondazione IRCCS Istituto Neurologico "C. Besta," Via L. Temolo 4, 20126 Milan, Italy; MRC Mitochondrial Biology Unit, MRC Building, Hills Road, Cambridge CB2 0XY, UK
| | - Massimo Zeviani
- Fondazione IRCCS Istituto Neurologico "C. Besta," Via L. Temolo 4, 20126 Milan, Italy; MRC Mitochondrial Biology Unit, MRC Building, Hills Road, Cambridge CB2 0XY, UK
| | - Fabio Di Lisa
- Department of Biomedical Sciences, University of Padova, Via C. Colombo 3, 35121 Padova, Italy
| | - Marco Mongillo
- Department of Biomedical Sciences, University of Padova, Via C. Colombo 3, 35121 Padova, Italy
| | - Marco Sandri
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy; Department of Biomedical Sciences, University of Padova, Via C. Colombo 3, 35121 Padova, Italy
| | - Luca Scorrano
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, Via Orus 2, 35129 Padova, Italy; Department of Biology, University of Padova, Via C. Colombo 3, 35121 Padova, Italy.
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Opa1 overexpression ameliorates the phenotype of two mitochondrial disease mouse models. Cell Metab 2015; 21:845-54. [PMID: 26039449 PMCID: PMC4457891 DOI: 10.1016/j.cmet.2015.04.016] [Citation(s) in RCA: 165] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 02/13/2015] [Accepted: 04/12/2015] [Indexed: 02/07/2023]
Abstract
Increased levels of the mitochondria-shaping protein Opa1 improve respiratory chain efficiency and protect from tissue damage, suggesting that it could be an attractive target to counteract mitochondrial dysfunction. Here we show that Opa1 overexpression ameliorates two mouse models of defective mitochondrial bioenergetics. The offspring from crosses of a constitutive knockout for the structural complex I component Ndufs4 (Ndufs4(-/-)), and of a muscle-specific conditional knockout for the complex IV assembly factor Cox15 (Cox15(sm/sm)), with Opa1 transgenic (Opa1(tg)) mice showed improved motor skills and respiratory chain activities compared to the naive, non-Opa1-overexpressing, models. While the amelioration was modest in Ndufs4(-/-)::Opa1(tg) mice, correction of cristae ultrastructure and mitochondrial respiration, improvement of motor performance and prolongation of lifespan were remarkable in Cox15(sm/sm)::Opa1(tg) mice. Mechanistically, respiratory chain supercomplexes were increased in Cox15(sm/sm)::Opa1(tg) mice, and residual monomeric complex IV was stabilized. In conclusion, cristae shape amelioration by controlled Opa1 overexpression improves two mouse models of mitochondrial disease.
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Mosaic Deficiency in Mitochondrial Oxidative Metabolism Promotes Cardiac Arrhythmia during Aging. Cell Metab 2015; 21:667-77. [PMID: 25955204 DOI: 10.1016/j.cmet.2015.04.005] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Revised: 02/04/2015] [Accepted: 03/31/2015] [Indexed: 11/21/2022]
Abstract
Aging is a progressive decline of body function, during which many tissues accumulate few cells with high levels of deleted mitochondrial DNA (mtDNA), leading to a defect of mitochondrial functions. Whether this mosaic mitochondrial deficiency contributes to organ dysfunction is unknown. To investigate this, we generated mice with an accelerated accumulation of mtDNA deletions in the myocardium, by expressing a dominant-negative mutant mitochondrial helicase. These animals accumulated few randomly distributed cardiomyocytes with compromised mitochondrial function, which led to spontaneous ventricular premature contractions and AV blocks at 18 months. These symptoms were not caused by a general mitochondrial dysfunction in the entire myocardium, and were not observed in mice at 12 months with significantly lower numbers of dysfunctional cells. Therefore, our results suggest that the disposition to arrhythmia typically found in the aged human heart might be due to the random accumulation of mtDNA deletions and the subsequent mosaic respiratory chain deficiency.
