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Wang M, Wu X, Jiao Y, Yin W, Zhang L. Life-Long Aerobic Exercise is a Non-Pharmacological Approach for Inducing Autophagy and Delaying Muscle Atrophy in the Aging Population. Aging Dis 2024:AD.2024.0318. [PMID: 38607740 DOI: 10.14336/ad.2024.0318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Accepted: 03/18/2024] [Indexed: 04/14/2024] Open
Abstract
Numerous bodily processes deteriorate with age, chief among them being the loss of muscle mass and function. The condition referred to as aging myasthenia gravis impairs older persons' quality of life and is linked to a higher risk of several chronic illnesses. An increasing number of studies conducted in the last several years has demonstrated that moderate exercise can halt this process. Specifically, by promoting autophagy, aerobic exercise helps to postpone the onset of senile myasthenia gravis. In this work, we will explore how aerobic exercise modulates autophagy to prevent muscle aging and examine the most recent findings in this area of study. We discovered that exercise-induced autophagy can effectively balance protein degradation and relieve skeletal muscle atrophy by looking through pertinent literature. Aerobic exercise has a direct impact on autophagy, but it can also delay the onset of senile myasthenia gravis by enhancing blood flow, lowering inflammation, and boosting muscle oxidative capacity. In order to postpone the onset of senile myasthenia gravis, research on the mechanism of action of aerobic exercise in inducing autophagy will be discussed in detail in this study.
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Affiliation(s)
- Mingwei Wang
- School of Physical Education, China University of Mining and Technology, Xuzhou, Jiangsu, China
| | - Xiangzhi Wu
- School of Physical Education, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Yuyao Jiao
- School of Physical Education, Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Wenli Yin
- JSNU SPBPU Institute of Engineering Sino-Russian Institute of Jiangsu Normal University, Xuzhou, Jiangsu, China
| | - Lili Zhang
- JSNU SPBPU Institute of Engineering Sino-Russian Institute of Jiangsu Normal University, Xuzhou, Jiangsu, China
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2
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Botella J, Shaw CS, Bishop DJ. Autophagy and Exercise: Current Insights and Future Research Directions. Int J Sports Med 2024; 45:171-182. [PMID: 37582398 DOI: 10.1055/a-2153-9258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
Autophagy is a cellular process by which proteins and organelles are degraded inside the lysosome. Exercise is known to influence the regulation of autophagy in skeletal muscle. However, as gold standard techniques to assess autophagy flux in vivo are restricted to animal research, important gaps remain in our understanding of how exercise influences autophagy activity in humans. Using available datasets, we show how the gene expression profile of autophagy receptors and ATG8 family members differ between human and mouse skeletal muscle, providing a potential explanation for their differing exercise-induced autophagy responses. Furthermore, we provide a comprehensive view of autophagy regulation following exercise in humans by summarizing human transcriptomic and phosphoproteomic datasets that provide novel targets of potential relevance. These newly identified phosphorylation sites may provide an explanation as to why both endurance and resistance exercise lead to an exercise-induced reduction in LC3B-II, while possibly divergently regulating autophagy receptors, and, potentially, autophagy flux. We also provide recommendations to use ex vivo autophagy flux assays to better understand the influence of exercise, and other stimuli, on autophagy regulation in humans. This review provides a critical overview of the field and directs researchers towards novel research areas that will improve our understanding of autophagy regulation following exercise in humans.
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Affiliation(s)
- Javier Botella
- Metabolic Research Unit, School of Medicine and Institute for Mental and Physical Health and Clinical Translation (IMPACT), Deakin University, Waurn Ponds, Victoria, Australia
| | - Christopher S Shaw
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, Geelong, 3216, VIC, Australia
| | - David J Bishop
- Institute for Health and Sport (iHeS), Victoria University, Melbourne, Australia
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3
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McCormick JJ, McManus MK, King KE, Goulet N, Kenny GP. The intensity-dependent effects of exercise and superimposing environmental heat stress on autophagy in peripheral blood mononuclear cells from older men. Am J Physiol Regul Integr Comp Physiol 2024; 326:R29-R42. [PMID: 37955130 DOI: 10.1152/ajpregu.00163.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/31/2023] [Accepted: 11/01/2023] [Indexed: 11/14/2023]
Abstract
Autophagy is a vital cellular process, essential to maintaining cellular function during acute physiological stressors including exercise and heat stress. We previously showed that autophagy occurs during exercise in an intensity-dependent manner in peripheral blood mononuclear cells (PBMCs) from young men, with elevated responses in the heat. However, given autophagy declines with age, it is unclear whether a similar pattern of response occurs in older adults. Therefore, we evaluated autophagy and the cellular stress response [i.e., apoptosis, inflammation, and the heat shock response (HSR)] in PBMCs from 10 healthy older men [mean (SD): aged 70 yr (5)] in response to 30 min of semirecumbent cycling at low, moderate, and vigorous intensities [40, 55, and 70% maximal oxygen consumption (V̇o2max), respectively] in a temperate (25°C) environment, with an additional vigorous-intensity bout (70% of V̇o2max) performed in a hot environment (40°C). Responses were evaluated before and after exercise, as well as throughout a 6-h seated recovery period performed in the same environmental conditions as the respective exercise bout. Proteins were assessed via Western blot. Although we observed elevations in mean body temperature with each increase in exercise intensity, autophagy was only stimulated during vigorous-intensity exercise, where we observed elevations in LC3-II (P < 0.05). However, when the same exercise was performed in the heat, the LC3-II response was attenuated, which was accompanied by significant p62 accumulation (P < 0.05). Altogether, our findings demonstrate that older adults exhibit autophagic impairments when the same vigorous-intensity exercise is performed in hot environments, potentially underlying heat-induced cellular vulnerability in older men.NEW & NOTEWORTHY We demonstrate that autophagic stimulation occurs in response to short-duration (30-min) vigorous-intensity exercise in peripheral blood mononuclear cells from older adults; however, no changes in autophagy occur during low- or moderate-intensity exercise. Moreover, older adults exhibit autophagic impairments when the same vigorous-intensity exercise is performed in hot ambient conditions. When paired with an attenuated heat shock response, as well as elevated apoptotic responses, older men may exhibit greater cellular vulnerability to exertional heat stress.
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Affiliation(s)
- James J McCormick
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Morgan K McManus
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Kelli E King
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Nicholas Goulet
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Glen P Kenny
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
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4
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Yang K, Hou R, Zhao J, Wang X, Wei J, Pan X, Zhu X. Lifestyle effects on aging and CVD: A spotlight on the nutrient-sensing network. Ageing Res Rev 2023; 92:102121. [PMID: 37944707 DOI: 10.1016/j.arr.2023.102121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 10/12/2023] [Accepted: 11/04/2023] [Indexed: 11/12/2023]
Abstract
Aging is widespread worldwide and a significant risk factor for cardiovascular disease (CVD). Mechanisms underlying aging have attracted considerable attention in recent years. Remarkably, aging and CVD overlap in numerous ways, with deregulated nutrient sensing as a common mechanism and lifestyle as a communal modifier. Interestingly, lifestyle triggers or suppresses multiple nutrient-related signaling pathways. In this review, we first present the composition of the nutrient-sensing network (NSN) and its metabolic impact on aging and CVD. Secondly, we review how risk factors closely associated with CVD, including adverse life states such as sedentary behavior, sleep disorders, high-fat diet, and psychosocial stress, contribute to aging and CVD, with a focus on the bridging role of the NSN. Finally, we focus on the positive effects of beneficial dietary interventions, specifically dietary restriction and the Mediterranean diet, on the regulation of nutrient metabolism and the delayed effects of aging and CVD that depend on the balance of the NSN. In summary, we expound on the interaction between lifestyle, NSN, aging, and CVD.
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Affiliation(s)
- Kaiying Yang
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao 266000, China
| | - Rongyao Hou
- Department of Neurology, The Affiliated Hiser Hospital of Qingdao University, Qingdao 266000, China
| | - Jie Zhao
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao 266000, China
| | - Xia Wang
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao 266000, China
| | - Jin Wei
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao 266000, China
| | - Xudong Pan
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao 266000, China.
| | - Xiaoyan Zhu
- Department of Critical Care Medicine, The Affiliated Hospital of Qingdao University, Qingdao 266000, China.
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5
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Dedert CJ, Bagdady KR, Fisher JS. Prior Treatment with AICAR Causes the Selective Phosphorylation of mTOR Substrates in C2C12 Cells. Curr Issues Mol Biol 2023; 45:8040-8052. [PMID: 37886951 PMCID: PMC10605383 DOI: 10.3390/cimb45100508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 09/05/2023] [Accepted: 09/27/2023] [Indexed: 10/28/2023] Open
Abstract
Metabolic stress in skeletal muscle cells causes sustained metabolic changes, but the mechanisms of the prolonged effects are not fully known. In this study, we tested C2C12 cells with the AMP-activated protein kinase (AMPK) stimulator AICAR and measured the changes in the metabolic pathways and signaling kinases. AICAR caused an acute increase in the phosphorylation of the AMPK target ULK1, the mTORC1 substrate S6K, and the mTORC2 target Akt. Intriguingly, prior exposure to AICAR only decreased glucose-6 phosphate dehydrogenase activity when it underwent three-hour recovery after exposure to AICAR in a bicarbonate buffer containing glucose (KHB) instead of Dulbecco's Minimum Essential Medium (DMEM). The phosphorylation of the mTORC1 target S6K was increased after recovery in DMEM but not KHB, although this appeared to be specific to S6K, as the phosphorylation of the mTORC1 target site on ULK1 was not altered when the cells recovered in DMEM. The phosphorylation of mTORC2 target sites was also heterogenous under these conditions, with Akt increasing at serine 473 while other targets (SGK1 and PKCα) were unaffected. The exposure of cells to rapamycin (an mTORC1 inhibitor) and PP242 (an inhibitor of both mTOR complexes) revealed the differential phosphorylation of mTORC2 substrates. Taken together, the data suggest that prior exposure to AICAR causes the selective phosphorylation of mTOR substrates, even after prolonged recovery in a nutrient-replete medium.
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Goenawan H, Kiasati S, Sylviana N, Megantara I, Lesmana R. Exercise-Induced Autophagy Ameliorates Motor Symptoms Progressivity in Parkinson's Disease Through Alpha-Synuclein Degradation: A Review. Neuropsychiatr Dis Treat 2023; 19:1253-1262. [PMID: 37255530 PMCID: PMC10226548 DOI: 10.2147/ndt.s401416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 04/20/2023] [Indexed: 06/01/2023] Open
Abstract
This study reviews the molecular mechanism of exercise-induced autophagy/mitophagy and its possible mechanism in delaying motor symptoms progressivity in Parkinson's disease (PD). Relevant articles obtained from PubMed and EBSCOhost were reviewed. After analyzing the articles, it was found that autophagy can be induced by exercise and can possibly be activated through the AMPK-ULK1 pathway. Mitophagy can also be induced by exercise and can possibly be activated through PINK1/Parkin pathway and AMPK-dependent pathway. Moreover, exercise-induced autophagy can decrease the accumulation of toxic α-synuclein aggregates in PD and therefore can delay motor symptoms progressivity.
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Affiliation(s)
- Hanna Goenawan
- Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia
| | - Shabrina Kiasati
- Undergraduate Program, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia
| | - Nova Sylviana
- Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia
| | - Imam Megantara
- Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia
| | - Ronny Lesmana
- Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia
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7
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Wang Y, Li J, Zhang Z, Wang R, Bo H, Zhang Y. Exercise Improves the Coordination of the Mitochondrial Unfolded Protein Response and Mitophagy in Aging Skeletal Muscle. Life (Basel) 2023; 13:life13041006. [PMID: 37109535 PMCID: PMC10142204 DOI: 10.3390/life13041006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 04/09/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
The mitochondrial unfolded protein response (UPRmt) and mitophagy are two mitochondrial quality control (MQC) systems that work at the molecular and organelle levels, respectively, to maintain mitochondrial homeostasis. Under stress conditions, these two processes are simultaneously activated and compensate for each other when one process is insufficient, indicating mechanistic coordination between the UPRmt and mitophagy that is likely controlled by common upstream signals. This review focuses on the molecular signals regulating this coordination and presents evidence showing that this coordination mechanism is impaired during aging and promoted by exercise. Furthermore, the bidirectional regulation of reactive oxygen species (ROS) and AMPK in modulating this mechanism is discussed. The hierarchical surveillance network of MQC can be targeted by exercise-derived ROS to attenuate aging, which offers a molecular basis for potential therapeutic interventions for sarcopenia.
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Affiliation(s)
- Yan Wang
- Tianjin Key Laboratory of Exercise Physiology and Sports Medicine, School of Exercise and Health, Tianjin University of Sport, Tianjin 301617, China
- School of Physical Education, Guangdong Institute of Petrochemical Technology, Maoming 525000, China
| | - Jialin Li
- Tianjin Key Laboratory of Exercise Physiology and Sports Medicine, School of Exercise and Health, Tianjin University of Sport, Tianjin 301617, China
| | - Ziyi Zhang
- Tianjin Key Laboratory of Exercise Physiology and Sports Medicine, School of Exercise and Health, Tianjin University of Sport, Tianjin 301617, China
| | - Runzi Wang
- Tianjin Key Laboratory of Exercise Physiology and Sports Medicine, School of Exercise and Health, Tianjin University of Sport, Tianjin 301617, China
| | - Hai Bo
- Tianjin Key Laboratory of Exercise Physiology and Sports Medicine, School of Exercise and Health, Tianjin University of Sport, Tianjin 301617, China
- Department of Military Training Medicines, Logistics University of Chinese People's Armed Police Force, Tianjin 300162, China
| | - Yong Zhang
- Tianjin Key Laboratory of Exercise Physiology and Sports Medicine, School of Exercise and Health, Tianjin University of Sport, Tianjin 301617, China
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8
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Turknett J, Wood TR. Demand Coupling Drives Neurodegeneration: A Model of Age-Related Cognitive Decline and Dementia. Cells 2022; 11:2789. [PMID: 36139364 PMCID: PMC9496827 DOI: 10.3390/cells11182789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/27/2022] [Accepted: 09/05/2022] [Indexed: 12/12/2022] Open
Abstract
The societal burden of Alzheimer's Disease (AD) and other major forms of dementia continues to grow, and multiple pharmacological agents directed towards modifying the pathological "hallmarks" of AD have yielded disappointing results. Though efforts continue towards broadening and deepening our knowledge and understanding of the mechanistic and neuropathological underpinnings of AD, our previous failures motivate a re-examination of how we conceptualize AD pathology and progression. In addition to not yielding effective treatments, the phenotypically heterogeneous biological processes that have been the primary area of focus to date have not been adequately shown to be necessary or sufficient to explain the risk and progression of AD. On the other hand, a growing body of evidence indicates that lifestyle and environment represent the ultimate level of causation for AD and age-related cognitive decline. Specifically, the decline in cognitive demands over the lifespan plays a central role in driving the structural and functional deteriorations of the brain. In the absence of adequate cognitive stimulus, physiological demand-function coupling leads to downregulation of growth, repair, and homeostatic processes, resulting in deteriorating brain tissue health, function, and capacity. In this setting, the heterogeneity of associated neuropathological tissue hallmarks then occurs as a consequence of an individual's genetic and environmental background and are best considered downstream markers of the disease process rather than specific targets for direct intervention. In this manuscript we outline the evidence for a demand-driven model of age-related cognitive decline and dementia and why it mandates a holistic approach to dementia treatment and prevention that incorporates the primary upstream role of cognitive demand.
