101
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Chan SSL. Inherited mitochondrial genomic instability and chemical exposures. Toxicology 2017; 391:75-83. [PMID: 28756246 DOI: 10.1016/j.tox.2017.07.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 06/12/2017] [Accepted: 07/24/2017] [Indexed: 12/21/2022]
Abstract
There are approximately 1500 proteins that are needed for mitochondrial structure and function, most of which are encoded in the nuclear genome (Calvo et al., 2006). Each mitochondrion has its own genome (mtDNA), which in humans encodes 13 polypeptides, 22 tRNAs and 2 rRNAs required for oxidative phosphorylation. The mitochondrial genome of humans and most vertebrates is approximately 16.5kbp, double-stranded, circular, with few non-coding bases. Thus, maintaining mtDNA stability, that is, the ability of the cell to maintain adequate levels of mtDNA template for oxidative phosphorylation is essential and can be impacted by the level of mtDNA mutation currently within the cell or mitochondrion, but also from errors made during normal mtDNA replication, defects in mitochondrial quality control mechanisms, and exacerbated by exposures to exogenous and/or endogenous genotoxic agents. In this review, we expand on the origins and consequences of mtDNA instability, the current state of research regarding the mechanisms by which mtDNA instability can be overcome by cellular and chemical interventions, and the future of research and treatments for mtDNA instability.
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Affiliation(s)
- Sherine S L Chan
- Drug Discovery and Biomedical Sciences, College of Pharmacy, Medical University of South Carolina, Charleston, SC 29425, United States; Neuroene Therapeutics, Mt. Pleasant, SC 29464, United States.
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102
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Lee-Barthel A, Baar K, West DWD. Treatment of Ligament Constructs with Exercise-conditioned Serum: A Translational Tissue Engineering Model. J Vis Exp 2017. [PMID: 28654031 PMCID: PMC5608388 DOI: 10.3791/55339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
In vitro experiments are essential to understand biological mechanisms; however, the gap between monolayer tissue culture and human physiology is large, and translation of findings is often poor. Thus, there is ample opportunity for alternative experimental approaches. Here we present an approach in which human cells are isolated from human anterior cruciate ligament tissue remnants, expanded in culture, and used to form engineered ligaments. Exercise alters the biochemical milieu in the blood such that the function of many tissues, organs and bodily processes are improved. In this experiment, ligament construct culture media was supplemented with experimental human serum that has been 'conditioned' by exercise. Thus the intervention is more biologically relevant since an experimental tissue is exposed to the full endogenous biochemical milieu, including binding proteins and adjunct compounds that may be altered in tandem with the activity of an unknown agent of interest. After treatment, engineered ligaments can be analyzed for mechanical function, collagen content, morphology, and cellular biochemistry. Overall, there are four major advantages versus traditional monolayer culture and animal models, of the physiological model of ligament tissue that is presented here. First, ligament constructs are three-dimensional, allowing for mechanical properties (i.e., function) such as ultimate tensile stress, maximal tensile load, and modulus, to be quantified. Second, the enthesis, the interface between boney and sinew elements, can be examined in detail and within functional context. Third, preparing media with post-exercise serum allows for the effects of the exercise-induced biochemical milieu, which is responsible for the wide range of health benefits of exercise, to be investigated in an unbiased manner. Finally, this experimental model advances scientific research in a humane and ethical manner by replacing the use of animals, a core mandate of the National Institutes of Health, the Center for Disease Control, and the Food and Drug Administration.
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Affiliation(s)
- Ann Lee-Barthel
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis
| | - Keith Baar
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis; Department of Physiology and Membrane Biology, University of California, Davis;
| | - Daniel W D West
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis; Faculty of Kinesiology and Physical Education, University of Toronto
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103
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Boengler K, Kosiol M, Mayr M, Schulz R, Rohrbach S. Mitochondria and ageing: role in heart, skeletal muscle and adipose tissue. J Cachexia Sarcopenia Muscle 2017; 8:349-369. [PMID: 28432755 PMCID: PMC5476857 DOI: 10.1002/jcsm.12178] [Citation(s) in RCA: 261] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 10/23/2016] [Accepted: 11/24/2016] [Indexed: 12/11/2022] Open
Abstract
Age is the most important risk factor for most diseases. Mitochondria play a central role in bioenergetics and metabolism. In addition, several lines of evidence indicate the impact of mitochondria in lifespan determination and ageing. The best-known hypothesis to explain ageing is the free radical theory, which proposes that cells, organs, and organisms age because they accumulate reactive oxygen species (ROS) damage over time. Mitochondria play a central role as the principle source of intracellular ROS, which are mainly formed at the level of complex I and III of the respiratory chain. Dysfunctional mitochondria generating less ATP have been observed in various aged organs. Mitochondrial dysfunction comprises different features including reduced mitochondrial content, altered mitochondrial morphology, reduced activity of the complexes of the electron transport chain, opening of the mitochondrial permeability transition pore, and increased ROS formation. Furthermore, abnormalities in mitochondrial quality control or defects in mitochondrial dynamics have also been linked to senescence. Among the tissues affected by mitochondrial dysfunction are those with a high-energy demand and thus high mitochondrial content. Therefore, the present review focuses on the impact of mitochondria in the ageing process of heart and skeletal muscle. In this article, we review different aspects of mitochondrial dysfunction and discuss potential therapeutic strategies to improve mitochondrial function. Finally, novel aspects of adipose tissue biology and their involvement in the ageing process are discussed.
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Affiliation(s)
- Kerstin Boengler
- Institute of Physiology, Justus Liebig University Giessen, Aulweg 129, 35392, Giessen, Germany
| | - Maik Kosiol
- Institute of Physiology, Justus Liebig University Giessen, Aulweg 129, 35392, Giessen, Germany
| | - Manuel Mayr
- King's British Heart Foundation Centre, King's College London, 125 Coldharbour Lane, London, SE5 9NU, UK
| | - Rainer Schulz
- Institute of Physiology, Justus Liebig University Giessen, Aulweg 129, 35392, Giessen, Germany
| | - Susanne Rohrbach
- Institute of Physiology, Justus Liebig University Giessen, Aulweg 129, 35392, Giessen, Germany
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104
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Clark A, Mach N. The Crosstalk between the Gut Microbiota and Mitochondria during Exercise. Front Physiol 2017; 8:319. [PMID: 28579962 PMCID: PMC5437217 DOI: 10.3389/fphys.2017.00319] [Citation(s) in RCA: 200] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 05/03/2017] [Indexed: 12/16/2022] Open
Abstract
Many physiological changes occur in response to endurance exercise in order to adapt to the increasing energy needs, mitochondria biogenesis, increased reactive oxygen species (ROS) production and acute inflammatory responses. Mitochondria are organelles within each cell that are crucial for ATP production and are also a major producer of ROS and reactive nitrogen species during intense exercise. Recent evidence shows there is a bidirectional interaction between mitochondria and microbiota. The gut microbiota have been shown to regulate key transcriptional co-activators, transcription factors and enzymes involved in mitochondrial biogenesis such as PGC-1α, SIRT1, and AMPK genes. Furthermore, the gut microbiota and its metabolites, such as short chain fatty acids and secondary bile acids, also contribute to host energy production, ROS modulation and inflammation in the gut by attenuating TNFα- mediated immune responses and inflammasomes such as NLRP3. On the other hand, mitochondria, particularly mitochondrial ROS production, have a crucial role in regulating the gut microbiota via modulating intestinal barrier function and mucosal immune responses. Recently, it has also been shown that genetic variants within the mitochondrial genome, could affect mitochondrial function and therefore the intestinal microbiota composition and activity. Diet is also known to dramatically modulate the composition of the gut microbiota. Therefore, studies targeting the gut microbiota can be useful for managing mitochondrial related ROS production, pro-inflammatory signals and metabolic limits in endurance athletes.
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Affiliation(s)
- Allison Clark
- Health Science Department, Open University of CataloniaBarcelona, Spain
| | - Núria Mach
- Health Science Department, Open University of CataloniaBarcelona, Spain.,UMR 1313, INRA, AgroParisTech, Université Paris-SaclayJouy-en-Josas, France
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105
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Zhang YF, Wang JT, Gao JB, Lyu YY, Liang JM, Jia FY, Chen YB, Hao YP. [Alpers-Huttenlocher syndrome caused by a novel compound heterozygous mutation of POLG gene: a case report]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2017; 19:498-501. [PMID: 28506336 PMCID: PMC7389134 DOI: 10.7499/j.issn.1008-8830.2017.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Accepted: 10/11/2016] [Indexed: 06/07/2023]
Affiliation(s)
- Yan-Feng Zhang
- Department of Pediatric Neurology, First Hospital of Jilin University, Changchun 130021, China
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106
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Gamu D, Trinh A, Fajardo VA, Bombardier E, Tupling AR. Sarcolipin expression is not required for the mitochondrial enzymatic response to physical activity or diet. J Appl Physiol (1985) 2017; 122:1276-1283. [PMID: 28183820 DOI: 10.1152/japplphysiol.00833.2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 02/06/2017] [Accepted: 02/06/2017] [Indexed: 11/22/2022] Open
Abstract
In mice, transgenic manipulation of Ca2+-handling proteins is sufficient to alter the metabolic phenotype of muscle. We have previously shown that ablation of sarcolipin (SLN), a regulatory protein and uncoupler of sarco(endo)plasmic reticulum Ca2+-ATPases, leads to excessive diet-induced obesity and glucose intolerance in mice. However, it is unclear how loss of SLN per se affects muscle oxidative capacity and the ability of mitochondria to adapt to physiological stimuli, such as exercise training or calorie overload. To address this question, Sln-/- and wild-type (WT) littermates were given access to voluntary running wheels or underwent a treadmill training protocol for 8 wk. Furthermore, a separate group of mice were given a high-fat diet (42% kcal from fat for 8 wk) to determine whether the excessively obese phenotype of Sln-/- mice is associated with altered oxidative capacity. While voluntary running was insufficient to elicit mitochondrial adaptations, treadmill-trained mice showed significant increases (P < 0.05) in the maximal activities of succinate dehydrogenase (+11%), citrate synthase (+12%), cytochrome oxidase (COX: +17%), along with increased protein expression of cytochrome c (+34%) and COX IV (+28%), which were irrespective of SLN expression. Lastly, no changes in the activities of mitochondrial marker enzymes existed with high-fat feeding, regardless of genotype. Together, these findings indicate that SLN is not required for the regulation of oxidative capacity in response to physiological stress, namely exercise or caloric surfeit.NEW & NOTEWORTHY Sarcolipin (SLN) has gained considerable attention for its uncoupling role of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA). Because of SLN's ability to alter both cellular energy use and cytosolic [Ca2+], the potential exists for a regulatory role of mitochondrial biogenesis. Herein, we show skeletal muscle oxidative capacity to be unaltered in mice lacking SLN following exercise training or high-fat feeding. Our results contrast with published studies of SLN-overexpressing mice, possibly owing to supraphysiological uncoupling of SERCA.