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"Myo-cardiomyopathy" is commonly associated with the A8344G "MERRF" mutation. J Neurol 2015; 262:701-10. [PMID: 25559684 DOI: 10.1007/s00415-014-7632-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 12/22/2014] [Accepted: 12/24/2014] [Indexed: 10/24/2022]
Abstract
The objective of the study was to better characterize the clinical phenotype associated with the A8344G "MERRF" mutation of mitochondrial DNA. Fifteen mutated patients were extensively investigated. The frequency of main clinical features was: exercise intolerance and/or muscle weakness 67 %, respiratory involvement 67 %, lactic acidosis 67 %, cardiac abnormalities 53 %, peripheral neuropathy 47 %, myoclonus 40 %, epilepsy 40 %, ataxia 13 %. A restrictive respiratory insufficiency requiring ventilatory support was observed in about half of our patients. One patient developed a severe and rapidly progressive cardiomyopathy requiring cardioverter-defibrillator implantation. Five patients died of overwhelming, intractable lactic acidosis. Serial muscle MRIs identified a consistent pattern of muscle involvement and progression. Cardiac MRI showed non-ischemic late gadolinium enhancement in the left ventricle inferolateral part as early sign of myocardial involvement. Brain spectroscopy demonstrated increased peak of choline and reduction of N-acetylaspartate. Lactate was never detected in brain areas, while it could be documented in ventricles. We confirm that muscle involvement is the most frequent clinical feature associated with A8443G mutation. In contrast with previous reports, however, about half of our patients did not develop signs of CNS involvement even in later stages of the disease. The difference may be related to the infrequent investigation of A8344G mutation in 'pure' mitochondrial myo-cardiomyopathy, representing a bias and a possible cause of syndrome's underestimation. Our study highlights the importance of lactic acidosis and respiratory muscle insufficiency as critical prognostic factors. Muscle and cardiac MRI and brain spectroscopy may be useful tools in diagnosis and follow-up of MERRF.
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44
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Melchionda L, Haack TB, Hardy S, Abbink TEM, Fernandez-Vizarra E, Lamantea E, Marchet S, Morandi L, Moggio M, Carrozzo R, Torraco A, Diodato D, Strom TM, Meitinger T, Tekturk P, Yapici Z, Al-Murshedi F, Stevens R, Rodenburg RJ, Lamperti C, Ardissone A, Moroni I, Uziel G, Prokisch H, Taylor RW, Bertini E, van der Knaap MS, Ghezzi D, Zeviani M. Mutations in APOPT1, encoding a mitochondrial protein, cause cavitating leukoencephalopathy with cytochrome c oxidase deficiency. Am J Hum Genet 2014; 95:315-25. [PMID: 25175347 PMCID: PMC4157140 DOI: 10.1016/j.ajhg.2014.08.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 08/08/2014] [Indexed: 11/17/2022] Open
Abstract
Cytochrome c oxidase (COX) deficiency is a frequent biochemical abnormality in mitochondrial disorders, but a large fraction of cases remains genetically undetermined. Whole-exome sequencing led to the identification of APOPT1 mutations in two Italian sisters and in a third Turkish individual presenting severe COX deficiency. All three subjects presented a distinctive brain MRI pattern characterized by cavitating leukodystrophy, predominantly in the posterior region of the cerebral hemispheres. We then found APOPT1 mutations in three additional unrelated children, selected on the basis of these particular MRI features. All identified mutations predicted the synthesis of severely damaged protein variants. The clinical features of the six subjects varied widely from acute neurometabolic decompensation in late infancy to subtle neurological signs, which appeared in adolescence; all presented a chronic, long-surviving clinical course. We showed that APOPT1 is targeted to and localized within mitochondria by an N-terminal mitochondrial targeting sequence that is eventually cleaved off from the mature protein. We then showed that APOPT1 is virtually absent in fibroblasts cultured in standard conditions, but its levels increase by inhibiting the proteasome or after oxidative challenge. Mutant fibroblasts showed reduced amount of COX holocomplex and higher levels of reactive oxygen species, which both shifted toward control values by expressing a recombinant, wild-type APOPT1 cDNA. The shRNA-mediated knockdown of APOPT1 in myoblasts and fibroblasts caused dramatic decrease in cell viability. APOPT1 mutations are responsible for infantile or childhood-onset mitochondrial disease, hallmarked by the combination of profound COX deficiency with a distinctive neuroimaging presentation.
