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Gao F, Schon KR, Vandrovcova J, Wilson L, Hanna MG, Çavdarlı B, Heckmann J, Chinnery PF, Horvath R. Mitochondrial DNA disorders in neuromuscular diseases in diverse populations. Ann Clin Transl Neurol 2024. [PMID: 39095335 DOI: 10.1002/acn3.52141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 06/21/2024] [Accepted: 06/24/2024] [Indexed: 08/04/2024] Open
Abstract
Neuromuscular features are common in mitochondrial DNA (mtDNA) disorders. The genetic architecture of mtDNA disorders in diverse populations is poorly understood. We analysed mtDNA variants from whole-exome sequencing data in neuromuscular patients from South Africa, Brazil, India, Turkey and Zambia. In 998 individuals, there were two definite diagnoses, two possible diagnoses and eight secondary findings. Surprisingly, common pathogenic mtDNA variants found in people of European ancestry were very rare. Whole-exome or -genome sequencing from undiagnosed patients with neuromuscular symptoms should be re-analysed for mtDNA variants, but the landscape of pathogenic mtDNA variants differs around the world.
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Affiliation(s)
- Fei Gao
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Katherine R Schon
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
- Academic Department of Medical Genetics, University of Cambridge, Cambridge, UK
| | - Jana Vandrovcova
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Lindsay Wilson
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Michael G Hanna
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Büşranur Çavdarlı
- Department of Medical Genetics, Ankara Bilkent City Hospital, Ankara, Turkey
- Faculty of Medicine, Department of Medical Genetics, Ankara Yıldırım Beyazıt University, Ankara, Turkey
| | - Jeannine Heckmann
- Neuroscience Institute, University of Cape Town, Cape Town, South Africa
- Division of Neurology, Department of Medicine, Groote Schuur Hospital, Cape Town, South Africa
| | - Patrick F Chinnery
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Rita Horvath
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
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Akar HT, Sayar E, Sarıtaş Nakip Ö, Sönmez E, Özkan MB, Olgaç A. Leigh Syndrome due to MT-ATP6 Variants: A Case Presentation and the Review of the Literature. Mol Syndromol 2024; 15:333-338. [PMID: 39119452 PMCID: PMC11305691 DOI: 10.1159/000536676] [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: 12/30/2023] [Accepted: 02/04/2024] [Indexed: 08/10/2024] Open
Abstract
Introduction Leigh syndrome is a rare mitochondrial disorder characterized by subacute necrotizing encephalomyelopathy, resulting from defects in mitochondrial respiratory enzymes or pyruvate dehydrogenase complex. Symptoms can manifest in infancy, childhood, or adulthood. We present a case of a 7-month-old girl initially misdiagnosed with septic shock but was later found to have Leigh encephalomyelopathy due to MT-ATP6 deficiency. Case Presentation A 7-month-old girl was admitted with fever, drowsiness, and wheezing, initially diagnosed with septic shock. She had a history of parental consanguinity and hypotonia. Physical examination revealed unconsciousness, miotic pupils, and respiratory distress. Initial laboratory tests showed significant metabolic acidosis and elevated lactate, creatine kinase, and ammonia levels. The patient was treated for sepsis and shock, but her condition worsened with elevated lactate and liver transaminases, eventually leading to hypertrophic cardiomyopathy and multiorgan failure. Her basic metabolic scans showed extremely low citrulline levels, whole-exome sequencing analysis did not show any pathologic change in nuclear genome, and mitochondrial genome analysis revealed an MT-ATP homoplasmic variant. She passed away on the 22nd day of hospitalization. Discussion/Conclusion While mitochondrial disorders are broadly acknowledged for their phenotypic diversity, it is essential to note that specific disorders, such as Leigh syndrome, display distinctive presentations with varying degrees of severity. Factors such as the percentage of homoplasmy contribute to the variability in manifestations. Notably, MT-ATP6-associated Leigh syndrome is predominantly characterized by an early onset, typically occurring before the age of 2 years. Low citrulline levels have been observed in approximately 90% of patients with MT-ATP6-related disorders, distinguishing them from other mitochondrial disorders. The exact mechanisms underlying this specific metabolic alteration are not fully understood, but it could be linked to disruptions in the mitochondrial energy production process. The mitochondria are essential for various metabolic pathways, including the urea cycle, where citrulline is involved. The association between low citrulline levels and MT-ATP6-related disorders raises the possibility of using citrulline as a potential biomarker for disease identification. MT-ATP6 defects should be kept in mind in cases with mitochondrial disease and low plasma citrulline levels.
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Affiliation(s)
- Halil Tuna Akar
- Department of Pediatrics, Pediatric Metabolism Unit, Ankara Etlik City Hospital, Ankara, Turkey
| | - Esra Sayar
- Department of Pediatrics, Pediatric Metabolism Unit, Ankara Etlik City Hospital, Ankara, Turkey
| | - Özlem Sarıtaş Nakip
- Department of Pediatrics, Pediatric Intensive Care Unit, Ankara Etlik City Hospital, Ankara, Turkey
| | - Esra Sönmez
- Department of Pediatrics, Ankara Etlik City Hospital, Ankara, Turkey
| | - Mehmet Burak Özkan
- Department of Pediatric Radiology, Ankara Etlik City Hospital, Ankara, Turkey
| | - Asburçe Olgaç
- Department of Pediatrics, Pediatric Metabolism Unit, Ankara Etlik City Hospital, Ankara, Turkey
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Yang T, Liu Y, Lin Z, Chen F, Zhu L, Zhang L, Zhou B, Li F, Sun H. Altered N6-methyladenosine methylation level in spermatozoa messenger RNA of the male partners is related to unexplained recurrent pregnancy loss. Andrology 2024. [PMID: 38979761 DOI: 10.1111/andr.13678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 05/17/2024] [Accepted: 05/30/2024] [Indexed: 07/10/2024]
Abstract
BACKGROUND Understanding the pathogenesis of unexplained recurrent pregnancy loss is paramount for advancing effective treatments. Various biological processes, including spermatogenesis and embryo development, are tightly regulated by N6-methyladenosine modifications. However, few studies have focused on the impact of sperm N6-methyladenosine modifications on embryonic development. Therefore, we aimed to study altered N6-methyladenosine-mediated messenger RNA methylation modifications in the spermatozoa of male partners from couples experiencing unexplained recurrent pregnancy loss, to identify potential diagnostic markers and explore their potential molecular mechanisms in pregnancy loss and embryogenesis. METHODS Methylated RNA immunoprecipitation (MeRIP) sequencing and RNA sequencing were conducted on the spermatozoa of men from couples in the 'unexplained recurrent pregnancy loss' group (n = 6), and the fertility control group (n = 6). To identify the role of the detected key genes, zebrafish model embryos were studied, and multi-omics (transcriptomics, proteomics, and metabolomics) analyses helped to explore the molecular mechanism of abnormal embryogenesis. FINDINGS Comparing unexplained recurrent pregnancy loss with the fertility control group, 217 N6-methyladenosine peaks were significantly upregulated, and 40 were downregulated in the spermatozoa. The combined analyses of spermatozoa-methylated RNA immunoprecipitation sequencing and RNA sequencing indicated that N6-methyladenosine methylation and the expression of SEMA5A, MT-ATP6, ZNF662, and KDM4C were significantly different. In zebrafish embryos, the altered expression of the four genes increased embryonic mortality and malformations by disturbing several key signaling pathways and zygotic genome activation. INTERPRETATION This study highlights the paternal epigenome, which could be one of the reasons for faulty embryogenesis leading to pregnancy loss. The N6-methyladenosine modification, the most prevalent RNA modification, contributes to the exploration and understanding of the paternal epigenome in the maintenance of pregnancy and fetal growth and development. The four genes identified in this study may serve as potential diagnostic markers and elucidate novel molecular mechanisms of embryogenesis.
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Affiliation(s)
- Tingting Yang
- Department of Andrology/Human Sperm Bank of Sichuan Province, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Yanyan Liu
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
- Department of Medical Genetics, Prenatal Diagnosis Center, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Ziyuan Lin
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
- SCU-CUHK Joint Laboratory for Reproductive Medicine, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Feng Chen
- Department of Andrology/Human Sperm Bank of Sichuan Province, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
- SCU-CUHK Joint Laboratory for Reproductive Medicine, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Lin Zhu
- Department of Nephrology/Hemodialysis Center, West China Hospital, Sichuan University and West China School of Nursing, Sichuan University, Chengdu, China
| | - Lin Zhang
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
- Laboratory of Molecular Translational Medicine, Center for Translational Medicine, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Bin Zhou
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
- Laboratory of Molecular Translational Medicine, Center for Translational Medicine, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Fuping Li
- Department of Andrology/Human Sperm Bank of Sichuan Province, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Huaqin Sun
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
- SCU-CUHK Joint Laboratory for Reproductive Medicine, West China Second University Hospital, Sichuan University, Chengdu, China
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Taub DG, Woolf CJ. Age-dependent small fiber neuropathy: Mechanistic insights from animal models. Exp Neurol 2024; 377:114811. [PMID: 38723859 PMCID: PMC11131160 DOI: 10.1016/j.expneurol.2024.114811] [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: 01/26/2024] [Revised: 04/07/2024] [Accepted: 05/05/2024] [Indexed: 05/28/2024]
Abstract
Small fiber neuropathy (SFN) is a common and debilitating disease in which the terminals of small diameter sensory axons degenerate, producing sensory loss, and in many patients neuropathic pain. While a substantial number of cases are attributable to diabetes, almost 50% are idiopathic. An underappreciated aspect of the disease is its late onset in most patients. Animal models of human genetic mutations that produce SFN also display age-dependent phenotypes suggesting that aging is an important contributor to the risk of development of the disease. In this review we define how particular sensory neurons are affected in SFN and discuss how aging may drive the disease. We also evaluate how animal models of SFN can define disease mechanisms that will provide insight into early risk detection and suggest novel therapeutic interventions.
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Affiliation(s)
- Daniel G Taub
- F. M. Kirby Neurobiology Center and Department of Neurology, Boston Children's Hospital, Boston, MA, USA; Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
| | - Clifford J Woolf
- F. M. Kirby Neurobiology Center and Department of Neurology, Boston Children's Hospital, Boston, MA, USA; Department of Neurobiology, Harvard Medical School, Boston, MA, USA
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de Muijnck C, van Schooneveld MJ, Plomp AS, Rodenburg RJ, van Genderen MM, Boon CJ. Leber's hereditary optic neuropathy like disease in MT-ATP6 variant m.8969G>A. Am J Ophthalmol Case Rep 2024; 34:102070. [PMID: 38756953 PMCID: PMC11096717 DOI: 10.1016/j.ajoc.2024.102070] [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: 12/13/2023] [Revised: 04/15/2024] [Accepted: 04/19/2024] [Indexed: 05/18/2024] Open
Abstract
Purpose To describe a case with Leber's hereditary optic neuropathy (LHON) like optic atrophy in the presence of MT-ATP6 gene variant m.8969G > A. Observations A 20-year-old patient with a history of mild developmental delay, mild cognitive impairment, and positional tremor presented with subacute painless visual loss over a few weeks. Mitochondrial genome sequencing revealed a variant in MT-ATP6, m.8969G > A (p.Ser148Asn). This variant was previously reported in association with mitochondrial myopathy, lactic acidosis, and sideroblastic anemia (MLASA) and with nephropathy, followed by brain atrophy, muscle weakness and arrhythmias, but not with optic atrophy. Conclusions and importance Rare variants in MT-ATP6 can also cause LHON like optic atrophy. It is important to perform further genetic analysis of mitochondrial DNA in genetically unsolved cases suspected of Leber's hereditary optic neuropathy to confirm the clinical diagnosis.
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Affiliation(s)
- Cansu de Muijnck
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, the Netherlands
- Department of Ophthalmology, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Mary J. van Schooneveld
- Department of Ophthalmology, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Astrid S. Plomp
- Department of Human Genetics, Amsterdam University Medical Centers, Amsterdam, the Netherlands
- Amsterdam Reproduction and Development Research Institute, Amsterdam, the Netherlands
| | - Richard J. Rodenburg
- Radboud Center for Mitochondrial Medicine, Departments of Pediatrics and Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Maria M. van Genderen
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, the Netherlands
- Bartiméus Diagnostic Center for Complex Visual Disorders, Zeist, the Netherlands
| | - Camiel J.F. Boon
- Department of Ophthalmology, Amsterdam University Medical Centers, Amsterdam, the Netherlands
- Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
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Sala D, Marchet S, Nanetti L, Legati A, Mariotti C, Lamantea E, Ghezzi D, Catania A, Lamperti C. A novel MT-ATP6 variant associated with complicated ataxia in two unrelated Italian patients: case report and functional studies. Orphanet J Rare Dis 2024; 19:200. [PMID: 38755691 PMCID: PMC11100036 DOI: 10.1186/s13023-024-03212-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 05/09/2024] [Indexed: 05/18/2024] Open
Abstract
BACKGROUND MT-ATP6 is a mitochondrial gene which encodes for the intramembrane subunit 6 (or A) of the mitochondrial ATP synthase, also known asl complex V, which is involved in the last step of oxidative phosphorylation to produce cellular ATP through aerobic metabolism. Although classically associated with the NARP syndrome, recent evidence highlights an important role of MT-ATP6 pathogenic variants in complicated adult-onset ataxias. METHODS We describe two unrelated patients with adult-onset cerebellar ataxia associated with severe optic atrophy and mild cognitive impairment. Whole mitochondrial DNA sequencing was performed in both patients. We employed patients' primary fibroblasts and cytoplasmic hybrids (cybrids), generated from patients-derived cells, to assess the activity of respiratory chain complexes, oxygen consumption rate (OCR), ATP production and mitochondrial membrane potential. RESULTS In both patients, we identified the same novel m.8777 T > C variant in MT-ATP6 with variable heteroplasmy level in different tissues. We identifed an additional heteroplasmic novel variant in MT-ATP6, m.8879G > T, in the patients with the most severe phenotype. A significant reduction in complex V activity, OCR and ATP production was observed in cybrid clones homoplasmic for the m.8777 T > C variant, while no functional defect was detected in m.8879G > T homoplasmic clones. In addition, fibroblasts with high heteroplasmic levelsof m.8777 T > C variant showed hyperpolarization of mitochondrial membranes. CONCLUSIONS We describe a novel pathogenic mtDNA variant in MT-ATP6 associated with adult-onset ataxia, reinforcing the value of mtDNA screening within the diagnostic workflow of selected patients with late onset ataxias.
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Affiliation(s)
- Daniele Sala
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Silvia Marchet
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Lorenzo Nanetti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Andrea Legati
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Caterina Mariotti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Eleonora Lamantea
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Daniele Ghezzi
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
- Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122, Milan, Italy
| | - Alessia Catania
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy
| | - Costanza Lamperti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126, Milan, Italy.
