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Ferreira T, Rodriguez S. Mitochondrial DNA: Inherent Complexities Relevant to Genetic Analyses. Genes (Basel) 2024; 15:617. [PMID: 38790246 PMCID: PMC11121663 DOI: 10.3390/genes15050617] [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: 04/17/2024] [Revised: 05/09/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024] Open
Abstract
Mitochondrial DNA (mtDNA) exhibits distinct characteristics distinguishing it from the nuclear genome, necessitating specific analytical methods in genetic studies. This comprehensive review explores the complex role of mtDNA in a variety of genetic studies, including genome-wide, epigenome-wide, and phenome-wide association studies, with a focus on its implications for human traits and diseases. Here, we discuss the structure and gene-encoding properties of mtDNA, along with the influence of environmental factors and epigenetic modifications on its function and variability. Particularly significant are the challenges posed by mtDNA's high mutation rate, heteroplasmy, and copy number variations, and their impact on disease susceptibility and population genetic analyses. The review also highlights recent advances in methodological approaches that enhance our understanding of mtDNA associations, advocating for refined genetic research techniques that accommodate its complexities. By providing a comprehensive overview of the intricacies of mtDNA, this paper underscores the need for an integrated approach to genetic studies that considers the unique properties of mitochondrial genetics. Our findings aim to inform future research and encourage the development of innovative methodologies to better interpret the broad implications of mtDNA in human health and disease.
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Affiliation(s)
- Tomas Ferreira
- Bristol Medical School, University of Bristol, Bristol BS8 1UD, UK
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge CB2 0SL, UK
| | - Santiago Rodriguez
- Bristol Medical School, University of Bristol, Bristol BS8 1UD, UK
- MRC Integrative Epidemiology Unit, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol BS8 1QU, UK
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2
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Spano L, Etain B, Laplanche JL, Leboyer M, Gard S, Bellivier F, Marie-Claire C. Telomere length and mitochondrial DNA copy number in bipolar disorder: A sibling study. World J Biol Psychiatry 2022; 24:449-456. [PMID: 36193690 DOI: 10.1080/15622975.2022.2131907] [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] [Indexed: 10/24/2022]
Abstract
OBJECTIVES An accelerated cellular ageing has been observed in bipolar disorder (BD) using biomarkers such as telomere length (TL) and mitochondrial DNA copy number (mtDNAcn). Several risk factors might drive premature ageing in individuals with BD, including a familial predisposition. This study compared TL and mtDNAcn between individuals with BD and their (un)-affected siblings, and explored factors that may explain proband-sibling differences. METHODS Sixty individuals with BD and seventy-four siblings (34 affected with BD or mood disorders and 40 unaffected) were included. Quantitative polymerase chain reaction (qPCR) was used to measure TL and mtDNAcn from peripheral blood genomic DNA. RESULTS TL and mtDNAcn did not significantly differ between probands and their siblings, whatever these latter were affected or not with mood disorders. However, the correlation plots of TL or mtDNAcn in proband-sibling pairs suggested that some pairs were discordant. The within proband-sibling pairs differences for TL and mtDNAcn were not explained by differences in all tested factors. CONCLUSIONS This study shows that probands with BD and their siblings are concordant for TL and mtDNAcn suggesting that they may share some environmental or genetic determinants of these two biomarkers of cellular ageing.
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Affiliation(s)
- Luana Spano
- Université Paris Cité, Inserm, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France
| | - Bruno Etain
- Université Paris Cité, Inserm, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France.,Département de Psychiatrie et de Médecine Addictologique, Hôpitaux Lariboisière-Fernand Widal, GHU APHP.Nord - Université de Paris, Paris, France.,Fondation Fondamental, Créteil, France
| | - Jean-Louis Laplanche
- Université Paris Cité, Inserm, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France.,Département de Biochimie et Biologie Moléculaire, DMU BioGeM, Hôpitaux Lariboisière-Fernand Widal, GHU APHP.Nord - Université de Paris, Paris, France
| | - Marion Leboyer
- Fondation Fondamental, Créteil, France.,Université Paris Est Créteil, INSERM U955, IMRB, Translational Neuro-Psychiatry, Créteil, France.,AP-HP, Hôpitaux Universitaires Henri Mondor, Département Médico-Universitaire de Psychiatrie et d'Addictologie (DMU IMPACT), Fédération Hospitalo-Universitaire de Médecine de Précision en Psychiatrie (FHU ADAPT), Créteil, France
| | - Sébastien Gard
- Fondation Fondamental, Créteil, France.,Pôle de Psychiatrie Générale et Universitaire, Centre Hospitalier Charles Perrens, Bordeaux, France
| | - Frank Bellivier
- Université Paris Cité, Inserm, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France.,Département de Psychiatrie et de Médecine Addictologique, Hôpitaux Lariboisière-Fernand Widal, GHU APHP.Nord - Université de Paris, Paris, France
| | - Cynthia Marie-Claire
- Université Paris Cité, Inserm, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France
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3
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Sanglard LP, Kuehn LA, Snelling WM, Spangler ML. Influence of environmental factors and genetic variation on mitochondrial DNA copy number. J Anim Sci 2022; 100:6576804. [PMID: 35511236 PMCID: PMC9150079 DOI: 10.1093/jas/skac059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 02/24/2022] [Indexed: 01/21/2023] Open
Abstract
Mitochondrial DNA copy number (mtDNA CN) has been shown to be highly heritable and associated with traits of interest in humans. However, studies are lacking in the literature for livestock species such as beef cattle. In this study, 2,371 individuals from a crossbred beef population comprising the Germplasm Evaluation program from the U.S. Meat Animal Research Center had samples of blood, leucocyte, or semen collected for low-pass sequencing (LPS) that resulted in both nuclear DNA (nuDNA) and mitochondrial DNA (mtDNA) sequence reads. Mitochondrial DNA CN was estimated based on the ratio of mtDNA to nuDNA coverages. Genetic parameters for mtDNA CN were estimated from an animal model based on a genomic relationship matrix (~87K SNP from the nuDNA). Different models were used to test the effects of tissue, sex, age at sample collection, heterosis, and breed composition. Maternal effects, assessed by fitting a maternal additive component and by fitting eleven SNP on the mtDNA, were also obtained. As previously reported, mtDNA haplotypes were used to classify individuals into Taurine haplogroups (T1, T2, T3/T4, and T5). Estimates of heritability when fitting fixed effects in addition to the intercept were moderate, ranging from 0.11 to 0.31 depending on the model. From a model ignoring contemporary group, semen samples had the lowest mtDNA CN, as expected, followed by blood and leucocyte samples (P ≤ 0.001). The effect of sex and the linear and quadratic effects of age were significant (P ≤ 0.02) depending on the model. When significant, females had greater mtDNA CN than males. The effects of heterosis and maternal heterosis were not significant (P ≥ 0.47). The estimates of maternal and mtDNA heritability were near zero (≤0.03). Most of the samples (98%) were classified as haplogroup T3. Variation was observed in the mtDNA within Taurine haplogroups, which enabled the identification of 24 haplotypes. These results suggest that mtDNA CN is under nuclear genetic control and would respond favorably to selection.
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Affiliation(s)
- Leticia P Sanglard
- Department of Animal Science, University of Nebraska, Lincoln, NE 68583, USA
| | - Larry A Kuehn
- USDA, ARS, Roman L Hruska U.S. Meat Animal Research Center, Clay Center, NE 68933, USA
| | - Warren M Snelling
- USDA, ARS, Roman L Hruska U.S. Meat Animal Research Center, Clay Center, NE 68933, USA
| | - Matthew L Spangler
- Department of Animal Science, University of Nebraska, Lincoln, NE 68583, USA
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4
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Stier A, Monaghan P, Metcalfe NB. Experimental demonstration of prenatal programming of mitochondrial aerobic metabolism lasting until adulthood. Proc Biol Sci 2022; 289:20212679. [PMID: 35232239 PMCID: PMC8889197 DOI: 10.1098/rspb.2021.2679] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
It is increasingly being postulated that among-individual variation in mitochondrial function underlies variation in individual performance (e.g. growth rate) and state of health. It has been suggested (but not adequately tested) that environmental conditions experienced before birth could programme postnatal mitochondrial function, with persistent effects potentially lasting into adulthood. We tested this hypothesis in an avian model by experimentally manipulating prenatal conditions (incubation temperature and stability) and then measuring mitochondrial aerobic metabolism in blood cells from the same individuals during the middle of the growth period and at adulthood. Mitochondrial aerobic metabolism changed markedly across life stages, and parts of these age-related changes were influenced by the prenatal temperature conditions. A high incubation temperature induced a consistent and long-lasting increase in mitochondrial aerobic metabolism. Postnatal mitochondrial aerobic metabolism was positively associated with oxidative damage on DNA but not telomere length. While we detected significant within-individual consistency in mitochondrial aerobic metabolism across life stages, the prenatal temperature regime only accounted for a relatively small proportion (less than 20%) of the consistent among-individual differences we observed. Our results demonstrate that prenatal conditions can programme consistent and long-lasting differences in mitochondrial function, which could potentially underlie among-individual variation in performance and health state.
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Affiliation(s)
- Antoine Stier
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK.,Department of Biology, University of Turku, Turku, Finland.,Univ Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR 5023 LEHNA, F-69622 Villeurbanne, France
| | - Pat Monaghan
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - Neil B Metcalfe
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
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5
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Chung JK, Ahn YM, Kim SA, Joo EJ. Differences in mitochondrial DNA copy number between patients with bipolar I and II disorders. J Psychiatr Res 2022; 145:325-333. [PMID: 33190840 DOI: 10.1016/j.jpsychires.2020.11.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 10/08/2020] [Accepted: 11/05/2020] [Indexed: 02/01/2023]
Abstract
Mitochondria play a critical role in energy metabolism. Genetic, postmortem brain, and brain imaging studies of bipolar disorder (BD) patients indicated that mitochondrial dysfunction might explain BD pathophysiology. Mitochondrial function can be indirectly evaluated by measuring mitochondrial DNA (mtDNA) copy numbers. We recruited 186 bipolar I disorder (BD1) and 95 bipolar II disorder (BD2) patients, and age- and sex-matched controls. MtDNA copy numbers in peripheral blood cells were measured via quantitative polymerase chain reaction. We explored parameters (including age and clinical features) that might affect mtDNA copy numbers. We found that BD1 patients had a lower mtDNA copy number than controls and that mtDNA copy number was negatively associated with the number of mood episodes. BD2 patients had a higher mtDNA copy number than controls. Thus, changes in mitochondrial function may influence BD pathophysiology. The opposite directions of the association with mtDNA copy number in BD1 and BD2 patients suggests that the difference in pathophysiology may be associated with mitochondrial function.
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Affiliation(s)
- Jae Kyung Chung
- Department of Psychiatry, Eumsung-somang Hospital, Eumsung, Republic of Korea
| | - Yong Min Ahn
- Department of Neuropsychiatry, Seoul National University Hospital, Seoul, Republic of Korea; Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea; Institute of Human Behavioral Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea
| | - Soon Ae Kim
- Department of Pharmacology, School of Medicine, Eulji University, Daejeon, Republic of Korea.
| | - Eun-Jeong Joo
- Department of Neuropsychiatry, School of Medicine, Eulji University, Daejeon, Republic of Korea; Department of Psychiatry, Nowon Eulji Medical Center, Eulji University, Seoul, Republic of Korea.
