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Oliván S, Calvo AC, Gasco S, Muñoz MJ, Zaragoza P, Osta R. Time-Point Dependent Activation of Autophagy and the UPS in SOD1G93A Mice Skeletal Muscle. PLoS One 2015; 10:e0134830. [PMID: 26244336 PMCID: PMC4526523 DOI: 10.1371/journal.pone.0134830] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 07/14/2015] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease characterized by a selective loss of motor neurons together with a progressive muscle weakness. Albeit the pathophysiological mechanisms of the disease remain unknown, growing evidence suggests that skeletal muscle can be a target of ALS toxicity. In particular, the two main intracellular degradation mechanisms, autophagy and the ubiquitin-proteasome degradative system (UPS) have been poorly studied in this tissue. In this study we investigated the activation of autophagy and the UPS as well as apoptosis in the skeletal muscle from SOD1G93A mice along disease progression. Our results showed a significant upregulation of proteasome activity at early symptomatic stage, while the autophagy activation was found at presymptomatic and terminal stages. The mRNA upregulated levels of LC3, p62, Beclin1, Atg5 and E2f1 were only observed at symptomatic and terminal stages, which reinforced the time-point activation of autophagy. Furthermore, no apoptosis activation was observed along disease progression. The combined data provided clear evidence for the first time that there is a time-point dependent activation of autophagy and UPS in the skeletal muscle from SOD1G93A mice.
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Affiliation(s)
- Sara Oliván
- Laboratorio de Genética y Bioquímica (LAGENBIO), Facultad de Veterinaria, Instituto Agroalimentario de Aragón (IA2), Instituto de Investigación Sanitaria Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Ana Cristina Calvo
- Laboratorio de Genética y Bioquímica (LAGENBIO), Facultad de Veterinaria, Instituto Agroalimentario de Aragón (IA2), Instituto de Investigación Sanitaria Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Samanta Gasco
- Laboratorio de Genética y Bioquímica (LAGENBIO), Facultad de Veterinaria, Instituto Agroalimentario de Aragón (IA2), Instituto de Investigación Sanitaria Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - María Jesús Muñoz
- Laboratorio de Genética y Bioquímica (LAGENBIO), Facultad de Veterinaria, Instituto Agroalimentario de Aragón (IA2), Instituto de Investigación Sanitaria Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Pilar Zaragoza
- Laboratorio de Genética y Bioquímica (LAGENBIO), Facultad de Veterinaria, Instituto Agroalimentario de Aragón (IA2), Instituto de Investigación Sanitaria Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Rosario Osta
- Laboratorio de Genética y Bioquímica (LAGENBIO), Facultad de Veterinaria, Instituto Agroalimentario de Aragón (IA2), Instituto de Investigación Sanitaria Aragón, Universidad de Zaragoza, Zaragoza, Spain
- * E-mail:
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152
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Jackson MJ. Redox regulation of muscle adaptations to contractile activity and aging. J Appl Physiol (1985) 2015; 119:163-71. [PMID: 25792715 PMCID: PMC4526708 DOI: 10.1152/japplphysiol.00760.2014] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 01/08/2015] [Indexed: 11/22/2022] Open
Abstract
Superoxide and nitric oxide are generated by skeletal muscle, and these species are increased by contractile activity. Mitochondria have long been assumed to play the primary role in generation of superoxide in muscle, but recent studies indicate that, during contractile activity, membrane-localized NADPH oxidase(s) rapidly generate(s) superoxide that plays a role in redox signaling. This process is important in upregulation of rapid and specific cytoprotective responses that aid maintenance of cell viability following contractile activity, but the overall extent to which redox signaling contributes to regulation of muscle metabolism and homeostasis following contractile activity is currently unclear, as is identification of key redox-sensitive protein targets involved in these processes. Reactive oxygen and nitrogen species have also been implicated in the loss of muscle mass and function that occurs with aging, although recent work has questioned whether oxidative damage plays a key role in these processes. A failure of redox signaling occurs in muscle during aging and may contribute to the age-related loss of muscle fibers. Whether such changes in redox signaling reflect primary age-related changes or are secondary to the fundamental mechanisms is unclear. For instance, denervated muscle fibers within muscles from aged rodents or humans appear to generate large amounts of mitochondrial hydrogen peroxide that could influence adjacent innervated fibers. Thus, in this instance, a "secondary" source of reactive oxygen species may be potentially generated as a result of a primary age-related pathology (loss of neurons), but, nevertheless, may contribute to loss of muscle mass and function during aging.
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Affiliation(s)
- Malcolm J Jackson
- MRC-Arthritis Research UK Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
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153
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Narici M, Conte M, Salvioli S, Franceschi C, Selby A, Dela F, Rieder F, Kösters A, Müller E. Alpine Skiing With total knee ArthroPlasty (ASWAP): impact on molecular and architectural features of musculo-skeletal ageing. Scand J Med Sci Sports 2015; 25 Suppl 2:33-9. [DOI: 10.1111/sms.12458] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/02/2015] [Indexed: 12/11/2022]
Affiliation(s)
- M. Narici
- MRC ARUK Centre for Musculoskeletal Ageing Research; Faculty of Medicine; University of Nottingham; Nottingham UK
| | - M. Conte
- Department of Experimental, Diagnostic and Specialty Medicine; University of Bologna; Bologna Italy
| | - S. Salvioli
- Department of Experimental, Diagnostic and Specialty Medicine; University of Bologna; Bologna Italy
| | - C. Franceschi
- Department of Experimental, Diagnostic and Specialty Medicine; University of Bologna; Bologna Italy
| | - A. Selby
- MRC ARUK Centre for Musculoskeletal Ageing Research; Faculty of Medicine; University of Nottingham; Nottingham UK
| | - F. Dela
- Department of Biomedical Sciences; Xlab - Center for Healthy Aging; University of Copenhagen; Copenhagen Denmark
| | - F. Rieder
- Department of Sport Science and Christian Doppler Laboratory “Biomechanics in Skiing”; University of Salzburg; Salzburg Austria
| | - A. Kösters
- Department of Sport Science and Christian Doppler Laboratory “Biomechanics in Skiing”; University of Salzburg; Salzburg Austria
| | - E. Müller
- Department of Sport Science and Christian Doppler Laboratory “Biomechanics in Skiing”; University of Salzburg; Salzburg Austria
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154
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Walsh ME, Bhattacharya A, Liu Y, Van Remmen H. Butyrate prevents muscle atrophy after sciatic nerve crush. Muscle Nerve 2015; 52:859-68. [PMID: 25727783 DOI: 10.1002/mus.24622] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/23/2015] [Indexed: 01/04/2023]
Abstract
INTRODUCTION Histone deacetylases (HDACs) have been implicated in neurogenic muscle atrophy, but the mechanisms by which HDAC inhibitors might have beneficial effects are not defined. METHODS We used sciatic nerve crush to determine the effect of butyrate on denervation-induced gene expression and oxidative stress. RESULTS Butyrate treatment initiated 3 weeks before injury and continued 1 week after injury increases histone acetylation and reduces muscle atrophy after nerve crush. Butyrate delivered only after nerve crush similarly prevented muscle atrophy. Butyrate had no effect on the increase in histone deacetylase 4 (HDAC4) protein levels following nerve crush but prevented the increase in expression of myogenin, MuRF1, and atrogin-1. Butyrate did not affect mitochondrial reactive oxygen species production, but it increased antioxidant enzyme activity, reduced proteasome activity, and reduced oxidative damage following nerve injury. CONCLUSIONS These data suggest that HDAC inhibitors are promising pharmacological agents for treating neurogenic muscle atrophy. Muscle Nerve 52: 859-868, 2015.
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Affiliation(s)
- Michael E Walsh
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.,Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, USA
| | - Arunabh Bhattacharya
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.,Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, USA
| | - Yuhong Liu
- Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, USA
| | - Holly Van Remmen
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, Oklahoma, 73104, USA
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155
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Grape polyphenols supplementation reduces muscle atrophy in a mouse model of chronic inflammation. Nutrition 2015; 31:1275-83. [PMID: 26333892 DOI: 10.1016/j.nut.2015.04.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 04/28/2015] [Accepted: 04/28/2015] [Indexed: 12/31/2022]
Abstract
OBJECTIVES Polyphenols (PP) have demonstrated beneficial effects on low-grade inflammation and oxidative stress; however, little is known about their effect on highly inflamed muscle. The purposes of this study were (i) to evaluate muscle alteration induced by high-grade inflammation, and (ii) to test the effects of red grape PP supplementation on these alterations. METHODS We used a transgenic mice model (transforming growth factor [TGF] mice) to develop a high T cell-dependent inflammation and C57 BL/6 control (CTL) mice model. Skeletal muscles of TGF and CTL mice were investigated for inflammation, atrophy and oxidative stress markers. Isolated mitochondria from hindlimb muscles were used for respiration with pyruvate as substrate and oxidative damages were measured by Western blot. TGF mice were supplemented with a mixture of red grape polyphenols (50 mg/kg/d) for 4 wk. Data were analyzed by one-way analysis of variance (ANOVA) and post hoc Bonferroni's multiple comparison tests. RESULTS TGF mice presented skeletal muscle inflammation, oxidative stress, mitochondrial alteration and muscle atrophy. Atrophy was associated with two distinct pathways: (i) one linked to inflammation, NF-κB activation and increased ubiquitin ligase expression, and (ii) one dependent on reactive oxygen species (ROS) production leading to damaged mitochondria accumulation and activation of caspase-9 and 3. Supplementation of TGF mice with a mixture of red grape polyphenols (50 mg/kg/d) for 4 wk improved mitochondrial function and highly decreased caspases activation, which allowed muscle atrophy mitigation. CONCLUSIONS These observations suggest that nutritional dosages of red grape polyphenols might be beneficial for reducing skeletal muscle atrophy, even in a high-grade inflammation environment.
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156
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Azpurua J, Eaton BA. Neuronal epigenetics and the aging synapse. Front Cell Neurosci 2015; 9:208. [PMID: 26074775 PMCID: PMC4444820 DOI: 10.3389/fncel.2015.00208] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/13/2015] [Indexed: 11/13/2022] Open
Abstract
Two of the most salient phenotypes of aging are cognitive decline and loss of motor function, both of which are controlled by the nervous system. Cognition and muscle contraction require that neuronal synapses develop and maintain proper structure and function. We review the literature on how normal physiological aging disrupts central and peripheral synapse function including the degradation of structure and/or control of neurotransmission. Here we also attempt to connect the work done on the epigenetics of aging to the growing literature of how epigenetic mechanisms control synapse structure and function. Lastly, we address possible roles of epigenetic mechanisms to explain why the basal rates of age-related dysfunction vary so widely across individuals.
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Affiliation(s)
- Jorge Azpurua
- Department of Physiology, University of Texas Health Science Center at San Antonio San Antonio, TX, USA
| | - Benjamin A Eaton
- Department of Physiology, University of Texas Health Science Center at San Antonio San Antonio, TX, USA
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157
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Lightfoot AP, McArdle A, Jackson MJ, Cooper RG. In the idiopathic inflammatory myopathies (IIM), do reactive oxygen species (ROS) contribute to muscle weakness? Ann Rheum Dis 2015; 74:1340-6. [DOI: 10.1136/annrheumdis-2014-207172] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 04/05/2015] [Indexed: 12/13/2022]
Abstract
The idiopathic inflammatory myopathies (IIMs) are a group of rare autoimmune disorders, collectively known as myositis. Affected patients present with proximal muscle weakness, which usually improves following treatment with immunosuppressants, but often incompletely so, thus many patients remain weak. IIMs are characterised histologically by inflammatory cell infiltrates into skeletal muscle and overexpression of major histocompatibility complex I on muscle cell surfaces. Although inflammatory cell infiltrates represent a major feature of myositis there is growing evidence that muscle weakness correlates only poorly with the degree of cellular infiltration, while weakness may in fact precede such infiltrations. The mechanisms underpinning such non-immune cell mediated weakness in IIM are poorly understood. Activation of the endoplasmic reticulum stress pathways appears to be a potential contributor. Data from non-muscle cells indicate that endoplasmic reticulum stress results in altered redox homeostasis capable of causing oxidative damage. In myopathological situations other than IIM, as seen in ageing and sepsis, evidence supports an important role for reactive oxygen species (ROS). Modified ROS generation is associated with mitochondrial dysfunction, depressed force generation and activation of muscle catabolic and autophagy pathways. Despite the growing evidence demonstrating a key role for ROS in skeletal muscle dysfunction in myopathologies other than IIM, no research has yet investigated the role of modified generation of ROS in inducing the weakness characteristic of IIM. This article reviews current knowledge regarding muscle weakness in the absence of immune cells in IIM, and provides a background to the potential role of modified ROS generation as a mechanism of muscle dysfunction. The authors suggest that ROS-mediated mechanisms are potentially involved in non-immune cell mediated weakness seen in IIM and outline how these mechanisms might be investigated in this context. This appears a timely strategy, given recent developments in targeted therapies which specifically modify ROS generation.
