1
|
Borrelli E, Bandello F, Boon CJF, Carelli V, Lenaers G, Reibaldi M, Sadda SR, Sadun AA, Sarraf D, Yu-Wai-Man P, Barboni P. Mitochondrial retinopathies and optic neuropathies: The impact of retinal imaging on modern understanding of pathogenesis, diagnosis, and management. Prog Retin Eye Res 2024; 101:101264. [PMID: 38703886 DOI: 10.1016/j.preteyeres.2024.101264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 03/18/2024] [Accepted: 04/26/2024] [Indexed: 05/06/2024]
Abstract
Advancements in ocular imaging have significantly broadened our comprehension of mitochondrial retinopathies and optic neuropathies by examining the structural and pathological aspects of the retina and optic nerve in these conditions. This article aims to review the prominent imaging characteristics associated with mitochondrial retinopathies and optic neuropathies, aiming to deepen our insight into their pathogenesis and clinical features. Preceding this exploration, the article provides a detailed overview of the crucial genetic and clinical features, which is essential for the proper interpretation of in vivo imaging. More importantly, we will provide a critical analysis on how these imaging modalities could serve as biomarkers for characterization and monitoring, as well as in guiding treatment decisions. However, these imaging methods have limitations, which will be discussed along with potential strategies to mitigate them. Lastly, the article will emphasize the potential advantages and future integration of imaging techniques in evaluating patients with mitochondrial eye disorders, considering the prospects of emerging gene therapies.
Collapse
Affiliation(s)
- Enrico Borrelli
- Department of Surgical Sciences, University of Turin, Turin, Italy; Department of Ophthalmology, "City of Health and Science" Hospital, Turin, Italy.
| | - Francesco Bandello
- Vita-Salute San Raffaele University, Milan, Italy; IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Camiel J F Boon
- Department of Ophthalmology, Amsterdam University Medical Centers, Amsterdam, the Netherlands; Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - Valerio Carelli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy; IRCCS Istituto delle Scienze Neurologiche di Bologna, Programma di Neurogenetica, Bologna, Italy
| | - Guy Lenaers
- Equipe MitoLab, Unité MitoVasc, INSERM U1083, Université d'Angers, 49933, Angers, France; Service de Neurologie, CHU d'Angers, 49100, Angers, France
| | - Michele Reibaldi
- Department of Surgical Sciences, University of Turin, Turin, Italy; Department of Ophthalmology, "City of Health and Science" Hospital, Turin, Italy
| | - Srinivas R Sadda
- Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Doheny Eye Institute, Los Angeles, CA, USA
| | - Alfredo A Sadun
- Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Doheny Eye Institute, Los Angeles, CA, USA
| | - David Sarraf
- Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Retinal Disorders and Ophthalmic Genetics Division, Stein Eye Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Patrick Yu-Wai-Man
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK; Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Institute of Ophthalmology, University College London, London, UK
| | - Piero Barboni
- IRCCS San Raffaele Scientific Institute, Milan, Italy; Studio Oculistico d'Azeglio, Bologna, Italy.
| |
Collapse
|
2
|
Del Dotto V, Musiani F, Baracca A, Solaini G. Variants in Human ATP Synthase Mitochondrial Genes: Biochemical Dysfunctions, Associated Diseases, and Therapies. Int J Mol Sci 2024; 25:2239. [PMID: 38396915 PMCID: PMC10889682 DOI: 10.3390/ijms25042239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/06/2024] [Accepted: 02/08/2024] [Indexed: 02/25/2024] Open
Abstract
Mitochondrial ATP synthase (Complex V) catalyzes the last step of oxidative phosphorylation and provides most of the energy (ATP) required by human cells. The mitochondrial genes MT-ATP6 and MT-ATP8 encode two subunits of the multi-subunit Complex V. Since the discovery of the first MT-ATP6 variant in the year 1990 as the cause of Neuropathy, Ataxia, and Retinitis Pigmentosa (NARP) syndrome, a large and continuously increasing number of inborn variants in the MT-ATP6 and MT-ATP8 genes have been identified as pathogenic. Variants in these genes correlate with various clinical phenotypes, which include several neurodegenerative and multisystemic disorders. In the present review, we report the pathogenic variants in mitochondrial ATP synthase genes and highlight the molecular mechanisms underlying ATP synthase deficiency that promote biochemical dysfunctions. We discuss the possible structural changes induced by the most common variants found in patients by considering the recent cryo-electron microscopy structure of human ATP synthase. Finally, we provide the state-of-the-art of all therapeutic proposals reported in the literature, including drug interventions targeting mitochondrial dysfunctions, allotopic gene expression- and nuclease-based strategies, and discuss their potential translation into clinical trials.
Collapse
Affiliation(s)
- Valentina Del Dotto
- Laboratory of Biochemistry and Mitochondrial Pathophysiology, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (V.D.D.); (G.S.)
| | - Francesco Musiani
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology (FABIT), University of Bologna, 40127 Bologna, Italy;
| | - Alessandra Baracca
- Laboratory of Biochemistry and Mitochondrial Pathophysiology, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (V.D.D.); (G.S.)
| | - Giancarlo Solaini
- Laboratory of Biochemistry and Mitochondrial Pathophysiology, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy; (V.D.D.); (G.S.)
| |
Collapse
|
3
|
Gao Y, Guo L, Wang F, Wang Y, Li P, Zhang D. Development of mitochondrial gene-editing strategies and their potential applications in mitochondrial hereditary diseases: a review. Cytotherapy 2024; 26:11-24. [PMID: 37930294 DOI: 10.1016/j.jcyt.2023.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 10/12/2023] [Accepted: 10/13/2023] [Indexed: 11/07/2023]
Abstract
Mitochondrial DNA (mtDNA) is a critical genome contained within the mitochondria of eukaryotic cells, with many copies present in each mitochondrion. Mutations in mtDNA often are inherited and can lead to severe health problems, including various inherited diseases and premature aging. The lack of efficient repair mechanisms and the susceptibility of mtDNA to damage exacerbate the threat to human health. Heteroplasmy, the presence of different mtDNA genotypes within a single cell, increases the complexity of these diseases and requires an effective editing method for correction. Recently, gene-editing techniques, including programmable nucleases such as restriction endonuclease, zinc finger nuclease, transcription activator-like effector nuclease, clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeats-associated 9 and base editors, have provided new tools for editing mtDNA in mammalian cells. Base editors are particularly promising because of their high efficiency and precision in correcting mtDNA mutations. In this review, we discuss the application of these techniques in mitochondrial gene editing and their limitations. We also explore the potential of base editors for mtDNA modification and discuss the opportunities and challenges associated with their application in mitochondrial gene editing. In conclusion, this review highlights the advancements, limitations and opportunities in current mitochondrial gene-editing technologies and approaches. Our insights aim to stimulate the development of new editing strategies that can ultimately alleviate the adverse effects of mitochondrial hereditary diseases.
Collapse
Affiliation(s)
- Yanyan Gao
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Linlin Guo
- The Affiliated Cardiovascular Hospital of Qingdao University, Qingdao University, Qingdao, China
| | - Fei Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Yin Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Peifeng Li
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Dejiu Zhang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China.
| |
Collapse
|
4
|
Finsterer J. Neuropathy, Ataxia, and Retinitis Pigmentosa Syndrome. J Clin Neuromuscul Dis 2023; 24:140-146. [PMID: 36809201 DOI: 10.1097/cnd.0000000000000422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVES To provide an overview about the phenotype, genotype, treatment, and outcome of neuropathy, ataxia, and retinitis pigmentosa (NARP) syndrome. METHODS Systematic review by application of appropriate search terms. RESULTS NARP syndrome is a syndromic mitochondrial disorder due to pathogenic variants in MT-ATP6. The canonical phenotypic features of NARP syndrome include proximal muscle weakness, axonal neuropathy, cerebellar ataxia, and retinitis pigmentosa. Noncanonical phenotypic features in NARP include epilepsy, cerebral or cerebellar atrophy, optic atrophy, cognitive impairment, dementia, sleep apnea syndrome, hearing impairment, renal insufficiency, and diabetes. So far, 10 pathogenic variants in MT-ATP6 have been associated with NARP, NARP-like syndrome, or NARP/maternally inherited Leigh overlap syndrome. Most pathogenic MT-ATP6 variants are missense, but a few truncating pathogenic variants have been reported. The most common variant responsible for NARP is the transversion m.8993T>G. Only symptomatic treatment for NARP syndrome is available. In most of the cases, patients die prematurely. Patients with late-onset NARP survive longer. CONCLUSIONS NARP is a rare, syndromic, monogenic mitochondrial disorder due to pathogenic variants in MT-ATP6. The nervous system and the eyes are most commonly affected. Although only symptomatic treatment is available, the outcome is usually fair.
