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Heidler J, Cabrera-Orefice A, Wittig I, Heyne E, Tomczak JN, Petersen B, Henze D, Pohjoismäki JLO, Szibor M. Hyperbaric oxygen treatment reveals spatiotemporal OXPHOS plasticity in the porcine heart. PNAS NEXUS 2024; 3:pgae210. [PMID: 38881840 PMCID: PMC11179111 DOI: 10.1093/pnasnexus/pgae210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 05/17/2024] [Indexed: 06/18/2024]
Abstract
Cardiomyocytes meet their high ATP demand almost exclusively by oxidative phosphorylation (OXPHOS). Adequate oxygen supply is an essential prerequisite to keep OXPHOS operational. At least two spatially distinct mitochondrial subpopulations facilitate OXPHOS in cardiomyocytes, i.e. subsarcolemmal (SSM) and interfibrillar mitochondria (IFM). Their intracellular localization below the sarcolemma or buried deep between the sarcomeres suggests different oxygen availability. Here, we studied SSM and IFM isolated from piglet hearts and found significantly lower activities of electron transport chain enzymes and F1FO-ATP synthase in IFM, indicative for compromised energy metabolism. To test the contribution of oxygen availability to this outcome, we ventilated piglets under hyperbaric hyperoxic (HBO) conditions for 240 min. HBO treatment raised OXPHOS enzyme activities in IFM to the level of SSM. Complexome profiling analysis revealed that a high proportion of the F1FO-ATP synthase in the IFM was in a disassembled state prior to the HBO treatment. Upon increased oxygen availability, the enzyme was found to be largely assembled, which may account for the observed increase in OXPHOS complex activities. Although HBO also induced transcription of genes involved in mitochondrial biogenesis, a full proteome analysis revealed only minimal alterations, meaning that HBO-mediated tissue remodeling is an unlikely cause for the observed differences in OXPHOS. We conclude that a previously unrecognized oxygen-regulated mechanism endows cardiac OXPHOS with spatiotemporal plasticity that may underlie the enormous metabolic and contractile adaptability of the heart.
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Affiliation(s)
- Juliana Heidler
- Functional Proteomics, Institute of Cardiovascular Physiology, Faculty of Medicine, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
- Experimental Vascular Surgery, University Clinic of Vascular Surgery, Innsbruck Medical University, 6020 Innsbruck, Austria
| | - Alfredo Cabrera-Orefice
- Functional Proteomics, Institute of Cardiovascular Physiology, Faculty of Medicine, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
| | - Ilka Wittig
- Functional Proteomics, Institute of Cardiovascular Physiology, Faculty of Medicine, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
| | - Estelle Heyne
- Department of Cardiothoracic Surgery, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Friedrich Schiller University of Jena, 07747 Jena, Germany
| | - Jan-Niklas Tomczak
- Functional Proteomics, Institute of Cardiovascular Physiology, Faculty of Medicine, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
| | - Bjoern Petersen
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institute (FLI), 31535 Mariensee, Germany
| | - Dirk Henze
- Praxis für Anästhesiologie, Dr. Henze & Partner GbR, 06116 Halle (Saale), Germany
| | - Jaakko L O Pohjoismäki
- Department of Environmental and Biological Sciences, University of Eastern Finland, 80101 Joensuu, Finland
| | - Marten Szibor
- Department of Cardiothoracic Surgery, Center for Sepsis Control and Care (CSCC), Jena University Hospital, Friedrich Schiller University of Jena, 07747 Jena, Germany
- Faculty of Medicine and Health Technology, Tampere University, 33014 Tampere, Finland
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2
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Mendes D, Silva AM, Oliveira MM, Andrade PB, Videira RA. An Experimental Approach to Address the Functional Relationship between Antioxidant Enzymes and Mitochondrial Respiratory Complexes. Methods Protoc 2023; 6:mps6020032. [PMID: 37104014 PMCID: PMC10142429 DOI: 10.3390/mps6020032] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/18/2023] [Accepted: 03/21/2023] [Indexed: 04/28/2023] Open
Abstract
Mitochondrial dysfunction and cytosolic oxidative stress are pathological biomarkers interlinked in several chronic diseases and cellular toxicity promoted by high-energy radiation or xenobiotics. Thus, assessing the activities of the mitochondrial redox chain complexes and the cytosolic antioxidant enzymes in the same cell culture system is a valuable approach to addressing the challenge of chronic diseases or unveiling the molecular mechanisms underlying the toxicity of physical and chemical stress agents. The present article gathers the experimental procedures to obtain, from isolated cells, a mitochondria-free cytosolic fraction and a mitochondria-rich fraction. Furthermore, we describe the methodologies to evaluate the activity of the main antioxidant enzymes in the mitochondria-free cytosolic fraction (superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase), and the activity of the individual mitochondrial complexes I, II and IV, as well as the conjugated activity of complexes I-III and complexes II-III in the mitochondria-rich fraction. The protocol to test the citrate synthase activity was also considered and used to normalize complexes. The procedures were optimized within an experimental setup to allow that each condition to be tested only requires sampling of one T-25 flask of cells 2D cultured, as the typical results presented and discussed here.
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Affiliation(s)
- Daniela Mendes
- REQUIMTE/LAQV, Laboratory of Pharmacognosy, Department of Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, nº 228, 4050-313 Porto, Portugal
| | - Ana Maria Silva
- Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal
| | - Maria Manuel Oliveira
- Chemistry Center-Vila Real (CQ-VR), Chemistry Department, School of Life and Environmental Sciences, University of Trás-os-Montes e Alto Douro, UTAD, 5001-801 Vila Real, Portugal
| | - Paula B Andrade
- REQUIMTE/LAQV, Laboratory of Pharmacognosy, Department of Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, nº 228, 4050-313 Porto, Portugal
| | - Romeu A Videira
- REQUIMTE/LAQV, Laboratory of Pharmacognosy, Department of Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, nº 228, 4050-313 Porto, Portugal
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3
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Age-associated alterations of brain mitochondria energetics. Biochem Biophys Res Commun 2023; 643:1-7. [PMID: 36584587 DOI: 10.1016/j.bbrc.2022.12.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 11/28/2022] [Accepted: 12/22/2022] [Indexed: 12/25/2022]
Abstract
The study aimed to explore the role of age-associated elevated cytosolic Ca2+ in changes of brain mitochondria energetic processes. Two groups of rats, young adults (4 months) and advanced old (24 months), were evaluated for potential alterations of mitochondrial parameters, the oxidative phosphorylation (OxPhos), membrane potential, calcium retention capacity, activity of glutamate/aspartate carrier (aralar), and ROS formation. We demonstrated that the brain mitochondria of older animals have a lower resistance to Ca2+ stress with resulting consequences. The suppressed complex I OxPhos and decreased membrane potential were accompanied by reduction of the Ca2+ threshold required for induction of mPTP. The Ca2+ binding sites of mitochondrial aralar mediated a lower activity of old brain mitochondria. The altered interaction between aralar and mPTP may underlie mitochondrial dysregulation leading to energetic depression during aging. At the advanced stages of aging, the declined metabolism is accompanied by the diminished oxidative background.
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Mitochondrial DNA Profiling by Fractal Lacunarity to Characterize the Senescent Phenotype as Normal Aging or Pathological Aging. FRACTAL AND FRACTIONAL 2022. [DOI: 10.3390/fractalfract6040219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Biocomplexity, chaos, and fractality can explain the heterogeneity of aging individuals by regarding longevity as a “secondary product” of the evolution of a dynamic nonlinear system. Genetic-environmental interactions drive the individual senescent phenotype toward normal, pathological, or successful aging. Mitochondrial dysfunctions and mitochondrial DNA (mtDNA) mutations represent a possible mechanism shared by disease(s) and the aging process. This study aims to characterize the senescent phenotype and discriminate between normal (nA) and pathological (pA) aging by mtDNA mutation profiling. MtDNA sequences from hospitalized and non-hospitalized subjects (age-range: 65–89 years) were analyzed and compared to the revised Cambridge Reference Sequence (rCRS). Fractal properties of mtDNA sequences were displayed by chaos game representation (CGR) method, previously modified to deal with heteroplasmy. Fractal lacunarity analysis was applied to characterize the senescent phenotype on the basis of mtDNA sequence mutations. Lacunarity parameter β, from our hyperbola model function, was statistically different (p < 0.01) between the nA and pA groups. Parameter β cut-off value at 1.26 × 10−3 identifies 78% nA and 80% pA subjects. This also agrees with the presence of MT-CO gene variants, peculiar to nA (C9546m, 83%) and pA (T9900w, 80%) mtDNA, respectively. Fractal lacunarity can discriminate the senescent phenotype evolving as normal or pathological aging by individual mtDNA mutation profile.
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5
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Treatment and Management of Hereditary Metabolic Myopathies. Neuromuscul Disord 2022. [DOI: 10.1016/b978-0-323-71317-7.00023-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Rodríguez-Enríquez S, Robledo-Cadena DX, Gallardo-Pérez JC, Pacheco-Velázquez SC, Vázquez C, Saavedra E, Vargas-Navarro JL, Blanco-Carpintero BA, Marín-Hernández Á, Jasso-Chávez R, Encalada R, Ruiz-Godoy L, Aguilar-Ponce JL, Moreno-Sánchez R. Acetate Promotes a Differential Energy Metabolic Response in Human HCT 116 and COLO 205 Colon Cancer Cells Impacting Cancer Cell Growth and Invasiveness. Front Oncol 2021; 11:697408. [PMID: 34414111 PMCID: PMC8370060 DOI: 10.3389/fonc.2021.697408] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 07/15/2021] [Indexed: 12/26/2022] Open
Abstract
Under dysbiosis, a gut metabolic disorder, short-chain carboxylic acids (SCCAs) are secreted to the lumen, affecting colorectal cancer (CRC) development. Butyrate and propionate act as CRC growth inhibitors, but they might also serve as carbon source. In turn, the roles of acetate as metabolic fuel and protein acetylation promoter have not been clearly elucidated. To assess whether acetate favors CRC growth through active mitochondrial catabolism, a systematic study evaluating acetate thiokinase (AcK), energy metabolism, cell proliferation, and invasiveness was performed in two CRC cell lines incubated with physiological SCCAs concentrations. In COLO 205, acetate (+glucose) increased the cell density (50%), mitochondrial protein content (3–10 times), 2-OGDH acetylation, and oxidative phosphorylation (OxPhos) flux (36%), whereas glycolysis remained unchanged vs. glucose-cultured cells; the acetate-induced OxPhos activation correlated with a high AcK activity, content, and acetylation (1.5–6-fold). In contrast, acetate showed no effect on HCT116 cell growth, OxPhos, AcK activity, protein content, and acetylation. However, a substantial increment in the HIF-1α content, HIF-1α-glycolytic protein targets (1–2.3 times), and glycolytic flux (64%) was observed. Butyrate and propionate decreased the growth of both CRC cells by impairing OxPhos flux through mitophagy and mitochondrial fragmentation activation. It is described, for the first time, the role of acetate as metabolic fuel for ATP supply in CRC COLO 205 cells to sustain proliferation, aside from its well-known role as protein epigenetic regulator. The level of AcK determined in COLO 205 cells was similar to that found in human CRC biopsies, showing its potential role as metabolic marker.
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Affiliation(s)
| | | | | | | | - Citlali Vázquez
- Departamento de Bioquímica, Instituto Nacional de Cardiología, México, Mexico
| | - Emma Saavedra
- Departamento de Bioquímica, Instituto Nacional de Cardiología, México, Mexico
| | | | | | | | | | - Rusely Encalada
- Departamento de Bioquímica, Instituto Nacional de Cardiología, México, Mexico
| | - Luz Ruiz-Godoy
- Banco de Tumores, Instituto Nacional de Cancerología, México, Mexico
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7
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Wang W, Sun Y, Lin Y, Xu X, Zhao D, Ji K, Li W, Zhao Y, Yan C. A novel nonsense variant in MT-CO3 causes MELAS syndrome. Neuromuscul Disord 2021; 31:558-565. [PMID: 33863631 DOI: 10.1016/j.nmd.2021.02.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 02/11/2021] [Accepted: 02/26/2021] [Indexed: 11/18/2022]
Abstract
Both mitochondrial and nuclear gene mutations can cause cytochrome c oxidase (COX, complex Ⅳ) dysfunction, leading to mitochondrial diseases. Although numerous diseases caused by defects of the COX subunits or COX assembly factors have been documented, clinical cases directly related to mitochondrial cytochrome c oxidase subunit 3 gene (MT-CO3) mutations are relatively rare. Here, we report a 47-year-old female patient presented with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome. Muscle pathology revealed ragged-red fibres and remarkable COX-deficient muscle fibres. Muscle mitochondrial DNA sequencing analysis identified a novel MT-CO3 variant (m.9553G>A) that changed a highly conserved amino acid to a stop codon (p.Trp116*). This variant was heteroplasmic in multiple tissues, where the mutation load was 13% in oral epithelial cells, 89% in muscle samples, and not detectable in the peripheral blood lymphocytes. Single muscle fiber PCR analysis showed clear segregation of the mutation load with COX deficient fibres. Western blot analysis of the muscle samples revealed a significant decrease in the levels of COX1, COX2, COX3, COX4 and UQCRC2. COX respiration activity was remarkably reduced (58.84%) relative to the controls according to spectrophotometric assays. Taken together, our results indicated that this m.9553G>A variant may be responsible for the MELAS symdrome in the proband by affecting the stability and function of COX. The study expands the clinical and molecular spectrum of COX3-specific mitochondrial diseases.