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Affiliation(s)
- Daniel Gamu
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Anton Trinh
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Val A Fajardo
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Eric Bombardier
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - A Russell Tupling
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
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107
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DNA damage-dependent mechanisms of ageing and disease in the macro- and microvasculature. Eur J Pharmacol 2017; 816:116-128. [PMID: 28347738 DOI: 10.1016/j.ejphar.2017.03.050] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 03/07/2017] [Accepted: 03/23/2017] [Indexed: 12/15/2022]
Abstract
A decline in the function of the macro- and micro-vasculature occurs with ageing. DNA damage also accumulates with ageing, and thus DNA damage and repair have important roles in physiological ageing. Considerable evidence also supports a crucial role for DNA damage in the development and progression of macrovascular disease such as atherosclerosis. These findings support the concept that prolonged exposure to risk factors is a major stimulus for DNA damage within the vasculature, in part via the generation of reactive oxygen species. Genomic instability can directly affect vascular cellular function, leading to cell cycle arrest, apoptosis and premature vascular cell senescence. In contrast, the study of age-related impaired function and DNA damage mechanisms in the microvasculature is limited, although ageing is associated with microvessel endothelial dysfunction. This review examines current knowledge on the role of DNA damage and DNA repair systems in macrovascular disease such as atherosclerosis and microvascular disease. We also discuss the cellular responses to DNA damage to identify possible strategies for prevention and treatment.
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108
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Mitochondrial-Targeted Catalase: Extended Longevity and the Roles in Various Disease Models. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 146:203-241. [PMID: 28253986 DOI: 10.1016/bs.pmbts.2016.12.015] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The free-radical theory of aging was proposed more than 50 years ago. As one of the most popular mechanisms explaining the aging process, it has been extensively studied in several model organisms. However, the results remain controversial. The mitochondrial version of free-radical theory of aging proposes that mitochondria are both the primary sources of reactive oxygen species (ROS) and the primary targets of ROS-induced damage. One critical ROS is hydrogen peroxide, which is naturally degraded by catalase in peroxisomes or glutathione peroxidase within mitochondria. Our laboratory developed mice-overexpressing catalase targeted to mitochondria (mCAT), peroxisomes (pCAT), or the nucleus (nCAT) in order to investigate the role of hydrogen peroxide in different subcellular compartments in aging and age-related diseases. The mCAT mice have demonstrated the largest effects on life span and healthspan extension. This chapter will discuss the mCAT phenotype and review studies using mCAT to investigate the roles of mitochondrial oxidative stresses in various disease models, including metabolic syndrome and atherosclerosis, cardiac aging, heart failure, skeletal muscle pathology, sensory defect, neurodegenerative diseases, and cancer. As ROS has been increasingly recognized as essential signaling molecules that may be beneficial in hormesis, stress response and immunity, the potential pleiotropic, or adverse effects of mCAT are also discussed. Finally, the development of small-molecule mitochondrial-targeted therapeutic approaches is reviewed.
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109
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Someya S, Kujoth GC, Kim MJ, Hacker TA, Vermulst M, Weindruch R, Prolla TA. Effects of calorie restriction on the lifespan and healthspan of POLG mitochondrial mutator mice. PLoS One 2017; 12:e0171159. [PMID: 28158260 PMCID: PMC5291490 DOI: 10.1371/journal.pone.0171159] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 01/16/2017] [Indexed: 01/21/2023] Open
Abstract
Mitochondrial DNA (mtDNA) mutations are thought to have a causative role in age-related pathologies. We have shown previously that mitochondrial mutator mice (PolgD257A/D257A), harboring a proofreading-deficient version of the mtDNA polymerase gamma (POLG), accumulate mtDNA mutations in multiple tissues and display several features of accelerated aging. Calorie restriction (CR) is known to delay the onset of age-related diseases and to extend the lifespan of a variety of species, including rodents. In the current study we investigated the effects of CR on the lifespan and healthspan of mitochondrial mutator mice. Long-term CR did not increase the median or maximum lifespan of PolgD257A/D257A mice. Furthermore, CR did not reduce mtDNA deletions in the heart and muscle, accelerated sarcopenia, testicular atrophy, nor improve the alterations in cardiac parameters that are present in aged mitochondrial mutator mice. Therefore, our findings suggest that accumulation of mtDNA mutations may interfere with the beneficial action of CR in aging retardation.
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Affiliation(s)
- Shinichi Someya
- Department of Aging and Geriatric Research, University of Florida, Gainesville, Florida, United States of America
| | - Gregory C. Kujoth
- Department of Neurological Surgery, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Mi-Jung Kim
- Department of Aging and Geriatric Research, University of Florida, Gainesville, Florida, United States of America
| | - Timothy A. Hacker
- Department of Medicine, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Marc Vermulst
- Center for Mitochondrial and Epigenomic Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Richard Weindruch
- Veterans Administration Hospital, Geriatric Research, Education and Clinical Center, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Tomas A. Prolla
- Departments of Genetics & Medical Genetics, University of Wisconsin, Madison, Wisconsin, United States of America
- * E-mail:
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110
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Abreu P, Leal-Cardoso JH, Ceccatto VM. ADAPTAÇÃO DO MÚSCULO ESQUELÉTICO AO EXERCÍCIO FÍSICO: CONSIDERAÇÕES MOLECULARES E ENERGÉTICAS. REV BRAS MED ESPORTE 2017. [DOI: 10.1590/1517-869220172301167371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
RESUMO Os benefícios para a saúde e as adaptações fisiológicas ao exercício regular são amplamente conhecidos e, com o advento das ciências ômicas e moleculares, revelou-se uma complexa rede de vias de sinalização e moléculas reguladoras que coordenam a resposta adaptativa do músculo esquelético ao exercício. As mudanças orgânicas transientes, porém, são cumulativas no pós-exercício. Elas incluem, de forma principal, a transcrição de genes relacionados aos fatores regulatórios da miogênese, ao metabolismo de carboidratos, à mobilização de gorduras, ao transporte e oxidação de substratos, ao metabolismo mitocondrial através da fosforilação oxidativa e, por fim, à regulação transcricional de genes envolvidos na biogênese mitocondrial. Tendo em vista o grande impacto científico, resumiram-se neste trabalho, além de algumas das principais respostas moleculares sofridas pelo músculo esquelético com o exercício físico, fatores que coordenam a plasticidade muscular para o ganho de desempenho. Foram citadas dezenas de biomarcadores ligados a alguns aspectos moleculares das adaptações do músculo esquelético ao exercício físico, algumas principais vias sinalizadoras e o papel mitocondrial, revelando alguns novos paradigmas para o entendimento desta área científica.
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111
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DeBalsi KL, Hoff KE, Copeland WC. Role of the mitochondrial DNA replication machinery in mitochondrial DNA mutagenesis, aging and age-related diseases. Ageing Res Rev 2017; 33:89-104. [PMID: 27143693 DOI: 10.1016/j.arr.2016.04.006] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 04/19/2016] [Accepted: 04/19/2016] [Indexed: 12/19/2022]
Abstract
As regulators of bioenergetics in the cell and the primary source of endogenous reactive oxygen species (ROS), dysfunctional mitochondria have been implicated for decades in the process of aging and age-related diseases. Mitochondrial DNA (mtDNA) is replicated and repaired by nuclear-encoded mtDNA polymerase γ (Pol γ) and several other associated proteins, which compose the mtDNA replication machinery. Here, we review evidence that errors caused by this replication machinery and failure to repair these mtDNA errors results in mtDNA mutations. Clonal expansion of mtDNA mutations results in mitochondrial dysfunction, such as decreased electron transport chain (ETC) enzyme activity and impaired cellular respiration. We address the literature that mitochondrial dysfunction, in conjunction with altered mitochondrial dynamics, is a major driving force behind aging and age-related diseases. Additionally, interventions to improve mitochondrial function and attenuate the symptoms of aging are examined.
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Affiliation(s)
- Karen L DeBalsi
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Kirsten E Hoff
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - William C Copeland
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA.
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112
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Niel R, Ayachi M, Mille-Hamard L, Le Moyec L, Savarin P, Clement MJ, Besse S, Launay T, Billat VL, Momken I. A new model of short acceleration-based training improves exercise performance in old mice. Scand J Med Sci Sports 2016; 27:1576-1587. [PMID: 28000342 DOI: 10.1111/sms.12809] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/31/2016] [Indexed: 12/14/2022]
Abstract
In order to identify a more appealing exercise strategy for the elderly, we studied a mouse model to determine whether a less time-consuming training program would improve exercise performance, enzyme activities, mitochondrial respiration, and metabolomic parameters. We compared the effects of short-session (acceleration-based) training with those of long-session endurance training in 23-month-old mice. The short-session training consisted of five acceleration-based treadmill running sessions over 2 weeks (the acceleration group), whereas the endurance training consisted of five-one-hour treadmill sessions per week for 4 weeks (the endurance group). A control group of mice was also studied. In the acceleration group, the post-training maximum running speed and time to exhaustion were significantly improved, relative to pretraining values (+8% for speed, P<.05; +10% for time to exhaustion, P<.01). The post-training maximum running speed was higher in the acceleration group than in the endurance group (by 23%; P<.001) and in the control group (by 15%; P<.05). In skeletal muscle samples, the enzymatic activities of citrate synthase, lactate dehydrogenase, and creatine kinase were significantly higher in the acceleration group than in the endurance group. Furthermore, mitochondrial respiratory activity in the gastrocnemius was higher in the acceleration group than in the control group. A metabolomic urine analysis revealed a higher mean taurine concentration and a lower mean branched amino acid concentration in the acceleration group. In old mice, acceleration-based training appears to be an efficient way of increasing performance by improving both aerobic and anaerobic metabolism, and possibly by enhancing antioxidant defenses and maintaining muscle protein balance.
