1
|
Yen HC, Hsu CT, Wu SY, Kan CC, Chang CW, Chang HM, Chien YA, Wei YH, Wu CY. Alterations in coenzyme Q 10 status in a cybrid line harboring the 3243A>G mutation of mitochondrial DNA is associated with abnormal mitochondrial bioenergetics and dysregulated mitochondrial biogenesis. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2024; 1865:149492. [PMID: 38960080 DOI: 10.1016/j.bbabio.2024.149492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Revised: 06/19/2024] [Accepted: 06/27/2024] [Indexed: 07/05/2024]
Abstract
Mitochondrial DNA (mtDNA) mutations, including the m.3243A>G mutation that causes mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS), are associated with secondary coenzyme Q10 (CoQ10) deficiency. We previously demonstrated that PPARGC1A knockdown repressed the expression of PDSS2 and several COQ genes. In the present study, we compared the mitochondrial function, CoQ10 status, and levels of PDSS and COQ proteins and genes between mutant cybrids harboring the m.3243A>G mutation and wild-type cybrids. Decreased mitochondrial energy production, defective respiratory function, and reduced CoQ10 levels were observed in the mutant cybrids. The ubiquinol-10:ubiquinone-10 ratio was lower in the mutant cybrids, indicating blockage of the electron transfer upstream of CoQ, as evident from the reduced ratio upon rotenone treatment and increased ratio upon antimycin A treatment in 143B cells. The mutant cybrids exhibited downregulation of PDSS2 and several COQ genes and upregulation of COQ8A. In these cybrids, the levels of PDSS2, COQ3-a isoform, COQ4, and COQ9 were reduced, whereas those of COQ3-b and COQ8A were elevated. The mutant cybrids had repressed PPARGC1A expression, elevated ATP5A levels, and reduced levels of mtDNA-encoded proteins, nuclear DNA-encoded subunits of respiratory enzyme complexes, MNRR1, cytochrome c, and DHODH, but no change in TFAM, TOM20, and VDAC1 levels. Alterations in the CoQ10 level in MELAS may be associated with mitochondrial energy deficiency and abnormal gene regulation. The finding of a reduction in the ubiquinol-10:ubiquinone-10 ratio in the MELAS mutant cybrids differs from our previous discovery that cybrids harboring the m.8344A>G mutation exhibit a high ubiquinol-10:ubiquinone-10 ratio.
Collapse
Affiliation(s)
- Hsiu-Chuan Yen
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Department of Nephrology, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
| | - Chia-Tzu Hsu
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Shin-Yu Wu
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chia-Chi Kan
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chun-Wei Chang
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Hsing-Ming Chang
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yu-An Chien
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yau-Huei Wei
- Center for Mitochondrial Medicine and Free Radical Research, Changhua Christian Hospital, Changhua, Taiwan
| | - Chun-Yen Wu
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| |
Collapse
|
2
|
Ding Y, Yu XJ, Guo QX, Leng JH. Functional analysis of the novel mitochondrial tRNA Trp and tRNA Ser(AGY) variants associated with type 2 diabetes mellitus. World J Diabetes 2024; 15:1753-1763. [PMID: 39192858 PMCID: PMC11346085 DOI: 10.4239/wjd.v15.i8.1753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 05/09/2024] [Accepted: 06/18/2024] [Indexed: 07/25/2024] Open
Abstract
BACKGROUND Mutations in mitochondrial tRNA (mt-tRNA) genes that result in mitochondrial dysfunction play important roles in type 2 diabetes mellitus (T2DM). We pre-viously reported a large Chinese pedigree with maternally inherited T2DM that harbors novel mt-tRNA Trp A5514G and tRNA Ser(AGY) C12237T variants, however, the effects of these mt-tRNA variants on T2DM progression are largely unknown. AIM To assess the potential pathogenicity of T2DM-associated m.A5514G and m.C12237T variants at genetic, molecular, and biochemical levels. METHODS Cytoplasmic hybrid (cybrid) cells carrying both m.A5514G and m.C12237T variants, and healthy control cells without these mitochondrial DNA (mtDNA) variants were generated using trans-mitochondrial technology. Mitochondrial features, including mt-tRNA steady-state level, levels of adenosine triphosphate (ATP), mitochondrial membrane potential (MMP), reactive oxygen species (ROS), mtDNA copy number, nicotinamide adenine dinucleotide (NAD+)/NADH ratio, enzymatic activities of respiratory chain complexes (RCCs), 8-hydroxy-deo-xyguanine (8-OhdG), malondialdehyde (MDA), and superoxide dismutase (SOD) were examined in cell lines with and without these mt-tRNA variants. RESULTS Compared with control cells, the m.A5514G variant caused an approximately 35% reduction in the steady-state level of mt-tRNA Trp (P < 0.0001); however, the m.C12237T variant did not affect the mt-tRNA Ser(AGY) steady-state level (P = 0.5849). Biochemical analysis revealed that cells with both m.A5514G and m.C12237T variants exhibited more severe mitochondrial dysfunctions and elevated oxidative stress than control cells: ATP, MMP, NAD+/NADH ratio, enzyme activities of RCCs and SOD levels were markedly decreased in mutant cells (P < 0.05 for all measures). By contrast, the levels of ROS, 8-OhdG and MDA were significantly increased (P < 0.05 for all measures), but mtDNA copy number was not affected by m.A5514G and m.C12237T variants (P = 0.5942). CONCLUSION The m.A5514G variant impaired mt-tRNA Trp metabolism, which subsequently caused mitochondrial dysfunction. The m.C12237T variant did not alter the steady-state level of mt-tRNA Ser(AGY), indicating that it may be a modifier of the m.A5514G variant. The m.A5514G variant may exacerbate the pathogenesis and progression of T2DM in this Chinese pedigree.
Collapse
Affiliation(s)
- Yu Ding
- Central Laboratory, Hangzhou First People’s Hospital, Hangzhou 310006, Zhejiang Province, China
| | - Xue-Jiao Yu
- Clinical Laboratory, Quzhou People’s Hospital, Quzhou 324000, Zhejiang Province, China
| | - Qin-Xian Guo
- Central Laboratory, Hangzhou First People’s Hospital, Hangzhou 310006, Zhejiang Province, China
| | - Jian-Hang Leng
- Central Laboratory, Hangzhou First People’s Hospital, Hangzhou 310006, Zhejiang Province, China
| |
Collapse
|
3
|
Sakamoto N, Hamada S, Takahashi H, Satou R, Suzuki M, Maeno T. Improvement of Intestinal Pseudo-Obstruction by Total Parenteral Nutrition in a Young Woman With Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-Like Episodes: A Case Report. Cureus 2023; 15:e50075. [PMID: 38186459 PMCID: PMC10769865 DOI: 10.7759/cureus.50075] [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] [Accepted: 12/06/2023] [Indexed: 01/09/2024] Open
Abstract
Patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), a mitochondrial disease, develop various types of organ failure, including intestinal pseudo-obstruction (IPO). We treated a patient with IPO that improved with total parenteral nutrition. A 20-year-old woman with a two-year history of diabetes mellitus was taking sitagliptin but her hemoglobin A1c (HbA1c) levels began increasing. After receiving metformin, she suffered a stroke-like attack and was diagnosed with MELAS. After persistent anorexia, she presented with symptoms of IPO, such as vomiting and gastrointestinal dilatation. After about 10 days of total parenteral nutrition, intestinal peristalsis improved and bowel movements resumed. She was able to resume her normal diet, and glycemic control with insulin glargine has allowed her to return to her daily life without gastrointestinal symptoms for over six months. Total parenteral nutrition may be effective for MELAS with IPO, and good glycemic control can prevent the need for incretin-related drugs, thus reducing the likelihood of recurrent IPO.