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Affiliation(s)
- Laura Melchionda
- Unit of Molecular Neurogenetics, Foundation IRCCS Institute of Neurology Besta, 20126 Milan, Italy
| | - Tobias B Haack
- Institute of Human Genetics, Technische Universität München, Munich 81675, Germany; Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg 85764, Germany
| | - Steven Hardy
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Truus E M Abbink
- Departments of Child Neurology and Functional Genomics, Neuroscience Campus Amsterdam, VU University and VU University Medical Center, Amsterdam 1081 HV, the Netherlands
| | | | - Eleonora Lamantea
- Unit of Molecular Neurogenetics, Foundation IRCCS Institute of Neurology Besta, 20126 Milan, Italy
| | - Silvia Marchet
- Unit of Molecular Neurogenetics, Foundation IRCCS Institute of Neurology Besta, 20126 Milan, Italy
| | - Lucia Morandi
- Neuromuscular Diseases and Neuroimmunology Unit, Foundation IRCCS Institute of Neurology Besta, 20133 Milan, Italy
| | - Maurizio Moggio
- Neuromuscular Unit, Department of Neurology, Centro Dino Ferrari, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, 20122 Milan, Italy
| | - Rosalba Carrozzo
- Unit of Neuromuscular Disorders, Laboratory of Molecular Medicine, Bambino Gesu' Children's Research Hospital, 00165 Rome, Italy
| | - Alessandra Torraco
- Unit of Neuromuscular Disorders, Laboratory of Molecular Medicine, Bambino Gesu' Children's Research Hospital, 00165 Rome, Italy
| | - Daria Diodato
- Unit of Molecular Neurogenetics, Foundation IRCCS Institute of Neurology Besta, 20126 Milan, Italy; Unit of Neuromuscular Disorders, Laboratory of Molecular Medicine, Bambino Gesu' Children's Research Hospital, 00165 Rome, Italy
| | - Tim M Strom
- Institute of Human Genetics, Technische Universität München, Munich 81675, Germany; Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg 85764, Germany
| | - Thomas Meitinger
- Institute of Human Genetics, Technische Universität München, Munich 81675, Germany; Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg 85764, Germany
| | - Pinar Tekturk
- Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, 34098 Istanbul, Turkey
| | - Zuhal Yapici
- Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, 34098 Istanbul, Turkey
| | - Fathiya Al-Murshedi
- Genetic and Developmental Medicine Clinic, Sultan Qaboos University Hospital, Muscat 123, Oman
| | - René Stevens
- Department of Paediatrics, CHC Clinique de l'Espérance at Liège, Liège 4000, Belgium
| | - Richard J Rodenburg
- Nijmegen Center for Mitochondrial Disorders, Laboratory for Genetic, Endocrine, and Metabolic Disorders, Department of Pediatrics, Radboud University Medical Center, 9101 Nijmegen, the Netherlands
| | - Costanza Lamperti
- Unit of Molecular Neurogenetics, Foundation IRCCS Institute of Neurology Besta, 20126 Milan, Italy
| | - Anna Ardissone
- Department of Child Neurology, Foundation IRCCS Institute of Neurology Besta, 20133 Milan, Italy
| | - Isabella Moroni
- Department of Child Neurology, Foundation IRCCS Institute of Neurology Besta, 20133 Milan, Italy
| | - Graziella Uziel
- Department of Child Neurology, Foundation IRCCS Institute of Neurology Besta, 20133 Milan, Italy
| | - Holger Prokisch
- Institute of Human Genetics, Technische Universität München, Munich 81675, Germany; Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg 85764, Germany
| | - Robert W Taylor
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Enrico Bertini
- Unit of Neuromuscular Disorders, Laboratory of Molecular Medicine, Bambino Gesu' Children's Research Hospital, 00165 Rome, Italy
| | - Marjo S van der Knaap
- Departments of Child Neurology and Functional Genomics, Neuroscience Campus Amsterdam, VU University and VU University Medical Center, Amsterdam 1081 HV, the Netherlands
| | - Daniele Ghezzi
- Unit of Molecular Neurogenetics, Foundation IRCCS Institute of Neurology Besta, 20126 Milan, Italy.
| | - Massimo Zeviani
- Unit of Molecular Neurogenetics, Foundation IRCCS Institute of Neurology Besta, 20126 Milan, Italy; MRC Mitochondrial Biology Unit, Cambridge CB2 0XY, UK.