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Affiliation(s)
- Wei Wang
- Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road Jinan, Jinan, Shandong 250012 China
| | - Yuan Sun
- Department of Neurology, Qilu Hospital (Qingdao), Cheeloo College of Medicine, Shandong University, Qingdao, Shandong 266035 China
| | - Yan Lin
- Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road Jinan, Jinan, Shandong 250012 China
| | - Xuebi Xu
- Department of Neurology, First Affiliated Hospital of Wenzhou Medical University, Nanbaixiang Street, Ouhai District, Wenzhou 325000, China
| | - Dandan Zhao
- Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road Jinan, Jinan, Shandong 250012 China
| | - Kunqian Ji
- Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road Jinan, Jinan, Shandong 250012 China.
| | - Wei Li
- Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road Jinan, Jinan, Shandong 250012 China
| | - Yuying Zhao
- Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road Jinan, Jinan, Shandong 250012 China
| | - Chuanzhu Yan
- Research Institute of Neuromuscular and Neurodegenerative Diseases and Department of Neurology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, No. 107 West Wenhua Road Jinan, Jinan, Shandong 250012 China; Department of Neurology, Qilu Hospital (Qingdao), Cheeloo College of Medicine, Shandong University, Qingdao, Shandong 266035 China; Mitochondrial Medicine Laboratory, Qilu Hospital (Qingdao), Shandong University, Qingdao, Shandong 266035 China; Brain Science Research Institute, Shandong University, Jinan, Shandong 250000, China.
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8
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Emelyanova L, Bai X, Yan Y, Bosnjak ZJ, Kress D, Warner C, Kroboth S, Rudic T, Kaushik S, Stoeckl E, Ross GR, Rizvi F, Tajik AJ, Jahangir A. Biphasic effect of metformin on human cardiac energetics. Transl Res 2021; 229:5-23. [PMID: 33045408 PMCID: PMC10655614 DOI: 10.1016/j.trsl.2020.10.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 09/30/2020] [Accepted: 10/05/2020] [Indexed: 02/01/2023]
Abstract
Metformin is the first-line medication for treatment of type 2 diabetes and has been shown to reduce heart damage and death. However, mechanisms by which metformin protects human heart remain debated. The aim of the study was to evaluate the cardioprotective effect of metformin on cardiomyocytes derived from human-induced pluripotent stem cells (hiPSC-CMs) and mitochondria isolated from human cardiac tissue. At concentrations ≤2.5 mM, metformin significantly increased oxygen consumption rate (OCR) in the hiPSC-CMs by activating adenosine monophosphate activated protein kinase (AMPK)-dependent signaling and enhancing mitochondrial biogenesis. This effect was abrogated by compound C, an inhibitor of AMPK. At concentrations >5 mM, metformin inhibited the cellular OCR and triggered metabolic reprogramming by enhancing glycolysis and glutaminolysis in the cardiomyocytes. In isolated cardiac mitochondria, metformin did not increase the OCR at any concentrations but inhibited the OCR starting at 1 mM through direct inhibition of electron-transport chain complex I. This was associated with reduction of superoxide production and attenuation of Ca2+-induced mitochondrial permeability transition pore (mPTP) opening in the mitochondria. Thus, in human heart, metformin might improve cardioprotection due to its biphasic effect on mitochondria: at low concentrations, it activates mitochondrial biogenesis via AMPK signaling and increases the OCR; at high concentrations, it inhibits the respiration by directly affecting the activity of complex I, reduces oxidative stress and delays mPTP formation. Moreover, metformin at high concentrations causes metabolic reprogramming by enhancing glycolysis and glutaminolysis. These effects can be a beneficial adjunct to patients with impaired endogenous cardioprotective responses.
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Affiliation(s)
- Larisa Emelyanova
- Center for Integrative Research on Cardiovascular Aging, Advocate Aurora Research Institute, Milwaukee, Wisconsin.
| | - Xiaowen Bai
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Yasheng Yan
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Zeljko J Bosnjak
- Departments of Medicine and Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - David Kress
- Aurora Cardiovascular and Thoracic Services, St. Luke's Medical Center, Advocate Aurora Health Care, Milwaukee, Wisconsin
| | - Catherine Warner
- Center for Integrative Research on Cardiovascular Aging, Advocate Aurora Research Institute, Milwaukee, Wisconsin
| | - Stacie Kroboth
- Aurora Cardiovascular and Thoracic Services, St. Luke's Medical Center, Advocate Aurora Health Care, Milwaukee, Wisconsin
| | - Teodore Rudic
- Center for Integrative Research on Cardiovascular Aging, Advocate Aurora Research Institute, Milwaukee, Wisconsin
| | - Sirisha Kaushik
- Center for Integrative Research on Cardiovascular Aging, Advocate Aurora Research Institute, Milwaukee, Wisconsin
| | - Elizabeth Stoeckl
- Center for Integrative Research on Cardiovascular Aging, Advocate Aurora Research Institute, Milwaukee, Wisconsin
| | - Gracious R Ross
- Center for Integrative Research on Cardiovascular Aging, Advocate Aurora Research Institute, Milwaukee, Wisconsin
| | - Farhan Rizvi
- Center for Integrative Research on Cardiovascular Aging, Advocate Aurora Research Institute, Milwaukee, Wisconsin
| | - A Jamil Tajik
- Aurora Cardiovascular and Thoracic Services, St. Luke's Medical Center, Advocate Aurora Health Care, Milwaukee, Wisconsin
| | - Arshad Jahangir
- Aurora Cardiovascular and Thoracic Services, St. Luke's Medical Center, Advocate Aurora Health Care, Milwaukee, Wisconsin
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9
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Murgia M, Tan J, Geyer PE, Doll S, Mann M, Klopstock T. Proteomics of Cytochrome c Oxidase-Negative versus -Positive Muscle Fiber Sections in Mitochondrial Myopathy. Cell Rep 2020; 29:3825-3834.e4. [PMID: 31851916 DOI: 10.1016/j.celrep.2019.11.055] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 09/30/2019] [Accepted: 11/13/2019] [Indexed: 12/15/2022] Open
Abstract
The mosaic distribution of cytochrome c oxidase+ (COX+) and COX- muscle fibers in mitochondrial disorders allows the sampling of fibers with compensated and decompensated mitochondrial function from the same individual. We apply laser capture microdissection to excise individual COX+ and COX- fibers from the biopsies of mitochondrial myopathy patients. Using mass spectrometry-based proteomics, we quantify >4,000 proteins per patient. While COX+ fibers show a higher expression of respiratory chain components, COX- fibers display protean adaptive responses, including upregulation of mitochondrial ribosomes, translation proteins, and chaperones. Upregulated proteins include C1QBP, required for mitoribosome formation and protein synthesis, and STOML2, which organizes cardiolipin-enriched microdomains and the assembly of respiratory supercomplexes. Factoring in fast/slow fiber type, COX- slow fibers show a compensatory upregulation of beta-oxidation, the AAA+ protease AFG3L1, and the OPA1-dependent cristae remodeling program. These findings reveal compensatory mechanisms in muscle fibers struggling with energy shortage and metabolic stress.
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Affiliation(s)
- Marta Murgia
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany; Department of Biomedical Sciences, University of Padova, Via Ugo Bassi, 58/B, 35131 Padua, Italy
| | - Jing Tan
- Friedrich Baur Institute, Department of Neurology, University of Munich, 80336 Munich, Germany
| | - Philipp E Geyer
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Sophia Doll
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Matthias Mann
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany; NNF Center for Protein Research, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark.
| | - Thomas Klopstock
- Friedrich Baur Institute, Department of Neurology, University of Munich, 80336 Munich, Germany; German Center for Neurodegenerative Diseases (DZNE), Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
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10
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Lehmann Urban D, Motlagh Scholle L, Wagner M, Ludolph AC, Rosenbohm A. The m.9143T>C Variant: Recurrent Infections and Immunodeficiency as an Extension of the Phenotypic Spectrum in MT-ATP6 Mutations? Diseases 2020; 8:diseases8020019. [PMID: 32527054 PMCID: PMC7348873 DOI: 10.3390/diseases8020019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/05/2020] [Accepted: 06/07/2020] [Indexed: 11/22/2022] Open
Abstract
Pathogenic variants in the MT-ATP6 are a well-known cause for maternally inherited mitochondrial disorders associated with a wide range of clinical phenotypes. Here, we present a 31- year old female with insulin-dependent diabetes mellitus, recurrent lactic acidosis and ketoacidosis recurrent infections with suspected immunodeficiency with T cell lymphopenia and hypogammaglobulinemia as well as proximal tetraparesis with severe muscle and limb pain and rapid physical exhaustion. Muscle biopsy and respiratory chain activities were normal. Single-exome sequencing revealed a variant in the MT-ATP6 gene: m.9143T>C. Analysis of further specimen of the index and mother (segregation studies) revealed the highest mutation load in muscle (99% level of mtDNA heteroplasmy) of the index patient. Interestingly, acute metabolic and physical decompensation during recurrent illness was documented to be a common clinical feature in patients with MT-ATP6 variants. However, it was not mentioned as a key symptom. Thus, we suggest that the clinical spectrum might be expanded in ATP6-associated diseases.
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Affiliation(s)
- Diana Lehmann Urban
- Department of Neurology, Ulm University, 89081 Ulm, Germany; (A.C.L.); (A.R.)
- Correspondence: ; Tel.: +49-(0)731-177-1201
| | | | - Matias Wagner
- Institute of Human Genetics, School of Medicine, Technical University Munich, 81675 Munich, Germany;
- Institute of Neurogenomics, Helmholtz Zentrum München, 85764 Munich, Germany
| | - Albert C. Ludolph
- Department of Neurology, Ulm University, 89081 Ulm, Germany; (A.C.L.); (A.R.)
| | - Angela Rosenbohm
- Department of Neurology, Ulm University, 89081 Ulm, Germany; (A.C.L.); (A.R.)
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11
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Camptocormia as a Novel Phenotype in a Heterozygous POLG2 Mutation. Diagnostics (Basel) 2020; 10:diagnostics10020068. [PMID: 31991853 PMCID: PMC7168901 DOI: 10.3390/diagnostics10020068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 01/19/2020] [Accepted: 01/23/2020] [Indexed: 12/04/2022] Open
Abstract
Mitochondrial dysfunction is known to play a key role in the pathophysiological pathway of neurodegenerative disorders. Nuclear-encoded proteins are involved in mtDNA replication, including DNA polymerase gamma, which is the only known replicative mtDNA polymerase, encoded by nuclear genes Polymerase gamma 1 (POLG) and Polymerase gamma 2 (POLG2). POLG mutations are well-known as a frequent cause of mitochondrial myopathies of nuclear origin. However, only rare descriptions of POLG2 mutations leading to mitochondriopathies exist. Here we describe a 68-year-old woman presenting with a 20-year history of camptocormia, mild proximal weakness, and moderate CK increase. Muscle histology showed COX-negative fibres. Genetic analysis by next generation sequencing revealed an already reported heterozygous c.1192-8_1207dup24 mutation in the POLG2 gene. This is the first report on a POLG2 mutation leading to camptocormia as the main clinical phenotype, extending the phenotypic spectrum of POLG2 associated diseases. This underlines the broad phenotypic spectrum found in mitochondrial diseases, especially in mitochondrial disorders of nuclear origin.
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12
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Finsterer J. Viability of diffusion tensor imaging for assessing retro-chiasmatic involvement in Kearns-Sayre syndrome remains elusive. Neuroradiology 2019; 62:131-132. [PMID: 31807840 DOI: 10.1007/s00234-019-02325-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 11/14/2019] [Indexed: 11/25/2022]
Affiliation(s)
- Josef Finsterer
- Neurological Department, Krankenanstalt Rudolfstiftung, Messerli Institute, Postfach 20, 1180, Vienna, Austria.
