1
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Herbst A, Widjaja K, Nguy B, Lushaj EB, Moore TM, Hevener AL, McKenzie D, Aiken JM, Wanagat J. Digital PCR Quantitation of Muscle Mitochondrial DNA: Age, Fiber Type, and Mutation-Induced Changes. J Gerontol A Biol Sci Med Sci 2017; 72:1327-1333. [PMID: 28460005 DOI: 10.1093/gerona/glx058] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 03/21/2017] [Indexed: 01/07/2023] Open
Abstract
Definitive quantitation of mitochondrial DNA (mtDNA) and mtDNA deletion mutation abundances would help clarify the role of mtDNA instability in aging. To more accurately quantify mtDNA, we applied the emerging technique of digital polymerase chain reaction to individual muscle fibers and muscle homogenates from aged rodents. Individual fiber mtDNA content correlated with fiber type and decreased with age. We adapted a digital polymerase chain reaction deletion assay that was accurate in mixing experiments to a mutation frequency of 0.03% and quantitated an age-induced increase in deletion frequency from rat muscle homogenates. Importantly, the deletion frequency measured in muscle homogenates strongly correlated with electron transport chain-deficient fiber abundance determined by histochemical analyses. These data clarify the temporal accumulation of mtDNA deletions that lead to electron chain-deficient fibers, a process culminating in muscle fiber loss.
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Affiliation(s)
- Allen Herbst
- Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, Canada
| | - Kevin Widjaja
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles
| | - Beatrice Nguy
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles
| | - Entela B Lushaj
- Department of Surgery, School of Medicine and Public Health, University of Wisconsin, Madison
| | - Timothy M Moore
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles
| | - Andrea L Hevener
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles
| | - Debbie McKenzie
- Department of Biological Sciences, University of Alberta, Edmonton, Canada
| | - Judd M Aiken
- Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, Canada
| | - Jonathan Wanagat
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles
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2
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Wanagat J, Hevener AL. Mitochondrial quality control in insulin resistance and diabetes. Curr Opin Genet Dev 2016; 38:118-126. [PMID: 27318536 DOI: 10.1016/j.gde.2016.05.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 05/12/2016] [Accepted: 05/18/2016] [Indexed: 01/07/2023]
Abstract
Diabetes is increasingly prevalent and a primary contributor to the major causes of disability and death. Despite the central role of mitochondria in metabolism, the relationship between mitochondrial quality and insulin action remains unclear. An increasing number of genetically-engineered and aging rodent models are shedding additional light on the mitochondrion's role in regulating glucose metabolism and insulin sensitivity by modulating mitochondrial morphology, function and quality control pathways. Clarification of the role of mitochondria in regulating key cellular processes including metabolic flux, autophagy, and apoptosis will drive the development of novel therapeutic strategies for maintaining mitochondrial quality and improving human health.
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Affiliation(s)
- Jonathan Wanagat
- UCLA David Geffen School of Medicine, Department of Medicine, Division of Geriatrics, Los Angeles, CA 90095, United States.
| | - Andrea L Hevener
- UCLA David Geffen School of Medicine, Department of Medicine, Division of Endocrinology, Diabetes and Hypertension, Los Angeles, CA 90095, United States.
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3
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Kazachkova N, Ramos A, Santos C, Lima M. Mitochondrial DNA damage patterns and aging: revising the evidences for humans and mice. Aging Dis 2013; 4:337-50. [PMID: 24307967 DOI: 10.14336/ad.2013.0400337] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 09/04/2013] [Accepted: 09/06/2013] [Indexed: 01/07/2023] Open
Abstract
A significant body of work, accumulated over the years, strongly suggests that damage in mitochondrial DNA (mtDNA) contributes to aging in humans. Contradictory results, however, are reported in the literature, with some studies failing to provide support to this hypothesis. With the purpose of further understanding the aging process, several models, among which mouse models, have been frequently used. Although important affinities are recognized between humans and mice, differences on what concerns physiological properties, disease pathogenesis as well as life-history exist between the two; the extent to which such differences limit the translation, from mice to humans, of insights on the association between mtDNA damage and aging remains to be established. In this paper we revise the studies that analyze the association between patterns of mtDNA damage and aging, investigating putative alterations in mtDNA copy number as well as accumulation of deletions and of point mutations. Reports from the literature do not allow the establishment of a clear association between mtDNA copy number and age, either in humans or in mice. Further analysis, using a wide spectrum of tissues and a high number of individuals would be necessary to elucidate this pattern. Likewise humans, mice demonstrated a clear pattern of age-dependent and tissue-specific accumulation of mtDNA deletions. Deletions increase with age, and the highest amount of deletions has been observed in brain tissues both in humans and mice. On the other hand, mtDNA point mutations accumulation has been clearly associated with age in humans, but not in mice. Although further studies, using the same methodologies and targeting a larger number of samples would be mandatory to draw definitive conclusions, the revision of the available data raises concerns on the ability of mouse models to mimic the mtDNA damage patterns of humans, a fact with implications not only for the study of the aging process, but also for investigations of other processes in which mtDNA dysfunction is a hallmark, such as neurodegeneration.
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Affiliation(s)
- Nadiya Kazachkova
- Centre of Research in Natural Resources (CIRN), Department of Biology, University of the Azores, Ponta Delgada, Portugal ; Institute for Molecular and Cell Biology (IBMC), University of Porto, Porto, Portugal
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4
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Liu D, Li H, Lu J, Bai Y. Tissue-specific implications of mitochondrial alterations in aging. Front Biosci (Elite Ed) 2013; 5:734-47. [PMID: 23277028 DOI: 10.2741/e654] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Aging is a multifactorial process during which physiological alterations occur in all tissues. A decline in mitochondrial function plays an important role in the process of aging and in aging-associated diseases. The mitochondrial genome encodes 13 essential subunits of protein complexes belonging to the oxidative phosphorylation system, while most of the mitochondria-related genes are encoded by the nuclear genome. Coordination between the nucleus and mitochondria is crucial for the regulation of mitochondrial biogenesis and function. In this review, we will discuss aging-related mitochondrial dysfunction in various tissues and its implication in aging-related diseases and the aging process.