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Affiliation(s)
- R Niel
- Unité de Biologie Intégrative des Adaptations à l'Exercice (EA7362), Université Evry-Val d'Essonne, Evry, France
| | - M Ayachi
- Unité de Biologie Intégrative des Adaptations à l'Exercice (EA7362), Université Evry-Val d'Essonne, Evry, France
| | - L Mille-Hamard
- Unité de Biologie Intégrative des Adaptations à l'Exercice (EA7362), Université Evry-Val d'Essonne, Evry, France
| | - L Le Moyec
- Unité de Biologie Intégrative des Adaptations à l'Exercice (EA7362), Université Evry-Val d'Essonne, Evry, France
| | - P Savarin
- Laboratoire Chimie, Structures, Propriétés de Biomatériaux et d'Agents Thérapeutiques (CSPBAT), Unité Mixte de Recherche (UMR) 7244, Centre National de Recherche Scientifique (CNRS), Equipe Spectroscopie des Biomolécules et des Milieux Biologiques (SBMB), Université Paris 13, Bobigny, France
| | - M-J Clement
- Laboratoire Structure-Activité des Biomolécules Normales et Pathologiques, INSERM U1204 and Université Evry-Val d'Essonne, Evry, France
| | - S Besse
- Unité de Biologie Intégrative des Adaptations à l'Exercice (EA7362), Université Evry-Val d'Essonne, Evry, France.,Université Paris Descartes, COMUE Sorbonne Paris Cité, Paris, France
| | - T Launay
- Unité de Biologie Intégrative des Adaptations à l'Exercice (EA7362), Université Evry-Val d'Essonne, Evry, France.,Université Paris Descartes, COMUE Sorbonne Paris Cité, Paris, France
| | - V L Billat
- Unité de Biologie Intégrative des Adaptations à l'Exercice (EA7362), Université Evry-Val d'Essonne, Evry, France
| | - I Momken
- Unité de Biologie Intégrative des Adaptations à l'Exercice (EA7362), Université Evry-Val d'Essonne, Evry, France
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113
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von Zglinicki T, Varela-Nieto I, Brites D, Karagianni N, Ortolano S, Georgopoulos S, Cardoso AL, Novella S, Lepperdinger G, Trendelenburg AU, van Os R. Frailty in mouse ageing: A conceptual approach. Mech Ageing Dev 2016; 160:34-40. [DOI: 10.1016/j.mad.2016.07.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 07/11/2016] [Accepted: 07/15/2016] [Indexed: 01/21/2023]
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114
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Kõks S, Dogan S, Tuna BG, González-Navarro H, Potter P, Vandenbroucke RE. Mouse models of ageing and their relevance to disease. Mech Ageing Dev 2016; 160:41-53. [PMID: 27717883 DOI: 10.1016/j.mad.2016.10.001] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 09/26/2016] [Accepted: 10/03/2016] [Indexed: 12/28/2022]
Abstract
Ageing is a process that gradually increases the organism's vulnerability to death. It affects different biological pathways, and the underlying cellular mechanisms are complex. In view of the growing disease burden of ageing populations, increasing efforts are being invested in understanding the pathways and mechanisms of ageing. We review some mouse models commonly used in studies on ageing, highlight the advantages and disadvantages of the different strategies, and discuss their relevance to disease susceptibility. In addition to addressing the genetics and phenotypic analysis of mice, we discuss examples of models of delayed or accelerated ageing and their modulation by caloric restriction.
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Affiliation(s)
- Sulev Kõks
- University of Tartu, Tartu, Estonia and Estonian University of Life Sciences, Tartu, Estonia.
| | - Soner Dogan
- Yeditepe University, School of Medicine, Department of Medical Biology, Istanbul, Turkey.
| | - Bilge Guvenc Tuna
- Yeditepe University, School of Medicine, Department of Biophysics, Istanbul, Turkey.
| | - Herminia González-Navarro
- Institute of Health Research-INCLIVA, 46010 Valencia, Spain and CIBER de Diabetes y Enfermedades Metabólicas (CIBERDEM), 28029 Madrid, Spain.
| | - Paul Potter
- Mammalian Genetics Unit, MRC Harwell, Oxfordshire, UK.
| | - Roosmarijn E Vandenbroucke
- Inflammation Research Center, VIB, Ghent, Belgium, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.
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115
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D'Souza DM, Zhou S, Rebalka IA, MacDonald B, Moradi J, Krause MP, Al-Sajee D, Punthakee Z, Tarnopolsky MA, Hawke TJ. Decreased Satellite Cell Number and Function in Humans and Mice With Type 1 Diabetes Is the Result of Altered Notch Signaling. Diabetes 2016; 65:3053-61. [PMID: 27335233 DOI: 10.2337/db15-1577] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 06/15/2016] [Indexed: 11/13/2022]
Abstract
Type 1 diabetes (T1D) negatively influences skeletal muscle health; however, its effect on muscle satellite cells (SCs) remains largely unknown. SCs from samples from rodents (Akita) and human subjects with T1D were examined to discern differences in SC density and functionality compared with samples from their respective control subjects. Examination of the Notch pathway was undertaken to investigate its role in changes to SC functionality. Compared with controls, Akita mice demonstrated increased muscle damage after eccentric exercise along with a decline in SC density and myogenic capacity. Quantification of components of the Notch signaling pathway revealed a persistent activation of Notch signaling in Akita SCs, which could be reversed with the Notch inhibitor DAPT. Similar to Akita samples, skeletal muscle from human subjects with T1D displayed a significant reduction in SC content, and the Notch ligand, DLL1, was significantly increased compared with control subjects, supporting the dysregulated Notch pathway observed in Akita muscles. These data indicate that persistent activation in Notch signaling impairs SC functionality in the T1D muscle, resulting in a decline in SC content. Given the vital role played by the SC in muscle growth and maintenance, these findings suggest that impairments in SC capacities play a primary role in the skeletal muscle myopathy that characterizes T1D.
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MESH Headings
- Adolescent
- Adult
- Animals
- Cell Count
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Experimental/physiopathology
- Diabetes Mellitus, Type 1/metabolism
- Diabetes Mellitus, Type 1/pathology
- Diabetes Mellitus, Type 1/physiopathology
- Humans
- Intercellular Signaling Peptides and Proteins/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/physiopathology
- Physical Conditioning, Animal/physiology
- Receptors, Notch/metabolism
- Satellite Cells, Skeletal Muscle/cytology
- Satellite Cells, Skeletal Muscle/metabolism
- Satellite Cells, Skeletal Muscle/physiology
- Signal Transduction/physiology
- Young Adult
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Affiliation(s)
- Donna M D'Souza
- Department of Pathology & Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Sarah Zhou
- Department of Pathology & Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Irena A Rebalka
- Department of Pathology & Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Blair MacDonald
- Department of Pathology & Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Jasmin Moradi
- Department of Pathology & Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Matthew P Krause
- Department of Kinesiology, University of Windsor, Windsor, Ontario, Canada
| | - Dhuha Al-Sajee
- Department of Pathology & Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Zubin Punthakee
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
| | - Mark A Tarnopolsky
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
| | - Thomas J Hawke
- Department of Pathology & Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
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Dos Santos CC, Herridge M, Batt J. Early goal directed mobility in the ICU: 'something in the way you move'. J Thorac Dis 2016; 8:E784-7. [PMID: 27620874 DOI: 10.21037/jtd.2016.05.96] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Claudia C Dos Santos
- Keenan and Li Ka Shing Knowledge Institute of St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada;; Department of Medicine and Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada;; Interdepartmental Division of Critical Care, University Health Network, University of Toronto, Ontario, Canada
| | - Margaret Herridge
- Interdepartmental Division of Critical Care, University Health Network, University of Toronto, Ontario, Canada;; Department of Medicine and Department of Occupational Science and Occupational Therapy, University of Toronto, Toronto, Ontario, Canada
| | - Jane Batt
- Keenan and Li Ka Shing Knowledge Institute of St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada;; Department of Medicine and Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
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117
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Safdar A, Saleem A, Tarnopolsky MA. The potential of endurance exercise-derived exosomes to treat metabolic diseases. Nat Rev Endocrinol 2016; 12:504-17. [PMID: 27230949 DOI: 10.1038/nrendo.2016.76] [Citation(s) in RCA: 271] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Endurance exercise-mediated multisystemic adaptations are known to mitigate metabolism-related disorders such as obesity and type 2 diabetes mellitus (T2DM). However, the underlying molecular mechanisms that promote crosstalk between organs and orchestrate the pro-metabolic effects of endurance exercise remain unclear. Exercise-induced release of peptides and nucleic acids from skeletal muscle and other organs (collectively termed 'exerkines') has been implicated in mediating these systemic adaptations. Given that the extracellular milieu is probably not a hospitable environment for labile exerkines, a lipid vehicle-based mode of delivery has originated over the course of evolution. Two types of extracellular vesicles, exosomes and microvesicles, have been shown to contain proteins and nucleic acids that participate in a variety of physiological and pathological processes. Exosomes, in particular, have been shown to facilitate the exchange of peptides, microRNA, mRNA and mitochondrial DNA between cells and tissues. Intriguingly, circulatory extracellular vesicle content increases in an intensity-dependant manner in response to endurance exercise. We propose that the systemic benefits of exercise are modulated by exosomes and/or microvesicles functioning in an autocrine, paracrine and/or endocrine manner. Furthermore, we posit that native or modified exosomes, and/or microvesicles enriched with exerkines will have therapeutic utility in the treatment of obesity and T2DM.
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Affiliation(s)
- Adeel Safdar
- Department of Pediatrics, McMaster University, 1200 Main Street West, Hamilton, Ontario L8N 3Z5, Canada
| | - Ayesha Saleem
- Department of Pediatrics, McMaster University, 1200 Main Street West, Hamilton, Ontario L8N 3Z5, Canada
| | - Mark A Tarnopolsky
- Department of Pediatrics, McMaster University, 1200 Main Street West, Hamilton, Ontario L8N 3Z5, Canada
- Department of Medicine, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4L8, Canada
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118
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deFilippi CR, de Lemos JA, Newman AB, Guralnik JM, Christenson RH, Pahor M, Church T, Espeland M, Krithevsky SB, Stafford R, Seliger SL. Impact of moderate physical activity on the longitudinal trajectory of a cardiac specific biomarker of injury: Results from a randomized pilot study of exercise intervention. Am Heart J 2016; 179:151-6. [PMID: 27595690 DOI: 10.1016/j.ahj.2016.07.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Accepted: 07/08/2016] [Indexed: 12/21/2022]
Abstract
BACKGROUND In animal models, physical activity (PA) prevents cardiac myocyte cell death. Data for PA mitigating myocyte injury in humans are limited to observational studies. Using a randomized controlled trial design, we sought to determine if introducing moderate PA to previously sedentary older adults could reduce the trajectory of myocardial injury as measured by the high-sensitive cardiac troponin T (hs-cTnT) assay. METHODS Participants (age ≥70 years) were assigned to a 1-year intervention of moderate PA or health education control. High-sensitive cTnT was measured at baseline and 1 year in the 307 of 424 subjects who had available stored serum. Changes in hs-cTnT within 1 year were compared between PA and control groups, as were differences in the proportion of subjects with a significant rise in hs-cTnT (prospectively defined as a>50% increase at follow-up from baseline). Moderate to vigorous PA in kcal/wk was estimated with the CHAMPS questionnaire. RESULTS Baseline hs-cTnT levels and PA kcal/wk were similar for both groups. Activity kcal/wk increased in the PA, but not in the control group at 1 year. The median increase in hs-cTnT level from baseline was >3 times larger in the control (0.73 ng/L, interquartile range -0.64 to 2.59) vs the PA group (0.19ng/L, interquartile range -1.10 to 1.93) (P=.02). The proportion with a>50% increase in hs-cTnT was larger in the control group than in the PA group (9.3% vs 5.1%), but this difference was not statistically significant (P=.16). CONCLUSIONS Initiation of moderate PA in sedentary older adults may favorably modify subclinical myocardial injury.