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13
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Neves D, Valentão P, Bernardo J, Oliveira MC, Ferreira JM, Pereira DM, Andrade PB, Videira RA. A new insight on elderberry anthocyanins bioactivity: Modulation of mitochondrial redox chain functionality and cell redox state. J Funct Foods 2019. [DOI: 10.1016/j.jff.2019.03.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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14
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Rocha MC, Rosa HS, Grady JP, Blakely EL, He L, Romain N, Haller RG, Newman J, McFarland R, Ng YS, Gorman GS, Schaefer AM, Tuppen HA, Taylor RW, Turnbull DM. Pathological mechanisms underlying single large-scale mitochondrial DNA deletions. Ann Neurol 2019; 83:115-130. [PMID: 29283441 PMCID: PMC5893934 DOI: 10.1002/ana.25127] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Revised: 12/01/2017] [Accepted: 12/21/2017] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Single, large-scale deletions in mitochondrial DNA (mtDNA) are a common cause of mitochondrial disease. This study aimed to investigate the relationship between the genetic defect and molecular phenotype to improve understanding of pathogenic mechanisms associated with single, large-scale mtDNA deletions in skeletal muscle. METHODS We investigated 23 muscle biopsies taken from adult patients (6 males/17 females with a mean age of 43 years) with characterized single, large-scale mtDNA deletions. Mitochondrial respiratory chain deficiency in skeletal muscle biopsies was quantified by immunoreactivity levels for complex I and complex IV proteins. Single muscle fibers with varying degrees of deficiency were selected from 6 patient biopsies for determination of mtDNA deletion level and copy number by quantitative polymerase chain reaction. RESULTS We have defined 3 "classes" of single, large-scale deletion with distinct patterns of mitochondrial deficiency, determined by the size and location of the deletion. Single fiber analyses showed that fibers with greater respiratory chain deficiency harbored higher levels of mtDNA deletion with an increase in total mtDNA copy number. For the first time, we have demonstrated that threshold levels for complex I and complex IV deficiency differ based on deletion class. INTERPRETATION Combining genetic and immunofluorescent assays, we conclude that thresholds for complex I and complex IV deficiency are modulated by the deletion of complex-specific protein-encoding genes. Furthermore, removal of mt-tRNA genes impacts specific complexes only at high deletion levels, when complex-specific protein-encoding genes remain. These novel findings provide valuable insight into the pathogenic mechanisms associated with these mutations. Ann Neurol 2018;83:115-130.
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Affiliation(s)
- Mariana C Rocha
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Hannah S Rosa
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - John P Grady
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Emma L Blakely
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.,National Health Service Highly Specialised Mitochondrial Diagnostic Laboratory, Newcastle upon Tyne Hospitals, National Health Service Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Langping He
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.,National Health Service Highly Specialised Mitochondrial Diagnostic Laboratory, Newcastle upon Tyne Hospitals, National Health Service Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Nadine Romain
- Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX.,Institute for Exercise and Environmental Medicine of Texas Health Presbyterian Hospital, Dallas, TX
| | - Ronald G Haller
- Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX.,Institute for Exercise and Environmental Medicine of Texas Health Presbyterian Hospital, Dallas, TX
| | - Jane Newman
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Robert McFarland
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Yi Shiau Ng
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Grainne S Gorman
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Andrew M Schaefer
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Helen A Tuppen
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Robert W Taylor
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.,National Health Service Highly Specialised Mitochondrial Diagnostic Laboratory, Newcastle upon Tyne Hospitals, National Health Service Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Doug M Turnbull
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
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15
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Metabolic Maturation during Muscle Stem Cell Differentiation Is Achieved by miR-1/133a-Mediated Inhibition of the Dlk1-Dio3 Mega Gene Cluster. Cell Metab 2018; 27:1026-1039.e6. [PMID: 29606596 DOI: 10.1016/j.cmet.2018.02.022] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Revised: 12/20/2017] [Accepted: 02/23/2018] [Indexed: 12/20/2022]
Abstract
Muscle stem cells undergo a dramatic metabolic switch to oxidative phosphorylation during differentiation, which is achieved by massively increased mitochondrial activity. Since expression of the muscle-specific miR-1/133a gene cluster correlates with increased mitochondrial activity during muscle stem cell (MuSC) differentiation, we examined the potential role of miR-1/133a in metabolic maturation of skeletal muscles in mice. We found that miR-1/133a downregulate Mef2A in differentiated myocytes, thereby suppressing the Dlk1-Dio3 gene cluster, which encodes multiple microRNAs inhibiting expression of mitochondrial genes. Loss of miR-1/133a in skeletal muscles or increased Mef2A expression causes continuous high-level expression of the Dlk1-Dio3 gene cluster, compromising mitochondrial function. Failure to terminate the stem cell-like metabolic program characterized by high-level Dlk1-Dio3 gene cluster expression initiates profound changes in muscle physiology, essentially abrogating endurance running. Our results suggest a major role of miR-1/133a in metabolic maturation of skeletal muscles but exclude major functions in muscle development and MuSC maintenance.
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16
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Abstract
The development of effective medicines to break or delay the progressive brain degeneration underlying cognitive decline and dementia that characterize Alzheimer's disease (AD) is one of the greatest challenges of our time. In the present work, a selective pool of polyphenols, obtained from the white wine by adsorption to polyvinylpyrrolidone polymer (PVPP), was used to prepare a polyphenols-enriched diet, supplementing the drinking water with 100 mg/L (expressed as gallic acid equivalent) of wine polyphenolic extract. The impact of the daily consumption of water supplemented with polyphenols for 2 months on brain of 10-month-old 3xTg-AD and NonTg mice was evaluated, considering effects on the redox state of cells, levels of amyloid-β peptides, mitochondrial bioenergetics and fatty acid profile of whole membrane phospholipids. The polyphenols-enriched diet promotes brain accumulation of catechin and hydroxybenzoic acid derivatives, and modulates the redox state of 3xTg-AD brain cells, increasing both glutathione/glutathione disulfide ratio and catalase activity and decreasing membrane lipids oxidation. Additionally, the functional diet decreases the 3xTg-AD brain levels of both amyloid-β peptides, Aβ1-40 and Aβ1-42. However, the brain mitochondrial bioenergetic dysfunction of 3xTg-AD animals was not attenuated by the polyphenols-enriched diet. Lipidomic studies showed that this functional diet modulates membrane lipid composition of brain cells, increasing C22:6n-3 (docosahexanoic acid) and decreasing C20:4n-6 (arachidonic acid) levels, which may have beneficial impact on the chronic inflammatory process associated with AD pathology. Altogether, these results indicate that the oral administration of this polyphenols-enriched diet promotes significant benefits in multiple aspects of the pathophysiological cascade associated with the neuropathology developed by 3xTg-AD mice.
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17
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Urbanová M, Mráz M, Ďurovcová V, Trachta P, Kloučková J, Kaválková P, Haluzíková D, Lacinová Z, Hansíková H, Wenchich L, Kršek M, Haluzík M. The effect of very-low-calorie diet on mitochondrial dysfunction in subcutaneous adipose tissue and peripheral monocytes of obese subjects with type 2 diabetes mellitus. Physiol Res 2017; 66:811-822. [PMID: 28730835 DOI: 10.33549/physiolres.933469] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Mitochondrial dysfunction is a potentially important player in the development of insulin resistance and type 2 diabetes mellitus (T2DM). We investigated the changes of mRNA expression of genes encoding main enzymatic complexes of mitochondrial respiratory chain in subcutaneous adipose tissue (SCAT) and peripheral monocytes (PM) of 11 subjects with simple obesity (OB), 16 obese patients with T2DM and 17 healthy lean subjects (C) before and after very low-calorie diet (VLCD) using quantitative real time PCR. At baseline in SCAT, both T2DM and OB group had decreased mRNA expression of all investigated mitochondrial genes with the exception of 2 complex I (NDUFA 12) and complex IV (COX 4/1) enzymes in OB subjects. In contrast, in PM only the expression of complex I enzymes NDUFA 12 and MT-ND5 was reduced in both T2DM and OB subjects along with decreased expression of citrate synthase (CS) in T2DM group. Additionally, T2DM subjects showed reduced activity of pyruvate dehydrogenase and complex IV in peripheral blood elements. VLCD further decreased mRNA expression of CS and complex I (NT-ND5) and II (SDHA) enzymes in SCAT and complex IV (COX4/1) and ATP synthase in PM of T2DM group, while increasing the activity of complex IV in their peripheral blood elements. We conclude that impaired mitochondrial biogenesis and decreased activity of respiratory chain enzymatic complexes was present in SCAT and PM of obese and diabetic patients. VLCD improved metabolic parameters and ameliorated mitochondrial oxidative function in peripheral blood elements of T2DM subjects but had only minor and inconsistent effect on mitochondrial gene mRNA expression in SCAT and PM.
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Affiliation(s)
- M Urbanová
- Institute of Rheumatology, Prague, Czech Republic, Centre for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
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18
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Gueguen A, Jardel C, Polivka M, Tan SV, Gray F, Vignal C, Lombès A, Gout O, Bostock H. Nerve excitability changes related to muscle weakness in chronic progressive external ophthalmoplegia. Clin Neurophysiol 2017; 128:1258-1263. [PMID: 28535487 DOI: 10.1016/j.clinph.2017.04.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Revised: 03/25/2017] [Accepted: 04/14/2017] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To explore potential spreading to peripheral nerves of the mitochondrial dysfunction in chronic progressive external ophthalmoplegia (CPEO) by assessing axonal excitability. METHODS CPEO patients (n=13) with large size deletion of mitochondrial DNA and matching healthy controls (n=22) were included in a case-control study. Muscle strength was quantified using MRC sum-score and used to define two groups of patients: CPEO-weak and CPEO-normal (normal strength). Nerve excitability properties of median motor axons were assessed with the TROND protocol and changes interpreted with the aid of a model. RESULTS Alterations of nerve excitability strongly correlated with scores of muscle strength. CPEO-weak displayed abnormal nerve excitability compared to CPEO-normal and healthy controls, with increased superexcitability and responses to hyperpolarizing current. Modeling indicated that the CPEO-weak recordings were best explained by an increase in the 'Barrett-Barrett' conductance across the myelin sheath. CONCLUSION CPEO patients with skeletal weakness presented sub-clinical nerve excitability changes, which were not consistent with axonal membrane depolarization, but suggested Schwann cell involvement. SIGNIFICANCE This study provides new insights into the spreading of large size deletion of mitochondrial DNA to Schwann cells in CPEO patients.
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Affiliation(s)
- Antoine Gueguen
- Department of Neurology, Fondation Ophtalmologique A. de Rothschild, Paris, France
| | - Claude Jardel
- INSERM U1016, Institut Cochin, Paris F-75014, France; Department of Metabolic Biochemistry, AP/HP, Hôpital Pitié-Salpêtrière, Paris F-75651, France
| | - Marc Polivka
- Department of Anatomical Pathology, AP/HP, Hôpital Lariboisière, Paris, France
| | - S Veronica Tan
- Institute of Neurology, University College London, London, United Kingdom
| | - Françoise Gray
- Department of Anatomical Pathology, AP/HP, Hôpital Lariboisière, Paris, France
| | - Catherine Vignal
- Department of Neuro-Ophthalmology, Fondation Ophtalmologique A. de Rothschild, Paris, France
| | - Anne Lombès
- INSERM U1016, Institut Cochin, Paris F-75014, France; Department of Metabolic Biochemistry, AP/HP, Hôpital Pitié-Salpêtrière, Paris F-75651, France
| | - Olivier Gout
- Department of Neurology, Fondation Ophtalmologique A. de Rothschild, Paris, France
| | - Hugh Bostock
- Institute of Neurology, University College London, London, United Kingdom.