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Tang-Siegel GG, Maughan DW, Frownfelter MB, Light AR. Mitochondrial DNA Missense Mutations ChrMT: 8981A > G and ChrMT: 6268C > T Identified in a Caucasian Female with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Triggered by the Epstein-Barr Virus. Case Rep Genet 2024; 2024:6475425. [PMID: 38756740 PMCID: PMC11098598 DOI: 10.1155/2024/6475425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 04/23/2024] [Accepted: 04/25/2024] [Indexed: 05/18/2024] Open
Abstract
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a multisystem disabling disease with unclear etiology and pathophysiology, whose typical symptoms include prolonged debilitating recovery from fatigue or postexertional malaise (PEM). Disrupted production of adenosine triphosphate (ATP), the intracellular energy that fuels cellular activity, is a cause for fatigue. Here, we present a long-term case of ME/CFS: a 75-year-old Caucasian female patient, whose symptoms of ME/CFS were clearly triggered by an acute infection of the Epstein-Barr virus 24 years ago (mononucleosis). Before then, the patient was a healthy professional woman. A recent DNA sequence analysis identified missense variants of mitochondrial respiratory chain enzymes, including ATP6 (ChrMT: 8981A > G; Q152R) and Cox1 (ChrMT: 6268C > T; A122V). Protein subunits ATP6 and Cox1 are encoded by mitochondrial DNA outside of the nucleus: the Cox1 gene encodes subunit 1 of complex IV (CIV: cytochrome c oxidase) and the ATP6 gene encodes subunit A of complex V (CV: ATP synthase). CIV and CV are the last two of five essential enzymes that perform the mitochondrial electron transport respiratory chain reaction to generate ATP. Further analysis of the blood sample using transmission electron microscopy demonstrated abnormal, circulating, extracellular mitochondria. These results indicate that the patient had dysfunctional mitochondria, which may contribute directly to her major symptoms, including PEM and neurological and cognitive changes. Furthermore, the identified variants of ATP6 (ChrMT: 8981A > G; Q152R) and Cox1 (ChrMT: 6268C > T; A122V), functioning at a later stage of mitochondrial ATP production, may play a role in the abnormality of the patient's mitochondria and the development of her ME/CFS symptoms.
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Affiliation(s)
- Gaoyan G. Tang-Siegel
- Department of Molecular Physiology and Biophysics, College of Medicine, University of Vermont, Burlington, VT, USA
| | - David W. Maughan
- Department of Molecular Physiology and Biophysics, College of Medicine, University of Vermont, Burlington, VT, USA
| | | | - Alan R. Light
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
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Olszewska M, Malcher A, Stokowy T, Pollock N, Berman AJ, Budkiewicz S, Kamieniczna M, Jackowiak H, Suszynska-Zajczyk J, Jedrzejczak P, Yatsenko AN, Kurpisz M. Effects of Tcte1 knockout on energy chain transportation and spermatogenesis: implications for male infertility. Hum Reprod Open 2024; 2024:hoae020. [PMID: 38650655 PMCID: PMC11035007 DOI: 10.1093/hropen/hoae020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 03/08/2024] [Indexed: 04/25/2024] Open
Abstract
STUDY QUESTION Is the Tcte1 mutation causative for male infertility? SUMMARY ANSWER Our collected data underline the complex and devastating effect of the single-gene mutation on the testicular molecular network, leading to male reproductive failure. WHAT IS KNOWN ALREADY Recent data have revealed mutations in genes related to axonemal dynein arms as causative for morphology and motility abnormalities in spermatozoa of infertile males, including dysplasia of fibrous sheath (DFS) and multiple morphological abnormalities in the sperm flagella (MMAF). The nexin-dynein regulatory complex (N-DRC) coordinates the dynein arm activity and is built from the DRC1-DRC7 proteins. DRC5 (TCTE1), one of the N-DRC elements, has already been reported as a candidate for abnormal sperm flagella beating; however, only in a restricted manner with no clear explanation of respective observations. STUDY DESIGN SIZE DURATION Using the CRISPR/Cas9 genome editing technique, a mouse Tcte1 gene knockout line was created on the basis of the C57Bl/6J strain. The mouse reproductive potential, semen characteristics, testicular gene expression levels, sperm ATP, and testis apoptosis level measurements were then assessed, followed by visualization of N-DRC proteins in sperm, and protein modeling in silico. Also, a pilot genomic sequencing study of samples from human infertile males (n = 248) was applied for screening of TCTE1 variants. PARTICIPANTS/MATERIALS SETTING METHODS To check the reproductive potential of KO mice, adult animals were crossed for delivery of three litters per caged pair, but for no longer than for 6 months, in various combinations of zygosity. All experiments were performed for wild-type (WT, control group), heterozygous Tcte1+/- and homozygous Tcte1-/- male mice. Gross anatomy was performed on testis and epididymis samples, followed by semen analysis. Sequencing of RNA (RNAseq; Illumina) was done for mice testis tissues. STRING interactions were checked for protein-protein interactions, based on changed expression levels of corresponding genes identified in the mouse testis RNAseq experiments. Immunofluorescence in situ staining was performed to detect the N-DRC complex proteins: Tcte1 (Drc5), Drc7, Fbxl13 (Drc6), and Eps8l1 (Drc3) in mouse spermatozoa. To determine the amount of ATP in spermatozoa, the luminescence level was measured. In addition, immunofluorescence in situ staining was performed to check the level of apoptosis via caspase 3 visualization on mouse testis samples. DNA from whole blood samples of infertile males (n = 137 with non-obstructive azoospermia or cryptozoospermia, n = 111 samples with a spectrum of oligoasthenoteratozoospermia, including n = 47 with asthenozoospermia) was extracted to perform genomic sequencing (WGS, WES, or Sanger). Protein prediction modeling of human-identified variants and the exon 3 structure deleted in the mouse knockout was also performed. MAIN RESULTS AND THE ROLE OF CHANCE No progeny at all was found for the homozygous males which were revealed to have oligoasthenoteratozoospermia, while heterozygous animals were fertile but manifested oligozoospermia, suggesting haploinsufficiency. RNA-sequencing of the testicular tissue showed the influence of Tcte1 mutations on the expression pattern of 21 genes responsible for mitochondrial ATP processing or linked with apoptosis or spermatogenesis. In Tcte1-/- males, the protein was revealed in only residual amounts in the sperm head nucleus and was not transported to the sperm flagella, as were other N-DRC components. Decreased ATP levels (2.4-fold lower) were found in the spermatozoa of homozygous mice, together with disturbed tail:midpiece ratios, leading to abnormal sperm tail beating. Casp3-positive signals (indicating apoptosis) were observed in spermatogonia only, at a similar level in all three mouse genotypes. Mutation screening of human infertile males revealed one novel and five ultra-rare heterogeneous variants (predicted as disease-causing) in 6.05% of the patients studied. Protein prediction modeling of identified variants revealed changes in the protein surface charge potential, leading to disruption in helix flexibility or its dynamics, thus suggesting disrupted interactions of TCTE1 with its binding partners located within the axoneme. LARGE SCALE DATA All data generated or analyzed during this study are included in this published article and its supplementary information files. RNAseq data are available in the GEO database (https://www.ncbi.nlm.nih.gov/geo/) under the accession number GSE207805. The results described in the publication are based on whole-genome or exome sequencing data which includes sensitive information in the form of patient-specific germline variants. Information regarding such variants must not be shared publicly following European Union legislation, therefore access to raw data that support the findings of this study are available from the corresponding author upon reasonable request. LIMITATIONS REASONS FOR CAUTION In the study, the in vitro fertilization performance of sperm from homozygous male mice was not checked. WIDER IMPLICATIONS OF THE FINDINGS This study contains novel and comprehensive data concerning the role of TCTE1 in male infertility. The TCTE1 gene is the next one that should be added to the 'male infertility list' because of its crucial role in spermatogenesis and proper sperm functioning. STUDY FUNDING/COMPETING INTERESTS This work was supported by National Science Centre in Poland, grants no.: 2015/17/B/NZ2/01157 and 2020/37/B/NZ5/00549 (to M.K.), 2017/26/D/NZ5/00789 (to A.M.), and HD096723, GM127569-03, NIH SAP #4100085736 PA DoH (to A.N.Y.). The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.
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Affiliation(s)
- Marta Olszewska
- Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland
| | - Agnieszka Malcher
- Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland
| | - Tomasz Stokowy
- Scientific Computing Group, IT Division, University of Bergen, Bergen, Norway
| | - Nijole Pollock
- Department of OB/GYN and Reproductive Sciences, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Andrea J Berman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Sylwia Budkiewicz
- Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland
| | | | - Hanna Jackowiak
- Department of Histology and Embryology, Poznan University of Life Sciences, Poznan, Poland
| | | | - Piotr Jedrzejczak
- Division of Infertility and Reproductive Endocrinology, Department of Gynecology, Obstetrics and Gynecological Oncology, Poznan University of Medical Sciences, Poznan, Poland
| | - Alexander N Yatsenko
- Department of OB/GYN and Reproductive Sciences, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Maciej Kurpisz
- Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland
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Citrigno L, Qualtieri A, Cerantonio A, De Benedittis S, Gallo O, Di Palma G, Spadafora P, Cavalcanti F. Genomics landscape of mitochondrial DNA variations in patients from South Italy affected by mitochondriopathies. J Neurol Sci 2024; 457:122869. [PMID: 38215527 DOI: 10.1016/j.jns.2024.122869] [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: 10/09/2023] [Revised: 12/20/2023] [Accepted: 01/04/2024] [Indexed: 01/14/2024]
Abstract
Mitochondrial DNA (mtDNA) is a 16,569 base pairs, double-stranded, circular molecule that contains 37 genes coding for 13 subunits of the respiratory chain plus 2 rRNAs and 22 tRNAs. Mutations in these genes have been identified in patients with a variety of disorders affecting every system in the body. The advent of next generation sequencing technologies has provided the possibility to perform the whole mitochondrial DNA sequencing, allowing the identification of disease-causing pathogenic variants in a single platform. In this study, the whole mtDNA of 100 patients from South Italy affected by mitochondrial diseases was analyzed by using an amplicon-based approach and then the enriched libraries were deeply sequenced on the ION Torrent platform (Thermofisher Scientific Waltham, MA, USA). After bioinformatics analysis and filtering, we were able to find 26 nonsynonymous variants with a MAF <1% that were associated with different pathological phenotypes, expanding the mutational spectrum of these diseases. Moreover, among the new mutations found, we have also analyzed the 3D structure of the MT-ATP6 A200T gene variation in order to confirm suspected functional alterations. This work brings light on new variants possibly associated with several mitochondriopathies in patients from South Italy and confirms that deep sequencing approach, compared to the standard methods, is a reliable and time-cost reducing strategy to detect all the variants present in the mitogenome, making the possibility to create a genomics landscape of mitochondrial DNA variations in human diseases.
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Affiliation(s)
- Luigi Citrigno
- Institute for Biomedical Research and Innovation (IRIB), Department of Biomedical Sciences, National Research Council (CNR), Mangone (CS), Italy.
| | - Antonio Qualtieri
- Institute for Biomedical Research and Innovation (IRIB), Department of Biomedical Sciences, National Research Council (CNR), Mangone (CS), Italy
| | - Annamaria Cerantonio
- Institute for Biomedical Research and Innovation (IRIB), Department of Biomedical Sciences, National Research Council (CNR), Mangone (CS), Italy
| | - Selene De Benedittis
- Institute for Biomedical Research and Innovation (IRIB), Department of Biomedical Sciences, National Research Council (CNR), Mangone (CS), Italy
| | - Olivier Gallo
- Institute for Biomedical Research and Innovation (IRIB), Department of Biomedical Sciences, National Research Council (CNR), Mangone (CS), Italy
| | - Gemma Di Palma
- Institute for Biomedical Research and Innovation (IRIB), Department of Biomedical Sciences, National Research Council (CNR), Mangone (CS), Italy
| | - Patrizia Spadafora
- Institute for Biomedical Research and Innovation (IRIB), Department of Biomedical Sciences, National Research Council (CNR), Mangone (CS), Italy
| | - Francesca Cavalcanti
- Institute for Biomedical Research and Innovation (IRIB), Department of Biomedical Sciences, National Research Council (CNR), Mangone (CS), Italy
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10
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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.
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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.)
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11
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Jose M, Fasaludeen A, Pavuluri H, Rudrabhatla PK, Chandrasekharan SV, Jose J, Banerjee M, Sundaram S, Radhakrishnan A, Menon RN. Metabolic causes of pediatric developmental & epileptic encephalopathies (DEE)- genetic variant analysis in a south Indian cohort. Seizure 2024; 115:20-27. [PMID: 38183824 DOI: 10.1016/j.seizure.2023.12.017] [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: 03/30/2023] [Revised: 12/12/2023] [Accepted: 12/25/2023] [Indexed: 01/08/2024] Open
Abstract
PURPOSE Drug-resistant epilepsy is seen in patients with inborn errors of metabolism and metabolic dysfunction in neurons is crucial to brain disorders associated with psychomotor impairment. Diagnostic rates of metabolic causes of developmental and epileptic encephalopathy (DEE) using next generation sequencing have been rarely studied in literature. METHODS A prospective hospital study was carried out in 384 children with DEE, who underwent genetic testing. Metabolic disorders were evaluated with biochemical blood/urine assays and when required CSF estimations performed. RESULTS A total of 154 pathogenic/likely pathogenic variants in 384 children were identified. Out of 384 children, 89 were clinically suspected to have probable or possible metabolic disorders. Pathogenic/likely pathogenic variants in metabolic genes were identified in 39 out of 89 (43.8 %) and promising VUS in 28 (31.4 %). These included variants for progressive myoclonus epilepsies (21; 53.8 %), DEE with focal/multifocal seizures (8; 20.5 %), generalized epilepsy (5;12.8 %), early myoclonic encephalopathy (2; 5.1 %), LGS (1; 2.6 %) and West syndrome (2; 5.1 %). CONCLUSION Our cohort demonstrates for the first time from the Indian subcontinent that identification of metabolic variants can guide investigations and has therapeutic implications in patients with variable DEE phenotypes. A high utility is noted with regard to diagnosis and prognostication, given the low yield of available biochemical tests, indicating cost-effectiveness of this approach.
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Affiliation(s)
- Manna Jose
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - Alfiya Fasaludeen
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - Harini Pavuluri
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - Pavan Kumar Rudrabhatla
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - Soumya V Chandrasekharan
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - Jithu Jose
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - Moinak Banerjee
- Human Molecular Genetics Laboratory, Rajiv Gandhi Centre for Biotechnology, Trivandrum, Kerala, India
| | - Soumya Sundaram
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - Ashalatha Radhakrishnan
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - Ramshekhar N Menon
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India.
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12
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Emanuelsson EB, Arif M, Reitzner SM, Perez S, Lindholm ME, Mardinoglu A, Daub C, Sundberg CJ, Chapman MA. Remodeling of the human skeletal muscle proteome found after long-term endurance training but not after strength training. iScience 2024; 27:108638. [PMID: 38213622 PMCID: PMC10783619 DOI: 10.1016/j.isci.2023.108638] [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: 08/30/2023] [Revised: 11/09/2023] [Accepted: 12/01/2023] [Indexed: 01/13/2024] Open
Abstract
Exercise training has tremendous systemic tissue-specific health benefits, but the molecular adaptations to long-term exercise training are not completely understood. We investigated the skeletal muscle proteome of highly endurance-trained, strength-trained, and untrained individuals and performed exercise- and sex-specific analyses. Of the 6,000+ proteins identified, >650 were differentially expressed in endurance-trained individuals compared with controls. Strikingly, 92% of the shared proteins with higher expression in both the male and female endurance groups were known mitochondrial. In contrast to the findings in endurance-trained individuals, minimal differences were found in strength-trained individuals and between females and males. Lastly, a co-expression network and comparative literature analysis revealed key proteins and pathways related to the health benefits of exercise, which were primarily related to differences in mitochondrial proteins. This network is available as an interactive database resource where investigators can correlate clinical data with global gene and protein expression data for hypothesis generation.