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158
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Sataranatarajan K, Qaisar R, Davis C, Sakellariou GK, Vasilaki A, Zhang Y, Liu Y, Bhaskaran S, McArdle A, Jackson M, Brooks SV, Richardson A, Van Remmen H. Neuron specific reduction in CuZnSOD is not sufficient to initiate a full sarcopenia phenotype. Redox Biol 2015; 5:140-148. [PMID: 25917273 PMCID: PMC5022075 DOI: 10.1016/j.redox.2015.04.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 04/08/2015] [Accepted: 04/13/2015] [Indexed: 11/27/2022] Open
Abstract
Our previous studies showed that adult (8 month) mice lacking CuZn-superoxide dismutase (CuZnSOD, Sod1KO mice) have neuromuscular changes resulting in dramatic accelerated muscle atrophy and weakness that mimics age-related sarcopenia. We have further shown that loss of CuZnSOD targeted to skeletal muscle alone results in only mild weakness and no muscle atrophy. In this study, we targeted deletion of CuZnSOD specifically to neurons (nSod1KO mice) and determined the effect on muscle mass and weakness. The nSod1KO mice show a significant loss of CuZnSOD activity and protein level in brain and spinal cord but not in muscle tissue. The masses of the gastrocnemius, tibialis anterior and extensor digitorum longus (EDL) muscles were not reduced in nSod1KO compared to wild type mice, even at 20 months of age, although the quadriceps and soleus muscles showed small but statistically significant reductions in mass in the nSod1KO mice. Maximum isometric specific force was reduced by 8–10% in the gastrocnemius and EDL muscle of nSod1KO mice, while soleus was not affected. Muscle mitochondrial ROS generation and oxidative stress measured by levels of reactive oxygen/nitrogen species (RONS) regulatory enzymes, protein nitration and F2-isoprostane levels were not increased in muscle from the nSod1KO mice. Although we did not find evidence of denervation in the nSod1KO mice, neuromuscular junction morphology was altered and the expression of genes associated with denervation acetylcholine receptor subunit alpha (AChRα), the transcription factor, Runx1 and GADD45α) was increased, supporting a role for neuronal loss of CuZnSOD initiating alterations at the neuromuscular junction. These results and our previous studies support the concept that CuZnSOD deficits in either the motor neuron or muscle alone are not sufficient to initiate a full sarcopenic phenotype and that deficits in both tissues are required to recapitulate the loss of muscle observed in Sod1KO mice. CuZnSOD deletion in nSod1KO mice does not induce an overt sarcopenia phenotype. Force is slightly reduced in the gastrocnemius of nSod1KO mice but mass is unaffected. Neuronal Sod1 depletion does not induce denervation despite altered NMJ morphology. Neuronal Sod1 depletion does not induce muscle oxidative stress or mitochondrial ROS. Deficits in both motor neurons and muscle are required to initiate sarcopenia.
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Affiliation(s)
| | - Rizwan Qaisar
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Carol Davis
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Giorgos K Sakellariou
- MRC Arthritis Research UK Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK
| | - Aphrodite Vasilaki
- MRC Arthritis Research UK Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK
| | - Yiqiang Zhang
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Yuhong Liu
- Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Shylesh Bhaskaran
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Anne McArdle
- MRC Arthritis Research UK Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK
| | - Malcolm Jackson
- MRC Arthritis Research UK Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK
| | - Susan V Brooks
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Arlan Richardson
- Oklahoma VA Medical Center, Oklahoma City, OK 73104, USA; Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center and Oklahoma City VA Medical Center, Oklahoma City, OK, USA
| | - Holly Van Remmen
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Oklahoma VA Medical Center, Oklahoma City, OK 73104, USA.
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159
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Huang TT, Leu D, Zou Y. Oxidative stress and redox regulation on hippocampal-dependent cognitive functions. Arch Biochem Biophys 2015; 576:2-7. [PMID: 25797440 DOI: 10.1016/j.abb.2015.03.014] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 03/12/2015] [Accepted: 03/13/2015] [Indexed: 12/17/2022]
Abstract
Hippocampal-dependent cognitive functions rely on production of new neurons and maintenance of dendritic structures to provide the synaptic plasticity needed for learning and formation of new memories. Hippocampal formation is exquisitely sensitive to patho-physiological changes, and reduced antioxidant capacity and exposure to low dose irradiation can significantly impede hippocampal-dependent functions of learning and memory by reducing the production of new neurons and alter dendritic structures in the hippocampus. Although the mechanism leading to impaired cognitive functions is complex, persistent oxidative stress likely plays an important role in the SOD-deficient and radiation-exposed hippocampal environment. Aging is associated with increased production of pro-oxidants and accumulation of oxidative end products. Similar to the hippocampal defects observed in SOD-deficient mice and mice exposed to low dose irradiation, reduced capacity in learning and memory, diminishing hippocampal neurogenesis, and altered dendritic network are universal in the aging brains. Given the similarities in cellular and structural changes in the aged, SOD-deficient, and radiation-exposed hippocampal environment and the corresponding changes in cognitive decline, understanding the shared underlying mechanism will provide more flexible and efficient use of SOD deficiency or irradiation to model age-related changes in cognitive functions and identify potential therapeutic or intervention methods.
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Affiliation(s)
- Ting-Ting Huang
- Geriatric Research, Education, and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA, USA; Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA.
| | - David Leu
- Geriatric Research, Education, and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA, USA; Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Yani Zou
- Geriatric Research, Education, and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA, USA; Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
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160
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Jeon S, Hur J, Kim J. DHEA Alleviates Oxidative Stress of Muscle Cells via Activation of Nrf2 Pathway. Appl Biochem Biotechnol 2015; 176:22-32. [DOI: 10.1007/s12010-015-1500-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 01/19/2015] [Indexed: 11/24/2022]
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161
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Muscle-derived extracellular signal-regulated kinases 1 and 2 are required for the maintenance of adult myofibers and their neuromuscular junctions. Mol Cell Biol 2015; 35:1238-53. [PMID: 25605336 DOI: 10.1128/mcb.01071-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The Ras-extracellular signal-regulated kinase 1 and 2 (ERK1/2) pathway appears to be important for the development, maintenance, aging, and pathology of mammalian skeletal muscle. Yet no gene targeting of Erk1/2 in muscle fibers in vivo has been reported to date. We combined a germ line Erk1 mutation with Cre-loxP Erk2 inactivation in skeletal muscle to produce, for the first time, mice lacking ERK1/2 selectively in skeletal myofibers. Animals lacking muscle ERK1/2 displayed stunted postnatal growth, muscle weakness, and a shorter life span. Their muscles examined in this study, sternomastoid and tibialis anterior, displayed fragmented neuromuscular synapses and a mixture of modest fiber atrophy and loss but failed to show major changes in fiber type composition or absence of cell surface dystrophin. Whereas the lack of only ERK1 had no effects on the phenotypes studied, the lack of myofiber ERK2 explained synaptic fragmentation in the sternomastoid but not the tibialis anterior and a decrease in the expression of the acetylcholine receptor (AChR) epsilon subunit gene mRNA in both muscles. A reduction in AChR protein was documented in line with the above mRNA results. Evidence of partial denervation was found in the sternomastoid but not the tibialis anterior. Thus, myofiber ERK1/2 are differentially required for the maintenance of myofibers and neuromuscular synapses in adult mice.
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162
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Zhang Y, Fischer KE, Soto V, Liu Y, Sosnowska D, Richardson A, Salmon AB. Obesity-induced oxidative stress, accelerated functional decline with age and increased mortality in mice. Arch Biochem Biophys 2015; 576:39-48. [PMID: 25558793 DOI: 10.1016/j.abb.2014.12.018] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 12/05/2014] [Accepted: 12/20/2014] [Indexed: 12/22/2022]
Abstract
Obesity is a serious chronic disease that increases the risk of numerous co-morbidities including metabolic syndrome, cardiovascular disease and cancer as well as increases risk of mortality, leading some to suggest this condition represents accelerated aging. Obesity is associated with significant increases in oxidative stress in vivo and, despite the well-explored relationship between oxidative stress and aging, the role this plays in the increased mortality of obese subjects remains an unanswered question. Here, we addressed this by undertaking a comprehensive, longitudinal study of a group of high fat-fed obese mice and assessed both their changes in oxidative stress and in their performance in physiological assays known to decline with aging. In female C57BL/6J mice fed a high-fat diet starting in adulthood, mortality was significantly increased as was oxidative damage in vivo. High fat-feeding significantly accelerated the decline in performance in several assays, including activity, gait, and rotarod. However, we also found that obesity had little effect on other markers of function and actually improved performance in grip strength, a marker of muscular function. Together, this first comprehensive assessment of longitudinal, functional changes in high fat-fed mice suggests that obesity may induce segmental acceleration of some of the aging process.
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Affiliation(s)
- Yiqiang Zhang
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA; Department of Physiology, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Kathleen E Fischer
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Vanessa Soto
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Yuhong Liu
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Danuta Sosnowska
- Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center and Oklahoma City VA Medical Center, Oklahoma, OK, USA
| | - Arlan Richardson
- Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center and Oklahoma City VA Medical Center, Oklahoma, OK, USA
| | - Adam B Salmon
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA; Department of Molecular Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA; Geriatric Research, Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, TX, USA.
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163
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Watanabe K, Shibuya S, Ozawa Y, Nojiri H, Izuo N, Yokote K, Shimizu T. Superoxide dismutase 1 loss disturbs intracellular redox signaling, resulting in global age-related pathological changes. BIOMED RESEARCH INTERNATIONAL 2014; 2014:140165. [PMID: 25276767 PMCID: PMC4170698 DOI: 10.1155/2014/140165] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 07/29/2014] [Accepted: 08/06/2014] [Indexed: 01/14/2023]
Abstract
Aging is characterized by increased oxidative stress, chronic inflammation, and organ dysfunction, which occur in a progressive and irreversible manner. Superoxide dismutase (SOD) serves as a major antioxidant and neutralizes superoxide radicals throughout the body. In vivo studies have demonstrated that copper/zinc superoxide dismutase-deficient (Sod1(-/-)) mice show various aging-like pathologies, accompanied by augmentation of oxidative damage in organs. We found that antioxidant treatment significantly attenuated the age-related tissue changes and oxidative damage-associated p53 upregulation in Sod1(-/-) mice. This review will focus on various age-related pathologies caused by the loss of Sod1 and will discuss the molecular mechanisms underlying the pathogenesis in Sod1(-/-) mice.