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Affiliation(s)
- Danhui Liu
- Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang 325035, China
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5
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Oxidative stress, mitochondrial dysfunction, and aging. JOURNAL OF SIGNAL TRANSDUCTION 2011; 2012:646354. [PMID: 21977319 PMCID: PMC3184498 DOI: 10.1155/2012/646354] [Citation(s) in RCA: 576] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/15/2011] [Accepted: 08/03/2011] [Indexed: 12/31/2022]
Abstract
Aging is an intricate phenomenon characterized by progressive decline in physiological functions and increase in mortality that is often accompanied by many pathological diseases. Although aging is almost universally conserved among all organisms, the underlying molecular mechanisms of aging remain largely elusive. Many theories of aging have been proposed, including the free-radical and mitochondrial theories of aging. Both theories speculate that cumulative damage to mitochondria and mitochondrial DNA (mtDNA) caused by reactive oxygen species (ROS) is one of the causes of aging. Oxidative damage affects replication and transcription of mtDNA and results in a decline in mitochondrial function which in turn leads to enhanced ROS production and further damage to mtDNA. In this paper, we will present the current understanding of the interplay between ROS and mitochondria and will discuss their potential impact on aging and age-related diseases.
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6
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Hiona A, Sanz A, Kujoth GC, Pamplona R, Seo AY, Hofer T, Someya S, Miyakawa T, Nakayama C, Samhan-Arias AK, Servais S, Barger JL, Portero-Otín M, Tanokura M, Prolla TA, Leeuwenburgh C. Mitochondrial DNA mutations induce mitochondrial dysfunction, apoptosis and sarcopenia in skeletal muscle of mitochondrial DNA mutator mice. PLoS One 2010; 5:e11468. [PMID: 20628647 PMCID: PMC2898813 DOI: 10.1371/journal.pone.0011468] [Citation(s) in RCA: 200] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Accepted: 05/18/2010] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Aging results in a progressive loss of skeletal muscle, a condition known as sarcopenia. Mitochondrial DNA (mtDNA) mutations accumulate with aging in skeletal muscle and correlate with muscle loss, although no causal relationship has been established. METHODOLOGY/PRINCIPAL FINDINGS We investigated the relationship between mtDNA mutations and sarcopenia at the gene expression and biochemical levels using a mouse model that expresses a proofreading-deficient version (D257A) of the mitochondrial DNA Polymerase gamma, resulting in increased spontaneous mtDNA mutation rates. Gene expression profiling of D257A mice followed by Parametric Analysis of Gene Set Enrichment (PAGE) indicates that the D257A mutation is associated with a profound downregulation of gene sets associated with mitochondrial function. At the biochemical level, sarcopenia in D257A mice is associated with a marked reduction (35-50%) in the content of electron transport chain (ETC) complexes I, III and IV, all of which are partly encoded by mtDNA. D257A mice display impaired mitochondrial bioenergetics associated with compromised state-3 respiration, lower ATP content and a resulting decrease in mitochondrial membrane potential (Deltapsim). Surprisingly, mitochondrial dysfunction was not accompanied by an increase in mitochondrial reactive oxygen species (ROS) production or oxidative damage. CONCLUSIONS/SIGNIFICANCE These findings demonstrate that mutations in mtDNA can be causal in sarcopenia by affecting the assembly of functional ETC complexes, the lack of which provokes a decrease in oxidative phosphorylation, without an increase in oxidative stress, and ultimately, skeletal muscle apoptosis and sarcopenia.
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Affiliation(s)
- Asimina Hiona
- Division of Biology of Aging, Department of Aging and Geriatric Research, Institute on Aging, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Alberto Sanz
- Mitochondrial Gene Expression and Disease Group. Institute of Medical Technology and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Gregory C. Kujoth
- Department of Genetics and Medical Genetics, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Reinald Pamplona
- Department of Experimental Medicine, University of Lleida-Institut de Recerca Biomèdica de Lleida, Lleida, Spain
| | - Arnold Y. Seo
- Division of Biology of Aging, Department of Aging and Geriatric Research, Institute on Aging, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Tim Hofer
- Division of Biology of Aging, Department of Aging and Geriatric Research, Institute on Aging, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Shinichi Someya
- Department of Genetics and Medical Genetics, University of Wisconsin, Madison, Wisconsin, United States of America
- Department of Applied Biological Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Takuya Miyakawa
- Department of Applied Biological Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Chie Nakayama
- Department of Applied Biological Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Alejandro K. Samhan-Arias
- Department of Biochemistry and Molecular Biology, Faculty of Sciences, University of Extremadura, Badajoz, Spain
| | - Stephane Servais
- Division of Biology of Aging, Department of Aging and Geriatric Research, Institute on Aging, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Jamie L. Barger
- LifeGen Technologies, LLC, Madison, Wisconsin, United States of America
| | - Manuel Portero-Otín
- Department of Experimental Medicine, University of Lleida-Institut de Recerca Biomèdica de Lleida, Lleida, Spain
| | - Masaru Tanokura
- Department of Applied Biological Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Tomas A. Prolla
- Department of Genetics and Medical Genetics, University of Wisconsin, Madison, Wisconsin, United States of America
- * E-mail: (TAP); (CL)
| | - Christiaan Leeuwenburgh
- Division of Biology of Aging, Department of Aging and Geriatric Research, Institute on Aging, College of Medicine, University of Florida, Gainesville, Florida, United States of America
- * E-mail: (TAP); (CL)
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7
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Herbst A, Pak JW, McKenzie D, Bua E, Bassiouni M, Aiken JM. Accumulation of mitochondrial DNA deletion mutations in aged muscle fibers: evidence for a causal role in muscle fiber loss. J Gerontol A Biol Sci Med Sci 2007; 62:235-45. [PMID: 17389720 PMCID: PMC2846622 DOI: 10.1093/gerona/62.3.235] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Although mitochondrial mutation abundance has been recognized to increase in an age-dependent manner, the impact of mutation has been more difficult to establish. Using quantitative polymerase chain reaction, we measured the intracellular abundance of mutant and wild-type mitochondrial genomes along the length of individual laser-captured microdissected muscle fibers from aged rat quadriceps. Aged muscle fibers possessed segmental, clonal intracellular expansions of unique somatically derived mitochondrial DNA (mtDNA) deletion mutations. When the mutation abundance surpassed 90% of the total mitochondrial genomes, the fiber lost cytochrome c oxidase activity and exhibited an increase in succinate dehydrogenase activity. In addition to the mitochondrial enzymatic abnormalities, some fibers displayed abnormal morphology such as fiber splitting, atrophy, and breakage. Deletion mutation accumulation was linked to these aberrant morphologies with more severe cellular pathologies resulting from higher deletion mutation abundance. In summary, our measurements indicate that age-induced mtDNA deletion mutations expand within individual muscle fibers, eliciting fiber dysfunction and breakage.
