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Scaini G, Andrews T, Lima CNC, Benevenuto D, Streck EL, Quevedo J. Mitochondrial dysfunction as a critical event in the pathophysiology of bipolar disorder. Mitochondrion 2021; 57:23-36. [PMID: 33340709 PMCID: PMC10494232 DOI: 10.1016/j.mito.2020.12.002] [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] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/18/2020] [Accepted: 12/10/2020] [Indexed: 01/02/2023]
Abstract
The understanding of the pathophysiology of bipolar disorder (BD) remains modest, despite recent advances in neurobiological research. The mitochondrial dysfunction hypothesis of bipolar disorder has been corroborated by several studies involving postmortem brain analysis, neuroimaging, and specific biomarkers in both rodent models and humans. Evidence suggests that BD might be related to abnormal mitochondrial morphology and dynamics, neuroimmune dysfunction, and atypical mitochondrial metabolism and oxidative stress pathways. Mitochondrial dysfunction in mood disorders is also associated with abnormal Ca2+ levels, glutamate excitotoxicity, an imbalance between pro- and antiapoptotic proteins towards apoptosis, abnormal gene expression of electron transport chain complexes, and decreased ATP synthesis. This paper aims to review and discuss the implications of mitochondrial dysfunction in BD etiology and to explore mitochondria as a potential target for novel therapeutic agents.
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Affiliation(s)
- Giselli Scaini
- Translational Psychiatry Program, Louis A. Faillace, MD, Department of Psychiatry and Behavioral Sciences at McGovern Medical School, The University of Texas Health Science Center at Houston (UT Health), Houston, TX, USA
| | - Taylor Andrews
- Translational Psychiatry Program, Louis A. Faillace, MD, Department of Psychiatry and Behavioral Sciences at McGovern Medical School, The University of Texas Health Science Center at Houston (UT Health), Houston, TX, USA
| | - Camila N C Lima
- Translational Psychiatry Program, Louis A. Faillace, MD, Department of Psychiatry and Behavioral Sciences at McGovern Medical School, The University of Texas Health Science Center at Houston (UT Health), Houston, TX, USA
| | - Deborah Benevenuto
- Translational Psychiatry Program, Louis A. Faillace, MD, Department of Psychiatry and Behavioral Sciences at McGovern Medical School, The University of Texas Health Science Center at Houston (UT Health), Houston, TX, USA
| | - Emilio L Streck
- Laboratory of Experimental Neurology, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil
| | - João Quevedo
- Translational Psychiatry Program, Louis A. Faillace, MD, Department of Psychiatry and Behavioral Sciences at McGovern Medical School, The University of Texas Health Science Center at Houston (UT Health), Houston, TX, USA; Translational Psychiatry Laboratory, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil; Center of Excellence on Mood Disorders, Louis A. Faillace, MD, Department of Psychiatry and Behavioral Sciences at McGovern Medical School, The University of Texas Health Science Center at Houston (UT Health), Houston, TX, USA; Neuroscience Graduate Program, The University of Texas MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, Houston, TX, USA.
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Esterhuizen K, Lindeque JZ, Mason S, van der Westhuizen FH, Rodenburg RJ, de Laat P, Smeitink JAM, Janssen MCH, Louw R. One mutation, three phenotypes: novel metabolic insights on MELAS, MIDD and myopathy caused by the m.3243A > G mutation. Metabolomics 2021; 17:10. [PMID: 33438095 DOI: 10.1007/s11306-020-01769-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 12/31/2020] [Indexed: 12/19/2022]
Abstract
INTRODUCTION The m.3243A > G mitochondrial DNA mutation is one of the most common mitochondrial disease-causing mutations, with a carrier rate as high as 1:400. This point mutation affects the MT-TL1 gene, ultimately affecting the oxidative phosphorylation system and the cell's energy production. Strikingly, the m.3243A > G mutation is associated with different phenotypes, including mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS), maternally inherited diabetes and deafness (MIDD) and myopathy. OBJECTIVES We investigated urine metabolomes of MELAS, MIDD and myopathy patients in order to identify affected metabolic pathways and possible treatment options. METHODS A multiplatform metabolomics approach was used to comprehensively analyze the metabolome and compare metabolic profiles of different phenotypes caused by the m.3243A > G mutation. Our analytical array consisted of NMR spectroscopy, LC-MS/MS and GC-TOF-MS. RESULTS The investigation revealed phenotypic specific metabolic perturbations, as well as metabolic similarities between the different phenotypes. We show that glucose metabolism is highly disturbed in the MIDD phenotype, but not in MELAS or myopathy, remodeled fatty acid oxidation is characteristic of the MELAS patients, while one-carbon metabolism is strongly modified in both MELAS and MIDD, but not in the myopathy group. Lastly we identified increased creatine in the urine of the myopathy patients, but not in MELAS or MIDD. CONCLUSION We conclude by giving novel insight on the phenotypes of the m.3243A > G mutation from a metabolomics point of view. Directives are also given for future investigations that could lead to better treatment options for patients suffering from this debilitating disease.