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Affiliation(s)
- Josh Turknett
- Brainjo Center for Neurology and Cognitive Enhancement, Atlanta, GA 30076, USA
| | - Thomas R. Wood
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
- Institute for Human and Machine Cognition, Pensacola, FL 32502, USA
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9
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McCormick JJ, Côté MD, King KE, McManus MK, Goulet N, Dokladny K, Moseley PL, Kenny GP. The autophagic response to exercise in peripheral blood mononuclear cells from young men is intensity-dependent and is altered by exposure to environmental heat. Am J Physiol Regul Integr Comp Physiol 2022; 323:R467-R482. [PMID: 35993558 DOI: 10.1152/ajpregu.00110.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Autophagy is essential to maintaining cellular homeostasis in all eukaryotic cells and to tolerance of acute stressors such as starvation, heat, and recovery following exercise. Limited information exists regarding the exercise intensity-dependent autophagic response in humans, and it is unknown how environmental heat stress may modulate this response. Therefore, we evaluated autophagy and accompanying pathways of cellular stress (the heat shock response [HSR], apoptosis, and acute inflammation) in peripheral blood mononuclear cells (PBMCs) from 10 young men (mean [SD]; 22 [2] years) before, immediately after and up to 6h post-exercise recovery from 30 minutes of low-, moderate-, and high-intensity semi-recumbent cycling (40, 55 and 70% of maximal oxygen consumption (VO2max), respectively)in a temperate environment (25°C) and at 70% of VO2max in a hot environment (40°C). Changes in protein content were analyzed via Western blot. Each increase in exercise intensity was associated with elevations in mean body temperature. LC3-II increased following moderate-intensity exercise, with further increases following high-intensity exercise (p < 0.05). However, an increase in beclin-2 and ULK1, with a decrease in p62 was only observed after high-intensity exercise, which was paralleled by elevated TNF-α and cleaved-caspase-3, with the HSR peaking at 6h after exercise (p < 0.05). When exercise was performed in the heat, greater LC3-II and cleaved-caspase-3 accumulation was observed, however beclin-2 declined in recovery (p < 0.05). Therefore, our findings indicate that autophagy in PBMCs during exercise may be associated with greater heat strain exhibited during increasing exercise intensities, which is modulated by exposure to heat.
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Affiliation(s)
- James J McCormick
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Melissa D Côté
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Kelli E King
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Morgan K McManus
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Nicholas Goulet
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Karol Dokladny
- Department of Internal Medicine, University of New Mexico, Albuquerque, NM, United States
| | - Pope L Moseley
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,College of Health Solutions, Arizona State University, Phoenix, Arizona, United States
| | - Glen P Kenny
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada.,Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
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10
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Peñailillo L, Valladares-Ide D, Jannas-Velas S, Flores-Opazo M, Jalón M, Mendoza L, Nuñez I, Diaz-Patiño O. Effects of eccentric, concentric and eccentric/concentric training on muscle function and mass, functional performance, cardiometabolic health, quality of life and molecular adaptations of skeletal muscle in COPD patients: a multicentre randomised trial. BMC Pulm Med 2022; 22:278. [PMID: 35854255 PMCID: PMC9297587 DOI: 10.1186/s12890-022-02061-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 07/04/2022] [Indexed: 11/12/2022] Open
Abstract
Background Chronic obstructive pulmonary disease (COPD) is the third cause of death worldwide. COPD is characterised by dyspnoea, limited exercise tolerance, and muscle dysfunction. Muscle dysfunction has been linked to dysregulation between muscle protein synthesis, myogenesis and degradation mechanisms. Conventional concentric cycling has been shown to improve several clinical outcomes and reduce muscle wasting in COPD patients. Eccentric cycling is a less explored exercise modality that allows higher training workloads imposing lower cardio-metabolic demand during exercise, which has shown to induce greater muscle mass and strength gains after training. Interestingly, the combination of eccentric and concentric cycling training has scarcely been explored. The molecular adaptations of skeletal muscle after exercise interventions in COPD have shown equivocal results. The mechanisms of muscle wasting in COPD and whether it can be reversed by exercise training are unclear. Therefore, this study aims two-fold: (1) to compare the effects of 12 weeks of eccentric (ECC), concentric (CONC), and combined eccentric/concentric (ECC/CONC) cycling training on muscle mass and function, cardiometabolic health, physical activity levels and quality of life in severe COPD patients; and (2) to examine the molecular adaptations regulating muscle growth after training, and whether they occur similarly in specific muscle fibres (i.e., I, IIa and IIx). Methods Study 1 will compare the effects of 12 weeks of CONC, ECC, versus ECC/CONC training on muscle mass and function, cardiometabolic health, levels of physical activity and quality of life of severe COPD patients using a multicentre randomised trial. Study 2 will investigate the effects of these training modalities on the molecular adaptations regulating muscle protein synthesis, myogenesis and muscle degradation in a subgroup of patients from Study 1. Changes in muscle fibres morphology, protein content, genes, and microRNA expression involved in skeletal muscle growth will be analysed in specific fibre-type pools. Discussion We aim to demonstrate that a combination of eccentric and concentric exercise could maximise the improvements in clinical outcomes and may be ideal for COPD patients. We also expect to unravel the molecular mechanisms underpinning muscle mass regulation after training in severe COPD patients. Trial Registry: Deutshches Register Klinischer Studien; Trial registration: DRKS00027331; Date of registration: 12 January 2022. https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00027331.
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Affiliation(s)
- Luis Peñailillo
- Exercise and Rehabilitation Sciences Laboratory, School of Physical Therapy, Faculty of Rehabilitation Sciences, Universidad Andres Bello, 700 Fernández Concha, Las Condes, 7591538, Santiago, Chile.
| | - Denisse Valladares-Ide
- Long Active Life Laboratory, Instituto de Ciencias de la Salud, Universidad de O'Higgins, Rancagua, Chile
| | - Sebastián Jannas-Velas
- Long Active Life Laboratory, Instituto de Ciencias de la Salud, Universidad de O'Higgins, Rancagua, Chile
| | | | | | - Laura Mendoza
- Respiratory Unit, Departamento de Medicina, Hospital Clínico Universidad de Chile, Santiago, Chile
| | - Ingrid Nuñez
- Department of Pulmonary Diseases, Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile.,Department of Critical Care, Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile
| | - Orlando Diaz-Patiño
- Department of Pulmonary Diseases, Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile.,Department of Critical Care, Faculty of Medicine, Pontifical Catholic University of Chile, Santiago, Chile
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11
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Marshall RN, Smeuninx B, Seabright AP, Morgan PT, Atherton PJ, Philp A, Breen L. No effect of five days of bed rest or short-term resistance exercise prehabilitation on markers of skeletal muscle mitochondrial content and dynamics in older adults. Physiol Rep 2022; 10:e15345. [PMID: 35785448 PMCID: PMC9251856 DOI: 10.14814/phy2.15345] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 05/12/2022] [Accepted: 05/16/2022] [Indexed: 11/24/2022] Open
Abstract
Bed rest (BR) results in significant impairments in skeletal muscle metabolism. Mitochondrial metabolism is reportedly highly sensitive to disuse, with dysregulated fission-fusion events and impaired oxidative function previously reported. The effects of clinically relevant short-term BR (≤5 days) on mitochondrial protein expression are presently unclear, as are the effects of exercise prehabilitation as a potential counteractive intervention. The present study examined the effects of a 5-day period of BR and short-term resistance exercise prehabilitation (ST-REP) on mitochondrial-protein content. Ten older men (71 ± 4 years) underwent 5 days of BR, completing four sessions of high-volume unilateral resistance exercise prehabilitation over 7 days beforehand. Muscle biopsies were obtained from the vastus lateralis in the non-exercised control and exercised legs, both pre- and post-prehabilitation and pre- and post-BR, to determine changes in citrate synthase enzyme activity and the expression of key proteins in the mitochondrial electron transport chain and molecular regulators of fission-fusion dynamics, biosynthesis, and mitophagy. We observed no significant effect of either BR or ST-REP on citrate synthase protein content, enzyme activity, or ETC complex I-V protein content. Moreover, we observed no significant changes in markers of mitochondrial fission and fusion (p-DRP1S616 , p-DRP1S637 , p-DRP1S616/S637 ratio, p-MFFS146 , Mitofillin, OPA1, or MFN2 (p > 0.05 for all). Finally, we observed no differences in markers of biosynthesis (p-AMPKT172 , p-ACCS79 , PGC1a, TFAM) or mitophagy-related signaling (ULK-1, BNIP3/NIX, LC3B I/II) (p > 0.05 for all). In contrast to previous longer-term periods of musculoskeletal disuse (i.e., 7-14 days), a clinically relevant, 5-day period of BR resulted in no significant perturbation in muscle mitochondrial protein signaling in healthy older adults, with no effect of ST-REP in the week prior to BR. Accordingly, disuse-induced muscle atrophy may precede alterations in mitochondrial content.
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Affiliation(s)
- Ryan N Marshall
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, Birmingham, United Kingdom
| | - Benoit Smeuninx
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Alex P Seabright
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Paul T Morgan
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, Birmingham, United Kingdom
| | - Philip J Atherton
- Division of Medical sciences and Graduate Entry Medicine, Royal Derby Hospital, Derby, United Kingdom.,Clinical, Metabolic and Molecular Physiology, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
| | - Andrew Philp
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,Mitochondrial Metabolism and Ageing Laboratory, Garvan Institute of Medical Research, Sydney, New South Wales, Australia.,St Vincent's Clinical School, UNSW Medicine, UNSW Sydney, Sydney, New South Wales, Australia
| | - Leigh Breen
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, Birmingham, United Kingdom.,NIHR Biomedical Research Centre, Birmingham, United Kingdom
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12
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Ribarič S. Physical Exercise, a Potential Non-Pharmacological Intervention for Attenuating Neuroinflammation and Cognitive Decline in Alzheimer's Disease Patients. Int J Mol Sci 2022; 23:ijms23063245. [PMID: 35328666 PMCID: PMC8952567 DOI: 10.3390/ijms23063245] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 12/14/2022] Open
Abstract
This narrative review summarises the evidence for considering physical exercise (PE) as a non-pharmacological intervention for delaying cognitive decline in patients with Alzheimer’s disease (AD) not only by improving cardiovascular fitness but also by attenuating neuroinflammation. Ageing is the most important risk factor for AD. A hallmark of the ageing process is a systemic low-grade chronic inflammation that also contributes to neuroinflammation. Neuroinflammation is associated with AD, Parkinson’s disease, late-onset epilepsy, amyotrophic lateral sclerosis and anxiety disorders. Pharmacological treatment of AD is currently limited to mitigating the symptoms and attenuating progression of the disease. AD animal model studies and human studies on patients with a clinical diagnosis of different stages of AD have concluded that PE attenuates cognitive decline not only by improving cardiovascular fitness but possibly also by attenuating neuroinflammation. Therefore, low-grade chronic inflammation and neuroinflammation should be considered potential modifiable risk factors for AD that can be attenuated by PE. This opens the possibility for personalised attenuation of neuroinflammation that could also have important health benefits for patients with other inflammation associated brain disorders (i.e., Parkinson’s disease, late-onset epilepsy, amyotrophic lateral sclerosis and anxiety disorders). In summary, life-long, regular, structured PE should be considered as a supplemental intervention for attenuating the progression of AD in human. Further studies in human are necessary to develop optimal, personalised protocols, adapted to the progression of AD and the individual’s mental and physical limitations, to take full advantage of the beneficial effects of PE that include improved cardiovascular fitness, attenuated systemic inflammation and neuroinflammation, stimulated brain Aβ peptides brain catabolism and brain clearance.
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Affiliation(s)
- Samo Ribarič
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, SI-1000 Ljubljana, Slovenia
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13
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Exercise and Training Regulation of Autophagy Markers in Human and Rat Skeletal Muscle. Int J Mol Sci 2022; 23:ijms23052619. [PMID: 35269762 PMCID: PMC8910616 DOI: 10.3390/ijms23052619] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 02/20/2022] [Accepted: 02/25/2022] [Indexed: 02/05/2023] Open
Abstract
Autophagy is a key intracellular mechanism by which cells degrade old or dysfunctional proteins and organelles. In skeletal muscle, evidence suggests that exercise increases autophagosome content and autophagy flux. However, the exercise-induced response seems to differ between rodents and humans, and little is known about how different exercise prescription parameters may affect these results. The present study utilised skeletal muscle samples obtained from four different experimental studies using rats and humans. Here, we show that, following exercise, in the soleus muscle of Wistar rats, there is an increase in LC3B-I protein levels immediately after exercise (+109%), and a subsequent increase in LC3B-II protein levels 3 h into the recovery (+97%), despite no change in Map1lc3b mRNA levels. Conversely, in human skeletal muscle, there is an immediate exercise-induced decrease in LC3B-II protein levels (−24%), independent of whether exercise is performed below or above the maximal lactate steady state, which returns to baseline 3.5 h following recovery, while no change in LC3B-I protein levels or MAP1LC3B mRNA levels is observed. SQSTM1/p62 protein and mRNA levels did not change in either rats or humans following exercise. By employing an ex vivo autophagy flux assay previously used in rodents we demonstrate that the exercise-induced decrease in LC3B-II protein levels in humans does not reflect a decreased autophagy flux. Instead, effect size analyses suggest a modest-to-large increase in autophagy flux following exercise that lasts up to 24 h. Our findings suggest that exercise-induced changes in autophagosome content markers differ between rodents and humans, and that exercise-induced decreases in LC3B-II protein levels do not reflect autophagy flux level.