Collapse
Affiliation(s)
- Naoto Sakamoto
- Department of Primary Care and Medical Education, Institute of Medicine, University of Tsukuba, Tsukuba, JPN
| | - Shuhei Hamada
- Department of Primary Care and Medical Education, Institute of Medicine, University of Tsukuba, Tsukuba, JPN
| | - Hiroki Takahashi
- Department of General Medicine, Taito Municipal Hospital, Tokyo, JPN
| | - Rumi Satou
- Department of Internal Medicine, Kamisu Saiseikai Hospital, Kamisu, JPN
| | - Masatsune Suzuki
- Department of Primary Care and Medical Education, Institute of Medicine, University of Tsukuba, Tsukuba, JPN
| | - Tetsuhiro Maeno
- Department of Primary Care and Medical Education, Institute of Medicine, University of Tsukuba, Tsukuba, JPN
| |
Collapse
|
4
|
Zhang J, Koolmeister C, Han J, Filograna R, Hanke L, Àdori M, Sheward DJ, Teifel S, Gopalakrishna S, Shao Q, Liu Y, Zhu K, Harris RA, McInerney G, Murrell B, Aoun M, Bäckdahl L, Holmdahl R, Pekalski M, Wedell A, Engvall M, Wredenberg A, Karlsson Hedestam GB, Castro Dopico X, Rorbach J. Antigen receptor stimulation induces purifying selection against pathogenic mitochondrial tRNA mutations. JCI Insight 2023; 8:e167656. [PMID: 37681412 PMCID: PMC10544217 DOI: 10.1172/jci.insight.167656] [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: 12/06/2022] [Accepted: 07/27/2023] [Indexed: 09/09/2023] Open
Abstract
Pathogenic mutations in mitochondrial (mt) tRNA genes that compromise oxidative phosphorylation (OXPHOS) exhibit heteroplasmy and cause a range of multisyndromic conditions. Although mitochondrial disease patients are known to suffer from abnormal immune responses, how heteroplasmic mtDNA mutations affect the immune system at the molecular level is largely unknown. Here, in mice carrying pathogenic C5024T in mt-tRNAAla and in patients with mitochondrial encephalomyopathy, lactic acidosis, stroke-like episodes (MELAS) syndrome carrying A3243G in mt-tRNALeu, we found memory T and B cells to have lower pathogenic mtDNA mutation burdens than their antigen-inexperienced naive counterparts, including after vaccination. Pathogenic burden reduction was less pronounced in myeloid compared with lymphoid lineages, despite C5024T compromising macrophage OXPHOS capacity. Rapid dilution of the C5024T mutation in T and B cell cultures could be induced by antigen receptor-triggered proliferation and was accelerated by metabolic stress conditions. Furthermore, we found C5024T to dysregulate CD8+ T cell metabolic remodeling and IFN-γ production after activation. Together, our data illustrate that the generation of memory lymphocytes shapes the mtDNA landscape, wherein pathogenic variants dysregulate the immune response.
Collapse
Affiliation(s)
- Jingdian Zhang
- Department of Medical Biochemistry and Biophysics, and
- Max Planck Institute Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Camilla Koolmeister
- Department of Medical Biochemistry and Biophysics, and
- Max Planck Institute Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Jinming Han
- Applied Immunology and Immunotherapy, Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Roberta Filograna
- Department of Medical Biochemistry and Biophysics, and
- Max Planck Institute Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Leo Hanke
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Monika Àdori
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Daniel J. Sheward
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Sina Teifel
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Shreekara Gopalakrishna
- Department of Medical Biochemistry and Biophysics, and
- Max Planck Institute Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Qiuya Shao
- Department of Medical Biochemistry and Biophysics, and
- Max Planck Institute Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Yong Liu
- Department of Medical Biochemistry and Biophysics, and
- Max Planck Institute Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Keying Zhu
- Applied Immunology and Immunotherapy, Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Robert A. Harris
- Applied Immunology and Immunotherapy, Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Gerald McInerney
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Ben Murrell
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Mike Aoun
- Division of Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Liselotte Bäckdahl
- Division of Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Rikard Holmdahl
- Division of Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Marcin Pekalski
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Anna Wedell
- Max Planck Institute Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Center for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Martin Engvall
- Center for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Anna Wredenberg
- Department of Medical Biochemistry and Biophysics, and
- Max Planck Institute Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
- Center for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
| | | | - Xaquin Castro Dopico
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Joanna Rorbach
- Department of Medical Biochemistry and Biophysics, and
- Max Planck Institute Biology of Ageing-Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|
5
|
Ryytty S, Hämäläinen RH. The Mitochondrial m.3243A>G Mutation on the Dish, Lessons from In Vitro Models. Int J Mol Sci 2023; 24:13478. [PMID: 37686280 PMCID: PMC10487608 DOI: 10.3390/ijms241713478] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 08/28/2023] [Accepted: 08/29/2023] [Indexed: 09/10/2023] Open
Abstract
The m.3243A>G mutation in the tRNA Leu(UUR) gene (MT-TL1) is one of the most common pathogenic point mutations in human mtDNA. Patient symptoms vary widely and the severity of the disease ranges from asymptomatic to lethal. The reason for the high heterogeneity of m.3243A>G-associated disease is still unknown, and the treatment options are limited, with only supportive interventions available. Furthermore, the heteroplasmic nature of the m.3243A>G mutation and lack of specific animal models of mtDNA mutations have challenged the study of m.3243A>G, and, besides patient data, only cell models have been available for studies. The most commonly used cell models are patient derived, such as fibroblasts and induced pluripotent stem cell (iPSC)-derived models, and cybrid models where the mutant DNA is transferred to an acceptor cell. Studies on cell models have revealed cell-type-specific effects of the m.3243A>G mutation and that the tolerance for this mutation varies between cell types and between patients. In this review, we summarize the literature on the effects of m.3243A>G in cell models.
Collapse
Affiliation(s)
| | - Riikka H. Hämäläinen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Neulaniementie 2, 70211 Kuopio, Finland;
| |
Collapse
|
6
|
Feng J, Chen Z, Liang W, Wei Z, Ding G. Roles of Mitochondrial DNA Damage in Kidney Diseases: A New Biomarker. Int J Mol Sci 2022; 23:ijms232315166. [PMID: 36499488 PMCID: PMC9735745 DOI: 10.3390/ijms232315166] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/27/2022] [Accepted: 11/28/2022] [Indexed: 12/05/2022] Open
Abstract
The kidney is a mitochondria-rich organ, and kidney diseases are recognized as mitochondria-related pathologies. Intact mitochondrial DNA (mtDNA) maintains normal mitochondrial function. Mitochondrial dysfunction caused by mtDNA damage, including impaired mtDNA replication, mtDNA mutation, mtDNA leakage, and mtDNA methylation, is involved in the progression of kidney diseases. Herein, we review the roles of mtDNA damage in different setting of kidney diseases, including acute kidney injury (AKI) and chronic kidney disease (CKD). In a variety of kidney diseases, mtDNA damage is closely associated with loss of kidney function. The level of mtDNA in peripheral serum and urine also reflects the status of kidney injury. Alleviating mtDNA damage can promote the recovery of mitochondrial function by exogenous drug treatment and thus reduce kidney injury. In short, we conclude that mtDNA damage may serve as a novel biomarker for assessing kidney injury in different causes of renal dysfunction, which provides a new theoretical basis for mtDNA-targeted intervention as a therapeutic option for kidney diseases.