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Affiliation(s)
- Karien Esterhuizen
- Mitochondria Research Laboratory, Human Metabolomics, North-West University, Potchefstroom, South Africa
| | - J Zander Lindeque
- Mitochondria Research Laboratory, Human Metabolomics, North-West University, Potchefstroom, South Africa
| | - Shayne Mason
- Mitochondria Research Laboratory, Human Metabolomics, North-West University, Potchefstroom, South Africa
| | | | - Richard J Rodenburg
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Paul de Laat
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Jan A M Smeitink
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Mirian C H Janssen
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
- Department of Internal Medicine, Radboud Center for Mitochondrial Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Roan Louw
- Mitochondria Research Laboratory, Human Metabolomics, North-West University, Potchefstroom, South Africa.
- Human Metabolomics, Faculty of Natural and Agricultural Sciences, North-West University, Potchefstroom Campus, Private Bag X6001, Potchefstroom, South Africa.
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Esterhuizen K, Lindeque JZ, Mason S, van der Westhuizen FH, Suomalainen A, Hakonen AH, Carroll CJ, Rodenburg RJ, de Laat PB, Janssen MC, Smeitink JA, Louw R. A urinary biosignature for mitochondrial myopathy, encephalopathy, lactic acidosis and stroke like episodes (MELAS). Mitochondrion 2019; 45:38-45. [DOI: 10.1016/j.mito.2018.02.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 01/27/2018] [Accepted: 02/15/2018] [Indexed: 12/27/2022]
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Venter M, van der Westhuizen FH, Elson JL. The aetiology of cardiovascular disease: a role for mitochondrial DNA? Cardiovasc J Afr 2017; 29:122-132. [PMID: 28906532 PMCID: PMC6009096 DOI: 10.5830/cvja-2017-037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 07/17/2017] [Indexed: 01/03/2023] Open
Abstract
Cardiovascular disease (CVD) is a world-wide cause of mortality in humans and its incidence is on the rise in Africa. In this review, we discuss the putative role of mitochondrial dysfunction in the aetiology of CVD and consequently identify mitochondrial DNA (mtDNA) variation as a viable genetic risk factor to be considered. We then describe the contribution and pitfalls of several current approaches used when investigating mtDNA in relation to complex disease. We also propose an alternative approach, the adjusted mutational load hypothesis, which would have greater statistical power with cohorts of moderate size, and is less likely to be affected by population stratification. We therefore address some of the shortcomings of the current haplogroup association approach. Finally, we discuss the unique challenges faced by studies done on African populations, and recommend the most viable methods to use when investigating mtDNA variation in CVD and other common complex disease.
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Affiliation(s)
- Marianne Venter
- Human Metabolomics, North-West University, Potchefstroom, South Africa.
| | | | - Joanna L Elson
- Human Metabolomics, North-West University, Potchefstroom, South Africa; Institute of Genetic Medicine, Newcastle University, United Kingdom
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Metabolomics of mitochondrial disease. Mitochondrion 2017; 35:97-110. [DOI: 10.1016/j.mito.2017.05.012] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 05/08/2017] [Accepted: 05/26/2017] [Indexed: 12/21/2022]
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Lukyanova LD, Kirova YI. Mitochondria-controlled signaling mechanisms of brain protection in hypoxia. Front Neurosci 2015; 9:320. [PMID: 26483619 PMCID: PMC4589588 DOI: 10.3389/fnins.2015.00320] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 08/27/2015] [Indexed: 01/06/2023] Open
Abstract
The article is focused on the role of the cell bioenergetic apparatus, mitochondria, involved in development of immediate and delayed molecular mechanisms for adaptation to hypoxic stress in brain cortex. Hypoxia induces reprogramming of respiratory chain function and switching from oxidation of NAD-related substrates (complex I) to succinate oxidation (complex II). Transient, reversible, compensatory activation of respiratory chain complex II is a major mechanism of immediate adaptation to hypoxia necessary for (1) succinate-related energy synthesis in the conditions of oxygen deficiency and formation of urgent resistance in the body; (2) succinate-related stabilization of HIF-1α and initiation of its transcriptional activity related with formation of long-term adaptation; (3) succinate-related activation of the succinate-specific receptor, GPR91. This mechanism participates in at least four critical regulatory functions: (1) sensor function related with changes in kinetic properties of complex I and complex II in response to a gradual decrease in ambient oxygen concentration; this function is designed for selection of the most efficient pathway for energy substrate oxidation in hypoxia; (2) compensatory function focused on formation of immediate adaptive responses to hypoxia and hypoxic resistance of the body; (3) transcriptional function focused on activated synthesis of HIF-1 and the genes providing long-term adaptation to low pO2; (4) receptor function, which reflects participation of mitochondria in the intercellular signaling system via the succinate-dependent receptor, GPR91. In all cases, the desired result is achieved by activation of the succinate-dependent oxidation pathway, which allows considering succinate as a signaling molecule. Patterns of mitochondria-controlled activation of GPR-91- and HIF-1-dependent reaction were considered, and a possibility of their participation in cellular-intercellular-systemic interactions in hypoxia and adaptation was proved.