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14
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So B, Park J, Jang J, Lim W, Imdad S, Kang C. Effect of Aerobic Exercise on Oxidative Stress and Inflammatory Response During Particulate Matter Exposure in Mouse Lungs. Front Physiol 2022; 12:773539. [PMID: 35185596 PMCID: PMC8850364 DOI: 10.3389/fphys.2021.773539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 12/03/2021] [Indexed: 11/22/2022] Open
Abstract
Regular exercise provides several health benefits that can improve the cardiovascular and musculoskeletal systems, but clear evidence on the effect of exercise-induced hyperventilation in particulate matter (PM) exposure is still lacking. This study aimed to investigate the effects of exercise in PM exposure on reactive oxygen species (ROS) generation, inflammatory response, and mitochondrial integrity in human lung epithelial cells (A549), as well as in mouse lung tissue. In in vitro experiments, PM treatment was shown to significantly increased ROS production, and reduced cell viability and mitochondrial function in A549 cells. The mice were divided into four groups for an in vivo exercise experiment: control (CON), PM inhalation (PI), PM inhalation during exercise (PIE), and exercise (EX) groups. The PI and PIE groups were exposed to 100 μg/m3 of PM for 1 h per day for a week. The PIE and EX groups performed treadmill exercises every day for 1 h at 20 m/min for a week. The levels of pro-inflammatory markers (IL-6 and TNF-α) were significantly higher in the PI group than in the CON group (P < 0.001 and P < 0.01, respectively). The carbonyl protein level was decreased in EX vs. PI (P < 0.001). Mitochondrial fission (Drp1) content was significantly decreased in the EX vs. CON group (P < 0.01), but anti-mitochondrial fission (P-Drp1 Ser637) was increased in the EX vs. PI group (P < 0.05). Mitochondrial autophagy (mitophagy), which is an assessment of mitochondrial integrity, was markedly increased in PI vs. CON (P < 0.001), but the level was reversed in PIE (P < 0.05). Lung fibrosis was increased in PI vs. CON group (P < 0.001), however, the cells were rescued in the PIE (P < 0.001). The number of apoptotic cells was remarkably increased in the PI vs. CON group (P < 0.001), whereas the level was decreased in the PIE (P < 0.001). Taken together, these results showed that short-term exposure to PM triggers oxidative stress, pro-inflammatory responses, and apoptosis in the lungs, but the PM-induced adverse effects on the lung tissue are not exacerbated by exercise-induced PM hyperventilation but rather has a protective effect.
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Affiliation(s)
- Byunghun So
- Molecular Metabolism in Health and Disease, Exercise Physiology Laboratory, Inha University, Incheon, South Korea
| | - Jinhan Park
- Molecular Metabolism in Health and Disease, Exercise Physiology Laboratory, Inha University, Incheon, South Korea
| | - Junho Jang
- Molecular Metabolism in Health and Disease, Exercise Physiology Laboratory, Inha University, Incheon, South Korea
| | - Wonchung Lim
- Department of Sports Medicine, College of Health Science, Cheongju University, Cheongju, South Korea
| | - Saba Imdad
- Molecular Metabolism in Health and Disease, Exercise Physiology Laboratory, Inha University, Incheon, South Korea
- Department of Biomedical Laboratory Science, College of Health Science, Cheongju University, Cheongju, South Korea
| | - Chounghun Kang
- Molecular Metabolism in Health and Disease, Exercise Physiology Laboratory, Inha University, Incheon, South Korea
- Department of Physical Education, College of Education, Inha University, Incheon, South Korea
- *Correspondence: Chounghun Kang,
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15
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Cardinale DA, Gejl KD, Petersen KG, Nielsen J, Ørtenblad N, Larsen FJ. Short-term intensified training temporarily impairs mitochondrial respiratory capacity in elite endurance athletes. J Appl Physiol (1985) 2021; 131:388-400. [PMID: 34110230 DOI: 10.1152/japplphysiol.00829.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The maintenance of healthy and functional mitochondria is the result of a complex mitochondrial turnover and herein quality-control program that includes both mitochondrial biogenesis and autophagy of mitochondria. The aim of this study was to examine the effect of an intensified training load on skeletal muscle mitochondrial quality control in relation to changes in mitochondrial oxidative capacity, maximal oxygen consumption, and performance in highly trained endurance athletes. Elite endurance athletes (n = 27) performed high-intensity interval exercise followed by moderate-intensity continuous exercise 3 days per week for 4 wk in addition to their usual volume of training. Mitochondrial oxidative capacity, abundance of mitochondrial proteins, markers of autophagy, and antioxidant capacity of skeletal muscle were assessed in skeletal muscle biopsies before and after the intensified training period. The intensified training period increased several autophagy markers suggesting an increased turnover of mitochondrial and cytosolic proteins. In permeabilized muscle fibers, mitochondrial respiration was ∼20% lower after training although some markers of mitochondrial density increased by 5%-50%, indicative of a reduced mitochondrial quality by the intensified training intervention. The antioxidative proteins UCP3, ANT1, and SOD2 were increased after training, whereas we found an inactivation of aconitase. In agreement with the lower aconitase activity, the amount of mitochondrial LON protease that selectively degrades oxidized aconitase was doubled. Together, this suggests that mitochondrial respiratory function is impaired during the initial recovery from a period of intensified endurance training whereas mitochondrial quality control is slightly activated in highly trained skeletal muscle.NEW & NOTEWORTHY We show that mitochondrial respiration is temporarily impaired after a period of intensified exercise training in elite athletes. In parallel, proteins involved in the antioxidative response including SOD2, UCP3, and ANT2 were upregulated, whereas mitochondrial biogenesis was slightly activated. Despite the mitochondrial respiratory impairments, physical performance was improved a few days after the intense training period.
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Affiliation(s)
- Daniele A Cardinale
- Åstrand Laboratory, Department of Physiology, Nutrition, and Biomechanics, The Swedish School of Sport and Health Sciences (GIH), Stockholm, Sweden.,Elite Performance Centre, Bosön-Swedish Sports Confederation, Lidingö, Sweden
| | - Kasper D Gejl
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Kristine G Petersen
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Joachim Nielsen
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Niels Ørtenblad
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Filip J Larsen
- Åstrand Laboratory, Department of Physiology, Nutrition, and Biomechanics, The Swedish School of Sport and Health Sciences (GIH), Stockholm, Sweden
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16
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Williamson E, Moore DR. A Muscle-Centric Perspective on Intermittent Fasting: A Suboptimal Dietary Strategy for Supporting Muscle Protein Remodeling and Muscle Mass? Front Nutr 2021; 8:640621. [PMID: 34179054 PMCID: PMC8219935 DOI: 10.3389/fnut.2021.640621] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 05/19/2021] [Indexed: 01/04/2023] Open
Abstract
Muscle protein is constantly “turning over” through the breakdown of old/damaged proteins and the resynthesis of new functional proteins, the algebraic difference determining net muscle gain, maintenance, or loss. This turnover, which is sensitive to the nutritional environment, ultimately determines the mass, quality, and health of skeletal muscle over time. Intermittent fasting has become a topic of interest in the health community as an avenue to improve health and body composition primarily via caloric deficiency as well as enhanced lipolysis and fat oxidation secondary to attenuated daily insulin response. However, this approach belies the established anti-catabolic effect of insulin on skeletal muscle. More importantly, muscle protein synthesis, which is the primary regulated turnover variable in healthy humans, is stimulated by the consumption of dietary amino acids, a process that is saturated at a moderate protein intake. While limited research has explored the effect of intermittent fasting on muscle-related outcomes, we propose that infrequent meal feeding and periods of prolonged fasting characteristic of models of intermittent fasting may be counter-productive to optimizing muscle protein turnover and net muscle protein balance. The present commentary will discuss the regulation of muscle protein turnover across fasted and fed cycles and contrast it with studies exploring how dietary manipulation alters the partitioning of fat and lean body mass. It is our position that intermittent fasting likely represents a suboptimal dietary approach to remodel skeletal muscle, which could impact the ability to maintain or enhance muscle mass and quality, especially during periods of reduced energy availability.
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Affiliation(s)
- Eric Williamson
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Daniel R Moore
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
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17
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Chua JP, De Calbiac H, Kabashi E, Barmada SJ. Autophagy and ALS: mechanistic insights and therapeutic implications. Autophagy 2021; 18:254-282. [PMID: 34057020 PMCID: PMC8942428 DOI: 10.1080/15548627.2021.1926656] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Mechanisms of protein homeostasis are crucial for overseeing the clearance of misfolded and toxic proteins over the lifetime of an organism, thereby ensuring the health of neurons and other cells of the central nervous system. The highly conserved pathway of autophagy is particularly necessary for preventing and counteracting pathogenic insults that may lead to neurodegeneration. In line with this, mutations in genes that encode essential autophagy factors result in impaired autophagy and lead to neurodegenerative conditions such as amyotrophic lateral sclerosis (ALS). However, the mechanistic details underlying the neuroprotective role of autophagy, neuronal resistance to autophagy induction, and the neuron-specific effects of autophagy-impairing mutations remain incompletely defined. Further, the manner and extent to which non-cell autonomous effects of autophagy dysfunction contribute to ALS pathogenesis are not fully understood. Here, we review the current understanding of the interplay between autophagy and ALS pathogenesis by providing an overview of critical steps in the autophagy pathway, with special focus on pivotal factors impaired by ALS-causing mutations, their physiologic effects on autophagy in disease models, and the cell type-specific mechanisms regulating autophagy in non-neuronal cells which, when impaired, can contribute to neurodegeneration. This review thereby provides a framework not only to guide further investigations of neuronal autophagy but also to refine therapeutic strategies for ALS and related neurodegenerative diseases.Abbreviations: ALS: amyotrophic lateral sclerosis; Atg: autophagy-related; CHMP2B: charged multivesicular body protein 2B; DPR: dipeptide repeat; FTD: frontotemporal dementia; iPSC: induced pluripotent stem cell; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; PINK1: PTEN induced kinase 1; RNP: ribonuclear protein; sALS: sporadic ALS; SPHK1: sphingosine kinase 1; TARDBP/TDP-43: TAR DNA binding protein; TBK1: TANK-binding kinase 1; TFEB: transcription factor EB; ULK: unc-51 like autophagy activating kinase; UPR: unfolded protein response; UPS: ubiquitin-proteasome system; VCP: valosin containing protein.
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Affiliation(s)
- Jason P Chua
- Department of Neurology, University of Michigan, Ann Arbor, MI, United States
| | - Hortense De Calbiac
- Recherche translationnelle sur les maladies neurologiques, Institut Imagine, UMR-1163 INSERM et Université Paris Descartes, Hôpital Universitaire Necker-Enfants Malades, Paris, France
| | - Edor Kabashi
- Recherche translationnelle sur les maladies neurologiques, Institut Imagine, UMR-1163 INSERM et Université Paris Descartes, Hôpital Universitaire Necker-Enfants Malades, Paris, France
| | - Sami J Barmada
- Department of Neurology, University of Michigan, Ann Arbor, MI, United States
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18
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Sebastián D, Zorzano A. Self-Eating for Muscle Fitness: Autophagy in the Control of Energy Metabolism. Dev Cell 2021; 54:268-281. [PMID: 32693059 DOI: 10.1016/j.devcel.2020.06.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 05/27/2020] [Accepted: 06/26/2020] [Indexed: 01/09/2023]
Abstract
Cellular processes that sense and transmit metabolic changes are crucial for adaptation to external signals. In this regard, autophagy provides energy upon nutrient deprivation and represents a quality control mechanism that eliminates damaged organelles or proteins. Here, we review recent findings on the metabolic pathways controlling autophagy in skeletal muscle, a plastic tissue that undergoes major changes in energy demands. We also analyze the implications of autophagy in the regulation of energy metabolism in muscle and how alterations in this process affect energy homeostasis at the whole-body level and the development of metabolic diseases and aging.
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Affiliation(s)
- David Sebastián
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain; Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain.
| | - Antonio Zorzano
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain; Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain.
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19
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Høgild ML, Gudiksen A, Pilegaard H, Stødkilde-Jørgensen H, Pedersen SB, Møller N, Jørgensen JOL, Jessen N. Redundancy in regulation of lipid accumulation in skeletal muscle during prolonged fasting in obese men. Physiol Rep 2020; 7:e14285. [PMID: 31724339 PMCID: PMC6854099 DOI: 10.14814/phy2.14285] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Fasting in human subjects shifts skeletal muscle metabolism toward lipid utilization and accumulation, including intramyocellular lipid (IMCL) deposition. Growth hormone (GH) secretion amplifies during fasting and promotes lipolysis and lipid oxidation, but it is unknown to which degree lipid deposition and metabolism in skeletal muscle during fasting depends on GH action. To test this, we studied nine obese but otherwise healthy men thrice: (a) in the postabsorptive state (“CTRL”), (b) during 72‐hr fasting (“FAST”), and (c) during 72‐hr fasting and treatment with a GH antagonist (GHA) (“FAST + GHA”). IMCL was assessed by magnetic resonance spectroscopy (MRS) and blood samples were drawn for plasma metabolomics assessment while muscle biopsies were obtained for measurements of regulators of substrate metabolism. Prolonged fasting was associated with elevated GH levels and a pronounced GHA‐independent increase in circulating medium‐ and long‐chain fatty acids, glycerol, and ketone bodies indicating increased supply of lipid intermediates to skeletal muscle. Additionally, fasting was associated with a release of short‐, medium‐, and long‐chain acylcarnitines to the circulation from an increased β‐oxidation. This was consistent with a ≈55%–60% decrease in pyruvate dehydrogenase (PDHa) activity. Opposite, IMCL content increased ≈75% with prolonged fasting without an effect of GHA. We suggest that prolonged fasting increases lipid uptake in skeletal muscle and saturates lipid oxidation, both favoring IMCL deposition. This occurs without a detectable effect of GHA on skeletal muscle lipid metabolism.
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Affiliation(s)
- Morten L Høgild
- Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Anders Gudiksen
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | | | - Hans Stødkilde-Jørgensen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,The MR Research Center, Aarhus University Hospital, Copenhagen, Denmark
| | - Steen Bønløkke Pedersen
- Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Niels Møller
- Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Jens O L Jørgensen
- Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Niels Jessen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Clinical Pharmacology, Aarhus University Hospital, Aarhus, Denmark.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
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20
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Herrenbruck AR, Bollinger LM. Role of skeletal muscle autophagy in high-fat-diet-induced obesity and exercise. Nutr Rev 2020; 78:56-64. [PMID: 31529063 DOI: 10.1093/nutrit/nuz044] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Autophagy is a complex degradation pathway responsible for clearing damaged and dysfunctional organelles. High-fat-diet-induced obesity has been shown to alter autophagy throughout the body in a tissue-specific manner. The impact of obesity on skeletal muscle autophagy has yet to be elucidated. This review examines the impact of high-fat-diet-induced obesity and exercise on skeletal muscle autophagy. Better understanding this major quality control mechanism may help develop novel therapies to combat high-fat-diet-induced obesity comorbidities.