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Affiliation(s)
- Kenji Watanabe
- Department of Advanced Aging Medicine, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan
- Department of Clinical Cell Biology and Medicine, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan
| | - Shuichi Shibuya
- Department of Advanced Aging Medicine, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan
| | - Yusuke Ozawa
- Department of Advanced Aging Medicine, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan
| | - Hidetoshi Nojiri
- Department of Orthopaedics, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Naotaka Izuo
- Department of Advanced Aging Medicine, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan
| | - Koutaro Yokote
- Department of Clinical Cell Biology and Medicine, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan
| | - Takahiko Shimizu
- Department of Advanced Aging Medicine, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan
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164
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Carnio S, LoVerso F, Baraibar MA, Longa E, Khan MM, Maffei M, Reischl M, Canepari M, Loefler S, Kern H, Blaauw B, Friguet B, Bottinelli R, Rudolf R, Sandri M. Autophagy impairment in muscle induces neuromuscular junction degeneration and precocious aging. Cell Rep 2014; 8:1509-21. [PMID: 25176656 PMCID: PMC4534571 DOI: 10.1016/j.celrep.2014.07.061] [Citation(s) in RCA: 289] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 02/04/2014] [Accepted: 07/31/2014] [Indexed: 11/19/2022] Open
Abstract
The cellular basis of age-related tissue deterioration remains largely obscure. The ability to activate compensatory mechanisms in response to environmental stress is an important factor for survival and maintenance of cellular functions. Autophagy is activated both under short and prolonged stress and is required to clear the cell of dysfunctional organelles and altered proteins. We report that specific autophagy inhibition in muscle has a major impact on neuromuscular synaptic function and, consequently, on muscle strength, ultimately affecting the lifespan of animals. Inhibition of autophagy also exacerbates aging phenotypes in muscle, such as mitochondrial dysfunction, oxidative stress, and profound weakness. Mitochondrial dysfunction and oxidative stress directly affect acto-myosin interaction and force generation but show a limited effect on stability of neuromuscular synapses. These results demonstrate that age-related deterioration of synaptic structure and function is exacerbated by defective autophagy. Autophagy in muscle decreases with age, and rescue prevents muscle loss Autophagy inhibition in muscles shortens animal lifespan Autophagy is required to maintain a normal muscle-nerve interaction Autophagy impairment induces oxidation of contractile proteins, causing weakness
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Affiliation(s)
- Silvia Carnio
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, 35129 Padova, Italy
| | - Francesca LoVerso
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, 35129 Padova, Italy
| | - Martin Andres Baraibar
- Laboratoire de Biologie Cellulaire du Vieillissement, UR4, Université Pierre et Marie Curie-Paris 6, 75252 Paris Cedex 05, France
| | - Emanuela Longa
- Department of Molecular Medicine and Interuniversity Institute of Myology, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Muzamil Majid Khan
- Institut für Angewandte Informatik, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
| | - Manuela Maffei
- Department of Molecular Medicine and Interuniversity Institute of Myology, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Markus Reischl
- Institut für Angewandte Informatik, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
| | - Monica Canepari
- Department of Molecular Medicine and Interuniversity Institute of Myology, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Stefan Loefler
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, 1171 Vienna, Austria
| | - Helmut Kern
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, 1171 Vienna, Austria
| | - Bert Blaauw
- Department of Biomedical Sciences, University of Padova, 35121 Padova, Italy
| | - Bertrand Friguet
- Laboratoire de Biologie Cellulaire du Vieillissement, UR4, Université Pierre et Marie Curie-Paris 6, 75252 Paris Cedex 05, France
| | - Roberto Bottinelli
- Department of Molecular Medicine and Interuniversity Institute of Myology, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy; Fondazione Salvatore Maugeri (IRCCS), Scientific Institute of Pavia, 27100 Pavia, Italy
| | - Rüdiger Rudolf
- Institut für Angewandte Informatik, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany; Institut für Toxikologie und Genetik, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany; Institut für Molekular und Zellbiologie, University of Applied Sciences Mannheim, 68163 Mannheim, Germany; Institut für Medizintechnologie, University of Applied Sciences Mannheim and University of Heidelberg, 68163 Mannheim, Germany
| | - Marco Sandri
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, 35129 Padova, Italy; Department of Biomedical Sciences, University of Padova, 35121 Padova, Italy; Institute of Neuroscience, Consiglio Nazionale delle Ricerche, 35121 Padova, Italy; Department of Medicine, McGill University, Montreal QC H3A 0G4, Canada; Telethon Institute of Genetics and Medicine (TIGEM), 80131 Napoli, Italy.
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165
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A systematic review of the evidence that brain structure is related to muscle structure and their relationship to brain and muscle function in humans over the lifecourse. BMC Geriatr 2014; 14:85. [PMID: 25011478 PMCID: PMC4105796 DOI: 10.1186/1471-2318-14-85] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 07/01/2014] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND An association between cognition and physical function has been shown to exist but the roles of muscle and brain structure in this relationship are not fully understood. A greater understanding of these relationships may lead to identification of the underlying mechanisms in this important area of research. This systematic review examines the evidence for whether: a) brain structure is related to muscle structure; b) brain structure is related to muscle function; and c) brain function is related to muscle structure in healthy children and adults. METHODS Medline, Embase, CINAHL and PsycINFO were searched on March 6th 2014. A grey literature search was performed using Google and Google Scholar. Hand searching through citations and references of relevant articles was also undertaken. RESULTS 53 articles were included in the review; mean age of the subjects ranged from 8.8 to 85.5 years old. There is evidence of a positive association between both whole brain volume and white matter (WM) volume and muscle size. Total grey matter (GM) volume was not associated with muscle size but some areas of regional GM volume were associated with muscle size (right temporal pole and bilateral ventromedial prefrontal cortex). No evidence was found of a relationship between grip strength and whole brain volume however there was some evidence of a positive association with WM volume. Conversely, there is evidence that gait speed is positively associated with whole brain volume; this relationship may be driven by total WM volume or regional GM volumes, specifically the hippocampus. Markers of brain ageing, that is brain atrophy and greater accumulation of white matter hyperintensities (WMH), were associated with grip strength and gait speed. The location of WMH is important for gait speed; periventricular hyperintensities and brainstem WMH are associated with gait speed but subcortical WMH play less of a role. Cognitive function does not appear to be associated with muscle size. CONCLUSION There is evidence that brain structure is associated with muscle structure and function. Future studies need to follow these interactions longitudinally to understand potential causal relationships.
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166
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Shi Y, Ivannikov MV, Walsh ME, Liu Y, Zhang Y, Jaramillo CA, Macleod GT, Van Remmen H. The lack of CuZnSOD leads to impaired neurotransmitter release, neuromuscular junction destabilization and reduced muscle strength in mice. PLoS One 2014; 9:e100834. [PMID: 24971750 PMCID: PMC4074103 DOI: 10.1371/journal.pone.0100834] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 05/29/2014] [Indexed: 11/29/2022] Open
Abstract
Elevated reactive oxygen species (ROS) production and ROS-dependent protein damage is a common observation in the pathogenesis of many muscle wasting disorders, including sarcopenia. However, the contribution of elevated ROS levels to –a breakdown in neuromuscular communication and muscle atrophy remains unknown. In this study, we examined a copper zinc superoxide dismutase [CuZnSOD (Sod1)] knockout mouse (Sod1−/−), a mouse model of elevated oxidative stress that exhibits accelerated loss of muscle mass, which recapitulates many phenotypes of sarcopenia as early as 5 months of age. We found that young adult Sod1−/− mice display a considerable reduction in hind limb skeletal muscle mass and strength when compared to age-matched wild-type mice. These changes are accompanied by gross alterations in neuromuscular junction (NMJ) morphology, including reduced occupancy of the motor endplates by axons, terminal sprouting and axon thinning and irregular swelling. Surprisingly however, the average density of acetylcholine receptors in endplates is preserved. Using in vivo electromyography and ex vivo electrophysiological studies of hind limb muscles in Sod1−/− mice, we found that motor axons innervating the extensor digitorum longus (EDL) and gastrocnemius muscles release fewer synaptic vesicles upon nerve stimulation. Recordings from individually identified EDL NMJs show that reductions in neurotransmitter release are apparent in the Sod1−/− mice even when endplates are close to fully innervated. However, electrophysiological properties, such as input resistance, resting membrane potential and spontaneous neurotransmitter release kinetics (but not frequency) are similar between EDL muscles of Sod1−/− and wild-type mice. Administration of the potassium channel blocker 3,4-diaminopyridine, which broadens the presynaptic action potential, improves both neurotransmitter release and muscle strength. Together, these results suggest that ROS-associated motor nerve terminal dysfunction is a contributor to the observed muscle changes in Sod1−/− mice.
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Affiliation(s)
- Yun Shi
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, United States of America
| | - Maxim V. Ivannikov
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Michael E. Walsh
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Yuhong Liu
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, United States of America
| | - Yiqiang Zhang
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Carlos A. Jaramillo
- Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, United States of America
- Department of Rehabilitation Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Gregory T. Macleod
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Holly Van Remmen
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Oklahoma City VA Medical Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
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167
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Haptoglobin is required to prevent oxidative stress and muscle atrophy. PLoS One 2014; 9:e100745. [PMID: 24959824 PMCID: PMC4069100 DOI: 10.1371/journal.pone.0100745] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 05/29/2014] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Oxidative stress (OS) plays a major role on tissue function. Several catabolic or stress conditions exacerbate OS, inducing organ deterioration. Haptoglobin (Hp) is a circulating acute phase protein, produced by liver and adipose tissue, and has an important anti-oxidant function. Hp is induced in pro-oxidative conditions such as systemic inflammation or obesity. The role of systemic factors that modulate oxidative stress inside muscle cells is still poorly investigated. RESULTS We used Hp knockout mice (Hp-/-) to determine the role of this protein and therefore, of systemic OS in maintenance of muscle mass and function. Absence of Hp caused muscle atrophy and weakness due to activation of an atrophy program. When animals were stressed by acute exercise or by high fat diet (HFD), OS, muscle atrophy and force drop were exacerbated in Hp-/-. Depending from the stress condition, autophagy-lysosome and ubiquitin-proteasome systems were differently induced. CONCLUSIONS Hp is required to prevent OS and the activation of pathways leading to muscle atrophy and weakness in normal condition and upon metabolic challenges.
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168
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Edrey YH, Salmon AB. Revisiting an age-old question regarding oxidative stress. Free Radic Biol Med 2014; 71:368-378. [PMID: 24704971 PMCID: PMC4049226 DOI: 10.1016/j.freeradbiomed.2014.03.038] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 03/27/2014] [Accepted: 03/27/2014] [Indexed: 02/06/2023]
Abstract
Significant advances in maintaining health throughout life can be made through a clear understanding of the fundamental mechanisms that regulate aging. The Oxidative Stress Theory of Aging (OSTA) is probably the most well studied mechanistic theory of aging and suggests that the rate of aging is controlled by accumulation of oxidative damage. To directly test the OSTA, aging has been measured in several lines of mice with genetic alterations in the expression of enzymatic antioxidants. Under its strictest interpretation, these studies do not support the OSTA, as modulation of antioxidant expression does not generally affect mouse life span. However, the incidence of many age-related diseases and pathologies is altered in these models, suggesting that oxidative stress does significantly influence some aspects of the aging process. Further, oxidative stress may affect aging in disparate patterns among tissues or under various environmental conditions. In this review, we summarize the current literature regarding aging in antioxidant mutant mice and offer several interpretations of their support of the OSTA.
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Affiliation(s)
- Yael H Edrey
- The Sam and Ann Barshop Institute for Longevity and Aging Studies and San Antonio, TX 78229, USA
| | - Adam B Salmon
- The Sam and Ann Barshop Institute for Longevity and Aging Studies and San Antonio, TX 78229, USA; The Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, TX 78229, USA; Department of Molecular Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA.