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Affiliation(s)
- Ludmila D. Lukyanova
- Laboratory for Bioenergetics and Hypoxia, Institute of General Pathology and PathophysiologyMoscow, Russia
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7
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Jochmanová I, Zhuang Z, Pacak K. Pheochromocytoma: Gasping for Air. Discov Oncol 2015; 6:191-205. [PMID: 26138106 DOI: 10.1007/s12672-015-0231-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 06/19/2015] [Indexed: 02/06/2023] Open
Abstract
There has been increasing evidence that pseudohypoxia--a phenomenon that we refer to as "gasping for air"--along with mitochondrial enzyme dysregulation play a crucial role in tumorigenesis, particularly in several hereditary pheochromocytomas (PHEOs) and paragangliomas (PGLs). Alterations in key tricarboxylic acids (TCA) cycle enzymes (SDH, FH, MDH2) have been shown to induce pseudohypoxia via activation of the hypoxia-inducible transcription factor (HIF) signaling pathway that is involved in tumorigenesis, invasiveness, and metastatic spread, including an association with resistance to various cancer therapies and worse prognosis. This review outlines the ongoing story of the pathogenesis of hereditary PHEOs/PGLs, showing the unique and most updated evidence of TCA cycle dysregulation that is tightly linked to hypoxia signaling.
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Affiliation(s)
- Ivana Jochmanová
- Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver NICHD, National Institutes of Health, Building 10, CRC, 1-East, Room 1E-3140, 10 Center Drive, MSC-1109, Bethesda, MD, 20892-1109, USA.,1st Department of Internal Medicine, Medical Faculty, P. J. Šafárik University in Košice, Trieda SNP 1, 04011, Košice, Slovakia
| | - Zhengping Zhuang
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Karel Pacak
- Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver NICHD, National Institutes of Health, Building 10, CRC, 1-East, Room 1E-3140, 10 Center Drive, MSC-1109, Bethesda, MD, 20892-1109, USA.
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8
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Turnbull DM, Rustin P. Genetic and biochemical intricacy shapes mitochondrial cytopathies. Neurobiol Dis 2015; 92:55-63. [PMID: 25684538 DOI: 10.1016/j.nbd.2015.02.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 01/22/2015] [Accepted: 02/03/2015] [Indexed: 12/17/2022] Open
Abstract
The major progress made in the identification of the molecular bases of mitochondrial disease has revealed the huge diversity of their origin. Today up to 300 mutations were identified in the mitochondrial genome and about 200 nuclear genes are possibly mutated. In this review, we highlight a number of features specific to mitochondria which possibly participate in the complexity of these diseases. These features include both the complexity of mitochondrial genetics and the multiplicity of the roles ensured by the organelles in numerous aspects of cell life and death. This spectacular complexity presumably accounts for the present lack of an efficient therapy in the vast majority of cases.
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Affiliation(s)
- Douglass M Turnbull
- Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Newcastle University, Framlington Road, Newcastle upon Tyne NE2 4HH, UK
| | - Pierre Rustin
- INSERM UMR 1141, Hôpital Robert Debré, Paris, France; Université Paris 7, Faculté de Médecine Denis Diderot, Paris, France.
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El-Khoury R, Kemppainen KK, Dufour E, Szibor M, Jacobs HT, Rustin P. Engineering the alternative oxidase gene to better understand and counteract mitochondrial defects: state of the art and perspectives. Br J Pharmacol 2014; 171:2243-9. [PMID: 24383965 DOI: 10.1111/bph.12570] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 10/25/2013] [Accepted: 11/18/2013] [Indexed: 12/22/2022] Open
Abstract
Mitochondrial disorders are nowadays recognized as impinging on most areas of medicine. They include specific and widespread organ involvement, including both tissue degeneration and tumour formation. Despite the spectacular progresses made in the identification of their underlying molecular basis, effective therapy remains a distant goal. Our still rudimentary understanding of the pathophysiological mechanisms by which these diseases arise constitutes an obstacle to developing any rational treatments. In this context, the idea of using a heterologous gene, encoding a supplemental oxidase otherwise absent from mammals, potentially bypassing the defective portion of the respiratory chain, was proposed more than 10 years ago. The recent progress made in the expression of the alternative oxidase in a wide range of biological systems and disease conditions reveals great potential benefit, considering the broad impact of mitochondrial diseases. This review addresses the state of the art and the perspectives that can be now envisaged by using this strategy.