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Affiliation(s)
- Eric B. Emanuelsson
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Muhammad Arif
- Science for Life Laboratory, KTH – Royal Institute of Technology, 171 77 Stockholm, Sweden
| | - Stefan M. Reitzner
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
- Department of Women’s and Children’s Health, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Sean Perez
- Department of Biology, Pomona College, Claremont, CA 91711, USA
| | - Maléne E. Lindholm
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
- Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Adil Mardinoglu
- Science for Life Laboratory, KTH – Royal Institute of Technology, 171 77 Stockholm, Sweden
- Centre for Host–Microbiome Interactions, Faculty of Dentistry, Oral & Craniofacial Sciences, King’s College London, London WC2R 2LS, UK
| | - Carsten Daub
- Department of Biosciences and Nutrition, Karolinska Institutet, 171 77 Stockholm, Sweden
- Science for Life Laboratory, 171 65 Solna, Sweden
| | - Carl Johan Sundberg
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
- Department of Laboratory Medicine, Karolinska Institutet, 141 52 Huddinge, Sweden
- Department of Learning, Informatics, Management and Ethics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Mark A. Chapman
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
- Department of Integrated Engineering, University of San Diego, San Diego, CA 92110, USA
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13
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Luo H, Sun Y, Wang L, Liu H, Zhao R, Song M, Ge H. Targeting endoplasmic reticulum associated degradation pathway combined with radiotherapy enhances the immunogenicity of esophageal cancer cells. Cancer Biol Ther 2023; 24:2166763. [PMID: 36907982 PMCID: PMC10026871 DOI: 10.1080/15384047.2023.2166763] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 12/15/2022] [Accepted: 01/03/2023] [Indexed: 03/14/2023] Open
Abstract
Immunogenic cell death (ICD) is essential for the activation of immune system against cancer. We aimed to investigate the efficacy of endoplasmic reticulum (ER)-associated protein degradation (ERAD) inhibitors (EerI and NMS-873) in enhancing radiation-induced ICD in esophageal cancer (EC). EC cells were administered with ERAD inhibitors, radiation therapy (RT), and the combination treatment. ICD hallmarks including calreticulin (CALR), adenosine triphosphate (ATP), and high mobility group protein B1 (HMGB1) were detected. The efficacy of ERAD inhibitors combined with RT in stimulating ICD was analyzed. Additionally, the role of ICD hallmarks in immune cell infiltration and patient survival was investigated. Inhibiting ERAD pathways was able to stimulate ICD component emission from dying EC cells in a dose-dependent pattern. Radiation-induced ICD was significantly increased after high doses RT (≥10 Gy). ERAD inhibitor combined with moderate dose RT (≥6 Gy) was capable of stimulating increased ICD in EC cells. Dual therapy could elicit the antitumor immune response by enhancing dendritic cells maturation and phagocytosis. Further investigation revealed a significant correlation between CALR and tumor-infiltrating immune cells. Low expression of ATP and HMGB1 and high expression of CALR were associated with favorable survival in patients with EC. The immunogenicityof EC can be enhanced by ERAD inhibitors combined with moderate doses of RT. ICD hallmark genes, especially CALR, are correlated to immune cell infiltration and clinical outcomes in EC. The present results demonstrated an important method to improve the immunogenicity of EC cells for enhanced antitumor immune response.
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Affiliation(s)
- Hui Luo
- Laboratory of Radiation Oncology, the Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, China
| | - Yanan Sun
- Laboratory of Radiation Oncology, the Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, China
| | - Liuxiang Wang
- Academic of Medical Science, Zhengzhou University, Zhengzhou, China
| | - Hui Liu
- Department of Basic Medicine, China-US (Henan) Hormel Cancer Institute, Zhengzhou, China
| | - Ran Zhao
- Department of Basic Medicine, China-US (Henan) Hormel Cancer Institute, Zhengzhou, China
| | - Mengqiu Song
- Department of Basic Medicine, China-US (Henan) Hormel Cancer Institute, Zhengzhou, China
| | - Hong Ge
- Laboratory of Radiation Oncology, the Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, China
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14
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Jurkute N, Arno G, Webster AR, Yu-Wai-Man P. Whole Genome Sequencing Identifies a Partial Deletion of RTN4IP1 in a Patient With Isolated Optic Atrophy. J Neuroophthalmol 2023; 43:e142-e145. [PMID: 35439212 DOI: 10.1097/wno.0000000000001589] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Neringa Jurkute
- Genetics Department, Moorfields Eye Hospital NHS Foundation Trust (NJ, GA, ARW, PY-W-M), London, United Kingdom; Institute of Ophthalmology (NJ, GA, ARW, PY-W-M), University College London, London, United Kingdom; North Thames Genomic Laboratory Hub, Great Ormond Street Hospital for Children (GA), London, United Kingdom; Cambridge Eye Unit, Addenbrooke's Hospital (PY-W-M), Cambridge University Hospitals, Cambridge, United Kingdom; and John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit (PY-W-M), Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
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15
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Nieto-Panqueva F, Rubalcava-Gracia D, Hamel PP, González-Halphen D. The constraints of allotopic expression. Mitochondrion 2023; 73:30-50. [PMID: 37739243 DOI: 10.1016/j.mito.2023.09.004] [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: 01/19/2023] [Revised: 08/28/2023] [Accepted: 09/18/2023] [Indexed: 09/24/2023]
Abstract
Allotopic expression is the functional transfer of an organellar gene to the nucleus, followed by synthesis of the gene product in the cytosol and import into the appropriate organellar sub compartment. Here, we focus on mitochondrial genes encoding OXPHOS subunits that were naturally transferred to the nucleus, and critically review experimental evidence that claim their allotopic expression. We emphasize aspects that may have been overlooked before, i.e., when modifying a mitochondrial gene for allotopic expression━besides adapting the codon usage and including sequences encoding mitochondrial targeting signals━three additional constraints should be considered: (i) the average apparent free energy of membrane insertion (μΔGapp) of the transmembrane stretches (TMS) in proteins earmarked for the inner mitochondrial membrane, (ii) the final, functional topology attained by each membrane-bound OXPHOS subunit; and (iii) the defined mechanism by which the protein translocator TIM23 sorts cytosol-synthesized precursors. The mechanistic constraints imposed by TIM23 dictate the operation of two pathways through which alpha-helices in TMS are sorted, that eventually determine the final topology of membrane proteins. We used the biological hydrophobicity scale to assign an average apparent free energy of membrane insertion (μΔGapp) and a "traffic light" color code to all TMS of OXPHOS membrane proteins, thereby predicting which are more likely to be internalized into mitochondria if allotopically produced. We propose that the design of proteins for allotopic expression must make allowance for μΔGapp maximization of highly hydrophobic TMS in polypeptides whose corresponding genes have not been transferred to the nucleus in some organisms.
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Affiliation(s)
- Felipe Nieto-Panqueva
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Diana Rubalcava-Gracia
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico; Division of Molecular Metabolism, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Patrice P Hamel
- Department of Molecular Genetics and Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, OH, USA; Vellore Institute of Technology (VIT), School of BioScience and Technology, Vellore, Tamil Nadu, India
| | - Diego González-Halphen
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico.
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16
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Hong S, Kim S, Kim K, Lee H. Clinical Approaches for Mitochondrial Diseases. Cells 2023; 12:2494. [PMID: 37887337 PMCID: PMC10605124 DOI: 10.3390/cells12202494] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 10/18/2023] [Accepted: 10/19/2023] [Indexed: 10/28/2023] Open
Abstract
Mitochondria are subcontractors dedicated to energy production within cells. In human mitochondria, almost all mitochondrial proteins originate from the nucleus, except for 13 subunit proteins that make up the crucial system required to perform 'oxidative phosphorylation (OX PHOS)', which are expressed by the mitochondria's self-contained DNA. Mitochondrial DNA (mtDNA) also encodes 2 rRNA and 22 tRNA species. Mitochondrial DNA replicates almost autonomously, independent of the nucleus, and its heredity follows a non-Mendelian pattern, exclusively passing from mother to children. Numerous studies have identified mtDNA mutation-related genetic diseases. The consequences of various types of mtDNA mutations, including insertions, deletions, and single base-pair mutations, are studied to reveal their relationship to mitochondrial diseases. Most mitochondrial diseases exhibit fatal symptoms, leading to ongoing therapeutic research with diverse approaches such as stimulating the defective OXPHOS system, mitochondrial replacement, and allotropic expression of defective enzymes. This review provides detailed information on two topics: (1) mitochondrial diseases caused by mtDNA mutations, and (2) the mechanisms of current treatments for mitochondrial diseases and clinical trials.
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Affiliation(s)
- Seongho Hong
- Korea Mouse Phenotyping Center, Seoul National University, Seoul 08826, Republic of Korea;
- Department of Medicine, Korea University College of Medicine, Seoul 02708, Republic of Korea
| | - Sanghun Kim
- Laboratory Animal Resource and Research Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju 28116, Republic of Korea;
- College of Veterinary Medicine and Research Institute of Veterinary Medicine, Chungbuk National University, Cheongju 28644, Republic of Korea
| | - Kyoungmi Kim
- Department of Biomedical Sciences, Korea University College of Medicine, Seoul 02841, Republic of Korea
- Department of Physiology, Korea University College of Medicine, Seoul 02841, Republic of Korea
| | - Hyunji Lee
- Department of Medicine, Korea University College of Medicine, Seoul 02708, Republic of Korea
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17
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Clemente-Suárez VJ, Redondo-Flórez L, Beltrán-Velasco AI, Ramos-Campo DJ, Belinchón-deMiguel P, Martinez-Guardado I, Dalamitros AA, Yáñez-Sepúlveda R, Martín-Rodríguez A, Tornero-Aguilera JF. Mitochondria and Brain Disease: A Comprehensive Review of Pathological Mechanisms and Therapeutic Opportunities. Biomedicines 2023; 11:2488. [PMID: 37760929 PMCID: PMC10526226 DOI: 10.3390/biomedicines11092488] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/02/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023] Open
Abstract
Mitochondria play a vital role in maintaining cellular energy homeostasis, regulating apoptosis, and controlling redox signaling. Dysfunction of mitochondria has been implicated in the pathogenesis of various brain diseases, including neurodegenerative disorders, stroke, and psychiatric illnesses. This review paper provides a comprehensive overview of the intricate relationship between mitochondria and brain disease, focusing on the underlying pathological mechanisms and exploring potential therapeutic opportunities. The review covers key topics such as mitochondrial DNA mutations, impaired oxidative phosphorylation, mitochondrial dynamics, calcium dysregulation, and reactive oxygen species generation in the context of brain disease. Additionally, it discusses emerging strategies targeting mitochondrial dysfunction, including mitochondrial protective agents, metabolic modulators, and gene therapy approaches. By critically analysing the existing literature and recent advancements, this review aims to enhance our understanding of the multifaceted role of mitochondria in brain disease and shed light on novel therapeutic interventions.
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Affiliation(s)
- Vicente Javier Clemente-Suárez
- Faculty of Sports Sciences, Universidad Europea de Madrid, Tajo Street, s/n, 28670 Madrid, Spain; (V.J.C.-S.); (J.F.T.-A.)
- Group de Investigación en Cultura, Educación y Sociedad, Universidad de la Costa, Barranquilla 080002, Colombia
| | - Laura Redondo-Flórez
- Department of Health Sciences, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, C/Tajo s/n, Villaviciosa de Odón, 28670 Madrid, Spain
| | - Ana Isabel Beltrán-Velasco
- Psychology Department, Facultad de Ciencias de la Vida y la Naturaleza, Universidad Antonio de Nebrija, 28240 Madrid, Spain
| | - Domingo Jesús Ramos-Campo
- LFE Research Group, Department of Health and Human Performance, Faculty of Physical Activity and Sport Science-INEF, Universidad Politécnica de Madrid, 28040 Madrid, Spain
| | - Pedro Belinchón-deMiguel
- Department of Nursing and Nutrition, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain;
| | | | - Athanasios A. Dalamitros
- Laboratory of Evaluation of Human Biological Performance, School of Physical Education and Sport Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece;
| | - Rodrigo Yáñez-Sepúlveda
- Faculty of Education and Social Sciences, Universidad Andres Bello, Viña del Mar 2520000, Chile;
| | - Alexandra Martín-Rodríguez
- Faculty of Sports Sciences, Universidad Europea de Madrid, Tajo Street, s/n, 28670 Madrid, Spain; (V.J.C.-S.); (J.F.T.-A.)
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18
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Zou W, Zong K, Zhang Z, Shen L, Wang X, Su X, Wang X, Yin T, Liang C, Liu Y, Liang D, Hu C, Cao Y, Ji D. Novel economical, accurate, sensitive, single-cell analytical method for mitochondrial DNA quantification in mtDNA mutation carriers. J Assist Reprod Genet 2023; 40:2197-2209. [PMID: 37462790 PMCID: PMC10440311 DOI: 10.1007/s10815-023-02878-w] [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: 02/20/2023] [Accepted: 06/20/2023] [Indexed: 08/22/2023] Open
Abstract
PURPOSE Although a variety of analytical methods have been developed to detect mitochondrial DNA (mtDNA) heteroplasmy, there are special requirements of mtDNA heteroplasmy quantification for women carrying mtDNA mutations receiving the preimplantation genetic diagnosis (PGD) and prenatal diagnosis (PD) in clinic. These special requirements include various sample types, large sample number, long-term follow-up, and the need for detection of single-cell from biopsied embryos. Therefore, developing an economical, accurate, high-sensitive, and single-cell analytical method for mtDNA heteroplasmy is necessary. METHODS In this study, we developed the Sanger sequencing combined droplet digital polymerase chain reaction (ddPCR) method for mtDNA quantification and compared the results to next-generation sequencing (NGS). A total of seventeen families with twelve mtDNA mutations were recruited in this study. RESULTS The results showed that both Sanger sequencing and ddPCR could be used to analyze the mtDNA heteroplasmy in single-cell samples. There was no statistically significant difference in heteroplasmy levels in common samples with high heteroplasmy (≥ 5%), low heteroplasmy (< 5%), and single-cell samples, either between Sanger sequencing and NGS methods, or between ddPCR and NGS methods (P > 0.05). However, Sanger sequencing was unable to detect extremely low heteroplasmy accurately. But even in samples with extremely low heteroplasmy (0.40% and 0.92%), ddPCR was always able to quantify them. Compared to NGS, Sanger sequencing combined ddPCR analytical methods greatly reduced the cost of sequencing. CONCLUSIONS In conclusion, this study successfully established an economical, accurate, sensitive, single-cell analytical method based on the Sanger sequencing combined ddPCR methods for mtDNA heteroplasmy quantification in a clinical setting.
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Affiliation(s)
- Weiwei Zou
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Kai Zong
- Technical Center of Hefei Customs District, No. 329 Tunxi Road, Hefei, 230022, Anhui, China
| | - Zhikang Zhang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Lingchao Shen
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Xiaolei Wang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Xun Su
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Xin Wang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Tao Yin
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Chunmei Liang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Yajing Liu
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Dan Liang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Chao Hu
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China
| | - Yunxia Cao
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China.
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China.
| | - Dongmei Ji
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230022, Anhui, China.
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract (Anhui Medical University), No. 81 Meishan Road, Hefei, 230032, Anhui, China.
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Baldo MS, Nogueira C, Pereira C, Janeiro P, Ferreira S, Lourenço CM, Bandeira A, Martins E, Magalhães M, Rodrigues E, Santos H, Ferreira AC, Vilarinho L. Leigh Syndrome Spectrum: A Portuguese Population Cohort in an Evolutionary Genetic Era. Genes (Basel) 2023; 14:1536. [PMID: 37628588 PMCID: PMC10454233 DOI: 10.3390/genes14081536] [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: 06/26/2023] [Revised: 07/21/2023] [Accepted: 07/24/2023] [Indexed: 08/27/2023] Open
Abstract
Mitochondrial diseases are the most common inherited inborn error of metabolism resulting in deficient ATP generation, due to failure in homeostasis and proper bioenergetics. The most frequent mitochondrial disease manifestation in children is Leigh syndrome (LS), encompassing clinical, neuroradiological, biochemical, and molecular features. It typically affects infants but occurs anytime in life. Considering recent updates, LS clinical presentation has been stretched, and is now named LS spectrum (LSS), including classical LS and Leigh-like presentations. Apart from clinical diagnosis challenges, the molecular characterization also progressed from Sanger techniques to NGS (next-generation sequencing), encompassing analysis of nuclear (nDNA) and mitochondrial DNA (mtDNA). This upgrade resumed steps and favored diagnosis. Hereby, our paper presents molecular and clinical data on a Portuguese cohort of 40 positive cases of LSS. A total of 28 patients presented mutation in mtDNA and 12 in nDNA, with novel mutations identified in a heterogeneous group of genes. The present results contribute to the better knowledge of the molecular basis of LS and expand the clinical spectrum associated with this syndrome.