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Dubessay P, Garreau-Balandier I, Jarrousse AS, Fleuriet A, Sion B, Debise R, Alziari S. Aging impact on biochemical activities and gene expression of Drosophila melanogaster mitochondria. Biochimie 2007; 89:988-1001. [PMID: 17524546 DOI: 10.1016/j.biochi.2007.03.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2007] [Accepted: 03/19/2007] [Indexed: 11/21/2022]
Abstract
The consequences of aging are characterized by a decline in the main cellular functions, including those of the mitochondria. Although these consequences have been much studied, efforts have often focused solely on a few parameters used to assess the "state" of mitochondrial function during aging. We performed comparative measurements of several parameters in young (a few days) and old (8 and 12 weeks) adult male Drosophila melanogaster: respiratory complex activities, mitochondrial respiration, ATP synthesis, lipid composition of the inner membrane, concentrations of respiratory complex subunits, expression of genes (nuclear and mitochondrial) coding for mitochondrial proteins. Our results show that, in the mitochondria of "old" flies, the activities of three respiratory complexes (I, III, IV) are greatly diminished, ATP synthesis is decreased, and the lipid composition of the inner membrane (fatty acids, cardiolipin) is modified. However, the respiration rate and subunit concentrations measured by Western blot are unaffected. Although cellular mitochondrial DNA (mtDNA) content remains constant, there is a decrease in concentrations of nuclear and mitochondrial transcripts apparently coordinated. The expression of nuclear genes encoding the transcription factors TFAM, TFB1, TFB2, and DmTTF, which are essential for the maintenance and expression of mtDNA are also decreased. The decrease in nuclear and mitochondrial transcript concentrations may be one of the principal effects of aging on mitochondria, and could explain observed decreases in mitochondrial efficiency.
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Affiliation(s)
- Pascal Dubessay
- Equipe Génome Mitochondrial, UMR CNRS 6547, Université Blaise Pascal-Clermont II, 63177 Aubière, France
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9
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Bua E, Johnson J, Herbst A, Delong B, McKenzie D, Salamat S, Aiken JM. Mitochondrial DNA-deletion mutations accumulate intracellularly to detrimental levels in aged human skeletal muscle fibers. Am J Hum Genet 2006; 79:469-80. [PMID: 16909385 PMCID: PMC1559550 DOI: 10.1086/507132] [Citation(s) in RCA: 305] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2006] [Accepted: 06/12/2006] [Indexed: 12/18/2022] Open
Abstract
Skeletal muscle-mass loss with age has severe health consequences, yet the molecular basis of the loss remains obscure. Although mitochondrial DNA (mtDNA)-deletion mutations have been shown to accumulate with age, for these aberrant genomes to be physiologically relevant, they must accumulate to high levels intracellularly and be present in a significant number of cells. We examined mtDNA-deletion mutations in vastus lateralis (VL) muscle of human subjects aged 49-93 years, using both histologic and polymerase-chain-reaction (PCR) analyses, to determine the physiological and genomic integrity of mitochondria in aging human muscle. The number of VL muscle fibers exhibiting mitochondrial electron-transport-system (ETS) abnormalities increased from an estimated 6% at age 49 years to 31% at age 92 years. We analyzed the mitochondrial genotype of 48 single ETS-abnormal, cytochrome c oxidase-negative/succinate dehydrogenase-hyperreactive (COX-/SDH++) fibers from normal aging human subjects and identified mtDNA-deletion mutations in all abnormal fibers. Deletion mutations were clonal within a fiber and concomitant to the COX-/SDH++ region. Quantitative PCR analysis of wild-type and deletion-containing mtDNA genomes within ETS-abnormal regions of single fibers demonstrated that these deletion mutations accumulate to detrimental levels (>90% of the total mtDNA).
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MESH Headings
- Aged
- Aged, 80 and over
- Aging/genetics
- DNA, Mitochondrial/analysis
- DNA, Mitochondrial/genetics
- Electron Transport/genetics
- Electron Transport Chain Complex Proteins/genetics
- Electron Transport Complex IV/genetics
- Female
- Humans
- Male
- Middle Aged
- Mitochondria, Muscle/enzymology
- Mitochondria, Muscle/genetics
- Muscle Fibers, Skeletal/chemistry
- Muscle Fibers, Skeletal/cytology
- Muscle Fibers, Skeletal/enzymology
- Muscle, Skeletal/chemistry
- Muscle, Skeletal/cytology
- Muscle, Skeletal/enzymology
- Sequence Deletion
- Succinate Dehydrogenase/genetics
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Affiliation(s)
- Entela Bua
- Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison, WI 53706, USA
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10
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Iwai K, Iwamura Y, Yamashita S, Wadano Y, Mesaki N. Effect of tea catechins on mitochondrial DNA 4977-bp deletions in human leucocytes. Mutat Res 2006; 595:191-5. [PMID: 16289599 DOI: 10.1016/j.mrfmmm.2005.10.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Revised: 09/02/2005] [Accepted: 10/06/2005] [Indexed: 05/05/2023]
Abstract
The catechins in green tea have antioxidative and antimutagenic effects. We examined the effect of green tea enriched with catechins on the presence of mitochondrial DNA (mtDNA) with a common 4977-bp deletion mutation (mtDNA4977) in human leucocytes. Ten healthy females [aged 20.80 +/- 1.03 years] drank 350 ml of catechin-rich tea daily after supper for 5 weeks. Blood samples were collected twice before, and twice after 5 weeks of consuming the tea. Deletions in mtDNA were analyzed using the nested polymerase chain reaction (PCR). We identified a common mtDNA4977 deletion in nine participants before drinking the tea. However, this mtDNA4977 deletion was not evident in leucocytes from most of the participants 5 weeks after drinking the tea. Catechins found in tea might contribute to the maintenance of health status by reducing damage to mtDNA and by maintaining the capacity of mtDNA for oxidative phosphorylation.
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Affiliation(s)
- Koichi Iwai
- Center for Humanity and Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami, Inashiki, Ibaraki 300-0394, Japan.