Collapse
|
5
|
Wang L, Yang Z, He X, Pu S, Yang C, Wu Q, Zhou Z, Cen X, Zhao H. Mitochondrial protein dysfunction in pathogenesis of neurological diseases. Front Mol Neurosci 2022; 15:974480. [PMID: 36157077 PMCID: PMC9489860 DOI: 10.3389/fnmol.2022.974480] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 08/08/2022] [Indexed: 11/21/2022] Open
Abstract
Mitochondria are essential organelles for neuronal function and cell survival. Besides the well-known bioenergetics, additional mitochondrial roles in calcium signaling, lipid biogenesis, regulation of reactive oxygen species, and apoptosis are pivotal in diverse cellular processes. The mitochondrial proteome encompasses about 1,500 proteins encoded by both the nuclear DNA and the maternally inherited mitochondrial DNA. Mutations in the nuclear or mitochondrial genome, or combinations of both, can result in mitochondrial protein deficiencies and mitochondrial malfunction. Therefore, mitochondrial quality control by proteins involved in various surveillance mechanisms is critical for neuronal integrity and viability. Abnormal proteins involved in mitochondrial bioenergetics, dynamics, mitophagy, import machinery, ion channels, and mitochondrial DNA maintenance have been linked to the pathogenesis of a number of neurological diseases. The goal of this review is to give an overview of these pathways and to summarize the interconnections between mitochondrial protein dysfunction and neurological diseases.
Collapse
Affiliation(s)
- Liang Wang
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Ziyun Yang
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Hospital of Sichuan University, Chengdu, China
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Xiumei He
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Shiming Pu
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Cheng Yang
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Qiong Wu
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Zuping Zhou
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
| | - Xiaobo Cen
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Hongxia Zhao
- School of Life Sciences, Guangxi Normal University, Guilin, China
- Guangxi Universities, Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin, China
- Research Center for Biomedical Sciences, Guangxi Normal University, Guilin, China
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| |
Collapse
|
6
|
Juaristi L, Irigoyen C, Quiroga J. NEUROPATHY, ATAXIA, AND RETINITIS PIGMENTOSA SYNDROME: A MULTIDISCIPLINARY DIAGNOSIS. Retin Cases Brief Rep 2021; 15:486-489. [PMID: 30346353 PMCID: PMC8219086 DOI: 10.1097/icb.0000000000000835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To report a case of neuropathy, ataxia, and retinitis pigmentosa syndrome, a rare and undiagnosed disease in ophthalmology due to the need for multidisciplinary evaluation. METHODS Multimodal testing was performed, including neurologic, ophthalmologic, and genetic assessments. The neurologic tests comprised electromyogram and muscle biopsy; the ophthalmologic examination consisted of slit-lamp and fundus examinations, optical coherence tomography, visual field testing, and electrophysiology tests such as a full-field electroretinogram and multifocal electroretinogram; and genetic tests were performed for spinocerebellar ataxia. In addition, the patient underwent magnetic resonance imaging, an electrocardiogram, cerebrospinal fluid analysis with lactate levels, and a blood workup including antineuronal, antithyroid peroxidase, antinuclear, antimitochondrial, and antitransglutaminase antibodies and fat-soluble vitamins (A, D, E, K). RESULTS The ocular fundus examination showed bone spicules with retinal pigment epithelium alteration, optic nerve pallor, and arterial attenuation. Optical coherence tomography demonstrated macular atrophy. Visual field testing revealed concentric reduction. Electrophysiology examinations showed involvement of rods and cones in both eyes. The muscle biopsy was compatible with mitochondrial disease, and electromyogram demonstrated sensory axonal damage. However, genetic tests for spinocerebellar ataxia were negative. Magnetic resonance imaging showed cerebellar atrophy, whereas the electrocardiogram did not detect any abnormalities. Cerebrospinal fluid lactate levels were above normal but antibody levels in blood were normal. CONCLUSION This is the first report of macular atrophy demonstrated by optical coherence tomography in a patient with neuropathy, ataxia, and retinitis pigmentosa syndrome. For the diagnosis, a multidisciplinary team including a neurologist, a geneticist, and an ophthalmologist was essential. Patients with suspected mitochondrial disease could greatly benefit from an ophthalmology examination like that conducted in this case because it was the key factor that led to the suspicion of syndromic disease, and ultimately the diagnosis.
Collapse
Affiliation(s)
- Leire Juaristi
- Department of Ophthalmology, Donostia University Hospital, Donostia - San-Sebastian, Spain
| | | | | |
Collapse
|
7
|
Carrella S, Massa F, Indrieri A. The Role of MicroRNAs in Mitochondria-Mediated Eye Diseases. Front Cell Dev Biol 2021; 9:653522. [PMID: 34222230 PMCID: PMC8249810 DOI: 10.3389/fcell.2021.653522] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 05/20/2021] [Indexed: 12/15/2022] Open
Abstract
The retina is among the most metabolically active tissues with high-energy demands. The peculiar distribution of mitochondria in cells of retinal layers is necessary to assure the appropriate energy supply for the transmission of the light signal. Photoreceptor cells (PRs), retinal pigment epithelium (RPE), and retinal ganglion cells (RGCs) present a great concentration of mitochondria, which makes them particularly sensitive to mitochondrial dysfunction. To date, visual loss has been extensively correlated to defective mitochondrial functions. Many mitochondrial diseases (MDs) show indeed neuro-ophthalmic manifestations, including retinal and optic nerve phenotypes. Moreover, abnormal mitochondrial functions are frequently found in the most common retinal pathologies, i.e., glaucoma, age-related macular degeneration (AMD), and diabetic retinopathy (DR), that share clinical similarities with the hereditary primary MDs. MicroRNAs (miRNAs) are established as key regulators of several developmental, physiological, and pathological processes. Dysregulated miRNA expression profiles in retinal degeneration models and in patients underline the potentiality of miRNA modulation as a possible gene/mutation-independent strategy in retinal diseases and highlight their promising role as disease predictive or prognostic biomarkers. In this review, we will summarize the current knowledge about the participation of miRNAs in both rare and common mitochondria-mediated eye diseases. Definitely, given the involvement of miRNAs in retina pathologies and therapy as well as their use as molecular biomarkers, they represent a determining target for clinical applications.
Collapse
Affiliation(s)
| | - Filomena Massa
- Telethon Institute of Genetics and Medicine, Naples, Italy
| | - Alessia Indrieri
- Telethon Institute of Genetics and Medicine, Naples, Italy.,Institute for Genetic and Biomedical Research, National Research Council (CNR), Milan, Italy
| |
Collapse
|
8
|
Zhunina OA, Yabbarov NG, Grechko AV, Yet SF, Sobenin IA, Orekhov AN. Neurodegenerative Diseases Associated with Mitochondrial DNA Mutations. Curr Pharm Des 2020; 26:103-109. [DOI: 10.2174/1381612825666191122091320] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 11/19/2019] [Indexed: 01/23/2023]
Abstract
Mitochondrial dysfunction underlies several human chronic pathologies, including cardiovascular
disorders, cancers and neurodegenerative diseases. Impaired mitochondrial function associated with oxidative
stress can be a result of both nuclear and mitochondrial DNA (mtDNA) mutations. Neurological disorders associated
with mtDNA mutations include mitochondrial encephalomyopathy, chronic progressive external ophthalmoplegia,
neurogenic weakness, and Leigh syndrome. Moreover, mtDNA mutations were shown to play a role in the
development of Parkinson and Alzheimer’s diseases. In this review, current knowledge on the distribution and
possible roles of mtDNA mutations in the onset and development of various neurodegenerative diseases, with
special focus on Parkinson’s and Alzheimer’s diseases has been discussed.