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Affiliation(s)
- Riyad El-Khoury
- INSERM UMR 1141, Paris, France; Université Paris 7, Paris, France
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10
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Streck EL, Gonçalves CL, Furlanetto CB, Scaini G, Dal-Pizzol F, Quevedo J. Mitochondria and the central nervous system: searching for a pathophysiological basis of psychiatric disorders. REVISTA BRASILEIRA DE PSIQUIATRIA 2014; 36:156-67. [DOI: 10.1590/1516-4446-2013-1224] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 10/03/2013] [Indexed: 12/20/2022]
Affiliation(s)
- Emilio L. Streck
- Universidade do Extremo Sul Catarinense (UNESC), Brazil; National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil
| | - Cinara L. Gonçalves
- Universidade do Extremo Sul Catarinense (UNESC), Brazil; National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil
| | - Camila B. Furlanetto
- Universidade do Extremo Sul Catarinense (UNESC), Brazil; National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil
| | - Giselli Scaini
- Universidade do Extremo Sul Catarinense (UNESC), Brazil; National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil
| | - Felipe Dal-Pizzol
- Universidade do Extremo Sul Catarinense (UNESC), Brazil; National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil
| | - João Quevedo
- National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil; UNESC, Brazil
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11
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Jochmanová I, Yang C, Zhuang Z, Pacak K. Hypoxia-inducible factor signaling in pheochromocytoma: turning the rudder in the right direction. J Natl Cancer Inst 2013; 105:1270-83. [PMID: 23940289 DOI: 10.1093/jnci/djt201] [Citation(s) in RCA: 124] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Many solid tumors, including pheochromocytoma (PHEO) and paraganglioma (PGL), are characterized by a (pseudo)hypoxic signature. (Pseudo)hypoxia has been shown to promote both tumor progression and resistance to therapy. The major mediators of the transcriptional hypoxic response are hypoxia-inducible factors (HIFs). High levels of HIFs lead to transcription of hypoxia-responsive genes, which are involved in tumorigenesis. PHEOs and PGLs are catecholamine-producing tumors arising from sympathetic- or parasympathetic-derived chromaffin tissue. In recent years, substantial progress has been made in understanding the metabolic disturbances present in PHEO and PGL, especially because of the identification of some disease-susceptibility genes. To date, fifteen PHEO and PGL susceptibility genes have been identified. Based on the main transcription signatures of the mutated genes, PHEOs and PGLs have been divided into two clusters, pseudohypoxic cluster 1 and cluster 2, rich in kinase receptor signaling and protein translation pathways. Although these two clusters seem to show distinct signaling pathways, recent data suggest that both clusters are interconnected by HIF signaling as the important driver in their tumorigenesis, and mutations in most PHEO and PGL susceptibility genes seem to affect HIF-α regulation and its downstream signaling pathways. HIF signaling appears to play an important role in the development and growth of PHEOs and PGLs, which could suggest new therapeutic approaches for the treatment of these tumors.
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Affiliation(s)
- Ivana Jochmanová
- Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-1109, USA
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Li CC, Wu TS, Huang CF, Jang LT, Liu YT, You ST, Liou GG, Lee FJS. GTP-binding-defective ARL4D alters mitochondrial morphology and membrane potential. PLoS One 2012; 7:e43552. [PMID: 22927989 PMCID: PMC3424131 DOI: 10.1371/journal.pone.0043552] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Accepted: 07/23/2012] [Indexed: 12/01/2022] Open
Abstract
ARL4D, ARL4A, and ARL4C are closely related members of the ADP-ribosylation factor/ARF-like protein (ARF/ARL) family of GTPases. All three ARL4 proteins contain nuclear localization signals (NLSs) at their C-termini and are primarily found at the plasma membrane, but they are also present in the nucleus and cytoplasm. ARF function and localization depends on their controlled binding and hydrolysis of GTP. Here we show that GTP-binding-defective ARL4D is targeted to the mitochondria, where it affects mitochondrial morphology and function. We found that a portion of endogenous ARL4D and the GTP-binding-defective ARL4D mutant ARL4D(T35N) reside in the mitochondria. The N-terminal myristoylation of ARL4D(T35N) was required for its localization to mitochondria. The localization of ARL4D(T35N) to the mitochondria reduced the mitochondrial membrane potential (ΔΨm) and caused mitochondrial fragmentation. Furthermore, the C-terminal NLS region of ARL4D(T35N) was required for its effect on the mitochondria. This study is the first to demonstrate that the dysfunctional GTP-binding-defective ARL4D is targeted to mitochondria, where it subsequently alters mitochondrial morphology and membrane potential.
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Affiliation(s)
- Chun-Chun Li
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Tsung-Sheng Wu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chun-Fang Huang
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Li-Ting Jang
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
- Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan
| | - Yu-Tsan Liu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shu-Ting You
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Gunn-Guang Liou
- Division of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli, Taiwan
| | - Fang-Jen S. Lee
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
- Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan
- * E-mail:
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HIV-1 Tat protein directly induces mitochondrial membrane permeabilization and inactivates cytochrome c oxidase. Cell Death Dis 2012; 3:e282. [PMID: 22419111 PMCID: PMC3317353 DOI: 10.1038/cddis.2012.21] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The Trans-activator protein (Tat) of human immunodeficiency virus (HIV)
is a pleiotropic protein involved in different aspects of AIDS pathogenesis. As
a number of viral proteins Tat is suspected to disturb mitochondrial function.