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11
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Semba RD, Blaum C, Guralnik JM, Moncrief DT, Ricks MO, Fried LP. Carotenoid and vitamin E status are associated with indicators of sarcopenia among older women living in the community. Aging Clin Exp Res 2003; 15:482-7. [PMID: 14959951 DOI: 10.1007/bf03327377] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND AIMS Oxidative stress may play a role in the pathogenesis of sarcopenia, and the relationship between dietary antioxidants and sarcopenia needs further elucidation. The aim was to determine whether dietary carotenoids and alpha-tocopherol are associated with sarcopenia, as indicated by low grip, hip, and knee strength. METHODS Cross-sectional analyses were conducted on 669 non-disabled to severely disabled community-dwelling women aged 70 to 79 who participated in the Women's Health and Aging Studies. Plasma carotenoids and alpha-tocopherol were measured. Grip, hip, and knee strength were measured, and low strength was defined as the lowest tertile of each strength measure. RESULTS Higher plasma concentrations of alpha-carotene, beta-carotene, beta-cryptoxanthin, and lutein/zeaxanthin were associated with reduced risk of low grip, hip, and knee strength. After adjusting for potential confounding factors such as age, race, smoking, cardiovascular disease, arthritis, and plasma interleukin-6 concentrations, there was an independent association for women in the highest compared with the lowest quartile of total carotenoids with low grip strength [Odds Ratios (OR) 0.34, 95% Confidence Interval (CI) 0.20-0.59], low hip strength (OR 0.28, 95% CI 0.16-0.48), and low knee strength (OR 0.45, 95% CI 0.27-0.75), and there was an independent association for women in the highest compared with the lowest quartile of alpha-tocopherol with low grip strength (OR 0.44, 95% CI 0.24-0.78) and low knee strength (OR 0.52, 95% CI 0.29-0.95). CONCLUSIONS Higher carotenoid and alpha-tocopherol status were independently associated with higher strength measures. These data support the hypothesis that oxidative stress is associated with sarcopenia in older adults, but further longitudinal and interventional studies are needed to establish causality.
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12
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Arai T, Nakahara KI, Matsuoka H, Sawabe M, Chida K, Matsushita S, Takubo K, Honma N, Nakamura KI, Izumiyama N, Esaki Y. Age-related mitochondrial DNA deletion in human heart: its relationship with cardiovascular diseases. Aging Clin Exp Res 2003; 15:1-5. [PMID: 12841411 DOI: 10.1007/bf03324472] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Accumulation of damage to mitochondrial DNA (mtDNA) occurs in myocardial tissue with advancing age. However, despite higher incidence of cardiac diseases in the elderly, little attempt has been made to detect deletions of mtDNA in the myocardial tissue of aged individuals. The aim of the present study was to clarify the relationship between aging, mtDNA deletion and cardiovascular (CV) diseases. METHODS We examined 163 autopsy cases, aged 60 years or older, using two different kinds of polymerase chain reaction (PCR): highly sensitive PCR to detect a common 4977-bp deletion and long-PCR for multiple deletions, which could be detected in case that deleted mtDNA accounted for more than several percents in total mtDNA. RESULTS The common 4977-bp deletion was detected in 156 cases (95.7%), showing no significant difference among these age groups and no relation to CV diseases. By long-PCR, multiple deletions in cardiac mtDNA were found in 33 (20.2%) of 163 cases. The proportion of the mtDNA deletion in the nineties (46.2%) was significantly higher than those in the younger (15.3%, p < 0.05). Female predominance was significantly found in the group with the mtDNA deletion (p < 0.05). Multiple deletions of mtDNA were not significantly related to ischemic change, valvular diseases, left ventricular hypertrophy, congestive heart failure, coronary sclerosis, or heart weight except for right ventricular hypertrophy. CONCLUSIONS These findings suggest that there is a close relationship between aging and deletion of mtDNA, and that the ratio of deleted mtDNA to total mtDNA increases with advancing age. Age-related deletion of mtDNA may have little influence on CV diseases except for right ventricular hypertrophy.
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Affiliation(s)
- Tomio Arai
- Departments of Pathology, Tokyo Metropolitan Geriatric Medical Center, Tokyo, Japan.
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13
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Cao Z, Wanagat J, McKiernan SH, Aiken JM. Mitochondrial DNA deletion mutations are concomitant with ragged red regions of individual, aged muscle fibers: analysis by laser-capture microdissection. Nucleic Acids Res 2001; 29:4502-8. [PMID: 11691938 PMCID: PMC60181 DOI: 10.1093/nar/29.21.4502] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Laser-capture microdissection was coupled with PCR to define the mitochondrial genotype of aged muscle fibers exhibiting mitochondrial enzymatic abnormalities. These electron transport system (ETS) abnormalities accumulate with age, are localized segmentally along muscle fibers, are associated with fiber atrophy and may contribute to age-related fiber loss. DNA extracted from single, 10 microm thick, ETS abnormal muscle fibers, as well as sections from normal fibers, served as templates for PCR-based deletion analysis. Large mitochondrial (mt) DNA deletion mutations (4.4-9.7 kb) were detected in all 29 ETS abnormal fibers analyzed. Deleted mtDNA genomes were detected only in the regions of the fibers with ETS abnormalities; adjacent phenotypically normal portions of the same fiber contained wild-type mtDNA. In addition, identical mtDNA deletion mutations were found within different sections of the same abnormal region. These findings demonstrate that large deletion mutations are associated with ETS abnormalities in aged rat muscle and that, within a fiber, deletion mutations are clonal. The displacement of wild-type mtDNAs with mutant mtDNAs results in concomitant mitochondrial enzymatic abnormalities, fiber atrophy and fiber breakage.
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MESH Headings
- Aging/physiology
- Animals
- Cellular Senescence
- DNA Mutational Analysis
- DNA, Mitochondrial/genetics
- Dissection/methods
- Electron Transport
- Genome
- Genotype
- Lasers
- Male
- Mitochondria, Muscle/enzymology
- Mitochondria, Muscle/genetics
- Mitochondria, Muscle/metabolism
- Mitochondria, Muscle/pathology
- Muscle Fibers, Skeletal/metabolism
- Muscle Fibers, Skeletal/pathology
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Phenotype
- Polymerase Chain Reaction
- Rats
- Rats, Inbred BN
- Rats, Inbred F344
- Sequence Deletion/genetics
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Affiliation(s)
- Z Cao
- Department of Animal Health and Biomedical Science, 1656 Linden Drive, University of Wisconsin-Madison, Madison, WI 53706, USA
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14
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Abstract
Advances in understanding of mitochondrial physiology and genetics in relation to pathology have exploded in the last decade. Paralleling this increase has been an active debate about the role of mitochondrial oxidative stress with regard to mitochondrial DNA mutations, aging, and disease. We discuss in a historical context the rapid progress in our understanding of the role of mitochondrial DNA mutations in disease, mitochondrial oxidative stress in aging, and the potential interplay between these two phenomena.
