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Borisova TV, Cherdonova AM, Pshennikova VG, Teryutin FM, Morozov IV, Bondar AA, Baturina OA, Kabilov MR, Romanov GP, Solovyev AV, Fedorova SA, Barashkov NA. High prevalence of m.1555A > G in patients with hearing loss in the Baikal Lake region of Russia as a result of founder effect. Sci Rep 2024; 14:15342. [PMID: 38961196 PMCID: PMC11222474 DOI: 10.1038/s41598-024-66254-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Accepted: 07/01/2024] [Indexed: 07/05/2024] Open
Abstract
Mitochondrial forms account approximately 1-2% of all nonsyndromic cases of hearing loss (HL). One of the most common causative variants of mtDNA is the m.1555A > G variant of the MT-RNR1 gene (OMIM 561000). Currently the detection of the m.1555A > G variant of the MT-RNR1 gene is not included in all research protocols. In this study this variant was screened among 165 patients with HL from the Republic of Buryatia, located in the Baikal Lake region of Russia. In our study, the total contribution of the m.1555A > G variant to the etiology of HL was 12.7% (21/165), while the update global prevalence of this variant is 1.8% (863/47,328). The m.1555A > G variant was notably more prevalent in Buryat (20.2%) than in Russian patients (1.3%). Mitogenome analysis in 14 unrelated Buryat families carrying the m.1555A > G variant revealed a predominant lineage: in 13 families, a cluster affiliated with sub-haplogroup A5b (92.9%) was identified, while one family had the D5a2a1 lineage (7.1%). In a Russian family with the m.1555A > G variant the lineage affiliated with sub-haplogroup F1a1d was found. Considering that more than 90% of Buryat families with the m.1555A > G variant belong to the single maternal lineage cluster we conclude that high prevalence of this variant in patients with HL in the Baikal Lake region can be attributed to a founder effect.
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Affiliation(s)
- Tuyara V Borisova
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
| | - Aleksandra M Cherdonova
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
| | - Vera G Pshennikova
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
- Laboratory of Molecular Genetics, Yakut Science Centre of Complex Medical Problems, Yaroslavskogo 6/3, 677000, Yakutsk, Russia
| | - Fedor M Teryutin
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
- Laboratory of Molecular Genetics, Yakut Science Centre of Complex Medical Problems, Yaroslavskogo 6/3, 677000, Yakutsk, Russia
| | - Igor V Morozov
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Akademika Lavrentieva 8, 630090, Novosibirsk, Russia
- Novosibirsk State University, 630090, Novosibirsk, Russia
| | - Alexander A Bondar
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Akademika Lavrentieva 8, 630090, Novosibirsk, Russia
| | - Olga A Baturina
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Akademika Lavrentieva 8, 630090, Novosibirsk, Russia
| | - Marsel R Kabilov
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Prospekt Akademika Lavrentieva 8, 630090, Novosibirsk, Russia
| | - Georgii P Romanov
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
| | - Aisen V Solovyev
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
| | - Sardana A Fedorova
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia
- Laboratory of Molecular Genetics, Yakut Science Centre of Complex Medical Problems, Yaroslavskogo 6/3, 677000, Yakutsk, Russia
| | - Nikolay A Barashkov
- Laboratory of Molecular Biology, Institute of Natural Sciences, M.K. Ammosov North-Eastern Federal University, Kulakovskogo 46, 677013, Yakutsk, Russia.
- Laboratory of Molecular Genetics, Yakut Science Centre of Complex Medical Problems, Yaroslavskogo 6/3, 677000, Yakutsk, Russia.
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Pavlidis P, Tseriotis VS, Papadopoulou K, Karachrysafi S, Sardeli C, Gouveris H, Malliou F, Kavvadas D, Papamitsou T, Sioga A, Anastasiadou P, Kouvelas D. Role of Memantine in Limiting Cochleotoxicity in Rats. Indian J Otolaryngol Head Neck Surg 2024; 76:2464-2473. [PMID: 38883494 PMCID: PMC11169147 DOI: 10.1007/s12070-024-04521-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 01/08/2024] [Indexed: 06/18/2024] Open
Abstract
Οur aim was to test whether amikacin's well-known cochleotoxic effects could be suppressed, depending on whether an NMDA-antagonist (memantine) was administered simultaneously with or after amikacin treatment. Forty Wistar rats were used in this experiment. Ten rats acted as controls and received no medication (group A). Amikacin (200 mg/kg) was administered intraperitoneally (i.p.) once daily for 14 days to 10 animals in group B; amikacin (200 mg/kg) was administered concurrently with memantine (10 mg/kg, i.p., once daily) to the same 10 animals in group C. Group D was given intraperitoneal memantine (10 mg/kg, once daily) for 14 days following a 2-week amikacin treatment. The cochlear activity of the right ear was tested using DPOAE in conscious animals. All animals were sacrificed at the conclusion of the experiment and both cochleae were collected for histological and immunohistochemical analysis. All groups treated with amikacin showed decreased cochlear activity, as testified by decreased DPOAE-amplitudes compared to the pre-treatment state. In the rats of group B, the DPOAE reduction was more pronounced. On histologic exam, the cochlear structures of group C rats and, although to a lesser extent, group D rats showed less severe cochlea damage. Memantine plays a protective role, resulting in restoring partially cochlear structures when administered either simultaneously with or after completion of amikacin i.p. treatment in rats.
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Affiliation(s)
- Pavlos Pavlidis
- Department of Otorhinolarhingology / Head & Neck Surgery, University Medical Center Mainz, Mainz, Germany
- Laboratory for Clinical Pharmacology, School of Medicine, Faculty of Health Sciences, Aristotle University Thessaloniki, Thessaloniki, Greece
| | - Vasilis Spyridon Tseriotis
- Laboratory for Clinical Pharmacology, School of Medicine, Faculty of Health Sciences, Aristotle University Thessaloniki, Thessaloniki, Greece
| | - Kyriaki Papadopoulou
- Laboratory of Histology-Embryology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Sophia Karachrysafi
- Laboratory of Histology-Embryology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Chrysanthi Sardeli
- Laboratory for Clinical Pharmacology, School of Medicine, Faculty of Health Sciences, Aristotle University Thessaloniki, Thessaloniki, Greece
| | - Haralampos Gouveris
- Department of Otorhinolarhingology / Head & Neck Surgery, University Medical Center Mainz, Mainz, Germany
| | - Faye Malliou
- Laboratory for Clinical Pharmacology, School of Medicine, Faculty of Health Sciences, Aristotle University Thessaloniki, Thessaloniki, Greece
| | - Dimitrios Kavvadas
- Laboratory of Histology-Embryology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Theodora Papamitsou
- Laboratory of Histology-Embryology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Antonia Sioga
- Laboratory of Histology-Embryology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Penelope Anastasiadou
- Department of Oral Medicine/Pathology, School of Dentistry, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Dimitrios Kouvelas
- Laboratory for Clinical Pharmacology, School of Medicine, Faculty of Health Sciences, Aristotle University Thessaloniki, Thessaloniki, Greece
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Diab KMA, Meshcheryakov KL, Sokolova VN, Plyakina AA, Mamedov VE. [Pediatric sensorineural hearing loss related COVID-19. Clinical cases]. Vestn Otorinolaringol 2024; 89:64-68. [PMID: 39104275 DOI: 10.17116/otorino20248903164] [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] [Indexed: 08/07/2024]
Abstract
COVID-19 is an acute respiratory coronavirus infection in 2019 caused by the SARS-CoV-2 virus. Currently, the number of neurological complications in the acute or delayed period of coronavirus disease is increasing, including peripheral disorders of the auditory analyzer. OBJECTIVE To present clinical cases of sensorineural hearing loss in children under 5 years of age after a novel coronavirus infection. MATERIAL AND METHODS We report 3 cases of unilateral and 1 case of bilateral acquired deep sensorineural hearing loss, while the association with SARS-CoV-2 has been confirmed anamnetically and/or laboratory. RESULTS The SARS-CoV-2 virus can have a depressing effect on the cochlea on its own or enhance the toxic effect of viruses during the recovery period after COVID-19. The true frequency of acute sensorineural hearing loss of infectious origin in childhood and, as its outcome, the formation of persistent hearing impairment has not been determined. CONCLUSION Viruses are volatile, contagious, and clinically dangerous due to their complications. Vaccination is the most effective measure for the prevention of infectious diseases.