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119
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Abstract
Hormesis is a process whereby exposure to a low dose of a potentially harmful stressor promotes adaptive changes to the cell that enables it to better tolerate subsequent stress. In recent years this concept has been applied specifically to the mitochondria (mitohormesis), suggesting that in response to a perturbation the mitochondria can initiate and transduce a signal to the nucleus that coordinates a transcriptional response resulting in both mitochondrial and non-mitochondrial adaptations that return and maintain cellular homeostasis. In this review we summarize the evidence that mitohormesis is a significant adaptive-response signaling pathway, and suggest that it plays a role in mediating exercise-induced adaptations. We discuss potential mitochondrial emitters of retrograde signals that may activate known exercise-sensitive transcription factors to modulate transcription responses to exercise, and draw on evidence from mitochondrial dysfunction animal models to support a role for mitohormesis in mitochondrial biogenesis. Studies directly linking mitohormesis to the exercise training response are lacking, however mounting evidence suggests numerous signals are emitted from the mitochondria during exercise and have the potential to induce a nuclear transcription response, with reactive oxygen species (ROS) being the primary candidate.
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Affiliation(s)
- Troy L Merry
- Energy Metabolism Laboratory, Swiss Federal Institute of Technology (ETH), 8603 Zurich, Switzerland.
| | - Michael Ristow
- Energy Metabolism Laboratory, Swiss Federal Institute of Technology (ETH), 8603 Zurich, Switzerland
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120
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Picard M, Wallace DC, Burelle Y. The rise of mitochondria in medicine. Mitochondrion 2016; 30:105-16. [PMID: 27423788 PMCID: PMC5023480 DOI: 10.1016/j.mito.2016.07.003] [Citation(s) in RCA: 300] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 07/04/2016] [Accepted: 07/12/2016] [Indexed: 12/11/2022]
Abstract
Once considered exclusively the cell's powerhouse, mitochondria are now recognized to perform multiple essential functions beyond energy production, impacting most areas of cell biology and medicine. Since the emergence of molecular biology and the discovery of pathogenic mitochondrial DNA defects in the 1980's, research advances have revealed a number of common human diseases which share an underlying pathogenesis involving mitochondrial dysfunction. Mitochondria undergo function-defining dynamic shape changes, communicate with each other, regulate gene expression within the nucleus, modulate synaptic transmission within the brain, release molecules that contribute to oncogenic transformation and trigger inflammatory responses systemically, and influence the regulation of complex physiological systems. Novel mitopathogenic mechanisms are thus being uncovered across a number of medical disciplines including genetics, oncology, neurology, immunology, and critical care medicine. Increasing knowledge of the bioenergetic aspects of human disease has provided new opportunities for diagnosis, therapy, prevention, and in connecting various domains of medicine. In this article, we overview specific aspects of mitochondrial biology that have contributed to - and likely will continue to enhance the progress of modern medicine.
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Affiliation(s)
- Martin Picard
- Department of Psychiatry, Division of Behavioral Medicine, Columbia University Medical Center, New York, NY, USA; Department of Neurology and CTNI, H Houston Merritt Center, Columbia University Medical Center, New York, NY, USA.
| | - Douglas C Wallace
- The Center for Mitochondrial and Epigenomic Medicine, Children's Hospital of Philadelphia and Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yan Burelle
- Faculty of Pharmacy, Université de Montreal, Montreal, QC, Canada
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121
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Kitaoka Y, Nakazato K, Ogasawara R. Combined effects of resistance training and calorie restriction on mitochondrial fusion and fission proteins in rat skeletal muscle. J Appl Physiol (1985) 2016; 121:806-810. [PMID: 27539498 DOI: 10.1152/japplphysiol.00465.2016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 08/12/2016] [Indexed: 02/04/2023] Open
Abstract
Recent studies have demonstrated that resistance exercise leads not only to muscle hypertrophy, but it also improves mitochondrial function. Because calorie restriction (CR) has been suggested as a way to induce mitochondrial biogenesis, we examined the effects of resistance training with or without CR on muscle weight and key mitochondrial parameters in rat skeletal muscle. Four weeks of resistance training (thrice/wk) resulted in increased gastrocnemius muscle weight by 14% in rats fed ad libitum (AL). The degree of muscle-weight increase via resistance training was lower in rats with CR (7.4%). CR showed no effect on phosphorylation of mammalian target of rapamycin (mTOR) signaling proteins rpS6 and ULK1. Our results revealed that CR resulted in elevated levels of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) protein, a known master regulator of mitochondrial biogenesis. Resistance training alone also resulted in increased PGC-1α levels in skeletal muscle. The magnitude of the increase in PGC-1α was similar in rats in both the CR and AL groups. Moreover, we found that resistance training with CR resulted in elevated levels of proteins involved in mitochondrial fusion (Opa1 and Mfn1), and oxidative phosphorylation, whereas there was no effect of CR on the fission-regulatory proteins Fis1 and Drp1. These results indicate that CR attenuates resistance training-induced muscle hypertrophy, and that it may enhance mitochondrial adaptations in skeletal muscle.
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Affiliation(s)
- Yu Kitaoka
- Department of Sports Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Koichi Nakazato
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan; and
| | - Riki Ogasawara
- Department of Sports Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan; Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Nagoya, Japan
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122
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Genomic Integrity Is Favourably Affected by High-Intensity Interval Training in an Animal Model of Early-Stage Chronic Kidney Disease. SPORTS MEDICINE-OPEN 2016; 2:28. [PMID: 27547714 PMCID: PMC4978751 DOI: 10.1186/s40798-016-0055-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 07/26/2016] [Indexed: 02/08/2023]
Abstract
Background Chronic kidney disease (CKD) is an irreversible disease that diminishes length and quality of life. Emerging evidence suggests CKD progression and genomic integrity are inversely and causally related. To reduce health complications related to CKD progression, chronic aerobic exercise is often recommended. To date, appraisals of differing modes of exercise, along with postulations regarding the mechanisms responsible for observed effects, are lacking. In order to examine the ability of aerobic exercise to encourage improvements in genomic integrity, we evaluated the effects of 8 weeks of high-intensity interval training (HIIT; 85 % VO2max), low intensity training (LIT; 45–50 % VO2max), and sedentary behaviour (SED), in an animal model of early-stage CKD. Methods To assess genomic integrity, we examined kidney-specific messenger RNA (mRNA) expression of genes related to genomic repair and stability: Fan1, Mre11a, and telomere length as measured by T/S ratio. Results Following HIIT, mRNA expression of Fan1 was significantly up-regulated, compared to SED (p = 0.026) and T/S ratio was significantly increased, compared to SED (p < 0.001) and LIT (p = 0.002). Conclusions Our results suggest that HIIT is superior to SED and LIT as HIIT beneficially influenced the expression of genes related to genomic integrity.
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123
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Amelioration of premature aging in mtDNA mutator mouse by exercise: the interplay of oxidative stress, PGC-1α, p53, and DNA damage. A hypothesis. Curr Opin Genet Dev 2016; 38:127-132. [PMID: 27497229 DOI: 10.1016/j.gde.2016.06.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 05/25/2016] [Accepted: 06/21/2016] [Indexed: 11/23/2022]
Abstract
The mtDNA mutator mouse lacks the proofreading capacity of the sole mtDNA polymerase, leading to accumulation of somatic mtDNA mutations, and a profound premature aging phenotype including elevated oxidative stress and apoptosis, and reduced mitochondrial function. We have previously reported that endurance exercise alleviates the aging phenotype in the mutator mice, reduces oxidative stress, and enhances mitochondrial biogenesis. Here we summarize our findings, with the emphasis on the central role of p53 in these adaptations. We demonstrate that mtDNA in sedentary and exercised PolG mice carry similar amounts of mutations in muscle, but in addition to that sedentary mice have more non-mutational damage, which is mitigated by exercise. It follows therefore that the profound alleviation of the mtDNA mutator phenotype in muscle by exercise may not require a reduction in mtDNA mutational load, but rather a decrease of mtDNA damage and/or oxidative stress. We further hypothesize that the observed 'alleviation without a reduction of mutational load' implies that the oxidative stress in PolG muscle is maintained, at least in part, by the 'malicious cycle', a hypothetical positive feedback potentially driven by the 'transcriptional mutagenesis', that is the conversion of chemically modified nucleotides into mutant RNA bases by the mitochondrial RNA polymerase.
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124
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Martín-Fernández B, Gredilla R. Mitochondria and oxidative stress in heart aging. AGE (DORDRECHT, NETHERLANDS) 2016; 38:225-238. [PMID: 27449187 PMCID: PMC5061683 DOI: 10.1007/s11357-016-9933-y] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 07/12/2016] [Indexed: 05/06/2023]
Abstract
As average lifespan of humans increases in western countries, cardiac diseases become the first cause of death. Aging is among the most important risk factors that increase susceptibility for developing cardiovascular diseases. The heart has very aerobic metabolism, and is highly dependent on mitochondrial function, since mitochondria generate more than 90 % of the intracellular ATP consumed by cardiomyocytes. In the last few decades, several investigations have supported the relevance of mitochondria and oxidative stress both in heart aging and in the development of cardiac diseases such as heart failure, cardiac hypertrophy, and diabetic cardiomyopathy. In the current review, we compile different studies corroborating this role. Increased mitochondria DNA instability, impaired bioenergetic efficiency, enhanced apoptosis, and inflammation processes are some of the events related to mitochondria that occur in aging heart, leading to reduced cellular survival and cardiac dysfunction. Knowing the mitochondrial mechanisms involved in the aging process will provide a better understanding of them and allow finding approaches to more efficiently improve this process.
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Affiliation(s)
- Beatriz Martín-Fernández
- Department of Physiology, Faculty of Medicine, Complutense University, Plaza Ramon y Cajal s/n, 28040, Madrid, Spain.
| | - Ricardo Gredilla
- Department of Physiology, Faculty of Medicine, Complutense University, Plaza Ramon y Cajal s/n, 28040, Madrid, Spain.
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125
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Abstract
A decline in mitochondrial quality and activity has been associated with normal aging and correlated with the development of a wide range of age-related diseases. Here, we review the evidence that a decline in mitochondria function contributes to aging. In particular, we discuss how mitochondria contribute to specific aspects of the aging process, including cellular senescence, chronic inflammation, and the age-dependent decline in stem cell activity. Signaling pathways regulating the mitochondrial unfolded protein response and mitophagy are also reviewed, with particular emphasis placed on how these pathways might, in turn, regulate longevity. Taken together, these observations suggest that mitochondria influence or regulate a number of key aspects of aging and suggest that strategies directed at improving mitochondrial quality and function might have far-reaching beneficial effects.
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Affiliation(s)
- Nuo Sun
- Center for Molecular Medicine, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA
| | - Richard J Youle
- Biochemistry Section, Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD 20892, USA.
| | - Toren Finkel
- Center for Molecular Medicine, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA.