Collapse
Affiliation(s)
- Olga A. Zhunina
- Russian Research Center for Molecular Diagnostics and Therapy, Simferopolsky Blvd., 8, 117149, Moscow, Russian Federation
| | - Nikita G. Yabbarov
- Russian Research Center for Molecular Diagnostics and Therapy, Simferopolsky Blvd., 8, 117149, Moscow, Russian Federation
| | - Andrey V. Grechko
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, 14-3 Solyanka Street, 109240, Moscow, Russian Federation
| | - Shaw-Fang Yet
- Institute of Cellular and System Medicine, National Health Research Institutes, 35 Keyan Road, Zhunan Town, Miaoli County 35053, Taiwan
| | - Igor A. Sobenin
- Laboratory of Medical Genetics, National Medical Research Center of Cardiology, 15A 3rd Cherepkovskaya Street, Moscow 121552, Russian Federation
| | - Alexander N. Orekhov
- Institute of Human Morphology, 3 Tsyurupa Street, Moscow 117418, Russian Federation
| |
Collapse
|
9
|
Liu G, Shen X, Sun Y, Lv Q, Li Y, Du A. Heteroplasmy and phenotype spectrum of the mitochondrial tRNA Leu (UUR) gene m.3243A>G mutation in seven Han Chinese families. J Neurol Sci 2020; 408:116562. [PMID: 31722256 DOI: 10.1016/j.jns.2019.116562] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 11/03/2019] [Accepted: 11/04/2019] [Indexed: 01/06/2023]
Abstract
The m.3243A > G mutation in the mitochondrial tRNALeu (UUR) gene is associated with a variety of phenotypic heterogeneity. The clinical spectrum and phenotypic-genotypic correlations in the Chinese patients are poorly understood. In the present study, we reported the clinical and genetic characterization, as well as haplogroups of seven Han Chinese families carrying the m.3243A > G mutation. Of the 39 matrilineal individuals, five suffered from mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS), two had life-threatening mitochondrial myopathy (LTMM), and one patient had neuropathy, ataxia, and retinitis pigmentosa (NARP)-like syndrome. The LTMM and NARP like syndromes enriched the phenotypic profile of the m.3243A > G mutation. The heteroplasmy of the m.3243A > G mutation ranged from 16% to 59% in MELAS, 29% to 79% in LTMM, and 57% in a NARP-like syndrome patient. The levels ranged from 0% to 14% in patients that manifested with pure diabetes and pure hearing loss, and 0% to 5% in 13 normal family members. However, we particularly noticed heteroplasmy in four asymptomatic individuals in one LTMM family carried the heteroplasmy mutation ranged from 22% to 78%, implying that there were other modifying factors in this family. The modulation of the phenotype of mtDNA mutations requires further investigation.
Collapse
Affiliation(s)
- Gailing Liu
- Department of Neurology, Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200336, China
| | - Xiya Shen
- Department of Neurology, Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200336, China
| | - Yongan Sun
- Department of Neurology, Perking University First Hospital, Beijing 100034, China
| | - Qing Lv
- Department of Neurology, Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200336, China
| | - Yuanyuan Li
- Department of Neurology, Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200336, China
| | - Ailian Du
- Department of Neurology, Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200336, China; Department of Neurology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China.
| |
Collapse
|
10
|
Shi Q, Luan Q, Wang X, Cai Y. Correlation study on mtDNA polymorphisms as potential risk factors in aggressive periodontitis by NGS. Oral Dis 2019; 26:401-408. [PMID: 31715075 DOI: 10.1111/odi.13231] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 10/11/2019] [Accepted: 11/06/2019] [Indexed: 12/12/2022]
Abstract
OBJECTIVES Using next-generation sequencing (NGS) to determine whether aggressive periodontitis is associated with specific mitochondrial polymorphisms. MATERIALS AND METHODS A total of 165 unrelated Han Chinese were enrolled in the study. We analyzed the mitochondrial DNA (mtDNA) in 97 patients with aggressive periodontitis and 68 healthy controls by NGS. The mitochondrial DNA was L-PCR-amplified and subsequently sequenced by an Illumina Genome Analyzer (NGS). Chi-square tests were used to assess the differences between the two groups. In cases of significant difference, multivariate logistic regression models were further used to analyze the association between mtDNA polymorphisms and aggressive periodontitis. RESULTS Significant association was observed between aggressive periodontitis and eight mitochondrial polymorphisms: "8860G-10400C" (OR = 2.828, p = .002), "8701A" (OR = 2.308, p = .005), "12705C-10398A" (OR = 2.683, p = .002), "9540C" (OR = 3.838, p = .001) and "10873T-15043G" (OR = 4.375, p = .001). CONCLUSIONS The pathogenesis of aggressive periodontitis is complicated, and its heredity is not well characterized. Our study was the first to use next-generation sequencing and found that 8860G-10400C, 8701A, 12705C-10398A, 9540C, and 10873T-15043G are associated with aggressive periodontitis in the Han Chinese population.
Collapse
Affiliation(s)
- Qiao Shi
- Department of Periodontology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Peking University School and Hospital of Stomatology, Beijing, China
| | - Qingxian Luan
- Department of Periodontology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Peking University School and Hospital of Stomatology, Beijing, China
| | - Xiaoxuan Wang
- Department of Periodontology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Peking University School and Hospital of Stomatology, Beijing, China
| | - Yu Cai
- Department of Periodontology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Peking University School and Hospital of Stomatology, Beijing, China.,Central Laboratory, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Peking University School and Hospital of Stomatology, Beijing, China
| |
Collapse
|
11
|
Cardiovascular Manifestations of Mitochondrial Disease. BIOLOGY 2019; 8:biology8020034. [PMID: 31083569 PMCID: PMC6628328 DOI: 10.3390/biology8020034] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 04/13/2019] [Accepted: 04/22/2019] [Indexed: 02/06/2023]
Abstract
Genetic mitochondrial cardiomyopathies are uncommon causes of heart failure that may not be seen by most physicians. However, the prevalence of mitochondrial DNA mutations and somatic mutations affecting mitochondrial function are more common than previously thought. In this review, the pathogenesis of genetic mitochondrial disorders causing cardiovascular disease is reviewed. Treatment options are presently limited to mostly symptomatic support, but preclinical research is starting to reveal novel approaches that may lead to better and more targeted therapies in the future. With better understanding and clinician education, we hope to improve clinician recognition and diagnosis of these rare disorders in order to improve ongoing care of patients with these diseases and advance research towards discovering new therapeutic strategies to help treat these diseases.
Collapse
|
12
|
Ganetzky RD, Stendel C, McCormick EM, Zolkipli-Cunningham Z, Goldstein AC, Klopstock T, Falk MJ. MT-ATP6 mitochondrial disease variants: Phenotypic and biochemical features analysis in 218 published cases and cohort of 14 new cases. Hum Mutat 2019; 40:499-515. [PMID: 30763462 PMCID: PMC6506718 DOI: 10.1002/humu.23723] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 01/29/2019] [Accepted: 02/11/2019] [Indexed: 01/30/2023]
Abstract
Mitochondrial complex V (CV) generates cellular energy as adenosine triphosphate (ATP). Mitochondrial disease caused by the m.8993T>G pathogenic variant in the CV subunit gene MT-ATP6 was among the first described human mitochondrial DNA diseases. Due to a lack of clinically available functional assays, validating the definitive pathogenicity of additional MT-ATP6 variants remains challenging. We reviewed all reportedMT-ATP6 disease cases ( n = 218) to date, to assess for MT-ATP6 variants, heteroplasmy levels, and inheritance correlation with clinical presentation and biochemical findings. We further describe the clinical and biochemical features of a new cohort of 14 kindreds with MT-ATP6 variants of uncertain significance. Despite extensive overlap in the heteroplasmy levels of MT-ATP6 variant carriers with and without a wide range of clinical symptoms, previously reported symptomatic subjects had significantly higher heteroplasmy load (p = 2.2 x 10-16 ). Pathogenic MT-ATP6 variants resulted in diverse biochemical features. The most common findings were reduced ATP synthesis rate, preserved ATP hydrolysis capacity, and abnormally increased mitochondrial membrane potential. However, no single biochemical feature was universally observed. Extensive heterogeneity exists among both clinical and biochemical features of distinct MT-ATP6 variants. Improved mechanistic understanding and development of consistent biochemical diagnostic analyses are needed to permit accurate pathogenicity assessment of variants of uncertain significance in MT-ATP6.