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Affiliation(s)
- T R Golden
- Buck Institute for Age Research, 8001 Redwood Blvd., Novato, CA 94945, USA
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15
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Melov S, Schneider JA, Coskun PE, Bennett DA, Wallace DC. Mitochondrial DNA rearrangements in aging human brain and in situ PCR of mtDNA. Neurobiol Aging 1999; 20:565-71. [PMID: 10638530 DOI: 10.1016/s0197-4580(99)00092-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Deletions of the mitochondrial DNA (mtDNA) have been shown to accumulate with age in a variety of species regardless of mean or maximal life span. This implies that such mutations are either a molecular biomarker of senescence or that they are more causally linked to senescence itself. One assay that can be used to detect these mtDNA mutations is the long-extension polymerase chain reaction assay. This assay amplifies approximately 16 kb of the mtDNA in mammalian mitochondria and preferentially amplifies mtDNAs that are either deleted or duplicated. We have applied this assay to the aging human brain and found a heterogeneous array of rearranged mtDNAs. In addition, we have developed in situ polymerase chain reaction to detect mtDNA within individual cells of both the mouse and the human brain as a first step in identifying and enumerating cells containing mutant mtDNAs in situ.
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Affiliation(s)
- S Melov
- Center For Molecular Medicine, Emory University, Atlanta, GA 30322, USA.
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16
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Sakai Y, Iwamura Y, Hayashi J, Yamamoto N, Ohkoshi N, Nagata H. Acute exercise causes mitochondrial DNA deletion in rat skeletal muscle. Muscle Nerve 1999; 22:258-61. [PMID: 10024140 DOI: 10.1002/(sici)1097-4598(199902)22:2<258::aid-mus15>3.0.co;2-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The present study was conducted to determine the effects of acute overload exercise on mitochondrial DNA and the structure of skeletal muscles. Rats were forced to run for 20 min until reaching complete exhaustion. We detected the large-scale deletion (7052 bp) of mitochondrial DNA by the nested polymerase chain reaction, and also observed mitochondrial ultrastructural changes in the soleus muscle.
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Affiliation(s)
- Y Sakai
- Department of Physical Therapy, Ibaraki Prefectural University of Health Sciences, Japan
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17
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ZEELAND NATHANLVAN, WANAGAT JONATHAN, LOPEZ MARISOLE, AIKEN JUDDM. Segmental Nature of Age-Associated, Skeletal Muscle Mitochondrial Abnormalities Necessitates Three-Dimensional Analyses. ACTA ACUST UNITED AC 1999. [DOI: 10.1089/rej.1.1999.2.231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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18
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Lee CM, Lopez ME, Weindruch R, Aiken JM. Association of age-related mitochondrial abnormalities with skeletal muscle fiber atrophy. Free Radic Biol Med 1998; 25:964-72. [PMID: 9840742 DOI: 10.1016/s0891-5849(98)00185-3] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The hypothesis that mitochondrial dysfunction contributes to the senescent loss of skeletal muscle was investigated in quadriceps from 2- to 39-year old rhesus monkeys. Histological approaches, both cross-sectional (a single cross-section of the muscle) and longitudinal (multiple cross-sections of individual fibers spanning a 350-1600 microm region), were used to identify muscle fibers with abnormal mitochondrial electron transport system (ETS) enzyme activities and mitochondrial DNA deletions. Fibers were examined for two ETS activities, succinate dehydrogenase (SDH, ETS complex II) and cytochrome c oxidase (COX, ETS complex IV). The number of individual fibers containing ETS abnormalities (predominately negative for cytochrome c oxidase activity and/or hyperreactive for succinate dehydrogenase) increased with age. Deletions of the mitochondrial genome were observed in 89% of these ETS abnormal fibers. Longitudinal analysis allowed characterization of the ETS abnormal phenotype along their length. A decrease in cross-sectional area in 14% of the ETS abnormal fibers supports the hypothesis that deleted mitochondrial genomes may contribute to age-related fiber atrophy.
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Affiliation(s)
- C M Lee
- Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison 53706, USA
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19
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Moore CA, Gudikote J, Van Tuyle GC. Mitochondrial DNA rearrangements, including partial duplications, occur in young and old rat tissues. Mutat Res 1998; 421:205-17. [PMID: 9852994 DOI: 10.1016/s0027-5107(98)00169-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Using polymerase chain reaction (PCR) with back-to-back primers, 85 different mitochondrial DNA (mtDNA) rearrangements, consisting of partial duplications or mini-circles, were detected in brain, liver, and heart tissue from Fischer 344 rats. The regions around the mitochondrial tRNALeu(UUR) gene, the cluster of three tRNA genes [His, Ser(AGY), Leu(UUC)], as well as the region of the displacement loop were analyzed separately with different primer sets. Rearrangements were detected in all regions analyzed in samples taken throughout the animal life span, ranging from 1 day old to 33 months of age (senescent). Two-thirds of the rearrangements terminated at short (3-9-bp) direct repeats. Three of the different rearrangements were detected in more than one animal; the most common rearrangement was found in nine different template preparations. Two loci (hot spots) were found to be particularly susceptible to rearrangement, and both were located at sequences that exhibited highly conserved potential for secondary structure formation. The displacement loop region of 10 samples exhibited the presence of multiple tandem duplications ranging between 324 and 449 bp in length. One of these consisted of heterologous, but overlapping, repeating units. Identical PCR protocols were carried out in control experiments using a cloned fragment of mtDNA that encompassed the most common hot spot sequence. The results showed that this fragment did not artifactually generate a rearrangement junction under our PCR conditions and suggested that this sequence does not promote rearrangement mutations in bacteria during the cloning process.