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Affiliation(s)
- Kh M-A Diab
- National Medical Research Center for Children's Health, Moscow, Russia
- National Medical Research Center for Otorhinolaryngology, Moscow, Russia
| | - K L Meshcheryakov
- National Medical Research Center for Children's Health, Moscow, Russia
| | - V N Sokolova
- National Medical Research Center for Children's Health, Moscow, Russia
| | - A A Plyakina
- National Medical Research Center for Children's Health, Moscow, Russia
| | - V E Mamedov
- National Medical Research Center for Children's Health, Moscow, Russia
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Jerome MS, Nanjappa DP, Chakraborty A, Chakrabarty S. Molecular etiology of defective nuclear and mitochondrial ribosome biogenesis: Clinical phenotypes and therapy. Biochimie 2023; 207:122-136. [PMID: 36336106 DOI: 10.1016/j.biochi.2022.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 10/27/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022]
Abstract
Ribosomopathies are rare congenital disorders associated with defective ribosome biogenesis due to pathogenic variations in genes that encode proteins related to ribosome function and biogenesis. Defects in ribosome biogenesis result in a nucleolar stress response involving the TP53 tumor suppressor protein and impaired protein synthesis leading to a deregulated translational output. Despite the accepted notion that ribosomes are omnipresent and essential for all cells, most ribosomopathies show tissue-specific phenotypes affecting blood cells, hair, spleen, or skin. On the other hand, defects in mitochondrial ribosome biogenesis are associated with a range of clinical manifestations affecting more than one organ. Intriguingly, the deregulated ribosomal function is also a feature in several human malignancies with a selective upregulation or downregulation of specific ribosome components. Here, we highlight the clinical conditions associated with defective ribosome biogenesis in the nucleus and mitochondria with a description of the affected genes and the implicated pathways, along with a note on the treatment strategies currently available for these disorders.
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Affiliation(s)
- Maria Sona Jerome
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| | - Dechamma Pandyanda Nanjappa
- Division of Molecular Genetics and Cancer, Nitte University Centre for Science Education and Research (NUCSER), NITTE (Deemed to Be University), Deralakate, Mangaluru, 575018, India
| | - Anirban Chakraborty
- Division of Molecular Genetics and Cancer, Nitte University Centre for Science Education and Research (NUCSER), NITTE (Deemed to Be University), Deralakate, Mangaluru, 575018, India.
| | - Sanjiban Chakrabarty
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India.
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[Hereditary hearing loss]. HNO 2023; 71:131-142. [PMID: 36526931 DOI: 10.1007/s00106-022-01254-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2022] [Indexed: 12/23/2022]
Abstract
Understanding the genetic basis of hearing loss is becoming increasingly relevant, as 50-70% of congenital hearing loss is hereditary and postlingual hearing loss is also often of hereditary origin. To date, more than 220 genes for hearing loss have been identified and more than 600 syndromes with hearing loss described. This review article explains the classification of genetic hearing loss into syndromic versus non-syndromic forms and the modes of inheritance involved. Some of the most common syndromes (Usher, Pendred, Jervell-Lange-Nielsen, Waardenburg, branchiootorenal, and Alport syndrome) are introductorily described. New sequencing technologies have significantly expanded the diagnostic options for genetic hearing loss and made them more accessible. This text aims to encourage initiation of genetic diagnosis in hearing-impaired patients with suspected hereditary genesis in order to provide the best possible counseling for affected individuals and their families.
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Yonova-Doing E, Calabrese C, Gomez-Duran A, Schon K, Wei W, Karthikeyan S, Chinnery PF, Howson JMM. An atlas of mitochondrial DNA genotype-phenotype associations in the UK Biobank. Nat Genet 2021; 53:982-993. [PMID: 34002094 PMCID: PMC7611844 DOI: 10.1038/s41588-021-00868-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 04/07/2021] [Indexed: 02/03/2023]
Abstract
Mitochondrial DNA (mtDNA) variation in common diseases has been underexplored, partly due to a lack of genotype calling and quality-control procedures. Developing an at-scale workflow for mtDNA variant analyses, we show correlations between nuclear and mitochondrial genomic structures within subpopulations of Great Britain and establish a UK Biobank reference atlas of mtDNA-phenotype associations. A total of 260 mtDNA-phenotype associations were new (P < 1 × 10-5), including rs2853822 /m.8655 C>T (MT-ATP6) with type 2 diabetes, rs878966690 /m.13117 A>G (MT-ND5) with multiple sclerosis, 6 mtDNA associations with adult height, 24 mtDNA associations with 2 liver biomarkers and 16 mtDNA associations with parameters of renal function. Rare-variant gene-based tests implicated complex I genes modulating mean corpuscular volume and mean corpuscular hemoglobin. Seven traits had both rare and common mtDNA associations, where rare variants tended to have larger effects than common variants. Our work illustrates the value of studying mtDNA variants in common complex diseases and lays foundations for future large-scale mtDNA association studies.
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Affiliation(s)
- Ekaterina Yonova-Doing
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- Department of Genetics, Novo Nordisk Research Centre Oxford, Oxford, UK
| | - Claudia Calabrese
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Aurora Gomez-Duran
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
- Centro de Investigaciones Biológicas "Margarita Salas", Consejo Superior de Investigaciones Científicas (CIB-CSIC), Madrid, Spain
| | - Katherine Schon
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Wei Wei
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Savita Karthikeyan
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Patrick F Chinnery
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK.
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK.
| | - Joanna M M Howson
- British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
- Department of Genetics, Novo Nordisk Research Centre Oxford, Oxford, UK.
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Fu X, Wan P, Li P, Wang J, Guo S, Zhang Y, An Y, Ye C, Liu Z, Gao J, Yang J, Fan J, Chai R. Mechanism and Prevention of Ototoxicity Induced by Aminoglycosides. Front Cell Neurosci 2021; 15:692762. [PMID: 34211374 PMCID: PMC8239227 DOI: 10.3389/fncel.2021.692762] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 05/20/2021] [Indexed: 02/02/2023] Open
Abstract
Aminoglycosides, a class of clinically important drugs, are widely used worldwide against gram-negative bacterial infections. However, there is growing evidence that aminoglycosides can cause hearing loss or balance problems. In this article, we mainly introduce the main mechanism of ototoxicity induced by aminoglycosides. Genetic analysis showed that the susceptibility of aminoglycosides was attributable to mutations in mtDNA, especially A1555G and C1494T mutations in 12S rRNA. In addition, the overexpression of NMDA receptors and the formation of free radicals also play an important role. Understanding the mechanism of ototoxicity induced by aminoglycosides is helpful to develop new therapeutic methods to protect hearing. In this article, the prevention methods of ototoxicity induced by aminoglycosides were introduced from the upstream and downstream aspects.