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Kukat A, Dogan SA, Edgar D, Mourier A, Jacoby C, Maiti P, Mauer J, Becker C, Senft K, Wibom R, Kudin AP, Hultenby K, Flögel U, Rosenkranz S, Ricquier D, Kunz WS, Trifunovic A. Loss of UCP2 attenuates mitochondrial dysfunction without altering ROS production and uncoupling activity. PLoS Genet 2014; 10:e1004385. [PMID: 24945157 PMCID: PMC4063685 DOI: 10.1371/journal.pgen.1004385] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 04/02/2014] [Indexed: 11/18/2022] Open
Abstract
Although mitochondrial dysfunction is often accompanied by excessive reactive oxygen species (ROS) production, we previously showed that an increase in random somatic mtDNA mutations does not result in increased oxidative stress. Normal levels of ROS and oxidative stress could also be a result of an active compensatory mechanism such as a mild increase in proton leak. Uncoupling protein 2 (UCP2) was proposed to play such a role in many physiological situations. However, we show that upregulation of UCP2 in mtDNA mutator mice is not associated with altered proton leak kinetics or ROS production, challenging the current view on the role of UCP2 in energy metabolism. Instead, our results argue that high UCP2 levels allow better utilization of fatty acid oxidation resulting in a beneficial effect on mitochondrial function in heart, postponing systemic lactic acidosis and resulting in longer lifespan in these mice. This study proposes a novel mechanism for an adaptive response to mitochondrial cardiomyopathy that links changes in metabolism to amelioration of respiratory chain deficiency and longer lifespan.
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Affiliation(s)
- Alexandra Kukat
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, Cologne, Germany
- Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Sukru Anil Dogan
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, Cologne, Germany
| | - Daniel Edgar
- Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Arnaud Mourier
- Max Planck Institute for Biology of Aging, Cologne, Germany
| | - Christoph Jacoby
- Department of Cardiovascular Physiology, Heinrich-Heine-University, Düsseldorf, Germany
| | - Priyanka Maiti
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, Cologne, Germany
| | - Jan Mauer
- Max Planck Institute for Neurological Research, Cologne, Germany
| | - Christina Becker
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, Cologne, Germany
| | - Katharina Senft
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, Cologne, Germany
| | - Rolf Wibom
- Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Alexei P. Kudin
- Department of Epileptology, University of Bonn, Bonn, Germany
| | - Kjell Hultenby
- Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Ulrich Flögel
- Department of Cardiovascular Physiology, Heinrich-Heine-University, Düsseldorf, Germany
| | - Stephan Rosenkranz
- Department III of Internal Medicine, University of Cologne, Cologne, Germany
- Cologne Cardiovascular Research Center (CCRC) and Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Daniel Ricquier
- University Paris Descartes, Faculty of Medicine, CNRS FRE3210, Paris, France
| | - Wolfram S. Kunz
- Department of Epileptology, University of Bonn, Bonn, Germany
| | - Aleksandra Trifunovic
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, Cologne, Germany
- Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
- Cologne Cardiovascular Research Center (CCRC) and Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
- * E-mail:
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Cerutti R, Pirinen E, Lamperti C, Marchet S, Sauve AA, Li W, Leoni V, Schon EA, Dantzer F, Auwerx J, Viscomi C, Zeviani M. NAD(+)-dependent activation of Sirt1 corrects the phenotype in a mouse model of mitochondrial disease. Cell Metab 2014; 19:1042-9. [PMID: 24814483 PMCID: PMC4051987 DOI: 10.1016/j.cmet.2014.04.001] [Citation(s) in RCA: 220] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 01/17/2014] [Accepted: 03/14/2014] [Indexed: 01/22/2023]
Abstract
Mitochondrial disorders are highly heterogeneous conditions characterized by defects of the mitochondrial respiratory chain. Pharmacological activation of mitochondrial biogenesis has been proposed as an effective means to correct the biochemical defects and ameliorate the clinical phenotype in these severely disabling, often fatal, disorders. Pathways related to mitochondrial biogenesis are targets of Sirtuin1, a NAD(+)-dependent protein deacetylase. As NAD(+) boosts the activity of Sirtuin1 and other sirtuins, intracellular levels of NAD(+) play a key role in the homeostatic control of mitochondrial function by the metabolic status of the cell. We show here that supplementation with nicotinamide riboside, a natural NAD(+) precursor, or reduction of NAD(+) consumption by inhibiting the poly(ADP-ribose) polymerases, leads to marked improvement of the respiratory chain defect and exercise intolerance of the Sco2 knockout/knockin mouse, a mitochondrial disease model characterized by impaired cytochrome c oxidase biogenesis. This strategy is potentially translatable into therapy of mitochondrial disorders in humans.