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Affiliation(s)
- C A Moore
- Department of Biochemistry and Molecular Biophysics, Virginia Commonwealth University, Richmond 23298, USA
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20
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Schwarze SR, Weindruch R, Aiken JM. Decreased mitochondrial RNA levels without accumulation of mitochondrial DNA deletions in aging Drosophila melanogaster. Mutat Res 1998; 382:99-107. [PMID: 9691990 DOI: 10.1016/s1383-5726(97)00013-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Declines in electron transport system (ETS) activity have been reported to occur with advancing age in Drosophila melanogaster and many other animals. It has been proposed that these changes are importantly involved in the aging process. ETS decline has been attributed to mitochondrial nucleic acid damage. We analyzed various ages of D. melanogaster (embryos to 60-day-old adults) for the presence of mutated mitochondrial DNA (mtDNA) genomes. Although mtDNA genomes with large DNA deletions (up to 5 kb) were identified, abundance was low and remained constant throughout adult life. Therefore, these mtDNA deletions do not appear to be sufficiently abundant to cause large declines in ETS activity. Next, we analyzed various ages of D. melanogaster for the abundance of four mitochondrial-encoded and two nuclear-encoded ETS transcripts. The abundance of the mitochondrial transcripts declined 5-10-fold, while the nuclear-encoded transcripts declined 2-5-fold with advancing age. Separation of flies on the basis of flight loss was used to distinguish physiologic age from chronological age. Insects capable of flight at 30 days of age were found to have a 4-fold higher abundance of cox I mitochondrial-encoded RNA compared to flightless insects. No difference, however, was apparent in the nuclear-encoded beta-ATPase RNA level, suggesting only mitochondrial RNA (mtRNA) declines are associated with life expectancy.
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Affiliation(s)
- S R Schwarze
- Department of Animal Health and Biomedical Science, University of Wisconsin, Madison 53706, USA
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21
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Goodell S, Cortopassi G. Analysis of oxygen consumption and mitochondrial permeability with age in mice. Mech Ageing Dev 1998; 101:245-56. [PMID: 9622228 DOI: 10.1016/s0047-6374(97)00182-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Biochemical and physiological parameters have been investigated in purified liver mitochondria from C57BL/6J mice of relatively young and old age, 1 month vs. 36 months. Under identical purification conditions, mitochondria from old animals consumed significantly less O2 under state 3 conditions (i.e. with saturating ADP stimulation), consistent with a lower activity of the electron transport chain. In the absence of ADP (i.e. state 4 conditions), old mitochondria consumed significantly more O2 than young mitochondria; one possible explanation was increased mitochondrial permeability as a result of induction of the mitochondrial permeability transition (MPT), and this was investigated by the mitochondrial swelling assay. In response to induction by 20 microM Ca2+, MPT rates were observed to be variable, but significantly faster in old mitochondria (t1/2 = 105 s) than in young mitochondria (t1/2 = 155 s), and in all cases MPT was inhibitable by cyclosporin A (CsA). The implications of lower state 3 respiration, higher state 4 respiration and increased rate of MPT in old mitochondria are discussed.
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Affiliation(s)
- S Goodell
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis 95616, USA
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22
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Müller-Höcker J, Jacob U, Seibel P. Hashimoto thyroiditis is associated with defects of cytochrome-c oxidase in oxyphil Askanazy cells and with the common deletion (4,977) of mitochondrial DNA. Ultrastruct Pathol 1998; 22:91-100. [PMID: 9491221 DOI: 10.3109/01913129809032263] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The activity of cytochrome-c oxidase, the terminal enzyme of the respiratory chain (complex IV), was studied at the ultrastructural level in a case of Hashimoto thyroiditis. Cytochrome-c oxidase showed a heterogeneous reaction pattern in oxyphil cells, with scattered foci of oxyphil cells lacking cytochrome-c oxidase staining. In most of the cells the defect involved all the mitochondria, but there were also oxyphil cells with a heterogeneous mitochondrial population characterized by an intracellular coexistence of mitochondria with either intact cytochrome-c oxidase or lacking activity. Immunocytochemistry further disclosed loss of mitochondrially and nuclearly encoded subunits of the enzyme. Molecular genetic analysis of mitochondrial DNA (mtDNA) revealed the presence of the 4977 base pair deletion ("common deletion") of mtDNA (8,482-13,459) in the affected areas but not in normal thyroid tissue of the patient. The amount of deleted mtDNA varied between 2 and 8% of total mtDNA. The results demonstrate that oxyphil cell change in Hashimoto thyroiditis is associated with functional and molecular genetic defects of the respiratory chain.
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Affiliation(s)
- J Müller-Höcker
- Pathologisches Institut, Ludwig-Maximilians Universität, München, Germany
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23
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Abstract
Results from quantitative PCR analysis of the frequency of deleted mitochondrial genomes in male Fischer 344 rats reveal an age-related rise in this molecular abnormality. We used this model to examine the ability of dietary restriction (DR) to prevent this potentially pathogenic change. DR prevented age-related increase in frequency of mitochondrial deletions in the liver. In contrast, however, DR had no effect on the age-related increase in deletion frequency in the brain. These data suggest that the effects of DR on age-related accumulation of mitochondrial DNA deletions may be tissue specific.
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Affiliation(s)
- C M Kang
- Department of Physiology, University of Texas Health Science Center, San Antonio 78284-7756, USA
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24
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Melov S, Hinerfeld D, Esposito L, Wallace DC. Multi-organ characterization of mitochondrial genomic rearrangements in ad libitum and caloric restricted mice show striking somatic mitochondrial DNA rearrangements with age. Nucleic Acids Res 1997; 25:974-82. [PMID: 9023106 PMCID: PMC146531 DOI: 10.1093/nar/25.5.974] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Mitochondrial DNA (mtDNA) rearrangements have been shown to accumulate with age in the post-mitotic tissues of a variety of animals and have been hypothesized to result in the age-related decline of mitochondrial bioenergetics leading to tissue and organ failure. Caloric restriction in rodents has been shown to extend life span supporting an association between bioenergetics and senescence. In the present study, we use full length mtDNA amplification by long-extension polymerase chain reaction (LX-PCR) to demonstrate that mice accumulate a wide variety of mtDNA rearrangements with age in post mitotic tissues. Similarly, using an alternative PCR strategy, we have found that 2-4 kb minicircles containing the origin of heavy-strand replication accumulate with age in heart but not brain. Analysis of mtDNA structure and conformation by Southern blots of unrestricted DNA resolved by field inversion gel electrophoresis have revealed that the brain mtDNAs of young animals contain the traditional linear, nicked, and supercoiled mtDNAs while old animals accumulate substantial levels of a slower migrating species we designate age-specific mtDNAs. In old caloric restricted animals, a wide variety of rearranged mtDNAs can be detected by LX-PCR in post mitotic tissues, but Southern blots of unrestricted DNA reveals a marked reduction in the levels of the age- specific mtDNA species. These observations confirm that mtDNA mutations accumulate with age in mice and suggest that caloric restriction impedes this progress.