Collapse
Affiliation(s)
- Rebecca D. Ganetzky
- Department of Pediatrics, Mitochondrial Medicine Frontier Program, Division of Human Genetics
Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
- Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
USA
| | - Claudia Stendel
- Department of Psychiatry, Ludwig Maximilians University of Munich, Munich, Germany
| | - Elizabeth M. McCormick
- Department of Pediatrics, Mitochondrial Medicine Frontier Program, Division of Human Genetics
Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
| | - Zarazuela Zolkipli-Cunningham
- Department of Pediatrics, Mitochondrial Medicine Frontier Program, Division of Human Genetics
Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
- Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
USA
| | - Amy C. Goldstein
- Department of Pediatrics, Mitochondrial Medicine Frontier Program, Division of Human Genetics
Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
- Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
USA
| | - Thomas Klopstock
- Department of Neurology, Ludwig Maximilians University of Munich, Munich, Germany
| | - Marni J. Falk
- Department of Pediatrics, Mitochondrial Medicine Frontier Program, Division of Human Genetics
Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
- Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
USA
| |
Collapse
|
13
|
Banerjee A, Lindenmair A, Hennerbichler S, Steindorf P, Steinborn R, Kozlov AV, Redl H, Wolbank S, Weidinger A. Cellular and Site-Specific Mitochondrial Characterization of Vital Human Amniotic Membrane. Cell Transplant 2019; 27:3-11. [PMID: 29562784 PMCID: PMC6434485 DOI: 10.1177/0963689717735332] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Over a century ago, clinicians started to use the human amniotic membrane for coverage of wounds and burn injuries. To date, literally thousands of different clinical applications exist for this biomaterial almost exclusively in a decellularized or denuded form. Recent reconsiderations for the use of vital human amniotic membrane for clinical applications would take advantage of the versatile cells of embryonic origin including the entirety of their cell organelles. Recently, more and more evidence was found, showing mitochondria to be involved in most fundamental cellular processes, such as differentiation and cell death. In this study, we focused on specific properties of mitochondria of vital human amniotic membrane and characterized bioenergetical parameters of 2 subregions of the human amniotic membrane, the placental and reflected amnion. We found significantly different levels of adenosine triphosphate (ATP) and extracellular reactive oxygen species, concentrations of succinate dehydrogenase, and lactate upon inhibition of ATP synthase in placental and reflected amnion. We also found significantly different rates of mitochondrial respiration in isolated human amniotic epithelial cells and human amniotic mesenchymal stromal cells, according to the subregions. Differences in metabolic activities were inversely related to mitochondrial DNA copy numbers in isolated cells of placental and reflected amnion. Based on significant differences of several key parameters of energy metabolism in 2 subregions of vital amnion, we propose that these metabolic differences of vital placental and reflected amnion could have critical impact on therapeutic applications. Inclusion of region-specific metabolic properties could optimize and fine-tune the clinical application of the human amniotic membrane and improve the outcome significantly.
Collapse
Affiliation(s)
- Asmita Banerjee
- 1 Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria.,2 Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Andrea Lindenmair
- 2 Austrian Cluster for Tissue Regeneration, Vienna, Austria.,3 Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA, Linz, Austria
| | - Simone Hennerbichler
- 2 Austrian Cluster for Tissue Regeneration, Vienna, Austria.,4 Red Cross Blood Transfusion Service for Upper Austria, Linz, Austria
| | - Philipp Steindorf
- 5 Genomics Core Facility, VetCore, University of Veterinary Medicine, Vienna, Austria
| | - Ralf Steinborn
- 5 Genomics Core Facility, VetCore, University of Veterinary Medicine, Vienna, Austria
| | - Andrey V Kozlov
- 1 Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria.,2 Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Heinz Redl
- 1 Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria.,2 Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Susanne Wolbank
- 1 Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria.,2 Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Adelheid Weidinger
- 1 Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria.,2 Austrian Cluster for Tissue Regeneration, Vienna, Austria
| |
Collapse
|
14
|
Guo Y, Zhang Y, Li F, Liu P, Liu Y, Yang C, Song J, Zhang N, Chen Z. The biochemical characterization of a missense mutation m.8914C>T in ATP6 gene associated with mitochondrial encephalomyopathy. Int J Dev Neurosci 2018; 71:172-174. [PMID: 30273650 DOI: 10.1016/j.ijdevneu.2018.09.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 08/21/2018] [Accepted: 09/23/2018] [Indexed: 12/14/2022] Open
Abstract
Mutations in ATP6 gene are frequent causes of mitochondrial encephalomyopathies. ATP6 gene encodes one subunit of complexⅤ. The present study described a missense mutation in ATP6 gene in a 8-year-old Chinese boy with mitochondrial encephalomyopathy. We identified one missense mutation in ATP6 gene (m.8914C>T) by mitochondrial DNA sequencing. This mutation altered the amino acid proline in serine, and alterative protein is predicted to be harmful. The mutation load in blood sample of patient is 59.49%. Activity of all mitochondrial complexes in blood are normal, however, the total function of mitochondrial oxidative phosphorylation were declined (including pathwayⅠ, pathwayⅡ and pathwayⅣ). The missense mutation (m.8914C>T) in ATP6 gene could result in abnormal function of complexV and is related with mitochondrial encephalomyopathy.
Collapse
Affiliation(s)
- Ya Guo
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong, 266000, PR China.
| | - Yu Zhang
- Ophthalmology Department of Qingdao Municipal Hospital, No. 1 Jiaozhou Road, Shandong, 266000, PR China.
| | - Fei Li
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong, 266000, PR China.
| | - Peipei Liu
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong, 266000, PR China.
| | - Yedan Liu
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong, 266000, PR China.
| | - Chengqing Yang
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong, 266000, PR China.
| | - Jie Song
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong, 266000, PR China.
| | - Na Zhang
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong, 266000, PR China.
| | - Zongbo Chen
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong, 266000, PR China.
| |
Collapse
|
15
|
Dautant A, Meier T, Hahn A, Tribouillard-Tanvier D, di Rago JP, Kucharczyk R. ATP Synthase Diseases of Mitochondrial Genetic Origin. Front Physiol 2018; 9:329. [PMID: 29670542 PMCID: PMC5893901 DOI: 10.3389/fphys.2018.00329] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 03/15/2018] [Indexed: 01/30/2023] Open
Abstract
Devastating human neuromuscular disorders have been associated to defects in the ATP synthase. This enzyme is found in the inner mitochondrial membrane and catalyzes the last step in oxidative phosphorylation, which provides aerobic eukaryotes with ATP. With the advent of structures of complete ATP synthases, and the availability of genetically approachable systems such as the yeast Saccharomyces cerevisiae, we can begin to understand these molecular machines and their associated defects at the molecular level. In this review, we describe what is known about the clinical syndromes induced by 58 different mutations found in the mitochondrial genes encoding membrane subunits 8 and a of ATP synthase, and evaluate their functional consequences with respect to recently described cryo-EM structures.