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6
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Gentiluomo M, Giaccherini M, Gào X, Guo F, Stocker H, Schöttker B, Brenner H, Canzian F, Campa D. Genome-wide association study of mitochondrial copy number. Hum Mol Genet 2021; 31:1346-1355. [PMID: 34964454 DOI: 10.1093/hmg/ddab341] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 10/27/2021] [Accepted: 11/15/2021] [Indexed: 11/13/2022] Open
Abstract
Mitochondrial DNA copy number (mtDNAcn) variation has been associated with increased risk of several human diseases in epidemiological studies. The quantification of mtDNAcn performed with real-time PCR is currently considered the de facto standard among several techniques. However, the heterogeneity of the laboratory methods (DNA extraction, storage, processing) used could give rise to results that are difficult to compare and reproduce across different studies. Several lines of evidence suggest that mtDNAcn is influenced by nuclear and mitochondrial genetic variability, however this relation is largely unexplored. The aim of this work was to elucidate the genetic basis of mtDNAcn variation. We performed a genome-wide association study (GWAS) of mtDNAcn in 6836 subjects from the ESTHER prospective cohort, and included, as replication set, the summary statistics of a GWAS that used 295 150 participants from the UK Biobank. We observed two novel associations with mtDNAcn variation on chromosome 19 (rs117176661), and 12 (rs7136238) that reached statistical significance at the genome-wide level. A polygenic score that we called mitoscore including all known single nucleotide polymorphisms explained 1.11% of the variation of mtDNAcn (p = 5.93 × 10-7). In conclusion, we performed a GWAS on mtDNAcn, adding to the evidence of the genetic background of this trait.
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Affiliation(s)
- Manuel Gentiluomo
- Unit of Genetics, Department of Biology, University of Pisa, 56126, Italy
| | - Matteo Giaccherini
- Unit of Genetics, Department of Biology, University of Pisa, 56126, Italy.,Genomic Epidemiology Group, German Cancer Research Center (DKFZ), Heidelberg, 69120, Germany
| | - Xīn Gào
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, 69120, Germany
| | - Feng Guo
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, 69120, Germany
| | - Hannah Stocker
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, 69120, Germany.,Network Aging Research, Heidelberg University, Heidelberg, 69120, Germany
| | - Ben Schöttker
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, 69120, Germany.,Network Aging Research, Heidelberg University, Heidelberg, 69120, Germany
| | - Hermann Brenner
- Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, 69120, Germany.,Network Aging Research, Heidelberg University, Heidelberg, 69120, Germany.,Division of Preventive Oncology, German Cancer Research Center (DKFZ) and National Center for Tumor Diseases (NCT), Heidelberg, 69120, Germany.,German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ) Heidelberg, 69120, Germany
| | - Federico Canzian
- Genomic Epidemiology Group, German Cancer Research Center (DKFZ), Heidelberg, 69120, Germany
| | - Daniele Campa
- Unit of Genetics, Department of Biology, University of Pisa, 56126, Italy
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7
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Gupta R, Karczewski KJ, Howrigan D, Neale BM, Mootha VK. Human genetic analyses of organelles highlight the nucleus in age-related trait heritability. eLife 2021; 10:68610. [PMID: 34467851 PMCID: PMC8476128 DOI: 10.7554/elife.68610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Accepted: 08/30/2021] [Indexed: 12/15/2022] Open
Abstract
Most age-related human diseases are accompanied by a decline in cellular organelle integrity, including impaired lysosomal proteostasis and defective mitochondrial oxidative phosphorylation. An open question, however, is the degree to which inherited variation in or near genes encoding each organelle contributes to age-related disease pathogenesis. Here, we evaluate if genetic loci encoding organelle proteomes confer greater-than-expected age-related disease risk. As mitochondrial dysfunction is a 'hallmark' of aging, we begin by assessing nuclear and mitochondrial DNA loci near genes encoding the mitochondrial proteome and surprisingly observe a lack of enrichment across 24 age-related traits. Within nine other organelles, we find no enrichment with one exception: the nucleus, where enrichment emanates from nuclear transcription factors. In agreement, we find that genes encoding several organelles tend to be 'haplosufficient,' while we observe strong purifying selection against heterozygous protein-truncating variants impacting the nucleus. Our work identifies common variation near transcription factors as having outsize influence on age-related trait risk, motivating future efforts to determine if and how this inherited variation then contributes to observed age-related organelle deterioration.
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Affiliation(s)
- Rahul Gupta
- Howard Hughes Medical Institute and Department of Molecular Biology, Massachusetts General Hospital, Boston, United States.,Broad Institute of MIT and Harvard, Cambridge, United States.,Analytic and Translational Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, United States
| | - Konrad J Karczewski
- Broad Institute of MIT and Harvard, Cambridge, United States.,Analytic and Translational Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, United States
| | - Daniel Howrigan
- Broad Institute of MIT and Harvard, Cambridge, United States.,Analytic and Translational Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, United States
| | - Benjamin M Neale
- Broad Institute of MIT and Harvard, Cambridge, United States.,Analytic and Translational Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, United States
| | - Vamsi K Mootha
- Howard Hughes Medical Institute and Department of Molecular Biology, Massachusetts General Hospital, Boston, United States.,Broad Institute of MIT and Harvard, Cambridge, United States
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8
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Ganel L, Chen L, Christ R, Vangipurapu J, Young E, Das I, Kanchi K, Larson D, Regier A, Abel H, Kang CJ, Scott A, Havulinna A, Chiang CWK, Service S, Freimer N, Palotie A, Ripatti S, Kuusisto J, Boehnke M, Laakso M, Locke A, Stitziel NO, Hall IM. Mitochondrial genome copy number measured by DNA sequencing in human blood is strongly associated with metabolic traits via cell-type composition differences. Hum Genomics 2021; 15:34. [PMID: 34099068 PMCID: PMC8185936 DOI: 10.1186/s40246-021-00335-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 05/26/2021] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Mitochondrial genome copy number (MT-CN) varies among humans and across tissues and is highly heritable, but its causes and consequences are not well understood. When measured by bulk DNA sequencing in blood, MT-CN may reflect a combination of the number of mitochondria per cell and cell-type composition. Here, we studied MT-CN variation in blood-derived DNA from 19184 Finnish individuals using a combination of genome (N = 4163) and exome sequencing (N = 19034) data as well as imputed genotypes (N = 17718). RESULTS We identified two loci significantly associated with MT-CN variation: a common variant at the MYB-HBS1L locus (P = 1.6 × 10-8), which has previously been associated with numerous hematological parameters; and a burden of rare variants in the TMBIM1 gene (P = 3.0 × 10-8), which has been reported to protect against non-alcoholic fatty liver disease. We also found that MT-CN is strongly associated with insulin levels (P = 2.0 × 10-21) and other metabolic syndrome (metS)-related traits. Using a Mendelian randomization framework, we show evidence that MT-CN measured in blood is causally related to insulin levels. We then applied an MT-CN polygenic risk score (PRS) derived from Finnish data to the UK Biobank, where the association between the PRS and metS traits was replicated. Adjusting for cell counts largely eliminated these signals, suggesting that MT-CN affects metS via cell-type composition. CONCLUSION These results suggest that measurements of MT-CN in blood-derived DNA partially reflect differences in cell-type composition and that these differences are causally linked to insulin and related traits.
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Affiliation(s)
- Liron Ganel
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Lei Chen
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Ryan Christ
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
| | - Jagadish Vangipurapu
- Institute of Clinical Medicine, Internal Medicine, University of Eastern Finland, Kuopio, Finland
| | - Erica Young
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO, USA
| | - Indraniel Das
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
| | - Krishna Kanchi
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
| | - David Larson
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
| | - Allison Regier
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Haley Abel
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
| | - Chul Joo Kang
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
| | - Alexandra Scott
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Aki Havulinna
- Institute for Molecular Medicine Finland (FIMM), HiLIFE, University of Helsinki, Helsinki, Finland
- Finnish Institute for Health and Welfare (THL), Helsinki, Finland
| | - Charleston W K Chiang
- Center for Genetic Epidemiology, Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Quantitative and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Susan Service
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA, USA
| | - Nelson Freimer
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA, USA
| | - Aarno Palotie
- Institute for Molecular Medicine Finland (FIMM), HiLIFE, University of Helsinki, Helsinki, Finland
- Analytical and Translational Genetics Unit (ATGU), Psychiatric & Neurodevelopmental Genetics Unit, Departments of Psychiatry and Neurology, Massachusetts General Hospital, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Samuli Ripatti
- Institute for Molecular Medicine Finland (FIMM), HiLIFE, University of Helsinki, Helsinki, Finland
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Johanna Kuusisto
- Institute of Clinical Medicine, Internal Medicine, University of Eastern Finland, Kuopio, Finland
- Department of Medicine, Kuopio University Hospital, Kuopio, Finland
| | - Michael Boehnke
- Department of Biostatistics and Center for Statistical Genetics, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - Markku Laakso
- Institute of Clinical Medicine, Internal Medicine, University of Eastern Finland, Kuopio, Finland
- Department of Medicine, Kuopio University Hospital, Kuopio, Finland
| | - Adam Locke
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Nathan O Stitziel
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA.
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO, USA.
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA.
| | - Ira M Hall
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA.
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA.
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9
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Li R, Li S, Pan M, Chen H, Liu X, Chen G, Chen R, Yin S, Hu K, Mao Z, Huo W, Wang X, Yu S, Guo Y, Hou J, Wang C. Physical activity counteracted associations of exposure to mixture of air pollutants with mitochondrial DNA copy number among rural Chinese adults. CHEMOSPHERE 2021; 272:129907. [PMID: 33601207 DOI: 10.1016/j.chemosphere.2021.129907] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 02/01/2021] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Exposure to single air pollutant and physical activity (PA) were associated with an altered mitochondrial DNA copy number (mtDNA-CN). However, studies on the interactive effects of single or a mixture of air pollutants and PA on mtDNA-CN were limited. METHODS A total of 2707 Chinese adults were obtained from the Henan Rural Cohort Study. Spatiotemporal models were used to estimate particulate matter (PMs) (PM with an aerodynamic diameter ≤ 1.0 μm (PM1), ≤2.5 μm (PM2.5) or ≤ 10 μm (PM10)) and nitrogen dioxide (NO2) concentrations. Relative mtDNA-CN was measured by quantitative real-time polymerase chain reaction. Linear regression and quantile g-computation models were applied to examine associations of single or mixture of air pollutants with relative mtDNA-CN. The interactive effects of single or mixture of air pollutants and PA on relative mtDNA-CN were visualized by using Interaction plots. RESULTS Each 1 μg/m3 increment in PM1, PM2.5, PM10 or NO2 was associated with a 5.11% (95% confidence interval: 3.71%, 6.53%), 6.77% (4.81%, 8.76%), 3.05% (2.22%, 3.87%) or 4.99% (3.45%, 6.55%) increase in relative mtDNA-CN. Each one-quartile increment in mixture of the four air pollutants was related to a 0.053 (0.032, 0.075) increase in relative mtDNA-CN. Negative interaction effects of single or mixture of air pollutants and PA on relative mtDNA-CN were observed. CONCLUSIONS The positive associations of single or mixture of air pollutants with relative mtDNA-CN were counteracted by PA at certain levels, implying that PA may be a costless and effective approach to decrease negative effects of air pollution on mtDNA-CN.
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Affiliation(s)
- Ruiying Li
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Shanshan Li
- Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia
| | - Mingming Pan
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Hao Chen
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Xiaotian Liu
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Gongbo Chen
- Guangdong Provincial Engineering Technology Research Center of Environmental and Health Risk Assessment, Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou, 510080, China
| | - Ruoling Chen
- Faculty of Education, Health and Wellbeing, University of Wolverhampton, Wolverhampton, UK
| | - Shanshan Yin
- Department of health policy research, Henan Academy of Medical Sciences, Zhengzhou, China
| | - Kai Hu
- Department of health policy research, Henan Academy of Medical Sciences, Zhengzhou, China
| | - Zhenxing Mao
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Wenqian Huo
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Xian Wang
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Songcheng Yu
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China
| | - Yuming Guo
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China; Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia
| | - Jian Hou
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China.
| | - Chongjian Wang
- Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China.