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Affiliation(s)
- Manuela Schubert Baldo
- Research and Development Unit, Human Genetics Department, National Institute of Health Doutor Ricardo Jorge, 4000-055 Porto, Portugal; (M.S.B.)
| | - Célia Nogueira
- Research and Development Unit, Human Genetics Department, National Institute of Health Doutor Ricardo Jorge, 4000-055 Porto, Portugal; (M.S.B.)
- Neonatal Screening, Metabolism and Genetics Unit, Human Genetics Department, National Institute of Health Doutor Ricardo Jorge, 4000-055 Porto, Portugal
| | - Cristina Pereira
- Research and Development Unit, Human Genetics Department, National Institute of Health Doutor Ricardo Jorge, 4000-055 Porto, Portugal; (M.S.B.)
- Neonatal Screening, Metabolism and Genetics Unit, Human Genetics Department, National Institute of Health Doutor Ricardo Jorge, 4000-055 Porto, Portugal
| | - Patrícia Janeiro
- Inherited Metabolic Disease Reference Center, Lisbon North University Hospital Center (CHULN), EPE, 1649-028 Lisbon, Portugal
| | - Sara Ferreira
- Inherited Metabolic Disease Reference Center, Pediatric Hospital, Hospital and University Center of Coimbra, 3004-561 Coimbra, Portugal
| | - Charles M. Lourenço
- Neurogenetics Department, Faculdade de Medicina de São Jose do Rio Preto, São Jose do Rio Preto 15090-000, Brazil
| | - Anabela Bandeira
- Oporto Hospital Centre, University of Porto, 4099-001 Porto, Portugal
| | - Esmeralda Martins
- Oporto Hospital Centre, University of Porto, 4099-001 Porto, Portugal
- Unit for Multidisciplinary Research in Biomedicine, Instituto de Ciências Biomédicas Abel Salazar, Porto University, 4050-313 Porto, Portugal
| | - Marina Magalhães
- Department of Neurology Porto Hospital and University Centre, EPE, 4050-011 Porto, Portugal
| | - Esmeralda Rodrigues
- Reference Center for Inherited Metabolic Disorders, University Hospital Centre S. João, 4200-319 Porto, Portugal
| | - Helena Santos
- Department of Pediatrics, Hospital Centre, EPE, 4434-502 Vila Nova de Gaia, Portugal
| | | | - Laura Vilarinho
- Research and Development Unit, Human Genetics Department, National Institute of Health Doutor Ricardo Jorge, 4000-055 Porto, Portugal; (M.S.B.)
- Neonatal Screening, Metabolism and Genetics Unit, Human Genetics Department, National Institute of Health Doutor Ricardo Jorge, 4000-055 Porto, Portugal
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20
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Magistrati M, Gilea AI, Gerra MC, Baruffini E, Dallabona C. Drug Drop Test: How to Quickly Identify Potential Therapeutic Compounds for Mitochondrial Diseases Using Yeast Saccharomyces cerevisiae. Int J Mol Sci 2023; 24:10696. [PMID: 37445873 DOI: 10.3390/ijms241310696] [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: 05/30/2023] [Revised: 06/22/2023] [Accepted: 06/25/2023] [Indexed: 07/15/2023] Open
Abstract
Mitochondrial diseases (MDs) refer to a group of clinically and genetically heterogeneous pathologies characterized by defective mitochondrial function and energy production. Unfortunately, there is no effective treatment for most MDs, and current therapeutic management is limited to relieving symptoms. The yeast Saccharomyces cerevisiae has been efficiently used as a model organism to study mitochondria-related disorders thanks to its easy manipulation and well-known mitochondrial biogenesis and metabolism. It has been successfully exploited both to validate alleged pathogenic variants identified in patients and to discover potential beneficial molecules for their treatment. The so-called "drug drop test", a phenotype-based high-throughput screening, especially if coupled with a drug repurposing approach, allows the identification of molecules with high translational potential in a cost-effective and time-saving manner. In addition to drug identification, S. cerevisiae can be used to point out the drug's target or pathway. To date, drug drop tests have been successfully carried out for a variety of disease models, leading to very promising results. The most relevant aspect is that studies on more complex model organisms confirmed the effectiveness of the drugs, strengthening the results obtained in yeast and demonstrating the usefulness of this screening as a novel approach to revealing new therapeutic molecules for MDs.
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Affiliation(s)
- Martina Magistrati
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
| | - Alexandru Ionut Gilea
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
| | - Maria Carla Gerra
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
| | - Enrico Baruffini
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
| | - Cristina Dallabona
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
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21
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Gedikbasi A, Toksoy G, Karaca M, Gulec C, Balci MC, Gunes D, Gunes S, Aslanger AD, Unverengil G, Karaman B, Basaran S, Demirkol M, Gokcay GF, Uyguner ZO. Clinical and bi-genomic DNA findings of patients suspected to have mitochondrial diseases. Front Genet 2023; 14:1191159. [PMID: 37377599 PMCID: PMC10292751 DOI: 10.3389/fgene.2023.1191159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 05/02/2023] [Indexed: 06/29/2023] Open
Abstract
Background: Mitochondrial diseases are the most common group of inherited metabolic disorders, causing difficulties in definite diagnosis due to clinical and genetic heterogeneity. Clinical components are predominantly associated with pathogenic variants shown in nuclear or mitochondrial genomes that affect vital respiratory chain function. The development of high-throughput sequencing technologies has accelerated the elucidation of the genetic etiology of many genetic diseases that previously remained undiagnosed. Methods: Thirty affected patients from 24 unrelated families with clinical, radiological, biochemical, and histopathological evaluations considered for mitochondrial diseases were investigated. DNA isolated from the peripheral blood samples of probands was sequenced for nuclear exome and mitochondrial DNA (mtDNA) analyses. MtDNA sequencing was also performed from the muscle biopsy material in one patient. For segregation, Sanger sequencing is performed for pathogenic alterations in five other affected family members and healthy parents. Results: Exome sequencing revealed 14 different pathogenic variants in nine genes encoding mitochondrial function peptides (AARS2, EARS2, ECHS1, FBXL4, MICOS13, NDUFAF6, OXCT1, POLG, and TK2) in 12 patients from nine families and four variants in genes encoding important for muscle structure (CAPN3, DYSF, and TCAP) in six patients from four families. Three probands carried pathogenic mtDNA variations in two genes (MT-ATP6 and MT-TL1). Nine variants in five genes are reported for the first time with disease association: (AARS2: c.277C>T/p.(R93*), c.845C>G/p.(S282C); EARS2: c.319C>T/p.(R107C), c.1283delC/p.(P428Lfs*); ECHS1: c.161G>A/p.(R54His); c.202G>A/p.(E68Lys); NDUFAF6: c.479delA/p.(N162Ifs*27); and OXCT1: c.1370C>T/p.(T457I), c.1173-139G>T/p.(?). Conclusion: Bi-genomic DNA sequencing clarified genetic etiology in 67% (16/24) of the families. Diagnostic utility by mtDNA sequencing in 13% (3/24) and exome sequencing in 54% (13/24) of the families prioritized searching for nuclear genome pathologies for the first-tier test. Weakness and muscle wasting observed in 17% (4/24) of the families underlined that limb-girdle muscular dystrophy, similar to mitochondrial myopathy, is an essential point for differential diagnosis. The correct diagnosis is crucial for comprehensive genetic counseling of families. Also, it contributes to making treatment-helpful referrals, such as ensuring early access to medication for patients with mutations in the TK2 gene.
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Affiliation(s)
- Asuman Gedikbasi
- Department of Pediatric Basic Sciences, Institute of Child Health Istanbul University, Istanbul, Türkiye
- Division of Pediatric Nutrition and Metabolism, Department of Pediatrics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Guven Toksoy
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Meryem Karaca
- Division of Pediatric Nutrition and Metabolism, Department of Pediatrics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Cagri Gulec
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Mehmet Cihan Balci
- Division of Pediatric Nutrition and Metabolism, Department of Pediatrics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Dilek Gunes
- Division of Pediatric Nutrition and Metabolism, Department of Pediatrics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Seda Gunes
- Division of Pediatric Nutrition and Metabolism, Department of Pediatrics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Ayca Dilruba Aslanger
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Gokcen Unverengil
- Department of Pathology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Birsen Karaman
- Department of Pediatric Basic Sciences, Institute of Child Health Istanbul University, Istanbul, Türkiye
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Seher Basaran
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Mubeccel Demirkol
- Division of Pediatric Nutrition and Metabolism, Department of Pediatrics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Gulden Fatma Gokcay
- Division of Pediatric Nutrition and Metabolism, Department of Pediatrics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
| | - Zehra Oya Uyguner
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye
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22
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Wongkittichote P, Ganetzky RD, Demczko MM, Hong X, He M, Master SR. Low Plasma Citrulline Guiding the Diagnosis of a Mitochondrial Disorder. Clin Chem 2023; 69:661-664. [PMID: 37258485 DOI: 10.1093/clinchem/hvad039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 03/09/2023] [Indexed: 06/02/2023]
Affiliation(s)
- Parith Wongkittichote
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Rebecca D Ganetzky
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Matthew M Demczko
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Xinying Hong
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Miao He
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Stephen R Master
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
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23
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Malaquias MJ, Igreja L, Nogueira C, Pereira C, Vilarinho L, Quelhas D, Freixo JP, Oliveira J, Magalhães M. Diagnosis across a cohort of "atypical" atypical and complex parkinsonism. Parkinsonism Relat Disord 2023; 111:105408. [PMID: 37105015 DOI: 10.1016/j.parkreldis.2023.105408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/26/2023] [Accepted: 04/16/2023] [Indexed: 04/29/2023]
Abstract
INTRODUCTION The diagnostic approach for adulthood parkinsonism can be challenging when atypical features hamper its classification in one of the two main parkinsonian groups: Parkinson's disease or atypical parkinsonian syndromes (APS). Atypical features are usually associated with non-sporadic neurodegenerative causes. METHODS Retrospective analysis of patients with a working clinical diagnosis of "atypical" APS and complex parkinsonism. "Atypical" APS were classified according to the diagnostic research criteria and the "4-step diagnostic approach" (Stamelou et al. 2013). When not indicated, the final aetiological diagnosis was prospectively assessed. Brain MRI of progressive supranuclear palsy (PSP) look-alikes was reviewed by a neuroradiologist. RESULTS Among 18 patients enrolled, ten were assigned to the "atypical" APS and eight to the complex parkinsonism group. In the "atypical" APS group, nine patients had PSP and one had corticobasal degeneration. In the PSP group the median magnetic resonance parkinsonism index was 17.1. A final aetiological diagnosis was established for 11 patients, four from the complex parkinsonism (L-2-hidroxiglutaric aciduria and DiGeorge syndrome) and seven from the "atypical" APS (Perry syndrome, postencephalitic PSP, vascular PSP, and MTP-AT6 mitochondrial disease) group. CONCLUSIONS In this study, the identification of atypical APS features, as proposed in the "4-step diagnostic approach", successfully guided the investigation of alternative diagnoses. Distinctive non-neurodegenerative etiologies causing "atypical" atypical and complex parkinsonism were uncovered, including acquired (post-encephalitis and vascular) and genetic (MTP-AT6 mitochondrial disease mimicking PSP, described for the first time) ones. In the future, accurate clinical identification and distinction between neurodegenerative and non-neurodegenerative parkinsonism etiologies will allow for refining clinical trials.
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Affiliation(s)
- Maria João Malaquias
- Neurology Department, Centro Hospitalar Universitário de Santo António, Porto, Portugal.
| | - Liliana Igreja
- Neuroradiology Department, Centro Hospitalar Universitário de Santo António, Porto, Portugal
| | - Célia Nogueira
- Newborn Screening, Metabolism and Genetics Unit, Human Genetics Department, National Institute of Health, Porto, Portugal
| | - Cristina Pereira
- Newborn Screening, Metabolism and Genetics Unit, Human Genetics Department, National Institute of Health, Porto, Portugal
| | - Laura Vilarinho
- Newborn Screening, Metabolism and Genetics Unit, Human Genetics Department, National Institute of Health, Porto, Portugal
| | - Dulce Quelhas
- Unidade de Bioquímica Genética, Centro de Genética Médica Doutor Jacinto Magalhães, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - João Parente Freixo
- Center for Predictive and Preventive Genetics (CGPP), Institute for Molecular and Cell Biology (IBMC), Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, Portugal
| | - Jorge Oliveira
- Center for Predictive and Preventive Genetics (CGPP), Institute for Molecular and Cell Biology (IBMC), Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, Portugal
| | - Marina Magalhães
- Neurology Department, Centro Hospitalar Universitário de Santo António, Porto, Portugal
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24
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Baranowska E, Niedzwiecka K, Panja C, Charles C, Dautant A, Poznanski J, di Rago JP, Tribouillard-Tanvier D, Kucharczyk R. Probing the pathogenicity of patient-derived variants of MT-ATP6 in yeast. Dis Model Mech 2023; 16:307138. [PMID: 37083953 PMCID: PMC10151828 DOI: 10.1242/dmm.049783] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 02/28/2023] [Indexed: 04/22/2023] Open
Abstract
The list of mitochondrial DNA (mtDNA) variants detected in individuals with neurodegenerative diseases is constantly growing. Evaluating their functional consequences and pathogenicity is not easy, especially when they are found in only a limited number of patients together with wild-type mtDNA (heteroplasmy). Owing to its amenability to mitochondrial genetic transformation and incapacity to stably maintain heteroplasmy, and the strong evolutionary conservation of the proteins encoded in mitochondria, Saccharomyces cerevisiae provides a convenient model to investigate the functional consequences of human mtDNA variants. We herein report the construction and energy-transducing properties of yeast models of eight MT-ATP6 gene variants identified in patients with various disorders: m.8843T>C, m.8950G>A, m.9016A>G, m.9025G>A, m.9029A>G, m.9058A>G, m.9139G>A and m.9160T>C. Significant defect in growth dependent on respiration and deficits in ATP production were observed in yeast models of m.8950G>A, m.9025G>A and m.9029A>G, providing evidence of pathogenicity for these variants. Yeast models of the five other variants showed very mild, if any, effect on mitochondrial function, suggesting that the variants do not have, at least alone, the potential to compromise human health.