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Affiliation(s)
- Xiaolong Fu
- State Key Laboratory of Bioelectronics, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, School of Life Sciences and Technology, Southeast University, Nanjing, China
| | - Peifeng Wan
- School of Life Science, Shandong University, Qingdao, China
| | - Peipei Li
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jinpeng Wang
- The Key Laboratory of Animal Resistant Biology of Shandong, College of Life Science, Shandong Normal University, Jinan, China
| | - Siwei Guo
- School of Life Science, Shandong University, Qingdao, China
| | - Yuan Zhang
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yachun An
- School of Life Science, Shandong University, Qingdao, China
| | - Chao Ye
- School of Life Science, Shandong University, Qingdao, China
| | - Ziyi Liu
- School of Life Science, Shandong University, Qingdao, China
| | - Jiangang Gao
- School of Life Science, Shandong University, Qingdao, China
| | - Jianming Yang
- Second Hospital of Anhui Medical University, Hefei, China
| | - Jiangang Fan
- Department of Otolaryngology Head and Neck Surgery, Sichuan Academy of Medical Science, Sichuan Provincial People's Hospital, Chengdu, China
| | - Renjie Chai
- State Key Laboratory of Bioelectronics, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, School of Life Sciences and Technology, Southeast University, Nanjing, China.,Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China.,Institute of Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China.,Beijing Key Laboratory of Neural Regeneration and Repair, Capital Medical University, Beijing, China
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Maeda Y, Sasaki A, Kasai S, Goto S, Nishio SY, Sawada K, Tokuda I, Itoh K, Usami SI, Matsubara A. Prevalence of the mitochondrial 1555 A>G and 1494 C>T mutations in a community-dwelling population in Japan. Hum Genome Var 2020; 7:27. [PMID: 33014404 PMCID: PMC7501278 DOI: 10.1038/s41439-020-00115-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 08/07/2020] [Accepted: 08/13/2020] [Indexed: 02/04/2023] Open
Abstract
Single nucleotide polymorphisms in mitochondrial DNA, such as mitochondrial 1555 A>G (m.1555 A>G) and mitochondrial 1494 C>T (m.1494 C>T), are known to be causative mutations of nonsyndromic hearing loss following exposure to aminoglycoside antibiotics. The prevalence of the m.1555 A>G and m.1494 C>T mutations has not been reported for the general population in Japan. The purpose of this study was to investigate the prevalence of m.1555 A>G and m.1494 C>T mutations in a community-dwelling population in Japan in order to prevent aminoglycoside-induced hearing loss. We recruited participants older than 20 years of age to the Iwaki Health Promotion Project in 2014, 2015, and 2016, resulting in the recruitment of 1,683 participants. For each participant, we performed a hearing test and a genetic test for the m.1555 A>G and m.1494 C>T mutations using the TaqMan genotyping method. The m.1555 A>G mutation was detected in only 1 of the 1,683 participants (0.06%). This carrier of the m.1555 A>G mutation was a 69-year-old male with bilateral, symmetric, and high-frequency hearing loss. We provided genetic counseling and distributed a drug card advising him to avoid the administration of aminoglycoside antibiotics. In contrast, the m.1494 C>T mutation was not detected in this study population.
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Affiliation(s)
- Yasunori Maeda
- Department of Otorhinolaryngology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Akira Sasaki
- Department of Otorhinolaryngology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shuya Kasai
- Department of Stress Response Science, Center for Advanced Medical Research, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shinichi Goto
- Department of Otorhinolaryngology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shin-ya Nishio
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Kaori Sawada
- Department of Social Medicine, Hirosaki University School of Medicine, Hirosaki, Japan
| | - Itoyo Tokuda
- Department of Social Medicine, Hirosaki University School of Medicine, Hirosaki, Japan
| | - Ken Itoh
- Department of Stress Response Science, Center for Advanced Medical Research, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shin-ichi Usami
- Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan
- Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Atsushi Matsubara
- Department of Otorhinolaryngology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
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Igumnova V, Veidemane L, Vīksna A, Capligina V, Zole E, Ranka R. The prevalence of mitochondrial mutations associated with aminoglycoside-induced deafness in ethnic Latvian population: the appraisal of the evidence. J Hum Genet 2018; 64:199-206. [PMID: 30523288 DOI: 10.1038/s10038-018-0544-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 11/02/2018] [Accepted: 11/02/2018] [Indexed: 11/09/2022]
Abstract
Aminoglycosides are potent antibiotics which are used to treat severe gram-negative infections, neonatal sepsis, and multidrug-resistant tuberculosis. Ototoxicity is a well-known side effect of aminoglycosides, and a rapid, profound, and irreversible hearing loss can occur in predisposed individuals. MT-RNR1 gene encoding the mitochondrial ribosomal 12S subunit is a hot spot for aminoglycoside-induced hearing loss mutations, however, a variability in the nature and frequency of genetic changes in different populations exists. The objective of this study was to analyze MT-RNR1 gene mutations in a Baltic-speaking Latvian population, and to estimate the prevalence of such genetic changes in the population-specific mitochondrial haplogroups. In the cohort of 191 ethnic non-related Latvians, the presence of two deafness-associated mutations, m.1555A>G and m.827A>G, three potentially pathogenic variations, m.961insC(n), m.961T>G and m.951G>A, and one unknown substitution, m961T>A was detected, and the aggregate frequency of all variants was 7.3%. All genetic changes were detected in samples belonged to the haplogroups H, U, T, and J. The presence of several aminoglycoside ototoxicity-related MT-RNR1 gene mutations in Baltic-speaking Latvian population indicates the necessity to include ototoxicity-related mutation analysis in the future studies in order to determine the feasibility of DNA screening for patients before administration of aminoglycoside therapy.
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Affiliation(s)
- Viktorija Igumnova
- Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga, LV-1067, Latvia.,Department of Pharmaceutical Chemistry, Rīga Stradinš University, Dzirciema Str. 16, Riga, LV-1007, Latvia
| | - Lauma Veidemane
- Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga, LV-1067, Latvia
| | - Anda Vīksna
- Centre of Tuberculosis and Lung Diseases, Riga East University Hospital, Stopiņi region, Upeslejas, LV-2118, Latvia
| | - Valentina Capligina
- Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga, LV-1067, Latvia
| | - Egija Zole
- Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga, LV-1067, Latvia
| | - Renate Ranka
- Latvian Biomedical Research and Study Centre, Ratsupites Str. 1, Riga, LV-1067, Latvia. .,Department of Pharmaceutical Chemistry, Rīga Stradinš University, Dzirciema Str. 16, Riga, LV-1007, Latvia.
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10
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Moassass F, Al-Halabi B, Nweder MS, Al-Achkar W. Investigation of the mtDNA mutations in Syrian families with non-syndromic sensorineural hearing loss. Int J Pediatr Otorhinolaryngol 2018; 113:110-114. [PMID: 30173967 DOI: 10.1016/j.ijporl.2018.07.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 07/16/2018] [Accepted: 07/17/2018] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Hearing loss is a common sensory disorder, and at least 50% of cases are due to a genetic etiology. Several mitochondrial DNA mutations (mtDNA) have been reported to be associated with nonsyndromic hearing loss (NSHL) in different population. However, There is no previous available data about the frequency of mtDNA mutations as etiology for deafness in Syrian. The aim of present study is to investigate the incidence of common mt DNA mutations in our families with congenital hearing loss and not related to the ototoxicity or aminoglycosides. METHODS A total of 50 deaf families were enrolled in the present study. Direct sequencing and PCR-RFLP methods were employed to detect seven mt DNA mutations, including A1555G, A3243G, C1494T, G3316A, T7510C, A7445G, and 7472insC. RESULTS Our results revealed a high prevalence of mt DNA mutation (10%) in deaf families (5/50). In surprising, the unexpected mutations were observed. The G3316A mutation was found in 2 families as homoplasmic genotype. Also, we found the homoplasmic and heteroplasmic genotype for the C1494T mutation in two families. In one family the heteroplasmic genotype for T7510C mutation was observed; this family harbor 35delG mutation in GJB2 gene. None of the common mtDNA mutations (A1555G, A3243G) and other mutations (A7445G, 7472insC) were detected here. CONCLUSION Our findings indicate to significant contribution of the mt DNA mutations in our families with NSHL. The presented data is the first report about mt DNA and it will improve the genetic counseling of hearing impaired in Syrian families.