We prepared pure synthetic full-length Tat by native chemical ligation (NCL),
and Tat peptides, to evaluate their direct effects on isolated mitochondria.
Submicromolar doses of synthetic Tat cause a rapid dissipation of the
mitochondrial transmembrane potential (ΔΨm) as well as
cytochrome c release in mitochondria isolated from mouse liver, heart,
and brain. Accordingly, Tat decreases substrate oxidation by mitochondria
isolated from these tissues, with oxygen uptake being initially restored by
adding cytochrome c. The anion-channel inhibitor
4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS) protects
isolated mitochondria against Tat-induced mitochondrial membrane
permeabilization (MMP), whereas ruthenium red, a ryanodine receptor blocker,
does not. Pharmacologic inhibitors of the permeability transition pore,
Bax/Bak inhibitors, and recombinant Bcl-2 and Bcl-XL proteins do not reduce
Tat-induced MMP. We finally observed that Tat inhibits cytochrome c
oxidase (COX) activity in disrupted mitochondria isolated from liver, heart, and
brain of both mouse and human samples, making it the first described viral
protein to be a potential COX inhibitor.
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Golubitzky A, Dan P, Weissman S, Link G, Wikstrom JD, Saada A. Screening for active small molecules in mitochondrial complex I deficient patient's fibroblasts, reveals AICAR as the most beneficial compound. PLoS One 2011; 6:e26883. [PMID: 22046392 PMCID: PMC3202581 DOI: 10.1371/journal.pone.0026883] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Accepted: 10/05/2011] [Indexed: 01/13/2023] Open
Abstract
Congenital deficiency of the mitochondrial respiratory chain complex I (CI) is a common defect of oxidative phosphorylation (OXPHOS). Despite major advances in the biochemical and molecular diagnostics and the deciphering of CI structure, function assembly and pathomechanism, there is currently no satisfactory cure for patients with mitochondrial complex I defects. Small molecules provide one feasible therapeutic option, however their use has not been systematically evaluated using a standardized experimental system. In order to evaluate potentially therapeutic compounds, we set up a relatively simple system measuring different parameters using only a small amount of patient's fibroblasts, in glucose free medium, where growth is highly OXPOS dependent. Ten different compounds were screened using fibroblasts derived from seven CI patients, harboring different mutations. 5-Aminoimidazole-4-carboxamide ribotide (AICAR) was found to be the most beneficial compound improving growth and ATP content while decreasing ROS production. AICAR also increased mitochondrial biogenesis without altering mitochondrial membrane potential (Δψ). Fluorescence microscopy data supported increased mitochondrial biogenesis and activation of the AMP activated protein kinase (AMPK). Other compounds such as; bezafibrate and oltipraz were rated as favorable while polyphenolic phytochemicals (resverastrol, grape seed extract, genistein and epigallocatechin gallate) were found not significant or detrimental. Although the results have to be verified by more thorough investigation of additional OXPHOS parameters, preliminary rapid screening of potential therapeutic compounds in individual patient's fibroblasts could direct and advance personalized medical treatment.
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Affiliation(s)
- Anna Golubitzky
- Monique and Jacques Roboh Department of Genetic Research, Department of Genetics and Metabolic Diseases, Hadassah, Hebrew University Medical Center, Jerusalem, Israel.
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Anflous-Pharayra K, Lee N, Armstrong DL, Craigen WJ. VDAC3 has differing mitochondrial functions in two types of striated muscles. BIOCHIMICA ET BIOPHYSICA ACTA 2011; 1807:150-6. [PMID: 20875390 PMCID: PMC2998388 DOI: 10.1016/j.bbabio.2010.09.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Revised: 09/16/2010] [Accepted: 09/20/2010] [Indexed: 10/19/2022]
Abstract
Voltage-dependent anion channel (VDAC) is an abundant mitochondrial outer membrane protein. In mammals, three VDAC isoforms have been characterized. We have previously reported alterations in the function of mitochondria when assessed in situ in different muscle types in VDAC1 deficient mice (Anflous et al., 2001). In the present report we extend the study to VDAC3 deficient muscles and measure the respiratory enzyme activity in both VDAC1 and VDAC3 deficient muscles. While in the heart the absence of VDAC3 causes a decrease in the apparent affinity of in situ mitochondria for ADP, in the gastrocnemius, a mixed glycolytic/oxidative muscle, the affinity of in situ mitochondria for ADP remains unchanged. The absence of VDAC1 causes multiple defects in respiratory complex activities in both types of muscle. However, in VDAC3 deficient mice the defect is restricted to the heart and only to complex IV. These functional alterations correlate with structural aberrations of mitochondria. These results demonstrate that, unlike VDAC1, there is muscle-type specificity for VDAC3 function and therefore in vivo these two isoforms may fulfill different physiologic functions.