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Affiliation(s)
- Emilia Baranowska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02106 Warsaw, Poland
| | - Katarzyna Niedzwiecka
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02106 Warsaw, Poland
| | - Chiranjit Panja
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02106 Warsaw, Poland
| | - Camille Charles
- University of Bordeaux, Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires, UMR 5095, F-33000 Bordeaux, France
| | - Alain Dautant
- University of Bordeaux, Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires, UMR 5095, F-33000 Bordeaux, France
| | - Jarosław Poznanski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02106 Warsaw, Poland
| | - Jean-Paul di Rago
- University of Bordeaux, Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires, UMR 5095, F-33000 Bordeaux, France
| | - Déborah Tribouillard-Tanvier
- University of Bordeaux, Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires, UMR 5095, F-33000 Bordeaux, France
| | - Roza Kucharczyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02106 Warsaw, Poland
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25
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Tise CG, Verscaj CP, Mendelsohn BA, Woods J, Lee CU, Enns GM, Stander Z, Hall PL, Cowan TM, Cusmano-Ozog KP. MT-ATP6 mitochondrial disease identified by newborn screening reveals a distinct biochemical phenotype. Am J Med Genet A 2023; 191:1492-1501. [PMID: 36883293 DOI: 10.1002/ajmg.a.63159] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 01/24/2023] [Accepted: 02/08/2023] [Indexed: 03/09/2023]
Abstract
Although decreased citrulline is used as a newborn screening (NBS) marker to identify proximal urea cycle disorders (UCDs), it is also a feature of some mitochondrial diseases, including MT-ATP6 mitochondrial disease. Here we describe biochemical and clinical features of 11 children born to eight mothers from seven separate families who were identified with low citrulline by NBS (range 3-5 μM; screening cutoff >5) and ultimately diagnosed with MT-ATP6 mitochondrial disease. Follow-up testing revealed a pattern of hypocitrullinemia together with elevated propionyl-(C3) and 3-hydroxyisovaleryl-(C5-OH) acylcarnitines, and a homoplasmic pathogenic variant in MT-ATP6 in all cases. Single and multivariate analysis of NBS data from the 11 cases using Collaborative Laboratory Integrated Reports (CLIR; https://clir.mayo.edu) demonstrated citrulline <1st percentile, C3 > 50th percentile, and C5-OH >90th percentile when compared with reference data, as well as unequivocal separation from proximal UCD cases and false-positive low citrulline cases using dual scatter plots. Five of the eight mothers were symptomatic at the time of their child(ren)'s diagnosis, and all mothers and maternal grandmothers evaluated molecularly and biochemically had a homoplasmic pathogenic variant in MT-ATP6, low citrulline, elevated C3, and/or elevated C5-OH. All molecularly confirmed individuals (n = 17) with either no symptoms (n = 12), migraines (n = 1), or a neurogenic muscle weakness, ataxia, and retinitis pigmentosa (NARP) phenotype (n = 3) were found to have an A or U mitochondrial haplogroup, while one child with infantile-lethal Leigh syndrome had a B haplogroup.
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Affiliation(s)
- Christina G Tise
- Division of Medical Genetics, Stanford University, Stanford, California, USA
| | - Courtney P Verscaj
- Division of Medical Genetics, Stanford University, Stanford, California, USA
| | - Bryce A Mendelsohn
- Department of Medical Genetics, Kaiser Permanente Northern California, Oakland, California, USA
| | - Jeremy Woods
- Division of Medical Genetics, Stanford University, Stanford, California, USA.,Department of Medical Genetics and Metabolism, Valley Children's Healthcare, Madera, California, USA
| | - Chung U Lee
- Division of Medical Genetics, Stanford University, Stanford, California, USA
| | - Gregory M Enns
- Division of Medical Genetics, Stanford University, Stanford, California, USA
| | - Zinandré Stander
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Patricia L Hall
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Tina M Cowan
- Department of Pathology, Stanford University, Stanford, California, USA
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Abstract
BACKGROUND To describe the clinical presentation with a focus on ocular manifestations and response to riboflavin supplementation of 3 patients with riboflavin transporter deficiency (RTD) caused by mutations in SLC52A2 ( SLC52A2- RTD). METHODS This is a retrospective review of records of 3 children (aged 18, n = 2 and age = 8, n = 1) with SLC52A2- RTD. Patients underwent comprehensive ophthalmic evaluations including color vision testing, pattern visual-evoked potentials (pVEPs, 1 patient) and spectral domain optical coherence tomography (SD-OCT) imaging. Patients received riboflavin supplements from the time of the molecular diagnosis of RTD. RESULTS Two unrelated 18-year-old patients with SLC52A2- RTD had a symptomatic onset with sensorineural hearing loss and auditory neuropathy/dys-synchrony since age 3 and 11, respectively. On examination 7 years after symptomatic onset, they showed subnormal visual acuities (20/30 and 20/60, both eyes, respectively), preserved color vision, and a thin but measurable retinal ganglion cell layer (GCL) and nerve fiber (RNFL). The inner and outer nuclear layers were normal. The asymptomatic SLC52A2- positive brother of one of these patients started riboflavin supplementation right after the molecular diagnosis and had normal vision and SD-OCTs 7 years later. Onset of riboflavin supplementation in one of the 2 symptomatic cases resulted in acute improvement of the pattern visual-evoked potential and vision. CONCLUSIONS Retinal ganglion cells and their axons are uniquely susceptible to RTD compared with other highly energy-dependent retinal neurons, such as photoreceptors, raising the possibility for alternative mechanisms of disease or protection. Riboflavin supplementation results in acute functional improvement of vision and long-term preservation of GCL and RNFL if initiated early.
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27
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Hjelm BE, Ramiro C, Rollins BL, Omidsalar AA, Gerke DS, Das SC, Sequeira A, Morgan L, Schatzberg AF, Barchas JD, Lee FS, Myers RM, Watson SJ, Akil H, Bunney WE, Vawter MP. Large Common Mitochondrial DNA Deletions Are Associated with a Mitochondrial SNP T14798C Near the 3' Breakpoints. Complex Psychiatry 2023; 8:90-98. [PMID: 36778651 PMCID: PMC9909249 DOI: 10.1159/000528051] [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: 05/02/2022] [Accepted: 10/19/2022] [Indexed: 11/16/2022] Open
Abstract
Introduction Large somatic deletions of mitochondrial DNA (mtDNA) accumulate with aging in metabolically active tissues such as the brain. We have cataloged the breakpoints and frequencies of large mtDNA deletions in the human brain. Methods We quantified 112 high-frequency mtDNA somatic deletions across four human brain regions with the Splice-Break2 pipeline. In addition, we utilized PLINK/Seq to test the association of mitochondrial genotypes with the abundance of these high-frequency mtDNA deletions. A conservative p value threshold of 5E-08 was used to find the significant loci. Results One mtDNA SNP (T14798C) was significantly associated with mtDNA deletions in two brain regions, the dorsolateral prefrontal cortex (DLPFC) and the superior temporal gyrus. Since the DLPFC showed the most robust association between T14798C and two deletion breakpoints (7816-14807 and 5462-14807), this association was tested in the DLPFC of a replication sample and validated the first results. Incorporating the C allele at 14,798 bp increased the perfect/imperfect length of the repeat at the 3' breakpoint of the two associated deletions. Conclusion This is the first study to identify the association of mtDNA SNP with large mtDNA deletions in the human brain. The T14798C allele located in the MT-CYB gene is a common polymorphism that occurs in several mitochondrial haplogroups. We hypothesize that the T14798C association with two deletions occurs by extending the repeat length around the 3' deletion breakpoints. This simple mechanism suggests that mtDNA SNPs can affect the mitochondrial genome structure, especially in brain where high levels of reactive oxygen species lead to deletion accumulation with aging.
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Affiliation(s)
- Brooke E. Hjelm
- Department of Translational Genomics, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Christian Ramiro
- Functional Genomics Laboratory, Department of Psychiatry and Human Behavior, University of California, Irvine, California, USA
| | - Brandi L. Rollins
- Functional Genomics Laboratory, Department of Psychiatry and Human Behavior, University of California, Irvine, California, USA
| | - Audrey A. Omidsalar
- Department of Translational Genomics, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Daniel S. Gerke
- Department of Translational Genomics, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Sujan C. Das
- Functional Genomics Laboratory, Department of Psychiatry and Human Behavior, University of California, Irvine, California, USA
| | - Adolfo Sequeira
- Functional Genomics Laboratory, Department of Psychiatry and Human Behavior, University of California, Irvine, California, USA
| | - Ling Morgan
- Functional Genomics Laboratory, Department of Psychiatry and Human Behavior, University of California, Irvine, California, USA
| | - Alan F. Schatzberg
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, California, USA
| | - Jack D. Barchas
- Department of Psychiatry, Weill Cornell Medical College, Ithaca, New York, USA
| | - Francis S. Lee
- Department of Psychiatry, Weill Cornell Medical College, Ithaca, New York, USA
| | - Richard M. Myers
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama, USA
| | - Stanley J. Watson
- The Michigan Neuroscience Institute (MNI), University of Michigan, Ann Arbor, Michigan, USA
| | - Huda Akil
- The Michigan Neuroscience Institute (MNI), University of Michigan, Ann Arbor, Michigan, USA
| | - William E. Bunney
- Department of Psychiatry and Human Behavior, University of California, Irvine, California, USA
| | - Marquis P. Vawter
- Functional Genomics Laboratory, Department of Psychiatry and Human Behavior, University of California, Irvine, California, USA,*Marquis P. Vawter,
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Baranowska E, Niedzwiecka K, Panja C, Charles C, Dautant A, di Rago JP, Tribouillard-Tanvier D, Kucharczyk R. Molecular basis of diseases induced by the mitochondrial DNA mutation m.9032 T > C. Hum Mol Genet 2022; 32:1313-1323. [PMID: 36434790 PMCID: PMC10077503 DOI: 10.1093/hmg/ddac292] [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: 09/05/2022] [Revised: 11/08/2022] [Accepted: 11/22/2022] [Indexed: 11/28/2022] Open
Abstract
The mitochondrial DNA mutation m.9032 T > C was previously identified in patients presenting with NARP (Neuropathy Ataxia Retinitis Pigmentosa). Their clinical features had a maternal transmission and patient's cells showed a reduced oxidative phosphorylation capacity, elevated reactive oxygen species (ROS) production and hyperpolarization of the mitochondrial inner membrane, providing evidence that m.9032 T > C is truly pathogenic. This mutation leads to replacement of a highly conserved leucine residue with proline at position 169 of ATP synthase subunit a (L169P). This protein and a ring of identical c-subunits (c-ring) move protons through the mitochondrial inner membrane coupled to ATP synthesis. We herein investigated the consequences of m.9032 T > C on ATP synthase in a strain of Saccharomyces cerevisiae with an equivalent mutation (L186P). The mutant enzyme assembled correctly but was mostly inactive as evidenced by a > 95% drop in the rate of mitochondrial ATP synthesis and absence of significant ATP-driven proton pumping across the mitochondrial membrane. Intragenic suppressors selected from L186P yeast restoring ATP synthase function to varying degrees (30-70%) were identified at the original mutation site (L186S) or in another position of the subunit a (H114Q, I118T). In light of atomic structures of yeast ATP synthase recently described, we conclude from these results that m.9032 T > C disrupts proton conduction between the external side of the membrane and the c-ring, and that H114Q and I118T enable protons to access the c-ring through a modified pathway.
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Affiliation(s)
- Emilia Baranowska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Katarzyna Niedzwiecka
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Chiranjit Panja
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Camille Charles
- Univ. Bordeaux, CNRS, IBGC, UMR 5095, F-33000 Bordeaux, France
| | - Alain Dautant
- Univ. Bordeaux, CNRS, IBGC, UMR 5095, F-33000 Bordeaux, France
| | | | | | - Roza Kucharczyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
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Heidari MM, Khatami M, Kamalipour A, Kalantari M, Movahed M, Emmamy MH, Hadadzadeh M, Bragança J, Namnabat M, Mazrouei B. Mitochondrial mutations in protein coding genes of respiratory chain including complexes IV, V, and mt-tRNA genes are associated risk factors for congenital heart disease. EXCLI JOURNAL 2022; 21:1306-1330. [PMID: 36483916 PMCID: PMC9727243 DOI: 10.17179/excli2022-5298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 10/31/2022] [Indexed: 01/25/2023]
Abstract
Most studies aiming at unraveling the molecular events associated with cardiac congenital heart disease (CHD) have focused on the effect of mutations occurring in the nuclear genome. In recent years, a significant role has been attributed to mitochondria for correct heart development and maturation of cardiomyocytes. Moreover, numerous heart defects have been associated with nucleotide variations occurring in the mitochondrial genome, affecting mitochondrial functions and cardiac energy metabolism, including genes encoding for subunits of respiratory chain complexes. Therefore, mutations in the mitochondrial genome may be a major cause of heart disease, including CHD, and their identification and characterization can shed light on pathological mechanisms occurring during heart development. Here, we have analyzed mitochondrial genetic variants in previously reported mutational genome hotspots and the flanking regions of mt-ND1, mt-ND2, mt-COXI, mt-COXII, mt-ATPase8, mt-ATPase6, mt-COXIII, and mt-tRNAs (Ile, Gln, Met, Trp, Ala, Asn, Cys, Tyr, Ser, Asp, and Lys) encoding genes by polymerase chain reaction-single stranded conformation polymorphism (PCR-SSCP) in 200 patients with CHD, undergoing cardiac surgery. A total of 23 mitochondrial variations (5 missense mutations, 8 synonymous variations, and 10 nucleotide changes in tRNA encoding genes) were identified and included 16 novel variants. Additionally, we showed that intracellular ATP was significantly reduced (P=0.002) in CHD patients compared with healthy controls, suggesting that the mutations have an impact on mitochondrial energy production. Functional and structural alterations caused by the mitochondrial nucleotide variations in the gene products were studied in-silico and predicted to convey a predisposing risk factor for CHD. Further studies are necessary to better understand the mechanisms by which the alterations identified in the present study contribute to the development of CHD in patients.
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Affiliation(s)
- Mohammad Mehdi Heidari
- Department of Biology, Yazd University, Yazd, Iran,*To whom correspondence should be addressed: Mohammad Mehdi Heidari, Department of Biology, Yazd University, Yazd, Iran; Tel.: +98 353 1232650, Fax: +98 353 8210644, E-mail:
| | | | | | | | | | | | - Mehdi Hadadzadeh
- Department of Cardiac Surgery, Afshar Hospital, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - José Bragança
- Faculty of Medicine and Biomedical Sciences, Algarve Biomedical Center Research Institute, University of Algarve, Faro, Portugal
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Guo L, Wang Y, Yang X, Wang T, Yin J, Zhao L, Lin Y, Dai Y, Hou S, Duan H. Aberrant mitochondrial DNA methylation and declined pulmonary function in a population with polycyclic aromatic hydrocarbon composition in particulate matter. ENVIRONMENTAL RESEARCH 2022; 214:113797. [PMID: 35779619 DOI: 10.1016/j.envres.2022.113797] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/12/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
Air pollution exposure has been found to be associated with epigenetic modification of the mitochondrial genome, which could subsequently induce adverse health outcomes. However, very limited studies exist regarding the association between fine particulate matter (PM2.5) exposure and pulmonary function at the molecular level of mitochondrial epigenetic changes. This study aimed to investigate the association of platelet mitochondrial DNA (mtDNA) methylation with occupational PM2.5 exposure and pulmonary function. First, 768 participants were occupationally exposed to polycyclic aromatic hydrocarbon (PAH)-enriched PM2.5 in a coke-oven plant in East China. The levels of PM2.5, PAH components bound to PM2.5, and urinary PAH metabolites in the workplace environment were measured as an internal dose, respectively. mtDNA methylation was measured by bisulfite pyrosequencing of two genes of ATP synthase (MT-ATP6 and MT-ATP8). Mediation analysis was conducted to evaluate the role of mtDNA methylation in pulmonary alteration induced by PAH. A decreasing trend of platelet mtDNA methylation was observed with increase in PM2.5 exposure across all participants. As an important PAH metabolite in urine, 1-hydroxypyrene (1-OHP) was significantly negatively associated with FEV1/FVC (Forced Expiratory Volume in 1s/Forced Vital Capacity) ratio. The participants with high serum folate levels (≥10 nmol/L) showed positive association between MT-ATP6 methylation and FEV1/FVC ratio. Mediation analysis suggested that MT-ATP6 methylation mediated the significant association of urinary 1-OHP with FEV1/FVC. Our findings suggested the methylation of platelet mitochondrial gene MT-ATP6 and FEV1/FVC to be negatively associated with PM exposure. Platelet mtDNA methylation acted as an intermediary between PAH exposure and lung function decline. The mitochondrial epigenetic regulation in platelets, in response to PM exposure, might be involved in subsequent progress of abnormal pulmonary function.