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Affiliation(s)
- Adrienne R Herrenbruck
- A.R. Herrenbruck, and L.M. Bollinger are with the Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, Kentucky, USA
| | - Lance M Bollinger
- A.R. Herrenbruck, and L.M. Bollinger are with the Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, Kentucky, USA
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21
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Ran D, Ma Y, Liu W, Luo T, Zheng J, Wang D, Song R, Zhao H, Zou H, Gu J, Yuan Y, Bian J, Liu Z. TGF-β-activated kinase 1 (TAK1) mediates cadmium-induced autophagy in osteoblasts via the AMPK / mTORC1 / ULK1 pathway. Toxicology 2020; 442:152538. [PMID: 32693121 DOI: 10.1016/j.tox.2020.152538] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 06/23/2020] [Accepted: 07/13/2020] [Indexed: 01/28/2023]
Abstract
Cadmium (Cd) is one of worldwide environmental pollutants that causes bone homeostasis, which depends on the resorption of bones by osteoclasts and formation of bones by the osteoblasts (OB). However, the Cd toxicity on OB and its mechanism are unclear. Autophagy is an evolutionarily conserved degradation process in which domestic intracellular components are selectively digested for the recycling of nutrients and energy. This process is indispensable for cell homeostasis maintenance and stress responses. Dysregulation at the level of autophagic activity consequently disturbs the balance between bone formation and bone resorption and mediates the onset and progression of multiple bone diseases, including osteoporosis. TAK1 has been recently emerged as an activator of AMPK and hence an autophagy inducer. AMPK is a key molecule that induces autophagy and regulates cellular metabolism to maintain energy homeostasis. Conversely, autophagy is inhibited by mTORC1. In this study, we found that Cd treatment caused the formation of autophagosomes, LC3-II lipidation and p62 downregulation, and the increased autophagic flux, indicating that Cd treatment induced autophagy in OBs. Cd treatment induced TAK1 activation mediated AMPK phosphorylation, which promoted autophagy via phosphorylation of ULK1 at S317. Meanwhile, Cd treatment dramatically decreased mTORC1, S6K1, 4E-BP1, S6, ULK1S555 and ULK1S757 phosphorylation, suggesting that mTORC1 activity was inhibited and inactive mTORC1 prevents ULK1 activation by phosphorylating ULK1 at SerS555 and Ser757. Our data strongly suggest that TAK1 mediates AMPK activation, which activates ULK1 by phosphorylating ULK1S317 and suppressing mTORC1-mediated ULK1S555 and ULK1S757 phosphorylation. Our study has revealed a signaling mechanism for TAK1 in Cd-induced autophagy in OBs.
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Affiliation(s)
- Di Ran
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Yonggang Ma
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Wei Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Tongwang Luo
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Jiaming Zheng
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Dedong Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Ruilong Song
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Hongyan Zhao
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Hui Zou
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Jianhong Gu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Yan Yuan
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Jianchun Bian
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China
| | - Zongping Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, 225009, PR China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, 225009, PR China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, PR China.
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22
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Exercise and dietary intervention ameliorate high-fat diet-induced NAFLD and liver aging by inducing lipophagy. Redox Biol 2020; 36:101635. [PMID: 32863214 PMCID: PMC7365984 DOI: 10.1016/j.redox.2020.101635] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 06/25/2020] [Accepted: 07/03/2020] [Indexed: 02/08/2023] Open
Abstract
Exercise and dietary intervention are currently available strategies to treat nonalcoholic fatty liver disease (NAFLD), while the underlying mechanism remains controversial. Emerging evidence shows that lipophagy is involved in the inhibition of the lipid droplets accumulation. However, it is still unclear if exercise and dietary intervention improve NAFLD through regulating lipophagy, and how exercise of skeletal muscle can modulate lipid metabolism in liver. Moreover, NAFLD is associated with aging, and little is known about the effect of lipid accumulation on aging process. Here in vivo and in vitro models, we found that exercise and dietary intervention reduced lipid droplets formation, decreased hepatic triglyceride in the liver induced by high-fat diet. Exercise and dietary intervention enhanced the lipophagy by activating AMPK/ULK1 and inhibiting Akt/mTOR/ULK1 pathways respectively. Furthermore, exercise stimulated FGF21 production in the muscle, followed by secretion to the circulation to promote the lipophagy in the liver via an AMPK-dependent pathway. Importantly, for the first time, we demonstrated that lipid accumulation exacerbated liver aging, which was ameliorated by exercise and dietary intervention through inducing lipophagy. Our findings suggested a new mechanism of exercise and dietary intervention to improve NAFLD through promoting lipophagy. The study also provided evidence to support that muscle exercise is beneficial to other metabolic organs such as liver. The FGF21-mediated AMPK dependent lipophagy might be a potential drug target for NAFLD and aging caused by lipid metabolic dysfunction.
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Houzelle A, Dahlmans D, Nascimento EBM, Schaart G, Jörgensen JA, Moonen-Kornips E, Kersten S, Wang X, Hoeks J. MicroRNA-204-5p modulates mitochondrial biogenesis in C2C12 myotubes and associates with oxidative capacity in humans. J Cell Physiol 2020; 235:9851-9863. [PMID: 32452584 PMCID: PMC7586823 DOI: 10.1002/jcp.29797] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 03/24/2020] [Accepted: 04/15/2020] [Indexed: 12/16/2022]
Abstract
Using an unbiased high‐throughput microRNA (miRNA)‐silencing screen combined with functional readouts for mitochondrial oxidative capacity in C2C12 myocytes, we previously identified 19 miRNAs as putative regulators of skeletal muscle mitochondrial metabolism. In the current study, we highlight miRNA‐204‐5p, identified from this screen, and further studied its role in the regulation of skeletal muscle mitochondrial function. Following silencing of miRNA‐204‐5p in C2C12 myotubes, gene and protein expression were assessed using quantitative polymerase chain reaction, microarray analysis, and western blot analysis, while morphological changes were studied by confocal microscopy. In addition, miRNA‐204‐5p expression was quantified in human skeletal muscle biopsies and associated with in vivo mitochondrial oxidative capacity. Transcript levels of PGC‐1α (3.71‐fold; p < .01), predicted as an miR‐204‐5p target, as well as mitochondrial DNA copy number (p < .05) and citrate synthase activity (p = .06) were increased upon miRNA‐204‐5p silencing in C2C12 myotubes. Silencing of miRNA‐204‐5p further resulted in morphological changes, induced gene expression of autophagy marker light chain 3 protein b (LC3B; q = .05), and reduced expression of the mitophagy marker FUNDC1 (q = .01). Confocal imaging revealed colocalization between the autophagosome marker LC3B and the mitochondrial marker OxPhos upon miRNA‐204‐5p silencing. Finally, miRNA‐204‐5p was differentially expressed in human subjects displaying large variation in oxidative capacity and its expression levels associated with in vivo measures of skeletal muscle mitochondrial function. In summary, silencing of miRNA‐204‐5p in C2C12 myotubes stimulated mitochondrial biogenesis, impacted on cellular morphology, and altered expression of markers related to autophagy and mitophagy. The association between miRNA‐204‐5p and in vivo mitochondrial function in human skeletal muscle further identifies miRNA‐204‐5p as an interesting modulator of skeletal muscle mitochondrial metabolism.
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Affiliation(s)
- Alexandre Houzelle
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Dennis Dahlmans
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Emmani B M Nascimento
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Gert Schaart
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Johanna A Jörgensen
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Esther Moonen-Kornips
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Sander Kersten
- Division of Human Nutrition, Nutrition, Metabolism and Genomics Group, Wageningen University, Wageningen, The Netherlands
| | - Xu Wang
- Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.,Laboratory of Integrative Systems Physiology, Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Joris Hoeks
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
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Pinto AP, Vieira TS, Marafon BB, Batitucci G, Cabrera EMB, da Rocha AL, Kohama EB, Rodrigues KCC, de Moura LP, Pauli JR, Cintra DE, Ropelle ER, de Freitas EC, da Silva ASR. The Combination of Fasting, Acute Resistance Exercise, and Protein Ingestion Led to Different Responses of Autophagy Markers in Gastrocnemius and Liver Samples. Nutrients 2020; 12:nu12030641. [PMID: 32121154 PMCID: PMC7146592 DOI: 10.3390/nu12030641] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 12/02/2022] Open
Abstract
The present study verified the responses of proteins related to the autophagy pathway after 10 h of fast with resistance exercise and protein ingestion in skeletal muscle and liver samples. The rats were distributed into five experimental groups: control (CT; sedentary and without gavage after fast), exercise immediately (EXE-imm; after fast, rats were submitted to the resistance protocol and received water by gavage immediately after exercise), exercise after 1 h (EXE-1h; after fast, rats were submitted to the resistance protocol and received water by gavage 1 h after exercise), exercise and supplementation immediately after exercise (EXE/Suppl-imm; after fast, rats were submitted to the resistance protocol and received a mix of casein: whey protein 1:1 (w/w) by gavage immediately after exercise), exercise and supplementation 1 h after exercise (EXE/Suppl-1h; after fast, rats were submitted to the resistance protocol and received a mix of casein: whey protein 1:1 (w/w) by gavage 1 h after exercise). In summary, the current findings show that the combination of fasting, acute resistance exercise, and protein blend ingestion (immediately or 1 h after the exercise stimulus) increased the serum levels of leucine, insulin, and glucose, as well as the autophagy protein contents in skeletal muscle, but decreased other proteins related to the autophagic pathway in the liver. These results deserve further mechanistic investigations since athletes are combining fasting with physical exercise to enhance health and performance outcomes.
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Affiliation(s)
- Ana P. Pinto
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, São Paulo 14049-900, Brazil; (A.P.P.); (A.L.d.R.); (E.B.K.)
| | - Tales S. Vieira
- Postgraduate Program in Nutritional Science, State University of São Paulo Júlio de Mesquita Filho (Araraquara). Araraquara, São Paulo 14800-903, Brazil; (T.S.V.); (G.B.); (E.C.d.F.)
| | - Bruno B. Marafon
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, São Paulo 14040-907, Brazil;
| | - Gabriela Batitucci
- Postgraduate Program in Nutritional Science, State University of São Paulo Júlio de Mesquita Filho (Araraquara). Araraquara, São Paulo 14800-903, Brazil; (T.S.V.); (G.B.); (E.C.d.F.)
| | - Elisa M. B. Cabrera
- Institute of Translational Nutrigenetics and Nutrigenomics, Department of Molecular Biology and Genomics, Health Sciences University Center, University of Guadalajara, Guadalajara 44100, Mexico;
| | - Alisson L. da Rocha
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, São Paulo 14049-900, Brazil; (A.P.P.); (A.L.d.R.); (E.B.K.)
| | - Eike B. Kohama
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, São Paulo 14049-900, Brazil; (A.P.P.); (A.L.d.R.); (E.B.K.)
| | - Kellen C. C. Rodrigues
- Laboratory of Molecular Biology of Exercise (LaBMEx), School of Applied Sciences, University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (K.C.C.R.); (L.P.d.M.); (J.R.P.); (D.E.C.); (E.R.R.)
| | - Leandro P. de Moura
- Laboratory of Molecular Biology of Exercise (LaBMEx), School of Applied Sciences, University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (K.C.C.R.); (L.P.d.M.); (J.R.P.); (D.E.C.); (E.R.R.)
| | - José R. Pauli
- Laboratory of Molecular Biology of Exercise (LaBMEx), School of Applied Sciences, University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (K.C.C.R.); (L.P.d.M.); (J.R.P.); (D.E.C.); (E.R.R.)
| | - Dennys E. Cintra
- Laboratory of Molecular Biology of Exercise (LaBMEx), School of Applied Sciences, University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (K.C.C.R.); (L.P.d.M.); (J.R.P.); (D.E.C.); (E.R.R.)
| | - Eduardo R. Ropelle
- Laboratory of Molecular Biology of Exercise (LaBMEx), School of Applied Sciences, University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (K.C.C.R.); (L.P.d.M.); (J.R.P.); (D.E.C.); (E.R.R.)
| | - Ellen C. de Freitas
- Postgraduate Program in Nutritional Science, State University of São Paulo Júlio de Mesquita Filho (Araraquara). Araraquara, São Paulo 14800-903, Brazil; (T.S.V.); (G.B.); (E.C.d.F.)
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, São Paulo 14040-907, Brazil;
| | - Adelino S. R. da Silva
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, São Paulo 14049-900, Brazil; (A.P.P.); (A.L.d.R.); (E.B.K.)
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, São Paulo 14040-907, Brazil;
- Correspondence: ; Tel.: +55-16-33150522; Fax: +55-16-33150551
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Late Exercise Preconditioning Promotes Autophagy against Exhaustive Exercise-Induced Myocardial Injury through the Activation of the AMPK-mTOR-ULK1 Pathway. BIOMED RESEARCH INTERNATIONAL 2019; 2019:5697380. [PMID: 32656262 PMCID: PMC7322587 DOI: 10.1155/2019/5697380] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 08/10/2019] [Indexed: 02/02/2023]
Abstract
Accumulating evidence shows that the AMPK-mTOR pathway modulates autophagy via coordinated phosphorylation of ULK1. The aim of the present study was to investigate the relationship between AMPK, mTOR, and ULK1 during late exercise preconditioning (LEP), and to explore whether LEP-induced myocardial protection is related to the autophagy. The exercise preconditioning (EP) protocol was as follows: rats were instructed to for run four repeated in duration of 10 minutes (including 10 minutes rest between each period) on a treadmill. Exhaustive exercise (EE) after LEP pretreatment and administration of wortmannin (an autophagy inhibitor that suppresses Class III PI3K-kinase (PI3KC3) activity) were added to test the protective effect. Cardiac troponin I (cTnI), and transmission electron microscopy (TEM), along with hematoxylin-basic fuchsin-picric acid (HBFP) staining, were used to evaluate the myocardial ischemic-hypoxic injury and protection. Western blot was used to analyze the relationship of autophagy-associated proteins. Exhaustive exercise caused severe myocardial ischemic-hypoxic injury, which led to an increase in cTnI levels, changes of ischemia–hypoxia, and cells ultrastructure. Compared with the EE group, LEP significantly suppressed exhaustive exercise-induced myocardial injury. However, wortmannin attenuated LEP-induced myocardial protection by inhibiting autophagy. Compared with the C group, AMPK was increased in the LEP, EE, and LEP+EE groups, but phosphorylation of AMPK at Thr172 was not significantly changed. Exercise did not have any effect on mTOR expression. Compared with the C group, ULK1 was increased and the ULK1ser757/ULK1 ratio was decreased in the LEP and LEP+EE groups. ULK1 was not significantly affected in the EE group, however, phosphorylation of ULK1 at Ser757 was remarkably decreased. To sum up, our results suggested that LEP promoted autophagy through the activation of AMPK-mTOR-ULK1 pathway, and that activated autophagy was partially involved in myocardial protection against EE-induced myocardial ischemic-hypoxic injury.