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126
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Prakash C, Kumar V. Arsenic-induced mitochondrial oxidative damage is mediated by decreased PGC-1α expression and its downstream targets in rat brain. Chem Biol Interact 2016; 256:228-35. [PMID: 27425645 DOI: 10.1016/j.cbi.2016.07.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 06/21/2016] [Accepted: 07/13/2016] [Indexed: 12/30/2022]
Abstract
The present study was carried out to investigate the molecular mechanism of arsenic-induced mitochondrial oxidative damage and its relation to biogenesis in rat brain. Chronic sodium arsenite (25 ppm, orally) administration for 12 weeks decreased mitochondrial complexes activities and mRNA expression of selective complexes subunits. The expression of mitochondrial biogenesis regulator PGC-1α, and its downstream targets NRF-1, NRF-2 and Tfam were decreased significantly both at mRNA and protein levels suggesting impaired biogenesis following chronic arsenic-exposure. In addition to this, protein expression analysis also revealed activation of Bax and caspase-3, leading to translocation of cytochrome c from mitochondria to cytosol suggesting induction of apoptotic pathway under oxidative stress. This was further confirmed by electron microscopy study which depicted morphological changes in mitochondria in terms of altered nuclear and mitochondrial shape and chromatin condensation in arsenic-treated rats. The immunohistochemical studies showed both nuclear and cytosolic localization of NRF-1 and NRF-2 in arsenic-exposed rat brain further suggesting regulatory role of these transcription factors under arsenic neurotoxicity. The results of present study indicate that arsenic-induced mitochondrial oxidative damage is associated with decreased mitochondrial biogenesis in rat brain that may present as important target to reveal the mechanism for arsenic-induced neurotoxicity.
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Affiliation(s)
- Chandra Prakash
- Department of Biochemistry, Maharshi Dayanand University, Rohtak 124001, Haryana, India
| | - Vijay Kumar
- Department of Biochemistry, Maharshi Dayanand University, Rohtak 124001, Haryana, India.
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Diman A, Boros J, Poulain F, Rodriguez J, Purnelle M, Episkopou H, Bertrand L, Francaux M, Deldicque L, Decottignies A. Nuclear respiratory factor 1 and endurance exercise promote human telomere transcription. SCIENCE ADVANCES 2016; 2:e1600031. [PMID: 27819056 PMCID: PMC5087959 DOI: 10.1126/sciadv.1600031] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 06/29/2016] [Indexed: 05/07/2023]
Abstract
DNA breaks activate the DNA damage response and, if left unrepaired, trigger cellular senescence. Telomeres are specialized nucleoprotein structures that protect chromosome ends from persistent DNA damage response activation. Whether protection can be enhanced to counteract the age-dependent decline in telomere integrity is a challenging question. Telomeric repeat-containing RNA (TERRA), which is transcribed from telomeres, emerged as important player in telomere integrity. However, how human telomere transcription is regulated is still largely unknown. We identify nuclear respiratory factor 1 and peroxisome proliferator-activated receptor γ coactivator 1α as regulators of human telomere transcription. In agreement with an upstream regulation of these factors by adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK), pharmacological activation of AMPK in cancer cell lines or in normal nonproliferating myotubes up-regulated TERRA, thereby linking metabolism to telomere fitness. Cycling endurance exercise, which is associated with AMPK activation, increased TERRA levels in skeletal muscle biopsies obtained from 10 healthy young volunteers. The data support the idea that exercise may protect against aging.
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Affiliation(s)
- Aurélie Diman
- de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium
| | - Joanna Boros
- de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium
| | - Florian Poulain
- de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium
| | - Julie Rodriguez
- Institute of Neuroscience, Université catholique de Louvain, Place Pierre de Coubertin 1, 1348 Louvain-la-Neuve, Belgium
| | - Marin Purnelle
- de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium
- Institute of Neuroscience, Université catholique de Louvain, Place Pierre de Coubertin 1, 1348 Louvain-la-Neuve, Belgium
| | - Harikleia Episkopou
- de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium
| | - Luc Bertrand
- Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Avenue Hippocrate 55, 1200 Brussels, Belgium
| | - Marc Francaux
- Institute of Neuroscience, Université catholique de Louvain, Place Pierre de Coubertin 1, 1348 Louvain-la-Neuve, Belgium
| | - Louise Deldicque
- Institute of Neuroscience, Université catholique de Louvain, Place Pierre de Coubertin 1, 1348 Louvain-la-Neuve, Belgium
- Corresponding author. (L.D.); (A.D.)
| | - Anabelle Decottignies
- de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200 Brussels, Belgium
- Corresponding author. (L.D.); (A.D.)
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Cannatà A, Camparini L, Sinagra G, Giacca M, Loffredo FS. Pathways for salvage and protection of the heart under stress: novel routes for cardiac rejuvenation. Cardiovasc Res 2016; 111:142-53. [DOI: 10.1093/cvr/cvw106] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 05/10/2016] [Indexed: 01/07/2023] Open
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Roh J, Rhee J, Chaudhari V, Rosenzweig A. The Role of Exercise in Cardiac Aging: From Physiology to Molecular Mechanisms. Circ Res 2016; 118:279-95. [PMID: 26838314 DOI: 10.1161/circresaha.115.305250] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Aging induces structural and functional changes in the heart that are associated with increased risk of cardiovascular disease and impaired functional capacity in the elderly. Exercise is a diagnostic and therapeutic tool, with the potential to provide insights into clinical diagnosis and prognosis, as well as the molecular mechanisms by which aging influences cardiac physiology and function. In this review, we first provide an overview of how aging impacts the cardiac response to exercise, and the implications this has for functional capacity in older adults. We then review the underlying molecular mechanisms by which cardiac aging contributes to exercise intolerance, and conversely how exercise training can potentially modulate aging phenotypes in the heart. Finally, we highlight the potential use of these exercise models to complement models of disease in efforts to uncover new therapeutic targets to prevent or treat heart disease in the aging population.
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Affiliation(s)
- Jason Roh
- From the Cardiovascular Division (J. Roh, J. Rhee, V.C., A.R.) and Department of Anesthesiology, Critical Care, and Pain Medicine (J. Rhee), Massachusetts General Hospital and Harvard Medical School, Boston
| | - James Rhee
- From the Cardiovascular Division (J. Roh, J. Rhee, V.C., A.R.) and Department of Anesthesiology, Critical Care, and Pain Medicine (J. Rhee), Massachusetts General Hospital and Harvard Medical School, Boston
| | - Vinita Chaudhari
- From the Cardiovascular Division (J. Roh, J. Rhee, V.C., A.R.) and Department of Anesthesiology, Critical Care, and Pain Medicine (J. Rhee), Massachusetts General Hospital and Harvard Medical School, Boston
| | - Anthony Rosenzweig
- From the Cardiovascular Division (J. Roh, J. Rhee, V.C., A.R.) and Department of Anesthesiology, Critical Care, and Pain Medicine (J. Rhee), Massachusetts General Hospital and Harvard Medical School, Boston.
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130
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Burd NA, Tardif N, Rooyackers O, van Loon LJC. Optimizing the measurement of mitochondrial protein synthesis in human skeletal muscle. Appl Physiol Nutr Metab 2016; 40:1-9. [PMID: 25494678 DOI: 10.1139/apnm-2014-0211] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The measurement of mitochondrial protein synthesis after food ingestion, contractile activity, and/or disease is often used to provide insight into skeletal muscle adaptations that occur in the longer term. Studies have shown that protein ingestion stimulates mitochondrial protein synthesis in human skeletal muscle. Minor differences in the stimulation of mitochondrial protein synthesis occur after a single bout of resistance or endurance exercise. There appear to be no measurable differences in mitochondrial protein synthesis between critically ill patients and aged-matched controls. However, the mitochondrial protein synthetic response is reduced at a more advanced age. In this paper, we discuss the challenges involved in the measurement of human skeletal muscle mitochondrial protein synthesis rates based on stable isotope amino acid tracer methods. Practical guidelines are discussed to improve the reliability of the measurement of mitochondrial protein synthesis rates. The value of the measurement of mitochondrial protein synthesis after a single meal or exercise bout on the prediction of the longer term skeletal muscle mass and performance outcomes in both the healthy and disease populations requires more work, but we emphasize that the measurements need to be reliable to be of any value to the field.
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Affiliation(s)
- Nicholas A Burd
- a Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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131
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Narasimhan M, Rajasekaran NS. Exercise, Nrf2 and Antioxidant Signaling in Cardiac Aging. Front Physiol 2016; 7:241. [PMID: 27378947 PMCID: PMC4911351 DOI: 10.3389/fphys.2016.00241] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 06/03/2016] [Indexed: 12/16/2022] Open
Abstract
Aging is represented by a progressive decline in cellular functions. The age-related deformities in cardiac behaviors are the loss of cardiac myocytes through apoptosis or programmed cell death. Oxidative stress (OS) and its deleterious consequence contribute to age-related mechanical remodeling, reduced regenerative capacity, and apoptosis in cardiac tissue. The pathogenesis of OS in the elderly can predispose the heart to other cardiac complications such as atherosclerosis, hypertension, ischemic heart disease, cardiac myopathy, and so on. At the molecular level, oxidant-induced activation of Nrf2 (Nuclear erythroid-2-p45-related factor-2), a transcription factor, regulates several genes containing AREs (Antioxidant Response Element) and bring the respective translates to counteract the reactive radicals and establish homeostasis. Myriad of Nrf2 gene knockout studies in various organs such as lung, liver, kidney, brain, etc. have shown that dysregulation of Nrf2 severely affects the oxidant/ROS sensitivity and predispose the system to several pathological changes with aberrant cellular lesions. On the other hand, its gain of function chemical interventions exhibited oxidant stress resistance and cytoprotection. However, thus far, only a few investigations have shown the potential role of Nrf2 and its non-pharmacological induction in cardiac aging. Therefore, here we review the involvement of Nrf2 signaling along with its responses and ramifications on the cascade of OS under acute exercise stress (AES), moderate exercise training (MET), and endurance exercise stress (EES) conditions in the aging heart.