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Affiliation(s)
- Faten Moassass
- Human Genetics Division, Molecular Biology and Biotechnology Department, Atomic Energy Commission, Damascus, Syria
| | - Bassel Al-Halabi
- Human Genetics Division, Molecular Biology and Biotechnology Department, Atomic Energy Commission, Damascus, Syria
| | - Mohamad Sayah Nweder
- Human Genetics Division, Molecular Biology and Biotechnology Department, Atomic Energy Commission, Damascus, Syria
| | - Walid Al-Achkar
- Human Genetics Division, Molecular Biology and Biotechnology Department, Atomic Energy Commission, Damascus, Syria.
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Akbergenov R, Duscha S, Fritz AK, Juskeviciene R, Oishi N, Schmitt K, Shcherbakov D, Teo Y, Boukari H, Freihofer P, Isnard-Petit P, Oettinghaus B, Frank S, Thiam K, Rehrauer H, Westhof E, Schacht J, Eckert A, Wolfer D, Böttger EC. Mutant MRPS5 affects mitoribosomal accuracy and confers stress-related behavioral alterations. EMBO Rep 2018; 19:embr.201846193. [PMID: 30237157 PMCID: PMC6216279 DOI: 10.15252/embr.201846193] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 08/21/2018] [Accepted: 08/24/2018] [Indexed: 12/30/2022] Open
Abstract
The 1555 A to G substitution in mitochondrial 12S A‐site rRNA is associated with maternally transmitted deafness of variable penetrance in the absence of otherwise overt disease. Here, we recapitulate the suggested A1555G‐mediated pathomechanism in an experimental model of mitoribosomal mistranslation by directed mutagenesis of mitoribosomal protein MRPS5. We first establish that the ratio of cysteine/methionine incorporation and read‐through of mtDNA‐encoded MT‐CO1 protein constitute reliable measures of mitoribosomal misreading. Next, we demonstrate that human HEK293 cells expressing mutant V336Y MRPS5 show increased mitoribosomal mistranslation. As for immortalized lymphocytes of individuals with the pathogenic A1555G mutation, we find little changes in the transcriptome of mutant V336Y MRPS5 HEK cells, except for a coordinated upregulation of transcripts for cytoplasmic ribosomal proteins. Homozygous knock‐in mutant Mrps5 V338Y mice show impaired mitochondrial function and a phenotype composed of enhanced susceptibility to noise‐induced hearing damage and anxiety‐related behavioral alterations. The experimental data in V338Y mutant mice point to a key role of mitochondrial translation and function in stress‐related behavioral and physiological adaptations.
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Affiliation(s)
- Rashid Akbergenov
- Institut für Medizinische Mikrobiologie, Universität Zürich, Zürich, Switzerland
| | - Stefan Duscha
- Institut für Medizinische Mikrobiologie, Universität Zürich, Zürich, Switzerland
| | - Ann-Kristina Fritz
- Anatomisches Institut, Universität Zürich, Zürich, Switzerland.,Institut für Bewegungswissenschaften und Sport, ETH Zürich, Zürich, Switzerland
| | - Reda Juskeviciene
- Institut für Medizinische Mikrobiologie, Universität Zürich, Zürich, Switzerland
| | - Naoki Oishi
- Department of Otolaryngology, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
| | - Karen Schmitt
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, Universitäre Psychiatrische Kliniken Basel, Basel, Switzerland
| | - Dimitri Shcherbakov
- Institut für Medizinische Mikrobiologie, Universität Zürich, Zürich, Switzerland
| | - Youjin Teo
- Institut für Medizinische Mikrobiologie, Universität Zürich, Zürich, Switzerland
| | - Heithem Boukari
- Institut für Medizinische Mikrobiologie, Universität Zürich, Zürich, Switzerland
| | - Pietro Freihofer
- Institut für Medizinische Mikrobiologie, Universität Zürich, Zürich, Switzerland
| | | | - Björn Oettinghaus
- Neuro- und Ophthalmopathologie, Universitätsspital Basel, Basel, Switzerland
| | - Stephan Frank
- Neuro- und Ophthalmopathologie, Universitätsspital Basel, Basel, Switzerland
| | | | - Hubert Rehrauer
- Functional Genomics Center Zurich, ETH Zürich und Universität Zürich, Zürich, Switzerland
| | - Eric Westhof
- Institut de biologie moléculaire et cellulaire du CNRS, Université de Strasbourg, Strasbourg, France
| | - Jochen Schacht
- Department of Otolaryngology, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, USA
| | - Anne Eckert
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, Universitäre Psychiatrische Kliniken Basel, Basel, Switzerland
| | - David Wolfer
- Anatomisches Institut, Universität Zürich, Zürich, Switzerland.,Institut für Bewegungswissenschaften und Sport, ETH Zürich, Zürich, Switzerland
| | - Erik C Böttger
- Institut für Medizinische Mikrobiologie, Universität Zürich, Zürich, Switzerland
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13
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Subathra M, Ramesh A, Selvakumari M, Karthikeyen NP, Srisailapathy CRS. Genetic Epidemiology of Mitochondrial Pathogenic Variants Causing Nonsyndromic Hearing Loss in a Large Cohort of South Indian Hearing Impaired Individuals. Ann Hum Genet 2017; 80:257-73. [PMID: 27530448 DOI: 10.1111/ahg.12161] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 05/16/2016] [Indexed: 01/28/2023]
Abstract
Mitochondria play a critical role in the generation of metabolic energy in the form of ATP. Tissues and organs that are highly dependent on aerobic metabolism are involved in mitochondrial disorders including nonsyndromic hearing loss (NSHL). Seven pathogenic variants leading to NSHL have so far been reported on two mitochondrial genes: MT-RNR1 encoding 12SrRNA and MT-TS1 encoding tRNA for Ser((UCN)) . We screened 729 prelingual NSHL subjects to determine the prevalence of MT-RNR1 variants at position m.961, m.1555A>G and m.1494C>T, and MT-TS1 m.7445A>G, m.7472insC m.7510T>C and m.7511T>C variants. Mitochondrial pathogenic variants were found in eight probands (1.1%). Five of them were found to have the m.1555A>G variant, two others had m.7472insC and one proband had m.7444G>A. The extended relatives of these probands showed variable degrees of hearing loss and age at onset. This study shows that mitochondrial pathogenic alleles contribute to about 1% prelingual hearing loss. This study will henceforth provide the reference for the prevalence of mitochondrial pathogenic alleles in the South Indian population, which to date has not been estimated. The m.1555A>G variant is a primary predisposing genetic factor for the development of hearing loss. Our study strongly suggests that mitochondrial genotyping should be considered for all hearing impaired individuals and particularly in families where transmission is compatible with maternal inheritance, after ruling out the most common variants.