Collapse
Affiliation(s)
- Jun Feng
- Division of Nephrology, Renmin Hospital of Wuhan University, Wuhan 430060, China
- Nephrology and Urology Research Institute of Wuhan University, Wuhan 430060, China
| | - Zhaowei Chen
- Division of Nephrology, Renmin Hospital of Wuhan University, Wuhan 430060, China
- Nephrology and Urology Research Institute of Wuhan University, Wuhan 430060, China
| | - Wei Liang
- Division of Nephrology, Renmin Hospital of Wuhan University, Wuhan 430060, China
- Nephrology and Urology Research Institute of Wuhan University, Wuhan 430060, China
| | - Zhongping Wei
- Division of Nephrology, Renmin Hospital of Wuhan University, Wuhan 430060, China
- Nephrology and Urology Research Institute of Wuhan University, Wuhan 430060, China
| | - Guohua Ding
- Division of Nephrology, Renmin Hospital of Wuhan University, Wuhan 430060, China
- Nephrology and Urology Research Institute of Wuhan University, Wuhan 430060, China
- Correspondence:
| |
Collapse
|
7
|
Al-Ghamdi BA, Al-Shamrani JM, El-Shehawi AM, Al-Johani I, Al-Otaibi BG. Role of mitochondrial DNA in diabetes Mellitus Type I and Type II. Saudi J Biol Sci 2022; 29:103434. [PMID: 36187456 PMCID: PMC9523097 DOI: 10.1016/j.sjbs.2022.103434] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 08/01/2022] [Accepted: 09/01/2022] [Indexed: 12/04/2022] Open
Abstract
Morbidity and mortality from diabetes mellitus and associated illnesses is a major problem across the globe. Anti-diabetic medicines must be improved despite existing breakthroughs in treatment approaches. Diabetes has been linked to mitochondrial dysfunction. As a result, particular mitochondrial diabetes kinds like MIDD (maternally inherited diabetes & deafness) and DAD (diabetic autonomic dysfunction) have been identified and studied (diabetes and Deafness). Some mutations as in mitochondrial DNA (mtDNA), that encodes for a significant portion of mitochondrial proteins as well as mitochondrial tRNA essential for mitochondrial protein biosynthesis, are responsible for hereditary mitochondrial diseases. Tissue-specificity and heteroplasmy have a role in the harmful phenotype of mtDNA mutations, making it difficult to generalise findings from one study to another. There are a huge increase in the number for mtDNA mutations related with human illnesses that have been identified using current sequencing technologies. In this study, we make a list on mtDNA mutations linked with diseases and diabetic illnesses and explore the methods by which they contribute to the pathology's emergence.
Collapse
Affiliation(s)
- Bandar Ali Al-Ghamdi
- Department of Cardiology and Cardiac Surgery, King Fahad Armed Forces Hospital, Jeddah, Saudi Arabia.,Department of Biotechnology, Taif University, Taif City, Saudi Arabia
| | | | | | - Intisar Al-Johani
- Department of Biotechnology, Taif University, Taif City, Saudi Arabia
| | | |
Collapse
|
8
|
Li D, Liang C, Zhang T, Marley JL, Zou W, Lian M, Ji D. Pathogenic mitochondrial DNA 3243A>G mutation: From genetics to phenotype. Front Genet 2022; 13:951185. [PMID: 36276941 PMCID: PMC9582660 DOI: 10.3389/fgene.2022.951185] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 09/26/2022] [Indexed: 11/13/2022] Open
Abstract
The mitochondrial DNA (mtDNA) m.3243A>G mutation is one of the most common pathogenic mtDNA variants, showing complex genetics, pathogenic molecular mechanisms, and phenotypes. In recent years, the prevention of mtDNA-related diseases has trended toward precision medicine strategies, such as preimplantation genetic diagnosis (PGD) and mitochondrial replacement therapy (MRT). These techniques are set to allow the birth of healthy children, but clinical implementation relies on thorough insights into mtDNA genetics. The genotype and phenotype of m.3243A>G vary greatly from mother to offspring, which compromises genetic counseling for the disease. This review is the first to systematically elaborate on the characteristics of the m.3243A>G mutation, from genetics to phenotype and the relationship between them, as well as the related influencing factors and potential strategies for preventing disease. These perceptions will provide clarity for clinicians providing genetic counseling to m.3243A>G patients.
Collapse
Affiliation(s)
- Danyang Li
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract (Anhui Medical University), Hefei, Anhui, China
| | - Chunmei Liang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract (Anhui Medical University), Hefei, Anhui, China
| | - Tao Zhang
- Department of Obstetrics and Gynecology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Jordan Lee Marley
- Wellcome Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Weiwei Zou
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract (Anhui Medical University), Hefei, Anhui, China
| | - Muqing Lian
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Dongmei Ji
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract (Anhui Medical University), Hefei, Anhui, China
- *Correspondence: Dongmei Ji,
| |
Collapse
|
9
|
Di Toro A, Urtis M, Narula N, Giuliani L, Grasso M, Pasotti M, Pellegrini C, Serio A, Pilotto A, Antoniazzi E, Rampino T, Magrassi L, Valentini A, Cavallini A, Scelsi L, Ghio S, Abelli M, Olivotto I, Porcu M, Gavazzi A, Kodama T, Arbustini E. Impediments to Heart Transplantation in Adults With MELAS:m.3243A>G Cardiomyopathy. J Am Coll Cardiol 2022; 80:1431-1443. [DOI: 10.1016/j.jacc.2022.04.067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/12/2022] [Accepted: 04/19/2022] [Indexed: 01/07/2023]
|
10
|
Ikeda T, Tani N, Hirokawa T, Ikeda K, Morioka F, Shida A, Aoki Y, Ishikawa T. Biodistribution of Insulin Following Massive Insulin Subcutaneous Injection. Intern Med 2022; 61:1999-2006. [PMID: 35283372 PMCID: PMC9334236 DOI: 10.2169/internalmedicine.7364-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A man in his 30s injected insulin several times into his abdomen and was found dead several hours later. Micropathological findings showed alveolar injury with hemorrhaging and cerebral parietal lobe nerve cell edema. Biochemical examinations showed that the blood insulin level was high, significantly so at the insulin injection sites. The blood glucose and C-peptide levels were low. The insulin level in the kidneys was low. In forensic medicine, a postmortem diagnosis of insulin subcutaneous injection is often difficult. When insulin injection is suspected, particularly high insulin levels can be expected at the insulin injection site, rather than in the blood.