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Affiliation(s)
- Madhusudhanan Narasimhan
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center Lubbock, TX, USA
| | - Namakkal S Rajasekaran
- Cardiac Aging and Redox Signaling Laboratory, Center for Free Radical Biology, Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at BirminghamBirmingham, AL, USA; Division of Cardiovascular Medicine, Department of Medicine, University of Utah School of MedicineSalt Lake City, UT, USA; Department of Exercise Physiology, College of Health, University of Utah School of MedicineSalt Lake City, UT, USA
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132
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Niyazov DM, Kahler SG, Frye RE. Primary Mitochondrial Disease and Secondary Mitochondrial Dysfunction: Importance of Distinction for Diagnosis and Treatment. Mol Syndromol 2016; 7:122-37. [PMID: 27587988 DOI: 10.1159/000446586] [Citation(s) in RCA: 145] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2016] [Indexed: 12/28/2022] Open
Abstract
Mitochondrial disease refers to a heterogeneous group of disorders resulting in defective cellular energy production due to abnormal oxidative phosphorylation (oxphos). Primary mitochondrial disease (PMD) is diagnosed clinically and ideally, but not always, confirmed by a known or indisputably pathogenic mitochondrial DNA (mtDNA) or nuclear DNA (nDNA) mutation. The PMD genes either encode oxphos proteins directly or they affect oxphos function by impacting production of the complex machinery needed to run the oxphos process. However, many disorders have the 'mitochondrial' phenotype without an identifiable mtDNA or nDNA mutation or they have a variant of unknown clinical significance. Secondary mitochondrial dysfunction (SMD) can be caused by genes encoding neither function nor production of the oxphos proteins and accompanies many hereditary non-mitochondrial diseases. SMD may also be due to nongenetic causes such as environmental factors. In our practice, we see many patients with clinical signs of mitochondrial dysfunction based on phenotype, biomarkers, imaging, muscle biopsy, or negative/equivocal mtDNA or nDNA test results. In these cases, it is often tempting to assign a patient's phenotype to 'mitochondrial disease', but SMD is often challenging to distinguish from PMD. Fortunately, rapid advances in molecular testing, made possible by next generation sequencing, have been effective at least in some cases in establishing accurate diagnoses to distinguish between PMD and SMD. This is important, since their treatments and prognoses can be quite different. However, even in the absence of the ability to distinguish between PMD and SMD, treating SMD with standard treatments for PMD can be effective. We review the latest findings regarding mitochondrial disease/dysfunction and give representative examples in which differentiation between PMD and SMD has been crucial for diagnosis and treatment.
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Affiliation(s)
- Dmitriy M Niyazov
- Department of Pediatrics, Ochsner Clinic Foundation, New Orleans, La, USA
| | - Stephan G Kahler
- Department of Pediatrics, Arkansas Children's Hospital and Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, Ark., USA
| | - Richard E Frye
- Department of Pediatrics, Arkansas Children's Hospital and Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, Ark., USA
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133
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Schafer MJ, White TA, Evans G, Tonne JM, Verzosa GC, Stout MB, Mazula DL, Palmer AK, Baker DJ, Jensen MD, Torbenson MS, Miller JD, Ikeda Y, Tchkonia T, van Deursen JM, Kirkland JL, LeBrasseur NK. Exercise Prevents Diet-Induced Cellular Senescence in Adipose Tissue. Diabetes 2016; 65:1606-15. [PMID: 26983960 PMCID: PMC4878429 DOI: 10.2337/db15-0291] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 02/29/2016] [Indexed: 12/12/2022]
Abstract
Considerable evidence implicates cellular senescence in the biology of aging and chronic disease. Diet and exercise are determinants of healthy aging; however, the extent to which they affect the behavior and accretion of senescent cells within distinct tissues is not clear. Here we tested the hypothesis that exercise prevents premature senescent cell accumulation and systemic metabolic dysfunction induced by a fast-food diet (FFD). Using transgenic mice that express EGFP in response to activation of the senescence-associated p16(INK4a) promoter, we demonstrate that FFD consumption causes deleterious changes in body weight and composition as well as in measures of physical, cardiac, and metabolic health. The harmful effects of the FFD were associated with dramatic increases in several markers of senescence, including p16, EGFP, senescence-associated β-galactosidase, and the senescence-associated secretory phenotype (SASP) specifically in visceral adipose tissue. We show that exercise prevents the accumulation of senescent cells and the expression of the SASP while nullifying the damaging effects of the FFD on parameters of health. We also demonstrate that exercise initiated after long-term FFD feeding reduces senescent phenotype markers in visceral adipose tissue while attenuating physical impairments, suggesting that exercise may provide restorative benefit by mitigating accrued senescent burden. These findings highlight a novel mechanism by which exercise mediates its beneficial effects and reinforces the effect of modifiable lifestyle choices on health span.
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Affiliation(s)
- Marissa J Schafer
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN
| | - Thomas A White
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN
| | - Glenda Evans
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN
| | - Jason M Tonne
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN
| | | | - Michael B Stout
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN Department of Internal Medicine, Mayo Clinic, Rochester, MN
| | - Daniel L Mazula
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN
| | - Allyson K Palmer
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN
| | - Darren J Baker
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN
| | - Michael D Jensen
- Division of Endocrinology, Department of Medicine, Mayo Clinic, Rochester, MN
| | | | - Jordan D Miller
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN Department of Surgery, Mayo Clinic, Rochester, MN
| | - Yasuhiro Ikeda
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN
| | - Tamara Tchkonia
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN
| | - Jan M van Deursen
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - James L Kirkland
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN Department of Internal Medicine, Mayo Clinic, Rochester, MN
| | - Nathan K LeBrasseur
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN
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134
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Klenk J, Srulijes K, Schatton C, Schwickert L, Maetzler W, Becker C, Synofzik M. Ambulatory Activity Components Deteriorate Differently across Neurodegenerative Diseases: A Cross-Sectional Sensor-Based Study. NEURODEGENER DIS 2016; 16:317-23. [PMID: 27197840 DOI: 10.1159/000444802] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 02/16/2016] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND AND PURPOSE Reduced ambulatory activity is a major burden in neurodegenerative disease (NDD), leading to severe restrictions in social participation and further deterioration of motor capacities. However, objective evidence on walking behavior patterns and components underlying this impairment and its decline with disease progression is scarce for many NDDs. We aimed to unravel the detailed metrics underlying the reduced ambulatory activity in selected NDDs, and their relation to disease duration. We hypothesized that progressively reduced ambulatory activity is a feature shared across different NDDs, characterized by changes in both common and distinct components. METHODS Sixty-five subjects with NDD (n = 34 degenerative ataxia; n = 15 progressive supranuclear palsy, and n = 16 Parkinson's disease) and 38 healthy older adults (total n = 103) wore a three-axial accelerometer (activPAL3™) for 7 consecutive days. Detailed metrics of ambulatory activity were calculated. RESULTS The average daily walking duration was significantly decreased in all three NDDs, yet characterized by a differential pattern of changes in number and length of walking bouts and sit-to-stand transfers. Decline in walking duration progressed with increased disease duration in all three NDDs, yet at a differing rate. This decline was associated with progressive reductions in walking bout length and walking behavior pattern diversity in all three NDDs. CONCLUSIONS These findings provide objective evidence that reduced ambulatory activity is a shared feature across different NDDs. Moreover, they reveal that several underlying walking behavior components change with increasing disease duration, yet at a differing rate in different NDDs. This indicates that metric analysis of ambulatory activity might provide ecologically relevant and disease-specific progression and outcome markers in several NDDs.
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Affiliation(s)
- Jochen Klenk
- Department of Clinical Gerontology, Robert Bosch Hospital, Stuttgart, Germany
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135
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Carter HN, Chen CCW, Hood DA. Mitochondria, muscle health, and exercise with advancing age. Physiology (Bethesda) 2016; 30:208-23. [PMID: 25933821 DOI: 10.1152/physiol.00039.2014] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Skeletal muscle health is dependent on the optimal function of its mitochondria. With advancing age, decrements in numerous mitochondrial variables are evident in muscle. Part of this decline is due to reduced physical activity, whereas the remainder appears to be attributed to age-related alterations in mitochondrial synthesis and degradation. Exercise is an important strategy to stimulate mitochondrial adaptations in older individuals to foster improvements in muscle function and quality of life.
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Affiliation(s)
- Heather N Carter
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University, Toronto, Ontario, Canada
| | - Chris C W Chen
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University, Toronto, Ontario, Canada
| | - David A Hood
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University, Toronto, Ontario, Canada
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136
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Germain D. Sirtuins and the Estrogen Receptor as Regulators of the Mammalian Mitochondrial UPR in Cancer and Aging. Adv Cancer Res 2016; 130:211-56. [PMID: 27037754 DOI: 10.1016/bs.acr.2016.01.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
By being both the source of ATP and the mediator of apoptosis, the mitochondria are key regulators of cellular life and death. Not surprisingly alterations in the biology of the mitochondria have implications in a wide array of diseases including cancer and age-related diseases such as neurodegeneration. To protect the mitochondria against damage the mitochondrial unfolded protein response (UPR(mt)) orchestrates several pathways, including the protein quality controls, the antioxidant machinery, oxidative phosphorylation, mitophagy, and mitochondrial biogenesis. While several reports have implicated an array of transcription factors in the UPR(mt), most of the focus has been on studies of Caenorhabditis elegans, which led to the identification of ATFS-1, for which the mammalian homolog remains unknown. Meanwhile, there are studies which link the UPR(mt) to sirtuins and transcription factors of the Foxo family in both C. elegans and mammalian cells but those have been largely overlooked. This review aims at emphasizing the potential importance of these studies by building on the large body of literature supporting the key role of the sirtuins in the maintenance of the integrity of the mitochondria in both cancer and aging. Further, the estrogen receptor alpha (ERα) and beta (ERβ) are known to confer protection against mitochondrial stress, and at least ERα has been linked to the UPR(mt). Considering the difference in gender longevity, this chapter also includes a discussion of the link between the ERα and ERβ and the mitochondria in cancer and aging.
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Affiliation(s)
- D Germain
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States.
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137
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Pillai VB, Bindu S, Sharp W, Fang YH, Kim G, Gupta M, Samant S, Gupta MP. Sirt3 protects mitochondrial DNA damage and blocks the development of doxorubicin-induced cardiomyopathy in mice. Am J Physiol Heart Circ Physiol 2016; 310:H962-72. [PMID: 26873966 DOI: 10.1152/ajpheart.00832.2015] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 02/08/2016] [Indexed: 01/15/2023]
Abstract
Doxorubicin (Doxo) is a chemotherapeutic drug widely used to treat variety of cancers. One of the most serious side effects of Doxo is its dose-dependent and delayed toxicity to the heart. Doxo is known to induce cardiac mitochondrial damage. Recently, the mitochondrial sirtuin SIRT3 has been shown to protect mitochondria from oxidative stress. Here we show that overexpression of SIRT3 protects the heart from toxicity of Doxo by preventing the drug-induced mitochondrial DNA (mtDNA) damage. Doxo treatment caused depletion of Sirt3 levels both in primary cultures of cardiomyocytes and in mouse hearts, which led to massive acetylation of mitochondrial proteins. Doxo-induced toxicity to cardiomyocytes was associated with increased reactive oxygen species (ROS) production, mitochondrial fragmentation, and cell death. Overexpression of SIRT3 helped to attenuate Doxo-induced ROS levels and cardiomyocyte death. Sirt3 knockout (Sirt3.KO) mice could not endure the full dose of Doxo treatment, developed exacerbated cardiac hypertrophy, and died during the course of treatment, whereas Sirt3 transgenic (Sirt3.tg) mice were protected against Doxo-induced cardiotoxicity. Along with Sirt3, we also observed a concomitant decrease in levels of oxoguanine-DNA glycosylase-1 (OGG1), a major DNA glycosylase that hydrolyzes oxidized-guanine (8-oxo-dG) to guanine. Depletion of OGG1 levels was associated with increased mtDNA damage. Sirt3.KO mice and Doxo-treated mice showed increased 8-oxo-dG adducts in DNA and corresponding increase in mtDNA damage, whereas, 8-oxo-dG adducts and mtDNA damage were markedly reduced in Sirt3 overexpressing transgenic mice hearts. These results thus demonstrated that Sirt3 activation protects the heart from Doxo-induced cardiotoxicity by maintaining OGG1 levels and protecting mitochondria from DNA damage.