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Affiliation(s)
- Keltoum Anflous-Pharayra
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
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Goncalves S, Paupe V, Dassa EP, Brière JJ, Favier J, Gimenez-Roqueplo AP, Bénit P, Rustin P. Rapid determination of tricarboxylic acid cycle enzyme activities in biological samples. BMC BIOCHEMISTRY 2010; 11:5. [PMID: 20109171 PMCID: PMC2823639 DOI: 10.1186/1471-2091-11-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Accepted: 01/28/2010] [Indexed: 11/10/2022]
Abstract
Background In the last ten years, deficiencies in tricarboxylic acid cycle (TCAC) enzymes have been shown to cause a wide spectrum of human diseases, including malignancies and neurological and cardiac diseases. A prerequisite to the identification of disease-causing TCAC enzyme deficiencies is the availability of effective enzyme assays. Results We developed three assays that measure the full set of TCAC enzymes. One assay relies on the sequential addition of reagents to measure succinyl-CoA ligase activity, followed by succinate dehydrogenase, fumarase and, finally, malate dehydrogenase. Another assay measures the activity of α-ketoglutarate dehydrogenase followed by aconitase and isocitrate dehydrogenase. The remaining assay measures citrate synthase activity using a standard procedure. We used these assays successfully on extracts of small numbers of human cells displaying various severe or partial TCAC deficiencies and on frozen heart homogenates from heterozygous mice harboring an SDHB gene deletion. Conclusion This set of assays is rapid and simple to use and can immediately detect even partial defects, as the activity of each enzyme can be readily compared with one or more other activities measured in the same sample.
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Rustin P, Jacobs HT. Respiratory chain alternative enzymes as tools to better understand and counteract respiratory chain deficiencies in human cells and animals. PHYSIOLOGIA PLANTARUM 2009; 137:362-370. [PMID: 19508504 DOI: 10.1111/j.1399-3054.2009.01249.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Mitochondrial respiratory chain defects are now recognized to underlie a large number of human diseases with a spectacular variety in their phenotypic presentations. Despite progress made in the elucidation of their molecular basis, these diseases remain essentially untreatable. To date, most strategies to counteract these diseases, either in vitro or in vivo have proven unsuccessful. In humans, the respiratory chain lacks several redox active proteins long known in many micro-organisms, as well as in plants, and, as found recently, even in some metazoans. These alternative enzymes, e.g. the cyanide-insensitive alternative oxidase and the internal rotenone-insensitive NADH dehydrogenase, confer a significant flexibility to the respiratory chain, allowing it to overcome potential constraints exerted by the cell phosphorylation potential or by environmental xenobiotics. In plants, these alternative enzymes, activated by a subset of keto-acids, including pyruvate, are essentially engaged under highly reducing conditions. Because these are conditions observed in patients with respiratory chain dysfunction, we made the hypothesis that expression of these proteins might be of benefit in such situations. The observation that a functional alternative oxidase from Ciona intestinalis could be expressed in mammalian cells without obvious detrimental effect has provided a basis to develop a research programme to test the hypothesis, within an ad hoc international consortium, that this paper aims to describe. Combining research on human cells, flies and mice, the project aims, firstly, to verify that expressing these alternative enzymes is physiologically benign, useful as a tool to delineate the mechanisms of respiratory chain dysfunction and, finally, test their potential therapeutic benefit.
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Affiliation(s)
- Pierre Rustin
- INSERM U676 and Université Paris 7, Faculté de Médecine Denis Diderot, Paris, France.
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Respiratory-chain diseases related to complex III deficiency. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2009; 1793:181-5. [DOI: 10.1016/j.bbamcr.2008.06.004] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Revised: 05/27/2008] [Accepted: 06/04/2008] [Indexed: 11/16/2022]
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Dimauro S, Rustin P. A critical approach to the therapy of mitochondrial respiratory chain and oxidative phosphorylation diseases. Biochim Biophys Acta Mol Basis Dis 2008; 1792:1159-67. [PMID: 19026744 DOI: 10.1016/j.bbadis.2008.10.015] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Revised: 10/09/2008] [Accepted: 10/11/2008] [Indexed: 12/17/2022]
Abstract
Taking advantage of a series of questions raised by an association of patients with mitochondrial disease, this review, after a brief overview of basic concepts of mitochondrial bioenergetics and genetics, discusses the pros and cons of a number of practical options in the field of mitochondrial therapy. This makes it clear that, in contrast to the spectacular progress in our understanding of the biochemical and molecular bases of the mitochondrial diseases defined restrictively as disorders due to defects in the mitochondrial respiratory chain, we are still extremely limited in our ability to treat these conditions. We finally discussed the emerging genetic-based strategies that show some promise, even if much work remains to be done.