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Affiliation(s)
- Liqiong Guo
- Wenzhou Safety (Emergency) Institute, Tianjin University, Wenzhou, China; Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China; Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
| | - Yanhua Wang
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Xueli Yang
- Department of Occupational & Environmental Health, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Ting Wang
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Jingjing Yin
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Lei Zhao
- Wenzhou Safety (Emergency) Institute, Tianjin University, Wenzhou, China; Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China; Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
| | - Yang Lin
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Yufei Dai
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Shike Hou
- Wenzhou Safety (Emergency) Institute, Tianjin University, Wenzhou, China; Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China; Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China.
| | - Huawei Duan
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China.
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Campbell T, Slone J, Huang T. Mitochondrial Genome Variants as a Cause of Mitochondrial Cardiomyopathy. Cells 2022; 11:cells11182835. [PMID: 36139411 PMCID: PMC9496904 DOI: 10.3390/cells11182835] [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] [Received: 07/14/2022] [Revised: 09/05/2022] [Accepted: 09/07/2022] [Indexed: 11/16/2022] Open
Abstract
Mitochondria are small double-membraned organelles responsible for the generation of energy used in the body in the form of ATP. Mitochondria are unique in that they contain their own circular mitochondrial genome termed mtDNA. mtDNA codes for 37 genes, and together with the nuclear genome (nDNA), dictate mitochondrial structure and function. Not surprisingly, pathogenic variants in the mtDNA or nDNA can result in mitochondrial disease. Mitochondrial disease primarily impacts tissues with high energy demands, including the heart. Mitochondrial cardiomyopathy is characterized by the abnormal structure or function of the myocardium secondary to genetic defects in either the nDNA or mtDNA. Mitochondrial cardiomyopathy can be isolated or part of a syndromic mitochondrial disease. Common manifestations of mitochondrial cardiomyopathy are a phenocopy of hypertrophic cardiomyopathy, dilated cardiomyopathy, and cardiac conduction defects. The underlying pathophysiology of mitochondrial cardiomyopathy is complex and likely involves multiple abnormal processes in the cell, stemming from deficient oxidative phosphorylation and ATP depletion. Possible pathophysiology includes the activation of alternative metabolic pathways, the accumulation of reactive oxygen species, dysfunctional mitochondrial dynamics, abnormal calcium homeostasis, and mitochondrial iron overload. Here, we highlight the clinical assessment of mtDNA-related mitochondrial cardiomyopathy and offer a novel hypothesis of a possible integrated, multivariable pathophysiology of disease.
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Ganapathi M, Friocourt G, Gueguen N, Friederich MW, Le Gac G, Okur V, Loaëc N, Ludwig T, Ka C, Tanji K, Marcorelles P, Theodorou E, Lignelli-Dipple A, Voisset C, Walker MA, Briere LC, Bourhis A, Blondel M, LeDuc C, Hagen J, Cooper C, Muraresku C, Ferec C, Garenne A, Lelez-Soquet S, Rogers CA, Shen Y, Strode DK, Bizargity P, Iglesias A, Goldstein A, High FA, Network UD, Sweetser DA, Ganetzky R, Van Hove JLK, Procaccio V, Le Marechal C, Chung WK. A homozygous splice variant in ATP5PO, disrupts mitochondrial complex V function and causes Leigh syndrome in two unrelated families. J Inherit Metab Dis 2022; 45:996-1012. [PMID: 35621276 PMCID: PMC9474623 DOI: 10.1002/jimd.12526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 05/17/2022] [Accepted: 05/23/2022] [Indexed: 11/10/2022]
Abstract
Mitochondrial complex V plays an important role in oxidative phosphorylation by catalyzing the generation of ATP. Most complex V subunits are nuclear encoded and not yet associated with recognized Mendelian disorders. Using exome sequencing, we identified a rare homozygous splice variant (c.87+3A>G) in ATP5PO, the complex V subunit which encodes the oligomycin sensitivity conferring protein, in three individuals from two unrelated families, with clinical suspicion of a mitochondrial disorder. These individuals had a similar, severe infantile and often lethal multi-systemic disorder that included hypotonia, developmental delay, hypertrophic cardiomyopathy, progressive epileptic encephalopathy, progressive cerebral atrophy, and white matter abnormalities on brain MRI consistent with Leigh syndrome. cDNA studies showed a predominant shortened transcript with skipping of exon 2 and low levels of the normal full-length transcript. Fibroblasts from the affected individuals demonstrated decreased ATP5PO protein, defective assembly of complex V with markedly reduced amounts of peripheral stalk proteins, and complex V hydrolytic activity. Further, expression of human ATP5PO cDNA without exon 2 (hATP5PO-∆ex2) in yeast cells deleted for yATP5 (ATP5PO homolog) was unable to rescue growth on media which requires oxidative phosphorylation when compared to the wild type construct (hATP5PO-WT), indicating that exon 2 deletion leads to a non-functional protein. Collectively, our findings support the pathogenicity of the ATP5PO c.87+3A>G variant, which significantly reduces but does not eliminate complex V activity. These data along with the recent report of an affected individual with ATP5PO variants, add to the evidence that rare biallelic variants in ATP5PO result in defective complex V assembly, function and are associated with Leigh syndrome.
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Affiliation(s)
- Mythily Ganapathi
- Department of Pathology & Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
| | | | - Naig Gueguen
- MitoLab, UMR CNRS 6015 - INSERM U1083, MitoVasc Institute, Angers University Hospital, Angers, France
| | - Marisa W Friederich
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, Colorado, USA
- Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, Aurora, Colorado, USA
| | - Gerald Le Gac
- Univ Brest, Inserm, EFS, UMR1078, France
- CHRU de Brest, Service de Génétique Médicale et Biologie de la Reproduction, Laboratoire de Génétique Moléculaire et Histocompatibilité, France
| | - Volkan Okur
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| | | | - Thomas Ludwig
- Univ Brest, Inserm, EFS, UMR1078, France
- CHRU de Brest, Service de Génétique Médicale et Biologie de la Reproduction, Laboratoire de Génétique Moléculaire et Histocompatibilité, France
| | - Chandran Ka
- Univ Brest, Inserm, EFS, UMR1078, France
- CHRU de Brest, Service de Génétique Médicale et Biologie de la Reproduction, Laboratoire de Génétique Moléculaire et Histocompatibilité, France
| | - Kurenai Tanji
- Department of Pathology & Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
| | - Pascale Marcorelles
- CHRU de Brest, Service d'anatomie cytologie pathologie, CHU et centre de référence des maladies neuromusculaires, Brest, France
| | - Evangelos Theodorou
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Division of Medical Genetics & Metabolism, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Angela Lignelli-Dipple
- Department of Radiology, Columbia University Irving Medical Center, New York, New York, USA
| | | | - Melissa A Walker
- Division of Neurogenetics, Child Neurology, Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Lauren C Briere
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Amélie Bourhis
- CHRU de Brest, Service d'anatomie cytologie pathologie, CHU et centre de référence des maladies neuromusculaires, Brest, France
| | | | - Charles LeDuc
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| | - Jacob Hagen
- Department of Biomedical Sciences, Columbia University Irving Medical Center, New York, New York, USA
| | - Cathleen Cooper
- Department of Radiology, Columbia University Irving Medical Center, New York, New York, USA
| | - Colleen Muraresku
- Department of Pediatrics, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
- Mitochondrial Medicine Frontier Program, Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | | | | | | | - Cassandra A Rogers
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Yufeng Shen
- Department of Biomedical Sciences, Columbia University Irving Medical Center, New York, New York, USA
| | - Dana K Strode
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, Colorado, USA
| | - Peyman Bizargity
- Division of Medical Genetics, Cohen Children's Medical Center, New York, New York, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, New York, New York, USA
| | - Alejandro Iglesias
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
| | - Amy Goldstein
- Department of Pediatrics, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
- Mitochondrial Medicine Frontier Program, Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Frances A High
- Division of Medical Genetics & Metabolism, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, USA
| | | | - David A Sweetser
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Division of Medical Genetics & Metabolism, Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Rebecca Ganetzky
- Department of Pediatrics, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
- Mitochondrial Medicine Frontier Program, Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Johan L K Van Hove
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, Colorado, USA
- Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, Aurora, Colorado, USA
| | - Vincent Procaccio
- MitoLab, UMR CNRS 6015 - INSERM U1083, MitoVasc Institute, Angers University Hospital, Angers, France
| | - Cedric Le Marechal
- Univ Brest, Inserm, EFS, UMR1078, France
- CHRU de Brest, Service de Génétique Médicale et Biologie de la Reproduction, Laboratoire de Génétique Moléculaire et Histocompatibilité, France
| | - Wendy K Chung
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York, USA
- Department of Medicine, Columbia University Irving Medical Center, New York, New York, USA
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Lin HY, Yang YN, Chen YF, Huang TY, Crawford DR, Chuang HY, Chin YT, Chu HR, Li ZL, Shih YJ, Chen YR, Yang YCSH, Ho Y, Davis PJ, Whang-Peng J, Wang K. 2,3,5,4′-Tetrahydroxystilbene-2-O-β-D-Glucoside improves female ovarian aging. Front Cell Dev Biol 2022; 10:862045. [PMID: 36111333 PMCID: PMC9469098 DOI: 10.3389/fcell.2022.862045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 08/02/2022] [Indexed: 11/18/2022] Open
Abstract
Reduced fertility associated with normal aging may reflect the over-maturity of oocytes. It is increasingly important to reduce aging-induced infertility since recent trends show people marrying at later ages. 2,3,5,4′-Tetrahydroxystilbene-2-O-β-D-glucoside (THSG), a polyphenol extracted from Polygonum multiflorum, has been reported to have anti-inflammatory and anti-aging properties. To evaluate whether THSG can reduce aging-related ovarian damage in a female mouse model of aging, THSG was administered by gavage at a dose of 10 mg/kg twice weekly, starting at 4 weeks of age in a group of young mice. In addition, the effect of THSG in a group of aged mice was also studied in mice starting at 24 weeks of age. The number of oocytes in the THSG-fed group was higher than in the untreated control group. Although the percentage of secondary polar bodies (PB2) decreased during aging in the THSG-fed group, it decreased much more slowly than in the age-matched control group. THSG administration increased the quality of ovaries in young mice becoming aged. Western blotting analyses also indicated that CYP19, PR-B, and ER-β expressions were significantly increased in 36-week-old mice. THSG also increased oocyte numbers in aged mice compared to mice without THSG fed. Studies of qPCR and immunohistochemistry (IHC) analyses of ovaries in the aged mice groups were conducted. THSG increased gene expression of anti-Müllerian hormone (AMH), a biomarker of oocyte number, and protein accumulation in 40-week-old mice. THSG increased the expression of pgc1α and atp6, mitochondrial biogenesis-related genes, and their protein expression. THSG also attenuated the fading rate of CYP11a and CYP19 associated with sex hormone synthesis. And THSG maintains a high level of ER-β expression, thereby enhancing the sensitivity of estrogen. Our findings indicated that THSG increased or extended gene expression involved in ovarian maintenance and rejuvenation in young and aged mice. On the other hand, THSG treatments significantly maintained oocyte quantity and quality in both groups of young and aged mice compared to each age-matched control group. In conclusion, THSG can delay aging-related menopause, and the antioxidant properties of THSG may make it suitable for preventing aging-induced infertility.
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Affiliation(s)
- Hung-Yun Lin
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- TMU Research Center of Cancer Translational Medicine, Taipei Medical University, Taipei, Taiwan
- Traditional Herbal Medicine Research Center of Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan
- Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, Albany, NY, United States
- Cancer Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Yung-Ning Yang
- School of Medicine, I-Shou University, Kaohsiung, Taiwan
- Department of Pediatrics, E-DA Hospital, Kaohsiung, Taiwan
| | - Yi-Fong Chen
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Tung-Yung Huang
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Dana R. Crawford
- Department of Immunology and Microbial Disease, Albany Medical College, Albany, NY, United States
| | - Hui-Yu Chuang
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Department of Obstetrics and Gynecology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Yu-Tang Chin
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
| | - Hung-Ru Chu
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Graduate Institute of Nanomedicine and Medical Engineering, College of Medical Engineering, Taipei Medical University, Taipei, Taiwan
| | - Zi-Lin Li
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Graduate Institute of Nanomedicine and Medical Engineering, College of Medical Engineering, Taipei Medical University, Taipei, Taiwan
| | - Ya-Jung Shih
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Graduate Institute of Nanomedicine and Medical Engineering, College of Medical Engineering, Taipei Medical University, Taipei, Taiwan
| | - Yi-Ru Chen
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Graduate Institute of Nanomedicine and Medical Engineering, College of Medical Engineering, Taipei Medical University, Taipei, Taiwan
| | - Yu-Chen S. H. Yang
- Joint Biobank, Office of Human Research, Taipei Medical University, Taipei, Taiwan
| | - Yih Ho
- School of Pharmacy, Taipei Medical University, Taipei, Taiwan
- *Correspondence: Yih Ho,
| | - Paul J. Davis
- Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, Albany, NY, United States
- Department of Medicine, Albany Medical College, Albany, NY, United States
| | - Jacqueline Whang-Peng
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Cancer Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Kuan Wang
- Graduate Institute of Nanomedicine and Medical Engineering, College of Medical Engineering, Taipei Medical University, Taipei, Taiwan
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van de Loo KFE, van Zeijl NT, Custers JAE, Janssen MCH, Verhaak CM. A conceptual disease model for quality of life in mitochondrial disease. Orphanet J Rare Dis 2022; 17:263. [PMID: 35841006 PMCID: PMC9287990 DOI: 10.1186/s13023-022-02411-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 06/26/2022] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Previous studies in patients with a mitochondrial disease (MD) highlight the high prevalence of cognitive impairments, fatigue, depression, and a lower quality of life (QoL). The relationship with biological and physiological factors remains complex. The aim of this study is to investigate the status of and interrelationships between biological and physiological functioning, cognitive functioning as well as fatigue, depression, societal participation, health perceptions, and QoL, by using the Wilson and Cleary conceptual disease model, adapted to MD. METHODS Patients with a genetically confirmed MD were included. The following health concepts in MD were investigated according to the conceptual model: (1) Biological and physiological: disease manifestation (Newcastle Mitochondrial Disease Adult Scale), (2) Symptom status: cognitive functioning, patient reported fatigue and depressive symptoms, (3) Functional health: societal participation, (4) Patient reported health perceptions, and (5) Overall QoL. Data were compared to healthy normative data and/or data from other patient groups. Correlations as well as a hierarchical regression analysis were performed to assess the relations between the different levels of health concepts in the conceptual model. RESULTS Of the 95 included patients, 42% had a severe disease manifestation. Comparable or worse than normative data and other patient groups, 35% reported cognitive impairments, 80% severe fatigue, and 27% depressive symptoms. Patients experienced impairments in societal participation and QoL. Disease manifestation was significantly correlated with cognitive functioning, societal participation, physical functioning and overall QoL, but not with fatigue or depressive symptoms. Almost all outcome measures regarding functional health, health perceptions and QoL were correlated with symptom status variables. Overall QoL was significantly predicted by fatigue and physical functioning. CONCLUSIONS Symptom status is related to the functional health, health perceptions and QoL in patients with MD. Moreover, fatigue and physical functioning are important contributors to the overall QoL of MD patients. In order to provide adequate patient care it is important to have a broad view on patients' functioning, not only by providing a proper clinical assessment, but also to screen for symptom status; cognitive functioning, fatigue and depression.