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10
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Duan Y, Al-Jubury A, Kania PW, Buchmann K. Trematode diversity reflecting the community structure of Danish freshwater systems: molecular clues. Parasit Vectors 2021; 14:43. [PMID: 33436070 PMCID: PMC7805065 DOI: 10.1186/s13071-020-04536-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 12/10/2020] [Indexed: 02/07/2023] Open
Abstract
Background Digenean trematodes are parasitic platyhelminths that use several hosts in their life cycles and are thereby embedded in various ecosystems affected by local environmental conditions. Their presence in a habitat will reflect the presence of different host species and, as such, they can serve as ecological indicators. Only limited information on the occurrence of trematodes and their link to other trophic levels in the Danish freshwater ecosystems is currently available.Therefore, the main aim of the present study was to increase our knowledge in this field. Methods Snails were sampled from 21 freshwater lakes in Denmark, following which shedding procedures were performed, cercariae were recoved and the released parasites were identified using molecular tools (PCR and sequencing). Results A total of 5657 snail hosts belonging to ten species were identified, revealing a highly diverse parasite fauna comprising 22 trematode species. The overall trematode prevalence was 12.6%, but large variations occurred between host species. The snail host Lymnaea stagnalis showed the highest prevalence and also exhibited the highest diversity, accounting for 47.6% of the species richness. Conclusions This survey contributes updated information on parasite–host relations and compatibility and may assist in describing the ecological structure of the investigated Danish freshwater ecosystems. ![]()
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Affiliation(s)
- Yajiao Duan
- Laboratory of Aquatic Pathobiology, Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Via Stigbøjlen 7, 1870, Frederiksberg C, Copenhagen, Denmark.
| | - Azmi Al-Jubury
- Laboratory of Aquatic Pathobiology, Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Via Stigbøjlen 7, 1870, Frederiksberg C, Copenhagen, Denmark
| | - Per Walter Kania
- Laboratory of Aquatic Pathobiology, Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Via Stigbøjlen 7, 1870, Frederiksberg C, Copenhagen, Denmark
| | - Kurt Buchmann
- Laboratory of Aquatic Pathobiology, Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Via Stigbøjlen 7, 1870, Frederiksberg C, Copenhagen, Denmark
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11
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Deciphering the genetic and epidemiological landscape of mitochondrial DNA abundance. Hum Genet 2020; 140:849-861. [PMID: 33385171 PMCID: PMC8099832 DOI: 10.1007/s00439-020-02249-w] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 12/15/2020] [Indexed: 12/13/2022]
Abstract
Mitochondrial (MT) dysfunction is a hallmark of aging and has been associated with most aging-related diseases as well as immunological processes. However, little is known about aging, lifestyle and genetic factors influencing mitochondrial DNA (mtDNA) abundance. In this study, mtDNA abundance was estimated from the weighted intensities of probes mapping to the MT genome in 295,150 participants from the UK Biobank. We found that the abundance of mtDNA was significantly elevated in women compared to men, was negatively correlated with advanced age, higher smoking exposure, greater body-mass index, higher frailty index as well as elevated red and white blood cell count and lower mortality. In addition, several biochemistry markers in blood-related to cholesterol metabolism, ion homeostasis and kidney function were found to be significantly associated with mtDNA abundance. By performing a genome-wide association study, we identified 50 independent regions genome-wide significantly associated with mtDNA abundance which harbour multiple genes involved in the immune system, cancer as well as mitochondrial function. Using mixed effects models, we estimated the SNP-heritability of mtDNA abundance to be around 8%. To investigate the consequence of altered mtDNA abundance, we performed a phenome-wide association study and found that mtDNA abundance is involved in risk for leukaemia, hematologic diseases as well as hypertension. Thus, estimating mtDNA abundance from genotyping arrays has the potential to provide novel insights into age- and disease-relevant processes, particularly those related to immunity and established mitochondrial functions.
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12
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Filograna R, Mennuni M, Alsina D, Larsson NG. Mitochondrial DNA copy number in human disease: the more the better? FEBS Lett 2020; 595:976-1002. [PMID: 33314045 PMCID: PMC8247411 DOI: 10.1002/1873-3468.14021] [Citation(s) in RCA: 180] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 11/02/2020] [Accepted: 11/26/2020] [Indexed: 12/19/2022]
Abstract
Most of the genetic information has been lost or transferred to the nucleus during the evolution of mitochondria. Nevertheless, mitochondria have retained their own genome that is essential for oxidative phosphorylation (OXPHOS). In mammals, a gene‐dense circular mitochondrial DNA (mtDNA) of about 16.5 kb encodes 13 proteins, which constitute only 1% of the mitochondrial proteome. Mammalian mtDNA is present in thousands of copies per cell and mutations often affect only a fraction of them. Most pathogenic human mtDNA mutations are recessive and only cause OXPHOS defects if present above a certain critical threshold. However, emerging evidence strongly suggests that the proportion of mutated mtDNA copies is not the only determinant of disease but that also the absolute copy number matters. In this review, we critically discuss current knowledge of the role of mtDNA copy number regulation in various types of human diseases, including mitochondrial disorders, neurodegenerative disorders and cancer, and during ageing. We also provide an overview of new exciting therapeutic strategies to directly manipulate mtDNA to restore OXPHOS in mitochondrial diseases.
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Affiliation(s)
- Roberta Filograna
- Division of Molecular Metabolism, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Max Planck Institute for Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Mara Mennuni
- Division of Molecular Metabolism, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Max Planck Institute for Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - David Alsina
- Division of Molecular Metabolism, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Max Planck Institute for Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Nils-Göran Larsson
- Division of Molecular Metabolism, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Max Planck Institute for Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
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13
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Pavanello S, Campisi M, Mastrangelo G, Hoxha M, Bollati V. The effects of everyday-life exposure to polycyclic aromatic hydrocarbons on biological age indicators. Environ Health 2020; 19:128. [PMID: 33272294 PMCID: PMC7713168 DOI: 10.1186/s12940-020-00669-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 10/16/2020] [Indexed: 05/25/2023]
Abstract
BACKGROUND Further knowledge on modifiable aging risk factors is required to mitigate the increasing burden of age-related diseases in a rapidly growing global demographic of elderly individuals. We explored the effect of everyday exposure to polycyclic aromatic hydrocarbons (PAHs), which are fundamental constituents of air pollution, on cellular biological aging. This was determined via the analysis of leukocyte telomere length (LTL), mitochondrial DNA copy number (LmtDNAcn), and by the formation of anti-benzo[a]pyrene diolepoxide (B[a]PDE-DNA) adducts. METHODS The study population consisted of 585 individuals living in North-East Italy. PAH exposure (diet, indoor activities, outdoor activities, traffic, and residential exposure) and smoking behavior were assessed by questionnaire and anti-B[a]PDE-DNA by high-performance-liquid-chromatography. LTL, LmtDNAcn and genetic polymorphisms [glutathione S-transferase M1 and T1 (GSTM1; GSTT1)] were measured by polymerase chain reaction. Structural equation modelling analysis evaluated these complex relationships. RESULTS Anti-B[a]PDE-DNA enhanced with PAH exposure (p = 0.005) and active smoking (p = 0.0001), whereas decreased with detoxifying GSTM1 (p = 0.021) and in females (p = 0.0001). Subsequently, LTL and LmtDNAcn reduced with anti-B[a]PDE-DNA (p = 0.028 and p = 0.018), particularly in males (p = 0.006 and p = 0.0001). Only LTL shortened with age (p = 0.001) while elongated with active smoking (p = 0.0001). Besides this, the most significant determinants of PAH exposure that raised anti-B[a]PDE-DNA were indoor and diet (p = 0.0001), the least was outdoor (p = 0.003). CONCLUSION New findings stemming from our study suggest that certain preventable everyday life exposures to PAHs reduce LTL and LmtDNAcn. In particular, the clear association with indoor activities, diet, and gender opens new perspectives for tailored preventive measures in age-related diseases. CAPSULE Everyday life exposure to polycyclic aromatic hydrocarbons reduces leukocyte telomere length and mitochondrial DNA copy number through anti-B[a]PDE-DNA adduct formation.
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Affiliation(s)
- Sofia Pavanello
- Medicina del Lavoro, Dipartimento di Scienze Cardio- Toraco- Vascolari e Sanità Pubblica, Università di Padova, Padova, Italy
- Azienda Ospedaliera di Padova, Unità di Medicina del Lavoro, Padova, Italy
| | - Manuela Campisi
- Medicina del Lavoro, Dipartimento di Scienze Cardio- Toraco- Vascolari e Sanità Pubblica, Università di Padova, Padova, Italy
| | - Giuseppe Mastrangelo
- Medicina del Lavoro, Dipartimento di Scienze Cardio- Toraco- Vascolari e Sanità Pubblica, Università di Padova, Padova, Italy
| | - Mirjam Hoxha
- EPIGET – Epidemiology, Epigenetics and Toxicology Lab, Dipartimento di Scienze Cliniche e di Comunità, Università degli Studi di Milano, Milan, Italy
| | - Valentina Bollati
- EPIGET – Epidemiology, Epigenetics and Toxicology Lab, Dipartimento di Scienze Cliniche e di Comunità, Università degli Studi di Milano, Milan, Italy
- Dipartimento di Medicina Preventiva, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milano, Italy
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14
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Mengel-From J, Svane AM, Pertoldi C, Nygaard Kristensen T, Loeschcke V, Skytthe A, Christensen K, Lindahl-Jacobsen R, Hjelmborg J, Christiansen L. Advanced Parental Age at Conception and Sex Affects Mitochondrial DNA Copy Number in Human and Fruit Flies. J Gerontol A Biol Sci Med Sci 2020; 74:1853-1860. [PMID: 30874797 DOI: 10.1093/gerona/glz070] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 03/08/2019] [Indexed: 11/13/2022] Open
Abstract
Aging is a multifactorial trait caused by early as well as late-life circumstances. A society trend that parents deliberately delay having children is of concern to health professionals, for example as advanced parental age at conception increases disease risk profiles in offspring. We here aim to study if advanced parental age at conception affects mitochondrial DNA content, a cross-species biomarker of general health, in adult human twin offspring and in a model organism. We find no deteriorated mitochondrial DNA content at advanced parental age at conception, but human mitochondrial DNA content was higher in females than males, and the difference was twofold higher at advanced maternal age at conception. Similar parental age effects and sex-specific differences in mitochondrial DNA content were found in Drosophila melanogaster. In addition, parental longevity in humans associates with both mitochondrial DNA content and parental age at conception; thus, we carefully propose that a poorer disease risk profile from advanced parental age at conception might be surpassed by superior effects of parental successful late-life reproduction that associate with parental longevity.