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26
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Exercise Mitigates the Loss of Muscle Mass by Attenuating the Activation of Autophagy during Severe Energy Deficit. Nutrients 2019; 11:nu11112824. [PMID: 31752260 PMCID: PMC6893734 DOI: 10.3390/nu11112824] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 10/30/2019] [Accepted: 11/14/2019] [Indexed: 01/07/2023] Open
Abstract
The loss of skeletal muscle mass with energy deficit is thought to be due to protein breakdown by the autophagy-lysosome and the ubiquitin-proteasome systems. We studied the main signaling pathways through which exercise can attenuate the loss of muscle mass during severe energy deficit (5500 kcal/day). Overweight men followed four days of caloric restriction (3.2 kcal/kg body weight day) and prolonged exercise (45 min of one-arm cranking and 8 h walking/day), and three days of control diet and restricted exercise, with an intra-subject design including biopsies from muscles submitted to distinct exercise volumes. Gene expression and signaling data indicate that the main catabolic pathway activated during severe energy deficit in skeletal muscle is the autophagy-lysosome pathway, without apparent activation of the ubiquitin-proteasome pathway. Markers of autophagy induction and flux were reduced by exercise primarily in the muscle submitted to an exceptional exercise volume. Changes in signaling are associated with those in circulating cortisol, testosterone, cortisol/testosterone ratio, insulin, BCAA, and leucine. We conclude that exercise mitigates the loss of muscle mass by attenuating autophagy activation, blunting the phosphorylation of AMPK/ULK1/Beclin1, and leading to p62/SQSTM1 accumulation. This includes the possibility of inhibiting autophagy as a mechanism to counteract muscle loss in humans under severe energy deficit.
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Riis S, Møller AB, Dollerup O, Høffner L, Jessen N, Madsen K. Acute and sustained effects of a periodized carbohydrate intake using the sleep-low model in endurance-trained males. Scand J Med Sci Sports 2019; 29:1866-1880. [PMID: 31430404 DOI: 10.1111/sms.13541] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 08/12/2019] [Accepted: 08/15/2019] [Indexed: 12/19/2022]
Abstract
Repeated periodization of carbohydrate (CHO) intake using a diet-exercise strategy called the sleep-low model can potentially induce mitochondrial biogenesis and improve endurance performance in endurance-trained individuals. However, more studies are needed to confirm the performance-related effects and to investigate the sustained effects on maximal fat oxidation (MFO) rate and proteins involved in intramuscular lipid metabolism. Thirteen endurance-trained males (age 23-44 years; V ˙ O2 -max, 63.9 ± 4.6 mL·kg-1 ·min-1 ) were randomized into two groups: sleep-low (LOW-CHO) or high CHO availability (HIGH-CHO) in three weekly training blocks over 4 weeks. The acute metabolic response was investigated during 60 minutes of exercise within the last 3 weeks of the intervention. Pre- and post-intervention, 30-minute time-trial performance was investigated after a 90-minute pre-load, which as a novel approach included nine intense intervals (and estimation of MFO). Additionally, muscle biopsies (v. lateralis) were obtained to investigate expression of proteins involved in intramuscular lipid metabolism using Western blotting. During acute exercise, average fat oxidation rate was ~36% higher in LOW-CHO compared to HIGH-CHO (P = .03). This did not translate into sustained effects on MFO. Time-trial performance increased equally in both groups (overall time effect: P = .005). We observed no effect on intramuscular proteins involved in lipolysis (ATGL, G0S2, CGI-58, HSL) or fatty acid transport and β-oxidation (CD-36 and HAD, respectively). In conclusion, the sleep-low model did not induce sustained effects on MFO, endurance performance, or proteins involved in intramuscular lipid metabolism when compared to HIGH-CHO. Our study therefore questions the transferability of acute effects of the sleep-low model to superior sustained adaptations.
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Affiliation(s)
- Simon Riis
- Section for Sport Science, Department of Public Health, Aarhus University, Aarhus, Denmark.,Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Andreas Buch Møller
- Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Ole Dollerup
- Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital, Denmark
| | - Line Høffner
- Section for Sport Science, Department of Public Health, Aarhus University, Aarhus, Denmark.,Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Niels Jessen
- Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Klavs Madsen
- Section for Sport Science, Department of Public Health, Aarhus University, Aarhus, Denmark.,Norwegian School of Sport Sciences, Oslo, Norway
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28
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Tyganov SA, Mochalova EP, Belova SP, Sharlo KA, Rozhkov SV, Vilchinskaya NA, Paramonova II, Mirzoev TM, Shenkman BS. Effects of Plantar Mechanical Stimulation on Anabolic and Catabolic Signaling in Rat Postural Muscle Under Short-Term Simulated Gravitational Unloading. Front Physiol 2019; 10:1252. [PMID: 31611819 PMCID: PMC6776874 DOI: 10.3389/fphys.2019.01252] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 09/12/2019] [Indexed: 12/18/2022] Open
Abstract
It is known that plantar mechanical stimulation (PMS) is able to attenuate unloading-induced skeletal muscle atrophy and impaired muscle function. However, molecular mechanisms underlying the effect of PMS on skeletal muscle during unloading remain undefined. The aim of the study was to evaluate the effects of PMS on anabolic and catabolic signaling pathways in rat soleus at the early stages of mechanical unloading. Wistar rats were randomly assigned to ambulatory control, hindlimb suspension (HS) for 1 or 3 days, and HS for 1 or 3 days with PMS. The key anabolic and catabolic markers were assessed by western blotting and RT-PCR. Protein synthesis (PS) rate was estimated using SUnSET technique. PMS attenuated a 1-day HS-induced decrease in 4E-BP1, GSK-3β, and AMPK phosphorylation. PMS also partially prevented a decrease in PS, phosphorylation of GSK-3β, nNOS, and an increase in eEF2 phosphorylation after 3-day HS. PMS during 1- and 3-day HS prevented MuRF-1, but not MAFbx, upregulation but did not affect markers of ribosome biogenesis (18S + 28S rRNA, c-myc) as well as AKT phosphorylation. Thus, PMS during 3-day HS partially prevented a decrease in the global rate of PS in rat soleus muscle, which was accompanied by attenuation of MuRF-1 mRNA expression as well as changes in GSK-3β, nNOS, and eEF2 phosphorylation.
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Affiliation(s)
- Sergey A Tyganov
- Myology Laboratory, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Ekaterina P Mochalova
- Myology Laboratory, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Svetlana P Belova
- Myology Laboratory, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Kristina A Sharlo
- Myology Laboratory, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Sergey V Rozhkov
- Myology Laboratory, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Natalia A Vilchinskaya
- Myology Laboratory, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Inna I Paramonova
- Myology Laboratory, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Timur M Mirzoev
- Myology Laboratory, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Boris S Shenkman
- Myology Laboratory, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
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29
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Cui X, Zhang Y, Wang Z, Yu J, Kong Z, Ružić L. High-intensity interval training changes the expression of muscle RING-finger protein-1 and muscle atrophy F-box proteins and proteins involved in the mechanistic target of rapamycin pathway and autophagy in rat skeletal muscle. Exp Physiol 2019; 104:1505-1517. [PMID: 31357248 DOI: 10.1113/ep087601] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 07/17/2019] [Indexed: 12/18/2022]
Abstract
NEW FINDINGS What is the central question of this study? What are the adaptations of protein synthesis and degradation that occur in skeletal muscle in response to high-intensity interval training (HIIT), and what are the magnitudes of the changes in response to HIIT, compared to moderate-intensity continuous training (MICT), and the mechanisms underlying these changes? What is the main finding and its importance? HIIT is more effective than MICT in altering the expression of muscle RING-finger protein-1 and muscle atrophy F-box, and enhancing the autophagic flux in rat soleus muscle. In addition, HIIT could activate the mechanistic target of rapamycin pathway. These findings suggest that HIIT might be an effective exercise strategy for health promotion in skeletal muscle. ABSTRACT This study aimed to investigate the impact of high-intensity interval training (HIIT) on the proteins involved in protein synthesis, the ubiquitin-proteasome system (UPS) and autophagy in skeletal muscle of middle-aged rats. Nine-month-old male Wistar rats (n = 56) were randomly divided into three groups: a control (C) group, a moderate-intensity continuous training (MICT) group and a HIIT group. Rats in the training groups ran on treadmills 5 days per week for 8 weeks. The MICT group ran for 50 min at 60% V ̇ O 2 max , while the HIIT group ran for 3 min at 80% of V ̇ O 2 max six times separated by 3-min periods at 40% V ̇ O 2 max . Aerobic endurance, number of autophagosomes and expression of proteins involved in protein synthesis and degradation in the soleus muscle were measured at three time points: before training, after 4 weeks and after 8 weeks of training. Compared to the C group, HIIT and MICT increased the expression of phosphorylated mechanistic target of rapamycin (mTOR) after 8 weeks (P < 0.05 and P < 0.01, respectively). HIIT increased the expression of muscle RING-finger protein-1 (MuRF-1) after 4 weeks (P < 0.01), and decreased its expression after 8 weeks (P < 0.01). Both HIIT and MICT decreased the expression of muscle atrophy F-box (MAFbx) after 4 weeks (P < 0.05). HIIT improved the expression of microtubule-associated protein 1A/1B-light chain 3 (LC3)-II (P < 0.05), and decreased the P62 content (P < 0.01) after 4 weeks. The LC3II/LC3I ratio was increased after 8 weeks (P < 0.01). This study demonstrated that HIIT could activate the mTOR pathway, alter the expression of MuRF-1 and MAFbx proteins, and enhance autophagic flux in soleus muscle of middle-aged rats.
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Affiliation(s)
- Xinwen Cui
- China Institute of Sport Science, Dongcheng District, Beijing, China.,Beijing Sport University, Haidian District, Beijing, China
| | - Yimin Zhang
- Beijing Sport University, Haidian District, Beijing, China
| | - Zan Wang
- Beijing Sport University, Haidian District, Beijing, China
| | - Jingjing Yu
- Beijing Sport University, Haidian District, Beijing, China
| | - Zhenxing Kong
- Beijing Sport University, Haidian District, Beijing, China
| | - Lana Ružić
- Faculty of Kinesiology, University of Zagreb, Department of Sport and Exercise Medicine, Zagreb, Croatia
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30
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Møller AB, Vendelbo MH, Schjerling P, Couppé C, Møller N, Kjær M, Hansen M, Jessen N. Immobilization Decreases FOXO3a Phosphorylation and Increases Autophagy-Related Gene and Protein Expression in Human Skeletal Muscle. Front Physiol 2019; 10:736. [PMID: 31258486 PMCID: PMC6587099 DOI: 10.3389/fphys.2019.00736] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 05/27/2019] [Indexed: 01/07/2023] Open
Abstract
Immobilization of the lower limbs promotes a catabolic state that reduces muscle mass, whereas physical training promotes an anabolic state that increases muscle mass. Understanding the molecular mechanisms underlying this is of clinical interest, as loss of muscle mass is a major complication to critical illness in humans. To determine the molecular regulation of protein synthesis and degradation during muscle loss and hypertrophy, we examined skeletal muscle biopsies from healthy human subjects after 2 weeks unilateral immobilization of a lower limb and during 6 weeks of physical rehabilitation. We have previously shown that cross-sectional area of the knee muscle-extensors decreased by ∼10% during immobilization and was completely restored during rehabilitation. Here we provide novel data to suggest that autophagy is an important underlying mechanism involved in regulation of muscle mass. Protein expression of MuRF1 and ATROGIN-1 did not change during the study, indicating that the recruitment of substrates to the proteasomes was unaltered. Phosphorylation of mTORat Ser2448 did not change during the study, and neither did phosphorylation of the mTORC1 substrates 4EBP1 Thr37/46 and p70S6K Thr389, suggesting that this pathway does not suppress protein synthesis during muscle wasting. Protein levels of p62 and ULK1 increased during immobilization and returned to baseline levels during rehabilitation. Same pattern was observed for FOXO3a phosphorylation at Ser318/321, suggesting transcriptional activation during immobilization and inactivation during rehabilitation. To investigate this further, we analyzed mRNA expression of seven autophagy-related genes controlled by FOXO3a. Five of these (p62, LC3B, BECLIN-1, ATG12, and BNIP3) increased during immobilization and returned to baseline during rehabilitation. In conclusion, immobilization of a lower limb increases autophagy-related gene and protein expression in human skeletal muscle in a pattern that mirrors FOXO3a phosphorylation. These findings could imply that FOXO3a dependent transcriptional regulation of autophagy is involved in the regulation of muscle mass in humans.