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19
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Zaia A, Maponi P, Di Stefano G, Casoli T. Biocomplexity and Fractality in the Search of Biomarkers of Aging and Pathology: Focus on Mitochondrial DNA and Alzheimer's Disease. Aging Dis 2017; 8:44-56. [PMID: 28197358 PMCID: PMC5291006 DOI: 10.14336/ad.2016.0629] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 06/29/2016] [Indexed: 12/14/2022] Open
Abstract
Alzheimer’s disease (AD) represents one major health concern for our growing elderly population. It accounts for increasing impairment of cognitive capacity followed by loss of executive function in late stage. AD pathogenesis is multifaceted and difficult to pinpoint, and understanding AD etiology will be critical to effectively diagnose and treat the disease. An interesting hypothesis concerning AD development postulates a cause-effect relationship between accumulation of mitochondrial DNA (mtDNA) mutations and neurodegenerative changes associated with this pathology. Here we propose a computerized method for an easy and fast mtDNA mutations-based characterization of AD. The method has been built taking into account the complexity of living being and fractal properties of many anatomic and physiologic structures, including mtDNA. Dealing with mtDNA mutations as gaps in the nucleotide sequence, fractal lacunarity appears a suitable tool to differentiate between aging and AD. Therefore, Chaos Game Representation method has been used to display DNA fractal properties after adapting the algorithm to visualize also heteroplasmic mutations. Parameter β from our fractal lacunarity method, based on hyperbola model function, has been measured to quantitatively characterize AD on the basis of mtDNA mutations. Results from this pilot study to develop the method show that fractal lacunarity parameter β of mtDNA is statistically different in AD patients when compared to age-matched controls. Fractal lacunarity analysis represents a useful tool to analyze mtDNA mutations. Lacunarity parameter β is able to characterize individual mutation profile of mitochondrial genome and appears a promising index to discriminate between AD and aging.
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Affiliation(s)
- Annamaria Zaia
- 1Laboratory of Bioinformatics, Bioengineering and Domotics, Italian National Research Center on Aging - INRCA, via Birarelli 8, 60121 Ancona, Italy
| | - Pierluigi Maponi
- 2School of Science and Technology, University of Camerino, via Madonna delle Carceri 9, 62032 Camerino (MC), Italy
| | - Giuseppina Di Stefano
- 3Research, Innovation and Technology Transfer Office, Italian National Research Center on Aging - INRCA, via Birarelli 8, 60121 Ancona, Italy
| | - Tiziana Casoli
- 4Scientific and Technological Area, Italian National Research Center on Aging - INRCA, via Birarelli 8, 60121 Ancona, Italy
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20
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Monteiro-Cardoso VF, Castro M, Oliveira MM, Moreira PI, Peixoto F, Videira RA. Age-dependent biochemical dysfunction in skeletal muscle of triple-transgenic mouse model of Alzheimer`s disease. Curr Alzheimer Res 2015; 12:100-15. [PMID: 25654504 PMCID: PMC4428479 DOI: 10.2174/1567205012666150204124852] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 09/21/2014] [Accepted: 10/09/2014] [Indexed: 12/25/2022]
Abstract
The emergence of Alzheimer`s disease as a systemic pathology shifted the research paradigm toward a better
understanding of the molecular basis of the disease considering the pathophysiological changes in both brain and peripheral
tissues. In the present study, we evaluated the impact of disease progression on physiological relevant features of
skeletal muscle obtained from 3, 6 and 12 month-old 3xTg-AD mice, a model of Alzheimer`s disease, and respective agematched
nonTg mice. Our results showed that skeletal muscle functionality is already affected in 3-month-old 3xTg-AD
mice as evidenced by deficient acetylcholinesterase and catalase activities as well as by alterations in fatty acid composition
of mitochondrial membranes. Additionally, an age-dependent accumulation of amyloid-β1-40 peptide occurred in
skeletal muscle of 3xTg-AD mice, an effect that preceded bioenergetics mitochondrial dysfunction, which was only detected
at 12 months of age, characterized by decreased respiratory control ratio and ADP/O index and by an impairment of
complex I activity. HPLC-MS/MS analyses revealed significant changes in phospholipid composition of skeletal muscle
tissues from 3xTg-AD mice with 12 months of age when compared with age-matched nonTg mice. Increased levels of
lyso-phosphatidylcholine associated with a decrease of phosphatidylcholine molecular species containing arachidonic acid
were detected in 3xTg-AD mice, indicating an enhancement of phospholipase A2 activity and skeletal muscle inflammation.
Additionally, a decrease of phosphatidylethanolamine plasmalogens content and an increase in phosphatidylinositol
levels was observed in 3xTg-AD mice when compared with age-matched nonTg mice. Altogether, these observations
suggest that the skeletal muscle of 3xTg-AD mice are more prone to oxidative and inflammatory events.
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Affiliation(s)
| | | | | | | | | | - Romeu A Videira
- Chemistry Center - Vila Real (CQ-VR), Chemistry Department, School of Life and Environmental Sciences, University of Tras-os-Montes e Alto Douro, UTAD, P.O. Box 1013; 5001-801 Vila Real, Portugal.
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21
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Korzeniewski B. Effects of OXPHOS complex deficiencies and ESA dysfunction in working intact skeletal muscle: implications for mitochondrial myopathies. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:1310-9. [DOI: 10.1016/j.bbabio.2015.07.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 07/14/2015] [Accepted: 07/15/2015] [Indexed: 10/23/2022]
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22
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Fröhlich C, Zschiebsch K, Gröger V, Paarmann K, Steffen J, Thurm C, Schropp EM, Brüning T, Gellerich F, Radloff M, Schwabe R, Lachmann I, Krohn M, Ibrahim S, Pahnke J. Activation of Mitochondrial Complex II-Dependent Respiration Is Beneficial for α-Synucleinopathies. Mol Neurobiol 2015; 53:4728-44. [PMID: 26319560 PMCID: PMC4965489 DOI: 10.1007/s12035-015-9399-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 08/17/2015] [Indexed: 02/06/2023]
Abstract
Parkinson’s disease and dementia with Lewy bodies are major challenges in research and clinical medicine world-wide and contribute to the most common neurodegenerative disorders. Previously, specific mitochondrial polymorphisms have been found to enhance clearance of amyloid-β from the brain of APP-transgenic mice leading to beneficial clinical outcome. It has been discussed whether specific mitochondrial alterations contribute to disease progression or even prevent toxic peptide deposition, as seen in many neurodegenerative diseases. Here, we investigated α-synuclein-transgenic C57BL/6J mice with the A30P mutation, and a novel A30P C57BL/6J mouse model with three mitochondrial DNA polymorphisms in the ND3, COX3 and mtRNAArg genes, as found in the inbred NOD/LtJ mouse strain. We were able to detect that the new model has increased mitochondrial complex II-respiration which occurs in parallel to neuronal loss and improved motor performance, although it exhibits higher amounts of high molecular weight species of α-synuclein. High molecular weight aggregates of different peptides are controversially discussed in the light of neurodegeneration. A favourable hypothesis states that high molecular weight species are protective and of minor importance for the pathogenesis of neurodegenerative disorders as compared to the extreme neurotoxic monomers and oligomers. Summarising, our results point to a potentially protective and beneficial effect of specific mitochondrial polymorphisms which cause improved mitochondrial complex II-respiration in α-synucleinopathies, an effect that could be exploited further for pharmaceutical interventions.
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Affiliation(s)
- Christina Fröhlich
- Department of Neurology, Neurodegeneration Research Lab (NRL), University of Magdeburg, Magdeburg, Germany
| | - Katja Zschiebsch
- Department of Neurology, Neurodegeneration Research Lab (NRL), University of Magdeburg, Magdeburg, Germany.,University of Frankfurt, Institute of Clinical Pharmacology/ZAFES, Frankfurt, Germany
| | - Victoria Gröger
- Department of Neurology, Neurodegeneration Research Lab (NRL), University of Magdeburg, Magdeburg, Germany.,Fraunhofer Institute for Cell Therapy and Immunology (IZI), Halle, Germany
| | - Kristin Paarmann
- Department of Pathology (PAT), Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo (UiO) and Oslo University Hospital (OUS), Postboks 4950 Nydalen, 0424, Oslo, Norway.,Department of Neurology, Neurodegeneration Research Lab (NRL), University of Magdeburg, Magdeburg, Germany.,LIED, University of Lübeck (UzL), Lübeck, Germany
| | - Johannes Steffen
- Department of Pathology (PAT), Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo (UiO) and Oslo University Hospital (OUS), Postboks 4950 Nydalen, 0424, Oslo, Norway.,Department of Neurology, Neurodegeneration Research Lab (NRL), University of Magdeburg, Magdeburg, Germany.,LIED, University of Lübeck (UzL), Lübeck, Germany
| | - Christoph Thurm
- Department of Neurology, Neurodegeneration Research Lab (NRL), University of Magdeburg, Magdeburg, Germany
| | - Eva-Maria Schropp
- Department of Neurology, Neurodegeneration Research Lab (NRL), University of Magdeburg, Magdeburg, Germany
| | - Thomas Brüning
- Department of Pathology (PAT), Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo (UiO) and Oslo University Hospital (OUS), Postboks 4950 Nydalen, 0424, Oslo, Norway.,Department of Neurology, Neurodegeneration Research Lab (NRL), University of Magdeburg, Magdeburg, Germany
| | - Frank Gellerich
- Department of Neurology, University of Magdeburg/Leibniz Institut for Neurobiology, Magdeburg, Germany
| | - Martin Radloff
- Institute for Mathematical Stochastics, University of Magdeburg, Magdeburg, Germany
| | - Rainer Schwabe
- Institute for Mathematical Stochastics, University of Magdeburg, Magdeburg, Germany
| | | | - Markus Krohn
- Department of Pathology (PAT), Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo (UiO) and Oslo University Hospital (OUS), Postboks 4950 Nydalen, 0424, Oslo, Norway.,Department of Neurology, Neurodegeneration Research Lab (NRL), University of Magdeburg, Magdeburg, Germany
| | | | - Jens Pahnke
- Department of Pathology (PAT), Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo (UiO) and Oslo University Hospital (OUS), Postboks 4950 Nydalen, 0424, Oslo, Norway. .,Department of Neurology, Neurodegeneration Research Lab (NRL), University of Magdeburg, Magdeburg, Germany. .,LIED, University of Lübeck (UzL), Lübeck, Germany. .,Department of Bioorganic Chemistry, Leibniz-Institute of Plant Biochemistry (IPB), Halle, Germany.
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23
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Zimmermann C, Kalepu R, Ponfick M, Reichel H, Cakir B, Zierz S, Gdynia HJ, Kassubek J, Ludolph AC, Rosenbohm A. Histological characterization and biochemical analysis of paraspinal muscles in neuromuscularly healthy subjects. Muscle Nerve 2015; 52:45-54. [PMID: 25307884 DOI: 10.1002/mus.24490] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/09/2014] [Indexed: 01/07/2023]
Abstract
INTRODUCTION There are no generally accepted histopathological reference values in paraspinal skeletal muscle biopsies. METHODS We examined multifidii muscle biopsies from 20 neuromuscularly healthy subjects using routine histological stains and biochemical analyses of respiratory chain enzymes. RESULTS Staining showed incomplete myopathic features, such as increased variability in fiber size, type 1 hypertrophy, rounded fiber shape, endomysial fibrosis, and replacement by adipose tissue. Acid phosphatase reaction was positive in up to 35% of the selected muscle fibers. Mitochondrial changes were obvious but revealed no selective age dependence. Reduced complex I, cytochrome c oxidase (COX), and citrate synthase (CS) could be observed. CONCLUSIONS Because the increased variability in morphological details can easily be misinterpreted as myopathic changes, analysis of paraspinal muscles should take into consideration that incomplete myopathic features and reduced oxidative enzyme activities for complex I, COX, and CS are normal variations at this location.
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Affiliation(s)
- Claudia Zimmermann
- Department of Neurology, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany
| | - Rajakiran Kalepu
- Department of Neurology, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany
| | - Matthias Ponfick
- Department of Neurology, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany
| | - Heiko Reichel
- Department of Orthopaedic Surgery, University of Ulm, Ulm, Germany
| | - Balkan Cakir
- Department of Orthopaedic Surgery, University of Ulm, Ulm, Germany
| | - Stephan Zierz
- Department of Neurology, University of Halle, Halle (Saale), Germany
| | - Hans-Jürgen Gdynia
- Department of Neurology, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany
| | - Jan Kassubek
- Department of Neurology, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany
| | - Albert C Ludolph
- Department of Neurology, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany
| | - Angela Rosenbohm
- Department of Neurology, University of Ulm, Oberer Eselsberg 45, 89081, Ulm, Germany
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24
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Lehmann D, Schubert K, Joshi PR, Hardy SA, Tuppen HAL, Baty K, Blakely EL, Bamberg C, Zierz S, Deschauer M, Taylor RW. Pathogenic mitochondrial mt-tRNA(Ala) variants are uniquely associated with isolated myopathy. Eur J Hum Genet 2015; 23:1735-8. [PMID: 25873012 PMCID: PMC4519577 DOI: 10.1038/ejhg.2015.73] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 03/12/2015] [Indexed: 11/09/2022] Open
Abstract
Pathogenic mitochondrial DNA (mtDNA) point mutations are associated with a wide range of clinical phenotypes, often involving multiple organ systems. We report two patients with isolated myopathy owing to novel mt-tRNA(Ala) variants. Muscle biopsy revealed extensive histopathological findings including cytochrome c oxidase (COX)-deficient fibres. Pyrosequencing confirmed mtDNA heteroplasmy for both mutations (m.5631G>A and m.5610G>A) whilst single-muscle fibre segregation studies (revealing statistically significant higher mutation loads in COX-deficient fibres than in COX-positive fibres), hierarchical mutation segregation within patient tissues and decreased steady-state mt-tRNA(Ala) levels all provide compelling evidence of pathogenicity. Interestingly, both patients showed very high-mutation levels in all tissues, inferring that the threshold for impairment of oxidative phosphorylation, as evidenced by COX deficiency, appears to be extremely high for these mt-tRNA(Ala) variants. Previously described mt-tRNA(Ala) mutations are also associated with a pure myopathic phenotype and demonstrate very high mtDNA heteroplasmy thresholds, inferring at least some genotype:phenotype correlation for mutations within this particular mt-tRNA gene.