Collapse
Affiliation(s)
- Alain Dautant
- Institut de Biochimie et Génétique Cellulaires, Centre National de la Recherche Scientifique UMR 5095, Université de Bordeaux, Bordeaux, France
| | - Thomas Meier
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Alexander Hahn
- Department of Structural Biology, Max-Planck-Institute of Biophysics, Frankfurt, Germany
| | - Déborah Tribouillard-Tanvier
- Institut de Biochimie et Génétique Cellulaires, Centre National de la Recherche Scientifique UMR 5095, Université de Bordeaux, Bordeaux, France
| | - Jean-Paul di Rago
- Institut de Biochimie et Génétique Cellulaires, Centre National de la Recherche Scientifique UMR 5095, Université de Bordeaux, Bordeaux, France
| | - Roza Kucharczyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| |
Collapse
|
16
|
Maalej M, Kammoun T, Alila-Fersi O, Kharrat M, Ammar M, Felhi R, Mkaouar-Rebai E, Keskes L, Hachicha M, Fakhfakh F. Cytochrome C oxydase deficiency: SURF1 gene investigation in patients with Leigh syndrome. Biochem Biophys Res Commun 2018; 497:1043-1048. [PMID: 29481804 DOI: 10.1016/j.bbrc.2018.02.169] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 02/22/2018] [Indexed: 01/26/2023]
Abstract
Leigh syndrome (LS) is a rare progressive neurodegenerative disorder occurring in infancy. The most common clinical signs reported in LS are growth retardation, optic atrophy, ataxia, psychomotor retardation, dystonia, hypotonia, seizures and respiratory disorders. The paper reported a manifestation of 3 Tunisian patients presented with LS syndrome. The aim of this study is the MT[HYPHEN]ATP6 and SURF1 gene screening in Tunisian patients affected with classical Leigh syndrome and the computational investigation of the effect of detected mutations on its structure and functions by clinical and bioinformatics analyses. After clinical investigations, three Tunisian patients were tested for mutations in both MT-ATP6 and SURF1 genes by direct sequencing followed by in silico analyses to predict the effects of sequence variation. The result of mutational analysis revealed the absence of mitochondrial mutations in MT-ATP6 gene and the presence of a known homozygous splice site mutation c.516-517delAG in sibling patients added to the presence of a novel double het mutations in LS patient (c.752-18 A > C/c. c.751 + 16G > A). In silico analyses of theses intronic variations showed that it could alters splicing processes as well as SURF1 protein translation. Leigh syndrome (LS) is a rare progressive neurodegenerative disorder occurring in infancy. The most common clinical signs reported in LS are growth retardation, optic atrophy, ataxia, psychomotor retardation, dystonia, hypotonia, seizures and respiratory disorders. The paper reported a manifestation of 3 Tunisian patients presented with LS syndrome. The aim of this study is MT-ATP6 and SURF1 genes screening in Tunisian patients affected with classical Leigh syndrome and the computational investigation of the effect of detected mutations on its structure and functions. After clinical investigations, three Tunisian patients were tested for mutations in both MT-ATP6 and SURF1 genes by direct sequencing followed by in silico analysis to predict the effects of sequence variation. The result of mutational analysis revealed the absence of mitochondrial mutations in MT-ATP6 gene and the presence of a known homozygous splice site mutation c.516-517delAG in sibling patients added to the presence of a novel double het mutations in LS patient (c.752-18 A>C/ c.751+16G>A). In silico analysis of theses intronic vaiations showed that it could alters splicing processes as well as SURF1 protein translation.
Collapse
Affiliation(s)
- Marwa Maalej
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia.
| | - Thouraya Kammoun
- Service de Pédiatrie, C.H.U. Hedi Chaker, University of Sfax, Tunisia
| | - Olfa Alila-Fersi
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia
| | - Marwa Kharrat
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia
| | - Marwa Ammar
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia
| | - Rahma Felhi
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia
| | - Emna Mkaouar-Rebai
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia
| | - Leila Keskes
- Laboratory of Human Molecular Genetics, Faculty of Medicine of Sfax, University of Sfax, Tunisia
| | - Mongia Hachicha
- Service de Pédiatrie, C.H.U. Hedi Chaker, University of Sfax, Tunisia
| | - Faiza Fakhfakh
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia.
| |
Collapse
|
17
|
Mitochondrial dysfunction underlying outer retinal diseases. Mitochondrion 2017; 36:66-76. [PMID: 28365408 DOI: 10.1016/j.mito.2017.03.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 03/06/2017] [Accepted: 03/27/2017] [Indexed: 01/21/2023]
Abstract
Dysfunction of photoreceptors, retinal pigment epithelium (RPE) or both contribute to the initiation and progression of several outer retinal disorders. Disrupted Müller glia function might additionally subsidize to these diseases. Mitochondrial malfunctioning is importantly associated with outer retina pathologies, which can be classified as primary and secondary mitochondrial disorders. This review highlights the importance of oxidative stress and mitochondrial DNA damage, underlying outer retinal disorders. Indeed, the metabolically active photoreceptors/RPE are highly prone to these hallmarks of mitochondrial dysfunction, indicating that mitochondria represent a weak link in the antioxidant defenses of outer retinal cells.
Collapse
|
18
|
Panosyan FB, Tawil R, Herrmann DN. Episodic weakness and Charcot-marie-tooth disease due to a mitochondrial MT-ATP6 mutation. Muscle Nerve 2017; 55:922-927. [PMID: 27783406 DOI: 10.1002/mus.25453] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2016] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Episodic muscle weakness is the hallmark of a heterogeneous group of disorders known as periodic paralysis. A majority are due to single nucleotide mutations causing membrane depolarization. METHODS We report 2 family members with chronic, slowly progressive, distal axonal neuropathy, or Charcot-Marie-Tooth disease type 2 (CMT2) and episodic weakness resembling periodic paralysis. RESULTS Next generation sequencing (NGS) identified a mitochondrial MT-ATP6 mutation m.9185T>C (p.Leu220Pro) in both patients, consistent with a previous report of an association with this phenotype. The episodic weakness has been responsive to acetazolamide therapy for a few decades. By contrast, the underlying axonal neuropathy is quite progressive despite treatment with acetazolamide. CONCLUSIONS Mitochondrial DNA mutations should be considered in patients with a history of episodic weakness and axonal inherited neuropathy (CMT2). The episodic weakness is responsive to acetazolamide therapy, and electrophysiological testing for periodic paralysis with a long exercise protocol is negative in these cases. Muscle Nerve 55: 922-927, 2017.
Collapse
Affiliation(s)
- Francis B Panosyan
- Department of Neurology, University of Rochester Medical Center, Box 673, 601 Elmwood Avenue, Rochester, New York, 14642, USA
| | - Rabi Tawil
- Department of Neurology, University of Rochester Medical Center, Box 673, 601 Elmwood Avenue, Rochester, New York, 14642, USA
| | - David N Herrmann
- Department of Neurology, University of Rochester Medical Center, Box 673, 601 Elmwood Avenue, Rochester, New York, 14642, USA
| |
Collapse
|
19
|
Finsterer J, Zarrouk-Mahjoub S. Mitochondrial multiorgan disorder syndrome score generated from definite mitochondrial disorders. Neuropsychiatr Dis Treat 2017; 13:2569-2579. [PMID: 29062232 PMCID: PMC5638572 DOI: 10.2147/ndt.s149067] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVES Mitochondrial disorders (MIDs) frequently present as mitochondrial multiorgan disorder syndrome (MIMODS) at onset or evolve into MIMODS during the course. This study aimed to find which organs and/or tissues are most frequently affected by MIMODS, which are the most frequent abnormalities within an affected organ, whether there are typical MIMODS patterns, and to generate an MIMODS score to assess the diagnostic probability for an MID. METHODS This is a retrospective evaluation of clinical, biochemical, and genetic investigations of adult patients with definite MIDs. A total of 36 definite MID patients, 19 men and 17 women, aged 29-82 years were included in this study. The diagnosis was based on genetic testing (n=21), on biochemical investigations (n=17), or on both (n=2). RESULTS The number of organs most frequently affected was 4 ranging from 1 to 9. MIMODS was diagnosed in 97% of patients. The organs most frequently affected were the muscle (97%), central nervous system (CNS; 72%), endocrine glands (69%), heart (58%), intestines (55%), and peripheral nerves (50%). The most frequent CNS abnormalities were leukoencephalopathy, prolonged visually evoked potentials, and atrophy. The most frequent endocrine abnormalities included thyroid dysfunction, short stature, and diabetes. The most frequent cardiac abnormalities included arrhythmias, systolic dysfunction, and hypertrophic cardiomyopathy. The most frequent MIMODS patterns were encephalomyopathy, encephalo-myo-endocrinopathy, and encepalo-myo-endocrino-cardiopathy. The mean ± 2SD MIMODS score was 35.97±27.6 (range =11-71). An MIMODS score >10 was regarded as indicative of an MID. CONCLUSION Adult MIDs manifest as MIMODS in the vast majority of the cases. The organs most frequently affected in MIMODS are muscles, CNS, endocrine glands, and heart. An MIMODS score >10 suggests an MID.