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Affiliation(s)
- Vinodkumar B Pillai
- Department of Surgery, Committee on Molecular Pathogenesis and Molecular Medicine, Biological Science Division, University of Chicago, Chicago, Illinois
| | - Samik Bindu
- Department of Surgery, Committee on Molecular Pathogenesis and Molecular Medicine, Biological Science Division, University of Chicago, Chicago, Illinois
| | - Will Sharp
- Department Medicine, Committee on Molecular Pathogenesis and Molecular Medicine, Biological Science Division, University of Chicago, Chicago, Illinois; and
| | - Yong Hu Fang
- Department Medicine, Committee on Molecular Pathogenesis and Molecular Medicine, Biological Science Division, University of Chicago, Chicago, Illinois; and
| | - Gene Kim
- Department Medicine, Committee on Molecular Pathogenesis and Molecular Medicine, Biological Science Division, University of Chicago, Chicago, Illinois; and
| | - Madhu Gupta
- Department of Physiology and Biophysics, University of Illinois, Chicago, Illinois
| | - Sadhana Samant
- Department of Surgery, Committee on Molecular Pathogenesis and Molecular Medicine, Biological Science Division, University of Chicago, Chicago, Illinois
| | - Mahesh P Gupta
- Department of Surgery, Committee on Molecular Pathogenesis and Molecular Medicine, Biological Science Division, University of Chicago, Chicago, Illinois
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138
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Safdar A, Khrapko K, Flynn JM, Saleem A, De Lisio M, Johnston APW, Kratysberg Y, Samjoo IA, Kitaoka Y, Ogborn DI, Little JP, Raha S, Parise G, Akhtar M, Hettinga BP, Rowe GC, Arany Z, Prolla TA, Tarnopolsky MA. Exercise-induced mitochondrial p53 repairs mtDNA mutations in mutator mice. Skelet Muscle 2016; 6:7. [PMID: 26834962 PMCID: PMC4733510 DOI: 10.1186/s13395-016-0075-9] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 01/05/2016] [Indexed: 11/22/2022] Open
Abstract
Background Human genetic disorders and transgenic mouse models have shown that mitochondrial DNA (mtDNA) mutations and telomere dysfunction instigate the aging process. Epidemiologically, exercise is associated with greater life expectancy and reduced risk of chronic diseases. While the beneficial effects of exercise are well established, the molecular mechanisms instigating these observations remain unclear. Results Endurance exercise reduces mtDNA mutation burden, alleviates multisystem pathology, and increases lifespan of the mutator mice, with proofreading deficient mitochondrial polymerase gamma (POLG1). We report evidence for a POLG1-independent mtDNA repair pathway mediated by exercise, a surprising notion as POLG1 is canonically considered to be the sole mtDNA repair enzyme. Here, we show that the tumor suppressor protein p53 translocates to mitochondria and facilitates mtDNA mutation repair and mitochondrial biogenesis in response to endurance exercise. Indeed, in mutator mice with muscle-specific deletion of p53, exercise failed to prevent mtDNA mutations, induce mitochondrial biogenesis, preserve mitochondrial morphology, reverse sarcopenia, or mitigate premature mortality. Conclusions Our data establish a new role for p53 in exercise-mediated maintenance of the mtDNA genome and present mitochondrially targeted p53 as a novel therapeutic modality for diseases of mitochondrial etiology. Electronic supplementary material The online version of this article (doi:10.1186/s13395-016-0075-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Adeel Safdar
- Department of Kinesiology, McMaster University, Hamilton, ON L8N 3Z5 Canada ; Department of Pediatrics, McMaster University, Hamilton, ON L8N 3Z5 Canada ; Department of Medicine, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | | | - James M Flynn
- Buck Institute for Research on Aging, Novato, CA 94945 USA
| | - Ayesha Saleem
- Department of Pediatrics, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Michael De Lisio
- Department of Kinesiology, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Adam P W Johnston
- Department of Kinesiology, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | | | - Imtiaz A Samjoo
- Department of Medical Sciences, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Yu Kitaoka
- Department of Pediatrics, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Daniel I Ogborn
- Department of Medical Sciences, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Jonathan P Little
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, BC V1V 1V7 Canada
| | - Sandeep Raha
- Department of Pediatrics, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Gianni Parise
- Department of Kinesiology, McMaster University, Hamilton, ON L8N 3Z5 Canada ; Department of Medical Physics & Applied Radiation Sciences, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Mahmood Akhtar
- Department of Medicine, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Bart P Hettinga
- Department of Pediatrics, McMaster University, Hamilton, ON L8N 3Z5 Canada
| | - Glenn C Rowe
- Division of Cardiovascular Disease, University of Alabama, Birmingham, AL 35294 USA
| | - Zoltan Arany
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Tomas A Prolla
- Departments of Genetics, University of Wisconsin, Madison, WI 53706 USA ; Departments of Medical Genetics, University of Wisconsin, Madison, WI 53706 USA
| | - Mark A Tarnopolsky
- Department of Pediatrics, McMaster University, Hamilton, ON L8N 3Z5 Canada ; Department of Medicine, McMaster University, Hamilton, ON L8N 3Z5 Canada
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139
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Garatachea N, Pareja-Galeano H, Sanchis-Gomar F, Santos-Lozano A, Fiuza-Luces C, Morán M, Emanuele E, Joyner MJ, Lucia A. Exercise attenuates the major hallmarks of aging. Rejuvenation Res 2016; 18:57-89. [PMID: 25431878 DOI: 10.1089/rej.2014.1623] [Citation(s) in RCA: 243] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Regular exercise has multi-system anti-aging effects. Here we summarize how exercise impacts the major hallmarks of aging. We propose that, besides searching for novel pharmaceutical targets of the aging process, more research efforts should be devoted to gaining insights into the molecular mediators of the benefits of exercise and to implement effective exercise interventions for elderly people.
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Affiliation(s)
- Nuria Garatachea
- 1 Faculty of Health and Sport Science, University of Zaragoza , Huesca, Spain
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140
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Cardiac Response to Oxidative Stress Induced by Mitochondrial Dysfunction. Rev Physiol Biochem Pharmacol 2016; 170:101-27. [DOI: 10.1007/112_2015_5004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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141
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Synofzik M, Maetzler W. [Successful aging: what can neurology and geriatrics contribute?]. DER NERVENARZT 2015; 86:475-80. [PMID: 25801949 DOI: 10.1007/s00115-014-4194-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The relative proportion of elderly persons in Western societies is rapidly growing, leading to an increasing frequency of age-related neurological diseases (e.g. dementia) and functional impairments (e.g. immobility). This article argues that this development should prompt a new focus in medical care. The key questions should not only be how can we improve treatment of age-related disorders but also how can we prevent age-related disorders in the first place or at least substantially delay their onset? These questions touch on an even more profound question: how can successful aging be accomplished? That is, which factors and processes characterize successful aging both on a system and on a molecular level? Thus, the crucial societal, scientific and medical challenges for Western societies are to develop and implement measures of primary prevention of dysfunctional aging. The disease-centered framework which currently determines most clinical thinking, scientific research and third party funding has to be supplemented by a novel framework of successful aging. This article defines dysfunctional aging as a convergent downstream result of multiple interacting system processes. Each of these detrimental system processes must be targeted by specific measures of geriatric primary prevention. This, in turn, implies that geriatrics does not start in the elderly or with the onset of particular geriatric disorders. Instead, it starts in the daily practice of neurology and other medical disciplines taking care of persons aged 20-40 years who are largely healthy and in the middle of their professional and personal career. Or, in a nutshell, geriatrics starts right in the middle of medical care.
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Affiliation(s)
- M Synofzik
- Abteilung für Neurodegeneration, Hertie-Institut für Klinische Hirnforschung, Zentrum für Neurologie, Universität Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Deutschland,
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142
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Exercise Modulates Oxidative Stress and Inflammation in Aging and Cardiovascular Diseases. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2016:7239639. [PMID: 26823952 PMCID: PMC4707375 DOI: 10.1155/2016/7239639] [Citation(s) in RCA: 207] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 09/28/2015] [Indexed: 12/11/2022]
Abstract
Despite the wealth of epidemiological and experimental studies indicating the protective role of regular physical activity/exercise training against the sequels of aging and cardiovascular diseases, the molecular transducers of exercise/physical activity benefits are not fully identified but should be further investigated in more integrative and innovative approaches, as they bear the potential for transformative discoveries of novel therapeutic targets. As aging and cardiovascular diseases are associated with a chronic state of oxidative stress and inflammation mediated via complex and interconnected pathways, we will focus in this review on the antioxidant and anti-inflammatory actions of exercise, mainly exerted on adipose tissue, skeletal muscles, immune system, and cardiovascular system by modulating anti-inflammatory/proinflammatory cytokines profile, redox-sensitive transcription factors such as nuclear factor kappa B, activator protein-1, and peroxisome proliferator-activated receptor gamma coactivator 1-alpha, antioxidant and prooxidant enzymes, and repair proteins such as heat shock proteins, proteasome complex, oxoguanine DNA glycosylase, uracil DNA glycosylase, and telomerase. It is important to note that the effects of exercise vary depending on the type, intensity, frequency, and duration of exercise as well as on the individual's characteristics; therefore, the development of personalized exercise programs is essential.
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143
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Joseph AM, Adhihetty PJ, Leeuwenburgh C. Beneficial effects of exercise on age-related mitochondrial dysfunction and oxidative stress in skeletal muscle. J Physiol 2015; 594:5105-23. [PMID: 26503074 DOI: 10.1113/jp270659] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 10/05/2015] [Indexed: 12/12/2022] Open
Abstract
Mitochondria are negatively affected by ageing leading to their inability to adapt to higher levels of oxidative stress and this ultimately contributes to the systemic loss of muscle mass and function termed sarcopenia. Since mitochondria are central mediators of muscle health, they have become highly sought-after targets of physiological and pharmacological interventions. Exercise is the only known strategy to combat sarcopenia and this is largely mediated through improvements in mitochondrial plasticity. More recently a critical role for mitochondrial turnover in preserving muscle has been postulated. Specifically, cellular pathways responsible for the regulation of mitochondrial turnover including biogenesis, dynamics and autophagy may become dysregulated during ageing resulting in the reduced clearance and accumulation of damaged organelles within the cell. When mitochondrial quality is compromised and homeostasis is not re-established, myonuclear cell death is activated and muscle atrophy ensues. In contrast, acute and chronic exercise attenuates these deficits, restoring mitochondrial turnover and promoting a healthier mitochondrial pool that leads to the preservation of muscle. Additionally, the magnitude of these exercise-induced mitochondrial adaptations is currently debated with several studies reporting a lower adaptability of old muscle relative to young, but the processes responsible for this diminished training response are unclear. Based on these observations, understanding the molecular details of how advancing age and exercise influence mitochondria in older muscle will provide invaluable insight into the development of exercise protocols that will maximize beneficial adaptations in the elderly. This information will also be imperative for future research exploring pharmacological targets of mitochondrial plasticity.