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Affiliation(s)
- Diana Lehmann
- Department of Neurology, University of Halle-Wittenberg, Halle (Saale), Germany
| | - Kathrin Schubert
- Department of Neurology, University of Halle-Wittenberg, Halle (Saale), Germany
| | - Pushpa R Joshi
- Department of Neurology, University of Halle-Wittenberg, Halle (Saale), Germany
| | - Steven A Hardy
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, UK
| | - Helen A L Tuppen
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, UK
| | - Karen Baty
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, UK
| | - Emma L Blakely
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, UK
| | | | - Stephan Zierz
- Department of Neurology, University of Halle-Wittenberg, Halle (Saale), Germany
| | - Marcus Deschauer
- Department of Neurology, University of Halle-Wittenberg, Halle (Saale), Germany
| | - Robert W Taylor
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, UK
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25
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Kodaira M, Hatakeyama H, Yuasa S, Seki T, Egashira T, Tohyama S, Kuroda Y, Tanaka A, Okata S, Hashimoto H, Kusumoto D, Kunitomi A, Takei M, Kashimura S, Suzuki T, Yozu G, Shimojima M, Motoda C, Hayashiji N, Saito Y, Goto YI, Fukuda K. Impaired respiratory function in MELAS-induced pluripotent stem cells with high heteroplasmy levels. FEBS Open Bio 2015; 5:219-25. [PMID: 25853038 PMCID: PMC4383791 DOI: 10.1016/j.fob.2015.03.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/18/2015] [Accepted: 03/18/2015] [Indexed: 01/19/2023] Open
Abstract
We modeled the mitochondrial disease MELAS by generating patient-specific iPS cells. MELAS-iPS cells show a wide variety of heteroplasmy levels. MELAS-iPS cells with high heteroplasmy levels showed impaired complex I activity.
Mitochondrial diseases are heterogeneous disorders, caused by mitochondrial dysfunction. Mitochondria are not regulated solely by nuclear genomic DNA but by mitochondrial DNA. It is difficult to develop effective therapies for mitochondrial disease because of the lack of mitochondrial disease models. Mitochondrial myopathy, encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) is one of the major mitochondrial diseases. The aim of this study was to generate MELAS-specific induced pluripotent stem cells (iPSCs) and to demonstrate that MELAS-iPSCs can be models for mitochondrial disease. We successfully established iPSCs from the primary MELAS-fibroblasts carrying 77.7% of m.3243A>G heteroplasmy. MELAS-iPSC lines ranged from 3.6% to 99.4% of m.3243A>G heteroplasmy levels. The enzymatic activities of mitochondrial respiratory complexes indicated that MELAS-iPSC-derived fibroblasts with high heteroplasmy levels showed a deficiency of complex I activity but MELAS-iPSC-derived fibroblasts with low heteroplasmy levels showed normal complex I activity. Our data indicate that MELAS-iPSCs can be models for MELAS but we should carefully select MELAS-iPSCs with appropriate heteroplasmy levels and respiratory functions for mitochondrial disease modeling.
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Key Words
- Disease modeling
- EB, embryoid body
- ES, embryonic stem
- KSR, Knock-out Serum Replacement
- MEF, mouse embryonic fibroblast
- MELAS
- MELAS, mitochondrial myopathy, encephalomyopathy, lactic acidosis, and stroke-like episodes
- Mitochondrial disease
- OXPHOS, oxidative phosphorylation system
- bFGF, basic fibroblast growth factor
- iPS cell
- iPSCs, induced pluripotent stem cells
- mtDNA, mitochondrial DNA
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Affiliation(s)
- Masaki Kodaira
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Hideyuki Hatakeyama
- Department of Mental Retardation and Birth Defect Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo, Japan
| | - Shinsuke Yuasa
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
- Corresponding author at: Department of Cardiology, Keio University School of Medicine, 35-Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Tel.: +81 3 5363 3373; fax: +81 3 5363 3875.
| | - Tomohisa Seki
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Toru Egashira
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Shugo Tohyama
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Yusuke Kuroda
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Atsushi Tanaka
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Shinichiro Okata
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Hisayuki Hashimoto
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Dai Kusumoto
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Akira Kunitomi
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Makoto Takei
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Shin Kashimura
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Tomoyuki Suzuki
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Gakuto Yozu
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Masaya Shimojima
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Chikaaki Motoda
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Nozomi Hayashiji
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Yuki Saito
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
| | - Yu-ichi Goto
- Department of Mental Retardation and Birth Defect Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo, Japan
| | - Keiichi Fukuda
- Department of Cardiology, Keio University School of Medicine, Tokyo, Japan
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26
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Joshi PR, Vetterke M, Hauburger A, Tacik P, Stoltenburg G, Hanisch F. Functional relevance of mitochondrial abnormalities in sporadic inclusion body myositis. J Clin Neurosci 2014; 21:1959-63. [PMID: 25311418 DOI: 10.1016/j.jocn.2014.05.051] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 05/21/2014] [Accepted: 05/30/2014] [Indexed: 10/24/2022]
Abstract
Cytochrome c oxidase (COX)-deficient fibers and multiple mitochondrial DNA (mtDNA) deletions are frequent findings in sporadic inclusion body myositis (s-IBM). However, the functional impact of these defects is not known. We investigated oxygen desaturation during exercise using the forearm exercise test, accumulation of lactate during exercise using a cycle ergometry test and mitochondrial changes (COX-deficient fibers, biochemical activities of respiratory chain complexes, multiple mtDNA deletions by long-range polymerase chain reaction) in 10 patients with s-IBM and compared the findings with age and sex-matched normal and diseased controls (without mitochondrial disorders) as well as patients with mitochondrial disorder due to nuclear gene defects resulting in multiple mtDNA deletions (MITO group). The mean age of the s-IBM patients was 68.2 ± 5.7 years (range: 56-75). Patients with s-IBM had statistically significantly reduced oxygen desaturation (ΔsO2) during the handgrip exercise (p<0.05) and elevated peak serum lactate levels during cycle ergometry compared to normal controls (p<0.05). The percentage of COX-deficient fibers in s-IBM and MITO patients was significantly increased compared to normal controls (p<0.01). Five out of nine s-IBM patients had multiple mtDNA deletions. Thirty-three percent of s-IBM patients showed an increased citrate synthase content and decreased activities of complex IV (COX). The biochemical pattern of respiratory chain complexes in patients with s-IBM and MITO was similar. Histopathological analysis showed similar changes in s-IBM and MITO due to nuclear gene defects. Functional tests reflecting mitochondrial impairment suggest a contribution of mitochondrial defects to disease-related symptoms such as fatigue and exertion-induced symptoms.
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Affiliation(s)
- Pushpa Raj Joshi
- Department of Neurology, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Str. 40, 06120 Halle (Saale), Germany.
| | - Mirjam Vetterke
- Department of Neurology, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Str. 40, 06120 Halle (Saale), Germany
| | - Anja Hauburger
- Department of Neurology, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Str. 40, 06120 Halle (Saale), Germany
| | - Pawel Tacik
- Department of Neurology, Hannover Medical School, Hannover, Germany
| | - Gisela Stoltenburg
- Department of Neurology, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Str. 40, 06120 Halle (Saale), Germany; Institute of Cell Biology and Neurobiology, Charité, Universitätsmedizin Berlin, Berlin, Germany
| | - Frank Hanisch
- Department of Neurology, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Str. 40, 06120 Halle (Saale), Germany
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27
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Lehmann D, Schubert K, Joshi PR, Baty K, Blakely EL, Zierz S, Taylor RW, Deschauer M. A novel m.7539C>T point mutation in the mt-tRNA(Asp) gene associated with multisystemic mitochondrial disease. Neuromuscul Disord 2014; 25:81-4. [PMID: 25447692 PMCID: PMC4317191 DOI: 10.1016/j.nmd.2014.09.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 09/03/2014] [Accepted: 09/17/2014] [Indexed: 11/18/2022]
Abstract
Mitochondrial transfer RNA (mt-tRNA) mutations are the commonest sub-type of mitochondrial (mtDNA) mutations associated with human disease. We report a patient with multisytemic disease characterised by myopathy, spinal ataxia, sensorineural hearing loss, cataract and cognitive impairment in whom a novel m.7539C>T mt-tRNA(Asp) transition was identified. Muscle biopsy revealed extensive histopathological findings including cytochrome c oxidase (COX)-deficient fibres. Pyrosequencing confirmed mtDNA heteroplasmy for the mutation whilst single muscle fibre segregation studies revealed statistically significant higher mutation loads in COX-deficient fibres than in COX-positive fibres. Absence from control databases, hierarchical mt-tRNA mutation segregation within tissues, and occurrence at conserved sequence positions, further confirm this novel mt-tRNA mutation to be pathogenic. To date only three mt-tRNA(Asp) gene mutations have been described with clear evidence of pathogenicity. The novel m.7539C>T mt-tRNA(Asp) gene mutation extends the spectrum of pathogenic mutations in this gene, further supporting the notion that mt-tRNA(Asp) gene mutations are associated with multisystemic disease presentations.
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Affiliation(s)
- Diana Lehmann
- Department of Neurology, University of Halle-Wittenberg, Ernst-Grube-Str. 40, Halle/Saale 06097, Germany
| | - Kathrin Schubert
- Department of Neurology, University of Halle-Wittenberg, Ernst-Grube-Str. 40, Halle/Saale 06097, Germany
| | - Pushpa R Joshi
- Department of Neurology, University of Halle-Wittenberg, Ernst-Grube-Str. 40, Halle/Saale 06097, Germany
| | - Karen Baty
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, UK
| | - Emma L Blakely
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, UK
| | - Stephan Zierz
- Department of Neurology, University of Halle-Wittenberg, Ernst-Grube-Str. 40, Halle/Saale 06097, Germany
| | - Robert W Taylor
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, UK
| | - Marcus Deschauer
- Department of Neurology, University of Halle-Wittenberg, Ernst-Grube-Str. 40, Halle/Saale 06097, Germany.
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28
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6-Hydroxydopamine impairs mitochondrial function in the rat model of Parkinson's disease: respirometric, histological, and behavioral analyses. J Neural Transm (Vienna) 2014; 121:1245-57. [PMID: 24627045 DOI: 10.1007/s00702-014-1185-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 02/23/2014] [Indexed: 10/25/2022]
Abstract
Mitochondrial defects have been shown to be associated with the pathogenesis of Parkinson's disease (PD). Yet, experience in PD research linking mitochondrial dysfunction, e.g., deregulation of oxidative phosphorylation, with neuronal degeneration and behavioral changes is rather limited. Using the 6-hydroxydopamine (6-OHDA) rat model of PD, we have investigated the potential role of mitochondria in dopaminergic neuronal cell death in the substantia nigra pars compacta by high-resolution respirometry. Mitochondrial function was correlated with the time course of disease-related motor behavior asymmetry and dopaminergic neuronal cell loss, respectively. Unilateral 6-OHDA injections (>2.5 μg/2 μl) into the median forebrain bundle induced an impairment of oxidative phosphorylation due to a decrease in complex I activity. This was indicated by increased flux control coefficient. During the period of days 2-21, a progressive decrease in respiratory control ratio of up to -58 % was observed in the lesioned compared to the non-lesioned substantia nigra of the same animals. This decrease was associated with a marked uncoupling of oxidative phosphorylation. Mitochondrial dysfunction, motor behavior asymmetry, and dopaminergic neuronal cell loss correlated with dosage (1.25-5 μg/2 μl). We conclude that high-resolution respirometry may allow the detection of distinct mitochondrial dysfunction as a suitable surrogate marker for the preclinical assessment of potential neuroprotective strategies in the 6-OHDA model of PD.