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169
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Dai DF, Chiao YA, Marcinek DJ, Szeto HH, Rabinovitch PS. Mitochondrial oxidative stress in aging and healthspan. LONGEVITY & HEALTHSPAN 2014; 3:6. [PMID: 24860647 DOI: 10.1201/b21905] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 03/10/2014] [Indexed: 05/26/2023]
Abstract
The free radical theory of aging proposes that reactive oxygen species (ROS)-induced accumulation of damage to cellular macromolecules is a primary driving force of aging and a major determinant of lifespan. Although this theory is one of the most popular explanations for the cause of aging, several experimental rodent models of antioxidant manipulation have failed to affect lifespan. Moreover, antioxidant supplementation clinical trials have been largely disappointing. The mitochondrial theory of aging specifies more particularly that mitochondria are both the primary sources of ROS and the primary targets of ROS damage. In addition to effects on lifespan and aging, mitochondrial ROS have been shown to play a central role in healthspan of many vital organ systems. In this article we review the evidence supporting the role of mitochondrial oxidative stress, mitochondrial damage and dysfunction in aging and healthspan, including cardiac aging, age-dependent cardiovascular diseases, skeletal muscle aging, neurodegenerative diseases, insulin resistance and diabetes as well as age-related cancers. The crosstalk of mitochondrial ROS, redox, and other cellular signaling is briefly presented. Potential therapeutic strategies to improve mitochondrial function in aging and healthspan are reviewed, with a focus on mitochondrial protective drugs, such as the mitochondrial antioxidants MitoQ, SkQ1, and the mitochondrial protective peptide SS-31.
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Affiliation(s)
- Dao-Fu Dai
- Department of Pathology, University of Washington, 1959 Pacific Ave NE, HSB-K081, Seattle, WA 98195, USA
| | - Ying Ann Chiao
- Department of Pathology, University of Washington, 1959 Pacific Ave NE, HSB-K081, Seattle, WA 98195, USA
| | - David J Marcinek
- Department of Radiology, University of Washington, Seattle, WA, USA
| | - Hazel H Szeto
- Department of Pharmacology, Weill Cornell Medical College, New York, NY, USA
| | - Peter S Rabinovitch
- Department of Pathology, University of Washington, 1959 Pacific Ave NE, HSB-K081, Seattle, WA 98195, USA
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170
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Mitochondrial oxidative stress in aging and healthspan. LONGEVITY & HEALTHSPAN 2014; 3:6. [PMID: 24860647 PMCID: PMC4013820 DOI: 10.1186/2046-2395-3-6] [Citation(s) in RCA: 301] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 03/10/2014] [Indexed: 02/07/2023]
Abstract
The free radical theory of aging proposes that reactive oxygen species (ROS)-induced accumulation of damage to cellular macromolecules is a primary driving force of aging and a major determinant of lifespan. Although this theory is one of the most popular explanations for the cause of aging, several experimental rodent models of antioxidant manipulation have failed to affect lifespan. Moreover, antioxidant supplementation clinical trials have been largely disappointing. The mitochondrial theory of aging specifies more particularly that mitochondria are both the primary sources of ROS and the primary targets of ROS damage. In addition to effects on lifespan and aging, mitochondrial ROS have been shown to play a central role in healthspan of many vital organ systems. In this article we review the evidence supporting the role of mitochondrial oxidative stress, mitochondrial damage and dysfunction in aging and healthspan, including cardiac aging, age-dependent cardiovascular diseases, skeletal muscle aging, neurodegenerative diseases, insulin resistance and diabetes as well as age-related cancers. The crosstalk of mitochondrial ROS, redox, and other cellular signaling is briefly presented. Potential therapeutic strategies to improve mitochondrial function in aging and healthspan are reviewed, with a focus on mitochondrial protective drugs, such as the mitochondrial antioxidants MitoQ, SkQ1, and the mitochondrial protective peptide SS-31.
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171
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Sheng Y, Abreu IA, Cabelli DE, Maroney MJ, Miller AF, Teixeira M, Valentine JS. Superoxide dismutases and superoxide reductases. Chem Rev 2014; 114:3854-918. [PMID: 24684599 PMCID: PMC4317059 DOI: 10.1021/cr4005296] [Citation(s) in RCA: 605] [Impact Index Per Article: 60.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Yuewei Sheng
- Department
of Chemistry and Biochemistry, University
of California Los Angeles, Los
Angeles, California 90095, United States
| | - Isabel A. Abreu
- Instituto
de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
- Instituto
de Biologia Experimental e Tecnológica, Av. da República,
Qta. do Marquês, Estação Agronómica Nacional,
Edificio IBET/ITQB, 2780-157, Oeiras, Portugal
| | - Diane E. Cabelli
- Chemistry
Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Michael J. Maroney
- Department
of Chemistry, University of Massachusetts
Amherst, Amherst, Massachusetts 01003, United States
| | - Anne-Frances Miller
- Department
of Chemistry, University of Kentucky, Lexington, Kentucky 40506-0055, United States
| | - Miguel Teixeira
- Instituto
de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
| | - Joan Selverstone Valentine
- Department
of Chemistry and Biochemistry, University
of California Los Angeles, Los
Angeles, California 90095, United States
- Department
of Bioinspired Sciences, Ewha Womans University, Seoul 120-750, Republic of Korea
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172
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Basualto-Alarcón C, Varela D, Duran J, Maass R, Estrada M. Sarcopenia and Androgens: A Link between Pathology and Treatment. Front Endocrinol (Lausanne) 2014; 5:217. [PMID: 25566189 PMCID: PMC4270249 DOI: 10.3389/fendo.2014.00217] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 12/01/2014] [Indexed: 12/25/2022] Open
Abstract
Sarcopenia, the age-related loss of skeletal muscle mass and function, is becoming more prevalent as the lifespan continues to increase in most populations. As sarcopenia is highly disabling, being associated with increased risk of dependence, falls, fractures, weakness, disability, and death, development of approaches to its prevention and treatment are required. Androgens are the main physiologic anabolic steroid hormones and normal testosterone levels are necessary for a range of developmental and biological processes, including maintenance of muscle mass. Testosterone concentrations decline as age increase, suggesting that low plasma testosterone levels can cause or accelerate muscle- and age-related diseases, as sarcopenia. Currently, there is increasing interest on the anabolic properties of testosterone for therapeutic use in muscle diseases including sarcopenia. However, the pathophysiological mechanisms underlying this muscle syndrome and its relationship with plasma level of androgens are not completely understood. This review discusses the recent findings regarding sarcopenia, the intrinsic, and extrinsic mechanisms involved in the onset and progression of this disease and the treatment approaches that have been developed based on testosterone deficiency and their implications.
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Affiliation(s)
- Carla Basualto-Alarcón
- Programa de Anatomía y Biología del Desarrollo, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - Diego Varela
- Programa de Fisiología y Biofísica, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - Javier Duran
- Programa de Fisiología y Biofísica, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - Rodrigo Maass
- Facultad de Medicina, Departamento de Morfofunción, Universidad Diego Portales, Santiago, Chile
| | - Manuel Estrada
- Programa de Fisiología y Biofísica, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
- *Correspondence: Manuel Estrada, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Independencia 1027, Santiago 8389100, Chile e-mail:
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173
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Sakellariou GK, Davis CS, Shi Y, Ivannikov MV, Zhang Y, Vasilaki A, Macleod GT, Richardson A, Van Remmen H, Jackson MJ, McArdle A, Brooks SV. Neuron-specific expression of CuZnSOD prevents the loss of muscle mass and function that occurs in homozygous CuZnSOD-knockout mice. FASEB J 2013; 28:1666-81. [PMID: 24378874 DOI: 10.1096/fj.13-240390] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Deletion of copper-zinc superoxide dismutase (CuZnSOD) in Sod1(-/-) mice leads to accelerated loss of muscle mass and force during aging, but the losses do not occur with muscle-specific deletion of CuZnSOD. To determine the role of motor neurons in the muscle decline, we generated transgenic Sod1(-/-) mice in which CuZnSOD was expressed under control of the synapsin 1 promoter (SynTgSod1(-/-) mice). SynTgSod1(-/-) mice expressed CuZnSOD in brain, spinal cord, and peripheral nerve, but not in other tissues. Sciatic nerve CuZnSOD content in SynTgSod1(-/-) mice was ~20% that of control mice, but no reduction in muscle mass or isometric force was observed in SynTgSod1(-/-) mice compared with control animals, whereas muscles of age-matched Sod1(-/-) mice displayed 30-40% reductions in mass and force. In addition, increased oxidative damage and adaptations in stress responses observed in muscles of Sod1(-/-) mice were absent in SynTgSod1(-/-) mice, and degeneration of neuromuscular junction (NMJ) structure and function occurred in Sod1(-/-) mice but not in SynTgSod1(-/-) mice. Our data demonstrate that specific CuZnSOD expression in neurons is sufficient to preserve NMJ and skeletal muscle structure and function in Sod1(-/-) mice and suggest that redox homeostasis in motor neurons plays a key role in initiating sarcopenia during aging.
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Affiliation(s)
- Giorgos K Sakellariou
- 1University of Michigan, 2029 Biomedical Sciences Research Bldg., 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200, USA.
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174
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Tohma H, El-Shafey AF, Croft K, Shavlakadze T, Grounds MD, Arthur PG. Protein thiol oxidation does not change in skeletal muscles of aging female mice. Biogerontology 2013; 15:87-98. [PMID: 24311290 DOI: 10.1007/s10522-013-9483-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 11/25/2013] [Indexed: 12/25/2022]
Abstract
Oxidative stress caused by reactive oxygen species is proposed to cause age related muscle wasting (sarcopenia). Reversible oxidation of protein thiols by reactive oxygen species can affect protein function, so we evaluated whether muscle wasting in normal aging was associated with a pervasive increase in reversible oxidation of protein thiols or with an increase in irreversible oxidative damage to macromolecules. In gastrocnemius muscles of C57BL/6J female mice aged 3, 15, 24, 27, and 29 months there was no age related increase in protein thiol oxidation. In contrast, there was a significant correlation (R (2) = 0.698) between increasing protein carbonylation, a measure of irreversible oxidative damage to proteins, and loss of mass of gastrocnemius muscles in aging female mice. In addition, there was an age-related increase in lipofuscin content, an aggregate of oxidised proteins and lipids, in quadriceps limb muscles in aging female mice. However, there was no evidence of an age-related increase in malondialdehyde or F2-isoprostanes levels, which are measures of oxidative damage to lipids, in gastrocnemius muscles. In summary, this study does not support the hypothesis that a pervasive increase in protein thiol oxidation is a contributing factor to sarcopenia. Instead, the data are consistent with an aging theory which proposes that molecular damage to macromolecules leads to the structural and functional disorders associated with aging.
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Affiliation(s)
- Hatice Tohma
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA, Australia
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175
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Vasilaki A, Jackson MJ. Role of reactive oxygen species in the defective regeneration seen in aging muscle. Free Radic Biol Med 2013; 65:317-323. [PMID: 23851030 PMCID: PMC3859734 DOI: 10.1016/j.freeradbiomed.2013.07.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2013] [Revised: 07/03/2013] [Accepted: 07/03/2013] [Indexed: 11/16/2022]
Abstract
The ability of muscles to regenerate successfully following damage diminishes with age and this appears to be a major contributor to the development of muscle weakness and physical frailty. Successful muscle regeneration is dependent on appropriate reinnervation of regenerating muscle. Age-related changes in the interactions between nerve and muscle are poorly understood but may play a major role in the defective regeneration. During aging there is defective redox homeostasis and an accumulation of oxidative damage in nerve and muscle that may contribute to defective regeneration. The aim of this review is to summarise the evidence that abnormal reactive oxygen species (ROS) generation in nerve and/or muscle may be responsible for the defective regeneration that contributes to the degeneration of skeletal muscle observed during aging. Identifying the importance of ROS generation in skeletal muscle during aging could have fundamental implications for interventions to prevent muscle degeneration and treatments to reverse the age-related decline in muscle mass and function.