Collapse
Affiliation(s)
- Tomoya Ikeda
- Department of Legal Medicine, Osaka City University Medical School, Japan
- Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center, c/o Department of Legal Medicine, Osaka City University Medical School, Japan
| | - Naoto Tani
- Department of Legal Medicine, Osaka City University Medical School, Japan
- Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center, c/o Department of Legal Medicine, Osaka City University Medical School, Japan
| | - Tatsuya Hirokawa
- Department of Legal Medicine, Osaka City University Medical School, Japan
- Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center, c/o Department of Legal Medicine, Osaka City University Medical School, Japan
| | - Kei Ikeda
- Department of Legal Medicine, Osaka City University Medical School, Japan
| | - Fumiya Morioka
- Department of Legal Medicine, Osaka City University Medical School, Japan
| | - Alissa Shida
- Department of Legal Medicine, Osaka City University Medical School, Japan
| | - Yayoi Aoki
- Department of Legal Medicine, Osaka City University Medical School, Japan
| | - Takaki Ishikawa
- Department of Legal Medicine, Osaka City University Medical School, Japan
- Forensic Autopsy Section, Medico-legal Consultation and Postmortem Investigation Support Center, c/o Department of Legal Medicine, Osaka City University Medical School, Japan
| |
Collapse
|
11
|
Metabolic Reprogramming of Ovarian Cancer Spheroids during Adhesion. Cancers (Basel) 2022; 14:cancers14061399. [PMID: 35326551 PMCID: PMC8946790 DOI: 10.3390/cancers14061399] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/10/2022] [Accepted: 02/24/2022] [Indexed: 02/04/2023] Open
Abstract
Ovarian cancer remains a deadly disease and its recurrence disease is due in part to the presence of disseminating ovarian cancer aggregates not removed by debulking surgery. During dissemination in a dynamic ascitic environment, the spheroid cells' metabolism is characterized by low respiration and fragmented mitochondria, a metabolic phenotype that may not support secondary outgrowth after adhesion. Here, we investigated how adhesion affects cellular respiration and substrate utilization of spheroids mimicking early stages of secondary metastasis. Using different glucose and oxygen levels, we investigated cellular metabolism at early time points of adherence (24 h and less) comparing slow and fast-developing disease models. We found that adhesion over time showed changes in cellular energy metabolism and substrate utilization, with a switch in the utilization of mostly glutamine to glucose but no changes in fatty acid oxidation. Interestingly, low glucose levels had less of an impact on cellular metabolism than hypoxia. A resilience to culture conditions and the capacity to utilize a broader spectrum of substrates more efficiently distinguished the highly aggressive cells from the cells representing slow-developing disease, suggesting a flexible metabolism contributes to the stem-like properties. These results indicate that adhesion to secondary sites initiates a metabolic switch in the oxidation of substrates that could support outgrowth and successful metastasis.
Collapse
|
12
|
Mizusawa N, Harada N, Iwata T, Ohigashi I, Itakura M, Yoshimoto K. Identification of protease serine S1 family member 53 as a mitochondrial protein in murine islet beta cells. Islets 2022; 14:1-13. [PMID: 34636707 PMCID: PMC8812782 DOI: 10.1080/19382014.2021.1982325] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The aim of this study was to identify genes that are specifically expressed in pancreatic islet β-cells (hereafter referred to as β-cells). Large-scale complementary DNA-sequencing analysis was performed for 3,429 expressed sequence tags derived from murine MIN6 β-cells, through homology comparisons using the GenBank database. Three individual ESTs were found to code for protease serine S1 family member 53 (Prss53). Prss53 mRNA is processed into both a short and long form, which encode 482 and 552 amino acids, respectively. Transient overexpression of myc-tagged Prss53 in COS-7 cells showed that Prss53 was strongly associated with the luminal surfaces of organellar membranes and that it underwent signal peptide cleavage and N-glycosylation. Immunoelectron microscopy and western blotting revealed that Prss53 localized to mitochondria in MIN6 cells. Short hairpin RNA-mediated Prss53 knockdown resulted in Ppargc1a downregulation and Ucp2 and Glut2 upregulation. JC-1 staining revealed that the mitochondria were depolarized in Prss53-knockdown MIN6 cells; however, no change was observed in glucose-stimulated insulin secretion. Our results suggest that mitochondrial Prss53 expression plays an important role in maintaining the health of β-cells.
Collapse
Affiliation(s)
- Noriko Mizusawa
- Department of Medical Pharmacology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
- CONTACT Noriko Mizusawa Department of Oral Bioscience, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-Kuramoto-cho, Tokushima City770-8504, Japan
| | - Nagakatsu Harada
- Department of Health and Nutrition, Faculty of Nursing and Nutrition, The University of Shimane, Shimane, Japan
| | - Takeo Iwata
- Department of Functional Morphology, Faculty of Pharmaceutical Sciences, Niigata University of Pharmacy and Applied Life Sciences, Niigata, Japan
| | - Izumi Ohigashi
- Division of Experimental Immunology, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Mitsuo Itakura
- Division of Genetic Information, Institute for Genome Research, Tokushima University, Tokushima, Japan
| | - Katsuhiko Yoshimoto
- Department of Medical Pharmacology, Institute of Biomedical Sciences, Tokushima University, Tokushima, Japan
| |
Collapse
|
13
|
Rewiring cell signalling pathways in pathogenic mtDNA mutations. Trends Cell Biol 2021; 32:391-405. [PMID: 34836781 DOI: 10.1016/j.tcb.2021.10.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/19/2021] [Accepted: 10/22/2021] [Indexed: 12/24/2022]
Abstract
Mitochondria generate the energy to sustain cell viability and serve as a hub for cell signalling. Their own genome (mtDNA) encodes genes critical for oxidative phosphorylation. Mutations of mtDNA cause major disease and disability with a wide range of presentations and severity. We review here an emerging body of data suggesting that changes in cell metabolism and signalling pathways in response to the presence of mtDNA mutations play a key role in shaping disease presentation and progression. Understanding the impact of mtDNA mutations on cellular energy homeostasis and signalling pathways seems fundamental to identify novel therapeutic interventions with the potential to improve the prognosis for patients with primary mitochondrial disease.
Collapse
|
14
|
Constitutive activation of the PI3K-Akt-mTORC1 pathway sustains the m.3243 A > G mtDNA mutation. Nat Commun 2021; 12:6409. [PMID: 34737295 PMCID: PMC8568893 DOI: 10.1038/s41467-021-26746-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 10/20/2021] [Indexed: 11/25/2022] Open
Abstract
Mutations of the mitochondrial genome (mtDNA) cause a range of profoundly debilitating clinical conditions for which treatment options are very limited. Most mtDNA diseases show heteroplasmy – tissues express both wild-type and mutant mtDNA. While the level of heteroplasmy broadly correlates with disease severity, the relationships between specific mtDNA mutations, heteroplasmy, disease phenotype and severity are poorly understood. We have carried out extensive bioenergetic, metabolomic and RNAseq studies on heteroplasmic patient-derived cells carrying the most prevalent disease related mtDNA mutation, the m.3243 A > G. These studies reveal that the mutation promotes changes in metabolites which are associated with the upregulation of the PI3K-Akt-mTORC1 axis in patient-derived cells and tissues. Remarkably, pharmacological inhibition of PI3K, Akt, or mTORC1 reduced mtDNA mutant load and partially rescued cellular bioenergetic function. The PI3K-Akt-mTORC1 axis thus represents a potential therapeutic target that may benefit people suffering from the consequences of the m.3243 A > G mutation. Heteroplasmic mtDNA mutations cause disease in humans. Here, Chung et al find the PI3K-Akt-mTORC1 pathway constitutively activated in cells with the heteroplasmic m.3243 A > G mutation, and inhibition of the pathway cell autonomously reduces mutant mtDNA load and rescues mitochondrial bioenergetics.