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Affiliation(s)
- Jonas Mengel-From
- The Danish Aging Research Center and The Danish Twin Registry, Epidemiology and Biostatistics Unit, Institute of Public Health, University of Southern Denmark, Odense.,Department of Clinical Genetics, Odense University Hospital
| | - Anne Marie Svane
- The Danish Aging Research Center and The Danish Twin Registry, Epidemiology and Biostatistics Unit, Institute of Public Health, University of Southern Denmark, Odense
| | - Cino Pertoldi
- Section of Biology and Environmental Science, Department of Chemistry and Bioscience, Aalborg University.,Aalborg Zoo, Aarhus University, Denmark
| | - Torsten Nygaard Kristensen
- Section of Biology and Environmental Science, Department of Chemistry and Bioscience, Aalborg University.,Department of Bioscience, Aarhus University, Denmark
| | | | - Axel Skytthe
- The Danish Aging Research Center and The Danish Twin Registry, Epidemiology and Biostatistics Unit, Institute of Public Health, University of Southern Denmark, Odense
| | - Kaare Christensen
- The Danish Aging Research Center and The Danish Twin Registry, Epidemiology and Biostatistics Unit, Institute of Public Health, University of Southern Denmark, Odense.,Department of Clinical Genetics, Odense University Hospital
| | - Rune Lindahl-Jacobsen
- The Danish Aging Research Center and The Danish Twin Registry, Epidemiology and Biostatistics Unit, Institute of Public Health, University of Southern Denmark, Odense
| | - Jacob Hjelmborg
- The Danish Aging Research Center and The Danish Twin Registry, Epidemiology and Biostatistics Unit, Institute of Public Health, University of Southern Denmark, Odense
| | - Lene Christiansen
- The Danish Aging Research Center and The Danish Twin Registry, Epidemiology and Biostatistics Unit, Institute of Public Health, University of Southern Denmark, Odense.,Department of Clinical Genetics, Odense University Hospital
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15
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Clinical Characteristics of Mitochondrial DNA Copy Number in Osteonecrosis of the Femoral Head. MEDICINA-LITHUANIA 2020; 56:medicina56050239. [PMID: 32429397 PMCID: PMC7279179 DOI: 10.3390/medicina56050239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/02/2020] [Accepted: 05/13/2020] [Indexed: 11/20/2022]
Abstract
Background and objectives: Alterations in mitochondrial DNA (mtDNA) have been observed and studied in various diseases. However, the clinical value of the mtDNA copy number (mtDNA-CN) alterations in osteonecrosis of the femoral head (ONFH) is poorly understood. In the present study, we investigated whether alterations in mtDNA-CNs are associated with clinicopathological parameters in ONFH. Materials and methods: MtDNA-CNs in the synovial tissue of 34 patients with ONFH and 123 control tissues (femoral neck fracture) were measured using quantitative real-time PCR. The present study then analyzed the correlation between the mtDNA-CN and the clinicopathological characteristics of ONFH and fracture patients. Results: The average mtDNA-CN (mean ± standard deviation) was 23.82 ± 22.37 and 25.04 ± 24.27 in ONFH and control tissues, respectively, and was not significantly different between the groups (p = 0.792). The mtDNA-CN was positively associated with age (27.7% vs. 45.9%, p = 0.018) and negatively associated with the erythrocyte sedimentation rate (ESR) (11.8% vs. 39.7%, p = 0.024) in all of the samples. The study also found further associations with age (22.2% vs. 68.8%, p = 0.014), gender (30.0% vs. 64.3%, p = 0.048), and ESR (0% vs. 57.7%, p = 0.043) in ONFH. Conclusions: in this study, we demonstrated that mtDNA-CN might be a significant marker for predicting clinical characteristics in ONFH.
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16
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Cosemans C, Nawrot TS, Janssen BG, Vriens A, Smeets K, Baeyens W, Bruckers L, Den Hond E, Loots I, Nelen V, Van Larebeke N, Schoeters G, Martens D, Plusquin M. Breastfeeding predicts blood mitochondrial DNA content in adolescents. Sci Rep 2020; 10:387. [PMID: 31941967 PMCID: PMC6962168 DOI: 10.1038/s41598-019-57276-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 12/19/2019] [Indexed: 02/06/2023] Open
Abstract
Nutrition during early childhood is linked to metabolic programming. We hypothesized that breastfeeding has long-term consequences on the energy metabolism exemplified by mitochondrial DNA (mtDNA). As part of the third cycle of the Flemish Environment and Health Study (FLEHSIII) cohort, 303 adolescents aged 14–15 years were included. We associated breastfeeding and blood mtDNA content 14–15 years later while adjusting for confounding variables. Compared with non-breastfed adolescents, mtDNA content was 23.1% (95%CI: 4.4–45.2; p = 0.013) higher in breastfed adolescents. Being breastfed for 1–10 weeks, 11–20 weeks, and >20 weeks, was associated with a higher mtDNA content of respectively 16.0% (95%CI: −7.1–44.9; p = 0.191), 23.5% (95%CI: 0.8–51.3; p = 0.042), and 31.5% (95%CI: 4.3–65.7; p = 0.021). Our study showed a positive association between breastfeeding and mtDNA content in adolescents which gradually increased with longer periods of breastfeeding. Higher mtDNA content may be an underlying mechanism of the beneficial effects of breastfeeding on children’s metabolism.
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Affiliation(s)
- Charlotte Cosemans
- Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium
| | - Tim S Nawrot
- Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium.,School of Public Health, Occupational & Environmental Medicine, Leuven University, Leuven, Belgium
| | - Bram G Janssen
- Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium
| | - Annette Vriens
- Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium
| | - Karen Smeets
- Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium
| | - Willy Baeyens
- Department of Analytical and Environmental Chemistry, Vrije Universiteit Brussel, Brussels, Belgium
| | - Liesbeth Bruckers
- Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, Hasselt, Belgium
| | | | - Ilse Loots
- Faculty of Social Sciences and IMDO-Institute, University of Antwerp, Antwerp, Belgium
| | - Vera Nelen
- Provincial Institute for Hygiene, Antwerp, Belgium
| | - Nicolas Van Larebeke
- Department of Radiotherapy and Experimental Cancerology, Ghent University, Ghent, Belgium.,Department of Analytical, Environmental and Geo-Chemistry, Vrije Universiteit Brussel, Brussels, Belgium
| | - Greet Schoeters
- Environmental Risk and Health, Flemish Institute for Technological Research (VITO), Mol, Belgium
| | - Dries Martens
- Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium
| | - Michelle Plusquin
- Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium.
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17
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Guyatt AL, Brennan RR, Burrows K, Guthrie PAI, Ascione R, Ring SM, Gaunt TR, Pyle A, Cordell HJ, Lawlor DA, Chinnery PF, Hudson G, Rodriguez S. A genome-wide association study of mitochondrial DNA copy number in two population-based cohorts. Hum Genomics 2019; 13:6. [PMID: 30704525 PMCID: PMC6357493 DOI: 10.1186/s40246-018-0190-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 12/27/2018] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Mitochondrial DNA copy number (mtDNA CN) exhibits interindividual and intercellular variation, but few genome-wide association studies (GWAS) of directly assayed mtDNA CN exist. We undertook a GWAS of qPCR-assayed mtDNA CN in the Avon Longitudinal Study of Parents and Children (ALSPAC) and the UK Blood Service (UKBS) cohort. After validating and harmonising data, 5461 ALSPAC mothers (16-43 years at mtDNA CN assay) and 1338 UKBS females (17-69 years) were included in a meta-analysis. Sensitivity analyses restricted to females with white cell-extracted DNA and adjusted for estimated or assayed cell proportions. Associations were also explored in ALSPAC children and UKBS males. RESULTS A neutrophil-associated locus approached genome-wide significance (rs709591 [MED24], β (change in SD units of mtDNA CN per allele) [SE] - 0.084 [0.016], p = 1.54e-07) in the main meta-analysis of adult females. This association was concordant in magnitude and direction in UKBS males and ALSPAC neonates. SNPs in and around ABHD8 were associated with mtDNA CN in ALSPAC neonates (rs10424198, β [SE] 0.262 [0.034], p = 1.40e-14), but not other study groups. In a meta-analysis of unrelated individuals (N = 11,253), we replicated a published association in TFAM (β [SE] 0.046 [0.017], p = 0.006), with an effect size much smaller than that observed in the replication analysis of a previous in silico GWAS. CONCLUSIONS In a hypothesis-generating GWAS, we confirm an association between TFAM and mtDNA CN and present putative loci requiring replication in much larger samples. We discuss the limitations of our work, in terms of measurement error and cellular heterogeneity, and highlight the need for larger studies to better understand nuclear genomic control of mtDNA copy number.
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Affiliation(s)
- Anna L. Guyatt
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Rebecca R. Brennan
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle, UK
- Institute of Genetic Medicine, Newcastle University, Newcastle, UK
| | - Kimberley Burrows
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Philip A. I. Guthrie
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Raimondo Ascione
- Bristol Heart Institute, Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Susan M. Ring
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Tom R. Gaunt
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Angela Pyle
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle, UK
| | | | - Debbie A. Lawlor
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Patrick F. Chinnery
- Department of Clinical Neurosciences and MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Gavin Hudson
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle, UK
- Institute of Genetic Medicine, Newcastle University, Newcastle, UK
| | - Santiago Rodriguez
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
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18
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Abstract
Mitochondria are essential intracellular organelles that are responsible for energy metabolism, cell growth, and differentiation, redox homeostasis, oncogenic signaling, and apoptosis. These multifunctional organelles have been implicated in cancer initiation, progression, and metastasis, relapse, and acquired drug resistance due to metabolic alterations in transformed cells. Maternally inherited mitochondrial DNA (mtDNA) is thought to contribute to cancer development and prognosis and proposed as a therapeutic target for cancer treatment. In this review, we summarize the current knowledge of mtDNA alterations, with a specific focus on somatic changes, germline variants, haplogroups, large deletions, and mtDNA content changes associated with cancer susceptibility and prognosis. We also discuss the potential of mtDNA as biomarkers of cancer detection and targets of cancer treatment. Deeper understanding of the mechanisms underlying these associations requires further investigation.
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19
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Li Z, Zhu M, Du J, Ma H, Jin G, Dai J. Genetic variants in nuclear DNA along with environmental factors modify mitochondrial DNA copy number: a population-based exome-wide association study. BMC Genomics 2018; 19:752. [PMID: 30326835 PMCID: PMC6192277 DOI: 10.1186/s12864-018-5142-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Accepted: 10/05/2018] [Indexed: 12/24/2022] Open
Abstract
Background Mitochondrial DNA (mtDNA) copy number has been found associated with multiple diseases, including cancers, diabetes and so on. Both environmental and genetic factors could affect the copy number of mtDNA. However, limited study was available about the relationship between genetic variants and mtDNA copy number. What’s more, most of previous studies considered only environmental or genetic factors. Therefore, it’s necessary to explore the genetic effects on mtDNA copy number with the consideration of PM2.5 exposure and smoking. Results A multi-center population-based study was performed with 301 subjects from Zhuhai, Wuhan and Tianjin. Personal 24-h PM2.5 exposure levels, smoking and mtDNA copy number were evaluated. The Illumina Human Exome BeadChip, which contained 241,305 single nucleotide variants, was used for genotyping. The association analysis was conducted in each city and meta-analysis was adopted to combine the overall effect among three cities. Seven SNPs showed significant association with mtDNA copy number with P value less than 1.00E-04 after meta-analysis. The following joint analysis of our identified SNPs showed a significant allele-dosage association between the number of variants and mtDNA copy number (P = 5.02 × 10− 17). Further, 11 genes were identified associated with mtDNA copy number using gene-based analysis with a P value less than 0.01. Conclusion This study was the first attempt to evaluate the genetic effects on mtDNA copy number with the consideration of personal PM2.5 exposure level. Our findings could provide more evidences that genetic variants played important roles in modulating the copy number of mtDNA. Electronic supplementary material The online version of this article (10.1186/s12864-018-5142-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zhihua Li
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, Jiangsu, China.,Department of Thoracic Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Meng Zhu
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, Jiangsu, China
| | - Jiangbo Du
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, Jiangsu, China
| | - Hongxia Ma
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, Jiangsu, China.,Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, 211166, Jiangsu, China
| | - Guangfu Jin
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, Jiangsu, China.,Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, 211166, Jiangsu, China
| | - Juncheng Dai
- Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, Jiangsu, China. .,Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, 211166, Jiangsu, China.
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20
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Svendsen AJ, Tan Q, Jakobsen MA, Thyagarajan B, Nygaard M, Christiansen L, Mengel-From J. White blood cell mitochondrial DNA copy number is decreased in rheumatoid arthritis and linked with risk factors. A twin study. J Autoimmun 2018; 96:142-146. [PMID: 30327147 DOI: 10.1016/j.jaut.2018.09.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/19/2018] [Accepted: 09/21/2018] [Indexed: 01/10/2023]
Abstract
Low mitochondrial DNA copy number (mtDNA CN) has been associated with e.g. cancer, cardiovascular and autoimmune diseases. We aimed to study a potential association between mtDNA CN and rheumatoid arthritis (RA). The relative quantity of mitochondrial DNA compared to nuclear DNA was measured in peripheral white blood cells from 149 RA affected twin pairs and 1321 non-affected twin pairs. Multiple regression analysis including RA discordant twin pairs was performed in order to separate specific effects of RA and familial RA predisposition using non-RA affected twin pairs as reference group. In addition, we performed a twin pair level analysis including only RA discordant twin pairs evaluating the effect of cell type, auto antibodies and RA genetic risk factors. Both the RA twins and their non-affected co-twins had significantly lower mtDNA CN than non-affected twins (-28.7 and -23.1 mtDNA CN, respectively). Adjusting for cell count attenuated these differences (-23.1 mtDNA CN and -20.1 mtDNA CN respectively). Within RA discordant twin pairs PTPN22(T) positive RA twins had a significantly lower amount than their co-twins (-16.3 mtDNA CN). PTPN22(T) had no effect among twins from non-affected twin pairs. MtDNA CN is significantly lower in persons with established RA and in predisposed non-affected RA co-twins suggesting that mitochondrial variation may be involved in the RA disease pathways. Our results also suggest that the RA associated genetic risk factor, PTPN22(T), further decreases the mtDNA CN, but only in carriers with established RA.