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Affiliation(s)
- Aphrodite Vasilaki
- MRC-Arthritis Research UK Centre for Integrated Research into Musculoskeletal Ageing, Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L69 3GA, UK.
| | - Malcolm J Jackson
- MRC-Arthritis Research UK Centre for Integrated Research into Musculoskeletal Ageing, Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L69 3GA, UK
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176
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Sullivan-Gunn MJ, Lewandowski PA. Elevated hydrogen peroxide and decreased catalase and glutathione peroxidase protection are associated with aging sarcopenia. BMC Geriatr 2013; 13:104. [PMID: 24093947 PMCID: PMC3853025 DOI: 10.1186/1471-2318-13-104] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 09/30/2013] [Indexed: 12/22/2022] Open
Abstract
Background Sarcopenia is the progressive loss of skeletal muscle that contributes to the decline in physical function during aging. A higher level of oxidative stress has been implicated in aging sarcopenia. The current study aims to determine if the higher level of oxidative stress is a result of increased superoxide (O2‾) production by the NADPH oxidase (NOX) enzyme or decrease in endogenous antioxidant enzyme protection. Methods Female Balb/c mice were assigned to 4 age groups; 6, 12, 18 and 24 months. Body weight and animal survival rates were recorded over the course of the study. Skeletal muscle tissues were collected and used to measure NOX subunit mRNA, O2‾ levels and antioxidant enzymes. Results Key subunit components of NOX expression were elevated in skeletal muscle at 18 months, when sarcopenia was first evident. Increased superoxide dismutase 1 (SOD1) activity suggests an increase in O2‾ dismutation and this was further supported by elevated levels of hydrogen peroxide (H2O2) and decline in catalase and glutathione peroxidase (GPx) antioxidant protection in skeletal muscle at this time. NOX expression was also higher in skeletal muscle at 24 months, however this was coupled with elevated levels of O2‾ and a decline in SOD1 activity, compared to 6 and 12 months but was not associated with further loss of muscle mass. Conclusions While the source of ROS in sarcopenic muscle remains unknown, this study provides evidence that the NOX enzyme could be involved in ROS production by regulating superoxide in ageing muscles. This study also suggests that H2O2 is the key ROS in the onset of sarcopenia and that the decline in antioxidant protection by catalase and GPx is indicative of antioxidant dysfunction and may therefore be a major contributing factor in the development or onset of sarcopenia. Furthermore, the changes in ROS and antioxidant activity after sarcopenia was first evident gives some evidence for a compensatory mechanism, in response to insult, in order to maintain muscle integrity.
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177
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Konigsberg M, Pérez VI, Ríos C, Liu Y, Lee S, Shi Y, Van Remmen H. Effect of oxygen tension on bioenergetics and proteostasis in young and old myoblast precursor cells. Redox Biol 2013; 1:475-82. [PMID: 24191243 PMCID: PMC3814963 DOI: 10.1016/j.redox.2013.09.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 09/10/2013] [Accepted: 09/11/2013] [Indexed: 12/27/2022] Open
Abstract
In the majority of studies using primary cultures of myoblasts, the cells are maintained at ambient oxygen tension (21% O2), despite the fact that physiological O2 at the tissue level in vivo is much lower (~1–5% O2). We hypothesized that the cellular response in presence of high oxygen concentration might be particularly important in studies comparing energetic function or oxidative stress in cells isolated from young versus old animals. To test this, we asked whether oxygen tension plays a role in mitochondrial bioenergetics (oxygen consumption, glycolysis and fatty acid oxidation) or oxidative damage to proteins (protein disulfides, carbonyls and aggregates) in myoblast precursor cells (MPCs) isolated from young (3–4 m) and old (29–30 m) C57BL/6 mice. MPCs were grown under physiological (3%) or ambient (21%) O2 for two weeks prior to exposure to an acute oxidative insult (H2O2). Our results show significantly higher basal mitochondrial respiration in young versus old MPCs, an increase in basal respiration in young MPCs maintained at 3% O2 compared to cells maintained at 21% O2, and a shift toward glycolytic metabolism in old MPCs grown at 21% O2. H2O2 treatment significantly reduced respiration in old MPCs grown at 3% O2 but did not further repress respiration at 21% O2 in old MPCs. Oxidative damage to protein was higher in cells maintained at 21% O2 and increased in response to H2O2 in old MPCs. These data underscore the importance of understanding the effect of ambient oxygen tension in cell culture studies, in particular studies measuring oxidative damage and mitochondrial function. Myoblast precursor cells (MPC) were isolated from old and young mice. The effect of ambient (21%) or physiological (3%) O2 tension on MPCs was addressed. Mitochondrial bioenergetics after H2O2 insult was determined regards to age. 3% O2 induces old MPCs to shift from glycolysis toward oxidative phosphorylation. Protein oxidative damage was higher in old MPCs at 21% O2.
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Affiliation(s)
- M Konigsberg
- Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center, San Antonio, TX 78229, USA ; Universidad Autonoma Metropolitana-Iztapalpa, Mexico City, Mexico
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178
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Jackson MJ. Interactions between reactive oxygen species generated by contractile activity and aging in skeletal muscle? Antioxid Redox Signal 2013; 19:804-12. [PMID: 23682926 PMCID: PMC3749718 DOI: 10.1089/ars.2013.5383] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
SIGNIFICANCE Aging leads to a loss of skeletal muscle mass and function that causes instability, increased risk of falls, and need for residential care. This is due to a reduction in the muscle mass and strength that is primarily due caused by a decrease in the number of muscle fibers, particularly, type II fibers, and atrophy and weakening of those remaining. RECENT ADVANCES Although increased oxidative damage was originally thought to be the key to the aging process, data now indicate that reactive oxygen species (ROS) may be one of the several components of the degenerative processes in aging. The skeletal muscle shows important rapid adaptations to the ROS generated by contractions that are attenuated in aged organisms and transgenic studies have indicated that overcoming these attenuated responses can prevent the age-related loss of muscle mass and function. CRITICAL ISSUES Elucidation of the mechanisms by which the skeletal muscle adapts to the ROS generated to contractions and the way in which these processes are attenuated by aging is critical to the development of logical approaches to prevent age-related loss of muscle mass and function. FUTURE DIRECTIONS Future studies are likely to focus on the redox regulation of adaptive pathways and their maintenance during aging as an approach to maintain and improve muscle function.
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Affiliation(s)
- Malcolm J Jackson
- MRC-Arthritis Research UK Centre for Integrated Research into Musculoskeletal Ageing CIMA, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool L69 3GA, United Kingdom.
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179
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McGoldrick P, Joyce PI, Fisher EMC, Greensmith L. Rodent models of amyotrophic lateral sclerosis. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1832:1421-36. [PMID: 23524377 DOI: 10.1016/j.bbadis.2013.03.012] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Revised: 03/11/2013] [Accepted: 03/12/2013] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterised by the degeneration of upper and lower motor neurons. Recent advances in our understanding of some of the genetic causes of ALS, such as mutations in SOD1, TARDBP, FUS and VCP have led to the generation of rodent models of the disease, as a strategy to help our understanding of the pathophysiology of ALS and to assist in the development of therapeutic strategies. This review provides detailed descriptions of TDP-43, FUS and VCP models of ALS, and summarises potential therapeutics which have been recently trialled in rodent models of the disease. This article is part of a Special Issue entitled: Animal Models of Disease.
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Affiliation(s)
- Philip McGoldrick
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, WC1N 3BG, UK.
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180
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Larkin LM, Hanes MC, Kayupov E, Claflin DR, Faulkner JA, Brooks SV. Weakness of whole muscles in mice deficient in Cu, Zn superoxide dismutase is not explained by defects at the level of the contractile apparatus. AGE (DORDRECHT, NETHERLANDS) 2013; 35:1173-1181. [PMID: 22696118 PMCID: PMC3705120 DOI: 10.1007/s11357-012-9441-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 05/21/2012] [Indexed: 06/01/2023]
Abstract
Mice deficient in Cu,Zn superoxide dismutase (Sod1 (-/-) mice) demonstrate elevated oxidative stress associated with rapid age-related declines in muscle mass and force. The decline in mass for muscles of Sod1 (-/-) mice is explained by a loss of muscle fibers, but the mechanism underlying the weakness is not clear. We hypothesized that the reduced maximum isometric force (F o) normalized by cross-sectional area (specific F o) for whole muscles of Sod1 (-/-) compared with wild-type (WT) mice is due to decreased specific F o of individual fibers. Force generation was measured for permeabilized fibers from muscles of Sod1 (-/-) and WT mice at 8 and 20 months of age. WT mice were also studied at 28 months to determine whether any deficits observed for fibers from Sod1 (-/-) mice were similar to those observed in old WT mice. No effects of genotype were observed for F o or specific F o at either 8 or 20 months, and no age-associated decrease in specific F o was observed for fibers from Sod1 (-/-) mice, whereas specific F o for fibers of WT mice decreased by 20 % by 28 months. Oxidative stress has also been associated with decreased maximum velocity of shortening (V max), and we found a 10 % lower V max for fibers from Sod1 (-/-) compared with WT mice at 20 months. We conclude that the low specific F o of muscles of Sod1 (-/-) mice is not explained by damage to contractile proteins. Moreover, the properties of fibers of Sod1 (-/-) mice do not recapitulate those observed with aging in WT animals.
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Affiliation(s)
- Lisa M. Larkin
- />Departments of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109-2200 USA
- />Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 USA
| | - Michael C. Hanes
- />Departments of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109-2200 USA
| | - Erdan Kayupov
- />Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 USA
| | - Dennis R. Claflin
- />Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 USA
- />Surgery, Section of Plastic Surgery, University of Michigan, Ann Arbor, MI 48109 USA
| | - John A. Faulkner
- />Departments of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109-2200 USA
- />Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 USA
| | - Susan V. Brooks
- />Departments of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109-2200 USA
- />Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 USA
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181
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Gouspillou G, Picard M, Godin R, Burelle Y, Hepple RT. Role of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) in denervation-induced atrophy in aged muscle: facts and hypotheses. LONGEVITY & HEALTHSPAN 2013; 2:13. [PMID: 24472348 PMCID: PMC3922934 DOI: 10.1186/2046-2395-2-13] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Accepted: 06/19/2013] [Indexed: 12/25/2022]
Abstract
Aging-related loss of muscle mass, a biological process named sarcopenia, contributes to mobility impairment, falls, and physical frailty, resulting in an impaired quality of life in older people. In view of the aging of our society, understanding the underlying mechanisms of sarcopenia is a major health-care imperative. Evidence obtained from human and rodent studies demonstrates that skeletal muscle denervation/reinnervation cycles occur with aging, and that progressive failure of myofiber reinnervation is a major cause of the accelerating phase of sarcopenia in advanced age. However, the mechanisms responsible for the loss of myofiber innervation with aging remain unknown. The two major strategies that counteract sarcopenia, that is, caloric restriction and endurance training, are well known to protect neuromuscular junction (NMJ) integrity, albeit through undefined mechanisms. Interestingly, both of these interventions better preserve PGC-1α expression with aging, a transcriptional coactivator which has recently been shown to regulate key proteins involved in maintaining NMJ integrity. We therefore propose that the aging-related decline in PGC-1α may be a central mechanism promoting instability of the NMJ and consequently, aging-related alterations of myofiber innervation in sarcopenia. Similarly, the promotion of PGC-1α expression by both caloric restriction and exercise training may be fundamental to their protective benefits for aging muscle by better preserving NMJ integrity.
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Affiliation(s)
| | | | | | | | - Russell T Hepple
- Department of Critical Care, McGill University Health Centre, 687 Pine Ave West, Montreal, QC H3A 1A1, Canada.
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182
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Nedergaard A, Henriksen K, Karsdal MA, Christiansen C. Musculoskeletal ageing and primary prevention. Best Pract Res Clin Obstet Gynaecol 2013; 27:673-88. [PMID: 23891483 DOI: 10.1016/j.bpobgyn.2013.06.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 05/17/2013] [Accepted: 06/10/2013] [Indexed: 12/12/2022]
Abstract
Loss of musculoskeletal mass and function is a natural ageing trait, reinforced by an unhealthy life style. Loss of bone (osteoporosis) and muscle (sarcopaenia) are conditions whose prevalence are increasing because of the change in population distribution in the western world towards an older mean age. Improvements in lifestyle factors, such as diet, smoking and exercise, are the most powerful tools to combat this decline efficiently; however, public health interventions aimed at tackling these problems have shown abysmal success at the population level, mostly due to failure in compliance. With these issues in mind, we believe that the primary prevention modality in coming decades will be pharmacological. We review the basic biology of musculoskeletal ageing and what measures can be taken to prevent ageing-associated loss of musculoskeletal mass and function, with particular emphasis on pharmacological means.