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Affiliation(s)
- Raffaele Cerutti
- Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, 20133 Milan, Italy; MRC-Mitochondrial Biology Unit, Cambridge CB2 0XY, UK
| | - Eija Pirinen
- Laboratory for Integrative and Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland; Biotechnology and Molecular Medicine, A.I. Virtanen Institute for Molecular Sciences, Biocenter Kuopio, University of Eastern Finland, FI-70211 Kuopio, Finland
| | - Costanza Lamperti
- Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, 20133 Milan, Italy
| | - Silvia Marchet
- Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, 20133 Milan, Italy
| | - Anthony A Sauve
- Department of Pharmacology, Weill Cornell Medical College, New York, NY 10021, USA
| | - Wei Li
- Department of Pharmacology, Weill Cornell Medical College, New York, NY 10021, USA
| | - Valerio Leoni
- Laboratory of Clinical Pathology and Medical Genetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, 20133 Milan, Italy
| | - Eric A Schon
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Françoise Dantzer
- Biotechnologie et Signalisation Cellulaire, UMR7242 CNRS, Université de Strasbourg, ESBS, 67412 Illkirch, France
| | - Johan Auwerx
- Laboratory for Integrative and Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
| | - Carlo Viscomi
- Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, 20133 Milan, Italy; MRC-Mitochondrial Biology Unit, Cambridge CB2 0XY, UK.
| | - Massimo Zeviani
- Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, 20133 Milan, Italy; MRC-Mitochondrial Biology Unit, Cambridge CB2 0XY, UK.
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47
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Namba T, Takabatake Y, Kimura T, Takahashi A, Yamamoto T, Matsuda J, Kitamura H, Niimura F, Matsusaka T, Iwatani H, Matsui I, Kaimori J, Kioka H, Isaka Y, Rakugi H. Autophagic clearance of mitochondria in the kidney copes with metabolic acidosis. J Am Soc Nephrol 2014; 25:2254-66. [PMID: 24700866 DOI: 10.1681/asn.2013090986] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Metabolic acidosis, a common complication of CKD, causes mitochondrial stress by undefined mechanisms. Selective autophagy of impaired mitochondria, called mitophagy, contributes toward maintaining cellular homeostasis in various settings. We hypothesized that mitophagy is involved in proximal tubular cell adaptations to chronic metabolic acidosis. In transgenic mice expressing green fluorescent protein-tagged microtubule-associated protein 1 light chain 3 (GFP-LC3), NH4Cl loading increased the number of GFP puncta exclusively in the proximal tubule. In vitro, culture in acidic medium produced similar results in proximal tubular cell lines stably expressing GFP-LC3 and facilitated the degradation of SQSTM1/p62 in wild-type cells, indicating enhanced autophagic flux. Upon acid loading, proximal tubule-specific autophagy-deficient (Atg5-deficient) mice displayed significantly reduced ammonium production and severe metabolic acidosis compared with wild-type mice. In vitro and in vivo, acid loading caused Atg5-deficient proximal tubular cells to exhibit reduced mitochondrial respiratory chain activity, reduced mitochondrial membrane potential, and fragmented morphology with marked swelling in mitochondria. GFP-LC3-tagged autophagosomes colocalized with ubiquitinated mitochondria in proximal tubular cells cultured in acidic medium, suggesting that metabolic acidosis induces mitophagy. Furthermore, restoration of Atg5-intact nuclei in Atg5-deficient proximal tubular cells increased mitochondrial membrane potential and ammoniagenesis. In conclusion, metabolic acidosis induces autophagy in proximal tubular cells, which is indispensable for maintaining proper mitochondrial functions including ammoniagenesis, and thus for adapted urinary acid excretion. Our results provide a rationale for the beneficial effect of alkali supplementation in CKD, a condition in which autophagy may be reduced, and suggest a new therapeutic option for acidosis by modulating autophagy.