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Affiliation(s)
- S Melov
- Center for Genetics and Molecular Medicine, 1462 Clifton Rd., Emory University, Atlanta, GA 30322, USA
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25
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Zhang C, Bills M, Quigley A, Maxwell RJ, Linnane AW, Nagley P. Varied prevalence of age-associated mitochondrial DNA deletions in different species and tissues: a comparison between human and rat. Biochem Biophys Res Commun 1997; 230:630-5. [PMID: 9015375 DOI: 10.1006/bbrc.1996.6020] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The prevalence in tissues of mtDNA deletions was compared by PCR between humans and rats of similar "biological ages". Pairs of species-specific primers were used which spanned similar portions of the human and rat mtDNA genomes. There were much fewer PCR products amplified from rat mtDNA than from human mtDNA in each of the three tissues initially analysed: heart, liver and skeletal muscle. By contrast, many more PCR products were amplified from rat kidney than from human kidney. Therefore, while there were far more deletions in heart, liver and skeletal muscle of humans than in corresponding rat tissues, the prevalence of mtDNA deletions was markedly less in human kidney than in rat kidney. The data also indicate that human kidney contains less mtDNA deletions than heart, liver and skeletal muscle in humans; whereas in rat kidney there are more mtDNA deletions than in those three tissues of rat. It is further suggested that, when utilising rodents as experimental models for human ageing, the appropriate tissues should be considered, since not all tissues of rats accumulate mtDNA mutations in the same manner as those of humans.
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Affiliation(s)
- C Zhang
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.
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26
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Abstract
Age-associated alterations of the mitochondrial genome occur in several different species; however, their physiological relevance remains unclear. The age-associated changes of mitochondrial DNA (mtDNA) include nucleotide point mutations and modifications, as well as deletions. In this review, we summarize the current literature on age-associated mtDNA mutations and deletions and comment on their abundance. A clear need exists for a more thorough evaluation of the total damage to the mitochondrial genome that accumulates in aged tissues.
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Affiliation(s)
- C M Lee
- Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison 53706, USA
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27
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Gudikote JP, Van Tuyle GC. Rearrangements in the shorter arc of rat mitochondrial DNA involving the region of the heavy and light strand promoters. Mutat Res 1996; 356:275-86. [PMID: 8841497 DOI: 10.1016/0027-5107(96)00073-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Brain mtDNA from rats ranging in age from 1 day to 33 months were analyzed for large-scale rearrangements using nested PCR. The region of the mtDNA targeted by the primers was the shorter are between the two origins of replication and encompassed the heavy (H) and light (L) strand promoters (HSP) and (LSP). Rearrangements lacking 4 to 5 kb of genomic sequence were found in animals of all ages. Twenty-two different rearrangements were sequenced; two of these were found replicated in several different animals. All the rearrangements identified lacked an HSP and six lacked an LSP as well. The end points of each rearrangement had short direct repeats of 9 bp or less, but repeats of 4 bp or less were the most common. The mode of involvement of the direct repeats in the rearrangement mechanism varied since in some cases a sequence precisely equivalent to one member of the paired repeats was found at the junction; whereas in other cases, more or less than one complete member was found. Sixteen of the 22 rearrangements terminated on one side within a 22-bp locus, or hot spot, located at a potential stem-loop structure midway between the HSP and LSP. The other ends of these rearrangements were at different sites. In addition, a secondary hot spot was found near the junction between the tRNA(Ala) and tRNA(Asn) genes, which lie in a cluster of five tRNA genes that surround the stem-loop structure of the L-strand origin of replication. The data suggest a link between secondary structure and short direct repeats and the rearrangement mechanism(s). The results of this study, in conjunction with out previous study of the longer arc of rat mtDNA (Van Tuyle, G.C., J.P. Gudikote, V.H. Hurt, B.B. Miller and C.A. Moore (1996) Multiple, Large deletions in rat mitochondrial DNA: Evidence for a major hot spot, Mutation Res., 349, 95-107), indicate that nearly the entire mitochondrial genome is subject to rearrangement mutations that are detectable in brain tissue throughout an animal's life span.
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MESH Headings
- Age Factors
- Animals
- Base Sequence
- Brain/cytology
- Cloning, Molecular
- DNA, Mitochondrial/genetics
- DNA, Mitochondrial/ultrastructure
- Electrophoresis, Agar Gel
- Gene Rearrangement
- Molecular Sequence Data
- Polymerase Chain Reaction
- Promoter Regions, Genetic
- RNA, Transfer, Ala/genetics
- RNA, Transfer, Asn/genetics
- Rats
- Rats, Inbred F344
- Rats, Sprague-Dawley
- Repetitive Sequences, Nucleic Acid
- Transcription, Genetic
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Affiliation(s)
- J P Gudikote
- Department of Biochemistry and Molecular Biophysics, Virginia Commonwealth University, Richmond 23298-0614, USA
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28
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Müller-Höcker J, Schäfer S, Link TA, Possekel S, Hammer C. Defects of the respiratory chain in various tissues of old monkeys: a cytochemical-immunocytochemical study. Mech Ageing Dev 1996; 86:197-213. [PMID: 8733113 DOI: 10.1016/0047-6374(95)01692-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The aim of the present study was to evaluate if defects of the respiratory chain known to occur in humans, also exist in lower primates. Cytochemical-immunocytochemical studies of the respiratory chain enzymes in five monkeys (10-25 years of age) showed defects of ubiquinone cytochrome-c-oxidoreductase (complex III), of cytochrome-c-oxidase (complex IV) and of ATP-synthase (complex V) in the limb muscles, diaphragm, heart muscle and extraocular muscles of three old animals (about 25 years) and also in the heart muscle of two younger animals (10 and 15 years). Characteristically, the defects were randomly distributed and there was no loss of succinate-dehydrogenase (complex II) in the fibres. Ultracytochemistry-immunocytochemistry of complex IV disclosed that in an involved fibre segment all the mitochondria exhibited the defect. The highest number of defects was observed in the extraocular muscle (up to 340/cm2) while the lowest defect density was present in the limb muscles (2-5/cm2). Defects of complex IV occurred two to three times more often than defects of complex III and besides isolated defects of complex III and IV, combined defects of both complexes were also observed. Defects of complex V occurred exclusively in combination and were rarely seen. Using subunit specific antisera against complex IV, it could be demonstrated at light and electron microscopic level that loss of activity of cytochrome-c-oxidase was associated with a loss both of mitochondrially and nuclearly coded subunits of the enzyme. In summary, aging in lower primates and humans is characterised by a highly similar defect expression of the respiratory chain enzymes, with intercellular and interorgan differences of the aging process, underlining the universal nature of the involved pathogenetic mechanisms.