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Affiliation(s)
- Kim F E van de Loo
- Department of Medical Psychology, Radboud Center for Mitochondrial Medicine, Amalia Children's Hospital, Radboud Institute for Health Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 10, PO Box 9101, 6500 HB, Nijmegen, The Netherlands.
| | - Nander T van Zeijl
- Department of Internal Medicine, Radboud Center for Mitochondrial Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 10, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - José A E Custers
- Department of Medical Psychology, Radboud Center for Mitochondrial Medicine, Amalia Children's Hospital, Radboud Institute for Health Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 10, PO Box 9101, 6500 HB, Nijmegen, The Netherlands.
| | - Mirian C H Janssen
- Department of Internal Medicine, Radboud Center for Mitochondrial Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 10, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Christianne M Verhaak
- Department of Medical Psychology, Radboud Center for Mitochondrial Medicine, Amalia Children's Hospital, Radboud Institute for Health Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 10, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
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Jiang P, Zhu T, Liu J, Tao X, Xue Z, Tao Y, Chen H, Zeng X, Zhu W, Shu Q, Yu L. Mitochondrial DNA variants spectrum and the association with chronic Tic disorders. Eur J Neurol 2022; 29:3187-3196. [PMID: 35781907 DOI: 10.1111/ene.15484] [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: 01/25/2022] [Revised: 05/05/2022] [Accepted: 06/30/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND Tic disorders (TD) are childhood-onset neuropsychiatric disorders characterized by single or multiple sudden, rapid, recurrent, and motor tics and/or vocal tics. Several nuclear genes that involved in mitochondrial functions suggest potential role of mitochondria in tic deficit. METHODS To evaluate the association of mitochondrial DNA (mtDNA) variants with Tic disorders, we screened the whole mitochondrial genomes in 493 TD patients and 109 age- and sex matched healthy controls using next-generation sequencing technology. RESULTS A total of 1918 mtDNA variants including 1220 variants in patients only, 154 variants in controls only, and 544 variants shared by both cases and controls were identified. We found higher number of overall mtDNA variants in TD patients (P =0.00028). The variant density in MT-ATP6/8 and MT-CYB coding regions had significant difference between TD patients and controls (P=0.0025 and P=0.003, respectively). Furthermore, we observed a significant association of 15 common variants with TD based on additive model, including m.14766C>T, m.14783T>C, m.14905G>A, and m.15301G>A in MT-CYB; m.4769A>G, m.10398A>G, m.12705C>T, and m.12850A>G in MT-ND genes; m.7028C>T in MT-CO1; m.8701A>G in MT-ATP6; two noncoding variants with m.16223C>T, m.5580T>C; and three rRNA variants with m.1438A>G and m.750A>G in RNR1, and m.2352T>C in RNR2. CONCLUSIONS Our data provide the evidence of mtDNA variants associated with tic disorders. The accumulation of the heteroplasmic levels may increase the risk of TD. Replication studies with larger samples are necessary to understand the pathogenesis of TD.
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Affiliation(s)
- Peifang Jiang
- Department of Neurology at The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Tao Zhu
- Department of Critical Care Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jiajing Liu
- Department of Neurology at The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Xiaohan Tao
- Department of Neurology at The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Ziru Xue
- Department of Neurology at The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Yiling Tao
- Department of Neurology at The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Hongyu Chen
- The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Xiaojing Zeng
- The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Weiyi Zhu
- School of Mental Health, Wenzhou Medical University, Wenzhou, China
| | - Qiang Shu
- The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Lan Yu
- The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
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Phenotype-Genotype Analysis Based on Molecular Classification in 135 Children With Mitochondrial Disease. Pediatr Neurol 2022; 132:11-18. [PMID: 35598585 DOI: 10.1016/j.pediatrneurol.2022.04.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 03/29/2022] [Accepted: 04/25/2022] [Indexed: 11/20/2022]
Abstract
OBJECTIVES Over the past decades, mitochondrial disease classification has been mainly based on molecular defects. We aim to analyze phenotype-genotype correlation of mitochondrial disorders according to molecular classification. METHODS In this cohort study, we identified 135 individuals diagnosed with mitochondrial disorders, and all patients were divided into four subgroups based on molecular functions: the Respiratory Chain group (including subunits and assembly proteins in the respiratory chain), the Protein Synthesis group (including mitochondrial RNA metabolism, mitochondrial translation), the mitcohindrial DNA (mtDNA) Replication group, and the Others group (including cofactors, homeostasis, substrates, and inhibitors). RESULTS We found that in China, patients with the mtDNA variant constituted a large percentage of mitochondrial disease and were associated with a male preponderance in the Respiratory Chain group, whereas those in the Protein Synthesis group showed a relatively later onset and higher serum lactate level. In contrast, patients with nuclear DNA variants were younger at onset, with no specific lactate or cranial imaging features, especially in the Others group, which contained several mitochondrial diseases with corresponding treatment. CONCLUSION The mtDNA was recommended to detect first in patients with typical lactate and cranial imaging features. A broader consideration and detection are necessary for a better prognosis in an atypical patient.
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Lorenz C, Zink A, Henke MT, Staege S, Mlody B, Bünning M, Wanker E, Diecke S, Schuelke M, Prigione A. Generation of four iPSC lines from four patients with Leigh syndrome carrying homoplasmic mutations m.8993T > G or m.8993T > C in the mitochondrial gene MT-ATP6. Stem Cell Res 2022; 61:102742. [DOI: 10.1016/j.scr.2022.102742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 03/03/2022] [Accepted: 03/04/2022] [Indexed: 10/18/2022] Open
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Lange LM, Gonzalez-Latapi P, Rajalingam R, Tijssen MAJ, Ebrahimi-Fakhari D, Gabbert C, Ganos C, Ghosh R, Kumar KR, Lang AE, Rossi M, van der Veen S, van de Warrenburg B, Warner T, Lohmann K, Klein C, Marras C. Nomenclature of Genetic Movement Disorders: Recommendations of the International Parkinson and Movement Disorder Society Task Force - An Update. Mov Disord 2022; 37:905-935. [PMID: 35481685 DOI: 10.1002/mds.28982] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/28/2022] [Accepted: 02/14/2022] [Indexed: 12/13/2022] Open
Abstract
In 2016, the Movement Disorder Society Task Force for the Nomenclature of Genetic Movement Disorders presented a new system for naming genetically determined movement disorders and provided a criterion-based list of confirmed monogenic movement disorders. Since then, a substantial number of novel disease-causing genes have been described, which warrant classification using this system. In addition, with this update, we further refined the system and propose dissolving the imaging-based categories of Primary Familial Brain Calcification and Neurodegeneration with Brain Iron Accumulation and reclassifying these genetic conditions according to their predominant phenotype. We also introduce the novel category of Mixed Movement Disorders (MxMD), which includes conditions linked to multiple equally prominent movement disorder phenotypes. In this article, we present updated lists of newly confirmed monogenic causes of movement disorders. We found a total of 89 different newly identified genes that warrant a prefix based on our criteria; 6 genes for parkinsonism, 21 for dystonia, 38 for dominant and recessive ataxia, 5 for chorea, 7 for myoclonus, 13 for spastic paraplegia, 3 for paroxysmal movement disorders, and 6 for mixed movement disorder phenotypes; 10 genes were linked to combined phenotypes and have been assigned two new prefixes. The updated lists represent a resource for clinicians and researchers alike and they have also been published on the website of the Task Force for the Nomenclature of Genetic Movement Disorders on the homepage of the International Parkinson and Movement Disorder Society (https://www.movementdisorders.org/MDS/About/Committees--Other-Groups/MDS-Task-Forces/Task-Force-on-Nomenclature-in-Movement-Disorders.htm). © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.
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Affiliation(s)
- Lara M Lange
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Paulina Gonzalez-Latapi
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada.,Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Rajasumi Rajalingam
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
| | - Marina A J Tijssen
- UMCG Expertise Centre Movement Disorders, Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Darius Ebrahimi-Fakhari
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Carolin Gabbert
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christos Ganos
- Department of Neurology, Charité University Hospital Berlin, Berlin, Germany
| | - Rhia Ghosh
- Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Kishore R Kumar
- Molecular Medicine Laboratory and Department of Neurology, Concord Repatriation General Hospital, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.,Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Anthony E Lang
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
| | - Malco Rossi
- Movement Disorders Section, Neuroscience Department, Raul Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina
| | - Sterre van der Veen
- UMCG Expertise Centre Movement Disorders, Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Bart van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Center of Expertise for Parkinson and Movement Disorders, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Tom Warner
- Department of Clinical & Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Katja Lohmann
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Connie Marras
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
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Kuan SW, Chua KH, Tan EW, Tan LK, Loch A, Kee BP. Whole mitochondrial genome sequencing of Malaysian patients with cardiomyopathy. PeerJ 2022; 10:e13265. [PMID: 35441061 PMCID: PMC9013480 DOI: 10.7717/peerj.13265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 03/23/2022] [Indexed: 01/13/2023] Open
Abstract
Cardiomyopathy (CMP) constitutes a diverse group of myocardium diseases affecting the pumping ability of the heart. Genetic predisposition is among the major factors affecting the development of CMP. Globally, there are over 100 genes in autosomal and mitochondrial DNA (mtDNA) that have been reported to be associated with the pathogenesis of CMP. However, most of the genetic studies have been conducted in Western countries, with limited data being available for the Asian population. Therefore, this study aims to investigate the mutation spectrum in the mitochondrial genome of 145 CMP patients in Malaysia. Long-range PCR was employed to amplify the entire mtDNA, and whole mitochondrial genome sequencing was conducted on the MiSeq platform. Raw data was quality checked, mapped, and aligned to the revised Cambridge Reference Sequence (rCRS). Variants were named, annotated, and filtered. The sequencing revealed 1,077 variants, including 18 novel and 17 CMP and/or mitochondrial disease-associated variants after filtering. In-silico predictions suggested that three of the novel variants (m.8573G>C, m.11916T>A and m.11918T>G) in this study are potentially pathogenic. Two confirmed pathogenic variants (m.1555A>G and m.11778G>A) were also found in the CMP patients. The findings of this study shed light on the distribution of mitochondrial mutations in Malaysian CMP patients. Further functional studies are required to elucidate the role of these variants in the development of CMP.
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Affiliation(s)
- Sheh Wen Kuan
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - E-Wei Tan
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Lay Koon Tan
- National Heart Institute, Kuala Lumpur, Malaysia
| | - Alexander Loch
- Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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40
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Na J, Lee Y. Genotype-phenotype analysis of MT-ATP6-associated Leigh syndrome. Acta Neurol Scand 2022; 145:414-422. [PMID: 34877647 DOI: 10.1111/ane.13566] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 11/25/2021] [Accepted: 11/27/2021] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Mitochondrial DNA (mtDNA)-associated Leigh syndrome (LS) is characterized by maternal inheritance, and the heteroplasmic mutant load of mtDNA pathogenic variants is known to affect clinical phenotypes. Among mtDNA pathogenic variants, variants of the MT-ATP6 gene account for most of reported cases. In this report, we aimed to describe the clinical and genetic findings of MT-ATP6-associated LS patients diagnosed at a single tertiary institution in Korea. METHODS Thirteen patients with genetically confirmed MT-ATP6-associated LS were selected. We reviewed each patient's clinical findings, including general characteristics, biochemical parameters, brain MR images, muscle biopsy results, and heteroplasmic mutant load over a long-term follow-up period. RESULTS MT-ATP6-associated LS was of predominantly early onset (age <2 years), although we identified 2 late-onset (>60 months) LS patients. The heteroplasmic mutant load estimated by next-generation sequencing was 96%-100% in all nucleotide change groups. Compared with other forms of MT-ATP6-associated LS, the m.8993T>G point mutation elicited a significantly higher rate of symptom onset before 2 years of age. Brain MRI showed bilateral basal ganglia involvement in all patients, followed by cerebral atrophy, brainstem and thalamus involvement, and cerebellar atrophy. After follow-up (median 7.2 years, range 1.4 to 11.5 years), LS with m.8993T>G point mutations had a slightly more severe clinical progression compared with other forms of MT-ATP6-associated LS. CONCLUSIONS MT-ATP6-associated LS patients presented with a broad spectrum of clinical diagnoses and had a very high heteroplasmic mutant load. This study provides valuable data on MT-ATP6-associated LS that will inform subsequent studies on LS.
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Affiliation(s)
- Ji‐Hoon Na
- Department of Pediatrics Yonsei University College of Medicine Seoul Korea
| | - Young‐Mock Lee
- Department of Pediatrics Yonsei University College of Medicine Seoul Korea
- Epilepsy Research Institute Yonsei University College of Medicine Seoul Korea
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The Mitochondrial Genome in Aging and Disease and the Future of Mitochondrial Therapeutics. Biomedicines 2022; 10:biomedicines10020490. [PMID: 35203698 PMCID: PMC8962324 DOI: 10.3390/biomedicines10020490] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 02/10/2022] [Accepted: 02/16/2022] [Indexed: 11/29/2022] Open
Abstract
Mitochondria are intracellular organelles that utilize nutrients to generate energy in the form of ATP by oxidative phosphorylation. Mitochondrial DNA (mtDNA) in humans is a 16,569 base pair double-stranded circular DNA that encodes for 13 vital proteins of the electron transport chain. Our understanding of the mitochondrial genome’s transcription, translation, and maintenance is still emerging, and human pathologies caused by mtDNA dysfunction are widely observed. Additionally, a correlation between declining mitochondrial DNA quality and copy number with organelle dysfunction in aging is well-documented in the literature. Despite tremendous advancements in nuclear gene-editing technologies and their value in translational avenues, our ability to edit mitochondrial DNA is still limited. In this review, we discuss the current therapeutic landscape in addressing the various pathologies that result from mtDNA mutations. We further evaluate existing gene therapy efforts, particularly allotopic expression and its potential to become an indispensable tool for restoring mitochondrial health in disease and aging.
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Stenton SL, Zou Y, Cheng H, Liu Z, Wang J, Shen D, Jin H, Ding C, Tang X, Sun S, Han H, Ma Y, Zhang W, Jin R, Wang H, Sun D, Lv JL, Prokisch H, Fang F. Leigh syndrome: a study of 209 patients at the Beijing Children's Hospital. Ann Neurol 2022; 91:466-482. [PMID: 35094435 DOI: 10.1002/ana.26313] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 01/25/2022] [Accepted: 01/27/2022] [Indexed: 11/12/2022]
Affiliation(s)
- Sarah L. Stenton
- Institute of Human Genetics, School of Medicine Technical University of Munich Munich Germany
- Institute of Neurogenomics Helmholtz Zentrum München Neuherberg Germany
| | - Ying Zou
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
| | - Hua Cheng
- Image Center, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
| | - Zhimei Liu
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
| | - Junling Wang
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
| | - Danmin Shen
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
| | - Hong Jin
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
| | - Changhong Ding
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
| | - Xiaolu Tang
- Image Center, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
| | - Suzhen Sun
- Department of Neurology Children's Hospital of Hebei Province Shijiazhuang China
| | - Hong Han
- Department of Neurology Children's Hospital of Shanxi Province Taiyuan China
| | - Yanli Ma
- Department of Neurology Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital Zhengzhou China
| | - Weihua Zhang
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
- Department of Neurology Children's Hospital Affiliated to Zhengzhou University, Henan Children's Hospital Zhengzhou China
| | - Ruifeng Jin
- Department of Neurology Qilu Children's Hospital of Shandong University Jinan China
| | - Hua Wang
- Department of Pediatrics Shengjing Hospital of China Medical University Shenyang China
| | - Dan Sun
- Department of Neurology Wuhan Children's Hospital Wuhan China
| | - Jun Lan Lv
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
| | - Holger Prokisch
- Institute of Human Genetics, School of Medicine Technical University of Munich Munich Germany
- Institute of Neurogenomics Helmholtz Zentrum München Neuherberg Germany
| | - Fang Fang
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital Capital Medical University Beijing China
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Clinical Heterogeneity in MT-ATP6 Pathogenic Variants: Same Genotype-Different Onset. Cells 2022; 11:cells11030489. [PMID: 35159298 PMCID: PMC8834419 DOI: 10.3390/cells11030489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 01/22/2022] [Accepted: 01/26/2022] [Indexed: 12/12/2022] Open
Abstract
Human mitochondrial disease exhibits large variation of clinical phenotypes, even in patients with the same causative gene defect. We illustrate this heterogeneity by confronting clinical and biochemical data of two patients with the uncommon pathogenic homoplasmic NC_012920.1(MT-ATP6):m.9035T>C variant in MT-ATP6. Patient 1 presented as a toddler with severe motor and speech delay and spastic ataxia without extra-neurologic involvement. Patient 2 presented in adolescence with ataxia and ophthalmoplegia without cognitive or motor impairment. Respiratory chain complex activities were normal in cultured skin fibroblasts from both patients when calculated as ratios over citrate synthase activity. Native gels found presence of subcomplexes of complex V in fibroblast and/or skeletal muscle. Bioenergetic measurements in fibroblasts from both patients detected reduced spare respiratory capacities and altered extracellular acidification rates, revealing a switch from mitochondrial respiration to glycolysis to uphold ATP production. Thus, in contrast to the differing disease presentation, biochemical evidence of mitochondrial deficiency turned out quite similar. We conclude that biochemical analysis remains a valuable tool to confirm the genetic diagnosis of mitochondrial disease, especially in patients with new gene variants or atypical clinical presentation.