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Affiliation(s)
- Anders J Svendsen
- Department of Internal Medicine, Odense University Hospital, Svendborg, Denmark; Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, Odense, Denmark
| | - Qihua Tan
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, Odense, Denmark; Unit of Human Genetics, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Marianne A Jakobsen
- Department of Clinical Immunology, Odense University Hospital, Odense, Denmark
| | - Bharat Thyagarajan
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, USA
| | - Marianne Nygaard
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, Odense, Denmark
| | - Lene Christiansen
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, Odense, Denmark; Unit of Human Genetics, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Jonas Mengel-From
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, Odense, Denmark; Unit of Human Genetics, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
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Aberrant telomere length and mitochondrial DNA copy number in suicide completers. Sci Rep 2017; 7:3176. [PMID: 28600518 PMCID: PMC5466636 DOI: 10.1038/s41598-017-03599-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 05/02/2017] [Indexed: 11/16/2022] Open
Abstract
Short telomere length (TL) occurs in individuals under psychological stress, and with various psychiatric diseases. Recent studies have also reported mitochondrial DNA copy number (mtDNAcn) alterations under several neuropsychiatric conditions. However, no study has examined whether aberrant TL or mtDNAcn occur in completed suicide, one of the most serious outcomes of mental illnesses. TL and mtDNAcn in post-mortem samples from 528 suicide completers without severe physical illness (508 peripheral bloods; 20 brains) and 560 samples from control subjects (peripheral bloods from 535 healthy individuals; 25 post-mortem brains) were analysed by quantitative polymerase chain reaction. Suicide completers had significantly shorter TL and higher mtDNAcn of peripheral bloods with sex/age-dependent differences (shorter TL was more remarkably in female/young suicides; higher mtDNAcn more so in male/elderly suicides). The normal age-related decline of TL and mtDNAcn were significantly altered in suicide completers. Furthermore, shorter TL and lower mtDNAcn of post-mortem prefrontal cortex were seen in suicide completers compared to controls. This study shows the first association of aberrant telomeres and mtDNA content with suicide completion. Our results indicate that further research on telomere shortening and mitochondrial dysfunction may help elucidate the molecular underpinnings of suicide-related pathophysiology.
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Reverter A, Okimoto R, Sapp R, Bottje WG, Hawken R, Hudson NJ. Chicken muscle mitochondrial content appears co-ordinately regulated and is associated with performance phenotypes. Biol Open 2017; 6:50-58. [PMID: 27934661 PMCID: PMC5278435 DOI: 10.1242/bio.022772] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Mitochondrial content is a fundamental cellular bioenergetic phenotype. Previous work has hypothesised possible links between variation in muscle mitochondrial content and animal performance. However, no population screens have been performed in any production species. Here, we have designed a high throughput molecular approach to estimate mitochondrial content in commercial broilers. Technical validity was established using several approaches, including its performance in monoclonal DF-1 cells, cross-tissue comparisons in tissues with differing metabolic demands (white fat<breast muscle<drumstick muscle<heart muscle) and, as a negative control, a near absence of mtDNA amplification from whole blood. We screened breast muscle and thigh muscle in 80 birds individually phenotyped for 11 growth and development traits. Substantial individual variation (fivefold) was discovered in both breast and thigh muscle mitochondrial content. Interestingly, across birds we detected a very strong positive relationship between breast and thigh content (correlation coefficient 0.61; P<0.0001), consistent with coordinate regulatory control across the musculature. Further, breast muscle mitochondrial content is negatively correlated with breast muscle yield (−0.27; P=0.037), abdominal fat content (−0.31; P=0.017) and carcass yield (−0.26; P=0.045). Therefore, low breast muscle mitochondrial content is associated with more muscular birds possessing higher abdominal fat, the latter being in line with biomedical models of obesity. Finally, thigh mitochondrial content is negatively correlated with the bow out leg defect (−0.30; P=0.011). Overall, our data point to mitochondrial content as a promising consideration in predictive modelling of production traits. Summary: We have detected variation in muscle mitochondrial content across chickens. This variation relates to phenotypes and also indicates coordinate regulation of mitochondrial biogenesis across the musculature.
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Affiliation(s)
- Antonio Reverter
- Agriculture and Food, Commonwealth Science and Industrial Research Organisation, Brisbane, Queensland 4067, Australia
| | - Ron Okimoto
- Cobb-Vantress Inc., US-412, Siloam Springs, AR 72761, USA
| | - Robyn Sapp
- Cobb-Vantress Inc., US-412, Siloam Springs, AR 72761, USA
| | - Walter G Bottje
- Department of Poultry Science, University of Arkansas, Fayetteville, AR, USA
| | - Rachel Hawken
- Cobb-Vantress Inc., US-412, Siloam Springs, AR 72761, USA
| | - Nicholas J Hudson
- School of Agriculture and Food Science, University of Queensland, Building 8117A, Gatton, Queensland 4343, Australia
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Peripheral Blood Mitochondrial DNA and Myocardial Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 982:347-358. [DOI: 10.1007/978-3-319-55330-6_19] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Knez J, Winckelmans E, Plusquin M, Thijs L, Cauwenberghs N, Gu Y, Staessen JA, Nawrot TS, Kuznetsova T. Correlates of Peripheral Blood Mitochondrial DNA Content in a General Population. Am J Epidemiol 2016; 183:138-46. [PMID: 26702630 PMCID: PMC4706678 DOI: 10.1093/aje/kwv175] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 06/24/2015] [Indexed: 12/19/2022] Open
Abstract
Accumulation of mitochondrial DNA (mtDNA) mutations leads to alterations of mitochondrial biogenesis and function that might produce a decrease in mtDNA content within cells. This implies that mtDNA content might be a potential biomarker associated with oxidative stress and inflammation. However, data on correlates of mtDNA content in a general population are sparse. Our goal in the present study was to describe in a randomly recruited population sample the distribution and determinants of peripheral blood mtDNA content. From 2009 to 2013, we examined 689 persons (50.4% women; mean age = 54.4 years) randomly selected from a Flemish population (Flemish Study on Environment, Genes, and Health Outcomes). Relative mtDNA copy number as compared with nuclear DNA was measured by quantitative real-time polymerase chain reaction in peripheral blood. There was a curvilinear relationship between relative mtDNA copy number and age. mtDNA content slightly increased until the fifth decade of life and declined in older subjects (Page2 = 0.0002). mtDNA content was significantly higher in women (P = 0.007) and increased with platelet count (P < 0.0001), whereas it was inversely associated with white blood cell count (P < 0.0001). We also observed lower mtDNA content in women using estroprogestogens (P = 0.044). This study demonstrated in a general population that peripheral blood mtDNA content is significantly associated with sex and age. Blood mtDNA content is also influenced by platelet and white blood cell counts and estroprogestogen intake. Further studies are required to clarify the impact of chronic inflammation and hormone therapy on mitochondrial function.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Tatiana Kuznetsova
- Correspondence to Dr. Tatiana Kuznetsova, Hypertension and Cardiovascular Epidemiology Research Unit, Department of Cardiovascular Sciences, Biomedical Sciences Group, University of Leuven, Campus Sint Rafaël, Kapucijnenvoer 35, Box 7001, B 3000 Leuven, Belgium (e-mail: )
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Stier A, Reichert S, Criscuolo F, Bize P. Red blood cells open promising avenues for longitudinal studies of ageing in laboratory, non-model and wild animals. Exp Gerontol 2015; 71:118-34. [DOI: 10.1016/j.exger.2015.09.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 09/01/2015] [Accepted: 09/02/2015] [Indexed: 12/12/2022]
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26
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Andalib S, Talebi M, Sakhinia E, Farhoudi M, Sadeghi-Bazargani H, Gjedde A. Lack of association between mitochondrial DNA G15257A and G15812A variations and multiple sclerosis. J Neurol Sci 2015; 356:102-6. [DOI: 10.1016/j.jns.2015.06.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 06/05/2015] [Accepted: 06/11/2015] [Indexed: 12/19/2022]
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28
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Qu F, Chen Y, Wang X, He X, Ren T, Huang Q, Zhang J, Liu X, Guo X, Gu J, Xing J. Leukocyte mitochondrial DNA content: a novel biomarker associated with prognosis and therapeutic outcome in colorectal cancer. Carcinogenesis 2015; 36:543-52. [PMID: 25823896 DOI: 10.1093/carcin/bgv042] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Compelling evidence has indicated a significant association between leukocyte mitochondrial DNA (mtDNA) content and incidence risks of several malignancies in a cancer-specific manner. However, to date, whether leukocyte mtDNA content can predict clinical outcome of cancer patients has never been investigated. In the present study, we measured leukocyte mtDNA content using real-time PCR-based method in a total of 598 colorectal cancer (CRC) patients and explored its prognostic values. To explore potential mechanism, we detected the immunophenotypes of peripheral blood mononuclear cells and plasma concentrations of several cytokines in CRC patients. We found that patients with high mtDNA content showed significantly worse overall survival (OS) and relapse-free survival (RFS) than those with low mtDNA content in all patient sets. Furthermore, mtDNA content and tumor node metastasis (TNM) stage exhibited a notable joint effect in prognosis prediction. Integration of TNM stage and leukocyte mtDNA content significantly improved the prognosis prediction efficacy for CRC. Importantly, patients with high mtDNA content showed OS and RFS benefits from adjuvant chemotherapy. In addition, we found that patients with high mtDNA content had a higher frequency of CD4(+)CD25(+)FOXP3(+) regulatory T cells, higher plasma interleukin-2 and transforming growth factor-β1 and lower tumor necrosis factor-α concentration than those with low mtDNA content, suggesting a stronger immunosuppressive phenotype. In conclusion, our study for the first time demonstrates that leukocyte mtDNA content is an independent prognostic marker complementing TNM stage and associated with immunosuppression in CRC patients. Additionally, leukocyte mtDNA content might serve as a potential biomarker to select CRC patients who will benefit from adjuvant chemotherapy.
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Affiliation(s)
- Falin Qu
- State Key Laboratory of Cancer Biology, Experimental Teaching Center of Basic Medicine, Department of General Surgery, Tangdu Hospital and
| | - Yibing Chen
- State Key Laboratory of Cancer Biology, Experimental Teaching Center of Basic Medicine
| | - Xin Wang
- State Key Laboratory of Cancer Biology, Experimental Teaching Center of Basic Medicine
| | - Xianli He
- Department of General Surgery, Tangdu Hospital and
| | - Tingting Ren
- State Key Laboratory of Cancer Biology, Experimental Teaching Center of Basic Medicine
| | - Qichao Huang
- State Key Laboratory of Cancer Biology, Experimental Teaching Center of Basic Medicine
| | - Jing Zhang
- State Key Laboratory of Cancer Biology, Experimental Teaching Center of Basic Medicine
| | - Xiaonan Liu
- Xijing Hospital of Digestive Disease, The Fourth Military Medical University, 169 West Changle Road, Xi'an 710032, China and
| | - Xu Guo
- State Key Laboratory of Cancer Biology, Experimental Teaching Center of Basic Medicine
| | - Jian Gu
- Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Jinliang Xing
- State Key Laboratory of Cancer Biology, Experimental Teaching Center of Basic Medicine,
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Chen S, Xie X, Wang Y, Gao Y, Xie X, Yang J, Ye J. Association between leukocyte mitochondrial DNA content and risk of coronary heart disease: A case-control study. Atherosclerosis 2014; 237:220-6. [DOI: 10.1016/j.atherosclerosis.2014.08.051] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 08/05/2014] [Accepted: 08/25/2014] [Indexed: 01/04/2023]
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30
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López S, Buil A, Souto JC, Casademont J, Martinez-Perez A, Almasy L, Soria JM. A genome-wide association study in the genetic analysis of idiopathic thrombophilia project suggests sex-specific regulation of mitochondrial DNA levels. Mitochondrion 2014; 18:34-40. [PMID: 25240745 DOI: 10.1016/j.mito.2014.09.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 08/24/2014] [Accepted: 09/10/2014] [Indexed: 12/20/2022]
Abstract
Identifying genes that regulate mitochondrial DNA (mtDNA) levels is of interest due to an increasing number of diseases in humans that are associated with altered mtDNA levels. We searched for nuclear polymorphisms that influence mtDNA levels using a family-based genome-wide association (GWAS) method. Also, our aim was to determine if sex influences the genetic control of mtDNA levels. Two intron-polymorphisms, in the genes PARK2 and MRPL37, showed a tendency toward an association with mtDNA levels only in females and only in males, respectively. Both genes have a role in mitochondrial biogenesis and are potential candidates for the sex-specific control of mtDNA levels.