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Affiliation(s)
- J Müller-Höcker
- Pathologisches Institut der Ludwig-Maximilians-Universität, München, Germany
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29
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Affiliation(s)
- W C Orr
- Department of Biological Sciences, Southern Methodist University, Dallas, Texas 75275, USA
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30
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Eimon PM, Chung SS, Lee CM, Weindruch R, Aiken JM. Age-associated mitochondrial DNA deletions in mouse skeletal muscle: comparison of different regions of the mitochondrial genome. DEVELOPMENTAL GENETICS 1996; 18:107-13. [PMID: 8934872 DOI: 10.1002/(sici)1520-6408(1996)18:2<107::aid-dvg3>3.0.co;2-d] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The abundance of mitochondrial DNA (mtDNA) deletions has been shown to increase with age in a number of species and may contribute to the aging process. Estimating the total mtDNA deletion load of an individual is essential in evaluating the potential physiological impact. In this study, we compared three 5-kb regions of the mitochondrial genome: one in the major arc, one in the minor arc, and a third containing the light strand origin of replication. Through PCR analysis of mouse skeletal muscle, we have determined that not all regions produce equal numbers of age-associated deletions. There are, on average, twofold more detectable deletions in the major arc region than in the minor arc region. Deletions that result in the loss of the light strand origin of replication are rarely detected. Furthermore, the mechanism of deletion formation seems to be similar in both the major and minor arcs, with direct repeats playing an important, although not essential, role.
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Affiliation(s)
- P M Eimon
- Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison 53706, USA
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31
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Melov S, Shoffner JM, Kaufman A, Wallace DC. Marked increase in the number and variety of mitochondrial DNA rearrangements in aging human skeletal muscle. Nucleic Acids Res 1995; 23:4122-6. [PMID: 7479075 PMCID: PMC307353 DOI: 10.1093/nar/23.20.4122] [Citation(s) in RCA: 209] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Several reports have shown that individual mitochondrial DNA (mtDNA) deletions accumulate with age. However, the overall extent of somatic mtDNA damage with age remains unclear. We have utilized full-length PCR to concurrently screen for multiple mtDNA rearrangements in total DNA extracted from skeletal muscle derived from physiologically normal individuals (n = 35). This revealed that both the number and variety of mtDNA rearrangements increases dramatically between young and old individuals (P < 0.0001). We further examined the mtDNA from both the younger and older subjects by Southern blot analysis and observed an age-related increase in mtDNA(s) comparable in size to mtDNA products unique to patients with known mtDNA deletions. These data imply that a wide spectrum of mtDNA rearrangements accumulate in old individuals, which correlates with the marked age related decrease in OXPHOS capacity observed in post-mitotic tissues.
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Affiliation(s)
- S Melov
- Department of Genetics and Molecular Medicine, School of Medicine, Emory University, Atlanta, GA 30322, USA
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32
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Tanhauser SM, Laipis PJ. Multiple deletions are detectable in mitochondrial DNA of aging mice. J Biol Chem 1995; 270:24769-75. [PMID: 7559594 DOI: 10.1074/jbc.270.42.24769] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Mutational damage to human mitochondrial DNA (mtDNA) can cause disorders in oxidative phosphorylation; speculation that such damage is involved in degenerative diseases and aging is common. We have detected deletions in mouse mtDNA which resemble those found in elderly humans or patients with certain mtDNA disorders. Five different mtDNA deletions, predicted from the positions of short, direct DNA repeats, were present in aged, but not young, mice. Deleted regions were surrounded by either exact or inexact repeats and occurred in both the major and minor regions of the mtDNA genome. The abundance of a particular deletion was generally related to the thermodynamic stability of the bounding repeat sequence. Deletions in aged mice were present at low levels (less than 0.01% of total mtDNA). However, in contrast to results from aged humans, deletions were more abundant in liver than in brain, heart, or skeletal muscle. These results make it possible to predict the location and relative abundance of deletions in any sequenced mtDNA, including inbred mouse strains differing in inherent natural lifespan. The inbred mouse model will allow a critical examination of the relationship between the presence and abundance of mtDNA deletions and the aging process.
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Affiliation(s)
- S M Tanhauser
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville 32610, USA
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33
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Schwarze SR, Lee CM, Chung SS, Roecker EB, Weindruch R, Aiken JM. High levels of mitochondrial DNA deletions in skeletal muscle of old rhesus monkeys. Mech Ageing Dev 1995; 83:91-101. [PMID: 8569289 DOI: 10.1016/0047-6374(95)01611-3] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Mitochondrial DNA (mtDNA) deletions increase in abundance with age in many tissues, however, their calculated low levels (usually < 0.1%) in samples from tissue homogenates containing thousands of cells argue against physiologic significance. Through the analysis of defined numbers of cells (skeletal muscle fibers) from rhesus monkeys, we report that the calculated abundance of specific mtDNA deletions is dependent upon the number of fibers analyzed: as the number of fibers decreases, the calculated deletion abundance increases. Also, most mtDNA deletions appear to occur in a mosaic pattern, varying from cell to cell in size, number and abundance. These data support the hypothesis that mtDNA deletions can focally accumulate to high levels contributing to declines in mass and function of aging skeletal muscle.
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Affiliation(s)
- S R Schwarze
- Department of Animal Health and Biomedical Sciences, University of Wisconsin-Madison 53706, USA
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34
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Lee CM, Eimon P, Weindruch R, Aiken JM. Direct repeat sequences are not required at the breakpoints of age-associated mitochondrial DNA deletions in rhesus monkeys. Mech Ageing Dev 1994; 75:69-79. [PMID: 9128755 DOI: 10.1016/0047-6374(94)90029-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The large majority of mitochondrial DNA (mtDNA) deletions analyzed from mitochondrial myopathies and aging humans have been found to be flanked by direct repeats, a finding which has led to the slip-replication hypothesis of deletion formation. In this study, we have characterized 13 mtDNA deletion breakpoints from skeletal muscle harvested from 9- to 27-year-old rhesus monkeys. Seven of the deletions, five of which were unique to a particular animal, did not have direct repeats at the deletion breakpoints. In contrast, two of the three deletions common to several animals had direct repeats flanking the breakpoints. It appears, therefore, that at least two different mechanisms exist by which mtDNA deletions are formed during aging, one requiring and one independent of flanking direct repeats. Furthermore, the species in which mtDNA deletions are detected may determine which mechanism predominates.
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Affiliation(s)
- C M Lee
- Department of Animal Health and Biomedical Sciences, University of Wisconsin-Madison 53706, USA
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