Collapse
|
15
|
Mullin NK, Anfinson KR, Riker MJ, Wieland KL, Tatro NJ, Scheetz TE, Mullins RF, Stone EM, Tucker BA. Sensitive quantification of m.3243A>G mutational proportion in non-retinal tissues and its relationship with visual symptoms. Hum Mol Genet 2021; 31:775-782. [PMID: 34590675 DOI: 10.1093/hmg/ddab289] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 12/13/2022] Open
Abstract
The m.3243A>G mutation in the mitochondrial genome commonly causes retinal degeneration in patients with maternally inherited diabetes and deafness (MIDD) and mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). Like other mitochondrial mutations, m.3243A>G is inherited from the mother with a variable proportion of wild type and mutant mitochondrial genomes in different cells. The mechanism by which the m.3243A>G variant in each tissue relates to the manifestation of disease phenotype is not fully understood. Using a digital PCR assay we found that the % m.3243G in skin derived dermal fibroblasts was positively correlated with that of blood from the same individual. The % m.3243G detected in fibroblast cultures remained constant over multiple passages and was negatively correlated with mtDNA copy number. Although the % m.3243G present in blood was not correlated with severity of vision loss, as quantified by Goldmann visual field, a significant negative correlation between % m.3243G and the age of onset of visual symptoms was detected. Together, these results indicate that precise measurement of % m.3243G in clinically accessible tissues such as skin and blood may yield information relevant to the management of retinal m.3243A>G associated disease.
Collapse
Affiliation(s)
- Nathaniel K Mullin
- University of Iowa Institute for Vision Research, Iowa City, IA, 52242, United States
| | - Kristin R Anfinson
- University of Iowa Institute for Vision Research, Iowa City, IA, 52242, United States
| | - Megan J Riker
- University of Iowa Institute for Vision Research, Iowa City, IA, 52242, United States
| | - Kelsey L Wieland
- University of Iowa Institute for Vision Research, Iowa City, IA, 52242, United States
| | - Nicole J Tatro
- University of Iowa Institute for Vision Research, Iowa City, IA, 52242, United States
| | - Todd E Scheetz
- University of Iowa Institute for Vision Research, Iowa City, IA, 52242, United States
| | - Robert F Mullins
- University of Iowa Institute for Vision Research, Iowa City, IA, 52242, United States
| | - Edwin M Stone
- University of Iowa Institute for Vision Research, Iowa City, IA, 52242, United States
| | - Budd A Tucker
- University of Iowa Institute for Vision Research, Iowa City, IA, 52242, United States
| |
Collapse
|
16
|
Ratnaike TE, Greene D, Wei W, Sanchis-Juan A, Schon KR, van den Ameele J, Raymond L, Horvath R, Turro E, Chinnery PF. MitoPhen database: a human phenotype ontology-based approach to identify mitochondrial DNA diseases. Nucleic Acids Res 2021; 49:9686-9695. [PMID: 34428295 PMCID: PMC8464050 DOI: 10.1093/nar/gkab726] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/03/2021] [Accepted: 08/18/2021] [Indexed: 12/23/2022] Open
Abstract
Diagnosing mitochondrial disorders remains challenging. This is partly because the clinical phenotypes of patients overlap with those of other sporadic and inherited disorders. Although the widespread availability of genetic testing has increased the rate of diagnosis, the combination of phenotypic and genetic heterogeneity still makes it difficult to reach a timely molecular diagnosis with confidence. An objective, systematic method for describing the phenotypic spectra for each variant provides a potential solution to this problem. We curated the clinical phenotypes of 6688 published individuals with 89 pathogenic mitochondrial DNA (mtDNA) mutations, collating 26 348 human phenotype ontology (HPO) terms to establish the MitoPhen database. This enabled a hypothesis-free definition of mtDNA clinical syndromes, an overview of heteroplasmy-phenotype relationships, the identification of under-recognized phenotypes, and provides a publicly available reference dataset for objective clinical comparison with new patients using the HPO. Studying 77 patients with independently confirmed positive mtDNA diagnoses and 1083 confirmed rare disease cases with a non-mitochondrial nuclear genetic diagnosis, we show that HPO-based phenotype similarity scores can distinguish these two classes of rare disease patients with a false discovery rate <10% at a sensitivity of 80%. Enriching the MitoPhen database with more patients will improve predictions for increasingly rare variants.
Collapse
Affiliation(s)
- Thiloka E Ratnaike
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.,Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.,Department of Paediatrics, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK
| | - Daniel Greene
- Department of Haematology, University of Cambridge, NHS Blood and Transplant, Cambridge Biomedical Campus, Cambridge CB2 0PT, UK.,Medical Research Council Biostatistics Unit, Cambridge Biomedical Campus, Cambridge CB2 0SR, UK
| | - Wei Wei
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.,Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Alba Sanchis-Juan
- Department of Haematology, University of Cambridge, NHS Blood and Transplant, Cambridge Biomedical Campus, Cambridge CB2 0PT, UK
| | - Katherine R Schon
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.,Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.,Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Jelle van den Ameele
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.,Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Lucy Raymond
- Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Rita Horvath
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.,Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Ernest Turro
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Patrick F Chinnery
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK.,Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| |
Collapse
|
17
|
Pérez-Amado CJ, Bazan-Cordoba A, Hidalgo-Miranda A, Jiménez-Morales S. Mitochondrial Heteroplasmy Shifting as a Potential Biomarker of Cancer Progression. Int J Mol Sci 2021; 22:7369. [PMID: 34298989 PMCID: PMC8304746 DOI: 10.3390/ijms22147369] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/25/2021] [Accepted: 06/28/2021] [Indexed: 02/07/2023] Open
Abstract
Cancer is a serious health problem with a high mortality rate worldwide. Given the relevance of mitochondria in numerous physiological and pathological mechanisms, such as adenosine triphosphate (ATP) synthesis, apoptosis, metabolism, cancer progression and drug resistance, mitochondrial genome (mtDNA) analysis has become of great interest in the study of human diseases, including cancer. To date, a high number of variants and mutations have been identified in different types of tumors, which coexist with normal alleles, a phenomenon named heteroplasmy. This mechanism is considered an intermediate state between the fixation or elimination of the acquired mutations. It is suggested that mutations, which confer adaptive advantages to tumor growth and invasion, are enriched in malignant cells. Notably, many recent studies have reported a heteroplasmy-shifting phenomenon as a potential shaper in tumor progression and treatment response, and we suggest that each cancer type also has a unique mitochondrial heteroplasmy-shifting profile. So far, a plethora of data evidencing correlations among heteroplasmy and cancer-related phenotypes are available, but still, not authentic demonstrations, and whether the heteroplasmy or the variation in mtDNA copy number (mtCNV) in cancer are cause or consequence remained unknown. Further studies are needed to support these findings and decipher their clinical implications and impact in the field of drug discovery aimed at treating human cancer.