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Affiliation(s)
- Anna-Maria Joseph
- Department of Aging and Geriatric Research, Division of Biology of Aging, University of Florida, Gainesville, FL, 32611, USA.
| | - Peter J Adhihetty
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, 32611, USA
| | - Christiaan Leeuwenburgh
- Department of Aging and Geriatric Research, Division of Biology of Aging, University of Florida, Gainesville, FL, 32611, USA
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144
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Dai Y, Clark J, Zheng K, Kujoth GC, Prolla TA, Simon DK. Somatic mitochondrial DNA mutations do not increase neuronal vulnerability to MPTP in young POLG mutator mice. Neurotoxicol Teratol 2015; 46:62-7. [PMID: 25450660 DOI: 10.1016/j.ntt.2014.10.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 10/21/2014] [Accepted: 10/22/2014] [Indexed: 01/14/2023]
Abstract
Mitochondrial DNA (mtDNA) mutations are hypothesized to play a pathogenic role in aging and age-related neurodegenerative diseases such as Parkinson's disease (PD). In support of this, high levels of somatic mtDNA mutations in “POLG mutator” mice carrying a proofreading-deficient form of mtDNA polymerase ã (Polg(D257A)) lead to a premature aging phenotype. However, the relevance of this finding to the normal aging process has been questioned as the number of mutations is greater even in young POLG mutator mice, which shows no overt phenotype, than levels achieved during normal aging in mice. Vulnerability of dopaminergic neurons to 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) increases with age, and we hypothesized that this may result in part from the accumulation with age of somatic mtDNA mutations. If correct, then levels of mutations in young (2–3 month old) POLG mutator mice should be sufficient to increase vulnerability to MPTP. In contrast, we find that susceptibility to MPTP in both heterozygous and homozygous POLG mutator mice at this young age is not different from that of wild type littermate controls as measured by levels of tyrosine hydroxylase positive (TH+) striatal terminals, striatal dopamine and its metabolites, a marker of oxidative damage, or stereological counts of TH+ and total substantia nigra neurons. These unexpected results do not support the hypothesis that somatic mtDNA mutations contribute to the age-related vulnerability of dopaminergic neurons to MPTP. It remains possible that somatic mtDNA mutations influence vulnerability to other stressors, or require additional time for the deleterious consequences to manifest. Furthermore, the impact of the higher levels of mutations present at older ages in these mice was not assessed in our study, although a prior study also failed to detect an increase in vulnerability to MPTP in older mice. With these caveats, the current data do not provide evidence for a role of somatic mtDNA mutations in determining the vulnerability to MPTP.
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Affiliation(s)
- Ying Dai
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
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145
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Herbst EAF, Roussakis C, Matravadia S, Holloway GP. Chronic treadmill running does not enhance mitochondrial oxidative capacity in the cortex or striatum. Metabolism 2015; 64:1419-25. [PMID: 26307661 DOI: 10.1016/j.metabol.2015.07.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 06/17/2015] [Accepted: 07/02/2015] [Indexed: 10/23/2022]
Abstract
OBJECTIVE The aims of the present study were to determine in healthy animals if 1) acute exercise stimulated traditional exercise signaling pathways in the cortex and striatum, and 2) if chronic exercise training increased the oxidative capacity of these brain regions. METHODS Male C57BL/6 mice were left sedentary, acutely exercised for 15 or 60 min to examine potential signaling cascades activated by exercise, or chronically exercise for 4 wk to examine the impact of prolonged training. The cortex and striatum were analyzed for changes in the phosphorylation of AMPK, CAMKII, ERK1/2, and P38 with acute exercise, or markers of mitochondrial protein content, mtDNA copy number, and mitochondrial respiration with chronic exercise. RESULTS In mice, acute treadmill running did not alter the phosphorylation of AMPK, CAMKII, or P38 in either the cortex or the striatum, but decreased ERK1/2 phosphorylation in only the cortex for the duration of the exercise bout. Following chronic exercise training, mitochondrial respiration, mtDNA copy number, and protein content of various subunits of the electron transport chain were not altered in adult mice. CONCLUSION Combined, these data suggest that exercise does not result in increased phosphorylation of traditional signaling kinases or enhanced mitochondrial oxidative capacity in either the cortex or the striatum of healthy animals.
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Affiliation(s)
- Eric A F Herbst
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
| | - Christina Roussakis
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Sarthak Matravadia
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Graham P Holloway
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
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146
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Tischner C, Wenz T. Keep the fire burning: Current avenues in the quest of treating mitochondrial disorders. Mitochondrion 2015; 24:32-49. [DOI: 10.1016/j.mito.2015.06.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 06/18/2015] [Accepted: 06/24/2015] [Indexed: 12/18/2022]
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147
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Tarnopolsky MA, Safdar A. Dysfunctional mitochondria? Let's make more… exercise in a bottle. Mitochondrion 2015. [DOI: 10.1016/j.mito.2015.07.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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148
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Gomes M, Freitas MJ, Fardilha M. Physical Activity, Exercise, and Mammalian Testis Function: Emerging Preclinical Protein Biomarker and Integrative Biology Insights. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2015; 19:499-511. [DOI: 10.1089/omi.2015.0065] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Mariana Gomes
- Signal Transduction Laboratory, Institute for Research in Biomedicine—iBiMED, Health Sciences Program, University of Aveiro, Aveiro, Portugal
| | - Maria João Freitas
- Signal Transduction Laboratory, Institute for Research in Biomedicine—iBiMED, Health Sciences Program, University of Aveiro, Aveiro, Portugal
| | - Margarida Fardilha
- Signal Transduction Laboratory, Institute for Research in Biomedicine—iBiMED, Health Sciences Program, University of Aveiro, Aveiro, Portugal
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149
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Quarles EK, Dai DF, Tocchi A, Basisty N, Gitari L, Rabinovitch PS. Quality control systems in cardiac aging. Ageing Res Rev 2015; 23:101-15. [PMID: 25702865 PMCID: PMC4686341 DOI: 10.1016/j.arr.2015.02.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Revised: 02/02/2015] [Accepted: 02/12/2015] [Indexed: 12/31/2022]
Abstract
Cardiac aging is an intrinsic process that results in impaired cardiac function, along with cellular and molecular changes. These degenerative changes are intimately associated with quality control mechanisms. This review provides a general overview of the clinical and cellular changes which manifest in cardiac aging, and the quality control mechanisms involved in maintaining homeostasis and retarding aging. These mechanisms include autophagy, ubiquitin-mediated turnover, apoptosis, mitochondrial quality control and cardiac matrix homeostasis. Finally, we discuss aging interventions that have been observed to impact cardiac health outcomes. These include caloric restriction, rapamycin, resveratrol, GDF11, mitochondrial antioxidants and cardiolipin-targeted therapeutics. A greater understanding of the quality control mechanisms that promote cardiac homeostasis will help to understand the benefits of these interventions, and hopefully lead to further improved therapeutic modalities.
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Affiliation(s)
- Ellen K Quarles
- University of Washington School of Medicine, Department of Pathology, Box 357470, Seattle, WA 98195-7470, United States.
| | - Dao-Fu Dai
- University of Washington School of Medicine, Department of Pathology, Box 357470, Seattle, WA 98195-7470, United States.
| | - Autumn Tocchi
- University of Washington School of Medicine, Department of Pathology, Box 357470, Seattle, WA 98195-7470, United States.
| | - Nathan Basisty
- University of Washington School of Medicine, Department of Pathology, Box 357470, Seattle, WA 98195-7470, United States.
| | - Lemuel Gitari
- University of Washington School of Medicine, Department of Pathology, Box 357470, Seattle, WA 98195-7470, United States.
| | - Peter S Rabinovitch
- University of Washington School of Medicine, Department of Pathology, Box 357470, Seattle, WA 98195-7470, United States.
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150
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Crane JD, MacNeil LG, Lally JS, Ford RJ, Bujak AL, Brar IK, Kemp BE, Raha S, Steinberg GR, Tarnopolsky MA. Exercise-stimulated interleukin-15 is controlled by AMPK and regulates skin metabolism and aging. Aging Cell 2015; 14:625-34. [PMID: 25902870 PMCID: PMC4531076 DOI: 10.1111/acel.12341] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/14/2015] [Indexed: 12/28/2022] Open
Abstract
Aging is commonly associated with a structural deterioration of skin that compromises its barrier function, healing, and susceptibility to disease. Several lines of evidence show that these changes are driven largely by impaired tissue mitochondrial metabolism. While exercise is associated with numerous health benefits, there is no evidence that it affects skin tissue or that endocrine muscle-to-skin signaling occurs. We demonstrate that endurance exercise attenuates age-associated changes to skin in humans and mice and identify exercise-induced IL-15 as a novel regulator of mitochondrial function in aging skin. We show that exercise controls IL-15 expression in part through skeletal muscle AMP-activated protein kinase (AMPK), a central regulator of metabolism, and that the elimination of muscle AMPK causes a deterioration of skin structure. Finally, we establish that daily IL-15 therapy mimics some of the anti-aging effects of exercise on muscle and skin in mice. Thus, we elucidate a mechanism by which exercise confers health benefits to skin and suggest that low-dose IL-15 therapy may prove to be a beneficial strategy to attenuate skin aging.
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Affiliation(s)
- Justin D Crane
- Department of Kinesiology, McMaster UniversityHamilton, Ontario, Canada
- Department of Pediatrics, McMaster UniversityHamilton, Ontario, Canada
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster UniversityHamilton, Ontario, Canada
| | - Lauren G MacNeil
- Department of Pediatrics, McMaster UniversityHamilton, Ontario, Canada
| | - James S Lally
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster UniversityHamilton, Ontario, Canada
| | - Rebecca J Ford
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster UniversityHamilton, Ontario, Canada
| | - Adam L Bujak
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster UniversityHamilton, Ontario, Canada
| | - Ikdip K Brar
- Department of Pediatrics, McMaster UniversityHamilton, Ontario, Canada
| | - Bruce E Kemp
- Department of Medicine, St. Vincent’s Institute of Medical Research, University of MelbourneFitzroy, Vic., Australia
| | - Sandeep Raha
- Department of Pediatrics, McMaster UniversityHamilton, Ontario, Canada
| | - Gregory R Steinberg
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster UniversityHamilton, Ontario, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster UniversityHamilton, Ontario, Canada
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