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Affiliation(s)
- Mahalingam Subathra
- Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India
| | - Arabandi Ramesh
- Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India
| | - Mathiyalagan Selvakumari
- Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India
| | - N P Karthikeyen
- DOAST (Doctrine Oriented Art of Symbiotic Treatment) Hearing Care Center and Integrated Therapy Center for Autism, Anna Nagar West, Chennai, India
| | - C R Srikumari Srisailapathy
- Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India
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14
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Vona B, Nanda I, Shehata-Dieler W, Haaf T. Genetics of Tinnitus: Still in its Infancy. Front Neurosci 2017; 11:236. [PMID: 28533738 PMCID: PMC5421307 DOI: 10.3389/fnins.2017.00236] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 04/10/2017] [Indexed: 12/20/2022] Open
Abstract
Tinnitus is the perception of a phantom sound that affects between 10 and 15% of the general population. Despite this considerable prevalence, treatments for tinnitus are presently lacking. Tinnitus exhibits a diverse array of recognized risk factors and extreme clinical heterogeneity. Furthermore, it can involve an unknown number of auditory and non-auditory networks and molecular pathways. This complex combination has hampered advancements in the field. The identification of specific genetic factors has been at the forefront of several research investigations in the past decade. Nine studies have examined genes in a case-control association approach. Recently, a genome-wide association study has highlighted several potentially significant pathways that are implicated in tinnitus. Two twin studies have calculated a moderate heritability for tinnitus and disclosed a greater concordance rate in monozygotic twins compared to dizygotic twins. Despite the more recent data alluding to genetic factors in tinnitus, a strong association with any specific genetic locus is lacking and a genetic study with sufficient statistical power has yet to be designed. Future research endeavors must overcome the many inherent limitations in previous study designs. This review summarizes the previously embarked upon tinnitus genetic investigations and summarizes the hurdles that have been encountered. The identification of candidate genes responsible for tinnitus may afford gene based diagnostic approaches, effective therapy development, and personalized therapeutic intervention.
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Affiliation(s)
- Barbara Vona
- Institute of Human Genetics, Julius Maximilians University WürzburgWürzburg, Germany
| | - Indrajit Nanda
- Institute of Human Genetics, Julius Maximilians University WürzburgWürzburg, Germany
| | - Wafaa Shehata-Dieler
- Plastic, Aesthetic and Reconstructive Surgery, Department of Otorhinolaryngology, Comprehensive Hearing Center, University Hospital WürzburgWürzburg, Germany
| | - Thomas Haaf
- Institute of Human Genetics, Julius Maximilians University WürzburgWürzburg, Germany
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Balali M, Kamalidehghan B, Farhadi M, Ahmadipour F, Ashkezari MD, Hemami MR, Arabzadeh H, Falah M, Meng GY, Houshmand M. Association of nuclear and mitochondrial genes with audiological examinations in Iranian patients with nonaminoglycoside antibiotics-induced hearing loss. Ther Clin Risk Manag 2016; 12:117-28. [PMID: 26889084 PMCID: PMC4743636 DOI: 10.2147/tcrm.s90581] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Mitochondrial DNA mutations play an important role in causing sensorineural hearing loss. The purpose of this study was to determine the association of the mitochondrial genes RNR1, MT-TL1, and ND1 as well as the nuclear genes GJB2 and GJB6 with audiological examinations in nonfamilial Iranians with cochlear implants, using polymerase chain reaction, DNA sequencing, and RNA secondary structure analysis. We found that there were no novel mutations in the mitochondrial gene 12S rRNA (MT-RNR1) in patients with and without GJB2 mutation (GJB2+ and GJB2−, respectively), but a total of six polymorphisms were found. No mutations were observed in tRNALeu(UUR) (MT-TL1). Furthermore, eight polymorphisms were found in the mitochondrial ND1 gene. Additionally, no mutations were observed in the nuclear GJB6 gene in patients in the GJB2− and GJB2+ groups. The speech intelligibility rating and category of auditory perception tests were statistically assessed in patients in the GJB2− and GJB2+ groups. The results indicated that there was a significant difference (P<0.05) between the categories of auditory perception score in the GJB2− group compared to that in the GJB2+ group. Successful cochlear implantation was observed among individuals with GJB2 mutations (GJB2+) and mitochondrial polymorphisms compared to those without GJB2 mutations (GJB2−). In conclusion, the outcome of this study suggests that variation in the mitochondrial and nuclear genes may influence the penetrance of deafness. Therefore, further genetic and functional studies are required to help patients in making the best choice for cochlear implants.
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Affiliation(s)
- Maryam Balali
- Department of Biology, Islamic Azad University, Ashkezar Branch, Ashkezar, Iran; Department and Research Centre of ENT and Head & Neck Surgery, Iran University of Medical Sciences, Tehran, Iran
| | - Behnam Kamalidehghan
- Medical Genetics Department, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
| | - Mohammad Farhadi
- Department and Research Centre of ENT and Head & Neck Surgery, Iran University of Medical Sciences, Tehran, Iran
| | - Fatemeh Ahmadipour
- Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | | | - Mohsen Rezaei Hemami
- Department and Research Centre of ENT and Head & Neck Surgery, Iran University of Medical Sciences, Tehran, Iran
| | - Hossein Arabzadeh
- Department and Research Centre of ENT and Head & Neck Surgery, Iran University of Medical Sciences, Tehran, Iran
| | - Masoumeh Falah
- Department and Research Centre of ENT and Head & Neck Surgery, Iran University of Medical Sciences, Tehran, Iran
| | - Goh Yong Meng
- Department of Veterinary Preclinical Sciences, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang, Malaysia
| | - Massoud Houshmand
- Medical Genetics Department, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
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16
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Tatar A, Tasdemir S, Sahin I, Bozoglu C, Erdem HB, Yoruk O, Tatar A. Mitochondrial DNA deletions in patients with chronic suppurative otitis media. Eur Arch Otorhinolaryngol 2015; 273:2473-9. [PMID: 26620342 DOI: 10.1007/s00405-015-3839-7] [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: 08/21/2015] [Accepted: 11/18/2015] [Indexed: 11/25/2022]
Abstract
The aim of this study was to investigate the 4977 and 7400 bp deletions of mitochondrial DNA in patients with chronic suppurative otitis media and to indicate the possible association of mitochondrial DNA deletions with chronic suppurative otitis media. Thirty-six patients with chronic suppurative otitis media were randomly selected to assess the mitochondrial DNA deletions. Tympanomastoidectomy was applied for the treatment of chronic suppurative otitis media, and the curettage materials including middle ear tissues were collected. The 4977 and 7400 bp deletion regions and two control regions of mitochondrial DNA were assessed by using the four pair primers. DNA was extracted from middle ear tissues and peripheral blood samples of the patients, and then polymerase chain reactions (PCRs) were performed. PCR products were separated in 2 % agarose gel. Seventeen of 36 patients had the heterozygote 4977 bp deletion in the middle ear tissue but not in peripheral blood. There wasn't any patient who had the 7400 bp deletion in mtDNA of their middle ear tissue or peripheral blood tissue. The patients with the 4977 bp deletion had a longer duration of chronic suppurative otitis media and a higher level of hearing loss than the others (p < 0.01). Long time chronic suppurative otitis media and the reactive oxygen species can cause the mitochondrial DNA deletions and this may be a predisposing factor to sensorineural hearing loss in chronic suppurative otitis media. An antioxidant drug as a scavenger agent may be used in long-term chronic suppurative otitis media.