Collapse
Affiliation(s)
- Carlos Jhovani Pérez-Amado
- Laboratorio de Genómica del Cáncer, Instituto Nacional de Medicina Genómica, Mexico City 14610, Mexico; (C.J.P.-A.); (A.B.-C.); (A.H.-M.)
- Programa de Maestría y Doctorado, Posgrado en Ciencias Bioquímicas, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - Amellalli Bazan-Cordoba
- Laboratorio de Genómica del Cáncer, Instituto Nacional de Medicina Genómica, Mexico City 14610, Mexico; (C.J.P.-A.); (A.B.-C.); (A.H.-M.)
- Programa de Maestría y Doctorado, Posgrado en Ciencias Bioquímicas, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - Alfredo Hidalgo-Miranda
- Laboratorio de Genómica del Cáncer, Instituto Nacional de Medicina Genómica, Mexico City 14610, Mexico; (C.J.P.-A.); (A.B.-C.); (A.H.-M.)
| | - Silvia Jiménez-Morales
- Laboratorio de Genómica del Cáncer, Instituto Nacional de Medicina Genómica, Mexico City 14610, Mexico; (C.J.P.-A.); (A.B.-C.); (A.H.-M.)
| |
Collapse
|
18
|
The Role of Mitochondrial Mutations and Chronic Inflammation in Diabetes. Int J Mol Sci 2021; 22:ijms22136733. [PMID: 34201756 PMCID: PMC8268113 DOI: 10.3390/ijms22136733] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 06/16/2021] [Accepted: 06/19/2021] [Indexed: 02/07/2023] Open
Abstract
Diabetes mellitus and related disorders significantly contribute to morbidity and mortality worldwide. Despite the advances in the current therapeutic methods, further development of anti-diabetic therapies is necessary. Mitochondrial dysfunction is known to be implicated in diabetes development. Moreover, specific types of mitochondrial diabetes have been discovered, such as MIDD (maternally inherited diabetes and deafness) and DAD (diabetes and Deafness). Hereditary mitochondrial disorders are caused by certain mutations in the mitochondrial DNA (mtDNA), which encodes for a substantial part of mitochondrial proteins and mitochondrial tRNA necessary for mitochondrial protein synthesis. Study of mtDNA mutations is challenging because the pathogenic phenotype associated with such mutations depends on the level of its heteroplasmy (proportion of mtDNA copies carrying the mutation) and can be tissue-specific. Nevertheless, modern sequencing methods have allowed describing and characterizing a number of mtDNA mutations associated with human disorders, and the list is constantly growing. In this review, we provide a list of mtDNA mutations associated with diabetes and related disorders and discuss the mechanisms of their involvement in the pathology development.
Collapse
|
19
|
Zhunina OA, Yabbarov NG, Grechko AV, Starodubova AV, Ivanova E, Nikiforov NG, Orekhov AN. The Role of Mitochondrial Dysfunction in Vascular Disease, Tumorigenesis, and Diabetes. Front Mol Biosci 2021; 8:671908. [PMID: 34026846 PMCID: PMC8138126 DOI: 10.3389/fmolb.2021.671908] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 04/14/2021] [Indexed: 12/16/2022] Open
Abstract
Mitochondrial dysfunction is known to be associated with a wide range of human pathologies, such as cancer, metabolic, and cardiovascular diseases. One of the possible ways of mitochondrial involvement in the cellular damage is excessive production of reactive oxygen and nitrogen species (ROS and RNS) that cannot be effectively neutralized by existing antioxidant systems. In mitochondria, ROS and RNS can contribute to protein and mitochondrial DNA (mtDNA) damage causing failure of enzymatic chains and mutations that can impair mitochondrial function. These processes further lead to abnormal cell signaling, premature cell senescence, initiation of inflammation, and apoptosis. Recent studies have identified numerous mtDNA mutations associated with different human pathologies. Some of them result in imbalanced oxidative phosphorylation, while others affect mitochondrial protein synthesis. In this review, we discuss the role of mtDNA mutations in cancer, diabetes, cardiovascular diseases, and atherosclerosis. We provide a list of currently described mtDNA mutations associated with each pathology and discuss the possible future perspective of the research.
Collapse
Affiliation(s)
- Olga A. Zhunina
- Chemical Biology Department, Russian Research Center for Molecular Diagnostics and Therapy, Moscow, Russia
| | - Nikita G. Yabbarov
- Chemical Biology Department, Russian Research Center for Molecular Diagnostics and Therapy, Moscow, Russia
| | - Andrey V. Grechko
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia
| | | | - Ekaterina Ivanova
- Department of Basic Research, Skolkovo Innovative Center, Institute for Atherosclerosis Research, Moscow, Russia
| | - Nikita G. Nikiforov
- National Medical Research Center of Cardiology, Institute of Experimental Cardiology, Moscow, Russia
- Institute of Gene Biology, Moscow, Russia
- Laboratory of Cellular and Molecular Pathology of Cardiovascular System, Institute of Human Morphology, Moscow, Russia
| | - Alexander N. Orekhov
- Laboratory of Cellular and Molecular Pathology of Cardiovascular System, Institute of Human Morphology, Moscow, Russia
- Laboratory of Angiopathology, Institute of General Pathology and Pathophysiology, Moscow, Russia
| |
Collapse
|
20
|
Oishi N, Kubota D, Nakamoto K, Takeda Y, Hayashi M, Gocho K, Yamaki K, Igarashi T, Takahashi H, Kameya S. Multimodal imaging analysis of macular dystrophy in patient with maternally inherited diabetes and deafness (MIDD) with m.3243A>G mutation. Ophthalmic Genet 2021; 42:304-311. [PMID: 33541179 DOI: 10.1080/13816810.2021.1881978] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Purpose: Maternally inherited diabetes and deafness (MIDD) is caused by a heteroplasmic m.3243A>G mutation in the mitochondrial DNA. The main ocular feature in MIDD is macular dystrophy. The purpose of this study was to identify the phenotypical characteristics of a patient with MIDD by multimodal high-resolution imaging analyses.Methods: A detailed history and ophthalmic examination were performed on a 39-year-old patient with MIDD. Multi-modal imaging included fundus photography, fundus autofluorescence imaging, fluorescein angiography, spectral-domain optical coherence tomography, OCT-angiography, and adaptive optics imaging. The PCR-invader and whole exome sequencing (WES) methods were performed on the DNA of the patient.Results: A 39-year-old woman with sensorineural hearing loss, diabetes mellitus presented with atrophic perifoveal changes and MIDD was suspected. The PCR-invader and WES methods showed that the patient had a m.3243A>G mutation in the mitochondrial DNA with 29% and 16.7% of the heteroplasmy in the peripheral blood, respectively. Morphological analyses revealed that the areas of photoreceptor degeneration and chorioretinal atrophy were present mainly in the perifoveal region. Multifocal ERGs showed that the perifoveal responses were reduced. Goldmann visual field was significant for a cecocentral scotoma in the right eye and an enlarged blind spot in the left eye. The central isopter was constricted bilaterally. The results of high-resolution retinal imaging by AO revealed that the densities of the cone photoreceptor were significantly reduced in the fovea where no obvious atrophy of the RPE and choroid was observed.Conclusions: Our findings indicate that WES analysis can be used to detect the m.3243A>G mutation in the mtDNA. The results of multimodal imaging analyses indicated that the primary dysfunction of the photoreceptors in the fovea might precede the dysfunction of the RPE in patient with MIDD.