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Affiliation(s)
- Salvatore Dimauro
- Department of Neurology, Columbia University Medical Center, 313 Russ Berrie Medical Science Pavilion, 1150 St. Nicholas Avenue, New York, NY 10032, USA
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Bénit P, Goncalves S, Dassa EP, Brière JJ, Rustin P. The variability of the harlequin mouse phenotype resembles that of human mitochondrial-complex I-deficiency syndromes. PLoS One 2008; 3:e3208. [PMID: 18791645 PMCID: PMC2527683 DOI: 10.1371/journal.pone.0003208] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Accepted: 08/26/2008] [Indexed: 01/22/2023] Open
Abstract
Background Despite the considerable progress made in understanding the molecular bases of mitochondrial diseases, no effective treatments have been developed to date. Faithful animal models would be extremely helpful for designing such treatments. We showed previously that the Harlequin mouse phenotype was due to a specific mitochondrial complex I deficiency resulting from the loss of the Apoptosis Inducing Factor (Aif) protein. Methodology/Principal Findings Here, we conducted a detailed evaluation of the Harlequin mouse phenotype, including the biochemical abnormalities in various tissues. We observed highly variable disease expression considering both severity and time course progression. In each tissue, abnormalities correlated with the residual amount of the respiratory chain complex I 20 kDa subunit, rather than with residual Aif protein. Antioxidant enzyme activities were normal except in skeletal muscle, where they were moderately elevated. Conclusions/Significance Thus, the Harlequin mouse phenotype appears to result from mitochondrial respiratory chain complex I deficiency. Its features resemble those of human complex I deficiency syndromes. The Harlequin mouse holds promise as a model for developing treatments for complex I deficiency syndromes.
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Affiliation(s)
- Paule Bénit
- Inserm, U676, Hôpital Robert Debré, Paris, France
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Dassa EP, Paupe V, Gonçalves S, Rustin P. The mtDNA NARP mutation activates the actin-Nrf2 signaling of antioxidant defenses. Biochem Biophys Res Commun 2008; 368:620-4. [PMID: 18261463 DOI: 10.1016/j.bbrc.2008.01.125] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Accepted: 01/25/2008] [Indexed: 11/26/2022]
Abstract
An efficient handling of superoxides by antioxidant defenses is a crucial issue for cells with respiratory chain deficient mitochondria. We used human cultured skin fibroblasts to delineate the mechanism controlling the expression of antioxidant defenses in the case of a severe ATPase deficiency resulting from an 8993T>G mutation in the mitochondrial ATPase6 gene. We observed the nuclear translocation of the transcription factor Nrf2 associated with thinning of the actin stress fibers. The mobilization of the Nrf2 signaling pathway could be mimicked by a chemical blockade of the ATPase with a specific inhibitor, oligomycin. Interestingly enough, Nrf2 nuclear translocation was not observed in the case of a severe cytochrome oxidase deficiency, indicating that studying the status of this signaling pathway could throw some light on the importance of the oxidative insult associated with different respiratory chain defects.
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Affiliation(s)
- Emmanuel Philippe Dassa
- Inserm, U676, Hôpital Robert Debré, 48 Boulevard Serurier, Batiment Ecran, Paris F-75019, France
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Brown KA, Didion SP, Andresen JJ, Faraci FM. Effect of aging, MnSOD deficiency, and genetic background on endothelial function: evidence for MnSOD haploinsufficiency. Arterioscler Thromb Vasc Biol 2007; 27:1941-6. [PMID: 17556650 DOI: 10.1161/atvbaha.107.146852] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE The goal of this study was to compare vascular function, superoxide levels, and MnSOD protein expression in young (4 to 7 months) and old (22 to 24 months) MnSOD+/+ and MnSOD-deficient (MnSOD+/-) mice. METHODS AND RESULTS Relaxation of aorta in vitro to the endothelium-dependent dilator acetylcholine (ACh) was similar in young MnSOD+/+ (n=9) and young MnSOD+/- (n=6) mice. This response was impaired in old MnSOD+/+ (n=8) mice and old MnSOD+/- mice (n=14), with dysfunction being greater in old MnSOD-deficient mice (eg, 100 micromol/L ACh produced 77+/-3% [mean+/-SE], 77+/-3%, 70+/-4%, and 57+/-4% relaxation in young MnSOD+/+, young MnSOD+/-, old MnSOD+/+, and old MnSOD+/- mice, respectively). The endothelial dysfunction was similar in mice on both C57BL/6 and CD-1 genetic backgrounds. In contrast to ACh, responses to the endothelium-independent dilator sodium nitroprusside were enhanced in old MnSOD+/+ and MnSOD+/- mice compared with both groups of young mice (P<0.05). Superoxide levels, as measured using lucigenin-enhanced chemiluminescence, were increased more than 2-fold in old MnSOD+/- mice compared with old MnSOD+/+ and young mice (P<0.05). CONCLUSIONS These data provide the first direct evidence that MnSOD haploinsufficiency results in increased vascular oxidative stress and endothelial dysfunction with aging.