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Affiliation(s)
- Arzu Tatar
- Department of Otorhinolaryngology, Head and Neck Surgery, Faculty of Medicine, Ataturk University, Erzurum, Turkey.
| | - Sener Tasdemir
- Department of Medical Genetics, Faculty of Medicine, Ataturk University, Erzurum, Turkey
| | - Ibrahim Sahin
- Department of Medical Genetics, Faculty of Medicine, Ataturk University, Erzurum, Turkey
| | - Ceyda Bozoglu
- Department of Molecular Biology, Faculty of Science, Ataturk University, Erzurum, Turkey
| | - Haktan Bagis Erdem
- Department of Medical Genetics, Faculty of Medicine, Ataturk University, Erzurum, Turkey
| | - Ozgur Yoruk
- Department of Otorhinolaryngology, Head and Neck Surgery, Faculty of Medicine, Ataturk University, Erzurum, Turkey
| | - Abdulgani Tatar
- Department of Medical Genetics, Faculty of Medicine, Ataturk University, Erzurum, Turkey
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McKay SE, Yan W, Nouws J, Thormann MJ, Raimundo N, Khan A, Santos-Sacchi J, Song L, Shadel GS. Auditory Pathology in a Transgenic mtTFB1 Mouse Model of Mitochondrial Deafness. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:3132-40. [PMID: 26552864 DOI: 10.1016/j.ajpath.2015.08.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 07/31/2015] [Accepted: 08/14/2015] [Indexed: 12/13/2022]
Abstract
The A1555G mutation in the 12S rRNA gene of human mitochondrial DNA causes maternally inherited, nonsyndromic deafness, an extreme case of tissue-specific mitochondrial pathology. A transgenic mouse strain that robustly overexpresses the mitochondrial 12S ribosomal RNA methyltransferase TFB1M (Tg-mtTFB1 mice) exhibits progressive hearing loss that we proposed models aspects of A1555G-related pathology in humans. Although our previous studies of Tg-mtTFB1 mice implicated apoptosis in the spiral ganglion and stria vascularis because of mitochondrial reactive oxygen species-mediated activation of AMP kinase (AMPK) and the nuclear transcription factor E2F1, detailed auditory pathology was not delineated. Herein, we show that Tg-mtTFB1 mice have reduced endocochlear potential, indicative of significant stria vascularis dysfunction, but without obvious signs of strial atrophy. We also observed decreased auditory brainstem response peak 1 amplitude and prolonged wave I latency, consistent with apoptosis of spiral ganglion neurons. Although no major loss of hair cells was observed, there was a mild impairment of voltage-dependent electromotility of outer hair cells. On the basis of these results, we propose that these events conspire to produce the progressive hearing loss phenotype in Tg-mtTFB1 mice. Finally, genetically reducing AMPK α1 rescues hearing loss in Tg-mtTFB1 mice, confirming that aberrant up-regulation of AMPK signaling promotes the observed auditory pathology. The relevance of these findings to human A1555G patients and the potential therapeutic value of reducing AMPK activity are discussed.
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Affiliation(s)
- Sharen E McKay
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut; Department of Psychology, University of Bridgeport, Bridgeport, Connecticut
| | - Wayne Yan
- Department of Surgery, Yale School of Medicine, New Haven, Connecticut
| | - Jessica Nouws
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut
| | | | - Nuno Raimundo
- Institute of Cell Biology, University Medical Center Göettingen, Göttingen, Germany
| | - Abdul Khan
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut
| | - Joseph Santos-Sacchi
- Department of Surgery, Yale School of Medicine, New Haven, Connecticut; Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut; Department of Neurobiology, Yale School of Medicine, New Haven, Connecticut.
| | - Lei Song
- Department of Surgery, Yale School of Medicine, New Haven, Connecticut.
| | - Gerald S Shadel
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut; Department of Genetics, Yale School of Medicine, New Haven, Connecticut.
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Ibekwe TS, Bhimrao SK, Westerberg BD, Kozak FK. A meta-analysis and systematic review of the prevalence of mitochondrially encoded 12S RNA in the general population: Is there a role for screening neonates requiring aminoglycosides? Afr J Paediatr Surg 2015; 12:105-13. [PMID: 26168747 PMCID: PMC4955414 DOI: 10.4103/0189-6725.160342] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND This was a meta-analysis and systematic review to determine the global prevalence of the mitochondrially encoded 12S RNA (MT-RNR1) genetic mutation in order to assess the need for neonatal screening prior to aminoglycoside therapy. MATERIALS AND METHODS A comprehensive search of MEDLINE, EMBASE, Ovid, Database of Abstracts of Reviews of Effect, Cochrane Library, Clinical Evidence and Cochrane Central Register of Trials was performed including cross-referencing independently by 2 assessors. Selections were restricted to human studies in English. Meta-analysis was done with MetaXL 2013. RESULTS Forty-five papers out of 295 met the criteria. Pooled prevalence in the general population for MT-RNR1 gene mutations (A1555G, C1494T, A7445G) was 2% (1-4%) at 99%. CONCLUSION Routine screening for MT-RNR1 mutations in the general population prior to treatment with aminoglycosides appear desirable but poorly supported by the weak level of evidence available in the literature. Routine screening in high-risk (Chinese and Spanish) populations appear justified.
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Affiliation(s)
- Titus S Ibekwe
- Department of ENT, University of Abuja Teaching Hospital and College of Health Sciences, University of Abuja, Abuja, Nigeria
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Subathra M, Selvakumari M, Ramesh A, Ramakrishnan R, Karan KR, Kaur M, Manikandan M, Srikumari Srisailapathy CR. Complete mitochondrial genome analysis and clinical documentation of a five-generational Indian family with mitochondrial 1555A>G mutation and postlingual hearing loss. Ann Hum Genet 2014; 78:217-34. [PMID: 24660976 DOI: 10.1111/ahg.12061] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 02/11/2014] [Indexed: 11/26/2022]
Abstract
Hearing loss is the most common sensory disorder and is genetically heterogeneous. Apart from nuclear gene mutations, a number of inherited mitochondrial mutations have also been implicated. The m.1555A>G mutation in the mitochondrial MT-RNR1 gene is reported as the most common mutation causing nonsyndromic hearing loss in various ethnic populations. We report here for the first time the clinical, genetic and molecular characterisation of a single large five-generational Tamil-speaking South Indian family with maternally inherited nonsyndromic postlingual hearing loss. Molecular analysis led to identification of m.1555A>G in 28 maternal relatives with variable degree of phenotypic expression. The penetrance of hearing loss among the maternal relatives in this family was 55%. Sequence analysis of the complete mitochondrial genome in 36 members of this pedigree identified 25 known variants and one novel variant co-transmitted along with m.1555A>G mutation. The mtDNA haplotype analysis revealed that the maternal relatives carry the R*T2 haplotype similar to Europeans and South Asians. Sequencing of the coding exon of GJB2 nuclear gene did not show any pathogenic mutations. The results suggest that other nuclear or environmental modifying factors could have played a role in the differential expression of mutation m.1555A>G in postlingual hearing loss in this family.
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Affiliation(s)
- Mahalingam Subathra
- Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India
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Guaran V, Astolfi L, Castiglione A, Simoni E, Olivetto E, Galasso M, Trevisi P, Busi M, Volinia S, Martini A. Association between idiopathic hearing loss and mitochondrial DNA mutations: a study on 169 hearing-impaired subjects. Int J Mol Med 2013; 32:785-94. [PMID: 23969527 PMCID: PMC3812239 DOI: 10.3892/ijmm.2013.1470] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 06/24/2013] [Indexed: 11/16/2022] Open
Abstract
Mutations in mitochondrial DNA (mtDNA) have been shown to be an important cause of sensorineural hearing loss (SNHL). In this study, we performed a clinical and genetic analysis of 169 hearing-impaired patients and some of their relatives suffering from idiopathic SNHL, both familial and sporadic. The analysis of four fragments of their mtDNA identified several polymorphisms, the well known pathogenic mutation, A1555G, and some novel mutations in different genes, implying changes in the aminoacidic sequence. A novel sporadic mutation in 12S rRNA (MT-RNR1), not previously reported in the literature, was found in a case of possible aminoglycoside-induced progressive deafness.