Collapse
Affiliation(s)
- Noriko Oishi
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| | - Daiki Kubota
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| | - Kenji Nakamoto
- Department of Ophthalmology, Nippon Medical School, Tokyo, Japan
| | - Yukito Takeda
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| | - Mika Hayashi
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| | - Kiyoko Gocho
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan.,Clinical Investigation Center 1423, Inserm and Quinze-Vingts National Ophthalmology Hospital, Paris, France
| | - Kunihiko Yamaki
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| | - Tsutomu Igarashi
- Department of Ophthalmology, Nippon Medical School, Tokyo, Japan
| | | | - Shuhei Kameya
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| |
Collapse
|
21
|
Prasun P. Role of mitochondria in pathogenesis of type 2 diabetes mellitus. J Diabetes Metab Disord 2020; 19:2017-2022. [PMID: 33520874 DOI: 10.1007/s40200-020-00679-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 10/28/2020] [Indexed: 01/09/2023]
Abstract
Type 2 diabetes mellitus (T2DM) is global health problem. An estimated 425 million people in the world had diabetes in 2017. It is a major cause of morbidity and mortality worldwide. Although, pathogenesis of T2DM and its complications have been focus of medical research for long, much remains to be learned. A better understanding of molecular pathogenesis is essential for more effective preventive and therapeutic interventions. Role of mitochondria in pathogenesis of metabolic problems such as obesity, metabolic syndrome, and T2DM is the focus of many recent research studies. Mitochondrial dysfunction contributes to the oxidative stress and systemic inflammation leading to insulin resistance (IR). Mitochondria are also essential for pancreatic beta cell insulin secretion. Hence, mitochondria are important players in the pathogenesis of T2DM. In this article, pathogenesis of T2DM is examined from a mitochondrial perspective.
Collapse
Affiliation(s)
- Pankaj Prasun
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place - Box 1497, New York, NY 10029 USA
| |
Collapse
|
22
|
Ding Q, Kucharczyk R, Zhao W, Dautant A, Xu S, Niedzwiecka K, Su X, Giraud MF, Gombeau K, Zhang M, Xie H, Zeng C, Bouhier M, di Rago JP, Liu Z, Tribouillard-Tanvier D, Chen H. Case Report: Identification of a Novel Variant (m.8909T>C) of Human Mitochondrial ATP6 Gene and Its Functional Consequences on Yeast ATP Synthase. Life (Basel) 2020; 10:life10090215. [PMID: 32971864 PMCID: PMC7555451 DOI: 10.3390/life10090215] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/09/2020] [Accepted: 09/17/2020] [Indexed: 11/16/2022] Open
Abstract
With the advent of next generation sequencing, the list of mitochondrial DNA (mtDNA) mutations identified in patients rapidly and continuously expands. They are frequently found in a limited number of cases, sometimes a single individual (as with the case herein reported) and in heterogeneous genetic backgrounds (heteroplasmy), which makes it difficult to conclude about their pathogenicity and functional consequences. As an organism amenable to mitochondrial DNA manipulation, able to survive by fermentation to loss-of-function mtDNA mutations, and where heteroplasmy is unstable, Saccharomyces cerevisiae is an excellent model for investigating novel human mtDNA variants, in isolation and in a controlled genetic context. We herein report the identification of a novel variant in mitochondrial ATP6 gene, m.8909T>C. It was found in combination with the well-known pathogenic m.3243A>G mutation in mt-tRNALeu. We show that an equivalent of the m.8909T>C mutation compromises yeast adenosine tri-phosphate (ATP) synthase assembly/stability and reduces the rate of mitochondrial ATP synthesis by 20-30% compared to wild type yeast. Other previously reported ATP6 mutations with a well-established pathogenicity (like m.8993T>C and m.9176T>C) were shown to have similar effects on yeast ATP synthase. It can be inferred that alone the m.8909T>C variant has the potential to compromise human health.
Collapse
Affiliation(s)
- Qiuju Ding
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing 211166, China; (Q.D.); (W.Z.); (S.X.); (M.Z.); (H.X.); (C.Z.); (Z.L.)
| | - Róża Kucharczyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 00090 Warsaw, Poland; (R.K.); (K.N.)
| | - Weiwei Zhao
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing 211166, China; (Q.D.); (W.Z.); (S.X.); (M.Z.); (H.X.); (C.Z.); (Z.L.)
| | - Alain Dautant
- Institut de Biochimie et Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, F-33000 Bordeaux, France; (A.D.); (X.S.); (M.-F.G.); (K.G.); (M.B.); (J.-P.d.R.)
| | - Shutian Xu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing 211166, China; (Q.D.); (W.Z.); (S.X.); (M.Z.); (H.X.); (C.Z.); (Z.L.)
| | - Katarzyna Niedzwiecka
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 00090 Warsaw, Poland; (R.K.); (K.N.)
| | - Xin Su
- Institut de Biochimie et Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, F-33000 Bordeaux, France; (A.D.); (X.S.); (M.-F.G.); (K.G.); (M.B.); (J.-P.d.R.)
| | - Marie-France Giraud
- Institut de Biochimie et Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, F-33000 Bordeaux, France; (A.D.); (X.S.); (M.-F.G.); (K.G.); (M.B.); (J.-P.d.R.)
| | - Kewin Gombeau
- Institut de Biochimie et Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, F-33000 Bordeaux, France; (A.D.); (X.S.); (M.-F.G.); (K.G.); (M.B.); (J.-P.d.R.)
| | - Mingchao Zhang
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing 211166, China; (Q.D.); (W.Z.); (S.X.); (M.Z.); (H.X.); (C.Z.); (Z.L.)
| | - Honglang Xie
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing 211166, China; (Q.D.); (W.Z.); (S.X.); (M.Z.); (H.X.); (C.Z.); (Z.L.)
| | - Caihong Zeng
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing 211166, China; (Q.D.); (W.Z.); (S.X.); (M.Z.); (H.X.); (C.Z.); (Z.L.)
| | - Marine Bouhier
- Institut de Biochimie et Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, F-33000 Bordeaux, France; (A.D.); (X.S.); (M.-F.G.); (K.G.); (M.B.); (J.-P.d.R.)
| | - Jean-Paul di Rago
- Institut de Biochimie et Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, F-33000 Bordeaux, France; (A.D.); (X.S.); (M.-F.G.); (K.G.); (M.B.); (J.-P.d.R.)
| | - Zhihong Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing 211166, China; (Q.D.); (W.Z.); (S.X.); (M.Z.); (H.X.); (C.Z.); (Z.L.)
| | - Déborah Tribouillard-Tanvier
- Institut de Biochimie et Génétique Cellulaires, Université de Bordeaux, CNRS, UMR 5095, F-33000 Bordeaux, France; (A.D.); (X.S.); (M.-F.G.); (K.G.); (M.B.); (J.-P.d.R.)