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Affiliation(s)
- Sonia López
- Unit of Genomic of Complex Diseases, Research Institute of Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
| | - Alfonso Buil
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | - Juan Carlos Souto
- Haemostasis and Thrombosis Unit, Department of Haematology, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Jordi Casademont
- Internal Medicine Department, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Angel Martinez-Perez
- Unit of Genomic of Complex Diseases, Research Institute of Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Laura Almasy
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - José Manuel Soria
- Unit of Genomic of Complex Diseases, Research Institute of Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
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31
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Mengel-From J, Thinggaard M, Dalgård C, Kyvik KO, Christensen K, Christiansen L. Mitochondrial DNA copy number in peripheral blood cells declines with age and is associated with general health among elderly. Hum Genet 2014; 133:1149-59. [PMID: 24902542 DOI: 10.1007/s00439-014-1458-9] [Citation(s) in RCA: 244] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Accepted: 05/22/2014] [Indexed: 12/21/2022]
Abstract
The role of the mitochondria in disease, general health and aging has drawn much attention over the years. Several attempts have been made to describe how the numbers of mitochondria correlate with age, although with inconclusive results. In this study, the relative quantity of mitochondrial DNA compared to nuclear DNA, i.e. the mitochondrial DNA copy number, was measured by PCR technology and used as a proxy for the content of mitochondria copies. In 1,067 Danish twins and singletons (18-93 years of age), with the majority being elderly individuals, the estimated mean mitochondrial DNA copy number in peripheral blood cells was similar for those 18-48 years of age [mean relative mtDNA content: 61.0; 95 % CI (52.1; 69.9)], but declined by -0.54 mtDNA 95 % CI (-0.63; -0.45) every year for those older than approximately 50 years of age. However, the longitudinal, yearly decline within an individual was more than twice as steep as observed in the cross-sectional analysis [decline of mtDNA content: -1.27; 95 % CI (-1.71; -0.82)]. Subjects with low mitochondrial DNA copy number had poorer outcomes in terms of cognitive performance, physical strength, self-rated health, and higher all-cause mortality than subjects with high mitochondrial DNA copy number, also when age was controlled for. The copy number mortality association can contribute to the smaller decline in a cross-sectional sample of the population compared to the individual, longitudinal decline. This study suggests that high mitochondrial DNA copy number in blood is associated with better health and survival among elderly.
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Affiliation(s)
- Jonas Mengel-From
- Epidemiology, Biostatistics and Biodemography Unit, The Danish Aging Research Center, The Danish Twin Registry, Institute of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9, 5000, Odense, Denmark,
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He Y, Tang J, Li Z, Li H, Liao Y, Tang Y, Tan L, Chen J, Xia K, Chen X. Leukocyte mitochondrial DNA copy number in blood is not associated with major depressive disorder in young adults. PLoS One 2014; 9:e96869. [PMID: 24809340 PMCID: PMC4014566 DOI: 10.1371/journal.pone.0096869] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 04/12/2014] [Indexed: 01/02/2023] Open
Abstract
Background Major depressive disorder (MDD) is the leading cause of disability worldwide, and has significant genetic predisposition. Mitochondria may have a role in MDD and so mitochondrial DNA (mtDNA) has been suggested as a possible biomarker for this disease. We aimed to test whether the mtDNA copy number of peripheral blood leukocytes is related to MDD in young adults. Methods A case-control study was conducted with 210 MDD patients and 217 healthy controls (HC). The mtDNA copy number was measured by quantitative polymerase chain reaction (qPCR) method. Depression severity was assessed by the Hamilton-17 Depression Rating Scale (HDRS-17). Results We found no significant differences in mtDNA copy number between MDD patients and HC, though the power analysis showed that our sample size has enough power to detect the difference. There were also no significant correlations between mtDNA copy number and the clinical characteristics (such as age, age of onset, episodes, Hamilton Depression Rating Scale (HDRS) score and Global Assessment of Function Scale (GAF) score) in MDD patients. Conclusion Our study suggests that leukocyte mtDNA copy number is unlikely to contribute to MDD, but it doesn’t mean that we can exclude the possibility of involvement of mitochondria in the disease. Further studies are required to elucidate whether mtDNA can be a biomarker of MDD.
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Affiliation(s)
- Ying He
- Institute of Mental Health, the Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Jinsong Tang
- Institute of Mental Health, the Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Zongchang Li
- Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Hong Li
- Institute of Mental Health, the Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Yanhui Liao
- Institute of Mental Health, the Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Yanqing Tang
- Department of Psychiatry, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, China
| | - Liwen Tan
- Institute of Mental Health, the Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Jindong Chen
- Institute of Mental Health, the Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Kun Xia
- The State Key Laboratory of Medical Genetics, Central South University, Changsha, Hunan, China
| | - Xiaogang Chen
- Institute of Mental Health, the Second Xiangya Hospital of Central South University, Changsha, Hunan, China; The State Key Laboratory of Medical Genetics, Central South University, Changsha, Hunan, China; Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan, China; The State Key Laboratory of Medical Genetics, Central South University, Changsha, Hunan, China
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Giordano C, Iommarini L, Giordano L, Maresca A, Pisano A, Valentino ML, Caporali L, Liguori R, Deceglie S, Roberti M, Fanelli F, Fracasso F, Ross-Cisneros FN, D’Adamo P, Hudson G, Pyle A, Yu-Wai-Man P, Chinnery PF, Zeviani M, Salomao SR, Berezovsky A, Belfort R, Ventura DF, Moraes M, Moraes Filho M, Barboni P, Sadun F, De Negri A, Sadun AA, Tancredi A, Mancini M, d’Amati G, Loguercio Polosa P, Cantatore P, Carelli V. Efficient mitochondrial biogenesis drives incomplete penetrance in Leber's hereditary optic neuropathy. Brain 2014; 137:335-53. [PMID: 24369379 PMCID: PMC3914475 DOI: 10.1093/brain/awt343] [Citation(s) in RCA: 200] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Revised: 09/06/2013] [Accepted: 10/21/2013] [Indexed: 12/16/2022] Open
Abstract
Leber's hereditary optic neuropathy is a maternally inherited blinding disease caused as a result of homoplasmic point mutations in complex I subunit genes of mitochondrial DNA. It is characterized by incomplete penetrance, as only some mutation carriers become affected. Thus, the mitochondrial DNA mutation is necessary but not sufficient to cause optic neuropathy. Environmental triggers and genetic modifying factors have been considered to explain its variable penetrance. We measured the mitochondrial DNA copy number and mitochondrial mass indicators in blood cells from affected and carrier individuals, screening three large pedigrees and 39 independently collected smaller families with Leber's hereditary optic neuropathy, as well as muscle biopsies and cells isolated by laser capturing from post-mortem specimens of retina and optic nerves, the latter being the disease targets. We show that unaffected mutation carriers have a significantly higher mitochondrial DNA copy number and mitochondrial mass compared with their affected relatives and control individuals. Comparative studies of fibroblasts from affected, carriers and controls, under different paradigms of metabolic demand, show that carriers display the highest capacity for activating mitochondrial biogenesis. Therefore we postulate that the increased mitochondrial biogenesis in carriers may overcome some of the pathogenic effect of mitochondrial DNA mutations. Screening of a few selected genetic variants in candidate genes involved in mitochondrial biogenesis failed to reveal any significant association. Our study provides a valuable mechanism to explain variability of penetrance in Leber's hereditary optic neuropathy and clues for high throughput genetic screening to identify the nuclear modifying gene(s), opening an avenue to develop predictive genetic tests on disease risk and therapeutic strategies.
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Affiliation(s)
- Carla Giordano
- 1 Department of Radiology, Oncology and Pathology, Sapienza, University of Rome, Rome, Italy
| | - Luisa Iommarini
- 2 Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
| | - Luca Giordano
- 3 Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Alessandra Maresca
- 2 Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
- 4 IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, Bologna, Italy
| | - Annalinda Pisano
- 1 Department of Radiology, Oncology and Pathology, Sapienza, University of Rome, Rome, Italy
| | - Maria Lucia Valentino
- 2 Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
- 4 IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, Bologna, Italy
| | - Leonardo Caporali
- 2 Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
- 4 IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, Bologna, Italy
| | - Rocco Liguori
- 2 Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
- 4 IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, Bologna, Italy
| | - Stefania Deceglie
- 3 Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Marina Roberti
- 3 Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Francesca Fanelli
- 3 Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Flavio Fracasso
- 3 Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Fred N. Ross-Cisneros
- 5 Departments of Ophthalmology and Neurosurgery, Keck School of Medicine at USC, Los Angeles, CA, USA
| | - Pio D’Adamo
- 6 Medical Genetics, Department of Reproductive Sciences, Development and Public Health
- 7 IRCCS-Burlo Garofolo Children Hospital, University of Trieste, Trieste, Italy
| | - Gavin Hudson
- 8 Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Angela Pyle
- 8 Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Patrick Yu-Wai-Man
- 8 Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Patrick F. Chinnery
- 8 Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Massimo Zeviani
- 9 Unit of Molecular Neurogenetics, Fondazione Istituto Neurologico “Carlo Besta” - IRCCS, Milano, Italy
- 10 MRC-Mitochondrial Biology Unit, Cambridge, UK
| | - Solange R. Salomao
- 11 Department of Ophthalmology, Federal University of Sao Paulo – UNIFESP, Sao Paulo, Brazil
| | - Adriana Berezovsky
- 11 Department of Ophthalmology, Federal University of Sao Paulo – UNIFESP, Sao Paulo, Brazil
| | - Rubens Belfort
- 11 Department of Ophthalmology, Federal University of Sao Paulo – UNIFESP, Sao Paulo, Brazil
| | - Dora Fix Ventura
- 12 Department of Experimental Psychology, Institute of Psychology, University of Sao Paulo, Sao Paulo, Brazil
| | - Milton Moraes
- 11 Department of Ophthalmology, Federal University of Sao Paulo – UNIFESP, Sao Paulo, Brazil
| | - Milton Moraes Filho
- 11 Department of Ophthalmology, Federal University of Sao Paulo – UNIFESP, Sao Paulo, Brazil
| | | | | | | | - Alfredo A. Sadun
- 5 Departments of Ophthalmology and Neurosurgery, Keck School of Medicine at USC, Los Angeles, CA, USA
| | - Andrea Tancredi
- 16 Dipartimento di Metodi e Modelli per l’Economia la Finanza e il Territorio, Sapienza, Università di Roma, Roma, Italy
| | - Massimiliano Mancini
- 1 Department of Radiology, Oncology and Pathology, Sapienza, University of Rome, Rome, Italy
- 17 Department of Molecular Medicine, Sapienza, University of Rome
| | - Giulia d’Amati
- 1 Department of Radiology, Oncology and Pathology, Sapienza, University of Rome, Rome, Italy
| | - Paola Loguercio Polosa
- 3 Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Palmiro Cantatore
- 3 Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Valerio Carelli
- 2 Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
- 4 IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, Bologna, Italy
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Motamed M, Rajapakshe KI, Hartig SM, Coarfa C, Moses RE, Lonard DM, O'Malley BW. Steroid receptor coactivator 1 is an integrator of glucose and NAD+/NADH homeostasis. Mol Endocrinol 2014; 28:395-405. [PMID: 24438340 DOI: 10.1210/me.2013-1404] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Steroid receptor coactivator 1 (SRC-1) drives diverse gene expression programs necessary for the dynamic regulation of cancer metastasis, inflammation and gluconeogenesis, pointing to its overlapping roles as an oncoprotein and integrator of cell metabolic programs. Nutrient utilization has been intensely studied with regard to cellular adaptation in both cancer and noncancerous cells. Nonproliferating cells consume glucose through the citric acid cycle to generate NADH to fuel ATP generation via mitochondrial oxidative phosphorylation. In contrast, cancer cells undergo metabolic reprogramming to support rapid proliferation. To generate lipids, nucleotides, and proteins necessary for cell division, most tumors switch from oxidative phosphorylation to glycolysis, a phenomenon known as the Warburg Effect. Because SRC-1 is a key coactivator responsible for driving a hepatic gluconeogenic program under fasting conditions, we asked whether SRC-1 responds to alterations in nutrient availability to allow for adaptive metabolism. Here we show SRC-1 is stabilized by the 26S proteasome in the absence of glucose. RNA profiling was used to examine the effects of SRC-1 perturbation on gene expression in the absence or presence of glucose, revealing that SRC-1 affects the expression of complex I of the mitochondrial electron transport chain, a set of enzymes responsible for the conversion of NADH to NAD(+). NAD(+) and NADH were subsequently identified as metabolites that underlie SRC-1's response to glucose deprivation. Knockdown of SRC-1 in glycolytic cancer cells abrogated their ability to grow in the absence of glucose consistent with SRC-1's role in promoting cellular adaptation to reduced glucose availability.