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Affiliation(s)
- Andreas Buch Møller
- Research Laboratory for Biochemical Pathology, Institute for Clinical Medicine, Aarhus University, Aarhus, Denmark.,Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Mikkel Holm Vendelbo
- Department of Nuclear Medicine & PET-Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Peter Schjerling
- Department of Orthopaedic Surgery M, Bispebjerg Hospital, and Center for Healthy Aging, Faculty of Health and Medical Sciences, Institute of Sports Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Christian Couppé
- Department of Orthopaedic Surgery M, Bispebjerg Hospital, and Center for Healthy Aging, Faculty of Health and Medical Sciences, Institute of Sports Medicine, University of Copenhagen, Copenhagen, Denmark.,Musculoskeletal Rehabilitation Research Unit, Department of Physical Therapy, Bispebjerg Hospital, Copenhagen, Denmark
| | - Niels Møller
- Medical Research Laboratory, Institute for Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Michael Kjær
- Department of Orthopaedic Surgery M, Bispebjerg Hospital, and Center for Healthy Aging, Faculty of Health and Medical Sciences, Institute of Sports Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Mette Hansen
- Department of Orthopaedic Surgery M, Bispebjerg Hospital, and Center for Healthy Aging, Faculty of Health and Medical Sciences, Institute of Sports Medicine, University of Copenhagen, Copenhagen, Denmark.,Section of Sports Science, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Niels Jessen
- Research Laboratory for Biochemical Pathology, Institute for Clinical Medicine, Aarhus University, Aarhus, Denmark.,Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
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Recent Data on Cellular Component Turnover: Focus on Adaptations to Physical Exercise. Cells 2019; 8:cells8060542. [PMID: 31195688 PMCID: PMC6627613 DOI: 10.3390/cells8060542] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 05/31/2019] [Accepted: 06/02/2019] [Indexed: 12/22/2022] Open
Abstract
Significant progress has expanded our knowledge of the signaling pathways coordinating muscle protein turnover during various conditions including exercise. In this manuscript, the multiple mechanisms that govern the turnover of cellular components are reviewed, and their overall roles in adaptations to exercise training are discussed. Recent studies have highlighted the central role of the energy sensor (AMP)-activated protein kinase (AMPK), forkhead box class O subfamily protein (FOXO) transcription factors and the kinase mechanistic (or mammalian) target of rapamycin complex (MTOR) in the regulation of autophagy for organelle maintenance during exercise. A new cellular trafficking involving the lysosome was also revealed for full activation of MTOR and protein synthesis during recovery. Other emerging candidates have been found to be relevant in organelle turnover, especially Parkin and the mitochondrial E3 ubiquitin protein ligase (Mul1) pathways for mitochondrial turnover, and the glycerolipids diacylglycerol (DAG) for protein translation and FOXO regulation. Recent experiments with autophagy and mitophagy flux assessment have also provided important insights concerning mitochondrial turnover during ageing and chronic exercise. However, data in humans are often controversial and further investigations are needed to clarify the involvement of autophagy in exercise performed with additional stresses, such as hypoxia, and to understand the influence of exercise modality. Improving our knowledge of these pathways should help develop therapeutic ways to counteract muscle disorders in pathological conditions.
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Sieljacks P, Wang J, Groennebaek T, Rindom E, Jakobsgaard JE, Herskind J, Gravholt A, Møller AB, Musci RV, de Paoli FV, Hamilton KL, Miller BF, Vissing K. Six Weeks of Low-Load Blood Flow Restricted and High-Load Resistance Exercise Training Produce Similar Increases in Cumulative Myofibrillar Protein Synthesis and Ribosomal Biogenesis in Healthy Males. Front Physiol 2019; 10:649. [PMID: 31191347 PMCID: PMC6548815 DOI: 10.3389/fphys.2019.00649] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 05/08/2019] [Indexed: 12/25/2022] Open
Abstract
Purpose: High-load resistance exercise contributes to maintenance of muscle mass, muscle protein quality, and contractile function by stimulation of muscle protein synthesis (MPS), hypertrophy, and strength gains. However, high loading may not be feasible in several clinical populations. Low-load blood flow restricted resistance exercise (BFRRE) may provide an alternative approach. However, the long-term protein synthetic response to BFRRE is unknown and the myocellular adaptations to prolonged BFRRE are not well described. Methods: To investigate this, 34 healthy young subjects were randomized to 6 weeks of low-load BFRRE, HLRE, or non-exercise control (CON). Deuterium oxide (D2O) was orally administered throughout the intervention period. Muscle biopsies from m. vastus lateralis were collected before and after the 6-week intervention period to assess long-term myofibrillar MPS and RNA synthesis as well as muscle fiber-type-specific cross-sectional area (CSA), satellite cell content, and myonuclei content. Muscle biopsies were also collected in the immediate hours following single-bout exercise to assess signaling for muscle protein degradation. Isometric and dynamic quadriceps muscle strength was evaluated before and after the intervention. Results: Myofibrillar MPS was higher in BFRRE (1.34%/day, p < 0.01) and HLRE (1.12%/day, p < 0.05) compared to CON (0.96%/day) with no significant differences between exercise groups. Muscle RNA synthesis was higher in BFRRE (0.65%/day, p < 0.001) and HLRE (0.55%/day, p < 0.01) compared to CON (0.38%/day) and both training groups increased RNA content, indicating ribosomal biogenesis in response to exercise. BFRRE and HLRE both activated muscle degradation signaling. Muscle strength increased 6-10% in BFRRE (p < 0.05) and 13-23% in HLRE (p < 0.01). Dynamic muscle strength increased to a greater extent in HLRE (p < 0.05). No changes in type I and type II muscle fiber-type-specific CSA, satellite cell content, or myonuclei content were observed. Conclusions: These results demonstrate that BFRRE increases long-term muscle protein turnover, ribosomal biogenesis, and muscle strength to a similar degree as HLRE. These findings emphasize the potential application of low-load BFRRE to stimulate muscle protein turnover and increase muscle function in clinical populations where high loading is untenable.
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Affiliation(s)
- Peter Sieljacks
- Section for Sports Science, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Jakob Wang
- Section for Sports Science, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Thomas Groennebaek
- Section for Sports Science, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Emil Rindom
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | - Jon Herskind
- Section for Sports Science, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Anders Gravholt
- Section for Sports Science, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Andreas B. Møller
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Robert V. Musci
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States
| | | | - Karyn L. Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, United States
| | - Benjamin F. Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States
| | - Kristian Vissing
- Section for Sports Science, Department of Public Health, Aarhus University, Aarhus, Denmark
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Brandt N, Gunnarsson TP, Bangsbo J, Pilegaard H. Exercise and exercise training-induced increase in autophagy markers in human skeletal muscle. Physiol Rep 2019; 6:e13651. [PMID: 29626392 PMCID: PMC5889490 DOI: 10.14814/phy2.13651] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 02/22/2018] [Indexed: 12/17/2022] Open
Abstract
Moderately trained male subjects (mean age 25 years; range 19–33 years) completed an 8‐week exercise training intervention consisting of continuous moderate cycling at 157 ± 20 W for 60 min (MOD; n = 6) or continuous moderate cycling (157 ± 20 W) interspersed by 30‐sec sprints (473 ± 79 W) every 10 min (SPRINT; n = 6) 3 days per week. Sprints were followed by 3:24 min at 102 ± 17 W to match the total work between protocols. A muscle biopsy was obtained before, immediately and 2 h after the first training session as well as at rest after the training session. In both MOD and SPRINT, skeletal muscle AMPKThr172 and ULKSer317 phosphorylation was elevated immediately after exercise, whereas mTORSer2448 and ULKSer757 phosphorylation was unchanged. Two hours after exercise LC3I, LC3II and BNIP3 protein content was overall higher than before exercise with no change in p62 protein. In MOD, Beclin1 protein content was higher immediately and 2 h after exercise than before exercise, while there were no differences within SPRINT. Oxphos complex I, LC3I, BNIP3 and Parkin protein content was higher after the training intervention than before in both groups, while there was no difference in LC3II and p62 protein. Beclin1 protein content was higher after the exercise training intervention only in MOD. Together this suggests that exercise increases markers of autophagy in human skeletal muscle within the first 2 h of recovery and 8 weeks of exercise training increases the capacity for autophagy and mitophagy regulation. Hence, the present findings provide evidence that exercise and exercise training regulate autophagy in human skeletal muscle and that this in general was unaffected by interspersed sprint bouts.
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Affiliation(s)
- Nina Brandt
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Thomas P Gunnarsson
- Section of Integrated Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Jens Bangsbo
- Section of Integrated Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Henriette Pilegaard
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
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McCormick JJ, King KE, Dokladny K, Mermier CM. Effect of Acute Aerobic Exercise and Rapamycin Treatment on Autophagy in Peripheral Blood Mononuclear Cells of Adults With Prediabetes. Can J Diabetes 2019; 43:457-463. [PMID: 31213408 DOI: 10.1016/j.jcjd.2019.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 03/04/2019] [Accepted: 04/12/2019] [Indexed: 01/24/2023]
Abstract
OBJECTIVES Recently, a malfunction of the autophagic pathway has been implicated with impaired glucose metabolism and progression from prediabetes to type 2 diabetes. The aims of this study were to investigate the effect of exercise and rapamycin (RAPA) treatment on the autophagic process in peripheral blood mononuclear cells (PBMCs) from people with prediabetes compared with control subjects. METHODS Two groups matched for age and sex served as participants and included 6 participants with prediabetes (42.4±11.7 years) and 6 control subjects (44.4±11.9 years). Participants exercised at 50% of maximal oxygen consumption for 60 min with 5 min of rest interspersed every 20 min. PBMCs were isolated pre-exercise, immediately postexercise and 4 h after exercise recovery. Additional PBMCs were incubated for 24 h and either exposed to bafilomycin, rapamycin with bafilomycin (RAPA), or no treatment with vehicle (dimethyl sulfoxide). Proteins and mRNA were analyzed via western blot and quantitative real-time polymerase chain reaction, respectively. RESULTS Exercise increased autophagy immediately postexercise and recovered 4 h after exercise in control participants but not in participants with prediabetes. Autophagy increased in PBMCs from people with prediabetes and control participants after RAPA treatment; however, a significantly impaired autophagic response was observed in people with prediabetes when compared with control subjects. CONCLUSIONS Our results indicate an impairment in autophagic flux in PBMCs from people with prediabetes when compared with control subjects in response to both exercise and RAPA treatment. Future methods of autophagic upregulation should be investigated to spare malfunctions in autophagy in people with prediabetes.
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Affiliation(s)
- James J McCormick
- Department of Health, Exercise, and Sports Sciences, University of New Mexico, Albuquerque, New Mexico, United States.
| | - Kelli E King
- Department of Health, Exercise, and Sports Sciences, University of New Mexico, Albuquerque, New Mexico, United States
| | - Karol Dokladny
- Department of Internal Medicine, University of New Mexico, Albuquerque, New Mexico, United States
| | - Christine M Mermier
- Department of Health, Exercise, and Sports Sciences, University of New Mexico, Albuquerque, New Mexico, United States
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Yoo YM, Jung EM, Jeung EB. Rapamycin-induced autophagy decreases Myf5 and MyoD proteins in C2C12 myoblast cells. Toxicol In Vitro 2019; 58:132-141. [PMID: 30905858 DOI: 10.1016/j.tiv.2019.03.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 03/20/2019] [Accepted: 03/20/2019] [Indexed: 12/19/2022]
Abstract
Rapamycin is an immunosuppressant that inhibits the mammalian or mechanistic target of rapamycin (mTOR) protein kinase and extends lifespan in organisms including mice. Myf5 and MyoD act as muscle-specific transcriptional factors for skeletal muscle differentiation. In this study, we determined whether rapamycin-induced autophagy causes the decrease of Myf5 and MyoD protein in C2C12 myoblast cells. Rapamycin induced a significant increase in the expression of the microtubule-associated protein 1 light chain 3 (LC3) II protein in a dose-dependent manner for 12 h. Rapamycin treatment also significantly increased p-ERK, p-Akt, and catalase expressions, and decreased Mn-SOD expression in a dose-dependent manner. Bax expression was significantly high compared to Bcl-2 expression in a dose-dependent manner of rapamycin for 12 h. For further study of rapamycin-induced autophagy in C2C12 myoblast cells, we investigated rapamycin treatment for 24, 36, and 48 h. Cell viability did not change with rapamycin treatment for 24, 36, and 48 h. Rapamycin-induced LC3-II, Beclin-1, Bax, and Bcl-2 proteins were significantly increased compared to without rapamycin. p-ERK expression increased with rapamycin treatment for 24 and 36 h compared to that without rapamycin, but decreased for 48 h. p-Akt expression decreased with rapamycin treatment for 36 and 48 h compared to that without rapamycin. In the same conditions, rapamycin-induced autophagy significantly reduced the Myf5 and MyoD proteins. Together, these results suggest that rapamycin-induced autophagy results in the decrease of Myf5 and MyoD proteins in C2C12 myoblast cells.
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Affiliation(s)
- Yeong-Min Yoo
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea
| | - Eui-Man Jung
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea
| | - Eui-Bae Jeung
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea.
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Escobar KA, Cole NH, Mermier CM, VanDusseldorp TA. Autophagy and aging: Maintaining the proteome through exercise and caloric restriction. Aging Cell 2019; 18:e12876. [PMID: 30430746 PMCID: PMC6351830 DOI: 10.1111/acel.12876] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 08/31/2018] [Accepted: 09/28/2018] [Indexed: 12/16/2022] Open
Abstract
Accumulation of dysfunctional and damaged cellular proteins and organelles occurs during aging, resulting in a disruption of cellular homeostasis and progressive degeneration and increases the risk of cell death. Moderating the accrual of these defunct components is likely a key in the promotion of longevity. While exercise is known to promote healthy aging and mitigate age‐related pathologies, the molecular underpinnings of this phenomenon remain largely unclear. However, recent evidences suggest that exercise modulates the proteome. Similarly, caloric restriction (CR), a known promoter of lifespan, is understood to augment intracellular protein quality. Autophagy is an evolutionary conserved recycling pathway responsible for the degradation, then turnover of cellular proteins and organelles. This housekeeping system has been reliably linked to the aging process. Moreover, autophagic activity declines during aging. The target of rapamycin complex 1 (TORC1), a central kinase involved in protein translation, is a negative regulator of autophagy, and inhibition of TORC1 enhances lifespan. Inhibition of TORC1 may reduce the production of cellular proteins which may otherwise contribute to the deleterious accumulation observed in aging. TORC1 may also exert its effects in an autophagy‐dependent manner. Exercise and CR result in a concomitant downregulation of TORC1 activity and upregulation of autophagy in a number of tissues. Moreover, exercise‐induced TORC1 and autophagy signaling share common pathways with that of CR. Therefore, the longevity effects of exercise and CR may stem from the maintenance of the proteome by balancing the synthesis and recycling of intracellular proteins and thus may represent practical means to promote longevity.