Collapse
|
20
|
Miyawaki T, Koto S, Ishihara H, Goto Y, Nishino I, Kanda F, Toda T. [A case of neurologic muscle weakness, ataxia, and retinitis pigmentosa (NARP) syndrome with a novel mitochondrial mutation m.8729 G>A]. Rinsho Shinkeigaku 2016; 55:91-5. [PMID: 25746071 DOI: 10.5692/clinicalneurol.55.91] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We report a patient having classical clinical feature of neurologic muscle weakness, ataxia, and retinitis pigmentosa (NARP) and a novel mutation, m.8729 G>A in mitochondria DNA. The patient was referred to our hospital because of progressive ataxia in her limbs and trunk. She had a history of incapability of running long distances from childhood. Neurological examination revealed cerebellar ataxia, distal dominant muscle weakness in the limbs, hyporeflexia, hypoesthesia, myoclonus, sensorineural deafness, and retinitis pigmentosa. Magnetic resonance imaging (MRI) showed atrophy of brain stem and cerebellum as well as calcification of basal ganglia. In both serum and cerebrospinal fluid, lactate and pyruvate levels were elevated. Histological examination of biopsied muscle revealed chronic neurogenic changes without ragged red fibers. Genetic analysis of mitochondrial DNA (mtDNA) of the muscle revealed a heteroplasmic mutation, m.8729 G>A. Chemical analysis of the respiratory chain complexes in her muscle specimen demonstrated lower activities of complexes I and V. In our case, novel mutation of m.8729 G>A in mtDNA was indicated as the cause of NARP syndrome.
Collapse
|
21
|
A novel mutation m.8561C>G in MT-ATP6/8 causing a mitochondrial syndrome with ataxia, peripheral neuropathy, diabetes mellitus, and hypergonadotropic hypogonadism. J Neurol 2016; 263:2188-2195. [PMID: 27502083 DOI: 10.1007/s00415-016-8249-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 07/27/2016] [Accepted: 07/28/2016] [Indexed: 01/03/2023]
Abstract
Defects in the respiratory chain or mitochondrial ATP synthase (complex V) result in mitochondrial dysfunction that is an important cause of inherited neurological disease. Two of the subunits of complex V are encoded by MT-ATP6 and MT-ATP8 in the mitochondrial genome. Pathogenic mutations in MT-ATP6 are associated with the Leigh syndrome, the syndrome of neuropathy, ataxia, and retinitis pigmentosa (NARP), as well as with non-classical phenotypes, while MT-ATP8 is less frequently mutated in patients with mitochondrial disease. We investigated two adult siblings presenting with features of cerebellar ataxia, peripheral neuropathy, diabetes mellitus, sensorineural hearing impairment, and hypergonadotropic hypogonadism. As the phenotype was suggestive of mitochondrial disease, mitochondrial DNA was sequenced and a novel heteroplasmic mutation m.8561C>G in the overlapping region of the MT-ATP6 and MT-ATP8 was found. The mutation changed amino acids in both subunits. Mutation heteroplasmy correlated with the disease phenotype in five family members. An additional assembly intermediate of complex V and increased amount of subcomplex F1 were observed in myoblasts of the two patients, but the total amount of complex V was unaffected. Furthermore, intracellular ATP concentration was lower in patient myoblasts indicating defective energy production. We suggest that the m.8561C>G mutation in MT-ATP6/8 is pathogenic, leads biochemically to impaired assembly and decreased ATP production of complex V, and results clinically in a phenotype with the core features of cerebellar ataxia, peripheral neuropathy, diabetes mellitus, and hypergonadotropic hypogonadism.
Collapse
|
22
|
Sallevelt SCEH, de Die-Smulders CEM, Hendrickx ATM, Hellebrekers DMEI, de Coo IFM, Alston CL, Knowles C, Taylor RW, McFarland R, Smeets HJM. De novo mtDNA point mutations are common and have a low recurrence risk. J Med Genet 2016; 54:73-83. [PMID: 27450679 PMCID: PMC5502310 DOI: 10.1136/jmedgenet-2016-103876] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 06/02/2016] [Accepted: 06/09/2016] [Indexed: 12/25/2022]
Abstract
Background Severe, disease-causing germline mitochondrial (mt)DNA mutations are maternally inherited or arise de novo. Strategies to prevent transmission are generally available, but depend on recurrence risks, ranging from high/unpredictable for many familial mtDNA point mutations to very low for sporadic, large-scale single mtDNA deletions. Comprehensive data are lacking for de novo mtDNA point mutations, often leading to misconceptions and incorrect counselling regarding recurrence risk and reproductive options. We aim to study the relevance and recurrence risk of apparently de novo mtDNA point mutations. Methods Systematic study of prenatal diagnosis (PND) and recurrence of mtDNA point mutations in families with de novo cases, including new and published data. ‘De novo’ based on the absence of the mutation in multiple (postmitotic) maternal tissues is preferred, but mutations absent in maternal blood only were also included. Results In our series of 105 index patients (33 children and 72 adults) with (likely) pathogenic mtDNA point mutations, the de novo frequency was 24.6%, the majority being paediatric. PND was performed in subsequent pregnancies of mothers of four de novo cases. A fifth mother opted for preimplantation genetic diagnosis because of a coexisting Mendelian genetic disorder. The mtDNA mutation was absent in all four prenatal samples and all 11 oocytes/embryos tested. A literature survey revealed 137 de novo cases, but PND was only performed for 9 (including 1 unpublished) mothers. In one, recurrence occurred in two subsequent pregnancies, presumably due to germline mosaicism. Conclusions De novo mtDNA point mutations are a common cause of mtDNA disease. Recurrence risk is low. This is relevant for genetic counselling, particularly for reproductive options. PND can be offered for reassurance.
Collapse
Affiliation(s)
- Suzanne C E H Sallevelt
- Department of Clinical Genetics, Maastricht University Medical Centre (MUMC), Maastricht, The Netherlands
| | - Christine E M de Die-Smulders
- Department of Clinical Genetics, Maastricht University Medical Centre (MUMC), Maastricht, The Netherlands.,Research School for Developmental Biology (GROW), Maastricht University, Maastricht, The Netherlands
| | - Alexandra T M Hendrickx
- Department of Clinical Genetics, Maastricht University Medical Centre (MUMC), Maastricht, The Netherlands
| | - Debby M E I Hellebrekers
- Department of Clinical Genetics, Maastricht University Medical Centre (MUMC), Maastricht, The Netherlands
| | - Irenaeus F M de Coo
- Department of Neurology, Erasmus MC-Sophia Children's Hospital Rotterdam, Rotterdam, The Netherlands
| | - Charlotte L Alston
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Charlotte Knowles
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Robert W Taylor
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Robert McFarland
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Hubert J M Smeets
- Department of Clinical Genetics, Maastricht University Medical Centre (MUMC), Maastricht, The Netherlands.,Research School for Developmental Biology (GROW), Maastricht University, Maastricht, The Netherlands.,Research School for Cardiovascular Diseases in Maastricht, CARIM, Maastricht University, Maastricht, The Netherlands
| |
Collapse
|
23
|
Alsemari A, Al-Hindi HN. Large-scale mitochondrial DNA deletion underlying familial multiple system atrophy of the cerebellar subtype. Clin Case Rep 2015; 4:111-7. [PMID: 26862402 PMCID: PMC4736521 DOI: 10.1002/ccr3.435] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Revised: 09/03/2015] [Accepted: 09/29/2015] [Indexed: 11/29/2022] Open
Abstract
A family with mitochondrial inheritance of multiple system atrophy of the cerebellar subtype. MRI brain shows significant cerebellar atrophy with mild pontine atrophy and the classical hot cross bun sign in Pons. The muscle biopsy was indicative of mitochondrial myopathy. Mitochondrial DNA analysis revealed a low‐level large mtDNA deletion, m.3264_1607del12806 bp.