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Affiliation(s)
- Tomoko Namba
- Departments of Geriatric Medicine and Nephrology (B6)
| | | | - Tomonori Kimura
- Departments of Geriatric Medicine and Nephrology (B6), Department of Molecular Genetics and Microbiology, University of New Mexico, Albuquerque, New Mexico; and
| | | | | | - Jun Matsuda
- Departments of Geriatric Medicine and Nephrology (B6)
| | | | | | - Taiji Matsusaka
- Institute of Medical Science and Department of Internal Medicine, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | | | - Isao Matsui
- Departments of Geriatric Medicine and Nephrology (B6)
| | | | - Hidetaka Kioka
- Medical Biochemistry, and Cardiovascular Medicine, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | | | - Hiromi Rakugi
- Departments of Geriatric Medicine and Nephrology (B6)
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48
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Fujioka H, Tandler B, Cohen M, Koontz D, Hoppel CL. Multiple mitochondrial alterations in a case of myopathy. Ultrastruct Pathol 2014; 38:204-10. [PMID: 24579828 DOI: 10.3109/01913123.2014.888114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Mitochondrial alterations are the most common feature of human myopathies. A biopsy of quadriceps muscle from a 50-year-old woman exhibiting myopathic symptoms was examined by transmission electron microscopy. Biopsied fibers from quadriceps muscle displayed numerous subsarcolemmal mitochondria that contained crystalloids. Numbering 1-6 per organelle, these consisted of rows of punctuate densities measuring ∼0.34 nm; the parallel rows of these dots had a periodicity of ∼0.8 nm. The crystalloids were ensconced within cristae or in the outer compartment. Some mitochondria without crystalloids had circumferential cristae, leaving a membrane-free center that was filled with a farinaceous material. Other scattered fibrocyte defects included disruption of the contractile apparatus or its sporadic replacement by a finely punctuate material in some myofibers. Intramitochondrial crystalloids, although morphologically striking, do not impair organelle physiology to a significant degree, so the muscle weakness of the patient must originate elsewhere.
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49
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Bottani E, Giordano C, Civiletto G, Di Meo I, Auricchio A, Ciusani E, Marchet S, Lamperti C, d'Amati G, Viscomi C, Zeviani M. AAV-mediated liver-specific MPV17 expression restores mtDNA levels and prevents diet-induced liver failure. Mol Ther 2014; 22:10-7. [PMID: 24247928 PMCID: PMC3880585 DOI: 10.1038/mt.2013.230] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 08/21/2013] [Indexed: 12/23/2022] Open
Abstract
Mutations in human MPV17 cause a hepatocerebral form of mitochondrial DNA depletion syndrome (MDS) hallmarked by early-onset liver failure, leading to premature death. Liver transplantation and frequent feeding using slow-release carbohydrates are the only available therapies, although surviving patients eventually develop slowly progressive peripheral and central neuropathy. The physiological role of Mpv17, including its functional link to mitochondrial DNA (mtDNA) maintenance, is still unclear. We show here that Mpv17 is part of a high molecular weight complex of unknown composition, which is essential for mtDNA maintenance in critical tissues, i.e. liver, of a Mpv17 knockout mouse model. On a standard diet, Mpv17-/- mouse shows hardly any symptom of liver dysfunction, but a ketogenic diet (KD) leads these animals to liver cirrhosis and failure. However, when expression of human MPV17 is carried out by adeno-associated virus (AAV)-mediated gene replacement, the Mpv17 knockout mice are able to reconstitute the Mpv17-containing supramolecular complex, restore liver mtDNA copy number and oxidative phosphorylation (OXPHOS) proficiency, and prevent liver failure induced by the KD. These results open new therapeutic perspectives for the treatment of MPV17-related liver-specific MDS.