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Affiliation(s)
- Valeria Guaran
- Bioacoustics Research Laboratory, Department of Neurosciences, University of Padua, I-35129 Padua, Italy.
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Vele O, Schrijver I. Inherited hearing loss: molecular genetics and diagnostic testing. ACTA ACUST UNITED AC 2013; 2:231-48. [PMID: 23495655 DOI: 10.1517/17530059.2.3.231] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Hearing loss is a clinically and genetically heterogeneous condition with major medical and social consequences. It affects up to 8% of the general population. OBJECTIVE This review recapitulates the principles of auditory physiology and the molecular basis of hearing loss, outlines the main types of non-syndromic and syndromic deafness by mode of inheritance, and provides an overview of current clinically available genetic testing. METHODS This paper reviews the literature on auditory physiology and on genes, associated with hearing loss, for which genetic testing is presently offered. RESULTS/CONCLUSION The advent of molecular diagnostic assays for hereditary hearing loss permits earlier detection of the underlying causes, facilitates appropriate interventions, and is expected to generate the data necessary for more specific genotype-phenotype correlations.
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Affiliation(s)
- Oana Vele
- Stanford University School of Medicine, Department of Pathology and Pediatrics, L235, 300 Pasteur Drive, Stanford, CA 94305, USA +1 650 724 2403 ; +1 650 724 1567 ;
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A novel MT-CO1 m.6498C>A variation associated with the m.7444G>A mutation in the mitochondrial COI/tRNASer(UCN) genes in a patient with hearing impairment, diabetes and congenital visual loss. Biochem Biophys Res Commun 2013; 430:585-91. [DOI: 10.1016/j.bbrc.2012.11.109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Accepted: 11/19/2012] [Indexed: 11/18/2022]
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Montazer Zohour M, Tabatabaiefar MA, Dehkordi FA, Farrokhi E, Akbari MT, Chaleshtori MH. Large-scale screening of mitochondrial DNA mutations among Iranian patients with prelingual nonsyndromic hearing impairment. Genet Test Mol Biomarkers 2011; 16:271-8. [PMID: 22077646 DOI: 10.1089/gtmb.2011.0176] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Hereditary hearing impairment (HI) is a genetically heterogeneous disorder caused by mutations either in nuclear DNA (nDNA) or in mitochondrial DNA (mtDNA). The nDNA mutations account for the majority of prelingual nonsyndromic HI (NSHI). The present survey was conducted to screen for known pathogenic mtDNA mutations including A1555G, A3243G, C1494T, and A7445G to provide an accurate estimate of their prevalence in prelingual NSHI for the first time in the Iranian subpopulations. One thousand unrelated probands with NSHI (including both GJB2-negative and GJB2 heterozygote cases) and 1000 healthy matched controls were investigated using the PCR/RFLP method followed by DNA sequencing to confirm the observed mtDNA mutations. Two of the studied mutations, namely A3243G and A7445G, were each found in a single family (a frequency of 0.1% for each). Mutation screening for A3243G followed by DNA sequencing led to the identification of G3316A substitution, with no prior link to HI. Surprisingly, screening for A3243G in the studied population identified 6 cases (0.6%) in probands and 10 (1%) in normal subjects. A1555G, the most common mtDNA mutation associated with deafness in other populations, was not found in the studied samples. To conclude, our findings indicate G3316A as a nonpathogenic variant in the prelingual NSHI subpopulations of Iran and suggest that mtDNA mutations do not play a major role in the etiology of NSHI in Iran.
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Affiliation(s)
- Mostafa Montazer Zohour
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
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Kabahuma RI, Ouyang X, Du LL, Yan D, Hutchin T, Ramsay M, Penn C, Liu XZ. Absence of GJB2 gene mutations, the GJB6 deletion (GJB6-D13S1830) and four common mitochondrial mutations in nonsyndromic genetic hearing loss in a South African population. Int J Pediatr Otorhinolaryngol 2011; 75:611-7. [PMID: 21392827 PMCID: PMC4303037 DOI: 10.1016/j.ijporl.2011.01.029] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 01/19/2011] [Accepted: 01/21/2011] [Indexed: 10/18/2022]
Abstract
OBJECTIVE The purpose of this study was to determine the prevalence of mutations in the GJB2 gene, the GJB6-D13S1830 deletion and the four common mitochondrial mutations (A1555G, A3243G, A7511C and A7445G) in a South African population. METHODS Using single-strand conformation polymorphism and direct sequencing for screening GJB2 mutation; Multiplex PCR Amplification for GJB6-D13S1830 deletion and Restriction Fragment-Length Polymorphism (PCR-RFLP) analysis for the four common mtDNA mutations. We screened 182 hearing impaired students to determine the frequency of these mutations in the population. RESULTS None of the reported disease causing mutations in GJB2 nor any novel pathogenic mutations in the coding region were detected, in contrast to the findings among Caucasians. The GJB6-D13S1830 deletion and the mitochondrial mutations were not observed in this group. CONCLUSION These results suggest that GJB2 may not be a significant deafness gene among sub-Saharan Africans, pointing to other unidentified genes as responsible for nonsyndromic hearing loss in these populations.
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Affiliation(s)
- Rosemary I. Kabahuma
- Department of Speech Pathology and Audiology, University of Witwatersrand, Johannesburg, South Africa,Division of Human Genetics, National Health Laboratory Service and School of Pathology, University of Witwatersrand, Johannesburg, South Africa,Department of Otorhinolaryngology, Polokwane/Mankweng Hospital Complex, Polokwane, Limpopo Province, South Africa
| | - Xiaomei Ouyang
- Department of Otolaryngology, University of Miami, Miami, FL, USA
| | - Li Lin Du
- Department of Otolaryngology, University of Miami, Miami, FL, USA
| | - Denise Yan
- Department of Otolaryngology, University of Miami, Miami, FL, USA
| | - Tim Hutchin
- Birmingham Children’s Hospital, Birmingham, UK
| | - Michele Ramsay
- Division of Human Genetics, National Health Laboratory Service and School of Pathology, University of Witwatersrand, Johannesburg, South Africa,Corresponding author at: Division of Human Genetics, National Health Laboratory Service and School of Pathology, University of Witwatersrand, PO Box 1038, Johannesburg 2000, South Africa. Tel.: +27 011 489 9214; fax: +27 011 498 9226. (M. Ramsay)
| | - Claire Penn
- Department of Speech Pathology and Audiology, University of Witwatersrand, Johannesburg, South Africa
| | - Xue-Zhong Liu
- Department of Otolaryngology, University of Miami, Miami, FL, USA,Corresponding author at: Department of Otolaryngology (D-48), University of Miami, 1666 NW 12th Avenue, Miami, FL 33136, USA. Tel.: +1 305 243 5695; fax: +1 305 243 4925. (X.-Z. Liu)
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Verge B, Alonso Y, Valero J, Miralles C, Vilella E, Martorell L. Mitochondrial DNA (mtDNA) and schizophrenia. Eur Psychiatry 2010; 26:45-56. [PMID: 20980130 DOI: 10.1016/j.eurpsy.2010.08.008] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 06/17/2010] [Accepted: 08/22/2010] [Indexed: 11/16/2022] Open
Abstract
The poorly understood aetiology of schizophrenia is known to involve a major genetic contribution even though the genetic factors remain elusive. Most genetic studies are based on Mendelian rules and focus on the nuclear genome, but current studies indicate that other genetic mechanisms are probably involved. This review focuses on mitochondrial DNA (mtDNA), a maternally inherited, 16.6-Kb molecule crucial for energy production that is implicated in numerous human traits and disorders. The aim of this review is to summarise the studies that have explored mtDNA in schizophrenia patients and those which provide evidence for its implication in this illness. Alterations in mitochondrial morphometry, brain energy metabolism, and enzymatic activity in the mitochondrial respiratory chain suggest a mitochondrial dysfunction in schizophrenia that could be related to the genetic characteristics of mtDNA. Moreover, evidence of maternal inheritance and the presence of schizophrenia symptoms in patients suffering from a mitochondrial disorder related to an mtDNA mutation suggest that mtDNA is involved in schizophrenia. The association of specific variants has been reported at the molecular level; however, additional studies are needed to determine whether the mitochondrial genome is involved in schizophrenia.