Collapse
Affiliation(s)
- Abdulaziz Alsemari
- Department of Neurosciences King Faisal Specialist Hospital and Research Centre PO box 3354 Riyadh 11211 Saudi Arabia
| | - Hindi Nasser Al-Hindi
- Department of Pathology and Laboratory Medicine King Faisal Specialist Hospital and Research Centre PO box 3354 Riyadh 11211 Saudi Arabia
| |
Collapse
|
24
|
Komatsu M, Wheeler HE, Chung S, Low SK, Wing C, Delaney SM, Gorsic LK, Takahashi A, Kubo M, Kroetz DL, Zhang W, Nakamura Y, Dolan ME. Pharmacoethnicity in Paclitaxel-Induced Sensory Peripheral Neuropathy. Clin Cancer Res 2015; 21:4337-46. [PMID: 26015512 DOI: 10.1158/1078-0432.ccr-15-0133] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 05/20/2015] [Indexed: 12/22/2022]
Abstract
PURPOSE Paclitaxel is used worldwide in the treatment of breast, lung, ovarian, and other cancers. Sensory peripheral neuropathy is an associated adverse effect that cannot be predicted, prevented, or mitigated. To better understand the contribution of germline genetic variation to paclitaxel-induced peripheral neuropathy, we undertook an integrative approach that combines genome-wide association study (GWAS) data generated from HapMap lymphoblastoid cell lines (LCL) and Asian patients. METHODS GWAS was performed with paclitaxel-induced cytotoxicity generated in 363 LCLs and with paclitaxel-induced neuropathy from 145 Asian patients. A gene-based approach was used to identify overlapping genes and compare with a European clinical cohort of paclitaxel-induced neuropathy. Neurons derived from human-induced pluripotent stem cells were used for functional validation of candidate genes. RESULTS SNPs near AIPL1 were significantly associated with paclitaxel-induced cytotoxicity in Asian LCLs (P < 10(-6)). Decreased expression of AIPL1 resulted in decreased sensitivity of neurons to paclitaxel by inducing neurite morphologic changes as measured by increased relative total outgrowth, number of processes and mean process length. Using a gene-based analysis, there were 32 genes that overlapped between Asian LCL cytotoxicity and Asian patient neuropathy (P < 0.05), including BCR. Upon BCR knockdown, there was an increase in neuronal sensitivity to paclitaxel as measured by neurite morphologic characteristics. CONCLUSIONS We identified genetic variants associated with Asian paclitaxel-induced cytotoxicity and functionally validated the AIPL1 and BCR in a neuronal cell model. Furthermore, the integrative pharmacogenomics approach of LCL/patient GWAS may help prioritize target genes associated with chemotherapeutic-induced peripheral neuropathy.
Collapse
Affiliation(s)
- Masaaki Komatsu
- Section of Hematology/Oncology, Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Heather E Wheeler
- Section of Hematology/Oncology, Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Suyoun Chung
- Section of Hematology/Oncology, Department of Medicine, The University of Chicago, Chicago, Illinois. Division of Cancer Development System, National Cancer Center Research Institute, Tokyo, Japan
| | - Siew-Kee Low
- Laboratory for Statistical Analysis, Core for Genomic Medicine, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan. Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Claudia Wing
- Section of Hematology/Oncology, Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Shannon M Delaney
- Section of Hematology/Oncology, Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Lidija K Gorsic
- Section of Hematology/Oncology, Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Atsushi Takahashi
- Laboratory for Statistical Analysis, Core for Genomic Medicine, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Michiaki Kubo
- Laboratory for Genotyping Development, Core for Genomic Medicine, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Deanna L Kroetz
- Department of Bioengineering and Therapeutic Sciences, School of Pharmacy and Medicine, University of California, San Francisco, San Francisco, California
| | - Wei Zhang
- Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Yusuke Nakamura
- Section of Hematology/Oncology, Department of Medicine, The University of Chicago, Chicago, Illinois. Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - M Eileen Dolan
- Section of Hematology/Oncology, Department of Medicine, The University of Chicago, Chicago, Illinois.
| |
Collapse
|
25
|
Alteration of structure and function of ATP synthase and cytochrome c oxidase by lack of Fo-a and Cox3 subunits caused by mitochondrial DNA 9205delTA mutation. Biochem J 2015; 466:601-11. [PMID: 25588698 DOI: 10.1042/bj20141462] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Mutations in the MT-ATP6 gene are frequent causes of severe mitochondrial disorders. Typically, these are missense mutations, but another type is represented by the 9205delTA microdeletion, which removes the stop codon of the MT-ATP6 gene and affects the cleavage site in the MT-ATP8/MT-ATP6/MT-CO3 polycistronic transcript. This interferes with the processing of mRNAs for the Atp6 (Fo-a) subunit of ATP synthase and the Cox3 subunit of cytochrome c oxidase (COX). Two cases described so far presented with strikingly different clinical phenotypes-mild transient lactic acidosis or fatal encephalopathy. To gain more insight into the pathogenic mechanism, we prepared 9205delTA cybrids with mutation load ranging between 52 and 99% and investigated changes in the structure and function of ATP synthase and the COX. We found that 9205delTA mutation strongly reduces the levels of both Fo-a and Cox3 proteins. Lack of Fo-a alters the structure but not the content of ATP synthase, which assembles into a labile, ∼60 kDa smaller, complex retaining ATP hydrolytic activity but which is unable to synthesize ATP. In contrast, lack of Cox3 limits the biosynthesis of COX but does not alter the structure of the enzyme. Consequently, the diminished mitochondrial content of COX and non-functional ATP synthase prevent most mitochondrial ATP production. The biochemical effects caused by the 9205delTA microdeletion displayed a pronounced threshold effect above ∼90% mutation heteroplasmy. We observed a linear relationship between the decrease in subunit Fo-a or Cox3 content and the functional presentation of the defect. Therefore we conclude that the threshold effect originated from a gene-protein level.
Collapse
|
26
|
Recent advances of stem cell therapy for retinitis pigmentosa. Int J Mol Sci 2014; 15:14456-74. [PMID: 25141102 PMCID: PMC4159862 DOI: 10.3390/ijms150814456] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 07/24/2014] [Accepted: 08/11/2014] [Indexed: 12/22/2022] Open
Abstract
Retinitis pigmentosa (RP) is a group of inherited retinal disorders characterized by progressive loss of photoreceptors and eventually leads to retina degeneration and atrophy. Until now, the exact pathogenesis and etiology of this disease has not been clear, and many approaches for RP therapies have been carried out in animals and in clinical trials. In recent years, stem cell transplantation-based attempts made some progress, especially the transplantation of bone marrow-derived mesenchymal stem cells (BMSCs). This review will provide an overview of stem cell-based treatment of RP and its main problems, to provide evidence for the safety and feasibility for further clinical treatment.