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Affiliation(s)
- Massoud Motamed
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030
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Andalib S, Talebi M, Sakhinia E, Farhoudi M, Sadeghi-Bazargani H, Motavallian A, Pilehvar-Soltanahmadi Y. Multiple sclerosis and mitochondrial gene variations: a review. J Neurol Sci 2013; 330:10-5. [PMID: 23669867 DOI: 10.1016/j.jns.2013.04.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2013] [Revised: 04/16/2013] [Accepted: 04/18/2013] [Indexed: 01/07/2023]
Abstract
Multiple sclerosis (MS) is a debilitating disease of the central nervous system. Its etiology is still an unanswered enigma; its symptoms are varied and unpredictable; and there is no cure for it. Genetics has been introduced as a contributing factor to MS. Not only may MS stem from nuclear gene variations/mutations, but also it may arise from mitochondrial gene variations/mutations. The association of mitochondrial DNA variations/mutations with the pathogenesis of MS has, so far, been analyzed by several studies. This paper reviews the literature with regard to MS and corresponding mitochondrial DNA variations.
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Affiliation(s)
- Sasan Andalib
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
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López S, Buil A, Souto JC, Casademont J, Blangero J, Martinez-Perez A, Fontcuberta J, Lathrop M, Almasy L, Soria JM. Sex-specific regulation of mitochondrial DNA levels: genome-wide linkage analysis to identify quantitative trait loci. PLoS One 2012; 7:e42711. [PMID: 22916149 PMCID: PMC3423410 DOI: 10.1371/journal.pone.0042711] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2012] [Accepted: 07/10/2012] [Indexed: 01/27/2023] Open
Abstract
Altered mitochondrial DNA (mtDNA) levels have been associated with common diseases in humans. We investigated the genetic mechanism that controls mtDNA levels using genome-wide linkage analyses in families from the Genetic Analysis of Idiopathic Thrombophilia Project (GAIT). We measure mtDNA levels by quantitative real-time PCR in 386 subjects from 21 extended Spanish families. A variance component linkage method using 485 microsatellites was conducted to evaluate linkage and to detect quantitative trait loci (QTLs) involved in the control of mtDNA levels. The heritalibility of mtDNA levels was 0.33 (p=1.82e-05). We identified a QTL on Chromosome 2 (LOD=2.21) using all of the subjects, independently on their sex. When females and males were analysed separately, three QTLs were identified. Females showed the same QTL on Chromosome 2 (LOD=3.09), indicating that the QTL identified in the analysis using all of the subjects was a strong female QTL, and another one on Chromosome 3 (LOD=2.67), whereas in males a QTL was identified on Chromosome 1 (LOD=2.81). These QTLs were fine-mapped to find associations with mtDNA levels. The most significant SNP association was for the rs10888838 on Chromosome 1 in males. This SNP mapped to the gene MRPL37, involved in mitochondrial protein translation. The rs2140855 on Chromosome 2 showed association in the analysis using all of the subjects. It was near the gene CMPK2, which encodes a mitochondrial enzyme of the salvage pathway of deoxyribonucleotide synthesis. Our results provide evidence of a sex-specific genetic mechanism for the control of mtDNA levels and provide a framework to identify new genes that influence mtDNA levels.
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Affiliation(s)
- Sonia López
- Unit of Genomic of Complex Diseases, Institute of Biomedical Research of Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Alfonso Buil
- Unit of Genomic of Complex Diseases, Institute of Biomedical Research of Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Juan Carlos Souto
- Haemostasis and Thrombosis Unit, Department of Haematology, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Jordi Casademont
- Internal Medicine Department, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - John Blangero
- Department of Population Genetics, Texas Biomedical Research Institute, San Antonio, Texas, United States of America
| | - Angel Martinez-Perez
- Unit of Genomic of Complex Diseases, Institute of Biomedical Research of Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Jordi Fontcuberta
- Haemostasis and Thrombosis Unit, Department of Haematology, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Mark Lathrop
- Institut de Génomique, Centre National de Génotypage, Evry, France
| | - Laura Almasy
- Department of Population Genetics, Texas Biomedical Research Institute, San Antonio, Texas, United States of America
| | - Jose Manuel Soria
- Unit of Genomic of Complex Diseases, Institute of Biomedical Research of Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
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Xu FX, Zhou X, Shen F, Pang R, Liu SM. Decreased peripheral blood mitochondrial DNA content is related to HbA1c, fasting plasma glucose level and age of onset in type 2 diabetes mellitus. Diabet Med 2012; 29:e47-54. [PMID: 22211946 DOI: 10.1111/j.1464-5491.2011.03565.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS Mitochondrial DNA (mtDNA) content is essential for maintaining normal mitochondrial function, and the mitochondrial function is critical for the production and the release of insulin in Type 2 diabetes mellitus. We investigated whether peripheral blood mtDNA content was reduced in Type 2 diabetes, and what were the major factors? METHODS The mtDNA content of peripheral blood in a sample of 147 Type 2 diabetes and 170 normal Chinese subjects was determined by amplification of the mitochondrial gene CYT-B and normalized by a nuclear DNA β-globin gene. Fasting plasma glucose, HbA(1c) , fasting plasma insulin and lipid profile (HDL-cholesterol, LDL-cholesterol, total cholesterol, triglyceride) were analysed with commercial kits on an automatic analyser. RESULTS In Type 2 diabetes group, the mean HbA(1c) was 62 mmol/mol (7.8%). Moreover, BMI, systolic blood pressure, diastolic blood pressure, fasting plasma glucose, LDL-cholesterol, triglyceride, fasting plasma insulin and homeostasis model assessment for insulin resistance were significantly higher in Type 2 diabetes group than that in control group. Peripheral blood mtDNA content was 24% lower than that in the controls (1.4 ± 0.5 vs. 1.8 ± 0.7, P < 0.001). The mtDNA content was negatively correlated with BMI, fasting plasma glucose, fasting plasma insulin, homeostasis model assessment for insulin resistance (P < 0.01), and age, triglyceride and LDL-cholesterol levels (P < 0.05); while positively correlated with HDL-cholesterol level (P < 0.05) in both groups. Stepwise regression analysis indicated that HbA(1c), fasting plasma glucose and age of onset were the major factors affecting the mtDNA content in the Type 2 diabetes group; however, BMI was the only variable associated with lower mtDNA content in control group. CONCLUSION Our results demonstrate that lower peripheral blood mtDNA content is associated with Type 2 diabetes in Chinese individuals, and HbA(1c), fasting plasma glucose and age of onset are the major factors affecting the mtDNA content.
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Affiliation(s)
- F X Xu
- Center for Gene Diagnosis, Zhongnan Hospital, Wuhan University, Wuhan, China
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Point-of-care capillary blood lactate measurements in human immunodeficiency virus-uninfected children with in utero exposure to human immunodeficiency virus and antiretroviral medications. Pediatr Infect Dis J 2011; 30:1069-74. [PMID: 22051859 PMCID: PMC3242409 DOI: 10.1097/inf.0b013e318234c886] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVES To estimate the prevalence of elevated point-of-care (POC) capillary blood lactate concentrations in human immunodeficiency virus (HIV)-exposed, uninfected children (HEU) and to determine if POC lactate varies with in utero antiretroviral (ARV) exposure. METHODS The Surveillance Monitoring for Antiretroviral Therapy Toxicities protocol of the Pediatric HIV/AIDS Cohort Study enrolled 1934 children between 2007 and 2009, 0 to 12 years of age, born to HIV-infected mothers. POC lactate was measured annually on capillary blood using the Lactate Pro device. Associations of POC lactate with in utero ARV exposure and other characteristics were evaluated using logistic regression models, adjusting for maternal characteristics and other confounders. RESULTS Of 1641 children with POC measurements (median age, 3.0 years), 3.4% had POC lactate >3 mmol/L. Median POC lactate level decreased with age (1.9 mmol/L, 1.7 mmol/L, and 1.6 mmol/L for children 0-<6 months [99% ≤6 weeks of life], 6-<24 months, and ≥24 months of age, respectively; P < 0.001). Prevalence of elevated POC lactate did not differ by in utero ARV exposure drug class, but was significantly higher in children exposed in utero to emtricitabine or efavirenz, cocaine or opiates, and those of white race. CONCLUSIONS POC lactate testing is a useful rapid laboratory screening assay for HEU children with ARV exposure. ARV use during pregnancy has resulted in a dramatic decrease in mother-to-child transmission of HIV, and the risk of elevated lactate in HEU children is low. However, as new ARVs and more complex regimens are used during pregnancy by HIV-infected women, continued monitoring for infant toxicities is essential.
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Qu F, Liu X, Zhou F, Yang H, Bao G, He X, Xing J. Association between mitochondrial DNA content in leukocytes and colorectal cancer risk: a case-control analysis. Cancer 2011; 117:3148-55. [PMID: 21246538 DOI: 10.1002/cncr.25906] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Revised: 12/06/2010] [Accepted: 12/07/2010] [Indexed: 12/13/2022]
Abstract
BACKGROUND Compelling epidemiological evidence indicated that alterations of mitochondrial DNA (mtDNA), including mutations and abnormal content of mtDNA, were implicated in the tumorigenesis of several malignancies in a tumor-specific manner, such as lung cancer, breast cancer, and non-Hodgkin lymphoma. This study was undertaken to investigate whether mtDNA content in peripheral blood lymphocytes (PBLs) could be used as a risk predictor for colorectal cancer (CRC). METHODS The mtDNA content was measured by using quantitative real-time polymerase chain reaction in PBLs from 320 CRC patients and 320 matched controls. RESULTS The authors found that CRC patients exhibited statistically significantly higher mtDNA content than matched controls (median, 1.03 vs .86; P < .001). They further assessed the association between mtDNA content and CRC risk using multivariate logistic regression. By using the median value in controls as the cutoff point, they found that, compared with low mtDNA content, high mtDNA content was associated with a significantly increased CRC risk (adjusted odds ratio, 2.03; 95% confidence interval, 1.41-2.81). In a trend analysis, they found a statistically significant dose-response relationship between higher mtDNA content and increased CRC risk (P for trend <.001). Stratified analysis showed that the association between mtDNA content and CRC risk was not modulated by major host characteristics. CONCLUSIONS These findings provide the first epidemiological evidence linking the high mtDNA content in PBLs to elevated CRC risk.