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Affiliation(s)
- Anders Nedergaard
- Nordic Bioscience Biomarkers and Research, Herlev Hovedgade 207, 2720 Herlev, Denmark; Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Building 8, Bispebjerg Bakke 23, 2400 Copenhagen NW, Denmark.
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183
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Sims-Robinson C, Hur J, Hayes JM, Dauch JR, Keller PJ, Brooks SV, Feldman EL. The role of oxidative stress in nervous system aging. PLoS One 2013; 8:e68011. [PMID: 23844146 PMCID: PMC3699525 DOI: 10.1371/journal.pone.0068011] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 05/23/2013] [Indexed: 12/22/2022] Open
Abstract
While oxidative stress is implicated in aging, the impact of oxidative stress on aging in the peripheral nervous system is not well understood. To determine a potential mechanism for age-related deficits in the peripheral nervous system, we examined both functional and morphological changes and utilized microarray technology to compare normal aging in wild-type mice to effects in copper/zinc superoxide dismutase-deficient (Sod1(-/-)) mice, a mouse model of increased oxidative stress. Sod1(-/-) mice exhibit a peripheral neuropathy phenotype with normal sensory nerve function and deficits in motor nerve function. Our data indicate that a decrease in the synthesis of cholesterol, which is vital to myelin formation, correlates with the structural deficits in axons, myelin, and the cell body of motor neurons in the Sod1(+/+) mice at 30 months and the Sod1(-/-) mice at 20 months compared with mice at 2 months. Collectively, we have demonstrated that the functional and morphological changes within the peripheral nervous system in our model of increased oxidative stress are manifested earlier and resemble the deficits observed during normal aging.
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Affiliation(s)
- Catrina Sims-Robinson
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Junguk Hur
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - John M. Hayes
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Jacqueline R. Dauch
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Peter J. Keller
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Susan V. Brooks
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Eva L. Feldman
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
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184
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Vinsant S, Mansfield C, Jimenez-Moreno R, Del Gaizo Moore V, Yoshikawa M, Hampton TG, Prevette D, Caress J, Oppenheim RW, Milligan C. Characterization of early pathogenesis in the SOD1(G93A) mouse model of ALS: part II, results and discussion. Brain Behav 2013; 3:431-57. [PMID: 24381813 PMCID: PMC3869683 DOI: 10.1002/brb3.142] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 03/21/2013] [Accepted: 03/22/2013] [Indexed: 12/12/2022] Open
Abstract
Pathological events are well characterized in amyotrophic lateral sclerosis (ALS) mouse models, but review of the literature fails to identify a specific initiating event that precipitates disease pathology. There is now growing consensus in the field that axon and synapses are first cellular sites of degeneration, but controversy exists over whether axon and synapse loss is initiated autonomously at those sites or by pathology in the cell body, in nonneuronal cells or even in nonmotoneurons (MNs). Previous studies have identified pathological events in the mutant superoxide dismutase 1 (SOD1) models involving spinal cord, peripheral axons, neuromuscular junctions (NMJs), or muscle; however, few studies have systematically examined pathogenesis at multiple sites in the same study. We have performed ultrastructural examination of both central and peripheral components of the neuromuscular system in the SOD1(G93A) mouse model of ALS. Twenty percent of MNs undergo degeneration by P60, but NMJ innervation in fast fatigable muscles is reduced by 40% by P30. Gait alterations and muscle weakness were also found at P30. There was no change in axonal transport prior to initial NMJ denervation. Mitochondrial morphological changes are observed at P7 and become more prominent with disease progression. At P30 there was a significant decrease in excitatory axo-dendritic and axo-somatic synapses with an increase in C-type axo-somatic synapses. Our study examined early pathology in both peripheral and central neuromuscular system. The muscle denervation is associated with functional motor deficits and begins during the first postnatal month in SOD1(G93A) mice. Physiological dysfunction and pathology in the mitochondria of synapses and MN soma and dendrites occur, and disease onset in these animals begins more than 2 months earlier than originally thought. This information may be valuable for designing preclinical trials that are more likely to impact disease onset and progression.
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Affiliation(s)
- Sharon Vinsant
- Department of Neurobiology and Anatomy, The Neuroscience Program and The ALS Center, Wake Forest University School of Medicine Winston-Salem, North Carolina
| | - Carol Mansfield
- Department of Neurobiology and Anatomy, The Neuroscience Program and The ALS Center, Wake Forest University School of Medicine Winston-Salem, North Carolina
| | - Ramon Jimenez-Moreno
- Department of Neurobiology and Anatomy, The Neuroscience Program and The ALS Center, Wake Forest University School of Medicine Winston-Salem, North Carolina
| | | | - Masaaki Yoshikawa
- Department of Neurobiology and Anatomy, The Neuroscience Program and The ALS Center, Wake Forest University School of Medicine Winston-Salem, North Carolina
| | | | - David Prevette
- Department of Neurobiology and Anatomy, The Neuroscience Program and The ALS Center, Wake Forest University School of Medicine Winston-Salem, North Carolina
| | - James Caress
- Department of Neurology and the ALS Center, Wake Forest University School of Medicine Winston-Salem, North Carolina
| | - Ronald W Oppenheim
- Department of Neurobiology and Anatomy, The Neuroscience Program and The ALS Center, Wake Forest University School of Medicine Winston-Salem, North Carolina
| | - Carol Milligan
- Department of Neurobiology and Anatomy, The Neuroscience Program and The ALS Center, Wake Forest University School of Medicine Winston-Salem, North Carolina
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185
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Zhang Y, Ikeno Y, Bokov A, Gelfond J, Jaramillo C, Zhang HM, Liu Y, Qi W, Hubbard G, Richardson A, Van Remmen H. Dietary restriction attenuates the accelerated aging phenotype of Sod1(-/-) mice. Free Radic Biol Med 2013; 60:300-6. [PMID: 23459073 PMCID: PMC3696984 DOI: 10.1016/j.freeradbiomed.2013.02.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 02/16/2013] [Accepted: 02/21/2013] [Indexed: 02/06/2023]
Abstract
Dietary restriction is a powerful aging intervention that extends the life span of diverse biological species ranging from yeast to invertebrates to mammals, and it has been argued that the antiaging action of dietary restriction occurs through reduced oxidative stress/damage. Using Sod1(-/-) mice, which have previously been shown to have increased levels of oxidative stress associated with a shorter life span and a high incidence of neoplasia, we were able to test directly the ability of dietary restriction to reverse an aging phenotype due to increased oxidative stress/damage. We found that dietary restriction increased the life span of Sod1(-/-) mice 30%, returning it to that of wild-type, control mice fed ad libitum. Oxidative damage in Sod1(-/-) mice was markedly reduced by dietary restriction, as indicated by a reduction in liver and brain F2-isoprostanes, a marker of lipid peroxidation. Analysis of end of life pathology showed that dietary restriction significantly reduced the overall incidence of pathological lesions in the Sod1(-/-) mice fed the dietary-restricted diet compared to Sod1(-/-) mice fed ad libitum, including the incidence of lymphoma (27 vs 5%) and overall liver pathology. In addition to reduced incidence of overall and liver-specific pathology, the burden and severity of both neoplastic and nonneoplastic lesions was also significantly reduced in the Sod1(-/-) mice fed the dietary-restricted diet. These data demonstrate that dietary restriction can significantly attenuate the accelerated aging phenotype observed in Sod1(-/-) mice that arises from increased oxidative stress/damage.
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Affiliation(s)
- Yiqiang Zhang
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
| | - Yuji Ikeno
- Department of Pathology, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
- Geriatric Education, Clinical, and Research Center at the South Texas Veterans Health Care System, San Antonio, Texas 78229-7762, USA
| | - Alex Bokov
- Department of Epidemiology and Biostatistics, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
| | - Jon Gelfond
- Department of Epidemiology and Biostatistics, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
| | - Carlos Jaramillo
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
| | - Hong-Mei Zhang
- Department of Clinical Oncology, Xijing Hospital, The Fourth Military Medical University, Xi’an, China
| | - Yuhong Liu
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
| | - Wenbo Qi
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
| | - Gene Hubbard
- Department of Pathology, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
| | - Arlan Richardson
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
- Geriatric Education, Clinical, and Research Center at the South Texas Veterans Health Care System, San Antonio, Texas 78229-7762, USA
| | - Holly Van Remmen
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78229-3900, USA
- Geriatric Education, Clinical, and Research Center at the South Texas Veterans Health Care System, San Antonio, Texas 78229-7762, USA
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186
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Hamilton RT, Bhattacharya A, Walsh ME, Shi Y, Wei R, Zhang Y, Rodriguez KA, Buffenstein R, Chaudhuri AR, Van Remmen H. Elevated protein carbonylation, and misfolding in sciatic nerve from db/db and Sod1(-/-) mice: plausible link between oxidative stress and demyelination. PLoS One 2013; 8:e65725. [PMID: 23750273 PMCID: PMC3672154 DOI: 10.1371/journal.pone.0065725] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Accepted: 04/27/2013] [Indexed: 11/19/2022] Open
Abstract
Diabetic peripheral polyneuropathy is associated with decrements in motor/sensory neuron myelination, nerve conduction and muscle function; however, the mechanisms of reduced myelination in diabetes are poorly understood. Chronic elevation of oxidative stress may be one of the potential determinants for demyelination as lipids and proteins are important structural constituents of myelin and highly susceptible to oxidation. The goal of the current study was to determine whether there is a link between protein oxidation/misfolding and demyelination. We chose two distinct models to test our hypothesis: 1) the leptin receptor deficient mouse (dbdb) model of diabetic polyneuropathy and 2) superoxide dismutase 1 knockout (Sod1(-/-) ) mouse model of in vivo oxidative stress. Both experimental models displayed a significant decrement in nerve conduction, increase in tail distal motor latency as well as reduced myelin thickness and fiber/axon diameter. Further biochemical studies demonstrated that oxidative stress is likely to be a potential key player in the demyelination process as both models exhibited significant elevation in protein carbonylation and alterations in protein conformation. Since peripheral myelin protein 22 (PMP22) is a key component of myelin sheath and has been found mutated and aggregated in several peripheral neuropathies, we predicted that an increase in carbonylation and aggregation of PMP22 may be associated with demyelination in dbdb mice. Indeed, PMP22 was found to be carbonylated and aggregated in sciatic nerves of dbdb mice. Sequence-driven hydropathy plot analysis and in vitro oxidation-induced aggregation of purified PMP22 protein supported the premise for oxidation-dependent aggregation of PMP22 in dbdb mice. Collectively, these data strongly suggest for the first time that oxidation-mediated protein misfolding and aggregation of key myelin proteins may be linked to demyelination and reduced nerve conduction in peripheral neuropathies.