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29
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Grady JP, Campbell G, Ratnaike T, Blakely EL, Falkous G, Nesbitt V, Schaefer AM, McNally RJ, Gorman GS, Taylor RW, Turnbull DM, McFarland R. Disease progression in patients with single, large-scale mitochondrial DNA deletions. Brain 2013; 137:323-34. [PMID: 24277717 PMCID: PMC3914470 DOI: 10.1093/brain/awt321] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Single, large-scale deletions of mitochondrial DNA are a common cause of mitochondrial disease and cause a broad phenotypic spectrum ranging from mild myopathy to devastating multi-system syndromes such as Kearns-Sayre syndrome. Studies to date have been inconsistent on the value of putative predictors of clinical phenotype and disease progression such as mutation load and the size or location of the deletion. Using a cohort of 87 patients with single, large-scale mitochondrial DNA deletions we demonstrate that a variety of outcome measures such as COX-deficient fibre density, age-at-onset of symptoms and progression of disease burden, as measured by the Newcastle Mitochondrial Disease Adult Scale, are significantly (P < 0.05) correlated with the size of the deletion, the deletion heteroplasmy level in skeletal muscle, and the location of the deletion within the genome. We validate these findings with re-analysis of 256 cases from published data and clarify the previously conflicting information of the value of these predictors, identifying that multiple regression analysis is necessary to understand the effect of these interrelated predictors. Furthermore, we have used mixed modelling techniques to model the progression of disease according to these predictors, allowing a better understanding of the progression over time of this strikingly variable disease. In this way we have developed a new paradigm in clinical mitochondrial disease assessment and management that sidesteps the perennial difficulty of ascribing a discrete clinical phenotype to a broad multi-dimensional and progressive spectrum of disease, establishing a framework to allow better understanding of disease progression.
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Affiliation(s)
- John P Grady
- 1 Wellcome Trust Centre for Mitochondrial Research, Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, UK
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30
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Oxygen glucose deprivation causes mitochondrial dysfunction in cultivated rat hippocampal slices: Protective effects of CsA, its immunosuppressive congener [D-Ser]8CsA, the novel non-immunosuppressive cyclosporin derivative Cs9, and the NMDA receptor antagonist MK 801. Mitochondrion 2013; 13:539-47. [DOI: 10.1016/j.mito.2012.07.110] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 07/11/2012] [Accepted: 07/15/2012] [Indexed: 02/06/2023]
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31
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Deficiency of the complex I of the mitochondrial respiratory chain but improved adenylate control over succinate-dependent respiration are human gastric cancer-specific phenomena. Mol Cell Biochem 2012; 370:69-78. [PMID: 22821176 DOI: 10.1007/s11010-012-1399-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 07/07/2012] [Indexed: 12/13/2022]
Abstract
The purpose of study was to comparatively characterize the oxidative phosphorylation (OXPHOS) and function of respiratory chain in mitochondria in human gastric corpus mucosa undergoing transition from normal to cancer states and in human gastric cancer cell lines, MKN28 and MKN45. The tissue samples taken by endobiopsy and the cells were permeabilized by saponin treatment to assess mitochondrial function in situ by high-resolution oxygraphy. Compared to the control group of endobiopsy samples, the maximal capacity of OXPHOS in the cancer group was almost twice lower. The respiratory chain complex I-dependent respiration, normalized to complex II-dependent respiration, was reduced that suggests deficiency of complex I, but the respiratory control by ADP in the presence of succinate was increased. Similar changes were observed also in mucosa adjacent to cancer tissue. The respiratory capacity of MKN45 cells was higher than that of MKN28 cells, but both types of cells exhibited a deficiency of complex I of the respiratory chain which appears to be an intrinsic property of the cancer cells. In conclusion, human gastric cancer is associated with decreased respiratory capacity, deficiency of the respiratory complex I of mitochondria, and improved coupling of succinate oxidation to phosphorylation in tumor tissue and adjacent atrophic mucosa. Detection of these changes in endobiopsy samples may be of diagnostic value.
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32
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Mueller EE, Mayr JA, Zimmermann FA, Feichtinger RG, Stanger O, Sperl W, Kofler B. Reduction of nuclear encoded enzymes of mitochondrial energy metabolism in cells devoid of mitochondrial DNA. Biochem Biophys Res Commun 2011; 417:1052-7. [PMID: 22222373 DOI: 10.1016/j.bbrc.2011.12.093] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Accepted: 12/19/2011] [Indexed: 11/29/2022]
Abstract
Mitochondrial DNA (mtDNA) depletion syndromes are generally associated with reduced activities of oxidative phosphorylation (OXPHOS) enzymes that contain subunits encoded by mtDNA. Conversely, entirely nuclear encoded mitochondrial enzymes in these syndromes, such as the tricarboxylic acid cycle enzyme citrate synthase (CS) and OXPHOS complex II, usually exhibit normal or compensatory enhanced activities. Here we report that a human cell line devoid of mtDNA (HEK293 ρ(0) cells) has diminished activities of both complex II and CS. This finding indicates the existence of a feedback mechanism in ρ(0) cells that downregulates the expression of entirely nuclear encoded components of mitochondrial energy metabolism.
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Affiliation(s)
- Edith E Mueller
- Research Program for Receptor Biochemistry and Tumor Metabolism, Department of Pediatrics, Salzburg, Austria.
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33
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Ross JM. Visualization of mitochondrial respiratory function using cytochrome c oxidase/succinate dehydrogenase (COX/SDH) double-labeling histochemistry. J Vis Exp 2011:e3266. [PMID: 22143245 DOI: 10.3791/3266] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Mitochondrial DNA (mtDNA) defects are an important cause of disease and may underlie aging and aging-related alterations (1,2). The mitochondrial theory of aging suggests a role for mtDNA mutations, which can alter bioenergetics homeostasis and cellular function, in the aging process (3). A wealth of evidence has been compiled in support of this theory (1,4), an example being the mtDNA mutator mouse (5); however, the precise role of mtDNA damage in aging is not entirely understood (6,7). Observing the activity of respiratory enzymes is a straightforward approach for investigating mitochondrial dysfunction. Complex IV, or cytochrome c oxidase (COX), is essential for mitochondrial function. The catalytic subunits of COX are encoded by mtDNA and are essential for assembly of the complex (Figure 1). Thus, proper synthesis and function are largely based on mtDNA integrity (2). Although other respiratory complexes could be investigated, Complexes IV and II are the most amenable to histochemical examination (8,9). Complex II, or succinate dehydrogenase (SDH), is entirely encoded by nuclear DNA (Figure 1), and its activity is typically not affected by impaired mtDNA, although an increase might indicate mitochondrial biogenesis (10-12). The impaired mtDNA observed in mitochondrial diseases, aging, and age-related diseases often leads to the presence of cells with low or absent COX activity (2,12-14). Although COX and SDH activities can be investigated individually, the sequential double-labeling method (15,16) has proved to be advantageous in locating cells with mitochondrial dysfunction (12,17-21). Many of the optimal constitutions of the assay have been determined, such as substrate concentration, electron acceptors/donors, intermediate electron carriers, influence of pH, and reaction time (9,22,23). 3,3'-diaminobenzidine (DAB) is an effective and reliable electron donor (22). In cells with functioning COX, the brown indamine polymer product will localize in mitochondrial cristae and saturate cells (22). Those cells with dysfunctional COX will therefore not be saturated by the DAB product, allowing for the visualization of SDH activity by reduction of nitroblue tetrazolium (NBT), an electron acceptor, to a blue formazan end product (9,24). Cytochrome c and sodium succinate substrates are added to normalize endogenous levels between control and diseased/mutant tissues (9). Catalase is added as a precaution to avoid possible contaminating reactions from peroxidase activity (9,22). Phenazine methosulfate (PMS), an intermediate electron carrier, is used in conjunction with sodium azide, a respiratory chain inhibitor, to increase the formation of the final reaction products (9,25). Despite this information, some critical details affecting the result of this seemly straightforward assay, in addition to specificity controls and advances in the technique, have not yet been presented.
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Affiliation(s)
- Jaime M Ross
- Department of Neuroscience, Karolinska Institutet
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34
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Li L, Mühlfeld C, Niemann B, Pan R, Li R, Hilfiker-Kleiner D, Chen Y, Rohrbach S. Mitochondrial biogenesis and PGC-1α deacetylation by chronic treadmill exercise: differential response in cardiac and skeletal muscle. Basic Res Cardiol 2011; 106:1221-34. [PMID: 21874557 DOI: 10.1007/s00395-011-0213-9] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 07/15/2011] [Accepted: 08/03/2011] [Indexed: 11/26/2022]
Abstract
Posttranslational modifications of the transcriptional coactivator PGC-1α by the deacetylase SIRT1 and the kinase AMPK are involved in exercise-induced mitochondrial biogenesis in skeletal muscle. However, similar investigations have not been performed in the left ventricle (LV). Here, we tested whether treadmill training (12 weeks) modifies PGC-1α and mitochondrial biogenesis in gastrocnemius muscle and LV of C57BL/6 J wild-type mice and IL-6-deficient mice with a reported impairment in muscular AMPK activation similarly. Physical activity lowered the plasma insulin and glucose in both mouse strains, suggesting improved insulin sensitivity. The gastrocnemius muscle of IL-6-deficient mice showed reduced mitochondrial respiration and enzyme activity, which was partially normalized after training. Chronic exercise enhanced the mitochondrial biogenesis in gastrocnemius muscle as indicated by increased mRNA or protein expression of primary mitochondrial transcripts, higher mtDNA content and increased citrate synthase activity. Parallel to these changes, we observed AMPK activation, SIRT1 induction and PGC-1α deacetylation. Chronic treadmill training resulted in a mild cardiac hypertrophy in both mouse strains. However, none of these changes observed in skeletal muscle were detected in the LV (both mouse strains) with the exception of AMPK activation and a mildly increased succinate-dependent respiration. Thus, chronic endurance training induces a sustained mitochondrial biogenic response in mouse gastrocnemius muscle but not in the LV. Although AMPK activation occurs in both muscular organs, the absence of SIRT1-dependent PGC-1α deacetylation may be responsible for this significant difference. AMPK activation by IL-6 appears to be dispensable for the mitochondrial biogenic responses to chronic treadmill exercise.
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MESH Headings
- Acetylation
- Animals
- Blood Glucose
- Blotting, Western
- Enzyme-Linked Immunosorbent Assay
- Heart Ventricles/metabolism
- Heart Ventricles/ultrastructure
- Immunoprecipitation
- Insulin/blood
- Interleukin-6/deficiency
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Microscopy, Electron, Transmission
- Mitochondria, Heart/metabolism
- Mitochondria, Heart/ultrastructure
- Mitochondria, Muscle/metabolism
- Mitochondria, Muscle/ultrastructure
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/ultrastructure
- Myocardium/metabolism
- Myocardium/ultrastructure
- Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
- Physical Conditioning, Animal/physiology
- RNA, Messenger/analysis
- Real-Time Polymerase Chain Reaction
- Reverse Transcriptase Polymerase Chain Reaction
- Sirtuin 1
- Trans-Activators/metabolism
- Transcription Factors
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Affiliation(s)
- Ling Li
- Institute of Physiology, Justus Liebig University Giessen, Aulweg 129, 35392 Giessen, Germany
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35
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Heidler J, Al-Furoukh N, Kukat C, Salwig I, Ingelmann ME, Seibel P, Krüger M, Holtz J, Wittig I, Braun T, Szibor M. Nitric oxide-associated protein 1 (NOA1) is necessary for oxygen-dependent regulation of mitochondrial respiratory complexes. J Biol Chem 2011; 286:32086-93. [PMID: 21771794 DOI: 10.1074/jbc.m111.221986] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In eukaryotic cells, maintenance of cellular ATP stores depends mainly on mitochondrial oxidative phosphorylation (OXPHOS), which in turn requires sufficient cellular oxygenation. The crucial role of proper oxygenation for cellular viability is reflected by involvement of several mechanisms, which sense hypoxia and regulate activities of respiratory complexes according to available oxygen concentrations. Here, we focus on mouse nitric oxide-associated protein 1 (mNOA1), which has been identified as an important component of the machinery that adjusts OXPHOS activity to oxygen concentrations. mNOA1 is an evolutionary conserved GTP-binding protein that is involved in the regulation of mitochondrial protein translation and respiration. We found that mNOA1 is located mostly in the mitochondrial matrix from where it interacts with several high molecular mass complexes, most notably with the complex IV of the respiratory chain and the prohibitin complex. Knock-down of mNOA1 impaired enzyme activity I+III, resulting in oxidative stress and eventually cell death. mNOA1 is transcriptionally regulated in an oxygen-sensitive manner. We propose that oxygen-dependent regulation of mNOA1 is instrumental to adjusting OXPHOS activity to oxygen availability, thereby controlling mitochondrial metabolism.