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Affiliation(s)
- Falin Qu
- Department of General Surgery, Tangdu Hospital, Fourth Military Medical University, Xi'an, China
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Reiling E, Ling C, Uitterlinden AG, Van't Riet E, Welschen LMC, Ladenvall C, Almgren P, Lyssenko V, Nijpels G, van Hove EC, Maassen JA, de Geus EJC, Boomsma DI, Dekker JM, Groop L, Willemsen G, 't Hart LM. The association of mitochondrial content with prevalent and incident type 2 diabetes. J Clin Endocrinol Metab 2010; 95:1909-15. [PMID: 20150578 DOI: 10.1210/jc.2009-1775] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
CONTEXT It has been shown that mitochondrial DNA (mtDNA) content is associated with type 2 diabetes (T2D) and related traits. However, empirical data, often based on small samples, did not confirm this observation in all studies. Therefore, the role of mtDNA content in T2D remains elusive. OBJECTIVE In this study, we assessed the heritability of mtDNA content in buccal cells and analyzed the association of mtDNA content in blood with prevalent and incident T2D. DESIGN AND SETTING mtDNA content from cells from buccal and blood samples was assessed using a real-time PCR-based assay. Heritability of mtDNA content was estimated in 391 twins from the Netherlands Twin Register. The association with prevalent T2D was tested in a case control study from The Netherlands (n = 329). Incident T2D was analyzed using prospective samples from Finland (n = 444) and The Netherlands (n = 238). MAIN OUTCOME MEASURES We measured the heritability of mtDNA content and the association of mtDNA content in blood with prevalent and incident T2D. RESULTS A heritability of mtDNA content of 35% (19-48%) was estimated in the twin families. We did not observe evidence of an association between mtDNA content and prevalent or incident T2D and related traits. Furthermore, we observed a decline in mtDNA content with increasing age that was male specific (P = 0.001). CONCLUSION In this study, we show that mtDNA content has a heritability of 35% in Dutch twins. There is no association between mtDNA content in blood and prevalent or incident T2D and related traits in our study samples.
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Affiliation(s)
- Erwin Reiling
- Leiden University Medical Center, Department of Molecular Cell Biology, P.O. Box 9600, 2300 RC Leiden, The Netherlands
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Genetic variation in PARL influences mitochondrial content. Hum Genet 2009; 127:183-90. [PMID: 19862556 DOI: 10.1007/s00439-009-0756-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Accepted: 10/13/2009] [Indexed: 12/19/2022]
Abstract
Given their involvement in processes necessary for life, mitochondrial damage and subsequent dysfunction can lead to a wide range of human diseases. Previous studies of both animal models and humans have suggested that presenilins-associated rhomboid-like protein (PARL) is a key regulator of mitochondrial integrity and function, and plays a role in cellular apoptosis. As a surrogate measure of mitochondrial integrity, we previously measured mitochondrial content in a Caucasian population consisting of large extended pedigrees, with results highlighting a substantial genetic component to this trait. To assess the influence of variation in the PARL gene on mitochondrial content, we re-sequenced 6.5 kb of the gene, identifying 16 SNPs and genotyped these in 1,086 Caucasian individuals, distributed across 170 families. Statistical genetic analysis revealed that one promoter variant, T-191C, exhibited significant effects (after correction for multiple testing) on mitochondrial content levels. Comparison of the transcription factor binding characteristics of the T-191C promoter SNP by EMSA indicates preferential binding of nuclear factors to the T allele, suggesting functional variation in PARL expression. These results suggest that genetic variation within PARL influences mitochondrial abundance and integrity.
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Wong J, McLennan SV, Molyneaux L, Min D, Twigg SM, Yue DK. Mitochondrial DNA content in peripheral blood monocytes: relationship with age of diabetes onsetand diabetic complications. Diabetologia 2009; 52:1953-61. [PMID: 19629432 DOI: 10.1007/s00125-009-1424-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 04/27/2009] [Indexed: 02/07/2023]
Abstract
AIMS/HYPOTHESIS We examined whether age of type 2 diabetes onset is related to mitochondrial DNA content in peripheral blood monocytes (PBMCs). METHODS PBMCs were isolated from 65 patients with type 2 diabetes. To minimise age as a confounder, only patients aged >or=50 years were studied. Sample mitochondrial DNA (mtDNA) content was determined by amplification of the mitochondrial gene CYT-B (also known as MT-CYB) and adjusted for single-copy nuclear control genes (36B4 [also known as RPLPO] and GAPDH). RESULTS Age of diabetes onset ranged from 25 to 69 years. There was a significant positive relationship between age of diabetes onset in quartiles and mtDNA content for the whole group (p = 0.02 for trend). When stratified by the presence of diabetes complications, a strong positive relationship was observed between age of diagnosis and mtDNA content for participants without diabetic complications (r = 0.7; p = 0.0002), but not for those with complications (r = -0.04; p = 0.8). Multivariate analysis confirmed age of onset and complication status as independent determinants. There was co-linearity between age of onset and disease duration, with similar relationships also seen between duration and mtDNA content. CONCLUSIONS/INTERPRETATION An earlier age of type 2 diabetes onset is associated with a lower PBMC mtDNA content, but only in patients without diabetes complications. This may reflect a differing biology of PBMC mtDNA in those with early-onset diabetes and those who are prone to complications. PBMC mtDNA depletion may accelerate diabetes onset; however the independent effect of diabetes duration remains to be evaluated.
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Affiliation(s)
- J Wong
- Diabetes Centre, Royal Prince Alfred Hospital, Level 6, West Wing, Missenden Road, Camperdown, Sydney, NSW, 2050, Australia.
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Cormio A, Milella F, Marra M, Pala M, Lezza AMS, Bonfigli AR, Franceschi C, Cantatore P, Gadaleta MN. Variations at the H-strand replication origins of mitochondrial DNA and mitochondrial DNA content in the blood of type 2 diabetes patients. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:547-52. [PMID: 19344660 DOI: 10.1016/j.bbabio.2009.01.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Revised: 01/12/2009] [Accepted: 01/15/2009] [Indexed: 01/26/2023]
Abstract
Mitochondrial DNA (mtDNA) sequence variation in the segment of the D-loop region encompassing the initiation sites for replication and transcription was analyzed in the blood of 277 Italian type 2 diabetes patients and 277 Italian healthy subjects. Compared with the Cambridge Reference Sequence, diabetic patients show a slightly higher propensity to accumulate base changes in this region, with respect to controls, although no significant association can be established between any of the detected changes and the diabetic condition. Subjects, patients and controls, harbouring base changes at the replication origins (positions 57 and 151) and at position 58 were analyzed for mtDNA content. The mtDNA content increased three-four times only in the diabetic patients bearing the m.151C>T transition, whereas in those bearing the m.58T>C change the mtDNA content doubled, independently of the affiliation haplogroup. This result suggests that the m.151C>T transition and, to a lower extent, the m.58T>C might confer to the blood cells of diabetic patients the capability of increasing their mtDNA content, whereas the same transitions have no effect on control subjects.
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Affiliation(s)
- Antonella Cormio
- Department of Biochemistry and Molecular Biology E. Quagliariello, University of Bari, Via Orabona, 4 -70125- Bari, Italy
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Hong MG, Myers AJ, Magnusson PKE, Prince JA. Transcriptome-wide assessment of human brain and lymphocyte senescence. PLoS One 2008; 3:e3024. [PMID: 18714388 PMCID: PMC2515343 DOI: 10.1371/journal.pone.0003024] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Accepted: 08/01/2008] [Indexed: 01/09/2023] Open
Abstract
Background Identifying biological pathways that vary across the age spectrum can provide insight into fundamental mechanisms that impact disease and frailty in the elderly. Few methodological approaches offer the means to explore this question on as broad a scale as gene expression profiling. Here, we have evaluated mRNA expression profiles as a function of age in two populations; one consisting of 191 individuals with ages-at-death ranging from 65–100 years and with post-mortem brain mRNA measurements of 13,216 genes and a second with 1240 individuals ages 15–94 and lymphocyte mRNA estimates for 18,519 genes. Principal Findings Among negatively correlated transcripts, an enrichment of mitochondrial genes was evident in both populations, providing a replication of previous studies indicating this as a common signature of aging. Sample differences were prominent, the most significant being a decrease in expression of genes involved in translation in lymphocytes and an increase in genes involved in transcription in brain, suggesting that apart from energy metabolism other basic cell processes are affected by age but in a tissue-specific manner. In assessing genomic architecture, intron/exon sequence length ratios were larger among negatively regulated genes in both samples, suggesting that a decrease in the expression of non-compact genes may also be a general effect of aging. Variance in gene expression itself has been theorized to change with age due to accumulation of somatic mutations and/or increasingly heterogeneous environmental exposures, but we found no evidence for such a trend here. Significance Results affirm that deteriorating mitochondrial gene expression is a common theme in senescence, but also highlight novel pathways and features of gene architecture that may be important for understanding the molecular consequences of aging.
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Affiliation(s)
- Mun-Gwan Hong
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Amanda J. Myers
- Department of Psychiatry, University of Miami, Miller School of Medicine, Miami, Florida, United States of America
| | - Patrik K. E. Magnusson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Jonathan A. Prince
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- * E-mail:
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Xing J, Chen M, Wood CG, Lin J, Spitz MR, Ma J, Amos CI, Shields PG, Benowitz NL, Gu J, de Andrade M, Swan GE, Wu X. Mitochondrial DNA content: its genetic heritability and association with renal cell carcinoma. J Natl Cancer Inst 2008; 100:1104-12. [PMID: 18664653 DOI: 10.1093/jnci/djn213] [Citation(s) in RCA: 211] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The extent to which mitochondrial DNA (mtDNA) content (also termed mtDNA copy number) in normal human cells is influenced by genetic factors has yet to be established. In addition, whether inherited variation of mtDNA content in normal cells contributes to cancer susceptibility remains unclear. Renal cell carcinoma accounts for 85% of all renal cancers. No studies have investigated the association between mtDNA content and the risk of renal cell carcinoma. METHODS We first used a classic twin study design to estimate the genetic contribution to the determination of mtDNA content. mtDNA content was measured by quantitative real-time polymerase chain reaction in peripheral blood lymphocytes from 250 monozygotic twins, 92 dizygotic twins, and 33 siblings (ie, individual siblings of a pair of twins). We used biometric genetic modeling to estimate heritability of mtDNA content. We then used a case-control study with 260 case patients with renal cell carcinoma and 281 matched control subjects and multivariable logistic regression analysis to examine the association between mtDNA content in peripheral blood lymphocytes and the risk of renal cell carcinoma. All statistical tests were two-sided. RESULTS The heritability (ie, proportion of phenotypic variation in a population that is attributable to genetic variation among individuals) of mtDNA content was 65% (95% confidence interval [CI] = 50% to 72%; P < .001). Case patients with renal cell carcinoma had a statistically significantly lower mtDNA content (1.18 copies) than control subjects (1.29 copies) (difference = 0.11, 95% CI = 0.03 to 0.17; P = .006). Low mtDNA content (ie, less than the median in control subjects) was associated with a statistically significantly increased risk of renal cell carcinoma, compared with high content (odds ratio = 1.53, 95% CI = 1.07 to 2.19). In a trend analysis, a statistically significant dose-response relationship was detected between lower mtDNA content and increasing risk of renal cell carcinoma (P for trend <.001). CONCLUSIONS mtDNA content appears to have high heritability. Low mtDNA content appears to be associated with increased risk of renal cell carcinoma.
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Affiliation(s)
- Jinliang Xing
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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