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Affiliation(s)
- B Verge
- Unitat de Psiquiatria, Facultat de Medicina i Ciències de la Salut, Hospital Psiquiàtric, Universitari Institut Pere Mata, IISPV, Universitat Rovira i Virgili, C/Sant Llorenç 21, 43201 Reus, Spain
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Matt T, Akbergenov R, Shcherbakov D, Böttger EC. The Ribosomal A-site: Decoding, Drug Target, and Disease. Isr J Chem 2010. [DOI: 10.1002/ijch.201000003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kato T, Nishigaki Y, Noguchi Y, Ueno H, Hosoya H, Ito T, Kimura Y, Kitamura K, Tanaka M. Extensive and rapid screening for major mitochondrial DNA point mutations in patients with hereditary hearing loss. J Hum Genet 2010; 55:147-54. [DOI: 10.1038/jhg.2009.143] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Aminoglycoside ototoxicity in Nicaraguan children: patient risk factors and mitochondrial DNA results. Otolaryngol Head Neck Surg 2009; 140:103-7. [PMID: 19130971 DOI: 10.1016/j.otohns.2008.09.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2008] [Revised: 09/30/2008] [Accepted: 09/30/2008] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Aminoglycoside ototoxicity remains a major problem in developing countries and accounts for 3 percent to 30 percent of hearing loss. This high prevalence rate may be related to genetic susceptibility from mitochondrial mutations in the 12S rRNA gene, comorbidity factors, or unregulated use of the medication. This study investigates the risk factors and prevalence of mtDNA mutations in serum from rural Nicaragua children with aminoglycoside-related hearing loss. STUDY DESIGN Cross sectional study. SUBJECTS Deaf children from rural Nicaragua. METHODS Mitochondrial DNA isolated from serum collected from 31 deaf children with childhood or in utero exposure to gentamicin was amplified, sequenced, and analyzed for mutations in the 12S rRNA gene. RESULTS No known pathologic mutations of the 12S rRNA gene were identified in this subpopulation of deaf children. In addition, patients with gentamicin exposure were often likely to have other comorbidity factors. CONCLUSION These results suggest that genetic susceptibility is not a major factor in the high rate of gentamicin ototoxicity in this population sample. The high prevalence of gentamicin ototoxicty in this population is presumed to be due to unrestricted access to the drug.
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Mitochondrial deafness alleles confer misreading of the genetic code. Proc Natl Acad Sci U S A 2008; 105:3244-9. [PMID: 18308926 DOI: 10.1073/pnas.0707265105] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Despite the fact that important genetic diseases are caused by mutant mitochondrial ribosomes, the molecular mechanisms by which such ribosomes result in a clinical phenotype remain largely unknown. The absence of experimental models for mitochondrial diseases has also prevented the rational search for therapeutic interventions. Here, we report on the construction of bacterial hybrid ribosomes that contain various versions of the mitochondrial decoding region of ribosomal RNA. We show that the pathogenic mutations A1555G and C1494T decrease the accuracy of translation and render the ribosomal decoding site hypersusceptible to aminoglycoside antibiotics. This finding suggests misreading of the genetic code as an important molecular mechanism in disease pathogenesis.
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Mitochondrial non-syndromic sensorineural hearing loss: a clinical, audiological and pathological study from Italy, and revision of the literature. Biosci Rep 2008; 28:49-59. [DOI: 10.1042/bsr20070027] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Over the last decade, a number of distinct mutations in the mtDNA (mitochondrial DNA) have been found to be associated with both syndromic and non-syndromic forms of hearing impairment. Their real incidence as a cause of deafness is poorly understood and generally underestimated. Among the known mtDNA mutations, the A1555G mutation in the 12S gene has been identified to be one of the most common genetic cause of deafness, and it has been described to be both associated to non-syndromic progressive SNHL (sensorineural hearing loss) and to aminoglycoside-induced SNHL. In the present study, we have investigated the presence of mtDNA alterations in patients affected by idiopathic non-syndromic SNHL, both familiar and sporadic, in order to evaluate the frequency of mtDNA alterations as a cause of deafness and to describe the audiological manifestations of mitochondrial non-syndromic SNHL. In agreement with previous studies, we found the A1555G mutation to be responsible for a relevant percentage (5.4%) of cases affected with isolated idiopathic sensorineural hearing impairment.
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Abstract
Non-syndromic deafness can be caused by mutations in both nuclear and mitochondrial genes. More than 50 nuclear genes have been shown to be involved in non-syndromic hearing loss, but mutations in mitochondrial DNA (mtDNA) might also cause hearing impairment. As mitochondria are responsible for oxidative phosphorylation, the primary energy-producing system in all eukaryotic cells, mitochondrial dysfunction has pleiotropic effects. Many mutations in mtDNA can lead to multisystem disorders, such as Kearns-Sayre syndrome, NARP, MELAS, or MERRF syndromes, the presentation of which may include hearing loss. A more specific association of mitochondrially inherited deafness and diabetes known as MIDD syndrome can be caused by a limited number of specific mitochondrial mutations. In addition, several rare mutations in the mitochondrial MTTS1 and MTRNR1 genes have been found to be responsible for non-syndromic hearing loss. The most frequent form of non-syndromic deafness is presbyacusis, affecting more than 50% of the elderly. This age-related hearing loss is a paradigm for multifactorial inheritance, involving a multitude of inherited and acquired mutations in the nuclear and mitochondrial genomes, each with a low penetrance, in complex interplay with environmental factors, such as ototoxic medication, that accumulate with age. This study reviews the different mitochondrial mutations, leading to syndromic and especially non-syndromic deafness.
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Affiliation(s)
- H Kokotas
- Department of Genetics, Institute of Child Health, Athens, Greece
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Abstract
The human ear is a delicate sensory apparatus of hearing for normal communication, and its proper functioning is highly dependent on mitochondrial oxidative phosphorylation. The first mitochondrial point mutation for nonsyndromic and aminoglycoside-induced hearing loss was identified in 1993. Since then a number of inherited mitochondrial mutations have been implicated in hearing loss. Most of the molecular defects responsible for mitochondrial disorder-associated hearing loss are mutations in the 12S rRNA gene and tRNA genes. In this review, after a short description of normal hearing mechanisms and mitochondrial genetics, we outline the recent advances that have been made in the identification of deafness-associated mitochondrial mutations, and discuss how mitochondrial dysfunction contributes to hearing loss.
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Affiliation(s)
- Guangqian Xing
- Department of Otolaryngology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China.
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