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Affiliation(s)
- Juliana Heidler
- Department of Cardiac Development and Remodeling, Max-Planck-Institute for Heart and Lung Research, Ludwigstrasse 43, 61231 Bad Nauheim, Germany
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36
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Giulivi C, Ross-Inta C, Omanska-Klusek A, Napoli E, Sakaguchi D, Barrientos G, Allen PD, Pessah IN. Basal bioenergetic abnormalities in skeletal muscle from ryanodine receptor malignant hyperthermia-susceptible R163C knock-in mice. J Biol Chem 2011; 286:99-113. [PMID: 20978128 PMCID: PMC3013050 DOI: 10.1074/jbc.m110.153247] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 10/13/2010] [Indexed: 12/25/2022] Open
Abstract
Malignant hyperthermia (MH) and central core disease in humans have been associated with mutations in the skeletal ryanodine receptor (RyR1). Heterozygous mice expressing the human MH/central core disease RyR1 R163C mutation exhibit MH when exposed to halothane or heat stress. Considering that many MH symptoms resemble those that could ensue from a mitochondrial dysfunction (e.g. metabolic acidosis and hyperthermia) and that MH-susceptible mice or humans have a higher than normal cytoplasmic Ca(2+) concentration at rest, we evaluated the role of mitochondria in skeletal muscle from R163C compared with wild type mice under basal (untriggered) conditions. R163C skeletal muscle exhibited a significant increase in matrix Ca(2+), increased reactive oxygen species production, lower expression of mitochondrial proteins, and higher mtDNA copy number. These changes, in conjunction with lower myoglobin and glycogen contents, Myh4 and GAPDH transcript levels, GAPDH activity, and lower glucose utilization suggested a switch to a compromised bioenergetic state characterized by both low oxidative phosphorylation and glycolysis. The shift in bioenergetic state was accompanied by a dysregulation of Ca(2+)-responsive signaling pathways regulated by calcineurin and ERK1/2. Chronically elevated resting Ca(2+) in R163C skeletal muscle elicited the maintenance of a fast-twitch fiber program and the development of insulin resistance-like phenotype as part of a metabolic adaptation to the R163C RyR1 mutation.
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Affiliation(s)
- Cecilia Giulivi
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, California 95616, USA.
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Li L, Pan R, Li R, Niemann B, Aurich AC, Chen Y, Rohrbach S. Mitochondrial biogenesis and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) deacetylation by physical activity: intact adipocytokine signaling is required. Diabetes 2011; 60:157-67. [PMID: 20929977 PMCID: PMC3012167 DOI: 10.2337/db10-0331] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE Transcriptional peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) plays a key role in mitochondrial biogenesis and energy metabolism and is suggested to be involved in the exercise-induced increase in mitochondrial content. PGC-1α activity is regulated by posttranslational modifications, among them acetylation or phosphorylation. Accordingly, the deacetylase SIRT1 and the kinase AMPK increase PGC-1α activity. RESEARCH DESIGN AND METHODS We tested whether chronic treadmill exercise or a single exercise session modifies PGC-1α activation and mitochondrial biogenesis differentially in obese ob/ob mice with dysregulated adiponectin/leptin-mediated AMPK activation compared with C57BL/6J wild-type mice. RESULTS Exercise training (12 weeks) induced adiponectin and lowered plasma insulin and glucose, suggesting improved insulin sensitivity in wild-type mice. It enhanced mitochondrial biogenesis in red gastrocnemius muscle, as indicated by increased mRNA expression of transcriptional regulators and primary mitochondrial transcripts, increased mtDNA content, and citrate synthase activity. Parallel to this, we observed AMPK activation, PGC-1α deacetylation, and SIRT1 induction in trained wild-type mice. Although none of these exercise-induced changes were detected in ob/ob mice, comparable effects on mitochondrial respiration were observed. A single exercise session resulted in comparable changes in wild-type mice. These changes remained detectable 6 h after the exercise session but had disappeared after 24 h. Treatment of C2C12 myoblasts with leptin or adiponectin resulted in increased AMPK phosphorylation and PGC-1α deacetylation. CONCLUSIONS Chronic exercise induces mitochondrial biogenesis in wild-type mice, which may require intact AMPK activation by adipocytokines and involve SIRT1-dependent PGC-1α deacetylation. Trained ob/ob mice appear to have partially adapted to reduced mitochondrial biogenesis by AMPK/SIRT1/PGC-1α-independent mechanisms without mtDNA replication.
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Affiliation(s)
- Ling Li
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
| | - Ruping Pan
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
| | - Rong Li
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
| | - Bernd Niemann
- Department of Cardiac and Vascular Surgery, Justus Liebig University Giessen, Giessen, Germany
| | | | - Ying Chen
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
| | - Susanne Rohrbach
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
- Institute of Pathophysiology, Martin Luther University Halle-Wittenberg, Halle, Germany
- Corresponding author: Susanne Rohrbach,
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Wu YT, Wu SB, Lee WY, Wei YH. Mitochondrial respiratory dysfunction-elicited oxidative stress and posttranslational protein modification in mitochondrial diseases. Ann N Y Acad Sci 2010; 1201:147-56. [DOI: 10.1111/j.1749-6632.2010.05631.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Wibrand F, Jeppesen TD, Frederiksen AL, Olsen DB, Duno M, Schwartz M, Vissing J. Limited diagnostic value of enzyme analysis in patients with mitochondrial tRNA mutations. Muscle Nerve 2010; 41:607-13. [PMID: 19941338 DOI: 10.1002/mus.21541] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We evaluated the diagnostic value of respiratory chain (RC) enzyme analysis of muscle in adult patients with mitochondrial myopathy (MM). RC enzyme activity was measured in muscle biopsies from 39 patients who carry either the 3243A>G mutation, other tRNA point mutations, or single, large-scale deletions of mtDNA. Findings were compared with those obtained from asymptomatic relatives with the 3243A>G mutation, myotonic dystrophy patients, and healthy subjects. Plasma lactate concentration, maximal oxygen uptake, and ragged-red fibers/cytochrome c-negative fibers in muscle were also determined. Only 10% of patients with the 3243A>G point mutation had decreased enzyme activity of one or more RC complexes, whereas this was the case for 83% of patients with other point mutations and 62% of patients with deletions. Abnormal muscle histochemistry was found in 65%, 100%, and 85% of patients, respectively, in these three groups. The results indicate that RC enzyme analysis in muscle is not a sensitive test for MM in adults. In these patients, abnormal muscle histochemistry appears to be a better predictor ofMM.
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Affiliation(s)
- Flemming Wibrand
- Department of Clinical Genetics 4061, Rigshospitalet, Blegdamsvej 9, DK-2100 Copenhagen, Denmark.
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Abstract
Mitochondrial encephalomyopathies are clinically and genetically heterogeneous disorders. External ophthalmoplegia is the most frequent symptom. Other frequently involved tissues and organs include the retina, heart, limb muscles, peripheral and central nervous system, inner ear and endocrine system. The diagnosis is based on the finding of elevated serum lactate, the characteristic histopathological changes in the muscle biopsy, and decreased activities of mitochondrial respiratory chain enzymes. In many cases, the underlying molecular defect in the mtDNA can be identified. The efficacy of pharmacological therapies (e.g., coenzyme Q) has not been established so far. Symptomatic ophthalmological treatment includes ptosis and strabismus surgery. Early cardiac pacemaker implantation may be life-saving.
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Affiliation(s)
- Viktoria Bau
- Klinik und Poliklinik für Augenheilkunde, Martin-Luther-Universität Halle-Wittenberg, Ernst-Grube-Strasse 40, 06097 Halle/Saale, Germany.
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Atrophic gastritis: deficient complex I of the respiratory chain in the mitochondria of corpus mucosal cells. J Gastroenterol 2009; 43:780-8. [PMID: 18958547 DOI: 10.1007/s00535-008-2231-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Accepted: 05/29/2008] [Indexed: 02/06/2023]
Abstract
BACKGROUND Mitochondrial dysfunction is one of the most characteristic properties of the cancer cell. However, it is not known whether oxidative energy metabolism has already become altered in conditions of atrophic gastritis, a precancerous state of gastric disease. The purpose of our study was to comparatively characterize oxidative phosphorylation (OXPHOS) in the atrophic and nonatrophic gastric corpus mucosa. METHODS Mucosal biopsies were taken from 12 patients with corpus dominant atrophic gastritis and from 12 patients with nonatrophic mucosa (controls). One part of the tissue samples was permeabilized with saponin for analysis of the function of the respiratory chain using high-resolution respirometry, and another part was used for histopathological examination. The serum level of pepsinogen I (S-PGI) was determined with a specific enzyme immunoassay (EIA). RESULTS Compared to the control group, the maximal capacity of OXPHOS in the atrophy group was almost twofold lower, the respiratory chain complex I-dependent respiration, normalized to complex II-dependent respiration, was reduced, and respiratory control by ADP in the presence of succinate was increased in the atrophic corpus mucosa. In the whole cohort of the patients studied, serum S-PGI level correlated positively with complex I-dependent respiration or complex I-dependent to complex II-dependent respiration ratio. CONCLUSIONS Corpus dominant atrophic gastritis is characterized by decreased respiratory capacity and relative deficiency of the respiratory complex I of mitochondria in the mucosa, the latter defect probably limiting mitochondrial ATP production and energetic support of the secretory function of the zymogenic mucosal cells.
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Eimre M, Paju K, Pelloux S, Beraud N, Roosimaa M, Kadaja L, Gruno M, Peet N, Orlova E, Remmelkoor R, Piirsoo A, Saks V, Seppet E. Distinct organization of energy metabolism in HL-1 cardiac cell line and cardiomyocytes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2008; 1777:514-24. [PMID: 18423391 DOI: 10.1016/j.bbabio.2008.03.019] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2008] [Revised: 03/15/2008] [Accepted: 03/18/2008] [Indexed: 12/18/2022]
Abstract
Expression and function of creatine kinase (CK), adenylate kinase (AK) and hexokinase (HK) isoforms in relation to their roles in regulation of oxidative phosphorylation (OXPHOS) and intracellular energy transfer were assessed in beating (B) and non-beating (NB) cardiac HL-l cell lines and adult rat cardiomyocytes or myocardium. In both types of HL-1 cells, the AK2, CKB, HK1 and HK2 genes were expressed at higher levels than the CKM, CKMT2 and AK1 genes. Contrary to the saponin-permeabilized cardiomyocytes the OXPHOS was coupled to mitochondrial AK and HK but not to mitochondrial CK, and neither direct transfer of adenine nucleotides between CaMgATPases and mitochondria nor functional coupling between CK-MM and CaMgATPases was observed in permeabilized HL-1 cells. The HL-1 cells also exhibited deficient complex I of the respiratory chain. In conclusion, contrary to cardiomyocytes where mitochondria and CaMgATPases are organized into tight complexes which ensure effective energy transfer and feedback signaling between these structures via specialized pathways mediated by CK and AK isoforms and direct adenine nucleotide channeling, these complexes do not exist in HL-1 cells due to less organized energy metabolism.
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Affiliation(s)
- Margus Eimre
- Department of Pathophysiology, Centre of Molecular and Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
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Kosinski CM, Schlangen C, Gellerich FN, Gizatullina Z, Deschauer M, Schiefer J, Young AB, Landwehrmeyer GB, Toyka KV, Sellhaus B, Lindenberg KS. Myopathy as a first symptom of Huntington's disease in a Marathon runner. Mov Disord 2007; 22:1637-40. [PMID: 17534945 DOI: 10.1002/mds.21550] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
A semi professional marathon runner at risk for Huntington's disease (HD) (43 CAG repeats) developed signs of a slowly progressive myopathy with exercise-induced muscle fatigue, pain, elevated creatine kinase level, and worsening of his running performance many years before first signs of chorea were detected. Muscle biopsy displayed a mild myopathy with mitochondrial pathology including a complex IV deficiency and analysis of the patient's fibroblast culture demonstrated deficits in mitochondrial function. Challenging skeletal muscle by excessive training might have disclosed myopathy in HD even years before the appearance of other neurological symptoms.