- Institut national de la santé et de la recherche médicale, 75000 Paris, France
- Correspondence: (D.T.-T.); (H.C.)
| | - Huimei Chen
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing 211166, China; (Q.D.); (W.Z.); (S.X.); (M.Z.); (H.X.); (C.Z.); (Z.L.)
- Correspondence: (D.T.-T.); (H.C.)
| |
Collapse
|
23
|
Bornstein R, Gonzalez B, Johnson SC. Mitochondrial pathways in human health and aging. Mitochondrion 2020; 54:72-84. [PMID: 32738358 PMCID: PMC7508824 DOI: 10.1016/j.mito.2020.07.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/20/2020] [Accepted: 07/27/2020] [Indexed: 12/27/2022]
Abstract
Mitochondria are eukaryotic organelles known best for their roles in energy production and metabolism. While often thought of as simply the 'powerhouse of the cell,' these organelles participate in a variety of critical cellular processes including reactive oxygen species (ROS) production, regulation of programmed cell death, modulation of inter- and intracellular nutrient signaling pathways, and maintenance of cellular proteostasis. Disrupted mitochondrial function is a hallmark of eukaryotic aging, and mitochondrial dysfunction has been reported to play a role in many aging-related diseases. While mitochondria are major players in human diseases, significant questions remain regarding their precise mechanistic role. In this review, we detail mechanisms by which mitochondrial dysfunction participate in disease and aging based on findings from model organisms and human genetics studies.
Collapse
Affiliation(s)
| | - Brenda Gonzalez
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Simon C Johnson
- Department of Neurology, University of Washington, Seattle, WA, USA; Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, USA; Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA.
| |
Collapse
|
24
|
Bayona-Bafaluy MP, Iglesias E, López-Gallardo E, Emperador S, Pacheu-Grau D, Labarta L, Montoya J, Ruiz-Pesini E. Genetic aspects of the oxidative phosphorylation dysfunction in dilated cardiomyopathy. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2020; 786:108334. [PMID: 33339579 DOI: 10.1016/j.mrrev.2020.108334] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 08/19/2020] [Accepted: 08/20/2020] [Indexed: 12/27/2022]
Abstract
Dilated cardiomyopathy is a frequent and extremely heterogeneous medical condition. Deficits in the oxidative phosphorylation system have been described in patients suffering from dilated cardiomyopathy. Hence, mutations in proteins related to this biochemical pathway could be etiological factors for some of these patients. Here, we review the clinical phenotypes of patients harboring pathological mutations in genes related to the oxidative phosphorylation system, either encoded in the mitochondrial or in the nuclear genome, presenting with dilated cardiomyopathy. In addition to the clinical heterogeneity of these patients, the large genetic heterogeneity has contributed to an improper allocation of pathogenicity for many candidate mutations. We suggest criteria to avoid incorrect assignment of pathogenicity to newly found mutations and discuss possible therapies targeting the oxidative phosphorylation function.
Collapse
Affiliation(s)
- M Pilar Bayona-Bafaluy
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain.
| | - Eldris Iglesias
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain.
| | - Ester López-Gallardo
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain.
| | - Sonia Emperador
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain.
| | - David Pacheu-Grau
- Department of Cellular Biochemistry, University Medical Center, Georg-August University,Humboldtalle, 23., 37073, Göttingen, Germany.
| | - Lorenzo Labarta
- Unidad de Cuidados Intensivos, Hospital San Jorge, Av. Martínez de Velasco, 36., 22004, Huesca, Spain.
| | - Julio Montoya
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain.
| | - Eduardo Ruiz-Pesini
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain; Fundación ARAID, Av. de Ranillas, 1-D., 50018, Zaragoza, Spain.
| |
Collapse
|
25
|
Shand JAD, Potter HC, Pilmore HL, Cundy T, Murphy R. Increased Peripheral Blood Heteroplasmy of the mt.3243A>G Mutation Is Associated with Earlier End-Stage Kidney Disease: A Case Report and Review of the Literature. Nephron Clin Pract 2020; 144:358-362. [PMID: 32434190 DOI: 10.1159/000507732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 04/05/2020] [Indexed: 11/19/2022] Open
Abstract
The mitochondrial DNA mutation mt.3243A>G is most commonly associated with maternally inherited diabetes and deafness (MIM 52,000), but it has protean phenotypes including renal disease due to focal segmental glomerulosclerosis. We describe monozygotic twins who both harboured this mutation and developed ESRD. Although otherwise genetically identical, the twins differed in their peripheral blood leucocyte levels of circulating mt.3243A>G heteroplasmy: 20 versus 10%, when assessed at 42 years of age. The twin with the higher heteroplasmy load developed end-stage kidney disease 15 years earlier than her sister. A review of the published literature supports a relationship between heteroplasmy level and the age at the development of the end stage of renal failure in patients with mt.3243A>G-related kidney disease.
Collapse
Affiliation(s)
- James A D Shand
- Department of Endocrinology and Diabetes, Auckland City Hospital, Auckland, New Zealand,
| | - Howard C Potter
- Molecular Pathology Laboratory, Canterbury Health Laboratories, Canterbury District Health Board, Christchurch, New Zealand
| | - Helen L Pilmore
- Department of Nephrology, Auckland City Hospital, Auckland, New Zealand.,Department of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Tim Cundy
- Department of Endocrinology and Diabetes, Auckland City Hospital, Auckland, New Zealand.,Department of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Rinki Murphy
- Department of Endocrinology and Diabetes, Auckland City Hospital, Auckland, New Zealand.,Department of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| |
Collapse
|
26
|
Pioglitazone and Deoxyribonucleoside Combination Treatment Increases Mitochondrial Respiratory Capacity in m.3243A>G MELAS Cybrid Cells. Int J Mol Sci 2020; 21:ijms21062139. [PMID: 32244971 PMCID: PMC7139379 DOI: 10.3390/ijms21062139] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 03/17/2020] [Accepted: 03/17/2020] [Indexed: 01/05/2023] Open
Abstract
The lack of effective treatments for mitochondrial disease has seen the development of new approaches, including those that aim to stimulate mitochondrial biogenesis to boost ATP generation above a critical disease threshold. Here, we examine the effects of the peroxisome proliferator-activated receptor γ (PPARγ) activator pioglitazone (PioG), in combination with deoxyribonucleosides (dNs), on mitochondrial biogenesis in cybrid cells containing >90% of the m.3243A>G mutation associated with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). PioG + dNs combination treatment increased mtDNA copy number and mitochondrial mass in both control (CON) and m.3243A>G (MUT) cybrids, with no adverse effects on cell proliferation. PioG + dNs also increased mtDNA-encoded transcripts in CON cybrids, but had the opposite effect in MUT cybrids, reducing the already elevated transcript levels. Steady-state levels of mature oxidative phosphorylation (OXPHOS) protein complexes were increased by PioG + dNs treatment in CON cybrids, but were unchanged in MUT cybrids. However, treatment was able to significantly increase maximal mitochondrial oxygen consumption rates and cell respiratory control ratios in both CON and MUT cybrids. Overall, these findings highlight the ability of PioG + dNs to improve mitochondrial respiratory function in cybrid cells containing the m.3243A>G MELAS mutation, as well as their potential for development into novel therapies to treat mitochondrial disease.
Collapse
|