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Affiliation(s)
- Kurt A. Escobar
- Department of Kinesiology; California State University, Long Beach; Long Beach California
| | - Nathan H. Cole
- Department of Health, Exercise, & Sports Sciences; University of New Mexico; Albuquerque New Mexico
| | - Christine M. Mermier
- Department of Health, Exercise, & Sports Sciences; University of New Mexico; Albuquerque New Mexico
| | - Trisha A. VanDusseldorp
- Department of Exercise Science & Sports Management; Kennesaw State University; Kennesaw Georgia
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Høgild ML, Bak AM, Pedersen SB, Rungby J, Frystyk J, Møller N, Jessen N, Jørgensen JOL. Growth hormone signaling and action in obese versus lean human subjects. Am J Physiol Endocrinol Metab 2019; 316:E333-E344. [PMID: 30576246 DOI: 10.1152/ajpendo.00431.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Growth hormone (GH) levels are blunted in obesity, but it is not known whether this relates to altered GH sensitivity and whether this influences the metabolic adaptation to fasting. Therefore, we investigated the effect of obesity on GH signal transduction and fasting-induced changes in GH action. Nine obese (BMI 35.7 kg/m2) and nine lean (BMI 21.5 kg/m2) men were studied in a randomized crossover design with 1) an intravenous GH bolus, 2) an intravenous saline bolus, and 3) 72 h of fasting. Insulin sensitivity (hyperinsulinemic, euglycemic clamp) and substrate metabolism (glucose tracer and indirect calorimetry) were measured in studies 1 and 2. In vivo GH signaling was assessed in muscle and fat biopsies. GH pharmacokinetics did not differ between obese and lean subjects, but endogenous GH levels were reduced in obesity. GH signaling (STAT5b phosphorylation and CISH mRNA transcription), and GH action (induction of lipolysis and peripheral insulin resistance) were similar in the two groups, but a GH-induced insulin antagonistic effect on endogenous glucose production only occurred in the obese. Fasting-induced IGF-I reduction was completely abrogated in obese subjects despite a comparable relative increase in GH levels (ΔIGF-I: lean, -66 ± 10 vs. obese, 27 ± 16 µg/l; P < 0.01; ΔGH: lean, 647 ± 280 vs. obese, 544 ± 220%; P = 0.76]. We conclude that 1) GH signaling is normal in obesity, 2) in the obese state, the preservation of IGF-I with fasting and the augmented GH-induced central insulin resistance indicate increased hepatic GH sensitivity, 3) blunted GH levels in obesity may protect against insulin resistance without compromising IGF-I status.
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Affiliation(s)
- Morten Lyng Høgild
- Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital , Denmark
- Department of Clinical Medicine, Aarhus University , Denmark
| | - Ann Mosegaard Bak
- Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital , Denmark
- Department of Clinical Medicine, Aarhus University , Denmark
| | - Steen Bønløkke Pedersen
- Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital , Denmark
- Department of Clinical Medicine, Aarhus University , Denmark
| | - Jørgen Rungby
- Department of Biomedicine, Aarhus University , Denmark
| | - Jan Frystyk
- Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital , Denmark
- Department of Clinical Medicine, Aarhus University , Denmark
| | - Niels Møller
- Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital , Denmark
- Department of Clinical Medicine, Aarhus University , Denmark
| | - Niels Jessen
- Department of Clinical Medicine, Aarhus University , Denmark
- Department of Biomedicine, Aarhus University , Denmark
- Department of Clinical Pharmacology, Aarhus University Hospital , Denmark
| | - Jens O L Jørgensen
- Medical Research Laboratory, Department of Clinical Medicine, Aarhus University Hospital , Denmark
- Department of Clinical Medicine, Aarhus University , Denmark
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Li Z, Rasmussen ML, Li J, Henriquez-Olguin C, Knudsen JR, Madsen AB, Sanchez-Quant E, Kleinert M, Jensen TE. Periodized low protein-high carbohydrate diet confers potent, but transient, metabolic improvements. Mol Metab 2018; 17:112-121. [PMID: 30193785 PMCID: PMC6197680 DOI: 10.1016/j.molmet.2018.08.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 08/21/2018] [Accepted: 08/22/2018] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVE Chronic ad libitum low protein-high carbohydrate diet (LPHC) increases health- and life-span in mice. A periodized (p) LPHC regimen would be a more practical long-term human lifestyle intervention, but the metabolic benefits of pLPHC are not known. Also, the interactions between LPHC diet and exercise training have not been investigated. Presently, we aimed to provide proof-of-concept data in mice of the efficacy of pLPHC and to explore the potential interactions with concurrent exercise training. METHODS A detailed phenotypic and molecular characterization of mice undergoing different durations of 14 d LPHC (5 E% protein)/14 d control diet cycles for up to 4 months with or without concurrent access to activity wheels allowing voluntary exercise training. RESULTS pLPHC conferred metabolic benefits similar to chronic LPHC, including increased FGF21 and adaptive thermogenesis, obesity-protection despite increased total energy intake and improved insulin sensitivity. The improved insulin sensitivity showed large fluctuations between diet periods and was lost within 14 days of switching back to control diet. Parallel exercise training improved weight maintenance but impaired the FGF21 response to pLPHC whereas repeated pLPHC cycles progressively augmented this response. Both the FGF21 suppression by exercise and potentiation by repeated cycles correlated tightly with Nupr1 mRNA in liver, suggesting dependence on liver integrated stress response. CONCLUSION These results suggest that pLPHC may be a viable strategy to promote human health but also highlight the transient nature of the benefits and that the interaction with other lifestyle-interventions such as exercise training warrants consideration.
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Affiliation(s)
- Zhencheng Li
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Mette Line Rasmussen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Jingwen Li
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Carlos Henriquez-Olguin
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Jonas Roland Knudsen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Agnete Bjerregaard Madsen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Eva Sanchez-Quant
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany
| | - Maximilian Kleinert
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, 2100, Denmark; Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany
| | - Thomas Elbenhardt Jensen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, 2100, Denmark.
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Training-Induced Changes in Mitochondrial Content and Respiratory Function in Human Skeletal Muscle. Sports Med 2018; 48:1809-1828. [PMID: 29934848 DOI: 10.1007/s40279-018-0936-y] [Citation(s) in RCA: 124] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A sedentary lifestyle has been linked to a number of metabolic disorders that have been associated with sub-optimal mitochondrial characteristics and an increased risk of premature death. Endurance training can induce an increase in mitochondrial content and/or mitochondrial functional qualities, which are associated with improved health and well-being and longer life expectancy. It is therefore important to better define how manipulating key parameters of an endurance training intervention can influence the content and functionality of the mitochondrial pool. This review focuses on mitochondrial changes taking place following a series of exercise sessions (training-induced mitochondrial adaptations), providing an in-depth analysis of the effects of exercise intensity and training volume on changes in mitochondrial protein synthesis, mitochondrial content and mitochondrial respiratory function. We provide evidence that manipulation of different exercise training variables promotes specific and diverse mitochondrial adaptations. Specifically, we report that training volume may be a critical factor affecting changes in mitochondrial content, whereas relative exercise intensity is an important determinant of changes in mitochondrial respiratory function. As a consequence, a dissociation between training-induced changes in mitochondrial content and mitochondrial respiratory function is often observed. We also provide evidence that exercise-induced changes are not necessarily predictive of training-induced adaptations, we propose possible explanations for the above discrepancies and suggestions for future research.
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40
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Exercise and the control of muscle mass in human. Pflugers Arch 2018; 471:397-411. [DOI: 10.1007/s00424-018-2217-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 10/02/2018] [Accepted: 10/04/2018] [Indexed: 12/19/2022]
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Hentilä J, Ahtiainen JP, Paulsen G, Raastad T, Häkkinen K, Mero AA, Hulmi JJ. Autophagy is induced by resistance exercise in young men, but unfolded protein response is induced regardless of age. Acta Physiol (Oxf) 2018; 224:e13069. [PMID: 29608242 DOI: 10.1111/apha.13069] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 03/12/2018] [Accepted: 03/24/2018] [Indexed: 12/13/2022]
Abstract
AIM Autophagy and unfolded protein response (UPR) appear to be important for skeletal muscle homoeostasis and may be altered by exercise. Our aim was to investigate the effects of resistance exercise and training on indicators of UPR and autophagy in healthy untrained young men (n = 12, 27 ± 4 years) and older men (n = 8, 61 ± 6 years) as well as in resistance-trained individuals (n = 15, 25 ± 5 years). METHODS Indicators of autophagy and UPR were investigated from the muscle biopsies after a single resistance exercise bout and after 21 weeks of resistance training. RESULTS Lipidated LC3II as an indicator of autophagosome content increased at 48 hours post-resistance exercise (P < .05) and after a resistance training period (P < .01) in untrained young men but not in older men. Several UPRER markers, typically induced by protein misfolding in endoplasmic reticulum, were increased at 48 hours post-resistance exercise in untrained young and older men (P < .05) but were unaltered after the 21-week resistance training period regardless of age. UPR was unchanged within the first few hours after the resistance exercise bout regardless of the training status. Changes in autophagy and UPRER indicators did not correlate with a resistance training-induced increase in muscle strength and size. CONCLUSION Autophagosome content is increased by resistance training in young previously untrained men, but this response may be blunted by ageing. However, unfolded protein response is induced by an unaccustomed resistance exercise bout in a delayed manner regardless of age.
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Affiliation(s)
- J. Hentilä
- Biology of Physical Activity; Neuromuscular Research Center; Faculty of Sport and Health Sciences; University of Jyväskylä; Jyväskylä Finland
| | - J. P. Ahtiainen
- Biology of Physical Activity; Neuromuscular Research Center; Faculty of Sport and Health Sciences; University of Jyväskylä; Jyväskylä Finland
| | - G. Paulsen
- The Norwegian Olympic and Paralympic Committee and Confederation of Sports; Oslo Norway
| | - T. Raastad
- Department of Physical Performance; Norwegian School of Sport Sciences; Oslo Norway
| | - K. Häkkinen
- Biology of Physical Activity; Neuromuscular Research Center; Faculty of Sport and Health Sciences; University of Jyväskylä; Jyväskylä Finland
| | - A. A. Mero
- Biology of Physical Activity; Neuromuscular Research Center; Faculty of Sport and Health Sciences; University of Jyväskylä; Jyväskylä Finland
| | - J. J. Hulmi
- Biology of Physical Activity; Neuromuscular Research Center; Faculty of Sport and Health Sciences; University of Jyväskylä; Jyväskylä Finland
- Department of Physiology; Faculty of Medicine; University of Helsinki; Helsinki Finland
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Møller AB, Voss TS, Vendelbo MH, Pedersen SB, Møller N, Jessen N. Insulin inhibits autophagy signaling independent of counter-regulatory hormone levels, but does not affect the effects of exercise. J Appl Physiol (1985) 2018; 125:1204-1209. [PMID: 30070610 DOI: 10.1152/japplphysiol.00490.2018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Acute exercise increases autophagic signaling through ULK1 in human skeletal muscle during both anabolic and catabolic conditions. The aim of the present study was to investigate if changes in ULK1 Ser555 phosphorylation during exercise are reflected by changes in phosphorylation of a newly identified ULK1 substrate (ATG14 Ser29), and to elucidate the involvement of circulatory hormones in regulation of autophagy in human skeletal muscle. We show that one hour of cycling exercise increases ATG14 Ser29 phosphorylation during both hyperinsulinemic euglycemic and euinsulinemic euglycemic conditions. This could suggest that counter-regulatory hormones stimulate autophagy in skeletal muscle, as circulating concentrations of these hormones are highly elevated during exercise. Furthermore, ATG14 Ser29 correlated positively with ULK1 phosphorylation, suggesting that ULK1 Ser555 (activating site) phosphorylation reflects ULK1 kinase activity. In a separate series of experiments, we show that insulin stimulates ULK1 phosphorylation at Ser757 (inhibitory site) in both hypoglycemic and euglycemic conditions, suggesting that counter-regulatory hormones (such as epinephrine, norepinephrine, growth hormone and glucagon) have limited effects on autophagy signaling in human skeletal muscle. In conclusion, one hour of cycling exercise increases phosphorylation of ATG14 at Ser29 in a pattern that mirrors ULK1 phosphorylation at Ser555. Moreover, insulin effects on autophagy signaling in human skeletal muscle are independent of hypoglycemic and euglycemic conditions.
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Affiliation(s)
- Andreas Buch Møller
- Research Laboratory for Biochemical PathologyDepartment of Clinical Medicine, Aarhus University, Denmark
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Moberg M, Hendo G, Jakobsson M, Mattsson CM, Ekblom-Bak E, Flockhart M, Pontén M, Söderlund K, Ekblom B. Increased autophagy signaling but not proteasome activity in human skeletal muscle after prolonged low-intensity exercise with negative energy balance. Physiol Rep 2018; 5. [PMID: 29208687 PMCID: PMC5727276 DOI: 10.14814/phy2.13518] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 11/02/2017] [Indexed: 01/01/2023] Open
Abstract
Little is known about the molecular regulation of skeletal muscle protein turnover during exercise in field conditions where energy is intake inadequate. Here, 17 male and 7 female soldiers performed an 8 days long field-based military operation. Vastus lateralis muscle biopsies, in which autophagy, the ubiquitin-proteasome system, and the mTORC1 signaling pathway were studied, were collected before and after the operation. The 187 h long operation resulted in a 15% and 29% negative energy balance as well as a 4.1% and 4.6% loss of body mass in women and men, respectively. After the operation protein levels of ULK1 as well as the phosphorylation of ULK1Ser317 and ULK1Ser555 had increased by 11%, 39%, and 13%, respectively, and this was supported by a 17% increased phosphorylation of AMPKThr172 (P < 0.05). The LC3b-I/II ratio was threefold higher after compared to before the operation (P < 0.05), whereas protein levels of p62/SQSTM1 were unchanged. The β1, β2, and β5 activity of the proteasome and protein levels of MAFbx did not change, whereas levels of MuRF-1 were slightly reduced (6%, P < 0.05). Protein levels and phosphorylation status of key components in the mTORC1 signaling pathway remained at basal levels after the operation. Muscle levels of glycogen decreased from 269 ± 12 to 181 ± 9 mmol·kg dry·muscle-1 after the exercise period (P < 0.05). In conclusion, the 8 days of field-based exercise resulted in induction of autophagy without any increase in proteasome activity or protein ubiquitination. Simultaneously, the regulation of protein synthesis through the mTORC1 signaling pathway was maintained.