Collapse
|
27
|
López-Gallardo E, Emperador S, Solano A, Llobet L, Martín-Navarro A, López-Pérez MJ, Briones P, Pineda M, Artuch R, Barraquer E, Jericó I, Ruiz-Pesini E, Montoya J. Expanding the clinical phenotypes of MT-ATP6 mutations. Hum Mol Genet 2014; 23:6191-200. [DOI: 10.1093/hmg/ddu339] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
|
28
|
Anasagasti A, Barandika O, Irigoyen C, Benitez BA, Cooper B, Cruchaga C, López de Munain A, Ruiz-Ederra J. Genetic high throughput screening in Retinitis Pigmentosa based on high resolution melting (HRM) analysis. Exp Eye Res 2014; 116:386-394. [PMID: 24416769 DOI: 10.1016/j.exer.2013.10.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Retinitis Pigmentosa (RP) involves a group of genetically determined retinal diseases caused by a large number of mutations that result in rod photoreceptor cell death followed by gradual death of cone cells. Most cases of RP are monogenic, with more than 80 associated genes identified so far. The high number of genes and variants involved in RP, among other factors, is making the molecular characterization of RP a real challenge for many patients. Although HRM has been used for the analysis of isolated variants or single RP genes, as far as we are concerned, this is the first study that uses HRM analysis for a high-throughput screening of several RP genes. Our main goal was to test the suitability of HRM analysis as a genetic screening technique in RP, and to compare its performance with two of the most widely used NGS platforms, Illumina and PGM-Ion Torrent technologies. RP patients (n = 96) were clinically diagnosed at the Ophthalmology Department of Donostia University Hospital, Spain. We analyzed a total of 16 RP genes that meet the following inclusion criteria: 1) size: genes with transcripts of less than 4 kb; 2) number of exons: genes with up to 22 exons; and 3) prevalence: genes reported to account for, at least, 0.4% of total RP cases worldwide. For comparison purposes, RHO gene was also sequenced with Illumina (GAII; Illumina), Ion semiconductor technologies (PGM; Life Technologies) and Sanger sequencing (ABI 3130xl platform; Applied Biosystems). Detected variants were confirmed in all cases by Sanger sequencing and tested for co-segregation in the family of affected probands. We identified a total of 65 genetic variants, 15 of which (23%) were novel, in 49 out of 96 patients. Among them, 14 (4 novel) are probable disease-causing genetic variants in 7 RP genes, affecting 15 patients. Our HRM analysis-based study, proved to be a cost-effective and rapid method that provides an accurate identification of genetic RP variants. This approach is effective for medium sized (<4 kb transcript) RP genes, which constitute over 80% of the total of known RP genes.
Collapse
Affiliation(s)
- Ander Anasagasti
- Department of Neuroscience, Instituto Biodonostia, Paseo Dr. Begiristain s/n, E-20014 San Sebastián, Spain
| | - Olatz Barandika
- Department of Neuroscience, Instituto Biodonostia, Paseo Dr. Begiristain s/n, E-20014 San Sebastián, Spain
| | - Cristina Irigoyen
- Department of Ophthalmology, Hospital Universitario Donostia, San Sebastián, Spain
| | - Bruno A Benitez
- Department of Psychiatry, Washington University, St. Louis, MO, USA
| | - Breanna Cooper
- Department of Psychiatry, Washington University, St. Louis, MO, USA
| | - Carlos Cruchaga
- Department of Psychiatry, Washington University, St. Louis, MO, USA; Hope Center Program on Protein Aggregation and Neurodegeneration, Washington University, St. Louis, MO, USA
| | - Adolfo López de Munain
- Department of Neuroscience, Instituto Biodonostia, Paseo Dr. Begiristain s/n, E-20014 San Sebastián, Spain; Department of Neurology, Hospital Universitario Donostia, San Sebastián, Spain; CIBERNED, Centro de Investigaciones Biomédicas en Red sobre Enfermedades Neurodegenerativas, Instituto Carlos III, Ministerio de Economía y Competitividad, Spain; Department of Neurosciences, University of the Basque Country UPV-EHU, Spain; Euskampus, University of the Basque Country UPV-EHU, Spain
| | - Javier Ruiz-Ederra
- Department of Neuroscience, Instituto Biodonostia, Paseo Dr. Begiristain s/n, E-20014 San Sebastián, Spain.
| |
Collapse
|
29
|
Horan MP, Cooper DN. The emergence of the mitochondrial genome as a partial regulator of nuclear function is providing new insights into the genetic mechanisms underlying age-related complex disease. Hum Genet 2013; 133:435-58. [DOI: 10.1007/s00439-013-1402-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 11/23/2013] [Indexed: 12/17/2022]
|
30
|
Kabala AM, Lasserre JP, Ackerman SH, di Rago JP, Kucharczyk R. Defining the impact on yeast ATP synthase of two pathogenic human mitochondrial DNA mutations, T9185C and T9191C. Biochimie 2013; 100:200-6. [PMID: 24316278 DOI: 10.1016/j.biochi.2013.11.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 11/25/2013] [Indexed: 12/18/2022]
Abstract
Mutations in the human mitochondrial ATP6 gene encoding ATP synthase subunit a/6 (referred to as Atp6p in yeast) are at the base of neurodegenerative disorders like Neurogenic Ataxia and Retinitis Pigmentosa (NARP), Leigh syndrome (LS), Charcot-Marie-Tooth (CMT), and ataxia telangiectasia. In previous studies, using the yeast Saccharomyces cerevisiae as a model we were able to better define how several of these mutations impact the ATP synthase. Here we report the construction of yeast models of two other ATP6 pathogenic mutations, T9185C and T9191C. The first one was reported as conferring a mild, sometimes reversible, CMT clinical phenotype; the second one has been described in a patient presenting with severe LS. We found that an equivalent of the T9185C mutation partially impaired the functioning of yeast ATP synthase, with only a 30% deficit in mitochondrial ATP production. An equivalent of the mutation T9191C had much more severe effects, with a nearly complete block in yeast Atp6p assembly and an >95% drop in the rate of ATP synthesis. These findings provide a molecular basis for the relative severities of the diseases induced by T9185C and T9191C.
Collapse
Affiliation(s)
- Anna Magdalena Kabala
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland; Institut de Biochimie et Génétique Cellulaires, CNRS UMR5095, Université Bordeaux Segalen, 1 Rue Camille Saint-Saëns, Bordeaux 33077 cedex, France
| | - Jean-Paul Lasserre
- Institut de Biochimie et Génétique Cellulaires, CNRS UMR5095, Université Bordeaux Segalen, 1 Rue Camille Saint-Saëns, Bordeaux 33077 cedex, France
| | - Sharon H Ackerman
- Department of Biochemistry and Molecular Biology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Jean-Paul di Rago
- Institut de Biochimie et Génétique Cellulaires, CNRS UMR5095, Université Bordeaux Segalen, 1 Rue Camille Saint-Saëns, Bordeaux 33077 cedex, France
| | - Roza Kucharczyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
| |
Collapse
|
31
|
Pinto M, Moraes CT. Mitochondrial genome changes and neurodegenerative diseases. Biochim Biophys Acta Mol Basis Dis 2013; 1842:1198-207. [PMID: 24252612 DOI: 10.1016/j.bbadis.2013.11.012] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 11/06/2013] [Accepted: 11/08/2013] [Indexed: 12/12/2022]
Abstract
Mitochondria are essential organelles within the cell where most of the energy production occurs by the oxidative phosphorylation system (OXPHOS). Critical components of the OXPHOS are encoded by the mitochondrial DNA (mtDNA) and therefore, mutations involving this genome can be deleterious to the cell. Post-mitotic tissues, such as muscle and brain, are most sensitive to mtDNA changes, due to their high energy requirements and non-proliferative status. It has been proposed that mtDNA biological features and location make it vulnerable to mutations, which accumulate over time. However, although the role of mtDNA damage has been conclusively connected to neuronal impairment in mitochondrial diseases, its role in age-related neurodegenerative diseases remains speculative. Here we review the pathophysiology of mtDNA mutations leading to neurodegeneration and discuss the insights obtained by studying mouse models of mtDNA dysfunction.
Collapse
Affiliation(s)
- Milena Pinto
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Carlos T Moraes
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Neuroscience Graduate Program, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
| |
Collapse
|
32
|
Mitochondrial disorders: aetiologies, models systems, and candidate therapies. Trends Genet 2013; 29:488-97. [PMID: 23756086 DOI: 10.1016/j.tig.2013.05.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 05/01/2013] [Accepted: 05/03/2013] [Indexed: 01/14/2023]
Abstract
It has become evident that many human disorders are characterised by mitochondrial dysfunction either at a primary level, due to mutations in genes whose encoded products are involved in oxidative phosphorylation, or at a secondary level, due to the accumulation of mitochondrial DNA (mtDNA) mutations. This has prompted keen interest in the development of cell and animal models and in exploring innovative therapeutic strategies to modulate the mitochondrial deficiencies observed in these diseases. Key advances in these areas are outlined in this review, with a focus on Leber hereditary optic neuropathy (LHON). This exciting field is set to grow exponentially and yield many candidate therapies to treat this class of disease.
Collapse
|