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Affiliation(s)
- Ryan T. Hamilton
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, Texas, United States of America
- Sam and Ann Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, United States of America
| | - Arunabh Bhattacharya
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, Texas, United States of America
- Sam and Ann Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, United States of America
| | - Michael E. Walsh
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, Texas, United States of America
| | - Yun Shi
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, Texas, United States of America
- Sam and Ann Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, United States of America
| | - Rochelle Wei
- Sam and Ann Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, United States of America
| | - Yiqiang Zhang
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, Texas, United States of America
- Sam and Ann Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, United States of America
| | - Karl A. Rodriguez
- Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America
- Sam and Ann Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, United States of America
| | - Rochelle Buffenstein
- Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America
- Sam and Ann Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, United States of America
| | - Asish R. Chaudhuri
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, Texas, United States of America
- Sam and Ann Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, United States of America
- Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, United States of America
- * E-mail: (ARC); (HV)
| | - Holly Van Remmen
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, Texas, United States of America
- Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America
- Sam and Ann Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, United States of America
- Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, United States of America
- * E-mail: (ARC); (HV)
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187
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Zhang Y, Davis C, Sakellariou GK, Shi Y, Kayani AC, Pulliam D, Bhattacharya A, Richardson A, Jackson MJ, McArdle A, Brooks SV, Van Remmen H. CuZnSOD gene deletion targeted to skeletal muscle leads to loss of contractile force but does not cause muscle atrophy in adult mice. FASEB J 2013; 27:3536-48. [PMID: 23729587 DOI: 10.1096/fj.13-228130] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We have previously shown that deletion of CuZnSOD in mice (Sod1(-/-) mice) leads to accelerated loss of muscle mass and contractile force during aging. To dissect the relative roles of skeletal muscle and motor neurons in this process, we used a Cre-Lox targeted approach to establish a skeletal muscle-specific Sod1-knockout (mKO) mouse to determine whether muscle-specific CuZnSOD deletion is sufficient to cause muscle atrophy. Surprisingly, mKO mice maintain muscle masses at or above those of wild-type control mice up to 18 mo of age. In contrast, maximum isometric specific force measured in gastrocnemius muscle is significantly reduced in the mKO mice. We found no detectable increases in global measures of oxidative stress or ROS production, no reduction in mitochondrial ATP production, and no induction of adaptive stress responses in muscle from mKO mice. However, Akt-mTOR signaling is elevated and the number of muscle fibers with centrally located nuclei is increased in skeletal muscle from mKO mice, which suggests elevated regenerative pathways. Our data demonstrate that lack of CuZnSOD restricted to skeletal muscle does not lead to muscle atrophy but does cause muscle weakness in adult mice and suggest loss of CuZnSOD may potentiate muscle regenerative pathways.
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Affiliation(s)
- Yiqiang Zhang
- Department of Physiology, University of Texas Health Science Center, San Antonio, Texas 78249, USA
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188
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Saccon RA, Bunton-Stasyshyn RKA, Fisher EMC, Fratta P. Is SOD1 loss of function involved in amyotrophic lateral sclerosis? ACTA ACUST UNITED AC 2013; 136:2342-58. [PMID: 23687121 PMCID: PMC3722346 DOI: 10.1093/brain/awt097] [Citation(s) in RCA: 215] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mutations in the gene superoxide dismutase 1 (SOD1) are causative for familial forms of the neurodegenerative disease amyotrophic lateral sclerosis. When the first SOD1 mutations were identified they were postulated to give rise to amyotrophic lateral sclerosis through a loss of function mechanism, but experimental data soon showed that the disease arises from a—still unknown—toxic gain of function, and the possibility that loss of function plays a role in amyotrophic lateral sclerosis pathogenesis was abandoned. Although loss of function is not causative for amyotrophic lateral sclerosis, here we re-examine two decades of evidence regarding whether loss of function may play a modifying role in SOD1–amyotrophic lateral sclerosis. From analysing published data from patients with SOD1–amyotrophic lateral sclerosis, we find a marked loss of SOD1 enzyme activity arising from almost all mutations. We continue to examine functional data from all Sod1 knockout mice and we find obvious detrimental effects within the nervous system with, interestingly, some specificity for the motor system. Here, we bring together historical and recent experimental findings to conclude that there is a possibility that SOD1 loss of function may play a modifying role in amyotrophic lateral sclerosis. This likelihood has implications for some current therapies aimed at knocking down the level of mutant protein in patients with SOD1–amyotrophic lateral sclerosis. Finally, the wide-ranging phenotypes that result from loss of function indicate that SOD1 gene sequences should be screened in diseases other than amyotrophic lateral sclerosis.
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Affiliation(s)
- Rachele A Saccon
- Department of Neurodegenerative Disease, Institute of Neurology, University College, London WC1N 3BG, UK
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189
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Age-dependent alteration in muscle regeneration: the critical role of tissue niche. Biogerontology 2013; 14:273-92. [PMID: 23666344 PMCID: PMC3719007 DOI: 10.1007/s10522-013-9429-4] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 04/29/2013] [Indexed: 12/31/2022]
Abstract
Although adult skeletal muscle is composed of fully differentiated fibers, it retains the capacity to regenerate in response to injury and to modify its contractile and metabolic properties in response to changing demands. The major role in the growth, remodeling and regeneration is played by satellite cells, a quiescent population of myogenic precursor cells that reside between the basal lamina and plasmalemma and that are rapidly activated in response to appropriate stimuli. However, in pathologic conditions or during aging, the complete regenerative program can be precluded by fibrotic tissue formation and resulting in functional impairment of the skeletal muscle. Our study, along with other studies, demonstrated that although the regenerative program can also be impaired by the limited proliferative capacity of satellite cells, this limit is not reached during normal aging, and it is more likely that the restricted muscle repair program in aging is presumably due to missing signals that usually render the damaged muscle a permissive environment for regenerative activity.
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190
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García ML, Fernández A, Solas MT. Mitochondria, motor neurons and aging. J Neurol Sci 2013; 330:18-26. [PMID: 23628465 DOI: 10.1016/j.jns.2013.03.019] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 03/21/2013] [Accepted: 03/26/2013] [Indexed: 02/06/2023]
Abstract
While the role of mitochondria in aging has been well characterized, their involvement in motor neuron aging remains poorly understood. Thus, we performed an exhaustive ultrastructural study of mitochondria in motor neurons from aged rats that revealed dramatic alterations in the mitochondria of axon terminals at neuromuscular junctions, characterized by swelling, mitochondrial fusion and the presence of megamitochondria. These alterations were not observed in ventral horn motor neurons in the spinal cord of aged rats, which were only altered by the appearance of electron-dense bodies in the dilated matrix cristae. Using X-ray microanalytical techniques we demonstrated the presence of calcium in these bodies, suggesting Ca(2+) overload. Moreover, in motor neurons from aged rats, cytochrome c and activated caspase 3 were detected in the cytoplasm of axon terminals at neuromuscular junctions, factors implicated in the apoptosis. Active caspase 3 was also found in the nucleus, soma and axons of aged alpha motor neuron neurons, where it mainly associated with microtubules. The colocalization of dynein and cleaved caspase 3 in neuromuscular junctions is strongly suggestive of the retrograde transport of apoptotic factors to the soma. These results are consistent with the early stages of degeneration in neuromuscular junctions during aging, which is followed by dying back. Given that aging is a key risk factor for neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS), the identification of age-related motor neuron degeneration initiated at the distal end of the axon may provide a new therapeutic target for early intervention.
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Affiliation(s)
- M L García
- Centro Nacional de Microscopía Electrónica University Complutense of Madrid, Spain.
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191
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Gouspillou G, Hepple RT. Facts and controversies in our understanding of how caloric restriction impacts the mitochondrion. Exp Gerontol 2013; 48:1075-84. [PMID: 23523973 DOI: 10.1016/j.exger.2013.03.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 02/26/2013] [Accepted: 03/11/2013] [Indexed: 12/11/2022]
Abstract
Caloric restriction (CR) has pronounced benefits in promoting healthy aging. Amongst the most frequently implicated physiological mechanisms implicated in this benefit is altered mitochondrial function. Whereas a reduction in mitochondrial reactive oxygen species (ROS) production is a widely consistent effect of CR, an increase in mitochondrial biogenesis, which is accepted by many as fact, is contradicted on several levels, most critically by a lack of increase in mitochondrial protein synthesis rate in vivo. Furthermore, an increase in PGC-1α protein and markers of mitochondrial content with CR is a highly variable observation between studies. On the other hand, deacetylation of several mitochondrial proteins by the sirtuin, Sirt3, is an increasingly reported observation and at least so far, this observation is consistent between studies. Notwithstanding this point, the controversies evident in the published literature underscore the significant questions that remain in our understanding of how CR impacts the mitochondrion and suggest we have yet to fully understand the complexities herein.
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Affiliation(s)
- Gilles Gouspillou
- McGill University Health Center, Department of Kinesiology, McGill University, Montreal, QC, Canada
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192
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Deepa SS, Pulliam D, Hill S, Shi Y, Walsh ME, Salmon A, Sloane L, Zhang N, Zeviani M, Viscomi C, Musi N, Van Remmen H. Improved insulin sensitivity associated with reduced mitochondrial complex IV assembly and activity. FASEB J 2012; 27:1371-80. [PMID: 23241310 DOI: 10.1096/fj.12-221879] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Mice lacking Surf1, a complex IV assembly protein, have ∼50-70% reduction in cytochrome c oxidase activity in all tissues yet a paradoxical increase in lifespan. Here we report that Surf1(-/-) mice have lower body (15%) and fat (20%) mass, in association with reduced lipid storage, smaller adipocytes, and elevated indicators of fatty acid oxidation in white adipose tissue (WAT) compared with control mice. The respiratory quotient in the Surf1(-/-) mice was significantly lower than in the control animals (0.83-0.93 vs. 0.90-0.98), consistent with enhanced fat utilization in Surf1(-/-) mice. Elevated fat utilization was associated with increased insulin sensitivity measured as insulin-stimulated glucose uptake, as well as an increase in insulin receptor levels (∼2-fold) and glucose transporter type 4 (GLUT4; ∼1.3-fold) levels in WAT in the Surf1(-/-) mice. The expression of peroxisome proliferator-activated receptor γ-coactivator 1-α (PGC-1α) mRNA and protein was up-regulated by 2.5- and 1.9-fold, respectively, in WAT from Surf1(-/-) mice, and the expression of PGC-1α target genes and markers of mitochondrial biogenesis was elevated. Together, these findings point to a novel and unexpected link between reduced mitochondrial complex IV activity, enhanced insulin sensitivity, and increased mitochondrial biogenesis that may contribute to the increased longevity in the Surf1(-/-) mice.
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Affiliation(s)
- Sathyaseelan S Deepa
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center, San Antonio, TX78245, USA
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193
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Ungvari Z, Sosnowska D, Mason JB, Gruber H, Lee SW, Schwartz TS, Brown MK, Storm NJ, Fortney K, Sowa J, Byrne AB, Kurz T, Levy E, Sonntag WE, Austad SN, Csiszar A, Ridgway I. Resistance to genotoxic stresses in Arctica islandica, the longest living noncolonial animal: is extreme longevity associated with a multistress resistance phenotype? J Gerontol A Biol Sci Med Sci 2012; 68:521-9. [PMID: 23051979 DOI: 10.1093/gerona/gls193] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Bivalve molluscs are newly discovered models of successful aging. Here, we test the hypothesis that extremely long-lived bivalves are not uniquely resistant to oxidative stressors (eg, tert-butyl hydroperoxide, as demonstrated in previous studies) but exhibit a multistress resistance phenotype. We contrasted resistance (in terms of organismal mortality) to genotoxic stresses (including topoisomerase inhibitors, agents that cross-link DNA or impair genomic integrity through DNA alkylation or methylation) and to mitochondrial oxidative stressors in three bivalve mollusc species with dramatically differing life spans: Arctica islandica (ocean quahog), Mercenaria mercenaria (northern quahog), and the Atlantic bay scallop, Argopecten irradians irradians (maximum species life spans: >500, >100, and ~2 years, respectively). With all stressors, the short-lived A i irradians were significantly less resistant than the two longer lived species. Arctica islandica were consistently more resistant than M mercenaria to mortality induced by oxidative stressors as well as DNA methylating agent nitrogen mustard and the DNA alkylating agent methyl methanesulfonate. The same trend was not observed for genotoxic agents that act through cross-linking DNA. In contrast, M mercenaria tended to be more resistant to epirubicin and genotoxic stressors, which cause DNA damage by inhibiting topoisomerases. To our knowledge, this is the first study comparing resistance to genotoxic stressors in bivalve mollusc species with disparate longevities. In line with previous studies of comparative stress resistance and longevity, our data extends, at least in part, the evidence for the hypothesis that an association exists between longevity and a general resistance to multiplex stressors, not solely oxidative stress. This work also provides justification for further investigation into the interspecies differences in stress response signatures induced by a diverse array of stressors in short-lived and long-lived bivalves, including pharmacological agents that elicit endoplasmic reticulum stress and cellular stress caused by activation of innate immunity.