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Affiliation(s)
- Marcus Moberg
- Åstrand Laboratory of Work Physiology, the Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Gina Hendo
- Åstrand Laboratory of Work Physiology, the Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Madelene Jakobsson
- Åstrand Laboratory of Work Physiology, the Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - C Mikael Mattsson
- Åstrand Laboratory of Work Physiology, the Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Elin Ekblom-Bak
- Åstrand Laboratory of Work Physiology, the Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Mikael Flockhart
- Åstrand Laboratory of Work Physiology, the Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Marjan Pontén
- Åstrand Laboratory of Work Physiology, the Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Karin Söderlund
- Åstrand Laboratory of Work Physiology, the Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Björn Ekblom
- Åstrand Laboratory of Work Physiology, the Swedish School of Sport and Health Sciences, Stockholm, Sweden
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Ohno Y, Oyama A, Kaneko H, Egawa T, Yokoyama S, Sugiura T, Ohira Y, Yoshioka T, Goto K. Lactate increases myotube diameter via activation of MEK/ERK pathway in C2C12 cells. Acta Physiol (Oxf) 2018; 223:e13042. [PMID: 29377587 DOI: 10.1111/apha.13042] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 01/16/2018] [Accepted: 01/21/2018] [Indexed: 12/22/2022]
Abstract
AIM Lactate is produced in and released from skeletal muscle cells. Lactate receptor, G-protein-coupled receptor 81 (GPR81), is expressed in skeletal muscle cells. However, a physiological role of extracellular lactate on skeletal muscle is not fully clarified. The purpose of this study was to investigate extracellular lactate-associated morphological changes and intracellular signals in C2C12 skeletal muscle cells. METHODS Mouse myoblast C2C12 cells were differentiated for 5 days to form myotubes. Sodium lactate (lactate) or GPR81 agonist, 3,5-dihydroxybenzoic acid (3,5-DHBA), was administered to the differentiation medium. RESULTS Lactate administration increased the diameter of C2C12 myotubes in a dose-dependent manner. Administration of 3,5-DHBA also increased myotube diameter. Not only lactate but also 3,5-DHBA upregulated the phosphorylation level of mitogen-activated protein kinase kinase 1/2 (MEK1/2), p42/44 extracellular signal-regulated kinase-1/2 (ERK1/2) and p90 ribosomal S6 kinase (p90RSK). MEK inhibitor U0126 depressed the phosphorylation of ERK-p90RSK and increase in myotube diameter induced by lactate. On the other hand, both lactate and 3,5-DHBA failed to induce significant responses in the phosphorylation level of Akt, mammalian target of rapamycin, p70 S6 kinase and protein degradation-related signals. CONCLUSION These observations suggest that lactate-associated increase in the diameter of C2C12 myotubes is induced via activation of GRP81-mediated MEK/ERK pathway. Extracellular lactate might have a positive effect on skeletal muscle size.
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Affiliation(s)
- Y. Ohno
- Laboratory of Physiology; School of Health Sciences; Toyohashi SOZO University; Toyohashi Japan
| | - A. Oyama
- Laboratory of Physiology; School of Health Sciences; Toyohashi SOZO University; Toyohashi Japan
| | - H. Kaneko
- Laboratory of Physiology; School of Health Sciences; Toyohashi SOZO University; Toyohashi Japan
| | - T. Egawa
- Department of Physiology; Graduate School of Health Sciences; Toyohashi SOZO University; Toyohashi Japan
| | - S. Yokoyama
- Laboratory of Physiology; School of Health Sciences; Toyohashi SOZO University; Toyohashi Japan
| | - T. Sugiura
- Faculty of Education; Yamaguchi University; Yamaguchi Japan
| | - Y. Ohira
- Graduate School of Health and Sports Science; Doshisha University; Kyotanabe Japan
| | | | - K. Goto
- Laboratory of Physiology; School of Health Sciences; Toyohashi SOZO University; Toyohashi Japan
- Department of Physiology; Graduate School of Health Sciences; Toyohashi SOZO University; Toyohashi Japan
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Sanchez AMJ. Autophagy regulation in human skeletal muscle during exercise. J Physiol 2018; 594:5053-4. [PMID: 27629080 DOI: 10.1113/jp272993] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Affiliation(s)
- Anthony M J Sanchez
- Laboratoire Européen Performance Santé Altitude, University of Perpignan Via Domitia, EA4604, Font-Romeu, France. ,
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mTOR Signaling Pathway and Protein Synthesis: From Training to Aging and Muscle Autophagy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1088:139-151. [PMID: 30390251 DOI: 10.1007/978-981-13-1435-3_7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In muscle tissue there is a balance between the processes muscle synthesis and degradation. The mammalian target of rapamycin (mTOR) signaling pathway plays a critical role in regulating protein synthesis in order to maintain muscular protein turnover and trophism. Studies have shown that both down- and upregulation mechanisms are involved in this process in a manner dependent on stimulus and cellular conditions. Additionally, mTOR signaling has recently been implicated in several physiological conditions related to cell survival, such as self-digestion (autophagy), energy production, and the preservation of cellular metabolic balance over the lifespan. Here we briefly describe the mTOR structure and its regulatory protein synthesis pathway. Furthermore, the role of mTOR protein in autophagy, aging, and mitochondrial function in muscle tissue is presented.
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Cardinale DA, Lilja M, Mandić M, Gustafsson T, Larsen FJ, Lundberg TR. Resistance Training with Co-ingestion of Anti-inflammatory Drugs Attenuates Mitochondrial Function. Front Physiol 2017; 8:1074. [PMID: 29311990 PMCID: PMC5742251 DOI: 10.3389/fphys.2017.01074] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 12/06/2017] [Indexed: 01/09/2023] Open
Abstract
Aim: The current study aimed to examine the effects of resistance exercise with concomitant consumption of high vs. low daily doses of non-steroidal anti-inflammatory drugs (NSAIDs) on mitochondrial oxidative phosphorylation in skeletal muscle. As a secondary aim, we compared the effects of eccentric overload with conventional training. Methods: Twenty participants were randomized to either a group taking high doses (3 × 400 mg/day) of ibuprofen (IBU; 27 ± 5 year; n = 11) or a group ingesting a low dose (1 × 75 mg/day) of acetylsalicylic acid (ASA; 26 ± 4 year; n = 9) during 8 weeks of supervised knee extensor resistance training. Each of the subject's legs were randomized to complete the training program using either a flywheel (FW) device emphasizing eccentric overload, or a traditional weight stack machine (WS). Maximal mitochondrial oxidative phosphorylation (CI+IIP) from permeabilized skeletal muscle bundles was assessed using high-resolution respirometry. Citrate synthase (CS) activity was assessed using spectrophotometric techniques and mitochondrial protein content using western blotting. Results: After training, CI+IIP decreased (P < 0.05) in both IBU (23%) and ASA (29%) with no difference across medical treatments. Although CI+IIP decreased in both legs, the decrease was greater (interaction p = 0.015) in WS (33%, p = 0.001) compared with FW (19%, p = 0.078). CS activity increased (p = 0.027) with resistance training, with no interactions with medical treatment or training modality. Protein expression of ULK1 increased with training in both groups (p < 0.001). The increase in quadriceps muscle volume was not correlated with changes in CI+IIP (R = 0.16). Conclusion: These results suggest that 8 weeks of resistance training with co-ingestion of anti-inflammatory drugs reduces mitochondrial function but increases mitochondrial content. The observed changes were not affected by higher doses of NSAIDs consumption, suggesting that the resistance training intervention was the prime mediator of the decreased mitochondrial phosphorylation. Finally, we noted that flywheel resistance training, emphasizing eccentric overload, rescued some of the reduction in mitochondrial function seen with conventional resistance training.
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Affiliation(s)
- Daniele A Cardinale
- Åstrand Laboratory, The Swedish School of Sport and Health Sciences, Stockholm, Sweden.,Elite Performance Centre, Bosön-Swedish Sports Confederation, Lidingö, Sweden
| | - Mats Lilja
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Mirko Mandić
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Thomas Gustafsson
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Filip J Larsen
- Åstrand Laboratory, The Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Tommy R Lundberg
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
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Mejías-Peña Y, Estébanez B, Rodriguez-Miguelez P, Fernandez-Gonzalo R, Almar M, de Paz JA, González-Gallego J, Cuevas MJ. Impact of resistance training on the autophagy-inflammation-apoptosis crosstalk in elderly subjects. Aging (Albany NY) 2017; 9:408-418. [PMID: 28160545 PMCID: PMC5361672 DOI: 10.18632/aging.101167] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 01/25/2017] [Indexed: 12/13/2022]
Abstract
Aging is associated with a decline in autophagy and a state of low-grade inflammation which further affects apoptosis and autophagy. Importantly, these alterations could reverse with regular physical activity. This study assessed the effects of a resistance exercise training program on autophagy, NLRP3 inflammasome, and apoptosis in peripheral blood mononuclear cells (PBMCs) from old subjects. Twenty-six healthy women and men (age, 69.6±1.5 yr) were randomized to a training (TG) or a control (CG) group. TG performed an 8-week resistance training program, while CG followed their daily routines. Protein expression of beclin-1, Atg12, Atg16 and LAMP-2 increased following the training program, while expression of p62/SQSTM1 and phosphorylation of ULK-1 at Ser757 were significantly lower. Resistance exercise also induced a decrease in NLRP3 expression and in the caspase-1/procaspase-1 ratio. Expression of Bcl-2 and Bcl-xL, as well as the Bad/BcL-2 ratio were reduced, and there was a significant decrease in the protein content of caspase-3. The results obtained seem to indicate that 8-week resistance training stimulates autophagy, prevents NLRP3 inflammasome activation, and reduces apoptosis in PBMCs from elderly subjects. These data could have a significant impact in prevention and rehabilitation programs currently employed in elderly population.
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Affiliation(s)
| | | | - Paula Rodriguez-Miguelez
- Division of Clinical Translational Science, Georgia Prevention Institute, Department of Pediatrics, Augusta University, Augusta, GA, USA
| | - Rodrigo Fernandez-Gonzalo
- Radiobiology Unit, Laboratory of Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK•CEN), Mol, Belgium
| | - Mar Almar
- Institute of Biomedicine (IBIOMED), University of León, León, Spain
| | - José A de Paz
- Institute of Biomedicine (IBIOMED), University of León, León, Spain
| | | | - María J Cuevas
- Institute of Biomedicine (IBIOMED), University of León, León, Spain
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Tarpey MD, Davy KP, McMillan RP, Bowser SM, Halliday TM, Boutagy NE, Davy BM, Frisard MI, Hulver MW. Skeletal muscle autophagy and mitophagy in endurance-trained runners before and after a high-fat meal. Mol Metab 2017; 6:1597-1609. [PMID: 29097020 PMCID: PMC5699914 DOI: 10.1016/j.molmet.2017.10.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 10/04/2017] [Accepted: 10/16/2017] [Indexed: 12/15/2022] Open
Abstract
Objective We tested the hypothesis that skeletal muscle of endurance-trained male runners would exhibit elevated autophagy and mitophagy markers, which would be associated with greater metabolic flexibility following a high-fat meal (HFM). Methods Muscle biopsies were collected to determine differences in autophagy and mitophagy protein markers and metabolic flexibility under fasting conditions and 4 h following a HFM between endurance-trained male runners (n = 10) and sedentary, non-obese controls (n = 9). Results Maximal oxygen consumption (ml·kg·min−1) was approximately 50% higher (p < 0.05) in endurance-trained runners compared with sedentary controls (65.8 ± 2.3 and 43.1 ± 3.4, respectively). Autophagy markers were similar between groups. Mitophagy and mitochondrial dynamics protein markers were significantly higher in skeletal muscle of endurance-trained runners compared with sedentary controls in the fasted state, although unaffected by the HFM. Skeletal muscle metabolic flexibility was similar between groups when fasted (p > 0.05), but increased in response to the HFM in endurance-trained athletes only (p < 0.005). Key mitophagy markers, phospho-Pink1Thr257 and phospho-ParkinS65 (r = 0.64, p < 0.005), and phospo-ParkinSer65 and phospho-Drp1Ser616 (r = 0.70, p < 0.05) were correlated only within the endurance-trained group. Autophagy and mitophagy markers were not correlated with metabolic flexibility. Conclusion In summary, mitophagy may be enhanced in endurance-trained runners based on elevated markers of mitophagy and mitochondrial dynamics. The HFM did not alter autophagy or mitophagy in either group. The absence of a relationship between mitophagy markers and metabolic flexibility suggests that mitophagy is not a key determinant of metabolic flexibility in a healthy population, but further investigation is warranted. Basal autophagy is similar in skeletal muscle of endurance-trained and sedentary males. Trained and sedentary skeletal muscle autophagy is unaltered following high-fat meal. Mitophagy activity is greater in endurance-trained than sedentary skeletal muscle. Greater mitophagy is related to increased metabolic flexibility after high-fat meal. Trained and sedentary skeletal muscle mitophagy is unaltered following high-fat meal.
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Affiliation(s)
- Michael D Tarpey
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA, USA
| | - Kevin P Davy
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA, USA; Metabolic Phenotyping Core, Virginia Tech, Blacksburg, VA, USA; Fralin Translational Obesity Research Center, Virginia Tech, Blacksburg, VA, USA
| | - Ryan P McMillan
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA, USA; Metabolic Phenotyping Core, Virginia Tech, Blacksburg, VA, USA
| | - Suzanne M Bowser
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA, USA
| | - Tanya M Halliday
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA, USA
| | - Nabil E Boutagy
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA, USA
| | - Brenda M Davy
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA, USA; Fralin Translational Obesity Research Center, Virginia Tech, Blacksburg, VA, USA
| | - Madlyn I Frisard
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA, USA; Metabolic Phenotyping Core, Virginia Tech, Blacksburg, VA, USA; Fralin Translational Obesity Research Center, Virginia Tech, Blacksburg, VA, USA
| | - Matthew W Hulver
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, VA, USA; Metabolic Phenotyping Core, Virginia Tech, Blacksburg, VA, USA; Fralin Translational Obesity Research Center, Virginia Tech, Blacksburg, VA, USA.
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50
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Drake JC, Yan Z. Mitophagy in maintaining skeletal muscle mitochondrial proteostasis and metabolic health with ageing. J Physiol 2017; 595:6391-6399. [PMID: 28795394 PMCID: PMC5638883 DOI: 10.1113/jp274337] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 08/05/2017] [Indexed: 12/26/2022] Open
Abstract
Skeletal muscle is important for overall functionality and health. Ageing is associated with an accumulation of damage to mitochondrial DNA and proteins. In particular, damage to mitochondrial proteins in skeletal muscle, which is a loss of mitochondrial proteostasis, contributes to tissue dysfunction and negatively impacts systemic health. Therefore, understanding the mechanisms underlying the regulation of mitochondrial proteostasis and how those mechanisms change with age is important for the development of interventions to promote healthy ageing. Herein, we examine how impairment in the selective degradation of damaged/dysfunctional mitochondria through mitophagy may play a central role in the loss of mitochondrial proteostasis in skeletal muscle ageing, as well as its broader implications for systemic health. Further, we explore how stimulating mitophagy through exercise may promote healthy ageing.
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Affiliation(s)
- Joshua C. Drake
- Department of MedicineUniversity of Virginia School of MedicineCharlottesvilleVA22908USA
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research CenterUniversity of Virginia School of MedicineCharlottesvilleVA22908USA
| | - Zhen Yan
- Department of MedicineUniversity of Virginia School of MedicineCharlottesvilleVA22908USA
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research CenterUniversity of Virginia School of MedicineCharlottesvilleVA22908USA
- Department of PharmacologyUniversity of Virginia School of MedicineCharlottesvilleVA22908USA
- Department of Molecular Physiology and Biological PhysicsUniversity of Virginia School of MedicineCharlottesvilleVA22908USA
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