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Affiliation(s)
- Kathryn A Brown
- Departments of Pharmacology, Cardiovascular Center, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA
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Brière JJ, Favier J, Gimenez-Roqueplo AP, Rustin P. Tricarboxylic acid cycle dysfunction as a cause of human diseases and tumor formation. Am J Physiol Cell Physiol 2006; 291:C1114-20. [PMID: 16760265 DOI: 10.1152/ajpcell.00216.2006] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A renewed interest in tricarboxylic acid cycle enzymopathies has resulted from the report that, in addition to devastating encephalopathies, these can result in various types of tumors in human. We first review the major features of the cycle that may underlie this surprising variety of clinical features. After discussing the rare cases of encephalopathies associated with specific deficiencies of some of the tricarboxylic acid cycle enzyme, we finally examine the mechanism possibly causing tumor/cancer formation in the cases of mutations affecting fumarase or succinate dehydrogenase genes.
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Affiliation(s)
- Jean-Jacques Brière
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 676, Hôpital Robert Debré, Paris
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Peng TI, Yu PR, Chen JY, Wang HL, Wu HY, Wei YH, Jou MJ. Visualizing common deletion of mitochondrial DNA-augmented mitochondrial reactive oxygen species generation and apoptosis upon oxidative stress. Biochim Biophys Acta Mol Basis Dis 2006; 1762:241-55. [PMID: 16368227 DOI: 10.1016/j.bbadis.2005.10.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2005] [Revised: 10/17/2005] [Accepted: 10/19/2005] [Indexed: 01/05/2023]
Abstract
Common deletion (CD) 4977 bp of mitochondrial DNA (mtDNA) disrupt specifically mitochondrial complex I, IV and V on the electron transport chain (ETC) and is closely associated with wide spectrums of clinical manifestations. To quantitatively investigate how CD-induced ETC defect alters mitochondrial reactive oxygen species (mROS) generation as well as down stream apoptotic signaling, we employed an established array of human CD cytoplasmic hybrids (cybrids) harboring 0%-80% of CD. Pathological effects of CD on the mitochondria were visualized at single cell level by the application of fluorescent probes coupled with conventional and multiphoton imaging microscopy. Intriguingly, we observed CD-augmented mROS generation omitted "threshold effect". CD-augmented mROS generation was associated with depolarized mitochondrial membrane potential (DeltaPsi(m)). Upon oxidative stress, the amount of CD-augmented mROS generation was greatly enhanced to cause pathological apoptotic deterioration including opening of the mitochondrial permeability transition, cytochrome c release, phosphatidylserine externalization and DNA fragmentation. In addition, heterogeneous mitochondrial dysfunctions were found in cybrids containing 80% of CD (D cybrids), i.e., low sensitive-D (LS-D, roughly 80%) and a super sensitive-D (SS-D, 20%). As compared to LS-D, SS-D had higher resting mROS level but slightly hyperpolarized DeltaPsi(m). Upon H2O2 treatment, much faster generation of mROS was observed which induced a faster depolarization of DeltaPsi(m) and later apoptotic deterioration in SS-D. We proposed a dose-dependent, feed-forward and self-accelerating vicious cycle of mROS production might be initiated in CD-induced ETC defect without threshold effect. As CD-augmented mROS generation is obligated to cause an enhanced pathological apoptosis, precise detection of CD-augmented mROS generation and their degree of heterogeneity in single cells may serve as sensitive pathological indexes for early diagnosis, prognosis and treatment of CD-associated diseases.
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Affiliation(s)
- Tsung-I Peng
- Department of Neurology, Lin-Kou Medical Center, Chang Gung Memorial Hospital, Tao-Yuan, Taiwan
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Brière JJ, Favier J, Bénit P, El Ghouzzi V, Lorenzato A, Rabier D, Di Renzo MF, Gimenez-Roqueplo AP, Rustin P. Mitochondrial succinate is instrumental for HIF1alpha nuclear translocation in SDHA-mutant fibroblasts under normoxic conditions. Hum Mol Genet 2005; 14:3263-9. [PMID: 16195397 DOI: 10.1093/hmg/ddi359] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The genes encoding succinate dehydrogenase (SDH) subunits B, C and D, act as tumour suppressors in neuro-endocrine tissues. Tumour formation has been associated with succinate accumulation. In paraganglioma cells, two forms of SDHA (type I, II) were found which might preclude significant succinate accumulation in the case of a mutation in either form. In fibroblasts only SDHA type I is found. In these cells, SDHA type I mutation leads to SDH deficiency, succinate accumulation and hypoxia-inducible factor 1alpha(HIF1alpha) nuclear translocation. HIF1alpha nuclear translocation was not observed in ATPase-deficient fibroblasts with increased superoxide production and was found to be independent of cellular iron availability in SDHA-mutant cells. This suggests that neither superoxides nor iron were causative of HIF1alpha nuclear translocation. Conversely, alpha-ketoglutarate (alpha-KG) inhibits this nuclear translocation. Therefore, the pseudo-hypoxia pathway in SDH-deficient cells depends on the HIF1alphaprolyl hydroxylase product/substrate (succinate/alpha-KG) equilibrium. In SDH deficiency, organic acids thus appear instrumental in the HIF1alpha-dependent cascade suggesting a direct link between SDH and tumourigenesis.
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