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Affiliation(s)
- Zoltan Ungvari
- 1Reynolds Oklahoma Center on Aging, Donald W. Reynolds Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
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194
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Jang YC, Liu Y, Hayworth CR, Bhattacharya A, Lustgarten MS, Muller FL, Chaudhuri A, Qi W, Li Y, Huang JY, Verdin E, Richardson A, Van Remmen H. Dietary restriction attenuates age-associated muscle atrophy by lowering oxidative stress in mice even in complete absence of CuZnSOD. Aging Cell 2012; 11:770-82. [PMID: 22672615 DOI: 10.1111/j.1474-9726.2012.00843.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Age-related loss of muscle mass and function, sarcopenia, has a major impact on the quality of life in the elderly. Among the proposed causes of sarcopenia are mitochondrial dysfunction and accumulated oxidative damage during aging. Dietary restriction (DR), a robust dietary intervention that extends lifespan and modulates age-related pathology in a variety of species, has been shown to protect from sarcopenia in rodents. Although the mechanism(s) by which DR modulates aging are still not defined, one potential mechanism is through modulation of oxidative stress and mitochondrial dysfunction. To directly test the protective effect of DR against oxidative stress-induced muscle atrophy in vivo, we subjected mice lacking a key antioxidant enzyme, CuZnSOD (Sod1) to DR (60% of ad libitum fed diet). We have previously shown that the Sod1(-/-) mice exhibit an acceleration of sarcopenia associated with high oxidative stress, mitochondrial dysfunction, and severe neuromuscular innervation defects. Despite the dramatic atrophy phenotype in the Sod1(-/-) mice, DR led to a reversal or attenuation of reduced muscle function, loss of innervation, and muscle atrophy in these mice. DR improves mitochondrial function as evidenced by enhanced Ca2+ regulation and reduction of mitochondrial reactive oxygen species (ROS). Furthermore, we show upregulation of SIRT3 and MnSOD in DR animals, consistent with reduced mitochondrial oxidative stress and reduced oxidative damage in muscle tissue measured as F2-isoprostanes. Collectively, our results demonstrate that DR is a powerful mediator of mitochondrial function, mitochondrial ROS production, and oxidative damage, providing a solid protection against oxidative stress-induced neuromuscular defects and muscle atrophy in vivo even under conditions of high oxidative stress.
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Affiliation(s)
- Young C Jang
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
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195
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Jackson MJ, McArdle A, Vasilaki A, Kayani A. Workshop report: Can an understanding of the mechanisms underlying age-related loss of muscle mass and function guide exercise and other intervention strategies? LONGEVITY & HEALTHSPAN 2012; 1:5. [PMID: 25599705 PMCID: PMC3886259 DOI: 10.1186/2046-2395-1-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 06/28/2012] [Indexed: 11/10/2022]
Abstract
An international workshop was hosted by the University of Liverpool on 15-16 July 2011 to address at a basic level what is known about the fundamental mechanisms by which skeletal muscle mass and function are lost during aging and to examine the nature of interventions that might prevent these mechanistic changes. Of particular importance was to attempt to evaluate how different forms of exercise (or muscle contractile activity) influence these processes and how these effects can be best optimized to prevent or delay age-related loss of muscle function. The program took the form of a two-day meeting, comprising a series of invited talks and breakout sessions designed to identify key gaps in current knowledge and potential future research questions. The aims of this Workshop were two-fold: 1. To identify the current state-of-the-art in the understanding of the mechanisms that contribute to loss of skeletal muscle mass and function that occurs with aging and to address at a mechanistic level how, and to what extent, exercise and/or other interventions might prevent these changes. 2. To identify specific areas of research where information is sparse but which are likely to yield data that will impact on future strategies to manipulate age-related loss of muscle mass and function in older people. The areas discussed in detail were loss of functional motor units, reduced muscle stem cell activity, age-related changes in transcriptional responses of muscle to exercise and nutrition, age-related changes in protein homeostasis, mitochondrial function, altered cross-talk between muscle with immune cells and how the developments in basic science to understand mechanisms underlying age-related loss of muscle mass and function can be translated. Following each session three key areas where further studies are needed were identified.
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Affiliation(s)
- Malcolm J Jackson
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L69 3GA, UK
| | - Anne McArdle
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L69 3GA, UK
| | - Aphrodite Vasilaki
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L69 3GA, UK
| | - Anna Kayani
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, L69 3GA, UK
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196
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Stefanatos R, Sriram A, Kiviranta E, Mohan A, Ayala V, Jacobs HT, Pamplona R, Sanz A. dj-1β regulates oxidative stress, insulin-like signaling and development in Drosophila melanogaster. Cell Cycle 2012; 11:3876-86. [PMID: 22983063 DOI: 10.4161/cc.22073] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
DJ-1 (or PARK-7) is a multifunctional protein implicated in numerous pathologies including cancer, sterility and Parkinson disease (PD). The popular genetic model Drosophila melanogaster has two orthologs, dj-1: α and β. Dysfunction of dj-1β strongly impairs fly mobility in an age-dependent manner. In this study, we analyze in detail the molecular mechanism underlying the dj-1β mutant phenotype. Mitochondrial hydrogen peroxide production, but not superoxide production, was increased in mutant flies. An increase in peroxide leak from mitochondria causes oxidative damage elsewhere and explains the strong reduction in mobility caused by dj-1β mutation. However, at the same time, increased levels of hydrogen peroxide activated a pro-survival program characterized by (1) an alteration in insulin-like signaling, (2) an increase in mitochondrial biogenesis and (3) an increase in the de-acetylase activity of sirtuins. The activation of this pro-survival program was associated with increased longevity under conditions of moderate oxidative stress. Additionally, the dj-1β mutation unexpectedly accelerated development, a phenotype not previously associated with this mutation. Our results reveal an important role of dj-1β in oxidative stress handling, insulin-like signaling and development in Drosophila melanogaster.
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Affiliation(s)
- Rhoda Stefanatos
- Institute of Biomedical Technology and Tampere University Hospital, University of Tampere, Tampere, Finland
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197
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Sakowski SA, Lunn JS, Busta AS, Oh SS, Zamora-Berridi G, Palmer M, Rosenberg AA, Philip SG, Dowling JJ, Feldman EL. Neuromuscular effects of G93A-SOD1 expression in zebrafish. Mol Neurodegener 2012; 7:44. [PMID: 22938571 PMCID: PMC3506515 DOI: 10.1186/1750-1326-7-44] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 08/26/2012] [Indexed: 12/11/2022] Open
Abstract
Background Amyotrophic lateral sclerosis (ALS) is a fatal disorder involving the degeneration and loss of motor neurons. The mechanisms of motor neuron loss in ALS are unknown and there are no effective treatments. Defects in the distal axon and at the neuromuscular junction are early events in the disease course, and zebrafish provide a promising in vivo system to examine cellular mechanisms and treatments for these events in ALS pathogenesis. Results We demonstrate that transient genetic manipulation of zebrafish to express G93A-SOD1, a mutation associated with familial ALS, results in early defects in motor neuron outgrowth and axonal branching. This is consistent with previous reports on motor neuron axonal defects associated with familial ALS genes following knockdown or mutant protein overexpression. We also demonstrate that upregulation of growth factor signaling is capable of rescuing these early defects, validating the potential of the model for therapeutic discovery. We generated stable transgenic zebrafish lines expressing G93A-SOD1 to further characterize the consequences of G93A-SOD1 expression on neuromuscular pathology and disease progression. Behavioral monitoring reveals evidence of motor dysfunction and decreased activity in transgenic ALS zebrafish. Examination of neuromuscular and neuronal pathology throughout the disease course reveals a loss of neuromuscular junctions and alterations in motor neuron innervations patterns with disease progression. Finally, motor neuron cell loss is evident later in the disease. Conclusions This sequence of events reflects the stepwise mechanisms of degeneration in ALS, and provides a novel model for mechanistic discovery and therapeutic development for neuromuscular degeneration in ALS.
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Affiliation(s)
- Stacey A Sakowski
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor 5017 AAT-BSRBMI, USA
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198
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Abstract
Aging and the physiologic decline of tissues and cells were once thought to be irreversible. However, recent studies suggest that various tissues, especially parts of the hematopoietic system, can be rejuvenated. Here we review potential mechanisms for this process and how they may be used to reverse age-related disorders and aging in general. We propose the novel hypothesis that altering the homeostatic process during cellular depletion can reverse aging in the hematopoietic system.
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199
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Benedusi V, Martorana F, Brambilla L, Maggi A, Rossi D. The peroxisome proliferator-activated receptor γ (PPARγ) controls natural protective mechanisms against lipid peroxidation in amyotrophic lateral sclerosis. J Biol Chem 2012; 287:35899-911. [PMID: 22910911 PMCID: PMC3476258 DOI: 10.1074/jbc.m112.366419] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Recent evidence highlights the peroxisome proliferator-activated receptors (PPARs) as critical neuroprotective factors in several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). To gain new mechanistic insights into the role of these receptors in the context of ALS, here we investigated how PPAR transcriptional activity varies in hSOD1G93A ALS transgenic mice. We demonstrate that PPARγ-driven transcription selectively increases in the spinal cord of symptomatic hSOD1G93A mice. This phenomenon correlates with the up-regulation of target genes, such as lipoprotein lipase and glutathione S-transferase α-2, which are implicated in scavenging lipid peroxidation by-products. Such events are associated with enhanced PPARγ immunoreactivity within motor neuronal nuclei. This observation, and the fact that PPARγ displays increased responsiveness in cultured hSOD1G93A motor neurons, points to a role for this receptor in neutralizing deleterious lipoperoxidation derivatives within the motor cells. Consistently, in both motor neuron-like cultures and animal models, we report that PPARγ is activated by lipid peroxidation end products, such as 4-hydroxynonenal, whose levels are elevated in the cerebrospinal fluid and spinal cord from ALS patients. We propose that the accumulation of critical concentrations of lipid peroxidation adducts during ALS progression leads to the activation of PPARγ in motor neurons. This in turn triggers self-protective mechanisms that involve the up-regulation of lipid detoxification enzymes, such as lipoprotein lipase and glutathione S-transferase α-2. Our findings indicate that anticipating natural protective reactions by pharmacologically modulating PPARγ transcriptional activity may attenuate neurodegeneration by limiting the damage induced by lipid peroxidation derivatives.
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Affiliation(s)
- Valeria Benedusi
- Center of Excellence on Neurodegenerative Diseases and Department of Pharmacological and Biomolecular Sciences, University of Milan, 20133 Milan, Italy
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200
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Siegel MP, Wilbur T, Mathis M, Shankland EG, Trieu A, Harper ME, Marcinek DJ. Impaired adaptability of in vivo mitochondrial energetics to acute oxidative insult in aged skeletal muscle. Mech Ageing Dev 2012; 133:620-8. [PMID: 22935551 DOI: 10.1016/j.mad.2012.08.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Revised: 07/17/2012] [Accepted: 08/04/2012] [Indexed: 12/20/2022]
Abstract
Periods of elevated reactive oxygen species (ROS) production are a normal part of mitochondrial physiology. However, little is known about age-related changes in the mitochondrial response to elevated ROS in vivo. Significantly, ROS-induced uncoupling of oxidative phosphorylation has received attention as a negative feedback mechanism to reduce mitochondrial superoxide production. Here we use a novel in vivo spectroscopy system to test the hypothesis that ROS-induced uncoupling is diminished in aged mitochondria. This system simultaneously acquires (31)P magnetic resonance and near-infrared optical spectra to non-invasively measure phosphometabolite and O(2) concentrations in mouse skeletal muscle. Using low dose paraquat to elevate intracellular ROS we assess in vivo mitochondrial function in young, middle aged, and old mice. Oxidative phosphorylation was uncoupled to the same degree in response to ROS at each age, but this uncoupling was associated with loss of phosphorylation capacity and total ATP in old mice only. Using mice lacking UCP3 we demonstrate that this in vivo uncoupling is independent of this putative uncoupler of skeletal muscle mitochondria. These data indicate that ROS-induced uncoupling persists throughout life, but that oxidative stress leads to mitochondrial deficits and loss of ATP in aged organisms that may contribute to impaired function and degeneration.
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Affiliation(s)
- Michael P Siegel
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA 98195, USA.
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