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Molecular Genetics Overview of Primary Mitochondrial Myopathies. J Clin Med 2022; 11:jcm11030632. [PMID: 35160083 PMCID: PMC8836969 DOI: 10.3390/jcm11030632] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/13/2022] [Accepted: 01/20/2022] [Indexed: 12/29/2022] Open
Abstract
Mitochondrial disorders are the most common inherited conditions, characterized by defects in oxidative phosphorylation and caused by mutations in nuclear or mitochondrial genes. Due to its high energy request, skeletal muscle is typically involved. According to the International Workshop of Experts in Mitochondrial Diseases held in Rome in 2016, the term Primary Mitochondrial Myopathy (PMM) should refer to those mitochondrial disorders affecting principally, but not exclusively, the skeletal muscle. The clinical presentation may include general isolated myopathy with muscle weakness, exercise intolerance, chronic ophthalmoplegia/ophthalmoparesis (cPEO) and eyelids ptosis, or multisystem conditions where there is a coexistence with extramuscular signs and symptoms. In recent years, new therapeutic targets have been identified leading to the launch of some promising clinical trials that have mainly focused on treating muscle symptoms and that require populations with defined genotype. Advantages in next-generation sequencing techniques have substantially improved diagnosis. So far, an increasing number of mutations have been identified as responsible for mitochondrial disorders. In this review, we focused on the principal molecular genetic alterations in PMM. Accordingly, we carried out a comprehensive review of the literature and briefly discussed the possible approaches which could guide the clinician to a genetic diagnosis.
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Na JH, Lee MJ, Lee CH, Lee YM. Association Between Epilepsy and Leigh Syndrome With MT-ND3 Mutation, Particularly the m.10191T>C Point Mutation. Front Neurol 2021; 12:752467. [PMID: 34956047 PMCID: PMC8702430 DOI: 10.3389/fneur.2021.752467] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 11/12/2021] [Indexed: 12/12/2022] Open
Abstract
Background and Purpose: Recent advances in molecular genetic testing have led to a rapid increase in the understanding of the genetics of Leigh syndrome. Several studies have suggested that Leigh syndrome with MT-ND3 mutation is strongly associated with epilepsy. This study focused on the epilepsy-related characteristics of Leigh syndrome with MT-ND3 mutation identified in a single tertiary hospital in South Korea. Methods: We selected 31 patients with mitochondrial DNA (mtDNA) mutations who were genetically diagnosed with mtDNA-associated Leigh syndrome. Among them, seven patients with MT-ND3 mutations were detected. We reviewed various clinical findings such as laboratory findings, brain images, electroencephalography data, seizure types, seizure frequency, antiepileptic drug use history, and current seizure status. Results: The nucleotide changes in the seven patients with the Leigh syndrome with MT-ND3 mutation were divided into two groups: m.10191T>C and m.10158T>C. Six of the seven patients were found to have the m.10191T>C mutations. The median value of the mutant load was 82.5%, ranging from 57.9 to 93.6%. No particular tendency was observed for the first symptom or seizure onset or mutant load. The six patients with the m.10191T>C mutation were diagnosed with epilepsy. Three of these patients were diagnosed with Lennox-Gastaut syndrome (LGS). Conclusion: We reported a very strong association between epilepsy and MT-ND3 mutation in Leigh syndrome, particularly the m.10191T>C mutation. The possibility of an association between the epilepsy phenotype of the m.10191T>C mutation and LGS was noted.
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Affiliation(s)
- Ji-Hoon Na
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea
| | - Min Jung Lee
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea
| | - Chul Ho Lee
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea
| | - Young-Mock Lee
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea.,Epilepsy Research Institute, Yonsei University College of Medicine, Seoul, South Korea
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46
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Jurkute N, D'Esposito F, Robson AG, Pitceathly RDS, Cordeiro F, Raymond FL, Moore AT, Michaelides M, Yu-Wai-Man P, Webster AR, Arno G. SSBP1-Disease Update: Expanding the Genetic and Clinical Spectrum, Reporting Variable Penetrance and Confirming Recessive Inheritance. Invest Ophthalmol Vis Sci 2021; 62:12. [PMID: 34905022 PMCID: PMC8684315 DOI: 10.1167/iovs.62.15.12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 11/19/2021] [Indexed: 11/24/2022] Open
Abstract
Purpose To report novel genotypes and expand the phenotype spectrum of SSBP1-disease and explore potential disease mechanism. Methods Five families with previously unsolved optic atrophy and retinal dystrophy underwent whole genome sequencing as part of the National Institute for Health Research BioResource Rare-Diseases and the UK's 100,000 Genomes Project. In silico analysis and protein modelling was performed on the identified variants. Deep phenotyping including retinal imaging and International Society for Clinical Electrophysiology of Vision standard visual electrophysiology was performed. Results Seven individuals from five unrelated families with bilateral optic atrophy and/or retinal dystrophy with extraocular signs and symptoms in some are described. In total, 6 SSBP1 variants were identified including the previously unreported variants: c.151A>G, p.(Lys51Glu), c.335G>A p.(Gly112Glu), and c.380G>A, p.(Arg127Gln). One individual was found to carry biallelic variants (c.380G>A p.(Arg127Gln); c.394A>G p.(Ile132Val)) associated with likely autosomal recessive SSBP1-disease. In silico analysis predicted all variants to be pathogenic and Three-dimensional protein modelling suggested possible disease mechanisms via decreased single-stranded DNA binding affinity or impaired higher structure formation. Conclusions SSBP1 is essential for mitochondrial DNA replication and maintenance, with defects leading to a spectrum of disease that includes optic atrophy and/or retinal dystrophy, occurring with or without extraocular features. This study provides evidence of intrafamilial variability and confirms the existence of an autosomal recessive inheritance in SSBP1-disease consequent upon a previously unreported genotype.
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Affiliation(s)
- Neringa Jurkute
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
- Institute of Ophthalmology, University College London, London, United Kingdom
| | - Fabiana D'Esposito
- Imperial College Ophthalmic Research Unit, Western Eye Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom
- Eye Clinic, Department of Neurosciences, Reproductive Sciences and Dentistry, Federico II University, Naples, Italy
| | - Anthony G. Robson
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
- Institute of Ophthalmology, University College London, London, United Kingdom
| | - Robert D. S. Pitceathly
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology and The National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Francesca Cordeiro
- Imperial College Ophthalmic Research Unit, Western Eye Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom
| | - F. Lucy Raymond
- NIHR BioResource - Rare Diseases, Cambridge University Hospitals NHS Foundation Trust, Cambridge Biomedical Campus, Cambridge, United Kingdom
- Department of Medical Genetics, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Anthony T. Moore
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
- Institute of Ophthalmology, University College London, London, United Kingdom
- Department of Ophthalmology, University of California, San Francisco, San Francisco, California, United States
| | - Michel Michaelides
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
- Institute of Ophthalmology, University College London, London, United Kingdom
| | - Patrick Yu-Wai-Man
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
- Institute of Ophthalmology, University College London, London, United Kingdom
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, United Kingdom
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
| | - Andrew R. Webster
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
- Institute of Ophthalmology, University College London, London, United Kingdom
| | - Gavin Arno
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
- Institute of Ophthalmology, University College London, London, United Kingdom
- North Thames Genomic Laboratory Hub, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - for the Genomics England Research Consortium
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
- Institute of Ophthalmology, University College London, London, United Kingdom
- Imperial College Ophthalmic Research Unit, Western Eye Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom
- Eye Clinic, Department of Neurosciences, Reproductive Sciences and Dentistry, Federico II University, Naples, Italy
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology and The National Hospital for Neurology and Neurosurgery, London, United Kingdom
- NIHR BioResource - Rare Diseases, Cambridge University Hospitals NHS Foundation Trust, Cambridge Biomedical Campus, Cambridge, United Kingdom
- Department of Medical Genetics, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
- Department of Ophthalmology, University of California, San Francisco, San Francisco, California, United States
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, United Kingdom
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
- North Thames Genomic Laboratory Hub, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
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Shi Y, Chen G, Sun D, Hu C, Liu Z, Shen D, Wang J, Song T, Zhang W, Li J, Ren X, Han T, Ding C, Wang Y, Fang F. Phenotypes and genotypes of mitochondrial diseases with mtDNA variations in Chinese children: A multi-center study. Mitochondrion 2021; 62:139-150. [PMID: 34800692 DOI: 10.1016/j.mito.2021.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 10/29/2021] [Accepted: 11/12/2021] [Indexed: 11/24/2022]
Abstract
Mitochondrial DNA (mtDNA) associated mitochondrial diseases hold a crucial position but comprehensive and systematic studies are relatively rare. Among the 262 patients of four children's hospitals in China, 96%-point mutations (30 alleles in 11 genes encoding tRNA, rRNA, Complex I and V) and 4%-deletions (seven of ten had not been reported before) were identified as the cause of 14 phenotypes. MILS presented the highest genetic heterogeneity, while the m.3243A > G mutation was the only "hotspot" mutation with a wide range of phenotypes. The degrees of heteroplasmy in the leukocytes of MM were higher than MELAS. The heteroplasmy level of patients was higher than that in mild and carrier group, while we found low-level heteroplasmy pathogenic mutations as well. Some homoplasmic variations (e.g., m.9176 T > C mutation) are having high incomplete penetrance. For a suspected MELAS, m.3243A > G mutation was recommended to detect first; while for a suspected LS, trios-WES and mtDNA genome sequencing by NGS were recommended first in both blood and urine.
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Affiliation(s)
- Yuqing Shi
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Guohong Chen
- Department of Neurology, Zhengzhou University Affiliated Children's Hospital (Zhengzhou Children's Hospital), Zhengzhou 450053, Henan, China
| | - Dan Sun
- Department of Neurology, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430015, China
| | - Chaoping Hu
- Department of Neurology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Zhimei Liu
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Danmin Shen
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Junling Wang
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Tianyu Song
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Weihua Zhang
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Jiuwei Li
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Xiaotun Ren
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Tongli Han
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Changhong Ding
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Yi Wang
- Department of Neurology, Children's Hospital of Fudan University, Shanghai 201102, China.
| | - Fang Fang
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China.
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48
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T M T, N T T T, P C C. Reply to letter to the editor. Radiol Case Rep 2021; 16:4001-4002. [PMID: 34765053 PMCID: PMC8569382 DOI: 10.1016/j.radcr.2021.08.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 08/11/2021] [Indexed: 11/24/2022] Open
Affiliation(s)
- Trang T M
- Department of Neurology, University Medical Center, Ho Chi Minh City 700000, Vietnam
| | - Truc N T T
- Department of Neurology, Hospital 30-4, Ho Chi Minh City 700000, Vietnam.,Translational Medicine Division, Graduate Institute of Biomedical Informatics, Taipei Medical University, No 250 Wuxing Street, Xinyi District, Taipei, Taiwan 110
| | - Chien P C
- Department of Radiology, University Medical Center, Ho Chi Minh City 700000, Vietnam
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49
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Abstract
The term SCA refers to a phenotypically and genetically heterogeneous group of autosomal dominant spinocerebellar ataxias. Phenotypically they present as gait ataxia frequently in combination with dysarthria and oculomotor problems. Additional signs and symptoms are common and can include various pyramidal and extrapyramidal signs and intellectual impairment. Genetic causes of SCAs are either repeat expansions within disease genes or common mutations (point mutations, deletions, insertions etc.). Frequently the two types of mutations cause indistinguishable phenotypes (locus heterogeneity). This article focuses on SCAs caused by common mutations. It describes phenotype and genotype of the presently 27 types known and discusses the molecular pathogenesis in those 21 types where the disease gene has been identified. Apart from the dominant types, the article also summarizes findings in a variant caused by mutations in a mitochondrial gene. Possible common disease mechanisms are considered based on findings in the various SCAs described.
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Affiliation(s)
- Ulrich Müller
- Institute of Human Genetics, JLU-Gießen, Schlangenzahl 14, 35392, Giessen, Germany.
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50
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Bakare AB, Dean J, Chen Q, Thorat V, Huang Y, LaFramboise T, Lesnefsky EJ, Iyer S. Evaluating the Bioenergetics Health Index Ratio in Leigh Syndrome Fibroblasts to Understand Disease Severity. Int J Mol Sci 2021; 22:ijms221910344. [PMID: 34638685 PMCID: PMC8508996 DOI: 10.3390/ijms221910344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 09/23/2021] [Accepted: 09/23/2021] [Indexed: 12/21/2022] Open
Abstract
Several pediatric mitochondrial disorders, including Leigh syndrome (LS), impact mitochondrial (mt) genetics, development, and metabolism, leading to complex pathologies and energy failure. The extent to which pathogenic mtDNA variants regulate disease severity in LS is currently not well understood. To better understand this relationship, we computed a glycolytic bioenergetics health index (BHI) for measuring mitochondrial dysfunction in LS patient fibroblast cells harboring varying percentages of pathogenic mutant mtDNA (T8993G, T9185C) exhibiting deficiency in complex V or complex I (T10158C, T12706C). A high percentage (>90%) of pathogenic mtDNA in cells affecting complex V and a low percentage (<39%) of pathogenic mtDNA in cells affecting complex I was quantified. Levels of defective enzyme activities of the electron transport chain correlated with the percentage of pathogenic mtDNA. Subsequent bioenergetics assays showed cell lines relied on both OXPHOS and glycolysis for meeting energy requirements. Results suggest that whereas the precise mechanism of LS has not been elucidated, a multi-pronged approach taking into consideration the specific pathogenic mtDNA variant, glycolytic BHI, and the composite BHI (average ratio of oxphos to glycolysis) can aid in better understanding the factors influencing disease severity in LS.
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Affiliation(s)
- Ajibola B. Bakare
- Department of Biological Sciences, J. William Fulbright College of Arts and Sciences, University of Arkansas, Fayetteville, AR 72701, USA;
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA
| | - Joseph Dean
- Cardiology Section Medical Service, McGuire Veterans Affairs Medical Center, Richmond, VA 23284, USA; (J.D.); (E.J.L.)
| | - Qun Chen
- Pauley Heart Center, Division of Cardiology, Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA 23284, USA;
| | - Vedant Thorat
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; (V.T.); (Y.H.); (T.L.)
| | - Yimin Huang
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; (V.T.); (Y.H.); (T.L.)
| | - Thomas LaFramboise
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA; (V.T.); (Y.H.); (T.L.)
| | - Edward J. Lesnefsky
- Cardiology Section Medical Service, McGuire Veterans Affairs Medical Center, Richmond, VA 23284, USA; (J.D.); (E.J.L.)
- Pauley Heart Center, Division of Cardiology, Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA 23284, USA;
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Shilpa Iyer
- Department of Biological Sciences, J. William Fulbright College of Arts and Sciences, University of Arkansas, Fayetteville, AR 72701, USA;
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA
- Correspondence: ; Tel.: +1-(479)-575-3400
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