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Böhm M, Papezova H, Hansikova H, Wenchich L, Zeman J. Activities of respiratory chain complexes in isolated platelets in females with anorexia nervosa. Int J Eat Disord 2007; 40:659-63. [PMID: 17584871 DOI: 10.1002/eat.20403] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE A broad spectrum of endocrine and biochemical disturbances was observed in patients with anorexia nervosa. In addition, metabolic changes may concern the efficiency of mitochondrial energy generating system. In our study we analyzed the activities of respiratory chain complexes in females with anorexia nervosa. METHOD The activities of respiratory chain complexes I, II, IV, I + III, and citrate synthase serving as the control enzyme were measured spectrophotometrically in isolated platelets in 36 females with anorexia nervosa (BMI 15 +/- 1.7) at the age 18-35 years and in 37 age related female controls (BMI 21 +/- 2.2). RESULTS In females with anorexia nervosa, the activities of respiratory chain complexes I and II in isolated platelets were significantly higher in comparison with controls. No differences were found in the activities of complexes IV and I + III and citrate synthase. CONCLUSION Our results suggest higher efficiency of some respiratory chain complexes in platelets in females with anorexia nervosa.
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Affiliation(s)
- Marek Böhm
- Centre of Applied Genomic, Department of Pediatrics, Faculty of Medicine, Charles University, Ke Karlovu 2, 128 08 Prague, Czech Republic
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Atamna H, Frey WH. Mechanisms of mitochondrial dysfunction and energy deficiency in Alzheimer's disease. Mitochondrion 2007; 7:297-310. [PMID: 17625988 DOI: 10.1016/j.mito.2007.06.001] [Citation(s) in RCA: 177] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Accepted: 06/06/2007] [Indexed: 12/31/2022]
Abstract
Several studies have demonstrated aberrations in the Electron Transport Complexes (ETC) and Krebs (TCA) cycle in Alzheimer's disease (AD) brain. Optimal activity of these key metabolic pathways depends on several redox active centers and metabolites including heme, coenzyme Q, iron-sulfur, vitamins, minerals, and micronutrients. Disturbed heme metabolism leads to increased aberrations in the ETC (loss of complex IV), dimerization of APP, free radical production, markers of oxidative damage, and ultimately cell death all of which represent key cytopathologies in AD. The mechanism of mitochondrial dysfunction in AD is controversial. The observations that Abeta is found both in the cells and in the mitochondria and that Abeta binds with heme may provide clues to this mechanism. Mitochondrial Abeta may interfere with key metabolites or metabolic pathways in a manner that overwhelms the mitochondrial mechanisms of repair. Identifying the molecular mechanism for how Abeta interferes with mitochondria and that explains the established key cytopathologies in AD may also suggest molecular targets for therapeutic interventions. Below we review recent studies describing the possible role of Abeta in altered energy production through heme metabolism. We further discuss how protecting mitochondria could confer resistance to oxidative and environmental insults. Therapies targeted at protecting mitochondria may improve the clinical outcome of AD patients.
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Affiliation(s)
- Hani Atamna
- Nutrition and Metabolism Center, Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA 94609-1673, USA.
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Sarzi E, Bourdon A, Chrétien D, Zarhrate M, Corcos J, Slama A, Cormier-Daire V, de Lonlay P, Munnich A, Rötig A. Mitochondrial DNA depletion is a prevalent cause of multiple respiratory chain deficiency in childhood. J Pediatr 2007; 150:531-4, 534.e1-6. [PMID: 17452231 DOI: 10.1016/j.jpeds.2007.01.044] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2006] [Revised: 09/16/2006] [Accepted: 01/27/2007] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To determine the actual incidence of mitochondrial DNA (mtDNA) depletion syndrome in multiple respiratory chain deficiency. STUDY DESIGN We carried out a real-time polymerase chain reaction quantification of mtDNA in liver or muscle tissue of 100 children with unexplained multiple oxidative phosphorylation enzyme deficiency. RESULTS A reduction of mtDNA copy number to <35% of control values was found in liver and/or muscle in half of the children (50/100). Most of these patients (32/50; 64%) presented with severe neonatal onset liver involvement; 7 (14%) had Alpers syndrome, and 11 (22%) exhibited various forms of neurologic involvement. Deoxyguanosine kinase or polymerase gamma (POLG) mutations could be identified in 11 of 32 patients with liver involvement, and POLG mutations were consistently found in all 7 patients with Alpers syndrome. Homozygous thymidine kinase 2 and MPV17 gene mutations were found in 2 patients. CONCLUSIONS Our findings show that mtDNA depletion is a prevalent cause of multiple respiratory chain deficiency in infancy.
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Kuhnt T, Pelz T, Qu X, Hänsgen G, Dunst J, Gellerich FN. Mitochondrial OXPHOS functions in R1H rhabdomyosarcoma and skeletal muscles of the rat. Neurochem Res 2007; 32:973-80. [PMID: 17273927 DOI: 10.1007/s11064-006-9254-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2006] [Accepted: 12/12/2006] [Indexed: 10/23/2022]
Abstract
The aim of the study was to determinate mitochondrial oxidative phosphorylation (OXPHOS) functions in rat rhabdomyosarcoma R1H (R1H) and rat skeletal muscles. For that purpose skinned fiber technique and multiple substrate inhibitor titration were adapted to tumor samples. In our animal tumor model (R1H) functional abnormalities of OXPHOS were found compared to skeletal muscles. In R1H the state 3 respiration of pyruvate + malate was decreased: 0.56 +/- 0.28 nmol O(2)/mg/min versus 2.32 +/- 1.19 nmol O(2)/mg/min, P < 0.001, whereas the state 3 respiration of succinate + rotenone was increased: 36 +/- 14% versus 19 +/- 11%, P < 0.001. In R1H the rotenone-insensitive respiration reached higher levels than the antimycin A-insensitive respiration, whereas in normal muscles the converse was observed. Additionally, the obvious difference between the CAT- and the antimycin A-independent respiration indicates an increased part of leak respiration in R1H. By now, the high feasibility of these techniques is appreciated for the investigation of muscles and prospectively for tumors, too.
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Affiliation(s)
- Thomas Kuhnt
- Department of Radiotherapy, Martin-Luther-University, Halle-Wittenberg, Halle, Saale, Germany.
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Alemi M, Prigione A, Wong A, Schoenfeld R, DiMauro S, Hirano M, Taroni F, Cortopassi G. Mitochondrial DNA deletions inhibit proteasomal activity and stimulate an autophagic transcript. Free Radic Biol Med 2007; 42:32-43. [PMID: 17157191 PMCID: PMC1927835 DOI: 10.1016/j.freeradbiomed.2006.09.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 07/29/2006] [Accepted: 09/14/2006] [Indexed: 01/01/2023]
Abstract
Deletions within the mitochondrial DNA (mtDNA) cause Kearns Sayre syndrome (KSS) and chronic progressive external opthalmoplegia (CPEO). The clinical signs of KSS include muscle weakness, heart block, pigmentary retinopathy, ataxia, deafness, short stature, and dementia. The identical deletions occur and rise exponentially as humans age, particularly in substantia nigra. Deletions at >30% concentration cause deficits in basic bioenergetic parameters, including membrane potential and ATP synthesis, but it is poorly understood how these alterations cause the pathologies observed in patients. To better understand the consequences of mtDNA deletions, we microarrayed six cell types containing mtDNA deletions from KSS and CPEO patients. There was a prominent inhibition of transcripts encoding ubiquitin-mediated proteasome activity, and a prominent induction of transcripts involved in the AMP kinase pathway, macroautophagy, and amino acid degradation. In mutant cells, we confirmed a decrease in proteasome biochemical activity, significantly lower concentration of several amino acids, and induction of an autophagic transcript. An interpretation consistent with the data is that mtDNA deletions increase protein damage, inhibit the ubiquitin-proteasome system, decrease amino acid salvage, and activate autophagy. This provides a novel pathophysiological mechanism for these diseases, and suggests potential therapeutic strategies.
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Affiliation(s)
- Mansour Alemi
- Department of Molecular Biosciences, 1311 Haring Hall, University of California, Davis, CA 95616, USA
| | - Alessandro Prigione
- Department of Molecular Biosciences, 1311 Haring Hall, University of California, Davis, CA 95616, USA
| | - Alice Wong
- Department of Molecular Biosciences, 1311 Haring Hall, University of California, Davis, CA 95616, USA
| | - Robert Schoenfeld
- Department of Molecular Biosciences, 1311 Haring Hall, University of California, Davis, CA 95616, USA
| | - Salvatore DiMauro
- Department of Neurology, Columbia University Medical Center, 630 West 168 Street, New York, NY 10032
| | - Michio Hirano
- Department of Neurology, Columbia University Medical Center, 630 West 168 Street, New York, NY 10032
| | - Franco Taroni
- Division of Biochemistry and Genetics, Istituto Nazionale Neurologico Carlo Besta, Milan, Italy
| | - Gino Cortopassi
- Department of Molecular Biosciences, 1311 Haring Hall, University of California, Davis, CA 95616, USA
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Deschauer M, Gizatullina Z, Schulze A, Pritsch M, Knöppel C, Knape M, Zierz S, Gellerich FN. Molecular and biochemical investigations in fumarase deficiency. Mol Genet Metab 2006; 88:146-52. [PMID: 16510303 DOI: 10.1016/j.ymgme.2006.01.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Revised: 01/13/2006] [Accepted: 01/18/2006] [Indexed: 11/19/2022]
Abstract
Fumarase (FH) deficiency is a rare autosomal recessive disease of the Krebs cycle causing severe neurological impairment in early childhood, characterized by encephalopathy with seizures and muscular hypotonia. Only a handful of patients with various recessive mutations in the FH gene have been described so far. Interestingly, autosomal dominant mutations in the same gene are associated with hereditary leiomyomatosis and renal cell cancer (HLRCC). We investigated a boy with developmental and growth delay, microcephaly, and muscular hypotonia recognized at the age of 3 months. No leiomyomatosis or renal cancer is known in the parents. Investigation of the patient's urine revealed massive fumarate excretion. FH activity was severely reduced in muscle and fibroblasts. Respirometric investigation of fibroblasts showed only modest changes indicating that fumarate mediated inhibition of enzymatic pathways other than oxidative phosphorylation might be more relevant in pathophysiology of FH deficiency. Molecular analysis revealed a known 435insK mutation on the paternal allele and a novel H275L mutation due to an A to T transversion of nucleotide 824 on the maternal allele. This mutation affects the same codon as a C to T transition of nucleotide 823, resulting in a H275Y mutation that was found in two families with HLRCC.
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Affiliation(s)
- M Deschauer
- Neurologische Klinik der Universität Halle-Wittenberg, Germany.
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Gruno M, Peet N, Seppet E, Kadaja L, Paju K, Eimre M, Orlova E, Peetsalu M, Tein A, Soplepmann J, Schlattner U, Peetsalu A, Seppet EK. Oxidative phosphorylation and its coupling to mitochondrial creatine and adenylate kinases in human gastric mucosa. Am J Physiol Regul Integr Comp Physiol 2006; 291:R936-46. [PMID: 16741143 DOI: 10.1152/ajpregu.00162.2006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Energy metabolism in gastrobiopsy specimens of the antral and corpus mucosa, treated with saponin to permeabilize the cells, was studied in patients with gastric diseases. The results show twice lower oxidative capacity in the antral mucosa than in the corpus mucosa and the relative deficiency of antral mitochondria in complex I. The mucosal cells expressed mitochondrial and cytosolic isoforms of creatine kinase and adenylate kinase (AK). Creatine (20 mM) and AMP (2 mM) markedly stimulated mitochondrial respiration in the presence of submaximal ADP or ATP concentrations, and creatine reduced apparent Km for ADP in stimulation of respiration, which indicates the functional coupling of mitochondrial kinases to oxidative phosphorylation. Addition of exogenous cytochrome c increased ADP-dependent respiration, and the large-scale cytochrome c effect (>or=20%) was associated with suppressed stimulation of respiration by creatine and AMP in the mucosal preparations. These results point to the impaired mitochondrial outer membrane, probably attributed to the pathogenic effects of Helicobacter pylori. Compared with the corpus mucosa, the antral mucosa exhibited greater sensitivity to such type of injury as the prevalence of the large-scale cytochrome c effect was twice higher among the latter specimens. Active chronic gastritis was associated with decreased respiratory capacity of the corpus mucosa but with its increase in the antral mucosa. In conclusion, human gastric mucosal cells express the mitochondrial and cytosolic isoforms of CK and AK participating in intracellular energy transfer systems. Gastric mucosa disease is associated with the altered functions of these systems and oxidative phosphorylation.
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Affiliation(s)
- Marju Gruno
- Department of Pathophysiology, Faculty of Medicine, Univ. of Tartu, 19 Ravila St., 50411 Tartu, Estonia
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