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Affiliation(s)
- Emanuela Bottani
- Unit of Molecular Neurogenetics, The Foundation “Carlo Besta” Institute of Neurology IRCCS, Milan, Italy
| | - Carla Giordano
- Department of Radiological, Oncological, and Pathological Sciences, Sapienza University, Roma, Italy
| | - Gabriele Civiletto
- Unit of Molecular Neurogenetics, The Foundation “Carlo Besta” Institute of Neurology IRCCS, Milan, Italy
| | - Ivano Di Meo
- Unit of Molecular Neurogenetics, The Foundation “Carlo Besta” Institute of Neurology IRCCS, Milan, Italy
| | - Alberto Auricchio
- Department of Pediatrics, Division of Medical Genetics, Telethon Institute of Genetics and Medicine, “Federico II” University, Naples, Italy
| | - Emilio Ciusani
- Laboratory of Clinical Pathology and Medical Genetics, The Foundation “Carlo Besta” Institute of Neurology IRCCS, Milan, Italy
| | - Silvia Marchet
- Unit of Molecular Neurogenetics, The Foundation “Carlo Besta” Institute of Neurology IRCCS, Milan, Italy
| | - Costanza Lamperti
- Unit of Molecular Neurogenetics, The Foundation “Carlo Besta” Institute of Neurology IRCCS, Milan, Italy
| | - Giulia d'Amati
- Department of Radiological, Oncological, and Pathological Sciences, Sapienza University, Roma, Italy
| | - Carlo Viscomi
- Unit of Molecular Neurogenetics, The Foundation “Carlo Besta” Institute of Neurology IRCCS, Milan, Italy
| | - Massimo Zeviani
- Unit of Molecular Neurogenetics, The Foundation “Carlo Besta” Institute of Neurology IRCCS, Milan, Italy
- MRC-Mitochondrial Biology Unit, Cambridge, UK
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50
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Brunetti D, Dusi S, Giordano C, Lamperti C, Morbin M, Fugnanesi V, Marchet S, Fagiolari G, Sibon O, Moggio M, d'Amati G, Tiranti V. Pantethine treatment is effective in recovering the disease phenotype induced by ketogenic diet in a pantothenate kinase-associated neurodegeneration mouse model. ACTA ACUST UNITED AC 2013; 137:57-68. [PMID: 24316510 PMCID: PMC3891449 DOI: 10.1093/brain/awt325] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Pantothenate kinase-associated neurodegeneration, caused by mutations in the PANK2 gene, is an autosomal recessive disorder characterized by dystonia, dysarthria, rigidity, pigmentary retinal degeneration and brain iron accumulation. PANK2 encodes the mitochondrial enzyme pantothenate kinase type 2, responsible for the phosphorylation of pantothenate or vitamin B5 in the biosynthesis of co-enzyme A. A Pank2 knockout (Pank2−/−) mouse model did not recapitulate the human disease but showed azoospermia and mitochondrial dysfunctions. We challenged this mouse model with a low glucose and high lipid content diet (ketogenic diet) to stimulate lipid use by mitochondrial beta-oxidation. In the presence of a shortage of co-enzyme A, this diet could evoke a general impairment of bioenergetic metabolism. Only Pank2−/− mice fed with a ketogenic diet developed a pantothenate kinase-associated neurodegeneration-like syndrome characterized by severe motor dysfunction, neurodegeneration and severely altered mitochondria in the central and peripheral nervous systems. These mice also showed structural alteration of muscle morphology, which was comparable with that observed in a patient with pantothenate kinase-associated neurodegeneration. We here demonstrate that pantethine administration can prevent the onset of the neuromuscular phenotype in mice suggesting the possibility of experimental treatment in patients with pantothenate kinase-associated neurodegeneration.
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Affiliation(s)
- Dario Brunetti
- 1 Unit of Molecular Neurogenetics, Foundation IRCCS Neurological Institute C. Besta, Milan, Italy
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